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Sample records for diversity enhances remediation

  1. SIMULATION OF SURFACTANT-ENHANCED AQUIFER REMEDIATION

    EPA Science Inventory

    Surfactant-enhanced aquifer remediation (SEAR) is currently under active investigation as one of the most promising alternatives to conventional pump-and-treat remediation for aquifers contaminated by dense nonaqueous phase organic liquids. An existing three-dimensional finite-di...

  2. ENHANCED REMEDIATION DEMONSTRATIONS AT HILL AFB: INTRODUCTION

    EPA Science Inventory

    Nine enhanced aquifer remediation technologies were demonstrated side-by-side at a Hill Air Force Base Chemical Disposal Pit/Fire Training Area site. The demonstrations were performed inside 3 x 5 m cells isolated from the surrounding shallow aquifer by steel piling. The site w...

  3. Acoustically enhanced remediation, Phase 2: Technology scaling

    SciTech Connect

    Iovenitti, J.L.; Hill, D.G.; Rynne, T.M.; Spadaro, J.F.; Hutchinson, W.; Illangasakere, T.

    1996-12-31

    Weiss Associates is conducting the following three phase program investigating the in-situ application of acoustically enhanced remediation (AER) of contaminated unconsolidated soil and ground water under both saturated and unsaturated conditions: Phase I-- laboratory scale parametric investigation; Phase II--technology Scaling; and Phase III--large scale field tests. AER addresses the need for NAPL (either lighter or denser than water: LNAPL or DNAPL, respectively) in high and low permeability sediments, and the remediation of other types of subsurface contaminants (e.g., metals, radionuclides) in low permeability soils. This program has been placed in the U.S. Department of Energy`s (DOE`s) DNAPL product. Phase I indicated that AER could be used to effectively remediate NAPL in high permeability soil, and that removal of NAPL from low permeability soil could be increased since the water flux through these soils was significantly increased. Phase II, Technology Scaling, the subject of this paper, focused on (1) evaluating the characteristics of an AER field deployment system, (2) developing DNAPL flow and transport performance data under acoustic excitation, (3) predicting the effect of acoustic remediation in three-dimensional unconsolidated hydrogeologic conditions, (4) conducting an engineering analysis of acoustical sources, and (5) identifying candidate field site(s) for large-scale field testing of the technology.

  4. Cognitive diversity and moral enhancement.

    PubMed

    Gyngell, Chris; Easteal, Simon

    2015-01-01

    One debate in contemporary bioethics centers on whether the development of cognitive enhancement technologies (CETs) will hasten the need for moral enhancement. In this article we provide a new argument in favor of pursuing these enhancement technologies together. The widespread availability of CETs will likely increase population-level cognitive diversity. Different people will choose to enhance different aspects of their cognition, and some won't enhance themselves at all. Although this has the potential to be beneficial for society, it could also result in harms as people become more different from one another. Aspects of our moral psychology make it difficult for people to cooperate and coordinate actions with those who are very different from themselves. These moral failings could be targeted by moral enhancement technologies, which may improve cooperation among individuals. Moral enhancement technologies will therefore help society maximize the benefits, and reduce the costs, associated with widespread access to cognitive enhancements.

  5. Characterization and Monitoring Strategy for MNA and Enhanced Passive Remediation

    SciTech Connect

    Gilmore, Tyler J.; Looney, Brian B.; Riha, Brian D.; Waugh, Jody; Sink, Claire H.

    2004-06-01

    A framework for characterizing and monitoring the Monitored Natural Attenuation (MNA) and Enhanced Passive Remediation (EPR) options was developed to facilitate the use of these naturally passive remedial options. The framework provides the technical basis for evaluating, applying and monitoring MNA/EPR over the lifetime of application. The mass balance concept is used as the scientific and technical framework for this characterization and monitoring approach. The approach is organized into four transitional phases: screening characterization, decision characterization, process monitoring and system verification. The framework overlays the CERCLA process with the intent to expand the description of characterizations and monitoring and not to replace nor increase the requirements of the Remediation Investigation/Feasibility Study (RI/FS). The use of natural processes to promote cleanup is, in many ways, unique from engineered solutions. And, this framework allows MNA to be evaluated holistically taking into consideration the requirements over the lifetime of the remedy.

  6. Enhanced Amendment Delivery to Overcome Subsurface Physical Remediation Barriers

    NASA Astrophysics Data System (ADS)

    Zhong, L.; Truex, M. J.; Oostrom, M.; Szecsody, J. E.; Vermeul, V.; Li, X.

    2013-12-01

    Waste discharges can result in contamination of the unsaturated zone (vadose zone) and the water saturated zone (aquifer). To restore the environment, many in situ remediation technologies rely on delivery of remedial reagents (amendments) to the subsurface that treat or help remove contamination. However, through numerous remediation applications, the remediation industry has recognized that a major issue with in situ remediation is the difficulty in achieving an even spatial distribution of remedial amendments to the contamination zones in an aquifer or in the vadose zone. Poor amendment delivery leads to ineffective environmental restoration because some of the contaminants are not contacted by the amendment and, therefore, not treated or removed. This challenge often leads to a failure in environment restoration. Researches are being conducted to develop enhanced remediation amendment delivery approaches using shear thinning fluids (STFs) for aquifer and aqueous foams for vadose zone. STFs have properties that promote more uniform delivery of injected solutions so that amendments are able to reach low-permeability zones in an aquifer. These low-permeability zones are most difficult to reach with conventional delivery approaches, yet often contain the high contamination concentrations. Foam delivery is targeted for distribution of aqueous, gaseous amendments, and remedial nano-particles to the vadose zone. Foam transport in the vadose zone provides significant advantages for lateral distribution of amendments compared to aqueous-phase transport, improves uniformity of distribution compared to both aqueous- and gas-phase injection, and enables delivery of a broader range of remediation amendments than can be delivered in the gas phase.

  7. Enhancing the Efficiency of Electrokinetic Remediation through Technology Integration

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Komai, T.

    2009-12-01

    Remediation or cleanup of soils and groundwater polluted by heavy metals remains a challenge in the field of geo-environmental engineering. Many sites, like ore dressing plants, electroplating plants and battery factories may be polluted by heavy metals. In addition, some natural factors like metal deposits or abundant metal mines, hot springs and volcanic eruptions may also cause heavy metal pollutions. Unlike organic pollutants, heavy metals do not decay naturally, and active approaches to remediation are generally necessary. Although electrokinetic method is considered to be the only technique that is highly-perspective for in situ remediation of heavy metals, and numerous bench-scale studies as well as a few pilot scale experiments illustrated its applicability, this technique has not yet been widely used in practice due to the low efficiencies and/or unacceptable long remediation periods. To enhance the total efficiency of electrokinetic remediation, a systematic approach by integrating different technologies is proposed. This systematic approach includes 1) on-site quick mapping for screening out localized pollution areas, characterizing chemical composition of polluted soils, and for examining the progress of in situ remediation; 2) electrical resistivity tomography(ERT) or electrical resistivity imaging(ERI) for predicting geological structure and hydrogeological boundaries conditions of a polluted site, and for optimizing parameters like voltage and current density for an effective remediation; 3) the use of solar energy to increase flexibility in and applicability of electrokinetic technique; 4) combination with large scale modeling tests for a pertinent evaluation of the feasibility related to electrokinetic remediation for a given soil type taken from a specific polluted site; 5) combination with risk-assessment method to determine feasible cleanup levels; and 6) recovery of heavy metals deposited on electrode plates for possible use as resources

  8. DEMONSTRATION BULLETIN STEAM ENHANCED REMEDIATION STEAM TECH ENVIRONMENTAL SERVICES, INC.

    EPA Science Inventory

    Steam Enhanced Remediation is a process in which steam is injected into the subsurface to recover volatile and semivolatile organic contaminants. It has been applied successfully to recover contaminants from soil and aquifers and at a fractured granite site. This SITE demonstra...

  9. SURFACTANT ENHANCED AQUIFER REMEDIATION WITH SURFACTANT REGENERATION/REUSE

    EPA Science Inventory

    A demonstration of surfactant-enhanced aquifer remediation was conducted during the spring of 1999 at Marine Corps Base, Camp LeJeune, NC. A PCE-DNAPL zone was identified and delineated by extensive soil sampling in 1997, and was further characteized by a partitioning interwell t...

  10. Decontamination formulation with additive for enhanced mold remediation

    DOEpatents

    Tucker, Mark D.; Irvine, Kevin; Berger, Paul; Comstock, Robert

    2010-02-16

    Decontamination formulations with an additive for enhancing mold remediation. The formulations include a solubilizing agent (e.g., a cationic surfactant), a reactive compound (e.g., hydrogen peroxide), a carbonate or bicarbonate salt, a water-soluble bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate), a mold remediation enhancer containing Fe or Mn, and water. The concentration of Fe.sup.2+ or Mn.sup.2+ ions in the aqueous mixture is in the range of about 0.0001% to about 0.001%. The enhanced formulations can be delivered, for example, as a foam, spray, liquid, fog, mist, or aerosol for neutralization of chemical compounds, and for killing certain biological compounds or agents and mold spores, on contaminated surfaces and materials.

  11. Microemulsion-enhanced remediation of soils contaminated with organochlorine pesticides.

    PubMed

    Zhang, Yanlin; Wong, Jonathan W C; Zhao, Zhenyong; Selvam, Ammaiyappan

    2011-12-01

    Soil contaminated by organic pollutants, especially chlorinated aromatic compounds such as DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane), is an environmental concern because of the strong sorption of organochlorine pesticide onto the soil matrix and persistence in the environment. The remediation of organochlorine pesticide contaminated soils through microemulsion is an innovative technology to expedite this process. The remediation efficiency was evaluated by batch experiments through studying the desorption of DDT and hexachlorocyclohexane (y-HCH) and sorption of microemulsion composed of Triton X-100, 1-pentanol and linseed oil in the soil-surfactant-water suspension system. The reduction of desorption efficiency caused by the sorption loss of microemulsion components onto the soil could be corrected by the appropriate adjustment of C/S (Cosurfactant/Surfactant) and O/S (Oil/Surfactant) ratio. The C/S and O/S ratios of 1:2 and 3:20 were suitable to desorb DDT and gamma-HCH from the studied soils because of the lower sorption of Triton X-100 onto the soil. Inorganic salts added in microemulsion increased the pesticides desorption efficiency of pesticides and calcium chloride has a stronger ability to enhance the desorption of DDT than sodium chloride. From the remediation perspective, the balance of surfactant or cosurfactant sorbed to soil and desorption efficiency should be taken into consideration to enhance the remediation of soils contaminated by organochlorine pesticides.

  12. Sustainable Remediation for Enhanced NAPL Recovery from Groundwater

    NASA Astrophysics Data System (ADS)

    Javaher, M.

    2012-12-01

    Sustainable remediation relates to the achievement of balance between environmental, social, and economic elements throughout the remedial lifecycle. A significant contributor to this balance is the use of green and sustainable technologies which minimize environmental impacts, while maximizing social and economic benefits of remedial implementation. To this end, a patented mobile vapor energy generation (VEG) technology has been developed targeting variable applications, including onsite soil remediation for unrestricted reuse and enhanced non-aqueous phase liquid (NAPL) recover at the water table. At the core of the mobile VEG technology is a compact, high efficiency vapor generator, which utilizes recycled water and propane within an entirely enclosed system to generate steam as high as 1100°F. Operating within a fully enclosed system and capturing all heat that is generated within this portable system, the VEG technology eliminates all emissions to the atmosphere and yields an undetected carbon footprint with resulting carbon dioxide concentrations that are below ambient levels. Introduction of the steam to the subsurface via existing wells results in a desired change in the NAPL viscosity and the interfacial tension at the soil, water, NAPL interface; in turn, this results in mobilization and capture of the otherwise trapped, weathered NAPL. Approved by the California Air Resources Control Board (and underlying Air Quality Management Districts) and applied in California's San Joaquin Valley, in-well heating of NAPLs trapped at the water table using the VEG technology has proven as effective as electrical resistivity heating (ERH) in changing the viscosity of and mobilizing NAPLs in groundwater in support of recovery, but has achieved these results while minimizing the remedial carbon footprint by 90%, reducing energy use by 99%, and reducing remedial costs by more than 95%. NAPL recovery using VEG has also allowed for completion of source removal historically

  13. [Anolyte enhanced electrokinetic remediation of fluorine-contaminated soils].

    PubMed

    Zhu, Shu-Fa; Yan, Chun-Li; Dong, Tie-You; Tang, Hong-Yan

    2009-07-15

    An experimental study was carried out in order to determine the characteristics of migration and its influencing factor of soil fluorine in the electrokinetic process under different applied voltage and concentration of anolyte. The feasibility of anolyte enhanced on electrokinetic remediation of fluorine-contaminated soil was analyzed. The results show that when deionized water is used as anolyte with the 1.0 V/cm voltage gradient, the cumulative mass of fluorine in catholyte and anolyte are 8.2 mg and 47.7 mg respectively and the removal rate of fluorine is only 8.8%. Anolyte enhanced electrokinetic process can promote effectively the migration of fluoride in soil. When 0.02 mol/L NaOH solutionis employed as the anolyte, the removal rates are 25.9%, 31.2% and 47.3% with 1.0, 1.5 and 2.0 V/cm voltage gradient respectively. As the concentration of anolyte increased to 0.1 mol/L, the removal rates are 55.4%, 61.1% and 73.0%. The electromigration is the main transport mechanism and the electroosmotic flow has an effect on the migration of fluorine in soil. The voltage gradient and the concentration of anolyte are the main factors influencing the removal rate of fluorine in soil. Appropriate anolyte enhanced electrokinetic method can be applied to remediate fluorine from contaminated soil.

  14. Enhancement of in situ microbial remediation of aquifers

    DOEpatents

    Fredrickson, James K.; Brockman, Fred J.; Streile, Gary P.; Cary, John W.; McBride, John F.

    1993-01-01

    Methods are provided for remediating subsurface areas contaminated by toxic organic compounds. An innocuous oil, such as vegetable oil, mineral oil, or other immiscible organic liquid, is introduced into the contaminated area and permitted to move therethrough. The oil concentrates or strips the organic contaminants, such that the concentration of the contaminants is reduced and such contaminants are available to be either pumped out of the subsurface area or metabolized by microorganisms. Microorganisms may be introduced into the contaminated area to effect bioremediation of the contamination. The methods may be adapted to deliver microorganisms, enzymes, nutrients and electron donors to subsurface zones contaminated by nitrate in order to stimulate or enhance denitrification.

  15. Enhancing the diversity of the pediatrician workforce.

    PubMed

    Friedman, Aaron L

    2007-04-01

    This policy statement describes the key issues related to diversity within the pediatrician and health care workforce to identify barriers to enhancing diversity and offer policy recommendations to overcome these barriers in the future. The statement addresses topics such as health disparities, affirmative action, recent policy developments and reports on workforce diversity, and research on patient and provider diversity. It also broadens the discussion of diversity beyond the traditional realms of race and ethnicity to include cultural attributes that may have an effect on the quality of health care. Although workforce diversity is related to the provision of culturally effective pediatric care, it is a discrete issue that merits separate discussion and policy formulation. At the heart of this policy-driven action are multiorganizational and multispecialty collaborations designed to address substantive educational, financial, organizational, and other barriers to improved workforce diversity. PMID:17403859

  16. Surfactant-enhanced remediation of organic contaminated soil and water.

    PubMed

    Paria, Santanu

    2008-04-21

    Surfactant based remediation technologies for organic contaminated soil and water (groundwater or surface water) is of increasing importance recently. Surfactants are used to dramatically expedite the process, which in turn, may reduce the treatment time of a site compared to use of water alone. In fact, among the various available remediation technologies for organic contaminated sites, surfactant based process is one of the most innovative technologies. To enhance the application of surfactant based technologies for remediation of organic contaminated sites, it is very important to have a better understanding of the mechanisms involved in this process. This paper will provide an overview of the recent developments in the area of surfactant enhanced soil and groundwater remediation processes, focusing on (i) surfactant adsorption on soil, (ii) micellar solubilization of organic hydrocarbons, (iii) supersolubilization, (iv) density modified displacement, (v) degradation of organic hydrocarbon in presence surfactants, (vi) partitioning of surfactants onto soil and liquid organic phase, (vii) partitioning of contaminants onto soil, and (viii) removal of organics from soil in presence of surfactants. Surfactant adsorption on soil and/or sediment is an important step in this process as it results in surfactant loss reduced the availability of the surfactants for solubilization. At the same time, adsorbed surfactants will retained in the soil matrix, and may create other environmental problem. The biosurfactants are become promising in this application due to their environmentally friendly nature, nontoxic, low adsorption on to soil, and good solubilization efficiency. Effects of different parameters like the effect of electrolyte, pH, soil mineral and organic content, soil composition etc. on surfactant adsorption are discussed here. Micellar solubilization is also an important step for removal of organic contaminants from the soil matrix, especially for low aqueous

  17. Hydraulic characterization for steam enhanced remediation conducted in fractured rock.

    PubMed

    Stephenson, Kyle M; Novakowski, Kent; Davis, Eva; Heron, Gorm

    2006-01-10

    To explore the viability of Steam Enhanced Remediation (SER) in fractured rock a small-scale steam injection and water/vapour extraction pilot study was conducted at the former Loring Air Force Base in northern Maine, USA. A detailed well testing program was undertaken to assist in the design of the injection and extraction well array, and to assess the possibility of off-site heat and contaminant migration. A structurally complex limestone having low matrix porosity and a sparse distribution of fractures underlies the study site. To characterize the groundwater and steam flow pathways, single-well slug tests and more than 100 pulse interference tests were conducted. The results of the well testing indicate that the study site is dominated by steeply dipping bedding plane fractures that are interconnected only between some wells in the injection/extraction array. The SER system was designed to take advantage of interconnected fractures located at depth in the eastern end of the site. An array of 29 wells located in an area of 60 by 40 m was used for steam injection and water/vapour extraction. The migration of heat was monitored in several wells using thermistor arrays having a 1.5 m vertical spacing. Temperature measurements obtained during and after the 3 month steam injection period showed that heat migration generally occurred along those fracture features identified by the pulse interference testing. Based on these results, it is concluded that the pulse interference tests were valuable in assisting with the design of the injection/extraction well geometry and in predicting the migration pathways of the hot water associated with the steam injection. The pulse interference test method should also prove useful in support of any other remedial method dependant on the fracture network for delivery of remedial fluid or extraction of contaminants.

  18. Enhancement of in situ microbial remediation of aquifers

    DOEpatents

    Fredrickson, J.K.; Brockman, F.J.; Streile, G.P.; Cary, J.W.; McBride, J.F.

    1993-11-30

    Methods are provided for remediating subsurface areas contaminated by toxic organic compounds. An innocuous oil, such as vegetable oil, mineral oil, or other immiscible organic liquid, is introduced into the contaminated area and permitted to move therethrough. The oil concentrates or strips the organic contaminants, such that the concentration of the contaminants is reduced and such contaminants are available to be either pumped out of the subsurface area or metabolized by microorganisms. Microorganisms may be introduced into the contaminated area to effect bioremediation of the contamination. The methods may be adapted to deliver microorganisms, enzymes, nutrients and electron donors to subsurface zones contaminated by nitrate in order to stimulate or enhance denitrification. 4 figures.

  19. Multi objective optimization of the setup of a surfactant-enhanced DNAPL remediation.

    PubMed

    Schaerlaekens, Jan; Carmeliet, Jan; Feyen, Jan

    2005-04-01

    Surfactant-enhanced aquifer remediation (SEAR) is widely considered a promising technique to remediate dense nonaqueous phase liquid (DNAPL) contaminations in-situ. The costs of a SEAR remediation are important and depend mostly on the setup of the remediation. Costs can be associated with the installation of injection and extraction wells, the required time of the remediation (and thus labor costs, lease of installations, and energy), the extracted water volume (the purification of the extracted water), and the injected surfactant amount. A cost-effective design of the remediation setup allows an optimal use of resources. In this work, a SEAR remediation was simulated for a hypothetical typical DNAPL contamination. A constrained multi-objective optimization of the model was applied to obtain a Pareto set of optimal remediation strategies with different weights for the two objectives of the remediation: (i) the maximal removal of DNAPL mass (ii) with a minimal total cost. A relatively sharp Pareto front was found, showing a considerable tradeoff between DNAPL removal and total remediation costs. These Pareto curves can help decision makers select an optimal remediation strategy in terms of cost and remediation efficiency depending on external constraints such as the available budget and obligatory remediation goals.

  20. From "Remedial English" to "English Enhancement" (So, What Else Is New?).

    ERIC Educational Resources Information Center

    Allison, Desmond

    1992-01-01

    The case against a "remedial" view of English as a Second Language (ESL) is presented, and an alternative approach is offered: an "enhancement" account of programs that aim to improve students' command of English in the course of an English-medium college or university education. The transition from "remedial" to "enhancement" provisions within…

  1. Integrating diverse datasets improves developmental enhancer prediction.

    PubMed

    Erwin, Genevieve D; Oksenberg, Nir; Truty, Rebecca M; Kostka, Dennis; Murphy, Karl K; Ahituv, Nadav; Pollard, Katherine S; Capra, John A

    2014-06-01

    Gene-regulatory enhancers have been identified using various approaches, including evolutionary conservation, regulatory protein binding, chromatin modifications, and DNA sequence motifs. To integrate these different approaches, we developed EnhancerFinder, a two-step method for distinguishing developmental enhancers from the genomic background and then predicting their tissue specificity. EnhancerFinder uses a multiple kernel learning approach to integrate DNA sequence motifs, evolutionary patterns, and diverse functional genomics datasets from a variety of cell types. In contrast with prediction approaches that define enhancers based on histone marks or p300 sites from a single cell line, we trained EnhancerFinder on hundreds of experimentally verified human developmental enhancers from the VISTA Enhancer Browser. We comprehensively evaluated EnhancerFinder using cross validation and found that our integrative method improves the identification of enhancers over approaches that consider a single type of data, such as sequence motifs, evolutionary conservation, or the binding of enhancer-associated proteins. We find that VISTA enhancers active in embryonic heart are easier to identify than enhancers active in several other embryonic tissues, likely due to their uniquely high GC content. We applied EnhancerFinder to the entire human genome and predicted 84,301 developmental enhancers and their tissue specificity. These predictions provide specific functional annotations for large amounts of human non-coding DNA, and are significantly enriched near genes with annotated roles in their predicted tissues and lead SNPs from genome-wide association studies. We demonstrate the utility of EnhancerFinder predictions through in vivo validation of novel embryonic gene regulatory enhancers from three developmental transcription factor loci. Our genome-wide developmental enhancer predictions are freely available as a UCSC Genome Browser track, which we hope will enable

  2. Compatibility of polymers and chemical oxidants for enhanced groundwater remediation.

    PubMed

    Smith, Megan M; Silva, Jeff A K; Munakata-Marr, Junko; McCray, John E

    2008-12-15

    Polymer floods provide a promising method to more effectively deliver conventional groundwater treatment agents to organic contaminants distributed within heterogeneous aquifer systems. Combinations of nontoxic polymers (xanthan and hydrolyzed polyacrylamide) and common chemical oxidants (potassium permanganate and sodium persulfate) were investigated to determine the suitability of these mixtures for polymer-enhanced in situ chemical oxidation applications. Oxidant demand and solution viscosity were utilized as initial measures of chemical compatibility. After 72 h of reaction with both test oxidants, solution viscosities in mixtures containing hydrolyzed polyacrylamide were decreased by more than 90% (final viscosities approximately 2 cP), similar to the 95% viscosity loss (final viscosities approximately 1 cP, near that of water) observed in xanthan/persulfate experiments. In contrast, xanthan solutions exposed to potassium permanganate preserved 60-95% of initial viscosity after 72 h. Permanganate depletion in xanthan-containing experiments ranged from 2% to 24% over the same test period. Although oxidant consumption in xanthan/permanganate solutions appeared to be correlated with increasing xanthan concentrations, solutions of up to 2000 mg/L xanthan did not inhibit permanganate from oxidizing a dissolved-phase test contaminant (tetrachloroethene, PCE) in xanthan solution. These advantageous characteristics (high viscosity retention, moderate oxidant demand, and lack of competitive effects on PCE oxidation rate) render xanthan/permanganate the most compatible polymer/oxidant combination of those tested for remediation by polymer-enhanced chemical oxidation. PMID:19174907

  3. Compatibility of polymers and chemical oxidants for enhanced groundwater remediation.

    PubMed

    Smith, Megan M; Silva, Jeff A K; Munakata-Marr, Junko; McCray, John E

    2008-12-15

    Polymer floods provide a promising method to more effectively deliver conventional groundwater treatment agents to organic contaminants distributed within heterogeneous aquifer systems. Combinations of nontoxic polymers (xanthan and hydrolyzed polyacrylamide) and common chemical oxidants (potassium permanganate and sodium persulfate) were investigated to determine the suitability of these mixtures for polymer-enhanced in situ chemical oxidation applications. Oxidant demand and solution viscosity were utilized as initial measures of chemical compatibility. After 72 h of reaction with both test oxidants, solution viscosities in mixtures containing hydrolyzed polyacrylamide were decreased by more than 90% (final viscosities approximately 2 cP), similar to the 95% viscosity loss (final viscosities approximately 1 cP, near that of water) observed in xanthan/persulfate experiments. In contrast, xanthan solutions exposed to potassium permanganate preserved 60-95% of initial viscosity after 72 h. Permanganate depletion in xanthan-containing experiments ranged from 2% to 24% over the same test period. Although oxidant consumption in xanthan/permanganate solutions appeared to be correlated with increasing xanthan concentrations, solutions of up to 2000 mg/L xanthan did not inhibit permanganate from oxidizing a dissolved-phase test contaminant (tetrachloroethene, PCE) in xanthan solution. These advantageous characteristics (high viscosity retention, moderate oxidant demand, and lack of competitive effects on PCE oxidation rate) render xanthan/permanganate the most compatible polymer/oxidant combination of those tested for remediation by polymer-enhanced chemical oxidation.

  4. Geoscience Diversity Enhancement Project: Student Responses.

    ERIC Educational Resources Information Center

    Rodrigue, Christine M.; Wechsler, Suzanne P.; Whitney, David J.; Ambos, Elizabeth L.; Ramirez-Herrera, Maria Teresa; Behl, Richard; Francis, Robert D.; Larson, Daniel O.; Hazen, Crisanne

    This paper describes an interdisciplinary project at California State University (Long Beach) designed to increase the attractiveness of the geosciences to underrepresented groups. The project is called the Geoscience Diversity Enhancement Project (GDEP). It is a 3-year program which began in the fall of 2001 with funding from the National Science…

  5. A multi-objective optimization framework for surfactant-enhanced remediation of DNAPL contaminations.

    PubMed

    Schaerlaekens, Jan; Mertens, Jan; Van Linden, Jan; Vermeiren, Gert; Carmeliet, Jan; Feyen, Jan

    2006-08-10

    The occurrence of Dense Non-Aqueous Phase Liquid (DNAPL) contaminations in the subsurface is a threat for drinkwater resources in the western world. Surfactant-Enhanced Aquifer Remediation (SEAR) is widely considered as one of the most promising techniques to remediate DNAPL contaminations in-situ, be it with considerable additional costs compared to classical pump-and-treat remediations. A cost-effective design of the remediation set-up is therefore essential. In this work, a pilot SEAR test is executed at a DNAPL contaminated site in Belgium in order to collect data for the calibration of a multi-phase multi-component model. The calibrated model is used to assess a series of scenario-analyses for the full-scale remediation of the site. The remediation variables that were varied were the injection and extraction rate, the injection and extraction duration, and the surfactant injection concentrations. A constrained multi-objective optimization of the model was applied to obtain a Pareto set of optimal remediation strategies with different weights for the two objectives of the remediation: (i) the maximal removal of DNAPL and (ii) a total minimal cost. These Pareto curves can help decision makers to select an optimal remediation strategy in terms of cost and remediation efficiency. The Pareto front shows a considerable trade-off between the total remediation cost and the removed DNAPL mass.

  6. Sand amendment enhances bioelectrochemical remediation of petroleum hydrocarbon contaminated soil.

    PubMed

    Li, Xiaojing; Wang, Xin; Ren, Zhiyong Jason; Zhang, Yueyong; Li, Nan; Zhou, Qixing

    2015-12-01

    Bioelectrochemical system is an emerging technology for the remediation of soils contaminated by petroleum hydrocarbons. However, performance of such systems can be limited by the inefficient mass transport in soil. Here we report a new method of sand amendment, which significantly increases both oxygen and proton transports, resulting to increased soil porosity (from 44.5% to 51.3%), decreased Ohmic resistance (by 46%), and increased charge output (from 2.5 to 3.5Cg(-1)soil). The degradation rates of petroleum hydrocarbons increased by up to 268% in 135d. The degradation of n-alkanes and polycyclic aromatic hydrocarbons with high molecular weight was accelerated, and denaturing gradient gel electrophoresis showed that the microbial community close to the air-cathode was substantially stimulated by the induced current, especially the hydrocarbon degrading bacteria Alcanivorax. The bioelectrochemical stimulation imposed a selective pressure on the microbial community of anodes, including that far from the cathode. These results suggested that sand amendment can be an effective approach for soil conditioning that will enhances the bioelectrochemical removal of hydrocarbons in contaminated soils.

  7. Fracture enhanced in-situ foam remediation. Topical report, July 1995-December 1996

    SciTech Connect

    Chowdiah, P.; Misra, B.R.; Conrad, J.R.; Srivastava, V.J.

    1997-06-01

    The objective of this project was to determine the technical feasibility of soil fracturing as an enhancement to transportation of foam and foam-assisted site remediation. This project is part of an overall effort by the Gas Research Institute (GRI) to develop technologies for cost-effective, in-situ remediation of soils.

  8. The Use of Enhanced Bioremediation at the Savannah River Site to Remediate Pesticides and PCBs

    SciTech Connect

    Beul, R.

    2003-09-30

    Enhanced bioremediation is quickly developing into an economical and viable technology for the remediation of contaminated soils. Until recently, chlorinated organic compounds have proven difficult to bioremediate. This article reviews the ongoing remediation occurring at the Chemicals, Metals, and Pesticides (CMP) Pits using windrow turners to facilitate microbial degradation of certain pesticides and PCBs.

  9. Enhanced Remedial Amendment Delivery through Fluid Viscosity Modifications: Experiments and numerical simulations

    SciTech Connect

    Zhong, Lirong; Oostrom, Martinus; Wietsma, Thomas W.; Covert, Matthew A.

    2008-07-29

    Abstract Heterogeneity is often encountered in subsurface contamination characterization and remediation. Low-permeability zones are typically bypassed when remedial fluids are injected into subsurface heterogeneous aquifer systems. Therefore, contaminants in the bypassed areas may not be contacted by the amendments in the remedial fluid, which may significantly prolong the remediation operations. Laboratory experiments and numerical studies have been conducted to develop the Mobility-Controlled Flood (MCF) technology for subsurface remediation and to demonstrate the capability of this technology in enhancing the remedial amendments delivery to the lower permeability zones in heterogeneous systems. Xanthan gum, a bio-polymer, was used to modify the viscosity of the amendment-containing remedial solutions. Sodium mono-phosphate and surfactant were the remedial amendment used in this work. The enhanced delivery of the amendments was demonstrated in two-dimensional (2-D) flow cell experiments, packed with heterogeneous systems. The impact of polymer concentration, fluid injection rate, and permeability contract in the heterogeneous systems has been studied. The Subsurface Transport over Multiple Phases (STOMP) simulator was modified to include polymer-induced shear thinning effects. Shear rates of polymer solutions were computed from pore-water velocities using a relationship proposed in the literature. Viscosity data were subsequently obtained from empirical viscosity-shear rate relationships derived from laboratory data. The experimental and simulation results clearly show that the MCF technology is capable of enhancing the delivery of remedial amendments to subsurface lower permeability zones. The enhanced delivery significantly improved the NAPL removal from these zones and the sweeping efficiency on a heterogeneous system was remarkably increased when a polymer fluid was applied. MCF technology is also able to stabilize the fluid displacing front when there is a

  10. Evolution of transcriptional enhancers and animal diversity

    PubMed Central

    Rubinstein, Marcelo; de Souza, Flávio S. J.

    2013-01-01

    Deciphering the genetic bases that drive animal diversity is one of the major challenges of modern biology. Although four decades ago it was proposed that animal evolution was mainly driven by changes in cis-regulatory DNA elements controlling gene expression rather than in protein-coding sequences, only now are powerful bioinformatics and experimental approaches available to accelerate studies into how the evolution of transcriptional enhancers contributes to novel forms and functions. In the introduction to this Theme Issue, we start by defining the general properties of transcriptional enhancers, such as modularity and the coexistence of tight sequence conservation with transcription factor-binding site shuffling as different mechanisms that maintain the enhancer grammar over evolutionary time. We discuss past and current methods used to identify cell-type-specific enhancers and provide examples of how enhancers originate de novo, change and are lost in particular lineages. We then focus in the central part of this Theme Issue on analysing examples of how the molecular evolution of enhancers may change form and function. Throughout this introduction, we present the main findings of the articles, reviews and perspectives contributed to this Theme Issue that together illustrate some of the great advances and current frontiers in the field. PMID:24218630

  11. Evolution of transcriptional enhancers and animal diversity.

    PubMed

    Rubinstein, Marcelo; de Souza, Flávio S J

    2013-12-19

    Deciphering the genetic bases that drive animal diversity is one of the major challenges of modern biology. Although four decades ago it was proposed that animal evolution was mainly driven by changes in cis-regulatory DNA elements controlling gene expression rather than in protein-coding sequences, only now are powerful bioinformatics and experimental approaches available to accelerate studies into how the evolution of transcriptional enhancers contributes to novel forms and functions. In the introduction to this Theme Issue, we start by defining the general properties of transcriptional enhancers, such as modularity and the coexistence of tight sequence conservation with transcription factor-binding site shuffling as different mechanisms that maintain the enhancer grammar over evolutionary time. We discuss past and current methods used to identify cell-type-specific enhancers and provide examples of how enhancers originate de novo, change and are lost in particular lineages. We then focus in the central part of this Theme Issue on analysing examples of how the molecular evolution of enhancers may change form and function. Throughout this introduction, we present the main findings of the articles, reviews and perspectives contributed to this Theme Issue that together illustrate some of the great advances and current frontiers in the field.

  12. CHEMICAL ENHANCEMENTS TO PUMP-AND-TREAT REMEDIATION

    EPA Science Inventory

    Conventional pump-and-treat technologies are among the most widely used systems for the remediation of contaminated ground-water. ithin recent years it has become recognized that these systems can require protracted periods of time to make significant reductions in the quantity o...

  13. HYDRAULIC CHARACTERIZATION FOR STEAM ENHANCED REMEDIATION CONDUCTED IN FRACTURED ROCK

    EPA Science Inventory

    Remediation of fractured rock sites contaminated by non-aqueous phase liquids has long been recognized as the most difficult undertaking of any site clean-up. This is primarily the result of the complexity of the fracture framework, which governs the groundwater flow pathways and...

  14. Bio-enhanced thin-spreading: A low cost soil remediation alternative

    SciTech Connect

    Wong, G.; Pfarrer, R. III

    1996-11-01

    Products manufactured at Kohler Company`s Kohler, Wisconsin plant include a variety of plumbing fixtures, including vitreous china toilets and sinks, cast iron enameled sinks and tubs, electroplated faucets, assorted plumbing fittings, and small engines. This paper focuses on a soil remediation project performed at the Kohler Company`s Kohler, Wisconsin facility. In order to implement this soil remediation project, close coordination and communication was required with many project entities including numerous company departments, contractors, regulatory agencies, and the general public. Using an innovative and cost-effective soil treatment method called bio-enhanced thin-spreading (BETS), over 5,000 cubic yards of kerosene-contaminated soils were successfully remediated. The purpose of this case study is: (1) to describe the technical aspects of the remediation project including the BETS soil treatment method; and (2) to discuss factors which can significantly influence the development, management, and implementation of environmental remediation projects at large manufacturing facilities.

  15. Enhanced electrokinetic remediation of lead-contaminated soil by complexing agents and approaching anodes.

    PubMed

    Zhang, Tao; Zou, Hua; Ji, Minhui; Li, Xiaolin; Li, Liqiao; Tang, Tang

    2014-02-01

    Optimizing process parameters that affect the remediation time and power consumption can improve the treatment efficiency of the electrokinetic remediation as well as determine the cost of a remediation action. Lab-scale electrokinetic remediation of Pb-contaminated soils was investigated for the effect of complexant ethylenediaminetetraacetic acid (EDTA) and acetic acid and approaching anode on the removal efficiency of Pb. When EDTA was added to the catholyte, EDTA dissolved insoluble Pb in soils to form soluble Pb-EDTA complexes, increasing Pb mobility and accordingly removal efficiency. The removal efficiency was enhanced from 47.8 to 61.5 % when the EDTA concentration was increased from 0.1 to 0.2 M, showing that EDTA played an important role in remediation. And the migration rate of Pb was increased to 72.3 % when both EDTA and acetic acid were used in the catholyte. The "approaching anode electrokinetic remediation" process in the presence of both EDTA and acetic acid had a higher Pb-removal efficiency with an average efficiency of 83.8 %. The efficiency of electrokinetic remediation was closely related to Pb speciation. Exchangeable and carbonate-bounded Pb were likely the forms which could be removed. All results indicate that the approaching anode method in the presence of EDTA and acetic acid is an advisable choice for electrokinetic remediation of Pb-contaminated soil. PMID:24203258

  16. Electrokinetic remediation of organochlorines in soil: enhancement techniques and integration with other remediation technologies.

    PubMed

    Gomes, Helena I; Dias-Ferreira, Celia; Ribeiro, Alexandra B

    2012-06-01

    Electrokinetic remediation has been increasingly used in soils and other matrices for numerous contaminants such as inorganic, organic, radionuclides, explosives and their mixtures. Several strategies were tested to improve this technology effectiveness, namely techniques to solubilize contaminants, control soil pH and also couple electrokinetics with other remediation technologies. This review focus in the experimental work carried out in organochlorines soil electroremediation, aiming to systemize useful information to researchers in this field. It is not possible to clearly state what technique is the best, since experimental approaches and targeted contaminants are different. Further research is needed in the application of some of the reviewed techniques. Also a number of technical and environmental issues will require evaluation for full-scale application. Removal efficiencies reported in real contaminated soils are much lower than the ones obtained with spiked kaolinite, showing the influence of other factors like aging of the contamination and adsorption to soil particles, resulting in important challenges when transferring technologies into the field. PMID:22386462

  17. Diverse pollinator communities enhance plant reproductive success

    PubMed Central

    Albrecht, Matthias; Schmid, Bernhard; Hautier, Yann; Müller, Christine B.

    2012-01-01

    Understanding the functional consequences of biodiversity loss is a major goal of ecology. Animal-mediated pollination is an essential ecosystem function and service provided to mankind. However, little is known how pollinator diversity could affect pollination services. Using a substitutive design, we experimentally manipulated functional group (FG) and species richness of pollinator communities to investigate their consequences on the reproductive success of an obligate out-crossing model plant species, Raphanus sativus. Both fruit and seed set increased with pollinator FG richness. Furthermore, seed set increased with species richness in pollinator communities composed of a single FG. However, in multiple-FG communities, highest species richness resulted in slightly reduced pollination services compared with intermediate species richness. Our analysis indicates that the presence of social bees, which showed roughly four times higher visitation rates than solitary bees or hoverflies, was an important factor contributing to the positive pollinator diversity–pollination service relationship, in particular, for fruit set. Visitation rate at different daytimes, and less so among flower heights, varied among social bees, solitary bees and hoverflies, indicating a niche complementarity among these pollinator groups. Our study demonstrates enhanced pollination services of diverse pollinator communities at the plant population level and suggests that both the niche complementarity and the presence of specific taxa in a pollinator community drive this positive relationship. PMID:23034701

  18. Heating Unsaturated Sediments Using Solar Energy to Enhance Passive Sediment Remediation Technologies

    NASA Astrophysics Data System (ADS)

    Rossman, A.

    2002-12-01

    Sediment heating has been shown to enhance passive sediment remediation technologies such as bioremediation and barometric pumping (passive soil venting). Sediment heating raises the slow remediation rates that often limit the widespread use of these technologies. In bioremediation applications, a 10 degree C increase in subsurface temperature is expected to double the microbial activity, and thus the remediation rate. The removal rate of tetracholorethylene (PCE - a common subsurface contaminant) by passive soil vapor extraction is expected to nearly double in low-permeable sediments when the subsurface is heated 10 degree C from ambient temperatures due to an increased vapor pressure in the PCE. When the sediment is heated using renewable energy sources, these thermally enhanced remediation technologies can be environmentally benign alternatives to conventional remediation techniques that rely on large external energy inputs. The thermally enhanced passive technologies may be particularly useful for remediating unsaturated, low-permeable lenses that are troublesome to most conventional remediation technologies such as conventional soil vapor extraction and co-solvent flushes. The main objective of this work was to quantify subsurface sediment heating using a solar powered heat injection well. To do this, a pilot sediment heating system was installed in Vermont and high resolution meteorological and sediment temperature data were collected using a stand-alone data acquisition system. Unsaturated, silty sediments were heated in-situ by converting the direct and indirect solar energy available at the surface to heat energy in the subsurface using stand-alone renewable energy sources and a resistive element heat injection well. The heat injection well was powered by a 600-W passively tracking photovoltaic (PV) array and a small 1.2-m swept area wind turbine. It is envisioned that the heat injection well would be placed directly into an area of high subsurface

  19. Enhanced remedial amendment delivery through fluid viscosity modifications: experiments and numerical simulations.

    PubMed

    Zhong, L; Oostrom, M; Wietsma, T W; Covert, M A

    2008-10-23

    Low-permeability zones are typically bypassed when remedial fluids are injected into subsurface heterogeneous aquifer systems. Therefore, contaminants in the bypassed areas may not be contacted by the amendments in the remedial fluid, which may significantly prolong remediation operations. Laboratory experiments and numerical studies have been conducted to investigate the use of a shear-thinning polymer (Xanthan gum) to improve access to low-permeability zones in heterogeneous systems. The chemicals sodium mono-phosphate and the surfactant MA-80 were used as the remedial amendments. The impact of polymer concentration, fluid injection rate, and permeability contrast in the heterogeneous systems has been studied in a series of eleven two-dimensional flow cell experiments. The Subsurface Transport over Multiple Phases (STOMP) simulator was modified to include polymer-induced shear-thinning effects. The experimental and simulation results clearly show that using the polymer leads to an enhanced delivery of remedial amendments to lower-permeability zones and an increased sweeping efficiency. An added benefit of using the polymer is the stabilization of the displacing front when density differences exist between displaced and displacing fluids. The modified STOMP simulator was able to predict the experimental observed fluid displacing behavior well and might be used to predict subsurface remediation performance when a shear-thinning fluid is used to remediate a heterogeneous system at larger scales.

  20. Engineered Injection and Extraction for Enhanced In-situ Remediation of Sorbing Solutes in Groundwater

    NASA Astrophysics Data System (ADS)

    Webber, B. D.; Neupauer, R. M.; Piscopo, A. N.; Mays, D. C.

    2012-12-01

    Groundwater remediation is becoming increasingly more important as the world's population grows and the necessity of access to clean drinking water persists. The majority of current groundwater treatment methods involve pumping the contaminated groundwater out of the soil and treating it above ground. Sorbed contaminants are difficult to remediate using this conventional pump-and-treat method, and often produce poor treatment results because sorbed contaminants are difficult to extract from the aquifer; therefore in-situ remediation research is of particular importance. One type of in-situ groundwater remediation involves a treatment solution of varying composition being injected into the polluted aquifer to react with the contaminant and degrade it to an acceptable byproduct. Increasing the amount of spreading between the contaminant and the treatment solution promotes an increase in contact area and more desired reactions. It has been previously determined that sequential injection and extraction using four wells for in-situ remediation can enhance the spreading of an aqueous contaminant and treatment solution and increase degradation through more reactions. In this work, we focus on sorbing contaminants and investigate the effectiveness of the injection and extraction methods on varying degrees of contaminant sorption. Tests were conducted in homogeneous and heterogeneous soil media, and with instantaneous and kinetic reaction. It was determined that engineered injection and extraction methods previously developed for aqueous contaminants also enhance in-situ remediation of sorbing solutes.

  1. Ammonium citrate as enhancement for electrodialytic soil remediation and investigation of soil solution during the process.

    PubMed

    Dias-Ferreira, Celia; Kirkelund, Gunvor M; Ottosen, Lisbeth M

    2015-01-01

    Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm(-2)), concentration of enhancing agent (0.25, 0.5 and 1.0 M) and remediation times (21, 42 and 117 d) for the removal of Cu and Cr from a calcareous soil. To gain insight on metal behavior, soil solution was periodically collected using suction cups. It was seen that current densities higher than 1.0 mA cm(-2) did not increase removal and thus using too high current densities can be a waste of energy. Desorption rate is important and both remediation time and ammonium citrate concentration are relevant parameters. It was possible to collect soil solution samples following an adaptation of the experimental set-up to ensure continuous supply of ammonium citrate to the soil in order to keep it saturated during the remediation. Monitoring soil solution gives valuable information on the evolution of remediation and helps deciding when the soil is remediated. Final concentrations in the soil ranged from 220 to 360 mg Cu kg(-1) (removals: 78-86%) and 440-590 mg Cr kg(-1) (removals: 35-51%), being within the 500 mg kg(-1) limit for a clean soil only for Cu. While further optimization is still required for Cr, the removal percentages are the highest achieved so far, for a real Cu and Cr-contaminated, calcareous soil. The results highlight EDR potential to remediate metal polluted soils at neutral to alkaline pH by choosing a good enhancement solution.

  2. Ammonium citrate as enhancement for electrodialytic soil remediation and investigation of soil solution during the process.

    PubMed

    Dias-Ferreira, Celia; Kirkelund, Gunvor M; Ottosen, Lisbeth M

    2015-01-01

    Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm(-2)), concentration of enhancing agent (0.25, 0.5 and 1.0 M) and remediation times (21, 42 and 117 d) for the removal of Cu and Cr from a calcareous soil. To gain insight on metal behavior, soil solution was periodically collected using suction cups. It was seen that current densities higher than 1.0 mA cm(-2) did not increase removal and thus using too high current densities can be a waste of energy. Desorption rate is important and both remediation time and ammonium citrate concentration are relevant parameters. It was possible to collect soil solution samples following an adaptation of the experimental set-up to ensure continuous supply of ammonium citrate to the soil in order to keep it saturated during the remediation. Monitoring soil solution gives valuable information on the evolution of remediation and helps deciding when the soil is remediated. Final concentrations in the soil ranged from 220 to 360 mg Cu kg(-1) (removals: 78-86%) and 440-590 mg Cr kg(-1) (removals: 35-51%), being within the 500 mg kg(-1) limit for a clean soil only for Cu. While further optimization is still required for Cr, the removal percentages are the highest achieved so far, for a real Cu and Cr-contaminated, calcareous soil. The results highlight EDR potential to remediate metal polluted soils at neutral to alkaline pH by choosing a good enhancement solution. PMID:25240953

  3. Enhancing Student Compositional Diversity in the Sociology Classroom

    ERIC Educational Resources Information Center

    Lyon, Katherine A.; Guppy, Neil

    2016-01-01

    It is well documented that interaction between diverse students encourages positive learning outcomes. Given this, we examine how to enhance the quantity and quality of student diversity in university classrooms. Drawing on sociological theory linking life experiences with ways of knowing, we investigate how to increase classroom diversity by…

  4. STEAM ENHANCED REMEDIATION RESEARCH FOR DNAPL IN FRACTURED ROCK, LORING AIR FORCE BASE, LIMESTONE, MAINE

    EPA Science Inventory

    This report details a research project on Steam Enhanced Remediation (SER) for the recovery of volatile organic compounds from fractured limestone that was carried out at the Quarry at the former Loring Air Force Base in Limestone, Maine. This project was carried out by USEPA, Ma...

  5. Enhanced Remedial Amendment Delivery to Subsurface Using Shear Thinning Fluid and Aqueous Foam

    SciTech Connect

    Zhong, Lirong; Szecsody, James E.; Oostrom, Martinus; Truex, Michael J.; Shen, Xin; Li, Xiqing

    2011-04-23

    A major issue with in situ subsurface remediation is the ability to achieve an even spatial distribution of remedial amendments to the contamination zones in an aquifer or vadose zone. Delivery of amendment to the aquifer using shear thinning fluid and to the vadose zone using aqueous foam has the potential to enhance the amendment distribution into desired locations and improve the remediation. 2-D saturated flow cell experiments were conducted to evaluate the enhanced sweeping, contaminant removal, and amendment persistence achieved by shear thinning fluid delivery. Bio-polymer xanthan gum solution was used as the shear thinning fluid. Unsaturated 1-D column and 2-D flow cell experiments were conducted to evaluate the mitigation of contaminant mobilization, amendment uniform distribution enhancement, and lateral delivery improvement by foam delivery. Surfactant sodium lauryl ether sulfate was used as the foaming agent. It was demonstrated that the shear thinning fluid injection enhanced the fluid sweeping over a heterogeneous system and increased the delivery of remedial amendment into low-permeability zones. The persistence of the amendment distributed into the low-perm zones by the shear thinning fluid was prolonged compared to that of amendment distributed by water injection. Foam delivery of amendment was shown to mitigate the mobilization of highly mobile contaminant from sediments under vadose zone conditions. Foam delivery also achieved more uniform amendment distribution in a heterogeneous unsaturated system, and demonstrated remarkable increasing in lateral distribution of the injected liquid compared to direct liquid injection.

  6. POTENTIAL ENHANCEMENTS TO NATURAL ATTENUATION: LINES OF INQUIRY SUPPORTING ENHANCED PASSIVE REMEDIATION OF CHLORINATED SOLVENTS

    SciTech Connect

    Vangelas, K; Tom Early, T; Michael Heitkamp, M; Brian02 Looney, B; David Major, D; Brian Riha, B; Jody Waugh, J; Gary Wein, G

    2004-06-18

    The Department of Energy (DOE) is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Passive Remediation (EPR) for chlorinated solvents. This Office of Environmental Management (EM) ''Alternative Project,'' focuses on providing scientific and policy support for MNA/EPR. A broadly representative working group of scientists supports the project along with partnerships with regulatory organizations such as the Interstate Technology and Regulatory Council and the U.S. Environmental Protection Agency (EPA). The initial product of the technical working group was a summary report that articulated the conceptual approach and central scientific tenants of the project, and that identified a prioritized listing of technical targets for field research. This report documented the process in which: (1) scientific ground rules were developed, (2) lines of inquiry were identified and then critically evaluated, (3) promising applied research topics were highlighted in the various lines of inquiry, and (4) these were discussed and prioritized. The summary report will serve as a resource to guide management and decision-making throughout the period of the subject MNA/EPR Alternative Project. To support and more fully document the information presented in the summary report, we are publishing a series of supplemental documents that present the full texts from the technical analyses within the various lines of inquiry (see listing). The following report - documenting our evaluation of the state of the science of the characterization and monitoring process and tools-- is one of those supplemental documents.

  7. Enhancing electrokinetic remediation of cadmium- contaminated soils with stepwise moving anode method.

    PubMed

    Chen, Xue J; Shen, Zhe M; Yuan, Tao; Zheng, Shen S; Ju, Bing X; Wang, Wen H

    2006-01-01

    This paper proposed an innovative approach by stepwise moving anode towards cathode to enhance the cadmium (Cd) removal from soil during the process of electrokinetic (EK) remediation. Fixed anode tests and moving anode tests were carried out for 60 hours to compare their performances. The anode-cathode spacing was 21 cm. Constant voltage grade of 1.0 V cm(-1) was applied in this study. The parameters included pH, electrical conductivity, current, Cd concentration and speciation distributions, energy consumptions, etc. It was found that the pH values in the moving anode tests were relatively lower than those of the fixed tests. In the moving anode test, the removal efficiency of Cd in the soils at the fraction of S4 was enhanced by 54.9% compared with that of the fixed anode tests. After 60 hours of treatment, approximately 80% of the spiked soils (100.63 mg x kg(-1) of Cd) in the system were successfully remedied in the moving anode tests; and the mean removal efficiency was 73% for actual field-contaminated soil (54.26 mg x kg(-1) of Cd). It is effective to remedy actual contaminated soils. In addition, the cumulative energy consumptions were 59.29 kWhm(-3) and 31.52 kWhm(-3) for the fixed and moving tests, respectively. The results revealed that the Cd removal efficiency was improved by the moving anode method. Moreover, less energy was consumed in the moving test. The proposed approach does not need to introduce extra chemicals nor adjust the pH in the system to enhance the Cd removal by EK remediation. The basic idea proposed in this paper provides a novel and environmental friendly method to enhance the EK remediation of heavy metals contaminated soils. PMID:17000543

  8. Acoustically enhanced remediation of contaminated soils and ground water. Volume 1

    SciTech Connect

    1995-10-01

    The Phase 1 laboratory bench-scale investigation results have shown that acoustically enhanced remediation (AER) technology can significantly accelerate the ground water remediation of non-aqueous phase liquids (NAPLs) in unconsolidated soils. The testing also determined some of the acoustic parameters which maximize fluid and contaminant extraction rates. A technology merit and trade analysis identified the conditions under which AER could be successfully deployed in the field, and an analysis of existing acoustical sources and varying methods for their deployment found that AER technology can be successfully deployed in-situ. Current estimates of deployability indicate that a NAPL plume 150 ft in diameter can be readily remediated. This program focused on unconsolidated soils because of the large number of remediation sites located in this type of hydrogeologic setting throughout the nation. It also focused on NAPLs and low permeability soil because of the inherent difficult in the remediation of NAPLs and the significant time and cost impact caused by contaminated low permeability soils. This overall program is recommended for Phase 2 which will address the technology scaling requirements for a field scale test.

  9. [Microwave thermal remediation of soil contaminated with crude oil enhanced by granular activated carbon].

    PubMed

    Li, Da-Wei; Zhang, Yao-Bin; Quan, Xie; Zhao, Ya-Zhi

    2009-02-15

    The advantage of rapid, selective and simultaneous heating of microwave heating technology was taken to remediate the crude oil-contaminated soil rapidly and to recover the oil contaminant efficiently. The contaminated soil was processed in the microwave field with addition of granular activated carbon (GAC), which was used as strong microwave absorber to enhance microwave heating of the soil mixture to remove the oil contaminant and recover it by a condensation system. The influences of some process parameters on the removal of the oil contaminant and the oil recovery in the remediation process were investigated. The results revealed that, under the condition of 10.0% GAC, 800 W microwave power, 0.08 MPa absolute pressure and 150 mL x min(-1) carrier gas (N2) flow-rate, more than 99% oil removal could be obtained within 15 min using this microwave thermal remediation enhanced by GAC; at the same time, about 91% of the oil contaminant could be recovered without significant changes in chemical composition. In addition, the experiment results showed that GAC can be reused in enhancing microwave heating of soil without changing its enhancement efficiency obviously.

  10. Microwave thermal remediation of crude oil contaminated soil enhanced by carbon fiber.

    PubMed

    Li, Dawei; Zhang, Yaobin; Quan, Xie; Zhao, Yazhi

    2009-01-01

    Thermal remediation of the soil contaminated with crude oil using microwave heating enhanced by carbon fiber (CF) was explored. The contaminated soil was treated with 2.45 GHz microwave, and CF was added to improve the conversion of microwave energy into thermal energy to heat the soil. During microwave heating, the oil contaminant was removed from the soil matrix and recovered by a condensation system of ice-salt bath. The experimental results indicated that CF could efficiently enhance the microwave heating of soil even with relatively low-dose. With 0.1 wt.% CF, the soil could be heated to approximately 700 degrees C within 4 min using 800 W of microwave irradiation. Correspondingly, the contaminated soil could be highly cleaned up in a short time. Investigation of oil recovery showed that, during the remediation process, oil contaminant in the soil could be efficiently recovered without causing significant secondary pollution.

  11. Optimal Well Placement for Enhanced Degradation during In Situ Groundwater Remediation

    NASA Astrophysics Data System (ADS)

    Greene, J. A.; Neupauer, R.; Piscopo, A. N.; Kasprzyk, J. R.

    2015-12-01

    Active spreading strategies have been developed to enhance contaminant degradation during in situ remediation by increasing contact of the injected treatment chemical with the contaminant plume. The contact between these reactants is increased by strategically injecting and extracting water at wells surrounding the plume to reconfigure the treatment chemical and contaminant plume in the aquifer, which leads to enhanced contaminant degradation. The distance and orientation of the wells relative to the contaminant plume affects the ability of active spreading strategies to efficiently degrade contaminant. In this study, we use a multi-objective evolutionary algorithm to optimize the distance and orientation of wells for both circular and elliptical contaminant plumes with uniform and Gaussian initial concentration distributions. The optimization yields results that maximize the amount of degradation achieved during in situ remediation while minimizing any extraction of treatment chemical.

  12. Emerging Opportunities for School Psychologists to Enhance our Remediation Procedure Evidence Base as We Apply Response to Intervention

    ERIC Educational Resources Information Center

    Skinner, Christopher H.; McCleary, Daniel F.; Skolits, Gary L.; Poncy, Brian C.; Cates, Gary L.

    2013-01-01

    The success of Response-to-Intervention (RTI) and similar models of service delivery is dependent on educators being able to apply effective and efficient remedial procedures. In the process of implementing problem-solving RTI models, school psychologists have an opportunity to contribute to and enhance the quality of our remedial-procedure…

  13. Analysis of the Effects of the Computer Enhanced Classroom on the Achievement of Remedial High School Math Students.

    ERIC Educational Resources Information Center

    Lang, William Steve; And Others

    The effects of the use of computer-enhanced instruction with remedial students were assessed, using 4,293 ninth through twelfth graders--3,308 Black, 957 White, and 28 Other--involved in the Governor's Remediation Initiative (GRI) in Georgia. Data sources included the Comprehensive Tests of Basic Skills (CTBS), a data collection form developed for…

  14. Innovative Programs for Improvement in Reading through Cognitive Enhancement: A Remediation Study of Canadian First Nations Children

    ERIC Educational Resources Information Center

    Hayward, Denyse; Das, J. P.; Janzen, Troy

    2007-01-01

    Forty-five Grade 3 students from a reservation school in Western Canada were divided into two remedial groups and a no-risk control group. One remedial group was given a classroom-administered cognitive enhancement program (COGENT) throughout the school year. The second group received COGENT for the first half of the year followed by a pull-out…

  15. Mobility Controlled Flooding (MCF) Technology for Enhanced Sweeping and NAPL Remediation in Heterogeneous Systems

    NASA Astrophysics Data System (ADS)

    Zhong, L.; Oostrom, M.; Wietsma, T.

    2005-12-01

    Heterogeneity is often encountered in subsurface contamination characterization and remediation. Low-permeability zones are bypassed when remedial fluid is injected into heterogeneous systems. The contaminant in the bypassed areas is therefore untouched by the remedial fluid, which can prolong the remediation operations significantly. Methods of forcing fluids into low-permeability flow paths have been developed and widely implemented to solve the heterogeneity-induced bypassing problem encountered during oil recovery in the petroleum industry over the past 40 years. Since the intent of the petroleum reservoir engineers is to control the mobility of the injected fluid in the high-permeable zones so that the fluid can be pushed through the low-permeable zones to contact and mobilize the remaining oil in these zones, this method are referred as mobility controlled flooding (MCF) technology in the petroleum engineering literature. Two methods of mobility control have been developed. One method is to use a water-soluble polymer to increase the viscosity of the injectate so that the in situ pore pressure is raised, and cross-flow between layers with different permeability occurs. The other method is to use surfactant-foam flood to generate foam in high permeable zones in situ; therefore, the injected fluid is forced into the low-permeable areas. A water-soluble polymer, xanthan gum, and surfactant MA-80 was used to formulate MCF remedial fluids to remediate nonaqueous phase liquid (NAPL) contaminated heterogonous systems in two-dimensional (2-D) flow-cell (40 by 50 by 5 cm) experiments. It was demonstrated that the MCF technology is capable of sweeping the low-permeability flow paths. The bypassing of low-permeable zones was significantly reduced. The removal of NAPL trapped in the low-perm zones was remarkable enhanced attributed to more efficient NAPL mobilization. The results also indicate that the MCF technology is able to manage the fluid density effects. The

  16. Enhanced remedial amendment delivery to subsurface using shear thinning fluid and aqueous foam.

    PubMed

    Zhong, Lirong; Szecsody, Jim; Oostrom, Mart; Truex, Mike; Shen, Xin; Li, Xiqing

    2011-07-15

    A major issue with in situ subsurface remediation is the ability to achieve an even spatial distribution of remedial amendments to the contamination zones in an aquifer or vadose zone. Amendment delivery to the aquifer using shear thinning fluid and to the vadose zone using aqueous foam has the potential to enhance the distribution. 2-D saturated flow cell experiments were conducted to evaluate the enhanced fluid sweeping over heterogeneous system, improved contaminant removal, and extended amendment presence in low-permeability zones achieved by shear thinning fluid delivery. Unsaturated column and flow cell experiments were conducted to investigate the improvement on contaminant mobilization mitigation, amendment distribution, and lateral delivery implemented by foam delivery. It was demonstrated that the shear thinning fluid injection enhanced the fluid sweeping and increased the delivery of remedial amendment into low-perm zones. The presence of amendment distributed by the shear thinning fluid in the low-permeability zones was increased. Foam delivery was shown to mitigate the mobilization of highly mobile contaminant from sediments. It also achieved more uniform amendment distribution in a heterogeneous unsaturated system, and demonstrated remarkable increasing in lateral distribution of the injected liquid compared to direct liquid injection.

  17. Development, Discouragement, or Diversion? New Evidence on the Effects of College Remediation Policy

    ERIC Educational Resources Information Center

    Scott-Clayton, Judith; Rodriguez, Olga

    2015-01-01

    Half of all college students will enroll in remedial coursework but evidence of its effectiveness is mixed. Using a regression-discontinuity design with data from a large urban community college system, we make three contributions. First, we articulate three alternative hypotheses regarding the potential impacts of remediation. Second, in addition…

  18. Optimization of surfactant-enhanced aquifer remediation for a laboratory BTEX system under parameter uncertainty.

    PubMed

    He, Li; Huang, Guo-He; Lu, Hong-Wei; Zeng, Guang-Ming

    2008-03-15

    This study develops a nonlinear chance-constrained programming (NCCP) model for optimizing surfactant-enhanced aquifer remediation (SEAR) processes. The model can not only address the parameter uncertainty, but provide a reliability level for the identified optimal remediation strategy. To solve the NCCP model, stepwise cluster analysis (SCA) is used to create a set of proxy simulators for quantifying the relationships between operating conditions (i.e., pumping rate) and probabilities of benzene levels in violation of standard. Compared to conventional parametric inference techniques, SCA is independent of prior assumptions for model forms (e.g., linear or exponential ones) and capable of reflecting complex nonlinear relationships between operating conditions and probabilities. To alleviate the computational efforts in the optimization process, the generated proxy simulators are repeatedly called by simulated annealing (SA) to test the feasibility of each potential solution. The implicit of the optimal NCCP solutions is discussed through a laboratory-scale SEAR system where porosity and intrinsic permeability are treated as stochastic parameters. It is observed that well locations, environmental standards, reliability levels and remediation durations would have significant effects on optimal SEAR strategies. By comparing the predicted benzene concentration without and with remediation actions, it is indicated that the optimal SEAR process can guarantee the benzene concentration to meet the environmental standard with a high reliability level.

  19. Future HIV Mentoring Programs to Enhance Diversity.

    PubMed

    Stoff, David M; Cargill, Victoria A

    2016-09-01

    This paper proposes a general template to guide future mentoring program development addressing: (i) considerations to ensure an adequate research workforce; (ii) key guidelines and principles of mentoring; and (iii) use of a logic model to develop program milestones, outcomes and evaluation. We focus on these areas to guide and inform the most effective mentoring program components, which we find to be more helpful than identifying specific features and ingredients. Although the focus is on the development of a new generation of investigators from diverse backgrounds, this template may also apply to mentoring programs for other investigators and for disciplines beyond HIV. PMID:27484059

  20. In-situ demonstration of radio-frequency enhanced chlorinated hydrocarbon remediation

    SciTech Connect

    Kasevich, R.S.; Price, S.L.; Faust, D.L.; Jarosch, T.R.

    1994-06-01

    This paper discusses the results of a successful demonstration of radio frequency (RF) heating for enhanced chlorinated hydrocarbon remediation at the M-Area Seepage Basin of the Department of Energy`s Savannah River Site. RF heating was integrated with soil vapor extraction (SVE) to enhance the release of residual volatile chlorinated hydrocarbons which are concentrated in low permeable clay lenses in the unsaturated zone. Participants in this effort consisted of the Westinghouse Savannah River Technology Center; the Westinghouse Science and Technology Center (Pittsburgh, PA); and KAI Technologies, Inc. which provided the RF technology. Additionally, a better understanding of RF heating technology is gained through a description of the RF heating system.

  1. Selecting enhancing solutions for electrokinetic remediation of dredged sediments polluted with fuel.

    PubMed

    Rozas, F; Castellote, M

    2015-03-15

    In this paper a procedure for selecting the enhancing solutions in electrokinetic remediation experiments is proposed. For this purpose, dredged marine sediment was contaminated with fuel, and a total of 22 different experimental conditions were tested, analysing the influence of different enhancing solutions by using three commercial non-ionic surfactants, one bio-surfactant, one chelating agent, and one weak acid. Characterisation, microelectrophoretic and electrokinetic remediation trials were carried out. The results are explained on the basis of the interactions between the fuel, the enhancing electrolytes and the matrix. For one specific system, the electrophoretic zeta potential, (ζ), of the contaminated matrix in the solution was found to be related to the electroosmotic averaged ζ in the experiment and not to the efficiency in the extraction. This later was correlated to a parameter accounting for both contributions, the contaminant and the enhancing solution, calculated on the basis of differences in the electrophoretic ζ in different conditions which has allowed to propose a methodology for selection of enhancing solutions. PMID:25559497

  2. Laboratory {open_quotes}proof of principle{close_quotes} investigation for the acoustically enhanced remediation technology

    SciTech Connect

    Iovenitti, J.L.; Spencer, J.W.; Hill, D.G.

    1995-12-01

    This document describes a three phase program of Weiss Associates which investigates the systematics of using acoustic excitation fields (AEFs) to enhance the in-situ remediation of contaminated soil and ground water under both saturated and unsaturated conditions. The focus in this particular paper is a laboratory proof of principle investigation. The field deployment and engineering viability of acoustically enhanced remediation technology is also examined.

  3. Effect of heterogeneity on enhanced reductive dechlorination: Analysis of remediation efficiency and groundwater acidification

    NASA Astrophysics Data System (ADS)

    Brovelli, A.; Lacroix, E.; Robinson, C. E.; Gerhard, J.; Holliger, C.; Barry, D. A.

    2011-12-01

    Enhanced reductive dehalogenation is an attractive in situ treatment technology for chlorinated contaminants. The process includes two acid-forming microbial reactions: fermentation of an organic substrate resulting in short-chain fatty acids, and dehalogenation resulting in hydrochloric acid. The accumulation of acids and the resulting drop of groundwater pH are controlled by the mass and distribution of chlorinated solvents in the source zone, type of electron donor, alternative terminal electron acceptors available and presence of soil mineral phases able to buffer the pH (such as carbonates). Groundwater acidification may reduce or halt microbial activity, and thus dehalogenation, significantly increasing the time and costs required to remediate the aquifer. In previous work a detailed geochemical and groundwater flow simulator able to model the fermentation-dechlorination reactions and associated pH change was developed. The model accounts for the main processes influencing microbial activity and groundwater pH, including the groundwater composition, the electron donor used and soil mineral phase interactions. In this study, the model was applied to investigate how spatial variability occurring at the field scale affects dechlorination rates, groundwater pH and ultimately the remediation efficiency. Numerical simulations were conducted to examine the influence of heterogeneous hydraulic conductivity on the distribution of the injected, fermentable substrate and on the accumulation/dilution of the acidic products of reductive dehalogenation. The influence of the geometry of the DNAPL source zone was studied, as well as the spatial distribution of soil minerals. The results of this study showed that the heterogeneous distribution of the soil properties have a potentially large effect on the remediation efficiency. For examples, zones of high hydraulic conductivity can prevent the accumulation of acids and alleviate the problem of groundwater acidification. The

  4. Diversity Enhances NPP, N Retention, and Soil Microbial Diversity in Experimental Urban Grassland Assemblages

    PubMed Central

    Thompson, Grant L.; Kao-Kniffin, Jenny

    2016-01-01

    Urban grasslands, landscapes dominated by turfgrasses for aesthetic or recreational groundcovers, are rapidly expanding in the United States and globally. These managed ecosystems are often less diverse than the natural or agricultural lands they replace, leading to potential losses in ecosystem functioning. Research in non-urban systems has provided evidence for increases in multiple ecosystem functions associated with greater plant diversity. To test if biodiversity-ecosystem function findings are applicable to urban grasslands, we examined the effect of plant species and genotypic diversity on three ecosystem functions, using grassland assemblages of increasing diversity that were grown within a controlled environment facility. We found positive effects of plant diversity on reduced nitrate leaching and plant productivity. Soil microbial diversity (Mean Shannon Diversity, H’) of bacteria and fungi were also enhanced in multi-species plantings, suggesting that moderate increments in plant diversity influence the composition of soil biota. The results from this study indicate that plant diversity impacts multiple functions that are important in urban ecosystems; therefore, further tests of urban grassland biodiversity should be examined in situ to determine the feasibility of manipulating plant diversity as an explicit landscape design and function trait. PMID:27243768

  5. An enhanced adaptive management approach for remediation of legacy mercury in the South River.

    PubMed

    Foran, Christy M; Baker, Kelsie M; Grosso, Nancy R; Linkov, Igor

    2015-01-01

    Uncertainties about future conditions and the effects of chosen actions, as well as increasing resource scarcity, have been driving forces in the utilization of adaptive management strategies. However, many applications of adaptive management have been criticized for a number of shortcomings, including a limited ability to learn from actions and a lack of consideration of stakeholder objectives. To address these criticisms, we supplement existing adaptive management approaches with a decision-analytical approach that first informs the initial selection of management alternatives and then allows for periodic re-evaluation or phased implementation of management alternatives based on monitoring information and incorporation of stakeholder values. We describe the application of this enhanced adaptive management (EAM) framework to compare remedial alternatives for mercury in the South River, based on an understanding of the loading and behavior of mercury in the South River near Waynesboro, VA. The outcomes show that the ranking of remedial alternatives is influenced by uncertainty in the mercury loading model, by the relative importance placed on different criteria, and by cost estimates. The process itself demonstrates that a decision model can link project performance criteria, decision-maker preferences, environmental models, and short- and long-term monitoring information with management choices to help shape a remediation approach that provides useful information for adaptive, incremental implementation.

  6. Cosolubilization synergism occurrence in codesorption of PAH mixtures during surfactant-enhanced remediation of contaminated soil.

    PubMed

    Liang, Xujun; Guo, Chuling; Wei, Yanfu; Lin, Weijia; Yi, Xiaoyun; Lu, Guining; Dang, Zhi

    2016-02-01

    Surfactant-enhanced remediation (SER) has been widely applied in decontaminating PAH-polluted soil. Most researches focus on evaluating washing efficiency without considering pollutants' mutual interaction. This study aims to investigate cosolubilization effect between phenanthrene (Phe) and pyrene (Pyr) in nonionic surfactant Triton X-100 (TX100) solution on their codesorption performance from soil. Cosolubilization experiment showed that, when cosolubilized, solubility of Phe and Pyr in TX100 increased by 15.38% and 18.19%, respectively, as quantified by the deviation ratio of molar solubilization ratio in single and binary solute solubilization systems. The synergism may be due to the enlarged micelle volume caused by PAHs solubilized in the shell region of the micelle. The cosolubilization effect was further observed in the soil washing process. The strengthened TX100 solubilization capacity towards Phe and Pyr could increase the two PAHs' codesorption efficiency from soil, accompanied by synergistic extent of 6-15%. However, synergism in codesorption was weaker than that observed in the cosolubilization system, which may be related to surfactant loss to soil and PAH partition into soil organic matter and the sorbed surfactants. The improved remediation performance during codesorption of mixed PAHs implies the significance of combining PAHs' mutual interaction into evaluating SER, which may reduce the surfactant washing concentration and save remediation cost. PMID:26397474

  7. Teaching Strategies for Enhancing Peer Interaction among Diverse Learners

    ERIC Educational Resources Information Center

    Sit, Helena Hing Wa

    2012-01-01

    Hong Kong's universities have been attracting non-local students to diversify the overall student mix and enhance internationalism in higher education. Mainland Chinese students have become the largest non-local student source in this Western-style higher education sector. The diversity of student body together with the promotion of multicultural…

  8. Remediation of Nitrobenzene Contaminated Soil by Combining Surfactant Enhanced Soil Washing and Effluent Oxidation with Persulfate

    PubMed Central

    Yan, Jingchun; Gao, Weiguo; Qian, Linbo; Han, Lu; Chen, Yun; Chen, Mengfang

    2015-01-01

    The combination of surfactant enhanced soil washing and degradation of nitrobenzene (NB) in effluent with persulfate was investigated to remediate NB contaminated soil. Aqueous solution of sodium dodecylbenzenesulfonate (SDBS, 24.0 mmol L-1) was used at a given mass ratio of solution to soil (20:1) to extract NB contaminated soil (47.3 mg kg-1), resulting in NB desorption removal efficient of 76.8%. The washing effluent was treated in Fe2+/persulfate and Fe2+/H2O2 systems successively. The degradation removal of NB was 97.9%, being much higher than that of SDBS (51.6%) with addition of 40.0 mmol L-1 Fe2+ and 40.0 mmol L-1 persulfate after 15 min reaction. The preferential degradation was related to the lone pair electron of generated SO4•−, which preferably removes electrons from aromatic parts of NB over long alkyl chains of SDBS through hydrogen abstraction reactions. No preferential degradation was observed in •OH based oxidation because of its hydrogen abstraction or addition mechanism. The sustained SDBS could be reused for washing the contaminated soil. The combination of the effective surfactant-enhanced washing and the preferential degradation of NB with Fe2+/persulfate provide a useful option to remediate NB contaminated soil. PMID:26266532

  9. Enhanced removal of petroleum hydrocarbons using a bioelectrochemical remediation system with pre-cultured anodes.

    PubMed

    Venkidusamy, Krishnaveni; Megharaj, Mallavarapu; Marzorati, Massimo; Lockington, Robin; Naidu, Ravi

    2016-01-01

    Bioelectrochemical remediation (BER) systems such as microbial fuel cells (MFCs) have recently emerged as a green technology for the effective remediation of petroleum hydrocarbon contaminants (PH) coupled with simultaneous energy recovery. Recent research has shown that biofilms previously enriched for substrate degrading bacteria resulted in excellent performance in terms of substrate removal and electricity generation but the effects on hydrocarbon contaminant degradation were not examined. Here we investigate the differences between enriched biofilm anodes and freshly inoculated new anodes in diesel fed single chamber mediatorless microbial fuel cells (DMFC) using various techniques for the enhancement of PH contaminant remediation with concomitant electricity generation. An anodophilic microbial consortium previously selected for over a year through continuous culturing with a diesel concentration of about 800mgl(-1) and which now showed complete removal of this concentration of diesel within 30days was compared to that of a freshly inoculated new anode MFC (showing 83.4% removal of diesel) with a simultaneous power generation of 90.81mW/m(2) and 15.04mW/m(2) respectively. The behaviour of pre-cultured anodes at a higher concentration of PH (8000mgl(-1)) was also investigated. Scanning electron microscopy observation revealed a thick biofilm covering the pre-cultured anodic electrode but not the anode from the freshly inoculated MFC. High resolution imaging showed the presence of thin 60nm diametre pilus-like projections emanating from the cells. Anodic microbial community profiling confirmed that the selection for diesel degrading exoelectrogenic bacteria had occurred. Identification of a biodegradative gene (alkB) provided strong evidence of the catabolic pathway used for diesel degradation in the DMFCs.

  10. Enhanced removal of petroleum hydrocarbons using a bioelectrochemical remediation system with pre-cultured anodes.

    PubMed

    Venkidusamy, Krishnaveni; Megharaj, Mallavarapu; Marzorati, Massimo; Lockington, Robin; Naidu, Ravi

    2016-01-01

    Bioelectrochemical remediation (BER) systems such as microbial fuel cells (MFCs) have recently emerged as a green technology for the effective remediation of petroleum hydrocarbon contaminants (PH) coupled with simultaneous energy recovery. Recent research has shown that biofilms previously enriched for substrate degrading bacteria resulted in excellent performance in terms of substrate removal and electricity generation but the effects on hydrocarbon contaminant degradation were not examined. Here we investigate the differences between enriched biofilm anodes and freshly inoculated new anodes in diesel fed single chamber mediatorless microbial fuel cells (DMFC) using various techniques for the enhancement of PH contaminant remediation with concomitant electricity generation. An anodophilic microbial consortium previously selected for over a year through continuous culturing with a diesel concentration of about 800mgl(-1) and which now showed complete removal of this concentration of diesel within 30days was compared to that of a freshly inoculated new anode MFC (showing 83.4% removal of diesel) with a simultaneous power generation of 90.81mW/m(2) and 15.04mW/m(2) respectively. The behaviour of pre-cultured anodes at a higher concentration of PH (8000mgl(-1)) was also investigated. Scanning electron microscopy observation revealed a thick biofilm covering the pre-cultured anodic electrode but not the anode from the freshly inoculated MFC. High resolution imaging showed the presence of thin 60nm diametre pilus-like projections emanating from the cells. Anodic microbial community profiling confirmed that the selection for diesel degrading exoelectrogenic bacteria had occurred. Identification of a biodegradative gene (alkB) provided strong evidence of the catabolic pathway used for diesel degradation in the DMFCs. PMID:26360455

  11. Functional and mechanistic diversity of distal transcription enhancers

    PubMed Central

    Bulger, Michael; Groudine, Mark

    2013-01-01

    Biological differences among metazoans, and between cell types in a given organism, arise in large part due to differences in gene expression patterns. The sequencing of multiple metazoan genomes, coupled with recent advances in genome-wide analysis of histone modifications and transcription factor binding, has revealed that among regulatory DNA sequences, gene-distal enhancers appear to exhibit the greatest diversity and cell-type specificity. Moreover, such elements are emerging as important targets for mutations that can give rise to disease and to genetic variability that underlies evolutionary change. Studies of long-range interactions between distal genomic sequences in the nucleus indicate that enhancers are often important determinants of nuclear organization, contributing to a general model for enhancer function that involves direct enhancer-promoter contact. In a number of systems, however, mechanisms for enhancer function are emerging that do not fit solely within such a model, suggesting that enhancers as a class of DNA regulatory element may be functionally and mechanistically diverse. PMID:21295696

  12. Induced metal redistribution and bioavailability enhancement in contaminated river sediment during in situ biogeochemical remediation.

    PubMed

    Liu, Tongzhou; Zhang, Zhen; Mao, Yanqing; Yan, Dickson Y S

    2016-04-01

    In situ sediment remediation using Ca(NO3)2 or CaO2 for odor mitigation and acid volatile sulfide (AVS) and organic pollutant (such as TPH and PAHs) removal was reported in many studies and fieldwork. Yet, the associated effects on metal mobilization and potential distortion in bioavailability were not well documented. In this study, contaminated river sediment was treated by Ca(NO3)2 and CaO2 in bench studies. Through the investigation of AVS removal, organic matter removal, the changes in sediment oxidation-reduction potential (ORP), microbial activity, and other indigenous parameters, the effects on metal bioavailability, bioaccessibility, and fraction redistribution in sediment were evaluated. The major mechanisms for sediment treated by Ca(NO3)2 and CaO2 are biostimulation with indigenous denitrifying bacteria and chemical oxidation, respectively. After applying Ca(NO3)2 and CaO2, the decreases of metal concentrations in the treated sediment were insignificant within a 35-day incubation period. However, the [SEMtot-AVS]/f OC increased near to the effective boundary of toxicity (100 μmol g(-1) organic carbon (OC)), indicating that both bioavailability and bioaccessibility of metals (Cu, Zn, and Ni) to benthic organisms are enhanced after remediation. Metals were found redistributed from relatively stable fractions (oxidizable and residual fractions) to weakly bound fractions (exchangeable and reducible fractions), and the results are in line with the enhanced metal bioavailability. Compared with Ca(NO3)2, CaO2 led to higher enhancement in metal bioavailability and bioaccessibility, and more significant metal redistribution, probably due to its stronger chemical reactive capacity to AVS and sediment organic matter. The reactions in CaO2-treated sediment would probably shift from physicochemical to biochemical heterotrophic oxidation for sediment organic matter degradation. Therefore, further investigation on the long-term metal redistribution and associated

  13. Induced metal redistribution and bioavailability enhancement in contaminated river sediment during in situ biogeochemical remediation.

    PubMed

    Liu, Tongzhou; Zhang, Zhen; Mao, Yanqing; Yan, Dickson Y S

    2016-04-01

    In situ sediment remediation using Ca(NO3)2 or CaO2 for odor mitigation and acid volatile sulfide (AVS) and organic pollutant (such as TPH and PAHs) removal was reported in many studies and fieldwork. Yet, the associated effects on metal mobilization and potential distortion in bioavailability were not well documented. In this study, contaminated river sediment was treated by Ca(NO3)2 and CaO2 in bench studies. Through the investigation of AVS removal, organic matter removal, the changes in sediment oxidation-reduction potential (ORP), microbial activity, and other indigenous parameters, the effects on metal bioavailability, bioaccessibility, and fraction redistribution in sediment were evaluated. The major mechanisms for sediment treated by Ca(NO3)2 and CaO2 are biostimulation with indigenous denitrifying bacteria and chemical oxidation, respectively. After applying Ca(NO3)2 and CaO2, the decreases of metal concentrations in the treated sediment were insignificant within a 35-day incubation period. However, the [SEMtot-AVS]/f OC increased near to the effective boundary of toxicity (100 μmol g(-1) organic carbon (OC)), indicating that both bioavailability and bioaccessibility of metals (Cu, Zn, and Ni) to benthic organisms are enhanced after remediation. Metals were found redistributed from relatively stable fractions (oxidizable and residual fractions) to weakly bound fractions (exchangeable and reducible fractions), and the results are in line with the enhanced metal bioavailability. Compared with Ca(NO3)2, CaO2 led to higher enhancement in metal bioavailability and bioaccessibility, and more significant metal redistribution, probably due to its stronger chemical reactive capacity to AVS and sediment organic matter. The reactions in CaO2-treated sediment would probably shift from physicochemical to biochemical heterotrophic oxidation for sediment organic matter degradation. Therefore, further investigation on the long-term metal redistribution and associated

  14. A remediation performance model for enhanced metabolic reductive dechlorination of chloroethenes in fractured clay till.

    PubMed

    Manoli, Gabriele; Chambon, Julie C; Bjerg, Poul L; Scheutz, Charlotte; Binning, Philip J; Broholm, Mette M

    2012-04-01

    A numerical model of metabolic reductive dechlorination is used to describe the performance of enhanced bioremediation in fractured clay till. The model is developed to simulate field observations of a full scale bioremediation scheme in a fractured clay till and thereby to assess remediation efficiency and timeframe. A relatively simple approach is used to link the fermentation of the electron donor soybean oil to the sequential dechlorination of trichloroethene (TCE) while considering redox conditions and the heterogeneous clay till system (clay till matrix, fractures and sand stringers). The model is tested on lab batch experiments and applied to describe sediment core samples from a TCE-contaminated site. Model simulations compare favorably to field observations and demonstrate that dechlorination may be limited to narrow bioactive zones in the clay matrix around fractures and sand stringers. Field scale simulations show that the injected donor is expected to be depleted after 5 years, and that without donor re-injection contaminant rebound will occur in the high permeability zones and the mass removal will stall at 18%. Long remediation timeframes, if dechlorination is limited to narrow bioactive zones, and the need for additional donor injections to maintain dechlorination activity may limit the efficiency of ERD in low-permeability media. Future work should address the dynamics of the bioactive zones, which is essential to understand for predictions of long term mass removal.

  15. A remediation performance model for enhanced metabolic reductive dechlorination of chloroethenes in fractured clay till

    NASA Astrophysics Data System (ADS)

    Manoli, Gabriele; Chambon, Julie C.; Bjerg, Poul L.; Scheutz, Charlotte; Binning, Philip J.; Broholm, Mette M.

    2012-04-01

    A numerical model of metabolic reductive dechlorination is used to describe the performance of enhanced bioremediation in fractured clay till. The model is developed to simulate field observations of a full scale bioremediation scheme in a fractured clay till and thereby to assess remediation efficiency and timeframe. A relatively simple approach is used to link the fermentation of the electron donor soybean oil to the sequential dechlorination of trichloroethene (TCE) while considering redox conditions and the heterogeneous clay till system (clay till matrix, fractures and sand stringers). The model is tested on lab batch experiments and applied to describe sediment core samples from a TCE-contaminated site. Model simulations compare favorably to field observations and demonstrate that dechlorination may be limited to narrow bioactive zones in the clay matrix around fractures and sand stringers. Field scale simulations show that the injected donor is expected to be depleted after 5 years, and that without donor re-injection contaminant rebound will occur in the high permeability zones and the mass removal will stall at 18%. Long remediation timeframes, if dechlorination is limited to narrow bioactive zones, and the need for additional donor injections to maintain dechlorination activity may limit the efficiency of ERD in low-permeability media. Future work should address the dynamics of the bioactive zones, which is essential to understand for predictions of long term mass removal.

  16. Ligand-enhanced electrokinetic remediation of metal-contaminated marine sediments with high acid buffering capacity.

    PubMed

    Masi, Matteo; Iannelli, Renato; Losito, Gabriella

    2016-06-01

    The suitability of electrokinetic remediation for removing heavy metals from dredged marine sediments with high acid buffering capacity was investigated. Laboratory-scale electrokinetic remediation experiments were carried out by applying two different voltage gradients to the sediment (0.5 and 0.8 V/cm) while circulating water or two different chelating agents at the electrode compartments. Tap water, 0.1 M citric acid and 0.1 M ethylenediaminetetraacetic acid (EDTA) solutions were used respectively. The investigated metals were Zn, Pb, V, Ni and Cu. In the unenhanced experiment, the acid front could not propagate due to the high acid buffering capacity of the sediments; the production of OH(-) ions at the cathode resulted in a high-pH environment causing the precipitation of CaCO3 and metal hydroxides. The use of citric acid prevented the formation of precipitates, but solubilisation and mobilisation of metal species were not sufficiently achieved. Metal removal was relevant when EDTA was used as the conditioning agent, and the electric potential was raised up to 0.8 V/cm. EDTA led to the formation of negatively charged complexes with metals which migrated towards the anode compartment by electromigration. This result shows that metal removal from sediments with high acid buffering capacity may be achieved by enhancing the electrokinetic process by EDTA addition when the acidification of the medium is not economically and/or environmentally sustainable. PMID:26490900

  17. Conductivity reduction due to emulsification during surfactant enhanced-aquifer remediation. 1. Emulsion transport.

    PubMed

    Jain, Vivek; Demond, Avery H

    2002-12-15

    Surfactant-enhanced aquifer remediation (SEAR) is a promising technology for the remediation of subsurface zones contaminated with organic liquids. To ensure the success of SEAR, the potential reduction in hydraulic conductivity must be evaluated. The objective of this study was to examine the process of conductivity reduction due to the transport of an emulsion, generated by mixing tetrachloroethylene with 4% solutions of two nonionic surfactants, in packed beds of sand-sized silica particles. The injection of the emulsion resulted in a 75-85% reduction in conductivity, depending on the properties of the surfactant and the porous medium. The greater viscosity of the emulsion relative to that of water accounted for about 25% of the reduction. The remainder was attributed to the clogging of the porous medium by the emulsion. The relative sizes of the emulsion droplets and the packed bed's pores, coupled with measurements of zeta potential of the emulsion droplets and silica particles, suggested that multilayer deposition was the principal mechanism of clogging. This hypothesis was corroborated by direct observation of the emulsion transport process in a micromodel. To simulate the reduction in hydraulic conductivity in these systems accurately, it was necessary to modify the emulsion transport model by Soo and Radke to include the phenomena of viscosity variation and multilayering.

  18. Remediation of phthalates in river sediment by integrated enhanced bioremediation and electrokinetic process.

    PubMed

    Yang, Gordon C C; Huang, Sheng-Chih; Jen, Yu-Sheng; Tsai, Pei-Shin

    2016-05-01

    The objective of this study was to evaluate the feasibility of enhanced bioremediation coupling with electrokinetic process for promoting the growth of intrinsic microorganisms and removing phthalate esters (PAEs) from river sediment by adding an oxygen releasing compound (ORC). Test results are given as follows: Enhanced removal of PAEs was obtained by electrokinetics, through which the electroosmotic flow would render desorption of organic pollutants from sediment particles yielding an increased bioavailability. It was also found that the ORC injected into the sediment compartment not only would alleviate the pH value variation due to acid front and base front, but would be directly utilized as the carbon source and oxygen source for microbial growth resulting in an enhanced degradation of organic pollutants. However, injection of the ORC into the anode compartment could yield a lower degree of microbial growth due to the loss of ORC during the transport by EK. Through the analysis of molecular biotechnology it was found that both addition of an ORC and application of an external electric field can be beneficial to the growth of intrinsic microbial and abundance of microflora. In addition, the sequencing result showed that PAEs could be degraded by the following four strains: Flavobacterium sp., Bacillus sp., Pseudomonas sp., and Rhodococcus sp. The above findings confirm that coupling of enhanced bioremediation and electrokinetic process could be a viable remediation technology to treat PAEs-contaminated river sediment. PMID:26733014

  19. Hydraulic fracturing to enhance the remediation of DNAPL in low permeability soils

    SciTech Connect

    Murdoch, L.; Slack, B.

    1996-08-01

    Meager rates of fluid flow are a major obstacle to in situ remediation of low permeability soils. This paper describes methods designed to avoid that obstacle by creating fractures and filling them with sand to increase well discharge and change paths of fluid flow in soil. Gently dipping fractures 10 m in maximum dimension and 1 to 2 cm thick can be created in some contaminated soils at depths of a few in or greater. Hydraulic fractures can also be used to create electrically conductive layers or to deliver granules of chemically or biologically active compounds that will degrade contaminants in place. Benefits of applying hydraulic fractures to DNAPL recovery include rates of fluid recovery, enhancing upward gradients to improve hydrodynamic stabilization, forming flat-lying reactive curtains to intersect compounds moving downward, or improving the performance of electrokinetics intended to recover compounds dissolved in water. 30 refs., 7 figs., 1 tab.

  20. Use of Historical Pump-and-Treat Data to Enhance Site Characterization and Remediation Performance Assessment.

    PubMed

    Brusseau, Mark L

    2013-10-01

    Groundwater withdrawal and contaminant concentration data are routinely collected for pump-and-treat operations conducted at hazardous waste sites. These data sets can be mined to produce a wealth of information to support enhanced site characterization, optimization of remedial system operations, and improved decision making regarding long-term site management and closure. Methods that may be used to analyze and interpret pump-and-treat data to produce such assessments are presented, along with a brief illustration of their application to a site. The results presented herein illustrate that comprehensive analysis of pump-and-treat data is a powerful, cost-effective method for providing higher-resolution, value-added characterization of contaminated sites.

  1. Enhanced Amendment Delivery to Subsurface Using Shear Thinning Fluid and Aqueous Foam for Metal, Radionuclide, and NAPL Remediation

    NASA Astrophysics Data System (ADS)

    Zhong, L.; Szecsody, J.; Li, X.; Oostrom, M.; Truex, M.

    2010-12-01

    In many contamination sites, removal of contaminants by any active remediation efforts is not practical due to the high cost and technological limitations. Alternatively, in situ remediation is expected to be the most important remediation strategy. Delivery of reactive amendment to the contamination zone is essential for the reactions between the contaminants and remedial amendments to proceed in situ. It is a challenge to effectively deliver remedial amendment to the subsurface contamination source areas in both aquifer and vadose zone. In aquifer, heterogeneity induces fluid bypassing the low-permeability zones, resulting in certain contaminated areas inaccessible to the remedial amendment delivered by water injection, thus inhibiting the success of remedial operations. In vadose zone in situ remediation, conventional solution injection and infiltration for amendment delivery have difficulties to achieve successful lateral spreading and uniform distribution of the reactive media. These approaches also tend to displace highly mobile metal and radionuclide contaminants such as hexavalent chromium [Cr(VI)] and technetium (Tc-99), causing spreading of contaminations. Shear thinning fluid and aqueous foam can be applied to enhance the amendment delivery and improve in situ subsurface remediation efficiency under aquifer and vadose zone conditions, respectively. Column and 2-D flow cell experiments were conducted to demonstrate the enhanced delivery and improved remediation achieved by the application of shear thinning fluid and foam injection at the laboratory scale. Solutions of biopolymer xanthan gum were used as the shear thinning delivering fluids. Surfactant sodium lauryl ether sulfate (STEOL CS-330) was the foaming agent. The shear thinning fluid delivery (STFD) considerably improved the sweeping efficiency over a heterogeneous system and enhanced the non-aqueous liquid phase (NAPL) removal. The delivery of amendment into low-perm zones (LPZs) by STFD also

  2. Diversity and utilization of antimalarial ethnophytotherapeutic remedies among the Kikuyus (Central Kenya)

    PubMed Central

    Njoroge, Grace N; Bussmann, Rainer W

    2006-01-01

    Plants in Kenya are becoming increasingly important as sources of traditional medicines. The World Health Organization (WHO) has estimated that malaria kills about 2.7 million people every year, 90% of who are from Africa. Malaria continues to be a national concern in Kenya as it plays a major role in the high mortality rates being experienced currently. The use and miss-use of chloroquine to prevent and treat falciparium malaria has led to widespread appearance of chloroquine resistant parasites in Kenya and other tropical countries. These factors and the rising costs of non-chloroquine drugs have made the local people to turn to traditional remedies for management of this menace. This paper examines the current utilization of traditional plant medicines in managing malaria menace in Central Kenya. The results show both indigenous and introduced species are in use indicating traditional medicinal practices in this region are dynamic. In total 58 species in 54 genera and 33 families were identified. The family Rubiaceae was found to have the highest number of reported species. Use of the various taxa is compared between five districts within Central Province of Kenya. The commonest species in this pharmacopoeia are: Caesalpinia volkensii Harms, Strychnos henningsii Gilg, Ajuga remota Benth., Warbugia ugandensis Sprague and Olea europaea L. The first three species are used in all the five districts while the others are restricted in some of the districts. In 74% of the anti-malarial plant species reported in this study, the remedies are obtained in destructive manner and may need conservation measures to ensure sustainable utilization. The results of this study become a basis for selecting plants for further pharmacological and phytochemical studies in developing new and locally relevant anti-malarial agents. PMID:16451716

  3. Enhancement of electrokinetic remediation of arsenic spiked soil by chemical reagents.

    PubMed

    Yuan, Ching; Chiang, Tzu-Shing

    2008-03-21

    An enhanced electrokinetic remediation process for removal of arsenic, presented as As(V) form, from spiked soil has been investigated with groundwater (GW) and chemical reagents of cetylpyridinium chloride (CPC, a cationic surfactant), ethylenediaminetetraacetic acid (EDTA) and citric acid (CA) under potential gradient of 2.0-3.3V/cm for 5 days treatment. The removal efficiency of As(V) in EK-EDTA system was better than that in other two EK systems. As potential gradient increased from 2.0V/cm to 3.0V/cm, the removal efficiency of As(V) was increased from 35.4% to 44.8% in EK-EDTA system. It showed that the arsenic removal could be enhanced by selecting suitable chemical reagent and increasing potential gradient. The intensive of electroosmotic flow towards the cathode caused a significant retardation of electromigration of arsenic towards the anode. The quantity of As(V) collected in anode reservoir was 1.4-2.5 times greater than that in cathode reservoir for all EK systems. It implied that As(V) removal was directly related to the electromigration rather than electroosmosis mechanism in EK systems. A further investigation need to be conducted to achieve higher removal efficiency of As(V).

  4. Perchlorate and Nitrate Remediation Efficiency and Microbial Diversity in a Containerized Wetland Bioreactor

    SciTech Connect

    Jr., B D; Dibley, V; Pinkart, H; Legler, T

    2004-06-09

    We have developed a method to remove perchlorate (14 to 27 {micro}g/L) and nitrate (48 mg/L) from contaminated groundwater using a wetland bioreactor. The bioreactor has operated continuously in a remote field location for more than two years with a stable ecosystem of indigenous organisms. This study assesses the bioreactor for long-term perchlorate and nitrate remediation by evaluating influent and effluent groundwater for reduction-oxidation conditions and nitrate and perchlorate concentrations. Total community DNA was extracted and purified from 10-g sediment samples retrieved from vertical coring of the bioreactor during winter. Analysis by denaturing gradient gel electrophoresis of short, 16S rDNA, polymerase-chain-reaction products was used to identify dominant microorganisms. Bacteria genera identified were closely affiliated with bacteria widely distributed in soils, mud layers, and fresh water. Of the 17 dominant bands sequenced, most were gram negative and capable of aerobic or anaerobic respiration with nitrate as the terminal electron acceptor (Pseudomonas, Acinetobacter, Halomonas, and Nitrospira). Several identified genera (Rhizobium, Acinetobactor, and Xanthomonas) are capable of fixing atmospheric nitrogen into a combined form (ammonia) usable by host plants. Isolates were identified from the Proteobacteria class, known for the ability to reduce perchlorate. Initial bacterial assessments of sediments confirm the prevalence of facultative anaerobic bacteria capable of reducing perchlorate and nitrate in situ.

  5. Perchlorate and nitrate remediation efficiency and microbial diversity in a containerized wetland bioreactor.

    PubMed

    Krauter, Paula; Daily, Bill; Dibley, Valerie; Pinkart, Holly; Legler, Tina

    2005-01-01

    We have developed a method to remove perchlorate (14-27 microg/L) and nitrate (48 mg/L) from contaminated groundwater using a wetland bioreactor. The bioreactor has operated continuously in a remote field location for more than 2 yr with a stable ecosystem of indigenous organisms. This study assesses the bioreactorfor long-term perchlorate and nitrate remediation by evaluating influent and effluent groundwater for oxidation-reduction conditions and nitrate and perchlorate concentrations. Total community DNA was extracted and purified from 10-g sediment samples retrieved from vertical coring of the bioreactor during winter. Analysis by denaturing gradient gel electrophoresis of short, 16S rDNA, polymerase-chainreaction products was used to identify dominant microorganisms. Bacteria genera identified were closely affiliated with bacteria widely distributed in soils, mud layers, and fresh water. Of the 17 dominant bands sequenced, most were gram negative and capable of aerobic or anaerobic respiration with nitrate as the terminal electron acceptor (Pseudomonas, Acinetobacter, Halomonas, and Nitrospira). Several identified genera (Rhizobium, Acinetobactor, and Xanthomonas) are capable of fixing atmospheric nitrogen into a combined form (ammonia) usable by host plants. Isolates were identified from the Proteobacteria class, known for the ability to reduce perchlorate. Initial bacterial assessments of sediments confirm the prevalence of facultative anaerobic bacteria capable of reducing perchlorate and nitrate in situ.

  6. SETTING DATA QUALITY OBJECTIVES FOR THERMALLY ENHANCED, IN SITU REMEDIATION PROJECTS

    EPA Science Inventory

    The design and implementation of an in-situ technology requires an up-front and clear understanding of the remedial objectives of the technology application and the data that will be collected to track the progress of remediation and to assess the ultimate success of in-sit...

  7. Remediation of nonaqueous phase liquid polluted sites using surfactant-enhanced air sparging and soil vapor extraction.

    PubMed

    Qin, Chuan-Yu; Zhao, Yong-Sheng; Su, Yan; Zheng, Wei

    2013-02-01

    A two-dimensional laboratory sand tank was installed to study the remediation efficiency of surfactant-enhanced air sparging (-SEAS) coupled with soil vapor extraction (SVE) in nonaqueous phase liquid (NAPL) polluted sites. During initial stages of remediation, it was more reasonable to use conventional air sparging coupled with SVE. When most free NAPLs were removed and contaminant removal rate was maintained at a relatively low level, surfactant was added to the groundwater. During enhanced remediation, lower interfacial tension caused residual NAPLs in the porous media to slightly migrate, making the downstream contaminant concentration somewhat higher. The polluted area, however, was not more enlarged than before. The decrease in surface tension resulted in increased air saturation in the groundwater and the extent of the air influence zone. After 310 hours, 78.7% of the initial chlorobenzene mass had volatilized, 3.3% had migrated out of the sand profile, 17.5% was in the vadose zone, and 0.5% remained in the groundwater, thus revealing that SEAS/SVE can effectively improve the remediation of NAPL polluted sites.

  8. Electrokinetic-enhanced bioaugmentation for remediation of chlorinated solvents contaminated clay

    PubMed Central

    Mao, Xuhui; Wang, James; Ciblak, Ali; Cox, Evan E.; Riis, Charlotte; Terkelsen, Mads; Gent, David B.; Alshawabkeh, Akram N.

    2012-01-01

    Successful bioremediation of contaminated soils is controlled by the ability to deliver bioremediation additives, such as bacteria and/or nutrients, to the contaminated zone. Because hydraulic advection is not practical for delivery in clays, electrokinetic (EK) injection is an alternative for efficient and uniform delivery of bioremediation additive into low-permeability soil and heterogeneous deposits. EK–enhanced bioaugmentation for remediation of clays contaminated with chlorinated solvents is evaluated. Dehalococcoides (Dhc) bacterial strain and lactate ions are uniformly injected in contaminated clay and complete dechlorination of chlorinated ethene is observed in laboratory experiments. The injected bacteria can survive, grow, and promote effective dechlorination under EK conditions and after EK application. The distribution of Dhc within the clay suggests that electrokinetic transport of Dhc is primarily driven by electroosmosis. In addition to biodegradation due to bioaugmentation of Dhc, an EK-driven transport of chlorinated ethenes is observed in the clay, which accelerates cleanup of chlorinated ethenes from the anode side. Compared with conventional advection-based delivery, EK injection is significantly more effective forestablis hingmicrobial reductive dechlorination capacity in low-permeability soils. PMID:22365139

  9. Electrokinetic-enhanced bioaugmentation for remediation of chlorinated solvents contaminated clay.

    PubMed

    Mao, Xuhui; Wang, James; Ciblak, Ali; Cox, Evan E; Riis, Charlotte; Terkelsen, Mads; Gent, David B; Alshawabkeh, Akram N

    2012-04-30

    Successful bioremediation of contaminated soils is controlled by the ability to deliver bioremediation additives, such as bacteria and/or nutrients, to the contaminated zone. Because hydraulic advection is not practical for delivery in clays, electrokinetic (EK) injection is an alternative for efficient and uniform delivery of bioremediation additive into low-permeability soil and heterogeneous deposits. EK-enhanced bioaugmentation for remediation of clays contaminated with chlorinated solvents is evaluated. Dehalococcoides (Dhc) bacterial strain and lactate ions are uniformly injected in contaminated clay and complete dechlorination of chlorinated ethene is observed in laboratory experiments. The injected bacteria can survive, grow, and promote effective dechlorination under EK conditions and after EK application. The distribution of Dhc within the clay suggests that electrokinetic transport of Dhc is primarily driven by electroosmosis. In addition to biodegradation due to bioaugmentation of Dhc, an EK-driven transport of chlorinated ethenes is observed in the clay, which accelerates cleanup of chlorinated ethenes from the anode side. Compared with conventional advection-based delivery, EK injection is significantly more effective for establishing microbial reductive dechlorination capacity in low-permeability soils. PMID:22365139

  10. Laboratory investigations of enhanced sulfate reduction as a groundwater arsenic remediation strategy.

    PubMed

    Keimowitz, A R; Mailloux, B J; Cole, P; Stute, M; Simpson, H J; Chillrud, S N

    2007-10-01

    Landfills have the potential to mobilize arsenic via induction of reducing conditions in groundwater and subsequent desorption from or dissolution of arsenic-bearing iron phases. Laboratory incubation experiments were conducted with materials from a landfill where such processes are occurring. These experiments explored the potential for induced sulfate reduction to immobilize dissolved arsenic in situ. The native microbial community at this site reduced sulfate in the presence of added acetate. Acetate respiration and sulfate reduction were observed concurrent with dissolved iron concentrations initially increasing from 0.6 microM (0.03 mg L(-1)) to a maximum of 111 microM (6.1 mg L(-1)) and subsequently decreasing to 0.74 microM (0.04 mg L(-1)). Dissolved arsenic concentrations initially covaried with iron but subsequently increased again as sulfide accumulated, consistent with the formation of soluble thioarsenite complexes. Dissolved arsenic concentrations subsequently decreased again from a maximum of 2 microM (148 microg L(-1)) to 0.3 microM (22 microg L(-1)), consistent with formation of sulfide mineral phases or increased arsenic sorption at higher pH values. Disequilibrium processes may also explain this second arsenic peak. The maximum iron and arsenic concentrations observed in the lab represent conditions most equivalent to the in situ conditions. These findings indicate that enhanced sulfate reduction merits further study as a potential in situ groundwater arsenic remediation strategy at landfills and other sites with elevated arsenic in reducing groundwater.

  11. Developmental, Remedial, and Basic Skills: Diverse Programs and Approaches at Community Colleges

    ERIC Educational Resources Information Center

    Hagedorn, Linda Serra; Kuznetsova, Inna

    2016-01-01

    Community colleges have been challenged to increase their graduation, transfer, and general success rates. Because they serve the largest proportion of nontraditional students and students of color, their participation in programs to enhance the number of college graduates contributes to social equity and justice. One of the biggest obstacles has…

  12. Potential enhancements to addressing programmatic risk in the tank waste remediation system (TWRS) program

    SciTech Connect

    Brothers, A.; Fassbender, L.; Bilyard, G.; Levine, L.

    1996-04-01

    Pacific Northwest National Laboratory (PNNL) conducted a Tank Waste Remediation System (TWRS) Risk Management methodology development task. The objective of this task was to develop risk management methodology focused on (1) the use of programmatic risk information in making TWRS architecture selection decisions and (2) the identification/evaluation/selection of TWRS risk-handling actions. Methods for incorporating programmatic risk/uncertainty estimates into trade studies are provided for engineers/analysts. Methods for identifying, evaluating, and selecting risk-handling actions are provided for managers. The guidance provided in this report is designed to help decision-makers make difficult judgments. Current approaches to architecture selection decisions and identification/evaluation/selection of risk-handling actions are summarized. Three categories of sources of programmatic risk (parametric, external, and organizational) are examined. Multiple analytical approaches are presented to enhance the current alternative generation and analysis (AGA) and risk-handling procedures. Appendix A describes some commercially available risk management software tools and Appendix B provides a brief introduction to quantification of risk attitudes. The report provides three levels of analysis for enhancing the AGA Procedure: (1) qualitative discussion coupled with estimated uncertainty ranges for scores in the alternatives-by-criteria matrix; (2) formal elicitation of probability distributions for the alternative scores; and (3) a formal, more structured, comprehensive risk analysis. A framework is also presented for using the AGA programmatic risk analysis results in making better decisions. The report also presents two levels of analysis for evaluation and selection of risk-handling actions: (1) qualitative analysis and judgmental rankings of alternative actions, and (2) Simple Multi-Attribute Rating Technique (SMART).

  13. Meaningful Engagement to Enhance Diversity: Broadened Impact Actualized

    NASA Astrophysics Data System (ADS)

    Whitney, V. W.; Pyrtle, A. J.

    2008-12-01

    The MS PHD'S Professional Development Program was established by and for UR/US populations to facilitate increased and sustained participation within the Earth system science community. MS PHD'S is jointly funded by NSF and NASA. Fourteen (14) minority Earth system scientists served as Program mentors and one- hundred fifteen (115) minority and non-minority scientists served as Meeting Mentors to student participants. Representatives from fifty-six (56) agencies and institutions provided support and exposure to MS PHD'S student participants. Two hundred fifty-eight (258) highly qualified UR/US students completed on-line applications to participate in the MS PHD'S Professional Development Program. Because of funding limitations, slightly fewer than 50% of the applicants were selected to participate. One-hundred twenty-six (126) undergraduate and graduate students from 26 states and Puerto Rico participated in the MS PHD'S program. Sixty-eight (68) MS PHD'S student participants self-identified as African American; thirty-four (34) as Puerto Rican; nine (9) as Hispanic/Mexican American, ten (10) as Native American and one (1) each as African, Asian, Pacific Islander, Hispanic and Multi-Ethnic. During the five year span of MS PHD'S programming, sixteen (16) student participants completed BS degrees, twelve (12) completed MS degrees and ten (10) completed the Doctoral degrees. How did MS PHD'S establish meaningful engagement to enhance diversity within the Earth system science community? This case study reveals replicable processes and constructs to enhance the quality of meaningful collaboration and engagement. In addition, the study addresses frequently asked questions (FAQ's) on outreach, recruitment, engagement, retention and success of students from underrepresented populations within diversity-focused programs.

  14. Electrokinetic-Enhanced Remediation of Phenanthrene-Contaminated Soil Combined with Sphingomonas sp. GY2B and Biosurfactant.

    PubMed

    Lin, Weijia; Guo, Chuling; Zhang, Hui; Liang, Xujun; Wei, Yanfu; Lu, Guining; Dang, Zhi

    2016-04-01

    Electrokinetic-microbial remediation (EMR) has emerged as a promising option for the removal of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils. The aim of this study was to enhance degradation of phenanthrene (Phe)-contaminated soils using EMR combined with biosurfactants. The electrokinetic (EK) remediation, combined with Phe-degrading Sphingomonas sp. GY2B, and biosurfactant obtained by fermentation of Pseudomonas sp. MZ01, degraded Phe in the soil with an efficiency of up to 65.1 % at the anode, 49.9 % at the cathode after 5 days of the treatment. The presence of biosurfactants, electricity, and a neutral electrolyte stimulated the growth of the degrading bacteria as shown by a rapid increase in microbial biomass with time. The electrical conductivity and pH changed little during the course of the treatment, which benefitted the growth of microorganisms and the remediation of Phe-contaminated soil. The EMR system with the addition of biosurfactant had the highest Phe removal, demonstrating the biosurfactant may enhance the bioavailability of Phe and the interaction with the microorganism. This study suggests that the EMR combined with biosurfactants can be used to enhance in situ bioremediation of PAH-contaminated soils. PMID:26683200

  15. Green remediation: enhanced reductive dechlorination using recycled rinse water as bioremediation substrate

    SciTech Connect

    Dawson, Gaynor; McKeon, Tom

    2007-07-01

    Enhanced reductive dechlorination (ERD) has rapidly become a remedy of choice for use on chlorinated solvent contamination when site conditions allow. With this approach, solutions of an organic substrate are injected into the affected aquifer to stimulate biological growth and the resultant production of reducing conditions in the target zone. Under the reducing conditions, hydrogen is produced and ultimately replaces chlorine atoms on the contaminant molecule causing sequential dechlorination. Under suitable conditions the process continues until the parent hydrocarbon precursor is produced, such as the complete dechlorination of trichloroethylene (TCE) to ethene. The process is optimized by use of a substrate that maximizes hydrogen production per unit cost. When natural biota are not present to promote the desired degradation, inoculates can be added with the substrate. The in-situ method both reduces cost and accelerates cleanup. Successful applications have been extended from the most common chlorinated compounds perchloroethylene (PCE) and TCE and related products of degradation, to perchlorate, and even explosives such as RDX and trinitrotoluene on which nitrates are attacked in lieu of chloride. In recent work, the process has been further improved through use of beverage industry wastewaters that are available at little or no cost. With material cost removed from the equation, applications can maximize the substrate loading without significantly increasing total cost. The extra substrate loading both accelerates reaction rates and extends the period of time over which reducing conditions are maintained. In some cases, the presence of other organic matter in addition to simple sugars provides for longer performance times of individual injections, thereby working in a fashion similar to emulsified vegetable oil. The paper discusses results of applications at three different sites contaminated with chlorinated ethylenes. The applications have included

  16. [Continuous remediation of heavy metal contaminated soil by co-cropping system enhanced with chelator].

    PubMed

    Wei, Ze-Bin; Guo, Xiao-Fang; Wu, Qi-Tang; Long, Xin-Xian

    2014-11-01

    In order to elucidate the continuous effectiveness of co-cropping system coupling with chelator enhancement in remediating heavy metal contaminated soils and its environmental risk towards underground water, soil lysimeter (0.9 m x 0.9 m x 0.9 m) experiments were conducted using a paddy soil affected by Pb and Zn mining in Lechang district of Guangdong Province, 7 successive crops were conducted for about 2.5 years. The treatments included mono-crop of Sedum alfredii Hance (Zn and Cd hyperaccumulator), mono-crop of corn (Zea mays, cv. Yunshi-5, a low-accumulating cultivar), co-crop of S. alfredii and corn, and co-crop + MC (Mixture of Chelators, comprised of citric acid, monosodium glutamate waste liquid, EDTA and KCI with molar ratio of 10: 1:2:3 at the concentration of 5 mmol x kg(-1) soil). The changes of heavy metal concentrations in plants, soil and underground water were monitored. Results showed that the co-cropping system was suitable only in spring-summer seasons and significantly increased Zn and Cd phytoextraction. In autumn-winter seasons, the growth of S. alfredii and its phytoextraction of Zn and Cd were reduced by co-cropping and MC application. In total, the mono-crops of S. alfredii recorded a highest phytoextraction of Zn and Cd. However, the greatest reduction of soil Zn, Cd and Pb was observed with the co-crop + MC treatment, the reduction rates were 28%, 50%, and 22%, respectively, relative to the initial soil metal content. The reduction of this treatment was mainly attributed to the downwards leaching of metals to the subsoil caused by MC application. The continuous monitoring of leachates during 2. 5 year's experiment also revealed that the addition of MC increased heavy metal concentrations in the leaching water, but they did not significantly exceed the III grade limits of the underground water standard of China.

  17. Stand structural diversity rather than species diversity enhances aboveground carbon storage in secondary subtropical forests in Eastern China

    NASA Astrophysics Data System (ADS)

    Ali, Arshad; Yan, En-Rong; Chen, Han Y. H.; Chang, Scott X.; Zhao, Yan-Tao; Yang, Xiao-Dong; Xu, Ming-Shan

    2016-08-01

    height diversity through silvicultural operations might constitute an effective approach for enhancing aboveground C storage in these forests.

  18. DEMONSTRATION OF PILOT-SCALE PERVAPORATION SYSTEMS FOR VOLATILE ORGANIC COMPOUND REMOVAL FROM A SURFACTANT ENHANCED AQUIFER REMEDIATION FLUID. II. HOLLOW FIBER MEMBRANE MODULES

    EPA Science Inventory

    Pilot-scale demonstration of pervaporation-based removal of volatile organic compounds from a surfactant enhanced aquifer remediation (SEAR) fluid has been conducted at USEPA's Test & Evaluation Facility using hollow fiber membrane modules. The membranes consisted of microporous...

  19. Development, Discouragement, or Diversion? New Evidence on the Effects of College Remediation. NBER Working Paper No. 18328

    ERIC Educational Resources Information Center

    Scott-Clayton, Judith; Rodriguez, Olga

    2012-01-01

    Half of all college students take at least one remedial course as part of their postsecondary experience, despite mixed evidence on the effectiveness of this intervention. Using a regression-discontinuity design with data from a large urban community college system, we extend the research on remediation in three ways. First, we articulate three…

  20. Calreticulin Enhances Porcine Wound Repair by Diverse Biological Effects

    PubMed Central

    Nanney, Lillian B.; Woodrell, Christopher D.; Greives, Mathew R.; Cardwell, Nancy L.; Pollins, Alonda C.; Bancroft, Tara A.; Chesser, Adrianne; Michalak, Marek; Rahman, Mohammad; Siebert, John W.; Gold, Leslie I.

    2008-01-01

    Extracellular functions of the endoplasmic reticulum chaperone protein calreticulin (CRT) are emerging. Here we show novel roles for exogenous CRT in both cutaneous wound healing and diverse processes associated with repair. Compared with platelet-derived growth factor-BB-treated controls, topical application of CRT to porcine excisional wounds enhanced the rate of wound re-epithelialization. In both normal and steroid-impaired pigs, CRT increased granulation tissue formation. Immunohistochemical analyses of the wounds 5 and 10 days after injury revealed marked up-regulation of transforming growth factor-β3 (a key regulator of wound healing), a threefold increase in macrophage influx, and an increase in the cellular proliferation of basal keratinocytes of the new epidermis and of cells of the neodermis. In vitro studies confirmed that CRT induced a greater than twofold increase in the cellular proliferation of primary human keratinocytes, fibroblasts, and microvascular endothelial cells (with 100 pg/ml, 100 ng/ml, and 1.0 pg/ml, respectively). Moreover, using a scratch plate assay, CRT maximally induced the cellular migration of keratinocytes and fibroblasts (with 10 pg/ml and 1 ng/ml, respectively). In addition, CRT induced concentration-dependent migration of keratinocytes, fibroblasts macrophages, and monocytes in chamber assays. These in vitro bioactivities provide mechanistic support for the positive biological effects of CRT observed on both the epidermis and dermis of wounds in vivo, underscoring a significant role for CRT in the repair of cutaneous wounds. PMID:18753412

  1. Low-concentration tailing and subsequent quicklime-enhanced remediation of volatile chlorinated hydrocarbon-contaminated soils by mechanical soil aeration.

    PubMed

    Ma, Yan; Du, Xiaoming; Shi, Yi; Xu, Zhu; Fang, Jidun; Li, Zheng; Li, Fasheng

    2015-02-01

    Mechanical soil aeration has long been regarded as an effective ex-situ remediation technique and as suitable for remediation of large-scale sites contaminated by volatile organic compounds (VOCs) at low cost. However, it has been reported that the removal efficiency of VOCs from soil is relatively low in the late stages of remediation, in association with tailing. Tailing may extend the remediation time required; moreover, it typically results in the presence of contaminants residues at levels far exceeding regulations. In this context, the present study aimed to discuss the tailing that occurs during the process of remediation of soils contaminated artificially with volatile chlorinated hydrocarbons (VCHs) and to assess possible quicklime-enhanced removal mechanisms. The results revealed the following conclusions. First, temperature and aeration rate can be important controls on both the timing of appearance of tailing and the levels of residual contaminants. Furthermore, the addition of quicklime to soil during tailing can reduce the residual concentrations rapidly to below the remedial target values required for site remediation. Finally, mechanical soil aeration can be enhanced using quicklime, which can improve the volatilization of VCHs via increasing soil temperature, reducing soil moisture, and enhancing soil permeability. Our findings give a basic understanding to the elimination of the tailing in the application of mechanical soil aeration, particularly for VOCs-contaminated soils.

  2. Technology To Enhance Special Education: Remediation of Problems in Logical Thinking and Memory. Final Report.

    ERIC Educational Resources Information Center

    Cavalier, Al; And Others

    A federally sponsored project was designed to incorporate a memory-assessment task and a memory strategy into a computer-based instructional system for assessing and assisting in remediating basic memory-processing and metacognitive deficiencies. The project resulted in an instructional system for school-aged children and youth with mild to…

  3. Development of a Diagnostic and Remedial Learning System Based on an Enhanced Concept--Effect Model

    ERIC Educational Resources Information Center

    Panjaburees, Patcharin; Triampo, Wannapong; Hwang, Gwo-Jen; Chuedoung, Meechoke; Triampo, Darapond

    2013-01-01

    With the rapid advances in computer technology during recent years, researchers have demonstrated the pivotal influences of computer-assisted diagnostic systems on student learning performance improvement. This research aims to develop a Diagnostic and Remedial Learning System (DRLS) for an algebra course in a Thai lower secondary school context…

  4. 77 FR 76627 - Enhanced Prudential Standards and Early Remediation Requirements for Foreign Banking...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... limits, stress test requirements, and a debt-to- equity limit for companies that the Financial Stability..., Senior Attorney, (202) 452-3005, Legal Division. Debt-to-Equity Limits for Certain Covered Companies... IX. Debt-to-Equity Limits X. Early Remediation XI. Administrative Law Matters I. Introduction...

  5. Part 2: A field study of enhanced remediation of Toluene in the vadose zone using a nutrient solution

    USGS Publications Warehouse

    Tindall, J.A.; Weeks, E.P.; Friedel, M.

    2005-01-01

    The objective of this study was to test the effectiveness of a nitrate-rich nutrient solution and hydrogen peroxide (H2O2) to enhance in-situ microbial remediation of toluene in the unsaturated zone. Three sand-filled plots were tested in three phases (each phase lasting approximately 2 weeks). During the control phase, toluene was applied uniformly via sprinkler irrigation. Passive remediation was allowed to occur during this phase. A modified Hoagland nutrient solution, concentrated in 150 L of water, was tested during the second phase. The final phase involved addition of 230 moles of H2O2 in 150 L of water to increase the available oxygen needed for aerobic biodegradation. During the first phase, measured toluene concentrations in soil gas were reduced from 120 ppm to 25 ppm in 14 days. After the addition of nutrients during the second phase, concentrations were reduced from 90 ppm to about 8 ppm within 14 days, and for the third phase (H 2O2), toluene concentrations were about 1 ppm after only 5 days. Initial results suggest that this method could be an effective means of remediating a contaminated site, directly after a BTEX spill, without the intrusiveness and high cost of other abatement technologies such as bioventing or soil-vapor extraction. However, further tests need to be completed to determine the effect of each of the BTEX components. ?? Springer 2005.

  6. Enhanced Remediation of Toluene in the Vadose Zone via a Nitrate-Rich Nutrient Solution: Field Study

    NASA Astrophysics Data System (ADS)

    Tindall, J. A.; Friedel, M. J.

    2003-12-01

    The objective of this study was to test the effectiveness of nitrate-rich nutrient solutions and hydrogen peroxide (H202) to enhance in-situ microbial remediation of toluene. Three sand filled plots (2 m2 surface area and 1.5 meters deep) were tested in three phases (each phase lasting approximately 2 weeks). During each phase, toluene (21.6 mol as an emulsion in 50L of water) was applied uniformly via sprinkler irrigation. Passive remediation was allowed to occur during the first (control) phase. A nutrient solution (modified Hoagland), concentrated in 40L of water, was tested during the second phase. The final phase involved addition of 230 moles of H202 in 50L of water to increase the available oxygen needed for aerobic biodegradation. During the first phase, toluene concentrations in soil gas were reduced from 120 ppm to 25 ppm in 14 days. After the addition of nutrients during the second phase, concentrations were reduced from 90 ppm to about 8 ppm within 14 days, and for the third phase (H202), toluene concentrations were about 1 ppm after only five days. Initial results suggest that this method could be an effective means of remediating a contaminated site, directly after a BTEX spill, without the intrusiveness and high cost of other abatement technologies such as bioventing and soil vapor extraction. However, further tests need to be completed to determine the effect of each of the BTEX components.

  7. Pilot-scale demonstration of cyclodextrin as a solubility-enhancement agent for remediation of a tetrachloroethene-contaminated aquifer.

    PubMed

    Tick, Geoffrey R; Lourenso, Fara; Wood, A Lynn; Brusseau, Mark L

    2003-12-15

    The limitations associated with conventional pump and treat technology have generated interest in using enhanced in-situ flushing as an alternative for remediating source zones contaminated with immiscible liquid. This research investigates the effectiveness of cyclodextrin as a solubility-enhancement agent to enhance the removal of tetrachloroethene (PCE) from a physically isolated section of an aquifer. An important component of this project was the implementation of reagent recovery and reuse. This field experiment presented the rare opportunity, under strict regulatory guidance, to inject PCE into the surficial aquifer cell created with two sets of sheet piles driven into an underlying clay unit. The well-controlled conditions specific to this experiment allowed quantification of mass balances, which is problematic for many contaminated field sites. The fact that mass balances can be obtained provides the ability to determine remediation effectiveness with unusual accuracy for a field project. The saturated zone within the test cell was flushed with a 15 wt % cyclodextrin solution. The cyclodextrin solution increased the aqueous concentration of PCE in the extraction-well effluent to as much as 22 times the concentrations obtained during the water flush conducted prior to the complexing sugar flush (CSF). The seven pore-volume CSF removed the equivalent of approximately 33 L of PCE from the subsurface. This equates to 48% of the total initial mass, based on the volume of PCE present prior to the CSF (68.6 L). Conversely, the seven pore-volume water flush conducted prior to the CSF removed the equivalent of 2.7 L of PCE. The use of cyclodextrin as a flushing agent, especially in a recycling configuration, appears to hold promise for successful remediation of chlorinated-solvent-contaminated source zones.

  8. Simulation-based process optimization for surfactant-enhanced aquifer remediation at heterogeneous DNAPL-contaminated sites.

    PubMed

    Qin, X S; Huang, G H; Chakma, A; Chen, B; Zeng, G M

    2007-08-01

    Widespread use of dense non-aqueous phase liquids (DNAPLs) such as TCE and PCE has resulted in contamination of enormous valuable groundwater resources and become high-priority environmental problems. However, experiences from the past decades have demonstrated that DNAPL-contaminated sites were difficult to investigate and challenging to remediate. In this study, a simulation-based process optimization system was developed through integrating a multidimensional simulator, a multivariate statistical tool and an optimization model within a general framework for supporting decisions of surfactant-enhanced aquifer remediation (SEAR). A 3D multiphase and multi-component subsurface model was first provided to simulate SEAR process; dual-response surface models were then established to build a bridge between remediation actions and system performance; a nonlinear optimization model was then formulated for identifying optimal operating conditions for SEAR operations. The results in simulating a typical PCE spill event and the associated SEAR remediation operations in a heterogeneous subsurface indicated that SEAR would be capable of cleaning up the contaminated aquifer with improved efficiencies and cost-effectiveness compared with direct pump-and-treat actions. The regression-analysis results demonstrated that the proposed dual-response surface models were able to predict system responses under given operating conditions. The optimization results demonstrated that the developed simulation-optimization approach was effective in seeking cost-effective SEAR strategies for DNAPL-contaminated sites. With the developed method, optimum operation conditions under various environmental and economic considerations could be compiled into a database that would supports further studies of on-site process-control with injection and extraction rates being the main control variables.

  9. Experimental canopy removal enhances diversity of vernal pond amphibians.

    PubMed

    Skelly, David K; Bolden, Susan R; Freidenburg, L Kealoha

    2014-03-01

    Vernal ponds are often treated as protected environments receiving special regulation and management. Within the landscapes where they are found, forest vegetation frequently dominates surrounding uplands and can grow to overtop and shade pond basins. Two bodies of research offer differing views of the role of forest canopy for vernal pond systems. Studies of landscape conversion suggest that removing forest overstory within uplands can cause local extinctions of amphibians by altering terrestrial habitat or hindering movement. Studies of canopy above pond basins imply an opposite relationship; encroachment of overstory vegetation can be associated with local extinctions potentially via changes in light, thermal, and food resource environments. Unresolved uncertainties about the role of forest canopy reveal significant gaps in our understanding of wetland species distributions and dynamics. Any misunderstanding of canopy influences is simultaneously important to managers because current practices emphasize promoting or conserving vegetation growth particularly within buffers immediately adjacent to ponds. We evaluated this apparent contradiction by conducting a landscape-scale, long-term experiment using 14 natural vernal ponds. Tree felling at six manipulated ponds was limited in spatial scope but was nevertheless effective in increasing water temperature. Compared with eight control ponds, manipulated ponds maintained more amphibian species during five years post-manipulation. There was little evidence that any species was negatively influenced, and the reproductive effort of species for which we estimated egg inputs maintained pretreatment population densities in manipulated compared with control ponds. Overall, our experiment shows that a carefully circumscribed reduction of overhead forest canopy can enhance the capacity of vernal ponds to support wildlife diversity and suggests a scale dependence of canopy influences on amphibians. These findings have

  10. Garlic, from Remedy to Stimulant: Evaluation of Antifungal Potential Reveals Diversity in Phytoalexin Allicin Content among Garlic Cultivars; Allicin Containing Aqueous Garlic Extracts Trigger Antioxidants in Cucumber.

    PubMed

    Hayat, Sikandar; Cheng, Zhihui; Ahmad, Husain; Ali, Muhammad; Chen, Xuejin; Wang, Mengyi

    2016-01-01

    Garlic has the charisma of a potent remedy and holds its repute of a therapeutic panacea since the dawn of civilization. An integrated approach was adopted to evaluate the genetic diversity among Chinese garlic cultivars for their antifungal potency as well as allicin content distribution and, furthermore; a bioassay was performed to study the bio-stimulation mechanism of aqueous garlic extracts (AGE) in the growth and physiology of cucumber (Cucumis sativus). Initially, 28 garlic cultivars were evaluated against four kinds of phytopathogenic fungi; Fusarium oxysporum, Botrytis cinerea, Verticillium dahliae and Phytophthora capsici, respectively. A capricious antifungal potential among the selected garlic cultivars was observed. HPLC fingerprinting and quantification confirmed diversity in allicin abundance among the selected cultivars. Cultivar G025, G064, and G074 had the highest allicin content of 3.98, 3.7, and 3.66 mg g(-1), respectively, whereas G110 was found to have lowest allicin content of 0.66 mg g(-1). Cluster analysis revealed three groups on the basis of antifungal activity and allicin content among the garlic cultivars. Cultivar G025, G2011-4, and G110 were further evaluated to authenticate the findings through different solvents and shelf life duration and G025 had the strongest antifungal activity in all conditions. minimum inhibitory concentration and minimum fungicidal concentration of Allicin aqueous standard (AAS) and AGE showed significant role of allicin as primary antifungal substance of AGE. Leaf disk bioassay against P. capsici and V. dahliae to comparatively study direct action of AGE and AAS during infection process employing eggplant and pepper leaves showed a significant reduction in infection percentage. To study the bioactivity of AGE, a bioassay was performed using cucumber seedlings and results revealed that AGE is biologically active inside cucumber seedlings and alters the defense mechanism of the plant probably activating

  11. Garlic, from Remedy to Stimulant: Evaluation of Antifungal Potential Reveals Diversity in Phytoalexin Allicin Content among Garlic Cultivars; Allicin Containing Aqueous Garlic Extracts Trigger Antioxidants in Cucumber

    PubMed Central

    Hayat, Sikandar; Cheng, Zhihui; Ahmad, Husain; Ali, Muhammad; Chen, Xuejin; Wang, Mengyi

    2016-01-01

    Garlic has the charisma of a potent remedy and holds its repute of a therapeutic panacea since the dawn of civilization. An integrated approach was adopted to evaluate the genetic diversity among Chinese garlic cultivars for their antifungal potency as well as allicin content distribution and, furthermore; a bioassay was performed to study the bio-stimulation mechanism of aqueous garlic extracts (AGE) in the growth and physiology of cucumber (Cucumis sativus). Initially, 28 garlic cultivars were evaluated against four kinds of phytopathogenic fungi; Fusarium oxysporum, Botrytis cinerea, Verticillium dahliae and Phytophthora capsici, respectively. A capricious antifungal potential among the selected garlic cultivars was observed. HPLC fingerprinting and quantification confirmed diversity in allicin abundance among the selected cultivars. Cultivar G025, G064, and G074 had the highest allicin content of 3.98, 3.7, and 3.66 mg g-1, respectively, whereas G110 was found to have lowest allicin content of 0.66 mg g-1. Cluster analysis revealed three groups on the basis of antifungal activity and allicin content among the garlic cultivars. Cultivar G025, G2011-4, and G110 were further evaluated to authenticate the findings through different solvents and shelf life duration and G025 had the strongest antifungal activity in all conditions. minimum inhibitory concentration and minimum fungicidal concentration of Allicin aqueous standard (AAS) and AGE showed significant role of allicin as primary antifungal substance of AGE. Leaf disk bioassay against P. capsici and V. dahliae to comparatively study direct action of AGE and AAS during infection process employing eggplant and pepper leaves showed a significant reduction in infection percentage. To study the bioactivity of AGE, a bioassay was performed using cucumber seedlings and results revealed that AGE is biologically active inside cucumber seedlings and alters the defense mechanism of the plant probably activating reactive

  12. Garlic, from Remedy to Stimulant: Evaluation of Antifungal Potential Reveals Diversity in Phytoalexin Allicin Content among Garlic Cultivars; Allicin Containing Aqueous Garlic Extracts Trigger Antioxidants in Cucumber

    PubMed Central

    Hayat, Sikandar; Cheng, Zhihui; Ahmad, Husain; Ali, Muhammad; Chen, Xuejin; Wang, Mengyi

    2016-01-01

    Garlic has the charisma of a potent remedy and holds its repute of a therapeutic panacea since the dawn of civilization. An integrated approach was adopted to evaluate the genetic diversity among Chinese garlic cultivars for their antifungal potency as well as allicin content distribution and, furthermore; a bioassay was performed to study the bio-stimulation mechanism of aqueous garlic extracts (AGE) in the growth and physiology of cucumber (Cucumis sativus). Initially, 28 garlic cultivars were evaluated against four kinds of phytopathogenic fungi; Fusarium oxysporum, Botrytis cinerea, Verticillium dahliae and Phytophthora capsici, respectively. A capricious antifungal potential among the selected garlic cultivars was observed. HPLC fingerprinting and quantification confirmed diversity in allicin abundance among the selected cultivars. Cultivar G025, G064, and G074 had the highest allicin content of 3.98, 3.7, and 3.66 mg g-1, respectively, whereas G110 was found to have lowest allicin content of 0.66 mg g-1. Cluster analysis revealed three groups on the basis of antifungal activity and allicin content among the garlic cultivars. Cultivar G025, G2011-4, and G110 were further evaluated to authenticate the findings through different solvents and shelf life duration and G025 had the strongest antifungal activity in all conditions. minimum inhibitory concentration and minimum fungicidal concentration of Allicin aqueous standard (AAS) and AGE showed significant role of allicin as primary antifungal substance of AGE. Leaf disk bioassay against P. capsici and V. dahliae to comparatively study direct action of AGE and AAS during infection process employing eggplant and pepper leaves showed a significant reduction in infection percentage. To study the bioactivity of AGE, a bioassay was performed using cucumber seedlings and results revealed that AGE is biologically active inside cucumber seedlings and alters the defense mechanism of the plant probably activating reactive

  13. Enhancing Diversity in Vocational Education. Information Series No. 351.

    ERIC Educational Resources Information Center

    Bowen, Blannie E.; Jackson, Gary B.

    Vocational education can play a significant role in achieving the ideals of a diverse society. Although workplace changes and global economics make vocational education essential, an increasingly diverse population includes groups that have not traditionally participated extensively in vocational education. Philosophical and attitudinal changes…

  14. Teacher Education's Responsibility to Address Diversity Issues: Enhancing Institutional Capacity.

    ERIC Educational Resources Information Center

    Melnick, Susan L.; Zeichner, Kenneth M.

    1998-01-01

    Preservice teachers must be prepared to address substantial student diversity and to educate all students to higher levels of understanding and competence. Many teacher educators are not competent to prepare new teachers in this area. Several approaches to handling institutional aspects of teacher education for diversity are discussed, noting…

  15. Geotechnical behaviour of low-permeability soils in surfactant-enhanced electrokinetic remediation.

    PubMed

    López-Vizcaíno, Rubén; Navarro, Vicente; Alonso, Juan; Yustres, Ángel; Cañizares, Pablo; Rodrigo, Manuel A; Sáez, Cristina

    2016-01-01

    Electrokinetic processes provide the basis of a range of very interesting techniques for the remediation of polluted soils. These techniques consist of the application of a current field in the soil that develops different transport mechanisms capable of mobilizing several types of pollutants. However, the use of these techniques could generate nondesirable effects related to the geomechanical behavior of the soil, reducing the effectiveness of the processes. In the case of the remediation of polluted soils with plasticity index higher than 35, an excessive shrinkage can be observed in remediation test. For this reason, the continued evaporation that takes place in the sample top can lead to the development of cracks, distorting the electrokinetic transport regime, and consequently, the development of the operation. On the other hand, when analyzing silty soils, in the surroundings of injection surfactant wells, high seepages can be generated that give rise to the development of piping processes. In this article methods are described to allow a reduction, or to even eliminate, both problems.

  16. Field Test of Enhanced Remedial Amendment Delivery Using a Shear-Thinning Fluid

    SciTech Connect

    Truex, Michael J.; Vermeul, Vincent R.; Adamson, David; Oostrom, Martinus; Zhong, Lirong; Mackley, Rob D.; Fritz, Brad G.; Horner, Jacob A.; Johnson, Timothy C.; Thomle, Jonathan N.; Newcomer, Darrell R.; Johnson, Christian D.; Rysz, Michal; Wietsma, Thomas W.; Newell, Charles J.

    2015-03-01

    Heterogeneity of hydraulic properties in aquifers may lead to contaminants residing in lower-permeability zones where it is difficult to deliver remediation amendments using conventional injection processes. The focus of this effort is to examine use of a shear-thinning fluid (STF) to improve the uniformity of remedial amendment distribution within a heterogeneous aquifer. Previous studies have demonstrated the significant potential of STFs for improving remedial amendment delivery in heterogeneous aquifers, but quantitative evaluation of these improvements from field applications are lacking. A field-scale test was conducted that compares data from successive injection of a tracer in water followed by injection of a tracer in a STF to evaluate the impact of the STF on tracer distribution uniformity in the presence of permeability contrasts within the targeted injection zone. Data from tracer breakthrough at multiple depth-discrete monitoring intervals and electrical resistivity tomography showed that inclusion of STF in the injection solution slowed movement in high-permeability pathways, improved delivery of amendment to low-permeability materials, and resulted in better uniformity in injected fluid distribution within the targeted treatment zone.

  17. Geotechnical behaviour of low-permeability soils in surfactant-enhanced electrokinetic remediation.

    PubMed

    López-Vizcaíno, Rubén; Navarro, Vicente; Alonso, Juan; Yustres, Ángel; Cañizares, Pablo; Rodrigo, Manuel A; Sáez, Cristina

    2016-01-01

    Electrokinetic processes provide the basis of a range of very interesting techniques for the remediation of polluted soils. These techniques consist of the application of a current field in the soil that develops different transport mechanisms capable of mobilizing several types of pollutants. However, the use of these techniques could generate nondesirable effects related to the geomechanical behavior of the soil, reducing the effectiveness of the processes. In the case of the remediation of polluted soils with plasticity index higher than 35, an excessive shrinkage can be observed in remediation test. For this reason, the continued evaporation that takes place in the sample top can lead to the development of cracks, distorting the electrokinetic transport regime, and consequently, the development of the operation. On the other hand, when analyzing silty soils, in the surroundings of injection surfactant wells, high seepages can be generated that give rise to the development of piping processes. In this article methods are described to allow a reduction, or to even eliminate, both problems. PMID:26488188

  18. Laboratory {open_quotes}proof of principle{close_quotes} investigation for the acoustically enhanced remediation technology

    SciTech Connect

    Iovenitti, J.L.; Spencer, J.W. Jr.; Hill, D.G.

    1995-10-01

    Weiss Associates is conducting a three phase program investigating the systematics of using acoustic excitation fields (AEFs) to enhance the in-situ remediation of contaminated soil and ground water under both saturated and unsaturated conditions: Phase I - Laboratory Scale Parametric Investigation; Phase II - Technology Scaling Study; and Phase III - Large Scale Field Tests. Phase I, the subject of this paper, consisted primarily of a laboratory proof of principle investigation. The field deployment and engineering viability of acoustically enhanced remediation (AER) technology was also examined. Phase II is a technology scaling study addressing the scale up between laboratory size samples on the order of inches, and the data required for field scale testing, on the order of hundreds of feet. Phase III will consist of field scale testing at an non-industrialized, non-contaminated site and at a contaminated site to validate the technology. Summarized herein are the results of the Phase I {open_quotes}proof-of-principle{close_quotes} investigation, and recommendations for Phase H. A general overview of AER technology along with the plan for the Phase I investigation was presented.

  19. Genetic diversity in honey bee colonies enhances productivity and fitness.

    PubMed

    Mattila, Heather R; Seeley, Thomas D

    2007-07-20

    Honey bee queens mate with many males, creating numerous patrilines within colonies that are genetically distinct. The effects of genetic diversity on colony productivity and long-term fitness are unknown. We show that swarms from genetically diverse colonies (15 patrilines per colony) founded new colonies faster than swarms from genetically uniform colonies (1 patriline per colony). Accumulated differences in foraging rates, food storage, and population growth led to impressive boosts in the fitness (i.e., drone production and winter survival) of genetically diverse colonies. These results further our understanding of the origins of polyandry in honey bees and its benefits for colony performance.

  20. Plant functional diversity enhances associations of soil fungal diversity with vegetation and soil in the restoration of semiarid sandy grassland.

    PubMed

    Zuo, Xiaoan; Wang, Shaokun; Lv, Peng; Zhou, Xin; Zhao, Xueyong; Zhang, Tonghui; Zhang, Jing

    2016-01-01

    The trait-based approach shows that plant functional diversity strongly affects ecosystem properties. However, few empirical studies show the relationship between soil fungal diversity and plant functional diversity in natural ecosystems. We investigated soil fungal diversity along a restoration gradient of sandy grassland (mobile dune, semifixed dune, fixed dune, and grassland) in Horqin Sand Land, northern China, using the denaturing gradient gel electrophoresis of 18S rRNA and gene sequencing. We also examined associations of soil fungal diversity with plant functional diversity reflected by the dominant species' traits in community (community-weighted mean, CWM) and the dispersion of functional trait values (FD is). We further used the structure equation model (SEM) to evaluate how plant richness, biomass, functional diversity, and soil properties affect soil fungal diversity in sandy grassland restoration. Soil fungal richness in mobile dune and semifixed dune was markedly lower than those of fixed dune and grassland (P < 0.05). Soil fungal richness was positively associated with plant richness, biomass, CWM plant height, and soil gradient aggregated from the principal component analysis, but SEM results showed that plant richness and CWM plant height determined by soil properties were the main factors exerting direct effects. Soil gradient increased fungal richness through indirect effect on vegetation rather than direct effect. The negative indirect effect of FDis on soil fungal richness was through its effect on plant biomass. Our final SEM model based on plant functional diversity explained nearly 70% variances of soil fungal richness. Strong association of soil fungal richness with the dominant species in the community supported the mass ratio hypothesis. Our results clearly highlight the role of plant functional diversity in enhancing associations of soil fungal diversity with community structure and soil properties in sandy grassland ecosystems.

  1. Teacher Education for Cultural Diversity: Enhancing the Capacity of Teacher Education Institutions To Address Diversity Issues.

    ERIC Educational Resources Information Center

    Melnick, Susan L.; Zeichner, Kenneth M.

    This document reports on portions of a study on "Teacher Education for Diversity" in progress since 1990. The overall study includes an ongoing analysis of relevant literature, which has generated a conceptual framework describing the range of existing positions on teacher education for cultural diversity. The study includes the development of…

  2. Enhanced electrokinetic (E/K) remediation on copper contaminated soil by CFW (carbonized foods waste).

    PubMed

    Han, Jung-Geun; Hong, Ki-Kwon; Kim, Young-Woong; Lee, Jong-Young

    2010-05-15

    The E/K remediation method is presented to purify low permeable contaminated soils due to Cu(2+), and carbonized foods waste (CFW) was used as a permeable reactive barrier (PRB) material. For adsorption and precipitation of the Cu(2+) in the PRB during its motion, PRB was installed in a zone of rapidly changing pH values. The adsorption efficiency of CFW used as PRB material was found to be 4-8 times more efficient than that of Zeolite. Throughout the experiment, a voltage slope of 1V/cm was implemented and acetic acid was injected on the anode to increase the remediation efficiency. The electrode exchange was executed to more completely remove precipitated heavy metals in the vicinity of the cathode. The majority of Cu(2+) was adsorbed or sedimented by CFW prior to the exchange of the electrode, and the remaining quantity of precipitated Cu(2+) on the cathode had decreased with an increase in the operating time. Experiments of seven cases with different E/K operating times were performed, and the average removal ratios were 53.4-84.6%. The removal efficiencies for the majority of cases increased proportionally with an increase in the operating time. After the experiments were completed, the adsorbed Cu(2+) on CFW was 75-150 mg. This means that the role of CFW as the material in PRB for remediating heavy metals was confirmed. The cost of energies needed to remove Cu(2+), CFW, and acetic acid are estimated at US$ 13.3-40/m(3). PMID:20080337

  3. Increasing Academic Excellence and Enhancing Diversity Are Compatible Goals

    ERIC Educational Resources Information Center

    Sternberg, Robert Jeffrey

    2008-01-01

    It is possible to simultaneously increase academic excellence and diversity. This article describes how the theory of successful intelligence can be used to accomplish both of these goals. The theory postulates that intelligence comprises creative skills in generating novel ideas, analytical skills in discerning whether they are good ideas, and…

  4. Study Abroad: Enhanced Learning Experience in Cultural Diversity

    ERIC Educational Resources Information Center

    Jaoko, Japheth

    2010-01-01

    This paper examines how a study abroad experiential learning course in diversity provided a cultural immersion experience for a group of social work students from a small private university in central Kentucky. The students participated in a three-week international education experience in Kenya and reported this experience helped them become more…

  5. Professional Development Strategies to Enhance Diversity in the Geosciences

    ERIC Educational Resources Information Center

    Sherman-Morris, Kathleen; Rodgers, John C., III; McNeal, Karen S.; Brown, Michael E.; Dyer, Jamie L.

    2012-01-01

    Because of the historically low numbers of minorities in geoscience careers and college majors, an area of growing attention is how teacher professional development may be utilized to increase diversity in the geosciences (Pecore et al., 2007; Sedlock & Metzger, 2007). This paper examines teacher preferences for the timing, location and content of…

  6. Transforming an MFT Program: A Model for Enhancing Diversity

    ERIC Educational Resources Information Center

    McDowell, Teresa; Fang, Shi-Ruei; Brownlee, Kenya; Young, Cecilia Gomez; Khanna, Anchal

    2002-01-01

    Marriage and family therapy programs need to go beyond the typical practices of recruiting and retaining students of color. Marriage and family therapy educators must assume positions of leadership by transforming graduate programs to reflect a deep, active, systemic commitment to both diversity and social justice. In this article, we argue that…

  7. Development of Enhanced Remedial Techniques for Petroleum Fuel and Related Contaminants in Soil and Groundwater

    SciTech Connect

    Paul Fallgren

    2009-02-10

    Western Research Institute (WRI) in conjunction with Earth Tech and the U.S. Department of Energy (DOE) was to identify proper sites with soils and/or groundwater contaminated by petroleum constituents and MTBE. Biodegradation rates would have been quantitatively assessed in both laboratory and field tests to achieve the optimal destruction of contaminants of concern. WRI and Earth Tech identified a site contaminated with high concentrations of methanol associated with petroleum hydrocarbons. The site was assessed and a remediation project plan was prepared; however, the site was soon acquired by a new company. An agreement between Earth Tech, WRI, and the new site owners could not be reached; therefore, a work was performed to identify a new project site. Task 33 was terminated and the available funding was redeployed to other Tasks after receiving approval from the U.S. DOE task manager.

  8. ORNL/MMES research into remedial applications of zero-valence metals. 2. Bimetallic enhancements

    SciTech Connect

    Korte, N.; Muftikian, R.; Grittini, C.

    1995-12-01

    Recent reports have described the dehalogenation of many low molecular weight chlorinated hydrocarbons with zero-valence iron. Batch, column, and preliminary field studies have suggested that elemental iron could play a significant role in the remediation of contaminated groundwater. However, available data suggested that the technique may be unsuitable for high concentrations of the dichloroethenes and vinly chloride. Moreover, little of no reaction was observed with dichloromethane. Consequently, several bimetallic systems have been evaluated as a means of increasing the rate of reaction in order to extend zero-valence metal reduction to a greater variety of systems containing chlorinated hydrocarbons. Laboratory studies demonstrated that the rate of dehalogenation of trichloroethene can be increased by two orders of magnitude with a co-metal. In addition, zero-valence metal reduction can be extended to dechlorination of less reactive compounds such as dichloromethane.

  9. Surfactant-enhanced aquifer remediation at the Portsmouth Gaseous Diffusion Plant

    SciTech Connect

    Jackson, R.E.; Londergan, J.T.; Pickens, J.F.

    1995-10-01

    Many DOE facilities are situated in areas of sand and gravel which have become polluted with dense, non-aqueous phase liquids or DNAPLs, such as chlorinated solvents, from the various industrial operations at these facilities. The presence of such DNAPLs in sand and gravel aquifers is now recognized as the principal factor in the failure of standard ground-water remediation methods. The principal objective of this study, as stated in the Statement of Work of the contract (DE-AC21-92MC29111), is to demonstrate that multi-component DNAPLs can be readily solubilized in sand and gravel aquifers by dilute surfactant solutions. The specific objectives of the contract are: to identify dilute surfactants or blends of surfactants in the laboratory that will efficiently extract multi-component DNAPLs from sand and gravel aquifers by micellar solubilization (Phase 1); 2. to test the efficacy of the identified surfactants or blends of surfactants to solubilize in situ perchloroethylene (PCE) and trichloroethylene (TCE) DNAPLs by the injection and the subsequent extraction through an existing well or wells at a government-owned contaminated site (Phase 1); and 3. to demonstrate the full-scale operation of this remedial technology at a government-owned contaminated site (Phase 2). Specific objective number 1 has been completed and reported to DOE. However, the results of the test referred to in specific objective number 2, conducted at Paducah Gaseous Diffusion Plant in 1994, were inconclusive. Following this first test, it was decided by DOE and INTERA to move the test site elsewhere due to difficulties with obtaining core samples of the sand and gravel aquifer containing the DNAPL and with ascertaining the location of the DNAPL relative to the injection well. The solubilization test at the Portsmouth Gaseous Diffusion Plant (PORTS) will constitute the second test of Phase 1 of this contract.

  10. Enhanced-electrokinetic remediation of copper-pyrene co-contaminated soil with different oxidants and pH control.

    PubMed

    Cang, Long; Fan, Guang-Ping; Zhou, Dong-Mei; Wang, Quan-Ying

    2013-02-01

    Electrokinetic (EK) remediation has potential to simultaneously remove heavy metals and organic compounds from soil, but the removal percent of these pollutants is very low in general if no enhancing treatment is applied. This study developed a new enhanced-EK remediation technology to decontaminate a heavy metal-organic compound co-contaminated soil by applying different oxidants and pH control. A red soil was used as a model clayed soil, and was spiked with pyrene and Cu at about 500 mg kg(-1) for both to simulate real situation. Bench-scale EK experiments were performed using four oxidants (H(2)O(2), NaClO, KMnO(4), and Na(2)S(2)O(8)) and controlling electrolyte pH at 3.5 or 10. After the treatments with 1.0 V cm(-1) of voltage gradient for 335 h, soil pH, electrical conductivity, and the concentrations and chemical fractionations of soil pyrene and Cu were analyzed. The results showed that there was significant migration of pyrene and Cu from the soil, and the removal percent of soil pyrene and Cu varied in the range of 30-52% and 8-94%, respectively. Low pH favoured the migration of soil Cu, while KMnO(4) was the best one for the degradation of pyrene among the tested oxidants, although it unfortunately prevented the migration of soil Cu by forming Cu oxide. Application of Na(2)S(2)O(8) and to control the catholyte pH at 3.5 were found to be the best operation conditions for decontaminating the Cu-pyrene co-contaminated soil. PMID:23177009

  11. Application of iron electrode corrosion enhanced electrokinetic-Fenton oxidation to remediate diesel contaminated soils: A laboratory feasibility study

    NASA Astrophysics Data System (ADS)

    Tsai, Tzai-Tang; Sah, Jygau; Kao, Chih-Ming

    2010-01-01

    SummaryDiesel soil contamination on gas stations or refinery plants is a worldwide environmental problem. The main objectives of this study were to (1) evaluate the efficiency of electrokinetic (EK) by using different electrode materials (graphite and iron rods) and electrolytes (tap water, 0.01 M NaCl, and 0.1 M NaCl) on the remediation of diesel contaminated soils, and (2) evaluate the feasibility of total petroleum hydrocarbon-diesel (TPH-D) reducing in soils via EK-Fenton oxidation enhanced by corroded iron electrode. The EK and EK-Fenton experiments were conducted in batch and sand box experiments, respectively. Batch experiments reveal that the most appropriate electrolyte was 0.1 M NaCl when iron electrode was used in the EK system. Sand box experiments indicate that the TPH-D concentration dropped from 10,000 to 300 mg kg -1 when amorphous iron/total iron (Fe o/Fe t) ratio increased from 0.1 to 0.33, with the addition of 8% of H 2O 2 and 0.1 M NaCl after 60 days of EK-Fenton operation. Electrokinetically enhanced oxidation with the presence of both H 2O 2 and Fe 3O 4 (iron electrode corrosion) resulted in higher TPH-D removal efficiency (97%) compared to the efficiencies observed from EK (55%) or Fenton oxidation (27%) alone. This demonstrates that EK-Fenton oxidation catalyzed by iron electrode corrosion is a valuable direction to efficiently and effectively remediate diesel contaminated soils.

  12. Resource waves: phenological diversity enhances foraging opportunities for mobile consumers

    USGS Publications Warehouse

    Armstrong, Jonathan B.; Takimoto, Gaku; Schindler, Daniel E.; Hayes, Matthew M.; Kauffman, Matthew J.

    2016-01-01

    Time can be a limiting constraint for consumers, particularly when resource phenology mediates foraging opportunity. Though a large body of research has explored how resource phenology influences trophic interactions, this work has focused on the topics of trophic mismatch or predator swamping, which typically occur over short periods, at small spatial extents or coarse resolutions. In contrast many consumers integrate across landscape heterogeneity in resource phenology, moving to track ephemeral food sources that propagate across space as resource waves. Here we provide a conceptual framework to advance the study of phenological diversity and resource waves. We define resource waves, review evidence of their importance in recent case studies, and demonstrate their broader ecological significance with a simulation model. We found that consumers ranging from fig wasps (Chalcidoidea) to grizzly bears (Ursus arctos) exploit resource waves, integrating across phenological diversity to make resource aggregates available for much longer than their component parts. In model simulations, phenological diversity was often more important to consumer energy gain than resource abundance per se. Current ecosystem-based management assumes that species abundance mediates the strength of trophic interactions. Our results challenge this assumption and highlight new opportunities for conservation and management. Resource waves are an emergent property of consumer–resource interactions and are broadly significant in ecology and conservation.

  13. Resource waves: phenological diversity enhances foraging opportunities for mobile consumers.

    PubMed

    Armstrong, Jonathan B; Takimoto, Gaku; Schindler, Daniel E; Hayes, Matthew M; Kauffman, Matthew J

    2016-05-01

    Time can be a limiting constraint for consumers, particularly when resource phenology mediates foraging opportunity. Though a large body of research has explored how resource phenology influences trophic interactions, this work has focused on the topics of trophic mismatch or predator swamping, which typically occur over short periods, at small spatial extents or coarse resolutions. In contrast many consumers integrate across landscape heterogeneity in resource phenology, moving to track ephemeral food sources that propagate across space as resource waves. Here we provide a conceptual framework to advance the study of phenological diversity and resource waves. We define resource waves, review evidence of their importance in recent case studies, and demonstrate their broader ecological significance with a simulation model. We found that consumers ranging from fig wasps (Chalcidoidea) to grizzly bears (Ursus arctos) exploit resource waves, integrating across phenological diversity to make resource aggregates available for much longer than their component parts. In model simulations, phenological diversity was often more important to consumer energy gain than resource abundance per se. Current ecosystem-based management assumes that species abundance mediates the strength of trophic interactions. Our results challenge this assumption and highlight new opportunities for conservation and management. Resource waves are an emergent property of consumer-resource interactions and are broadly significant in ecology and conservation. PMID:27349088

  14. Humic acid enhanced remediation of an emplaced diesel source in groundwater. 1. Laboratory-based pilot scale test.

    PubMed

    Van Stempvoort, D R; Lesage, S; Novakowski, K S; Millar, K; Brown, S; Lawrence, J R

    2002-02-01

    The enhanced solubility of petroleum-derived compounds in humic acid solutions is the basis for a new groundwater remediation technology. In this unique pilot-scale test, a stationary contaminant source consisting of diesel fuel was placed below the water table in a model sand aquifer (1.2 x 5.5 x 1.8-m deep) and flushed with water at a flow rate of 2 cm/h over 5 years. At 51 days, laboratory grade humic acid was added to the water and maintained at a level of approximately 0.8 g/l. The addition of humic acid had only a small impact on the aqueous transport of the BTEX components, which were rapidly dissolved from the diesel, but had a large effect on the flushing of PAHs, including methylated naphthalenes (MNs). Binding to aqueous humic acid enhanced the solubilization of MNs two- to tenfold. During aqueous transport, biodegradation of the BTEX and PAHs occurred, limiting the lateral and longitudinal extent of the diesel contaminant plume in the model aquifer. It appears that through enhanced solubilization, the overall biodegradation rate of the MNs was increased. As the various MNs were depleted from the diesel source, the MN plume shrank and then disappeared.

  15. Genetic diversity enhances the resistance of a seagrass ecosystem to disturbance

    PubMed Central

    Hughes, A. Randall; Stachowicz, John J.

    2004-01-01

    Motivated by recent global reductions in biodiversity, empirical and theoretical research suggests that more species-rich systems exhibit enhanced productivity, nutrient cycling, or resistance to disturbance or invasion relative to systems with fewer species. In contrast, few data are available to assess the potential ecosystem-level importance of genetic diversity within species known to play a major functional role. Using a manipulative field experiment, we show that increasing genotypic diversity in a habitat-forming species (the seagrass Zostera marina) enhances community resistance to disturbance by grazing geese. The time required for recovery to near predisturbance densities also decreases with increasing eelgrass genotypic diversity. However, there is no effect of diversity on resilience, measured as the rate of shoot recovery after the disturbance, suggesting that more rapid recovery in diverse plots is due solely to differences in disturbance resistance. Genotypic diversity did not affect ecosystem processes in the absence of disturbance. Thus, our results suggest that genetic diversity, like species diversity, may be most important for enhancing the consistency and reliability of ecosystems by providing biological insurance against environmental change. PMID:15184681

  16. PILOT-SCALE EVALUATION OF THE IRON-ENHANCED DECHLORINATION TECHNOLOGY FOR REMEDIATION OF CONTAMINATED GROUNDWATER

    EPA Science Inventory

    An iron-enhanced dechlorination technology was evaluated, under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) program, at a contaminated printed circuit board manufacturing site in New Jersey. This paper describes the feasibility...

  17. DEMONSTRATION OF PILOT-SCALE PREVAPORATION SYSTEMS FOR VOLATILE ORGANIC COMPOUND REMOVAL FROM A SURFACTANT ENHANCED AQUIFER REMEDIATION FLUID. I. SPIRAL WOUND MEMBRANE MODULES

    EPA Science Inventory

    During the summer of 1996, a pilot-scale demonstration of a surfactant enhanced aquifer remediation (SEAR) process for removal of dense non-aqueous phase liquids (DNAPLs) from soils was conducted at Hill Air Force Base in Layton, Utah. Five thousand gallons of the extracted DNAP...

  18. Bird functional diversity decreases with time since disturbance: Does patchy prescribed fire enhance ecosystem function?.

    PubMed

    Sitters, Holly; Di Stefano, Julian; Christie, Fiona; Swan, Matthew; York, Alan

    2016-01-01

    Animal species diversity is often associated with time since disturbance, but the effects of disturbances such as fire on functional diversity are unknown. Functional diversity measures the range, abundance, and distribution of trait values in a community, and links changes in species composition with the consequences for ecosystem function. Improved understanding of the relationship between time since fire (TSF) and functional diversity is critical given that the frequency of both prescribed fire and wildfire is expected to increase. To address this knowledge gap, we examined responses of avian functional diversity to TSF and two direct measures of environmental heterogeneity, plant diversity, and structural heterogeneity. We surveyed birds across a 70-year chronosequence spanning four vegetation types in southeast Australia. Six bird functional traits were used to derive four functional diversity indices (richness, evenness, divergence, and dispersion) and the effects of TSF, plant diversity and structural heterogeneity on species richness and the functional diversity indices were examined using mixed models. We used a regression tree method to identify traits associated with species more common in young vegetation. Functional richness and dispersion were negatively associated with TSF in all vegetation types, suggesting that recent prescribed fire generates heterogeneous vegetation and provides greater opportunities for resource partitioning. Species richness was not significantly associated with TSF, and is probably an unreliable surrogate for functional diversity in fire-prone systems. A positive, relationship between functional evenness and structural heterogeneity was comnon to all vegetation types, suggesting that fine-scale (tens of meters) structural variation can enhance ecosystem function. Species more common in young vegetation were primarily linked by their specialist diets, indicating that ecosystem services such as seed dispersal and insect control

  19. Bird functional diversity decreases with time since disturbance: Does patchy prescribed fire enhance ecosystem function?.

    PubMed

    Sitters, Holly; Di Stefano, Julian; Christie, Fiona; Swan, Matthew; York, Alan

    2016-01-01

    Animal species diversity is often associated with time since disturbance, but the effects of disturbances such as fire on functional diversity are unknown. Functional diversity measures the range, abundance, and distribution of trait values in a community, and links changes in species composition with the consequences for ecosystem function. Improved understanding of the relationship between time since fire (TSF) and functional diversity is critical given that the frequency of both prescribed fire and wildfire is expected to increase. To address this knowledge gap, we examined responses of avian functional diversity to TSF and two direct measures of environmental heterogeneity, plant diversity, and structural heterogeneity. We surveyed birds across a 70-year chronosequence spanning four vegetation types in southeast Australia. Six bird functional traits were used to derive four functional diversity indices (richness, evenness, divergence, and dispersion) and the effects of TSF, plant diversity and structural heterogeneity on species richness and the functional diversity indices were examined using mixed models. We used a regression tree method to identify traits associated with species more common in young vegetation. Functional richness and dispersion were negatively associated with TSF in all vegetation types, suggesting that recent prescribed fire generates heterogeneous vegetation and provides greater opportunities for resource partitioning. Species richness was not significantly associated with TSF, and is probably an unreliable surrogate for functional diversity in fire-prone systems. A positive, relationship between functional evenness and structural heterogeneity was comnon to all vegetation types, suggesting that fine-scale (tens of meters) structural variation can enhance ecosystem function. Species more common in young vegetation were primarily linked by their specialist diets, indicating that ecosystem services such as seed dispersal and insect control

  20. MOVING BEYOND PUMP AND TREAT TOWARD ENHANCED ATTENUATION AND COMBINED REMEDIES T-AREA, SAVANNAH RIVER SITE

    SciTech Connect

    Looney, B; Brian Riha, B; Warren Hyde, W; Jay Noonkester, J; Gerald Blount, G

    2008-04-03

    Groundwater beneath T-Area, a former laboratory and semiworks operation at the Department of Energy (DOE) Savannah River Site, is contaminated by chlorinated solvents (cVOCs). Since the contamination was detected in the 1980s, the cVOCs at T-Area have been treated by a combination of soil vapor extraction and groundwater pump and treat. The site has received approval to discontinue the active treatments and implement a full scale test of enhanced attenuation--an engineering and regulatory strategy that has recently been developed by DOE and the Interstate Technology and Regulatory Council. Enhanced attenuation uses active engineering solutions to alter the target site in such a way that the contaminant plume will passively stabilize and shrink and to document that the action will be effective, timely, and sustainable. The paradigm recognizes that attenuation remedies are fundamentally based on a mass balance. Thus, long-term plume dynamics can be altered either by reducing the contaminant loading from the source or by increasing the rate of natural attenuation processes within all, or part of, the plume volume. The combination of technologies that emerged for T-Area included: (1) neat (pure) vegetable oil deployment in the deep vadose zone in the former source area, (2) emulsified vegetable oil deployment within the footprint of the groundwater plume, and (3) identification of attenuation mechanisms and rates for the distal portion of the plume. In the first part, neat oil spreads laterally forming a thin layer on the water table to intercept and reduce future cVOC loading (via partitioning) and reduce oxygen inputs (via biostimulation). In the second and third parts, emulsified oil forms active bioremediation reactor zones within the plume footprint to degrade existing groundwater contamination (via reductive dechlorination) and stimulates long-term attenuation capacity in the distal plume (via cometabolism). For T-Area, the enhanced attenuation development

  1. Conductivity reduction due to emulsification during surfactant enhanced-aquifer remediation. 2. Formation of emulsion in situ.

    PubMed

    Jain, Vivek; Demond, Avery H

    2002-12-15

    Permeability reduction due to surfactant emulsification can impact the effectiveness of surfactant-enhanced aquifer remediation (SEAR). The objective of this study was to examine the process of in situ emulsification in systems composed of tetrachloroethylene (PCE) and solutions of two nonionic surfactants selected for their ability to enhance solubility. The injection of the surfactant solutions into columns packed with sand-sized silica particles containing residual saturations of PCE resulted in the formation of an emulsion with an average droplet diameter of 0.1-0.2 microm, about an order of magnitude smaller than that of the ex situ formed emulsion. The measurements of hydraulic conductivity showed an initial decrease, followed by a gradual increase, with a final steady-state reduction of about 35% after the injection of 7-8 pore volumes of surfactant solution, of which about 8% could be attributed to the deposition of the emulsion. To describe the observed trends, the modified emulsion transport model from Part 1 was modified to include the processes of the formation of the emulsion and the reduction of the PCE residual. The good comparison between the simulations and the experimental data suggests that the model correctly reflects the multiple processes controlling the hydraulic conductivity of the packed columns during surfactant solution injection.

  2. Humic acid enhanced remediation of an emplaced diesel source in groundwater. 2. Numerical model development and application.

    PubMed

    Molson, J W; Frind, E O; Van Stempvoort, D R; Lesage, S

    2002-02-01

    A pilot scale experiment for humic acid-enhanced remediation of diesel fuel, described in Part 1 of this series, is numerically simulated in three dimensions. Groundwater flow, enhanced solubilization of the diesel source, and reactive transport of the dissolved contaminants and humic acid carrier are solved with a finite element Galerkin approach. The model (BIONAPL) is calibrated by comparing observed and simulated concentrations of seven diesel fuel components (BTEX and methyl-, dimethyl- and trimethylnaphthalene) over a 1500-day monitoring period. Data from supporting bench scale tests were used to estimate contaminant-carrier binding coefficients and to simulate two-site sorption of the carrier to the aquifer sand. The model accurately reproduced the humic acid-induced 10-fold increase in apparent solubility of trimethylnaphthalene. Solubility increases on the order of 2-5 were simulated for methylnaphthalene and dimethylnaphthalene, respectively. Under the experimental and simulated conditions, the residual 500-ml diesel source was almost completely dissolved and degraded within 5 years. Without humic acid flushing, the simulations show complete source dissolution would take about six times longer.

  3. Parallel Exploitation of Diverse Host Nutrients Enhances Salmonella Virulence

    PubMed Central

    Steeb, Benjamin; Claudi, Beatrice; Burton, Neil A.; Tienz, Petra; Schmidt, Alexander; Farhan, Hesso; Mazé, Alain; Bumann, Dirk

    2013-01-01

    Pathogen access to host nutrients in infected tissues is fundamental for pathogen growth and virulence, disease progression, and infection control. However, our understanding of this crucial process is still rather limited because of experimental and conceptual challenges. Here, we used proteomics, microbial genetics, competitive infections, and computational approaches to obtain a comprehensive overview of Salmonella nutrition and growth in a mouse typhoid fever model. The data revealed that Salmonella accessed an unexpectedly diverse set of at least 31 different host nutrients in infected tissues but the individual nutrients were available in only scarce amounts. Salmonella adapted to this situation by expressing versatile catabolic pathways to simultaneously exploit multiple host nutrients. A genome-scale computational model of Salmonella in vivo metabolism based on these data was fully consistent with independent large-scale experimental data on Salmonella enzyme quantities, and correctly predicted 92% of 738 reported experimental mutant virulence phenotypes, suggesting that our analysis provided a comprehensive overview of host nutrient supply, Salmonella metabolism, and Salmonella growth during infection. Comparison of metabolic networks of other pathogens suggested that complex host/pathogen nutritional interfaces are a common feature underlying many infectious diseases. PMID:23633950

  4. Correlation between DNAPL distribution area and dissolved concentration in surfactant enhanced aquifer remediation effluent: A two-dimensional flow cell study.

    PubMed

    Wu, Bin; Li, Huiying; Du, Xiaoming; Zhong, Lirong; Yang, Bin; Du, Ping; Gu, Qingbao; Li, Fasheng

    2016-02-01

    During the process of surfactant enhanced aquifer remediation (SEAR), free phase dense non-aqueous phase liquid (DNAPL) may be mobilized and spread. The understanding of the impact of DNAPL spreading on the SEAR remediation is not sufficient with its positive effect infrequently mentioned. To evaluate the correlation between DNAPL spreading and remediation efficiency, a two-dimensional sandbox apparatus was used to simulate the migration and dissolution process of 1,2-DCA (1,2-dichloroethane) DNAPL in SEAR. Distribution area of DNAPL in the sandbox was determined by digital image analysis and correlated with effluent DNAPL concentration. The results showed that the effluent DNAPL concentration has significant positive linear correlation with the DNAPL distribution area, indicating the mobilization of DNAPL could improve remediation efficiency by enlarging total NAPL-water interfacial area for mass transfer. Meanwhile, the vertical migration of 1,2-DCA was limited within the boundary of aquifer in all experiments, implying that by manipulating injection parameters in SEAR, optimal remediation efficiency can be reached while the risk of DNAPL vertical migration is minimized. This study provides a convenient visible and quantitative method for the optimization of parameters for SEAR project, and an approach of rapid predicting the extent of DNAPL contaminant distribution based on the dissolved DNAPL concentration in the extraction well.

  5. Cultivating Diversity and Competency in STEM: Challenges and Remedies for Removing Virtual Barriers to Constructing Diverse Higher Education Communities of Success

    PubMed Central

    Whittaker, Joseph A.; Montgomery, Beronda L.

    2012-01-01

    The need to increase the number of college graduates in Science, Technology, Engineering, and Mathematics (STEM) disciplines is a national issue. As the demographics of the United States’ population grow increasingly more diverse, the recognition that students of color are disproportionately under-represented among those individuals successful at completing STEM degrees requires exigent and sustained intervention. Although a range of efforts and funding have been committed to increasing the success of under-represented minority (URM) students at primarily white, or majority, institutions, widespread progress has been slow. Simultaneously, Historically Black Colleges and Universities and Minority Serving Institutions have demonstrated disproportionate successes in graduating URM students with STEM degrees and those that proceed to completing graduate-level degrees in the sciences. The differential successes of particular institutions with promoting the achievement of diverse individuals in obtaining academic STEM degrees suggest that with committed and strategic leadership, advancements in creating academic communities that promote the success of a diverse range of students in STEM can be achieved in part through assessing and mitigating environmental barriers that impede success at majority institutions. In this paper, we address issues related to the engagement of URM students in majority settings and describe some efforts that have shown success for promoting diversity in STEM and highlight continuing issues and factors associated with cultivating diversity in academic STEM disciplines at majority institutions. Recommended efforts include addressing academic assistance, professional and cultural socialization issues and institutional environmental factors that are associated with success or lack thereof for URMs in STEM. PMID:23493445

  6. Diversity climate enhances work outcomes through trust and openness in workgroup communication.

    PubMed

    Hofhuis, Joep; van der Rijt, Pernill G A; Vlug, Martijn

    2016-01-01

    Diversity climate, defined as an organizational climate characterized by openness towards and appreciation of individual differences, has been shown to enhance outcomes in culturally diverse teams. To date, it remains unclear which processes are responsible for these findings. This paper presents two quantitative studies (n = 91; 246) that identify trust and openness in workgroup communication as possible mediators. We replicate earlier findings that perceived diversity climate positively relates to job satisfaction, sense of inclusion, work group identification and knowledge sharing in teams. In study 1, trust is shown to mediate the effects of perceived diversity climate on team members' sense of inclusion. In study 2, trust mediates the relationship between perceived diversity climate and workgroup identification and openness mediates its relationship with knowledge sharing. PMID:27375983

  7. Diversity climate enhances work outcomes through trust and openness in workgroup communication.

    PubMed

    Hofhuis, Joep; van der Rijt, Pernill G A; Vlug, Martijn

    2016-01-01

    Diversity climate, defined as an organizational climate characterized by openness towards and appreciation of individual differences, has been shown to enhance outcomes in culturally diverse teams. To date, it remains unclear which processes are responsible for these findings. This paper presents two quantitative studies (n = 91; 246) that identify trust and openness in workgroup communication as possible mediators. We replicate earlier findings that perceived diversity climate positively relates to job satisfaction, sense of inclusion, work group identification and knowledge sharing in teams. In study 1, trust is shown to mediate the effects of perceived diversity climate on team members' sense of inclusion. In study 2, trust mediates the relationship between perceived diversity climate and workgroup identification and openness mediates its relationship with knowledge sharing.

  8. Remediation of TCE-contaminated groundwater using acid/BOF slag enhanced chemical oxidation.

    PubMed

    Tsai, T T; Kao, C M; Wang, J Y

    2011-04-01

    The objective of this study was to evaluate the potential of applying acid/H(2)O(2)/basic oxygen furnace slag (BOF slag) and acid/S(2)O(8)(2-)/BOF slag systems to enhance the chemical oxidation of trichloroethylene (TCE)-contaminated groundwater. Results from the bench-scale study indicate that TCE oxidation via the Fenton-like oxidation process can be enhanced with the addition of BOF slag at low pH (pH=2-5.2) and neutral (pH=7.1) conditions. Because the BOF slag has iron abundant properties (14% of FeO and 6% of Fe(2)O(3)), it can be sustainably reused for the supplement of iron minerals during the Fenton-like or persulfate oxidation processes. Results indicate that higher TCE removal efficiency (84%) was obtained with the addition of inorganic acid for the activation of Fenton-like reaction compared with the experiments with organic acids addition (with efficiency of 10-15% lower) (BOF slag=10gL(-1); initial pH=5.2). This could be due to the fact that organic acids would compete with TCE for available oxidants. Results also indicate that the pH value had a linear correlation with the observed first-order decay constant of TCE, and thus, lower pH caused a higher TCE oxidation rate.

  9. Biodegradation of aged diesel in diverse soil matrixes: impact of environmental conditions and bioavailability on microbial remediation capacity.

    PubMed

    Sutton, Nora B; van Gaans, Pauline; Langenhoff, Alette A M; Maphosa, Farai; Smidt, Hauke; Grotenhuis, Tim; Rijnaarts, Huub H M

    2013-07-01

    While bioremediation of total petroleum hydrocarbons (TPH) is in general a robust technique, heterogeneity in terms of contaminant and environmental characteristics can impact the extent of biodegradation. The current study investigates the implications of different soil matrix types (anthropogenic fill layer, peat, clay, and sand) and bioavailability on bioremediation of an aged diesel contamination from a heterogeneous site. In addition to an uncontaminated sample for each soil type, samples representing two levels of contamination (high and low) were also used; initial TPH concentrations varied between 1.6 and 26.6 g TPH/kg and bioavailability between 36 and 100 %. While significant biodegradation occurred during 100 days of incubation under biostimulating conditions (64.4-100 % remediation efficiency), low bioavailability restricted full biodegradation, yielding a residual TPH concentration. Respiration levels, as well as the abundance of alkB, encoding mono-oxygenases pivotal for hydrocarbon metabolism, were positively correlated with TPH degradation, demonstrating their usefulness as a proxy for hydrocarbon biodegradation. However, absolute respiration and alkB presence were dependent on soil matrix type, indicating the sensitivity of results to initial environmental conditions. Through investigating biodegradation potential across a heterogeneous site, this research illuminates the interplay between soil matrix type, bioavailability, and bioremediation and the implications of these parameters for the effectiveness of an in situ treatment.

  10. Effects of source zone heterogeneity on surfactant-enhanced NAPL dissolution and resulting remediation end-points.

    PubMed

    Saenton, S; Illangasekare, T H; Soga, K; Saba, T A

    2002-11-01

    The effectiveness of removal of nonaqueous phase liquids (NAPLs) from the entrapment source zone of the subsurface has been limited by soil heterogeneity and the inability to locate all entrapped sources. The goal of this study was to demonstrate the uncertainty of degree of source removal associated with aquifer heterogeneity. In this demonstration, source zone NAPL removal using surfactant-enhanced dissolution was considered. Model components that simulate the processes of natural dissolution in aqueous phase and surfactant-enhanced dissolution were incorporated into an existing code of contaminant transport. The dissolution modules of the simulator used previously developed Gilland-Sherwood type phenomenological models of NAPL dissolution to estimate mass transfer coefficients that are upscaleable to multidimensional flow conditions found at field sites. The model was used to simulate the mass removal from 10 NAPL entrapment zone configurations based on previously conducted two-dimensional tank experiments. These entrapment zones represent the NAPL distribution in spatially correlated random fields of aquifer hydraulic conductivity. The numerical simulations representing two-dimensional conditions show that effectiveness of mass removal depends on the aquifer heterogeneity that controls the NAPL entrapment and delivery of the surfactant to the locations of entrapped NAPLs. Flow bypassing resulting from heterogeneity and the reduction of relative permeability due to NAPL entrapment reduces the delivery efficiency of the surfactant, thus prolonging the remediation time to achieve desired end-point NAPL saturations and downstream dissolved concentrations. In some extreme cases, the injected surfactant completely bypassed the NAPL source zones. It was also found that mass depletion rates for different NAPL source configurations vary significantly. The study shows that heterogeneity result in uncertainties in the mass removal and achievable end-points that are

  11. Remediation of hexachlorobenzene contaminated soils by rhamnolipid enhanced soil washing coupled with activated carbon selective adsorption.

    PubMed

    Wan, Jinzhong; Chai, Lina; Lu, Xiaohua; Lin, Yusuo; Zhang, Shengtian

    2011-05-15

    The present study investigates the selective adsorption of hexachlorobenzene (HCB) from rhamnolipid solution by a powdered activated carbon (PAC). A combined soil washing-PAC adsorption technique is further evaluated on the removal of HCB from two soils, a spiked kaolin and a contaminated real soil. PAC at a dosage of 10 g L(-1) could achieve a HCB removal of 80-99% with initial HCB and rhamnolipid concentrations of 1 mg L(-1) and 3.3-25 g L(-1), respectively. The corresponding adsorptive loss of rhamnolipid was 8-19%. Successive soil washing-PAC adsorption tests (new soil sample was subjected to washing for each cycle) showed encouraging leaching and adsorption performances for HCB. When 25 g L(-1) rhamnolipid solution was applied, HCB leaching from soils was 55-71% for three cycles of washing, and HCB removal by PAC was nearly 90%. An overall 86% and 88% removal of HCB were obtained for kaolin and real soil, respectively, by using the combined process to wash one soil sample for twice. Our investigation suggests that coupling AC adsorption with biosurfactant-enhanced soil washing is a promising alternative to remove hydrophobic organic compounds from soils. PMID:21397398

  12. Effect of OSE(II)-Enhanced Soil Washing(OESW) for TPH -Contaminated Soil Remediation

    NASA Astrophysics Data System (ADS)

    Hwang, J. H.; Lee, D. H.; Woo, N. C.

    2015-12-01

    The objectives of this study were to perform potentially suitable active agent that solubilize total petroleum hydrocarbon (TPH) present as contaminants and to evaluate the optimal range of process parameters that can increase the removal efficiency in OSE(II)-enhanced soil washing (OESW) pilot tests. Used experimental method for solubilisation of TPH by using OSE(II) was batch experiments. The active agent solution parameters for OESW pilot tests were solution concentration, solution pH in the OESW pilot tests. Based on the batch experiments, OSE(II) was proved as a suitable active agent that solubilizes TPH present as contaminants. The highest recovery (92-95 %) of the contaminants was obtained using a OSE(II) in the batch experiments. The pilot test results revealed that the optimum conditions were achieved with a OSE(II) surfactant solution concentration of 10 % (v/v), a OSE(II) surfactant solution pH of 6.5-7.5 of OSE(II) active agent solution. The maximum removal of contaminants (88 %) was obtained when optimum conditions were simultaneously met in pilot-scale OESW operations. These results confirm the viability of OESW for treating TPH-contaminated soil.

  13. Can Academic Reference Librarians Enhance the Cultural Diversity of the Nation's Colleges and Universities?

    ERIC Educational Resources Information Center

    Wilkinson, David

    Academic reference librarians can enhance the campus cultural diversity of colleges and universities by displaying sensitivity at the reference desk; understanding multicultural group behaviors; avoiding stereotyped attitudes; appreciating a wide range of cognitive style differences; striving to make multicultural students feel comfortable;…

  14. Assessing the Crossdisciplinarity of Technology-Enhanced Learning with Science Overlay Maps and Diversity Measures

    ERIC Educational Resources Information Center

    Kalz, Marco; Specht, Marcus

    2014-01-01

    This paper deals with the assessment of the crossdisciplinarity of technology-enhanced learning (TEL). Based on a general discussion of the concept interdisciplinarity and a summary of the discussion in the field, two empirical methods from scientometrics are introduced and applied. Science overlay maps and the Rao-Stirling diversity index are…

  15. Enhanced carcinogenicity by coexposure to arsenic and iron and a novel remediation system for the elements in well drinking water.

    PubMed

    Kumasaka, Mayuko Y; Yamanoshita, Osamu; Shimizu, Shingo; Ohnuma, Shoko; Furuta, Akio; Yajima, Ichiro; Nizam, Saika; Khalequzzaman, Md; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

    2013-03-01

    Various carcinomas including skin cancer are explosively increasing in arsenicosis patients who drink arsenic-polluted well water, especially in Bangladesh. Although well drinking water in the cancer-prone areas contains various elements, very little is known about the effects of elements except arsenic on carcinogenicity. In order to clarify the carcinogenic effects of coexposure to arsenic and iron, anchorage-independent growth and invasion in human untransformed HaCaT and transformed A431 keratinocytes were examined. Since the mean ratio of arsenic and iron in well water was 1:10 in cancer-prone areas of Bangladesh, effects of 1 μM arsenic and 10 μM iron were investigated. Iron synergistically promoted arsenic-mediated anchorage-independent growth in untransformed and transformed keratinocytes. Iron additionally increased invasion in both types of keratinocytes. Activities of c-SRC and ERK that regulate anchorage-independent growth and invasion were synergistically enhanced in both types of keratinocytes. Our results suggest that iron promotes arsenic-mediated transformation of untransformed keratinocytes and progression of transformed keratinocytes. We then developed a low-cost and high-performance adsorbent composed of a hydrotalcite-like compound for arsenic and iron. The adsorbent rapidly reduced concentrations of both elements from well drinking water in cancer-prone areas of Bangladesh to levels less than those in WHO health-based guidelines for drinking water. Thus, we not only demonstrated for the first time increased carcinogenicity by coexposure to arsenic and iron but also proposed a novel remediation system for well drinking water.

  16. Initial genetic diversity enhances population establishment and alters genetic structuring of a newly established Daphnia metapopulation.

    PubMed

    Holmes, Christopher J; Pantel, Jelena H; Schulz, Kimberly L; Cáceres, Carla E

    2016-07-01

    When newly created habitats are initially colonized by genotypes with rapid population growth rates, later arriving colonists may be prevented from establishing. Although these priority effects have been documented in multiple systems, their duration may be influenced by the diversity of the founding population. We conducted a large-scale field manipulation to investigate how initial clonal diversity influences temporal and landscape patterns of genetic structure in a developing metapopulation. Six genotypes of obligately asexual Daphnia pulex were stocked alone (no clonal diversity) or in combination ('high' clonal diversity) into newly created experimental woodland ponds. We also measured the population growth rate of all clones in the laboratory when raised on higher-quality and lower-quality resources. Our predictions were that in the 3 years following stocking, clonally diverse populations would be more likely to persist than nonclonally diverse populations and exhibit evidence for persistent founder effects. We expected that faster growing clones would be found in more pools and comprise a greater proportion of individuals genotyped from the landscape. Genetic composition, both locally and regionally, changed significantly following stocking. Six of 27 populations exhibited evidence for persistent founder effects, and populations stocked with 'high' clonal diversity were more likely to exhibit these effects than nonclonally diverse populations. Performance in the laboratory was not predictive of clonal persistence or overall dominance in the field. Hence, we conclude that although laboratory estimates of fitness did not fully explain metapopulation genetic structure, initial clonal diversity did enhance D. pulex population establishment and persistence in this system.

  17. Genetic diversity enhanced by ancient introgression and secondary contact in East Pacific black mangroves.

    PubMed

    Nettel, Alejandro; Dodd, Richard S; Afzal-Rafii, Zara; Tovilla-Hernández, Cristian

    2008-06-01

    Regional distribution of genetic diversity in widespread species may be influenced by hybridization with locally restricted, closely related species. Previous studies have shown that Central American East Pacific populations of the wide-ranged Avicennia germinans, the black mangrove, harbour higher genetic diversity than the rest of its range. Genetic diversity in this region might be enhanced by introgression with the locally restricted Avicennia bicolor. We tested the hypotheses of ancient hybridization using phylogenetic analysis of the internal transcribed spacer region (ITS) of the nuclear ribosomal DNA and intergenic chloroplast DNA; we also tested for current hybridization by population level analysis of nuclear microsatellites. Our results unveiled ancient ITS introgression between a northern Pacific Central American A. germinans lineage and A. bicolor. However, microsatellite data revealed contemporary isolation between the two species. Polymorphic ITS sequences from Costa Rica and Panama are consistent with a zone of admixture between the introgressant ITS A. germinans lineage and a southern Central American lineage of A. germinans. Interspecific introgression influenced lineage diversity and divergence at the nuclear ribosomal DNA; intraspecific population differentiation and secondary contact are more likely to have enhanced regional genetic diversity in Pacific Central American populations of the widespread A. germinans.

  18. The complicated substrates enhance the microbial diversity and zinc leaching efficiency in sphalerite bioleaching system.

    PubMed

    Xiao, Yunhua; Xu, YongDong; Dong, Weiling; Liang, Yili; Fan, Fenliang; Zhang, Xiaoxia; Zhang, Xian; Niu, Jiaojiao; Ma, Liyuan; She, Siyuan; He, Zhili; Liu, Xueduan; Yin, Huaqun

    2015-12-01

    This study used an artificial enrichment microbial consortium to examine the effects of different substrate conditions on microbial diversity, composition, and function (e.g., zinc leaching efficiency) through adding pyrite (SP group), chalcopyrite (SC group), or both (SPC group) in sphalerite bioleaching systems. 16S rRNA gene sequencing analysis showed that microbial community structures and compositions dramatically changed with additions of pyrite or chalcopyrite during the sphalerite bioleaching process. Shannon diversity index showed a significantly increase in the SP (1.460), SC (1.476), and SPC (1.341) groups compared with control (sphalerite group, 0.624) on day 30, meanwhile, zinc leaching efficiencies were enhanced by about 13.4, 2.9, and 13.2%, respectively. Also, additions of pyrite or chalcopyrite could increase electric potential (ORP) and the concentrations of Fe3+ and H+, which were the main factors shaping microbial community structures by Mantel test analysis. Linear regression analysis showed that ORP, Fe3+ concentration, and pH were significantly correlated to zinc leaching efficiency and microbial diversity. In addition, we found that leaching efficiency showed a positive and significant relationship with microbial diversity. In conclusion, our results showed that the complicated substrates could significantly enhance microbial diversity and activity of function.

  19. [Enhancement of GA3 and EDTA on Lolium perenne to remediate Pb contaminated soil and its detoxification mechanism].

    PubMed

    Wu, Qiu-Ling; Wang, Wen-Chu; He, Shan-Ying

    2014-10-01

    A pot experiment was conducted to study the effects of plant growth regulator GA3 and metal chelate EDTA on enhancing the remediation of Pb contaminated soil, and the detoxification mechanism of Lolium perenne grown on Pb contaminated soil at 250 and 500 mg · kg(-1). The results showed that cell wall deposition and vacuolar compartmentalization played important roles in the detoxification of Pb in L. perenne shoot. The addition of EDTA alone increased Pb concentration in plants and Pb proportions in soluble fraction and organelles fraction, and enhanced the toxicity of Pb to plant, leading to the significant reduction of the plant biomass (P < 0.05). Foliar spray of lower concentration of GA3 (1 μmol · L(-1) or 10 μmol · L(-1)) alone significantly increased Pb accumulation by L. perenne (P < 0.05), but Pb proportions in soluble and organelles fraction were decreased, which alleviated the adverse effects of Pb on plant, thus improving the growth of plants (P < 0.05), with 1 μmol · L(-1) GA3 being the most effective. In contract, the addition of 100 μmol · L(-1) GA3 decreased Pb concentration in L. perenne, but increased the proportions of Pb in soluble fraction and organelles fraction, resulting in the reduction of plant biomass. Lower concen- tration of GA3 might alleviate the adverse effects of Pb and/or EDTA on plant, since the biomass amounts in the different treatments were in order of GA3 alone of lower concentration > GA3 of lower concentration + EDTA > EDTA alone. The combination application of low concentration of GA3 and EDTA showed a synergistic effect on the Pb accumulation in L. perenne (P < 0.05). Especially, Pb concentration in shoot and Pb extraction efficiency reached 1250.6 mg · kg(-1) and 1.1%, respec- tively, under the treatment of EDTA + 1 μmol L(-1) GA3 on the Pb 500 mg · kg(-1) soil. Therefore, the application of 1 μmol · L(-1) GA3 along with EDTA appeared to be a potential approach for phytoremediation of Pb contaminated soil

  20. [Enhancement of GA3 and EDTA on Lolium perenne to remediate Pb contaminated soil and its detoxification mechanism].

    PubMed

    Wu, Qiu-Ling; Wang, Wen-Chu; He, Shan-Ying

    2014-10-01

    A pot experiment was conducted to study the effects of plant growth regulator GA3 and metal chelate EDTA on enhancing the remediation of Pb contaminated soil, and the detoxification mechanism of Lolium perenne grown on Pb contaminated soil at 250 and 500 mg · kg(-1). The results showed that cell wall deposition and vacuolar compartmentalization played important roles in the detoxification of Pb in L. perenne shoot. The addition of EDTA alone increased Pb concentration in plants and Pb proportions in soluble fraction and organelles fraction, and enhanced the toxicity of Pb to plant, leading to the significant reduction of the plant biomass (P < 0.05). Foliar spray of lower concentration of GA3 (1 μmol · L(-1) or 10 μmol · L(-1)) alone significantly increased Pb accumulation by L. perenne (P < 0.05), but Pb proportions in soluble and organelles fraction were decreased, which alleviated the adverse effects of Pb on plant, thus improving the growth of plants (P < 0.05), with 1 μmol · L(-1) GA3 being the most effective. In contract, the addition of 100 μmol · L(-1) GA3 decreased Pb concentration in L. perenne, but increased the proportions of Pb in soluble fraction and organelles fraction, resulting in the reduction of plant biomass. Lower concen- tration of GA3 might alleviate the adverse effects of Pb and/or EDTA on plant, since the biomass amounts in the different treatments were in order of GA3 alone of lower concentration > GA3 of lower concentration + EDTA > EDTA alone. The combination application of low concentration of GA3 and EDTA showed a synergistic effect on the Pb accumulation in L. perenne (P < 0.05). Especially, Pb concentration in shoot and Pb extraction efficiency reached 1250.6 mg · kg(-1) and 1.1%, respec- tively, under the treatment of EDTA + 1 μmol L(-1) GA3 on the Pb 500 mg · kg(-1) soil. Therefore, the application of 1 μmol · L(-1) GA3 along with EDTA appeared to be a potential approach for phytoremediation of Pb contaminated soil.

  1. THERMAL REMEDIATION

    EPA Science Inventory

    Thermal remediation is being proposed by Region I for remediation of the overburden soil and groundwater at the Solvent Recovery Services New England Superfund site. This presentation at the public meeting will acquaint area residents with thermal remediation. The two types of ...

  2. Enhanced Chemical Incident Response Plan (ECIRP). Appendix F, remediation analysis with Decision Support Tools (DSTs) for wide-area chemical hazards.

    SciTech Connect

    Hassig, Nancy L.; Pulsipher, Brent A.; Foltz, Greg W.; Hoette, Trisha Marie

    2011-07-01

    The Defense Threat Reduction Agency (DTRA) commissioned an assessment of the Consequence Management (CM) plans in place on military bases for response to a chemical attack. The effectiveness of the CM plans for recovering from chemical incidents was modeled using a multiple Decision Support Tools (DSTs). First, a scenario was developed based on an aerial dispersion of a chemical agent over a wide-area of land. The extent of contamination was modeled with the Hazard Prediction and Assessment Capability (HPAC) tool. Subsequently, the Analyzer for Wide Area Restoration Effectiveness (AWARE) tool was used to estimate the cost and time demands for remediation based on input of contamination maps, sampling and decontamination resources, strategies, rates and costs. The sampling strategies incorporated in the calculation were designed using the Visual Sample Plan (VSP) tool. Based on a gaps assessment and the DST remediation analysis, an Enhanced Chemical Incident Response Plan (ECIRP) was developed.

  3. DNAPL Surface Chemistry: Its Impact on DNAPL Distribution in the Vadose Zone and its Manipulation to Enhance Remediation

    SciTech Connect

    Suan Power; Stefan Grimberg; Miles Denham

    2003-06-16

    The remediation of DNAPLs in subsurface environments is often limited by the heterogeneous distribution of the organic fluid. The fraction of DNAPL that is in the high conductivity regions of the subsurface can often be recovered relatively easily, although DNAPL in lower conductivity regions is much more difficult to extract, either through direct pumping or remediation measures based on interface mass transfer. The distribution of DNAPL within the vadose zone is affected by a complex interplay of heterogeneities in the porous matrix and the interfacial properties defining the interactions among all fluid and solid phases. Decreasing the interfacial tension between a DNAPL and water in the vadose zone could change the spreading of the DNAPL, thereby increase the surface area for mass transfer and the effectiveness of soil vapor extraction remediation.

  4. Enhancement of stability of various nZVI suspensions used in groundwater remediation with environmentally friendly organic stabilizers

    NASA Astrophysics Data System (ADS)

    Schmid, Doris; Wagner, Stephan; Velimirović, Milica; Laumann, Susanne; Micić, Vesna; Hofmann, Thilo

    2014-05-01

    The use of nanoscale zero-valent iron (nZVI) particles for in situ remediation of polluted soil and groundwater has been shown as one of the most promising techniques [1]. The success of this technology depends on the mobility, reactivity, and longevity of nZVI particles. The mobility of nZVI particles depends on the properties of the single particles, stability of the particle suspension, and the aquifer material [1,2]. In order to enhance the mobility of nZVI, the mobility-decisive properties of the nZVI particles in suspension such as concentration, size distribution, surface charge, and sedimentation rate have to be investigated and optimized. Previous studies showed that pristine nZVI particles aggregate rapidly in water, reducing the particles radius of influence after injection [3]. In order to prevent aggregation and sedimentation of the nZVI particles, and consequently improve the stability of nZVI suspension and therefore the mobility of the nZVI particles, surface stabilizers can be used to provide electrostatic repulsion and steric or electrosteric stabilization [3,4]. The objective of this lab-scale study is to investigate the potential for enhancing the stability of different nZVI suspensions by means of environmentally friendly organic stabilizers, including carboxymethyl cellulose, pectin, alginate, xanthan, and guar gum. The different nZVI particles used included pristine and polyacrylic acid-coated nZVI particles provided in suspension (Nanofer 25 and Nanofer 25S, respectively, NANOIRON s.r.o., Czech Republic), air-stable nZVI particles (Nanofer Star, (NANOIRON s.r.o., Czech Republic), and milled iron flakes (UVR-FIA, Germany). In order to study the enhancement of nZVI stability (1 g L-1 total iron) different concentrations of organic stabilizers (1-20 wt.%) were applied in these nZVI suspensions. Each nZVI suspension was freshly prepared and treated for 10 minutes with Ultra-Turrax (15 000 rpm) and 10 minutes ultrasonic bath prior to

  5. [Interactive effect of spent mushroom compost and rhamnolipids to enhance the efficiency of alfalfa remediation of aged PAHs contaminated soil].

    PubMed

    Zhang, Jing; Lin, Xian-Gui; Li, Xuan-Zhen; Yin, Rui

    2010-10-01

    Polycyclic aromatic hydrocarbons (PAHs) are a group of the most widespread organic pollutants, which distributed widely in soil and sediment. Pot experiment was conducted to improve efficiency of phytoremediation using alfalfa (Medicago sativa L.) in aged PAHs contaminated soil by introducing spent mushroom compost and rhamnolipids. Plant biomass, PAHs concentrations, number of soil microorganism, soil enzyme activity and soil microbial functional diversity were determined after 60 days of alfalfa growth. The results showed that within 60 days, removal ratio of PAHs in treatment of alfalfa alone (AL) reached to 14.43%, while removal ratio of PAHs in treatments of "GZ + RH0.5, + AL" and "GZ + RH1.0 + AL" reached to 32.64% and 36.95%, which were 115.45% and 156.06% higher than that of phytoremediation. Contrasted to the control, the treatment of "GZ + RH1.0 + AL" had more plant biomass than others, shoot and root dry weight were 1.05 g/pot and 0.20 g/pot, respectively. During the process of phytoremediation, the number of soil bacteria and fungi were greatly increased by "GZ + RH1.0 + AL" and reached to 31.37 x 10(6) CFU x g(-1) and 5.86 x 10(6) CFU x g(-1), especially the number of PAHs-degrading bacteria reached to 39.57 x 10(5) MPN x g(-1), which were 29 times more than control treatment and 4 times more than treatment of alfalfa alone (AL). Moreover, soil dehydrogenase activity and the functional diversity of soil microbial community were increased significantly by the treatment of "GZ + RH1.0 + AL", respectively. Therefore, interaction of spent mushroom compost and rhamnolipids to enhance the phytoremediation efficiency had satisfied results in removal aged PAHs from an agricultural soil, the feasibility of this method needed to be further proved by large-area scale field experiment.

  6. Feuerstein's Mediated Learning Experience as a Vehicle for Enhancing Cognitive Functioning of Remedial School Learners in South Africa

    ERIC Educational Resources Information Center

    Seabi, Joseph

    2012-01-01

    The study investigated the effects of mediated learning experience (MLE) intervention on Remedial school learners' cognitive functioning as measured by the Ravens Coloured Progressive Matrices (RCPM). The sample comprised 67 participants (males = 35; females = 32; mean age = 11.8) from Grade 4 through to Grade 7. Participants were given the RCPM…

  7. SIMPLE ANALYTICAL MODEL FOR HEAT FLOW IN FRACTURES-APPLICATION TO STEAM ENHANCED REMEDIATION CONDUCTED IN FRACTURED ROCK

    EPA Science Inventory

    Remediation of fractured rock sites contaminated by non-aqueous phase liquids has long been recognized as the most difficult undertaking of any site clean-up. Recent pilot studies conducted at the Edwards Air Force Base in California and the former Loring Air Force Base in Maine ...

  8. SIMPLE ANALYTICAL MODEL FOR HEAT FLOW IN FRACTURES - APPLICATION TO STEAM ENHANCED REMEDIATION CONDUCTED IN FRACTURED ROCK

    EPA Science Inventory

    Remediation of fractured rock sites contaminated by non-aqueous phase liquids has long been recognized as the most difficult undertaking of any site clean-up. Recent pilot studies conducted at the Edwards Air Force Base in California and the former Loring Air Force Base in Maine ...

  9. Cognitive Remediation in Schizophrenia

    PubMed Central

    Kaneko, Yoshio

    2012-01-01

    Cognitive deficits in schizophrenia are pervasive, severe, and largely independent of the positive and negative symptoms of the illness. These deficits are increasingly considered to be core features of schizophrenia with evidence that the extent of cognitive impairment is the most salient predictor of daily functioning. Unfortunately, current schizophrenia treatment has been limited in addressing the cognitive deficits of the illness. Alterations in neuroplasticity are hypothesized to underpin these cognitive deficits, though preserved neuroplasticity may offer an avenue towards cognitive remediation. Key neuroplastic principles to consider in designing remediation interventions include ensuring sufficient intensity and duration of remediation programs, "bottom-up" training that proceeds from simple to complex cognitive processes, and individual tailoring of remediation regimens. We discuss several cognitive remediation programs, including cognitive enhancement therapy, which embrace these principles to target neurocognitive and social cognitive improvements and which havebeen demonstrated to be effective in schizophrenia. Future directions in cognitive remediation research include potential synergy with pharmacologic treatment, non-invasive stimulation techniques, and psychosocial interventions, identification of patient characteristics that predict outcome with cognitive remediation, and increasing the access to these interventions in front-line settings. PMID:23430145

  10. Functional diversity enhances the resistance of ecosystem multifunctionality to aridity in Mediterranean drylands

    PubMed Central

    Valencia-Gómez, Enrique; Maestre, Fernando T.; Le Bagousse-Pinguet, Yoann; Quero, José Luis; Tamme, Riin; Börger, Luca; García-Gómez, Miguel; Gross, Nicolas

    2015-01-01

    SUMMARY We used a functional trait-based approach to assess the impacts of aridity and shrub encroachment on the functional structure of Mediterranean dryland communities (functional diversity and community-weighted mean trait values [CWM]), and to evaluate how these functional attributes ultimately affect multifunctionality (i.e., the provision of several ecosystem functions simultaneously). Shrub encroachment (the increase in the abundance/cover of shrubs) is a major land cover change that is taking place in grasslands worldwide. Studies conducted on drylands have reported positive or negative impacts of shrub encroachment depending on the functions and the traits of the sprouting or non-sprouting shrub species considered. Functional diversity and CWM were equally important as drivers of multifunctionality responses to both aridity and shrub encroachment. Size traits (e.g., vegetative height or lateral spread) and leaf traits (e.g., specific leaf area and leaf dry matter content) captured the effect of shrub encroachment on multifunctionality with a relative high accuracy (r2=0.63). Functional diversity also improved the resistance of multifunctionality along the aridity gradient studied. Maintaining and enhancing functional diversity in plant communities may help to buffer negative effects of ongoing global environmental change on dryland multifunctionality. PMID:25615801

  11. Remediation of organochlorine pesticides (OCPs) contaminated site by successive methyl-β-cyclodextrin (MCD) and sunflower oil enhanced soil washing - Portulaca oleracea L. cultivation.

    PubMed

    Ye, Mao; Sun, Mingming; Hu, Feng; Kengara, Fredrick Orori; Jiang, Xin; Luo, Yongming; Yang, Xinlun

    2014-06-01

    An innovative ex situ soil washing technology was developed in this study to remediate organochlorine pesticides (OCPs)-contaminated site. Elevated temperature (50 °C) combined with ultrasonication (35 kHz, 30 min) at 25 g L(-1) methyl-β-cyclodextrin and 100 mL L(-1) sunflower oil were effective in extracting OCPs from the soil. After four successive washing cycles, the removal efficiency for total OCPs, DDTs, endosulfans, 1,2,3,4,5,6-hexachlorocyclohexanes, heptachlors, and chlordanes were all about 99%. The 4th washed soil with 3 months cultivation of Portulaca oleracea L. and nutrient addition significantly increase (p<0.05) the number, biomass carbon, nitrogen, and functioning diversity of soil microorganisms. This implied that the microbiological functioning of the soil was at least partially restored. This combined cleanup strategy proved to be effective and environmental friendly.

  12. Large-scale River Restoration Enhances Geomorphological Diversity and Benthic Biodiversity

    NASA Astrophysics Data System (ADS)

    Matthaei, C. D.; Diehl, S.; Huber, H.

    2005-05-01

    An 8-km stretch of the River Isar is being restored within the city limits of Munich; this is one of the largest river restoration projects in Europe. We evaluated effects of the restoration on geomorphological parameters and river invertebrates. Before and after restoration of a channelised 1-km reach, we investigated this reach and two reference reaches (another channelised reach and a natural reach). On four dates before and six dates after restoration, we measured detailed transects of bed topography at each reach to document changes in bed morphology. Sampling periods included 6 (before) and 11 (after) bed-moving floods. On three dates each before and after restoration, we also collected quantitative invertebrate samples. Before restoration, geomorphological diversity (the spatial variability of water depth) was lower at both channelised reaches than at the natural reach. After restoration, diversity at the restored reach became as high as at the natural reach but remained low at the channelised reach. Invertebrate species richness and richness of mayflies, stoneflies and caddis flies also increased at the restored reach relative to both reference reaches, probably as a consequence of enhanced geomorphological diversity, which provided a more distinct spatial patchwork of differing abiotic habitat conditions for invertebrates.

  13. Limiting resources in sessile systems: food enhances diversity and growth of suspension feeders despite available space.

    PubMed

    Svensson, Robin J; Marshall, Dustin J

    2015-03-01

    Much of our understanding of competition comes trom onservations in sessue systems, such as rainforests and marine invertebrate communities. In terrestrial systems, sessile species often compete for multiple limiting resources (i.e., space, light, and nutrients), but in marine systems, space is viewed as the primary or sole limiting resource. Competition theory, on the other hand, suggests that competition for a single limiting resource is unlikely to maintain high species diversity, but manipulative tests of competition for other resources in marine benthic systems are exceedingly rare. Here, we manipulate the availability of food for a classic system, marine sessile invertebrate communities, and investigate the effects on species diversity, abundance, and composition during early succession as well as on the growth of bryozoan populations in the field. We found the number of species to be greater, available space to be lower, and the community composition to be different in assemblages subjected to increased food availability compared to controls. Similarly, laboratory-settled bryozoans deployed into the field grew more in the presence of enhanced food. Our results suggest that food can act as a limiting resource, affecting both diversity and abundance, even when bare space is still available in hard-substratum communities. Consequently, broadening the view of resource limitation beyond solely space may increase our understanding and predictability of marine sessile systems.

  14. Limiting resources in sessile systems: food enhances diversity and growth of suspension feeders despite available space.

    PubMed

    Svensson, Robin J; Marshall, Dustin J

    2015-03-01

    Much of our understanding of competition comes trom onservations in sessue systems, such as rainforests and marine invertebrate communities. In terrestrial systems, sessile species often compete for multiple limiting resources (i.e., space, light, and nutrients), but in marine systems, space is viewed as the primary or sole limiting resource. Competition theory, on the other hand, suggests that competition for a single limiting resource is unlikely to maintain high species diversity, but manipulative tests of competition for other resources in marine benthic systems are exceedingly rare. Here, we manipulate the availability of food for a classic system, marine sessile invertebrate communities, and investigate the effects on species diversity, abundance, and composition during early succession as well as on the growth of bryozoan populations in the field. We found the number of species to be greater, available space to be lower, and the community composition to be different in assemblages subjected to increased food availability compared to controls. Similarly, laboratory-settled bryozoans deployed into the field grew more in the presence of enhanced food. Our results suggest that food can act as a limiting resource, affecting both diversity and abundance, even when bare space is still available in hard-substratum communities. Consequently, broadening the view of resource limitation beyond solely space may increase our understanding and predictability of marine sessile systems. PMID:26236877

  15. Enhanced abundance and diversity of ammonia-oxidizing Archaea in the Pearl River estuary

    NASA Astrophysics Data System (ADS)

    Xie, W.; Zhang, C. L.; Wang, P.; Zhou, X.; Guo, W.

    2014-12-01

    Thaumarchaeota are recently recognized as an important group of Archaea that can perform aerobic oxidation of ammonia in a wide range of environments. The goal of this study was to evaluate changes in abundance and diversity of planktonic ammonia-oxidizing Archaea (e.g., Thaumarchaeota) along a salinity gradient from the lower Pearl River to the northern South China Sea. Quantitative PCR and sequencing of total archaeal 16S rRNA gene and the archaeal amoA gene were performed on suspended particulate organic matter collected in different seasons from the freshwater to the ocean water. Total amoA gene copies and relative abundance of Thaumarchaeota all peaked in the estuary where salinity ranged between 4.5‰ and 26.7‰. The diversity of archaeal amoA gene was also highest in the estuary. Seasonality and SiO32- appear to be two major factors affecting the distribution of subclusters of archaeal amoA genes. For example, Nitrosopumilus subcluster 7.1 was most abundant in winter in fresh water, whereas Nitrososphaera were more abundant in summer. Samples collected from the area around Wanshan Island, which is located at the outermost part of the Pearl River estuary, had high abundance of unclassified archaeal amoA genes, suggesting some new groups of Thaumarchaeota might inhabit this water body. Overall, the high abundance and diversity of Thaumarchaeota in the Pearl River estuary may indicate enhanced role of AOA in nitrogen cycle in this dynamic ecosystem.

  16. Concerning Remediation

    ERIC Educational Resources Information Center

    Pace, John P.

    1977-01-01

    The author argues that the key to teaching remedial mathematics is to persuade students to believe that they will advance intellectually by learning mathematics, and that this advance will increase the possibilities open to them. (SD)

  17. X-231A demonstration of in-situ remediation of DNAPL compounds in low permeability media by soil fracturing with thermally enhanced mass recovery or reactive barrier destruction

    SciTech Connect

    Siegrist, R.L. |; Lowe, K.S.; Murdoch, L.D. |; Slack, W.W.; Houk, T.C.

    1998-03-01

    The overall goal of the program of activities is to demonstrate robust and cost-effective technologies for in situ remediation of DNAPL compounds in low permeability media (LPM), including adaptations and enhancements of conventional technologies to achieve improved performance for DNAPLs in LPM. The technologies sought should be potential for application at simple, small sites (e.g., gasoline underground storage tanks) as well as at complex, larger sites (e.g., DOE land treatment units). The technologies involved in the X-231A demonstration at Portsmouth Gaseous Diffusion Plant (PORTS) utilized subsurface manipulation of the LPM through soil fracturing with thermally enhanced mass recovery or horizontal barrier in place destruction. To enable field evaluation of these approaches, a set of four test cells was established at the X-231A land treatment unit at the DOE PORTS plant in August 1996 and a series of demonstration field activities occurred through December 1997. The principal objectives of the PORTS X-231A demonstration were to: determine and compare the operational features of hydraulic fractures as an enabling technology for steam and hot air enhanced soil vapor extraction and mass recovery, in situ interception and reductive destruction by zero valent iron, and in situ interception and oxidative destruction by potassium permanganate; determine the interaction of the delivered agents with the LPM matrix adjacent to the fracture and within the fractured zone and assess the beneficial modifications to the transport and/or reaction properties of the LPM deposit; and determine the remediation efficiency achieved by each of the technology strategies.

  18. Partnership to Enhance Diversity in Marine Geosciences: Holocene Climate and Anthropogenic Changes from Long Island Sound, NY

    NASA Astrophysics Data System (ADS)

    McHugh, C. M.; Zheng, Y.; Kohfeld, K. E.; Marchese, P.; Cormier, M.; Warkentine, B.

    2005-12-01

    This project, sponsored by the National Science Foundation, Opportunities to Enhance Diversity in the Geosciences Division, will develop a program based on multidisciplinary investigations of Long Island Sound, as a vehicle to enhance diversity in geosciences. The program includes a curriculum centered on geosciences with a substantial field and laboratory component. Students will participate in a one-week oceanographic expedition to Long Island Sound aboard the R/V Cape Henlopen and in day trips using SUNY Maritime College's R/V Alexanderson. The goal is to illustrate the dominant physical processes in an urban coastal area by using a variety of oceanographic mapping techniques, such as multibeam bathymetric mapping, sediment and water sampling, and current profiling. The working hypothesis is that New York City students will be attracted to geosciences through an integrated field and research experience which familiarizes them with their own environment. Furthermore, they will be introduced to solving geoscience problems in a hands-on manner while receiving one-on-one mentoring in a supportive environment. Strong support exists from the City University of New York (CUNY) at the graduate level through MAGNET fellowships. At the undergraduate level, the geoscience curriculum fulfills a science requirement for completion of a BA in geosciences. Support also exists from the "Alliance for Minority Participation" (AMP), a program supported by the National Science Foundation and in which Queens College (QC) and CUNY participate, and the "Search for Education, Elevation, and Knowledge" (SEEK), a QC program designed to provide educational opportunities for academically motivated students who need substantial financial assistance to attend college. The main scientific objectives are 1) to evaluate the impact of anthropogenic activities through studies of the waters, plankton, and sediments and to propose measures for their remediation, and 2) to begin to assess long

  19. A demonstration of the applicability of implementing the enhanced Remedial Action Priority System (RAPS) for environmental releases

    SciTech Connect

    Whelan, G.; Droppo, J.G. Jr.; Strenge, D.L.; Walter, M.B.; Buck, J.W.

    1989-12-01

    The Remedial Action Priority System (RAPS) and the Multimedia Environmental Pollutant Assessment System (MEPAS) were developed to prioritize problems associated with potential releases of hazardous chemical and radioactive materials in a scientific and objective manner based on limited site information. This report documents the model testing efforts of the RAPS/MEPAS methodology for the atmospheric, surface water, groundwater, and exposure components. Comparisons are given of model outputs with measured data at three sites: the US Department of Energy's Mound facility in Ohio and Hanford facility in Washington, and a chromium-cadmium plating site in New York. The results show that the simulated magnitudes, spacial and temporal trends, and distributions of contaminants corresponded well with the measured data. 25 refs., 86 figs., 26 tabs.

  20. Reliability enhancement of APR + diverse protection system regarding common cause failures

    SciTech Connect

    Oh, Y. G.; Kim, Y. M.; Yim, H. S.; Lee, S. J.

    2012-07-01

    The Advanced Power Reactor Plus (APR +) nuclear power plant design has been developed on the basis of the APR1400 (Advanced Power Reactor 1400 MWe) to further enhance safety and economics. For the mitigation of Anticipated Transients Without Scram (ATWS) as well as Common Cause Failures (CCF) within the Plant Protection System (PPS) and the Emergency Safety Feature - Component Control System (ESF-CCS), several design improvement features have been implemented for the Diverse Protection System (DPS) of the APR + plant. As compared to the APR1400 DPS design, the APR + DPS has been designed to provide the Safety Injection Actuation Signal (SIAS) considering a large break LOCA accident concurrent with the CCF. Additionally several design improvement features, such as channel structure with redundant processing modules, and changes of system communication methods and auto-system test methods, are introduced to enhance the functional reliability of the DPS. Therefore, it is expected that the APR + DPS can provide an enhanced safety and reliability regarding possible CCF in the safety-grade I and C systems as well as the DPS itself. (authors)

  1. GROUND WATER ISSUE: HOW HEAT CAN ENHANCE IN-SITU SOIL AND AQUIFER REMEDIATION: IMPORTANT CHEMICAL PROPERTIES & GUIDANCE ON CHOOSING THE APPROPRIATE TECHNIQUE

    EPA Science Inventory

    The purpose of this Issue Paper and the three companion Issue Papers (Davis, 1997a, b, c) is to provide to those involved in assessing remediation technologies some basic information on the thermal remediation techniques.

  2. Herbivory and drought interact to enhance spatial patterning and diversity in a savanna understory.

    PubMed

    Porensky, Lauren M; Wittman, Sarah E; Riginos, Corinna; Young, Truman P

    2013-10-01

    The combination of abiotic stress and consumer stress can have complex impacts on plant community structure. Effective conservation and management of semi-arid ecosystems requires an understanding of how different stresses interact to structure plant communities. We explored the separate and combined impacts of episodic drought, livestock grazing, and wild ungulate herbivory on species co-occurrence and diversity patterns in a relatively productive, semi-arid Acacia savanna. Specifically, we analyzed 9 years of biannual plant community data from the Kenya long-term exclosure experiment, a broad-scale manipulative experiment that has excluded different combinations of large mammalian herbivores from 18 4-ha plots since 1995. During droughts, we observed low species diversity and random species co-occurrence patterns. However, when rain followed a major drought, areas exposed to moderate cattle grazing displayed high species diversity and evidence of significant species aggregation. These patterns were not apparent in the absence of cattle, even if other large herbivores were present. To explore possible mechanisms, we examined patterns separately for common and rare species. We found that aggregation patterns were likely driven by rare species responding similarly to the availability of open micro-sites. Our results indicate that in a productive, fire-suppressed savanna, the combination of periodic drought and moderate cattle grazing can enhance plant biodiversity and fine-scale spatial heterogeneity by opening up space for species that are otherwise rare or cryptic. Our findings also emphasize that domestic herbivores can have significantly stronger impacts on plant community dynamics than wild herbivores, even in an ecosystem with a long history of grazing.

  3. Bee species diversity enhances productivity and stability in a perennial crop.

    PubMed

    Rogers, Shelley R; Tarpy, David R; Burrack, Hannah J

    2014-01-01

    Wild bees provide important pollination services to agroecoystems, but the mechanisms which underlie their contribution to ecosystem functioning--and, therefore, their importance in maintaining and enhancing these services-remain unclear. We evaluated several mechanisms through which wild bees contribute to crop productivity, the stability of pollinator visitation, and the efficiency of individual pollinators in a highly bee-pollination dependent plant, highbush blueberry. We surveyed the bee community (through transect sampling and pan trapping) and measured pollination of both open- and singly-visited flowers. We found that the abundance of managed honey bees, Apis mellifera, and wild-bee richness were equally important in describing resulting open pollination. Wild-bee richness was a better predictor of pollination than wild-bee abundance. We also found evidence suggesting pollinator visitation (and subsequent pollination) are stabilized through the differential response of bee taxa to weather (i.e., response diversity). Variation in the individual visit efficiency of A. mellifera and the southeastern blueberry bee, Habropoda laboriosa, a wild specialist, was not associated with changes in the pollinator community. Our findings add to a growing literature that diverse pollinator communities provide more stable and productive ecosystem services. PMID:24817218

  4. Bee Species Diversity Enhances Productivity and Stability in a Perennial Crop

    PubMed Central

    Rogers, Shelley R.; Tarpy, David R.; Burrack, Hannah J.

    2014-01-01

    Wild bees provide important pollination services to agroecoystems, but the mechanisms which underlie their contribution to ecosystem functioning—and, therefore, their importance in maintaining and enhancing these services—remain unclear. We evaluated several mechanisms through which wild bees contribute to crop productivity, the stability of pollinator visitation, and the efficiency of individual pollinators in a highly bee-pollination dependent plant, highbush blueberry. We surveyed the bee community (through transect sampling and pan trapping) and measured pollination of both open- and singly-visited flowers. We found that the abundance of managed honey bees, Apis mellifera, and wild-bee richness were equally important in describing resulting open pollination. Wild-bee richness was a better predictor of pollination than wild-bee abundance. We also found evidence suggesting pollinator visitation (and subsequent pollination) are stabilized through the differential response of bee taxa to weather (i.e., response diversity). Variation in the individual visit efficiency of A. mellifera and the southeastern blueberry bee, Habropoda laboriosa, a wild specialist, was not associated with changes in the pollinator community. Our findings add to a growing literature that diverse pollinator communities provide more stable and productive ecosystem services. PMID:24817218

  5. Co-Cultivation—A Powerful Emerging Tool for Enhancing the Chemical Diversity of Microorganisms

    PubMed Central

    Marmann, Andreas; Aly, Amal H.; Lin, Wenhan; Wang, Bingui; Proksch, Peter

    2014-01-01

    Marine-derived bacteria and fungi are promising sources of novel bioactive compounds that are important for drug discovery programs. However, as encountered in terrestrial microorganisms there is a high rate of redundancy that results in the frequent re-discovery of known compounds. Apparently only a part of the biosynthetic genes that are harbored by fungi and bacteria are transcribed under routine laboratory conditions which involve cultivation of axenic microbial strains. Many biosynthetic genes remain silent and are not expressed in vitro thereby seriously limiting the chemical diversity of microbial compounds that can be obtained through fermentation. In contrast to this, co-cultivation (also called mixed fermentation) of two or more different microorganisms tries to mimic the ecological situation where microorganisms always co-exist within complex microbial communities. The competition or antagonism experienced during co-cultivation is shown to lead to a significantly enhanced production of constitutively present compounds and/or to an accumulation of cryptic compounds that are not detected in axenic cultures of the producing strain. This review highlights the power of co-cultivation for increasing the chemical diversity of bacteria and fungi drawing on published studies from the marine and from the terrestrial habitat alike. PMID:24549204

  6. Organic amendments enhance microbial diversity and abundance of functional genes in Australian Soils

    NASA Astrophysics Data System (ADS)

    Aldorri, Sind; McMillan, Mary; Pereg, Lily

    2016-04-01

    Food and cash crops play important roles in Australia's economy with black, grey and red clay soil, widely use for growing cotton, wheat, corn and other crops in rotation. While the majority of cotton growers use nitrogen and phosphate fertilizers only in the form of agrochemicals, a few experiment with the addition of manure or composted plant material before planting. We hypothesized that the use of such organic amendments would enhance the soil microbial function through increased microbial diversity and abundance, thus contribute to improved soil sustainability. To test the hypothesis we collected soil samples from two cotton-growing farms in close geographical proximity and with mostly similar production practices other than one grower has been using composted plants as organic amendment and the second farmer uses only agrochemicals. We applied the Biolog Ecoplate system to study the metabolic signature of microbial communities and used qPCR to estimate the abundance of functional genes in the soil. The soil treated with organic amendments clearly showed higher metabolic activity of a more diverse range of carbon sources as well as higher abundance of genes involved in the nitrogen and phosphorous cycles. Since microbes undertake a large number of soil functions, the use of organic amendments can contribute to the sustainability of agricultural soils.

  7. Stabilization of Fe(0) nanoparticles with silica fume for enhanced transport and remediation of hexavalent chromium in water and soil.

    PubMed

    Li, Yongchao; Li, Tielong; Jini, Zhaohui

    2011-01-01

    Effective in situ remediation of Cr(VI) in groundwater requires the successful delivery of reactive iron particles to the subsurface. Fe(0) nanoparticles (20-110 nm diameter) supported on silica fume were synthesized by borohydride reduction of an aqueous iron salt in the presence of a support material. The experimental result showed that attachment of Fe(0) nanoparticles on the commercial available sub-micrometer silica fume prevented them from aggregation while maintaining the particle reactivity. When the Fe(0) concentration was 0.4 g/L, 88.00% of 40 mg/L Cr(VI) was removed by silica fume-supported Fe(0) nanoparticles (SF-Fe(0) in 120 min, 22.55% higher than unsupported Fe(0). Furthermore, transport experiments confirmed that almost all unsupported Fe(0) was retained, whereas 51.50% and 38.29% of SF-Fe(0) were eluted from the vertical and horizontal sand column, respectively. Additionally, the effect of solution ionic strength on the transport ability of SF-Fe(0) was evaluated. The result showed that increase in the salt concentration led to a decrease in the mobility and also the divalent ion Ca2+ had a greater effect than that of monovalent ion Na+.

  8. Teaching Communication Ethics and Diversity: Using Technology and Community Engagement to Enhance Learning

    ERIC Educational Resources Information Center

    Swenson-Lepper, Tammy

    2012-01-01

    The workforce in the United States is becoming more diverse. To help students prepare to work and live in a diverse society, the author developed a lower-division course called "Communication Ethics and Diversity." After this course, students should be able to: (1) define diversity and communication ethics; (2) understand a variety of approaches…

  9. Enhancing majority members' pro-diversity beliefs in small teams: the facilitating effect of self-anchoring.

    PubMed

    van Veelen, Ruth; Otten, Sabine; Hansen, Nina

    2014-01-01

    Majority members often react negatively to efforts to stimulate diversity. An important reason for this is that in diverse groups, majority members' own group bond is typically based on perceived prototypicality, which serves to disregard those who are different. In the present research we investigate how majority members' pro-diversity beliefs may be enhanced, by experimentally manipulating how the self is cognitively defined in relation to a diverse group. Specifically, we hypothesize that majority members' focus on the personal self (i.e., self-anchoring) rather than the social self (i.e., self-stereotyping) when creating a group bond may facilitate their pro-diversity beliefs and positive attitudes toward minority members. In two experiments we manipulated self-anchoring and self-stereotyping via mindset priming among ethnic majority members in diverse teams. As expected, results showed that relative to self-stereotyping, majority members' self-anchoring enhanced pro-diversity beliefs and positive attitudes toward minority members.

  10. Acquisition of glial cells missing 2 Enhancers Contributes to a Diversity of Ionocytes in Zebrafish

    PubMed Central

    Shono, Takanori; Kurokawa, Daisuke; Miyake, Tsutomu; Okabe, Masataka

    2011-01-01

    Glial cells missing 2 (gcm2) encoding a GCM-motif transcription factor is expressed in the parathyroid in amniotes. In contrast, gcm2 is expressed in pharyngeal pouches (a homologous site of the parathyroid), gills, and H+-ATPase–rich cells (HRCs), a subset of ionocytes on the skin surface of the teleost fish zebrafish. Ionocytes are specialized cells that are involved in osmotic homeostasis in aquatic vertebrates. Here, we showed that gcm2 is essential for the development of HRCs and Na+-Cl− co-transporter–rich cells (NCCCs), another subset of ionocytes in zebrafish. We also identified gcm2 enhancer regions that control gcm2 expression in ionocytes of zebrafish. Comparisons of the gcm2 locus with its neighboring regions revealed no conserved elements between zebrafish and tetrapods. Furthermore, We observed gcm2 expression patterns in embryos of the teleost fishes Medaka (Oryzias latipes) and fugu (Fugu niphobles), the extant primitive ray-finned fishes Polypterus (Polypterus senegalus) and sturgeon (a hybrid of Huso huso × Acipenser ruhenus), and the amphibian Xenopus (Xenopus laevis). Although gcm2-expressing cells were observed on the skin surface of Medaka and fugu, they were not found in Polypterus, sturgeon, or Xenopus. Our results suggest that an acquisition of enhancers for the expression of gcm2 contributes to a diversity of ionocytes in zebrafish during evolution. PMID:21858216

  11. Evaluation of the Eological Management and Enhancement Alernative for Remediation of the K1007-P1 Pond

    SciTech Connect

    Peterson, M.J.

    2005-10-31

    An evaluation of the human and ecological risks associated with the P1 Pond and surrounding environs was conducted as part of the ETTP Site-Wide Remedial Investigation. The RI provides the basis for the focus on PCBs as the most important unacceptable risk to human and ecological health in the pond. Other P1 contaminants, media, or pathways of risk to receptors are identified in the RI, but are not addressed as a major risk reduction goal for the ETTP Site-Wide Feasibility Study. Therefore, the goal of the Ecological Management alternative is to reduce unacceptable risks associated with PCBs in fish. Many of the actions proposed for this alternative, however, are likely to reduce risks associated with other contaminants and their pathways. The high PCB concentrations in fish from the P1 Pond are most certainly due in part to the current ecological condition of the pond that maximizes PCB biomagnification. This basic assumption and the factors contributing to it were evaluated by conducting an intensive field study of the P1 Pond in the summer of 2004 (for a thorough presentation of current P1 Pond biological conditions, see Peterson et al. 2005). Major hypotheses regarding the P1 Pond's current fish community, PCB fate and transport processes, pond vegetation, and limnological conditions that contribute to the high PCB levels in fish were validated by the study (Appendix A), The results of the 2004 ecological assessment, in concert with long-term datasets obtained as part of the ETTP Biological Monitoring and Abatement Program (BMAP) and recent abiotic sampling for the RI, provide the basis for the assessment of current conditions.

  12. Reimagining Remediation

    ERIC Educational Resources Information Center

    Handel, Stephen J.; Williams, Ronald A.

    2011-01-01

    In 2007, the College Board's Community College Advisory Panel--a group of college presidents that advises the organization's membership on community college issues--asked these authors to write a paper describing effective remedial education programs. They never wrote the paper. The problem was not the lack of dedicated faculty and staff working…

  13. Toxic remediation

    DOEpatents

    Matthews, Stephen M.; Schonberg, Russell G.; Fadness, David R.

    1994-01-01

    What is disclosed is a novel toxic waste remediation system designed to provide on-site destruction of a wide variety of hazardous organic volatile hydrocarbons, including but not limited to halogenated and aromatic hydrocarbons in the vapor phase. This invention utilizes a detoxification plenum and radiation treatment which transforms hazardous organic compounds into non-hazardous substances.

  14. Ensemble of Surrogates-based Optimization for Identifying an Optimal Surfactant-enhanced Aquifer Remediation Strategy at Heterogeneous DNAPL-contaminated Sites

    NASA Astrophysics Data System (ADS)

    Lu, W., Sr.; Xin, X.; Luo, J.; Jiang, X.; Zhang, Y.; Zhao, Y.; Chen, M.; Hou, Z.; Ouyang, Q.

    2015-12-01

    The purpose of this study was to identify an optimal surfactant-enhanced aquifer remediation (SEAR) strategy for aquifers contaminated by dense non-aqueous phase liquid (DNAPL) based on an ensemble of surrogates-based optimization technique. A saturated heterogeneous medium contaminated by nitrobenzene was selected as case study. A new kind of surrogate-based SEAR optimization employing an ensemble surrogate (ES) model together with a genetic algorithm (GA) is presented. Four methods, namely radial basis function artificial neural network (RBFANN), kriging (KRG), support vector regression (SVR), and kernel extreme learning machines (KELM), were used to create four individual surrogate models, which were then compared. The comparison enabled us to select the two most accurate models (KELM and KRG) to establish an ES model of the SEAR simulation model, and the developed ES model as well as these four stand-alone surrogate models was compared. The results showed that the average relative error of the average nitrobenzene removal rates between the ES model and the simulation model for 20 test samples was 0.8%, which is a high approximation accuracy, and which indicates that the ES model provides more accurate predictions than the stand-alone surrogate models. Then, a nonlinear optimization model was formulated for the minimum cost, and the developed ES model was embedded into this optimization model as a constrained condition. Besides, GA was used to solve the optimization model to provide the optimal SEAR strategy. The developed ensemble surrogate-optimization approach was effective in seeking a cost-effective SEAR strategy for heterogeneous DNAPL-contaminated sites. This research is expected to enrich and develop the theoretical and technical implications for the analysis of remediation strategy optimization of DNAPL-contaminated aquifers.

  15. Ensemble of surrogates-based optimization for identifying an optimal surfactant-enhanced aquifer remediation strategy at heterogeneous DNAPL-contaminated sites

    NASA Astrophysics Data System (ADS)

    Jiang, Xue; Lu, Wenxi; Hou, Zeyu; Zhao, Haiqing; Na, Jin

    2015-11-01

    The purpose of this study was to identify an optimal surfactant-enhanced aquifer remediation (SEAR) strategy for aquifers contaminated by dense non-aqueous phase liquid (DNAPL) based on an ensemble of surrogates-based optimization technique. A saturated heterogeneous medium contaminated by nitrobenzene was selected as case study. A new kind of surrogate-based SEAR optimization employing an ensemble surrogate (ES) model together with a genetic algorithm (GA) is presented. Four methods, namely radial basis function artificial neural network (RBFANN), kriging (KRG), support vector regression (SVR), and kernel extreme learning machines (KELM), were used to create four individual surrogate models, which were then compared. The comparison enabled us to select the two most accurate models (KELM and KRG) to establish an ES model of the SEAR simulation model, and the developed ES model as well as these four stand-alone surrogate models was compared. The results showed that the average relative error of the average nitrobenzene removal rates between the ES model and the simulation model for 20 test samples was 0.8%, which is a high approximation accuracy, and which indicates that the ES model provides more accurate predictions than the stand-alone surrogate models. Then, a nonlinear optimization model was formulated for the minimum cost, and the developed ES model was embedded into this optimization model as a constrained condition. Besides, GA was used to solve the optimization model to provide the optimal SEAR strategy. The developed ensemble surrogate-optimization approach was effective in seeking a cost-effective SEAR strategy for heterogeneous DNAPL-contaminated sites. This research is expected to enrich and develop the theoretical and technical implications for the analysis of remediation strategy optimization of DNAPL-contaminated aquifers.

  16. Cattle Manure Enhances Methanogens Diversity and Methane Emissions Compared to Swine Manure under Rice Paddy.

    PubMed

    Kim, Sang Yoon; Pramanik, Prabhat; Bodelier, Paul L E; Kim, Pil Joo

    2014-01-01

    Livestock manures are broadly used in agriculture to improve soil quality. However, manure application can increase the availability of organic carbon, thereby facilitating methane (CH4) production. Cattle and swine manures are expected to have different CH4 emission characteristics in rice paddy soil due to the inherent differences in composition as a result of contrasting diets and digestive physiology between the two livestock types. To compare the effect of ruminant and non-ruminant animal manure applications on CH4 emissions and methanogenic archaeal diversity during rice cultivation (June to September, 2009), fresh cattle and swine manures were applied into experimental pots at 0, 20 and 40 Mg fresh weight (FW) ha-1 in a greenhouse. Applications of manures significantly enhanced total CH4 emissions as compared to chemical fertilization, with cattle manure leading to higher emissions than swine manure. Total organic C contents in cattle (466 g kg-1) and swine (460 g kg-1) manures were of comparable results. Soil organic C (SOC) contents were also similar between the two manure treatments, but dissolved organic C (DOC) was significantly higher in cattle than swine manure. The mcrA gene copy numbers were significantly higher in cattle than swine manure. Diverse groups of methanogens which belong to Methanomicrobiaceae were detected only in cattle-manured but not in swine-manured soil. Methanogens were transferred from cattle manure to rice paddy soils through fresh excrement. In conclusion, cattle manure application can significantly increase CH4 emissions in rice paddy soil during cultivation, and its pretreatment to suppress methanogenic activity without decreasing rice productivity should be considered. PMID:25494364

  17. Cattle Manure Enhances Methanogens Diversity and Methane Emissions Compared to Swine Manure under Rice Paddy

    PubMed Central

    Kim, Sang Yoon; Pramanik, Prabhat; Bodelier, Paul L. E.; Kim, Pil Joo

    2014-01-01

    Livestock manures are broadly used in agriculture to improve soil quality. However, manure application can increase the availability of organic carbon, thereby facilitating methane (CH4) production. Cattle and swine manures are expected to have different CH4 emission characteristics in rice paddy soil due to the inherent differences in composition as a result of contrasting diets and digestive physiology between the two livestock types. To compare the effect of ruminant and non-ruminant animal manure applications on CH4 emissions and methanogenic archaeal diversity during rice cultivation (June to September, 2009), fresh cattle and swine manures were applied into experimental pots at 0, 20 and 40 Mg fresh weight (FW) ha−1 in a greenhouse. Applications of manures significantly enhanced total CH4 emissions as compared to chemical fertilization, with cattle manure leading to higher emissions than swine manure. Total organic C contents in cattle (466 g kg−1) and swine (460 g kg−1) manures were of comparable results. Soil organic C (SOC) contents were also similar between the two manure treatments, but dissolved organic C (DOC) was significantly higher in cattle than swine manure. The mcrA gene copy numbers were significantly higher in cattle than swine manure. Diverse groups of methanogens which belong to Methanomicrobiaceae were detected only in cattle-manured but not in swine-manured soil. Methanogens were transferred from cattle manure to rice paddy soils through fresh excrement. In conclusion, cattle manure application can significantly increase CH4 emissions in rice paddy soil during cultivation, and its pretreatment to suppress methanogenic activity without decreasing rice productivity should be considered. PMID:25494364

  18. Phyto-enhanced remediation of soil co-contaminated with lead and diesel fuel using biowaste and Dracaena reflexa: A laboratory study.

    PubMed

    Dadrasnia, Arezoo; Pariatamby, Agamuthu

    2016-03-01

    In phytoremediation of co-contaminated soil, the simultaneous and efficient remediation of multiple pollutants is a major challenge rather than the removal of pollutants. A laboratory-scale experiment was conducted to investigate the effect of 5% addition of each of three different organic waste amendments (tea leaves, soy cake, and potato skin) to enhance the phytoaccumulation of lead (60 mg kg(-1)) and diesel fuel (25,000 mg kg(-1)) in co-contaminated soil by Dracaena reflexa Lam for a period of 180 day. The highest rate of oil degradation was recorded in co-contaminated soil planted with D. reflexa and amended with soy cake (75%), followed by potato skin (52.8%) and tea leaves (50.6%). Although plants did not accumulate hydrocarbon from the contaminated soil, significant bioaccumulation of lead in the roots and stems of D. reflexa was observed. At the end of 180 days, 16.7 and 9.8 mg kg(-1) of lead in the stems and roots of D. reflexa were recorded, respectively, for the treatment with tea leaves. These findings demonstrate the potential of organic waste amendments in enhancing phytoremediation of oil and bioaccumulation of lead.

  19. The potential for solubilizing agents to enhance the remediation of hydrophobic organic solutes in soil-water suspensions. [Quarterly report

    SciTech Connect

    Laha, S.; Liu, Z.; Edwards, D.; Luthy, R.G.

    1991-02-01

    This paper discusses the feasibility for use of surfactant solubilizing agents to enhance the solubility and the rate of microbial degradation of hydrophobic organic solutes in soil-water suspensions. Hydrophobic organic contaminants are strongly sorbed to soil or sediment material, and as a consequence the rate of microbial degradation may depend greatly on the desorption of the sorbed-phase contaminant and the accessibility of the contaminant to soil microorganisms. Chemical solubilizing agents may enhance the rate of hydrophobic organic solute degradation by increasing the rate of solute desorption from soil and the extent of solute partitioning to the aqueous phase. The presentation will review on-going research on: surfactant solubilization of polycyclic aromatic hydrocarbon (PAH) compounds in clean water, and in soil-water suspensions; and experiments to assess if the addition of surfactant to soil-water suspension results in faster rate of mineralization of PAH compounds in soil.

  20. The potential for solubilizing agents to enhance the remediation of hydrophobic organic solutes in soil-water suspensions

    SciTech Connect

    Laha, S.; Liu, Z.; Edwards, D.; Luthy, R.G.

    1991-02-01

    This paper discusses the feasibility for use of surfactant solubilizing agents to enhance the solubility and the rate of microbial degradation of hydrophobic organic solutes in soil-water suspensions. Hydrophobic organic contaminants are strongly sorbed to soil or sediment material, and as a consequence the rate of microbial degradation may depend greatly on the desorption of the sorbed-phase contaminant and the accessibility of the contaminant to soil microorganisms. Chemical solubilizing agents may enhance the rate of hydrophobic organic solute degradation by increasing the rate of solute desorption from soil and the extent of solute partitioning to the aqueous phase. The presentation will review on-going research on: surfactant solubilization of polycyclic aromatic hydrocarbon (PAH) compounds in clean water, and in soil-water suspensions; and experiments to assess if the addition of surfactant to soil-water suspension results in faster rate of mineralization of PAH compounds in soil.

  1. Remediation of a hexachlorobenzene-contaminated soil by surfactant-enhanced electrokinetics coupled with microscale Pd/Fe PRB.

    PubMed

    Wan, Jinzhong; Li, Zhirong; Lu, Xiaohua; Yuan, Songhu

    2010-12-15

    Treatment of soils contaminated with chlorinated hydrophobic organic compounds (CHOCs) remains a challenge for environmental scientists worldwide. In this study surfactant-enhanced electrokinetics (SEEK) was coupled with permeable reactive barrier (PRB) composed of microscale Pd/Fe to treat a hexachlorobenzene (HCB)-contaminated soil. A nonionic surfactant, Triton X-100 (TX-100), was selected as the solubility-enhancing agent. Five bench-scale tests were conducted to investigate the performance of EK-PRB on HCB removal from soils. Results showed that the HCB removal was generally increased by a factor of 4 by EK coupled with PRB compared with EK alone (60% versus 13%). In the EK-PRB system, HCB was removed from soil through several sequential processes: the movement driven by electroosmotic flow (EOF) in the anode column, the complete adsorption/degradation by the reactive Pd/Fe particles in PRB, and the consequent movement by EOF and probable electrochemical reactions in the cathode column. TX-100 was supposed to be a superior enhancement agent for HCB removal, not only in the EOF movement process but also in the Pd/Fe degradation process. This study indicates that the combination of SEEK and Pd/Fe PRB is efficient and promising to remove CHOCs from contaminated soils.

  2. Microbial functional diversity enhances predictive models linking environmental parameters to ecosystem properties.

    PubMed

    Powell, Jeff R; Welsh, Allana; Hallin, Sara

    2015-07-01

    Microorganisms drive biogeochemical processes, but linking these processes to real changes in microbial communities under field conditions is not trivial. Here, we present a model-based approach to estimate independent contributions of microbial community shifts to ecosystem properties. The approach was tested empirically, using denitrification potential as our model process, in a spatial survey of arable land encompassing a range of edaphic conditions and two agricultural production systems. Soil nitrate was the most important single predictor of denitrification potential (the change in Akaike's information criterion, corrected for sample size, ΔAIC(c) = 20.29); however, the inclusion of biotic variables (particularly the evenness and size of denitrifier communities [ΔAIC(c) = 12.02], and the abundance of one denitrifier genotype [ΔAIC(c) = 18.04]) had a substantial effect on model precision, comparable to the inclusion of abiotic variables (biotic R2 = 0.28, abiotic R2 = 0.50, biotic + abiotic R2 = 0.76). This approach provides a valuable tool for explicitly linking microbial communities to ecosystem functioning. By making this link, we have demonstrated that including aspects of microbial community structure and diversity in biogeochemical models can improve predictions of nutrient cycling in ecosystems and enhance our understanding of ecosystem functionality.

  3. Adolescent Literacy: More than Remediation

    ERIC Educational Resources Information Center

    Biancarosa, Gina

    2012-01-01

    The challenge of adolescent literacy involves more than providing remediation for students who have not mastered basic reading skills. To become successful learners, adolescents must master complex texts, understand the diverse literacy demands of the different content areas, and navigate digital texts. In this article, Biancarosa reviews what the…

  4. Crop rotational diversity enhances belowground communities and functions in an agroecosystem.

    PubMed

    Tiemann, L K; Grandy, A S; Atkinson, E E; Marin-Spiotta, E; McDaniel, M D

    2015-08-01

    Biodiversity loss, an important consequence of agricultural intensification, can lead to reductions in agroecosystem functions and services. Increasing crop diversity through rotation may alleviate these negative consequences by restoring positive aboveground-belowground interactions. Positive impacts of aboveground biodiversity on belowground communities and processes have primarily been observed in natural systems. Here, we test for the effects of increased diversity in an agroecosystem, where plant diversity is increased over time through crop rotation. As crop diversity increased from one to five species, distinct soil microbial communities were related to increases in soil aggregation, organic carbon, total nitrogen, microbial activity and decreases in the carbon-to-nitrogen acquiring enzyme activity ratio. This study indicates positive biodiversity-function relationships in agroecosystems, driven by interactions between rotational and microbial diversity. By increasing the quantity, quality and chemical diversity of residues, high diversity rotations can sustain soil biological communities, with positive effects on soil organic matter and soil fertility.

  5. Crop rotational diversity enhances belowground communities and functions in an agroecosystem.

    PubMed

    Tiemann, L K; Grandy, A S; Atkinson, E E; Marin-Spiotta, E; McDaniel, M D

    2015-08-01

    Biodiversity loss, an important consequence of agricultural intensification, can lead to reductions in agroecosystem functions and services. Increasing crop diversity through rotation may alleviate these negative consequences by restoring positive aboveground-belowground interactions. Positive impacts of aboveground biodiversity on belowground communities and processes have primarily been observed in natural systems. Here, we test for the effects of increased diversity in an agroecosystem, where plant diversity is increased over time through crop rotation. As crop diversity increased from one to five species, distinct soil microbial communities were related to increases in soil aggregation, organic carbon, total nitrogen, microbial activity and decreases in the carbon-to-nitrogen acquiring enzyme activity ratio. This study indicates positive biodiversity-function relationships in agroecosystems, driven by interactions between rotational and microbial diversity. By increasing the quantity, quality and chemical diversity of residues, high diversity rotations can sustain soil biological communities, with positive effects on soil organic matter and soil fertility. PMID:26011743

  6. Lead-resistant strain KQBT-3 inoculants of Tricholoma lobayensis Heim that enhance remediation of lead-contaminated soil.

    PubMed

    Li, Ying; Qin, Chui-Xin; Gao, Biyu; Hu, Yuanjia; Xu, Heng

    2015-01-01

    To enhance lead-detoxifying efficiency of Tricholoma lobayensis Heim, one lead-resistant strain KQBT-3 (Bacillus thuringiensis) was applied owing to its excellent ability to tolerate Pb. KQBT-3 domesticated in liquid medium with increasing lead concentrations could tolerate Pb(NO3)2 up to a concentration of 800 mg L(-1). Pot experiments showed that the KQBT-3 not only could promote the growth of T. lobayensis, but also could enhance its Pb accumulation ability under heavy metal stress. Biomass and accumulation of Pb increased 47.3% and 33.2%, respectively. In addition, after inoculation of KQBT-3, the significant decrease of malondialdehyde indicated KQBT-3 could alleviate lipid peroxidation in T. lobayensis. What is interesting is that superoxide dismutase and peroxidase activities in T. lobayensis inoculated with KQBT-3 were increased, and the maximum increasing rate was 121.71% and 117.29%, respectively. However, the catalase activity increased slightly. This revealed that inoculating KQBT-3 further induced oxidative response in T. lobayensis due to Pb accumulation. Therefore, the present work showed that KQBT-3 made a major contribution to promote growth and lead uptake of T. lobayensis and alleviate the oxidative stress. This kind of auxiliary effect on macrofungi can be developed into a novel bioremediation strategy.

  7. A context based approach using Green Chemistry/Bio-remediation principles to enhance interest and learning of organic chemistry in a high school AP chemistry classroom

    NASA Astrophysics Data System (ADS)

    Miller, Tricia

    The ability of our planet to sustain life and heal itself is not as predictable as it used to be. Our need for educated future scientists who know what our planet needs, and can passionately apply that knowledge to find solutions should be at the heart of science education today. This study of learning organic chemistry through the lens of the environmental problem "What should be done with our food scraps?" explores student interest, and mastery of certain concepts in organic chemistry. This Green Chemistry/ Bio-remediation context-based teaching approach utilizes the Nature MillRTM, which is an indoor food waste composting machine, to learn about organic chemistry, and how this relates to landfill reduction possibilities, and resource production. During this unit students collected food waste from their cafeteria, and used the Nature MillRTM to convert food waste into compost. The use of these hands on activities, and group discussions in a context-based environment enhanced their interest in organic chemistry, and paper chromatography. According to a one-tailed paired T-test, the result show that this context-based approach is a significant way to increase both student interest and mastery of the content.

  8. Application of biosurfactants and periodic voltage gradient for enhanced electrokinetic remediation of metals and PAHs in dredged marine sediments.

    PubMed

    Ammami, M T; Portet-Koltalo, F; Benamar, A; Duclairoir-Poc, C; Wang, H; Le Derf, F

    2015-04-01

    Dredged harbor sediment co-contaminated by heavy metals and polycyclic aromatic hydrocarbons (PAHs) was subjected to enhanced electrokinetic treatments, using a mixture of a chelating agent (citric acid CA) and a surfactant as additives in the processing fluids. We tested various operating conditions (at 1 V cm(-1)): different CA concentrations, applying a periodic voltage gradient, pre-conditioning the sediment with the additives, and replacing the synthetic surfactant Tween 20 (TW20) by biosurfactants. Increasing the CA concentration was favorable for both metal and PAH removal. Applying a periodic voltage gradient associated to a low concentration of CA and TW20 provided the best results for Zn, Cd and Pb removal and also for removal of the 16 priority PAHs. Promising results were obtained with solutions containing rhamnolipids (0.028%) and a viscosin-like biosurfactant produced by Pseudomonas fluorescens Pfa7B (0.025%), associated to a periodic voltage gradient. Although the rhamnolipid and the viscosin-like compounds involved a higher electrical current than TW20, metals were less removed from the sediment. The electroosmotic flow was lower when we used biosurfactants, hence a less effective effect on PAH removal.

  9. Enhanced Solubilisation of Six PAHs by Three Synthetic Cyclodextrins for Remediation Applications: Molecular Modelling of the Inclusion Complexes

    PubMed Central

    Morillo, Esmeralda; Sánchez-Trujillo, María Antonia; Moyano, José Ramón; Villaverde, Jaime; Gómez-Pantoja, María Eulalia; Pérez-Martínez, José Ignacio

    2012-01-01

    Solubilisation of six polycyclic aromatic hydrocarbons (PAHs) (acenaphthene, anthracene, fluoranthene, fluorene, phenanthrene and pyrene) by three synthetic cyclodextrins (CDs) (2-hydroxypropyl-β-CD, hydroxypropyl-γ-CD and ramdomly methylated-β-CD) was investigated in order to select the CD which presents the greatest increase in solubility and better complexation parameters for its use in contaminated scenarios. The presence of the three cyclodextrins greatly enhanced the apparent water solubility of all the PAHs through the formation of inclusion complexes of 1∶1 stoichiometry. Anthracene, fluoranthene, fluorene and phenanthrene clearly presented a higher solubility when β-CD derivatives were used, and especially the complexes with the ramdomly methylated-β-CD were favoured. On the contrary, pyrene presented its best solubility results when using 2-hydroxypropyl-γ-CD, but for acenaphthene the use of any of the three CDs gave the same results. Complementary to experimental phase-solubility studies, a more in-depth estimation of the inclusion process for the different complexes was carried out using molecular modelling in order to find a correlation between the degree of solubilisation and the fit of PAH molecules within the cavity of the different CDs and to know the predominant driving forces of the complexation. PMID:23028493

  10. Application of biosurfactants and periodic voltage gradient for enhanced electrokinetic remediation of metals and PAHs in dredged marine sediments.

    PubMed

    Ammami, M T; Portet-Koltalo, F; Benamar, A; Duclairoir-Poc, C; Wang, H; Le Derf, F

    2015-04-01

    Dredged harbor sediment co-contaminated by heavy metals and polycyclic aromatic hydrocarbons (PAHs) was subjected to enhanced electrokinetic treatments, using a mixture of a chelating agent (citric acid CA) and a surfactant as additives in the processing fluids. We tested various operating conditions (at 1 V cm(-1)): different CA concentrations, applying a periodic voltage gradient, pre-conditioning the sediment with the additives, and replacing the synthetic surfactant Tween 20 (TW20) by biosurfactants. Increasing the CA concentration was favorable for both metal and PAH removal. Applying a periodic voltage gradient associated to a low concentration of CA and TW20 provided the best results for Zn, Cd and Pb removal and also for removal of the 16 priority PAHs. Promising results were obtained with solutions containing rhamnolipids (0.028%) and a viscosin-like biosurfactant produced by Pseudomonas fluorescens Pfa7B (0.025%), associated to a periodic voltage gradient. Although the rhamnolipid and the viscosin-like compounds involved a higher electrical current than TW20, metals were less removed from the sediment. The electroosmotic flow was lower when we used biosurfactants, hence a less effective effect on PAH removal. PMID:25644703

  11. Increasing zooplankton size diversity enhances the strength of top-down control on phytoplankton in the East China Sea

    NASA Astrophysics Data System (ADS)

    Ye, L.; Chang, C.; García-Comas, C.; Gong, G.; Hsieh, C.

    2012-12-01

    Body size is one of the fundamental characteristics of organisms linking many ecosystem properties and functions. Recent studies suggest that environmental changes alter the size structure of pelagic food webs; however, ecosystem consequences of such changes remain unclear. Here we tested our main hypothesis that increasing zooplankton size diversity enhances top-down control on phytoplankton in the East China Sea (H1), as well as five conventional hypotheses explaining the top-down control: shallower zooplankton size spectrum enhances the strength of top-down control (H2); nutrient enrichment lessens the strength of top-down control (H3); increasing zooplankton taxonomic diversity enhances the strength of top-down control (H4); increasing fish predation is linked to decreasing the strength of top-down control of zooplankton on phytoplankton (H5); increasing temperature intensifies the strength of top-down control (H6). While the results of our univariate analyses support H1, H2, H3, and H4, more in depth analyses indicate that zooplankton size diversity is the most important factor in determining the strength of top-down control on phytoplankton in East China Sea. Our results suggest a new potential mechanism that increasing predator size diversity enhances the strength of top-down control on prey through diet niche partitioning. This mechanism can be explained by the concept of optimal predator-prey body-mass ratio concept. Suppose each size group of zooplankton predators has its own optimal phytoplankton prey size, increasing size diversity of zooplankton would promote diet niche partitioning of predators and thus elevates the top-down control.Fig. 1 Scatter plots the relationship between zooplankton/phytoplankton biomass ratio versus (A) zooplankton size diversity, (B) slope of zooplankton size spectrum, (C) Zoolankton Shannon diversity, (D) NO3, (E) PO4, (F) SiO3, (G) water temperature, and (H) fish larvae density in the East China Sea. Table 1. Results of the

  12. Wrinkle Remedies

    MedlinePlus

    ... Master Dermatologist Award Members Making a Difference Award Native American Health Service Resident Rotation PICMED Grant Professionalism Award ... Camp Discovery Diversity Mentorship Program Health Volunteers ... American Health Services Resident Rotation Resident International Grant Shade ...

  13. Scientist Spotlight Homework Assignments Shift Students' Stereotypes of Scientists and Enhance Science Identity in a Diverse Introductory Science Class.

    PubMed

    Schinske, Jeffrey N; Perkins, Heather; Snyder, Amanda; Wyer, Mary

    2016-01-01

    Research into science identity, stereotype threat, and possible selves suggests a lack of diverse representations of scientists could impede traditionally underserved students from persisting and succeeding in science. We evaluated a series of metacognitive homework assignments ("Scientist Spotlights") that featured counterstereotypical examples of scientists in an introductory biology class at a diverse community college. Scientist Spotlights additionally served as tools for content coverage, as scientists were selected to match topics covered each week. We analyzed beginning- and end-of-course essays completed by students during each of five courses with Scientist Spotlights and two courses with equivalent homework assignments that lacked connections to the stories of diverse scientists. Students completing Scientist Spotlights shifted toward counterstereotypical descriptions of scientists and conveyed an enhanced ability to personally relate to scientists following the intervention. Longitudinal data suggested these shifts were maintained 6 months after the completion of the course. Analyses further uncovered correlations between these shifts, interest in science, and course grades. As Scientist Spotlights require very little class time and complement existing curricula, they represent a promising tool for enhancing science identity, shifting stereotypes, and connecting content to issues of equity and diversity in a broad range of STEM classrooms.

  14. Scientist Spotlight Homework Assignments Shift Students' Stereotypes of Scientists and Enhance Science Identity in a Diverse Introductory Science Class.

    PubMed

    Schinske, Jeffrey N; Perkins, Heather; Snyder, Amanda; Wyer, Mary

    2016-01-01

    Research into science identity, stereotype threat, and possible selves suggests a lack of diverse representations of scientists could impede traditionally underserved students from persisting and succeeding in science. We evaluated a series of metacognitive homework assignments ("Scientist Spotlights") that featured counterstereotypical examples of scientists in an introductory biology class at a diverse community college. Scientist Spotlights additionally served as tools for content coverage, as scientists were selected to match topics covered each week. We analyzed beginning- and end-of-course essays completed by students during each of five courses with Scientist Spotlights and two courses with equivalent homework assignments that lacked connections to the stories of diverse scientists. Students completing Scientist Spotlights shifted toward counterstereotypical descriptions of scientists and conveyed an enhanced ability to personally relate to scientists following the intervention. Longitudinal data suggested these shifts were maintained 6 months after the completion of the course. Analyses further uncovered correlations between these shifts, interest in science, and course grades. As Scientist Spotlights require very little class time and complement existing curricula, they represent a promising tool for enhancing science identity, shifting stereotypes, and connecting content to issues of equity and diversity in a broad range of STEM classrooms. PMID:27587856

  15. Scientist Spotlight Homework Assignments Shift Students’ Stereotypes of Scientists and Enhance Science Identity in a Diverse Introductory Science Class

    PubMed Central

    Schinske, Jeffrey N.; Perkins, Heather; Snyder, Amanda; Wyer, Mary

    2016-01-01

    Research into science identity, stereotype threat, and possible selves suggests a lack of diverse representations of scientists could impede traditionally underserved students from persisting and succeeding in science. We evaluated a series of metacognitive homework assignments (“Scientist Spotlights”) that featured counterstereotypical examples of scientists in an introductory biology class at a diverse community college. Scientist Spotlights additionally served as tools for content coverage, as scientists were selected to match topics covered each week. We analyzed beginning- and end-of-course essays completed by students during each of five courses with Scientist Spotlights and two courses with equivalent homework assignments that lacked connections to the stories of diverse scientists. Students completing Scientist Spotlights shifted toward counterstereotypical descriptions of scientists and conveyed an enhanced ability to personally relate to scientists following the intervention. Longitudinal data suggested these shifts were maintained 6 months after the completion of the course. Analyses further uncovered correlations between these shifts, interest in science, and course grades. As Scientist Spotlights require very little class time and complement existing curricula, they represent a promising tool for enhancing science identity, shifting stereotypes, and connecting content to issues of equity and diversity in a broad range of STEM classrooms. PMID:27587856

  16. Earth Science Pipeline: Enhancing Diversity in the Geosciences Through Outreach and Research

    NASA Astrophysics Data System (ADS)

    McGill, S. F.; Fryxell, J. E.; Smith, A. L.; Leatham, W. B.; Brunkhorst, B. J.

    2004-12-01

    (GPS) to monitor elastic strain accumulation across the San Andreas and San Jacinto faults along a 70-km-long transect near our campus. To date 80 participants have been involved in the GPS project, including 23 undergraduate students from under-represented ethnic groups and 23 teachers. Several participants have remained involved in the project, helping to process and model the GPS data, leading to presentations at SCEC and AGU meetings. In addition, all of our data has been submitted to the Southern California Earthquake Center's Data Center and is available for use by other scientists. Of the participants in the GPS project, 100% would recommend the program to other students or teachers, 93% regarded the experience as very worthwhile, and 81% said that the project had greatly increased their interest in the Earth Sciences. It is still too early to measure the long-term fruit of our work with middle and early high school students. However, our work with undergraduate students is already beginning to show some promise. During the four years prior to the start of our efforts, the average number of geology majors from under-represented groups in our department was 5 (22.7% of the total number of geology majors). During the three years of focused effort, the average was 8.3 students from under-represented groups (28.4% of the total). This work was funded by a grant from the National Science Foundation's program Opportunities for Enhancing Diversity in the Geosciences.

  17. REPORT ON THE GEOELECTRICAL DETECTION OF SURFACTANT ENHANCED AQUIFER REMEDIATION OF PCE: PROPERTY CHANGES IN AQUEOUS SOLUTIONS DUE TO SURFACTANT TREATMENT OF PERCHLOROETHYLENE: IMPLICATIONS TO GEOPHYSICAL MEASUREMENTS

    EPA Science Inventory

    Select physicochemical properties of nine surfactants which are conventionally used in the remediation of perchloroethylene (PCE, a.k.a. tetrachloroethene) were evaluated with varying concentrations of PCE and indicator dyes in aqueous solutions using a response surface quadrati...

  18. Promotion of Mn(II) Oxidation and Remediation of Coal Mine Drainage in Passive Treatment Systems by Diverse Fungal and Bacterial Communities ▿ †

    PubMed Central

    Santelli, Cara M.; Pfister, Donald H.; Lazarus, Dana; Sun, Lu; Burgos, William D.; Hansel, Colleen M.

    2010-01-01

    Biologically active, passive treatment systems are commonly employed for removing high concentrations of dissolved Mn(II) from coal mine drainage (CMD). Studies of microbial communities contributing to Mn attenuation through the oxidation of Mn(II) to sparingly soluble Mn(III/IV) oxide minerals, however, have been sparse to date. This study reveals a diverse community of Mn(II)-oxidizing fungi and bacteria existing in several CMD treatment systems. PMID:20495049

  19. Enhancing Diversity in Computational Geoscience: An Essential Component of Our Response to a Changing Planet

    NASA Astrophysics Data System (ADS)

    Loft, R.

    2014-12-01

    Many of the best jobs and innovations in the 21st century will come from the information technology sector, and one of the greatest challenges and opportunities for humanity will be using this technology to better understand our environment and our impact on it. Yet in an increasingly diverse America, many elements of our society go missing in this critical intersection of opportunity and societal benefit. In this talk I will give an overview of our attempts to bring about a transformation of the Computational and Information System Laboratory (CISL) at the National Center for Atmospheric Research (NCAR) into a more inclusive and diverse organization, and to bring students from diverse backgrounds into contact with the grand change of understanding and living with a changing planet. In this context, the integration of specific programs like research internships, visitor support and diversity outreach will be discussed.

  20. Managing diversity and enhancing team outcomes: the promise of transformational leadership.

    PubMed

    Kearney, Eric; Gebert, Diether

    2009-01-01

    In a sample of 62 research and development (R&D) teams, the authors examined transformational leadership as a moderator of the relationship of age, nationality, and educational background diversity with team outcomes. When levels of transformational leadership were high, nationality and educational diversity were positively related to team leaders' longitudinal ratings of team performance. These relationships were nonsignificant when transformational leadership was low. Age diversity was not related to team performance when transformational leadership was high, and it was negatively related to team performance when transformational leadership was low. Two mediated moderation effects help explain these findings. Transformational leadership moderated the relationship of the 3 examined diversity dimensions with the elaboration of task-relevant information, which in turn was positively associated with team performance. Moreover, transformational leadership moderated the relationship of the 3 diversity types with collective team identification, which in turn was positively related to the elaboration of task-relevant information. The authors discuss the theoretical and practical implications of these results. Overall, this study suggests that transformational leadership can foster the utilization of the potential, but frequently untapped, benefits entailed by both demographic and informational/cognitive team diversity. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

  1. Enhanced interannual precipitation variability increases plant functional diversity that in turn ameliorates negative impact on productivity.

    PubMed

    Gherardi, Laureano A; Sala, Osvaldo E

    2015-12-01

    Although precipitation interannual variability is projected to increase due to climate change, effects of changes in precipitation variance have received considerable less attention than effects of changes in the mean state of climate. Interannual precipitation variability effects on functional diversity and its consequences for ecosystem functioning are assessed here using a 6-year rainfall manipulation experiment. Five precipitation treatments were switched annually resulting in increased levels of precipitation variability while maintaining average precipitation constant. Functional diversity showed a positive response to increased variability due to increased evenness. Dominant grasses decreased and rare plant functional types increased in abundance because grasses showed a hump-shaped response to precipitation with a maximum around modal precipitation, whereas rare species peaked at high precipitation values. Increased functional diversity ameliorated negative effects of precipitation variability on primary production. Rare species buffered the effect of precipitation variability on the variability in total productivity because their variance decreases with increasing precipitation variance. PMID:26437913

  2. Enhanced interannual precipitation variability increases plant functional diversity that in turn ameliorates negative impact on productivity.

    PubMed

    Gherardi, Laureano A; Sala, Osvaldo E

    2015-12-01

    Although precipitation interannual variability is projected to increase due to climate change, effects of changes in precipitation variance have received considerable less attention than effects of changes in the mean state of climate. Interannual precipitation variability effects on functional diversity and its consequences for ecosystem functioning are assessed here using a 6-year rainfall manipulation experiment. Five precipitation treatments were switched annually resulting in increased levels of precipitation variability while maintaining average precipitation constant. Functional diversity showed a positive response to increased variability due to increased evenness. Dominant grasses decreased and rare plant functional types increased in abundance because grasses showed a hump-shaped response to precipitation with a maximum around modal precipitation, whereas rare species peaked at high precipitation values. Increased functional diversity ameliorated negative effects of precipitation variability on primary production. Rare species buffered the effect of precipitation variability on the variability in total productivity because their variance decreases with increasing precipitation variance.

  3. Use of Borehole-Radar Methods to Monitor a Steam-Enhanced Remediation Pilot Study at a Quarry at the Former Loring Air Force Base, Maine

    USGS Publications Warehouse

    Gregoire, Colette; Joesten, Peter K.; Lane, Jr., John W.

    2007-01-01

    Single-hole radar reflection and crosshole radar tomography surveys were used in conjunction with conventional borehole-geophysical methods to evaluate the effectiveness of borehole-radar methods for monitoring the movement of steam and heat through fractured bedrock. The U.S. Geological Survey, in cooperation with U.S. Environmental Protection Agency (USEPA), conducted surveys in an abandoned limestone quarry at the former Loring Air Force Base during a field-scale, steam-enhanced remediation (SER) pilot project conducted by the USEPA, the U.S. Air Force, and the Maine Department of Environmental Protection to study the viability of SER to remediate non-aqueous phase liquid contamination in fractured bedrock. Numerical modeling and field experiments indicate that borehole-radar methods have the potential to monitor the presence of steam and to measure large temperature changes in the limestone matrix during SER operations. Based on modeling results, the replacement of water by steam in fractures should produce a decrease in radar reflectivity (amplitude of the reflected wave) by a factor of 10 and a change in reflection polarity. In addition, heating the limestone matrix should increase the bulk electrical conductivity and decrease the bulk dielectric permittivity. These changes result in an increase in radar attenuation and an increase in radar-wave propagation velocity, respectively. Single-hole radar reflection and crosshole radar tomography data were collected in two boreholes using 100-megahertz antennas before the start of steam injection, about 10 days after the steam injection began, and 2 months later, near the end of the injection. Fluid temperature logs show that the temperature of the fluid in the boreholes increased by 10?C (degrees Celsius) in one borehole and 40?C in the other; maximum temperatures were measured near the bottom of the boreholes. The results of the numerical modeling were used to interpret the borehole-radar data. Analyses of the

  4. State Strategies To Address Diversity and Enhance Equity in Higher Education.

    ERIC Educational Resources Information Center

    Ratliff, Charles A.; Rawlings, Howard P.; Ards, Sheila; Sherman, Jane

    The three case studies in this report describe state-level efforts to address diversity and equity in postsecondary institutions in California, Maryland, and Washington. A preface provides some background on affirmative action programs, litigation history, and the roles of state coordinating agencies and institutional governing boards. The…

  5. No Child Misunderstood: Enhancing Early Childhood Teachers' Multicultural Responsiveness to the Social Competence of Diverse Children

    ERIC Educational Resources Information Center

    Han, Heejeong Sophia; Thomas, M. Shelley

    2010-01-01

    As a result of rapid demographic changes in our society, more children from diverse racial/cultural backgrounds join our early childhood classrooms. The majority of early childhood teachers, on the other hand, are middle-class and of European-decent. This paper provides early childhood teachers with both theoretical and practical understandings…

  6. Science Inquiry and Student Diversity: Enhanced Abilities and Continuing Difficulties after an Instructional Intervention

    ERIC Educational Resources Information Center

    Lee, Okhee; Buxton, Cory; Lewis, Scott; LeRoy, Kathryn

    2006-01-01

    This study examines elementary students' abilities to conduct science inquiry through their participation in an instructional intervention over a school year. The study involved 25 third and fourth grade students from six elementary schools representing diverse linguistic and cultural groups. Prior to and at the completion of the intervention, the…

  7. Use of borehole radar reflection logging to monitor steam-enhanced remediation in fractured limestone-results of numerical modelling and a field experiment

    USGS Publications Warehouse

    Gregoire, C.; Joesten, P.K.; Lane, J.W.

    2006-01-01

    Ground penetrating radar is an efficient geophysical method for the detection and location of fractures and fracture zones in electrically resistive rocks. In this study, the use of down-hole (borehole) radar reflection logs to monitor the injection of steam in fractured rocks was tested as part of a field-scale, steam-enhanced remediation pilot study conducted at a fractured limestone quarry contaminated with chlorinated hydrocarbons at the former Loring Air Force Base, Limestone, Maine, USA. In support of the pilot study, borehole radar reflection logs were collected three times (before, during, and near the end of steam injection) using broadband 100 MHz electric dipole antennas. Numerical modelling was performed to predict the effect of heating on radar-frequency electromagnetic (EM) wave velocity, attenuation, and fracture reflectivity. The modelling results indicate that EM wave velocity and attenuation change substantially if heating increases the electrical conductivity of the limestone matrix. Furthermore, the net effect of heat-induced variations in fracture-fluid dielectric properties on average medium velocity is insignificant because the expected total fracture porosity is low. In contrast, changes in fracture fluid electrical conductivity can have a significant effect on EM wave attenuation and fracture reflectivity. Total replacement of water by steam in a fracture decreases fracture reflectivity of a factor of 10 and induces a change in reflected wave polarity. Based on the numerical modelling results, a reflection amplitude analysis method was developed to delineate fractures where steam has displaced water. Radar reflection logs collected during the three acquisition periods were analysed in the frequency domain to determine if steam had replaced water in the fractures (after normalizing the logs to compensate for differences in antenna performance between logging runs). Analysis of the radar reflection logs from a borehole where the temperature

  8. Development and Implementation of a Workshop to Enhance the Effectiveness of Mentors Working with Diverse Mentees in HIV Research

    PubMed Central

    Fernandez, Alicia; Stoff, David M.; Narahari, Swathi; Blank, Michael; Fuchs, Jonathan; Evans, Clyde H.; Kahn, James S.; Johnson, Mallory O.

    2014-01-01

    Abstract A growing body of evidence highlights the importance of competent mentoring in academic research in the field of HIV, particularly for early stage investigators from diverse, underrepresented backgrounds. We describe the development and implementation of a 2-day intensive workshop to train mid-level and senior-level investigators conducting HIV-related clinical and translational research across multiple academic institutions on more effective mentoring, with an emphasis on techniques to foster mentees of diversity. The workshop was focused on training mentors in techniques designed to improve the effectiveness of the mentor–mentee relationship, and included didactic presentations, interactive discussions, and small-group problem-based learning activities. Mid-level or senior-level faculty involved or planning to be involved in significant mentorship activities related to HIV research were eligible. Surveys and formal actions plans allowed for workshop evaluation and laid the groundwork for subsequent workshops. Twenty-six faculty from 16 U.S.-based institutions participated, with good representation across discipline, gender, and race/ethnicity. The sessions were highly rated and discussions and evaluations revealed important barriers and facilitators to mentoring, challenges and solutions related to mentoring mentees from diverse backgrounds, and specific tools to enhance mentoring effectiveness. The Mentoring the Mentors training program for HIV researchers focusing on early career investigators of diversity was the first of its kind and was well attended, was rated highly, and provided guidance for improving the program in the future. This training program fills an important gap in the HIV researcher community and offers guidance for training mentors interested in diversity issues in settings outside of HIV. PMID:24735004

  9. Development and implementation of a workshop to enhance the effectiveness of mentors working with diverse mentees in HIV research.

    PubMed

    Gandhi, Monica; Fernandez, Alicia; Stoff, David M; Narahari, Swathi; Blank, Michael; Fuchs, Jonathan; Evans, Clyde H; Kahn, James S; Johnson, Mallory O

    2014-08-01

    Abstract A growing body of evidence highlights the importance of competent mentoring in academic research in the field of HIV, particularly for early stage investigators from diverse, underrepresented backgrounds. We describe the development and implementation of a 2-day intensive workshop to train mid-level and senior-level investigators conducting HIV-related clinical and translational research across multiple academic institutions on more effective mentoring, with an emphasis on techniques to foster mentees of diversity. The workshop was focused on training mentors in techniques designed to improve the effectiveness of the mentor-mentee relationship, and included didactic presentations, interactive discussions, and small-group problem-based learning activities. Mid-level or senior-level faculty involved or planning to be involved in significant mentorship activities related to HIV research were eligible. Surveys and formal actions plans allowed for workshop evaluation and laid the groundwork for subsequent workshops. Twenty-six faculty from 16 U.S.-based institutions participated, with good representation across discipline, gender, and race/ethnicity. The sessions were highly rated and discussions and evaluations revealed important barriers and facilitators to mentoring, challenges and solutions related to mentoring mentees from diverse backgrounds, and specific tools to enhance mentoring effectiveness. The Mentoring the Mentors training program for HIV researchers focusing on early career investigators of diversity was the first of its kind and was well attended, was rated highly, and provided guidance for improving the program in the future. This training program fills an important gap in the HIV researcher community and offers guidance for training mentors interested in diversity issues in settings outside of HIV.

  10. Plant diversity affects behavior of generalist root herbivores, reduces crop damage, and enhances crop yield.

    PubMed

    Staudacher, Karin; Schallhart, Nikolaus; Thalinger, Bettina; Wallinger, Corinna; Juen, Anita; Traugott, Michael

    2013-07-01

    Soil-dwelling pests inflict considerable economic damage in agriculture but are hard to control. A promising strategy to reduce pest pressure on crops is to increase the plant diversity in agroecosystems. This approach, however, demands a sound understanding of species' interactions, which is widely lacking for subterranean herbivore-plant systems. Here, we examine the effects of plant diversification on wireworms, the soil-dwelling larvae of click beetles that threaten crops worldwide. We conducted a field experiment employing plant diversification by adding either wheat or a mix of six associated plants (grasses, legumes, and forbs) between rows of maize to protect it from Agriotes wireworms. Wireworm feeding behavior, dispersal between crop and associated plants, as well as maize damage and yield were examined. The former was assessed combining molecular gut content and stable isotope analysis. The pests were strongly attracted by the associated plants in August, when the crop was most vulnerable, whereas in September, shortly before harvest, this effect occurred only in the plant mix. In maize monoculture, the larvae stayed in the principal crop throughout the season. Larval delta13C signatures revealed that maize feeding was reduced up to sevenfold in wireworms of the vegetationally diversified treatments compared to those of the maize monoculture. These findings were confirmed by molecular analysis, which additionally showed a dietary preference of wireworms for specific plants in the associated plant mix. Compared to the monoculture, maize damage was reduced by 38% and 55% in the wheat and plant mix treatment, which translated into a yield increase of 30% and 38%, respectively. The present findings demonstrate that increasing the plant diversity in agroecosystems provides an effective insurance against soil pests. The underlying mechanisms are the diversion of the pest from the principle crop and a changed feeding behavior. The deployment of diverse mixes of

  11. Roseopurpurins: Chemical Diversity Enhanced by Convergent Biosynthesis and Forward and Reverse Michael Additions.

    PubMed

    Shang, Zhuo; Khalil, Zeinab; Li, Li; Salim, Angela A; Quezada, Michelle; Kalansuriya, Pabasara; Capon, Robert J

    2016-09-01

    Cultures of the estuarine fungus Penicillium roseopurpureum (CMB-MF038) yielded a diverse array of polyketides, many of which were related via a highly convergent biosynthetic pathway. In addition to revising and assigning structures, and documenting chemical and biological properties, pro-drug cytotoxic properties were attributed to roseopurpurins H (10) and I (11) on the basis of in situ reverse Michael addition to a cytotoxic Michael acceptor (12). PMID:27537356

  12. Wild Herbivore Grazing Enhances Insect Diversity over Livestock Grazing in an African Grassland System

    PubMed Central

    Roets, Francois; Samways, Michael J.

    2016-01-01

    Southern Africa’s grassland biodiversity is threatened by habitat transformation such as commercial forestry. Ecological networks (ENs) have been instigated to alleviate the pressure of habitat transformation on local biodiversity. ENs are large scale webs of corridors and patches of natural vegetation criss-crossing production landscapes that can simulate conditions in protected areas (PAs). Many ENs have lost many native large mammal species, which have been replaced by domestic livestock to retain natural grazing dynamics, which could have an impact on the long-term value of ENs for insects. Here we compared dung beetle, butterfly and grasshopper diversity in ENs across a landscape mosaic of timber plantations, where 1) wild megaherbivores were maintained, 2) in ENs where these herbivores were replaced by livestock and, 3) in a nearby World Heritage PA which retained its natural complement of megaherbivores. Sites in the PA far from any plantation were similar in composition to those in the wild grazed EN. Presence of the wild grazers improved the alpha- and beta-diversity of all focal insect taxa when compared to domestic grazing. Furthermore, species composition shows significant differences between the two grazing systems indicating that an assemblage of native large mammals facilitates insect diversity conservation. We support the maintenance or introduction of large native mammals in ENs or similar conservation areas in production landscapes to simulate the ecological conditions and natural heterogeneity in nearby PAs. PMID:27783685

  13. Diversity of larger consumers enhances interference competition effects on smaller competitors.

    PubMed

    Nascimento, Francisco J A; Karlson, Agnes M L; Näslund, Johan; Elmgren, Ragnar

    2011-06-01

    Competition between large and small species for the same food is common in a number of ecosystems including aquatic ones. How diversity of larger consumers affects the access of smaller competitors to a limiting resource is not well understood. We tested experimentally how species richness (0-3 spp.) of benthic deposit-feeding macrofauna changes meiofaunal ostracods' incorporation of fresh organic matter from a stable-isotope-labeled cyanobacterial bloom, using fauna from the species-poor Baltic Sea. Presence of macrofauna mostly decreased meiofaunal incorporation of bloom material, depending on the macrofauna species present. As expected, the species identity of macrofauna influenced the incorporation of organic matter by meiofauna. Interestingly, our results show that, in addition, species richness of the macrofauna significantly reduced meiofauna incorporation of freshly settled nitrogen and carbon. With more than one macrofauna species, the reduction was always greater than expected from the single-species treatments. Field data from the Baltic Sea showed a negative correlation between macrofauna diversity and meiofaunal ostracod abundance, as expected from the experimental results. We argue that this is caused by interference competition, due to spatial niche differentiation between macrofauna species reducing the sediment volume in which ostracods can feed undisturbed by larger competitors. Interference from macrofauna significantly reduces organic matter incorporation by meiofauna, indicating that diversity of larger consumers is an important factor controlling the access of smaller competitors to a limiting food resource.

  14. Enhancing Orthographic Competencies and Reducing Domain-Specific Test Anxiety: The Systematic Use of Algorithmic and Self-Instructional Task Formats in Remedial Spelling Training

    ERIC Educational Resources Information Center

    Faber, Gunter

    2010-01-01

    In this study the effects of a remedial spelling training approach were evaluated, which systematically combines certain visualization and verbalization methods to foster students' spelling knowledge and strategy use. Several achievement and test anxiety data from three measurement times were analyzed. All students displayed severe spelling…

  15. Implementing sponge physiological and genomic information to enhance the diversity of its culturable associated bacteria.

    PubMed

    Lavy, Adi; Keren, Ray; Haber, Markus; Schwartz, Inbar; Ilan, Micha

    2014-02-01

    In recent years new approaches have emerged for culturing marine environmental bacteria. They include the use of novel culture media, sometimes with very low-nutrient content, and a variety of growth conditions such as temperature, oxygen levels, and different atmospheric pressures. These approaches have largely been neglected when it came to the cultivation of sponge-associated bacteria. Here, we used physiological and environmental conditions to reflect the environment of sponge-associated bacteria along with genomic data of the prominent sponge symbiont Candidatus Poribacteria sp. WGA-4E, to cultivate bacteria from the Red Sea sponge Theonella swinhoei. Designing culturing conditions to fit the metabolic needs of major bacterial taxa present in the sponge, through a combined use of diverse culture media compositions with aerobic and microaerophilic states, and addition of antibiotics, yielded higher diversity of the cultured bacteria and led to the isolation of novel sponge-associated and sponge-specific bacteria. In this work, 59 OTUs of six phyla were isolated. Of these, 22 have no close type strains at the species level (< 97% similarity of 16S rRNA gene sequence), representing novel bacteria species, and some are probably new genera and even families.

  16. Probabilistic modelling of chromatin code landscape reveals functional diversity of enhancer-like chromatin states

    PubMed Central

    Zhou, Jian; Troyanskaya, Olga G.

    2016-01-01

    Interpreting the functional state of chromatin from the combinatorial binding patterns of chromatin factors, that is, the chromatin codes, is crucial for decoding the epigenetic state of the cell. Here we present a systematic map of Drosophila chromatin states derived from data-driven probabilistic modelling of dependencies between chromatin factors. Our model not only recapitulates enhancer-like chromatin states as indicated by widely used enhancer marks but also divides these states into three functionally distinct groups, of which only one specific group possesses active enhancer activity. Moreover, we discover a strong association between one specific enhancer state and RNA Polymerase II pausing, linking transcription regulatory potential and chromatin organization. We also observe that with the exception of long-intron genes, chromatin state transition positions in transcriptionally active genes align with an absolute distance to their corresponding transcription start site, regardless of gene length. Using our method, we provide a resource that helps elucidate the functional and spatial organization of the chromatin code landscape. PMID:26841971

  17. Enhancing Behavioral Couple Therapy: Addressing the Therapeutic Alliance, Hope, and Diversity

    ERIC Educational Resources Information Center

    Kelly, Shalonda; Iwamasa, Gayle Y.

    2005-01-01

    The strengths and weaknesses of behavioral couple therapy (BCT) are well documented and disseminated, and this couple therapy approach continues to evolve. Newer behaviorally based approaches share an openness to integration and can enhance the ability of BCT to address three key process-related variables: the therapeutic alliance, hope, and…

  18. [What perspectives for cognitive remediation in schizophrenia?].

    PubMed

    Correard, N; Mazzola-Pomietto, P; Elissalde, S-N; Viglianese-Salmon, N; Fakra, E; Azorin, J-M

    2011-12-01

    Cognitive deficits are routinely evident in schizophrenia, and are of sufficient magnitude to influence functional outcomes in work, social functioning and illness management. Cognitive remediation is an evidenced-based non-pharmacological treatment for the neurocognitive deficits seen in schizophrenia. Narrowly defined, cognitive remediation is a set of cognitive drills or compensatory interventions designed to enhance cognitive functioning, but from the vantage of the psychiatric rehabilitation field, cognitive remediation is a therapy which engages the patient in learning activities that enhance the neurocognitive skills relevant to their chosen recovery goals. Cognitive remediation programs vary in the extent to which they reflect these narrow or broader perspectives but a metaanalytic study reports moderate range effect sizes on cognitive test performance, and daily functioning. Reciprocal interactions between baseline ability level, the type of instructional techniques used, and motivation provide some explanatory power for the heterogeneity in patient response to cognitive remediation. Recent studies indicate that intrinsic motivation mediates the relationship between neurocognition and functional outcomes. Results of these studies suggest that intrinsic motivation should be a viable treatment target in cognitive remediation intervention. In this perspective, NEAR (Neuropsychological Educational Approach to Remediation) program was created to enhance intrinsic motivation by employing more engaging and interesting software packages for cognitive practice, involving consumers in choosing the focus of training and having the NEAR leader serve as a coach to engage the consumers in active guidance of their own treatment program.

  19. Stabilisation of nanoscale zero-valent iron with biochar for enhanced transport and in-situ remediation of hexavalent chromium in soil.

    PubMed

    Su, Huijie; Fang, Zhanqiang; Tsang, Pokeung Eric; Fang, Jianzhang; Zhao, Dongye

    2016-07-01

    In this study, a biochar-supported nanoscale zero-valent iron (nZVI@BC) material was used for in situ remediation of hexavalent chromium-contaminated soil. Sedimentation tests and column experiments were used to compare the stability and mobility of nZVI@BC and bare-nZVI. The immobilisation efficiency of chromium, toxic effect of chromium and the content of iron were assessed through leaching tests and pot experiments. Sedimentation tests and transport experiments indicated that nZVI@BC with nZVI to BC mass ratio of 1:1 exhibited better stability and mobility than that of bare-nZVI. The immobilisation efficiency of Cr(VI) and Crtotal was 100% and 92.9%, respectively, when the soil was treated with 8 g/kg of nZVI@BC for 15 days. Moreover, such remediation effectively reduced the leachability of Fe caused by bare-nZVI. In addition, pot experiments showed that such remediation reduced the phytotoxicity of Cr and the leachable Fe and was favourable for plant growth. PMID:27064615

  20. A Ten-Year Retrospective Look at the NSF/GEO Opportunities for Enhancing Diversity in the Geosciences (OEDG) Program

    NASA Astrophysics Data System (ADS)

    Karsten, J. L.

    2013-12-01

    The Opportunities for Enhancing Diversity in the Geosciences (OEDG) program - established in 2002 by the National Science Foundation's Directorate for Geosciences (GEO) - has been a mainstay in GEO's efforts to broaden participation of traditionally underrepresented minorities in the geosciences. The primary goal of the OEDG program has been to engage a diverse population of students in learning about - and pursuing advanced degrees and careers in - the geosciences. Raising public awareness of the importance and relevance of the geosciences among diverse audiences has been a secondary goal. During the past decade, the OEDG program has supported a variety of planning grants, proof-of-concept projects, and larger full-scale implementation efforts across the U.S. These projects have contributed a rich array of culturally-tailored resources for learning about geoscience career pathways and opportunities to participate in geoscience research experiences. OEDG has also developed networking and mentoring programs tailored for diverse student audiences, as well as the educators who work with them, and has helped to build capacity in the geosciences at minority-serving institutions. Perhaps the most important legacy of the OEDG program has been the establishment of an enthusiastic and effective community of educators, administrators, students and organizations dedicated to increasing diversity in the geosciences. Evaluation data collected for individual OEDG projects has helped to improve the impact of specific projects and increase our understanding of which approaches are more successful in achieving OEDG program goals. In addition, GEO has supported a decade-long, program-wide evaluation of the OEDG portfolio through a contract to the American Institutes for Research (AIR). Synthesis of results from both the project- and program-level evaluation activities has identified evidence-based 'best practices' that are essential for achieving success in broadening participation

  1. DDE remediation and degradation.

    PubMed

    Thomas, John E; Ou, Li-Tse; All-Agely, Abid

    2008-01-01

    breakdown of DDE by the extracellular lignolytic enzymes produced by white rot fungi. The addition of adjutants such as sodium ion, surfactants, and cellulose increased the rate of DDT aerobic or anaerobic degradation but did little to enhance the rate of DDE disappearance under anaerobic conditions. Only in the past decade has it been demonstrated that DDE can undergo reductive dechlorination under methanogenic and sulfidogenic conditions to form the degradation product DDMU, 1-chloro-2,2'-bis-(4'-chlorophenyl)ethane. The only pure culture reported to degrade DDE under anaerobic conditions was the denitrifier Alcaligens denitrificans. The degradation of DDE by this bacterium was enhanced by glucose, whereas biphenyl fumes had no effect. Abiotic remediation by DDE volatilization was enhanced by flooding and irrigation and deepplowing inhibited the volatilization. The use of zero-valent iron and surfactants in flooded soils enhanced DDT degradation but did not significantly alter the rate of DDE removal. Other catalysts (palladized magnesium, palladium on carbon, and nickel/aluminum alloys) degraded DDT and its metabolites, including DDE. However, these systems are often biphasic or involve explosive gases or both. Safer abiotic alternatives use UV light with titanium oxide or visible light with methylene green to degrade DDT, DDD, and DDE in aqueous or mixed solvent systems. Remediation and degradation of DDE in soil and water by phytoextraction, aerobic and anaerobic microorganisms, or abiotic methods can be accomplished. However, success has been limited, and great care must be taken that the method does not transfer the contaminants to another locale (by volatilization, deep plowing, erosion, or runoff) or to another species (by ingestion of accumulating plants or contaminated water). Although the remediation of DDT-, DDD-, and DDE-contaminated soil and water is beset with myriad problems, there remain many open avenues of research. PMID:18069646

  2. A Call for Training the Trainers: Focus on Mentoring to Enhance Diversity in Mental Health Research

    PubMed Central

    Twamley, Elizabeth W.; Cardenas, Veronica; Lebowitz, Barry; Reynolds, Charles F.

    2009-01-01

    There is a widening disparity between the proportion of ethnic minority Americans in the population and the number of researchers from these minority groups. One major obstacle in this arena relates to a dearth of mentors for such trainees. The present academic settings are not optimal for development and sustenance of research mentors, especially for mentees from underrepresented minority ethnic groups. Mentoring skills can and should be evaluated and enhanced. Universities, medical schools, and funding agencies need to join hands and implement national- and local-level programs to help develop and reward mentors of junior scientists from ethnic minority groups. PMID:19246662

  3. Reinventing Remedial Education

    ERIC Educational Resources Information Center

    Stuart, Reginald

    2009-01-01

    Remedial education, although widely used and disguised with other names, was rarely talked about for it could tarnish a school's reputation if widely discussed. Today, more and more colleges and universities are ditching the old stigma associated with remedial education, reinventing their remedial education and retention programs and, in the…

  4. Enhancing attachment security in the infants of women in a jail-diversion program.

    PubMed

    Cassidy, Jude; Ziv, Yair; Stupica, Brandi; Sherman, Laura J; Butler, Heidi; Karfgin, Andrea; Cooper, Glen; Hoffman, Kent T; Powell, Bert

    2010-07-01

    Pregnant female offenders face multiple adversities that make successful parenting difficult. As a result, their children are at risk of developing insecure attachment and attachment disorganization, both of which are associated with an increased likelihood of poor developmental outcomes. We evaluated the outcomes of participants in Tamar's Children, a 15-month jail-diversion intervention for pregnant, nonviolent offenders with a history of substance abuse. All women received extensive wrap-around social services as well as the Circle of Security Perinatal Protocol (Cooper, Hoffman, & Powell, 2003). We present data on 20 women and their infants who completed the full dosage of treatment (a residential-living phase from pregnancy until infant age six months and community-living phase until 12 months). Results indicated that (1) program infants had rates of attachment security and attachment disorganization comparable to rates typically found in low-risk samples (and more favorable than those typically found in high-risk samples); (2) program mothers had levels of maternal sensitivity comparable to mothers in an existing community comparison group; and (3) improvement over time emerged for maternal depressive symptomatology, but not other aspects of maternal functioning. Given the lack of a randomized control group, results are discussed in terms of the exploratory, program-development nature of the study.

  5. A gonogenic stimulated transition of mouse embryonic stem cells with enhanced control of diverse differentiation pathways

    PubMed Central

    Moshfegh, Cameron; Aires, Lina; Kisielow, Malgorzata; Vogel, Viola

    2016-01-01

    Embryonic stem (ES) cells share markers with undifferentiated primordial germ cells (PGCs). Here, we discovered that a cellular state with some molecular markers of male gonocyte induction, including a G1/S phase arrest and upregulation of specific genes such as Nanos2, Tdrd1, Ddx4, Zbtb16 and Plk1s1, can be chemically induced in male mouse ES cells in vitro, which we termed gonogenic stimulated transition (GoST). After longer culture of the resulting GoST cells without chemical stimulation, several molecular markers typical for early gonocytes were detected including the early gonocyte marker Tex101. Motivated by previous studies that found multipotency in cell lines derived from neonatal male germ cells in vitro, we then compared the differentiation potential of GoST cells to that of ES cells in vitro. Interestingly, GoST cells showed equal neurogenic, but enhanced cardiogenic and hepatogenic differentiation compared to ES cells in vitro. This work shows for the first time that some important molecular markers of the first developmental sexual differentiation program can be induced in male mouse ES cells in vitro and defines a novel concept to generate cells with enhanced multipotency. PMID:27157261

  6. A gonogenic stimulated transition of mouse embryonic stem cells with enhanced control of diverse differentiation pathways.

    PubMed

    Moshfegh, Cameron; Aires, Lina; Kisielow, Malgorzata; Vogel, Viola

    2016-05-09

    Embryonic stem (ES) cells share markers with undifferentiated primordial germ cells (PGCs). Here, we discovered that a cellular state with some molecular markers of male gonocyte induction, including a G1/S phase arrest and upregulation of specific genes such as Nanos2, Tdrd1, Ddx4, Zbtb16 and Plk1s1, can be chemically induced in male mouse ES cells in vitro, which we termed gonogenic stimulated transition (GoST). After longer culture of the resulting GoST cells without chemical stimulation, several molecular markers typical for early gonocytes were detected including the early gonocyte marker Tex101. Motivated by previous studies that found multipotency in cell lines derived from neonatal male germ cells in vitro, we then compared the differentiation potential of GoST cells to that of ES cells in vitro. Interestingly, GoST cells showed equal neurogenic, but enhanced cardiogenic and hepatogenic differentiation compared to ES cells in vitro. This work shows for the first time that some important molecular markers of the first developmental sexual differentiation program can be induced in male mouse ES cells in vitro and defines a novel concept to generate cells with enhanced multipotency.

  7. Functional organization of an Mbp enhancer exposes striking transcriptional regulatory diversity within myelinating glia.

    PubMed

    Dionne, Nancy; Dib, Samar; Finsen, Bente; Denarier, Eric; Kuhlmann, Tanja; Drouin, Régen; Kokoeva, Maia; Hudson, Thomas J; Siminovitch, Kathy; Friedman, Hana C; Peterson, Alan C

    2016-01-01

    In mammals, large caliber axons are ensheathed by myelin, a glial specialization supporting axon integrity and conferring accelerated and energy-efficient action potential conduction. Myelin basic protein (MBP) is required for normal myelin elaboration with maximal mbp transcription in oligodendrocytes requiring the upstream M3 enhancer. To further characterize the mechanism regulating mbp transcription, we defined M3 structure/function relationships by evaluating its evolutionary conservation, DNA footprints and the developmental programing conferred in mice by M3 derivatives. Multiple M3 regulatory element combinations were found to drive expression in oligodendrocytes and Schwann cells with a minimal 129 bp sequence conferring expression in oligodendrocytes throughout myelin elaboration, maintenance and repair. Unexpectedly, M3 derivatives conferred markedly different spatial and temporal expression programs thus illuminating striking transcriptional heterogeneity within post-mitotic oligodendrocytes. Finally, one M3 derivative engaged only during primary myelination, not during adult remyelination, demonstrating that transcriptional regulation in the two states is not equivalent. PMID:26507463

  8. Can repeated fertilizer applications to young Norway spruce enhance avian diversity in intensively managed forests?

    PubMed

    Edenius, Lars; Mikusiński, Grzegorz; Bergh, Johan

    2011-07-01

    Repeated fertilization of forests to increase biomass production is an environmentally controversial proposal, the effects of which we assessed on breeding birds in stands of young Norway spruce (Picea abies), in an intensively managed forest area in southern Sweden. Our results show that fertilized stands had 38% more species and 21% more individuals than unfertilized stands. Compared with stands under traditional management, the further intensification of forestry by repeated applications of fertilizers thus seemed to enhance species richness and abundance of forest birds. We cannot conclude at this stage whether the response in the bird community was caused by changes in food resources or increased structural complexity in the forest canopy due to the skid roads used for the application of the fertilizers. Future studies should focus on structural and compositional effects of fertilization processes during the entire rotation period and at assessing its effects in a landscape PMID:21848140

  9. Duct Remediation Program: Remediation operations and implementation

    SciTech Connect

    Beckman, T.d.; Davis, M.M.; Karas, T.M.

    1992-11-01

    Plutonium holdup material has accumulated in the process ventilation duct systems at Rocky Flats. Non-Destructive Assay (NDA) measurements identified ducts containing this material. The Defense Nuclear Facility Safety Board and the Department of Energy established the criteria for remediation of these ducts. A remediation team was assembled and a program plan created. This program plan included activities such as fissile material accumulation identification, criticality safety assessments, radiation dose determinations, facility safety evaluations, prevention of future accumulation, and removal of holdup material. Several operational considerations had to be evaluated in determining completion of remediation.

  10. [Enhanced remediation of 4-chloronitrobenzene contaminated groundwater with nanoscale zero-valence iron (nZVI) catalyzed hydrogen peroxide (H2O2)].

    PubMed

    Fu, Rong-Bing

    2014-04-01

    Chemical oxidation-reduction technology is an important way to quickly remedy contaminated groundwater. Nanoscale zero-valent iron (nZVI) was produced by liquid-phase reduction using FeSO4 and NaBH4, and characterized by SEM and XRD. The remediation of 4-chloronitrobezene (4-CINB) contaminated groundwater at ambient temperature and pressure was conducted with the nZVI catalytic H2O2 process, and the affecting factors and degradation mechanisms were investigated. The results indicated that under initial pH 3.0 at the temperature of 30 degrees C, after 30 mins of reaction, 4-ClNB in groundwater was completely degraded when the concentrations of nZVI and H2O2 were 268.8 mg x L(-1) and 4.90 mmol x L(-1), respectively. 4-chloronitrosobenzene, 4-chlorophenylhydroxylamine, 4-chloroazoxybenzene, 4-chloroaniline, 4-chloroazobenzene, 4-benzoquinone, acetic acid, formic acid, oxalic acid and chlorine ion were identified as the major intermediates of 4-ClNB degradation after the process. A tentative pathway for the degradation of 4-ClNB was proposed.

  11. Does agricultural crop diversity enhance soil microbial biomass and organic matter dynamics? A meta-analysis.

    PubMed

    McDaniel, M D; Tiemann, L K; Grandy, A S

    2014-04-01

    Our increasing dependence on a small number of agricultural crops, such as corn, is leading to reductions in agricultural biodiversity. Reductions in the number of crops in rotation or the replacement of rotations by monocultures are responsible for this loss of biodiversity. The belowground implications of simplifying agricultural plant communities remain unresolved; however, agroecosystem sustainability will be severely compromised if reductions in biodiversity reduce soil C and N concentrations, alter microbial communities, and degrade soil ecosystem functions as reported in natural communities. We conducted a meta-analysis of 122 studies to examine crop rotation effects on total soil C and N concentrations, and the faster cycling microbial biomass C and N pools that play key roles in soil nutrient cycling and physical processes such as aggregate formation. We specifically examined how rotation crop type and management practices influence C and N dynamics in different climates and soil types. We found that adding one or more crops in rotation to a monoculture increased total soil C by 3.6% and total N by 5.3%, but when rotations included a cover crop (i.e., crops that are not harvested but produced to enrich the soil and capture inorganic N), total C increased by 8.5% and total N 12.8%. Rotations substantially increased the soil microbial biomass C (20.7%) and N (26.1%) pools, and these overwhelming effects on microbial biomass were not moderated by crop type or management practices. Crop rotations, especially those that include cover crops, sustain soil quality and productivity by enhancing soil C, N, and microbial biomass, making them a cornerstone for sustainable agroecosystems.

  12. Does agricultural crop diversity enhance soil microbial biomass and organic matter dynamics? A meta-analysis.

    PubMed

    McDaniel, M D; Tiemann, L K; Grandy, A S

    2014-04-01

    Our increasing dependence on a small number of agricultural crops, such as corn, is leading to reductions in agricultural biodiversity. Reductions in the number of crops in rotation or the replacement of rotations by monocultures are responsible for this loss of biodiversity. The belowground implications of simplifying agricultural plant communities remain unresolved; however, agroecosystem sustainability will be severely compromised if reductions in biodiversity reduce soil C and N concentrations, alter microbial communities, and degrade soil ecosystem functions as reported in natural communities. We conducted a meta-analysis of 122 studies to examine crop rotation effects on total soil C and N concentrations, and the faster cycling microbial biomass C and N pools that play key roles in soil nutrient cycling and physical processes such as aggregate formation. We specifically examined how rotation crop type and management practices influence C and N dynamics in different climates and soil types. We found that adding one or more crops in rotation to a monoculture increased total soil C by 3.6% and total N by 5.3%, but when rotations included a cover crop (i.e., crops that are not harvested but produced to enrich the soil and capture inorganic N), total C increased by 8.5% and total N 12.8%. Rotations substantially increased the soil microbial biomass C (20.7%) and N (26.1%) pools, and these overwhelming effects on microbial biomass were not moderated by crop type or management practices. Crop rotations, especially those that include cover crops, sustain soil quality and productivity by enhancing soil C, N, and microbial biomass, making them a cornerstone for sustainable agroecosystems. PMID:24834741

  13. Enhancing Ocean Literacy and Expertise of Diverse Populations via Graduate School Fellowship Opportunities

    NASA Astrophysics Data System (ADS)

    Mayo, M.; Ithier-Guzman, W.; Pyrtle, A. J.; Betzer, P.; Batson, B.; Bhansali, S.; Greene, B.; Turner, R.

    2007-05-01

    In 2004, the University of South Florida (USF) was granted by the National Science Foundation a Louis Stokes Alliance for Minority Participation (LSAMP) Bridge to the Doctorate (BD) site award (HRD# 0217675). As part of the Florida-Georgia Louis Stokes Alliance for Minority Participation (FGLSAMP), USF is one of thirteen institutions in an alliance that is dedicated to significantly increasing the number of underrepresented minority students who obtain undergraduate and graduate STEM degrees. The BD program at USF incorporates the goals of FGLSAMP and facilitates the recruitment of underrepresented minorities pursuing careers in the STEM fields at the graduate level. The thematic focus of the FGLSAMP USF BD program is focused on the development and application of biogeochemical sensors for marine, aquatic, environmental, remote sensing and biomedical applications. After recruitment, BD graduate fellowship recipients are provided with NSF-funded financial support for two years, and opportunities to participate in professional development workshops, seminars and short courses, as well as additional financial support to pursue and complete their doctoral studies (beyond the initial two years of NSF BD funding), in a variety of forms, including, but not limited to, Alfred P. Sloan Minority Scholarships, Florida Education Fund's McKnight Doctoral Fellowships, USF College of Graduate Studies Fellowships, USF CMS endowed fellowships, USF CMS research assistantships, and USF CMS teaching assistantships. Collectively, 3 LSAMP BD grants have been awarded at USF to support 56 underrepresented minority fellowship recipients, of which 14 are currently graduate students at the USF College of Marine Science (CMS). Since the arrival of the BD Fellowship program, the graduate community has diversified, showing an increase of over 40% in underrepresented minorities at CMS. The BD program has enhanced the research and learning environment for all CMS students, as well as fostered a

  14. Natural Remediation at Savannah River Site

    SciTech Connect

    Lewis, C. M.; Van Pelt, R.

    2002-02-25

    Natural remediation is a general term that includes any technology or strategy that takes advantage of natural processes to remediate a contaminated media to a condition that is protective of human health and the environment. Natural remediation techniques are often passive and minimally disruptive to the environment. They are generally implemented in conjunction with traditional remedial solutions for source control (i.e., capping, stabilization, removal, soil vapor extraction, etc.). Natural remediation techniques being employed at Savannah River Site (SRS) include enhanced bio-remediation, monitored natural attenuation, and phytoremediation. Enhanced bio-remediation involves making nutrients available and conditions favorable for microbial growth. With proper precautions and feeding, the naturally existing microbes flourish and consume the contaminants. Case studies of enhanced bio-remediation include surface soils contaminated with PCBs and pesticides, and Volatile Organic Compound (VOC) contamination in both the vadose zone and groundwater. Monitored natural attenuation (MNA) has been selected as the preferred alternative for groundwater clean up at several SRS waste units. Successful implementation of MNA has been based on demonstration that sources have been controlled, groundwater modeling that indicates that plumes will not expand or reach surface water discharge points at levels that exceed regulatory limits, and continued monitoring. Phytoremediation is being successfully utilized at several SRS waste units. Phytoremediation involves using plants and vegetation to uptake, break down, or manage contaminants in groundwater or soils. Case studies at SRS include managing groundwater plumes of tritium and VOCs with pine trees that are native to the area. Significant decreases in tritium discharge to a site stream have been realized in one phytoremediation project. Studies of other vegetation types, methods of application, and other target contaminants are

  15. Diversity of LTR-retrotransposons and Enhancer/Suppressor Mutator-like transposons in cassava (Manihot esculenta Crantz).

    PubMed

    Gbadegesin, Michael A; Wills, Matthew A; Beeching, John R

    2008-10-01

    Cassava (Manihot esculenta Crantz), though a major world crop with enormous potential, is very under studied. Little is known about its genome structure and organisation. Transposable elements have a key role in the evolution of genome structure, and can be used as important tools in applied genetics. This paper sets out to survey the diversity of members of three major classes of transposable element within the cassava genome and in relation to similar elements in other plants. Members of two classes of LTR-retrotransposons, Ty1/copia-like and Ty3/gypsy-like, and of Enhancer/Suppressor Mutator (En/Spm)-like transposons were isolated and characterised. Analyses revealed 59 families of Ty1/copia, 26 families of Ty3/gypsy retrotransposons, and 40 families of En/Spm in the cassava genome. In the comparative analyses, the predicted amino acid sequences for these transposon classes were compared with those of related elements from other plant species. These revealed that there were multiple lineages of Ty1/copia-like retrotransposons in the genome of cassava and suggested that vertical and horizontal transmission as the source of cassava Mecops may not be mutually exclusive. For the Ty3/gypsy elements network, two groups of cassava Megyps were evident including the Arabidopsis Athila lineage. However, cassava En/Spm-like elements (Meens) constituted a single group within a network of plant En/Spm-like elements. Hybridisation analysis supported the presence of transposons in the genome of cassava in medium (Ty3/gypsy and En/Spm) to high (Ty1/copia) copy numbers. Thus the cassava genome was shown to contain diverse members of three major classes of transposable element; however, the different classes exhibited contrasting evolutionary histories.

  16. Opportunities and challenges for enhancing preconception health in primary care: qualitative study with women from ethnically diverse communities

    PubMed Central

    Tuomainen, Helena; Cross-Bardell, Laura; Bhoday, Mandeep; Qureshi, Nadeem; Kai, Joe

    2013-01-01

    Objective  There is a growing interest in developing and offering more systematic preconception healthcare. However, it is unclear how this might be regarded by ethnically diverse communities at higher risk of poor maternal and child health outcomes. We sought to explore perceptions about preconception health and care among women from these communities to identify opportunities and challenges for intervention development in primary care. Design Qualitative study using focus groups and semistructured interviews. Setting Ethnically diverse and socially disadvantaged community settings of the UK. Participants 41 women aged 18–45 years, of Pakistani, Indian, Caribbean, African, White and mixed ethnic origin, participating in nine focus groups, half of whom (n=19) had one-to-one follow-up telephone interviews. Results Women had modest or poor awareness of preconception health issues. They perceived these could be addressed in primary care, particularly if raised within a range of clinically ‘relevant’ consultations, such as for contraception, or when opportune for individuals in their social context. However, challenges for engaging women in preconception care more routinely were underlined. These included little prevailing culture of preparing for pregnancy and the realities of their pregnancies often being unplanned; and, for those planning pregnancy, sensitivity and maintaining secrecy when trying to conceive. A preference for female professionals, engaging men, and enhancing access for younger people or women less disposed to general practice, in educational and other settings were highlighted. Conclusions Raising preconception health when this has heightened clinical or social resonance for women may hold promise for initiating more systematic intervention. In primary care this could offer greater potential to directly engage those with low awareness or not considering pregnancy, while enlarging opportunity for others who may be seeking to conceive

  17. Enhanced soil washing process for the remediation of PBDEs/Pb/Cd-contaminated electronic waste site with carboxymethyl chitosan in a sunflower oil-water solvent system and microbial augmentation.

    PubMed

    Ye, Mao; Sun, Mingming; Wan, Jinzhong; Fang, Guodong; Li, Huixin; Hu, Feng; Jiang, Xin; Kengara, Fredrick Orori

    2015-02-01

    An innovative ex situ soil washing technology was developed to remediate polybrominated diphenyl ethers (PBDEs) and heavy metals in an electronic waste site. Elevated temperature (50 °C) in combination with ultrasonication (40 kHz, 20 min) at 5.0 mL L(-1) sunflower oil and 2.5 g L(-1) carboxymethyl chitosan were found to be effective in extracting mixed pollutants from soil. After two successive washing cycles, the removal efficiency rates for total PBDEs, BDE28, BDE47, BDE209, Pb, and Cd were approximately 94.1, 93.4, 94.3, 99.1, 89.3, and 92.7 %, respectively. Treating the second washed soil with PBDE-degrading bacteria (Rhodococcus sp. strain RHA1) inoculation and nutrient addition for 3 months led to maximum biodegradation rates of 37.3, 52.6, 23.9, and 1.3 % of the remaining total PBDEs, BDE28, BDE47, BDE209, respectively. After the combined treatment, the microbiological functions of washed soil was partially restored, as indicated by a significant increase in the counts, biomass C, N, and functioning diversity of soil microorganisms (p < 0.05), and the residual PBDEs and heavy metals mainly existed as very slow desorbing fractions and residual fractions, as evaluated by Tenax extraction combined with a first-three-compartment model and sequential extraction with metal stability indices (I R and U ts). Additionally, the secondary environmental risk of mixed contaminants in the remediated soil was limited. Therefore, the proposed combined cleanup strategy is an environment-friendly technology that is important for risk assessment and management in mixed-contaminated sites.

  18. Ethyl lactate-EDTA composite system enhances the remediation of the cadmium-contaminated soil by autochthonous willow (Salix x aureo-pendula CL 'J1011') in the lower reaches of the Yangtze River.

    PubMed

    Li, Jiahua; Sun, Yuanyuan; Yin, Ying; Ji, Rong; Wu, Jichun; Wang, Xiaorong; Guo, Hongyan

    2010-09-15

    In order to explore a practical approach to the remediation of the cadmium (Cd)-contaminated soil in the lower reaches of the Yangtze River, we evaluated the effects of a local willow (Salix x aureo-pendula CL 'J1011') of absorbing, accumulating, and translocating Cd; and assessed the potential of chelator ethylenediaminetetraacetic acid (EDTA) in combination with ethyl lactate for enhancing the efficiency of the willow in removing Cd in two water-culture growth chamber trials and a field one. The willow showed a high tolerance to Cd in growth chamber trial 1 where the Cd concentration in the medium reached up to 25 mg L(-1) medium, and the bioaccumulation factors (BAFs) of the shoots for Cd rose from 3.8 to 7.4 as the Cd concentration in the medium was elevated from 5 to 25 mg L(-1) medium. In growth chamber trial 2, the average Cd removal rates in two treatments with EDTA and ethyl lactate (molar ratios of EDTA to ethyl lactate=68/39 and 53.5/53.5, respectively) reached 0.71 mg d(-1) pot(-1) for the duration of Day 5-8 and 0.59 mg d(-1) pot(-1) for that of Day 8-11, which were 5- and 4-fold of their counterparts in the control, respectively. In the field trial, for the remediational duration of 45 days, three treatments-willow alone, willow combined with EDTA, and willow combined with EDTA and ethyl lactate-led to decreases in the Cd concentration in soil by 5%, 20%, and 29%, respectively; increases in that in the leaves by 14.6%, 56.7%, and 146.5%, respectively; and increases in that in the stems by 15.6%, 41.2%, and 87.4%, respectively, compared to their counterparts on Day 0. These results indicate that EDTA combined with ethyl lactate significantly enhanced the efficiency of willow in removing Cd from the soil. Therefore, a phytoextration system consisting of the autochthonous willow, EDTA, and ethyl lactate has high potential for the remediation of the Cd-polluted soil in the lower reaches of the Yangtze River.

  19. Diverse Amorphous Carbonaceous Thin Films Obtained by Plasma Enhanced Chemical Vapor Deposition and Plasma Immersion Ion Implantation and Deposition

    NASA Astrophysics Data System (ADS)

    Santos, R. M.; Turri, R.; Rangel, E. C.; da Cruz, N. C.; Schreiner, W.; Davanzo, C. U.; Durrant, S. F.

    Diverse amorphous hydrogenated carbon and similar films containing additional elements were produced by Plasma Enhanced Chemical Vapor Deposition (PECVD) and by Plasma Immersion Ion Implantation and Deposition (PIIID). Thus a-C:H, a-C:H:F, a-C:H:N, a-C:H:Cl and a-C:H:O:Si were obtained, starting from the same feed gases, using both techniques. The same deposition system supplied with radiofrequency (RF) power was used to produce all the films. A cylindrical stainless steel chamber equipped with circular electrodes mounted horizontally was employed. RF power was fed to the upper electrode; substrates were placed on the lower electrode. For PIIID negative high tension pulses were also applied to the lower electrode. Raman spectroscopy confirmed that all the films are amorphous. Chemical characterization of each pair of films was undertaken using Infrared Reflection Absorption Spectroscopy and X-ray Photoelectron Spectroscopy. The former revealed the presence of specific structures, such as C-H, C-O, O-H. The latter allowed calculation of the ratio of hetero-atoms to carbon atoms in the films, e.g. F:C, N:C, and Si:C. Only relatively small differences in elemental composition were detected between films produced by the two methods. The deposition rate in PIIID is generally reduced in relation to that of PECVD; for a-C:H:Cl films the reduction factor is almost four.

  20. Seed retention by pioneer trees enhances plant diversity resilience on gravel bars: Observations from the river Allier, France

    NASA Astrophysics Data System (ADS)

    Corenblit, Dov; Vidal, Vincent; Cabanis, Manon; Steiger, Johannes; Garófano-Gómez, Virginia; Garreau, Alexandre; Hortobágyi, Borbála; Otto, Thierry; Roussel, Erwan; Voldoire, Olivier

    2016-07-01

    Pioneer riparian trees which establish in river active tracts on gravel bars enhance fine sediment retention during high flows within their stands and in their lee side, forming obstacle marks. Fine sediment retention can be accompanied by deposition of seeds transported by water dispersal, i.e. by hydrochory. We tested the hypothesis that pioneer riparian trees significantly control seed deposition on gravel bars by forming sediment obstacle marks. We described the seed bank structure and compared samples collected from obstacle marks and bare coarse-grained bar surfaces. At the surface (at 2 cm depth), seed abundance (N) and richness (S) (expressed as mean ± sd) were significantly higher in areas directly affected by riparian trees, i.e. obstacle marks, (N: 693 ± 391; S: 17 ± 3) than in bare surfaces (N: 334 ± 371; S: 13 ± 5). Surface and sub-surface (at 20 cm depth) samples were also significantly different, with the sub-surface samples almost devoid of seeds (respectively N: 514 ± 413; S: 15 ± 5 and N: 3 ± 6; S: 1 ± 2). These results suggest a biogeomorphic feedback between sediment and associated seed retention mediated by hydrochory, vegetation growth and local seed dispersal mediated by barochory. Such feedback may improve plant diversity resilience on gravel alluvial bars of high-energy rivers.

  1. AMS Online Weather Studies: The National Dissemination of a Distance Learning Course for Enhancing Diversity in the Geosciences

    NASA Astrophysics Data System (ADS)

    Weinbeck, R. S.; Geer, I. W.; Mills, E. W.; Porter, W. A.; Moran, J. M.

    2004-12-01

    Our nation faces a serious challenge in attracting young people to science and science-related careers (including teaching). This is particularly true for members of groups underrepresented in science, mathematics, engineering, and technology and is especially acute in the number of minority college students majoring in the geosciences. A formidable obstacle in attracting undergraduates to the geosciences is lack of access, that is, no opportunity to enroll in geoscience courses simply because none is offered at their college or university. Often college-level introductory courses are a student's first exposure to the geosciences. To help alleviate this problem of access, the American Meteorological Society (AMS) has developed and implemented nationally an introductory weather and climate course, Online Weather Studies, which can be added to an institution's menu of general education course offerings. This highly successful course has been licensed by over 230 colleges and universities nationwide, among them 72 minority-serving institutions which have joined via the AMS Online Weather Studies Geosciences Diversity Program since 2002. This program designed to reach institutions serving large numbers of minority students has been made possible through support from the National Science Foundation (NSF) Opportunities for Enhancing Diversity in the Geosciences (OEDG) and Course, Curriculum and Laboratory Improvement-National Dissemination (CCLI-ND) programs. Online Weather Studies is an innovative, 12- to 15-week introductory college-level, online distance-learning course on the fundamentals of atmospheric science. Learner-formatted current weather data are delivered via the Internet and coordinated with investigations keyed to the day's weather. The principal innovation of Online Weather Studies is that students learn about weather as it happens in near real-time - a highly motivational learning experience. The AMS Education Program designed and services this course

  2. Enhancing Diversity in the Geosciences through National Dissemination of the AMS Online Weather Studies Distance Learning Course

    NASA Astrophysics Data System (ADS)

    Weinbeck, R. S.; Geer, I. W.; Mills, E. W.; Porter, W. A.; Moran, J. M.

    2002-12-01

    Our nation faces a serious challenge in attracting young people to science and science-related careers (including teaching). This is particularly true for members of groups underrepresented in science, mathematics, engineering, and technology and is especially acute in the number of minority college students majoring in the geosciences. A formidable obstacle in attracting undergraduates to the geosciences is lack of access, that is, no opportunity to enroll in an introductory geoscience course simply because none is offered at their college or university. Often introductory or survey courses are a student's first exposure to the geosciences. To help alleviate this problem, the American Meteorological Society (AMS) through its Education Program developed and implemented nationally an introductory weather and climate course, Online Weather Studies, which can be added to an institution's menu of general education course offerings. This highly successful course will be offered at 130 colleges and universities nationwide, including 30 minority-serving institutions, 20 of which have joined the AMS Online Weather Studies Diversity Program during 2002. The AMS encourages course adoption by more institutions serving large numbers of minority students through support from the National Science Foundation (NSF) Opportunities for Enhancing Diversity in the Geosciences (OEDG) and Course, Curriculum and Laboratory Improvement-National Dissemination (CCLI-ND) programs. Online Weather Studies is an innovative, 12- to 15-week introductory college-level, online distance-learning course on the fundamentals of atmospheric science. Learner-formatted current weather data are delivered via the Internet and coordinated with investigations keyed to the day's weather. The principal innovation of Online Weather Studies is that students learn about weather as it happens in near real-time-a highly motivational learning experience. The AMS Education Program designed and services this course and

  3. Neurophysiological Evidence for Remediation of Reward Processing Deficits in Chronic Pain and Opioid Misuse Following Treatment with Mindfulness-Oriented Recovery Enhancement: Exploratory ERP Findings from a Pilot RCT

    PubMed Central

    Garland, Eric L.; Froeliger, Brett; Howard, Matthew O.

    2014-01-01

    Dysregulated processing of natural rewards may be a central pathogenic process in the etiology and maintenance of prescription opioid misuse and addiction among chronic pain patients. This study examined whether a Mindfulness-Oriented Recovery Enhancement (MORE) intervention could enhance natural reward processing through training in savoring as indicated by event-related brain potentials (ERPs). Participants were chronic pain patients at risk for opioid misuse who were randomized to eight weeks of MORE (n=11) or a support group control condition (n=18). ERPs to images representing naturally rewarding stimuli (e.g., beautiful landscapes, intimate couples) and neutral images were measured before and after 8 weeks of treatment. Analyses focused on the late positive potential (LPP) - an ERP response in the 400 – 1000 ms time window thought to index allocation of attention to emotional information. Treatment with MORE was associated with significant increases in LPP response to natural reward stimuli relative to neutral stimuli which were correlated with enhanced positive affective cue-responses and reductions in opioid craving from pre- to post-treatment. Findings suggest that cognitive training regimens centered on strengthening attention to natural rewards may remediate reward processing deficits underpinning addictive behavior. PMID:25385024

  4. Sustainable multistage process for enhanced productivity of bioplastics from waste remediation through aerobic dynamic feeding strategy: Process integration for up-scaling.

    PubMed

    Amulya, K; Jukuri, Srinivas; Venkata Mohan, S

    2015-01-01

    Polyhydroxyalkanoates (PHA) production was evaluated in a multistage operation using food waste as a renewable feedstock. The first step involved the production of bio-hydrogen (bio-H2) via acidogenic fermentation. Volatile fatty acid (VFA) rich effluent from bio-H2 reactor was subsequently used for PHA production, which was carried out in two stages, Stage II (culture enrichment) and Stage III (PHA production). PHA-storing microorganisms were enriched in a sequencing batch reactor (SBR), operated at two different cycle lengths (CL-24; CL-12). Higher polymer recovery as well as VFA removal was achieved in CL-12 operation both in Stage II (16.3% dry cell weight (DCW); VFA removal, 84%) and Stage III (23.7% DCW; VFA removal, 88%). The PHA obtained was a co-polymer [P(3HB-co-3HV)] of PHB and PHV. The results obtained indicate that this integrated multistage process offers new opportunities to further leverage large scale PHA production with simultaneous waste remediation in the framework of biorefinery.

  5. Sustainable multistage process for enhanced productivity of bioplastics from waste remediation through aerobic dynamic feeding strategy: Process integration for up-scaling.

    PubMed

    Amulya, K; Jukuri, Srinivas; Venkata Mohan, S

    2015-01-01

    Polyhydroxyalkanoates (PHA) production was evaluated in a multistage operation using food waste as a renewable feedstock. The first step involved the production of bio-hydrogen (bio-H2) via acidogenic fermentation. Volatile fatty acid (VFA) rich effluent from bio-H2 reactor was subsequently used for PHA production, which was carried out in two stages, Stage II (culture enrichment) and Stage III (PHA production). PHA-storing microorganisms were enriched in a sequencing batch reactor (SBR), operated at two different cycle lengths (CL-24; CL-12). Higher polymer recovery as well as VFA removal was achieved in CL-12 operation both in Stage II (16.3% dry cell weight (DCW); VFA removal, 84%) and Stage III (23.7% DCW; VFA removal, 88%). The PHA obtained was a co-polymer [P(3HB-co-3HV)] of PHB and PHV. The results obtained indicate that this integrated multistage process offers new opportunities to further leverage large scale PHA production with simultaneous waste remediation in the framework of biorefinery. PMID:25682477

  6. Designing Clinical Remediation Programs.

    ERIC Educational Resources Information Center

    Oleszewski, Susan C.

    1989-01-01

    Elements and considerations in the provision of effective remediation for optometry students not achieving in clinical competence are discussed. Remediation of technical, cognitive, and noncognitive skills are included. A course in professional communication offered by the Pennsylvania College of Optometry is described. (MSE)

  7. Preventing remediation problems

    SciTech Connect

    Fleming, W.H.

    1994-12-31

    Remediation, the design and construction of a remedy, typically represents the most significant portion of the cleanup process. The cost may be 5 to 10 times the cost of earlier investigation and feasibility efforts. Furthermore, the risks associated with remediation activities and their ability to meet ultimate cleanup goals and objectives are far greater than those associated with earlier efforts. Often times there are unrealistic expectations interjected throughout the design and construction process in the remediation field. The simple fact that most problems are buried, and one cannot see all that is below the ground surface provides sufficient uncertainty to result in problems. There are three key points during the remediation process which provide opportunities to prevent and avoid problems. These are: (1) during design; (2) during procurement and contracting; and (3) during construction. This paper examines actions which the author has found or believes will assist in providing a formula for success.

  8. Cognitive Remediation in Severe Mental Illness

    PubMed Central

    Bowie, Christopher R.

    2012-01-01

    Cognitive enhancement has received substantial recent attention because of multiple recent successes. We review the current research literature on cognitive enhancement, focusing on new developments that separate previous less successful efforts from recent successes. These innovations include increased understanding of the dosing and spacing of sessions, the need for titration of difficulty of individual sessions, and the importance of concurrent interventions. We also review the domains of functioning shown to be improved by cognitive remediation and the possibility that some biomarkers improve as well. We close by noting that current societal factors may impose limitations on the benefits accrued from cognitive remediation and also note that some pharmacological treatments, such as anticholinergic medications, may reduce or eliminate the potential benefits from cognitive remediation. PMID:22666639

  9. Neurophysiological evidence for remediation of reward processing deficits in chronic pain and opioid misuse following treatment with Mindfulness-Oriented Recovery Enhancement: exploratory ERP findings from a pilot RCT.

    PubMed

    Garland, Eric L; Froeliger, Brett; Howard, Matthew O

    2015-04-01

    Dysregulated processing of natural rewards may be a central pathogenic process in the etiology and maintenance of prescription opioid misuse and addiction among chronic pain patients. This study examined whether a Mindfulness-Oriented Recovery Enhancement (MORE) intervention could augment natural reward processing through training in savoring as indicated by event-related brain potentials (ERPs). Participants were chronic pain patients at risk for opioid misuse who were randomized to 8 weeks of MORE (n = 11) or a support group control condition (n = 18). ERPs to images representing naturally rewarding stimuli (e.g., beautiful landscapes, intimate couples) and neutral images were measured before and after 8 weeks of treatment. Analyses focused on the late positive potential (LPP)--an ERP response in the 400-1,000 ms time window thought to index allocation of attention to emotional information. Treatment with MORE was associated with significant increases in LPP response to natural reward stimuli relative to neutral stimuli which were correlated with enhanced positive affective cue-responses and reductions in opioid craving from pre- to post-treatment. Findings suggest that cognitive training regimens centered on strengthening attention to natural rewards may remediate reward processing deficits underpinning addictive behavior.

  10. Enhancing the Efficacy of Lecturers in Educating Student Cohorts Consisting of Culturally Diverse Groups in a Medical University

    ERIC Educational Resources Information Center

    Chakravarthi, Srikumar; Haleagrahara, Nagaraja; Judson, John Paul

    2010-01-01

    Lecturers exert a potent influence over the achievement of all students, low-income culturally diverse students in particular. Although recent research has confirmed that lecturer involvement is critical for promoting academic engagement of low-income and ethnically diverse students in America and other countries, other literature suggests that…

  11. A Case Study on a Diverse College Algebra Classroom: Analyzing Pedagogical Strategies to Enhance Students' Mathematics Self-Efficacy

    ERIC Educational Resources Information Center

    Furuto, Michael

    2013-01-01

    Shifting demographics show America rapidly diversifying, yet research indicates that an alarming number of diverse students continue to struggle to meet learning outcomes of collegiate mathematics curriculum. Consequently, recruitment and retention of diverse students in STEM majors is a pervasive issue. Using a sociocultural perspective, this…

  12. Hazardous waste site remediation and community acceptance: Beyond regulatory compliance

    SciTech Connect

    Howard, M.A.; Moreau, J.P.

    1998-12-31

    Community acceptance is an important criteria in securing regulatory approval of remediation alternatives, and yet the legal requirements for public consultation during the preparation of site investigation and feasibility study reports are minimal. Usually the only provision for formal public input on remedial plans is at the final stages of preparation through the formalistic constraints of a public meeting and limited comment period. This is often too late for meaningful public input and precludes constructive dialogue between responsible parties, local citizens, and regulatory representatives. Often the public opposes proposed remediation alternatives because of insufficient information leading to mistrust and irreconcilable differences. This paper suggests that responsible parties run the risk of community rejection of remediation plans, and costly project delays, if they follow the minimum regulatory requirements for public involvement. Through the use of active and meaningful citizen participation throughout project planning, success in securing community acceptance for preferred remedial alternatives in potentially controversial remediation projects is greatly enhanced.

  13. Unconventional cancer remedies.

    PubMed Central

    Danielson, K J; Stewart, D E; Lippert, G P

    1988-01-01

    Unproven and disproven remedies continue to abound for illnesses for which conventional treatment is only partially effective. This is particularly true with cancer, for which up to 50% of patients may be receiving unorthodox therapy. This article examines unconventional cancer remedies, their adverse effects, their common factors and the basis for their appeal, as well as what motivates and characterizes patients who choose these treatments. Also discussed is an approach that may be used by the conventional physician for patients who are likely to seek unorthodox treatment. This approach will help patients make the best decision about their treatment and protect them from the hazards of unconventional remedies. PMID:3285984

  14. REMEDIATION OF CONTAMINATED SOILS BY SOLVENT FLUSHING

    EPA Science Inventory

    Solvent flushing is a potential technique for remediating a waste disposal/spill site contaminated with organic chemicals. This technique involves the injection of a solvent mixture (e.g., water plus alcohols) that enhances contaminant solubility, reduces the retardation factor, ...

  15. C60/Bi2TiO4F2 heterojunction photocatalysts with enhanced visible-light activity for environmental remediation.

    PubMed

    Li, Guisheng; Jiang, Bo; Li, Xin; Lian, Zichao; Xiao, Shuning; Zhu, Jian; Zhang, Dieqing; Li, Hexing

    2013-08-14

    Fullerene (C60)-enhanced Bi2TiO4F2 hierarchical microspheres were prepared by a facile solvothermal method. Compared to the pure Bi2TiO4F2 photocatalyst, the C60/Bi2TiO4F2 samples exhibit much stronger photocatalytic performance for degrading Rhodamine B (RhB) and Eosin Y (EY) under visible light irradiation. Such greatly enhanced photocatalytic activity may be ascribed to strong combination and heterojunctions between C60 and Bi2TiO4F2, favorable for charge separation and light adsorption. Loading C60 on Bi2TiO4F2 results in a new photocatalytic mechanism (based on photo-generated hvb(+) and ·O2(-) radicals) different from that of pure Bi2TiO4F2. PMID:23834299

  16. APS Education and Diversity Efforts

    NASA Astrophysics Data System (ADS)

    Prestridge, Katherine; Hodapp, Theodore

    2015-11-01

    American Physical Society (APS) has a wide range of education and diversity programs and activities, including programs that improve physics education, increase diversity, provide outreach to the public, and impact public policy. We present the latest programs spearheaded by the Committee on the Status of Women in Physics (CSWP), with highlights from other diversity and education efforts. The CSWP is working to increase the fraction of women in physics, understand and implement solutions for gender-specific issues, enhance professional development opportunities for women in physics, and remedy issues that impact gender inequality in physics. The Conferences for Undergraduate Women in Physics, Professional Skills Development Workshops, and our new Professional Skills program for students and postdocs are all working towards meeting these goals. The CSWP also has site visit and conversation visit programs, where department chairs request that the APS assess the climate for women in their departments or facilitate climate discussions. APS also has two significant programs to increase participation by underrepresented minorities (URM). The newest program, the APS National Mentoring Community, is working to provide mentoring to URM undergraduates, and the APS Bridge Program is an established effort that is dramatically increasing the number of URM PhDs in physics.

  17. Environmental Remediation Data Management Tools

    SciTech Connect

    Wierowski, J. V.; Henry, L. G.; Dooley, D. A.

    2002-02-26

    Computer software tools for data management can improve site characterization, planning and execution of remediation projects. This paper discusses the use of two such products that have primarily been used within the nuclear power industry to enhance the capabilities of radiation protection department operations. Advances in digital imaging, web application development and programming technologies have made development of these tools possible. The Interactive Visual Tour System (IVTS) allows the user to easily create and maintain a comprehensive catalog containing digital pictures of the remediation site. Pictures can be cataloged in groups (termed ''tours'') that can be organized either chronologically or spatially. Spatial organization enables the user to ''walk around'' the site and view desired areas or components instantly. Each photo is linked to a map (floor plan, topographical map, elevation drawing, etc.) with graphics displaying the location on the map and any available tour/component links. Chronological organization enables the user to view the physical results of the remediation efforts over time. Local and remote management teams can view these pictures at any time and from any location. The Visual Survey Data System (VSDS) allows users to record survey and sample data directly on photos and/or maps of areas and/or components. As survey information is collected for each area, survey data trends can be reviewed for any repetitively measured location or component. All data is stored in a Quality Assurance (Q/A) records database with reference to its physical sampling point on the site as well as other information to support the final closeout report for the site. The ease of use of these web-based products has allowed nuclear power plant clients to plan outage work from their desktop and realize significant savings with respect to dose and cost. These same tools are invaluable for remediation and decommissioning planning of any scale and for recording

  18. Remedial action planning for Trench 1

    SciTech Connect

    Primrose, A.; Sproles, W.; Burmeister, M.; Wagner, R.; Law, J.; Greengard, T.

    1998-07-01

    The accelerated action to remove the depleted uranium chips and associated soils and wastes from Trench 1 at the Rocky Flats Environmental Technology Site (RFETS) will begin in June 1998. To ensure that the remedial action is conducted safely, a rigorous and disciplined planning process was followed that incorporates the principles of Integrated Safety Management and Enhanced Work Planning. Critical to the success of the planning was early involvement of project staff (salaried and hourly) and associated technical support groups and disciplines. Feedback was and will continue to be solicited, and lessons learned incorporated to ensure the safe remediation of this site.

  19. High-performance liquid chromatography-diode array detection of trichloroethene and aromatic and aliphatic anionic surfactants used for surfactant-enhanced aquifer remediation.

    PubMed

    Field, J A; Sawyer, T E

    2000-10-01

    A method utilizing direct aqueous injection with high-performance liquid chromatography and diode array detection (HPLC-DAD) is presented for the quantitation determination of trichloroethene (TCE) in the presence of anionic surfactants that are used to enhance the recovery of dense non-aqueous phase liquids from contaminated groundwater aquifers. The anionic surfactants investigated in this study including alkyl diphenyloxide disulfonate (Dowfax 8390) and dihexylsulfosuccinate (Aerosol MA 80-1) are used to enhance the solubility, and hence recovery, of TCE. In this type of environmental engineering application, the levels of surfactants and TCE encountered are very high (part per million to part per thousand). The anionic surfactants and TCE are quantitatively determined by direct aqueous injection onto a reversed-phase HPLC column with diode array detection. The quantitation limits of the method obtained using 100 microl injections are 0.1 mg/l for alkyl diphenyloxide disulfonates, 20 mg/l for dihexylsulfosuccinate, and 0.05 mg/l for TCE. This approach is advantageous over using gas chromatography for TCE and HPLC for the surfactants because the use of a single analytical instrument reduces sample preparation and analysis times, which increases sample throughput.

  20. Effect of electrokinetic remediation on indigenous microbial activity and community within diesel contaminated soil.

    PubMed

    Kim, Seong-Hye; Han, Hyo-Yeol; Lee, You-Jin; Kim, Chul Woong; Yang, Ji-Won

    2010-07-15

    Electrokinetic remediation has been successfully used to remove organic contaminants and heavy metals within soil. The electrokinetic process changes basic soil properties, but little is known about the impact of this remediation technology on indigenous soil microbial activities. This study reports on the effects of electrokinetic remediation on indigenous microbial activity and community within diesel contaminated soil. The main removal mechanism of diesel was electroosmosis and most of the bacteria were transported by electroosmosis. After 25 days of electrokinetic remediation (0.63 mA cm(-2)), soil pH developed from pH 3.5 near the anode to pH 10.8 near the cathode. The soil pH change by electrokinetics reduced microbial cell number and microbial diversity. Especially the number of culturable bacteria decreased significantly and only Bacillus and strains in Bacillales were found as culturable bacteria. The use of EDTA as an electrolyte seemed to have detrimental effects on the soil microbial activity, particularly in the soil near the cathode. On the other hand, the soil dehydrogenase activity was enhanced close to the anode and the analysis of microbial community structure showed the increase of several microbial populations after electrokinetics. It is thought that the main causes of changes in microbial activities were soil pH and direct electric current. The results described here suggest that the application of electrokinetics can be a promising soil remediation technology if soil parameters, electric current, and electrolyte are suitably controlled based on the understanding of interaction between electrokinetics, contaminants, and indigenous microbial community. PMID:20452646

  1. HANFORD GROUNDWATER REMEDIATION

    SciTech Connect

    CHARBONEAU, B; THOMPSON, M; WILDE, R.; FORD, B.; GERBER, M.S.

    2006-02-01

    By 1990 nearly 50 years of producing plutonium put approximately 1.70E + 12 liters (450 billion gallons) of liquid wastes into the soil of the 1,518-square kilometer (586-square mile) Hanford Site in southeast Washington State. The liquid releases consisted of chemicals used in laboratory experiments, manufacturing and rinsing uranium fuel, dissolving that fuel after irradiation in Hanford's nuclear reactors, and in liquefying plutonium scraps needed to feed other plutonium-processing operations. Chemicals were also added to the water used to cool Hanford's reactors to prevent corrosion in the reactor tubes. In addition, water and acid rinses were used to clean plutonium deposits from piping in Hanford's large radiochemical facilities. All of these chemicals became contaminated with radionuclides. As Hanford raced to help win World War II, and then raced to produce materials for the Cold War, these radioactive liquid wastes were released to the Site's sandy soils. Early scientific experiments seemed to show that the most highly radioactive components of these liquids would bind to the soil just below the surface of the land, thus posing no threat to groundwater. Other experiments predicted that the water containing most radionuclides would take hundreds of years to seep into groundwater, decaying (or losing) most of its radioactivity before reaching the groundwater or subsequently flowing into the Columbia River, although it was known that some contaminants like tritium would move quickly. Evidence today, however, shows that many contaminants have reached the Site's groundwater and the Columbia River, with more on its way. Over 259 square kilometers (100 square miles) of groundwater at Hanford have contaminant levels above drinking-water standards. Also key to successfully cleaning up the Site is providing information resources and public-involvement opportunities to Hanford's stakeholders. This large, passionate, diverse, and geographically dispersed community is

  2. Hanford Groundwater Remediation

    SciTech Connect

    Charboneau, B.; Thompson, K. M.; Wilde, R.; Ford, B.; Gerber, M.

    2006-07-01

    By 1990 nearly 50 years of producing plutonium put approximately 1.70 E+12 liters (450 billion gallons) of liquid wastes into the soil of the 1,518-square kilometer (586-square mile) Hanford Site in southeast Washington State. The liquid releases consisted of chemicals used in laboratory experiments, manufacturing and rinsing uranium fuel, dissolving that fuel after irradiation in Hanford's nuclear reactors, and in liquefying plutonium scraps needed to feed other plutonium-processing operations. Chemicals were also added to the water used to cool Hanford's reactors to prevent corrosion in the reactor tubes. In addition, water and acid rinses were used to clean plutonium deposits from piping in Hanford's large radiochemical facilities. All of these chemicals became contaminated with radionuclides. As Hanford raced to help win World War II, and then raced to produce materials for the Cold War, these radioactive liquid wastes were released to the Site's sandy soils. Early scientific experiments seemed to show that the most highly radioactive components of these liquids would bind to the soil just below the surface of the land, thus posing no threat to groundwater. Other experiments predicted that the water containing most radionuclides would take hundreds of years to seep into groundwater, decaying (or losing) most of its radioactivity before reaching the groundwater or subsequently flowing into the Columbia River, although it was known that some contaminants like tritium would move quickly. Evidence today, however, shows that many contaminants have reached the Site's groundwater and the Columbia River, with more on its way. Over 259 square kilometers (100 square miles) of groundwater at Hanford have contaminant levels above drinking-water standards. Also key to successfully cleaning up the Site is providing information resources and public-involvement opportunities to Hanford's stakeholders. This large, passionate, diverse, and geographically dispersed community is

  3. Enhancing pediatric workforce diversity and providing culturally effective pediatric care: implications for practice, education, and policy making.

    PubMed

    2013-10-01

    This policy statement serves to combine and update 2 previously independent but overlapping statements from the American Academy of Pediatrics (AAP) on culturally effective health care (CEHC) and workforce diversity. The AAP has long recognized that with the ever-increasing diversity of the pediatric population in the United States, the health of all children depends on the ability of all pediatricians to practice culturally effective care. CEHC can be defined as the delivery of care within the context of appropriate physician knowledge, understanding, and appreciation of all cultural distinctions, leading to optimal health outcomes. The AAP believes that CEHC is a critical social value and that the knowledge and skills necessary for providing CEHC can be taught and acquired through focused curricula across the spectrum of lifelong learning. This statement also addresses workforce diversity, health disparities, and affirmative action. The discussion of diversity is broadened to include not only race, ethnicity, and language but also cultural attributes such as gender, religious beliefs, sexual orientation, and disability, which may affect the quality of health care. The AAP believes that efforts must be supported through health policy and advocacy initiatives to promote the delivery of CEHC and to overcome educational, organizational, and other barriers to improving workforce diversity. PMID:24081998

  4. Remediation; An overview

    SciTech Connect

    Bishop, J.

    1988-09-01

    The U.SD. government began committing the nation legally and financially in the last decade to the ultimate remediation of virtually all of the hazardous wastes that were produced in the past and remain to threaten human health and the environment, all that continue to be generated, and all that will be created in the future. Whether engendered by acts of God or human industry, the laws and regulations mandate, hazardous wastes and the threats they pose will be removed or rendered harmless. As mobilization for tackling the monumental task implied by those commitments has progressed, key concepts have changed in meaning. The remedy of remediation once literally meant burying our hazardous waste problems in landfills, for example, a solution now officially defined as the least desirable-although still commonly chosen - course of action. The process of identifying hazardous substances and determining in what quantities they constitute health and environmental hazards continues apace. As measurement technologies become increasingly precise and capable to detecting more 9s to the right of the decimal point, acceptable levels of emissions into the air and concentrations in the ground or water are reduced. This article is intended as a sketch of where the national commitment of remediation currently stands, with examples of implications for both generators of hazardous wastes and those who have entered-or seek to enter-the rapidly growing business of remediation.

  5. 13 CFR 108.1810 - Events of default and SBA's remedies for NMVC Company's noncompliance with terms of Debentures.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... substantive regulation promulgated under the Act. (9) Failure to maintain diversity. You fail to maintain diversity between management and ownership as required by § 108.150. (g) SBA remedies for events of...

  6. Enhanced proliferation of fibroblasts and endothelial cells treated with an extract of the leaves of Chromolaena odorata (Eupolin), an herbal remedy for treating wounds.

    PubMed

    Phan, T T; Hughes, M A; Cherry, G W

    1998-03-01

    Burns are a major problem in many developing countries. Eupolin ointment is a topical agent used in the treatment of soft-tissue wounds and burns in Vietnam and is made from an aqueous extract of the leaves of Chromolaena odorata (formerly Eupatorium odoratum). Clinical studies using this extract have shown antimicrobial and anticoagulation effects as well as the promotion of tissue remodeling in the wound healing process. However, the mechanism by which this agent affects cells involved in the wound healing process is unknown. In our research, fibroblasts and endothelial cells, two cell types that play a crucial role in wound healing, were used to investigate some of the effects of Eupolin extract in vitro. Cell growth was estimated by a colorimetric assay at different time intervals. Enhanced growth of fibroblasts and endothelial cells was found at concentrations of 10 microg/ml and 100 microg/ml of Eupolin extract. This was particularly evident in medium supplemented with only 0.5% fetal calf serum where the cells were quiescent. Toxicity of the extract to fibroblasts was observed at 250 microg/ml in Dulbecco's modified Eagle's medium/0.5% fetal calf serum, but there was no significant damage at this dose to the endothelial cells. The results of the study demonstrated that Eupolin extract increased fibroblast and endothelial cell growth, and this could explain in part the beneficial clinical effects that have been observed.

  7. Restructuring reward processing with Mindfulness-Oriented Recovery Enhancement: novel therapeutic mechanisms to remediate hedonic dysregulation in addiction, stress, and pain.

    PubMed

    Garland, Eric L

    2016-06-01

    Though valuation processes are fundamental to survival of the human species, hedonic dysregulation is at the root of an array of maladies, including addiction, stress, and chronic pain, as evidenced by the allostatic shift in the relative salience of natural reward to drug reward observed among persons with severe substance use disorders. To address this crucial problem, novel interventions are needed to restore hedonic regulatory processes gone awry in persons exhibiting addictive behaviors. This article describes a theoretical rationale and empirical evidence for the effects of one such new intervention, Mindfulness-Oriented Recovery Enhancement (MORE), on top-down and bottom-up mechanisms implicated in cognitive control and hedonic regulation. MORE is innovative and distinct from extant mindfulness-based interventions in that it unites traditional mindfulness meditation with reappraisal and savoring strategies designed to reverse the downward shift in salience of natural reward relative to drug reward, representing a crucial tipping point to disrupt the progression of addiction-a mechanistic target that no other behavioral intervention has been designed to address. Though additional studies are needed, clinical and biobehavioral data from several completed and ongoing trials suggest that MORE may exert salutary effects on addictive behaviors and the neurobiological processes that underpin them.

  8. Restructuring reward processing with Mindfulness-Oriented Recovery Enhancement: novel therapeutic mechanisms to remediate hedonic dysregulation in addiction, stress, and pain.

    PubMed

    Garland, Eric L

    2016-06-01

    Though valuation processes are fundamental to survival of the human species, hedonic dysregulation is at the root of an array of maladies, including addiction, stress, and chronic pain, as evidenced by the allostatic shift in the relative salience of natural reward to drug reward observed among persons with severe substance use disorders. To address this crucial problem, novel interventions are needed to restore hedonic regulatory processes gone awry in persons exhibiting addictive behaviors. This article describes a theoretical rationale and empirical evidence for the effects of one such new intervention, Mindfulness-Oriented Recovery Enhancement (MORE), on top-down and bottom-up mechanisms implicated in cognitive control and hedonic regulation. MORE is innovative and distinct from extant mindfulness-based interventions in that it unites traditional mindfulness meditation with reappraisal and savoring strategies designed to reverse the downward shift in salience of natural reward relative to drug reward, representing a crucial tipping point to disrupt the progression of addiction-a mechanistic target that no other behavioral intervention has been designed to address. Though additional studies are needed, clinical and biobehavioral data from several completed and ongoing trials suggest that MORE may exert salutary effects on addictive behaviors and the neurobiological processes that underpin them. PMID:27037786

  9. Enhanced tolerance and remediation to mixed contaminates of PCBs and 2,4-DCP by transgenic alfalfa plants expressing the 2,3-dihydroxybiphenyl-1,2-dioxygenase.

    PubMed

    Wang, Yan; Ren, Hejun; Pan, Hongyu; Liu, Jinliang; Zhang, Lanying

    2015-04-01

    Polychlorinated biphenyls (PCBs) and 2,4-dichlorophenol (2,4-DCP) generally led to mixed contamination of soils as a result of commercial and agricultural activities. Their accumulation in the environment poses great risks to human and animal health. Therefore, the effective strategies for disposal of these pollutants are urgently needed. In this study, genetic engineering to enhance PCBs/2,4-DCP phytoremediation is a focus. We cloned the 2,3-dihydroxybiphenyl-1,2-dioxygenase (BphC.B) from a soil metagenomic library, which is the key enzyme of aerobic catabolism of a variety of aromatic compounds, and then it was expressed in alfalfa driven by CaMV 35S promoter using Agrobacterium-mediated transformation. Transgenic line BB11 was selected out through PCR, Western blot analysis and enzyme activity assays. Its disposal and tolerance to both PCBs and 2,4-DCP were examined. The tolerance capability of transgenic line BB11 towards complex contaminants of PCBs/2,4-DCP significantly increased compared with non-transgenic plants. Strong dissipation of PCBs and high removal efficiency of 2,4-DCP were exhibited in a short time. It was confirmed expressing BphC.B would be a feasible strategy to help achieving phytoremediation in mixed contaminated soils with PCBs and 2,4-DCP.

  10. Remedial design/remedial action strategy report

    SciTech Connect

    Dieffenbacher, R.G.

    1994-06-30

    This draft Regulatory Compliance Strategy (RCS) report will aid the ER program in developing and implementing Remedial Design/Remedial Action (RD/RA) projects. The intent of the RCS is to provide guidance for the implementation of project management requirements and to allow the implementation of a flexible, graded approach to design requirements depending on the complexity, magnitude, schedule, risk, and cost for any project. The RCS provides a functional management-level guidance document for the identification, classification, and implementation of the managerial and regulatory aspects of an ER project. The RCS has been written from the perspective of the ER Design Manager and provides guidance for the overall management of design processes and elements. The RCS does not address the project engineering or specification level of detail. Topics such as project initiation, funding, or construction are presented only in the context in which these items are important as sources of information or necessary process elements that relate to the design project phases.

  11. Solutions Remediate Contaminated Groundwater

    NASA Technical Reports Server (NTRS)

    2010-01-01

    During the Apollo Program, NASA workers used chlorinated solvents to clean rocket engine components at launch sites. These solvents, known as dense non-aqueous phase liquids, had contaminated launch facilities to the point of near-irreparability. Dr. Jacqueline Quinn and Dr. Kathleen Brooks Loftin of Kennedy Space Center partnered with researchers from the University of Central Florida's chemistry and engineering programs to develop technology capable of remediating the area without great cost or further environmental damage. They called the new invention Emulsified Zero-Valent Iron (EZVI). The groundwater remediation compound is cleaning up polluted areas all around the world and is, to date, NASA's most licensed technology.

  12. The Use of Ecological Restoration Principles To Achieve Remedy Protection At the Fernald Preserve and Weldon Spring Sites

    SciTech Connect

    Powell, J.; Johnston, F.; Homer, J.; Deyo, Y.

    2008-07-01

    At both the Fernald Preserve and the Weldon Spring Site, the development of ecological restoration goals and objectives was used to complement and even enhance achievement of selected remedies. Warm-season native grasses and forbs were used for revegetation of remediated areas. The hardiness and ability to establish in low-nutrient conditions make native grasses ideal candidates for reestablishment of vegetation in excavated areas. At the Fernald Preserve, native grasses were used for vegetative cover on an on-site disposal facility as well. Also at the Fernald Preserve, excavation footprints were optimized to increase the quantity and quality of created wetlands. Drainage features in a couple instances provide passive groundwater recharge, potentially accelerating groundwater remediation efforts. In addition, a number of clean materials and structures were beneficially reused as part of ecological restoration designs, including wood-chip mulch and woody debris, clean concrete, and a rail trestle. At the Weldon Spring Site, several methods were used to control erosion for three years after the initial seeding of native species. A field evaluation of soil conditions and general species diversity was performed in 2007 and it was determined that erosion at the site was typical and repairing naturally. These approaches resulted in 'win-win' strategies needed to successfully remediate and restore complex projects such as the Fernald Preserve and Weldon Spring. (authors)

  13. Efficacy of CERCLA remedies in light of five-year reviews.

    SciTech Connect

    Hocking, E. K.; Martino, L.; Environmental Assessment

    2003-01-01

    Reviews of several remedies selected and implemented under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended, revealed deficiencies in remedy protectiveness although the remedy had only been in place for five years. Many of these deficiencies should have been foreseeable, and therefore preventable, at the time the remedy was selected. Analysis of successes and deficiencies noted in the CERCLA five-year reviews highlights the pivotal role that monitoring plans and land use controls have in ensuring remedy protectiveness. The analysis demonstrated that remedy protectiveness assessments and remedy modification justifications depend on robust site and remedy monitoring plans as well as on adequately developed conceptual site models. Comprehensive understanding and inferences regarding past, present, and future land and resource use at the remedy selection stage can enhance remedy protectiveness because stakeholders can determine if land use controls are necessary and if they can be implemented and enforced. The findings from this analysis of five-year reviews of remedy protectiveness are applicable to initial remedy selection decisions and subsequent enhancements of their effectiveness through time.

  14. Ecosystem engineering by invasive exotic beavers reduces in-stream diversity and enhances ecosystem function in Cape Horn, Chile.

    PubMed

    Anderson, Christopher B; Rosemond, Amy D

    2007-11-01

    Species invasions are of global significance, but predicting their impacts can be difficult. Introduced ecosystem engineers, however, provide an opportunity to test the underlying mechanisms that may be common to all invasive engineers and link relationships between changes in diversity and ecosystem function, thereby providing explanatory power for observed ecological patterns. Here we test specific predictions for an invasive ecosystem engineer by quantifying the impacts of habitat and resource modifications caused by North American beavers (Castor canadensis) on aquatic macroinvertebrate community structure and stream ecosystem function in the Cape Horn Biosphere Reserve, Chile. We compared responses to beavers in three habitat types: (1) forested (unimpacted) stream reaches, (2) beaver ponds, and (3) sites immediately downstream of beaver dams in four streams. We found that beaver engineering in ponds created taxonomically simplified, but more productive, benthic macroinvertebrate assemblages. Specifically, macroinvertebrate richness, diversity and number of functional feeding groups were reduced by half, while abundance, biomass and secondary production increased three- to fivefold in beaver ponds compared to forested sites. Reaches downstream of beaver ponds were very similar to natural forested sections. Beaver invasion effects on both community and ecosystem parameters occurred predominantly via increased retention of fine particulate organic matter, which was associated with reduced macroinvertebrate richness and diversity (via homogenization of benthic microhabitat) and increased macroinvertebrate biomass and production (via greater food availability). Beaver modifications to macroinvertebrate community structure were largely confined to ponds, but increased benthic production in beaver-modified habitats adds to energy retention and flow for the entire stream ecosystem. Furthermore, the effects of beavers on taxa richness (negative) and measures of

  15. Modularizing Remedial Mathematics

    ERIC Educational Resources Information Center

    Wong, Aaron

    2013-01-01

    As remedial mathematics education has become an increasingly important topic of conversation in higher education. Mathematics departments have been put under increased pressure to change their programs to increase the student success rate. A number of models have been introduced over the last decade that represent a wide range of new ideas and…

  16. COST OF MTBE REMEDIATION

    EPA Science Inventory

    Widespread contamination of methyl tert-butyl ether (MTBE) in ground water has raised concerns about the increased cost of remediation of MTBE releases compared to BTEX-only sites. To evaluate these cost, cost information for 311 sites was furnished by U.S. EPA Office of Undergr...

  17. 2014 Ohio Remediation Report

    ERIC Educational Resources Information Center

    Ohio Board of Regents, 2014

    2014-01-01

    In fulfillment of Ohio Revised Code 3333.041 (A) (1) the Chancellor has published a listing by school district of the number of the 2013 high school graduates who attended a state institution of higher education in academic year 2013-2014 and the percentage of each district's graduates required by the institution to enroll in a remedial course in…

  18. [Cognitive remediation and nursing care].

    PubMed

    Schenin-King, Palmyre; Thomas, Fanny; Braha-Zeitoun, Sonia; Bouaziz, Noomane; Januel, Dominique

    2016-01-01

    Therapies based on cognitive remediation integrate psychiatric care. Cognitive remediation helps to ease cognitive disorders and enable patients to improve their day-to-day lives. It is essential to complete nurses' training in this field. This article presents the example of a patient with schizophrenia who followed the Cognitive Remediation Therapy programme, enabling him to access mainstream employment. PMID:27615702

  19. Innovative vitrification for soil remediation

    SciTech Connect

    Jetta, N.W.; Patten, J.S.; Hart, J.G.

    1995-12-01

    The objective of this DOE demonstration program is to validate the performance and operation of the Vortec Cyclone Melting System (CMS{trademark}) for the processing of LLW contaminated soils found at DOE sites. This DOE vitrification demonstration project has successfully progressed through the first two phases. Phase 1 consisted of pilot scale testing with surrogate wastes and the conceptual design of a process plant operating at a generic DOE site. The objective of Phase 2, which is scheduled to be completed the end of FY 95, is to develop a definitive process plant design for the treatment of wastes at a specific DOE facility. During Phase 2, a site specific design was developed for the processing of LLW soils and muds containing TSCA organics and RCRA metal contaminants. Phase 3 will consist of a full scale demonstration at the DOE gaseous diffusion plant located in Paducah, KY. Several DOE sites were evaluated for potential application of the technology. Paducah was selected for the demonstration program because of their urgent waste remediation needs as well as their strong management and cost sharing financial support for the project. During Phase 2, the basic nitrification process design was modified to meet the specific needs of the new waste streams available at Paducah. The system design developed for Paducah has significantly enhanced the processing capabilities of the Vortec vitrification process. The overall system design now includes the capability to shred entire drums and drum packs containing mud, concrete, plastics and PCB`s as well as bulk waste materials. This enhanced processing capability will substantially expand the total DOE waste remediation applications of the technology.

  20. Almost remediation of saltwater spills at E and P sites

    SciTech Connect

    Carty, D.J.

    1995-12-31

    At exploration and production (E and P) sites crude spills restricted to topsoil are often self-remediating, but salt spills rarely are. Most soils naturally biodegrade crude. Without appropriate human intervention, brine spills can result in decades of barren land and seriously degrade surface water and aquifers. Servicing the E and P industry are remediation practitioners with a limited array of often expensive remediation concepts and materials which they hope will work, and sometimes do. Unfortunately, many remediation practitioners are unfamiliar with, or disregard, the natural physical, chemical, and biotic complexity of the soil and aquatic media. All too often this results in exacerbating injury to an already damaged ecosystem. Likewise, important cultural factors such as public relations, environmental regulations, property rights, and water rights are also overlooked until after implementation of an ill-advised or illegal remediation design has been initiated. A major issue is determining what constitutes ``successful`` remediation of a brine spill. Environmental managers have long sought one or two universally applicable fast and cheap amendment/treatment protocols for all their diverse multi-state salt affected spill scenarios. This presentation describes aspects of common spill-affected ecosystems which must be considered to achieve ``successful`` remediation.

  1. Effects of remediation amendments on vadose zone microorganisms

    SciTech Connect

    Miller, Hannah M.; Tilton, Fred A.

    2012-08-10

    Surfactant-based foam delivery technology has been studied to remediate Hanford 200 area deep vadose zone sediment. However, the surfactants and remediation amendments have an unknown effect on indigenous subsurface microorganisms. Microbial populations are important factors to consider in remediation efforts due to their potential to alter soil geochemistry. This project focuses on measuring microbial metabolic responses to remediation amendments in batch and column studies using Deep Vadose Zone Sediments. Initial studies of the microbes from Hanford 200 area deep vadose zone sediment showed surfactants sodium dodecyl sulfate (SDS) and cocamidopropyl betaine (CAPB) and remediation amendment calcium polysulfide (CPS) had no affect on microbial growth using BiologTM Ecoplates. To move towards a more realistic field analog, soil columns were packed with Hanford 200 Area sediment. Once microbial growth in the column was verified by observing growth of the effluent solution on tryptic soy agar plates, remedial surfactants were injected into the columns, and the resulting metabolic diversity was measured. Results suggest surfactant sodium dodecyl sulfate (SDS) stimulates microbial growth. The soil columns were also visualized using X-ray microtomography to inspect soil packing and possibly probe for evidence of biofilms. Overall, BiologTM Ecoplates provide a rapid assay to predict effects of remediation amendments on Hanford 200 area deep vadose zone microorganisms.

  2. Radio frequency heating for soil remediation

    SciTech Connect

    Price, S.L.; Kasevich, R.S.; Marley, M.C.

    1997-12-31

    Radio frequency heating (RFH) for soil remediation brings controlled heating to the subsurface, increasing the rate of removal of contaminants from the soil. RFH alone does not remove contaminants; it eases contaminant removal by enhancing the performance of other technologies such as Soil Vapor Extraction (SVE), Groundwater Venting (Air Sparging), Groundwater Pump and Treat, and Bioremediation. In general, heating soils and groundwater makes the physical, chemical and biological properties of the soil, groundwater and contaminants more amenable to remediation efforts, reducing time on-site. RFH technology for environmental remediation by KAI Technologies Inc. (KAI) began in the early 1990s when an RFH system was deployed to an East Coast Naval Shipyard and tested on a {number_sign}2 fuel oil spill. RFH was then employed by KAI at the Department of Energy`s Savannah River Site (SRS) in 1993 and at Kelly Air Force Base in 1994. This paper discusses the spring 1996 RFH demonstration conducted with DAHL and Associates of St. Paul, Minnesota which employed SVE and Groundwater Venting at the site of a former gasoline station near St. Paul, Minnesota. Currently, RFH is assisting SVE at a jet fuel spill within Kirtland Air Force Base in Albuquerque, New Mexico. This paper provides a general overview of RFH technology for soil remediation by reviewing the theory and computer modeling of RFH and presenting results on the efficacy of RFH with SVE for soil remediation from a bench-scale study and the field demonstration mentioned previously. The bench-scale study evaluated effectiveness of RFH for enhancing SVE removal of tetrachloroethylene from a Burlington, Massachusetts site. Data from Finite-Difference Time Domain (FDTD) computer modeling of the field demonstration provides insight into the shape of the subsurface heating pattern.

  3. DESIGN OF A SURFACTANT REMEDIATION FIELD DEMONSTRATION BASED ON LABORATORY AND MODELINE STUDIES

    EPA Science Inventory

    Surfactant-enhanced subsurface remediation is being evaluated as an innovative technology for expediting ground-water remediation. This paper reports on laboratory and modeling studies conducted in preparation for a pilot-scale field test of surfactant-enhanced subsurface remedia...

  4. Recombination Enhances HIV-1 Envelope Diversity by Facilitating the Survival of Latent Genomic Fragments in the Plasma Virus Population.

    PubMed

    Immonen, Taina T; Conway, Jessica M; Romero-Severson, Ethan O; Perelson, Alan S; Leitner, Thomas

    2015-12-01

    HIV-1 is subject to immune pressure exerted by the host, giving variants that escape the immune response an advantage. Virus released from activated latent cells competes against variants that have continually evolved and adapted to host immune pressure. Nevertheless, there is increasing evidence that virus displaying a signal of latency survives in patient plasma despite having reduced fitness due to long-term immune memory. We investigated the survival of virus with latent envelope genomic fragments by simulating within-host HIV-1 sequence evolution and the cycling of viral lineages in and out of the latent reservoir. Our model incorporates a detailed mutation process including nucleotide substitution, recombination, latent reservoir dynamics, diversifying selection pressure driven by the immune response, and purifying selection pressure asserted by deleterious mutations. We evaluated the ability of our model to capture sequence evolution in vivo by comparing our simulated sequences to HIV-1 envelope sequence data from 16 HIV-infected untreated patients. Empirical sequence divergence and diversity measures were qualitatively and quantitatively similar to those of our simulated HIV-1 populations, suggesting that our model invokes realistic trends of HIV-1 genetic evolution. Moreover, reconstructed phylogenies of simulated and patient HIV-1 populations showed similar topological structures. Our simulation results suggest that recombination is a key mechanism facilitating the persistence of virus with latent envelope genomic fragments in the productively infected cell population. Recombination increased the survival probability of latent virus forms approximately 13-fold. Prevalence of virus with latent fragments in productively infected cells was observed in only 2% of simulations when we ignored recombination, while the proportion increased to 27% of simulations when we allowed recombination. We also found that the selection pressures exerted by different fitness

  5. Recombination enhances HIV-1 envelope diversity by facilitating the survival of latent genomic fragments in the plasma virus population

    SciTech Connect

    Immonen, Taina T.; Conway, Jessica M.; Romero-Severson, Ethan O.; Perelson, Alan S.; Leitner, Thomas; Kouyos, Roger Dimitri

    2015-12-22

    HIV-1 is subject to immune pressure exerted by the host, giving variants that escape the immune response an advantage. Virus released from activated latent cells competes against variants that have continually evolved and adapted to host immune pressure. Nevertheless, there is increasing evidence that virus displaying a signal of latency survives in patient plasma despite having reduced fitness due to long-term immune memory. We investigated the survival of virus with latent envelope genomic fragments by simulating within-host HIV-1 sequence evolution and the cycling of viral lineages in and out of the latent reservoir. Our model incorporates a detailed mutation process including nucleotide substitution, recombination, latent reservoir dynamics, diversifying selection pressure driven by the immune response, and purifying selection pressure asserted by deleterious mutations. We evaluated the ability of our model to capture sequence evolution in vivo by comparing our simulated sequences to HIV-1 envelope sequence data from 16 HIV-infected untreated patients. Empirical sequence divergence and diversity measures were qualitatively and quantitatively similar to those of our simulated HIV-1 populations, suggesting that our model invokes realistic trends of HIV-1 genetic evolution. Moreover, reconstructed phylogenies of simulated and patient HIV-1 populations showed similar topological structures. Our simulation results suggest that recombination is a key mechanism facilitating the persistence of virus with latent envelope genomic fragments in the productively infected cell population. Recombination increased the survival probability of latent virus forms approximately 13-fold. Prevalence of virus with latent fragments in productively infected cells was observed in only 2% of simulations when we ignored recombination, while the proportion increased to 27% of simulations when we allowed recombination. We also found that the selection pressures exerted by different fitness

  6. Remediation technologies for contaminated sediments

    SciTech Connect

    Swanson, L.M.

    1995-09-01

    Although soil and groundwater remediation has been conducted for many years, sediment remediation is still in its infancy. Regulatory agencies are now beginning to identify areas where contaminated sediments exist and evaluate their environmental impact. As these evaluations are completed, the projects must shift focus to how these sediments can be remediated. Also as the criteria for aquatic disposal of dredged sediments become more stringent, remediation technologies must be developed to address contaminated sediments generated by maintenance dredging.This report describes the various issues and possible technologies for sediment remediation.

  7. Stock enhancement or sea ranching? Insights from monitoring the genetic diversity, relatedness and effective population size in a seeded great scallop population (Pecten maximus).

    PubMed

    Morvezen, R; Boudry, P; Laroche, J; Charrier, G

    2016-09-01

    The mass release of hatchery-propagated stocks raises numerous questions concerning its efficiency in terms of local recruitment and effect on the genetic diversity of wild populations. A seeding program, consisting of mass release of hatchery-produced juveniles in the local naturally occurring population of great scallops (Pecten maximus L.), was initiated in the early 1980s in the Bay of Brest (France). The present study aims at evaluating whether this seeding program leads to actual population enhancement, with detectable effects on genetic diversity and effective population size, or consists of sea ranching with limited genetic consequences on the wild stock. To address this question, microsatellite-based genetic monitoring of three hatchery-born and naturally recruited populations was conducted over a 5-year period. Results showed a limited reduction in allelic richness but a strong alteration of allelic frequencies in hatchery populations, while genetic diversity appeared very stable over time in the wild populations. A temporal increase in relatedness was observed in both cultured stock and wild populations. Effective population size (Ne) estimates were low and variable in the wild population. Moreover, the application of the Ryman-Laikre model suggested a high contribution of hatchery-born scallops to the reproductive output of the wild population. Overall, the data suggest that the main objective of the seeding program, which is stock enhancement, is fulfilled. Moreover, gene flow from surrounding populations and/or the reproductive input of undetected sub-populations within the bay may buffer the Ryman-Laikre effect and ensure the retention of the local genetic variability.

  8. Enhancing Diversity In The Geosciences; Intensive Field Experience In USA And Mexico For Middle And High School Teachers Serving Large Hispanic Populations.

    NASA Astrophysics Data System (ADS)

    Leal-Bautista, R. M.; Kitts, K. B.; Velazquez Oliman, G.; Perry, E. C.

    2008-12-01

    To encourage Hispanic participation and enrolment in the geosciences and ultimately enhance diversity within the discipline, we recruited ten middle and high school science teachers serving large Hispanic populations (60-97%) for a paid three-week field experience supported by an NSF Opportunities for Enhancing Diversity in the Geosciences grant. In 2006, the field experiences focused on volcanic events and the water problems of the Central part of Mexico. In 2008, the field experiences focused on karstic and hydrogeological conditions of the Yucatan Peninsula. In addition to the geological aspects of the fieldwork experience, the trip to Mexico exposed the teachers to a social environment outside of their community where they interacted with a diverse group of scientists from the Universidad National Autonoma de Mexico (UNAM), Centro de Investigacion Cientifica de Yucatan (CICY) and Centro Nacional de Desastres (CENAPRED). A key part of this project was the encounter between American and Mexican teachers that included a day of presentations, panel discussion and some class-room activities. Direct interaction between the cooperating teachers and the American and Mexican geoscientists provided actual scientific research experiences to educate and to help dispel misconceptions the teachers themselves may have had about who geoscientists really are and what they do. Teachers of the 2006 group produced educational materials from their field experiences and presented these materials at professional conferences. We measured the efficacy of these activities quantitatively via pre- and post-tests assessing confidence levels, preconceptions and biases, NIU staff observations of participants in their home institutions, and evaluations of participants' field books and pedagogical materials. We present these data here and identify specific activities that are both effective and efficient in changing teacher behaviours and attitudes enabling them to better connect with their

  9. [Rhizosphere enhanced remediation of petroleum contaminated soil].

    PubMed

    Lu, Mang; Zhang, Zhong-zhi; Sun, Shan-shan; Qiao, Wei; Liu, Xiao

    2009-12-01

    The effects of growing tall fescue on the biodegradation of hydrocarbons was studied in laboratory scale pots. Degradation of hydrocarbons as well as microbial counts, soil fluorescein diacetate activity, catalase activity and dehydrogenase activity were determined. The results showed that, in the rhizosphere soil system, total petroleum hydrocarbons disappeared faster than that in unvegetated pots soil. After 10 weeks, 11.8% and 27.4% of spiked petroleum hydrocarbons disappeared from the bulk and rhizosphere soils respectively. Abiotic loss of petroleum hydrocarbons by evaporation was of minor significance in the test. The microbial plate counts and soil enzyme activities were significantly higher in the rhizosphere than in the bulk soil. Petroleum compounds had significant effect on fluorescein diacetate hydrolyzing activity. Vegetation resulted in significantly greater first-order decay constants compared to the unvegetated control. Oxygenated polycyclic aromatic hydrocarbons that were present in the soil were generally degraded more slowly than the parent compounds, suggesting that they were formed during the treatment or that they are more persistent. Four oxidation products of polycyclic aromatic hydrocarbons, 1-acenaphthenone, 9-fluorenone, anthraquinone, and benzfluorenone were found at significantly higher concentrations at the end of the study.

  10. Understanding and enhancing the learning experiences of culturally and linguistically diverse nursing students in an Australian bachelor of nursing program.

    PubMed

    Jeong, Sarah Yeun-Sim; Hickey, Noelene; Levett-Jones, Tracy; Pitt, Victoria; Hoffman, Kerry; Norton, Carol Anne; Ohr, Se Ok

    2011-04-01

    The growth in numbers of culturally and linguistically diverse students entering nursing programs in Australia presents challenges for academic and clinical staff, and most importantly the students themselves. In this paper we present the findings from a pilot study designed to explore these issues and to develop strategies to address them. This study used a qualitative explorative approach to gain rich in-depth data. Eleven culturally and linguistically diverse students, three clinical facilitators, and four academic staff participated in focus group interviews. Four major themes emerged: level of English language competence, feelings of isolation, limited opportunities for learning, and inadequate university support. The issues we identified led to a meaningful discussion of the political, financial, social and intercultural context that they are entrapped in. This paper provides educators, clinicians, policy makers and researchers with an insight where and how they commence to break the trap and highlights, the need for further research into the perspectives of Australian students' who study and socialise with their international peers.

  11. Understanding and enhancing the learning experiences of culturally and linguistically diverse nursing students in an Australian bachelor of nursing program.

    PubMed

    Jeong, Sarah Yeun-Sim; Hickey, Noelene; Levett-Jones, Tracy; Pitt, Victoria; Hoffman, Kerry; Norton, Carol Anne; Ohr, Se Ok

    2011-04-01

    The growth in numbers of culturally and linguistically diverse students entering nursing programs in Australia presents challenges for academic and clinical staff, and most importantly the students themselves. In this paper we present the findings from a pilot study designed to explore these issues and to develop strategies to address them. This study used a qualitative explorative approach to gain rich in-depth data. Eleven culturally and linguistically diverse students, three clinical facilitators, and four academic staff participated in focus group interviews. Four major themes emerged: level of English language competence, feelings of isolation, limited opportunities for learning, and inadequate university support. The issues we identified led to a meaningful discussion of the political, financial, social and intercultural context that they are entrapped in. This paper provides educators, clinicians, policy makers and researchers with an insight where and how they commence to break the trap and highlights, the need for further research into the perspectives of Australian students' who study and socialise with their international peers. PMID:21078536

  12. Rhizosphere competent Pantoea agglomerans enhances maize (Zea mays) and chickpea (Cicer arietinum L.) growth, without altering the rhizosphere functional diversity.

    PubMed

    Mishra, Aradhana; Chauhan, Puneet Singh; Chaudhry, Vasvi; Tripathi, Manisha; Nautiyal, Chandra Shekhar

    2011-10-01

    Plant growth promoting Pantoea agglomerans NBRISRM (NBRISRM) was able to produce 60.4 μg/ml indole acetic acid and solubilize 77.5 μg/ml tri-calcium phosphate under in vitro conditions. Addition of 2% NaCl (w/v) in the media induced the IAA production and phosphate solubilization by 11% and 7%, respectively. For evaluating the plant growth promotory effect of NBRISRM inoculation a micro plot trial was conducted using maize and chickpea as host plants. The results revealed significant increase in all growth parameters tested in NBRISRM inoculated maize and chickpea plants, which were further confirmed by higher macronutrients (N, P and K) accumulation as compared to un-inoculated controls. Throughout the growing season of maize and chickpea, rhizosphere population of NBRISRM were in the range 10(7)-10(8) CFU/g soil and competing with 10(7)-10(9) CFU/g soil with heterogeneous bacterial population. Functional richness, diversity, and evenness were found significantly higher in maize rhizosphere as compared to chickpea, whereas NBRISRM inoculation were not able to change it, in both crops as compared to their un-inoculated control. To the best of our knowledge this is first report where we demonstrated the effect of P. agglomerans strain for improving maize and chickpea growth without altering the functional diversity.

  13. Vaporization or Chemical Reaction: Which controls the fate of contaminants treated by in situ thermal remediation?

    EPA Science Inventory

    Thermal remediation technologies, which includes steam enhanced extraction, electrical resistance heating, and thermal conductive heating, have been developed based on technologies employed by the enhanced oil recovery industry. Although mobilization and/or volatilization of con...

  14. Remediation Technology Collaboration Development

    NASA Technical Reports Server (NTRS)

    Mahoney, John; Olsen, Wade

    2010-01-01

    This slide presentation reviews programs at NASA aimed at development at Remediation Technology development for removal of environmental pollutants from NASA sites. This is challenging because there are many sites with different environments, and various jurisdictions and regulations. There are also multiple contaminants. There must be different approaches based on location and type of contamination. There are other challenges: such as costs, increased need for resources and the amount of resources available, and a regulatory environment that is increasing.

  15. Remediating munitions contaminated soils

    SciTech Connect

    Shea, P.J.; Comfort, S.D.

    1995-10-01

    The former Nebraska Ordnance Plant (NOP) at Mead, NE was a military loading, assembling, and packing facility that produced bombs, boosters and shells during World War II and the Korean War (1942-1945, 1950-1956). Ordnances were loaded with 2,4,6-trinitrotoluene (TNT), amatol (TNT and NH{sub 4}NO{sub 3}), tritonal (TNT and Al) and Composition B (hexahydro-1,3,5-trinitro-1,3,5-triazine [RDX] and TNT). Process waste waters were discharged into wash pits and drainage ditches. Soils within and surrounding these areas are contaminated with TNT, RDX and related compounds. A continuous core to 300 cm depth obtained from an NOP drainage ditch revealed high concentrations of TNT in the soil profile and substantial amounts of monoamino reduction products, 4-amino-2,6-dinitrotoluene (4ADNT) and 2-amino-4,6-dinitrotoluene (2ADNT). Surface soil contained TNT in excess of 5000 mg kg{sup -1} and is believed to contain solid phase TNT. This is supported by measuring soil solution concentrations at various soil to solution ratios (1:2 to 1:9) and obtaining similar TNT concentrations (43 and 80 mg L{sup -1}). Remediating munitions-contaminated soil at the NOP and elsewhere is of vital interest since many of the contaminants are carcinogenic, mutagenic or otherwise toxic to humans and the environment. Incineration, the most demonstrated remediation technology for munitions-containing soils, is costly and often unacceptable to the public. Chemical and biological remediation offer potentially cost-effective and more environmentally acceptable alternatives. Our research objectives are to: (a) characterize the processes affecting the transport and fate of munitions in highly contaminated soil; (b) identify effective chemical and biological treatments to degrade and detoxify residues; and (c) integrate these approaches for effective and practical remediation of soil contaminated with TNT, RDX, and other munitions residues.

  16. Recombination enhances HIV-1 envelope diversity by facilitating the survival of latent genomic fragments in the plasma virus population

    DOE PAGESBeta

    Immonen, Taina T.; Conway, Jessica M.; Romero-Severson, Ethan O.; Perelson, Alan S.; Leitner, Thomas; Kouyos, Roger Dimitri

    2015-12-22

    HIV-1 is subject to immune pressure exerted by the host, giving variants that escape the immune response an advantage. Virus released from activated latent cells competes against variants that have continually evolved and adapted to host immune pressure. Nevertheless, there is increasing evidence that virus displaying a signal of latency survives in patient plasma despite having reduced fitness due to long-term immune memory. We investigated the survival of virus with latent envelope genomic fragments by simulating within-host HIV-1 sequence evolution and the cycling of viral lineages in and out of the latent reservoir. Our model incorporates a detailed mutation processmore » including nucleotide substitution, recombination, latent reservoir dynamics, diversifying selection pressure driven by the immune response, and purifying selection pressure asserted by deleterious mutations. We evaluated the ability of our model to capture sequence evolution in vivo by comparing our simulated sequences to HIV-1 envelope sequence data from 16 HIV-infected untreated patients. Empirical sequence divergence and diversity measures were qualitatively and quantitatively similar to those of our simulated HIV-1 populations, suggesting that our model invokes realistic trends of HIV-1 genetic evolution. Moreover, reconstructed phylogenies of simulated and patient HIV-1 populations showed similar topological structures. Our simulation results suggest that recombination is a key mechanism facilitating the persistence of virus with latent envelope genomic fragments in the productively infected cell population. Recombination increased the survival probability of latent virus forms approximately 13-fold. Prevalence of virus with latent fragments in productively infected cells was observed in only 2% of simulations when we ignored recombination, while the proportion increased to 27% of simulations when we allowed recombination. We also found that the selection pressures exerted by different

  17. Environmental impacts of remediation of a trichloroethene-contaminated site: life cycle assessment of remediation alternatives.

    PubMed

    Lemming, Gitte; Hauschild, Michael Z; Chambon, Julie; Binning, Philip J; Bulle, Cécile; Margni, Manuele; Bjerg, Poul L

    2010-12-01

    The environmental impacts of remediation of a chloroethene-contaminated site were evaluated using life cycle assessment (LCA). The compared remediation options are (i) in situ bioremediation by enhanced reductive dechlorination (ERD), (ii) in situ thermal desorption (ISTD), and (iii) excavation of the contaminated soil followed by off-site treatment and disposal. The results showed that choosing the ERD option will reduce the life-cycle impacts of remediation remarkably compared to choosing either ISTD or excavation, which are more energy-demanding. In addition to the secondary impacts of remediation, this study includes assessment of local toxic impacts (the primary impact) related to the on-site contaminant leaching to groundwater and subsequent human exposure via drinking water. The primary human toxic impacts were high for ERD due to the formation and leaching of chlorinated degradation products, especially vinyl chloride during remediation. However, the secondary human toxic impacts of ISTD and excavation are likely to be even higher, particularly due to upstream impacts from steel production. The newly launched model, USEtox, was applied for characterization of primary and secondary toxic impacts and combined with a site-dependent fate model of the leaching of chlorinated ethenes from the fractured clay till site.

  18. Remediating MGP brownfields

    SciTech Connect

    Larsen, B.R.

    1997-05-01

    Before natural gas pipelines became widespread in this country, gas fuel was produced locally in more than 5,000 manufactured gas plants (MGPs). The toxic wastes from these processes often were disposed onsite and have since seeped into the surrounding soil and groundwater. Although the MGPs--commonly called gas plants, gas-works or town gas plants--have closed and most have been demolished, they have left a legacy of environmental contamination. At many MGP sites, underground storage tanks were constructed of wood or brick, with process piping and equipment which frequently leaked. Waste materials often were disposed onsite. Releases of coal tars, oils and condensates produced within the plants contributed to a wide range of contamination from polycyclic aromatic hydrocarbons, phenols, benzene and cyanide. Remediation of selected MGP sites has been sporadic. Unless the site has been identified as a Comprehensive Environmental Response, Compensation and Liability Information System (CERCLIS) Superfund site, the regulatory initiative to remediate often remains with the state in which the MGP is located. A number of factors are working to change that picture and to create a renewed interest in MGP site remediation. The recent Brownfield Initiative by the US Environmental Protection Agency (EPA) is such an example.

  19. Remedial Action Assessment System

    1997-02-01

    RAAS1.1 is a software-based system designed to assist remediation professionals at each stage of the environmental analysis process. RAAS1.1 provides a template for environmental restoration analysis, and provides the user with key results at each step in the analysis. RAAS1.1 assists the user to develop a coherent and consistent site description, estimate baseline and residual risk to public health from the contaminated site, identify applicable environmental restoration technologies, and formulate feasible remedial response alternatives. Inmore » addition, the RAAS1.1 methodology allows the user to then assess and compare those remedial response alternatives across EPA criteria, including: compliance with objectives; short-term and long-term effectiveness; extent of treatment; and implementability of the technologies. The analytic methodology is segmented and presented in a standardized, concise, easy-to-use format that can be viewed on the personal computer screen, saved and further manipulated, or printed for later use. Each screen and analytic step is accessed via a user-friendly personal computer graphical interface. Intuitively-designed buttons, menus, and lists help the user focus in on the particular information and analysis component of interest; the corresponding results are presented in a format that facilitates their use in decision-making.« less

  20. IN-SITU THERMAL REMEDIATION: MECHANISMS, PRINCIPLES, AND CASE STUDIES

    EPA Science Inventory

    Since the early 1990's, thermal methods of enhanced oil recovery have been adapted for the remediation of soils and groundwater. Steam injection and electrical resistance heating have proven to be robust and aggressive techniques for the enhanced recovery of volatile and semivol...

  1. Remediation of Uranium Impacted Sediments in a Watercourse - 12486

    SciTech Connect

    Shephard, E.; Walter, N.; Downey, H.; Collopy, P.; Conant, J.

    2012-07-01

    In 2009, remediation was initiated for a non-operational fuel cycle facility previously used for government contract work. Between 2009 and the spring of 2011, remediation efforts were focused on demolition of contaminated buildings and removal of contaminated soil. In the late spring of 2011, the last phase of remediation commenced involving the removal of contaminated sediments from portions of a 1,200 meter long gaining stream. Planning and preparation for remediation of the stream began in 2009 with submittal of permit applications to undertake construction activities in a wetland area. The permitting process was lengthy and involved securing permits from multiple agencies. However, early and frequent communication with stakeholders played an integral role in efficiently obtaining the permit approvals. Frequent communication with stakeholders throughout the planning and remediation process also proved to be a key factor in timely completion of the project. The remediation of the stream involved the use of temporary bladder berms to divert surface water flow, water diversion piping, a sediment vacuum removal system, excavation of sediments using small front-end loaders, sediment dewatering, and waste packaging, transportation and disposal. Many safeguards were employed to protect several species of concern in the work area, water management during project activities, challenges encountered during the project, methods of Final Status Survey, and stream restoration. The planning and permitting effort for the Site Brook remediation began in May 2009 and permits were approved and in place by February 2011. The remediation and restoration of the Site Brook began in April 2011 and was completed in November 2011. The remediation of the Site Brook involved the use of temporary bladder berms to divert surface water flow, water diversion piping, a sediment vacuum removal system, excavation of sediments using small front-end loaders, sediment dewatering, and waste

  2. Novel sorbents for environmental remediation

    NASA Astrophysics Data System (ADS)

    Manariotis, Ioannis D.; Karapanagioti, Hrissi K.; Werner, David

    2014-05-01

    Nowadays, one of the major environmental problems is the pollution of aquatic systems and soil by persistent pollutants. Persistent pollutants have been found widespread in sediments, surface waters, and drinking water supplies. The removal of pollutants can be accomplished prior to their discharge to receiving bodies or by immobilizing them onto soil. Sorption is the most commonly applied process, and activated carbons have been widely used. Rapid progress in nanotechnology and a new focus on biomass-based instead of non-renewable starting materials have produced a wide range of novel engineered sorbents including biosorbents, biochars, carbon-based nanoparticles, bio-nano hybrid materials, and iron-impregnated activated carbons. Sorbent materials have been used in environmental remediation processes and especially in agricultural soil, sediments and contaminated soil, water treatment, and industrial wastewater treatment. Furthermore, sorbents may enhance the synergistic action of other processes, such as volatilization and biodegradation. Novel sorbents have been employed for the removal or immobilization of persistent pollutants such as and include heavy metals (As, Cr, Cu, Pb, Cd, and Hg), halogenated organic compounds, endocrine disrupting chemicals, metalloids and non-metallic elements, and other organic pollutants. The development and evaluation of novel sorbents requires a multidisciplinary approach encompassing environmental, nanotechnology, physical, analytical, and surface chemistry. The necessary evaluations encompass not only the efficiency of these materials to remove pollutants from surface waters and groundwater, industrial wastewater, polluted soils and sediments, etc., but also the potential side-effects of their environmental applications. The aim of this work is to present the results of the use of biochar and impregnated carbon sorbents for the removal of organic pollutants and metals. Furthermore, the new findings from the forthcoming session

  3. The Geoscience Diversity Enhancement Program (GDEP): A Model for Faculty and Student Engagement in Urban Geoscience Research

    NASA Astrophysics Data System (ADS)

    Ambos, E. L.; Lee, C.; Behl, R.; Francis, R. D.; Holk, G.; Larson, D.; Rodrigue, C.; Wechsler, S.; Whitney, D.

    2004-12-01

    For the past three years (2002-2004) faculty in the departments of geological sciences, geography, and anthropology at California State University, Long Beach have joined to offer an NSF-funded (GEO-0119891) eight-week summer research experience to faculty and students at Long Beach area high schools and community colleges. GDEP's goal is to increase the numbers of students from underrepresented groups (African-American, Hispanic, American Indian, Pacific Islander, and disabled) enrolling in baccalaureate degree programs in the geosciences. The major strategies to achieve this goal all tie to the concept of research-centered experiences, which might also be termed inquiry-based instruction. More than fifteen (15) separate and diverse geoscience research studies have been conducted. These include such disparate topics as geochemical studies of fault veins, GPS/GIS surveys of vegetation patterns for fire hazard assessment, and seismic studies of offshore fault systems. As the program has matured, research projects have become more interdisciplinary, and faculty research teams have expanded. Whereas the first year, each CSULB faculty member tended to lead her/his project as a separate endeavor, by the third summer, faculty were collaborating in research teams. Several projects have involved community-based research, at sites within an hour's drive from the urban Long Beach campus. For example, last summer, four faculty linked together to conduct a comprehensive geography and geology study of an Orange County wilderness area, resulting in creation of maps, brochures, and websites for use by the general public. Another faculty group conducted geophysical surveys at an historic archaeological site in downtown Los Angeles, producing maps of underground features that will be incorporated into a cultural center and museum. Over the past three summers, the program has grown to involve more than 25 high school and community college students, and more than 30 CSULB, high

  4. Enhancing Genome-Wide Copy Number Variation Identification by High Density Array CGH Using Diverse Resources of Pig Breeds

    PubMed Central

    Wang, Jiying; Jiang, Jicai; Wang, Haifei; Kang, Huimin; Zhang, Qin; Liu, Jian-Feng

    2014-01-01

    Copy number variations (CNVs) are important forms of genomic variation, and have attracted extensive attentions in humans as well as domestic animals. In the study, using a custom-designed 2.1 M array comparative genomic hybridization (aCGH), genome-wide CNVs were identified among 12 individuals from diverse pig breeds, including one Asian wild population, six Chinese indigenous breeds and two modern commercial breeds (Yorkshire and Landrace), with one individual of the other modern commercial breed, Duroc, as the reference. A total of 1,344 CNV regions (CNVRs) were identified, covering 47.79 Mb (∼1.70%) of the pig genome. The length of these CNVRs ranged from 3.37 Kb to 1,319.0 Kb with a mean of 35.56 Kb and a median of 11.11 Kb. Compared with similar studies reported, most of the CNVRs (74.18%) were firstly identified in present study. In order to confirm these CNVRs, 21 CNVRs were randomly chosen to be validated by quantitative real time PCR (qPCR) and a high rate (85.71%) of confirmation was obtained. Functional annotation of CNVRs suggested that the identified CNVRs have important function, and may play an important role in phenotypic and production traits difference among various breeds. Our results are essential complementary to the CNV map in the pig genome, which will provide abundant genetic markers to investigate association studies between various phenotypes and CNVs in pigs. PMID:24475311

  5. Structural Diversity of Ligand-Binding Androgen Receptors Revealed by Microsecond Long Molecular Dynamics Simulations and Enhanced Sampling.

    PubMed

    Duan, Mojie; Liu, Na; Zhou, Wenfang; Li, Dan; Yang, Minghui; Hou, Tingjun

    2016-09-13

    Androgen receptor (AR) plays important roles in the development of prostate cancer (PCa). The antagonistic drugs, which suppress the activity of AR, are widely used in the treatment of PCa. However, the molecular mechanism of antagonism about how ligands affect the structures of AR remains elusive. To better understand the conformational variability of ARs bound with agonists or antagonists, we performed long time unbiased molecular dynamics (MD) simulations and enhanced sampling simulations for the ligand binding domain of AR (AR-LBD) in complex with various ligands. Based on the simulation results, we proposed an allosteric pathway linking ligands and helix 12 (H12) of AR-LBD, which involves the interactions among the ligands and the residues W741, H874, and I899. The interaction pathway provides an atomistic explanation of how ligands affect the structure of AR-LBD. A repositioning of H12 was observed, but it is facilitated by the C-terminal of H12, instead of by the loop between helix 11 (H11) and H12. The bias-exchange metadynamics simulations further demonstrated the above observations. More importantly, the free energy profiles constructed by the enhanced sampling simulations revealed the transition process between the antagonistic form and agonistic form of AR-LBD. Our results would be helpful for the design of more efficient antagonists of AR to combat PCa. PMID:27560203

  6. Physiochemical technologies for HCB remediation and disposal: a review.

    PubMed

    Tong, Man; Yuan, Songhu

    2012-08-30

    Hexachlorobenzene (HCB) is one of the 12 persistent organic pollutants (POPs) listed in "Stockholm Convention". It is hydrophobic, toxic and persistent in the environment. Due to extensive use in the past, HCB contamination is still a serious environmental problem. Strong adsorption on solid particles makes the remediation difficult. This paper presents an overview of the physiochemical technologies for HCB remediation and disposal. The adsorption/desorption behavior of HCB is firstly described because it comprises the fundamental for most remediation technologies. Physiochemical technologies concerned mostly for HCB remediation and disposal, i.e., chemical enhanced washing, electrokinetic remediation, reductive dechlorination and thermal decomposition, are reviewed in terms of fundamentals, state of the art and perspectives. The other physiochemical technologies including chemical oxidation, radiation induced catalytic dechlorination, ultrasonic assisted treatment and mechanochemical dechlorination are also reviewed. The pilot and large scale tests on HCB remediation or disposal are summarized in the end. This review aims to provide useful information to researchers and practitioners regarding HCB remediation and disposal. PMID:22709849

  7. Harnessing Diversity in Wheat to Enhance Grain Yield, Climate Resilience, Disease and Insect Pest Resistance and Nutrition Through Conventional and Modern Breeding Approaches.

    PubMed

    Mondal, Suchismita; Rutkoski, Jessica E; Velu, Govindan; Singh, Pawan K; Crespo-Herrera, Leonardo A; Guzmán, Carlos; Bhavani, Sridhar; Lan, Caixia; He, Xinyao; Singh, Ravi P

    2016-01-01

    Current trends in population growth and consumption patterns continue to increase the demand for wheat, a key cereal for global food security. Further, multiple abiotic challenges due to climate change and evolving pathogen and pests pose a major concern for increasing wheat production globally. Triticeae species comprising of primary, secondary, and tertiary gene pools represent a rich source of genetic diversity in wheat. The conventional breeding strategies of direct hybridization, backcrossing and selection have successfully introgressed a number of desirable traits associated with grain yield, adaptation to abiotic stresses, disease resistance, and bio-fortification of wheat varieties. However, it is time consuming to incorporate genes conferring tolerance/resistance to multiple stresses in a single wheat variety by conventional approaches due to limitations in screening methods and the lower probabilities of combining desirable alleles. Efforts on developing innovative breeding strategies, novel tools and utilizing genetic diversity for new genes/alleles are essential to improve productivity, reduce vulnerability to diseases and pests and enhance nutritional quality. New technologies of high-throughput phenotyping, genome sequencing and genomic selection are promising approaches to maximize progeny screening and selection to accelerate the genetic gains in breeding more productive varieties. Use of cisgenic techniques to transfer beneficial alleles and their combinations within related species also offer great promise especially to achieve durable rust resistance. PMID:27458472

  8. Harnessing Diversity in Wheat to Enhance Grain Yield, Climate Resilience, Disease and Insect Pest Resistance and Nutrition Through Conventional and Modern Breeding Approaches

    PubMed Central

    Mondal, Suchismita; Rutkoski, Jessica E.; Velu, Govindan; Singh, Pawan K.; Crespo-Herrera, Leonardo A.; Guzmán, Carlos; Bhavani, Sridhar; Lan, Caixia; He, Xinyao; Singh, Ravi P.

    2016-01-01

    Current trends in population growth and consumption patterns continue to increase the demand for wheat, a key cereal for global food security. Further, multiple abiotic challenges due to climate change and evolving pathogen and pests pose a major concern for increasing wheat production globally. Triticeae species comprising of primary, secondary, and tertiary gene pools represent a rich source of genetic diversity in wheat. The conventional breeding strategies of direct hybridization, backcrossing and selection have successfully introgressed a number of desirable traits associated with grain yield, adaptation to abiotic stresses, disease resistance, and bio-fortification of wheat varieties. However, it is time consuming to incorporate genes conferring tolerance/resistance to multiple stresses in a single wheat variety by conventional approaches due to limitations in screening methods and the lower probabilities of combining desirable alleles. Efforts on developing innovative breeding strategies, novel tools and utilizing genetic diversity for new genes/alleles are essential to improve productivity, reduce vulnerability to diseases and pests and enhance nutritional quality. New technologies of high-throughput phenotyping, genome sequencing and genomic selection are promising approaches to maximize progeny screening and selection to accelerate the genetic gains in breeding more productive varieties. Use of cisgenic techniques to transfer beneficial alleles and their combinations within related species also offer great promise especially to achieve durable rust resistance. PMID:27458472

  9. Harnessing Diversity in Wheat to Enhance Grain Yield, Climate Resilience, Disease and Insect Pest Resistance and Nutrition Through Conventional and Modern Breeding Approaches.

    PubMed

    Mondal, Suchismita; Rutkoski, Jessica E; Velu, Govindan; Singh, Pawan K; Crespo-Herrera, Leonardo A; Guzmán, Carlos; Bhavani, Sridhar; Lan, Caixia; He, Xinyao; Singh, Ravi P

    2016-01-01

    Current trends in population growth and consumption patterns continue to increase the demand for wheat, a key cereal for global food security. Further, multiple abiotic challenges due to climate change and evolving pathogen and pests pose a major concern for increasing wheat production globally. Triticeae species comprising of primary, secondary, and tertiary gene pools represent a rich source of genetic diversity in wheat. The conventional breeding strategies of direct hybridization, backcrossing and selection have successfully introgressed a number of desirable traits associated with grain yield, adaptation to abiotic stresses, disease resistance, and bio-fortification of wheat varieties. However, it is time consuming to incorporate genes conferring tolerance/resistance to multiple stresses in a single wheat variety by conventional approaches due to limitations in screening methods and the lower probabilities of combining desirable alleles. Efforts on developing innovative breeding strategies, novel tools and utilizing genetic diversity for new genes/alleles are essential to improve productivity, reduce vulnerability to diseases and pests and enhance nutritional quality. New technologies of high-throughput phenotyping, genome sequencing and genomic selection are promising approaches to maximize progeny screening and selection to accelerate the genetic gains in breeding more productive varieties. Use of cisgenic techniques to transfer beneficial alleles and their combinations within related species also offer great promise especially to achieve durable rust resistance.

  10. Integrated in-situ remediation

    SciTech Connect

    Fustos, V.; Lieberman, P.

    1996-01-01

    This article presents an integrated approach to ex-situ and in-situ remediation. A sequence of processes, used successfully in their own right, but used synergistically in this approach, have achieved short-term, economic remediation. In addition the range of contaminants that can be treated is extended. The Process uses ozone, compressed oxygen, water vapor, heat, bioaugmentation and vapor extraction to remediate lower molecular weight hydrocarbons and higher molecular weight hydrocarbons. 3 figs.

  11. CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY

    SciTech Connect

    BERGMAN, T. B.; STEFANSKI, L. D.; SEELEY, P. N.; ZINSLI, L. C.; CUSACK, L. J.

    2012-09-19

    THE CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY WAS CONDUCTED TO DEVELOP AN OPTIMAL SEQUENCE OF REMEDIATION ACTIVITIES IMPLEMENTING THE CERCLA DECISION ON THE CENTRAL PLATEAU. THE STUDY DEFINES A SEQUENCE OF ACTIVITIES THAT RESULT IN AN EFFECTIVE USE OF RESOURCES FROM A STRATEGIC PERSPECTIVE WHEN CONSIDERING EQUIPMENT PROCUREMENT AND STAGING, WORKFORCE MOBILIZATION/DEMOBILIZATION, WORKFORCE LEVELING, WORKFORCE SKILL-MIX, AND OTHER REMEDIATION/DISPOSITION PROJECT EXECUTION PARAMETERS.

  12. Electrokinetic remediation prefield test methods

    NASA Technical Reports Server (NTRS)

    Hodko, Dalibor (Inventor)

    2000-01-01

    Methods for determining the parameters critical in designing an electrokinetic soil remediation process including electrode well spacing, operating current/voltage, electroosmotic flow rate, electrode well wall design, and amount of buffering or neutralizing solution needed in the electrode wells at operating conditions are disclosed These methods are preferably performed prior to initiating a full scale electrokinetic remediation process in order to obtain efficient remediation of the contaminants.

  13. Diverse Thinking about Diversity

    ERIC Educational Resources Information Center

    Kaplan, Sandra N.

    2013-01-01

    This article focuses on the concept of diversity in educational decision making. It is noted that the differences that distinguish the needs, interests and abilities are identified by educators. It lists misconceptions resulting from not attending to within-group diversity, and states that a "loss of self" for individual members of…

  14. Intrinsic remediation of an industrial waste impoundment

    SciTech Connect

    Swindoll, C.M.; Lee, M.D.; Wood, K.N.; Hartten, A.S.; Bishop, A.L.; Connor, J.M.

    1995-12-31

    Intrinsic remediation, also known as natural restoration, was evaluated as a potential corrective action alternative for an industrial surface impoundment previously used for the disposal of waste treatment biosolids, organic wastes, and fly ash. Organic waste constituents included chlorobenzene, aniline, xylenes, benzene, toluene, acetone, p-cresol, 2-butanone, fluorene, and ethylbenzene. The evaluation demonstrated that the impoundment contains an active microbial community including aerobic, denitrifying, sulfate-reducing, and methanogenic microbes, and that environmental conditions were favorable for their growth. Laboratory studies confirmed that these microbes could biodegrade the organic waste constituents under varying redox conditions. The sorptive properties of the residual biosolids and fly ash contribute to the immobilization of chemical constituents and may enhance biodegradation by sequestering chemicals onto surfaces where microbes grow. Based on this field and laboratory evaluation, it was concluded that intrinsic remediation offers significant environmental benefits over other corrective action alternatives that would not allow these natural restoration processes to continue in the surface impoundment.

  15. Electrochemical remediation of phenanthrene from contaminated kaolinite.

    PubMed

    Alcántara, T; Pazos, M; Cameselle, C; Sanromán, M A

    2008-04-01

    In this work a two-stage process combining soil electrokinetic remediation and liquid electrochemical oxidation for the remediation of polluted soil with organic compounds has been developed and evaluated using phenanthrene-spiked kaolinite. Application of an unenhanced electrokinetic process resulted in negligible removal of phenanthrene from the kaolinite sample. Addition of co-solvents and electrolyte to the processing fluid used in the electrode chambers enhanced phenanthrene desorption from the kaolinite matrix and favoured electro-osmotic flow. Near-complete removal of phenanthrene was achieved using Na2SO4 and ethanol in the processing fluid. Phenanthrene was transported towards the cathode chamber where it was collected. The cathodic solution containing the pollutant was treated by electrochemical oxidation; complete degradation of phenanthrene occurred after 9 h using Na2SO4 as electrolyte.

  16. Saxton soil remediation project

    SciTech Connect

    Holmes, R.D.

    1995-12-31

    The Saxton Nuclear Experimental Facility (SNEF) consists of a 23-MW(thermal) pressurized light water thermal reactor located in south central Pennsylvania. The Saxton Nuclear Experimental Corporation (SNEC), a wholly owned subsidiary of the General Public Utilities (GPU) Corporation, is the licensee for the SNEF. Maintenance and decommissioning activities at the site are conducted by GPU Nuclear, also a GPU subsidiary and operator of the Three Mile Island and Oyster Creek nuclear facilities. The remediation and radioactive waste management of contaminated soils is described.

  17. Rehabbing for remediation

    SciTech Connect

    Banton, D.; Anderson, R. )

    1994-03-01

    This article examines how rehabilitating contaminated city water wells in Moses Lake, Wash. took care of the problem for less than half the price of conventional remediation techniques. Wells located in similar hydrogeology, often found in the Western and Plains states, may benefit from this approach. Moses Lake is located on the Columbia Plateau in central Washington. The wells are between 700 and 800 ft deep, cased through 100--200 ft of alluvium, and completed open holes stretch across multiple basalt flows of the Wanapum formation of the Columbia River basalt group.

  18. Avoiding costly remediation

    SciTech Connect

    Scheels, R.H.

    1997-10-01

    Some oil and gas pipeline operations require equipment with hydraulic or oil circulation systems. These are subject to oil leaks or spills due to equipment malfunctions as well as normal operation. The potential liability and actual remediation and shutdown costs helped create the need for more environmentally friendly hydraulic fluids. Mobil has developed readily biodegradable, virtually nontoxic hydraulic fluids, Mobil EAL 224H and Mobil EAL Syndrajoc Series oils (EAL stands for Environmental Awareness Lubricants). The first is vegetable oil-based, while the others are formulated from high viscosity-index synthetic ester base stocks. Both use virtually nontoxic additive packages. These hydraulic fluids are described.

  19. Glucocorticoid-remediable aldosteronism.

    PubMed

    Halperin, Florencia; Dluhy, Robert G

    2011-06-01

    Glucocorticoid-remediable aldosteronism (GRA) is a hereditary form of primary hyperaldosteronism and the most common monogenic cause of hypertension. A chimeric gene duplication leads to ectopic aldosterone synthase activity in the cortisol-producing zona fasciculata of the adrenal cortex, under the regulation of adrenocorticotropin (ACTH). Hypertension typically develops in childhood, and may be refractory to standard therapies. Hypokalemia is uncommon in the absence of treatment with diuretics. The discovery of the genetic basis of the disorder has permitted the development of accurate diagnostic testing. Glucocorticoid suppression of ACTH is the mainstay of treatment; alternative treatments include mineralocorticoid receptor antagonists.

  20. [Vapor extraction technology in oil contaminated soil remediation].

    PubMed

    Li, Jinhui; Nie, Yongfeng; Ma, Haibin; Xia, Xin; Liang, Fuyan; Zhen, Xiaoyue

    2002-01-30

    In order to study the Vapor Extraction Technology that can be applied to China, on the basis of mechanism analysis of Vapor Extraction Technology for oil-contaminated soil, a simplified and practical contaminant removal model to simulate the soil remediation time was presented. With the typical unsaturated soils in North of China, the effects of the vapor flow rate, soil water content and quality on the remediation process were studied. The results showed that the best value of flow velocity was existed, and water content had different influence on different kinds of soil, for silty soil, the efficiency of remediation enhanced with water content increase, but there was a reverse result for clayey soil. Through one-dimension soil column experiments, the results showed that these factors had different effects on remediation time. The research using the soil column apparatus show that the predicted results were validated and the applied conditions of this model were qualified.

  1. Remediating Remediation: From Basic Writing to Writing across the Curriculum

    ERIC Educational Resources Information Center

    Faulkner, Melissa

    2013-01-01

    This article challenges faculty members and administrators to rethink current definitions of remediation. First year college students are increasingly placed into basic writing courses due to a perceived inability to use English grammar correctly, but it must be acknowledged that all students will encounter the need for remediation as they attempt…

  2. Remediation of Deep Vadose Zone Radionuclide and Metal Contamination: Status and Issues

    SciTech Connect

    Dresel, P. Evan; Truex, Michael J.; Cantrell, Keri

    2008-12-30

    This report documents the results of a PNNL literature review to report on the state of maturity of deep vadose zone remediation technologies for metal contaminants including some radionuclides. Its recommendations feed into decisionmakers need for scientific information and cost-effective in situ remediation technlogies needed under DOE's Environmental Management initiative Enhanced Remediation Methods: Scientific & Technical Basis for In Stu Treatment Systems for Metals and Radionuclides.

  3. Valuing Diversity

    PubMed Central

    Fryer, Roland G.; Loury, Glenn C.

    2014-01-01

    This paper explores the economics of diversity-enhancing policies. A model is proposed in which heterogeneous agents, distinguished by skill level and social identity, purchase productive opportunities in a competitive market. We analyze policies designed to raise the status of a disadvantaged identity group. When agent identity is contractible, efficient policy grants preferred access to slots but offers no direct assistance for acquiring skills. When identity is not contractible, efficient policy provides universal subsidies to skill development when the fraction of the disadvantaged group at the skill development margin is larger than their share at the slot assignment margin. PMID:25525280

  4. Managing soil remediation problems.

    PubMed

    Okx, J P; Hordijk, L; Stein, A

    1996-12-01

    Soil remediation has only a short history but the problem addressed is a significant one. Cost estimates for the clean-up of contaminated sites in the European Union and the United States are in the order of magnitude of 1,400 billion ECU. Such an enormous operation deserves the best management it can get. Reliable cost estimations per contaminated site are an important prerequisite. This paper addresses the problems related to site-wise estimations.When solving soil remediation problems, we have to deal with a large number of scientific disciplines. Too often solutions are presented from the viewpoint of only one discipline. In order to benefit from the combined disciplinary knowledge and experience, we think that it is necessary to describe the interrelations between these disciplines. This can be realized by developing an adequate model of the desired process which enables to consider and evaluate the essential factors as interdependent components of the total system.The resulting model provides a binding paradigm to the contributing disciplines which will result in improved efficiency and effectivity of the decision and the cost estimation process. In the near future, we will release the "Biosparging and Bioventing Expert Support System", an expert support system for problem owners, consultants and authorities dealing with the design and operation of a biosparging and/or a bioventing system.

  5. Soil Remediation Test

    SciTech Connect

    Manlapig, D. M.; Williamsws

    2002-04-01

    Soils contaminated with petroleum by-products can now be effectively remediated using a variety of technologies. Among these are in-situ bioremediation, land farming, and landfill/replacing of soil. The range of efficiencies and cost effectiveness of these technologies has been well documented. Exsorbet Plus is showing promise as an in-situ bioremediation agent. It is made of naturally grown Spaghnum Peat Moss which has been activated for encapsulation and blended with nitrogen-rich fertilizer. In its initial field test in Caracas, Venezuela, it was able to remediate crude oil-contaminated soil in 90 days at less than half of the cost of competing technologies. Waste Solutions, Corp and the US Department of Energy signed a Cooperative Research and Development Agreement to test Exsorbet Plus at the Rocky Mountain Oilfield Testing Center near Casper, Wyoming. As part of the test, soil contaminated with crude oil was treated with Exsorbet Plus to aid the in-situ bioremediation process. Quantitative total petroleum hydrocarbon (TPH) measurements were acquired comparing the performance of Exsorbet Plus with an adjacent plot undergoing unaided in-situ bioremediation.

  6. Home Assessment and Remediation.

    PubMed

    Barnes, Charles S; Horner, W Elliott; Kennedy, Kevin; Grimes, Carl; Miller, J David

    2016-01-01

    Awareness of the relationship of fungi to asthma in indoor air is very old and well documented. There is substantial evidence that mold and dampness exacerbate asthma in sensitized individuals. Many governmental and nongovernmental organizations around the world have issued guidelines to the effect that the elimination of moisture intrusion and the removal of moldy items from living space can improve respiratory health. The process of home assessment for moisture and mold presence is discussed along with factors that can be used to guide fungal exposure reduction efforts. An approach to the assessment process itself is outlined, and common causes of moisture and mold damage are described. Points that should be included in a report resulting from a home assessment and rudimentary elements of report interpretation are discussed. Emphasis is that interpretation of sampling for moisture and fungal presence should be provided by the person performing the assessment. We conclude that multifaceted remediation contributes to fungal allergen avoidance. The use of an indoor environmental professional to generate evaluation reports and remediation activities can be a valuable contribution to an overall allergen avoidance strategy.

  7. Partnership to Enhance Diversity in Marine Geosciences: Holocene Climate and Anthorpogenic Changes from Long Island Sound, NY

    NASA Astrophysics Data System (ADS)

    McHugh, C. M.; Cormier, M.; Marchese, P.; Zheng, Y.; Kohfeld, K.

    2006-12-01

    This NSF-funded program developed an oceanographic field experience coupled to a strong curriculum and one-on-one mentoring of individual research projects, as a means to increase diversity in the geosciences. The working hypothesis is that New York City students will be attracted to geosciences through an integrated field and research experience that familiarizes them with their environment. As part of this program, multidisciplinary investigations of Long Island Sound were conducted from the R/V Hugh Sharp, part of the University-National Oceanographic Laboratory System (UNOLS) fleet, for one-week during June 2006. Nine students from underrepresented groups in the geosciences (native Americans, Hispanics, and African- Americans) and five investigators from various institutions specializing in marine geophysics, geology, geochemistry, biology, and physical oceanography participate in this project. The expedition introduced the students to a variety of oceanographic techniques, including multibeam bathymetric mapping, high-resolution subbottom profiling, side scan sonar, sediment, water, and biological sampling, and current profiling. The collected dataset is now analyzed by the students to extract the late Quaternary history of Long Island Sound and to assess the impact of anthropogenic activities in the sediments, waters, and ecosystems. 85 % of the student participants have declared either a geoscience and/or environmental science major with concentrations in biology and geosciences. Recruiting for the program relied on partnerships with: 1) Alliance for Minority Participation (AMP) Program of the City University of New York (CUNY). A program supported by the National Science Foundation and in which Queens College (QC) and CUNY participate; 2) the Search for Education, Elevation, and Knowledge Program (SEEK) in place at Queens College. A program designed to provide educational opportunities for academically motivated students who need substantial financial

  8. Diverse role of fast growing rhizobia in growth promotion and enhancement of psoralen content in Psoralea corylifolia L

    PubMed Central

    Prabha, Chandra; Maheshwari, D. K.; Bajpai, Vivek K.

    2013-01-01

    Background: Psoralea corylifolia (Bakuchi), a weed, which possesses a highly potent and medicinally important compound psoralen. P. corylifolia has been widely exploited since ages for its biological potential. Materials and Methods: Fifteen root nodulating bacteria as pure culture collection (PCC) were isolated from P. corylifolia in India. Further, these strains were evaluated for their effect on the psoralen content in P. corylifolia. High performance liquid chromatography (HPLC) method was used for the estimation of psoralen in P. corylifolia seed extracts. The effectiveness of these rhizobial strains was assessed on the basis of screening of various plant growth promoting attributes. Results: The 16S ribosomal RNA sequencing analysis revealed the identity of two most effective rhizobial isolates PCC2 and PCC7 as Rhizobium leguminosarum and Sinorhizobium meliloti, respectively. The R. leguminosarum PCC2 (JN546144) and Ensifer meliloti PCC7 (JN546145) strains showed solubilization of insoluble inorganic phosphate, secreted indole acetic acid (IAA), produced siderophore, showed ACC deaminase activity, and were positive for nodulation and nitrogen fixing genes. Seeds of P. corylifolia were bacterized with combination of R. leguminosarum PCC2 and Ensifer meliloti PCC7 along with their individual application that resulted in enhancement of various early vegetative and late reproduction parameters of plants in two consecutive field trials in the year 2009 and 2010. The psoralen content in the seeds of P. corylifolia was observed to be increased in the field trials where the combination of rhizobial strains PCC2 and PCC7 was used (2.79%) compared to control (1.91%). Conclusion: These findings indicate that rhizobial strains PCC2 and PCC7 showing good plant growth promoting attributes can be effective for increasing the psoralen content in the seeds of P. corylifolia to a certain level. PMID:24143046

  9. Interpersonal Needs of Remedial Readers.

    ERIC Educational Resources Information Center

    Cochran, Judith

    A study sought to determine the effects of reading deficiency on the interpersonal relationship needs of regular and remedial readers as composite groups and on elementary and secondary school remedial and regular readers as age groups. Elementary and secondary school students were randomly selected and tested on the Gates-MacGinitie Reading Tests…

  10. Innovative Technologies for Chlorinated Solvent Remediation

    NASA Astrophysics Data System (ADS)

    Pennell, Kurt D.; Cápiro, Natalie L.

    2014-07-01

    The following sections are included: * INTRODUCTION * TRADITIONAL REMEDIATION TECHNOLOGIES (1980s) * RESEARCH AND DEVELOPMENT OF INNOVATIVE REMEDIATION TECHNOLOGIES (1990s-2000s) * CURRENT TRENDS IN CHLORINATED SOLVENT REMEDIATION (2010s) * CLOSING THOUGHTS * REFERENCES

  11. Remediation using nested, horizontal wells

    SciTech Connect

    Desantis, P.J.; Andrilenas, J.S.; Cheng, S.; Esler, C.; Miller, R.S.; Lew, K.V.

    1995-11-01

    A pair of nested, horizontal wells (one for vapor extraction, one for groundwater extraction) were utilized to remediate a mixed aromatic volatile organic compound (AVOC) and halogenated volatile organic compound (HVOC) soil and groundwater plume. The project site is an operating gasoline service station located in Portland, Oregon. The site has low permeability soils, a thin unconfined aquifer, with a relatively steep groundwater gradient. Each of the nested horizontal wells was drilled using the continuous borehole directional drilling method. The wells are each 110 meters long employing 73 meters of pre-packed well screen. The groundwater extraction well was pumped via vacuum-enhanced methods utilizing a two-pump configuration to eliminate the need for installation of a pump within the horizontal well and to increase both flow and radius of influence in fine-grained soils. Two groundwater models, a 2D analytical model and a finite element model, were utilized to analyze the potential and actual performance of the well. Of the two models used, the finite element model has produced results closely matching the actual performance of the well. After one year of operation, both AVOCs and HVOCs concentrations have been reduced by between 70 to 100%. All but two downgradient site wells have met cleanup standards for AVOCs; all have met substantial compliance for HVOCs.

  12. Computer-Assisted Remedial Reading Intervention for School Beginners at Risk for Reading Disability

    ERIC Educational Resources Information Center

    Saine, Nina L.; Lerkkanen, Marja-Kristiina; Ahonen, Timo; Tolvanen, Asko; Lyytinen, Heikki

    2011-01-01

    The aim of the longitudinal study was to investigate whether a computer application designed for remedial reading training can enhance letter knowledge, reading accuracy, fluency, and spelling of at-risk children. The participants, 7-year-old Finnish school beginners (N = 166), were assigned to 1 of 3 groups: (a) regular remedial reading…

  13. Electrokinetic remediation of fluorine-contaminated soil: conditioning of anolyte.

    PubMed

    Kim, Do-Hyung; Jeon, Chil-Sung; Baek, Kitae; Ko, Sung-Hwan; Yang, Jung-Seok

    2009-01-15

    The feasibility of anolyte conditioning on electrokinetic remediation of fluorine-contaminated soil was investigated with a field soil. The initial concentration of fluorine, pH and water content in the soil were 414mg/kg, 8.91 and 15%, respectively. Because the extraction of fluorine generally increased with the soil pH, the pH of the anode compartment was controlled by circulating strong alkaline solution to enhance the extraction of fluorine during electrokinetic remediation. The removal of fluorine increased with the concentration of the alkaline solution and applied current density and fluorine removed up to 75.6% within 14 days. Additionally, anolyte conditioning sharply increased the electro-osmotic flow, which enhanced the removal of fluorine in this study. In many respects, anolyte conditioning in electrokinetic remediation of fluorine-contaminated soil will be a promising technology.

  14. Monitoring engineered remediation with borehole radar

    USGS Publications Warehouse

    Lane, J.W.; Day-Lewis, F. D.; Joesten, P.K.

    2007-01-01

    The success of engineered remediation is predicated on correct emplacement of either amendments (e.g., vegetable-oil emulsion, lactate, molasses, etc.) or permeable reactive barriers (e.g., vegetable oil, zero-valent iron, etc.) to enhance microbial or geochemical breakdown of contaminants and treat contaminants. Currently, site managers have limited tools to provide information about the distribution of injected materials; the existence of gaps or holes in barriers; and breakdown or transformation of injected materials over time. ?? 2007 Society of Exploration Geophysicists.

  15. Applications of microwave radiation environmental remediation technologies

    SciTech Connect

    Krause, T.R.; Helt, J.E.

    1993-05-01

    A growing number of environmental remediation technologies (e.g., drying, melting, or sintering) utilize microwave radiation as an integral part of the process. An increasing number of novel applications, such as sustaining low-temperature plasmas or enhancing chemical reactivity, are also being developed. An overview of such technologies being developed by the Department of Energy is presented. A specific example being developed at Argonne National Laboratory, microwave-induced plasma reactors for the destruction of volatile organic compounds, is discussed in more detail.

  16. Applications of microwave radiation environmental remediation technologies

    SciTech Connect

    Krause, T.R.; Helt, J.E.

    1993-01-01

    A growing number of environmental remediation technologies (e.g., drying, melting, or sintering) utilize microwave radiation as an integral part of the process. An increasing number of novel applications, such as sustaining low-temperature plasmas or enhancing chemical reactivity, are also being developed. An overview of such technologies being developed by the Department of Energy is presented. A specific example being developed at Argonne National Laboratory, microwave-induced plasma reactors for the destruction of volatile organic compounds, is discussed in more detail.

  17. Simultaneous Presence of Insertion Sequence Excision Enhancer and Insertion Sequence IS629 Correlates with Increased Diversity and Virulence in Shiga Toxin-Producing Escherichia coli

    PubMed Central

    Toro, M.; Rump, L. V.; Cao, G.; Meng, J.; Brown, E. W.

    2015-01-01

    Although new serotypes of enterohemorrhagic Escherichia coli (EHEC) emerge constantly, the mechanisms by which these new pathogens arise and the reasons emerging serotypes tend to carry more virulence genes than other E. coli are not understood. An insertion sequence (IS) excision enhancer (IEE) was discovered in EHEC O157:H7 that promoted the excision of IS3 family members and generating various genomic deletions. One IS3 family member, IS629, actively transposes and proliferates in EHEC O157:H7 and enterotoxigenic E. coli (ETEC) O139 and O149. The simultaneous presence of the IEE and IS629 (and other IS3 family members) may be part of a system promoting not only adaptation and genome diversification in E. coli O157:H7 but also contributing to the development of pathogenicity among predominant serotypes. Prevalence comparisons of these elements in 461 strains, representing 72 different serotypes and 5 preassigned seropathotypes (SPT) A to E, showed that the presence of these two elements simultaneously was serotype specific and associated with highly pathogenic serotypes (O157 and top non-O157 Shiga toxin-producing Escherichia coli [STEC]) implicated in outbreaks and sporadic cases of human illness (SPT A and B). Serotypes lacking one or both elements were less likely to have been isolated from clinical cases. Our comparisons of IEE sequences showed sequence variations that could be divided into at least three clusters. Interestingly, the IEE sequences from O157 and the top 10 non-O157 STEC serotypes fell into clusters I and II, while less commonly isolated serotypes O5 and O174 fell into cluster III. These results suggest that IS629 and IEE elements may be acting synergistically to promote genome plasticity and genetic diversity among STEC strains, enhancing their abilities to adapt to hostile environments and rapidly take up virulence factors. PMID:26292302

  18. Agar agar-stabilized milled zerovalent iron particles for in situ groundwater remediation.

    PubMed

    Velimirovic, Milica; Schmid, Doris; Wagner, Stephan; Micić, Vesna; von der Kammer, Frank; Hofmann, Thilo

    2016-09-01

    Submicron-scale milled zerovalent iron (milled ZVI) particles produced by grinding macroscopic raw materials could provide a cost-effective alternative to nanoscale zerovalent iron (nZVI) particles for in situ degradation of chlorinated aliphatic hydrocarbons in groundwater. However, the aggregation and settling of bare milled ZVI particles from suspension presents a significant obstacle to their in situ application for groundwater remediation. In our investigations we reduced the rapid aggregation and settling rate of bare milled ZVI particles from suspension by stabilization with a "green" agar agar polymer. The transport potential of stabilized milled ZVI particle suspensions in a diverse array of natural heterogeneous porous media was evaluated in a series of well-controlled laboratory column experiments. The impact of agar agar on trichloroethene (TCE) removal by milled ZVI particles was assessed in laboratory-scale batch reactors. The use of agar agar significantly enhanced the transport of milled ZVI particles in all of the investigated porous media. Reactivity tests showed that the agar agar-stabilized milled ZVI particles were reactive towards TCE, but that their reactivity was an order of magnitude less than that of bare, non-stabilized milled ZVI particles. Our results suggest that milled ZVI particles could be used as an alternative to nZVI particles as their potential for emplacement into contaminated zone, their reactivity, and expected longevity are beneficial for in situ groundwater remediation.

  19. Identification of functionally relevant populations in enhanced biological phosphorus removal processes based on intracellular polymers profiles and insights into the metabolic diversity and heterogeneity.

    PubMed

    Majed, Nehreen; Chernenko, Tatyana; Diem, Max; Gu, April Z

    2012-05-01

    This study proposed and demonstrated the application of a new Raman microscopy-based method for metabolic state-based identification and quantification of functionally relevant populations, namely polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), in enhanced biological phosphorus removal (EBPR) system via simultaneous detection of multiple intracellular polymers including polyphosphate (polyP), glycogen, and polyhydroxybutyrate (PHB). The unique Raman spectrum of different combinations of intracellular polymers within a cell at a given stage of the EBPR cycle allowed for its identification as PAO, GAO, or neither. The abundance of total PAOs and GAOs determined by Raman method were consistent with those obtained with polyP staining and fluorescence in situ hybridization (FISH). Different combinations and quantities of intracellular polymer inclusions observed in single cells revealed the distribution of different sub-PAOs groups among the total PAO populations, which exhibit phenotypic and metabolic heterogeneity and diversity. These results also provided evidence for the hypothesis that different PAOs may employ different extents of combination of glycolysis and TCA cycle pathways for anaerobic reducing power and energy generation and it is possible that some PAOs may rely on TCA cycle solely without glycolysis. Sum of cellular level quantification of the internal polymers associated with different population groups showed differentiated and distributed trends of glycogen and PHB level between PAOs and GAOs, which could not be elucidated before with conventional bulk measurements of EBPR mixed cultures.

  20. Identification of functionally relevant populations in enhanced biological phosphorus removal processes based on intracellular polymers profiles and insights into the metabolic diversity and heterogeneity.

    PubMed

    Majed, Nehreen; Chernenko, Tatyana; Diem, Max; Gu, April Z

    2012-05-01

    This study proposed and demonstrated the application of a new Raman microscopy-based method for metabolic state-based identification and quantification of functionally relevant populations, namely polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), in enhanced biological phosphorus removal (EBPR) system via simultaneous detection of multiple intracellular polymers including polyphosphate (polyP), glycogen, and polyhydroxybutyrate (PHB). The unique Raman spectrum of different combinations of intracellular polymers within a cell at a given stage of the EBPR cycle allowed for its identification as PAO, GAO, or neither. The abundance of total PAOs and GAOs determined by Raman method were consistent with those obtained with polyP staining and fluorescence in situ hybridization (FISH). Different combinations and quantities of intracellular polymer inclusions observed in single cells revealed the distribution of different sub-PAOs groups among the total PAO populations, which exhibit phenotypic and metabolic heterogeneity and diversity. These results also provided evidence for the hypothesis that different PAOs may employ different extents of combination of glycolysis and TCA cycle pathways for anaerobic reducing power and energy generation and it is possible that some PAOs may rely on TCA cycle solely without glycolysis. Sum of cellular level quantification of the internal polymers associated with different population groups showed differentiated and distributed trends of glycogen and PHB level between PAOs and GAOs, which could not be elucidated before with conventional bulk measurements of EBPR mixed cultures. PMID:22471394

  1. Covert Operant Reinforcement of Remedial Reading Learning Tasks.

    ERIC Educational Resources Information Center

    Schmickley, Verne G.

    The effects of covert operant reinforcement upon remedial reading learning tasks were investigated. Forty junior high school students were taught to imagine either neutral scenes (control) or positive scenes (treatment) upon cue while reading. It was hypothesized that positive covert reinforcement would enhance performance on several measures of…

  2. FOAM: NOVEL DELIVERY TECHNOLOGY FOR REMEDIATION OF VADOSE ZONE ENVIRONMENTS

    SciTech Connect

    Jansik, Danielle P.; Wellman, Dawn M.; Mattigod, Shas V.; Zhong, Lirong; Wu, Yuxin; Foote, Martin; Zhang, Z. F.; Hubbard, Susan

    2011-07-05

    Deep vadose zone environments can be a primary source and pathway for contaminant migration to groundwater. These environments present unique characterization and remediation challenges that necessitate scrutiny and research. The thickness, depth, and intricacies of the deep vadose zone, combined with a lack of understanding of the key subsurface processes (e.g., biogeochemical and hydrologic) affecting contaminant migration, make it difficult to create validated conceptual and predictive models of subsurface flow dynamics and contaminant behavior across multiple scales. These factors also make it difficult to design and deploy sustainable remedial approaches and monitor long-term contaminant behavior after remedial actions. Functionally, the methods for addressing contamination must remove and/or reduce transport of contaminants. This problem is particularly challenging in the arid western United States where the vadose zone is hundreds of feet thick, rendering transitional excavation methods exceedingly costly and ineffective. Delivery of remedial amendments is one of the most challenging and critical aspects for all remedy-based approaches. The conventional approach for delivery is through injection of aqueous remedial solutions. However, heterogeneous deep vadose zone environments present hydrologic and geochemical challenges which limit the effectiveness. Because the flow of solution infiltration is dominantly controlled by gravity and suction, injected liquid preferentially percolates through highly permeable pathways, by-passing low-permeability zones which frequently contain the majority of contamination. Moreover, the wetting front can readily mobilize and enhance contaminant transport to the underlying aquifer prior to stabilization. Development of innovative, in-situ technologies may be the only way to meet remedial action objectives and long-term stewardship goals. Surfactants can be used to lower the liquid surface tension and create stabile foams

  3. Enhancing Diversity in the Geosciences

    ERIC Educational Resources Information Center

    Wechsler, Suzanne P.; Whitney, David J.; Ambos, Elizabeth L.; Rodrigue, Christine M.; Lee, Christopher T.; Behl, Richard J.; Larson, Daniel O.; Francis, Robert D.; Hold, Gregory

    2005-01-01

    An innovative interdisciplinary project at California State University, Long Beach, was designed to increase the attractiveness of the geosciences (physical geography, geology, and archaeology) to underrepresented groups. The goal was to raise awareness of the geosciences by providing summer research opportunities for underrepresented high school…

  4. Remediation of contaminated soils

    SciTech Connect

    Radhakrishnan, R.; Ariza, C.H.

    1997-07-01

    At least three types of zones of contamination exist whenever there is a chemical release. The impact of Non-Aqueous-Phase Liquids (NAPL) on soils and groundwater, together with the ultimate transport and migration of constituent chemicals in their dissolved or sorbed states, had led environmentalists to develop several techniques for cleaning a contaminated soil. Zone 1 represents the unsaturated zone which could be contaminated to retention capacity by both Dense Non-Aqueous-Phase Liquids (DNAPL) and Light Non-Aqueous-Phase Liquids (LNAPL). Zone 2 represents residual DNAPL or LNAPL contamination found below the groundwater table in the saturated zone. Zone 3 is represented by either the presence of NAPL dissolved in the aqueous phase, volatilized in the unsaturated zone or sorbed to either saturated or unsaturated soils. Cleanup of petroleum contaminated soils is presented in this paper. Among several techniques developed for this purpose, in-situ biological remediation is discussed in detail as a technique that does not involve excavation, thus, the costs and disruption of excavating soil are eliminated.

  5. ICDF Complex Remedial Action Report

    SciTech Connect

    W. M. Heileson

    2007-09-26

    This Idaho CERCLA Disposal Facility (ICDF) Remedial Action Report has been prepared in accordance with the requirements of Section 6.2 of the INEEL CERCLA Disposal Facility Remedial Action Work Plan. The agency prefinal inspection of the ICDF Staging, Storage, Sizing, and Treatment Facility (SSSTF) was completed in June of 2005. Accordingly, this report has been developed to describe the construction activities completed at the ICDF along with a description of any modifications to the design originally approved for the facility. In addition, this report provides a summary of the major documents prepared for the design and construction of the ICDF, a discussion of relevant requirements and remedial action objectives, the total costs associated with the development and operation of the facility to date, and identification of necessary changes to the Agency-approved INEEL CERCLA Disposal Facility Remedial Action Work Plan and the ICDF Complex Operations and Maintenance Plan.

  6. A Framework for Remediating Number Combination Deficits

    ERIC Educational Resources Information Center

    Fuchs, Lynn S.; Powell, Sarah R.; Seethaler, Pamela M.; Fuchs, Douglas; Hamlett, Carol L.; Cirino, Paul T.; Fletcher, Jack M.

    2010-01-01

    This article introduces a framework for the remediation of number combination (NC) deficits. Research on the remediation of NC deficits is summarized, and research program studies are used to illustrate the 3 approaches to remediation. The Framework comprises a 2-stage system of remediation. The less intensive stage implementing 1 of 3…

  7. LEAKING UNDERGROUND STORAGE TANKS: REMEDIATION WITH EMPHASIS ON IN SITU BIORESTORATION

    EPA Science Inventory

    The current literature indicates that in situ biorestoration has great potential for remediation of aquifers contaminated by leaking underground storage tanks. In situ aquifer restoration involves the enhancement of the indigenous microflora to degrade subsurface pollutants. The ...

  8. WATER AS A REAGENT FOR SOIL REMEDIATION

    SciTech Connect

    Indira S. Jayaweera; Jordi Diaz-Ferraro

    2000-02-28

    SRI International is conducting experiments to develop and evaluate hydrothermal extraction technology for remediating petroleum-contaminated soils. Most current remediation practices generally fail (or are cost prohibitive) to remove the polycyclic aromatic hydrocarbons (PAHs) found in petroleum-contaminated sites or they require the use of organic solvents to achieve removal, at the expense of additional contamination and with the added cost of recycling solvents. Hydrothermal extraction offers the promise of efficiently extracting PAHs and other kinds of organics from contaminated soils at moderate temperatures and pressures, using only water and inorganic salts such as carbonate. Initial work is being conducted at SRI to measure the solubility and rate of solubilization of selected PAHs (anthracene, fluoranthene, pyrene, and chrysene) in water, using SRI's hydrothermal optical cell with the addition of varying amounts of sodium carbonate to evaluate the efficiency of the technology for removing PAHs from the soil. Preliminary results with pyrene and fluoranthene in water clearly indicate a significant enhancement of solubility with increase in temperature. During this quarter, we conducted experiments with pyrene in the temperature range 200 to 300 C and observed a great enhancement in solubility with an increase in temperature. We also started experiments with real-world soil samples purchased from the subcontractor.

  9. Building Successful Programs to Increase Diversity in the Geosciences Through HBCU/Research Center Collaborations: Lessons to Enhance Rates of Participation Nationally

    NASA Astrophysics Data System (ADS)

    Gilligan, M. R.; Frischer, M. E.; Verity, P. G.

    2004-12-01

    In view of changing demography of the U.S. and the world, it is important that all groups be involved in sustaining and enhancing the vitality and importance of the geosciences. Though Historically Black Colleges and Universities (HBCUs) enroll only 13% of the African Americans who are in college, they award 40% of the science degrees earned by African Americans in the U.S. However, relatively few HBCUs have geoscience programs and faculty who provide exposure, curricula or research opportunities for students to explore options in earth, atmospheric or ocean sciences on their campuses. There is not enough exposure to geosciences at HBCUs. Non-degree granting research institutes and centers have as their primary mission research and compete successfully with research universities for federal and state research funding. However, these institutions lack experience, expertise, and access/visibility to African American students. There are not enough programs at research centers to attract African Americans. Through collaboration with research institutions, Savannah State University (SSU), an HBCU founded in 1890 in Savannah, Georgia, has built successful marine science undergraduate and graduate programs. Since 1999, SSU and the Skidaway Institute of Oceanography (SkIO, a research center founded in 1968) have formally collaborated to join their respective strengths with the goal of providing SSU students expanded undergraduate and graduate curricular offerings and unique research opportunities. The objective is to enhance student motivation and skills to compete successfully for graduate school admission and jobs in the geosciences. At the core is hands-on experiential learning and improved access to leaders in the field. Students report that the opportunity to conduct research, to meet eminent scientists, and to attend national and international scientific conferences provides them with the training, opportunity, motivation, and confidence to pursue advanced degrees

  10. Early Entry for Youth into the Ocean Science Pipeline Through Ocean Science School Camp and Summer Camp Programs: A Key Strategy for Enhancing Diversity in the Ocean Sciences

    NASA Astrophysics Data System (ADS)

    Crane, N. L.; Wasser, A.; Weiss, T.; Sullivan, M.; Jones, A.

    2004-12-01

    Educators, policymakers, employers and other stakeholders in ocean and other geo-science fields face the continuing challenge of a lack of diversity in these fields. A particular challenge for educators and geo-science professionals promoting ocean sciences is to create programs that have broad access, including access for underrepresented youth. Experiential learning in environments such as intensive multi-day science and summer camps can be a critical captivator and motivator for young people. Our data suggest that youth, especially underrepresented youth, may benefit from exposure to the oceans and ocean science through intensive, sustained (eg more than just an afternoon), hands-on, science-based experiences. Data from the more than 570 youth who have participated in Camp SEA Lab's academically based experiential ocean science camp and summer programs provide compelling evidence for the importance of such programs in motivating young people. We have paid special attention to factors that might play a role in recruiting and retaining these young people in ocean science fields. Over 50% of program attendees were underrepresented youth and on scholarship, which gives us a closer look at the impact of such programs on youth who would otherwise not have the opportunity to participate. Both cognitive (knowledge) and affective (personal growth and motivation) indicators were assessed through surveys and questionnaires. Major themes drawn from the data for knowledge growth and personal growth in Camp SEA Lab youth attendees will be presented. These will be placed into the larger context of critical factors that enhance recruitment and retention in the geo-science pipeline. Successful strategies and challenges for involving families and broadening access to specialized programs such as Camp SEA Lab will also be discussed.

  11. Current Status and Future Trends of Diversity Initiatives in the Workplace: Diversity Experts' Perspective.

    ERIC Educational Resources Information Center

    Wentling, Rose Mary; Palma-Rivas, Nilda

    1998-01-01

    In-depth interviews with 12 diversity experts identified organizational and individual barriers inhibiting development of a diverse workforce. Primary reasons for diversity initiatives included improving productivity, enhancing social responsibility, and addressing legal concerns. (SK)

  12. Remediation of contaminated soils and sediments using Daramend bioremediation

    SciTech Connect

    Burwell, S.W.; Bucens, P.G.; Seech, A.G.

    1996-05-01

    Soils and sediments containing polyaromatic hydrocarbons (PAH), petroleum hydrocarbons, heavy oils, chlorinated phenols, pesticides, herbicides and phthalates, either individually or in combination, have been difficult to remediate in the past. Not only the species of contaminant, but contaminant concentrations were roadblocks to successful use of bioremediation. Daramend{sup Tm} remediation has removed many of these obstacles through extensive research. Bench-scale, pilot-scale and full-scale demonstrations have been conducted at a variety of industrial sites. At a manufactured gas site, 295 days of Daramend remediation reduced concentrations of chrysene and fluoranthene from 38.9 mg/kg to 5.9 mg/kg and 84.6 mg/kg to 7.8 mg/kg respectively. Elsewhere, the total PAH concentration in a silty soil was reduced from 1,442 mg/kg to 36 mg/kg. Concentrations of even the most refractory PAHs (e.g. pyrene, benzo(a)pyrene) were reduced to below the established clean-up guidelines. Total petroleum hydrocarbons (diesel fuel) have also been reduced from 8,700 mg/kg to 34 mg/kg after 182 days of treatment. Similarly, in a clay soil contaminated by crude oil processing, the concentrations of high molecular weight aliphatic hydrocarbons were rapidly reduced (138 days) to below the remediation criteria. Demonstrations with wood treatment site soils have proven Daramend remediation effective in enhancing the target compound degradation rates. Soils containing 2170 mg PCP/kg were shown to contain only 11 mg PCP/kg after 280 days of Darmend remediation. The issue of toxicity of soil containing increased amounts of pentachlorophenols was solved. Performance data collected during these projects indicate that Daramend remediation provides a cost effective method for clean-up of soils and sediments containing a variety of organic compounds.

  13. Spectral induced polarization for monitoring electrokinetic remediation processes

    NASA Astrophysics Data System (ADS)

    Masi, Matteo; Losito, Gabriella

    2015-12-01

    Electrokinetic remediation is an emerging technology for extracting heavy metals from contaminated soils and sediments. This method uses a direct or alternating electric field to induce the transport of contaminants toward the electrodes. The electric field also produces pH variations, sorption/desorption and precipitation/dissolution of species in the porous medium during remediation. Since heavy metal mobility is pH-dependent, the accurate control of pH inside the material is required in order to enhance the removal efficiency. The common approach for monitoring the remediation process both in laboratory and in the field is the chemical analysis of samples collected from discrete locations. The purpose of this study is the evaluation of Spectral Induced Polarization as an alternative method for monitoring geochemical changes in the contaminated mass during remediation. The advantage of this technique applied to field-scale is to offer higher resolution mapping of the remediation site and lower cost compared to the conventional sampling procedure. We carried out laboratory-scale electrokinetic remediation experiments on fine-grained marine sediments contaminated by heavy metal and we made Spectral Induced Polarization measurements before and after each treatment. Measurements were done in the frequency range 10- 3-103 Hz. By the deconvolution of the spectra using the Debye Decomposition method we obtained the mean relaxation time and total chargeability. The main finding of this work is that a linear relationship exists between the local total chargeability and pH, with good agreement. The observed behaviour of chargeability is interpreted as a direct consequence of the alteration of the zeta potential of the sediment particles due to pH changes. Such relationship has a significant value for the interpretation of induced polarization data, allowing the use of this technique for monitoring electrokinetic remediation at field-scale.

  14. Mathematical Modelling of Bacterial Populations in Bio-remediation Processes

    NASA Astrophysics Data System (ADS)

    Vasiliadou, Ioanna A.; Vayenas, Dimitris V.; Chrysikopoulos, Constantinos V.

    2011-09-01

    An understanding of bacterial behaviour concerns many field applications, such as the enhancement of water, wastewater and subsurface bio-remediation, the prevention of environmental pollution and the protection of human health. Numerous microorganisms have been identified to be able to degrade chemical pollutants, thus, a variety of bacteria are known that can be used in bio-remediation processes. In this study the development of mathematical models capable of describing bacterial behaviour considered in bio-augmentation plans, such as bacterial growth, consumption of nutrients, removal of pollutants, bacterial transport and attachment in porous media, is presented. The mathematical models may be used as a guide in designing and assessing the conditions under which areas contaminated with pollutants can be better remediated.

  15. Can Stress Enhance Phytoremediation of Polychlorinated Biphenyls?

    PubMed Central

    Kalinowski, Tomasz; Halden, Rolf U.

    2012-01-01

    Abstract Phytoremediation—plant-facilitated remediation of polluted soil and groundwater—is a potentially effective treatment technology for the remediation of heavy metals and certain organic compounds. However, contaminant attenuation rates are often not rapid enough to make phytoremediation a viable option when compared with alternative treatment approaches. Different strategies are being employed to enhance the efficacy of phytoremediation, including modification to the plant genome, inoculation of the rhizosphere with specialized and/or engineered bacteria, and treatment of the soil with supplementary chemicals, such as surfactants, chelators, or fertilizers. Despite these efforts, greater breakthroughs are necessary to make phytoremediation a viable technology. Here, we introduce and discuss the concept of integrating controlled environmental stresses as a strategy for enhancing phytoremediation. Plants have a diverse suite of defense mechanisms that are only induced in response to stress. Here, we examine some stress-response mechanisms in plants, focusing on defenses involving physiological changes that alter the soil microenvironment (rhizosphere), and outline how these defense mechanisms can be co-opted to enhance the effectiveness of phytoremediation of polychlorinated biphenyls and other contaminants. PMID:23236249

  16. Can Stress Enhance Phytoremediation of Polychlorinated Biphenyls?

    PubMed

    Kalinowski, Tomasz; Halden, Rolf U

    2012-12-01

    Phytoremediation-plant-facilitated remediation of polluted soil and groundwater-is a potentially effective treatment technology for the remediation of heavy metals and certain organic compounds. However, contaminant attenuation rates are often not rapid enough to make phytoremediation a viable option when compared with alternative treatment approaches. Different strategies are being employed to enhance the efficacy of phytoremediation, including modification to the plant genome, inoculation of the rhizosphere with specialized and/or engineered bacteria, and treatment of the soil with supplementary chemicals, such as surfactants, chelators, or fertilizers. Despite these efforts, greater breakthroughs are necessary to make phytoremediation a viable technology. Here, we introduce and discuss the concept of integrating controlled environmental stresses as a strategy for enhancing phytoremediation. Plants have a diverse suite of defense mechanisms that are only induced in response to stress. Here, we examine some stress-response mechanisms in plants, focusing on defenses involving physiological changes that alter the soil microenvironment (rhizosphere), and outline how these defense mechanisms can be co-opted to enhance the effectiveness of phytoremediation of polychlorinated biphenyls and other contaminants.

  17. SURFACTANTS AND SUBSURFACE REMEDIATION

    EPA Science Inventory

    Because of the limitations of pump-and-trat technology, attention is now focused on the feasibility of surfactant use to increase its efficiency. Surfactants have been studied for use in soil washing and enhanced oil recovery. Although similarities exist between the application...

  18. The norms, rules and motivational values driving sustainable remediation of contaminated environments: A study of implementation.

    PubMed

    Prior, Jason

    2016-02-15

    Efforts to achieve sustainability are transforming the norms, rules and values that affect the remediation of contaminated environments. This is altering the ways in which remediation impacts on the total environment. Despite this transformation, few studies have provided systematic insights into the diverse norms and rules that drive the implementation of sustainable remediation at contaminated sites, and no studies have investigated how values motivate compliance with these norms and rules. This study is a systematic analysis of the rules, norms and motivational values embedded in sustainable remediation processes at three sites across Australia, using in-depth interviews conducted with 18 participants between 2011 and 2014, through the application of Crawford and Ostrom's Institutional Grammar and Schwartz's value framework. These approaches offered methods for identifying the rules, norms, and motivational values that guided participants' actions within remediation processes at these sites. The findings identify a core set of 16 norms and 18 rules (sanctions) used by participants to implement sustainable remediation at the sites. These norms and rules: define the position of participants within the process, provide means for incorporating sustainability into established remediation practices, and define the scope of outcomes that constitute sustainable remediation. The findings revealed that motivational values focused on public interest and self-interest influenced participants' compliance with norms and rules. The findings also found strong interdependence between the norms and rules (sanctions) within the remediation processes and the normative principles operating within the broader domain of environmental management and planning. The paper concludes with a discussion of: the system of norms operating within sustainable remediation (which far exceed those associated with ESD); their link, through rules (sanctions) to contemporary styles of regulatory

  19. Report From the Working Group Conference on Multisite Trial Design for Cognitive Remediation in Schizophrenia

    PubMed Central

    Keefe, Richard S. E.; Vinogradov, Sophia; Medalia, Alice; Silverstein, Steven M.; Bell, Morris D.; Dickinson, Dwight; Ventura, Joseph; Marder, Stephen R.; Stroup, T. Scott

    2011-01-01

    The National Institute of Mental Health (NIMH)-Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Project and related efforts have stimulated the initiation of several studies of pharmacologic treatments for cognitive impairment in schizophrenia. Cognitive remediation may provide an excellent platform for the provision of new learning opportunities and the acquisition of new skills for patients who are engaged in pharmacologic trials to improve cognition. However, it is not clear how a cognitive remediation intervention would be employed in multisite clinical trials. A meeting of experts on cognitive remediation and related methodological topics was convened to address the feasibility and study design issues for the development of a multisite trial of cognitive remediation in schizophrenia called the Cognitive Remediation in the Schizophrenia Trials Network study. This report details the findings from this meeting, which included the following 4 conclusions. (1) A multisite trial of a cognitive remediation intervention using a network of diverse research sites would be of great scientific value. (2) Various interventions could be employed for this multisite trial. (3) Programs that do not address key motivational and interpersonal aspects of cognitive remediation may benefit from supplementation with “bridging groups” that allows patients to meet with others and to apply their newly acquired cognitive skills to everyday life. (4) Before a multisite efficacy trial is initiated, a pilot study could demonstrate the feasibility of conducting a trial using a cognitive remediation intervention. PMID:20194249

  20. Combined remediation technologies: results from field trials at chlorinated solvent impacted sites

    NASA Astrophysics Data System (ADS)

    O'Carroll, D. M.; Chowdhury, A. I.; Lomheim, L.; Boparai, H. K.; Weber, K.; Austrins, L. M.; Edwards, E.; Sleep, B.; de Boer, C. V.; Garcia, A. N.

    2015-12-01

    Non-aqueous phase liquids (NAPLs) are one class of waste liquids often generated from waste mixtures in industrial processes containing surfactants, chlorinated hydrocarbons and other compounds. Chlorinated solvents, a particularly persistent NAPL contaminant, frequently contaminate water sources for decades and are one of the more common contaminants at brownfield and industrialized sites. Although considerable advances in our understanding of the phenomena governing NAPL remediation have been made, and a number of innovative remediation technologies have been developed, existing technologies are rarely able to achieve clean up goals in contaminated aquifers at the completion of remedial activities. The development and pilot scale testing of new and innovative remediation technologies is, therefore, crucial to achieve clean up goals at contaminated sites. Our research group is currently investigating a number of innovative remediation technologies, either individually or as combined remedies. This includes the applicability of nanometals and ISCO (e.g., persulfate) for contaminated site remediation. These technologies can be combined with technologies to enhance amendment delivery (e.g., electrokinetics) or create conditions favorable for enhanced biotic contaminant degradation. This presentation will discuss outcomes from a number of field trials conducted at chlorinated solvent impacted sites by our group with a particular focus on combined remediation technologies.

  1. Polyphosphate Remediation Technology for In-Situ Stabilization of Uranium

    SciTech Connect

    Wellman, Dawn M.; Pierce, Eric M.; Bacon, Diana H.; Fruchter, Jonathan S.; Vermeul, Vincent R.; Webb, Samuel M.

    2009-03-01

    A labortory testing program has been conducted to optimize polyphosphate remediation technology for implementation through a field-scale technology infiltration demonstration to stabilize soluble, uranium-bearing source phases in the vadose zone and capillary fringe. Source treatment in the deep vadose zone will accelerate the natural attenuation of uranium to more thermodynamically stable uranium-phosphate minerals, enhancing the performance of the proposed polyphosphate remediation within the 300 Area aquifer. The objective of this investigation was to develop polyphosphate remediation technology to treat uranium contamination contained within the deep vadose zone and capillary fringe. This paper presents the results of an investigation that evaluated the rate and extent of reaction between polyphosphate and the uranium mineral phases present within the 300 Area vadose zone and capillary fringe and autunite formation as a function of polyphosphate formulation and concentration. This information is critical for identifying the optimum implementation approach and controlling the flux of uranium from the vadose zone and capillary fringe to the underlying aquifer during remediation. Results from this investigation will be used to design a full-scale remediation of uranium at the 300 Area of the Hanford Site.

  2. Remediation of soils combining soil vapor extraction and bioremediation: benzene.

    PubMed

    Soares, António Alves; Albergaria, José Tomás; Domingues, Valentina Fernandes; Alvim-Ferraz, Maria da Conceição M; Delerue-Matos, Cristina

    2010-08-01

    This work reports the study of the combination of soil vapor extraction (SVE) with bioremediation (BR) to remediate soils contaminated with benzene. Soils contaminated with benzene with different water and natural organic matter contents were studied. The main goals were: (i) evaluate the performance of SVE regarding the remediation time and the process efficiency; (ii) study the combination of both technologies in order to identify the best option capable to achieve the legal clean up goals; and (iii) evaluate the influence of soil water content (SWC) and natural organic matter (NOM) on SVE and BR. The remediation experiments performed in soils contaminated with benzene allowed concluding that: (i) SVE presented (a) efficiencies above 92% for sandy soils and above 78% for humic soils; (b) and remediation times from 2 to 45 h, depending on the soil; (ii) BR showed to be an efficient technology to complement SVE; (iii) (a) SWC showed minimum impact on SVE when high airflow rates were used and led to higher remediation times for lower flow rates; (b) NOM as source of microorganisms and nutrients enhanced BR but hindered the SVE due the limitation on the mass transfer of benzene from the soil to the gas phase.

  3. Natural attenuation software (NAS): Assessing remedial strategies and estimating timeframes

    USGS Publications Warehouse

    Mendez, E.; Widdowson, M.; Chapelle, F.; Casey, C.

    2005-01-01

    Natural Attenuation Software (NAS) is a screening tool to estimate remediation timeframes for monitored natural attenuation (MNA) and to assist in decision-making on the level of source zone treatment in conjunction with MNA using site-specific remediation objectives. Natural attenuation processes that NAS models include are advection, dispersion, sorption, non-aqueous phase liquid (NAPL) dissolution, and biodegradation of either petroleum hydrocarbons or chlorinated ethylenes. Newly-implemented enhancements to NAS designed to maximize the utility of NAS for site managers were observed. NAS has expanded source contaminant specification options to include chlorinated ethanes and chlorinated methanes, and to allow for the analysis of any other user-defined contaminants that may be subject to microbially-mediated transformations (heavy metals, radioisotopes, etc.). Included is the capability to model co-mingled plumes, with constituents from multiple contaminant categories. To enable comparison of remediation timeframe estimates between MNA and specific engineered remedial actions , NAS was modified to incorporate an estimation technique for timeframes associated with pump-and-treat remediation technology for comparison to MNA. This is an abstract of a paper presented at the 8th International In Situ and On-Site Bioremediation Symposium (Baltimore, MD 6/6-9/2005).

  4. Cognitive remediation and vocational rehabilitation.

    PubMed

    McGurk, Susan R; Wykes, Til

    2008-01-01

    Persons with severe mental illness (SMI) who are striving to improve their work prospects are often hindered in work endeavors because of difficulties with cognitive skills, such as paying attention or concentrating, learning and remembering information, responding in a reasonable amount of time to environmental demands, and planning ahead and solving problems. In addition to limiting work functioning, cognitive impairments are obstacles to receiving the full benefits of vocational rehabilitation, including supported employment. Efforts to improve cognition in people with SMI, or cognitive remediation, have produced modest but consistent gains in a variety of cognitive domains. More recent efforts have focused on combining cognitive remediation with vocational rehabilitation in order to improve work functioning. Initial results from four published studies of combined cognitive remediation and vocational programs are encouraging, indicating improvements in both cognitive and work functioning. The approaches to cognitive remediation used in these studies vary considerably, as do the characteristics of participants, the vocational rehabilitation models, and the methods of combining cognitive and vocational therapies. The differences in key components of programs combining cognitive remediation and vocational rehabilitation indicate the need to replicate findings, and raise important questions about what aspects of the programs are associated with improvements in work.

  5. Halogenated solvent remediation

    DOEpatents

    Sorenson, Kent S.

    2004-08-31

    Methods for enhancing bioremediation of ground water contaminated with nonaqueous halogenated solvents are disclosed. A preferred method includes adding a composition to the ground water wherein the composition is an electron donor for microbe-mediated reductive dehalogenation of the halogenated solvents and enhances mass transfer of the halogenated solvents from residual source areas into the aqueous phase of the ground water. Illustrative compositions effective in these methods include surfactants such as C.sub.2 -C.sub.4 carboxylic acids and hydroxy acids, salts thereof, esters of C.sub.2 -C.sub.4 carboxylic acids and hydroxy acids, and mixtures thereof. Especially preferred compositions for use in these methods include lactic acid, salts of lactic acid, such as sodium lactate, lactate esters, and mixtures thereof. The microbes are either indigenous to the ground water, or such microbes can be added to the ground water in addition to the composition.

  6. Halogenated solvent remediation

    DOEpatents

    Sorenson, Jr., Kent S.

    2008-11-11

    Methods for enhancing bioremediation of ground water contaminated with nonaqueous halogenated solvents are disclosed. An illustrative method includes adding an electron donor for microbe-mediated anaerobic reductive dehalogenation of the halogenated solvents, which electron donor enhances mass transfer of the halogenated solvents from residual source areas into the aqueous phase of the ground water. Illustrative electron donors include C.sub.2-C.sub.4 carboxylic acids and hydroxy acids, salts thereof, esters of C.sub.2-C.sub.4 carboxylic acids and hydroxy acids, and mixtures thereof, of which lactic acid, salts of lactic acid--such as sodium lactate, lactate esters, and mixtures thereof are particularly illustrative. The microbes are either indigenous to the ground water, or such microbes can be added to the ground water in addition to the electron donor.

  7. Remedial Action Contacts Directory - 1997

    SciTech Connect

    1997-05-01

    This document, which was prepared for the US Department of Energy (DOE) Office of Environmental Restoration (ER), is a directory of 2628 individuals interested or involved in environmental restoration and/or remedial actions at radioactively contaminated sites. This directory contains a list of mailing addresses and phone numbers of DOE operations, area, site, project, and contractor offices; an index of DOE operations, area, site, project, and contractor office sorted by state; a list of individuals, presented by last name, facsimile number, and e-mail address; an index of affiliations presented alphabetically, with individual contacts appearing below each affiliation name; and an index of foreign contacta sorted by country and affiliation. This document was generated from the Remedial Action Contacts Database, which is maintained by the Remedial Action Program Information Center (RAPIC).

  8. Bioelectrical Perchlorate Remediation

    NASA Astrophysics Data System (ADS)

    Thrash, C.; Achenbach, L. A.; Coates, J. D.

    2007-12-01

    low-level perchlorate (100 μg.L-1) influent as well as mixed-waste influents more typically found in the environment containing both nitrate and perchlorate. Through extended periods of operation (>70 days), no loss in treatment efficiency was noted and no measurable growth in biomass was observed. Gas phase analysis indicated that low levels of H2 produced at the cathode surface through electrolysis can provide enough reducing equivalents to mediate this metabolism. The results of these studies demonstrate that perchlorate remediation can be facilitated through the use of a cathode as the primary electron donor, and that continuous treatment in such a system approaches current industry standards. This has important implications for the continuous treatment of this critical contaminant in industrial waste streams and drinking water. Such a process has the advantage of long-term, low-maintenance operation with ease of online monitoring and control while limiting the injection of additional chemicals into the water treatment process and outgrowth of the microbial populations. This would negate the need for the continual removal and disposal of biomass produced during treatment and also the downstream issues associated with corrosion and biofouling of distribution systems and the production of toxic disinfection byproducts.

  9. Remediation Technologies Eliminate Contaminants

    NASA Technical Reports Server (NTRS)

    2012-01-01

    groundwater tainted by chlorinated solvents once used to clean rocket engine components. The award-winning innovation (Spinoff 2010) is now NASA s most licensed technology to date. PCBs in paint presented a new challenge. Removing the launch stand for recycling proved a difficult operation; the toxic paint had to be fully stripped from the steel structure, a lengthy and costly process that required the stripped paint to be treated before disposal. Noting the lack of efficient, environmentally friendly options for dealing with PCBs, Quinn and her colleagues developed the Activated Metal Treatment System (AMTS). AMTS is a paste consisting of a solvent solution containing microscale particles of activated zero-valent metal. When applied to a painted surface, the paste extracts and degrades the PCBs into benign byproducts while leaving the paint on the structure. This provides a superior alternative to other methods for PCB remediation, such as stripping the paint or incinerating the structure, which prevents reuse and can release volatized PCBs into the air. Since its development, AMTS has proven to be a valuable solution for removing PCBs from paint, caulking, and various insulation and filler materials in older buildings, naval ships, and former munitions facilities where the presence of PCBs interferes with methods for removing trace explosive materials. Miles of potentially toxic caulking join sections of runways at airports. Any of these materials installed before 1979 potentially contain PCBs, Quinn says. "This is not just a NASA problem," she says. "It s a global problem."

  10. Research issues for thermal remediation

    SciTech Connect

    Davis, E.L.; Heron, G.

    1998-06-01

    In order to optimize thermal remediation techniques, all of the effects of the heat on the subsurface system must be understood and taken into consideration during the remediation. Research is needed to provide a better understanding of the effects of temperature on capillarity in soils. This should include laboratory data on the effect of temperature on capillarity in soils. This should include laboratory data on the effect of temperature on displacement pressures which is needed to determine the potential for downward movement of DNAPLS.

  11. Multiphase fluid simulation tools for winning remediation solutions

    SciTech Connect

    Deschaine, L.M.

    1997-07-01

    Releases of petroleum product such as gasoline and diesel fuels from normal operating practices to aquifers are common. The costs to remediate these releases can run in the billions of dollars. Solutions to remediate these releases usually consist of some form of multiphase (air, water, oil) fluid movement, whether it be a multiphase high vacuum extraction system, bioslurping, groundwater pump and treat system, an air sparging system, a soil vapor extraction system, a free product recovery system, bioremediation or the like. The software being tested in Test Drive, Multiphase Organic Vacuum Enhanced Recovery Simulator (MOVER) is a computer simulation tool that will give the practitioner the ability to design high vacuum enhanced multiple phase recovery systems and bioslurping systems, which are often the low cost effective remediation approach. It will also allow for the comparison of various proposed remediation approaches and technologies so the best solution can be chosen for a site. This is a key competitive advantage to translate conceptual ideas into winning bids.

  12. High altitude mine waste remediation -- Implementation of the Idarado remedial action plan

    SciTech Connect

    Hardy, A.J.; Redmond, J.V.; River, R.A.; Davis, C.S.

    1999-07-01

    The Idarado Mine in Colorado's San Juan Mountains includes 11 tailing areas, numerous waste rock dumps, and a large number of underground openings connected by over 100 miles of raises and drifts. The tailings and mine wastes were generated from different mining and milling operations between 1975 and 1978. the Idarado Remedial Action Plan (RAP) was an innovative 5-year program developed for remediating the impacts of historic mining activities in the San Miguel River and Red Mountain Creek drainages. The challenges during implementation included seasonal access limitations due to the high altitude construction areas, high volumes of runoff during snow melt, numerous abandoned underground openings and stopped-out veins, and high profile sites adjacent to busy jeep trails and a major ski resort town. Implementation of the RAP has included pioneering efforts in engineering design and construction of remedial measures. Innovative engineering designs included direct revegetation techniques for the stabilization of tailings piles, concrete cutoff walls and French drains to control subsurface flows, underground water controls that included pipelines, weeplines, and portal collection systems, and various underground structures to collect and divert subsurface flows often exceeding 2,000 gpm. Remote work locations have also required the use of innovative construction techniques such as heavy lift helicopters to move construction materials to mines above 10,000 feet. This paper describes the 5-year implementation program which has included over 1,000,000 cubic yards of tailing regrading, application of 5,000 tons of manure and 26,000 tons of limestone, and construction of over 10,000 feet of pipeline and approximately 45,000 feet of diversion channel.

  13. Re/Mediating Adolescent Literacies.

    ERIC Educational Resources Information Center

    Elkins, John, Ed.; Luke, Allan, Ed.

    Suggesting that teaching in New Times requires that educators read and re/mediate the social relations, the cultural knowledges, and the relationships of power between adolescents and their social, biological, and semiotic universes, this collection of essays offers new ways of seeing and talking about adolescents and their literacies. Most of the…

  14. Using specialized adsorbents for remediation

    SciTech Connect

    Hochmuth, D.P.; Grant, A.

    1995-11-01

    This paper describes two remediation case studies in which specialized adsorbents were used. In one case, the adsorbents were used to treat effluent from a soil vapor extraction system. In the other case, the adsorbents were used to treat air from a groundwater air stripper. The specialized adsorbents effectively removed volatile organic compounds from each air stream.

  15. Cooperative Learning for Remedial Students.

    ERIC Educational Resources Information Center

    Stiers, Darlene

    1989-01-01

    Offers cooperative learning instructional techniques for teaching the historical novel "The Root Cellar" in a remedial reading classroom. Recommends cooperative learning as a means through which the student can succeed academically while developing interpersonal skills. Suggests that the lesson can be adapted to match the ability level of…

  16. Toxic Remediation System And Method

    DOEpatents

    Matthews, Stephen M.; Schonberg, Russell G.; Fadness, David R.

    1996-07-23

    What is disclosed is a novel toxic waste remediation system designed to provide on-site destruction of a wide variety of hazardous organic volatile hydrocarbons, including but not limited to halogenated and aromatic hydrocarbons in the vapor phase. This invention utilizes a detoxification plenum and radiation treatment which transforms hazardous organic compounds into non-hazardous substances.

  17. Remediation Technology for Contaminated Groundwater

    EPA Science Inventory

    Bioremediation is the most commonly selected technology for remediation of ground water at Superfund sites in the USA. The next most common technology is Chemical treatment, followed by Air Sparging, and followed by Permeable Reactive Barriers. This presentation reviews the the...

  18. Remedial Mathematics for Quantum Chemistry

    ERIC Educational Resources Information Center

    Koopman, Lodewijk; Brouwer, Natasa; Heck, Andre; Buma, Wybren Jan

    2008-01-01

    Proper mathematical skills are important for every science course and mathematics-intensive chemistry courses rely on a sound mathematical pre-knowledge. In the first-year quantum chemistry course at this university, it was noticed that many students lack basic mathematical knowledge. To tackle the mathematics problem, a remedial mathematics…

  19. Green Chemistry and Environmental Remediation

    EPA Science Inventory

    Abstract: Nutrient remediation and recovery is a growing concern for two key reasons: (i) the prevention of harmful algal bloom proliferation, and (ii) the recycling of nutrients (e.g., phosphates) as they are non-renewable resources which are quickly being depleted. A wide range...

  20. Preferential Remedies for Employment Discrimination

    ERIC Educational Resources Information Center

    Edwards, Harry T.; Zaretsky, Barry L.

    1975-01-01

    An overview of the problem of preferential remedies to achieve equal employment opportunities for women and minority groups. Contends that "color blindness" will not end discrimination but that some form of "color conscious" affirmative action program must be employed. Temporary preferential treatment is justified, according to the author, by the…

  1. Rethinking Diversity.

    ERIC Educational Resources Information Center

    Gordon, Jack

    1992-01-01

    Managing diversity is about coping with unassimilated differences, about building systems and a culture that unite different people in a common pursuit without undermining their diversity. The goal of diversity training is a high performance organization rather than a climate in which no one's feathers are ruffled. (SK)

  2. Review of remediation practices regarding cadmium-enriched farmland soil with particular reference to China.

    PubMed

    Tang, X; Li, Q; Wu, M; Lin, L; Scholz, M

    2016-10-01

    Cadmium-enrichment of farmland soil greatly threatens the sustainable use of soil resources and the safe cultivation of grain. This review paper briefly introduces the status of farmland soil as well as grain, which are both often polluted by cadmium (Cd) in China, and illustrates the major sources of Cd contaminants in farmland soil. In order to meet soil environmental quality standards and farmland environmental quality evaluation standards for edible agricultural products, Cd-enriched farmland soil is frequently remediated with the following prevailing techniques: dig and fill, electro-kinetic remediation, chemical elution, stabilisation and solidification, phytoremediation, field management and combined remediation. Most remediation techniques are still at the stage of small-scale trial experiments in China and few techniques are assessed in field trials. After comparing the technical and economical applicability among different Cd-enriched farmland soil remediation techniques, a novel ecological and hydraulic remediation technique has been proposed, which integrated the advantages of chemical elution, solidification and stabilisation, phytoremediation and field management. The ecological and hydraulic remediation concept is based on existing irrigation and drainage facilities, ecological ditches (ponds) and agronomic measures, which mainly detoxify the Cd-enriched soil during the interim period of crop cultivation, and guarantee the grain safety during its growth period. This technique may shift the challenge from soil to water treatment, and thus greatly enhances the remediation efficiency and shortens the remediation duration. Moreover, the proposed ecological and hydraulic remediation method matches well with the practical choice of cultivation while remediation for Cd-enriched soil in China, which has negligible impacts on the normal crop cultivation process, and thus shows great potential for large area applications. PMID:27562701

  3. Review of remediation practices regarding cadmium-enriched farmland soil with particular reference to China.

    PubMed

    Tang, X; Li, Q; Wu, M; Lin, L; Scholz, M

    2016-10-01

    Cadmium-enrichment of farmland soil greatly threatens the sustainable use of soil resources and the safe cultivation of grain. This review paper briefly introduces the status of farmland soil as well as grain, which are both often polluted by cadmium (Cd) in China, and illustrates the major sources of Cd contaminants in farmland soil. In order to meet soil environmental quality standards and farmland environmental quality evaluation standards for edible agricultural products, Cd-enriched farmland soil is frequently remediated with the following prevailing techniques: dig and fill, electro-kinetic remediation, chemical elution, stabilisation and solidification, phytoremediation, field management and combined remediation. Most remediation techniques are still at the stage of small-scale trial experiments in China and few techniques are assessed in field trials. After comparing the technical and economical applicability among different Cd-enriched farmland soil remediation techniques, a novel ecological and hydraulic remediation technique has been proposed, which integrated the advantages of chemical elution, solidification and stabilisation, phytoremediation and field management. The ecological and hydraulic remediation concept is based on existing irrigation and drainage facilities, ecological ditches (ponds) and agronomic measures, which mainly detoxify the Cd-enriched soil during the interim period of crop cultivation, and guarantee the grain safety during its growth period. This technique may shift the challenge from soil to water treatment, and thus greatly enhances the remediation efficiency and shortens the remediation duration. Moreover, the proposed ecological and hydraulic remediation method matches well with the practical choice of cultivation while remediation for Cd-enriched soil in China, which has negligible impacts on the normal crop cultivation process, and thus shows great potential for large area applications.

  4. 49 CFR 193.2637 - Remedial measures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Remedial measures. 193.2637 Section 193.2637 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY...: FEDERAL SAFETY STANDARDS Maintenance § 193.2637 Remedial measures. Prompt corrective or remedial...

  5. 49 CFR 193.2637 - Remedial measures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Remedial measures. 193.2637 Section 193.2637 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY...: FEDERAL SAFETY STANDARDS Maintenance § 193.2637 Remedial measures. Prompt corrective or remedial...

  6. 40 CFR 85.1803 - Remedial Plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Remedial Plan. 85.1803 Section 85.1803... POLLUTION FROM MOBILE SOURCES Recall Regulations § 85.1803 Remedial Plan. (a) When any manufacturer is... manufacturer shall submit a plan to the Administrator to remedy such nonconformity. The plan shall contain...

  7. 40 CFR 92.705 - Remedial plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Remedial plan. 92.705 Section 92.705... POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Recall Regulations § 92.705 Remedial plan. (a) When any... manufacturer or remanufacturer shall submit a plan to the Administrator to remedy such nonconformity. The...

  8. 40 CFR 85.1803 - Remedial Plan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Remedial Plan. 85.1803 Section 85.1803... POLLUTION FROM MOBILE SOURCES Recall Regulations § 85.1803 Remedial Plan. (a) When any manufacturer is... manufacturer shall submit a plan to the Administrator to remedy such nonconformity. The plan shall contain...

  9. 40 CFR 85.1803 - Remedial Plan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Remedial Plan. 85.1803 Section 85.1803... POLLUTION FROM MOBILE SOURCES Recall Regulations § 85.1803 Remedial Plan. (a) When any manufacturer is... manufacturer shall submit a plan to the Administrator to remedy such nonconformity. The plan shall contain...

  10. 40 CFR 92.705 - Remedial plan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Remedial plan. 92.705 Section 92.705... POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Recall Regulations § 92.705 Remedial plan. (a) When any... manufacturer or remanufacturer shall submit a plan to the Administrator to remedy such nonconformity. The...

  11. 40 CFR 92.705 - Remedial plan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Remedial plan. 92.705 Section 92.705... POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Recall Regulations § 92.705 Remedial plan. (a) When any... manufacturer or remanufacturer shall submit a plan to the Administrator to remedy such nonconformity. The...

  12. ELECTROCHEMICAL REMEDIATION TECHNOLOGIES (ECRTS) DEMONSTRATION BULLETIN

    EPA Science Inventory

    The ElectroChemical Remediation Technologies (ECRTs) process was developed by P2-Soil Remediation, Inc. P-2 Soil Remediation, Inc. formed a partnership with Weiss Associates and ElectroPetroleum, Inc. to apply the technology to contaminated sites. The ECRTs process was evaluated ...

  13. Remediation: Higher Education's Bridge to Nowhere

    ERIC Educational Resources Information Center

    Complete College America, 2012

    2012-01-01

    The intentions were noble. It was hoped that remediation programs would be an academic bridge from poor high school preparation to college readiness. Sadly, remediation has become instead higher education's "Bridge to Nowhere." This broken remedial bridge is travelled by some 1.7 million beginning students each year, most of whom will…

  14. 45 CFR 77.4 - Remedial actions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Remedial actions. 77.4 Section 77.4 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION REMEDIAL ACTIONS APPLICABLE TO LETTER OF CREDIT ADMINISTRATION § 77.4 Remedial actions. If, after the conclusion of the procedures set forth...

  15. Removing Remediation Requirements: Effectiveness of Intervention Programs

    ERIC Educational Resources Information Center

    Fine, Anne; Duggan, Mickle; Braddy, Linda

    2009-01-01

    Remediation of incoming college freshman students is a national concern because remediated students are at higher risk of failing to complete their degrees. Some Oklahoma higher education institutions are working to assist K-12 systems in finding ways to reduce the number of incoming college freshman students requiring remediation. This study…

  16. GROUNDWATER REMEDIATION SOLUTIONS AT HANFORD

    SciTech Connect

    Gilmore, Tyler J.; Truex, Michael J.; Williams, Mark D.

    2007-02-26

    In 2006, Congress provided funding to the U. S. Department of Energy (DOE) to study new technologies that could be used to treat contamination from the Hanford Site that might impact the Columbia River. The contaminants of concern are primarily metals and radionuclides, which are byproducts of Hanford’s cold war mission to produce plutonium for atomic weapons. The DOE asked Pacific Northwest National Laboratory (PNNL) to consider this problem and develop approaches to address the contamination that threatens the river. DOE identified three high priority sites that had groundwater contamination migrating towards the Columbia river for remediation. The contaminants included strontium-90, uranium and chromium. Remediation techniques for metals and radionuclides focus primarily on altering the oxidation state of the contaminant chemically or biologically, isolating the contaminants from the environment through adsorption or encapsulation or concentrating the contaminants for removal. A natural systems approach was taken that uses a mass balance concept to frame the problem and determine the most appropriate remedial approach. This approach provides for a scientifically based remedial decision. The technologies selected to address these contaminants included an apatite adsorption barrier coupled with a phytoremediation to address the strontium-90 contamination, injection of polyphosphate into the subsurface to sequester uranium, and a bioremediation approach to reduce chromium contamination in the groundwater. The ability to provide scientifically based approaches is in large part due to work developed under previous DOE Office of Science and Office of Environmental Management projects. For example, the polyphosphate and the bioremediation techniques, were developed by PNNL under the EMSP and NABIR programs. Contaminated groundwater under the Hanford Site poses a potential risk to humans and the Columbia River. These new technologies holds great promise for

  17. 13 CFR 108.1810 - Events of default and SBA's remedies for NMVC Company's noncompliance with terms of Debentures.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... substantive regulation promulgated under the Act. (9) Failure to maintain diversity. You fail to maintain diversity between management and ownership as required by § 108.150. (g) SBA remedies for events of default... section. (1) Excessive Management Expenses. Without the prior written consent of SBA, you incur...

  18. 13 CFR 108.1810 - Events of default and SBA's remedies for NMVC Company's noncompliance with terms of Debentures.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... substantive regulation promulgated under the Act. (9) Failure to maintain diversity. You fail to maintain diversity between management and ownership as required by § 108.150. (g) SBA remedies for events of default... section. (1) Excessive Management Expenses. Without the prior written consent of SBA, you incur...

  19. Y-12 Plant Remedial Action technology logic diagram. Volume I: Technology evaluation

    SciTech Connect

    1994-09-01

    The Y-12 Plant Remedial Action Program addresses remediation of the contaminated groundwater, surface water and soil in the following areas located on the Oak Ridge Reservation: Chestnut Ridge, Bear Creek Valley, the Upper and Lower East Fork Popular Creek Watersheds, CAPCA 1, which includes several areas in which remediation has been completed, and CAPCA 2, which includes dense nonaqueous phase liquid wells and a storage facility. There are many facilities within these areas that are contaminated by uranium, mercury, organics, and other materials. This Technology Logic Diagram identifies possible remediation technologies that can be applied to the soil, water, and contaminants for characterization, treatment, and waste management technology options are supplemented by identification of possible robotics or automation technologies. These would facilitate the cleanup effort by improving safety, of remediation, improving the final remediation product, or decreasing the remediation cost. The Technology Logic Diagram was prepared by a diverse group of more than 35 scientists and engineers from across the Oak Ridge Reservation. Most are specialists in the areas of their contributions. 22 refs., 25 tabs.

  20. A coupled simulation-optimization approach for groundwater remediation design under uncertainty: an application to a petroleum-contaminated site.

    PubMed

    He, L; Huang, G H; Lu, H W

    2009-01-01

    This study provides a coupled simulation-optimization approach for optimal design of petroleum-contaminated groundwater remediation under uncertainty. Compared to the previous approaches, it has the advantages of: (1) addressing the stochasticity of the modeling parameters in simulating the flow and transport of NAPLs in groundwater, (2) providing a direct and response-rapid bridge between remediation strategies (pumping rates) and remediation performance (contaminant concentrations) through the created proxy models, (3) alleviating the computational cost in searching for optimal solutions, and (4) giving confidence levels for the obtained optimal remediation strategies. The approach is applied to a practical site in Canada for demonstrating its performance. The results show that mitigating the effects of uncertainty on optimal remediation strategies (through enhancing the confidence level) would lead to the rise of remediation cost due to the increase in the total pumping rate.

  1. Southern leaf blight disease severity is correlated with decreased maize leaf epiphytic bacterial species richness and the phyllosphere bacterial diversity decline is enhanced by nitrogen fertilization

    PubMed Central

    Manching, Heather C.; Balint-Kurti, Peter J.; Stapleton, Ann E.

    2014-01-01

    Plant leaves are inhabited by a diverse group of microorganisms that are important contributors to optimal growth. Biotic and abiotic effects on plant growth are usually studied in controlled settings examining response to variation in single factors and in field settings with large numbers of variables. Multi-factor experiments with combinations of stresses bridge this gap, increasing our understanding of the genotype-environment-phenotype functional map for the host plant and the affiliated epiphytic community. The maize inbred B73 was exposed to single and combination abiotic and the biotic stress treatments: low nitrogen fertilizer and high levels of infection with southern leaf blight (causal agent Cochliobolus heterostrophus). Microbial epiphyte samples were collected at the vegetative early-season phase and species composition was determined using 16S ribosomal intergenic spacer analysis. Plant traits and level of southern leaf blight disease were measured late-season. Bacterial diversity was different among stress treatment groups (P < 0.001). Lower species richness—alpha diversity—was correlated with increased severity of southern leaf blight disease when disease pressure was high. Nitrogen fertilization intensified the decline in bacterial alpha diversity. While no single bacterial ribotype was consistently associated with disease severity, small sets of ribotypes were good predictors of disease levels. Difference in leaf bacterial-epiphyte diversity early in the season were correlated with plant disease severity, supporting further tests of microbial epiphyte-disease correlations for use in predicting disease progression. PMID:25177328

  2. Using C-Span in the Classroom to Enhance Student Analysis of Ross Perot's Sensitivity with American Diversity During the 1992 Presidential Campaign

    ERIC Educational Resources Information Center

    Schnell, James

    2007-01-01

    The C-SPAN application to be described in this article is useful in the Cross-Cultural Communication and Mass Media courses. This application focuses on how we define what connotes sensitivity & insensitivity with diversity issues and how journalistic interpretation can affect our perception via mass media. Businessman Ross Perot rose from…

  3. Enhancing Preservice Teachers' Sense of Efficacy and Attitudes toward School Diversity through Preparation: A Case of One U.S. Inclusive Teacher Education Program

    ERIC Educational Resources Information Center

    Gao, Wei; Mager, Gerald

    2011-01-01

    Conducted in one inclusive teacher education program in the United States, this study explored the trajectory of and the relationships between preservice teachers' sense of efficacy and attitudes toward school diversity through the course of preparation. Findings revealed that, in general, changes of preservice teachers' perceived efficacy,…

  4. The Study of an Intervention Summer Bridge Program Learning Community: Remediation, Retention, and Graduation

    ERIC Educational Resources Information Center

    McEvoy, Suzanne

    2012-01-01

    With the changing U.S. demographics, higher numbers of diverse, low-income, first-generation students are underprepared for the academic rigors of four-year institutions oftentimes requiring assistance, and remedial and/or developmental coursework in English and mathematics. Without intervention approaches these students are at high risk for…

  5. Enhancing bioremediation

    SciTech Connect

    Koenigsberg, S.

    1997-02-01

    Oxygen is often the limiting factor in aerobic bioremediation. Without adequate oxygen, contaminant degradation will either cease or proceed by highly inefficient anaerobic processes. Researchers at Regenesis Bioremediation Products recently develope a technology to combat this problem, Oxygen Release Compound (ORC) a unique formulation of magnesium peroxide release oxygen slowly when hydrated. ORC is idea for supporting bioremediation of underground storage tank releases. ORC treatment represents a low intensity approach to remediation - simple, passive, low-cost, long term enhancement of a natural attenuation. 1 fig.

  6. THERMAL TECHNIQUES FOR THE IN-SITU CHARACTERIZATION AND REMEDIATION OF MERCURY: INSIGHTS FROM DEPLOYMENT OF THE MEMBRANE INTERFACE PROBE

    SciTech Connect

    Jackson, Dennis; Looney, Brian; Eddy-Dilek, Carol A.

    2013-08-07

    This presentation focuses on how thermal energy can effectively be used to enhance characterization, promote the remediation, and aid in delivering a sequestering agent to stabilize elemental mercury in subsurface soils. Slides and speaker notes are provided.

  7. Remediation plans in family medicine residency

    PubMed Central

    Audétat, Marie-Claude; Voirol, Christian; Béland, Normand; Fernandez, Nicolas; Sanche, Gilbert

    2015-01-01

    Abstract Objective To assess use of the remediation instrument that has been implemented in training sites at the University of Montreal in Quebec to support faculty in diagnosing and remediating resident academic difficulties, to examine whether and how this particular remediation instrument improves the remediation process, and to determine its effects on the residents’ subsequent rotation assessments. Design A multimethods approach in which data were collected from different sources: remediation plans developed by faculty, program statistics for the corresponding academic years, and students’ academic records and rotation assessment results. Setting Family medicine residency program at the University of Montreal. Participants Family medicine residents in academic difficulty. Main outcome measures Assessment of the content, process, and quality of remediation plans, and students’ academic and rotation assessment results (successful, below expectations, or failure) both before and after the remediation period. Results The framework that was developed for assessing remediation plans was used to analyze 23 plans produced by 10 teaching sites for 21 residents. All plans documented cognitive problems and implemented numerous remediation measures. Although only 48% of the plans were of good quality, implementation of a remediation plan was positively associated with the resident’s success in rotations following the remediation period. Conclusion The use of remediation plans is well embedded in training sites at the University of Montreal. The residents’ difficulties were mainly cognitive in nature, but this generally related to deficits in clinical reasoning rather than knowledge gaps. The reflection and analysis required to produce a remediation plan helps to correct many academic difficulties and normalize the academic career of most residents in difficulty. Further effort is still needed to improve the quality of plans and to support teachers.

  8. Progress in remediation of groundwater at petroleum sites in California.

    PubMed

    McHugh, Thomas E; Kulkarni, Poonam R; Newell, Charles J; Connor, John A; Garg, Sanjay

    2014-01-01

    Quantifying the overall progress in remediation of contaminated groundwater has been a significant challenge. We utilized the GeoTracker database to evaluate the progress in groundwater remediation from 2001 to 2011 at over 12,000 sites in California with contaminated groundwater. This paper presents an analysis of analytical results from over 2.1 million groundwater samples representing at least $100 million in laboratory analytical costs. Overall, the evaluation of monitoring data shows a large decrease in groundwater concentrations of gasoline constituents. For benzene, half of the sites showed a decrease in concentration of 85% or more. For methyl tert-butyl ether (MTBE), this decrease was 96% and for TBE, 87%. At remediation sites in California, the median source attenuation rate was 0.18/year for benzene and 0.36/year for MTBE, corresponding to half-lives of 3.9 and 1.9 years, respectively. Attenuation rates were positive (i.e., decreasing concentration) for benzene at 76% of sites and for MTBE at 85% of sites. An evaluation of sites with active remediation technologies suggests differences in technology effectiveness. The median attenuation rates for benzene and MTBE are higher at sites with soil vapor extraction or air sparging compared with sites without these technologies. In contrast, there was little difference in attenuation rates at sites with or without soil excavation, dual phase extraction, or in situ enhanced biodegradation. The evaluation of remediation technologies, however, did not evaluate whether specific systems were well designed or implemented and did not control for potential differences in other site factors, such as soil type.

  9. ORNL Remedial Action Program strategy (FY 1987-FY 1992)

    SciTech Connect

    Trabalka, J.R.; Myrick, T.E.

    1987-12-01

    Over 40 years of Oak Ridge National Laboratory (ORNL) operations have produced a diverse legacy of contaminated inactive facilities, research areas, and waste disposal areas that are potential candidates for remedial action. The ORNL Remedial Action Program (RAP) represents a comprehensive effort to meet new regulatory requirements and ensure adequate protection of on-site workers, the public, and the environment by providing appropriate corrective measures at over 130 sites contaminated historically with radioactive, hazardous chemical, or mixed wastes. A structured path of program planning, site characterization, alternatives assessment, technology development, engineering design, continued site maintenance and surveillance, interim corrective action, and eventual site closure or decommissioning is required to meet these objectives. This report documents the development of the Remedial Action Program, through its preliminary characterization, regulatory interface, and strategy development activities. It provides recommendations for a comprehensive, long-term strategy consistent with existing technical, institutional, and regulatory information, along with a six-year plan for achieving its initial objectives. 53 refs., 8 figs., 12 tabs.

  10. Program overview: Remedial actions at Oak Ridge National Laboratory

    SciTech Connect

    Bates, L.D.; Trabalka, J.R.

    1988-07-27

    Research on and development of civilian and defense uses of nuclear materials and technologies have occurred at Oak Ridge National Laboratory (ORNL) since its creation as part of the World War II Manhattan Project in 1943. A diverse legacy of contaminated inactive facilities, research areas, and waste management areas exists; many are candidates for remedial action. Most attention is focused on waste management sites which contain the bulk of ORNL's environmental contamination. A wide variety of liquid and solid wastes, primarily radioactive wastes or mixed wastes in which radioactivity was the principal hazardous constituent, have been disposed of on-site in the past 45 years. One potential approach to remedial problems at ORNL is to design primarily for control and decay in situ (during an institutional control period of 100 years or more) of intermediate-lived wastes such as /sup 3/H, /sup 90/Sr, and /sup 137/Cs. Passive measures designed to provide greater long-term confinement (for example, in situ vitrification) could be exercised at sites contaminated with TRU wastes or high concentrations of hazardous constitutes. This approach would (a) provide a period sufficiently long for evaluation of the effectiveness of environmental processes and passive remedial measures in controlling the migration of long-lived materials, (b) allow additional time needed for development of new technologies for more permanent site stabilization, and (c) reduce the need for immediate implementation of the more-expensive exhumation and disposal option.

  11. Electroosmosis remediation of DNAPLS in low permeability soils

    SciTech Connect

    Ho, S V.

    1996-08-01

    Electroosmosis is the movement of water through a soil matrix induced by a direct current (DC) electric field. The technique has been used since the 1930s for dewatering and stabilizing fine-grained soils. More recently, electroosmosis has been considered as an in-situ method for soil remediation in which water is injected into the soil at the anode region to flush the contaminants to the cathode side for further treatment or disposal. The major advantage of electroosmosis is its inherent ability to move water uniformly through clayey, silty soils at 100 to 1000 times faster than attainable by hydraulic means, and with very low energy usage. Drawbacks of electroosmosis as a stand-alone technology include slow speed, reliance on solubilizing the contaminants into the groundwater for removal, potentially an unstable process for long term operation, and necessary additional treatment and disposal of the collected liquid. Possible remediation applications of electroosmosis for DNAPLs would be primarily in the removal of residual DNAPLs in the soil pores by electroosmotic flushing. The future of electroosmosis as a broad remedial method lies in how well it can be coupled with complementary technologies. Examples include combining electroosmosis with vacuum extraction, with surfactant usage to deal with non-aqueous phase liquids (NAPLs) through enhanced solubilization or mobilization, with permeability enhancing methods (hydrofracturing, pneumatic fracturing, etc.) to create recovery zones, and with in-situ degradation zones to eliminate aboveground treatment. 33 refs., 1 fig., 1 tab.

  12. A randomized study of cognitive remediation for forensic and mental health patients with schizophrenia.

    PubMed

    Ahmed, Anthony O; Hunter, Kristin M; Goodrum, Nada M; Batten, Nancy-Jane; Birgenheir, Denis; Hardison, Erik; Dixon, Thaddeus; Buckley, Peter F

    2015-09-01

    Cognitive remediation has proven efficacy for improving neurocognition in people with schizophrenia. The current study evaluated the benefits of cognitive remediation on neurocognition, functioning, psychotic symptoms, and aggression in a sample of forensic and mental health patients. Care recipients with schizophrenia or schizoaffective disorder (N = 78) receiving services in the forensic and mental health units of a state hospital were randomized to participate in cognitive remediation versus computer games control activities. Participants' neurocognition, functional capacity, experiential recovery, psychotic symptoms, and aggression incidents were assessed at baseline and posttreatment. Cognitive remediation was associated with improvements in several neurocognitive domains and circumscribed domains of functional capacity. People assigned to cognitive remediation experiences greater reductions in negative symptoms, agitation/excitement, and verbal and physical aggression. In addition to improving neurocognition in long-term hospitalized forensic and mental health patients, cognitive remediation may enhance efforts at reducing negative symptoms, emotion dysregulation, and aggression incidents. Forensic settings may represent a new frontier for the clinical dissemination of cognitive remediation.

  13. Documenting cost and performance for environmental remediation projects: Department of Energy Office of Environmental Management

    SciTech Connect

    1996-08-08

    The purpose of this DOE guide is to facilitate the use of consistent procedures to document cost and performance information for projects involving the remediation of media contaminated with hazardous and radioactive wastes. It provides remedial action project managers with a standardized set of data to document completed remediation projects. Standardized reporting of data will broaden the utility of the information, increase confidence in the effectiveness of future remedial technologies, and enhance the organization, storage and retrieval of relevant information for future cleanup projects. The foundation for this guide was laid down by the Federal Remediation Technologies Roundtable (FRTR) in their publication, Guide to Documenting Cost and Performance for Remediation Projects, EPA-542-B- 95-002. Member agencies of the FRTR include the US EPA, the US DOD, the US DOE, and the US DOI. All the member agencies are involved in site remediation projects and anticipate following the guidance provided in the above reference. Therefore, there is much to be gained for DOE to be consistent with the other member agencies as it will be easier to compare projects across different agencies and also to learn from the experiences of a wider spectrum of prior completed projects.

  14. A randomized study of cognitive remediation for forensic and mental health patients with schizophrenia.

    PubMed

    Ahmed, Anthony O; Hunter, Kristin M; Goodrum, Nada M; Batten, Nancy-Jane; Birgenheir, Denis; Hardison, Erik; Dixon, Thaddeus; Buckley, Peter F

    2015-09-01

    Cognitive remediation has proven efficacy for improving neurocognition in people with schizophrenia. The current study evaluated the benefits of cognitive remediation on neurocognition, functioning, psychotic symptoms, and aggression in a sample of forensic and mental health patients. Care recipients with schizophrenia or schizoaffective disorder (N = 78) receiving services in the forensic and mental health units of a state hospital were randomized to participate in cognitive remediation versus computer games control activities. Participants' neurocognition, functional capacity, experiential recovery, psychotic symptoms, and aggression incidents were assessed at baseline and posttreatment. Cognitive remediation was associated with improvements in several neurocognitive domains and circumscribed domains of functional capacity. People assigned to cognitive remediation experiences greater reductions in negative symptoms, agitation/excitement, and verbal and physical aggression. In addition to improving neurocognition in long-term hospitalized forensic and mental health patients, cognitive remediation may enhance efforts at reducing negative symptoms, emotion dysregulation, and aggression incidents. Forensic settings may represent a new frontier for the clinical dissemination of cognitive remediation. PMID:26228394

  15. Remediation tradeoffs addressed with simulated annealing optimization

    SciTech Connect

    Rogers, L. L., LLNL

    1998-02-01

    Escalation of groundwater remediation costs has encouraged both advances in optimization techniques to balance remediation objectives and economics and development of innovative technologies to expedite source region clean-ups. We present an optimization application building on a pump-and-treat model, yet assuming a prior removal of different portions of the source area to address the evolving management issue of more aggressive source remediation. Separate economic estimates of in-situ thermal remediation are combined with the economic estimates of the subsequent optimal pump-and-treat remediation to observe tradeoff relationships of cost vs. highest remaining contamination levels (hot spot). The simulated annealing algorithm calls the flow and transport model to evaluate the success of a proposed remediation scenario at a U.S.A. Superfund site contaminated with volatile organic compounds (VOCs).

  16. [Natural remedies during pregnancy and lactation].

    PubMed

    Gut, E; Melzer, J; von Mandach, U; Saller, R

    2004-10-01

    Up to date there is a lack of systematically gathered data on the use of natural remedies (phytotherapeutic, homeopathic, anthroposophic, spagyric, Bach and Schussler remedies) during pregnancy and lactation. The aim of this non-representative pilot study on 139 women, who came for delivery to three institutions between mid-1997 and the beginning of 1998, was to receive data about how often and within which spectrum natural remedies are used during pregnancy and lactation. During pregnancy 96% and within the lactation period 84% of the women consumed at least 1 natural remedy. Phytotherapeutic drugs were used most frequently. In contrast to the widespread use of natural remedies by pregnant women and nursing mothers in this study, little information on the effectiveness and possible risks is available. Therefore it seems necessary to examine and evaluate natural remedies used during pregnancy and lactation.

  17. A niched Pareto tabu search for multi-objective optimal design of groundwater remediation systems

    NASA Astrophysics Data System (ADS)

    Yang, Yun; Wu, Jianfeng; Sun, Xiaomin; Wu, Jichun; Zheng, Chunmiao

    2013-05-01

    This study presents a new multi-objective optimization method, the niched Pareto tabu search (NPTS), for optimal design of groundwater remediation systems. The proposed NPTS is then coupled with the commonly used flow and transport code, MODFLOW and MT3DMS, to search for the near Pareto-optimal tradeoffs of groundwater remediation strategies. The difference between the proposed NPTS and the existing multiple objective tabu search (MOTS) lies in the use of the niche selection strategy and fitness archiving to maintain the diversity of the optimal solutions along the Pareto front and avoid repetitive calculations of the objective functions associated with the flow and transport model. Sensitivity analysis of the NPTS parameters is evaluated through a synthetic pump-and-treat remediation application involving two conflicting objectives, minimizations of both remediation cost and contaminant mass remaining in the aquifer. Moreover, the proposed NPTS is applied to a large-scale pump-and-treat groundwater remediation system of the field site at the Massachusetts Military Reservation (MMR) in Cape Cod, Massachusetts, involving minimizations of both total pumping rates and contaminant mass remaining in the aquifer. Additional comparison of the results based on the NPTS with those obtained from other two methods, namely the single objective tabu search (SOTS) and the nondominated sorting genetic algorithm II (NSGA-II), further indicates that the proposed NPTS has desirable computation efficiency, stability, and robustness and is a promising tool for optimizing the multi-objective design of groundwater remediation systems.

  18. In-situ groundwater remediation by selective colloid mobilization

    DOEpatents

    Seaman, John C.; Bertch, Paul M.

    1998-01-01

    An in-situ groundwater remediation pump and treat technique effective for reclamation of aquifers that have been contaminated with a mixed, metal-containing waste, which promotes selective mobilization of metal oxide colloids with a cationic surfactant, preferably a quaternary alkylammonium surfactant, without significantly reducing formation permeability that often accompanies large-scale colloid dispersion, thus increasing the efficiency of the remediation effort by enhancing the capture of strongly sorbing contaminants associated with the oxide phases. The resulting suspension can be separated from the bulk solution with controlled pH adjustments to destabilize the oxide colloids, and a clear supernatant which results that can be recycled through the injection well without further waste treatment.

  19. In-situ groundwater remediation by selective colloid mobilization

    DOEpatents

    Seaman, J.C.; Bertch, P.M.

    1998-12-08

    An in-situ groundwater remediation pump and treat technique is described which is effective for reclamation of aquifers that have been contaminated with a mixed, metal-containing waste, and which promotes selective mobilization of metal oxide colloids with a cationic surfactant, preferably a quaternary alkylammonium surfactant, without significantly reducing formation permeability that often accompanies large-scale colloid dispersion, thus increasing the efficiency of the remediation effort by enhancing the capture of strongly sorbing contaminants associated with the oxide phases. The resulting suspension can be separated from the bulk solution with controlled pH adjustments to destabilize the oxide colloids, and a clear supernatant which results that can be recycled through the injection well without further waste treatment. 3 figs.

  20. The antibacterial properties of an Aztec wound remedy.

    PubMed

    Davidson, J R; Ortiz de Montellano, B R

    1983-08-01

    Wound treatment practices of the Aztecs are discussed. The use of concentrated maguey sap (Agave ssp.) was widely dispersed and has persisted in folk medicine. A possible reason may be that it is effective. Laboratory analysis of maguey syrup indicates that its utilization as a remedy by ancient and modern Mesoamericans could contribute to the healing process of aerobic wound infections. Both pyogenic and enteric bacteria appear to be susceptible to maguey syrup. The traditional addition of salt to the remedy seems to enhance the effectiveness of the material in inhibiting the growth of one of the major causes of pus-forming or pyogenic infective processes, Staphylococcus aureus. This finding is additional proof of the effectiveness of pre-Hispanic medicine, and of the skills of pre-Hispanic physicians. PMID:6645570

  1. 40 CFR 300.435 - Remedial design/remedial action, operation and maintenance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS NATIONAL OIL AND HAZARDOUS SUBSTANCES POLLUTION CONTINGENCY PLAN Hazardous Substance Response § 300.435 Remedial design/remedial...

  2. 40 CFR 300.435 - Remedial design/remedial action, operation and maintenance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS NATIONAL OIL AND HAZARDOUS SUBSTANCES POLLUTION CONTINGENCY PLAN Hazardous Substance Response § 300.435 Remedial design/remedial...

  3. 40 CFR 300.435 - Remedial design/remedial action, operation and maintenance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS NATIONAL OIL AND HAZARDOUS SUBSTANCES POLLUTION CONTINGENCY PLAN Hazardous Substance Response § 300.435 Remedial design/remedial...

  4. ELECTROCHEMICAL REMEDIATION TECHNOLOGIES (ECRTS) - IN SITU REMEDIATION OF CONTAMINATED MARINE SEDIMENTS

    EPA Science Inventory

    This Innovative Technology Evaulation Report summarizes the results of the evaluation of the Electrochemical Remediation Technologies (ECRTs) process, developed by P2-Soil Remediation, Inc. (in partnership with Weiss Associates and Electro-Petroleum, Inc.). This evaluation was co...

  5. Air-Based Remediation Workshop - Section 7 Sustainable Remediation And Air-Based Technologies

    EPA Science Inventory

    Pursuant to the EPA-AIT Implementing Arrangement 7 for Technical Environmental Collaboration, Activity 11 "Remediation of Contaminated Sites, " the USEPA Office of International Affairs Organized a Forced Air Remediation Workshop in Taipei to deliver expert training to the Enviro...

  6. Air-Based Remediation Workshop - Section 8 Air-Based Remediation Technology Selection Logic

    EPA Science Inventory

    Pursuant to the EPA-AIT Implementing Arrangement 7 for Technical Environmental Collaboration, Activity 11 "Remediation of Contaminated Sites," the USEPA Office of International Affairs Organized a Forced Air Remediation Workshop in Taipei to deliver expert training to the Environ...

  7. 40 CFR 300.435 - Remedial design/remedial action, operation and maintenance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS NATIONAL OIL AND HAZARDOUS... remedial action objectives and remediation goals in the ROD, and is determined to be operational...

  8. Cognitive Remediation: A New Generation of Psychosocial Interventions for People with Schizophrenia

    PubMed Central

    Eack, Shaun M.

    2013-01-01

    Schizophrenia is a mental health condition characterized by broad impairments in cognition, which place profound limitations on functional recovery. Social work has an enduring legacy in pioneering the development of novel psychosocial interventions for people with schizophrenia, and this article introduces cognitive remediation, the latest advance in psychosocial treatments for the disorder designed to improve cognition. First, an overview of the nature of cognitive impairments and their functional consequences in schizophrenia is presented, followed by a description of the theoretical basis and key practice principles of cognitive remediation. Next, the latest biopsychosocial evidence for the efficacy of cognitive remediation in schizophrenia is critically reviewed. Finally, a model cognitive remediation program, Cognitive Enhancement Therapy, which was developed and evaluated by a social work-led multidisciplinary team is presented. Cognitive Enhancement Therapy represents a significant advance in cognitive remediation for schizophrenia, and uses a unique holistic approach that extends beyond traditional neurocognitive training to facilitate the achievement of adult social-cognitive milestones and broader functional recovery. It is concluded that cognitive remediation represents an effective next generation of psychosocial interventions that social workers can use to help improve the lives of many people who live with schizophrenia. PMID:23252315

  9. Use of surfactants for the remediation of contaminated soils: a review.

    PubMed

    Mao, Xuhui; Jiang, Rui; Xiao, Wei; Yu, Jiaguo

    2015-03-21

    Due to the great harm caused by soil contamination, there is an increasing interest to apply surfactants to the remediation of a variety of contaminated soils worldwide. This review article summarizes the findings of recent literatures regarding remediation of contaminated soils/sites using surfactants as an enhancing agent. For the surfactant-based remedial technologies, the adsorption behaviors of surfactants onto soil, the solubilizing capability of surfactants, and the toxicity and biocompatibility of surfactants are important considerations. Surfactants can enhance desorption of pollutants from soil, and promote bioremediation of organics by increasing bioavailability of pollutants. The removal of heavy metals and radionuclides from soils involves the mechanisms of dissolution, surfactant-associated complexation, and ionic exchange. In addition to the conventional ionic and nonionic surfactants, gemini surfactants and biosurfactants are also applied to soil remediation due to their benign features like lower critical micelle concentration (CMC) values and better biocompatibility. Mixed surfactant systems and combined use of surfactants with other additives are often adopted to improve the overall performance of soil washing solution for decontamination. Worldwide the field studies and full-scale remediation using surfactant-based technologies are yet limited, however, the already known cases reveal the good prospect of applying surfactant-based technologies to soil remediation.

  10. NEUROPSYCHOLOGICAL REMEDIATION OF HYPERACTIVE CHILDREN

    PubMed Central

    Agarwal, Neena; Rao, Shobini L.

    1997-01-01

    Hyperkinesis is associated with deficits of attention (poor allocation of attention resources, susceptibility to interference and perseveration); vigilance and perceptual sensitivity. Three boys aged 7-8 years with simple hyperkinesis were given cognitive tasks to improve the above functions in daily one hour sessions for a month. The children improved significantly in the above functions and behaviour. Three other children aged 5-8 years with simple hyperkinesis who were on medication improved only slightly in their behaviour during this period. Behavioural intervention and parental counselling were additional inputs to the children in both groups. Neuropsychological remediation combined with parental counselling and behavioural intervention shows promise in treating hyperactive children. PMID:21584098

  11. Night Blindness and Ancient Remedy

    PubMed Central

    Al Binali, H.A. Hajar

    2014-01-01

    The aim of this article is to briefly review the history of night blindness and its treatment from ancient times until the present. The old Egyptians, the Babylonians, the Greeks and the Arabs used animal liver for treatment and successfully cured the disease. The author had the opportunity to observe the application of the old remedy to a patient. Now we know what the ancients did not know, that night blindness is caused by Vitamin A deficiency and the animal liver is the store house for Vitamin A. PMID:25774260

  12. Electrokinetic remediation of oil-contaminated soils.

    PubMed

    Korolev, Vladimir A; Romanyukha, Olga V; Abyzova, Anna M

    2008-07-01

    This investigation was undertaken to determine the factors influencing electrokinetic remediation of soils from petroleum pollutants. The remediation method was applied in two versions: (i) static and (ii) flowing, when a sample was washed with leaching solution. It was found that all the soils studied can be purified using this technique. It was also observed that the mineral and grain-size composition of soils, their properties, and other parameters affect the remediation efficiency. The static and flowing versions of the remediation method removed 25-75% and 90-95% of the petroleum pollutants, respectively from the soils under study.

  13. Nuclear facility decommissioning and site remedial actions

    SciTech Connect

    Knox, N.P.; Webb, J.R.; Ferguson, S.D.; Goins, L.F.; Owen, P.T.

    1990-09-01

    The 394 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the eleventh in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Citations to foreign and domestic literature of all types -- technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions -- have been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy's Remedial Action Programs. Major sections are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Programs, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Grand Junction Remedial Action Program, (7) Uranium Mill Tailings Management, (8) Technical Measurements Center, (9) Remedial Action Program, and (10) Environmental Restoration Program. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and keywords. This report is a product of the Remedial Action Program Information Center (RAPIC), which selects and analyzes information on remedial actions and relevant radioactive waste management technologies.

  14. Tank waste remediation system (TWRS) mission analysis

    SciTech Connect

    Rieck, R.H.

    1996-10-03

    The Tank Waste Remediation System Mission Analysis provides program level requirements and identifies system boundaries and interfaces. Measures of success appropriate to program level accomplishments are also identified.

  15. Groundwater remediation at a wood preservatives site

    SciTech Connect

    Mital, H.K.; Damera, R.

    1994-12-31

    A wood treatment facility in Pennsylvania allegedly discharged about a million gallons of spent wood preservatives containing pentachlorophenol into a well from 1947 to 1963. Contaminated water was noticed in a creek adjacent to the site and was reported by the residents in 1972. Subsequently this site was placed on the National Priorities List (NPL) by the EPA in 1982. Tetra Tech, Inc. has performed Remedial Investigations (RI), Feasibility Studies (FS), Remedial Designs (RD) and Remedial Action (RA) at this Superfund site, for five years. This paper presents an overview of RI, FS, RD and treatability studies related to groundwater remediation.

  16. Phytochemical diversity drives plant–insect community diversity

    PubMed Central

    Richards, Lora A.; Dyer, Lee A.; Forister, Matthew L.; Smilanich, Angela M.; Dodson, Craig D.; Leonard, Michael D.; Jeffrey, Christopher S.

    2015-01-01

    What are the ecological causes and consequences of variation in phytochemical diversity within and between plant taxa? Despite decades of natural products discovery by organic chemists and research by chemical ecologists, our understanding of phytochemically mediated ecological processes in natural communities has been restricted to studies of either broad classes of compounds or a small number of well-characterized molecules. Until now, no studies have assessed the ecological causes or consequences of rigorously quantified phytochemical diversity across taxa in natural systems. Consequently, hypotheses that attempt to explain variation in phytochemical diversity among plants remain largely untested. We use spectral data from crude plant extracts to characterize phytochemical diversity in a suite of co-occurring plants in the tropical genus Piper (Piperaceae). In combination with 20 years of data focused on Piper-associated insects, we find that phytochemical diversity has a direct and positive effect on the diversity of herbivores but also reduces overall herbivore damage. Elevated chemical diversity is associated with more specialized assemblages of herbivores, and the cascading positive effect of phytochemistry on herbivore enemies is stronger as herbivore diet breadth narrows. These results are consistent with traditional hypotheses that predict positive associations between plant chemical diversity, insect herbivore diversity, and trophic specialization. It is clear from these results that high phytochemical diversity not only enhances the diversity of plant-associated insects but also contributes to the ecological predominance of specialized insect herbivores. PMID:26283384

  17. GROUND WATER REMEDIATION RESEARCH: PERMEABLE REACTIVE BARRIERS AND SOURCE ZONE REMEDIATION

    EPA Science Inventory

    An overview of ground water remediation research conducted at the Subsurface Protection and Remediation Division is provided. The focus of the overview is on Permeable Reactive Barriers for treatment of organic and inorganic contaminants and remediation of DNAPL source zones.

  18. Some Similarities and Differences Between Compositions Written by Remedial and Non-Remedial College Freshmen.

    ERIC Educational Resources Information Center

    House, Elizabeth B.; House, William J.

    The essays composed by 84 remedial and 77 nonremedial college freshmen were analyzed for some features proposed by Mina Shaughnessy as being characteristic of basic writers. The students were enrolled in either a beginning remedial class (098), a class at the next level of remediation (099), or a regular English class (101). The essays were…

  19. Risk-based economic decision analysis of remediation options at a PCE-contaminated site.

    PubMed

    Lemming, Gitte; Friis-Hansen, Peter; Bjerg, Poul L

    2010-05-01

    Remediation methods for contaminated sites cover a wide range of technical solutions with different remedial efficiencies and costs. Additionally, they may vary in their secondary impacts on the environment i.e. the potential impacts generated due to emissions and resource use caused by the remediation activities. More attention is increasingly being given to these secondary environmental impacts when evaluating remediation options. This paper presents a methodology for an integrated economic decision analysis which combines assessments of remediation costs, health risk costs and potential environmental costs. The health risks costs are associated with the residual contamination left at the site and its migration to groundwater used for drinking water. A probabilistic exposure model using first- and second-order reliability methods (FORM/SORM) is used to estimate the contaminant concentrations at a downstream groundwater well. Potential environmental impacts on the local, regional and global scales due to the site remediation activities are evaluated using life cycle assessments (LCA). The potential impacts on health and environment are converted to monetary units using a simplified cost model. A case study based upon the developed methodology is presented in which the following remediation scenarios are analyzed and compared: (a) no action, (b) excavation and off-site treatment of soil, (c) soil vapor extraction and (d) thermally enhanced soil vapor extraction by electrical heating of the soil. Ultimately, the developed methodology facilitates societal cost estimations of remediation scenarios which can be used for internal ranking of the analyzed options. Despite the inherent uncertainties of placing a value on health and environmental impacts, the presented methodology is believed to be valuable in supporting decisions on remedial interventions.

  20. [Basic principle and impact factors of soil vapor extraction (SVE) technology for remediation of contaminated soils by volatile and semivolatile organics].

    PubMed

    Liu, Shao-Qing; Jiang, Lin; Huang, Zhe; Li, Yan-Xia; Lin, Chun-Ye

    2011-03-01

    Because soil vapor extraction (SVE) is an effective, economic, and environmentally benign technology to remediate soils contaminated by volatile and semivolatile organics, it has been widely used in the remediation of these soils. The objectives of this paper were to introduce the basic principle of SVE and general steps of constructing SVE engineering, discuss major impact factors on remediation efficiency of SVE technology, and describe three kinds of enhanced SVE technologies. Finally, study and application progress of SVE technologies in China was introduced.

  1. Lasagna{trademark} soil remediation

    SciTech Connect

    1996-04-01

    Lasagna{trademark} is an integrated, in situ remediation technology being developed which remediates soils and soil pore water contaminated with soluble organic compounds. Lasagna{trademark} is especially suited to sites with low permeability soils where electroosmosis can move water faster and more uniformly than hydraulic methods, with very low power consumption. The process uses electrokinetics to move contaminants in soil pore water into treatment zones where the contaminants can be captured and decomposed. Initial focus is on trichloroethylene (TCE), a major contaminant at many DOE and industrial sites. Both vertical and horizontal configurations have been conceptualized, but fieldwork to date is more advanced for the vertical configuration. Major features of the technology are electrodes energized by direct current, which causes water and soluble contaminants to move into or through the treatment layers and also heats the soil; treatment zones containing reagents that decompose the soluble organic contaminants or adsorb contaminants for immobilization or subsequent removal and disposal; and a water management system that recycles the water that accumulates at the cathode (high pH) back to the anode (low pH) for acid-base neutralization. Alternatively, electrode polarity can be reversed periodically to reverse electroosmotic flow and neutralize pH.

  2. Characterization technologies for environmental remediation

    SciTech Connect

    Pruett, J.G.

    1991-01-01

    Improved site characterization technologies are being developed at Martin Marietta Energy Systems for the US Department of Energy (DOE) Office of Technology Development (OTD) in support of environmental restoration activities throughout the DOE complex. Since site characterization is an expensive and time consuming process that must be performed prior to, during, and following remediation efforts, an obvious way to reduce the overall cost of remediation is to develop improved characterization methods. For example, the Derivative Ultraviolet Absorption Spectrometer (DUVAS), which is being field tested as part of the OTD program, is a fiberoptic device for in situ, real time measurement of aromatic organic compounds in groundwater. A transportable, direct sampling Ion Trap Mass Spectrometer (ITMS) is being developed for continuous monitoring of hazardous organic compounds in air. In areas where the environment is hazardous to human health, it is desirous to perform site characterization remotely; if robotics are to be employed, the Ultrasonic Ranging and Data System (USRADS) can be used to provide telemetry information on robot location as well as sensor measurements. Once fully developed, these technologies can be transferred to the private sector. 19 refs., 2 tabs.

  3. Lasagna{trademark} soil remediation

    SciTech Connect

    1996-04-01

    Lasagna{trademark} is an integrated, in situ remediation technology being developed by an industrial consortium consisting of Monsanto, E. I. DuPont de Nemours & Co., Inc. (DuPont), and General Electric, with participation from the Department of Energy (DOE) Office of Environmental Management, Office of Science and Technology (EM-50), and the Environmental Protection Agency (EPA) Office of Research and Development (Figure 1). Lasagna{trademark} remediates soils and soil pore water contaminated with soluble organic compounds. Lasagna{trademark} is especially suited to sites with low permeability soils where electroosmosis can move water faster and more uniformly than hydraulic methods, with very low power consumption. The process uses electrokinetics to move contaminants in soil pore water into treatment zones where the contaminants can be captured or decomposed. Initial focus is on trichloroethylene (TCE), a major contaminant at many DOE and industrial sites. Both vertical and horizontal configurations have been conceptualized, but fieldwork to date is more advanced for the vertical configuration.

  4. Individualized remediation during fellowship training.

    PubMed

    Sparks, J William; Landrigan-Ossar, Mary; Vinson, Amy; Dearden, Jennifer; Navedo, Andres T; Waisel, David B; Holzman, Robert S

    2016-11-01

    The Accreditation Council for Graduate Medical Education requires medical training programs to monitor, track, and formally document a fellow's performance. If deficiencies are found, programs are expected to prepare and implement an effective plan of action for improvement and to ensure that graduates acquire the personal and professional attributes of an independent physician. We revised our evaluation policy and instituted a remediation protocol in 2008. Since that time, 130 pediatric anesthesia fellows have graduated. Seven fellows (5%) underwent departmental formal consultation for deficient behavior or poor performance. Of these 7 fellows, 4 underwent an individualized remediation program (IRP). A formal performance review and written contract, with specifically identified problems and general themes, recommendations for time-based successful behaviors, and clearly identified consequences for unsuccessful behaviors, was initiated for each fellow undergoing an IRP. All fellows who participated in this program completed their subspecialty training in pediatric anesthesia, and all eligible fellows have successfully achieved their subspecialty board certification. Our approach has the advantage of multimodality, time-based daily evaluations, and group discussions in the context of a Clinical Competency Committee. Utilization of an IRP as a metric for progress has features similar to effective cognitive behavioral therapy contracts and has ensured that our graduates are held to clearly delineated and specified skills and behaviors that allow them to work independently in the field of pediatric anesthesiology. PMID:27687433

  5. The Role of Motivation in Cognitive Remediation for People with Schizophrenia.

    PubMed

    Saperstein, Alice M; Medalia, Alice

    2016-01-01

    Motivation impairment is an often prominent component of schizophrenia symptomatology that impacts treatment engagement and reduces the functional benefit from psychosocial interventions. Intrinsic motivation in particular has been shown to be impaired in schizophrenia. Nowhere is the role of intrinsic motivation impairment more evident than in cognitive remediation for schizophrenia. This chapter describes the theoretical determinants of motivation to learn and illustrates how those determinants have been translated into therapeutic techniques that enhance intrinsic motivation in a clinical context. We review the extant research that indicates how motivation enhancing techniques yield treatment-related improvements within cognitive remediation therapy and, more broadly, in other behavioral skills-based interventions for schizophrenia.

  6. Theme: Supporting Professional Diversity.

    ERIC Educational Resources Information Center

    Moore, Eddie A.; And Others

    1994-01-01

    Includes "Supporting Diversity" (Moore); "Reflections on the Need for Diversity" (Bowen); "Understanding Impediments to Diversity in Agricultural Education" (Whent); "Mentoring Diverse Populations" (Jones); "Supporting Diversity: An Unfinished Agenda" (Moore); "Professorial Roles in Supporting Diversity in Teaching, Research, and University…

  7. 300-FF-1 remedial design report/remedial action work plan

    SciTech Connect

    Gustafson, F.W.

    1997-02-01

    The 300 Area has been divided into three operable units 300-FF-1, 300-FF-2, and 300-FF-5 all of which are in various stages of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) process. The 300-FF-1 Operable Unit, the subject of this report, includes liquid waste disposal sites, landfills, and a burial ground. This Remedial Design Report/Remedial Action Work Plan (RDR/RAWP) provides a summary description of each waste site included in the 300-FF-1 Operable Unit, the basis for remedial actions to be taken, and the remedial action approach and management process for implementing these actions. The remedial action approach and management sections provide a description of the remedial action process description, the project schedule, the project team, required planning documentation, the remedial action change process, the process for verifying attainment of the remedial action goals, and the required CERCLA and RCRA closeout documentation. Appendix A provides additional details on each waste site. In addition to remediation of the waste sites, waste generated during the remedial investigation/feasibility study portions of the project will also be disposed at the Environmental Restoration Disposal Facility (ERDF). Appendix B provides a summary of the modeling performed in the 300-FF-1 Phase 3 FS and a description of the modeling effort to be used to show attainment of the remedial action goals. Appendix C provides the sampling and analysis plan (SAP) for all sampling and field-screening activities performed during remediation and for verification of attainment with the remedial action goals. Appendix D provides the public involvement plan, prepared to ensure information is provided to the public during remedial design and remedial action processes.

  8. Enhancement of the microbial community biomass and diversity during air sparging bioremediation of a soil highly contaminated with kerosene and BTEX.

    PubMed

    Kabelitz, Nadja; Machackova, Jirina; Imfeld, Gwenaël; Brennerova, Maria; Pieper, Dietmar H; Heipieper, Hermann J; Junca, Howard

    2009-03-01

    In order to obtain insights in complexity shifts taking place in natural microbial communities under strong selective pressure, soils from a former air force base in the Czech Republic, highly contaminated with jet fuel and at different stages of a bioremediation air sparging treatment, were analyzed. By tracking phospholipid fatty acids and 16S rRNA genes, a detailed monitoring of the changes in quantities and composition of the microbial communities developed at different stages of the bioventing treatment progress was performed. Depending on the length of the air sparging treatment that led to a significant reduction in the contamination level, we observed a clear shift in the soil microbial community being dominated by Pseudomonads under the harsh conditions of high aromatic contamination to a status of low aromatic concentrations, increased biomass content, and a complex composition with diverse bacterial taxonomical branches.

  9. Autonomy and Motivation in Remedial Mathematics

    ERIC Educational Resources Information Center

    George, Michael

    2012-01-01

    Research has shown that a significant majority of students in remedial mathematics do not remediate successfully. Such widespread failure raises the question of motivation. Some would argue that the instructor should directly compel students to commit themselves to the course and its work. This can be done by mandating attendance and/or by…

  10. Mold Remediation in Schools and Commercial Buildings.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Radiation and Indoor Air.

    This document describes how to investigate and evaluate moisture and mold problems in educational facilities, and presents the key steps for implementing a remediation plan. A checklist is provided for conducting mold remediation efforts along with a resource list of helpful organizations and governmental agencies. Appendices contain a glossary,…

  11. Remedial Reading Students at Moraine Valley.

    ERIC Educational Resources Information Center

    Reis, Elizabeth

    In an effort to assess the effectiveness of their remedial reading courses, Moraine Valley Community College (MVCC) in Palos Hills, Illinois, undertook a study of the retention, course completion, and graduation rates of students who completed one of three remedial reading courses: RDG-040, basic skills for students reading below the 7th grade…

  12. 30 CFR 270.7 - Remedies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Remedies. 270.7 Section 270.7 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE NONDISCRIMINATION IN THE OUTER CONTINENTAL SHELF § 270.7 Remedies. In addition to the penalties available under 30 CFR...

  13. 30 CFR 270.7 - Remedies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Remedies. 270.7 Section 270.7 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE NONDISCRIMINATION IN THE OUTER CONTINENTAL SHELF § 270.7 Remedies. In addition to the penalties available under 30 CFR...

  14. Remedial Testing and Placement in Community Colleges

    ERIC Educational Resources Information Center

    Horn, Catherine; McCoy, Zoe; Campbell, Lea; Brock, Cheryl

    2009-01-01

    Almost half of students who enter college require some sort of remedial coursework. Further, states are increasingly moving the responsibility of postsecondary remediation away from four-year campuses to two-year institutions. Scholars and policymakers have grappled with best practice for successfully filling in academic gaps and moving students…

  15. Tank waste remediation system compensatory measure removal

    SciTech Connect

    MILLIKEN, N.J.

    1999-05-18

    In support of Fiscal Year 1998 Performance Agreement TWR1.4.3, ''Replace Compensatory Measures,'' the Tank Waste Remediation System is documenting the completion of field modifications supporting the removal of the temporary exemptions from the approved Tank Waste Remediation System Technical Safety Requirements (TSRs), HNF-SD-WM-TSR-006. These temporary exemptions or compensatory measures expire September 30, 1998.

  16. READING AND WRITING, THE REMEDIAL PROGRAM.

    ERIC Educational Resources Information Center

    Euclid English Demonstration Center, OH.

    THE PAPERS IN THIS COLLECTION EXPLAIN THE JUNIOR HIGH SCHOOL REMEDIAL PROGRAM IN READING AND WRITING DEVELOPED BY THE EUCLID ENGLISH DEMONSTRATION CENTER, THEY ARE (1) "REMEDIAL CLASSES AND THE TOTAL ENGLISH PROGRAM," BY GEORGE HILLOCKS, (2) "DEFINITION, ORIGIN, AND TREATMENT OF UNDERACHIEVEMENT," BY JANE W. KESSLER, (3) "READING SKILLS IN JUNIOR…

  17. Laboratory Experiment on Electrokinetic Remediation of Soil

    ERIC Educational Resources Information Center

    Elsayed-Ali, Alya H.; Abdel-Fattah, Tarek; Elsayed-Ali, Hani E.

    2011-01-01

    Electrokinetic remediation is a method of decontaminating soil containing heavy metals and polar organic contaminants by passing a direct current through the soil. An undergraduate chemistry laboratory is described to demonstrate electrokinetic remediation of soil contaminated with copper. A 30 cm electrokinetic cell with an applied voltage of 30…

  18. 30 CFR 570.7 - Remedies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Remedies. 570.7 Section 570.7 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE NONDISCRIMINATION IN THE OUTER CONTINENTAL SHELF § 570.7 Remedies. In addition to the penalties available under 30 CFR part 550, subpart...

  19. 30 CFR 570.7 - Remedies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Remedies. 570.7 Section 570.7 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE NONDISCRIMINATION IN THE OUTER CONTINENTAL SHELF § 570.7 Remedies. In addition to the penalties available under 30 CFR part 550, subpart...

  20. 30 CFR 570.7 - Remedies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Remedies. 570.7 Section 570.7 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE NONDISCRIMINATION IN THE OUTER CONTINENTAL SHELF § 570.7 Remedies. In addition to the penalties available under 30 CFR part 550, subpart...

  1. 18 CFR 706.103 - Remedial action.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Remedial action. 706.103 Section 706.103 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT General Provisions § 706.103 Remedial action. (a) A violation of this part by...

  2. 18 CFR 706.103 - Remedial action.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Remedial action. 706.103 Section 706.103 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT General Provisions § 706.103 Remedial action. (a) A violation of this part by...

  3. 48 CFR 203.906 - Remedies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Remedies. 203.906 Section 203.906 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF... for Contractor Employees 203.906 Remedies. (1) Not later than 30 days after receiving a DoD...

  4. 48 CFR 203.906 - Remedies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Remedies. 203.906 Section 203.906 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF... for Contractor Employees 203.906 Remedies. (1) Not later than 30 days after receiving a DoD...

  5. 32 CFR 536.36 - Related remedies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Related remedies. 536.36 Section 536.36 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY CLAIMS AND ACCOUNTS CLAIMS AGAINST THE UNITED STATES Investigation and Processing of Claims § 536.36 Related remedies. An ACO or a CPO...

  6. 18 CFR 706.103 - Remedial action.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Remedial action. 706.103 Section 706.103 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE... penalty prescribed by law; or (4) Disqualification for a particular assignment. (b) Remedial...

  7. 18 CFR 706.103 - Remedial action.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Remedial action. 706.103 Section 706.103 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE... penalty prescribed by law; or (4) Disqualification for a particular assignment. (b) Remedial...

  8. 18 CFR 706.103 - Remedial action.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Remedial action. 706.103 Section 706.103 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE... penalty prescribed by law; or (4) Disqualification for a particular assignment. (b) Remedial...

  9. 45 CFR 1177.3 - Other remedies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES CLAIMS COLLECTION § 1177.3 Other remedies. The remedies and sanctions available to the National Endowment for the Humanities under this part are not intended to be exclusive. The Chairperson of the National Endowment for the Humanities or his designee may impose...

  10. 45 CFR 1177.3 - Other remedies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES CLAIMS COLLECTION § 1177.3 Other remedies. The remedies and sanctions available to the National Endowment for the Humanities under this part are not intended to be exclusive. The Chairperson of the National Endowment for the Humanities or his designee may impose...

  11. Remedial Placements Found to Be Overused

    ERIC Educational Resources Information Center

    Sparks, Sarah D.

    2013-01-01

    At a time when more high schools are looking to their graduates' college-remediation rates as a clue to how well they prepare students for college and careers, new research findings suggest a significant portion of students who test into remedial classes don't actually need them. Separate studies from Teachers College, Columbia University, and the…

  12. 10 CFR 1008.15 - Civil remedies.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Civil remedies. 1008.15 Section 1008.15 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) RECORDS MAINTAINED ON INDIVIDUALS (PRIVACY ACT) Requests for Access or Amendment § 1008.15 Civil remedies. Subsection (g) of the Act provides that an individual may bring...

  13. 14 CFR 1212.800 - Civil remedies.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Civil remedies. 1212.800 Section 1212.800... Comply With Requirements of This Part § 1212.800 Civil remedies. Failure to comply with the requirements of the Privacy Act and this part could subject NASA to civil suit under the provisions of 5...

  14. 32 CFR 310.47 - Civil remedies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Civil remedies. 310.47 Section 310.47 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) PRIVACY PROGRAM DOD PRIVACY PROGRAM Privacy Act Violations § 310.47 Civil remedies. In addition to specific...

  15. Greener and sustainable remediation using iron nanomaterials

    EPA Science Inventory

    The main goal of remediation is to protect humans and the environment. Unfortunately, many remedial actions in the past concentrated more on site-specific environmental risks and conditions completely ignoring external social and economic impacts. Thus, new approach called green ...

  16. 45 CFR 1177.3 - Other remedies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES CLAIMS COLLECTION § 1177.3 Other remedies. The remedies and sanctions available to the National Endowment for the Humanities under this part are not intended to be exclusive. The Chairperson of the National Endowment for the Humanities or his designee may impose...

  17. 49 CFR 604.47 - Remedies.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of this part occurred, he or she may take one or more of the following actions: (1) Bar the recipient..., its employees, or its contractors. (b) In determining the type and amount of remedy, the Chief Counsel... office may mitigate the remedy when the recipient can document corrective action of alleged...

  18. Remedial Math: Its Effect on the Final Grade in Algebra.

    ERIC Educational Resources Information Center

    Head, L. Quinn; Lindsey, Jimmy D.

    1984-01-01

    The effectiveness of one remedial mathematics technique is examined. Results indicated that students who passed remedial math and then took college algebra had significantly higher final algebra grades than did undergraduates who failed remedial math. (MLW)

  19. Statewide Mandatory Remediation Policies: National, State, and Institutional Perspectives

    ERIC Educational Resources Information Center

    Peak, Charity S.

    2012-01-01

    Despite uncertainty related to student outcomes resulting from remediation (Bettinger & Long, 2009), eleven states mandate remedial education through common placement testing and standardized cutoff scores rather than permitting individual postsecondary institutions to establish remediation guidelines. Colorado, in particular, offers an…

  20. Mold remediation in a hospital.

    PubMed

    Lee, Tang G

    2009-01-01

    As occupants in a hospital, patients are susceptible to air contaminants that can include biological agents dispersed throughout the premise. An exposed patient can become ill and require medical intervention. A consideration for patients is that they may have become environmentally sensitive and require placement in an environment that does not compromise their health. Unfortunately, the hospital environment often contains more biological substances than can be expected in an office or home environment. When a hospital also experiences water intrusion such as flooding or water leaks, resulting mold growth can seriously compromise the health of patients and others such as nursing staff and physicians (Burge, Indoor Air and Infectious Disease. Occupational Medicine: State of the Art Reviews, 1980; Lutz et al., Clinical Infectious Diseases 37: 786-793, 2003). Micro-organism growth can propagate if the water is not addressed quickly and effectively. Immunocompromised patients are particularly at risk when subjected to fungal infection such that the US Center for Disease Control issued guideline for building mold in health care facilities (Centers for Disease and Control [CDC], Centers for Disease and Control: Questions and Answers on Stachybotrys chartarum and Other Molds, 2000). This paper is based on mold remediation of one portion of a hospital unit due to water from construction activity and inadequate maintenance, resulting in mold growth. A large proportion of the hospital staff, primarily nurses in the dialysis unit, exhibited health symptoms consistent with mold exposure. Unfortunately, the hospital administrators did not consider the mold risk to be serious and refused an independent consultant retained by the nurse's union to examine the premise (Canadian Broadcasting Corporation [CBC], Nurses file complaints over mold at Foothills. Canadian Broadcasting Corporation, 2003). The nurse's union managed to have the premise examined by submitting a court order of