Sample records for coupled environmental processes

  1. SeSBench - An initiative to benchmark reactive transport models for environmental subsurface processes

    NASA Astrophysics Data System (ADS)

    Jacques, Diederik

    2017-04-01

    As soil functions are governed by a multitude of interacting hydrological, geochemical and biological processes, simulation tools coupling mathematical models for interacting processes are needed. Coupled reactive transport models are a typical example of such coupled tools mainly focusing on hydrological and geochemical coupling (see e.g. Steefel et al., 2015). Mathematical and numerical complexity for both the tool itself or of the specific conceptual model can increase rapidly. Therefore, numerical verification of such type of models is a prerequisite for guaranteeing reliability and confidence and qualifying simulation tools and approaches for any further model application. In 2011, a first SeSBench -Subsurface Environmental Simulation Benchmarking- workshop was held in Berkeley (USA) followed by four other ones. The objective is to benchmark subsurface environmental simulation models and methods with a current focus on reactive transport processes. The final outcome was a special issue in Computational Geosciences (2015, issue 3 - Reactive transport benchmarks for subsurface environmental simulation) with a collection of 11 benchmarks. Benchmarks, proposed by the participants of the workshops, should be relevant for environmental or geo-engineering applications; the latter were mostly related to radioactive waste disposal issues - excluding benchmarks defined for pure mathematical reasons. Another important feature is the tiered approach within a benchmark with the definition of a single principle problem and different sub problems. The latter typically benchmarked individual or simplified processes (e.g. inert solute transport, simplified geochemical conceptual model) or geometries (e.g. batch or one-dimensional, homogeneous). Finally, three codes should be involved into a benchmark. The SeSBench initiative contributes to confidence building for applying reactive transport codes. Furthermore, it illustrates the use of those type of models for different environmental and geo-engineering applications. SeSBench will organize new workshops to add new benchmarks in a new special issue. Steefel, C. I., et al. (2015). "Reactive transport codes for subsurface environmental simulation." Computational Geosciences 19: 445-478.

  2. Individual traits and environmental factors influencing sleep timing: a study of 225 Japanese couples.

    PubMed

    Hida, Akiko; Kitamura, Shingo; Enomoto, Minori; Nozaki, Kentaro; Moriguchi, Yoshiya; Echizenya, Masaru; Kusanagi, Hiroaki; Mishima, Kazuo

    2012-03-01

    Behavioral and physiological processes, such as sleep-wakefulness, thermoregulation, and hormone secretion, exhibit 24-h rhythms in most organisms. These biological rhythms are driven by the circadian clock system and are entrained by the external environment, which in the case of humans includes social time schedules. Couples might be ideal experimental subjects to discriminate between individual traits and environmental factors, as they share lifestyle habits but not genetic backgrounds. In this study, sleep timing was compared between married Japanese couples (n = 225) who had lived together for 1 yr or more (mean 17 yrs). Additionally, the authors evaluated the influence of individual traits and environmental factors on an individual's sleep timing per each couple. The results reveal that the sleep timings of a couple are mainly associated with the chronotypes of the husband and wife, whereas the sleep timings are significantly influenced by certain environmental factors. The findings suggest that chronotype remains one of the major determinants of an individual's sleep onset and wake times. Understanding an individual's chronotype may help improve the quality of life issues surrounding sleep.

  3. Coupling of ultrasound-assisted extraction and expanded bed adsorption for simplified medicinal plant processing and its theoretical model: extraction and enrichment of ginsenosides from Radix Ginseng as a case study.

    PubMed

    Mi, Jianing; Zhang, Min; Zhang, Hongyang; Wang, Yuerong; Wu, Shikun; Hu, Ping

    2013-02-01

    A high-efficient and environmental-friendly method for the preparation of ginsenosides from Radix Ginseng using the method of coupling of ultrasound-assisted extraction with expanded bed adsorption is described. Based on the optimal extraction conditions screened by surface response methodology, ginsenosides were extracted and adsorbed, then eluted by the two-step elution protocol. The comparison results between the coupling of ultrasound-assisted extraction with expanded bed adsorption method and conventional method showed that the former was better than the latter in both process efficiency and greenness. The process efficiency and energy efficiency of the coupling of ultrasound-assisted extraction with expanded bed adsorption method rapidly increased by 1.4-fold and 18.5-fold of the conventional method, while the environmental cost and CO(2) emission of the conventional method were 12.9-fold and 17.0-fold of the new method. Furthermore, the theoretical model for the extraction of targets was derived. The results revealed that the theoretical model suitably described the process of preparing ginsenosides by the coupling of ultrasound-assisted extraction with expanded bed adsorption system. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Development of Chemical Process Design and Control for Sustainability

    EPA Science Inventory

    This contribution describes a novel process systems engineering framework that couples advanced control with sustainability evaluation and decision making for the optimization of process operations to minimize environmental impacts associated with products, materials, and energy....

  5. Environmental assessment of different advanced oxidation processes applied to a bleaching Kraft mill effluent.

    PubMed

    Muñoz, Iván; Rieradevall, Joan; Torrades, Francesc; Peral, José; Domènech, Xavier

    2006-01-01

    Different advanced oxidation processes (AOPs) have been applied to remove the organic carbon content of a paper mill effluent originating from the Kraft pulp bleaching process. The considered AOPs were: TiO(2)-mediated heterogeneous photocatalysis, TiO(2)-mediated heterogeneous photocatalysis assisted with H(2)O(2), TiO(2)-mediated heterogeneous photocatalysis coupled with Fenton, photo-Fenton, ozonation and ozonation with UV-A light irradiation. The application of the selected AOPs all resulted in a considerable decrease in dissolved organic carbon (DOC) content with variable treatment efficiencies depending upon the nature/type of the applied AOP. A Life Cycle Assessment (LCA) study was used as a tool to compare the different AOPs in terms of their environmental impact. Heterogeneous photocatalysis coupled with the Fenton's reagent proved to have the lowest environmental impact accompanied with a moderate-to-high DOC removal rate. On the other hand, heterogeneous photocatalysis appeared to be the worst AOP both in terms of DOC abatement rate and environmental impact. For the studied AOPs, LCA has indicated that the environmental impact was attributable to the high electrical energy (power) consumption necessary to run a UV-A lamp or to produce ozone.

  6. POLLUTION PREVENTION IN THE EARLY STAGES OF HIERARCHICAL PROCESS DESIGN

    EPA Science Inventory

    Hierarchical methods are often used in the conceptual stages of process design to synthesize and evaluate process alternatives. In this work, the methods of hierarchical process design will be focused on environmental aspects. In particular, the design methods will be coupled to ...

  7. Lattice Boltzmann-Based Approaches for Pore-Scale Reactive Transport

    DOE PAGES

    Yoon, Hongkyu; Kang, Qinjun; Valocchi, Albert J.

    2015-07-29

    Here an important geoscience and environmental applications such as geologic carbon storage, environmental remediation, and unconventional oil and gas recovery are best understood in the context of reactive flow and multicomponent transport in the subsurface environment. The coupling of chemical and microbiological reactions with hydrological and mechanical processes can lead to complex behaviors across an enormous range of spatial and temporal scales. These coupled responses are also strongly influenced by the heterogeneity and anisotropy of the geologic formations. Reactive transport processes can change the pore morphology at the pore scale, thereby leading to nonlinear interactions with advective and diffusive transport,more » which can strongly influence larger-scale properties such as permeability and dispersion.« less

  8. The UKC2 regional coupled environmental prediction system

    NASA Astrophysics Data System (ADS)

    Lewis, Huw W.; Castillo Sanchez, Juan Manuel; Graham, Jennifer; Saulter, Andrew; Bornemann, Jorge; Arnold, Alex; Fallmann, Joachim; Harris, Chris; Pearson, David; Ramsdale, Steven; Martínez-de la Torre, Alberto; Bricheno, Lucy; Blyth, Eleanor; Bell, Victoria A.; Davies, Helen; Marthews, Toby R.; O'Neill, Clare; Rumbold, Heather; O'Dea, Enda; Brereton, Ashley; Guihou, Karen; Hines, Adrian; Butenschon, Momme; Dadson, Simon J.; Palmer, Tamzin; Holt, Jason; Reynard, Nick; Best, Martin; Edwards, John; Siddorn, John

    2018-01-01

    It is hypothesized that more accurate prediction and warning of natural hazards, such as of the impacts of severe weather mediated through various components of the environment, require a more integrated Earth System approach to forecasting. This hypothesis can be explored using regional coupled prediction systems, in which the known interactions and feedbacks between different physical and biogeochemical components of the environment across sky, sea and land can be simulated. Such systems are becoming increasingly common research tools. This paper describes the development of the UKC2 regional coupled research system, which has been delivered under the UK Environmental Prediction Prototype project. This provides the first implementation of an atmosphere-land-ocean-wave modelling system focussed on the United Kingdom and surrounding seas at km-scale resolution. The UKC2 coupled system incorporates models of the atmosphere (Met Office Unified Model), land surface with river routing (JULES), shelf-sea ocean (NEMO) and ocean waves (WAVEWATCH III). These components are coupled, via OASIS3-MCT libraries, at unprecedentedly high resolution across the UK within a north-western European regional domain. A research framework has been established to explore the representation of feedback processes in coupled and uncoupled modes, providing a new research tool for UK environmental science. This paper documents the technical design and implementation of UKC2, along with the associated evaluation framework. An analysis of new results comparing the output of the coupled UKC2 system with relevant forced control simulations for six contrasting case studies of 5-day duration is presented. Results demonstrate that performance can be achieved with the UKC2 system that is at least comparable to its component control simulations. For some cases, improvements in air temperature, sea surface temperature, wind speed, significant wave height and mean wave period highlight the potential benefits of coupling between environmental model components. Results also illustrate that the coupling itself is not sufficient to address all known model issues. Priorities for future development of the UK Environmental Prediction framework and component systems are discussed.

  9. Neural Cross-Frequency Coupling: Connecting Architectures, Mechanisms, and Functions.

    PubMed

    Hyafil, Alexandre; Giraud, Anne-Lise; Fontolan, Lorenzo; Gutkin, Boris

    2015-11-01

    Neural oscillations are ubiquitously observed in the mammalian brain, but it has proven difficult to tie oscillatory patterns to specific cognitive operations. Notably, the coupling between neural oscillations at different timescales has recently received much attention, both from experimentalists and theoreticians. We review the mechanisms underlying various forms of this cross-frequency coupling. We show that different types of neural oscillators and cross-frequency interactions yield distinct signatures in neural dynamics. Finally, we associate these mechanisms with several putative functions of cross-frequency coupling, including neural representations of multiple environmental items, communication over distant areas, internal clocking of neural processes, and modulation of neural processing based on temporal predictions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Studying the Impacts of Environmental Factors and Agricultural Management on Methane Emissions from Rice Paddies Using a Land Surface Model

    NASA Astrophysics Data System (ADS)

    Lin, T. S.; Gahlot, S.; Shu, S.; Jain, A. K.; Kheshgi, H. S.

    2017-12-01

    Continued growth in population is projected to drive increased future demand for rice and the methane emissions associated with its production. However, observational studies of methane emissions from rice have reported seemingly conflicting results and do not all support this projection. In this study we couple an ecophysiological process-based rice paddy module and a methane emission module with a land surface model, Integrated Science Assessment Model (ISAM), to study the impacts of various environmental factors and agricultural management practices on rice production and methane emissions from rice fields. This coupled modeling framework accounts for dynamic rice growth processes with adaptation of photosynthesis, rice-specific phenology, biomass accumulation, leaf area development and structures responses to water, temperature, light and nutrient stresses. The coupled model is calibrated and validated with observations from various rice cultivation fields. We find that the differing results of observational studies can be caused by the interactions of environmental factors, including climate, atmospheric CO2 concentration, and N deposition, and agricultural management practices, such as irrigation and N fertilizer applications, with rice production at spatial and temporal scales.

  11. Adding Processing Functionality to the Sensor Web

    NASA Astrophysics Data System (ADS)

    Stasch, Christoph; Pross, Benjamin; Jirka, Simon; Gräler, Benedikt

    2017-04-01

    The Sensor Web allows discovering, accessing and tasking different kinds of environmental sensors in the Web, ranging from simple in-situ sensors to remote sensing systems. However, (geo-)processing functionality needs to be applied to integrate data from different sensor sources and to generate higher level information products. Yet, a common standardized approach for processing sensor data in the Sensor Web is still missing and the integration differs from application to application. Standardizing not only the provision of sensor data, but also the processing facilitates sharing and re-use of processing modules, enables reproducibility of processing results, and provides a common way to integrate external scalable processing facilities or legacy software. In this presentation, we provide an overview on on-going research projects that develop concepts for coupling standardized geoprocessing technologies with Sensor Web technologies. At first, different architectures for coupling sensor data services with geoprocessing services are presented. Afterwards, profiles for linear regression and spatio-temporal interpolation of the OGC Web Processing Services that allow consuming sensor data coming from and uploading predictions to Sensor Observation Services are introduced. The profiles are implemented in processing services for the hydrological domain. Finally, we illustrate how the R software can be coupled with existing OGC Sensor Web and Geoprocessing Services and present an example, how a Web app can be built that allows exploring the results of environmental models in an interactive way using the R Shiny framework. All of the software presented is available as Open Source Software.

  12. Tinamit: Making coupled system dynamics models accessible to stakeholders

    NASA Astrophysics Data System (ADS)

    Malard, Julien; Inam Baig, Azhar; Rojas Díaz, Marcela; Hassanzadeh, Elmira; Adamowski, Jan; Tuy, Héctor; Melgar-Quiñonez, Hugo

    2017-04-01

    Model coupling is increasingly used as a method of combining the best of two models when representing socio-environmental systems, though barriers to successful model adoption by stakeholders are particularly present with the use of coupled models, due to their high complexity and typically low implementation flexibility. Coupled system dynamics - physically-based modelling is a promising method to improve stakeholder participation in environmental modelling while retaining a high level of complexity for physical process representation, as the system dynamics components are readily understandable and can be built by stakeholders themselves. However, this method is not without limitations in practice, including 1) inflexible and complicated coupling methods, 2) difficult model maintenance after the end of the project, and 3) a wide variety of end-user cultures and languages. We have developed the open-source Python-language software tool Tinamit to overcome some of these limitations to the adoption of stakeholder-based coupled system dynamics - physically-based modelling. The software is unique in 1) its inclusion of both a graphical user interface (GUI) and a library of available commands (API) that allow users with little or no coding abilities to rapidly, effectively, and flexibly couple models, 2) its multilingual support for the GUI, allowing users to couple models in their preferred language (and to add new languages as necessary for their community work), and 3) its modular structure allowing for very easy model coupling and modification without the direct use of code, and to which programming-savvy users can easily add support for new types of physically-based models. We discuss how the use of Tinamit for model coupling can greatly increase the accessibility of coupled models to stakeholders, using an example of a stakeholder-built system dynamics model of soil salinity issues in Pakistan coupled with the physically-based soil salinity and water flow model SAHYSMOD. Different socioeconomic and environmental policies for soil salinity remediation are tested within the coupled model, allowing for the identification of the most efficient actions from an environmental and a farmer economy standpoint while taking into account the complex feedbacks between socioeconomics and the physical environment.

  13. Cavity-Mediated Coherent Coupling between Distant Quantum Dots

    NASA Astrophysics Data System (ADS)

    Nicolí, Giorgio; Ferguson, Michael Sven; Rössler, Clemens; Wolfertz, Alexander; Blatter, Gianni; Ihn, Thomas; Ensslin, Klaus; Reichl, Christian; Wegscheider, Werner; Zilberberg, Oded

    2018-06-01

    Scalable architectures for quantum information technologies require one to selectively couple long-distance qubits while suppressing environmental noise and cross talk. In semiconductor materials, the coherent coupling of a single spin on a quantum dot to a cavity hosting fermionic modes offers a new solution to this technological challenge. Here, we demonstrate coherent coupling between two spatially separated quantum dots using an electronic cavity design that takes advantage of whispering-gallery modes in a two-dimensional electron gas. The cavity-mediated, long-distance coupling effectively minimizes undesirable direct cross talk between the dots and defines a scalable architecture for all-electronic semiconductor-based quantum information processing.

  14. A Coupled Simulation Architecture for Agent-Based/Geohydrological Modelling

    NASA Astrophysics Data System (ADS)

    Jaxa-Rozen, M.

    2016-12-01

    The quantitative modelling of social-ecological systems can provide useful insights into the interplay between social and environmental processes, and their impact on emergent system dynamics. However, such models should acknowledge the complexity and uncertainty of both of the underlying subsystems. For instance, the agent-based models which are increasingly popular for groundwater management studies can be made more useful by directly accounting for the hydrological processes which drive environmental outcomes. Conversely, conventional environmental models can benefit from an agent-based depiction of the feedbacks and heuristics which influence the decisions of groundwater users. From this perspective, this work describes a Python-based software architecture which couples the popular NetLogo agent-based platform with the MODFLOW/SEAWAT geohydrological modelling environment. This approach enables users to implement agent-based models in NetLogo's user-friendly platform, while benefiting from the full capabilities of MODFLOW/SEAWAT packages or reusing existing geohydrological models. The software architecture is based on the pyNetLogo connector, which provides an interface between the NetLogo agent-based modelling software and the Python programming language. This functionality is then extended and combined with Python's object-oriented features, to design a simulation architecture which couples NetLogo with MODFLOW/SEAWAT through the FloPy library (Bakker et al., 2016). The Python programming language also provides access to a range of external packages which can be used for testing and analysing the coupled models, which is illustrated for an application of Aquifer Thermal Energy Storage (ATES).

  15. Institutionalizing policy-level health impact assessment in Europe: is coupling health impact assessment with strategic environmental assessment the next step forward?

    PubMed Central

    Wright, John; Parry, Jayne; Scully, Edward

    2005-01-01

    European Union (EU) Member States are interested in using health impact assessment (HIA) as a means of safeguarding their obligations to protect human health under the 1997 Treaty of Amsterdam. However, several have encountered difficulties institutionalizing HIA with the policy-making process. As a consequence, the World Health Organization (WHO) Regional Office for Europe has suggested coupling HIA with strategic environmental assessment (SEA). Traditionally, the incorporation of HIA into other forms of impact assessment has been resisted, for fear of losing its focus on health issues to environmental concerns, and compromising its social model of health with the introduction of biophysical indicators. But can these fears be substantiated? In this paper, we investigate the grounds for such concerns by reviewing the relevant policy documents and departmental guidelines of four non-European countries that have considered the use of integrated assessment. We found that the case for associating HIA with SEA in Europe is strong, and offers potential solutions to problems of screening, theoretical framework, causal pathways and ready entry to the policy process. Coupling HIA with SEA may thus be the next step forward in a longer journey towards institutionalizing HIA as an independent policy-linked device. PMID:15976899

  16. Institutionalizing policy-level health impact assessment in Europe: is coupling health impact assessment with strategic environmental assessment the next step forward?

    PubMed

    Wright, John; Parry, Jayne; Scully, Edward

    2005-06-01

    European Union (EU) Member States are interested in using health impact assessment (HIA) as a means of safeguarding their obligations to protect human health under the 1997 Treaty of Amsterdam. However, several have encountered difficulties institutionalizing HIA with the policy-making process. As a consequence, the World Health Organization (WHO) Regional Office for Europe has suggested coupling HIA with strategic environmental assessment (SEA). Traditionally, the incorporation of HIA into other forms of impact assessment has been resisted, for fear of losing its focus on health issues to environmental concerns, and compromising its social model of health with the introduction of biophysical indicators. But can these fears be substantiated? In this paper, we investigate the grounds for such concerns by reviewing the relevant policy documents and departmental guidelines of four non-European countries that have considered the use of integrated assessment. We found that the case for associating HIA with SEA in Europe is strong, and offers potential solutions to problems of screening, theoretical framework, causal pathways and ready entry to the policy process. Coupling HIA with SEA may thus be the next step forward in a longer journey towards institutionalizing HIA as an independent policy-linked device.

  17. Challenges in coupling LTER with environmental assessments: An insight from potential and reality of the Chinese Ecological Research Network in servicing environment assessments.

    PubMed

    Xia, Shaoxia; Liu, Yu; Yu, Xiubo; Fu, Bojie

    2018-08-15

    Environmental assessments estimate, evaluate and predict the consequences of natural processes and human activities on the environment. Long-term ecosystem observation and research networks (LTERs) are potentially valuable infrastructure to support environmental assessments. However, very few environmental assessments have successfully incorporated them. In this study, we try to reveal the current status of coupling LTERs with environmental assessments and look at the challenges involved in improving this coupling through exploring the role that Chinese Ecological Research Network (CERN), the LTER of China, currently plays in regional environment assessments. A review of official protocols and standards, regional assessments and CERN researches related to ecosystems and environment shows that there is great potential for coupling CERN with environment assessments. However in practice, CERN does not currently play the expected role. Remote sensing and irregular inventory data are still the main data sources currently used in regional assessments. Several causes led to the present situation: (1) insufficient cross-site research and failure to scale up site-level variables to the regional scale; (2) data barriers resulting from incompatible protocols and low data usability due to lack of data assimilation and scaling; and (3) absence of indicators relevant to human activities in existing monitoring protocols. For these reasons, enhancing cross-site monitoring and research, data assimilation and scaling up are critical steps required to improve coupling of LTER with environmental assessments. Site-focused long-term monitoring should be combined with wide-scale ground surveys and remote sensing to establish an effective connection between different environmental monitoring platforms for regional assessments. It is also necessary to revise the current monitoring protocols to include human activities and their impacts on the ecosystem, or change the LTERs into Long-Term Socio-Ecological Research (LTSER) networks. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. The Effects of Dynamical Rates on Species Coexistence in a Variable Environment: The Paradox of the Plankton Revisited.

    PubMed

    Li, Lina; Chesson, Peter

    2016-08-01

    Hutchinson's famous hypothesis for the "paradox of the plankton" has been widely accepted, but critical aspects have remained unchallenged. Hutchinson argued that environmental fluctuations would promote coexistence when the timescale for environmental change is comparable to the timescale for competitive exclusion. Using a consumer-resource model, we do find that timescales of processes are important. However, it is not the time to exclusion that must be compared with the time for environmental change but the time for resource depletion. Fast resource depletion, when resource consumption is favored for different species at different times, strongly promotes coexistence. The time for exclusion is independent of the rate of resource depletion. Therefore, the widely believed predictions of Hutchinson are misleading. Fast resource depletion, as determined by environmental conditions, ensures strong coupling of environmental processes and competition, which leads to enhancement over time of intraspecific competition relative to interspecific competition as environmental shifts favor different species at different times. This critical coupling is measured by the covariance between environment and competition. Changes in this quantity as densities change determine the stability of coexistence and provide the key to rigorous analysis, both theoretically and empirically, of coexistence in a variable environment. These ideas apply broadly to diversity maintenance in variable environments whether the issue is species diversity or genetic diversity and competition or apparent competition.

  19. Blinded by the light? Nearshore energy pathway coupling and relative predator biomass increase with reduced water transparency across lakes.

    PubMed

    Tunney, Tyler D; McCann, Kevin S; Jarvis, Lauren; Lester, Nigel P; Shuter, Brian J

    2018-04-01

    Habitat coupling is a concept that refers to consumer integration of resources derived from different habitats. This coupling unites fundamental food web pathways (e.g., cross-habitat trophic linkages) that mediate key ecological processes such as biomass flows, nutrient cycling, and stability. We consider the influence of water transparency, an important environmental driver in aquatic ecosystems, on habitat coupling by a light-sensitive predator, walleye (Sander vitreus), and its prey in 33 Canadian lakes. Our large-scale, across-lake study shows that the contribution of nearshore carbon (δ 13 C) relative to offshore carbon (δ 13 C) to walleye is higher in less transparent lakes. To a lesser degree, the contribution of nearshore carbon increased with a greater proportion of prey in nearshore compared to offshore habitats. Interestingly, water transparency and habitat coupling predict among-lake variation in walleye relative biomass. These findings support the idea that predator responses to changing conditions (e.g., water transparency) can fundamentally alter carbon pathways, and predator biomass, in aquatic ecosystems. Identifying environmental factors that influence habitat coupling is an important step toward understanding spatial food web structure in a changing world.

  20. Clustering and phase synchronization in populations of coupled phase oscillators

    NASA Astrophysics Data System (ADS)

    Cascallares, Guadalupe; Gleiser, Pablo M.

    2015-10-01

    In many species daily rhythms are endogenously generated by groups of coupled neurons that play the role of a circadian pacemaker. The adaptation of the circadian clock to environmental and seasonal changes has been proposed to be regulated by a dual oscillator system. In order to gain insight into this model, we analyzed the synchronization properties of two fully coupled groups of Kuramoto oscillators. Each group has an internal coupling parameter and the interaction between the two groups can be controlled by two parameters allowing for symmetric or non-symmetric coupling. We show that even for such a simple model counterintuitive behaviours take place, such as a global decrease in synchrony when the coupling between the groups is increased. Through a detailed analysis of the local synchronization processes we explain this behaviour.

  1. Environmental Coupling Modulates the Attractors of Rhythmic Coordination

    ERIC Educational Resources Information Center

    Kudo, Kazutoshi; Park, Hyeonsaeng; Kay, Bruce A.; Turvey, M. T.

    2006-01-01

    A simple instance of coupling behavior to the environment is oscillating the hands in pace with metronome beats. This environmental coupling can be weaker (1 beat per cycle) or stronger (2 beats per cycle). The authors examined whether strength of environmental coupling enhanced the stability of in-phase bimanual coordination. Detuning by…

  2. Systemic-constructivist couple therapy (SCCT): Description of approach, theoretical advances, and published longitudinal evidence.

    PubMed

    Reid, David W; Doell, Faye K; Dalton, E Jane; Ahmad, Saunia

    2008-12-01

    The systemic-constructivist approach to studying and benefiting couples was derived from qualitative and quantitative research on distressed couples over the past 10 years. Systemic-constructivist couple therapy (SCCT) is the clinical intervention that accompanies the approach. SCCT guides the therapist to work with both the intrapersonal and the interpersonal aspects of marriage while also integrating the social-environmental context of the couple. The theory that underlies SCCT is explained, including concepts such as we-ness and interpersonal processing. The primary components of the therapy are described. Findings described previously in an inaugural monograph containing extensive research demonstrating the long-term utility of SCCT are reviewed. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  3. Journey on greener pathways: from the use of alternate energy inputs and benign reaction media to sustainable applications of nano-catalysts in synthesis and environmental remediation

    EPA Science Inventory

    Sustainable synthetic processes developed during the past two decades involving the use of alternate energy inputs and greener reaction media are summarized. These processes include examples of coupling reactions, the synthesis of heterocyclic compounds, and a variety of reactio...

  4. UK Environmental Prediction - integration and evaluation at the convective scale

    NASA Astrophysics Data System (ADS)

    Fallmann, Joachim; Lewis, Huw; Castillo, Juan Manuel; Pearson, David; Harris, Chris; Saulter, Andy; Bricheno, Lucy; Blyth, Eleanor

    2016-04-01

    It has long been understood that accurate prediction and warning of the impacts of severe weather requires an integrated approach to forecasting. For example, high impact weather is typically manifested through various interactions and feedbacks between different components of the Earth System. Damaging high winds can lead to significant damage from the large waves and storm surge along coastlines. The impact of intense rainfall can be translated through saturated soils and land surface processes, high river flows and flooding inland. The substantial impacts on individuals, businesses and infrastructure of such events indicate a pressing need to understand better the value that might be delivered through more integrated environmental prediction. To address this need, the Met Office, NERC Centre for Ecology & Hydrology and NERC National Oceanography Centre have begun to develop the foundations of a coupled high resolution probabilistic forecast system for the UK at km-scale. This links together existing model components of the atmosphere, coastal ocean, land surface and hydrology. Our initial focus has been on a 2-year Prototype project to demonstrate the UK coupled prediction concept in research mode. This presentation will provide an update on UK environmental prediction activities. We will present the results from the initial implementation of an atmosphere-land-ocean coupled system and discuss progress and initial results from further development to integrate wave interactions. We will discuss future directions and opportunities for collaboration in environmental prediction, and the challenges to realise the potential of integrated regional coupled forecasting for improving predictions and applications.

  5. Which benefits in the use of a modeling platform : The VSoil example.

    NASA Astrophysics Data System (ADS)

    Lafolie, François; Cousin, Isabelle; Mollier, Alain; Pot, Valérie; Maron, Pierre-Alain; Moitrier, Nicolas; Nouguier, Cedric; Moitrier, Nathalie; Beudez, Nicolas

    2015-04-01

    In the environmental community the need for coupling the models and the associated knowledges emerged recently. The development of a coupling tool or of a modeling platform is mainly driven by the necessity to create models accounting for multiple processes and to take into account the feed back between these processes. Models focusing on a restricted number of processes exist and thus the coupling of these numerical tools appeared as an efficient and rapid mean to fill up the identified gaps. Several tools have been proposed : OMS3 (David et al. 2013) ; CSDMS framework (Peckham et al. 2013) ; the Open MI project developed within the frame of European Community (Open MI, 2011). However, what we should expect from a modeling platform could be more ambitious than only coupling existing numerical codes. We believe that we need to share easily not only our numerical representations but also the attached knowledges. We need to rapidly and easily develop complex models to have tools to bring responses to current issues on soil functioning and soil evolution within the frame of global change. We also need to share in a common frame our visions of soil functioning at various scales, one the one hand to strengthen our collaborations, and, on the other hand, to make them visible by the other communities working on environmental issues. The presentation will briefly present the VSoil platform. The platform is able to manipulate concepts and numerical representations of these processes. The tool helps in assembling modules to create a model and automatically generates an executable code and a GUI. Potentialities of the tool will be illustrated on few selected cases.

  6. Decision Support for Environmental Management of Industrial ...

    EPA Pesticide Factsheets

    Non-hazardous solid materials from industrial processes, once regarded as waste and disposed in landfills, offer numerous environmental and economic advantages when put to beneficial uses (BUs). Proper management of these industrial non-hazardous secondary materials (INSM) requires estimates of their probable environmental impacts among disposal as well as BU options. The U.S. Environmental Protection Agency (EPA) has recently approved new analytical methods (EPA Methods 1313–1316) to assess leachability of constituents of potential concern in these materials. These new methods are more realistic for many disposal and BU options than historical methods, such as the toxicity characteristic leaching protocol. Experimental data from these new methods are used to parameterize a chemical fate and transport (F&T) model to simulate long-term environmental releases from flue gas desulfurization gypsum (FGDG) when disposed of in an industrial landfill or beneficially used as an agricultural soil amendment. The F&T model is also coupled with optimization algorithms, the Beneficial Use Decision Support System (BUDSS), under development by EPA to enhance INSM management. The objective of this paper is to demonstrate the methodologies and encourage similar applications to improve environmental management and BUs of INSM through F&T simulation coupled with optimization, using realistic model parameterization.

  7. Environmental Adaptations, Ecological Filtering, and Dispersal Central to Insect Invasions.

    PubMed

    Renault, David; Laparie, Mathieu; McCauley, Shannon J; Bonte, Dries

    2018-01-07

    Insect invasions, the establishment and spread of nonnative insects in new regions, can have extensive economic and environmental consequences. Increased global connectivity accelerates rates of introductions, while climate change may decrease the barriers to invader species' spread. We follow an individual-level insect- and arachnid-centered perspective to assess how the process of invasion is influenced by phenotypic heterogeneity associated with dispersal and stress resistance, and their coupling, across the multiple steps of the invasion process. We also provide an overview and synthesis on the importance of environmental filters during the entire invasion process for the facilitation or inhibition of invasive insect population spread. Finally, we highlight important research gaps and the relevance and applicability of ongoing natural range expansions in the context of climate change to gain essential mechanistic insights into insect invasions.

  8. Development of a Coupled Hydrological/Sediment Yield Model for a Watershed at Regional Level

    NASA Technical Reports Server (NTRS)

    Rajbhandaril, Narayan; Crosson, William; Tsegaye, Teferi; Coleman, Tommy; Liu, Yaping; Soman, Vishwas

    1998-01-01

    Development of a hydrologic model for the study of environmental conservation requires a comprehensive understanding of individual-storm affecting hydrologic and sedimentologic processes. The hydrologic models that we are currently coupling are the Simulator for Hydrology and Energy Exchange at the Land Surface (SHEELS) and the Distributed Runoff Model (DRUM). SHEELS runs continuously to estimate surface energy fluxes and sub-surface soil water fluxes, while DRUM operates during and following precipitation events to predict surface runoff and peak flow through channel routing. The lateral re-distribution of surface water determined by DRUM is passed to SHEELS, which then adjusts soil water contents throughout the profile. The model SHEELS is well documented in Smith et al. (1993) and Laymen and Crosson (1995). The model DRUM is well documented in Vieux et al. (1990) and Vieux and Gauer (1994). The coupled hydrologic model, SHEELS/DRUM, does not simulate sedimentologic processes. The simulation of the sedimentologic process is important for environmental conservation planning and management. Therefore, we attempted to develop a conceptual frame work for coupling a sediment yield model with SHEELS/DRUM to estimate individual-storm sediment yield from a watershed at a regional level. The sediment yield model that will be used for this study is the Universal Soil Loss Equation (USLE) with some modifications to enable the model to predict individual-storm sediment yield. The predicted sediment yield does not include wind erosion and erosion caused by irrigation and snow melt. Units used for this study are those given by Foster et al. (1981) for SI units.

  9. Sonochemistry in environmental remediation. 1. Combinative and hybrid sonophotochemical oxidation processes for the treatment of pollutants in water.

    PubMed

    Adewuyi, Yusuf G

    2005-05-15

    Sonoprocessing is the utilization of sonic and ultrasonic waves in chemical synthesis and processes. It is a new and rapidly growing research field with broad applications in environmental engineering, green chemical synthesis, and processing. The application of this environmentally benign technique in environmental remediation is currently under active research and development. Sonochemical oxidation is effective in treating toxic effluents and reducing toxicity. However, the ultrasonic treatment is highly energy intensive since sonication is relatively inefficient with respect to total input energy and is therefore not economically attractive or feasible alone. Hence, sonochemistry has not yet received much attention as an alternative for industrial and large-scale chemical and environmental processes. One of the most interesting topics in the recent advances in sonochemistry is the possibility of double or more excitations with ultrasound and other types of energy. The coupling of ultrasound with other free energy sources (i.e., UV) or chemical oxidation utilizing H2O2, O3, or ferrous ion presents interesting and attractive approaches. Therefore, many recent efforts have been devoted to improving the efficiency of sonochemical reactions by exploiting the advantages of combinative or hybrid processes involving the simultaneous or sequential use of ultrasonic irradiation and other advanced oxidation processes, electrochemical processes, and biological treatment. This paper provides a critical review of the applications of ultrasound in environmental remediation, focusing on recent developments and unifying analysis of combinative or hybrid systems, namely, sonophotochemical oxidation processes.

  10. A hydromorphological framework for the evaluation of e-flows

    NASA Astrophysics Data System (ADS)

    Bussettini, Martina; Rinaldi, Massimo; Grant, Gordon

    2017-04-01

    Anthropogenic alteration of hydromorphological processes in rivers is a major factor that diminishes river health and undermines environmental objectives envisaged by river protection policies. Specifying environmental flows to address those impacts can be a key strategy for the maintenance of functional river processes and the achievement of those objectives. Environmental flows are determined by various methods and approaches, based primarily on hydrological and/or hydraulic evaluations, although holistic methodologies, considering the many interacting factors that structure aquatic ecosystems, including sediments, are increasingly used. Hydrological and geomorphological processes are highly coupled and any change in one typically affects the other. The coupling varies over different spatial and temporal scales, and changing either hydrological or geomorphological processes can result in alteration of river habitats, ultimately impacting ecological processes. In spite of these linkages, current restoration approaches typically focus only on changes on hydrological regime as a means promoting ecological enhancements. Neglecting sediment transport and its interaction with flow in shaping riverine habitats is likely to results not only in minor or no enhancements in the ecology, but may also increase the costs of water use. A more integrated view of how human activities jointly affect sediment regime, river morphology and river flows is therefore needed in order to determine the most effective actions to rehabilitate river processes to desired states. These states involve considerations of the combination of intrinsic ("natural") conditions (e.g. river sensitivity and morphological potential, off-site conditions) and socio-economic constraints. The evaluation of such factors, the analysis of different scenarios, and the selection of appropriate actions require the contextualization of river reaches within a wider spatial-temporal hydromorphological framework. Here we present such a general multiscale, process-based hydromorphological framework, and discuss its application to the problem of how best to analyse and estimate e-flows.

  11. QSAR ANALYSIS OF SORPTION-CORRECTED RATE CONSTANTS FOR REDUCTIVE BIOTRANSFORMATION OF HALOGENATED AROMATICS

    EPA Science Inventory

    The inherent coupling among geochemical and microbial reactions may have significant effects on the environmental fate of a containinant. For example, sorption processes may decrease the concentration of an organic compound in solution, thereby reducing the biodegradation rate of...

  12. New parsimonious simulation methods and tools to assess future food and environmental security of farm populations

    PubMed Central

    Antle, John M.; Stoorvogel, Jetse J.; Valdivia, Roberto O.

    2014-01-01

    This article presents conceptual and empirical foundations for new parsimonious simulation models that are being used to assess future food and environmental security of farm populations. The conceptual framework integrates key features of the biophysical and economic processes on which the farming systems are based. The approach represents a methodological advance by coupling important behavioural processes, for example, self-selection in adaptive responses to technological and environmental change, with aggregate processes, such as changes in market supply and demand conditions or environmental conditions as climate. Suitable biophysical and economic data are a critical limiting factor in modelling these complex systems, particularly for the characterization of out-of-sample counterfactuals in ex ante analyses. Parsimonious, population-based simulation methods are described that exploit available observational, experimental, modelled and expert data. The analysis makes use of a new scenario design concept called representative agricultural pathways. A case study illustrates how these methods can be used to assess food and environmental security. The concluding section addresses generalizations of parametric forms and linkages of regional models to global models. PMID:24535388

  13. New parsimonious simulation methods and tools to assess future food and environmental security of farm populations.

    PubMed

    Antle, John M; Stoorvogel, Jetse J; Valdivia, Roberto O

    2014-04-05

    This article presents conceptual and empirical foundations for new parsimonious simulation models that are being used to assess future food and environmental security of farm populations. The conceptual framework integrates key features of the biophysical and economic processes on which the farming systems are based. The approach represents a methodological advance by coupling important behavioural processes, for example, self-selection in adaptive responses to technological and environmental change, with aggregate processes, such as changes in market supply and demand conditions or environmental conditions as climate. Suitable biophysical and economic data are a critical limiting factor in modelling these complex systems, particularly for the characterization of out-of-sample counterfactuals in ex ante analyses. Parsimonious, population-based simulation methods are described that exploit available observational, experimental, modelled and expert data. The analysis makes use of a new scenario design concept called representative agricultural pathways. A case study illustrates how these methods can be used to assess food and environmental security. The concluding section addresses generalizations of parametric forms and linkages of regional models to global models.

  14. Long term observation and validation of windsat soil moisture data

    USDA-ARS?s Scientific Manuscript database

    The surface soil moisture controls surface energy budget. It is a key environmental variable in the coupled atmospheric and hydrological processes that are related to drought, heat waves and monsoon formation. Satellite remote sensing of soil moisture provides information that can contribute to unde...

  15. Acoustic mode coupling induced by shallow water nonlinear internal waves: sensitivity to environmental conditions and space-time scales of internal waves.

    PubMed

    Colosi, John A

    2008-09-01

    While many results have been intuited from numerical simulation studies, the precise connections between shallow-water acoustic variability and the space-time scales of nonlinear internal waves (NLIWs) as well as the background environmental conditions have not been clearly established analytically. Two-dimensional coupled mode propagation through NLIWs is examined using a perturbation series solution in which each order n is associated with nth-order multiple scattering. Importantly, the perturbation solution gives resonance conditions that pick out specific NLIW scales that cause coupling, and seabed attenuation is demonstrated to broaden these resonances, fundamentally changing the coupling behavior at low frequency. Sound-speed inhomogeneities caused by internal solitary waves (ISWs) are primarily considered and the dependence of mode coupling on ISW amplitude, range width, depth structure, location relative to the source, and packet characteristics are delineated as a function of acoustic frequency. In addition, it is seen that significant energy transfer to modes with initially low or zero energy involves at least a second order scattering process. Under moderate scattering conditions, comparisons of first order, single scattering theoretical predictions to direct numerical simulation demonstrate the accuracy of the approach for acoustic frequencies upto 400 Hz and for single as well as multiple ISW wave packets.

  16. Using Wavelets and Information Theory to Characterize the Direction, Strength, and Time Scale of Interaction between Environmental Drivers and Greenhouse Gas Exchange in Managed Wetlands of Northern California

    NASA Astrophysics Data System (ADS)

    Sturtevant, C. S.; Ruddell, B. L.; Knox, S. H.; Verfaillie, J. G.; Matthes, J. H.; Oikawa, P. Y.; Baldocchi, D. D.

    2014-12-01

    Restoring agricultural areas to wetlands in the Sacramento-San Joaquin River Delta of California can help reverse subsidence and reduce greenhouse gas (GHG) emissions. Predicting outcomes and developing best practices of wetland management therefore requires a robust understanding of the sensitivity of GHG exchange in these ecosystems to factors such as management and meteorology. However, wetlands can exhibit complex, overlapping, and asynchronous couplings between site characteristics, environmental drivers and GHG exchange. In this research we demonstrate the use of wavelets and information theory (process networks) as sophisticated tools to disentangle and characterize ecosystem couplings to CO2 and CH4 exchange (measured by eddy covariance) in two restored Delta wetlands. Using wavelets we isolated processes acting at different time scales, then used process networks to determine the direction, strength, and lag properties of ecosystem couplings. We found that despite differences in age, architecture and management, CO2 exchange at both wetlands was most sensitive to similar meteorological factors such as radiation and temperature up to a time scale of several days. At the monthly timescale, however, the effect of a more variable water table management in one wetland became dominant, revealing a reduction in net CO2 uptake during long term water table drawdowns. The analysis of CH4 exchange in this wetland revealed a more sensitive and complex coupling with water table. CH4 exchange was sensitive to relatively small, multi-day shifts in water table and displayed a lagged response to larger, longer shifts. With these methods we were able to disentangle the effects of management from meteorology and better understand the sensitivities of GHG exchange. Our results provide important insights for modeling efforts and management practices.

  17. Development of a Mobile Tracer Correlation Techniques for Assessment of Air Emissions from Landfills and Other Area Sources

    EPA Science Inventory

    Improved understanding of air emissions from large area sources such as landfills, waste water ponds, open-source processing, and agricultural operations is a topic of increasing environmental importance. In many cases, the size of the area source, coupled with spatial-heteroge...

  18. A revised framework for coupled human and natural systems, propagating thresholds, and managing environmental problems

    NASA Astrophysics Data System (ADS)

    Stevenson, R. Jan

    Frameworks for solving environmental problems have been presented over the past 40 years from many organizations and disciplines, often with a strong focus on their own discipline. This paper describes a modification of an existing framework that can be better applied to manage environmental problems. Human well being, environmental policy, human activities, stressors (contaminants and habitat alterations), and ecosystem services are highlighted as five elements of the coupled human and natural system in the proposed framework. Thresholds in relationships among elements in coupled human and natural systems are key attributes of couplings because of their use in development of environmental criteria by facilitating stakeholder consensus and preventing catastrophic changes. Propagation of thresholds through coupled human and natural systems is hypothesized to be a significant driver of policy development. The application of the framework is related to managing eutrophication and algal bloom problems.

  19. Redox reaction characteristics of riboflavin: a fluorescence spectroelectrochemical analysis and density functional theory calculation.

    PubMed

    Chen, Wei; Chen, Jie-Jie; Lu, Rui; Qian, Chen; Li, Wen-Wei; Yu, Han-Qing

    2014-08-01

    Riboflavin (RF), the primary redox active component of flavin, is involved in many redox processes in biogeochemical systems. Despite of its wide distribution and important roles in environmental remediation, its redox behaviors and reaction mechanisms in hydrophobic sites remain unclear yet. In this study, spectroelectrochemical analysis and density functional theory (DFT) calculation were integrated to explore the redox behaviors of RF in dimethyl sulfoxide (DMSO), which was used to create a hydrophobic environment. Specifically, cyclic voltafluorometry (CVF) and derivative cyclic voltafluorometry (DCVF) were employed to track the RF concentration changing profiles. It was found that the reduction contained a series of proton-coupled electron transfers dependent of potential driving force. In addition to the electron transfer-chemical reaction-electron transfer process, a disproportionation (DISP1) process was also identified to be involved in the reduction. The redox potential and free energy of each step obtained from the DFT calculations further confirmed the mechanisms proposed based on the experimental results. The combination of experimental and theoretical approaches yields a deep insight into the characteristics of RF in environmental remediation and better understanding about the proton-coupled electron transfer mechanisms. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Development of Chemical Process Design and Control for ...

    EPA Pesticide Factsheets

    This contribution describes a novel process systems engineering framework that couples advanced control with sustainability evaluation and decision making for the optimization of process operations to minimize environmental impacts associated with products, materials, and energy. The implemented control strategy combines a biologically inspired method with optimal control concepts for finding more sustainable operating trajectories. The sustainability assessment of process operating points is carried out by using the U.S. E.P.A.’s Gauging Reaction Effectiveness for the ENvironmental Sustainability of Chemistries with a multi-Objective Process Evaluator (GREENSCOPE) tool that provides scores for the selected indicators in the economic, material efficiency, environmental and energy areas. The indicator scores describe process performance on a sustainability measurement scale, effectively determining which operating point is more sustainable if there are more than several steady states for one specific product manufacturing. Through comparisons between a representative benchmark and the optimal steady-states obtained through implementation of the proposed controller, a systematic decision can be made in terms of whether the implementation of the controller is moving the process towards a more sustainable operation. The effectiveness of the proposed framework is illustrated through a case study of a continuous fermentation process for fuel production, whose materi

  1. Ultra-trace determination of gold nanoparticles in environmental water by surfactant assisted dispersive liquid liquid microextraction coupled with electrothermal vaporization-inductively coupled plasma-mass spectrometry

    NASA Astrophysics Data System (ADS)

    Liu, Ying; He, Man; Chen, Beibei; Hu, Bin

    2016-08-01

    A new method by coupling surfactant assisted dispersive liquid liquid microextraction (SA-DLLME) with electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) was proposed for the analysis of gold nanoparticles (AuNPs) in environmental water samples. Effective separation of AuNPs from ionic gold species was achieved by using sodium thiosulphate as a complexing agent. Various experimental parameters affecting SA-DLLME of AuNPs, such as the organic solvent, organic solvent volume, pH of the sample, the kind of surfactant, surfactant concentration, vortex time, speed of centrifugation, centrifugation time, and different coating as well as sizes of AuNPs were investigated carefully. Furthermore, the interference of coexisting ions, dissolved organic matter (DOM) and other metal nanoparticles (NPs) were studied. Under the optimal conditions, a detection limit of 2.2 ng L- 1 and an enrichment factor of 152-fold was achieved for AuNPs, and the original morphology of the AuNPs could be maintained during the extraction process. The developed method was successfully applied for the analysis of AuNPs in environmental water samples, including tap water, the East Lake water, and the Yangtze River water, with recoveries in the range of 89.6-102%. Compared with the established methods for metal NPs analysis, the proposed method has the merits of simple and fast operation, low detection limit, high selectivity, good tolerance to the sample matrix and no digestion or dilution required. It provides an efficient quantification methodology for monitoring AuNPs' pollution in the environmental water and evaluating its toxicity.

  2. A Unified Data Assimilation Strategy for Regional Coupled Atmosphere-Ocean Prediction Systems

    NASA Astrophysics Data System (ADS)

    Xie, Lian; Liu, Bin; Zhang, Fuqing; Weng, Yonghui

    2014-05-01

    Improving tropical cyclone (TC) forecasts is a top priority in weather forecasting. Assimilating various observational data to produce better initial conditions for numerical models using advanced data assimilation techniques has been shown to benefit TC intensity forecasts, whereas assimilating large-scale environmental circulation into regional models by spectral nudging or Scale-Selective Data Assimilation (SSDA) has been demonstrated to improve TC track forecasts. Meanwhile, taking into account various air-sea interaction processes by high-resolution coupled air-sea modelling systems has also been shown to improve TC intensity forecasts. Despite the advances in data assimilation and air-sea coupled models, large errors in TC intensity and track forecasting remain. For example, Hurricane Nate (2011) has brought considerable challenge for the TC operational forecasting community, with very large intensity forecast errors (27, 25, and 40 kts for 48, 72, and 96 h, respectively) for the official forecasts. Considering the slow-moving nature of Hurricane Nate, it is reasonable to hypothesize that air-sea interaction processes played a critical role in the intensity change of the storm, and accurate representation of the upper ocean dynamics and thermodynamics is necessary to quantitatively describe the air-sea interaction processes. Currently, data assimilation techniques are generally only applied to hurricane forecasting in stand-alone atmospheric or oceanic model. In fact, most of the regional hurricane forecasting models only included data assimilation techniques for improving the initial condition of the atmospheric model. In such a situation, the benefit of adjustments in one model (atmospheric or oceanic) by assimilating observational data can be compromised by errors from the other model. Thus, unified data assimilation techniques for coupled air-sea modelling systems, which not only simultaneously assimilate atmospheric and oceanic observations into the coupled air-sea modelling system, but also nudging the large-scale environmental flow in the regional model towards global model forecasts are of increasing necessity. In this presentation, we will outline a strategy for an integrated approach in air-sea coupled data assimilation and discuss its benefits and feasibility from incremental results for select historical hurricane cases.

  3. Development of a zoning-based environmental-ecological-coupled model for lakes to assess lake restoration effect

    NASA Astrophysics Data System (ADS)

    Xu, Mengjia; Zou, Changxin; Zhao, Yanwei

    2017-04-01

    Environmental/ecological models are widely used for lake management as they provide a means to understand physical, chemical and biological processes in highly complex ecosystems. Most research focused on the development of environmental (water quality) and ecological models, separately. Limited studies were developed to couple the two models, and in these limited coupled models, a lake was regarded as a whole for analysis (i.e., considering the lake to be one well-mixed box), which was appropriate for small-scale lakes and was not sufficient to capture spatial variations within middle-scale or large-scale lakes. This paper seeks to establish a zoning-based environmental-ecological-coupled model for a lake. The Baiyangdian Lake, the largest freshwater lake in Northern China, was adopted as the study case. The coupled lake models including a hydrodynamics and water quality model established by MIKE21 and a compartmental ecological model used STELLA software have been established for middle-sized Baiyangdian Lake to realize the simulation of spatial variations of ecological conditions. On the basis of the flow field distribution results generated by MIKE21 hydrodynamics model, four water area zones were used as an example for compartmental ecological model calibration and validation. The results revealed that the developed coupled lake models can reasonably reflected the changes of the key state variables although there remain some state variables that are not well represented by the model due to the low quality of field monitoring data. Monitoring sites in a compartment may not be representative of the water quality and ecological conditions in the entire compartment even though that is the intention of compartment-based model design. There was only one ecological observation from a single monitoring site for some periods. This single-measurement issue may cause large discrepancies particularly when sampled site is not representative of the whole compartment. The coupled models have been applied to simulate the spatial variation trends of ecological condition under ecological water supplement as an example to reflect the application effect in lake restoration and management. The simulation results indicate that the models can provide a useful tool for lake restoration and management. The simulated spatial variation trends can provide a foundation for establishing permissible ranges for a selected set of water quality indices for a series of management measures such as watershed pollution load control and ecological water transfer. Meanwhile, the coupled models can help us to understand processes taking place and the relations of interaction between components in the lake ecosystem and external conditions. Taken together, the proposed models we established show some promising applications as middle-scale or large-scale lake management tools for pollution load control and ecological water transfer. These tools quantify the implications of proposed future water management decisions.

  4. Contrasting Microbial Community Assembly Hypotheses: A Reconciling Tale from the Río Tinto

    PubMed Central

    Palacios, Carmen; Zettler, Erik; Amils, Ricardo; Amaral-Zettler, Linda

    2008-01-01

    Background The Río Tinto (RT) is distinguished from other acid mine drainage systems by its natural and ancient origins. Microbial life from all three domains flourishes in this ecosystem, but bacteria dominate metabolic processes that perpetuate environmental extremes. While the patchy geochemistry of the RT likely influences the dynamics of bacterial populations, demonstrating which environmental variables shape microbial diversity and unveiling the mechanisms underlying observed patterns, remain major challenges in microbial ecology whose answers rely upon detailed assessments of community structures coupled with fine-scale measurements of physico-chemical parameters. Methodology/Principal Findings By using high-throughput environmental tag sequencing we achieved saturation of richness estimators for the first time in the RT. We found that environmental factors dictate the distribution of the most abundant taxa in this system, but stochastic niche differentiation processes, such as mutation and dispersal, also contribute to observed diversity patterns. Conclusions/Significance We predict that studies providing clues to the evolutionary and ecological processes underlying microbial distributions will reconcile the ongoing debate between the Baas Becking vs. Hubbell community assembly hypotheses. PMID:19052647

  5. Contrasting microbial community assembly hypotheses: a reconciling tale from the Río Tinto.

    PubMed

    Palacios, Carmen; Zettler, Erik; Amils, Ricardo; Amaral-Zettler, Linda

    2008-01-01

    The Río Tinto (RT) is distinguished from other acid mine drainage systems by its natural and ancient origins. Microbial life from all three domains flourishes in this ecosystem, but bacteria dominate metabolic processes that perpetuate environmental extremes. While the patchy geochemistry of the RT likely influences the dynamics of bacterial populations, demonstrating which environmental variables shape microbial diversity and unveiling the mechanisms underlying observed patterns, remain major challenges in microbial ecology whose answers rely upon detailed assessments of community structures coupled with fine-scale measurements of physico-chemical parameters. By using high-throughput environmental tag sequencing we achieved saturation of richness estimators for the first time in the RT. We found that environmental factors dictate the distribution of the most abundant taxa in this system, but stochastic niche differentiation processes, such as mutation and dispersal, also contribute to observed diversity patterns. We predict that studies providing clues to the evolutionary and ecological processes underlying microbial distributions will reconcile the ongoing debate between the Baas Becking vs. Hubbell community assembly hypotheses.

  6. A Benchmarking Initiative for Reactive Transport Modeling Applied to Subsurface Environmental Applications

    NASA Astrophysics Data System (ADS)

    Steefel, C. I.

    2015-12-01

    Over the last 20 years, we have seen the evolution of multicomponent reactive transport modeling and the expanding range and increasing complexity of subsurface environmental applications it is being used to address. Reactive transport modeling is being asked to provide accurate assessments of engineering performance and risk for important issues with far-reaching consequences. As a result, the complexity and detail of subsurface processes, properties, and conditions that can be simulated have significantly expanded. Closed form solutions are necessary and useful, but limited to situations that are far simpler than typical applications that combine many physical and chemical processes, in many cases in coupled form. In the absence of closed form and yet realistic solutions for complex applications, numerical benchmark problems with an accepted set of results will be indispensable to qualifying codes for various environmental applications. The intent of this benchmarking exercise, now underway for more than five years, is to develop and publish a set of well-described benchmark problems that can be used to demonstrate simulator conformance with norms established by the subsurface science and engineering community. The objective is not to verify this or that specific code--the reactive transport codes play a supporting role in this regard—but rather to use the codes to verify that a common solution of the problem can be achieved. Thus, the objective of each of the manuscripts is to present an environmentally-relevant benchmark problem that tests the conceptual model capabilities, numerical implementation, process coupling, and accuracy. The benchmark problems developed to date include 1) microbially-mediated reactions, 2) isotopes, 3) multi-component diffusion, 4) uranium fate and transport, 5) metal mobility in mining affected systems, and 6) waste repositories and related aspects.

  7. CORONA-INDUCED OZONATION COUPLED WITH PHOTOOXIDATION: AN ENVIRONMENTALLY FRIENDLY AND COST-EFFECTIVE METHOD

    EPA Science Inventory

    We have developed a process that uses surface corona for the production of ozone by passing air or oxygen through a high voltage electrical discharge and the emitted ultraviolet light is being used to activate a photocatalyst. A thin film of nanostructured TiO2 with primary part...

  8. A Hybrid Multiscale Framework for Subsurface Flow and Transport Simulations

    DOE PAGES

    Scheibe, Timothy D.; Yang, Xiaofan; Chen, Xingyuan; ...

    2015-06-01

    Extensive research efforts have been invested in reducing model errors to improve the predictive ability of biogeochemical earth and environmental system simulators, with applications ranging from contaminant transport and remediation to impacts of biogeochemical elemental cycling (e.g., carbon and nitrogen) on local ecosystems and regional to global climate. While the bulk of this research has focused on improving model parameterizations in the face of observational limitations, the more challenging type of model error/uncertainty to identify and quantify is model structural error which arises from incorrect mathematical representations of (or failure to consider) important physical, chemical, or biological processes, properties, ormore » system states in model formulations. While improved process understanding can be achieved through scientific study, such understanding is usually developed at small scales. Process-based numerical models are typically designed for a particular characteristic length and time scale. For application-relevant scales, it is generally necessary to introduce approximations and empirical parameterizations to describe complex systems or processes. This single-scale approach has been the best available to date because of limited understanding of process coupling combined with practical limitations on system characterization and computation. While computational power is increasing significantly and our understanding of biological and environmental processes at fundamental scales is accelerating, using this information to advance our knowledge of the larger system behavior requires the development of multiscale simulators. Accordingly there has been much recent interest in novel multiscale methods in which microscale and macroscale models are explicitly coupled in a single hybrid multiscale simulation. A limited number of hybrid multiscale simulations have been developed for biogeochemical earth systems, but they mostly utilize application-specific and sometimes ad-hoc approaches for model coupling. We are developing a generalized approach to hierarchical model coupling designed for high-performance computational systems, based on the Swift computing workflow framework. In this presentation we will describe the generalized approach and provide two use cases: 1) simulation of a mixing-controlled biogeochemical reaction coupling pore- and continuum-scale models, and 2) simulation of biogeochemical impacts of groundwater – river water interactions coupling fine- and coarse-grid model representations. This generalized framework can be customized for use with any pair of linked models (microscale and macroscale) with minimal intrusiveness to the at-scale simulators. It combines a set of python scripts with the Swift workflow environment to execute a complex multiscale simulation utilizing an approach similar to the well-known Heterogeneous Multiscale Method. User customization is facilitated through user-provided input and output file templates and processing function scripts, and execution within a high-performance computing environment is handled by Swift, such that minimal to no user modification of at-scale codes is required.« less

  9. Impact of stride-coupled gaze shifts of walking blowflies on the neuronal representation of visual targets

    PubMed Central

    Kress, Daniel; Egelhaaf, Martin

    2014-01-01

    During locomotion animals rely heavily on visual cues gained from the environment to guide their behavior. Examples are basic behaviors like collision avoidance or the approach to a goal. The saccadic gaze strategy of flying flies, which separates translational from rotational phases of locomotion, has been suggested to facilitate the extraction of environmental information, because only image flow evoked by translational self-motion contains relevant distance information about the surrounding world. In contrast to the translational phases of flight during which gaze direction is kept largely constant, walking flies experience continuous rotational image flow that is coupled to their stride-cycle. The consequences of these self-produced image shifts for the extraction of environmental information are still unclear. To assess the impact of stride-coupled image shifts on visual information processing, we performed electrophysiological recordings from the HSE cell, a motion sensitive wide-field neuron in the blowfly visual system. This cell has been concluded to play a key role in mediating optomotor behavior, self-motion estimation and spatial information processing. We used visual stimuli that were based on the visual input experienced by walking blowflies while approaching a black vertical bar. The response of HSE to these stimuli was dominated by periodic membrane potential fluctuations evoked by stride-coupled image shifts. Nevertheless, during the approach the cell’s response contained information about the bar and its background. The response components evoked by the bar were larger than the responses to its background, especially during the last phase of the approach. However, as revealed by targeted modifications of the visual input during walking, the extraction of distance information on the basis of HSE responses is much impaired by stride-coupled retinal image shifts. Possible mechanisms that may cope with these stride-coupled responses are discussed. PMID:25309362

  10. The Modular Modeling System (MMS): A modeling framework for water- and environmental-resources management

    USGS Publications Warehouse

    Leavesley, G.H.; Markstrom, S.L.; Viger, R.J.

    2004-01-01

    The interdisciplinary nature and increasing complexity of water- and environmental-resource problems require the use of modeling approaches that can incorporate knowledge from a broad range of scientific disciplines. The large number of distributed hydrological and ecosystem models currently available are composed of a variety of different conceptualizations of the associated processes they simulate. Assessment of the capabilities of these distributed models requires evaluation of the conceptualizations of the individual processes, and the identification of which conceptualizations are most appropriate for various combinations of criteria, such as problem objectives, data constraints, and spatial and temporal scales of application. With this knowledge, "optimal" models for specific sets of criteria can be created and applied. The U.S. Geological Survey (USGS) Modular Modeling System (MMS) is an integrated system of computer software that has been developed to provide these model development and application capabilities. MMS supports the integration of models and tools at a variety of levels of modular design. These include individual process models, tightly coupled models, loosely coupled models, and fully-integrated decision support systems. A variety of visualization and statistical tools are also provided. MMS has been coupled with the Bureau of Reclamation (BOR) object-oriented reservoir and river-system modeling framework, RiverWare, under a joint USGS-BOR program called the Watershed and River System Management Program. MMS and RiverWare are linked using a shared relational database. The resulting database-centered decision support system provides tools for evaluating and applying optimal resource-allocation and management strategies to complex, operational decisions on multipurpose reservoir systems and watersheds. Management issues being addressed include efficiency of water-resources management, environmental concerns such as meeting flow needs for endangered species, and optimizing operations within the constraints of multiple objectives such as power generation, irrigation, and water conservation. This decision support system approach is being developed, tested, and implemented in the Gunni-son, Yakima, San Juan, Rio Grande, and Truckee River basins of the western United States. Copyright ASCE 2004.

  11. Predicting photosynthesis and transpiration responses to ozone: decoupling modeled photosynthesis and stomatal conductance

    NASA Astrophysics Data System (ADS)

    Lombardozzi, D.; Levis, S.; Bonan, G.; Sparks, J. P.

    2012-08-01

    Plants exchange greenhouse gases carbon dioxide and water with the atmosphere through the processes of photosynthesis and transpiration, making them essential in climate regulation. Carbon dioxide and water exchange are typically coupled through the control of stomatal conductance, and the parameterization in many models often predict conductance based on photosynthesis values. Some environmental conditions, like exposure to high ozone (O3) concentrations, alter photosynthesis independent of stomatal conductance, so models that couple these processes cannot accurately predict both. The goals of this study were to test direct and indirect photosynthesis and stomatal conductance modifications based on O3 damage to tulip poplar (Liriodendron tulipifera) in a coupled Farquhar/Ball-Berry model. The same modifications were then tested in the Community Land Model (CLM) to determine the impacts on gross primary productivity (GPP) and transpiration at a constant O3 concentration of 100 parts per billion (ppb). Modifying the Vcmax parameter and directly modifying stomatal conductance best predicts photosynthesis and stomatal conductance responses to chronic O3 over a range of environmental conditions. On a global scale, directly modifying conductance reduces the effect of O3 on both transpiration and GPP compared to indirectly modifying conductance, particularly in the tropics. The results of this study suggest that independently modifying stomatal conductance can improve the ability of models to predict hydrologic cycling, and therefore improve future climate predictions.

  12. Design of Soil Salinity Policies with Tinamit, a Flexible and Rapid Tool to Couple Stakeholder-Built System Dynamics Models with Physically-Based Models

    NASA Astrophysics Data System (ADS)

    Malard, J. J.; Baig, A. I.; Hassanzadeh, E.; Adamowski, J. F.; Tuy, H.; Melgar-Quiñonez, H.

    2016-12-01

    Model coupling is a crucial step to constructing many environmental models, as it allows for the integration of independently-built models representing different system sub-components to simulate the entire system. Model coupling has been of particular interest in combining socioeconomic System Dynamics (SD) models, whose visual interface facilitates their direct use by stakeholders, with more complex physically-based models of the environmental system. However, model coupling processes are often cumbersome and inflexible and require extensive programming knowledge, limiting their potential for continued use by stakeholders in policy design and analysis after the end of the project. Here, we present Tinamit, a flexible Python-based model-coupling software tool whose easy-to-use API and graphical user interface make the coupling of stakeholder-built SD models with physically-based models rapid, flexible and simple for users with limited to no coding knowledge. The flexibility of the system allows end users to modify the SD model as well as the linking variables between the two models themselves with no need for recoding. We use Tinamit to couple a stakeholder-built socioeconomic model of soil salinization in Pakistan with the physically-based soil salinity model SAHYSMOD. As climate extremes increase in the region, policies to slow or reverse soil salinity buildup are increasing in urgency and must take both socioeconomic and biophysical spheres into account. We use the Tinamit-coupled model to test the impact of integrated policy options (economic and regulatory incentives to farmers) on soil salinity in the region in the face of future climate change scenarios. Use of the Tinamit model allowed for rapid and flexible coupling of the two models, allowing the end user to continue making model structure and policy changes. In addition, the clear interface (in contrast to most model coupling code) makes the final coupled model easily accessible to stakeholders with limited technical background.

  13. Can the black box be cracked? The augmentation of microbial ecology by high-resolution, automated sensing technologies.

    PubMed

    Shade, Ashley; Carey, Cayelan C; Kara, Emily; Bertilsson, Stefan; McMahon, Katherine D; Smith, Matthew C

    2009-08-01

    Automated sensing technologies, 'ASTs,' are tools that can monitor environmental or microbial-related variables at increasingly high temporal resolution. Microbial ecologists are poised to use AST data to couple microbial structure, function and associated environmental observations on temporal scales pertinent to microbial processes. In the context of aquatic microbiology, we discuss three applications of ASTs: windows on the microbial world, adaptive sampling and adaptive management. We challenge microbial ecologists to push AST potential in helping to reveal relationships between microbial structure and function.

  14. Planning and implementing an honors degree in environmental science curricula: a case study from the University of Delaware, USA

    NASA Astrophysics Data System (ADS)

    Levia, Delphis

    2015-04-01

    Environmental degradation is undermining the sustainability of our planet. The multi-faceted nature of environmental stressors, which inherently couples human-environment interactions across space and time, necessitates that we train environmental scientists holistically within an interdisciplinary framework. Recruiting top-notch honors students to major in the environmental sciences is a critical step to ensure that we have the human capital to tackle complicated environmental problems successfully. Planning and implementing an honors degree is no trivial task. Based upon a recently completed and implemented set of programmatic revisions*, this poster showcases a successful example of an honors curriculum in environmental science to recruit and educate dynamic thinkers capable of improving the quality of our environment. The interdisciplinary environmental science program at the University of Delaware emphasizes the cross-cutting among earth's spheres through a core set of courses which employ a quantitative approach which is supplemented by several environmental policy courses. The core is coupled with six different thematic concentrations (students choose one) which permit the student to delve into a particular area of environmental science. The honors component of the degree consists of twelve additional credits. These credits are met through a specially designed introductory environmental course, a field experience requiring data collection, analysis, and write-up, a capstone course, and one other environmentally related course. The environmental sciences honors curriculum outlined in this poster may serve as a useful guide to others wishing to establish an honors program of their own in environmental science to recruit and prepare the next generation to mitigate environmental degradation. -------------- * Please note that the planning process for the environmental programs was and is the collective effort of many dedicated people. Current members of the advisory Environmental Council include Drs. Delphis Levia (Program Director & Chair), Nancy Targett (Dean), Frank Newton, Tracy Deliberty, Steve Hastings, John Madsen, Paul Imhoff, Jan Johnson, Jerry Kauffman, Murray Johnston.

  15. Flash flooding: Toward an Interdisciplinary and Integrated Strategy for Disaster Reduction in a Global Environmental Change Perspective

    NASA Astrophysics Data System (ADS)

    Ruin, Isabelle

    2014-05-01

    How do people answer to heavy precipitation and flood warnings? How do they adapt their daily schedule and activity to the fast evolution of the environmental circumstances? More generally, how do social processes interact with physical ones? Such questions address the dynamical interactions between hydro-meteorological variables, human perception and representation of the environment, and actual individual and social behavioral responses. It also poses the question of scales and hierarchy issues through seamless interactions between smaller and larger scales. These questions are relevant for both social and physical scientists. They are more and more pertinently addressed in the Global Environmental Change perspective through the concepts of Coupled Human And Natural Systems (CHANS), resilience or panarchy developped in the context of interdisciplinary collaborations. Nevertheless those concepts are complex and not easy to handle, specially when facing with operational goals. One of the main difficulty to advance these integrated approaches is the access to empirical data informing the processes at various scales. In fact, if physical and social processes are well studied by distinct disciplines, they are rarely jointly explored within similar spatial and temporal resolutions. Such coupled observation and analysis poses methodological challenges, specially when dealing with responses to short-fuse and extreme weather events. In fact, if such coupled approach is quite common to study large scale phenomenon like global change (for instance using historical data on green house gaz emissions and the evolution of temperatures worldwide), it is rarer for studing smaller nested sets of scales of human-nature systems where finer resolution data are sparse. Another problem arise from the need to produce comparable analysis on different case studies where social, physical and even cultural contexts may be diverse. Generic and robust framework for data collection, modeling and analysis are needed to allow cross comparison and deeper understanding of the processes accross scales. This presentation will address these issues based on concrete exemples from empirical studies on past flash flooding events across Europe and USA.

  16. Listeria monocytogenes cross-contamination of cheese: risk throughout the food supply chain.

    PubMed

    Sauders, B D; D'Amico, D J

    2016-10-01

    Listeria monocytogenes has been the most common microbial cause of cheese-related recalls in both the United States and Canada in recent years. Since L. monocytogenes is inactivated by pasteurization, the majority of these cases have been linked to environmental and cross-contamination of fresh-soft, soft-ripened, and semi-soft cheeses. Cross-contamination of foods with L. monocytogenes is a continuous risk throughout the food supply chain and presents unique challenges for subsequent illness and outbreak investigations. Reports on outbreaks of listeriosis attributed to cross-contamination downstream from primary processing help highlight the critical role of epidemiological investigation coupled with coordinated molecular subtyping and surveillance in the recognition and investigation of complex foodborne outbreaks. Despite their complexity, environmental sampling throughout the supply chain coupled with improved genotyping approaches and concomitant analysis of foodborne illness epidemiological exposure data are needed to help resolve these and similar cases more rapidly and with greater confidence.

  17. Alternatives for the intermediate recovery of plasmid DNA: performance, economic viability and environmental impact.

    PubMed

    Freitas, Sindelia; Canário, Sónia; Santos, José A L; Prazeres, Duarte M F

    2009-02-01

    Robust cGMP manufacturing is required to produce high-quality plasmid DNA (pDNA). Three established techniques, isopropanol and ammonium sulfate (AS) precipitation (PP), tangential flow filtration (TFF) and aqueous two-phase systems (ATPS) with PEG600/AS, were tested as alternatives to recover pDNA from alkaline lysates. Yield and purity data were used to evaluate the economic and environmental impact of each option. Although pDNA yields > or = 90% were always obtained, ATPS delivered the highest HPLC purity (59%), followed by PP (48%) and TFF (18%). However, the ability of ATPS to concentrate pDNA was very poor when compared with PP or TFF. Processes were also implemented by coupling TFF with ATPS or AS-PP. Process simulations indicate that all options require large amounts of water (100-200 tons/kg pDNA) and that the ATPS process uses large amounts of mass separating agents (65 tons/kg pDNA). Estimates indicate that operating costs of the ATPS process are 2.5-fold larger when compared with the PP and TFF processes. The most significant contributions to the costs in the PP, TFF and ATPS processes came from operators (59%), consumables (75%) and raw materials (84%), respectively. The ATPS process presented the highest environmental impact, whereas the impact of the TFF process was negligible.

  18. A finite element simulation of biological conversion processes in landfills.

    PubMed

    Robeck, M; Ricken, T; Widmann, R

    2011-04-01

    Landfills are the most common way of waste disposal worldwide. Biological processes convert the organic material into an environmentally harmful landfill gas, which has an impact on the greenhouse effect. After the depositing of waste has been stopped, current conversion processes continue and emissions last for several decades and even up to 100years and longer. A good prediction of these processes is of high importance for landfill operators as well as for authorities, but suitable models for a realistic description of landfill processes are rather poor. In order to take the strong coupled conversion processes into account, a constitutive three-dimensional model based on the multiphase Theory of Porous Media (TPM) has been developed at the University of Duisburg-Essen. The theoretical formulations are implemented in the finite element code FEAP. With the presented calculation concept we are able to simulate the coupled processes that occur in an actual landfill. The model's theoretical background and the results of the simulations as well as the meantime successfully performed simulation of a real landfill body will be shown in the following. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Coupling System Dynamics and Physically-based Models for Participatory Water Management - A Methodological Framework, with Two Case Studies: Water Quality in Quebec, and Soil Salinity in Pakistan

    NASA Astrophysics Data System (ADS)

    Boisvert-Chouinard, J.; Halbe, J.; Baig, A. I.; Adamowski, J. F.

    2014-12-01

    The principles of Integrated Water Resource Management outline the importance of stakeholder participation in water management processes, but in practice, there is a lack of meaningful engagement in water planning and implementation, and participation is often limited to public consultation and education. When models are used to support water planning, stakeholders are usually not involved in their development and use, and the models commonly fail to represent important feedbacks between socio-economic and physical processes. This paper presents the development of holistic models of the Du Chêne basin in Quebec, and the Rechna Doab basin in Pakistan, that simulate socio-economic and physical processes related to, respectively, water quality management, and soil salinity management. The models each consists of two sub-components: a System Dynamics (SD) model, and a physically based model. The SD component was developed in collaboration with key stakeholders in the basins. The Du Chêne SD model was coupled with a Soil and Water Assessment Tool (SWAT) model, while the Rechna Doab SD model was coupled with SahysMod, a soil salinity model. The coupled models were used to assess the environmental and socio-economic impacts of different management scenarios proposed by stakeholders. Results indicate that coupled SD - physically-based models can be used as effective tools for participatory water planning and implementation. The participatory modeling process provides a structure for meaningful stakeholder engagement, and the models themselves can be used to transparently and coherently assess and compare different management options.

  20. The Shale Hills Critical Zone Observatory for Embedded Sensing and Simulation

    NASA Astrophysics Data System (ADS)

    Duffy, C.; Davis, K.; Kane, T.; Boyer, E.

    2009-04-01

    The future of environmental observing systems will utilize embedded sensor networks with continuous real-time measurement of hydrologic, atmospheric, biogeochemical, and ecological variables across diverse terrestrial environments. Embedded environmental sensors, benefitting from advances in information sciences, networking technology, materials science, computing capacity, and data synthesis methods, are undergoing revolutionary change. It is now possible to field spatially-distributed, multi-node sensor networks that provide density and spatial coverage previously accessible only via numerical simulation. At the same time, computational tools are advancing rapidly to the point where it is now possible to simulate the physical processes controlling individual parcels of water and solutes through the complete terrestrial water cycle. Our goal for the Penn State Critical Zone Observatory is to apply environmental sensor arrays, integrated hydrologic models deployed and coordinated at a testbed within the Penn State Experimental Forest. The NSF-funded CZO is designed to observe the detailed space and time complexities of the water and energy cycle for a watershed and ultimately the river basin for all physical states and fluxes (groundwater, soil moisture, temperature, streamflow, latent heat, snowmelt, chemistry, isotopes etc.). Presently fully-coupled physical models are being developed that link the atmosphere-land-vegetation-subsurface system into a fully-coupled distributed system. During the last 5 years the Penn State Integrated Hydrologic Modeling System has been under development as an open-source community modeling project funded by NSF EAR/GEO and NSF CBET/ENG. PIHM represents a strategy for the formulation and solution of fully-coupled process equations at the watershed and river basin scales, and includes a tightly coupled GIS tool for data handling, domain decomposition, optimal unstructured grid generation, and model parameterization. (PIHM; http://sourceforge.net/projects/pihmmodel/; http://sourceforge.net/projects/pihmgis/ ) The CZO sensor and simulation system is being developed to have the following elements: 1) extensive, spatially-distributed smart sensor networks to gather intensive soil, geologic, hydrologic, geochemical and isotopic data; 2) spatially-explicit multiphysics models/solutions of the land-subsurface-vegetation-atmosphere system; and 3) parallel/distributed, adaptive algorithms for rapidly simulating the states of the watershed at high resolution, and 4) signal processing tools for data mining and parameter estimation. The prototype proposed sensor array and simulation system proposed is demonstrated with preliminary results from our first year.

  1. Entanglement of two qubits coupled to an XY spin chain: Role of energy current

    NASA Astrophysics Data System (ADS)

    Liu, Ben-Qiong; Shao, Bin; Zou, Jian

    2009-12-01

    We investigate the entanglement dynamics of a two-qubit system which interacts with a Heisenberg XY spin chain constrained to carry an energy current. We show an explicit connection between the decoherence factor and entanglement, and numerically and analytically study the dynamical process of entanglement in both weak- and strong-coupling cases for two initial states, the general pure state and the mixed Werner state. We provide results that the entanglement evolution depends not only on the energy current, the anisotropy parameter and the system-environment couplings but also on the size of degrees of freedom of environment. In particular, our results imply that entanglement will be strongly suppressed by the introduction of energy current on the environmental spin chain in the weak-coupling region while it is not sensitive to the energy current in the strong-coupling region. We also observe the sudden death of entanglement in the system and show how the energy current affects the phenomenon.

  2. A metalloenzyme-like catalytic system for the chemoselective oxidative cross-coupling of primary amines to imines under ambient conditions.

    PubMed

    Largeron, Martine; Fleury, Maurice-Bernard

    2015-02-23

    The direct oxidative cross-coupling of primary amines is a challenging transformation as homocoupling is usually preferred. We report herein the chemoselective preparation of cross-coupled imines through the synergistic combination of low loadings of Cu(II) metal-catalyst and o-iminoquinone organocatalyst under ambient conditions. This homogeneous cooperative catalytic system has been inspired by the reaction of copper amine oxidases, a family of metalloenzymes with quinone organic cofactors that mediate the selective oxidation of primary amines to aldehydes. After optimization, the desired cross-coupled imines are obtained in high yields with broad substrate scope through a transamination process that leads to the homocoupled imine intermediate, followed by dynamic transimination. The ability to carry out the reactions at room temperature and with ambient air, rather than molecular oxygen as the oxidant, and equimolar amounts of each coupling partner is particularly attractive from an environmentally viewpoint. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. The Modular Modeling System (MMS): A toolbox for water- and environmental-resources management

    USGS Publications Warehouse

    Leavesley, G.H.; Markstrom, S.L.; Viger, R.J.; Hay, L.E.; ,

    2005-01-01

    The increasing complexity of water- and environmental-resource problems require modeling approaches that incorporate knowledge from a broad range of scientific and software disciplines. To address this need, the U.S. Geological Survey (USGS) has developed the Modular Modeling System (MMS). MMS is an integrated system of computer software for model development, integration, and application. Its modular design allows a high level of flexibility and adaptability to enable modelers to incorporate their own software into a rich array of built-in models and modeling tools. These include individual process models, tightly coupled models, loosely coupled models, and fully- integrated decision support systems. A geographic information system (GIS) interface, the USGS GIS Weasel, has been integrated with MMS to enable spatial delineation and characterization of basin and ecosystem features, and to provide objective parameter-estimation methods for models using available digital data. MMS provides optimization and sensitivity-analysis tools to analyze model parameters and evaluate the extent to which uncertainty in model parameters affects uncertainty in simulation results. MMS has been coupled with the Bureau of Reclamation object-oriented reservoir and river-system modeling framework, RiverWare, to develop models to evaluate and apply optimal resource-allocation and management strategies to complex, operational decisions on multipurpose reservoir systems and watersheds. This decision support system approach has been developed, tested, and implemented in the Gunnison, Yakima, San Joaquin, Rio Grande, and Truckee River basins of the western United States. MMS is currently being coupled with the U.S. Forest Service model SIMulating Patterns and Processes at Landscape Scales (SIMPPLLE) to assess the effects of alternative vegetation-management strategies on a variety of hydrological and ecological responses. Initial development and testing of the MMS-SIMPPLLE integration is being conducted on the Colorado Plateau region of the western United Sates.

  4. Mercury removal from water streams through the ion exchange membrane bioreactor concept.

    PubMed

    Oehmen, Adrian; Vergel, Dario; Fradinho, Joana; Reis, Maria A M; Crespo, João G; Velizarov, Svetlozar

    2014-01-15

    Mercury is a highly toxic heavy metal that causes human health problems and environmental contamination. In this study, an ion exchange membrane bioreactor (IEMB) process was developed to achieve Hg(II) removal from drinking water and industrial effluents. Hg(II) transport through a cation exchange membrane was coupled with its bioreduction to Hg(0) in order to achieve Hg removal from concentrated streams, with minimal production of contaminated by-products observed. This study involves (1) membrane selection, (2) demonstration of process effectiveness for removing Hg from drinking water to below the 1ppb recommended limit, and (3) process application for treatment of concentrated water streams, where >98% of the Hg was removed, and the throughput of contaminated water was optimised through membrane pre-treatment. The IEMB process represents a novel mercury treatment technology with minimal generation of contaminated waste, thereby reducing the overall environmental impact of the process. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Real-time monitoring of immune responses under pathogen invasion and drug interference by integrated microfluidic device coupled with worm-based biosensor.

    PubMed

    Hu, Liang; Ge, Anle; Wang, Xixian; Wang, Shanshan; Yue, Xinpei; Wang, Jie; Feng, Xiaojun; Du, Wei; Liu, Bi-Feng

    2018-07-01

    Immune response to environmental pathogen invasion is a complex process to prevent host from further damage. For quantitatively understanding immune responses and revealing the pathogenic environmental information, real-time monitoring of such a whole dynamic process with single-animal resolution in well-defined environments is highly desired. In this work, an integrated microfluidic device coupled with worm-based biosensor was proposed for in vivo studies of dynamic immune responses and antibiotics interference in infected C. elegans. Individual worms housed in chambers were exposed to the various pathogens and discontinuously manipulated for imaging with limited influence on physiological activities. The expression of immune responses gene (irg-1) was time-lapse measured in intact worms during pathogen infection. Results demonstrated that irg-1 gene could be induced in the presence of P. aeruginosa strain PA14 in a dose-dependent manner, and the survival of infected worm could be rescued under gentamicin or erythromycin treatments. We expect it to be a versatile platform to facilitate future studies on pathogenesis researches and rapid drug screen using C. elegans disease model. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Fully coupled approach to modeling shallow water flow, sediment transport, and bed evolution in rivers

    NASA Astrophysics Data System (ADS)

    Li, Shuangcai; Duffy, Christopher J.

    2011-03-01

    Our ability to predict complex environmental fluid flow and transport hinges on accurate and efficient simulations of multiple physical phenomenon operating simultaneously over a wide range of spatial and temporal scales, including overbank floods, coastal storm surge events, drying and wetting bed conditions, and simultaneous bed form evolution. This research implements a fully coupled strategy for solving shallow water hydrodynamics, sediment transport, and morphological bed evolution in rivers and floodplains (PIHM_Hydro) and applies the model to field and laboratory experiments that cover a wide range of spatial and temporal scales. The model uses a standard upwind finite volume method and Roe's approximate Riemann solver for unstructured grids. A multidimensional linear reconstruction and slope limiter are implemented, achieving second-order spatial accuracy. Model efficiency and stability are treated using an explicit-implicit method for temporal discretization with operator splitting. Laboratory-and field-scale experiments were compiled where coupled processes across a range of scales were observed and where higher-order spatial and temporal accuracy might be needed for accurate and efficient solutions. These experiments demonstrate the ability of the fully coupled strategy in capturing dynamics of field-scale flood waves and small-scale drying-wetting processes.

  7. A GIS-based decision support system for regional eco-security assessment and its application on the Tibetan Plateau.

    PubMed

    Xiaodan, Wang; Xianghao, Zhong; Pan, Gao

    2010-10-01

    Regional eco-security assessment is an intricate, challenging task. In previous studies, the integration of eco-environmental models and geographical information systems (GIS) usually takes two approaches: loose coupling and tight coupling. However, the present study used a full coupling approach to develop a GIS-based regional eco-security assessment decision support system (ESDSS). This was achieved by merging the pressure-state-response (PSR) model and the analytic hierarchy process (AHP) into ArcGIS 9 as a dynamic link library (DLL) using ArcObjects in ArcGIS and Visual Basic for Applications. Such an approach makes it easy to capitalize on the GIS visualization and spatial analysis functions, thereby significantly supporting the dynamic estimation of regional eco-security. A case study is presented for the Tibetan Plateau, known as the world's "third pole" after the Arctic and Antarctic. Results verified the usefulness and feasibility of the developed method. As a useful tool, the ESDSS can also help local managers to make scientifically-based and effective decisions about Tibetan eco-environmental protection and land use. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  8. BIOLEACH: Coupled modeling of leachate and biogas production on solid waste landfills

    NASA Astrophysics Data System (ADS)

    Rodrigo-Clavero, Maria-Elena; Rodrigo-Ilarri, Javier

    2015-04-01

    One of the most important factors to address when performing the environmental impact assessment of urban solid waste landfills is to evaluate the leachate production. Leachate management (collection and treatment) is also one of the most relevant economical aspects to take into account during the landfill life. Leachate is formed as a solution of biological and chemical components during operational and post-operational phases on urban solid waste landfills as a combination of different processes that involve water gains and looses inside the solid waste mass. Infiltration of external water coming from precipitation is the most important component on this water balance. However, anaerobic waste decomposition and biogas formation processes play also a role on the balance as water-consuming processes. The production of leachate one biogas is therefore a coupled process. Biogas production models usually consider optimal conditions of water content on the solid waste mass. However, real conditions during the operational phase of the landfill may greatly differ from these optimal conditions. In this work, the first results obtained to predict both the leachate and the biogas production as a single coupled phenomenon on real solid waste landfills are shown. The model is applied on a synthetic case considering typical climatological conditions of Mediterranean catchments.

  9. A MODELING AND SIMULATION LANGUAGE FOR BIOLOGICAL CELLS WITH COUPLED MECHANICAL AND CHEMICAL PROCESSES

    PubMed Central

    Somogyi, Endre; Glazier, James A.

    2017-01-01

    Biological cells are the prototypical example of active matter. Cells sense and respond to mechanical, chemical and electrical environmental stimuli with a range of behaviors, including dynamic changes in morphology and mechanical properties, chemical uptake and secretion, cell differentiation, proliferation, death, and migration. Modeling and simulation of such dynamic phenomena poses a number of computational challenges. A modeling language describing cellular dynamics must naturally represent complex intra and extra-cellular spatial structures and coupled mechanical, chemical and electrical processes. Domain experts will find a modeling language most useful when it is based on concepts, terms and principles native to the problem domain. A compiler must then be able to generate an executable model from this physically motivated description. Finally, an executable model must efficiently calculate the time evolution of such dynamic and inhomogeneous phenomena. We present a spatial hybrid systems modeling language, compiler and mesh-free Lagrangian based simulation engine which will enable domain experts to define models using natural, biologically motivated constructs and to simulate time evolution of coupled cellular, mechanical and chemical processes acting on a time varying number of cells and their environment. PMID:29303160

  10. A MODELING AND SIMULATION LANGUAGE FOR BIOLOGICAL CELLS WITH COUPLED MECHANICAL AND CHEMICAL PROCESSES.

    PubMed

    Somogyi, Endre; Glazier, James A

    2017-04-01

    Biological cells are the prototypical example of active matter. Cells sense and respond to mechanical, chemical and electrical environmental stimuli with a range of behaviors, including dynamic changes in morphology and mechanical properties, chemical uptake and secretion, cell differentiation, proliferation, death, and migration. Modeling and simulation of such dynamic phenomena poses a number of computational challenges. A modeling language describing cellular dynamics must naturally represent complex intra and extra-cellular spatial structures and coupled mechanical, chemical and electrical processes. Domain experts will find a modeling language most useful when it is based on concepts, terms and principles native to the problem domain. A compiler must then be able to generate an executable model from this physically motivated description. Finally, an executable model must efficiently calculate the time evolution of such dynamic and inhomogeneous phenomena. We present a spatial hybrid systems modeling language, compiler and mesh-free Lagrangian based simulation engine which will enable domain experts to define models using natural, biologically motivated constructs and to simulate time evolution of coupled cellular, mechanical and chemical processes acting on a time varying number of cells and their environment.

  11. Modeling Time-Dependent Behavior of Concrete Affected by Alkali Silica Reaction in Variable Environmental Conditions.

    PubMed

    Alnaggar, Mohammed; Di Luzio, Giovanni; Cusatis, Gianluca

    2017-04-28

    Alkali Silica Reaction (ASR) is known to be a serious problem for concrete worldwide, especially in high humidity and high temperature regions. ASR is a slow process that develops over years to decades and it is influenced by changes in environmental and loading conditions of the structure. The problem becomes even more complicated if one recognizes that other phenomena like creep and shrinkage are coupled with ASR. This results in synergistic mechanisms that can not be easily understood without a comprehensive computational model. In this paper, coupling between creep, shrinkage and ASR is modeled within the Lattice Discrete Particle Model (LDPM) framework. In order to achieve this, a multi-physics formulation is used to compute the evolution of temperature, humidity, cement hydration, and ASR in both space and time, which is then used within physics-based formulations of cracking, creep and shrinkage. The overall model is calibrated and validated on the basis of experimental data available in the literature. Results show that even during free expansions (zero macroscopic stress), a significant degree of coupling exists because ASR induced expansions are relaxed by meso-scale creep driven by self-equilibriated stresses at the meso-scale. This explains and highlights the importance of considering ASR and other time dependent aging and deterioration phenomena at an appropriate length scale in coupled modeling approaches.

  12. THE EARTH SYSTEM PREDICTION SUITE: Toward a Coordinated U.S. Modeling Capability

    PubMed Central

    Theurich, Gerhard; DeLuca, C.; Campbell, T.; Liu, F.; Saint, K.; Vertenstein, M.; Chen, J.; Oehmke, R.; Doyle, J.; Whitcomb, T.; Wallcraft, A.; Iredell, M.; Black, T.; da Silva, AM; Clune, T.; Ferraro, R.; Li, P.; Kelley, M.; Aleinov, I.; Balaji, V.; Zadeh, N.; Jacob, R.; Kirtman, B.; Giraldo, F.; McCarren, D.; Sandgathe, S.; Peckham, S.; Dunlap, R.

    2017-01-01

    The Earth System Prediction Suite (ESPS) is a collection of flagship U.S. weather and climate models and model components that are being instrumented to conform to interoperability conventions, documented to follow metadata standards, and made available either under open source terms or to credentialed users. The ESPS represents a culmination of efforts to create a common Earth system model architecture, and the advent of increasingly coordinated model development activities in the U.S. ESPS component interfaces are based on the Earth System Modeling Framework (ESMF), community-developed software for building and coupling models, and the National Unified Operational Prediction Capability (NUOPC) Layer, a set of ESMF-based component templates and interoperability conventions. This shared infrastructure simplifies the process of model coupling by guaranteeing that components conform to a set of technical and semantic behaviors. The ESPS encourages distributed, multi-agency development of coupled modeling systems, controlled experimentation and testing, and exploration of novel model configurations, such as those motivated by research involving managed and interactive ensembles. ESPS codes include the Navy Global Environmental Model (NavGEM), HYbrid Coordinate Ocean Model (HYCOM), and Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS®); the NOAA Environmental Modeling System (NEMS) and the Modular Ocean Model (MOM); the Community Earth System Model (CESM); and the NASA ModelE climate model and GEOS-5 atmospheric general circulation model. PMID:29568125

  13. Modeling Time-Dependent Behavior of Concrete Affected by Alkali Silica Reaction in Variable Environmental Conditions

    PubMed Central

    Alnaggar, Mohammed; Di Luzio, Giovanni; Cusatis, Gianluca

    2017-01-01

    Alkali Silica Reaction (ASR) is known to be a serious problem for concrete worldwide, especially in high humidity and high temperature regions. ASR is a slow process that develops over years to decades and it is influenced by changes in environmental and loading conditions of the structure. The problem becomes even more complicated if one recognizes that other phenomena like creep and shrinkage are coupled with ASR. This results in synergistic mechanisms that can not be easily understood without a comprehensive computational model. In this paper, coupling between creep, shrinkage and ASR is modeled within the Lattice Discrete Particle Model (LDPM) framework. In order to achieve this, a multi-physics formulation is used to compute the evolution of temperature, humidity, cement hydration, and ASR in both space and time, which is then used within physics-based formulations of cracking, creep and shrinkage. The overall model is calibrated and validated on the basis of experimental data available in the literature. Results show that even during free expansions (zero macroscopic stress), a significant degree of coupling exists because ASR induced expansions are relaxed by meso-scale creep driven by self-equilibriated stresses at the meso-scale. This explains and highlights the importance of considering ASR and other time dependent aging and deterioration phenomena at an appropriate length scale in coupled modeling approaches. PMID:28772829

  14. THE EARTH SYSTEM PREDICTION SUITE: Toward a Coordinated U.S. Modeling Capability.

    PubMed

    Theurich, Gerhard; DeLuca, C; Campbell, T; Liu, F; Saint, K; Vertenstein, M; Chen, J; Oehmke, R; Doyle, J; Whitcomb, T; Wallcraft, A; Iredell, M; Black, T; da Silva, A M; Clune, T; Ferraro, R; Li, P; Kelley, M; Aleinov, I; Balaji, V; Zadeh, N; Jacob, R; Kirtman, B; Giraldo, F; McCarren, D; Sandgathe, S; Peckham, S; Dunlap, R

    2016-07-01

    The Earth System Prediction Suite (ESPS) is a collection of flagship U.S. weather and climate models and model components that are being instrumented to conform to interoperability conventions, documented to follow metadata standards, and made available either under open source terms or to credentialed users. The ESPS represents a culmination of efforts to create a common Earth system model architecture, and the advent of increasingly coordinated model development activities in the U.S. ESPS component interfaces are based on the Earth System Modeling Framework (ESMF), community-developed software for building and coupling models, and the National Unified Operational Prediction Capability (NUOPC) Layer, a set of ESMF-based component templates and interoperability conventions. This shared infrastructure simplifies the process of model coupling by guaranteeing that components conform to a set of technical and semantic behaviors. The ESPS encourages distributed, multi-agency development of coupled modeling systems, controlled experimentation and testing, and exploration of novel model configurations, such as those motivated by research involving managed and interactive ensembles. ESPS codes include the Navy Global Environmental Model (NavGEM), HYbrid Coordinate Ocean Model (HYCOM), and Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS ® ); the NOAA Environmental Modeling System (NEMS) and the Modular Ocean Model (MOM); the Community Earth System Model (CESM); and the NASA ModelE climate model and GEOS-5 atmospheric general circulation model.

  15. The Earth System Prediction Suite: Toward a Coordinated U.S. Modeling Capability

    NASA Technical Reports Server (NTRS)

    Theurich, Gerhard; DeLuca, C.; Campbell, T.; Liu, F.; Saint, K.; Vertenstein, M.; Chen, J.; Oehmke, R.; Doyle, J.; Whitcomb, T.; hide

    2016-01-01

    The Earth System Prediction Suite (ESPS) is a collection of flagship U.S. weather and climate models and model components that are being instrumented to conform to interoperability conventions, documented to follow metadata standards, and made available either under open source terms or to credentialed users.The ESPS represents a culmination of efforts to create a common Earth system model architecture, and the advent of increasingly coordinated model development activities in the U.S. ESPS component interfaces are based on the Earth System Modeling Framework (ESMF), community-developed software for building and coupling models, and the National Unified Operational Prediction Capability (NUOPC) Layer, a set of ESMF-based component templates and interoperability conventions. This shared infrastructure simplifies the process of model coupling by guaranteeing that components conform to a set of technical and semantic behaviors. The ESPS encourages distributed, multi-agency development of coupled modeling systems, controlled experimentation and testing, and exploration of novel model configurations, such as those motivated by research involving managed and interactive ensembles. ESPS codes include the Navy Global Environmental Model (NavGEM), HYbrid Coordinate Ocean Model (HYCOM), and Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS); the NOAA Environmental Modeling System (NEMS) and the Modular Ocean Model (MOM); the Community Earth System Model (CESM); and the NASA ModelE climate model and GEOS-5 atmospheric general circulation model.

  16. Coupling of methylmercury uptake with respiration and water pumping in freshwater tilapia Oreochromis niloticus.

    PubMed

    Wang, Rui; Wong, Ming-Hung; Wang, Wen-Xiong

    2011-09-01

    The relationships among the uptake of toxic methylmercury (MeHg) and two important fish physiological processes-respiration and water pumping--in the Nile tilapia (Oreochromis niloticus) were explored in the present study. Coupled radiotracer and respirometric techniques were applied to measure simultaneously the uptake rates of MeHg, water, and oxygen under various environmental conditions (temperature, dissolved oxygen level, and water flow). A higher temperature enhanced MeHg influx and the oxygen consumption rate but had no effect on the water uptake, indicating the influence of metabolism on MeHg uptake. The fish showed a high tolerance to hypoxia, and the oxygen consumption rate was not affected until the dissolved oxygen concentration decreased to extremely low levels (below 1 mg/L). The MeHg and water uptake rates increased simultaneously as the dissolved oxygen level decreased, suggesting the coupling of water flux and MeHg uptake. The influence of fish swimming performance on MeHg uptake was also investigated for the first time. Rapidly swimming fish showed significantly higher uptake rates of MeHg, water, and oxygen, confirming the coupling relationships among respiration, water pumping, and metal uptake. Moreover, these results support that MeHg uptake is a rate-limiting process involving energy. Our study demonstrates the importance of physiological processes in understanding mercury bioaccumulation in fluctuating aquatic environments. Copyright © 2011 SETAC.

  17. Delivering better power: the role of simulation in reducing the environmental impact of aircraft engines.

    PubMed

    Menzies, Kevin

    2014-08-13

    The growth in simulation capability over the past 20 years has led to remarkable changes in the design process for gas turbines. The availability of relatively cheap computational power coupled to improvements in numerical methods and physical modelling in simulation codes have enabled the development of aircraft propulsion systems that are more powerful and yet more efficient than ever before. However, the design challenges are correspondingly greater, especially to reduce environmental impact. The simulation requirements to achieve a reduced environmental impact are described along with the implications of continued growth in available computational power. It is concluded that achieving the environmental goals will demand large-scale multi-disciplinary simulations requiring significantly increased computational power, to enable optimization of the airframe and propulsion system over the entire operational envelope. However even with massive parallelization, the limits imposed by communications latency will constrain the time required to achieve a solution, and therefore the position of such large-scale calculations in the industrial design process. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  18. Understanding the relation between urbanization and the eco-environment in China's Yangtze River Delta using an improved EKC model and coupling analysis.

    PubMed

    Zhao, Yabo; Wang, Shaojian; Zhou, Chunshan

    2016-11-15

    Better understanding the relationship between urbanization (U) and the eco-environment (E) is necessary to coordinate the development of them. Using a comprehensive index system for U and E with statistic data, and an improved environmental Kuznets curve (EKC) model and dynamic coordination coupling degree (CCD) model, this study addressed the relationship between U and E in the Yangtze River Delta (YRD) in the period 1980-2013. The main conclusions were as follows: (1) Economic urbanization and eco-environment endowment were the highest weighted factors in the U and E system respectively, and thus constitute the key factors. (2) Differentiated inverted-U curves were shown to exist in the relation between U and E across the cities studied, thereby confirming the improved EKC hypothesis. We further found economically developed areas to have higher urbanization levels than less developed areas at the point at which the curve inflects, less developed areas have higher eco-environmental pressure at inflection. Before the appearance of the inflection point, a striking positive correlation was observed between eco-environmental pressure and the urbanization level, while a negative correlation was found to follow it. (3) A dynamic coordination coupling relation was found to exist between U and E, which conforms to an S-shaped curve. The coordination coupling process in the YRD has gradually moved from a "low-grade symbiosis" stage into a "break-in development" stage, but the pattern of coordination belonging to the eco-environment part of the relation was found to always show some lag. The dynamic CCD model showed a difference in the spatial distribution of CCD, presenting higher values in the periphery of the region, and lower values in the center during the study period. The improved EKC and coupling analysis detailed in this study may help Chinese decision makers to formulate sustainable measures to balance urbanization development and eco-environment protection. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Environmental sustainability assessment of hydropower plant in Europe using life cycle assessment

    NASA Astrophysics Data System (ADS)

    Mahmud, M. A. P.; Huda, N.; Farjana, S. H.; Lang, C.

    2018-05-01

    Hydropower is the oldest and most common type of renewable source of electricity available on this planet. The end of life process of hydropower plant have significant environmental impacts, which needs to be identified and minimized to ensure an environment friendly power generation. However, identifying the environmental impacts and health hazards are very little explored in the hydropower processing routes despite a significant quantity of production worldwide. This paper highlight the life-cycle environmental impact assessment of the reservoir based hydropower generation system located in alpine and non-alpine region of Europe, addressing their ecological effects by the ReCiPe and CML methods under several impact-assessment categories such as human health, ecosystems, global warming potential, acidification potential, etc. The Australasian life-cycle inventory database and SimaPro software are utilized to accumulate life-cycle inventory dataset and to evaluate the impacts. The results reveal that plants of alpine region offer superior environmental performance for couple of considered categories: global warming and photochemical oxidation, whilst in the other cases the outcomes are almost similar. Results obtained from this study will take part an important role in promoting sustainable generation of hydropower, and thus towards environment friendly energy production.

  20. How noise and coupling influence leading indicators of population extinction in a spatially extended ecological system.

    PubMed

    O'Regan, Suzanne M

    2018-12-01

    Anticipating critical transitions in spatially extended systems is a key topic of interest to ecologists. Gradually declining metapopulations are an important example of a spatially extended biological system that may exhibit a critical transition. Theory for spatially extended systems approaching extinction that accounts for environmental stochasticity and coupling is currently lacking. Here, we develop spatially implicit two-patch models with additive and multiplicative forms of environmental stochasticity that are slowly forced through population collapse, through changing environmental conditions. We derive patch-specific expressions for candidate indicators of extinction and test their performance via a simulation study. Coupling and spatial heterogeneities decrease the magnitude of the proposed indicators in coupled populations relative to isolated populations, and the noise regime and the degree of coupling together determine trends in summary statistics. This theory may be readily applied to other spatially extended ecological systems, such as coupled infectious disease systems on the verge of elimination.

  1. Energy Harvesting with Coupled Magnetorestrictive Resonators

    DTIC Science & Technology

    2013-09-01

    matching, small hysteresis, and low coercivity2. Ceramic material like PZT tends to develop fatigue during its cycles whereas Galfenol does not have...Magnetostrictive Material PZT Pb [ZrxTi1-x] O3, 0<xə, Lead Zirconate Titanate RX Receiver SHM Structural Health Monitoring...zirconate titanate [ PZT ]) have lead in their fabrication process, which is an environmental risk. Another major issue with standard energy

  2. Improving the feasibility of producing biofuels from microalgae using wastewater.

    PubMed

    Rawat, I; Bhola, V; Kumar, R Ranjith; Bux, F

    2013-01-01

    Biofuels have received much attention recently owing to energy consumption and environmental concerns. Despite many of the technologies being technically feasible, the processes are often too costly to be commercially viable. The major stumbling block to full-scale production of algal biofuels is the cost of upstream and downstream processes and environmental impacts such as water footprint and indirect greenhouse gas emissions from chemical nutrient production. The technoeconomics of biofuels production from microalgae is currently unfeasible due to the cost of inputs and productivities achieved. The use of a biorefinery approach sees the production costs reduced greatly due to utilization of waste streams for cultivation and the generation of several potential energy sources and value-added products while offering environmental protection. The use of wastewater as a production media, coupled with CO2 sequestration from flue gas greatly reduces the microalgal cultivation costs. Conversion of residual biomass and by-products, such as glycerol, for fuel production using an integrated approach potentially holds the key to near future commercial implementation of biofuels production.

  3. Report for Oregon State University Reporting Period: June 2016 to June 2017

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hutchings, Jennifer

    The goal of this project is to develop an eddy resolving ocean model (POP) with tides coupled to a sea ice model (CICE) within the Regional Arctic System Model (RASM) to investigate the importance of ocean tides and mesoscale eddies in arctic climate simulations and quantify biases associated with these processes and how their relative contribution may improve decadal to centennial arctic climate predictions. Ocean, sea ice and coupled arctic climate response to these small scale processes will be evaluated with regard to their influence on mass, momentum and property exchange between oceans, shelf-basin, ice-ocean, and ocean-atmosphere. The project willmore » facilitate the future routine inclusion of polar tides and eddies in Earth System Models when computing power allows. As such, the proposed research addresses the science in support of the BER’s Climate and Environmental Sciences Division Long Term Measure as it will improve the ocean and sea ice model components as well as the fully coupled RASM and Community Earth System Model (CESM) and it will make them more accurate and computationally efficient.« less

  4. Developing a novel UAV (Unmanned Aerial Vehicle) helicopter platform for very high resolution environmental monitoring of catchment processes

    NASA Astrophysics Data System (ADS)

    Freer, J. E.; Richardson, T.; Yang, Z.

    2012-12-01

    Recent advances in remote sensing and geographic information has led the way for the development of hyperspectral sensors and cloud scanning LIDAR (Light Detection And Ranging). Both these technologies can be used to sense environmental processes and capture detailed spatial information, they are often deployed in ground, aircraft and satellite based systems. Hyperspectral remote sensing, also known as imaging spectroscopy, is a relatively new technology that is currently being investigated by researchers and scientists with regard to the detection and identification of landscapes, terrestrial vegetation, and manmade materials and backgrounds. There are many applications that could take advantages of hyperspectral remote sensing coupled to detailed surface feature mapping using LIDAR. This embryonic project involves developing the engineering solutions and post processing techniques needed to realise an ultra high resolution helicopter based environmental sensing platform which can fly at lower altitudes than aircraft systems and can be deployed more frequently. We aim to present this new technology platform in this special session (the only one of it's kind in the UK). Initial applications are planned on a range of environmental sensing problems that would benefit from such complex and detailed data.We look forward to being able to display and discuss this initiative with colleagues and any potential interest in future collaborative projects.

  5. Developing a novel UAV (Unmanned Aerial Vehicle) helicopter platform for very high resolution environmental monitoring of catchment processes

    NASA Astrophysics Data System (ADS)

    Freer, J.; Richardson, T. S.

    2012-04-01

    Recent advances in remote sensing and geographic information has led the way for the development of hyperspectral sensors and cloud scanning LIDAR (Light Detection And Ranging). Both these technologies can be used to sense environmental processes and capture detailed spatial information, they are often deployed in ground, aircraft and satellite based systems. Hyperspectral remote sensing, also known as imaging spectroscopy, is a relatively new technology that is currently being investigated by researchers and scientists with regard to the detection and identification of landscapes, terrestrial vegetation, and manmade materials and backgrounds. There are many applications that could take advantages of hyperspectral remote sensing coupled to detailed surface feature mapping using LIDAR. This embryonic project involves developing the engineering solutions and post processing techniques needed to realise an ultra high resolution helicopter based environmental sensing platform which can fly at lower altitudes than aircraft systems and can be deployed more frequently. We aim to display this new technology platform in this special session (the only one of it's kind in the UK). Initial applications are planned on a range of environmental sensing problems that would benefit from such complex and detailed data. We look forward to being able to display and discuss this initiative with colleagues and any potential interest in future collaborative projects.

  6. High-brightness line generators and fiber-coupled sources based on low-smile laser diode arrays

    NASA Astrophysics Data System (ADS)

    Watson, J.; Schleuning, D.; Lavikko, P.; Alander, T.; Lee, D.; Lovato, P.; Winhold, H.; Griffin, M.; Tolman, S.; Liang, P.; Hasenberg, T.; Reed, M.

    2008-02-01

    We describe the performance of diode laser bars mounted on conductive and water cooled platforms using low smile processes. Total smile of <1μm is readily achieved on both In and AuSn based platforms. Combined with environmentally robust lensing, these mounts form the basis of multiple, high-brightness products. Free-space-coupled devices utilizing conductively-cooled bars delivering 100W from a 200μm, 0.22NA fiber at 976nm have been developed for pumping fiber lasers, as well as for materials processing. Additionally, line generators for graphics and materials processing applications have been produced. Starting from single bars mounted on water-cooled packages that do not require de-ionized or pH-controlled water, these line generators deliver over 80W of power into a line with an aspect ratio of 600:1, and have a BPP of <2mm-mrad in the direction orthogonal to the line.

  7. DETERMINATION OF CHLOROETHENES IN ENVIRONMENTAL BIOLOGICAL SAMPLES USING GAS CHROMATOGRAPHY COUPLED WITH SOLID PHASE MICRO EXTRACTION

    EPA Science Inventory

    An analytical method has been developed to determine the chloroethene series, tetrachloroethene (PCE), trichloroethene (TCE),cisdichloroethene (cis-DCE) andtransdichloroethene (trans-DCE) in environmental biotreatment studies using gas chromatography coupled with a solid phase mi...

  8. Ecosystem effects of environmental flows: Modelling and experimental floods in a dryland river

    USGS Publications Warehouse

    Shafroth, P.B.; Wilcox, A.C.; Lytle, D.A.; Hickey, J.T.; Andersen, D.C.; Beauchamp, Vanessa B.; Hautzinger, A.; McMullen, L.E.; Warner, A.

    2010-01-01

    Successful environmental flow prescriptions require an accurate understanding of the linkages among flow events, geomorphic processes and biotic responses. We describe models and results from experimental flow releases associated with an environmental flow program on the Bill Williams River (BWR), Arizona, in arid to semiarid western U.S.A. Two general approaches for improving knowledge and predictions of ecological responses to environmental flows are: (1) coupling physical system models to ecological responses and (2) clarifying empirical relationships between flow and ecological responses through implementation and monitoring of experimental flow releases. We modelled the BWR physical system using: (1) a reservoir operations model to simulate reservoir releases and reservoir water levels and estimate flow through the river system under a range of scenarios, (2) one- and two-dimensional river hydraulics models to estimate stage-discharge relationships at the whole-river and local scales, respectively, and (3) a groundwater model to estimate surface- and groundwater interactions in a large, alluvial valley on the BWR where surface flow is frequently absent. An example of a coupled, hydrology-ecology model is the Ecosystems Function Model, which we used to link a one-dimensional hydraulic model with riparian tree seedling establishment requirements to produce spatially explicit predictions of seedling recruitment locations in a Geographic Information System. We also quantified the effects of small experimental floods on the differential mortality of native and exotic riparian trees, on beaver dam integrity and distribution, and on the dynamics of differentially flow-adapted benthic macroinvertebrate groups. Results of model applications and experimental flow releases are contributing to adaptive flow management on the BWR and to the development of regional environmental flow standards. General themes that emerged from our work include the importance of response thresholds, which are commonly driven by geomorphic thresholds or mediated by geomorphic processes, and the importance of spatial and temporal variation in the effects of flows on ecosystems, which can result from factors such as longitudinal complexity and ecohydrological feedbacks. ?? Published 2009.

  9. Improved simulation of tropospheric ozone by a global-multi-regional two-way coupling model system

    NASA Astrophysics Data System (ADS)

    Yan, Yingying; Lin, Jintai; Chen, Jinxuan; Hu, Lu

    2016-02-01

    Small-scale nonlinear chemical and physical processes over pollution source regions affect the tropospheric ozone (O3), but these processes are not captured by current global chemical transport models (CTMs) and chemistry-climate models that are limited by coarse horizontal resolutions (100-500 km, typically 200 km). These models tend to contain large (and mostly positive) tropospheric O3 biases in the Northern Hemisphere. Here we use the recently built two-way coupling system of the GEOS-Chem CTM to simulate the regional and global tropospheric O3 in 2009. The system couples the global model (at 2.5° long. × 2° lat.) and its three nested models (at 0.667° long. × 0.5° lat.) covering Asia, North America and Europe, respectively. Specifically, the nested models take lateral boundary conditions (LBCs) from the global model, better capture small-scale processes and feed back to modify the global model simulation within the nested domains, with a subsequent effect on their LBCs. Compared to the global model alone, the two-way coupled system better simulates the tropospheric O3 both within and outside the nested domains, as found by evaluation against a suite of ground (1420 sites from the World Data Centre for Greenhouse Gases (WDCGG), the United States National Oceanic and Atmospheric Administration (NOAA) Earth System Research Laboratory Global Monitoring Division (GMD), the Chemical Coordination Centre of European Monitoring and Evaluation Programme (EMEP), and the United States Environmental Protection Agency Air Quality System (AQS)), aircraft (the High-performance Instrumented Airborne Platform for Environmental Research (HIAPER) Pole-to-Pole Observations (HIPPO) and Measurement of Ozone and Water Vapor by Airbus In- Service Aircraft (MOZAIC)) and satellite measurements (two Ozone Monitoring Instrument (OMI) products). The two-way coupled simulation enhances the correlation in day-to-day variation of afternoon mean surface O3 with the ground measurements from 0.53 to 0.68, and it reduces the mean model bias from 10.8 to 6.7 ppb. Regionally, the coupled system reduces the bias by 4.6 ppb over Europe, 3.9 ppb over North America and 3.1 ppb over other regions. The two-way coupling brings O3 vertical profiles much closer to the HIPPO (for remote areas) and MOZAIC (for polluted regions) data, reducing the tropospheric (0-9 km) mean bias by 3-10 ppb at most MOZAIC sites and by 5.3 ppb for HIPPO profiles. The two-way coupled simulation also reduces the global tropospheric column ozone by 3.0 DU (9.5 %, annual mean), bringing them closer to the OMI data in all seasons. Additionally, the two-way coupled simulation also reduces the global tropospheric mean hydroxyl radical by 5 % with improved estimates of methyl chloroform and methane lifetimes. Simulation improvements are more significant in the Northern Hemisphere, and are mainly driven by improved representation of spatial inhomogeneity in chemistry/emissions. Within the nested domains, the two-way coupled simulation reduces surface ozone biases relative to typical GEOS-Chem one-way nested simulations, due to much improved LBCs. The bias reduction is 1-7 times the bias reduction from the global to the one-way nested simulation. Improving model representations of small-scale processes is important for understanding the global and regional tropospheric chemistry.

  10. Dynamical Models for Sloshing Dynamics of Helium 2 Under Low-G Conditions

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Long, Y. T.

    1997-01-01

    Coupling of sloshing dynamics within a partially filled rotating dewar of superfluid helium 2 with spacecraft dynamics are investigated in response to the realistic environmental disturbance forces and torques acting on the spacecraft during normal operation. This study investigates: (1) the rotating bubble of superfluid helium 2 reacting to combined environmental disturbances, including gravity gradient, aerodynamic, and magnetic forces and torques; (2) characteristics of slosh reaction forces and torques coupling with spacecraft dynamics; (3) the contribution of slosh dynamics to over-all spacecraft dynamics; and (4) activating of attitude and translation control system. The numerical computation of sloshing dynamics is based on the rotational frame, while the spacecraft dynamics is associated with non-rotational frame. Results show that the contributions of spacecraft dynamics are driven by the environmental disturbances coupling with slosh dynamics. Without considering the effects of environmental disturbances-driven slosh dynamics acting on spacecraft coupling with the spacecraft dynamics may lead to the wrong results for the development of spacecraft system guidance and attitude control techniques.

  11. Patterns in Temporal Variability of Temperature, Oxygen and pH along an Environmental Gradient in a Coral Reef

    PubMed Central

    Guadayol, Òscar; Silbiger, Nyssa J.; Donahue, Megan J.; Thomas, Florence I. M.

    2014-01-01

    Spatial and temporal environmental variability are important drivers of ecological processes at all scales. As new tools allow the in situ exploration of individual responses to fluctuations, ecologically meaningful ways of characterizing environmental variability at organism scales are needed. We investigated the fine-scale spatial heterogeneity of high-frequency temporal variability in temperature, dissolved oxygen concentration, and pH experienced by benthic organisms in a shallow coastal coral reef. We used a spatio-temporal sampling design, consisting of 21 short-term time-series located along a reef flat-to-reef slope transect, coupled to a long-term station monitoring water column changes. Spectral analyses revealed sharp gradients in variance decomposed by frequency, as well as differences between physically-driven and biologically-reactive parameters. These results highlight the importance of environmental variance at organismal scales and present a new sampling scheme for exploring this variability in situ. PMID:24416364

  12. Glacial seismology.

    PubMed

    Aster, R C; Winberry, J P

    2017-12-01

    Seismic source and wave propagation studies contribute to understanding structure, transport, fracture mechanics, mass balance, and other processes within glaciers and surrounding environments. Glaciogenic seismic waves readily couple with the bulk Earth, and can be recorded by seismographs deployed at local to global ranges. Although the fracturing, ablating, melting, and/or highly irregular environment of active glaciers can be highly unstable and hazardous, informative seismic measurements can commonly be made at stable proximal ice or rock sites. Seismology also contributes more broadly to emerging studies of elastic and gravity wave coupling between the atmosphere, oceans, solid Earth, and cryosphere, and recent scientific and technical advances have produced glaciological/seismological collaborations across a broad range of scales and processes. This importantly includes improved insight into the responses of cryospheric systems to changing climate and other environmental conditions. Here, we review relevant fundamental physics and glaciology, and provide a broad review of the current state of glacial seismology and its rapidly evolving future directions.

  13. Final Report: Molecular mechanisms and kinetics of microbial anaerobic nitrate-dependent U(IV) and Fe(II) oxidation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Day, Peggy A.; Asta, Maria P.; Kanematsu, Masakazu

    2015-02-27

    In this project, we combined molecular genetic, spectroscopic, and microscopic techniques with kinetic and reactive transport studies to describe and quantify biotic and abiotic mechanisms underlying anaerobic, nitrate-dependent U(IV) and Fe(II) oxidation, which influences the long-term efficacy of in situ reductive immobilization of uranium at DOE sites. In these studies, Thiobacillus denitrificans, an autotrophic bacterium that catalyzes anaerobic U(IV) and Fe(II) oxidation, was used to examine coupled oxidation-reduction processes under either biotic (enzymatic) or abiotic conditions in batch and column experiments with biogenically produced UIVO2(s). Synthesis and quantitative analysis of coupled chemical and transport processes were done with the reactivemore » transport modeling code Crunchflow. Research focused on identifying the primary redox proteins that catalyze metal oxidation, environmental factors that influence protein expression, and molecular-scale geochemical factors that control the rates of biotic and abiotic oxidation.« less

  14. Glacial seismology

    NASA Astrophysics Data System (ADS)

    Aster, R. C.; Winberry, J. P.

    2017-12-01

    Seismic source and wave propagation studies contribute to understanding structure, transport, fracture mechanics, mass balance, and other processes within glaciers and surrounding environments. Glaciogenic seismic waves readily couple with the bulk Earth, and can be recorded by seismographs deployed at local to global ranges. Although the fracturing, ablating, melting, and/or highly irregular environment of active glaciers can be highly unstable and hazardous, informative seismic measurements can commonly be made at stable proximal ice or rock sites. Seismology also contributes more broadly to emerging studies of elastic and gravity wave coupling between the atmosphere, oceans, solid Earth, and cryosphere, and recent scientific and technical advances have produced glaciological/seismological collaborations across a broad range of scales and processes. This importantly includes improved insight into the responses of cryospheric systems to changing climate and other environmental conditions. Here, we review relevant fundamental physics and glaciology, and provide a broad review of the current state of glacial seismology and its rapidly evolving future directions.

  15. Decision Support For Digester Algae Integration For Improved Environmental And Economic Sustainability

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guillen, Donna P.; Panike, Katherine R.; Havlovick, Caryn M.

    The Idaho National Laboratory (INL) has teamed with University of Idaho and Boise State University to make the use of ADs more attractive by implementing a two-stage AD and coupling additional processes to the system. The addition of a polyhydroxyalkanoate (PHA) reactor, algae cultivation system, and a biomass treatment system such as fast-pyrolysis or hydrothermal liquefaction (HTL) would further sequester carbon and nutrients, as well as add valuable products that can be sold or used on-site to mitigate costs. The Decision-support for Digester-Algae IntegRation for Improved Environmental and Economic Sustainability (DAIRIEES) technoeconomic model will play a key role in evaluatingmore » the effectiveness and viability of this system to achieve economic and environmental sustainability by the dairy industry.« less

  16. EUREC4A: A Field Campaign to Elucidate the Couplings Between Clouds, Convection and Circulation

    NASA Astrophysics Data System (ADS)

    Bony, Sandrine; Stevens, Bjorn; Ament, Felix; Bigorre, Sebastien; Chazette, Patrick; Crewell, Susanne; Delanoë, Julien; Emanuel, Kerry; Farrell, David; Flamant, Cyrille; Gross, Silke; Hirsch, Lutz; Karstensen, Johannes; Mayer, Bernhard; Nuijens, Louise; Ruppert, James H.; Sandu, Irina; Siebesma, Pier; Speich, Sabrina; Szczap, Frédéric; Totems, Julien; Vogel, Raphaela; Wendisch, Manfred; Wirth, Martin

    2017-11-01

    Trade-wind cumuli constitute the cloud type with the highest frequency of occurrence on Earth, and it has been shown that their sensitivity to changing environmental conditions will critically influence the magnitude and pace of future global warming. Research over the last decade has pointed out the importance of the interplay between clouds, convection and circulation in controling this sensitivity. Numerical models represent this interplay in diverse ways, which translates into different responses of trade-cumuli to climate perturbations. Climate models predict that the area covered by shallow cumuli at cloud base is very sensitive to changes in environmental conditions, while process models suggest the opposite. To understand and resolve this contradiction, we propose to organize a field campaign aimed at quantifying the physical properties of trade-cumuli (e.g., cloud fraction and water content) as a function of the large-scale environment. Beyond a better understanding of clouds-circulation coupling processes, the campaign will provide a reference data set that may be used as a benchmark for advancing the modelling and the satellite remote sensing of clouds and circulation. It will also be an opportunity for complementary investigations such as evaluating model convective parameterizations or studying the role of ocean mesoscale eddies in air-sea interactions and convective organization.

  17. EUREC4A: A Field Campaign to Elucidate the Couplings Between Clouds, Convection and Circulation

    NASA Astrophysics Data System (ADS)

    Bony, Sandrine; Stevens, Bjorn; Ament, Felix; Bigorre, Sebastien; Chazette, Patrick; Crewell, Susanne; Delanoë, Julien; Emanuel, Kerry; Farrell, David; Flamant, Cyrille; Gross, Silke; Hirsch, Lutz; Karstensen, Johannes; Mayer, Bernhard; Nuijens, Louise; Ruppert, James H.; Sandu, Irina; Siebesma, Pier; Speich, Sabrina; Szczap, Frédéric; Totems, Julien; Vogel, Raphaela; Wendisch, Manfred; Wirth, Martin

    Trade-wind cumuli constitute the cloud type with the highest frequency of occurrence on Earth, and it has been shown that their sensitivity to changing environmental conditions will critically influence the magnitude and pace of future global warming. Research over the last decade has pointed out the importance of the interplay between clouds, convection and circulation in controling this sensitivity. Numerical models represent this interplay in diverse ways, which translates into different responses of tradecumuli to climate perturbations. Climate models predict that the area covered by shallow cumuli at cloud base is very sensitive to changes in environmental conditions, while process models suggest the opposite. To understand and resolve this contradiction, we propose to organize a field campaign aimed at quantifying the physical properties of tradecumuli (e.g., cloud fraction and water content) as a function of the large-scale environment. Beyond a better understanding of clouds-circulation coupling processes, the campaign will provide a reference data set that may be used as a benchmark for advancing the modelling and the satellite remote sensing of clouds and circulation. It will also be an opportunity for complementary investigations such as evaluating model convective parameterizations or studying the role of ocean mesoscale eddies in air-sea interactions and convective organization.

  18. Generic reactive transport codes as flexible tools to integrate soil organic matter degradation models with water, transport and geochemistry in soils

    NASA Astrophysics Data System (ADS)

    Jacques, Diederik; Gérard, Fréderic; Mayer, Uli; Simunek, Jirka; Leterme, Bertrand

    2016-04-01

    A large number of organic matter degradation, CO2 transport and dissolved organic matter models have been developed during the last decades. However, organic matter degradation models are in many cases strictly hard-coded in terms of organic pools, degradation kinetics and dependency on environmental variables. The scientific input of the model user is typically limited to the adjustment of input parameters. In addition, the coupling with geochemical soil processes including aqueous speciation, pH-dependent sorption and colloid-facilitated transport are not incorporated in many of these models, strongly limiting the scope of their application. Furthermore, the most comprehensive organic matter degradation models are combined with simplified representations of flow and transport processes in the soil system. We illustrate the capability of generic reactive transport codes to overcome these shortcomings. The formulations of reactive transport codes include a physics-based continuum representation of flow and transport processes, while biogeochemical reactions can be described as equilibrium processes constrained by thermodynamic principles and/or kinetic reaction networks. The flexibility of these type of codes allows for straight-forward extension of reaction networks, permits the inclusion of new model components (e.g.: organic matter pools, rate equations, parameter dependency on environmental conditions) and in such a way facilitates an application-tailored implementation of organic matter degradation models and related processes. A numerical benchmark involving two reactive transport codes (HPx and MIN3P) demonstrates how the process-based simulation of transient variably saturated water flow (Richards equation), solute transport (advection-dispersion equation), heat transfer and diffusion in the gas phase can be combined with a flexible implementation of a soil organic matter degradation model. The benchmark includes the production of leachable organic matter and inorganic carbon in the aqueous and gaseous phases, as well as different decomposition functions with first-order, linear dependence or nonlinear dependence on a biomass pool. In addition, we show how processes such as local bioturbation (bio-diffusion) can be included implicitly through a Fickian formulation of transport of soil organic matter. Coupling soil organic matter models with generic and flexible reactive transport codes offers a valuable tool to enhance insights into coupled physico-chemical processes at different scales within the scope of C-biogeochemical cycles, possibly linked with other chemical elements such as plant nutrients and pollutants.

  19. [Coupling AFM fluid imaging with micro-flocculation filtration process for the technological optimization].

    PubMed

    Zheng, Bei; Ge, Xiao-peng; Yu, Zhi-yong; Yuan, Sheng-guang; Zhang, Wen-jing; Sun, Jing-fang

    2012-08-01

    Atomic force microscope (AFM) fluid imaging was applied to the study of micro-flocculation filtration process and the optimization of micro-flocculation time and the agitation intensity of G values. It can be concluded that AFM fluid imaging proves to be a promising tool in the observation and characterization of floc morphology and the dynamic coagulation processes under aqueous environmental conditions. Through the use of AFM fluid imaging technique, optimized conditions for micro-flocculation time of 2 min and the agitation intensity (G value) of 100 s(-1) were obtained in the treatment of dye-printing industrial tailing wastewater by the micro-flocculation filtration process with a good performance.

  20. Flexible Environmental Modeling with Python and Open - GIS

    NASA Astrophysics Data System (ADS)

    Pryet, Alexandre; Atteia, Olivier; Delottier, Hugo; Cousquer, Yohann

    2015-04-01

    Numerical modeling now represents a prominent task of environmental studies. During the last decades, numerous commercial programs have been made available to environmental modelers. These software applications offer user-friendly graphical user interfaces that allow an efficient management of many case studies. However, they suffer from a lack of flexibility and closed-source policies impede source code reviewing and enhancement for original studies. Advanced modeling studies require flexible tools capable of managing thousands of model runs for parameter optimization, uncertainty and sensitivity analysis. In addition, there is a growing need for the coupling of various numerical models associating, for instance, groundwater flow modeling to multi-species geochemical reactions. Researchers have produced hundreds of open-source powerful command line programs. However, there is a need for a flexible graphical user interface allowing an efficient processing of geospatial data that comes along any environmental study. Here, we present the advantages of using the free and open-source Qgis platform and the Python scripting language for conducting environmental modeling studies. The interactive graphical user interface is first used for the visualization and pre-processing of input geospatial datasets. Python scripting language is then employed for further input data processing, call to one or several models, and post-processing of model outputs. Model results are eventually sent back to the GIS program, processed and visualized. This approach combines the advantages of interactive graphical interfaces and the flexibility of Python scripting language for data processing and model calls. The numerous python modules available facilitate geospatial data processing and numerical analysis of model outputs. Once input data has been prepared with the graphical user interface, models may be run thousands of times from the command line with sequential or parallel calls. We illustrate this approach with several case studies in groundwater hydrology and geochemistry and provide links to several python libraries that facilitate pre- and post-processing operations.

  1. The Earth System Prediction Suite: Toward a Coordinated U.S. Modeling Capability

    DOE PAGES

    Theurich, Gerhard; DeLuca, C.; Campbell, T.; ...

    2016-08-22

    The Earth System Prediction Suite (ESPS) is a collection of flagship U.S. weather and climate models and model components that are being instrumented to conform to interoperability conventions, documented to follow metadata standards, and made available either under open-source terms or to credentialed users. Furthermore, the ESPS represents a culmination of efforts to create a common Earth system model architecture, and the advent of increasingly coordinated model development activities in the United States. ESPS component interfaces are based on the Earth System Modeling Framework (ESMF), community-developed software for building and coupling models, and the National Unified Operational Prediction Capability (NUOPC)more » Layer, a set of ESMF-based component templates and interoperability conventions. Our shared infrastructure simplifies the process of model coupling by guaranteeing that components conform to a set of technical and semantic behaviors. The ESPS encourages distributed, multiagency development of coupled modeling systems; controlled experimentation and testing; and exploration of novel model configurations, such as those motivated by research involving managed and interactive ensembles. ESPS codes include the Navy Global Environmental Model (NAVGEM), the Hybrid Coordinate Ocean Model (HYCOM), and the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS); the NOAA Environmental Modeling System (NEMS) and the Modular Ocean Model (MOM); the Community Earth System Model (CESM); and the NASA ModelE climate model and the Goddard Earth Observing System Model, version 5 (GEOS-5), atmospheric general circulation model.« less

  2. The Earth System Prediction Suite: Toward a Coordinated U.S. Modeling Capability

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Theurich, Gerhard; DeLuca, C.; Campbell, T.

    The Earth System Prediction Suite (ESPS) is a collection of flagship U.S. weather and climate models and model components that are being instrumented to conform to interoperability conventions, documented to follow metadata standards, and made available either under open-source terms or to credentialed users. Furthermore, the ESPS represents a culmination of efforts to create a common Earth system model architecture, and the advent of increasingly coordinated model development activities in the United States. ESPS component interfaces are based on the Earth System Modeling Framework (ESMF), community-developed software for building and coupling models, and the National Unified Operational Prediction Capability (NUOPC)more » Layer, a set of ESMF-based component templates and interoperability conventions. Our shared infrastructure simplifies the process of model coupling by guaranteeing that components conform to a set of technical and semantic behaviors. The ESPS encourages distributed, multiagency development of coupled modeling systems; controlled experimentation and testing; and exploration of novel model configurations, such as those motivated by research involving managed and interactive ensembles. ESPS codes include the Navy Global Environmental Model (NAVGEM), the Hybrid Coordinate Ocean Model (HYCOM), and the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS); the NOAA Environmental Modeling System (NEMS) and the Modular Ocean Model (MOM); the Community Earth System Model (CESM); and the NASA ModelE climate model and the Goddard Earth Observing System Model, version 5 (GEOS-5), atmospheric general circulation model.« less

  3. Terrestrial biogeochemical cycles: global interactions with the atmosphere and hydrology

    NASA Astrophysics Data System (ADS)

    Schimel, David S.; Kittel, Timothy G. F.; Parton, William J.

    1991-08-01

    Ecosystem scientists have developed a body of theory to predict the behaviour of biogeochemical cycles when exchanges with other ecosystems are small or prescribed. Recent environmental changes make it clear that linkages between ecosystems via atmospheric and hydrological transport have large effects on ecosystem dynamics when considered over time periods of a decade to a century, time scales relevant to contemporary humankind. Our ability to predict behaviour of ecosystems coupled by transport is limited by our ability (1) to extrapolate biotic function to large spatial scales and (2) to measure and model transport. We review developments in ecosystem theory, remote sensing, and geographical information systems (GIS) that support new efforts in spatial modeling. A paradigm has emerged to predict behaviour of ecosystems based on understanding responses to multiple resources (e.g., water, nutrients, light). Several ecosystem models couple primary production to decomposition and nutrient availability using the above paradigm. These models require a fairly small set of environmental variables to simulate spatial and temporal variation in rates of biogeochemical cycling. Simultaneously, techniques for inferring ecosystem behaviour from remotely measured canopy light interception are improving our ability to infer plant activity from satellite observations. Efforts have begun to couple models of transport in air and water to models of ecosystem function. Preliminary work indicates that coupling of transport and ecosystem processes alters the behaviour of earth system components (hydrology, terrestrial ecosystems, and the atmosphere) from that of an uncoupled mode.

  4. A life cycle assessment of environmental performances of two combustion- and gasification-based waste-to-energy technologies.

    PubMed

    Arena, Umberto; Ardolino, Filomena; Di Gregorio, Fabrizio

    2015-07-01

    An attributional life cycle analysis (LCA) was developed to compare the environmental performances of two waste-to-energy (WtE) units, which utilize the predominant technologies among those available for combustion and gasification processes: a moving grate combustor and a vertical shaft gasifier coupled with direct melting. The two units were assumed to be fed with the same unsorted residual municipal waste, having a composition estimated as a European average. Data from several plants in operation were processed by means of mass and energy balances, and on the basis of the flows and stocks of materials and elements inside and throughout the two units, as provided by a specific substance flow analysis. The potential life cycle environmental impacts related to the operations of the two WtE units were estimated by means of the Impact 2002+ methodology. They indicate that both the technologies have sustainable environmental performances, but those of the moving grate combustion unit are better for most of the selected impact categories. The analysis of the contributions from all the stages of each specific technology suggests where improvements in technological solutions and management criteria should be focused to obtain further and remarkable environmental improvements. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Inductively coupled plasma-mass spectrometry as an element-specific detector for field-flow fractionation particle separation

    USGS Publications Warehouse

    Taylor, Howard E.; Garbarino, John R.; Murphy, Deirdre M.; Beckett, Ronald

    1992-01-01

    An inductively coupled plasma-mass spectrometer was used for the quantitative measurement of trace elements In specific,submicrometer size-fraction particulates, separated by sedimentation field-flow fractionation. Fractions were collected from the eluent of the field-flow fractionation centrifuge and nebulized, with a Babington-type pneumatic nebulizer, into an argon inductively coupled plasma-mass spectrometer. Measured Ion currents were used to quantify the major, minor, and trace element composition of the size-separated colloidal (< 1-microm diameter) particulates. The composition of surface-water suspended matter collected from the Yarra and Darling rivers in Australia is presented to illustrate the usefulness of this tool for characterizing environmental materials. An adsorption experiment was performed using cadmium lon to demonstrate the utility for studying the processes of trace metal-suspended sediment interactions and contaminant transport in natural aquatic systems.

  6. Understanding The Role of Mate Selection Processes in Couples' Pair-Bonding Behavior.

    PubMed

    Horwitz, Briana N; Reynolds, Chandra A; Walum, Hasse; Ganiban, Jody; Spotts, Erica L; Reiss, David; Lichtenstein, Paul; Neiderhiser, Jenae M

    2016-01-01

    Couples are similar in their pair-bonding behavior, yet the reasons for this similarity are often unclear. A common explanation is phenotypic assortment, whereby individuals select partners with similar heritable characteristics. Alternatively, social homogamy, whereby individuals passively select partners with similar characteristic due to shared social backgrounds, is rarely considered. We examined whether phenotypic assortment and/or social homogamy can contribute to mate similarity using a twin-partner design. The sample came from the Twin and Offspring Study in Sweden, which included 876 male and female monozygotic and same-sex dizygotic twins plus their married or cohabitating partners. Results showed that variance in pair-bonding behavior was attributable to genetic and nonshared environmental factors. Furthermore, phenotypic assortment accounted for couple similarity in pair-bonding behavior. This suggests that individuals' genetically based characteristics are involved in their selection of mates with similar pair-bonding behavior.

  7. Controls on the Environmental Fate of Compounds Controlled by Coupled Hydrologic and Reactive Processes

    NASA Astrophysics Data System (ADS)

    Hixson, J.; Ward, A. S.; McConville, M.; Remucal, C.

    2017-12-01

    Current understanding of how compounds interact with hydrologic processes or reactive processes have been well established. However, the environmental fate for compounds that interact with hydrologic AND reactive processes is not well known, yet critical in evaluating environmental risk. Evaluations of risk are often simplified to homogenize processes in space and time and to assess processes independently of one another. However, we know spatial heterogeneity and time-variable reactivities complicate predictions of environmental transport and fate, and is further complicated by the interaction of these processes, limiting our ability to accurately predict risk. Compounds that interact with both systems, such as photolytic compounds, require that both components are fully understood in order to predict transport and fate. Release of photolytic compounds occurs through both unintentional releases and intentional loadings. Evaluating risks associated with unintentional releases and implementing best management practices for intentional releases requires an in-depth understanding of the sensitivity of photolytic compounds to external controls. Lampricides, such as 3-trifluoromethyl-4-nitrophenol (TFM), are broadly applied in the Great Lakes system to control the population of invasive sea lamprey. Over-dosing can yield fish kills and other detrimental impacts. Still, planning accounts for time of passage and dilution, but not the interaction of the physical and chemical systems (i.e., storage in the hyporheic zone and time-variable decay rates). In this study, we model a series of TFM applications to test the efficacy of dosing as a function of system characteristics. Overall, our results demonstrate the complexity associated with photo-sensitive compounds through stream-hyporheic systems, and highlight the need to better understand how physical and chemical systems interact to control transport and fate in the environment.

  8. The UKC2 regional coupled prediction system

    NASA Astrophysics Data System (ADS)

    Castillo, Juan; Lewis, Huw; Graham, Jennifer; Saulter, Andrew; Arnold, Alex; Fallmann, Joachim; Martinez de la Torre, Alberto; Blyth, Eleanor; Bricheno, Lucy

    2017-04-01

    It is hypothesized that more accurate prediction and warning of natural hazards, such as of the impacts of severe weather through the environment, requires a more integrated approach to forecasting. This approach also delivers research benefits through providing tools with which to explore the known interactions and feedbacks between different physical and biogeochemical components of the environment across sky, sea and land. This hypothesis is being tested in a UK regional context at km-scale through the UK Environmental Prediction Project. This presentation will provide an introduction to the UKC2 UK Environmental Prediction research system. This incorporates models of the atmosphere (Met Office Unified Model), land surface (JULES), shelf-sea ocean (NEMO) and ocean waves (WAVEWATCH III). These components are coupled (via OASIS3-MCT libraries) at unprecedentedly high resolution across the UK and the wider north-west European regional domain. A research framework has been established to explore the representation of feedback processes in coupled and uncoupled modes, providing a unique new research tool for UK environmental science. The presentation will highlight work undertaken to review and improve the computational cost of running these systems for efficient research application. Research will be presented highlighting case study evaluation on the sensitivity of the ocean and surface waves to the representation of feedbacks to the atmosphere, and on the sensitivity of weather systems and boundary layer cloud development to the exchange of heat and momentum at the ocean surface modified through sea surface temperature and wave-induced roughness. The presentation will discuss plans for future development through UKC3 and beyond.

  9. An innovative computationally efficient hydromechanical coupling approach for fault reactivation in geological subsurface utilization

    NASA Astrophysics Data System (ADS)

    Adams, M.; Kempka, T.; Chabab, E.; Ziegler, M.

    2018-02-01

    Estimating the efficiency and sustainability of geological subsurface utilization, i.e., Carbon Capture and Storage (CCS) requires an integrated risk assessment approach, considering the occurring coupled processes, beside others, the potential reactivation of existing faults. In this context, hydraulic and mechanical parameter uncertainties as well as different injection rates have to be considered and quantified to elaborate reliable environmental impact assessments. Consequently, the required sensitivity analyses consume significant computational time due to the high number of realizations that have to be carried out. Due to the high computational costs of two-way coupled simulations in large-scale 3D multiphase fluid flow systems, these are not applicable for the purpose of uncertainty and risk assessments. Hence, an innovative semi-analytical hydromechanical coupling approach for hydraulic fault reactivation will be introduced. This approach determines the void ratio evolution in representative fault elements using one preliminary base simulation, considering one model geometry and one set of hydromechanical parameters. The void ratio development is then approximated and related to one reference pressure at the base of the fault. The parametrization of the resulting functions is then directly implemented into a multiphase fluid flow simulator to carry out the semi-analytical coupling for the simulation of hydromechanical processes. Hereby, the iterative parameter exchange between the multiphase and mechanical simulators is omitted, since the update of porosity and permeability is controlled by one reference pore pressure at the fault base. The suggested procedure is capable to reduce the computational time required by coupled hydromechanical simulations of a multitude of injection rates by a factor of up to 15.

  10. Regional-scale geomechanical impact assessment of underground coal gasification by coupled 3D thermo-mechanical modeling

    NASA Astrophysics Data System (ADS)

    Otto, Christopher; Kempka, Thomas; Kapusta, Krzysztof; Stańczyk, Krzysztof

    2016-04-01

    Underground coal gasification (UCG) has the potential to increase the world-wide coal reserves by utilization of coal deposits not mineable by conventional methods. The UCG process involves combusting coal in situ to produce a high-calorific synthesis gas, which can be applied for electricity generation or chemical feedstock production. Apart from its high economic potentials, UCG may induce site-specific environmental impacts such as fault reactivation, induced seismicity and ground subsidence, potentially inducing groundwater pollution. Changes overburden hydraulic conductivity resulting from thermo-mechanical effects may introduce migration pathways for UCG contaminants. Due to the financial efforts associated with UCG field trials, numerical modeling has been an important methodology to study coupled processes considering UCG performance. Almost all previous UCG studies applied 1D or 2D models for that purpose, that do not allow to predict the performance of a commercial-scale UCG operation. Considering our previous findings, demonstrating that far-field models can be run at a higher computational efficiency by using temperature-independent thermo-mechanical parameters, representative coupled simulations based on complex 3D regional-scale models were employed in the present study. For that purpose, a coupled thermo-mechanical 3D model has been developed to investigate the environmental impacts of UCG based on a regional-scale of the Polish Wieczorek mine located in the Upper Silesian Coal Basin. The model size is 10 km × 10 km × 5 km with ten dipping lithological layers, a double fault and 25 UCG reactors. Six different numerical simulation scenarios were investigated, considering the transpressive stress regime present in that part of the Upper Silesian Coal Basin. Our simulation results demonstrate that the minimum distance between the UCG reactors is about the six-fold of the coal seam thickness to avoid hydraulic communication between the single UCG reactors. Fault reactivation resulting from fault shear and normal displacements is discussed under consideration of potentially induced seismicity. Here, the coupled simulation results indicate that seismic hazard during UCG operation remains negligible with a seismic moment magnitude of MW < 3.

  11. Trace element-protein interactions in endolymph from the inner ear of fish: implications for environmental reconstructions using fish otolith chemistry.

    PubMed

    Thomas, Oliver R B; Ganio, Katherine; Roberts, Blaine R; Swearer, Stephen E

    2017-03-22

    Otoliths, the biomineralised hearing "ear stones" from the inner ear of fish, grow throughout the lifespan of an individual, with deposition of alternating calciferous and proteinaceous bands occurring daily. Trace element : calcium ratios within daily increments measured by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are often used in fisheries science to reconstruct environmental histories. There is, however, considerable uncertainty as to which elements are interacting with either the proteinaceous or calciferous zones of the otolith, and thus their utility as indicators of environmental change. To answer this, we used size exclusion chromatography-inductively coupled plasma-mass spectrometry (SEC-ICP-MS) of endolymph, the otolith growth medium, to determine the binding interactions for a range of elements. In addition, we used solution ICP-MS to quantify element concentrations in paired otolith and endolymph samples and determined relative enrichment factors for each. We found 12 elements that are present only in the proteinaceous fraction, 6 that are present only in the salt fraction, and 4 that are present in both. These findings have important implications for the reconstruction of environmental histories based on changes in otolith elemental composition: (1) elements occurring only in the salt fraction are most likely to reflect changes in the physico-chemical environment experienced during life; (2) elements occurring only in the proteinaceous fraction are more likely to reflect physiological rather than environmental events; and (3) elements occurring in both the salt and proteinaceous fractions are likely to be informative about both endogenous and exogenous processes, potentially reducing their utility in environmental reconstructions.

  12. The Shale Hills Sensorium for Embedded Sensors, Simulation, & Visualization: A Prototype for Land-Vegetation-Atmosphere Interactions

    NASA Astrophysics Data System (ADS)

    Duffy, C.

    2008-12-01

    The future of environmental observing systems will utilize embedded sensor networks with continuous real- time measurement of hydrologic, atmospheric, biogeochemical, and ecological variables across diverse terrestrial environments. Embedded environmental sensors, benefitting from advances in information sciences, networking technology, materials science, computing capacity, and data synthesis methods, are undergoing revolutionary change. It is now possible to field spatially-distributed, multi-node sensor networks that provide density and spatial coverage previously accessible only via numerical simulation. At the same time, computational tools are advancing rapidly to the point where it is now possible to simulate the physical processes controlling individual parcels of water and solutes through the complete terrestrial water cycle. Our goal for the Penn State Critical Zone Observatory is to apply environmental sensor arrays, integrated hydrologic models, and state-of-the-art visualization deployed and coordinated at a testbed within the Penn State Experimental Forest. The Shale Hills Hydro_Sensorium prototype proposed here is designed to observe land-atmosphere interactions in four-dimensional (space and time). The term Hydro_Sensorium implies the totality of physical sensors, models and visualization tools that allow us to perceive the detailed space and time complexities of the water and energy cycle for a watershed or river basin for all physical states and fluxes (groundwater, soil moisture, temperature, streamflow, latent heat, snowmelt, chemistry, isotopes etc.). This research will ultimately catalyze the study of complex interactions between the land surface, subsurface, biological and atmospheric systems over a broad range of scales. The sensor array would be real-time and fully controllable by remote users for "computational steering" and data fusion. Presently fully-coupled physical models are being developed that link the atmosphere-land-vegetation-subsurface system into a fully-coupled distributed system. During the last 5 years the Penn State Integrated Hydrologic Modeling System has been under development as an open-source community modeling project funded by NSF EAR/GEO and NSF CBET/ENG. PIHM represents a strategy for the formulation and solution of fully-coupled process equations at the watershed and river basin scales, and includes a tightly coupled GIS tool for data handling, domain decomposition, optimal unstructured grid generation, and model parameterization. The sensor and simulation system has the following elements: 1) extensive, spatially-distributed, non- invasive, smart sensor networks to gather massive geologic, hydrologic, and geochemical data; 2) stochastic information fusion methods; 3) spatially-explicit multiphysics models/solutions of the land-vegetation- atmosphere system; and 4) asynchronous, parallel/distributed, adaptive algorithms for rapidly simulating the states of a basin at high resolution, 5) signal processing tools for data mining and parameter estimation, and 6) visualization tools. The prototype proposed sensor array and simulation system proposed here will offer a coherent new approach to environmental predictions with a fully integrated observing system design. We expect that the Shale Hills Hydro_Sensorium may provide the needed synthesis of information and conceptualization necessary to advance predictive understanding in complex hydrologic systems.

  13. The Role of RNA in Biological Phase Separations.

    PubMed

    Fay, Marta M; Anderson, Paul J

    2018-05-10

    Phase transitions that alter the physical state of ribonucleoprotein particles contribute to the spacial and temporal organization of the densely packed intracellular environment. This allows cells to organize biologically coupled processes as well as respond to environmental stimuli. RNA plays a key role in phase separation events that modulate various aspects of RNA metabolism. Here, we review the role that RNA plays in ribonucleoprotein phase separations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Model approaches for estimating the influence of time-varying socio-environmental factors on macroparasite transmission in two endemic regions

    PubMed Central

    ZHONG, BO; CARLTON, ELIZABETH J.; SPEAR, ROBERT C.

    2009-01-01

    The environmental determinants of vector- and host-borne diseases include time-varying components that modify key transmission parameters, resulting in transient couplings between environmental phenomena and transmission processes. While some time-varying drivers are periodic in nature, some are aperiodic, such as those that involve episodic events or complex patterns of human behavior. Understanding these couplings can allow for prediction of periods of peak infection risk, and ultimately presents opportunities for optimizing intervention selection and timing. Schistosome macroparasites of humans exhibit multiple free-living stages as well as intermediate hosts, and are thus model organisms for illustrating the influence of environmental forcing on transmission. Time-varying environmental factors, termed gating functions, for schistosomes include larval response to temperature and rainfall, seasonal water contact patterns and snail population dynamics driven by weather variables. The biological bases for these modifiers are reviewed, and their values are estimated and incorporated into a transmission model that simulates a multi-year period in two schistosomiasis endemic regions. Modeling results combined with a scale dependent correlation analysis indicate the end effect of these site-specific gating functions is to strongly govern worm burden in these communities, in a manner particularly sensitive to the hydrological differences between sites. Two classes of gating functions were identified, those that act in concert to modify human infection (and determine worm acquisition late in the season), and those that act on snail infection (and determine early season worm acquisition). The importance of these factors for control programs and surveillance is discussed. PMID:20454601

  15. Global Environmental Multiscale model - a platform for integrated environmental predictions

    NASA Astrophysics Data System (ADS)

    Kaminski, Jacek W.; Struzewska, Joanna; Neary, Lori; Dearden, Frank

    2017-04-01

    The Global Environmental Multiscale model was developed by the Government of Canada as an operational weather prediction model in the mid-1990s. Subsequently, it was used as the host meteorological model for an on-line implementation of air quality chemistry and aerosols from global to the meso-gamma scale. Further model developments led to the vertical extension of the modelling domain to include stratospheric chemistry, aerosols, and formation of polar stratospheric clouds. In parallel, the modelling platform was used for planetary applications where dynamical, radiative transfer and chemical processes in the atmosphere of Mars were successfully simulated. Undoubtedly, the developed modelling platform can be classified as an example capable of the seamless and coupled modelling of the dynamics and chemistry of planetary atmospheres. We will present modelling results for global, regional, and local air quality episodes and the long-term air quality trends. Upper troposphere and lower stratosphere modelling results will be presented in terms of climate change and subsonic aviation emissions modelling. Model results for the atmosphere of Mars will be presented in the context of the 2016 ExoMars mission and the anticipated observations from the NOMAD instrument. Also, we will present plans and the design to extend the GEM model to the F region with further coupling with a magnetospheric model that extends to 15 Re.

  16. Is Earth F**ked? Dynamical Futility of Global Environmental Management and Possibilities for Sustainability via Direct Action Activism

    NASA Astrophysics Data System (ADS)

    wErnEr, B.

    2012-12-01

    Environmental challenges are dynamically generated within the dominant global culture principally by the mismatch between short-time-scale market and political forces driving resource extraction/use and longer-time-scale accommodations of the Earth system to these changes. Increasing resource demand is leading to the development of two-way, nonlinear interactions between human societies and environmental systems that are becoming global in extent, either through globalized markets and other institutions or through coupling to global environmental systems such as climate. These trends are further intensified by dissipation-reducing technological advances in transactions, communication and transport, which suppress emergence of longer-time-scale economic and political levels of description and facilitate long-distance connections, and by predictive environmental modeling, which strengthens human connections to a short-time-scale virtual Earth, and weakens connections to the longer time scales of the actual Earth. Environmental management seeks to steer fast scale economic and political interests of a coupled human-environmental system towards longer-time-scale consideration of benefits and costs by operating within the confines of the dominant culture using a linear, engineering-type connection to the system. Perhaps as evidenced by widespread inability to meaningfully address such global environmental challenges as climate change and soil degradation, nonlinear connections reduce the ability of managers to operate outside coupled human-environmental systems, decreasing their effectiveness in steering towards sustainable interactions and resulting in managers slaved to short-to-intermediate-term interests. In sum, the dynamics of the global coupled human-environmental system within the dominant culture precludes management for stable, sustainable pathways and promotes instability. Environmental direct action, resistance taken from outside the dominant culture, as in protests, blockades and sabotage by indigenous peoples, workers, anarchists and other activist groups, increases dissipation within the coupled system over fast to intermediate scales and pushes for changes in the dominant culture that favor transition to a stable, sustainable attractor. These dynamical relationships are illustrated and explored using a numerical model that simulates the short-, intermediate- and long-time-scale dynamics of the coupled human-environmental system. At fast scales, economic and political interests exploit environmental resources through a maze of environmental management and resistance, guided by virtual Earth predictions. At intermediate scales, managers become slaved to economic and political interests, which adapt to and repress resistance, and resistance is guided by patterns of environmental destruction. At slow scales, resistance interacts with the cultural context, which co-evolves with the environment. The transition from unstable dynamics to sustainability is sensitively dependent on the level of participation in and repression of resistance. Because of their differing impact inside and outside the dominant culture, virtual Earth predictions can either promote or oppose sustainability. Supported by the National Science Foundation, Geomorphology and Land Use Dynamics Program.

  17. Stability of Intercellular Exchange of Biochemical Substances Affected by Variability of Environmental Parameters

    NASA Astrophysics Data System (ADS)

    Mihailović, Dragutin T.; Budinčević, Mirko; Balaž, Igor; Mihailović, Anja

    Communication between cells is realized by exchange of biochemical substances. Due to internal organization of living systems and variability of external parameters, the exchange is heavily influenced by perturbations of various parameters at almost all stages of the process. Since communication is one of essential processes for functioning of living systems it is of interest to investigate conditions for its stability. Using previously developed simplified model of bacterial communication in a form of coupled difference logistic equations we investigate stability of exchange of signaling molecules under variability of internal and external parameters.

  18. Environmentally benign semiconductor processing for dielectric etch

    NASA Astrophysics Data System (ADS)

    Liao, Marci Yi-Ting

    Semiconductor processing requires intensive usage of chemicals, electricity, and water. Such intensive resource usage leaves a large impact on the environment. For instance, in Silicon Valley, the semiconductor industry is responsible for 80% of the hazardous waste sites contaminated enough to require government assistance. Research on environmentally benign semiconductor processing is needed to reduce the environmental impact of the semiconductor industry. The focus of this dissertation is on the environmental impact of one aspect of semiconductor processing: patterning of dielectric materials. Plasma etching of silicon dioxide emits perfluorocarbons (PFCs) gases, like C2F6 and CF4, into the atmosphere. These gases are super global warming/greenhouse gases because of their extremely long atmospheric lifetimes and excellent infrared absorption properties. We developed the first inductively coupled plasma (ICP) abatement device for destroying PFCs downstream of a plasma etcher. Destruction efficiencies of 99% and 94% can be obtained for the above mentioned PFCs, by using O 2 as an additive gas. Our results have lead to extensive modeling in academia as well as commercialization of the ICP abatement system. Dielectric patterning of hi-k materials for future device technology brings different environment challenges. The uncertainty of the hi-k material selection and the patterning method need to be addressed. We have evaluated the environmental impact of three different dielectric patterning methods (plasma etch, wet etch and chemical-mechanical polishing), as well as, the transistor device performances associated with the patterning methods. Plasma etching was found to be the most environmentally benign patterning method, which also gives the best device performance. However, the environmental concern for plasma etching is the possibility of cross-contamination from low volatility etch by-products. Therefore, mass transfer in a plasma etcher for a promising hi-k dielectric material, ZrO2, was studied. A novel cross-contamination sampling technique was developed, along with a mass transfer model.

  19. Global methane and nitrous oxide emissions from terrestrial ecosystems due to multiple environmental changes

    DOE PAGES

    Tian, Hanqin; Chen, Guangsheng; Lu, Chaoqun; ...

    2015-03-16

    Greenhouse gas (GHG)-induced climate change is among the most pressing sustainability challenges facing humanity today, posing serious risks for ecosystem health. Methane (CH 4) and nitrous oxide (N 2O) are the two most important GHGs after carbon dioxide (CO 2), but their regional and global budgets are not well known. In this paper, we applied a process-based coupled biogeochemical model to concurrently estimate the magnitude and spatial and temporal patterns of CH 4 and N 2O fluxes as driven by multiple environmental changes, including climate variability, rising atmospheric CO 2, increasing nitrogen deposition, tropospheric ozone pollution, land use change, andmore » nitrogen fertilizer use.« less

  20. Influences of Coupled Hydrologic and Microbial Processes on River Corridor Biogeochemistry and Ecology

    NASA Astrophysics Data System (ADS)

    Scheibe, T. D.; Song, H. S.; Stegen, J.; Graham, E.; Bao, J.; Goldman, A.; Zhou, T.; Crump, A.; Hou, Z.; Hammond, G. E.; Chen, X.; Huang, M.; Zhang, X.; Nelson, W. C.; Garayburu-Caruso, V. A.

    2017-12-01

    The exchange of water between rivers and surrounding subsurface environments (hydrologic exchange flows or HEFs) is a vital aspect of river ecology and watershed function. HEFs play a key role in water quality, nutrient cycling, and ecosystem health, and they modulate water temperatures and enhance exchange of terrestrial and aquatic nutrients, which lead to elevated biogeochemical activity. However, these coupled hydrologic and microbiological processes are not well understood, particularly in the context of large managed river systems with highly variable discharge, and are poorly represented in system-scale quantitative models. Using the 75 km Hanford Reach of the Columbia River as the research domain, we apply high-resolution flow simulations supported by field observations to understand how variable river discharge interacts with hydromorphic and hydrogeologic structures to generate HEFs and distributions of subsurface residence times. We combine this understanding of hydrologic processes with microbiological activity measurements and reactive transport models to elucidate the holistic impacts of variable discharge on river corridor (surface and subsurface) ecosystems. In particular, our project seeks to develop and test new conceptual and numerical models that explicitly incorporate i) the character (chemical speciation and thermodynamics) of natural organic matter as it varies along flow paths and through mixing of groundwater and surface water, and ii) the history-dependent response of microbial communities to varying time scales of inundation associated with fluctuations in river discharge. The results of these high-resolution mechanistic models are guiding formulation and parameterization of reduced-order models applicable at reach to watershed scales. New understanding of coupled hydrology and microbiology in the river corridor will play a key role in reduction of uncertainties associated with major Earth system biogeochemical fluxes, improving predictions of environmental and human impacts on water quality and riverine ecosystems, and supporting environmentally responsible management of linked energy-water systems.

  1. Mining Environmental Data from a Coupled Modelling System to Examine the Impact of Agricultural Management Practices on Groundwater and Air Quality

    NASA Astrophysics Data System (ADS)

    Garcia, V.; Cooter, E. J.; Hayes, B.; Murphy, M. S.; Bash, J. O.

    2014-12-01

    Excess nitrogen (N) resulting from current agricultural management practices can leach into sources of drinking water as nitrate, increasing human health risks of 'blue baby syndrome', hypertension, and some cancers and birth defects. Nitrogen also enters the atmosphere from land surfaces forming air pollution increasing human health risks of pulmonary and cardio-vascular disease. Characterizing and attributing nitrogen from agricultural management practices is difficult due to the complex and inter-related chemical and biological reactions associated with the nitrogen cascade. Coupled physical process-based models, however, present new opportunities to investigate relationships among environmental variables on new scales; particularly because they link emission sources with meteorology and the pollutant concentration ultimately found in the environment. In this study, we applied a coupled meteorology (NOAA-WRF), agricultural (USDA-EPIC) and air quality modelling system (EPA-CMAQ) to examine the impact of nitrogen inputs from corn production on ecosystem and human health and wellbeing. The coupled system accounts for the nitrogen flux between the land surface and air, and the soil surface and groundwater, providing a unique opportunity to examine the effect of management practices such as type and timing of fertilization, tilling and irrigation on both groundwater and air quality across the conterminous US. In conducting the study, we first determined expected relationships based on literature searches and then identified model variables as direct or surrogate variables. We performed extensive and methodical multi-variate regression modelling and variable selection to examine associations between agricultural management practices and environmental condition. We then applied the regression model to predict and contrast pollution levels between two corn production scenarios (Figure 1). Finally, we applied published health functions (e.g., spina bifida and cardio-vascular mortality rates) and economic impact functions (e.g., loss of work/school days, decontamination of drinking water wells). The results of this analysis will be presented at the conference.

  2. Graphene oxide windows for in situ environmental cell photoelectron spectroscopy.

    PubMed

    Kolmakov, Andrei; Dikin, Dmitriy A; Cote, Laura J; Huang, Jiaxing; Abyaneh, Majid Kazemian; Amati, Matteo; Gregoratti, Luca; Günther, Sebastian; Kiskinova, Maya

    2011-08-28

    The performance of new materials and devices often depends on processes taking place at the interface between an active solid element and the environment (such as air, water or other fluids). Understanding and controlling such interfacial processes require surface-specific spectroscopic information acquired under real-world operating conditions, which can be challenging because standard approaches such as X-ray photoelectron spectroscopy generally require high-vacuum conditions. The state-of-the-art approach to this problem relies on unique and expensive apparatus including electron analysers coupled with sophisticated differentially pumped lenses. Here, we develop a simple environmental cell with graphene oxide windows that are transparent to low-energy electrons (down to 400 eV), and demonstrate the feasibility of X-ray photoelectron spectroscopy measurements on model samples such as gold nanoparticles and aqueous salt solution placed on the back side of a window. These proof-of-principle results show the potential of using graphene oxide, graphene and other emerging ultrathin membrane windows for the fabrication of low-cost, single-use environmental cells compatible with commercial X-ray and Auger microprobes as well as scanning or transmission electron microscopes.

  3. Collaborative Project. Understanding the effects of tides and eddies on the ocean dynamics, sea ice cover and decadal/centennial climate prediction using the Regional Arctic Climate Model (RACM)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hutchings, Jennifer; Joseph, Renu

    2013-09-14

    The goal of this project is to develop an eddy resolving ocean model (POP) with tides coupled to a sea ice model (CICE) within the Regional Arctic System Model (RASM) to investigate the importance of ocean tides and mesoscale eddies in arctic climate simulations and quantify biases associated with these processes and how their relative contribution may improve decadal to centennial arctic climate predictions. Ocean, sea ice and coupled arctic climate response to these small scale processes will be evaluated with regard to their influence on mass, momentum and property exchange between oceans, shelf-basin, ice-ocean, and ocean-atmosphere. The project willmore » facilitate the future routine inclusion of polar tides and eddies in Earth System Models when computing power allows. As such, the proposed research addresses the science in support of the BER’s Climate and Environmental Sciences Division Long Term Measure as it will improve the ocean and sea ice model components as well as the fully coupled RASM and Community Earth System Model (CESM) and it will make them more accurate and computationally efficient.« less

  4. Targeting couple and parent-child coercion to improve health behaviors.

    PubMed

    Smith Slep, Amy M; Heyman, Richard E; Mitnick, Danielle M; Lorber, Michael F; Beauchaine, Theodore P

    2018-02-01

    This phase of the NIH Science of Behavior Change program emphasizes an "experimental medicine approach to behavior change," that seeks to identify targets related to stress reactivity, self-regulation, and social processes for maximal effects on multiple health outcomes. Within this framework, our project focuses on interpersonal processes associated with health: coercive couple and parent-child conflict. Diabetes and poor oral health portend pain, distress, expense, loss of productivity, and even mortality. They share overlapping medical regimens, are driven by overlapping proximal health behaviors, and affect a wide developmental span, from early childhood to late adulthood. Coercive couple and parent-child conflict constitute potent and destructive influences on a wide range of adult and child health outcomes. Such interaction patterns give rise to disturbed environmental stress reactivity (e.g., disrupted sympathetic nervous and parasympathetic nervous systems) and a wide range of adverse health outcomes in children and adults, including dental caries, obesity, and diabetes-related metabolic markers. In this work, we seek to identify/develop/validate assays assessing coercion, identify/develop and test brief interventions to reduce coercion, and test whether changes in coercion trigger changes in health behaviors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Progress and challenges in coupled hydrodynamic-ecological estuarine modeling.

    PubMed

    Ganju, Neil K; Brush, Mark J; Rashleigh, Brenda; Aretxabaleta, Alfredo L; Del Barrio, Pilar; Grear, Jason S; Harris, Lora A; Lake, Samuel J; McCardell, Grant; O'Donnell, James; Ralston, David K; Signell, Richard P; Testa, Jeremy M; Vaudrey, Jamie M P

    2016-03-01

    Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear, because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In this review we present historical and modern perspectives on estuarine hydrodynamic and ecological modeling, consider model limitations, and address aspects of model linkage, skill assessment, and complexity. We discuss the balance between spatial and temporal resolution and present examples using different spatiotemporal scales. Finally, we recommend future lines of inquiry, approaches to balance complexity and uncertainty, and model transparency and utility. It is idealistic to think we can pursue a "theory of everything" for estuarine models, but recent advances suggest that models for both scientific investigations and management applications will continue to improve in terms of realism, precision, and accuracy.

  6. Progress and challenges in coupled hydrodynamic-ecological estuarine modeling

    USGS Publications Warehouse

    Ganju, Neil K.; Brush, Mark J.; Rashleigh, Brenda; Aretxabaleta, Alfredo L.; del Barrio, Pilar; Grear, Jason S.; Harris, Lora A.; Lake, Samuel J.; McCardell, Grant; O'Donnell, James; Ralston, David K.; Signell, Richard P.; Testa, Jeremy; Vaudrey, Jamie M. P.

    2016-01-01

    Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In this review, we present historical and modern perspectives on estuarine hydrodynamic and ecological modeling, consider model limitations, and address aspects of model linkage, skill assessment, and complexity. We discuss the balance between spatial and temporal resolution and present examples using different spatiotemporal scales. Finally, we recommend future lines of inquiry, approaches to balance complexity and uncertainty, and model transparency and utility. It is idealistic to think we can pursue a “theory of everything” for estuarine models, but recent advances suggest that models for both scientific investigations and management applications will continue to improve in terms of realism, precision, and accuracy.

  7. Progress and challenges in coupled hydrodynamic-ecological estuarine modeling

    PubMed Central

    Ganju, Neil K.; Brush, Mark J.; Rashleigh, Brenda; Aretxabaleta, Alfredo L.; del Barrio, Pilar; Grear, Jason S.; Harris, Lora A.; Lake, Samuel J.; McCardell, Grant; O’Donnell, James; Ralston, David K.; Signell, Richard P.; Testa, Jeremy M.; Vaudrey, Jamie M.P.

    2016-01-01

    Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear, because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In this review we present historical and modern perspectives on estuarine hydrodynamic and ecological modeling, consider model limitations, and address aspects of model linkage, skill assessment, and complexity. We discuss the balance between spatial and temporal resolution and present examples using different spatiotemporal scales. Finally, we recommend future lines of inquiry, approaches to balance complexity and uncertainty, and model transparency and utility. It is idealistic to think we can pursue a “theory of everything” for estuarine models, but recent advances suggest that models for both scientific investigations and management applications will continue to improve in terms of realism, precision, and accuracy. PMID:27721675

  8. Catalyst-free activation of methylene chloride and alkynes by amines in a three-component coupling reaction to synthesize propargylamines.

    PubMed

    Rawat, Vikas S; Bathini, Thulasiram; Govardan, S; Sreedhar, Bojja

    2014-09-14

    Propargylamines are synthesized via metal-free activation of the C-halogen bond of dihalomethanes and the C-H bond of terminal alkynes in a three-component coupling without catalyst or additional base and under mild reaction conditions. The dihalomethanes are used both as solvents as well as precursors for the methylene fragment (C1) in the final product. The scope of the reaction and the influence of various reaction variables has been investigated. A plausible reaction mechanism is proposed and the involvement of various intermediates that can be generated in situ in the process is discussed. The metal-free conditions also make this protocol environmentally benign and atom economical.

  9. Benthic-Pelagic Coupling: Effects on Nematode Communities along Southern European Continental Margins

    PubMed Central

    Pape, Ellen; Jones, Daniel O. B.; Manini, Elena; Bezerra, Tania Nara; Vanreusel, Ann

    2013-01-01

    Along a west-to-east axis spanning the Galicia Bank region (Iberian margin) and the Mediterranean basin, a reduction in surface primary productivity and in seafloor flux of particulate organic carbon was mirrored in the in situ organic matter quantity and quality within the underlying deep-sea sediments at different water depths (1200, 1900 and 3000 m). Nematode standing stock (abundance and biomass) and genus and trophic composition were investigated to evaluate downward benthic-pelagic coupling. The longitudinal decline in seafloor particulate organic carbon flux was reflected by a reduction in benthic phytopigment concentrations and nematode standing stock. An exception was the station sampled at the Galicia Bank seamount, where despite the maximal particulate organic carbon flux estimate, we observed reduced pigment levels and nematode standing stock. The strong hydrodynamic forcing at this station was believed to be the main cause of the local decoupling between pelagic and benthic processes. Besides a longitudinal cline in nematode standing stock, we noticed a west-to-east gradient in nematode genus and feeding type composition (owing to an increasing importance of predatory/scavenging nematodes with longitude) governed by potential proxies for food availability (percentage of nitrogen, organic carbon, and total organic matter). Within-station variability in generic composition was elevated in sediments with lower phytopigment concentrations. Standing stock appeared to be regulated by sedimentation rates and benthic environmental variables, whereas genus composition covaried only with benthic environmental variables. The coupling between deep-sea nematode assemblages and surface water processes evidenced in the present study suggests that it is likely that climate change will affect the composition and function of deep-sea nematodes. PMID:23565176

  10. Off the Shelf Fouling Management

    PubMed Central

    Rittschof, Daniel

    2017-01-01

    This chapter tells the story of a research thread that identified and modified a pharmaceutical that could be a component of environmentally benign fouling management coatings. First, I present the background context of biofouling and how fouling is managed. The major target of the research is disrupting transduction of a complex process in all macrofouling organisms: metamorphosis. Using a bioassay directed approach we first identified a pharmaceutical candidate. Then, based on structure function studies coupled with laboratory and field bioassays, we simplified the molecule, eliminating halogens and aromatic rings to a pharmacophore that could be readily broken down by bacteria. Next, we did further structure function studies coupled to lab and field bioassays of modifications that enabled delivery of the molecule in a variety of coatings. The outcome is a different way of thinking about managing fouling and concepts in which molecules are designed to perform a function and then degrade. This work is discussed in the context of existing fouling management approaches and business models which use long-lived broad-spectrum biocides which have consequences for human, environmental health, and food security. PMID:28613232

  11. Strategic behaviors and governance challenges in social-ecological systems

    NASA Astrophysics Data System (ADS)

    Muneepeerakul, Rachata; Anderies, John M.

    2017-08-01

    The resource management and environmental policy literature focuses on devising regulations and incentive structures to achieve desirable goals. It often presumes the existence of public infrastructure that actualizes these incentives and regulations through a process loosely referred to as `governance.' In many cases, it is not clear if and how such governance infrastructure can be created and supported. Here, we take a complex systems view in which `governance' is an emergent phenomenon generated by interactions between social, economic, and environmental (both built and natural) factors. We present a framework and formal stylized model to explore under what circumstances stable governance structures may emerge endogenously in coupled infrastructure systems comprising shared natural, social, and built infrastructures of which social-ecological systems are specific examples. The model allows us to derive general conditions for a sustainable coupled infrastructure system in which critical infrastructure (e.g., canals) is provided by a governing entity that enables resource users (e.g., farmers) to produce outputs from natural infrastructure (e.g., water) to meet their needs while supporting the governing entity.

  12. Temperature Dependence of the Energy Levels of Methylammonium Lead Iodide Perovskite from First-Principles.

    PubMed

    Saidi, Wissam A; Poncé, Samuel; Monserrat, Bartomeu

    2016-12-15

    Environmental effects and intrinsic energy-loss processes lead to fluctuations in the operational temperature of solar cells, which can profoundly influence their power conversion efficiency. Here we determine from first-principles the effects of temperature on the band gap and band edges of the hybrid pervoskite CH 3 NH 3 PbI 3 by accounting for electron-phonon coupling and thermal expansion. From 290 to 380 K, the computed band gap change of 40 meV coincides with the experimental change of 30-40 meV. The calculation of electron-phonon coupling in CH 3 NH 3 PbI 3 is particularly intricate as the commonly used Allen-Heine-Cardona theory overestimates the band gap change with temperature, and excellent agreement with experiment is only obtained when including high-order terms in the electron-phonon interaction. We also find that spin-orbit coupling enhances the electron-phonon coupling strength but that the inclusion of nonlocal correlations using hybrid functionals has little effect. We reach similar conclusions in the metal-halide perovskite CsPbI 3 . Our results unambiguously confirm for the first time the importance of high-order terms in the electron-phonon coupling by direct comparison with experiment.

  13. Optically transparent, scratch-resistant, diamond-like carbon coatings

    DOEpatents

    He, Xiao-Ming; Lee, Deok-Hyung; Nastasi, Michael A.; Walter, Kevin C.; Tuszewski, Michel G.

    2003-06-03

    A plasma-based method for the deposition of diamond-like carbon (DLC) coatings is described. The process uses a radio-frequency inductively coupled discharge to generate a plasma at relatively low gas pressures. The deposition process is environmentally friendly and scaleable to large areas, and components that have geometrically complicated surfaces can be processed. The method has been used to deposit adherent 100-400 nm thick DLC coatings on metals, glass, and polymers. These coatings are between three and four times harder than steel and are therefore scratch resistant, and transparent to visible light. Boron and silicon doping of the DLC coatings have produced coatings having improved optical properties and lower coating stress levels, but with slightly lower hardness.

  14. Production of Nitrous Oxide from Nitrite in Stable Type II Methanotrophic Enrichments.

    PubMed

    Myung, Jaewook; Wang, Zhiyue; Yuan, Tong; Zhang, Ping; Van Nostrand, Joy D; Zhou, Jizhong; Criddle, Craig S

    2015-09-15

    The coupled aerobic-anoxic nitrous decomposition operation is a new process for wastewater treatment that removes nitrogen from wastewater and recovers energy from the nitrogen in three steps: (1) NH4(+) oxidation to NO2(-), (2) NO2(-) reduction to N2O, and (3) N2O conversion to N2 with energy production. Here, we demonstrate that type II methanotrophic enrichments can mediate step two by coupling oxidation of poly(3-hydroxybutyrate) (P3HB) to NO2(-) reduction. Enrichments grown with NH4(+) and NO2(-) were subject to alternating 48-h aerobic and anoxic periods, in which CH4 and NO2(-) were added together in a "coupled" mode of operation or separately in a "decoupled mode". Community structure was stable in both modes and dominated by Methylocystis. In the coupled mode, production of P3HB and N2O was low. In the decoupled mode, significant P3HB was produced, and oxidation of P3HB drove reduction of NO2(-) to N2O with ∼ 70% conversion for >30 cycles (120 d). In batch tests of wasted cells from the decoupled mode, N2O production rates increased at low O2 or high NO2(-) levels. The results are significant for the development of engineered processes that remove nitrogen from wastewater and for understanding of conditions that favor environmental production of N2O.

  15. Evidence of weak land-atmosphere coupling under varying bare soil conditions: Are fully coupled Darcy/Navier-Stokes models necessary for simulating soil moisture dynamics?

    NASA Astrophysics Data System (ADS)

    Illangasekare, T. H.; Trautz, A. C.; Howington, S. E.; Cihan, A.

    2017-12-01

    It is a well-established fact that the land and atmosphere form a continuum in which the individual domains are coupled by heat and mass transfer processes such as bare-soil evaporation. Soil moisture dynamics can be simulated at the representative elementary volume (REV) scale using decoupled and fully coupled Darcy/Navier-Stokes models. Decoupled modeling is an asynchronous approach in which flow and transport in the soil and atmosphere is simulated independently; the two domains are coupled out of time-step via prescribed flux parameterizations. Fully coupled modeling in contrast, solves the governing equations for flow and transport in both domains simultaneously with the use of coupling interface boundary conditions. This latter approach, while being able to provide real-time two-dimensional feedbacks, is considerably more complex and computationally intensive. In this study, we investigate whether fully coupled models are necessary, or if the simpler decoupled models can sufficiently capture soil moisture dynamics under varying land preparations. A series of intermediate-scale physical and numerical experiments were conducted in which soil moisture distributions and evaporation estimates were monitored at high spatiotemporal resolutions for different heterogeneous packing and soil roughness scenarios. All experimentation was conducted at the newly developed Center for Experimental Study of Subsurface Environmental Processes (CESEP) wind tunnel-porous media user test-facility at the Colorado School of. Near-surface atmospheric measurements made during the experiments demonstrate that the land-atmosphere coupling was relatively weak and insensitive to the applied edaphic and surface conditions. Simulations with a decoupled multiphase heat and mass transfer model similarly show little sensitivity to local variations in atmospheric forcing; a single, simple flux parameterization can sufficiently capture the soil moisture dynamics (evaporation and redistribution) as long as the subsurface conditions (i.e., heterogeneity) are properly described. These findings suggest that significant improvements to simulations results should not be expected if fully coupled modeling were adopted in scenarios of weak land-atmosphere coupling in the context of bare soil evaporation.

  16. Cost Benefit Analysis of Integrated COTS Energy- Related Technologies for Army’s Force Provider Module

    DTIC Science & Technology

    2009-09-01

    Year Defense Plan (FYDP), on which the Department of Defense operates, subsequently needs 26 Richard G. Lugar, U.S. Senator for Indiana , “U.S...mature thin-film technologies exist such as Amorphous Silicon (a-Si), Cadmium Telluride (CdTe), and Copper Indium Gallium (di) Selenide (CIGS), all...cheaper processing, lower material costs, and is free of the environmental and health hazard issues of cadmium . Amorphous silicon coupled with

  17. Fresh insight to functioning of selected enzymes of the nitrogen cycle.

    PubMed

    Eady, Robert R; Antonyuk, Svetlana V; Hasnain, S Samar

    2016-04-01

    The global nitrogen cycle is the process in which different forms of environmental N are interconverted by microorganisms either for assimilation into biomass or in respiratory energy-generating pathways. This short review highlights developments over the last 5 years in our understanding of functionality of nitrogenase, Cu-nitrite reductase, NO reductase and N2O reductase, complex metalloenzymes that catalyze electron/proton-coupled substrate reduction reactions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Biogeochemical redox processes and their impact on contaminant dynamics

    USGS Publications Warehouse

    Borch, Thomas; Kretzschmar, Ruben; Kappler, Andreas; Van Cappellen, Philippe; Ginder-Vogel, Matthew; Campbell, Kate M.

    2010-01-01

    Life and element cycling on Earth is directly related to electron transfer (or redox) reactions. An understanding of biogeochemical redox processes is crucial for predicting and protecting environmental health and can provide new opportunities for engineered remediation strategies. Energy can be released and stored by means of redox reactions via the oxidation of labile organic carbon or inorganic compounds (electron donors) by microorganisms coupled to the reduction of electron acceptors including humic substances, iron-bearing minerals, transition metals, metalloids, and actinides. Environmental redox processes play key roles in the formation and dissolution of mineral phases. Redox cycling of naturally occurring trace elements and their host minerals often controls the release or sequestration of inorganic contaminants. Redox processes control the chemical speciation, bioavailability, toxicity, and mobility of many major and trace elements including Fe, Mn, C, P, N, S, Cr, Cu, Co, As, Sb, Se, Hg, Tc, and U. Redox-active humic substances and mineral surfaces can catalyze the redox transformation and degradation of organic contaminants. In this review article, we highlight recent advances in our understanding of biogeochemical redox processes and their impact on contaminant fate and transport, including future research needs.

  19. Aeolian and fluvial processes in dryland regions: the need for integrated studies

    USGS Publications Warehouse

    Belnap, Jayne; Munson, Seth M.; Field, Jason P.

    2011-01-01

    Aeolian and fluvial processes play a fundamental role in dryland regions of the world and have important environmental and ecological consequences from local to global scales. Although both processes operate over similar spatial and temporal scales and are likely strongly coupled in many dryland systems, aeolian and fluvial processes have traditionally been studied separately, making it difficult to assess their relative importance in drylands, as well as their potential for synergistic interaction. Land degradation by accelerated wind and water erosion is a major problem throughout the world's drylands, and although recent studies suggest that these processes likely interact across broad spatial and temporal scales to amplify the transport of soil resources from and within drylands, many researchers and land managers continue to view them as separate and unrelated processes. Here, we illustrate how aeolian and fluvial sediment transport is coupled at multiple spatial and temporal scales and highlight the need for these interrelated processes to be studied from a more integrated perspective that crosses traditional disciplinary boundaries. Special attention is given to how the growing threat of climate change and land-use disturbance will influence linkages between aeolian and fluvial processes in the future. We also present emerging directions for interdisciplinary needs within the aeolian and fluvial research communities that call for better integration across a broad range of traditional disciplines such as ecology, biogeochemistry, agronomy, and soil conservation.

  20. Optimization and application of fabric phase sorptive extraction coupled to ultra-high performance liquid chromatography tandem mass spectrometry for the determination of cytostatic drug residues in environmental waters.

    PubMed

    Santana-Viera, Sergio; Guedes-Alonso, Rayco; Sosa-Ferrera, Zoraida; Santana-Rodríguez, José Juan; Kabir, Abuzar; Furton, Kenneth G

    2017-12-22

    Every year, hundreds of tons of organic pollutants reach the environment through effluents released from wastewater treatment plants worldwide, and many of these compounds have harmful effects on the aquatic ecosystem. A new class of emerging pollutants of high concern is cytostatic drugs, which are designed to treat different types of cancers by attacking cells. Environmental concentrations of cytostatic drugs are known to be in the range of ngL -1 , and for this reason, it is imperative to develop analytical methods of extraction and preconcentration to allow for subsequent instrumental analysis of these drugs. In this work, a rapid, simple and green method for the analysis of seven cytostatic drug compounds that are commonly used in anti-cancer therapies was developed using a novel extraction process based on a powerful miniaturized technique, fabric phase sorptive extraction (FPSE) coupled to ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The major parameters that affect the extraction process were optimized. The new method shows good linearity, with a relative standard deviation (RSD) of less than 12%. Relative recoveries higher than 40% were obtained for the studied compounds, and the detection limit of the method was within the values at which these compounds are usually found in environmental water (0.20ngL -1 to 80ngL -1 ). The Limit of Quantification ranged from 0.68 to 267ngL -1 . Significant suppression of the signal due to the matrix effect, a common shortcoming attributed to interference from the extraction process as well as the use of ionization mode, was not observed. Subsequently, the method was applied to real wastewater samples from an effluent obtained from a hospital area and three wastewater treatment plants located in Gran Canaria Island, Spain. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Data discovery and data processing for environmental research infrastructures

    NASA Astrophysics Data System (ADS)

    Los, Wouter; Beranzoli, Laura; Corriero, Giuseppe; Cossu, Roberto; Fiore, Nicola; Hardisty, Alex; Legré, Yannick; Pagano, Pasquale; Puglisi, Giuseppe; Sorvari, Sanna; Turunen, Esa

    2013-04-01

    The European ENVRI project (Common operations of Environmental Research Infrastructures) is addressing common ICT solutions for the research infrastructures as selected in the ESFRI Roadmap. More specifically, the project is looking for solutions that will assist interdisciplinary users who want to benefit from the data and other services of more than a single research infrastructure. However, the infrastructure architectures, the data, data formats, scales and granularity are very different. Indeed, they deal with diverse scientific disciplines, from plate tectonics, the deep sea, sea and land surface up to atmosphere and troposphere, from the dead to the living environment, and with a variety of instruments producing increasingly larger amounts of data. One of the approaches in the ENVRI project is to design a common Reference Model that will serve to promote infrastructure interoperability at the data, technical and service levels. The analysis of the characteristics of the environmental research infrastructures assisted in developing the Reference Model, and which is also an example for comparable infrastructures worldwide. Still, it is for users already now important to have the facilities available for multi-disciplinary data discovery and data processing. The rise of systems research, addressing Earth as a single complex and coupled system is requiring such capabilities. So, another approach in the project is to adapt existing ICT solutions to short term applications. This is being tested for a few study cases. One of these is looking for possible coupled processes following a volcano eruption in the vertical column from deep sea to troposphere. Another one deals with volcano either human impacts on atmospheric and sea CO2 pressure and the implications for sea acidification and marine biodiversity and their ecosystems. And a third one deals with the variety of sensor and satellites data sensing the area around a volcano cone. Preliminary results on these studies will be reported. The common results will assist in shaping more generic solutions to be adopted by the appropriate research infrastructures.

  2. Risk assessment and adaptive runoff utilization in water resource system considering the complex relationship among water supply, electricity generation and environment

    NASA Astrophysics Data System (ADS)

    Zhou, J.; Zeng, X.; Mo, L.; Chen, L.; Jiang, Z.; Feng, Z.; Yuan, L.; He, Z.

    2017-12-01

    Generally, the adaptive utilization and regulation of runoff in the source region of China's southwest rivers is classified as a typical multi-objective collaborative optimization problem. There are grim competitions and incidence relation in the subsystems of water supply, electricity generation and environment, which leads to a series of complex problems represented by hydrological process variation, blocked electricity output and water environment risk. Mathematically, the difficulties of multi-objective collaborative optimization focus on the description of reciprocal relationships and the establishment of evolving model of adaptive systems. Thus, based on the theory of complex systems science, this project tries to carry out the research from the following aspects: the changing trend of coupled water resource, the covariant factor and driving mechanism, the dynamic evolution law of mutual feedback dynamic process in the supply-generation-environment coupled system, the environmental response and influence mechanism of coupled mutual feedback water resource system, the relationship between leading risk factor and multiple risk based on evolutionary stability and dynamic balance, the transfer mechanism of multiple risk response with the variation of the leading risk factor, the multidimensional coupled feedback system of multiple risk assessment index system and optimized decision theory. Based on the above-mentioned research results, the dynamic method balancing the efficiency of multiple objectives in the coupled feedback system and optimized regulation model of water resources is proposed, and the adaptive scheduling mode considering the internal characteristics and external response of coupled mutual feedback system of water resource is established. In this way, the project can make a contribution to the optimal scheduling theory and methodology of water resource management under uncertainty in the source region of Southwest River.

  3. Shared Genetics and Couple-Associated Environment Are Major Contributors to the Risk of Both Clinical and Self-Declared Depression.

    PubMed

    Zeng, Yanni; Navarro, Pau; Xia, Charley; Amador, Carmen; Fernandez-Pujals, Ana M; Thomson, Pippa A; Campbell, Archie; Nagy, Reka; Clarke, Toni-Kim; Hafferty, Jonathan D; Smith, Blair H; Hocking, Lynne J; Padmanabhan, Sandosh; Hayward, Caroline; MacIntyre, Donald J; Porteous, David J; Haley, Chris S; McIntosh, Andrew M

    2016-12-01

    Both genetic and environmental factors contribute to risk of depression, but estimates of their relative contributions are limited. Commonalities between clinically-assessed major depressive disorder (MDD) and self-declared depression (SDD) are also unclear. Using data from a large Scottish family-based cohort (GS:SFHS, N=19,994), we estimated the genetic and environmental variance components for MDD and SDD. The components representing the genetic effect associated with genome-wide common genetic variants (SNP heritability), the additional pedigree-associated genetic effect and non-genetic effects associated with common environments were estimated in a linear mixed model (LMM). Both MDD and SDD had significant contributions from components representing the effect from common genetic variants, the additional genetic effect associated with the pedigree and the common environmental effect shared by couples. The estimate of correlation between SDD and MDD was high (r=1.00, se=0.20) for common-variant-associated genetic effect and lower for the additional genetic effect from the pedigree (r=0.57, se=0.08) and the couple-shared environmental effect (r=0.53, se=0.22). Both genetics and couple-shared environmental effects were major factors influencing liability to depression. SDD may provide a scalable alternative to MDD in studies seeking to identify common risk variants. Rarer variants and environmental effects may however differ substantially according to different definitions of depression. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  4. A central role for the retrosplenial cortex in de novo environmental learning

    PubMed Central

    Auger, Stephen D; Zeidman, Peter; Maguire, Eleanor A

    2015-01-01

    With experience we become accustomed to the types of environments that we normally encounter as we navigate in the world. But how does this fundamental knowledge develop in the first place and what brain regions are involved? To examine de novo environmental learning, we created an ‘alien’ virtual reality world populated with landmarks of which participants had no prior experience. They learned about this environment by moving within it during functional MRI (fMRI) scanning while we tracked their evolving knowledge. Retrosplenial cortex (RSC) played a central and highly selective role by representing only the most stable, permanent features in this world. Subsequently, increased coupling was noted between RSC and hippocampus, with hippocampus then expressing knowledge of permanent landmark locations and overall environmental layout. Studying how environmental representations emerge from scratch provided a new window into the information processing underpinning the brain's navigation system, highlighting the key influence of the RSC. DOI: http://dx.doi.org/10.7554/eLife.09031.001 PMID:26284602

  5. Coupling Recruitment Forecasts with Economics in the Gulf of Maine's American Lobster Fishery

    NASA Astrophysics Data System (ADS)

    Wahle, R.; Oppenheim, N.; Brady, D. C.; Dayton, A.; Sun, C. H. J.

    2016-02-01

    Accurate predictions of fishery recruitment and landings represent an important goal of fisheries science and management, but linking environmental drivers of fish population dynamics to financial markets remains a challenge. A fundamental step in that process is understanding the environmental drivers of fishery recruitment. American lobster (Homarus americanus) populations of the northwest Atlantic have been undergoing a dramatic surge, mostly driven by increases the Gulf of Maine. Settler-recruit models that track cohorts after larvae settle to the sea bed are proving useful in predicting subsequent fishery recruitment some 5-7 years later. Here we describe new recruitment forecasting models for the lobster fishery at 11 management areas from Southern New England to Atlantic Canada. We use an annual survey of juvenile year-class strength and environmental indicators to parameterize growth and mortality terms in the model. As a consequence of a recent widespread multi-year downturn in larval settlement, our models suggest that the peak in lobster abundance in the Gulf of Maine will be passed in the near future. We also present initial steps in the coupling of forecast data with economic models for the fishery. We anticipate that these models will give stakeholders and policy makers time to consider their management choices for this most valuable of the region's fisheries. Our vision is to couple our forecast model outputs to an economic model that captures the dynamics of market forces in the New England and Canadian Maritime lobster fisheries. It will then be possible to estimate the financial status of the fishery several years in advance. This early warning system could mitigate the adverse effects of a fluctuating fishery on the coastal communities that are perilously dependent upon it.

  6. Look@NanoSIMS--a tool for the analysis of nanoSIMS data in environmental microbiology.

    PubMed

    Polerecky, Lubos; Adam, Birgit; Milucka, Jana; Musat, Niculina; Vagner, Tomas; Kuypers, Marcel M M

    2012-04-01

    We describe an open-source freeware programme for high throughput analysis of nanoSIMS (nanometre-scale secondary ion mass spectrometry) data. The programme implements basic data processing and analytical functions, including display and drift-corrected accumulation of scanned planes, interactive and semi-automated definition of regions of interest (ROIs), and export of the ROIs' elemental and isotopic composition in graphical and text-based formats. Additionally, the programme offers new functions that were custom-designed to address the needs of environmental microbiologists. Specifically, it allows manual and automated classification of ROIs based on the information that is derived either from the nanoSIMS dataset itself (e.g. from labelling achieved by halogen in situ hybridization) or is provided externally (e.g. as a fluorescence in situ hybridization image). Moreover, by implementing post-processing routines coupled to built-in statistical tools, the programme allows rapid synthesis and comparative analysis of results from many different datasets. After validation of the programme, we illustrate how these new processing and analytical functions increase flexibility, efficiency and depth of the nanoSIMS data analysis. Through its custom-made and open-source design, the programme provides an efficient, reliable and easily expandable tool that can help a growing community of environmental microbiologists and researchers from other disciplines process and analyse their nanoSIMS data. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  7. The GeoDataPortal: A Standards-based Environmental Modeling Data Access and Manipulation Toolkit

    NASA Astrophysics Data System (ADS)

    Blodgett, D. L.; Kunicki, T.; Booth, N.; Suftin, I.; Zoerb, R.; Walker, J.

    2010-12-01

    Environmental modelers from fields of study such as climatology, hydrology, geology, and ecology rely on many data sources and processing methods that are common across these disciplines. Interest in inter-disciplinary, loosely coupled modeling and data sharing is increasing among scientists from the USGS, other agencies, and academia. For example, hydrologic modelers need downscaled climate change scenarios and land cover data summarized for the watersheds they are modeling. Subsequently, ecological modelers are interested in soil moisture information for a particular habitat type as predicted by the hydrologic modeler. The USGS Center for Integrated Data Analytics Geo Data Portal (GDP) project seeks to facilitate this loose model coupling data sharing through broadly applicable open-source web processing services. These services simplify and streamline the time consuming and resource intensive tasks that are barriers to inter-disciplinary collaboration. The GDP framework includes a catalog describing projects, models, data, processes, and how they relate. Using newly introduced data, or sources already known to the catalog, the GDP facilitates access to sub-sets and common derivatives of data in numerous formats on disparate web servers. The GDP performs many of the critical functions needed to summarize data sources into modeling units regardless of scale or volume. A user can specify their analysis zones or modeling units as an Open Geospatial Consortium (OGC) standard Web Feature Service (WFS). Utilities to cache Shapefiles and other common GIS input formats have been developed to aid in making the geometry available for processing via WFS. Dataset access in the GDP relies primarily on the Unidata NetCDF-Java library’s common data model. Data transfer relies on methods provided by Unidata’s Thematic Real-time Environmental Data Distribution System Data Server (TDS). TDS services of interest include the Open-source Project for a Network Data Access Protocol (OPeNDAP) standard for gridded time series, the OGC’s Web Coverage Service for high-density static gridded data, and Unidata’s CDM-remote for point time series. OGC WFS and Sensor Observation Service (SOS) are being explored as mechanisms to serve and access static or time series data attributed to vector geometry. A set of standardized XML-based output formats allows easy transformation into a wide variety of “model-ready” formats. Interested users will have the option of submitting custom transformations to the GDP or transforming the XML output as a post-process. The GDP project aims to support simple, rapid development of thin user interfaces (like web portals) to commonly needed environmental modeling-related data access and manipulation tools. Standalone, service-oriented components of the GDP framework provide the metadata cataloging, data subset access, and spatial-statistics calculations needed to support interdisciplinary environmental modeling.

  8. Coupled Environmental Processes in the Mojave Desert and Implications for ET Covers as Stable Landforms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    D. Shafer; M. Y oung; S. Zitzer

    2006-01-18

    Monolayer evapotranspiration (ET) covers are the baseline method for closure of disposal sites for low-level radioactive waste (LLW), mixed LLW, and transuranic (TRU) waste at the Nevada Test Site (NTS). The regulatory timeline is typically 1,000 years for LLW and 10,000 years for TRU waste. Covers for such waste have different technical considerations than those with shorter timelines because they are subject to environmental change for longer periods of time, and because the environmental processes are often coupled. To evaluate these changes, four analog sites (approximately 30, 1,000 to 2,000, 7,000 to 12,500, and 125,000 years in age) on themore » NTS were analyzed to address the early post-institutional control period (the youngest site), the 1,000-year compliance period for disposal of LLW, and the 10,000-year period for TRU waste. Tests included soil texture, structure, and morphology; surface soil infiltration and hydraulic conductivity; vegetation and faunal surveys; and literature reviews. Separate measurements were made in plant undercanopy and intercanopy areas. The results showed a progressive increase in silt and clay content of surface soils with age. Changes in soil texture and structure led to a fivefold decline in saturated hydraulic conductivity in intercanopy areas, but no change in undercanopies, which were subject to bioturbation. These changes may have been responsible for the reduction in total plant cover, most dramatically in intercanopy areas, primarily because more precipitation either runs off the site or is held nearer to the surface where plant roots are less common. The results suggest that covers may evolve over longer timeframes to stable landforms that minimize the need for active maintenance.« less

  9. Microenvironmental change as a mechanism to study global change.

    NASA Astrophysics Data System (ADS)

    Lortie, C. J.

    2016-12-01

    Global change is a set of significant processes that influence all aspects of ecosystem functioning and often-natural services within Santa Barbara County. The sensitivity of coastal and urban systems is certainly very high. However, profound changes are also predicted for arid and semi-arid systems globally, and California is no exception. These dryland systems are less buffered by oceanic processes and typically express high inter-annual variation in precipitation and temperatures in addition to perturbations associated with long-term droughts. However, climate estimates and downscaled values can present challenges in providing evidence at the scale relevant to individual species or individuals, and the importance of biotic interactions must be coupled to these estimates in space and time. Coupled indicators of key micro-environmental measures to both positive and negative interactions between foundation species and other organisms provide a metric of buffering capacity and resilience to global change at fine spatial scales. Consequently, the primary objective of this research project is to provide both the a well-articulated, ecologically relevant micro-environmental big data measure of global change within Santa Barbara County and a coupled estimate of concurrent changes in interactions in key species within the region. Shrubs directly and indirectly buffered local changes in the microenvironment thereby functioning as refuges for other species within arid and semi-arid regions subject to dramatic global change drivers. The following major patterns were identified: (i) shrub micro-environments reduce the level of stress and amplitude of variation associated with temperature and moisture, (ii) many plant and animal species including threatened lizards are relatively more common with shrubs within the region, and (iii) the variation in the interaction patterns between species relates to the extent of amelioration provided by shrub-biodiversity complexes within the region. The ecological theory of positive plant interactions scaling to other species as a restoration and management tool is a dominant and rapidly evolving field of research. Micro-environmental sensor arrays are a scientifically valid approach to identify meaningful localized change with biotic interactions.

  10. A wind-powered BDD electrochemical oxidation process for the removal of herbicides.

    PubMed

    Souza, F L; Lanza, M R V; Llanos, J; Sáez, C; Rodrigo, M A; Cañizares, P

    2015-08-01

    In the search for greener treatment technologies, this work studies the coupling of a wind turbine energy supply with an electrolytic cell (CWTEC device) for the remediation of wastewater polluted with pesticide 2,4-dichlorophenoxyacetic acid (2,4-D). The discontinuous and unforeseeable supply of energy is the main challenge inspiring this new proposal, which aims at reducing the environmental impact of electrolytic treatment by using a green energy supply. The results obtained using the coupled technologies are compared with those obtained by powering the electrolyser with a traditional power supply with a similar current intensity. The mineralisation of wastewater can be accomplished independently of how the electrolytic cell is powered, although differences in performance are clearly observed in the total organic carbon (TOC) and 2,4-D decays. These changes can be explained in terms of the changing profile of the current intensity, which influences the concentrations of the oxidants produced and thereby the mediated electrolytic process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Hydrological and geomorphological controls of malaria transmission

    NASA Astrophysics Data System (ADS)

    Smith, M. W.; Macklin, M. G.; Thomas, C. J.

    2013-01-01

    Malaria risk is linked inextricably to the hydrological and geomorphological processes that form vector breeding sites. Yet environmental controls of malaria transmission are often represented by temperature and rainfall amounts, ignoring hydrological and geomorphological influences altogether. Continental-scale studies incorporate hydrology implicitly through simple minimum rainfall thresholds, while community-scale coupled hydrological and entomological models do not represent the actual diversity of the mosquito vector breeding sites. The greatest range of malaria transmission responses to environmental factors is observed at the catchment scale where seemingly contradictory associations between rainfall and malaria risk can be explained by hydrological and geomorphological processes that govern surface water body formation and persistence. This paper extends recent efforts to incorporate ecological factors into malaria-risk models, proposing that the same detailed representation be afforded to hydrological and, at longer timescales relevant for predictions of climate change impacts, geomorphological processes. We review existing representations of environmental controls of malaria and identify a range of hydrologically distinct vector breeding sites from existing literature. We illustrate the potential complexity of interactions among hydrology, geomorphology and vector breeding sites by classifying a range of water bodies observed in a catchment in East Africa. Crucially, the mechanisms driving surface water body formation and destruction must be considered explicitly if we are to produce dynamic spatial models of malaria risk at catchment scales.

  12. Effect of Freeze-Thaw Cycles on Soil Nitrogen Reactive Transport in a Polygonal Arctic Tundra Ecosystem at Barrow AK Using 3-D Coupled ALM-PFLOTRAN

    NASA Astrophysics Data System (ADS)

    Yuan, F.; Wang, G.; Painter, S. L.; Tang, G.; Xu, X.; Kumar, J.; Bisht, G.; Hammond, G. E.; Mills, R. T.; Thornton, P. E.; Wullschleger, S. D.

    2017-12-01

    In Arctic tundra ecosystem soil freezing-thawing is one of dominant physical processes through which biogeochemical (e.g., carbon and nitrogen) cycles are tightly coupled. Besides hydraulic transport, freezing-thawing can cause pore water movement and aqueous species gradients, which are additional mechanisms for soil nitrogen (N) reactive-transport in Tundra ecosystem. In this study, we have fully coupled an in-development ESM(i.e., Advanced Climate Model for Energy, ACME)'s Land Model (ALM) aboveground processes with a state-of-the-art massively parallel 3-D subsurface thermal-hydrology and reactive transport code, PFLOTRAN. The resulting coupled ALM-PFLOTRAN model is a Land Surface Model (LSM) capable of resolving 3-D soil thermal-hydrological-biogeochemical cycles. This specific version of PFLOTRAN has incorporated CLM-CN Converging Trophic Cascade (CTC) model and a full and simple but robust soil N cycle. It includes absorption-desorption for soil NH4+ and gas dissolving-degasing process as well. It also implements thermal-hydrology mode codes with three newly-modified freezing-thawing algorithms which can greatly improve computing performance in regarding to numerical stiffness at freezing-point. Here we tested the model in fully 3-D coupled mode at the Next Generation Ecosystem Experiment-Arctic (NGEE-Arctic) field intensive study site at the Barrow Environmental Observatory (BEO), AK. The simulations show that: (1) synchronous coupling of soil thermal-hydrology and biogeochemistry in 3-D can greatly impact ecosystem dynamics across polygonal tundra landscape; and (2) freezing-thawing cycles can add more complexity to the system, resulting in greater mobility of soil N vertically and laterally, depending upon local micro-topography. As a preliminary experiment, the model is also implemented for Pan-Arctic region in 1-D column mode (i.e. no lateral connection), showing significant differences compared to stand-alone ALM. The developed ALM-PFLOTRAN coupling codes embeded within ESM will be used for Pan-Arctic regional evaluation of climate change-caused ecosystem responses and their feedbacks to climate system at various scales.

  13. Decision support for environmental management of industrial non-hazardous secondary materials: New analytical methods combined with simulation and optimization modeling.

    PubMed

    Little, Keith W; Koralegedara, Nadeesha H; Northeim, Coleen M; Al-Abed, Souhail R

    2017-07-01

    Non-hazardous solid materials from industrial processes, once regarded as waste and disposed in landfills, offer numerous environmental and economic advantages when put to beneficial uses (BUs). Proper management of these industrial non-hazardous secondary materials (INSM) requires estimates of their probable environmental impacts among disposal as well as BU options. The U.S. Environmental Protection Agency (EPA) has recently approved new analytical methods (EPA Methods 1313-1316) to assess leachability of constituents of potential concern in these materials. These new methods are more realistic for many disposal and BU options than historical methods, such as the toxicity characteristic leaching protocol. Experimental data from these new methods are used to parameterize a chemical fate and transport (F&T) model to simulate long-term environmental releases from flue gas desulfurization gypsum (FGDG) when disposed of in an industrial landfill or beneficially used as an agricultural soil amendment. The F&T model is also coupled with optimization algorithms, the Beneficial Use Decision Support System (BUDSS), under development by EPA to enhance INSM management. Published by Elsevier Ltd.

  14. Environmental requirements for flat plate photovoltaic modules for terrestrial applications

    NASA Technical Reports Server (NTRS)

    Hoffman, A. R.; Ross, R. G., Jr.

    1979-01-01

    The environmental test requirements that have been developed for flat plate modules purchased through Department of Energy funding are described. Concurrent with the selection of the initial qualification tests from space program experience - temperature cycling and humidity - surveys of existing photovoltaic systems in the field revealed that arrays were experiencing the following failure modes: interconnect breakage, delamination, and electrical termination corrosion. These coupled with application-dependent considerations led to the development of additional qualification tests, such as cyclic pressure loading, warped mounting surface, and hail. Rationale for the selection of tests, their levels and durations is described. Comparisons between field-observed degradation and test-induced degradation show a positive correlation with some of the observed field effects. Also, the tests are proving useful for detecting design, process, and workmanship deficiencies. The status of study efforts for the development of environmental requirements for field-related problems is reviewed.

  15. Using a spatially-distributed hydrologic biogeochemistry model with a nitrogen transport module to study the spatial variation of carbon processes in a Critical Zone Observatory

    DOE PAGES

    Shi, Yuning; Eissenstat, David M.; He, Yuting; ...

    2018-05-12

    Terrestrial carbon processes are affected by soil moisture, soil temperature, nitrogen availability and solar radiation, among other factors. Most of the current ecosystem biogeochemistry models represent one point in space, and have limited characterization of hydrologic processes. Therefore these models can neither resolve the topographically driven spatial variability of water, energy, and nutrient, nor their effects on carbon processes. A spatially-distributed land surface hydrologic biogeochemistry model, Flux-PIHM-BGC, is developed by coupling the Biome-BGC model with a physically-based land surface hydrologic model, Flux-PIHM. In the coupled system, each Flux-PIHM model grid couples a 1-D Biome-BGC model. In addition, a topographic solarmore » radiation module and an advection-driven nitrogen transport module are added to represent the impact of topography on nutrient transport and solar energy distribution. Because Flux-PIHM is able to simulate lateral groundwater flow and represent the land surface heterogeneities caused by topography, Flux-PIHM-BGC is capable of simulating the complex interaction among water, energy, nutrient, and carbon in time and space. The Flux-PIHM-BGC model is tested at the Susquehanna/Shale Hills Critical Zone Observatory. Model results show that distributions of carbon and nitrogen stocks and fluxes are strongly affected by topography and landscape position, and tree growth is nitrogen limited. The predicted aboveground and soil carbon distributions generally agree with the macro patterns observed. Although the model underestimates the spatial variation, the predicted watershed average values are close to the observations. Lastly, the coupled Flux-PIHM-BGC model provides an important tool to study spatial variations in terrestrial carbon and nitrogen processes and their interactions with environmental factors, and to predict the spatial structure of the responses of ecosystems to climate change.« less

  16. Using a spatially-distributed hydrologic biogeochemistry model with a nitrogen transport module to study the spatial variation of carbon processes in a Critical Zone Observatory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shi, Yuning; Eissenstat, David M.; He, Yuting

    Terrestrial carbon processes are affected by soil moisture, soil temperature, nitrogen availability and solar radiation, among other factors. Most of the current ecosystem biogeochemistry models represent one point in space, and have limited characterization of hydrologic processes. Therefore these models can neither resolve the topographically driven spatial variability of water, energy, and nutrient, nor their effects on carbon processes. A spatially-distributed land surface hydrologic biogeochemistry model, Flux-PIHM-BGC, is developed by coupling the Biome-BGC model with a physically-based land surface hydrologic model, Flux-PIHM. In the coupled system, each Flux-PIHM model grid couples a 1-D Biome-BGC model. In addition, a topographic solarmore » radiation module and an advection-driven nitrogen transport module are added to represent the impact of topography on nutrient transport and solar energy distribution. Because Flux-PIHM is able to simulate lateral groundwater flow and represent the land surface heterogeneities caused by topography, Flux-PIHM-BGC is capable of simulating the complex interaction among water, energy, nutrient, and carbon in time and space. The Flux-PIHM-BGC model is tested at the Susquehanna/Shale Hills Critical Zone Observatory. Model results show that distributions of carbon and nitrogen stocks and fluxes are strongly affected by topography and landscape position, and tree growth is nitrogen limited. The predicted aboveground and soil carbon distributions generally agree with the macro patterns observed. Although the model underestimates the spatial variation, the predicted watershed average values are close to the observations. Lastly, the coupled Flux-PIHM-BGC model provides an important tool to study spatial variations in terrestrial carbon and nitrogen processes and their interactions with environmental factors, and to predict the spatial structure of the responses of ecosystems to climate change.« less

  17. Online Coupling of Flow-Field Flow Fractionation and Single Particle Inductively Coupled Plasma-Mass Spectrometry: Characterization of Nanoparticle Surface Coating Thickness and Aggregation State

    EPA Science Inventory

    Surface coating thickness and aggregation state have strong influence on the environmental fate, transport, and toxicity of engineered nanomaterials. In this study, flow-field flow fractionation coupled on-line with single particle inductively coupled plasma-mass spectrometry i...

  18. Development of capability for microtopography-resolving simulations of hydrologic processes in permafrost affected regions

    NASA Astrophysics Data System (ADS)

    Painter, S.; Moulton, J. D.; Berndt, M.; Coon, E.; Garimella, R.; Lewis, K. C.; Manzini, G.; Mishra, P.; Travis, B. J.; Wilson, C. J.

    2012-12-01

    The frozen soils of the Arctic and subarctic regions contain vast amounts of stored organic carbon. This carbon is vulnerable to release to the atmosphere as temperatures warm and permafrost degrades. Understanding the response of the subsurface and surface hydrologic system to degrading permafrost is key to understanding the rate, timing, and chemical form of potential carbon releases to the atmosphere. Simulating the hydrologic system in degrading permafrost regions is challenging because of the potential for topographic evolution and associated drainage network reorganization as permafrost thaws and massive ground ice melts. The critical process models required for simulating hydrology include subsurface thermal hydrology of freezing/thawing soils, thermal processes within ice wedges, mechanical deformation processes, overland flow, and surface energy balances including snow dynamics. A new simulation tool, the Arctic Terrestrial Simulator (ATS), is being developed to simulate these coupled processes. The computational infrastructure must accommodate fully unstructured grids that track evolving topography, allow accurate solutions on distorted grids, provide robust and efficient solutions on highly parallel computer architectures, and enable flexibility in the strategies for coupling among the various processes. The ATS is based on Amanzi (Moulton et al. 2012), an object-oriented multi-process simulator written in C++ that provides much of the necessary computational infrastructure. Status and plans for the ATS including major hydrologic process models and validation strategies will be presented. Highly parallel simulations of overland flow using high-resolution digital elevation maps of polygonal patterned ground landscapes demonstrate the feasibility of the approach. Simulations coupling three-phase subsurface thermal hydrology with a simple thaw-induced subsidence model illustrate the strong feedbacks among the processes. D. Moulton, M. Berndt, M. Day, J. Meza, et al., High-Level Design of Amanzi, the Multi-Process High Performance Computing Simulator, Technical Report ASCEM-HPC-2011-03-1, DOE Environmental Management, 2012.

  19. Science with society in the anthropocene.

    PubMed

    Seidl, Roman; Brand, Fridolin Simon; Stauffacher, Michael; Krütli, Pius; Le, Quang Bao; Spörri, Andy; Meylan, Grégoire; Moser, Corinne; González, Monica Berger; Scholz, Roland Werner

    2013-02-01

    Interdisciplinary scientific knowledge is necessary but not sufficient when it comes to addressing sustainable transformations, as science increasingly has to deal with normative and value-related issues. A systems perspective on coupled human-environmental systems (HES) helps to address the inherent complexities. Additionally, a thorough interaction between science and society (i.e., transdisciplinarity = TD) is necessary, as sustainable transitions are sometimes contested and can cause conflicts. In order to navigate complexities regarding the delicate interaction of scientific research with societal decisions these processes must proceed in a structured and functional way. We thus propose HES-based TD processes to provide a basis for reorganizing science in coming decades.

  20. Biochemomechanical poroelastic theory of avascular tumor growth

    NASA Astrophysics Data System (ADS)

    Xue, Shi-Lei; Li, Bo; Feng, Xi-Qiao; Gao, Huajian

    2016-09-01

    Tumor growth is a complex process involving genetic mutations, biochemical regulations, and mechanical deformations. In this paper, a thermodynamics-based nonlinear poroelastic theory is established to model the coupling among the mechanical, chemical, and biological mechanisms governing avascular tumor growth. A volumetric growth law accounting for mechano-chemo-biological coupled effects is proposed to describe the development of solid tumors. The regulating roles of stresses and nutrient transport in the tumor growth are revealed under different environmental constraints. We show that the mechano-chemo-biological coupling triggers anisotropic and heterogeneous growth, leading to the formation of layered structures in a growing tumor. There exists a steady state in which tumor growth is balanced by resorption. The influence of external confinements on tumor growth is also examined. A phase diagram is constructed to illustrate how the elastic modulus and thickness of the confinements jointly dictate the steady state of tumor volume. Qualitative and quantitative agreements with experimental observations indicate the developed model is capable of capturing the essential features of avascular tumor growth in various environments.

  1. International Conference/Workshop on Small Fatigue Cracks (2nd) Held in Santa Barbara, California on 5-10 January 1986.

    DTIC Science & Technology

    1986-03-31

    critical issues thus pertain to the determination of crack tip conditions, as a function of crack length, in terms of the coupled processes of fluid...transport and chemical/electrochemical reactions within the crack, and the determination of the origin of the environmentally-enhanced cracking rates in...Depth in Determining Crack Electrochemistry and Crack Growth" A. Turnbull, National Physical Laboratory, U.K., and R. C. Newmann, UMIST, U.K. 7:30 p.m.-7

  2. Worldwide Emerging Environmental Issues Affecting the U.S. Military. January 2007 Report

    DTIC Science & Technology

    2007-01-01

    Appendix) 6.3 New Technique for DNA Isolation TNO, in Delft, Netherlands, has developed a new tool, SamPrep, for the rapid automatic pre- treatment of...manual processing of the same task takes up to six hours. TNO has focused initially on detecting Legionella to demonstrate how powerful the SamPrep...Within a couple of hours it is evident whether the water is contaminated with Legionella . The system also works for other bacteria, such as hospital and

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cournia, Zoe; Allen, Toby W.; Andricioaei, Ioan

    It is fundamental for the flourishing biological cells that membrane proteins mediate the process. Membrane-embedded transporters move ions and larger solutes across membranes; receptors mediate communication between the cell and its environment and membrane-embedded enzymes catalyze chemical reactions. Understanding these mechanisms of action requires knowledge of how the proteins couple to their fluid, hydrated lipid membrane environment. Here, we present here current studies in computational and experimental membrane protein biophysics, and show how they address outstanding challenges in understanding the complex environmental effects on the structure, function, and dynamics of membrane proteins.

  4. Operationalizing the social-ecological systems framework to assess sustainability.

    PubMed

    Leslie, Heather M; Basurto, Xavier; Nenadovic, Mateja; Sievanen, Leila; Cavanaugh, Kyle C; Cota-Nieto, Juan José; Erisman, Brad E; Finkbeiner, Elena; Hinojosa-Arango, Gustavo; Moreno-Báez, Marcia; Nagavarapu, Sriniketh; Reddy, Sheila M W; Sánchez-Rodríguez, Alexandra; Siegel, Katherine; Ulibarria-Valenzuela, José Juan; Weaver, Amy Hudson; Aburto-Oropeza, Octavio

    2015-05-12

    Environmental governance is more effective when the scales of ecological processes are well matched with the human institutions charged with managing human-environment interactions. The social-ecological systems (SESs) framework provides guidance on how to assess the social and ecological dimensions that contribute to sustainable resource use and management, but rarely if ever has been operationalized for multiple localities in a spatially explicit, quantitative manner. Here, we use the case of small-scale fisheries in Baja California Sur, Mexico, to identify distinct SES regions and test key aspects of coupled SESs theory. Regions that exhibit greater potential for social-ecological sustainability in one dimension do not necessarily exhibit it in others, highlighting the importance of integrative, coupled system analyses when implementing spatial planning and other ecosystem-based strategies.

  5. Compact high reliability fiber coupled laser diodes for avionics and related applications

    NASA Astrophysics Data System (ADS)

    Daniel, David R.; Richards, Gordon S.; Janssen, Adrian P.; Turley, Stephen E. H.; Stockton, Thomas E.

    1993-04-01

    This paper describes a newly developed compact high reliability fiber coupled laser diode which is capable of providing enhanced performance under extreme environmental conditions including a very wide operating temperature range. Careful choice of package materials to minimize thermal and mechanical stress, used with proven manufacturing methods, has resulted in highly stable coupling of the optical fiber pigtail to a high performance MOCVD-grown Multi-Quantum Well laser chip. Electro-optical characteristics over temperature are described together with a demonstration of device stability over a range of environmental conditions. Real time device lifetime data is also presented.

  6. Coupling of diversification and pH adaptation during the evolution of terrestrial Thaumarchaeota.

    PubMed

    Gubry-Rangin, Cécile; Kratsch, Christina; Williams, Tom A; McHardy, Alice C; Embley, T Martin; Prosser, James I; Macqueen, Daniel J

    2015-07-28

    The Thaumarchaeota is an abundant and ubiquitous phylum of archaea that plays a major role in the global nitrogen cycle. Previous analyses of the ammonia monooxygenase gene amoA suggest that pH is an important driver of niche specialization in these organisms. Although the ecological distribution and ecophysiology of extant Thaumarchaeota have been studied extensively, the evolutionary rise of these prokaryotes to ecological dominance in many habitats remains poorly understood. To characterize processes leading to their diversification, we investigated coevolutionary relationships between amoA, a conserved marker gene for Thaumarchaeota, and soil characteristics, by using deep sequencing and comprehensive environmental data in Bayesian comparative phylogenetics. These analyses reveal a large and rapid increase in diversification rates during early thaumarchaeotal evolution; this finding was verified by independent analyses of 16S rRNA. Our findings suggest that the entire Thaumarchaeota diversification regime was strikingly coupled to pH adaptation but less clearly correlated with several other tested environmental factors. Interestingly, the early radiation event coincided with a period of pH adaptation that enabled the terrestrial Thaumarchaeota ancestor to initially move from neutral to more acidic and alkaline conditions. In contrast to classic evolutionary models, whereby niches become rapidly filled after adaptive radiation, global diversification rates have remained stably high in Thaumarchaeota during the past 400-700 million years, suggesting an ongoing high rate of niche formation or switching for these microbes. Our study highlights the enduring importance of environmental adaptation during thaumarchaeotal evolution and, to our knowledge, is the first to link evolutionary diversification to environmental adaptation in a prokaryotic phylum.

  7. Coupling of diversification and pH adaptation during the evolution of terrestrial Thaumarchaeota

    PubMed Central

    Gubry-Rangin, Cécile; Kratsch, Christina; Williams, Tom A.; McHardy, Alice C.; Embley, T. Martin; Prosser, James I.; Macqueen, Daniel J.

    2015-01-01

    The Thaumarchaeota is an abundant and ubiquitous phylum of archaea that plays a major role in the global nitrogen cycle. Previous analyses of the ammonia monooxygenase gene amoA suggest that pH is an important driver of niche specialization in these organisms. Although the ecological distribution and ecophysiology of extant Thaumarchaeota have been studied extensively, the evolutionary rise of these prokaryotes to ecological dominance in many habitats remains poorly understood. To characterize processes leading to their diversification, we investigated coevolutionary relationships between amoA, a conserved marker gene for Thaumarchaeota, and soil characteristics, by using deep sequencing and comprehensive environmental data in Bayesian comparative phylogenetics. These analyses reveal a large and rapid increase in diversification rates during early thaumarchaeotal evolution; this finding was verified by independent analyses of 16S rRNA. Our findings suggest that the entire Thaumarchaeota diversification regime was strikingly coupled to pH adaptation but less clearly correlated with several other tested environmental factors. Interestingly, the early radiation event coincided with a period of pH adaptation that enabled the terrestrial Thaumarchaeota ancestor to initially move from neutral to more acidic and alkaline conditions. In contrast to classic evolutionary models, whereby niches become rapidly filled after adaptive radiation, global diversification rates have remained stably high in Thaumarchaeota during the past 400–700 million years, suggesting an ongoing high rate of niche formation or switching for these microbes. Our study highlights the enduring importance of environmental adaptation during thaumarchaeotal evolution and, to our knowledge, is the first to link evolutionary diversification to environmental adaptation in a prokaryotic phylum. PMID:26170282

  8. A Solution Framework for Environmental Characterization Problems

    EPA Science Inventory

    This paper describes experiences developing a grid-enabled framework for solving environmental inverse problems. The solution approach taken here couples environmental simulation models with global search methods and requires readily available computational resources of the grid ...

  9. Multi-Directional Environmental Sensors

    NASA Technical Reports Server (NTRS)

    Manohara, Harish (Inventor); Del Castillo, Linda Y. (Inventor); Mojarradi, Mohammed M. (Inventor)

    2016-01-01

    Systems and methods in accordance with embodiments of the invention implement multi-directional environmental sensors. In one embodiment, a multi-directional environmental sensor includes: an inner conductive element that is substantially symmetrical about three orthogonal planes; an outer conductive element that is substantially symmetrical about three orthogonal planes; and a device that measures the electrical characteristics of the multi-directional environmental sensor, the device having a first terminal and a second terminal; where the inner conductive element is substantially enclosed within the outer conductive element; where the inner conductive element is electrically coupled to the first terminal of the device; and where the outer conductive element is electrically coupled to the second terminal of the device.

  10. Socio-hydrologic modeling to understand and mediate the competition for water between agriculture development and environmental health: Murrumbidgee River Basin, Australia

    NASA Astrophysics Data System (ADS)

    van Emmerik, T. H. M.; Li, Z.; Sivapalan, M.; Pande, S.; Kandasamy, J.; Savenije, H. H. G.; Chanan, A.; Vigneswaran, S.

    2014-03-01

    Competition for water between humans and ecosystems is set to become a flash point in the coming decades in many parts of the world. An entirely new and comprehensive quantitative framework is needed to establish a holistic understanding of that competition, thereby enabling the development of effective mediation strategies. This paper presents a modeling study centered on the Murrumbidgee River Basin (MRB). The MRB has witnessed a unique system dynamics over the last 100 years as a result of interactions between patterns of water management and climate driven hydrological variability. Data analysis has revealed a pendulum swing between agricultural development and restoration of environmental health and ecosystem services over different stages of basin scale water resource development. A parsimonious, stylized, quasi-distributed coupled socio-hydrologic system model that simulates the two-way coupling between human and hydrological systems of the MRB is used to mimic dominant features of the pendulum swing. The model consists of coupled nonlinear ordinary differential equations that describe the interaction between five state variables that govern the co-evolution: reservoir storage, irrigated area, human population, ecosystem health, and a measure of environmental awareness. The model simulations track the propagation of the external climatic and socio-economic drivers through this coupled, complex system to the emergence of the pendulum swing. The model results point to a competition between human "productive" and environmental "restorative" forces that underpin the pendulum swing. Both the forces are endogenous, i.e., generated by the system dynamics in response to external drivers and mediated by humans through technology change and environmental awareness, respectively. We propose this as a generalizable modeling framework for coupled human hydrological systems that is potentially transferable to systems in different climatic and socio-economic settings.

  11. Development of the Hydroecological Integrity Assessment Process for Determining Environmental Flows for New Jersey Streams

    USGS Publications Warehouse

    Kennen, Jonathan G.; Henriksen, James A.; Nieswand, Steven P.

    2007-01-01

    The natural flow regime paradigm and parallel stream ecological concepts and theories have established the benefits of maintaining or restoring the full range of natural hydrologic variation for physiochemical processes, biodiversity, and the evolutionary potential of aquatic and riparian communities. A synthesis of recent advances in hydroecological research coupled with stream classification has resulted in a new process to determine environmental flows and assess hydrologic alteration. This process has national and international applicability. It allows classification of streams into hydrologic stream classes and identification of a set of non-redundant and ecologically relevant hydrologic indices for 10 critical sub-components of flow. Three computer programs have been developed for implementing the Hydroecological Integrity Assessment Process (HIP): (1) the Hydrologic Indices Tool (HIT), which calculates 171 ecologically relevant hydrologic indices on the basis of daily-flow and peak-flow stream-gage data; (2) the New Jersey Hydrologic Assessment Tool (NJHAT), which can be used to establish a hydrologic baseline period, provide options for setting baseline environmental-flow standards, and compare past and proposed streamflow alterations; and (3) the New Jersey Stream Classification Tool (NJSCT), designed for placing unclassified streams into pre-defined stream classes. Biological and multivariate response models including principal-component, cluster, and discriminant-function analyses aided in the development of software and implementation of the HIP for New Jersey. A pilot effort is currently underway by the New Jersey Department of Environmental Protection in which the HIP is being used to evaluate the effects of past and proposed surface-water use, ground-water extraction, and land-use changes on stream ecosystems while determining the most effective way to integrate the process into ongoing regulatory programs. Ultimately, this scientifically defensible process will help to quantify the effects of anthropogenic changes and development on hydrologic variability and help planners and resource managers balance current and future water requirements with ecological needs.

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adam, J. C.; Stephens, J. C.; Chung, Serena

    As managers of agricultural and natural resources are confronted with uncertainties in global change impacts, the complexities associated with the interconnected cycling of nitrogen, carbon, and water present daunting management challenges. Existing models provide detailed information on specific sub-systems (land, air, water, economics, etc). An increasing awareness of the unintended consequences of management decisions resulting from interconnectedness of these sub-systems, however, necessitates coupled regional earth system models (EaSMs). Decision makers’ needs and priorities can be integrated into the model design and development processes to enhance decision-making relevance and "usability" of EaSMs. BioEarth is a current research initiative with a focusmore » on the U.S. Pacific Northwest region that explores the coupling of multiple stand-alone EaSMs to generate usable information for resource decision-making. Direct engagement between model developers and non-academic stakeholders involved in resource and environmental management decisions throughout the model development process is a critical component of this effort. BioEarth utilizes a "bottom-up" approach, upscaling a catchment-scale model to basin and regional scales, as opposed to the "top-down" approach of downscaling global models utilized by most other EaSM efforts. This paper describes the BioEarth initiative and highlights opportunities and challenges associated with coupling multiple stand-alone models to generate usable information for agricultural and natural resource decision-making.« less

  13. A study of Ground Source Heat Pump based on a heat infiltrates coupling model established with FEFLOW

    NASA Astrophysics Data System (ADS)

    Chen, H.; Hu, C.; Chen, G.; Zhang, Q.

    2017-12-01

    Geothermal heat is a viable source of energy and its environmental impact in terms of CO2 emissions is significantly lower than conventional fossil fuels. it is vital that engineers acquire a proper understanding about the Ground Source Heat Pump (GSHP). In this study, the model of the borehole exchanger under conduction manners and heat infiltrates coupling manners was established with FEFLOW. The energy efficiency, heat transfer endurance and heat transfer in the unit depth were introduced to quantify the energy efficient and the endurance period. The performance of a the Borehole Exchanger (BHE) in soil with and without groundwater seepage was analyzed of heat transfer process between the soil and the working fluid. Basing on the model, the varied regularity of energy efficiency performance an heat transfer endurance with the conditions including the different configuration of the BHE, the soil properties, thermal load characteristic were discussed. Focus on the heat transfer process in multi-layer soil which one layer exist groundwater flow. And an investigation about thermal dispersivity was also analyzed its influence on heat transfer performance. The final result proves that the model of heat infiltrates coupling model established in this context is reasonable, which can be applied to engineering design.

  14. Time-series modeling and prediction of global monthly absolute temperature for environmental decision making

    NASA Astrophysics Data System (ADS)

    Ye, Liming; Yang, Guixia; Van Ranst, Eric; Tang, Huajun

    2013-03-01

    A generalized, structural, time series modeling framework was developed to analyze the monthly records of absolute surface temperature, one of the most important environmental parameters, using a deterministicstochastic combined (DSC) approach. Although the development of the framework was based on the characterization of the variation patterns of a global dataset, the methodology could be applied to any monthly absolute temperature record. Deterministic processes were used to characterize the variation patterns of the global trend and the cyclic oscillations of the temperature signal, involving polynomial functions and the Fourier method, respectively, while stochastic processes were employed to account for any remaining patterns in the temperature signal, involving seasonal autoregressive integrated moving average (SARIMA) models. A prediction of the monthly global surface temperature during the second decade of the 21st century using the DSC model shows that the global temperature will likely continue to rise at twice the average rate of the past 150 years. The evaluation of prediction accuracy shows that DSC models perform systematically well against selected models of other authors, suggesting that DSC models, when coupled with other ecoenvironmental models, can be used as a supplemental tool for short-term (˜10-year) environmental planning and decision making.

  15. A Coupled Multiphysics Approach for Simulating Induced Seismicity, Ground Acceleration and Structural Damage

    NASA Astrophysics Data System (ADS)

    Podgorney, Robert; Coleman, Justin; Wilkins, Amdrew; Huang, Hai; Veeraraghavan, Swetha; Xia, Yidong; Permann, Cody

    2017-04-01

    Numerical modeling has played an important role in understanding the behavior of coupled subsurface thermal-hydro-mechanical (THM) processes associated with a number of energy and environmental applications since as early as the 1970s. While the ability to rigorously describe all key tightly coupled controlling physics still remains a challenge, there have been significant advances in recent decades. These advances are related primarily to the exponential growth of computational power, the development of more accurate equations of state, improvements in the ability to represent heterogeneity and reservoir geometry, and more robust nonlinear solution schemes. The work described in this paper documents the development and linkage of several fully-coupled and fully-implicit modeling tools. These tools simulate: (1) the dynamics of fluid flow, heat transport, and quasi-static rock mechanics; (2) seismic wave propagation from the sources of energy release through heterogeneous material; and (3) the soil-structural damage resulting from ground acceleration. These tools are developed in Idaho National Laboratory's parallel Multiphysics Object Oriented Simulation Environment, and are integrated together using a global implicit approach. The governing equations are presented, the numerical approach for simultaneously solving and coupling the three coupling physics tools is discussed, and the data input and output methodology is outlined. An example is presented to demonstrate the capabilities of the coupled multiphysics approach. The example involves simulating a system conceptually similar to the geothermal development in Basel Switzerland, and the resultant induced seismicity, ground motion and structural damage is predicted.

  16. Saliency Detection as a Reactive Process: Unexpected Sensory Events Evoke Corticomuscular Coupling

    PubMed Central

    Kilintari, Marina; Srinivasan, Mandayam; Haggard, Patrick

    2018-01-01

    Survival in a fast-changing environment requires animals not only to detect unexpected sensory events, but also to react. In humans, these salient sensory events generate large electrocortical responses, which have been traditionally interpreted within the sensory domain. Here we describe a basic physiological mechanism coupling saliency-related cortical responses with motor output. In four experiments conducted on 70 healthy participants, we show that salient substartle sensory stimuli modulate isometric force exertion by human participants, and that this modulation is tightly coupled with electrocortical activity elicited by the same stimuli. We obtained four main results. First, the force modulation follows a complex triphasic pattern consisting of alternating decreases and increases of force, time-locked to stimulus onset. Second, this modulation occurs regardless of the sensory modality of the eliciting stimulus. Third, the magnitude of the force modulation is predicted by the amplitude of the electrocortical activity elicited by the same stimuli. Fourth, both neural and motor effects are not reflexive but depend on contextual factors. Together, these results indicate that sudden environmental stimuli have an immediate effect on motor processing, through a tight corticomuscular coupling. These observations suggest that saliency detection is not merely perceptive but reactive, preparing the animal for subsequent appropriate actions. SIGNIFICANCE STATEMENT Salient events occurring in the environment, regardless of their modalities, elicit large electrical brain responses, dominated by a widespread “vertex” negative-positive potential. This response is the largest synchronization of neural activity that can be recorded from a healthy human being. Current interpretations assume that this vertex potential reflects sensory processes. Contrary to this general assumption, we show that the vertex potential is strongly coupled with a modulation of muscular activity that follows the same pattern. Both the vertex potential and its motor effects are not reflexive but strongly depend on contextual factors. These results reconceptualize the significance of these evoked electrocortical responses, suggesting that saliency detection is not merely perceptive but reactive, preparing the animal for subsequent appropriate actions. PMID:29378865

  17. Quantum coherence and entanglement control for atom-cavity systems

    NASA Astrophysics Data System (ADS)

    Shu, Wenchong

    Coherence and entanglement play a significant role in the quantum theory. Ideal quantum systems, "closed" to the outside world, remain quantum forever and thus manage to retain coherence and entanglement. Real quantum systems, however, are open to the environment and are therefore susceptible to the phenomenon of decoherence and disentanglement which are major hindrances to the effectiveness of quantum information processing tasks. In this thesis we have theoretically studied the evolution of coherence and entanglement in quantum systems coupled to various environments. We have also studied ways and means of controlling the decay of coherence and entanglement. We have studied the exact qubit entanglement dynamics of some interesting initial states coupled to a high-Q cavity containing zero photon, one photon, two photons and many photons respectively. We have found that an initially correlated environmental state can serve as an enhancer for entanglement decay or generation processes. More precisely, we have demonstrated that the degree of entanglement, including its collapse as well as its revival times, can be significantly modified by the correlated structure of the environmental modes. We have also studied dynamical decoupling (DD) technique --- a prominent strategy of controlling decoherence and preserving entanglement in open quantum systems. We have analyzed several DD control methods applied to qubit systems that can eliminate the system-environment coupling and prolong the quantum coherence time. Particularly, we have proposed a new DD sequence consisting a set of designed control operators that can universally protected an unknown qutrit state against colored phase and amplitude environment noises. In addition, in a non-Markovian regime, we have reformulated the quantum state diffusion (QSD) equation to incorporate the effect of the external control fields. Without any assumptions on the system-environment coupling and the size of environment, we have consistently solved the control dynamics of open quantum systems using this stochastic QSD approach. By implementing the QSD equation, our numerical results have revealed that how the control efficacy depends on the designed time points and shapes of the applied control pulses, and the environment memory time scale.

  18. Toward Process-resolving Synthesis and Prediction of Arctic Climate Change Using the Regional Arctic System Model

    NASA Astrophysics Data System (ADS)

    Maslowski, W.

    2017-12-01

    The Regional Arctic System Model (RASM) has been developed to better understand the operation of Arctic System at process scale and to improve prediction of its change at a spectrum of time scales. RASM is a pan-Arctic, fully coupled ice-ocean-atmosphere-land model with marine biogeochemistry extension to the ocean and sea ice models. The main goal of our research is to advance a system-level understanding of critical processes and feedbacks in the Arctic and their links with the Earth System. The secondary, an equally important objective, is to identify model needs for new or additional observations to better understand such processes and to help constrain models. Finally, RASM has been used to produce sea ice forecasts for September 2016 and 2017, in contribution to the Sea Ice Outlook of the Sea Ice Prediction Network. Future RASM forecasts, are likely to include increased resolution for model components and ecosystem predictions. Such research is in direct support of the US environmental assessment and prediction needs, including those of the U.S. Navy, Department of Defense, and the recent IARPC Arctic Research Plan 2017-2021. In addition to an overview of RASM technical details, selected model results are presented from a hierarchy of climate models together with available observations in the region to better understand potential oceanic contributions to polar amplification. RASM simulations are analyzed to evaluate model skill in representing seasonal climatology as well as interannual and multi-decadal climate variability and predictions. Selected physical processes and resulting feedbacks are discussed to emphasize the need for fully coupled climate model simulations, high model resolution and sensitivity of simulated sea ice states to scale dependent model parameterizations controlling ice dynamics, thermodynamics and coupling with the atmosphere and ocean.

  19. Integrating Geomorphic and Social Dynamics in the Analysis of Anthropogenic Landforms: Examining Landscape Evolution of Terrain Modified by Agricultural Terracing

    NASA Astrophysics Data System (ADS)

    Glaubius, J.; Maerker, M.

    2016-12-01

    Anthropogenic landforms, such as mines and agricultural terraces, are impacted by both geomorphic and social processes at varying intensities through time. In the case of agricultural terraces, decisions regarding terrace maintenance are intertwined with land use, such as when terraced fields are abandoned. Furthermore, terrace maintenance and land use decisions, either jointly or separately, may be in response to geomorphic processes, as well as geomorphic feedbacks. Previous studies of these complex geomorphic systems considered agricultural terraces as static features or analyzed only the geomorphic response to landowner decisions. Such research is appropriate for short-term or binary landscape scenarios (e.g. the impact of maintained vs. abandoned terraces), but the complexities inherent in these socio-natural systems requires an approach that includes both social and geomorphic processes. This project analyzes feedbacks and emergent properties in terraced systems by implementing a coupled landscape evolution model (LEM) and agent-based model (ABM) using the Landlab and Mesa modeling libraries. In the ABM portion of the model, agricultural terraces are conceptualized using a life-cycle stages schema and implemented using Markov Decision Processes to simulate the changing geomorphic impact of terracing based on human decisions. This paper examines the applicability of this approach by comparing results from a LEM-only model against the coupled LEM-ABM model for a terraced region. Model results are compared by quantify and spatial patterning of sediment transport. This approach fully captures long-term landscape evolution of terraced terrain that is otherwise lost when the life-cycle of terraces is not considered. The coupled LEM-ABM approach balances both environmental and social processes so that the socio-natural feedbacks in such anthropogenic systems can be disentangled.

  20. Earth orbital variations and vertebrate bioevolution

    NASA Technical Reports Server (NTRS)

    Mclean, Dewey M.

    1988-01-01

    Cause of the Pleistocene-Holocene transition mammalian extinctions at the end of the last age is the subject of debate between those advocating human predation and climate change. Identification of an ambient air temperature (AAT)-uterine blood flow (UBF) coupling phenomenon supports climate change as a factor in the extinctions, and couples the extinctions to earth orbital variations that drive ice age climatology. The AAT-UBF phenomenon couples mammalian bioevolution directly to climate change via effects of environmental heat upon blood flow to the female uterus and damage to developing embryos. Extinctions were in progress during climatic warming before the Younger Dryas event, and after, at times when the AAT-UBF couple would have been operative; however, impact of a sudden short-term cooling on mammals in the process of adapting to smaller size and relatively larger S/V would have been severe. Variations in earth's orbit, and orbital forcing of atmospheric CO2 concentrations, were causes of the succession of Pleistocene ice ages. Coincidence of mammalian extinctions with terminations of the more intense cold stages links mammalian bioevolution to variations in earth's orbit. Earth orbital variations are a driving source of vertebrate bioevolution.

  1. Respiration of Nitrate and Nitrite.

    PubMed

    Cole, Jeffrey A; Richardson, David J

    2008-09-01

    Nitrate reduction to ammonia via nitrite occurs widely as an anabolic process through which bacteria, archaea, and plants can assimilate nitrate into cellular biomass. Escherichia coli and related enteric bacteria can couple the eight-electron reduction of nitrate to ammonium to growth by coupling the nitrate and nitrite reductases involved to energy-conserving respiratory electron transport systems. In global terms, the respiratory reduction of nitrate to ammonium dominates nitrate and nitrite reduction in many electron-rich environments such as anoxic marine sediments and sulfide-rich thermal vents, the human gastrointestinal tract, and the bodies of warm-blooded animals. This review reviews the regulation and enzymology of this process in E. coli and, where relevant detail is available, also in Salmonella and draws comparisons with and implications for the process in other bacteria where it is pertinent to do so. Fatty acids may be present in high levels in many of the natural environments of E. coli and Salmonella in which oxygen is limited but nitrate is available to support respiration. In E. coli, nitrate reduction in the periplasm involves the products of two seven-gene operons, napFDAGHBC, encoding the periplasmic nitrate reductase, and nrfABCDEFG, encoding the periplasmic nitrite reductase. No bacterium has yet been shown to couple a periplasmic nitrate reductase solely to the cytoplasmic nitrite reductase NirB. The cytoplasmic pathway for nitrate reduction to ammonia is restricted almost exclusively to a few groups of facultative anaerobic bacteria that encounter high concentrations of environmental nitrate.

  2. Gas and liquid chromatography with inductively coupled plasma mass spectrometry detection for environmental speciation analysis — advances and limitations

    NASA Astrophysics Data System (ADS)

    Szpunar, Joanna; McSheehy, Shona; Połeć, Kasia; Vacchina, Véronique; Mounicou, Sandra; Rodriguez, Isaac; Łobiński, Ryszard

    2000-07-01

    Recent advances in the coupling of gas chromatography (GC) and high performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICP MS) and their role in trace element speciation analysis of environmental materials are presented. The discussion is illustrated with three research examples concerning the following topics: (i) development and coupling of multicapillary microcolumn GC with ICP MS for speciation of organotin in sediment and biological tissue samples; (ii) speciation of arsenic in marine algae by size-exclusion-anion-exchange HPLC-ICP MS; and (iii) speciation of cadmium in plant cell cultures by size-exclusion HPLC-ICP MS. Particular attention is paid to the problem of signal identification in ICP MS chromatograms; the potential of electrospray MS/MS for this purpose is highlighted.

  3. Exciton transport in the PE545 complex: insight from atomistic QM/MM-based quantum master equations and elastic network models

    NASA Astrophysics Data System (ADS)

    Pouyandeh, Sima; Iubini, Stefano; Jurinovich, Sandro; Omar, Yasser; Mennucci, Benedetta; Piazza, Francesco

    2017-12-01

    In this paper, we work out a parameterization of environmental noise within the Haken-Strobl-Reinenker (HSR) model for the PE545 light-harvesting complex, based on atomic-level quantum mechanics/molecular mechanics (QM/MM) simulations. We use this approach to investigate the role of various auto- and cross-correlations in the HSR noise tensor, confirming that site-energy autocorrelations (pure dephasing) terms dominate the noise-induced exciton mobility enhancement, followed by site energy-coupling cross-correlations for specific triplets of pigments. Interestingly, several cross-correlations of the latter kind, together with coupling-coupling cross-correlations, display clear low-frequency signatures in their spectral densities in the 30-70 cm-1 region. These slow components lie at the limits of validity of the HSR approach, which requires that environmental fluctuations be faster than typical exciton transfer time scales. We show that a simple coarse-grained elastic-network-model (ENM) analysis of the PE545 protein naturally spotlights collective normal modes in this frequency range that represent specific concerted motions of the subnetwork of cysteines covalenty linked to the pigments. This analysis strongly suggests that protein scaffolds in light-harvesting complexes are able to express specific collective, low-frequency normal modes providing a fold-rooted blueprint of exciton transport pathways. We speculate that ENM-based mixed quantum classical methods, such as Ehrenfest dynamics, might be promising tools to disentangle the fundamental designing principles of these dynamical processes in natural and artificial light-harvesting structures.

  4. Process-Property Relationship for Air Plasma-Sprayed Gadolinium Zirconate Coatings

    NASA Astrophysics Data System (ADS)

    Dwivedi, Gopal; Tan, Yang; Viswanathan, Vaishak; Sampath, Sanjay

    2015-02-01

    The continuous need of elevating operating temperature of gas turbine engines has introduced several challenges with the current state-of-the-art yttria-stabilized zirconia (YSZ)-based thermal barrier coatings (TBCs), requiring examination of new TBC material with high temperature phase stability, lower thermal conductivity, and resistance to environmental ash particles. Gadolinium zirconate (Gd2Zr2O7) (GDZ) has been shown to meet many of these requirements, and has, in fact, been successfully implemented in to engine components. However, several fundamental issues related to the process-ability, toughness, and microstructural differences for GDZ when compared to equivalent YSZ coating. This study seeks to critically address the process-structure-property correlations for plasma-sprayed GDZ coating subjected to controlled parametric exploration. Use of in-flight diagnostics coupled with in situ and ex situ coating property monitoring allows examination and comparison of the process-property interplay and the resultant differences between the two TBC compositions. The results indicate that it is feasible to retain material chemistry and fabricate relevant microstructures of interest with GDZ with concomitant performance advantages such as low conductivity, mechanical compliance, sintering resistance, and suppression of environmentally induced damage from ash particles. This study provides a framework for optimal design and manufacturing of emergent multi-layer and multi-material TBCs.

  5. Experimental observation of complete and anticipation synchronization of heterogeneous oscillators using a common dynamical environment

    NASA Astrophysics Data System (ADS)

    Singla, Tanu; Chandrasekhar, E.; Singh, B. P.; Parmananda, P.

    2014-12-01

    Complete and anticipation synchronization of nonlinear oscillators from different origins is attempted experimentally. This involves coupling these heterogeneous oscillators to a common dynamical environment. Initially, this phenomenon was studied using two parameter mismatched Chua circuits. Subsequently, three different timeseries: a) x variable of the Lorenz oscillator b) the X-component of Earth's magnetic field and c) per-day temperature variation of the Region Santa Cruz in Mumbai, India are environmentally coupled, under the master-slave scenario, with a Chua circuit. Our results indicate that environmental coupling is a potent tool to provoke complete and anticipation synchronization of heterogeneous oscillators from distinct origins.

  6. Environmental consequences of shale gas exploitation and the crucial role of rock microfracturing

    NASA Astrophysics Data System (ADS)

    Renard, Francois

    2015-04-01

    The growing exploitation of unconventional gas and oil resources has dramatically changed the international market of hydrocarbons in the past ten years. However, several environmental concerns have also been identified such as the increased microseismicity, the leakage of gas into freshwater aquifers, and the enhanced water-rock interactions inducing the release of heavy metals and other toxic elements in the produced water. In all these processes, fluids are transported into a network of fracture, ranging from nanoscale microcracks at the interface between minerals and the kerogen of the source rock, to well-developed fractures at the meter scale. Characterizing the fracture network and the mechanisms of its formation remains a crucial goal. A major difficulty when analyzing fractures from core samples drilled at depth is that some of them are produced by the coring process, while some other are produced naturally at depth by the coupling between geochemical and mechanical forces. Here, I present new results of high resolution synchrotron 3D X-ray microtomography imaging of shale samples, at different resolutions, to characterize their microfractures and their mechanisms of formation. The heterogeneities of rock microstructure are also imaged, as they create local stress concentrations where cracks may nucleate or along which they propagate. The main results are that microcracks form preferentially along kerogen-mineral interfaces and propagate along initial heterogeneities according to the local stress direction, connecting to increase the total volume of fractured rock. Their lifetime is also an important parameter because they may seal by fluid circulation, fluid-rock interactions, and precipitation of a cement. Understanding the multi-scale processes of fracture network development in shales and the coupling with fluid circulation represents a key challenge for future research directions.

  7. A New Method for Estimation of Emissions and Sources of Measurements Error in the Silicon Refining Process

    NASA Astrophysics Data System (ADS)

    Næss, Mari k.; Kero, Ida; Tranell, Gabriella

    2013-08-01

    In the production of metallurgical grade silicon (MG-Si), fugitive emissions are a serious concern due to the health risks associated with the fumes formed in different parts of the production. The fumes are also a potential environmental hazard. Yet, the chemical composition of the fumes from most process steps in the silicon plant, such as oxidative refining ladle, remains unknown. This in turn constitutes a problem with respect to the correct assessment of the environmental impact and working conditions. A comprehensive industrial measurement campaign was performed at the Elkem Salten MG-Si production plant in Norway. Samples of the ingoing and outgoing mass flows were analyzed by high-resolution inductively coupled plasma mass spectrometry, with respect to 62 elements. In every step of the sampling and sample treatment processes, possible sources of error have been identified and quantified, including process variation, mass measurement accuracy, and contamination risk. Total measurement errors for all elements in all phases are established. The method is applied to estimate the order of magnitude of the elemental emissions via the fumes from the tapping and refining processes, with respect to production mass and year. The elements with higher concentrations in the fume than slag and refined silicon include Ag, Bi, Cd, Cu, In, K, Mg, Na, Pb, Rb, Se, Sn, Tl, and Zn: all being present in the ppm range. This work constitutes new and vital information to enable the correct assessment of the environmental impact and working conditions at an MG-Si plant.

  8. Recoupling Industrial Dairy Feedlots and Industrial Farmlands Mitigates the Environmental Impacts of Milk Production in China.

    PubMed

    Fan, Xing; Chang, Jie; Ren, Yuan; Wu, Xu; Du, Yuanyuan; Xu, Ronghua; Liu, Dong; Chang, Scott X; Meyerson, Laura A; Peng, Changhui; Ge, Ying

    2018-04-03

    Dairy production is becoming more industrialized globally, especially in developing countries. The large amount of animal wastes from industrial feedlots cannot be fully used on nearby farmlands, leading to severe environmental problems. Using China as a case study, we found that most dairy feedlots employ a semicoupled mode that only recycles solid manure to farmlands, and only a few dairy feedlots employ a fully coupled mode that recycles both solid and liquid animal manure. To produce 1 ton of milk, the fully coupled mode could reduce greenhouse gas (including carbon dioxide, methane, and nitrous oxide in this paper) emissions by 24%, ammonia emissions by 14%, and N discharge into water by 29%, compared with the semicoupled systems. Coupling feedlots with constructed wetlands can further result in greater mitigation of N leaching into groundwater. However, the fully coupled system has not been widely used due to the low benefit to farmers and the institutional barrier that the feedlot owners have no right to use adjacent farmlands. Since a fully coupled system improves net ecosystem services that favor the public, a policy that supports removing the economic and institutional barriers is necessary. Our approach provides a template for mitigating environmental impacts from livestock production without sacrificing milk production.

  9. Artificial Synaptic Devices Based on Natural Chicken Albumen Coupled Electric-Double-Layer Transistors

    NASA Astrophysics Data System (ADS)

    Wu, Guodong; Feng, Ping; Wan, Xiang; Zhu, Liqiang; Shi, Yi; Wan, Qing

    2016-03-01

    Recent progress in using biomaterials to fabricate functional electronics has got growing attention for the new generation of environmentally friendly and biocompatible electronic devices. As a kind of biological material with rich source, proteins are essential natural component of all organisms. At the same time, artificial synaptic devices are of great significance for neuromorphic systems because they can emulate the signal process and memory behaviors of biological synapses. In this report, natural chicken albumen with high proton conductivity was used as the coupling electrolyte film for organic/inorganic hybrid synaptic devices fabrication. Some important synaptic functions including paired-pulse facilitation, dynamic filtering, short-term to long-term memory transition and spatial summation and shunting inhibition were successfully mimicked. Our results are very interesting for biological friendly artificial neuron networks and neuromorphic systems.

  10. Development of a Three-Dimensional Spectral Element Model for NWP: Idealized Simulations on the Sphere

    NASA Astrophysics Data System (ADS)

    Viner, K.; Reinecke, P. A.; Gabersek, S.; Flagg, D. D.; Doyle, J. D.; Martini, M.; Ryglicki, D.; Michalakes, J.; Giraldo, F.

    2016-12-01

    NEPTUNE: the Navy Environmental Prediction sysTem Using the NUMA*corE, is a 3D spectral element atmospheric model composed of a full suite of physics parameterizations and pre- and post-processing infrastructure with plans for data assimilation and coupling components to a variety of Earth-system models. This talk will focus on the initial struggles and solutions in adapting NUMA for stable and accurate integration on the sphere using both the deep atmosphere equations and a newly developed shallow-atmosphere approximation, as demonstrated through idealized test cases. In addition, details of the physics-dynamics coupling methodology will be discussed. NEPTUNE results for test cases from the 2016 Dynamical Core Model Intercomparison Project (DCMIP-2016) will be shown and discussed. *NUMA: Nonhydrostatic Unified Model of the Atmosphere; Kelly and Giraldo 2012, JCP

  11. Hierarchy and Interactions in Environmental Interfaces Regarded as Biophysical Complex Systems

    NASA Astrophysics Data System (ADS)

    Mihailovic, Dragutin T.; Balaz, Igor

    The field of environmental sciences is abundant with various interfaces and is the right place for the application of new fundamental approaches leading towards a better understanding of environmental phenomena. For example, following the definition of environmental interface by Mihailovic and Balaž [23], such interface can be placed between: human or animal bodies and surrounding air, aquatic species and water and air around them, and natural or artificially built surfaces (vegetation, ice, snow, barren soil, water, urban communities) and the atmosphere. Complex environmental interface systems are open and hierarchically organised, interactions between their constituent parts are nonlinear, and the interaction with the surrounding environment is noisy. These systems are therefore very sensitive to initial conditions, deterministic external perturbations and random fluctuations always present in nature. The study of noisy non-equilibrium processes is fundamental for modelling the dynamics of environmental interface systems and for understanding the mechanisms of spatio-temporal pattern formation in contemporary environmental sciences, particularly in environmental fluid mechanics. In modelling complex biophysical systems one of the main tasks is to successfully create an operative interface with the external environment. It should provide a robust and prompt translation of the vast diversity of external physical and/or chemical changes into a set of signals, which are "understandable" for an organism. Although the establishment of organisation in any system is of crucial importance for its functioning, it should not be forgotten that in biophysical systems we deal with real-life problems where a number of other conditions should be reached in order to put the system to work. One of them is the proper supply of the system by the energy. Therefore, we will investigate an aspect of dynamics of energy flow based on the energy balance equation. The energy as well as the exchange of biological, chemical and other physical quantities between interacting environmental interfaces can be represented by coupled maps. In this chapter we will address only two illustrative issues important for the modelling of interacting environmental interfaces regarded as complex systems. These are (i) use of algebra for modelling the autonomous establishment of local hierarchies in biophysical systems and (ii) numerical investigation of coupled maps representing exchange of energy, chemical and other relevant biophysical quantities between biophysical entities in their surrounding environment.

  12. Mesoscopic modeling of multi-physicochemical transport phenomena in porous media

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kang, Qinjin; Wang, Moran; Mukherjee, Partha P

    2009-01-01

    We present our recent progress on mesoscopic modeling of multi-physicochemical transport phenomena in porous media based on the lattice Boltzmann method. Simulation examples include injection of CO{sub 2} saturated brine into a limestone rock, two-phase behavior and flooding phenomena in polymer electrolyte fuel cells, and electroosmosis in homogeneously charged porous media. It is shown that the lattice Boltzmann method can account for multiple, coupled physicochemical processes in these systems and can shed some light on the underlying physics occuning at the fundamental scale. Therefore, it can be a potential powerful numerical tool to analyze multi-physicochemical processes in various energy, earth,more » and environmental systems.« less

  13. Reanalyzing Environmental Lidar Data for Archaeology: Mesoamerican Applications and Implications

    NASA Technical Reports Server (NTRS)

    Golden, Charles; Murtha, Timothy; Cook, Bruce; Shaffer, Derek S.; Schroder, Whittaker; Hermitt, Elijah J.; Firpi, Omar Alcover; Scherer, Andrew K.

    2016-01-01

    This paper presents a preliminary archaeological assessment of extensive transects of lidar recently collected by environmental scientists over southern Mexico using the G-LiHT system of NASA's Goddard Space Flight Center. In particular, this article offers the results of a first phase of research, consisting of: 1) characterization and classification of the cultural and ecological context of the samples, and 2) bare earth processing and visual inspection of a sample of the flight paths for identification of probable anthropogenic Precolumbian features. These initial results demonstrate that significant contributions to understanding variations in Precolumbian land-use and settlement patterns and change is possible with truly multi-regional lidar surveys not originally captured for archaeological prospection. We point to future directions for the development of archaeological applications of this robust data set. Finally, we offer the potential for enriching archaeological research through tightly coupled collaborations with environmental science and monitoring. Archaeologists in the neotropics can acquire more data, better realize the full potential of lidar surveys, and better contribute to interdisciplinary studies of human-environmental dynamic systems through regionally focused and collaborative scientific research.

  14. Use of immunomagnetic separation for the detection of Desulfovibrio vulgaris from environmental samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chakraborty, R.; Hazen, T.C.; Joyner, D.C.

    2011-04-15

    Immunomagnetic separation (IMS) has proved highly efficient for recovering microorganisms from heterogeneous samples. Current investigation targeted the separation of viable cells of the sulfate-reducing bacterium, Desulfovibrio vulgaris. Streptavidin-coupled paramagnetic beads and biotin labeled antibodies raised against surface antigens of this microorganism were used to capture D. vulgaris cells in both bioreactor grown laboratory samples and from extremely low-biomass environmental soil and subsurface drilling samples. Initial studies on detection, recovery efficiency and viability for IMS were performed with laboratory grown D. vulgaris cells using various cell densities. Efficiency of cell isolation and recovery (i.e., release of the microbial cells from themore » beads following separation) was followed by microscopic imaging and acridine orange direct counts (AODC). Excellent recovery efficiency encouraged the use of IMS to capture Desulfovibrio spp. cells from low-biomass environmental samples. The environmental samples were obtained from a radionuclide-contaminated site in Germany and the chromium (VI)-contaminated Hanford site, an ongoing bioremediation project of the U.S. Department of Energy. Field deployable IMS technology may greatly facilitate environmental sampling and bioremediation process monitoring and enable transcriptomics and proteomics/metabolomics-based studies directly on cells collected from the field.« less

  15. Radiative transfer modeling through terrestrial atmosphere and ocean accounting for inelastic processes: Software package SCIATRAN

    NASA Astrophysics Data System (ADS)

    Rozanov, V. V.; Dinter, T.; Rozanov, A. V.; Wolanin, A.; Bracher, A.; Burrows, J. P.

    2017-06-01

    SCIATRAN is a comprehensive software package which is designed to model radiative transfer processes in the terrestrial atmosphere and ocean in the spectral range from the ultraviolet to the thermal infrared (0.18-40 μm). It accounts for multiple scattering processes, polarization, thermal emission and ocean-atmosphere coupling. The main goal of this paper is to present a recently developed version of SCIATRAN which takes into account accurately inelastic radiative processes in both the atmosphere and the ocean. In the scalar version of the coupled ocean-atmosphere radiative transfer solver presented by Rozanov et al. [61] we have implemented the simulation of the rotational Raman scattering, vibrational Raman scattering, chlorophyll and colored dissolved organic matter fluorescence. In this paper we discuss and explain the numerical methods used in SCIATRAN to solve the scalar radiative transfer equation including trans-spectral processes, and demonstrate how some selected radiative transfer problems are solved using the SCIATRAN package. In addition we present selected comparisons of SCIATRAN simulations with those published benchmark results, independent radiative transfer models, and various measurements from satellite, ground-based, and ship-borne instruments. The extended SCIATRAN software package along with a detailed User's Guide is made available for scientists and students, who are undertaking their own research typically at universities, via the web page of the Institute of Environmental Physics (IUP), University of Bremen: http://www.iup.physik.uni-bremen.de.

  16. On process optimization considering LCA methodology.

    PubMed

    Pieragostini, Carla; Mussati, Miguel C; Aguirre, Pío

    2012-04-15

    The goal of this work is to research the state-of-the-art in process optimization techniques and tools based on LCA, focused in the process engineering field. A collection of methods, approaches, applications, specific software packages, and insights regarding experiences and progress made in applying the LCA methodology coupled to optimization frameworks is provided, and general trends are identified. The "cradle-to-gate" concept to define the system boundaries is the most used approach in practice, instead of the "cradle-to-grave" approach. Normally, the relationship between inventory data and impact category indicators is linearly expressed by the characterization factors; then, synergic effects of the contaminants are neglected. Among the LCIA methods, the eco-indicator 99, which is based on the endpoint category and the panel method, is the most used in practice. A single environmental impact function, resulting from the aggregation of environmental impacts, is formulated as the environmental objective in most analyzed cases. SimaPro is the most used software for LCA applications in literature analyzed. The multi-objective optimization is the most used approach for dealing with this kind of problems, where the ε-constraint method for generating the Pareto set is the most applied technique. However, a renewed interest in formulating a single economic objective function in optimization frameworks can be observed, favored by the development of life cycle cost software and progress made in assessing costs of environmental externalities. Finally, a trend to deal with multi-period scenarios into integrated LCA-optimization frameworks can be distinguished providing more accurate results upon data availability. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. The Role of Environmental Print in Emergent Literacy

    ERIC Educational Resources Information Center

    Neumann, Michelle M.; Hood, Michelle; Ford, Ruth M.; Neumann, David L.

    2012-01-01

    Young children are surrounded by environmental print on a daily basis. Through their visual exploration of environmental print, coupled with sociocultural experiences, children gain valuable semantic and symbolic knowledge as they make sense of their world. The aim of this review is to examine the question of whether environmental print has value…

  18. Nonlinear dynamics of the CAM circadian rhythm in response to environmental forcing.

    PubMed

    Hartzell, Samantha; Bartlett, Mark S; Virgin, Lawrence; Porporato, Amilcare

    2015-03-07

    Crassulacean acid metabolism (CAM) photosynthesis functions as an endogenous circadian rhythm coupled to external environmental forcings of energy and water availability. This paper explores the nonlinear dynamics of a new CAM photosynthesis model (Bartlett et al., 2014) and investigates the responses of CAM plant carbon assimilation to different combinations of environmental conditions. The CAM model (Bartlett et al., 2014) consists of a Calvin cycle typical of C3 plants coupled to an oscillator of the type employed in the Van der Pol and FitzHugh-Nagumo systems. This coupled system is a function of environmental variables including leaf temperature, leaf moisture potential, and irradiance. Here, we explore the qualitative response of the system and the expected carbon assimilation under constant and periodically forced environmental conditions. The model results show how the diurnal evolution of these variables entrains the CAM cycle with prevailing environmental conditions. While constant environmental conditions generate either steady-state or periodically oscillating responses in malic acid uptake and release, forcing the CAM system with periodic daily fluctuations in light exposure and leaf temperature results in quasi-periodicity and possible chaos for certain ranges of these variables. This analysis is a first step in quantifying changes in CAM plant productivity with variables such as the mean temperature, daily temperature range, irradiance, and leaf moisture potential. Results may also be used to inform model parametrization based on the observed fluctuating regime. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Dynamics of land use and common-resource pressures in terrestrial-aquatic environments

    NASA Astrophysics Data System (ADS)

    Lazarus, E.; Bell, K. P.

    2010-12-01

    Common-pool resource problems can arise in aquatic systems such as lakes, rivers, and open coastlines where individual land-use decisions produce collective, emergent effects at the watershed scale. A body of highly generalized modeling experiments has illustrated ways in which simple, opposing tendencies among individuals—imitative versus self-initiated actions, for example—can result in richly complex behaviors. If the dynamics of those opposing tendencies are translated into different land uses (development, extraction, working land, conservation), each entailing a different environmental consequence, then feedbacks between land-use decisions and resulting changes to the physical environment (which in turn influence subsequent land-use decisions) cause the environmental and social systems of the watershed to become coupled. We present the early results of an exploratory, spatially-extended model that couples a simplified riparian system to a hypothetical group of landowners, each of whom can choose between property development, placing property under a conservation easement, or taking no action and effectively maintaining the property's status quo. As in the generalized experiments, landowner behavior depends on two sets of opposing tendencies, one of which is imitation versus self-initiation. The other is a preference for property consolidation or subdivision; large property holdings can be subdivided into smaller parcels, and small parcels can be bought up by an owner to amass a larger property. Land-use decisions taken by landowners in the model affect the riparian system in process-based ways (sedimentation, eutrophication, water quality) that then inform subsequent social interactions and decisions. Isolating the basic dynamics of this kind of socio-environmental system allows us to pursue a number of questions relevant to resource management. What social and environmental circumstances in this framework result in continuous conservation corridors as opposed to patchworks of easements? How do different kinds of easements, such as those that permit private development and subdivision, affect the integrity of the commons? More broadly, how do changing, heterogeneous patterns of mixed land uses (with different inherent time scales) affect environmental resilience? Dynamical insights from the idealized model dovetail with empirical economic analyses of aquatic-system conservation currently underway in the State of Maine, where opportunities for case studies of specific coupled human/aquatic systems and cross-case comparisons are abundant. This investigation is part of an interdisciplinary project under the auspices of the Sustainability Solutions Initiative at the University of Maine.

  20. Managing Risks

    ERIC Educational Resources Information Center

    Osborn, John E.

    2006-01-01

    Colleges and universities face a wide range of environmental risk. In spite of this, with proper planning, they can avoid emergencies or surprises. Advanced planning, coupled with strategic, technical environmental and legal advice, enable higher-education institutions to keep their environmental budgets under control and predictable. This article…

  1. Magnetic solid-phase extraction based on magnetic multiwalled carbon nanotubes for the simultaneous enantiomeric analysis of five β-blockers in the environmental samples by chiral liquid chromatography coupled with tandem mass spectrometry.

    PubMed

    Wang, Zhaokun; Zhang, Xue; Jiang, Shenmeng; Guo, Xingjie

    2018-04-01

    In this work, the magnetic multiwalled carbon nanotubes (Mag-MWCNTs) were prepared by self-assembly method and characterized by scanning electron microscopy, X-ray powder diffraction, energy dispersive X-ray and vibrating sample magnetometer. Then, these synthetic Mag-MWCNTs were used as sorbents to extract five β-blockers (atenolol, metoprolol, esmolol, pindolol and arotinolol) by magnetic solid-phase extraction. The target analytes adsorbed on Mag-MWCNTs were eluted and determined on a chiral α-acid glycoprotein column coupled with a triple quadrupole mass spectrometry. Eventually, the proposed method was applied to the analysis of the enantiomeric composition of the studied β-blockers in three environmental samples, including river water, influent wastewater and effluent wastewater. Method detection and quantification limits for all enantiomers were in the range of 0.50-1.45 and 1.63-3.75ng/L, respectively. Satisfactory recovery (82.9-95.6%), good intra-day precision (RSD 0.4-10.4%) and inter-day precision (RSD 2.9-7.4%) were also obtained. With numerous advantages such as simplicity of operation, rapidity and high enrichment factor, the newly developed method has potential to assess the enantioselectivity of chiral drugs in ecotoxicity and biodegradation processes, which is also a new expanded application of Mag-MWCNTs in the environmental analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Climatic and evolutionary drivers of phase shifts in the plague epidemics of colonial India.

    PubMed

    Lewnard, Joseph A; Townsend, Jeffrey P

    2016-12-20

    Immune heterogeneity in wild host populations indicates that disease-mediated selection is common in nature. However, the underlying dynamic feedbacks involving the ecology of disease transmission, evolutionary processes, and their interaction with environmental drivers have proven challenging to characterize. Plague presents an optimal system for interrogating such couplings: Yersinia pestis transmission exerts intense selective pressure driving the local persistence of disease resistance among its wildlife hosts in endemic areas. Investigations undertaken in colonial India after the introduction of plague in 1896 suggest that, only a decade after plague arrived, a heritable, plague-resistant phenotype had become prevalent among commensal rats of cities undergoing severe plague epidemics. To understand the possible evolutionary basis of these observations, we developed a mathematical model coupling environmentally forced plague dynamics with evolutionary selection of rats, capitalizing on extensive archival data from Indian Plague Commission investigations. Incorporating increased plague resistance among rats as a consequence of intense natural selection permits the model to reproduce observed changes in seasonal epidemic patterns in several cities and capture experimentally observed associations between climate and flea population dynamics in India. Our model results substantiate Victorian era claims of host evolution based on experimental observations of plague resistance and reveal the buffering effect of such evolution against environmental drivers of transmission. Our analysis shows that historical datasets can yield powerful insights into the transmission dynamics of reemerging disease agents with which we have limited contemporary experience to guide quantitative modeling and inference.

  3. Climatic and evolutionary drivers of phase shifts in the plague epidemics of colonial India

    PubMed Central

    Lewnard, Joseph A.

    2016-01-01

    Immune heterogeneity in wild host populations indicates that disease-mediated selection is common in nature. However, the underlying dynamic feedbacks involving the ecology of disease transmission, evolutionary processes, and their interaction with environmental drivers have proven challenging to characterize. Plague presents an optimal system for interrogating such couplings: Yersinia pestis transmission exerts intense selective pressure driving the local persistence of disease resistance among its wildlife hosts in endemic areas. Investigations undertaken in colonial India after the introduction of plague in 1896 suggest that, only a decade after plague arrived, a heritable, plague-resistant phenotype had become prevalent among commensal rats of cities undergoing severe plague epidemics. To understand the possible evolutionary basis of these observations, we developed a mathematical model coupling environmentally forced plague dynamics with evolutionary selection of rats, capitalizing on extensive archival data from Indian Plague Commission investigations. Incorporating increased plague resistance among rats as a consequence of intense natural selection permits the model to reproduce observed changes in seasonal epidemic patterns in several cities and capture experimentally observed associations between climate and flea population dynamics in India. Our model results substantiate Victorian era claims of host evolution based on experimental observations of plague resistance and reveal the buffering effect of such evolution against environmental drivers of transmission. Our analysis shows that historical datasets can yield powerful insights into the transmission dynamics of reemerging disease agents with which we have limited contemporary experience to guide quantitative modeling and inference. PMID:27791071

  4. A Bioinspired Catalytic Aerobic Oxidative C–H Functionalization of Primary Aliphatic Amines: Synthesis of 1,2-Disubstituted Benzimidazoles

    PubMed Central

    Nguyen, Khac Minh Huy; Largeron, Martine

    2015-01-01

    Aerobic oxidative C–H functionalization of primary aliphatic amines has been accomplished with a biomimetic cooperative catalytic system to furnish 1,2-disubstituted benzimidazoles that play an important role as drug discovery targets. This one-pot atom-economical multistep process, which proceeds under mild conditions, with ambient air and equimolar amounts of each coupling partner, constitutes a convenient environmentally friendly strategy to functionalize non-activated aliphatic amines that remain challenging substrates for non-enzymatic catalytic aerobic systems. PMID:26206475

  5. Effects of pore-scale physics on uranium geochemistry in Hanford sediments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, Qinhong; Ewing, Robert P.

    Overall, this work examines a key scientific issue, mass transfer limitations at the pore-scale, using both new instruments with high spatial resolution, and new conceptual and modeling paradigms. The complementary laboratory and numerical approaches connect pore-scale physics to macroscopic measurements, providing a previously elusive scale integration. This Exploratory research project produced five peer-reviewed journal publications and eleven scientific presentations. This work provides new scientific understanding, allowing the DOE to better incorporate coupled physical and chemical processes into decision making for environmental remediation and long-term stewardship.

  6. Position estimation of transceivers in communication networks

    DOEpatents

    Kent, Claudia A [Pleasanton, CA; Dowla, Farid [Castro Valley, CA

    2008-06-03

    This invention provides a system and method using wireless communication interfaces coupled with statistical processing of time-of-flight data to locate by position estimation unknown wireless receivers. Such an invention can be applied in sensor network applications, such as environmental monitoring of water in the soil or chemicals in the air where the position of the network nodes is deemed critical. Moreover, the present invention can be arranged to operate in areas where a Global Positioning System (GPS) is not available, such as inside buildings, caves, and tunnels.

  7. Constitutional dynamic self-sensing in a zinc(II)/polyiminofluorenes system.

    PubMed

    Giuseppone, Nicolas; Lehn, Jean-Marie

    2004-09-22

    The interaction of an external effector, ZnII ions, with a constitutional dynamic library of fluorescent polyiminofluorenes leads to component exchange, which generates an entity responding by a change in emission to the effector that has induced its formation. The overall coupled system displays a tuning of optical signal, resulting from two synergistic processes: adaptative constitutional reorganization and self-sensing. In broader terms, this work highlights the perspectives opened by constitutional dynamic chemistry toward the design of smart materials, capable of expressing different latent properties in response to environmental conditions.

  8. 40 CFR 201.26 - Procedures for the measurement on receiving property of retarder and car coupling noise.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... receiving property of retarder and car coupling noise. 201.26 Section 201.26 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS NOISE EMISSION STANDARDS FOR TRANSPORTATION... receiving property of retarder and car coupling noise. (a) Retarders—(1) Microphone. The microphone must be...

  9. Nickel-Catalyzed Suzuki-Miyaura Cross-Coupling in a Green Alcohol Solvent for an Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Hie, Liana; Chang, Jonah J.; Garg, Neil K.

    2015-01-01

    A modern undergraduate organic chemistry laboratory experiment involving the Suzuki-Miyaura coupling is reported. Although Suzuki-Miyaura couplings typically employ palladium catalysts in environmentally harmful solvents, this experiment features the use of inexpensive nickel catalysis, in addition to a "green" alcohol solvent. The…

  10. Environmental fatigue of an Al-Li-Cu alloy. Part 3: Modeling of crack tip hydrogen damage

    NASA Technical Reports Server (NTRS)

    Piascik, Robert S.; Gangloff, Richard P.

    1992-01-01

    Environmental fatigue crack propagation rates and microscopic damage modes in Al-Li-Cu alloy 2090 (Parts 1 and 2) are described by a crack tip process zone model based on hydrogen embrittlement. Da/dN sub ENV equates to discontinuous crack advance over a distance, delta a, determined by dislocation transport of dissolved hydrogen at plastic strains above a critical value; and to the number of load cycles, delta N, required to hydrogenate process zone trap sites that fracture according to a local hydrogen concentration-tensile stress criterion. Transgranular (100) cracking occurs for process zones smaller than the subgrain size, and due to lattice decohesion or hydride formation. Intersubgranular cracking dominates when the process zone encompasses one or more subgrains so that dislocation transport provides hydrogen to strong boundary trapping sites. Multi-sloped log da/dN-log delta K behavior is produced by process zone plastic strain-hydrogen-microstructure interactions, and is determined by the DK dependent rates and proportions of each parallel cracking mode. Absolute values of the exponents and the preexponential coefficients are not predictable; however, fractographic measurements theta sub i coupled with fatigue crack propagation data for alloy 2090 established that the process zone model correctly describes fatigue crack propagation kinetics. Crack surface films hinder hydrogen uptake and reduce da/dN and alter the proportions of each fatigue crack propagation mode.

  11. Meta-studies in land use science: Current coverage and prospects.

    PubMed

    van Vliet, Jasper; Magliocca, Nicholas R; Büchner, Bianka; Cook, Elizabeth; Rey Benayas, José M; Ellis, Erle C; Heinimann, Andreas; Keys, Eric; Lee, Tien Ming; Liu, Jianguo; Mertz, Ole; Meyfroidt, Patrick; Moritz, Mark; Poeplau, Christopher; Robinson, Brian E; Seppelt, Ralf; Seto, Karen C; Verburg, Peter H

    2016-02-01

    Land use science has traditionally used case-study approaches for in-depth investigation of land use change processes and impacts. Meta-studies synthesize findings across case-study evidence to identify general patterns. In this paper, we provide a review of meta-studies in land use science. Various meta-studies have been conducted, which synthesize deforestation and agricultural land use change processes, while other important changes, such as urbanization, wetland conversion, and grassland dynamics have hardly been addressed. Meta-studies of land use change impacts focus mostly on biodiversity and biogeochemical cycles, while meta-studies of socioeconomic consequences are rare. Land use change processes and land use change impacts are generally addressed in isolation, while only few studies considered trajectories of drivers through changes to their impacts and their potential feedbacks. We provide a conceptual framework for linking meta-studies of land use change processes and impacts for the analysis of coupled human-environmental systems. Moreover, we provide suggestions for combining meta-studies of different land use change processes to develop a more integrated theory of land use change, and for combining meta-studies of land use change impacts to identify tradeoffs between different impacts. Land use science can benefit from an improved conceptualization of land use change processes and their impacts, and from new methods that combine meta-study findings to advance our understanding of human-environmental systems.

  12. Socio-hydrologic modeling to understand and mediate the competition for water between agriculture development and environmental health: Murrumbidgee River basin, Australia

    NASA Astrophysics Data System (ADS)

    van Emmerik, T. H. M.; Li, Z.; Sivapalan, M.; Pande, S.; Kandasamy, J.; Savenije, H. H. G.; Chanan, A.; Vigneswaran, S.

    2014-10-01

    Competition for water between humans and ecosystems is set to become a flash point in the coming decades in many parts of the world. An entirely new and comprehensive quantitative framework is needed to establish a holistic understanding of that competition, thereby enabling the development of effective mediation strategies. This paper presents a modeling study centered on the Murrumbidgee River basin (MRB). The MRB has witnessed a unique system dynamics over the last 100 years as a result of interactions between patterns of water management and climate driven hydrological variability. Data analysis has revealed a pendulum swing between agricultural development and restoration of environmental health and ecosystem services over different stages of basin-scale water resource development. A parsimonious, stylized, quasi-distributed coupled socio-hydrologic system model that simulates the two-way coupling between human and hydrological systems of the MRB is used to mimic and explain dominant features of the pendulum swing. The model consists of coupled nonlinear ordinary differential equations that describe the interaction between five state variables that govern the co-evolution: reservoir storage, irrigated area, human population, ecosystem health, and environmental awareness. The model simulations track the propagation of the external climatic and socio-economic drivers through this coupled, complex system to the emergence of the pendulum swing. The model results point to a competition between human "productive" and environmental "restorative" forces that underpin the pendulum swing. Both the forces are endogenous, i.e., generated by the system dynamics in response to external drivers and mediated by humans through technology change and environmental awareness, respectively. Sensitivity analysis carried out with the model further reveals that socio-hydrologic modeling can be used as a tool to explain or gain insight into observed co-evolutionary dynamics of diverse human-water coupled systems. This paper therefore contributes to the ultimate development of a generic modeling framework that can be applied to human-water coupled systems in different climatic and socio-economic settings.

  13. Challenges to achievement of metal sustainability in our high-tech society

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Izatt, Reed M.; Izatt, Steven R.; Bruening, Ronald L.

    Achievement of sustainability in metal life cycles from mining of virgin ore to consumer and industrial devices to end-of-life products requires greatly increased recycling and improved processing of metals. Electronic and other high-tech products containing precious, toxic, and specialty metals usually have short lifetimes and low recycling rates. Products containing these metals generally are incinerated, discarded as waste in landfills, or dismantled in informal recycling using crude and environmentally irresponsible procedures. Low metal recycling rates coupled with increasing demand for products containing them necessitate increased mining with attendant environmental, health, energy, water, and carbon-footprint consequences. In this tutorial review, challengesmore » to achieving metal sustainability in present high-tech society are presented; health, environmental, and economic incentives for various stakeholders to improve metal sustainability are discussed; a case for technical improvements in separations technology, especially employing molecular recognition, is given; and global consequences of continuing on the present path are examined.« less

  14. Geography for a Changing World - A science strategy for the geographic research of the U.S. Geological Survey, 2005-2015

    USGS Publications Warehouse

    McMahon, Gerard; Benjamin, Susan P.; Clarke, Keith; Findley, John E.; Fisher, Robert N.; Graf, William L.; Gundersen, Linda C.; Jones, John W.; Loveland, Thomas R.; Roth, Keven S.; Usery, E. Lynn; Wood, Nathan J.

    2005-01-01

    This report presents a science strategy for the geographic research of the U.S. Geological Survey (USGS) for the years 2005-2015. The common thread running through the vision, mission, and science goals presented in the plan is that USGS geographers will provide national leadership to understand coupled human-environmental systems in the face of land change and will deliver pertinent information to decisionmakers on the vulnerability and resilience of these systems. We define land change science as the study of the human and environment dynamics that give rise to changed land use, cover, and surface form.A number of realities shape the strategic context of this plan:The Department of Interior Strategic Plan focuses on meeting society’s resource needs and sustaining the Nation’s life support systems, underscoring the importance of characterizing and understanding coupled human-environmental systems.In redefining its mission in the mid-1990s, the USGS envisions itself as an integrated natural science and information agency. The USGS will assume a national leadership role in the use of science to develop knowledge about the web of relations that couple biophysical and human systems and translate this knowledge into unbiased, reliable information that meets important societal information needs.The following trends will influence USGS geography-oriented science activities over the next decade. Most of the emerging earth science issues that the USGS will address are geographic phenomena. A growing international concern for aligning society’s development activities with environmental limits has led to an articulation of a science agenda associated with global environmental change, vulnerability, and resilience. Earth science investigations have evolved toward the study of very large areas, and the resulting huge volumes of data are challenging to manage and understand. Finally, scientists and the public face the challenge of gaining intelligent insights about geographic and environmental processes from these data, with the ultimate goal of guiding resource-management decisions.The first four science goals in the plan support understanding the human and environmental dynamics of land change. Each science goal has an associated set of strategic actions to achieve the goal. These goals and actions are consistent with national science priorities and the Department of Interior and USGS missions, take advantage of existing expertise, and lead to the strengthening of critical geographic research capacities that do not exist in other USGS disciplines.

  15. Hydrogen-driven asymmetric reduction of hydroxyacetone to (R)-1,2-propanediol by Ralstonia eutropha transformant expressing alcohol dehydrogenase from Kluyveromyces lactis.

    PubMed

    Oda, Takahiro; Oda, Koji; Yamamoto, Hiroaki; Matsuyama, Akinobu; Ishii, Masaharu; Igarashi, Yasuo; Nishihara, Hirofumi

    2013-01-10

    Conversion of industrial processes to more nature-friendly modes is a crucial subject for achieving sustainable development. Utilization of hydrogen-oxidation reactions by hydrogenase as a driving force of bioprocess reaction can be an environmentally ideal method because the reaction creates no pollutants. We expressed NAD-dependent alcohol dehydrogenase from Kluyveromyces lactis in a hydrogen-oxidizing bacterium: Ralstonia eutropha. This is the first report of hydrogen-driven in vivo coupling reaction of the alcohol dehydrogenase and indigenous soluble NAD-reducing hydrogenase. Asymmetric reduction of hydroxyacetone to (R)-1,2-propanediol, which is a commercial building block for antibacterial agents, was performed using the transformant as the microbial cell catalyst. The two enzymes coupled in vitro in vials without a marked decrease of reactivity during the 20 hr reaction because of the hydrogenase reaction, which generates no by-product that affects enzymes. Alcohol dehydrogenase was expressed functionally in R. eutropha in an activity level equivalent to that of indigenous NAD-reducing hydrogenase under the hydrogenase promoter. The hydrogen-driven in vivo coupling reaction proceeded only by the transformant cell without exogenous addition of a cofactor. The decrease of reaction velocity at higher concentration of hydroxyacetone was markedly reduced by application of an in vivo coupling system. Production of (R)-1,2-propanediol (99.8% e.e.) reached 67.7 g/l in 76 hr with almost a constant rate using a jar fermenter. The reaction velocity under 10% PH2 was almost equivalent to that under 100% hydrogen, indicating the availability of crude hydrogen gas from various sources. The in vivo coupling system enabled cell-recycling as catalysts. Asymmetric reduction of hydroxyacetone by a coupling reaction of the two enzymes continued in both in vitro and in vivo systems in the presence of hydrogen. The in vivo reaction system using R. eutropha transformant expressing heterologous alcohol dehydrogenase showed advantages for practical usage relative to the in vitro coupling system. The results suggest a hopeful perspective of the hydrogen-driven bioprocess as an environmentally outstanding method to achieve industrial green innovation. Hydrogen-oxidizing bacteria can be useful hosts for the development of hydrogen-driven microbial cell factories.

  16. Enantiomeric Profiling of Chiral Pharmacologically Active Compounds in the Environment with the Usage of Chiral Liquid Chromatography 
Coupled with Tandem Mass Spectrometry

    PubMed Central

    Camacho-Muñoz, Dolores; Petrie, Bruce; Castrignanò, Erika; Kasprzyk-Hordern, Barbara

    2016-01-01

    The issue of drug chirality is attracting increasing attention among the scientific community. The phenomenon of chirality has been overlooked in environmental research (environmental occurrence, fate and toxicity) despite the great impact that chiral pharmacologically active compounds (cPACs) can provoke on ecosystems. The aim of this paper is to introduce the topic of chirality and its implications in environmental contamination. Special attention has been paid to the most recent advances in chiral analysis based on liquid chromatography coupled with mass spectrometry and the most popular protein based chiral stationary phases. Several groups of cPACs of environmental relevance, such as illicit drugs, human and veterinary medicines were discussed. The increase in the number of papers published in the area of chiral environmental analysis indicates that researchers are actively pursuing new opportunities to provide better understanding of environmental impacts resulting from the enantiomerism of cPACs. PMID:27713682

  17. Development and coupling analysis of active skin antenna

    NASA Astrophysics Data System (ADS)

    Zhou, Jinzhu; Huang, Jin; He, Qingqang; Tang, Baofu; Song, Liwei

    2017-02-01

    An active skin antenna is a multifunctional composite structure that can provide load-bearing structure and steerable beam pointing functions, and is usually installed in the structural surface of aircraft, warships, and armored vehicles. This paper presents an innovative design of the active skin antenna, which consists of a package layer, control and signal processing layer, and RF (radio frequency) layer. The RF layer is fabricated by low temperature co-fired ceramics, with 64 microstrip antenna elements, tile transmitting and receiving modules, microchannel heat sinks, and feeding networks integrated into a functional block 2.8 mm thick. In this paper, a full-sized prototype of an active skin antenna was designed, fabricated, and tested. Moreover, a coupling analysis method was presented to evaluate the mechanical and electromagnetic performance of the active skin antenna subjected to aerodynamic loads. A deformed experimental system was built to validate the effectiveness of the coupling analysis method, which was also implemented to evaluate the performance of the active skin antenna when subjected to aerodynamic pressure. The fabricated specimen demonstrated structural configuration feasibility, and superior environmental load resistance.

  18. Spatio-Temporal Process Variability in Watershed Scale Wetland Restoration Planning

    NASA Astrophysics Data System (ADS)

    Evenson, G. R.

    2012-12-01

    Watershed scale restoration decision making processes are increasingly informed by quantitative methodologies providing site-specific restoration recommendations - sometimes referred to as "systematic planning." The more advanced of these methodologies are characterized by a coupling of search algorithms and ecological models to discover restoration plans that optimize environmental outcomes. Yet while these methods have exhibited clear utility as decision support toolsets, they may be critiqued for flawed evaluations of spatio-temporally variable processes fundamental to watershed scale restoration. Hydrologic and non-hydrologic mediated process connectivity along with post-restoration habitat dynamics, for example, are commonly ignored yet known to appreciably affect restoration outcomes. This talk will present a methodology to evaluate such spatio-temporally complex processes in the production of watershed scale wetland restoration plans. Using the Tuscarawas Watershed in Eastern Ohio as a case study, a genetic algorithm will be coupled with the Soil and Water Assessment Tool (SWAT) to reveal optimal wetland restoration plans as measured by their capacity to maximize nutrient reductions. Then, a so-called "graphical" representation of the optimization problem will be implemented in-parallel to promote hydrologic and non-hydrologic mediated connectivity amongst existing wetlands and sites selected for restoration. Further, various search algorithm mechanisms will be discussed as a means of accounting for temporal complexities such as post-restoration habitat dynamics. Finally, generalized patterns of restoration plan optimality will be discussed as an alternative and possibly superior decision support toolset given the complexity and stochastic nature of spatio-temporal process variability.

  19. The GIIDA (Management of the CNR Environmental Data for Interoperability) project

    NASA Astrophysics Data System (ADS)

    Nativi, S.

    2009-04-01

    This work presents the GIIDA (Gestione Integrata e Interoperativa dei Dati Ambientali del CNR) inter-departimental project of the Italian National Research Council (CNR). The project is an initiative of the Earth and Environment Department (Dipartimento Terra e Ambiente) of the CNR. GIIDA mission is "To implement the Spatial Information Infrastructure (SII) of CNR for Environmental and Earth Observation data". The project aims to design and develop a multidisciplinary cyber-infrastructure for the management, processing and evaluation of Earth and environmental data. This infrastructure will contribute to the Italian presence in international projects and initiatives, such as: INSPIRE, GMES, GEOSS and SEIS. The main GIIDA goals are: • Networking: To create a network of CNR Institutes for implementing a common information space and sharing spatial resources. • Observation: Re-engineering the environmental observation system of CNR • Modeling: Re-engineering the environmental modeling system del CNR • Processing: Re-engineering the environmental processing system del CNR • Mediation: To define mediation methods and instruments for implementing the international interoperability standards. The project started in July 2008 releasing a specification document of the GIIDA architecture for interoperability and security. Based on these documents, a Call for Proposals was issued in September 2008. GIIDA received 23 proposed pilots from 16 different Institutes belonging to five CNR Departments and from 15 non-CNR Institutions (e.g. three Italian regional administrations, three national research centers, four universities, some SMEs). These pilot were divided into thematic areas. In fact, GIIDA considers seven main thematic areas/domains: • Biodiversity; • Climate Changes; • Air Quality; • Soil and Water Quality; • Risks; • Infrastructures for Research and Public Administrations; • Sea and Marine resources Each of these thematic areas is covered by a Working Group which coordinates the activities and the achievements of the respective pilots. Working Groups are called to develop for each area: 1) a specific Web Portal; 2) a thematic catalog service; 3) a thematic thesaurus service; 4) a thematic Wiki; 5) standard access and view services for thematic resources -such as: datasets, models, and processing services; 6) a couple of significant use scenarios to be demonstrated.

  20. The effect of freezing on reactions with environmental impact.

    PubMed

    O'Concubhair, Ruairí; Sodeau, John R

    2013-11-19

    The knowledge that the freezing process can accelerate certain chemical reactions has been available since the 1960s, particularly in relation to the food industry. However, investigations into such effects on environmentally relevant reactions have only been carried out since the late 1980s. Some 20 years later, the field has matured and scientists have conducted research into various important processes such as the oxidation of nitrite ions to nitrates, sulfites to sulfates, and elemental mercury to inorganic mercury. Field observations mainly carried out in the polar regions have driven this work. For example, researchers have found that both ozone and mercury are removed from the troposphere completely (and almost instantaneously) at the time of Arctic polar sunrise. The monitoring activities suggested that both the phenomena were caused by involvement of bromine (and possibly iodine) chemistry. Scientists investigating the production of interhalide products (bromine and iodine producing interhalides) in frozen aqueous solutions have found that these reactions result in both rate accelerations and unexpected products. Furthermore, these scientists did this research with environmentally relevant concentrations of reagents, thereby suggesting that these reactions could occur in the polar regions. The conversion of elemental mercury to more oxidized forms has also shown that the acceleration of reactions can occur when environmentally relevant concentrations of Hg(0) and oxidants are frozen together in aqueous solutions. These observations, coupled with previous investigations into the effect of freezing on environmental reactions, lead us to conclude that this type of chemistry could potentially play a significant role in the chemical processing of a wide variety of inorganic components in polar regions. More recently, researchers have recognized the implications of these complementary field and laboratory findings toward human health and climate change. In this Account, we focus on the chemical and physical mechanisms that may promote novel chemistry and rate accelerations when water-ice is present. Future prospects will likely concentrate, once again, on the low-temperature chemistry of organic compounds, such as the humic acids, which are known cryospheric contaminants. Furthermore, data on the kinetics and thermodynamics of all types of reaction promoted by the freezing process would provide much assistance in determining their implications to environmental computer models.

  1. Predicting Formation Damage in Aquifer Thermal Energy Storage Systems Utilizing a Coupled Hydraulic-Thermal-Chemical Reservoir Model

    NASA Astrophysics Data System (ADS)

    Müller, Daniel; Regenspurg, Simona; Milsch, Harald; Blöcher, Guido; Kranz, Stefan; Saadat, Ali

    2014-05-01

    In aquifer thermal energy storage (ATES) systems, large amounts of energy can be stored by injecting hot water into deep or intermediate aquifers. In a seasonal production-injection cycle, water is circulated through a system comprising the porous aquifer, a production well, a heat exchanger and an injection well. This process involves large temperature and pressure differences, which shift chemical equilibria and introduce or amplify mechanical processes. Rock-fluid interaction such as dissolution and precipitation or migration and deposition of fine particles will affect the hydraulic properties of the porous medium and may lead to irreversible formation damage. In consequence, these processes determine the long-term performance of the ATES system and need to be predicted to ensure the reliability of the system. However, high temperature and pressure gradients and dynamic feedback cycles pose challenges on predicting the influence of the relevant processes. Within this study, a reservoir model comprising a coupled hydraulic-thermal-chemical simulation was developed based on an ATES demonstration project located in the city of Berlin, Germany. The structural model was created with Petrel, based on data available from seismic cross-sections and wellbores. The reservoir simulation was realized by combining the capabilities of multiple simulation tools. For the reactive transport model, COMSOL Multiphysics (hydraulic-thermal) and PHREEQC (chemical) were combined using the novel interface COMSOL_PHREEQC, developed by Wissmeier & Barry (2011). It provides a MATLAB-based coupling interface between both programs. Compared to using COMSOL's built-in reactive transport simulator, PHREEQC additionally calculates adsorption and reaction kinetics and allows the selection of different activity coefficient models in the database. The presented simulation tool will be able to predict the most important aspects of hydraulic, thermal and chemical transport processes relevant to formation damage in ATES systems. We would like to present preliminary results of the structural reservoir model and the hydraulic-thermal-chemical coupling for the demonstration site. Literature: Wissmeier, L. and Barry, D.A., 2011. Simulation tool for variably saturated flow with comprehensive geochemical reactions in two- and three-dimensional domains. Environmental Modelling & Software 26, 210-218.

  2. State of the art of produced water treatment.

    PubMed

    Jiménez, S; Micó, M M; Arnaldos, M; Medina, F; Contreras, S

    2018-02-01

    Produced water (PW) is the wastewater generated when water from underground reservoirs is brought to the surface during oil or gas extraction. PW is generated in large amounts and has a complex composition, containing various toxic organic and inorganic compounds. PW is currently treated in conventional trains that include phase separators, decanters, cyclones and coarse filters in order to comply with existing regulation for discharge. These treatment trains do not achieve more restrictive limitations related to the reuse of the effluent (reinjection into extraction wells) or other beneficial uses (e.g., irrigation). Therefore, and to prevent environmental pollution, further polishing processes need to be carried out. Characterization of the PW to determine major constituents is the first step to select the optimum treatment for PW, coupled with environmental factors, economic considerations, and local regulatory framework. This review tries to provide an overview of different treatments that are being applied to polish this type of effluents. These technologies include membranes, physical, biological, thermal or chemical treatments, where special emphasis has been made on advanced oxidation processes due to the advantages offered by these processes. Commercial treatments, based on the combination, modification and improvement of simpler treatments, were also discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. BioEarth: Envisioning and developing a new regional earth system model to inform natural and agricultural resource management

    DOE PAGES

    Adam, Jennifer C.; Stephens, Jennie C.; Chung, Serena H.; ...

    2014-04-24

    Uncertainties in global change impacts, the complexities associated with the interconnected cycling of nitrogen, carbon, and water present daunting management challenges. Existing models provide detailed information on specific sub-systems (e.g., land, air, water, and economics). An increasing awareness of the unintended consequences of management decisions resulting from interconnectedness of these sub-systems, however, necessitates coupled regional earth system models (EaSMs). Decision makers’ needs and priorities can be integrated into the model design and development processes to enhance decision-making relevance and “usability” of EaSMs. BioEarth is a research initiative currently under development with a focus on the U.S. Pacific Northwest region thatmore » explores the coupling of multiple stand-alone EaSMs to generate usable information for resource decision-making. Direct engagement between model developers and non-academic stakeholders involved in resource and environmental management decisions throughout the model development process is a critical component of this effort. BioEarth utilizes a bottom-up approach for its land surface model that preserves fine spatial-scale sensitivities and lateral hydrologic connectivity, which makes it unique among many regional EaSMs. Here, we describe the BioEarth initiative and highlights opportunities and challenges associated with coupling multiple stand-alone models to generate usable information for agricultural and natural resource decision-making.« less

  4. Environmental niche divergence among three dune shrub sister species with parapatric distributions

    PubMed Central

    Chefaoui, Rosa M.; Correia, Otília; Bonal, Raúl; Hortal, Joaquín

    2017-01-01

    Abstract Background and Aims The geographical distributions of species are constrained by their ecological requirements. The aim of this work was to analyse the effects of environmental conditions, historical events and biogeographical constraints on the diversification of the three species of the western Mediterranean shrub genus Stauracanthus, which have a parapatric distribution in the Iberian Peninsula. Methods Ecological niche factor analysis and generalized linear models were used to measure the response of all Stauracanthus species to the environmental gradients and map their potential distributions in the Iberian Peninsula. The bioclimatic niche overlap between the three species was determined by using Schoener's index. The genetic differentiation of the Iberian and northern African populations of Stauracanthus species was characterized with GenalEx. The effects on genetic distances of the most important environmental drivers were assessed through Mantel tests and non-metric multidimensional scaling. Key Results The three Stauracanthus species show remarkably similar responses to climatic conditions. This supports the idea that all members of this recently diversified clade retain common adaptations to climate and consequently high levels of climatic niche overlap. This contrasts with the diverse edaphic requirements of Stauracanthus species. The populations of the S. genistoides–spectabilis clade grow on Miocene and Pliocene fine-textured sedimentary soils, whereas S. boivinii, the more genetically distant species, occurs on older and more coarse-textured sedimentary substrates. These patterns of diversification are largely consistent with a stochastic process of geographical range expansion and fragmentation coupled with niche evolution in the context of spatially complex environmental fluctuations. Conclusions: The combined analysis of the distribution, realized environmental niche and phylogeographical relationships of parapatric species proposed in this work allows integration of the biogeographical, ecological and evolutionary processes driving the evolution of species adaptations and how they determine their current geographical ranges. PMID:28334085

  5. LSBB: a Low Noise Laboratory for Inter--Disciplinary Underground Science and Technology in Rustrel--Pays d'Apt, Vaucluse, France

    NASA Astrophysics Data System (ADS)

    Gaffet, S.

    2008-12-01

    Located in the Provence-Alpes--Côte d'Azur region (Southern France), LSBB is an underground facility that is dedicated since 10 years ago, to interdisciplinary fundamental and applied R&D activities in a low level anthropogenic area that secures the site with one of the lowest environmental noise in the world. LSBB is both a host-laboratory for private and academic experiments and a unique access-laboratory to study near- surface multi-physics environmental processes. This site offers operational facilities characterized by a fully connected fiber-optics network managed by a team of 3 permanent engineers and the collaboration with more than 30 research units in Europe. Initially designed for the French nuclear defence and converted in 1997 into an academic laboratory, LSBB is a hardened facility made of 3.7~km of horizontal galleries and vaults buried 500~m deep within the unsaturated zone of a carbonate platform which is a typical analogue of the currently exploited water and oil reservoirs of the Middle--East. Another major attraction of the LSBB is that it hosts a unique--in--the--world broad low-pass filter magnetic shielded zone (1500~m3 with electromagnetic noise level below 2~fT/√Hz for frequencies above 50~Hz). Thanks to such an exceptional environmental and technological context, LSBB provides one of the best european opportunities for the development of research projects related to near-surface imaging and multiscale and multiphysics coupled processes in natural porous media; magnetic field perturbations coupled to seismic wave excitations; thermo--hydromechanical and chemical fluid--rock interaction in heterogeneous carbonates; dark matter research; reliability and sensitivity to the natural radioactive environment of nano-- electronic and nano--structures. Projects interact through co--sharing of the multi--parametric and at--the-- leading--edge measurements and results, that are centralised in a dedicated internet plateform.

  6. Large-scale modeling on the fate and transport of polycyclic aromatic hydrocarbons (PAHs) in multimedia over China

    NASA Astrophysics Data System (ADS)

    Huang, Y.; Liu, M.; Wada, Y.; He, X.; Sun, X.

    2017-12-01

    In recent decades, with rapid economic growth, industrial development and urbanization, expanding pollution of polycyclic aromatic hydrocarbons (PAHs) has become a diversified and complicated phenomenon in China. However, the availability of sufficient monitoring activities for PAHs in multi-compartment and the corresponding multi-interface migration processes are still limited, especially at a large geographic area. In this study, we couple the Multimedia Fate Model (MFM) to the Community Multi-Scale Air Quality (CMAQ) model in order to consider the fugacity and the transient contamination processes. This coupled dynamic contaminant model can evaluate the detailed local variations and mass fluxes of PAHs in different environmental media (e.g., air, surface film, soil, sediment, water and vegetation) across different spatial (a county to country) and temporal (days to years) scales. This model has been applied to a large geographical domain of China at a 36 km by 36 km grid resolution. The model considers response characteristics of typical environmental medium to complex underlying surface. Results suggest that direct emission is the main input pathway of PAHs entering the atmosphere, while advection is the main outward flow of pollutants from the environment. In addition, both soil and sediment act as the main sink of PAHs and have the longest retention time. Importantly, the highest PAHs loadings are found in urbanized and densely populated regions of China, such as Yangtze River Delta and Pearl River Delta. This model can provide a good scientific basis towards a better understanding of the large-scale dynamics of environmental pollutants for land conservation and sustainable development. In a next step, the dynamic contaminant model will be integrated with the continental-scale hydrological and water resources model (i.e., Community Water Model, CWatM) to quantify a more accurate representation and feedbacks between the hydrological cycle and water quality at even larger geographical domains. Keywords: PAHs; Community multi-scale air quality model; Multimedia fate model; Land use

  7. Multimedia Modeling System Response to Regional Land Management Change

    NASA Astrophysics Data System (ADS)

    Cooter, E. J.

    2015-12-01

    A multi-media system of nitrogen and co-pollutant models describing critical physical and chemical processes that cascade synergistically and competitively through the environment, the economy and society has been developed at the USEPA Office of Research and Development. It is populated with linked or fully coupled models that address nutrient research questions such as, "How might future policy, climate or land cover change in the Mississippi River Basin affect Nitrogen and Phosphorous loadings to the Gulf of Mexico" or, "What are the management implications of regional-scale land management changes for the sustainability of air, land and water quality?" This second question requires explicit consideration of economic (e.g. sector prices) and societal (e.g. land management) factors. Metrics that illustrate biosphere-atmosphere interactions such as atmospheric PM2.5 concentrations, atmospheric N loading to surface water, soil organic N and N percolation to groundwater are calculated. An example application has been completed that is driven by a coupled agricultural and energy sector model scenario. The economic scenario assumes that by 2022 there is: 1) no detectable change in weather patterns relative to 2002; 2) a concentration of stover processing facilities in the Upper Midwest; 3) increasing offshore Pacific and Atlantic marine transportation; and 4) increasing corn, soybean and wheat production that meets future demand for food, feed and energy feedstocks. This production goal is reached without adding or removing agricultural land area whose extent is defined by the National Land Cover Dataset (NLCD) 2002v2011 classes 81 and 82. This goal does require, however, crop shifts and agricultural management changes. The multi-media system response over our U.S. 12km rectangular grid resolution analysis suggests that there are regions of potential environmental and health costs, as well as large areas that could experience unanticipated environmental and health benefits. Alternative land management that may reduce multimedia environmental costs and enhance benefits will be discussed.

  8. iTREE: Long-term variability of tree growth in a changing environment - identifying physiological mechanisms using stable C and O isotopes in tree rings.

    NASA Astrophysics Data System (ADS)

    Siegwolf, R. T. W.; Buchmann, N.; Frank, D.; Joos, F.; Kahmen, A.; Treydte, K.; Leuenberger, M.; Saurer, M.

    2012-04-01

    Trees play are a critical role in the carbon cycle - their photosynthetic assimilation is one of the largest terrestrial carbon fluxes and their standing biomass represents the largest carbon pool of the terrestrial biosphere. Understanding how tree physiology and growth respond to long-term environmental change is pivotal to predict the magnitude and direction of the terrestrial carbon sink. iTREE is an interdisciplinary research framework to capitalize on synergies among leading dendroclimatologists, plant physiologists, isotope specialists, and global carbon cycle modelers with the objectives of reducing uncertainties related to tree/forest growth in the context of changing natural environments. Cross-cutting themes in our project are tree rings, stable isotopes, and mechanistic modelling. We will (i) establish a European network of tree-ring based isotope time-series to retrodict interannual to long-term tree physiological changes, (ii) conduct laboratory and field experiments to adapt a mechanistic isotope model to derive plant physiological variables from tree-ring isotopes, (iii) implement this model into a dynamic global vegetation model, and perform subsequent model-data validation exercises to refine model representation of plant physiological processes and (iv) attribute long-term variation in tree growth to plant physiological and environmental drivers, and identify how our refined knowledge revises predictions of the coupled carbon-cycle climate system. We will contribute to i) advanced quantifications of long-term variation in tree growth across Central Europe, ii) novel long-term information on key physiological processes that underlie variations in tree growth, and iii) improved carbon cycle models that can be employed to revise predictions of the coupled carbon-cycle climate system. Hence iTREE will significantly contribute towards a seamless understanding of the responses of terrestrial ecosystems to long-term environmental change, and ultimately help reduce uncertainties of the magnitude and direction of the past and future terrestrial carbon sink.

  9. The Role of Ultrasound on Advanced Oxidation Processes.

    PubMed

    Babu, Sundaram Ganesh; Ashokkumar, Muthupandian; Neppolian, Bernaurdshaw

    2016-10-01

    This chapter describes the use of ultrasound in remediation of wastewater contaminated with organic pollutants in the absence and presence of other advanced oxidation processes (AOPs) such as sonolysis, sono-ozone process, sonophotocatalysis, sonoFenton systems and sonophoto-Fenton methods in detail. All these methods are explained with the suitable literature illustrations. In most of the cases, hybrid AOPs (combination of ultrasound with one or more AOPs) resulted in superior efficacy to that of individual AOP. The advantageous effects such as additive and synergistic effects obtained by operating the hybrid AOPs are highlighted with appropriate examples. It is worth to mention here that the utilization of ultrasound is not only restricted in preparation of modern active catalysts but also extensively used for the wastewater treatment. Interestingly, ultrasound coupled AOPs are operationally simple, efficient, and environmentally benign, and can be readily applied for large scale industrial processes which make them economically viable.

  10. Clinical processes in behavioral couples therapy.

    PubMed

    Fischer, Daniel J; Fink, Brandi C

    2014-03-01

    Behavioral couples therapy is a broad term for couples therapies that use behavioral techniques based on principles of operant conditioning, such as reinforcement. Behavioral shaping and rehearsal and acceptance are clinical processes found across contemporary behavioral couples therapies. These clinical processes are useful for assessment and case formulation, as well as teaching couples new methods of conflict resolution. Although these clinical processes assist therapists in achieving efficient and effective therapeutic change with distressed couples by rapidly stemming couples' corrosive affective exchanges, they also address the thoughts, emotions, and issues of trust and intimacy that are important aspects of the human experience in the context of a couple. Vignettes are provided to illustrate the clinical processes described. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  11. Modeling coupled nanoparticle aggregation and transport in porous media: A Lagrangian approach

    NASA Astrophysics Data System (ADS)

    Taghavy, Amir; Pennell, Kurt D.; Abriola, Linda M.

    2015-01-01

    Changes in nanoparticle size and shape due to particle-particle interactions (i.e., aggregation or agglomeration) may significantly alter particle mobility and retention in porous media. To date, however, few modeling studies have considered the coupling of transport and particle aggregation processes. The majority of particle transport models employ an Eulerian modeling framework and are, consequently, limited in the types of collisions and aggregate sizes that can be considered. In this work, a more general Lagrangian modeling framework is developed and implemented to explore coupled nanoparticle aggregation and transport processes. The model was verified through comparison of model simulations to published results of an experimental and Eulerian modeling study (Raychoudhury et al., 2012) of carboxymethyl cellulose (CMC)-modified nano-sized zero-valent iron particle (nZVI) transport and retention in water-saturated sand columns. A model sensitivity analysis reveals the influence of influent particle concentration (ca. 70 to 700 mg/L), primary particle size (10-100 nm) and pore water velocity (ca. 1-6 m/day) on particle-particle, and, consequently, particle-collector interactions. Model simulations demonstrate that, when environmental conditions promote particle-particle interactions, neglecting aggregation effects can lead to under- or over-estimation of nanoparticle mobility. Results also suggest that the extent to which higher order particle-particle collisions influence aggregation kinetics will increase with the fraction of primary particles. This work demonstrates the potential importance of time-dependent aggregation processes on nanoparticle mobility and provides a numerical model capable of capturing/describing these interactions in water-saturated porous media.

  12. Modeling coupled nanoparticle aggregation and transport in porous media: a Lagrangian approach.

    PubMed

    Taghavy, Amir; Pennell, Kurt D; Abriola, Linda M

    2015-01-01

    Changes in nanoparticle size and shape due to particle-particle interactions (i.e., aggregation or agglomeration) may significantly alter particle mobility and retention in porous media. To date, however, few modeling studies have considered the coupling of transport and particle aggregation processes. The majority of particle transport models employ an Eulerian modeling framework and are, consequently, limited in the types of collisions and aggregate sizes that can be considered. In this work, a more general Lagrangian modeling framework is developed and implemented to explore coupled nanoparticle aggregation and transport processes. The model was verified through comparison of model simulations to published results of an experimental and Eulerian modeling study (Raychoudhury et al., 2012) of carboxymethyl cellulose (CMC)-modified nano-sized zero-valent iron particle (nZVI) transport and retention in water-saturated sand columns. A model sensitivity analysis reveals the influence of influent particle concentration (ca. 70 to 700 mg/L), primary particle size (10-100 nm) and pore water velocity (ca. 1-6 m/day) on particle-particle, and, consequently, particle-collector interactions. Model simulations demonstrate that, when environmental conditions promote particle-particle interactions, neglecting aggregation effects can lead to under- or over-estimation of nanoparticle mobility. Results also suggest that the extent to which higher order particle-particle collisions influence aggregation kinetics will increase with the fraction of primary particles. This work demonstrates the potential importance of time-dependent aggregation processes on nanoparticle mobility and provides a numerical model capable of capturing/describing these interactions in water-saturated porous media. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. A mathematical model of algae growth in a pelagic-benthic coupled shallow aquatic ecosystem.

    PubMed

    Zhang, Jimin; Shi, Junping; Chang, Xiaoyuan

    2018-04-01

    A coupled system of ordinary differential equations and partial differential equations is proposed to describe the interaction of pelagic algae, benthic algae and one essential nutrient in an oligotrophic shallow aquatic ecosystem with ample supply of light. The existence and uniqueness of non-negative steady states are completely determined for all possible parameter range, and these results characterize sharp threshold conditions for the regime shift from extinction to coexistence of pelagic and benthic algae. The influence of environmental parameters on algal biomass density is also considered, which is an important indicator of algal blooms. Our studies suggest that the nutrient recycling from loss of algal biomass may be an important factor in the algal blooms process; and the presence of benthic algae may limit the pelagic algal biomass density as they consume common resources even if the sediment nutrient level is high.

  14. Green synthesis, characterization and catalytic activity of the Pd/TiO2 nanoparticles for the ligand-free Suzuki-Miyaura coupling reaction.

    PubMed

    Nasrollahzadeh, Mahmoud; Sajadi, S Mohammad

    2016-03-01

    A green synthesis process was developed for production of the Pd/TiO2 nanoparticles (NPs) without using toxic, hazardous and dangerous materials. Myrtus communis L. leaf extract serves as a mild, renewable and non-toxic reducing agent. The advantages of this biosynthesis method include use of cheap, clean, nontoxic and environmentally benign precursors and simple procedures without time-consuming polymerization and problems with treatment of a highly viscous polymeric resin. More importantly, the synthesized Pd/TiO2 NPs presented excellent catalytic activity for ligand-free Suzuki-Miyaura coupling which could be easily separated from the reaction mixture and reused many times with no loss of activity. Therefore, these properties indicate demonstrative benefits of the catalyst. The Pd/TiO2 NPs was characterized by FESEM, TEM, FT-IR, UV-vis spectroscopy and EDS. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Coupled LC-GC techniques for the characterisation of polycyclic aromatic compounds in fuel materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Askey, S.A.; Holden, K.M.L.; Bartle, K.D.

    1995-12-31

    Exposure to polycyclic aromatic compounds (PAC) has long been identified as of considerable environmental concern. Originating from both natural and anthropogenic sources, many PAC exhibit significant carcinogenic and mutagenic properties. Multi-dimensional chromatographic techniques which provide separation by virtue of chemical class (group-type) or by molecular mass greatly simplifies the analysis of inherently complex fuel materials. In this study, on-line LC-GC techniques in which high resolution gas chromatography (HPLC) have been investigated. Comprehensive characterisation of fuel feedstocks and post-pyrolysis and combustion products was achieved by coupling LC-GC to low resolution ion trap mass spectrometry (ITD-MS) and atomic emission detection (AED). Themore » identification of PAC in diesel and coal materials, as well as urban air and diesel exhaust particulate extracts has provided valuable insight into the source, formation and distribution of such compounds pre- and post processing.« less

  16. Enzyme Histochemistry for Functional Histology in Invertebrates.

    PubMed

    Cima, Francesca

    2017-01-01

    In invertebrates, enzyme histochemistry has recently found a renaissance regarding its applications in morphology and ecology. Many enzyme activities are useful for the morphofunctional characterization of cells, as biomarkers of biological and pathologic processes, and as markers of the response to environmental stressors. Here, the adjustments to classic techniques, including the most common enzymes used for digestion, absorption, transport, and oxidation, as well as techniques for azo-coupling, metal salt substitution and oxidative coupling polymerization, are presented in detail for various terrestrial and aquatic invertebrates. This chapter also provides strategies to solve the problems regarding anesthesia, small body size, the presence of an exo- or endoskeleton and the search for the best fixative in relation to the internal fluid osmolarity. These techniques have the aim of obtaining good results for both the pre- and post-embedding labeling of specimens, tissue blocks, sections, and hemolymph smears using both light and transmission electron microscopy.

  17. Low power, compact charge coupled device signal processing system

    NASA Technical Reports Server (NTRS)

    Bosshart, P. W.; Buss, D. D.; Eversole, W. L.; Hewes, C. R.; Mayer, D. J.

    1980-01-01

    A variety of charged coupled devices (CCDs) for performing programmable correlation for preprocessing environmental sensor data preparatory to its transmission to the ground were developed. A total of two separate ICs were developed and a third was evaluated. The first IC was a CCD chirp z transform IC capable of performing a 32 point DFT at frequencies to 1 MHz. All on chip circuitry operated as designed with the exception of the limited dynamic range caused by a fixed pattern noise due to interactions between the digital and analog circuits. The second IC developed was a 64 stage CCD analog/analog correlator for performing time domain correlation. Multiplier errors were found to be less than 1 percent at designed signal levels and less than 0.3 percent at the measured smaller levels. A prototype IC for performing time domain correlation was also evaluated.

  18. A sulfur hexafluoride sensor using quantum cascade and CO2 laser-based photoacoustic spectroscopy.

    PubMed

    Rocha, Mila; Sthel, Marcelo; Lima, Guilherme; da Silva, Marcelo; Schramm, Delson; Miklós, András; Vargas, Helion

    2010-01-01

    The increase in greenhouse gas emissions is a serious environmental problem and has stimulated the scientific community to pay attention to the need for detection and monitoring of gases released into the atmosphere. In this regard, the development of sensitive and selective gas sensors has been the subject of several research programs. An important greenhouse gas is sulphur hexafluoride, an almost non-reactive gas widely employed in industrial processes worldwide. Indeed it is estimated that it has a radiative forcing of 0.52 W/m(2). This work compares two photoacoustic spectrometers, one coupled to a CO(2) laser and another one coupled to a Quantum Cascade (QC) laser, for the detection of SF(6). The laser photoacoustic spectrometers described in this work have been developed for gas detection at small concentrations. Detection limits of 20 ppbv for CO(2) laser and 50 ppbv for quantum cascade laser were obtained.

  19. Raising Environmental Awareness among Miners in Iran

    ERIC Educational Resources Information Center

    Mozaffari, Ezatollah

    2013-01-01

    Generation of waste is inevitable but controllable in minerals industry. The aim of this research is to find ways for raising environmental awareness among miners. Miners' attitude towards environmental mining has been investigated. A survey has been done collecting mine managers' point of view coupled with current trend on mine waste management…

  20. Peroxidase-mediated removal of a polychlorinated biphenyl using natural organic matter as the sole cosubstrate.

    PubMed

    Colosi, Lisa M; Burlingame, Daniel J; Huang, Qingguo; Weber, Walter J

    2007-02-01

    Natural organic matter (NOM) of hydroxylated aromatic character can undergo catalyst-mediated self-coupling reactions to form larger molecular aggregates. Indeed, such reactions are central to natural humification processes. Nonhydroxylated persistent aromatic contaminants such as polychlorinated biphenyls (PCBs) are, conversely, inert with respect to such reactions. It is here demonstrated however that significant coincidental coupling and removal of a representative aqueous-phase PCB occurs during horseradish peroxidase (HRP)-catalyzed oxidative coupling reactions of a representative aquatic NOM. Experiments with Suwannee River fulvic acid as a reactive cosubstrate indicate that 2,2'-dichlorobiphenyl (PCB-4) is covalently incorporated into aggregating NOM, likely through fortuitous cross-coupling reactions. To develop a better understanding of potential mechanisms by which the observed phenomenon occurs, two hydroxylated monomeric cosubstrates of known molecular structure, phenol and 4-methoxyphenol, were investigated as alternative cosubstrates. PCB-4 removal appears from these experiments to relate to certain molecular characteristics of the native cosubstrate molecule (reactivity with HRP, favorability for radical attack, and hydrophobicity) and its associated phenoxy radical (stability). The findings reveal potential pathways by which PCBs, and perhaps other polyaromatic contaminants, may be naturally transformed and detoxified in nature. The results further provide a foundation for development of enhanced-humification strategies for remediation of PCB-contaminated environmental systems.

  1. Development of an integrated chemical weather prediction system for environmental applications at meso to global scales: NMMB/BSC-CHEM

    NASA Astrophysics Data System (ADS)

    Jorba, O.; Pérez, C.; Karsten, K.; Janjic, Z.; Dabdub, D.; Baldasano, J. M.

    2009-09-01

    This contribution presents the ongoing developments of a new fully on-line chemical weather prediction system for meso to global scale applications. The modeling system consists of a mineral dust module and a gas-phase chemistry module coupled on-line to a unified global-regional atmospheric driver. This approach allows solving small scale processes and their interactions at local to global scales. Its unified environment maintains the consistency of all the physico-chemical processes involved. The atmospheric driver is the NCEP/NMMB numerical weather prediction model (Janjic and Black, 2007) developed at National Centers for Environmental Prediction (NCEP). It represents an evolution of the operational WRF-NMME model extending from meso to global scales. Its unified non-hydrostatic dynamical core supports regional and global simulations. The Barcelona Supercomputing Center is currently designing and implementing a chemistry transport model coupled online with the new global/regional NMMB. The new modeling system is intended to be a powerful tool for research and to provide efficient global and regional chemical weather forecasts at sub-synoptic and mesoscale resolutions. The online coupling of the chemistry follows the approach similar to that of the mineral dust module already coupled to the atmospheric driver, NMMB/BSC-DUST (Pérez et al., 2008). Chemical species are advected and mixed at the corresponding time steps of the meteorological tracers using the same numerical scheme. Advection is eulerian, positive definite and monotone. The chemical mechanism and chemistry solver is based on the Kinetic PreProcessor KPP (Damian et al., 2002) package with the main purpose of maintaining a wide flexibility when configuring the model. Such approach will allow using a simplified chemical mechanism for global applications or a more complete mechanism for high-resolution local or regional studies. Moreover, it will permit the implementation of a specific configuration for forecasting applications in regional or global domains. An emission process allows the coupling of different emission inventories sources such as RETRO, EDGAR and GEIA for the global domain, EMEP for Europe and HERMES for Spain. The photolysis scheme is based on the Fast-J scheme, coupled with physics of each model layer (e.g., aerosols, clouds, absorbers as ozone) and it considers grid-scale clouds from the atmospheric driver. The dry deposition scheme follows the deposition velocity analogy for gases, enabling the calculation of deposition fluxes from airborne concentrations. No cloud-chemistry processes are included in the system yet (no wet deposition, scavenging and aqueous chemistry). The modeling system developments will be presented and first results of the gas-phase chemistry at global scale will be discussed. REFERENCES Janjic, Z.I., and Black, T.L., 2007. An ESMF unified model for a broad range of spatial and temporal scales, Geophysical Research Abstracts, 9, 05025. Pérez, C., Haustein, K., Janjic, Z.I., Jorba, O., Baldasano, J.M., Black, T.L., and Nickovic, S., 2008. An online dust model within the meso to global NMMB: current progress and plans. AGU Fall Meeting, San Francisco, A41K-03, 2008. Damian, V., Sandu, A., Damian, M., Potra, F., and Carmichael, G.R., 2002. The kinetic preprocessor KPP - A software environment for solving chemical kinetics. Comp. Chem. Eng., 26, 1567-1579. Sandu, A., and Sander, R., 2006. Technical note:Simulating chemical systems in Fortran90 and Matlab with the Kinetic PreProcessor KPP-2.1. Atmos. Chem. and Phys., 6, 187-195.

  2. Automated collection and processing of environmental samples

    DOEpatents

    Troyer, Gary L.; McNeece, Susan G.; Brayton, Darryl D.; Panesar, Amardip K.

    1997-01-01

    For monitoring an environmental parameter such as the level of nuclear radiation, at distributed sites, bar coded sample collectors are deployed and their codes are read using a portable data entry unit that also records the time of deployment. The time and collector identity are cross referenced in memory in the portable unit. Similarly, when later recovering the collector for testing, the code is again read and the time of collection is stored as indexed to the sample collector, or to a further bar code, for example as provided on a container for the sample. The identity of the operator can also be encoded and stored. After deploying and/or recovering the sample collectors, the data is transmitted to a base processor. The samples are tested, preferably using a test unit coupled to the base processor, and again the time is recorded. The base processor computes the level of radiation at the site during exposure of the sample collector, using the detected radiation level of the sample, the delay between recovery and testing, the duration of exposure and the half life of the isotopes collected. In one embodiment, an identity code and a site code are optically read by an image grabber coupled to the portable data entry unit.

  3. Rapid classification of heavy metal-exposed freshwater bacteria by infrared spectroscopy coupled with chemometrics using supervised method

    NASA Astrophysics Data System (ADS)

    Gurbanov, Rafig; Gozen, Ayse Gul; Severcan, Feride

    2018-01-01

    Rapid, cost-effective, sensitive and accurate methodologies to classify bacteria are still in the process of development. The major drawbacks of standard microbiological, molecular and immunological techniques call for the possible usage of infrared (IR) spectroscopy based supervised chemometric techniques. Previous applications of IR based chemometric methods have demonstrated outstanding findings in the classification of bacteria. Therefore, we have exploited an IR spectroscopy based chemometrics using supervised method namely Soft Independent Modeling of Class Analogy (SIMCA) technique for the first time to classify heavy metal-exposed bacteria to be used in the selection of suitable bacteria to evaluate their potential for environmental cleanup applications. Herein, we present the powerful differentiation and classification of laboratory strains (Escherichia coli and Staphylococcus aureus) and environmental isolates (Gordonia sp. and Microbacterium oxydans) of bacteria exposed to growth inhibitory concentrations of silver (Ag), cadmium (Cd) and lead (Pb). Our results demonstrated that SIMCA was able to differentiate all heavy metal-exposed and control groups from each other with 95% confidence level. Correct identification of randomly chosen test samples in their corresponding groups and high model distances between the classes were also achieved. We report, for the first time, the success of IR spectroscopy coupled with supervised chemometric technique SIMCA in classification of different bacteria under a given treatment.

  4. Accurate quantification of creatinine in serum by coupling a measurement standard to extractive electrospray ionization mass spectrometry

    NASA Astrophysics Data System (ADS)

    Huang, Keke; Li, Ming; Li, Hongmei; Li, Mengwan; Jiang, You; Fang, Xiang

    2016-01-01

    Ambient ionization (AI) techniques have been widely used in chemistry, medicine, material science, environmental science, forensic science. AI takes advantage of direct desorption/ionization of chemicals in raw samples under ambient environmental conditions with minimal or no sample preparation. However, its quantitative accuracy is restricted by matrix effects during the ionization process. To improve the quantitative accuracy of AI, a matrix reference material, which is a particular form of measurement standard, was coupled to an AI technique in this study. Consequently the analyte concentration in a complex matrix can be easily quantified with high accuracy. As a demonstration, this novel method was applied for the accurate quantification of creatinine in serum by using extractive electrospray ionization (EESI) mass spectrometry. Over the concentration range investigated (0.166 ~ 1.617 μg/mL), a calibration curve was obtained with a satisfactory linearity (R2 = 0.994), and acceptable relative standard deviations (RSD) of 4.6 ~ 8.0% (n = 6). Finally, the creatinine concentration value of a serum sample was determined to be 36.18 ± 1.08 μg/mL, which is in excellent agreement with the certified value of 35.16 ± 0.39 μg/mL.

  5. Biofuels from microalgae.

    PubMed

    Li, Yanqun; Horsman, Mark; Wu, Nan; Lan, Christopher Q; Dubois-Calero, Nathalie

    2008-01-01

    Microalgae are a diverse group of prokaryotic and eukaryotic photosynthetic microorganisms that grow rapidly due to their simple structure. They can potentially be employed for the production of biofuels in an economically effective and environmentally sustainable manner. Microalgae have been investigated for the production of a number of different biofuels including biodiesel, bio-oil, bio-syngas, and bio-hydrogen. The production of these biofuels can be coupled with flue gas CO2 mitigation, wastewater treatment, and the production of high-value chemicals. Microalgal farming can also be carried out with seawater using marine microalgal species as the producers. Developments in microalgal cultivation and downstream processing (e.g., harvesting, drying, and thermochemical processing) are expected to further enhance the cost-effectiveness of the biofuel from microalgae strategy.

  6. An expanding universe of circadian networks in higher plants.

    PubMed

    Pruneda-Paz, Jose L; Kay, Steve A

    2010-05-01

    Extensive circadian clock networks regulate almost every biological process in plants. Clock-controlled physiological responses are coupled with daily oscillations in environmental conditions resulting in enhanced fitness and growth vigor. Identification of core clock components and their associated molecular interactions has established the basic network architecture of plant clocks, which consists of multiple interlocked feedback loops. A hierarchical structure of transcriptional feedback overlaid with regulated protein turnover sets the pace of the clock and ultimately drives all clock-controlled processes. Although originally described as linear entities, increasing evidence suggests that many signaling pathways can act as both inputs and outputs within the overall network. Future studies will determine the molecular mechanisms involved in these complex regulatory loops. 2010 Elsevier Ltd. All rights reserved.

  7. Near net shape processing: A necessity for advanced materials applications

    NASA Technical Reports Server (NTRS)

    Kuhn, Howard A.

    1993-01-01

    High quality discrete parts are the backbones for successful operation of equipment used in transportation, communication, construction, manufacturing, and appliances. Traditional shapemaking for discrete parts is carried out predominantly by machining, or removing unwanted material to produce the desired shape. As the cost and complexity of modern materials escalates, coupled with the expense and environmental hazards associated with handling of scrap, it is increasingly important to develop near net shape processes for these materials. Such processes involve casting of liquid materials, consolidation of powder materials, or deformation processing of simple solid shapes into the desired shape. Frequently, several of these operations may be used in sequence to produce a finished part. The processes for near net shape forming may be applied to any type of material, including metals, polymers, ceramics, and their composites. The ability to produce shapes is the key to implementation of laboratory developments in materials science into real world applications. This seminar presents an overview of near net shapemaking processes, some application examples, current developments, and future research opportunities.

  8. Strategic environmental assessment in Hong Kong.

    PubMed

    Ng, Kay Leng; Obbard, Jeffrey Philip

    2005-05-01

    This review examines the development and application of strategic environmental assessment (SEA) process in the planning framework of Hong Kong. Two strategic planning case studies are evaluated within the context of SEA, namely the Territorial Development Strategy Review (TDS Review) and the Third Comprehensive Transport Study (CTS-3). Rapid population growth and urbanisation in Hong Kong, coupled with a historic lack of planning controls and inherent conflicts between government departments have been major obstacles to achieving sustainable development in the territory. Despite these challenges, Hong Kong was one of the first Asian countries to apply SEA to major development plans, where the implementation of the 'SUSDEV 21' study on sustainable development has demonstrated the government's commitment towards integrated environmental protection. The application of SEA has provided decision-makers with key information on potential environment impacts arising from proposed developments, resulting in greater accountability and transparency in the decision-making process. SEA in Hong Kong has also prompted an increased level of environmental awareness and co-operation between government departments and agencies responsible for the management of Hong Kong's natural and urban environments. However, the application of SEA in Hong Kong continues to have notable limitations. SEA needs to evolve beyond its current sectoral application to examine ways in which development decisions can not only pre-empt and prevent environmental damage, but also positively enhance and restore existing natural resources. Current land use plans and transportation strategies still largely determine the pattern of development in the near future without adequate longer-term environmental cost-benefit analysis. Sustainable development includes environmental, social and economic considerations, and these inter-related elements need be suitably balanced. SEA is not a means to obstruct development in Hong Kong, but should be recognised for its inherent socio-economic and ecological value, and fully integrated with the decision-making process. Whilst it is admirable that Hong Kong has taken positive steps in this direction, it is now an opportune moment for the government to have the foresight and tenacity to create a sustainable development framework for Hong Kong into the future.

  9. Research approach to teaching groundwater biodegradation in karst aquifers

    USGS Publications Warehouse

    King, L.; Byl, T.; Painter, R.

    2006-01-01

    TSU in partnership with the USGS has conducted extensive research regarding biode??gradation of contaminants in karst aquifers. This research resulted in the development of a numerical approach to modeling biodegradation of contaminants in karst aquifers that is taught to environmental engineering students in several steps. First, environmental engineering students are taught chemical-reaction engineering principles relating to a wide variety of environmental fate and transport issues. Second, as part of TSU's engineering course curriculum, students use a non-ideal flow laboratory reactor system and run a tracer study to establish residence time distribution (RTD). Next, the students couple that formula to a first-order biodegradation rate and predict the removal of a biodegradable contaminant as a function of residence time. Following this, students are shown data collected from karst bedrock wells that suggest that karst aquifers are analogous to non-ideal flow reactors. The students are challenged to develop rates of biodegradation through lab studies and use their results to predict biodegradaton at an actual contaminated karst site. Field studies are also conducted to determine the accuracy of the students' predictions. This academic approach teaches biodegradation processes, rate-kinetic processes, hydraulic processes and numerical principles. The students are able to experience how chemical engineering principles can be applied to other situations, such as, modeling biodegradation of contaminants in karst aquifers. This paper provides background on the chemical engineering principles and karst issues used in the research-enhanced curriculum. ?? American Society for Engineering Education, 2006.

  10. Exergy: its potential and limitations in environmental science and technology.

    PubMed

    Dewulf, Jo; Van Langenhove, Herman; Muys, Bart; Bruers, Stijn; Bakshi, Bhavik R; Grubb, Geoffrey F; Paulus, D M; Sciubba, Enrico

    2008-04-01

    New technologies, either renewables-based or not, are confronted with both economic and technical constraints. Their development takes advantage of considering the basic laws of economics and thermodynamics. With respect to the latter, the exergy concept pops up. Although its fundamentals, that is, the Second Law of Thermodynamics, were already established in the 1800s, it is only in the last years that the exergy concept has gained a more widespread interest in process analysis, typically employed to identify inefficiencies. However, exergy analysis today is implemented far beyond technical analysis; it is also employed in environmental, (thermo)economic, and even sustainability analysis of industrial systems. Because natural ecosystems are also subjected to the basic laws of thermodynamics, it is another subject of exergy analysis. After an introduction on the concept itself, this review focuses on the potential and limitations of the exergy conceptin (1) ecosystem analysis, utilized to describe maximum storage and maximum dissipation of energy flows (2); industrial system analysis: from single process analysis to complete process chain analysis (3); (thermo)economic analysis, with extended exergy accounting; and (4) environmental impact assessment throughout the whole life cycle with quantification of the resource intake and emission effects. Apart from technical system analysis, it proves that exergy as a tool in environmental impact analysis may be the most mature field of application, particularly with respect to resource and efficiency accounting, one of the major challenges in the development of sustainable technology. Far less mature is the exergy analysis of natural ecosystems and the coupling with economic analysis, where a lively debate is presently going on about the actual merits of an exergy-based approach.

  11. Process analysis of a molten carbonate fuel cell power plant fed with a biomass syngas

    NASA Astrophysics Data System (ADS)

    Tomasi, C.; Baratieri, M.; Bosio, B.; Arato, E.; Baggio, P.

    The coupling of renewable energy sources and innovative power generation technologies is of topical interest to meet demands for increased power generation and cleaner environmental performance. Accordingly, biomass is receiving considerable attention as a partial substitute for fossil fuels, as it is more environmentally friendly and provides a profitable way of disposing of waste. In addition, fuel cells are perceived as most promising electrical power generation systems. Today, many plants combining these two concepts are under study; they differ in terms of biomass type and/or power plant configuration. Even if the general feasibility of such applications has been demonstrated, there are still many associated problems to be resolved. This study examines a plant configuration based on a molten carbonate fuel cell (MCFC) and a recirculated fluidized-bed reactor which has been applied to the thermal conversion of many types of biomass. Process analysis is conducted by simulating the entire plant using a commercial code. In particular, an energy assessment is studied by taking account of the energy requirements of auxiliary equipment and the possibility of utilizing the exhaust gases for cogeneration.

  12. Satellite based hydroclimatic understanding of evolution of Dengue and Zika virus

    NASA Astrophysics Data System (ADS)

    Khan, R.; Jutla, A.; Colwell, R. R.

    2017-12-01

    Vector-borne diseases are prevalent in tropical and subtropical regions especially in Africa, South America, and Asia. Vector eradication is perhaps not possible since pathogens adapt to local environment. In absence of appropriate vaccinations for Dengue and Zika virus, burden of these two infections continue to increase in several geographical locations. Aedes spp. is one of the major vectors for Dengue and Zika viruses. Etiologies on Dengue and Zika viruses are evolving, however the key question remains as to how one species of mosquito can transmit two different infections? We argue that a set of conducive environmental condition, modulated by regional climatic and weather processes, may lead to abundance of a specific virus. Using satellite based rainfall (TRMM/GPM), land surface temperature (MODIS) and dew point temperature (AIRS/MERRA), we have identified appropriate thresholds that can provide estimate on risk of abundance of Dengue or Zika viruses at least few weeks in advance. We will discuss a framework coupling satellite derived hydroclimatic and societal processes to predict environmental niches of favorability of conditions of Dengue or Zika risk in human population on a global scale.

  13. Coupled hydrologic and land use change models for decision making on land and water resources in the Upper Blue Nile basin

    NASA Astrophysics Data System (ADS)

    Yalew, Seleshi; van der Zaag, Pieter; Mul, Marloes; Uhlenbrook, Stefan; Teferi, Ermias; van Griensven, Ann; van der Kwast, Johannes

    2013-04-01

    Hydrology of a basin, alongside climate change, is well documented to impact and to be impacted by land use/land cover change processes. The need to understand the impacts of hydrology on land use change and vice- versa cannot be overstated especially in basins such as the Upper Blue Nile in Ethiopia, where the vast majority of farmers depend on rain-fed agriculture. A slight fluctuation in rainy seasons or an increase or decrease in magnitude of precipitation can easily trigger drought or flooding. On the other hand, ever growing population and emerging economic development, among others, is likely to continually alter land use/land cover change, thereby affecting hydrological processes. With the intention of identifying and analyzing interactions and future scenarios of the hydrology and land use/land cover, we carried out a case study on a meso-scale catchment, in the Upper Blue Nile basin. A land use model using SITE (SImulation of Terrestrial Environments) was built for analyzing land use trends from aerial land cover photographs of 1957 and simulate until 2009 based on socio-economic as well as biophysical factors. Major land use drivers in the catchment were identified and used as input to the land use model. Separate land use maps were produced using Landsat images of 1972, 1986, 1994 and 2009 for historical calibration of the land use model. By the same token, a hydrological model for the same catchment was built using the SWAT (Soil and Water Assessment Tool) model. After calibration of the two independent models, they were loosely coupled for analyzing the changes in either of the models and impacts on the other. Among other details, the coupled model performed better in identifying limiting factors from both the hydrology as well as from the land use perspectives. For instance, the simulation of the uncoupled land use model alone (without inputs from SWAT on the water budget of each land use parcel) continually considered a land use type such as a wet land/marsh land, simply as a wetland until the simulation period finishes. The wetland or the marsh land, which is not crop friendly in the location, does not get allocated to any other land use such as for certain crop types or settlement, because the land use model cannot tell how much water is added to or drained from each parcel every season. However, the simulation feedback from the coupled hydrological model shows that certain wetland/marsh land parcels, in fact, hold less and less water or even dry up during the simulation period, thereby putting themselves as a good candidate to be picked by the land use model in a next time step and to be allocated to other land use types. The same way, a measure in the land use aspect, which considers socio-economic as well as biophysical driving forces of in the catchment, shows changes in runoff and sedimentation levels in SWAT model outputs. The results of a future scenario considering the continuing population growth projects that about 35% of the wetland dries up and gets converted to cultivation by 2020. This study emphasizes the importance of identifying possible impacts of the future hydrology on other components of the socio-environmental systems and contrariwise during environmental decision making, especially in areas where a relatively small change may have large impacts (such flood and/or drought prone basins as the Nile). The study also demonstrates a sound methodology for assessing the impact of land use change on hydrology and vice-versa by dynamically exchanging data through feedback mechanisms (coupling socio-environmental and hydrological models) which lead to a better understanding of socio-environmental problems. Keywords: Coupling, socio-environment, Nile, land use models, hydrological models

  14. Three-Dimensional Model of Heat and Mass Transfer in Fractured Rocks to Estimate Environmental Conditions Along Heated Drifts

    NASA Astrophysics Data System (ADS)

    Fedors, R. W.; Painter, S. L.

    2004-12-01

    Temperature gradients along the thermally-perturbed drifts of the potential high-level waste repository at Yucca Mountain, Nevada, will drive natural convection and associated heat and mass transfer along drifts. A three-dimensional, dual-permeability, thermohydrological model of heat and mass transfer was used to estimate the magnitude of temperature gradients along a drift. Temperature conditions along heated drifts are needed to support estimates of repository-edge cooling and as input to computational fluid dynamics modeling of in-drift axial convection and the cold-trap process. Assumptions associated with abstracted heat transfer models and two-dimensional thermohydrological models weakly coupled to mountain-scale thermal models can readily be tested using the three-dimensional thermohydrological model. Although computationally expensive, the fully coupled three-dimensional thermohydrological model is able to incorporate lateral heat transfer, including host rock processes of conduction, convection in gas phase, advection in liquid phase, and latent-heat transfer. Results from the three-dimensional thermohydrological model showed that weakly coupling three-dimensional thermal and two-dimensional thermohydrological models lead to underestimates of temperatures and underestimates of temperature gradients over large portions of the drift. The representative host rock thermal conductivity needed for abstracted heat transfer models are overestimated using the weakly coupled models. If axial flow patterns over large portions of drifts are not impeded by the strong cross-sectional flow patterns imparted by the heat rising directly off the waste package, condensation from the cold-trap process will not be limited to the extreme ends of each drift. Based on the three-dimensional thermohydrological model, axial temperature gradients occur sooner over a larger portion of the drift, though high gradients nearest the edge of the potential repository are dampened. This abstract is an independent product of CNWRA and does not necessarily reflect the view or regulatory position of the Nuclear Regulatory Commission.

  15. Coupling Satellite Data with Species Distribution and Connectivity Models as a Tool for Environmental Management and Planning in Matrix-Sensitive Species.

    PubMed

    Rödder, Dennis; Nekum, Sven; Cord, Anna F; Engler, Jan O

    2016-07-01

    Climate change and anthropogenic habitat fragmentation are considered major threats for global biodiversity. As a direct consequence, connectivity is increasingly disrupted in many species, which might have serious consequences that could ultimately lead to the extinction of populations. Although a large number of reserves and conservation sites are designated and protected by law, potential habitats acting as inter-population connectivity corridors are, however, mostly ignored in the common practice of environmental planning. In most cases, this is mainly caused by a lack of quantitative measures of functional connectivity available for the planning process. In this study, we highlight the use of fine-scale potential connectivity models (PCMs) derived from multispectral satellite data for the quantification of spatially explicit habitat corridors for matrix-sensitive species of conservation concern. This framework couples a species distribution model with a connectivity model in a two-step framework, where suitability maps from step 1 are transformed into maps of landscape resistance in step 2 filtered by fragmentation thresholds. We illustrate the approach using the sand lizard (Lacerta agilis L.) in the metropolitan area of Cologne, Germany, as a case study. Our model proved to be well suited to identify connected as well as completely isolated populations within the study area. Furthermore, due to its fine resolution, the PCM was also able to detect small linear structures known to be important for sand lizards' inter-population connectivity such as railroad embankments. We discuss the applicability and possible implementation of PCMs to overcome shortcomings in the common practice of environmental impact assessments.

  16. Metal(loid) levels in biological matrices from human populations exposed to mining contamination--Panasqueira Mine (Portugal).

    PubMed

    Coelho, Patrícia; Costa, Solange; Silva, Susana; Walter, Alan; Ranville, James; Sousa, Ana C A; Costa, Carla; Coelho, Marta; García-Lestón, Julia; Pastorinho, M Ramiro; Laffon, Blanca; Pásaro, Eduardo; Harrington, Chris; Taylor, Andrew; Teixeira, João Paulo

    2012-01-01

    Mining activities may affect the health of miners and communities living near mining sites, and these health effects may persist even when the mine is abandoned. During mining processes various toxic wastes are produced and released into the surrounding environment, resulting in contamination of air, drinking water, rivers, plants, and soils. In a geochemical sampling campaign undertaken in the Panasqueira Mine area of central Portugal, an anomalous distribution of several metals and arsenic (As) was identified in various environmental media. Several potentially harmful elements, including As, cadmium (Cd), chromium (Cr), manganese (Mn), nickel (Ni), lead (Pb), and selenium (Se), were quantified in blood, urine, hair, and nails (toe and finger) from a group of individuals living near the Panasqueira Mine who were environmentally and occupationally exposed. A group with similar demographic characteristics without known exposure to mining activities was also compared. Genotoxicity was evaluated by means of T-cell receptor (TCR) mutation assay, and percentages of different lymphocyte subsets were selected as immunotoxicity biomarkers. Inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis showed elevated levels of As, Cd, Cr, Mn, and Pb in all biological samples taken from populations living close to the mine compared to controls. Genotoxic and immunotoxic differences were also observed. The results provide evidence of an elevated potential risk to the health of populations, with environmental and occupational exposures resulting from mining activities. Further, the results emphasize the need to implement preventive measures, remediation, and rehabilitation plans for the region.

  17. Modelling human decision-making in coupled human and natural systems

    NASA Astrophysics Data System (ADS)

    Feola, G.

    2012-12-01

    A solid understanding of human decision-making is essential to analyze the complexity of coupled human and natural systems (CHANS) and inform policies to promote resilience in the face of environmental change. Human decisions drive and/or mediate the interactions and feedbacks, and contribute to the heterogeneity and non-linearity that characterize CHANS. However, human decision-making is usually over-simplistically modeled, whereby human agents are represented deterministically either as dumb or clairvoyant decision-makers. Decision-making models fall short in the integration of both environmental and human behavioral drivers, and concerning the latter, tend to focus on only one category, e.g. economic, cultural, or psychological. Furthermore, these models render a linear decision-making process and therefore fail to account for the recursive co-evolutionary dynamics in CHANS. As a result, these models constitute only a weak basis for policy-making. There is therefore scope and an urgent need for better approaches to human decision-making, to produce the knowledge that can inform vulnerability reduction policies in the face of environmental change. This presentation synthesizes the current state-of-the-art of modelling human decision-making in CHANS, with particular reference to agricultural systems, and delineates how the above mentioned shortcomings can be overcome. Through examples from research on pesticide use and adaptation to climate change, both based on the integrative agent-centered framework (Feola and Binder, 2010), the approach for an improved understanding of human agents in CHANS are illustrated. This entails: integrative approach, focus on behavioral dynamics more than states, feedbacks between individual and system levels, and openness to heterogeneity.

  18. Coupling Satellite Data with Species Distribution and Connectivity Models as a Tool for Environmental Management and Planning in Matrix-Sensitive Species

    NASA Astrophysics Data System (ADS)

    Rödder, Dennis; Nekum, Sven; Cord, Anna F.; Engler, Jan O.

    2016-07-01

    Climate change and anthropogenic habitat fragmentation are considered major threats for global biodiversity. As a direct consequence, connectivity is increasingly disrupted in many species, which might have serious consequences that could ultimately lead to the extinction of populations. Although a large number of reserves and conservation sites are designated and protected by law, potential habitats acting as inter-population connectivity corridors are, however, mostly ignored in the common practice of environmental planning. In most cases, this is mainly caused by a lack of quantitative measures of functional connectivity available for the planning process. In this study, we highlight the use of fine-scale potential connectivity models (PCMs) derived from multispectral satellite data for the quantification of spatially explicit habitat corridors for matrix-sensitive species of conservation concern. This framework couples a species distribution model with a connectivity model in a two-step framework, where suitability maps from step 1 are transformed into maps of landscape resistance in step 2 filtered by fragmentation thresholds. We illustrate the approach using the sand lizard ( Lacerta agilis L.) in the metropolitan area of Cologne, Germany, as a case study. Our model proved to be well suited to identify connected as well as completely isolated populations within the study area. Furthermore, due to its fine resolution, the PCM was also able to detect small linear structures known to be important for sand lizards' inter-population connectivity such as railroad embankments. We discuss the applicability and possible implementation of PCMs to overcome shortcomings in the common practice of environmental impact assessments.

  19. Online coupled regional meteorology-chemistry models in Europe: current status and prospects

    NASA Astrophysics Data System (ADS)

    Baklanov, A.; Schluenzen, K. H.; Suppan, P.; Baldasano, J.; Brunner, D.; Aksoyoglu, S.; Carmichael, G.; Douros, J.; Flemming, J.; Forkel, R.; Galmarini, S.; Gauss, M.; Grell, G.; Hirtl, M.; Joffre, S.; Jorba, O.; Kaas, E.; Kaasik, M.; Kallos, G.; Kong, X.; Korsholm, U.; Kurganskiy, A.; Kushta, J.; Lohmann, U.; Mahura, A.; Manders-Groot, A.; Maurizi, A.; Moussiopoulos, N.; Rao, S. T.; Savage, N.; Seigneur, C.; Sokhi, R.; Solazzo, E.; Solomos, S.; Sørensen, B.; Tsegas, G.; Vignati, E.; Vogel, B.; Zhang, Y.

    2013-05-01

    The simulation of the coupled evolution of atmospheric dynamics, pollutant transport, chemical reactions and atmospheric composition is one of the most challenging tasks in environmental modelling, climate change studies, and weather forecasting for the next decades as they all involve strongly integrated processes. Weather strongly influences air quality (AQ) and atmospheric transport of hazardous materials, while atmospheric composition can influence both weather and climate by directly modifying the atmospheric radiation budget or indirectly affecting cloud formation. Until recently, however, due to the scientific complexities and lack of computational power, atmospheric chemistry and weather forecasting have developed as separate disciplines, leading to the development of separate modelling systems that are only loosely coupled. The continuous increase in computer power has now reached a stage that enables us to perform online coupling of regional meteorological models with atmospheric chemical transport models. The focus on integrated systems is timely, since recent research has shown that meteorology and chemistry feedbacks are important in the context of many research areas and applications, including numerical weather prediction (NWP), AQ forecasting as well as climate and Earth system modelling. However, the relative importance of online integration and its priorities, requirements and levels of detail necessary for representing different processes and feedbacks can greatly vary for these related communities: (i) NWP, (ii) AQ forecasting and assessments, (iii) climate and earth system modelling. Additional applications are likely to benefit from online modelling, e.g.: simulation of volcanic ash or forest fire plumes, pollen warnings, dust storms, oil/gas fires, geo-engineering tests involving changes in the radiation balance. The COST Action ES1004 - European framework for online integrated air quality and meteorology modelling (EuMetChem) - aims at paving the way towards a new generation of online integrated atmospheric chemical transport and meteorology modelling with two-way interactions between different atmospheric processes including dynamics, chemistry, clouds, radiation, boundary layer and emissions. As its first task, we summarise the current status of European modelling practices and experience with online coupled modelling of meteorology with atmospheric chemistry including feedback mechanisms and attempt reviewing the various issues connected to the different modules of such online coupled models but also providing recommendations for coping with them for the benefit of the modelling community at large.

  20. Coupling landscape water storage and supplemental irrigation to increase productivity and improve environmental stewardship in the US Midwest

    USDA-ARS?s Scientific Manuscript database

    Agriculture must expand production for a growing population while simultaneously reducing its environmental impacts. These goals need not be in tension with one another. Here we outline a vision for improving both the productivity and environmental performance of agriculture in the US Corn Belt. Mea...

  1. A Generalized Hybrid Multiscale Modeling Approach for Flow and Reactive Transport in Porous Media

    NASA Astrophysics Data System (ADS)

    Yang, X.; Meng, X.; Tang, Y. H.; Guo, Z.; Karniadakis, G. E.

    2017-12-01

    Using emerging understanding of biological and environmental processes at fundamental scales to advance predictions of the larger system behavior requires the development of multiscale approaches, and there is strong interest in coupling models at different scales together in a hybrid multiscale simulation framework. A limited number of hybrid multiscale simulation methods have been developed for subsurface applications, mostly using application-specific approaches for model coupling. The proposed generalized hybrid multiscale approach is designed with minimal intrusiveness to the at-scale simulators (pre-selected) and provides a set of lightweight C++ scripts to manage a complex multiscale workflow utilizing a concurrent coupling approach. The workflow includes at-scale simulators (using the lattice-Boltzmann method, LBM, at the pore and Darcy scale, respectively), scripts for boundary treatment (coupling and kriging), and a multiscale universal interface (MUI) for data exchange. The current study aims to apply the generalized hybrid multiscale modeling approach to couple pore- and Darcy-scale models for flow and mixing-controlled reaction with precipitation/dissolution in heterogeneous porous media. The model domain is packed heterogeneously that the mixing front geometry is more complex and not known a priori. To address those challenges, the generalized hybrid multiscale modeling approach is further developed to 1) adaptively define the locations of pore-scale subdomains, 2) provide a suite of physical boundary coupling schemes and 3) consider the dynamic change of the pore structures due to mineral precipitation/dissolution. The results are validated and evaluated by comparing with single-scale simulations in terms of velocities, reactive concentrations and computing cost.

  2. Quantum nonunital dynamics of spin-bath-assisted Fisher information

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hao, Xiang, E-mail: haoxiang-edu198126@163.com; Wu, Yinzhong

    2016-04-15

    The nonunital non-Markovian dynamics of qubits immersed in a spin bath is studied without any Markovian approximation. The environmental effects on the precisions of quantum parameter estimation are taken into account. The time-dependent transfer matrix and inhomogeneity vector are obtained for the description of the open dynamical process. The dynamical behaviour of one qubit coupled to a spin bath is geometrically described by the Bloch vector. It is found out that the nonunital non-Markovian effects can engender the improvement of the precision of quantum parameter estimation. This result contributes to the environment-assisted quantum information theory.

  3. Membrane Protein Structure, Function, and Dynamics: a Perspective from Experiments and Theory

    DOE PAGES

    Cournia, Zoe; Allen, Toby W.; Andricioaei, Ioan; ...

    2015-06-11

    It is fundamental for the flourishing biological cells that membrane proteins mediate the process. Membrane-embedded transporters move ions and larger solutes across membranes; receptors mediate communication between the cell and its environment and membrane-embedded enzymes catalyze chemical reactions. Understanding these mechanisms of action requires knowledge of how the proteins couple to their fluid, hydrated lipid membrane environment. Here, we present here current studies in computational and experimental membrane protein biophysics, and show how they address outstanding challenges in understanding the complex environmental effects on the structure, function, and dynamics of membrane proteins.

  4. Copper-catalyzed aerobic oxidative N-S bond functionalization for C-S bond formation: regio- and stereoselective synthesis of sulfones and thioethers.

    PubMed

    Li, Xianwei; Xu, Yanli; Wu, Wanqing; Jiang, Chang; Qi, Chaorong; Jiang, Huanfeng

    2014-06-23

    A regio- and stereoselective synthesis of sulfones and thioethers by means of Cu(I)-catalyzed aerobic oxidative N-S bond cleavage of sulfonyl hydrazides, followed by cross-coupling reactions with alkenes and aromatic compounds to form the C sp 2-S bond, is described herein. N2 and H2O are the byproducts of this transformation, thus offering an environmentally benign process with a wide range of potential applications in organic synthesis and medicinal chemistry. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Evaluation of Environmental Effects of Wave Energy Convertor Arrays

    NASA Astrophysics Data System (ADS)

    Jones, C. A.

    2015-12-01

    Stakeholders and regulators in the U.S. are generally uncertain as to the potential environmental impacts posed by deployments of marine and hydrokinetic (MHK) devices, and in particular wave energy conversion (WEC) devices, in coastal waters. The first pilot-scale WEC deployments in the U.S. have had to absorb unsustainable costs and delays associated with permitting to get devices in the water. As such, there is an urgent industry need to streamline the technical activities and processes used to assess potential environmental impacts. To enable regulators and stakeholders to become more comfortable and confident with developing effective MHK environmental assessments, a better understanding of the potential environmental effects induced by arrays of WEC devices is needed. A key challenge in developing this understanding is that the assessment of the WEC effects must come prior to deployment. A typical approach in similar environmental assessments is to use numerical models to simulate the WEC devices and array layouts so that the appropriate environmental stressors and receptors can be identified and assessed. Sandia National Laboratories (SNL) and the U.S. Department of Energy are fulfilling the industry-wide need to develop "WEC-friendly" open-source numerical modeling tools capable of assessing potential changes to the physical environment caused by the operation of WEC arrays. Studies using these tools will advance the nation's general knowledge of the interrelationships among the number, size, efficiency, and configuration of MHK arrays and the subsequent effects these relationships may have on the deployment environment. By better understanding these relationships, industry, stakeholders, and regulators will be able to work together to optimize WEC deployments such that environmental impacts are minimized while power output is maximized. The present work outlines the initial effort in coupling the SNL WEC-friendly tools with the environmental assessment process. The development of the initial phases of a WEC case study in the offshore waters of Newport, Oregon will be presented. Examples of the quantitative evaluation of changes to important parameters that mau constitute an environmental stressors will be presented.

  6. Transformative environmental governance

    EPA Science Inventory

    Transformative governance is an approach to environmental governance that has the capacity to respond to, manage, and trigger regime shifts in coupled social-ecological systems (SESs) at multiple scales. The goal of transformative governance is to actively shift degraded SESs to ...

  7. Threshold and resilience management of coupled urbanization and water environmental system in the rapidly changing coastal region.

    PubMed

    Li, Yangfan; Li, Yi; Wu, Wei

    2016-01-01

    The concept of thresholds shows important implications for environmental and resource management. Here we derived potential landscape thresholds which indicated abrupt changes in water quality or the dividing points between exceeding and failing to meet national surface water quality standards for a rapidly urbanizing city on the Eastern Coast in China. The analysis of landscape thresholds was based on regression models linking each of the seven water quality variables to each of the six landscape metrics for this coupled land-water system. We found substantial and accelerating urban sprawl at the suburban areas between 2000 and 2008, and detected significant nonlinear relations between water quality and landscape pattern. This research demonstrated that a simple modeling technique could provide insights on environmental thresholds to support more-informed decision making in land use, water environmental and resilience management. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Coping Processes of Couples Experiencing Infertility

    ERIC Educational Resources Information Center

    Peterson, Brennan D.; Newton, Christopher R.; Rosen, Karen H.; Schulman, Robert S.

    2006-01-01

    This study explored the coping processes of couples experiencing infertility. Participants included 420 couples referred for advanced reproductive treatments. Couples were divided into groups based on the frequency of their use of eight coping strategies. Findings suggest that coping processes, which are beneficial to individuals, may be…

  9. Air-Sea Heat Flux Transfer for MJO Initiation Processes during DYNAMO/CINDY2011 in Extended-Range Forecasts

    NASA Astrophysics Data System (ADS)

    Hong, X.; Reynolds, C. A.; Doyle, J. D.

    2016-12-01

    In this study, two-sets of monthly forecasts for the period during the Dynamics of Madden-Julian Oscillation (MJO)/Cooperative Indian Ocean Experiment of Intraseasonal Variability (DAYNAMO/CINDY) in November 2011 are examined. Each set includes three forecasts with the first set from Navy Global Environmental Model (NAVGEM) and the second set from Navy's non-hydrostatic Coupled Ocean-Atmosphere Mesoscale Prediction System (COAMPS®1). Three NAVGEM monthly forecasts have used sea surface temperature (SST) from persistent at the initial time, from Navy Coupled Ocean Data Assimilation (NCODA) analysis, and from coupled NAVGEM-Hybrid Coordinate Ocean Model (HYCOM) forecasts. Examination found that NAVGEM can predict the MJO at 20-days lead time using SST from analysis and from coupled NAVGEM-HYCOM but cannot predict the MJO using the persistent SST, in which a clear circumnavigating signal is absent. Three NAVGEM monthly forecasts are then applied as lateral boundary conditions for three COAMPS monthly forecasts. The results show that all COAMPS runs, including using lateral boundary conditions from the NAVGEM that is without the MJO signal, can predict the MJO. Vertically integrated moisture anomaly and 850-hPa wind anomaly in all COAMPS runs have indicated strong anomalous equatorial easterlies associated with Rossby wave prior to the MJO initiation. Strong surface heat fluxes and turbulence kinetic energy have promoted the convective instability and triggered anomalous ascending motion, which deepens moist boundary layer and develops deep convection into the upper troposphere to form the MJO phase. The results have suggested that air-sea interaction process is important for the initiation and development of the MJO. 1COAMPS® is a registered trademark of the Naval Research Laboratory

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wendt, Fabian F; Damiani, Rick R

    This poster summarizes the scope and preliminary results of a study conducted for the Bureau of Safety and Environmental Enforcement aimed at quantifying differences between two modeling approaches (fully coupled and sequentially coupled) through aero-hydro-servo-elastic simulations of two offshore wind turbines on a monopile and jacket substructure.

  11. Assessing the Impact of Model Parameter Uncertainty in Simulating Grass Biomass Using a Hybrid Carbon Allocation Strategy

    NASA Astrophysics Data System (ADS)

    Reyes, J. J.; Adam, J. C.; Tague, C.

    2016-12-01

    Grasslands play an important role in agricultural production as forage for livestock; they also provide a diverse set of ecosystem services including soil carbon (C) storage. The partitioning of C between above and belowground plant compartments (i.e. allocation) is influenced by both plant characteristics and environmental conditions. The objectives of this study are to 1) develop and evaluate a hybrid C allocation strategy suitable for grasslands, and 2) apply this strategy to examine the importance of various parameters related to biogeochemical cycling, photosynthesis, allocation, and soil water drainage on above and belowground biomass. We include allocation as an important process in quantifying the model parameter uncertainty, which identifies the most influential parameters and what processes may require further refinement. For this, we use the Regional Hydro-ecologic Simulation System, a mechanistic model that simulates coupled water and biogeochemical processes. A Latin hypercube sampling scheme was used to develop parameter sets for calibration and evaluation of allocation strategies, as well as parameter uncertainty analysis. We developed the hybrid allocation strategy to integrate both growth-based and resource-limited allocation mechanisms. When evaluating the new strategy simultaneously for above and belowground biomass, it produced a larger number of less biased parameter sets: 16% more compared to resource-limited and 9% more compared to growth-based. This also demonstrates its flexible application across diverse plant types and environmental conditions. We found that higher parameter importance corresponded to sub- or supra-optimal resource availability (i.e. water, nutrients) and temperature ranges (i.e. too hot or cold). For example, photosynthesis-related parameters were more important at sites warmer than the theoretical optimal growth temperature. Therefore, larger values of parameter importance indicate greater relative sensitivity in adequately representing the relevant process to capture limiting resources or manage atypical environmental conditions. These results may inform future experimental work by focusing efforts on quantifying specific parameters under various environmental conditions or across diverse plant functional types.

  12. Intrinsic Chemiluminescence Generation during Advanced Oxidation of Persistent Halogenated Aromatic Carcinogens.

    PubMed

    Mao, Li; Liu, Yu-Xiang; Huang, Chun-Hua; Gao, Hui-Ying; Kalyanaraman, Balaraman; Zhu, Ben-Zhan

    2015-07-07

    The ubiquitous distribution coupled with their carcinogenicity has raised public concerns on the potential risks to both human health and the ecosystem posed by the halogenated aromatic compounds (XAr). Recently, advanced oxidation processes (AOPs) have been increasingly favored as an "environmentally-green" technology for the remediation of such recalcitrant and highly toxic XAr. Here, we show that AOPs-mediated degradation of the priority pollutant pentachlorophenol and all other XAr produces an intrinsic chemiluminescence that directly depends on the generation of the extremely reactive hydroxyl radicals. We propose that the hydroxyl radical-dependent formation of quinoid intermediates and electronically excited carbonyl species is responsible for this unusual chemiluminescence production. A rapid, sensitive, simple, and effective chemiluminescence method was developed to quantify trace amounts of XAr and monitor their real-time degradation kinetics. These findings may have broad biological and environmental implications for future research on this important class of halogenated persistent organic pollutants.

  13. Transformative environmental governance

    USGS Publications Warehouse

    Chaffin, Brian C.; Garmestani, Ahjond S.; Gunderson, Lance H.; Harm Benson, Melinda; Angeler, David G.; Arnold, Craig Anthony (Tony); Cosens, Barbara; Kundis Craig, Robin; Ruhl, J.B.; Allen, Craig R.

    2016-01-01

    Transformative governance is an approach to environmental governance that has the capacity to respond to, manage, and trigger regime shifts in coupled social-ecological systems (SESs) at multiple scales. The goal of transformative governance is to actively shift degraded SESs to alternative, more desirable, or more functional regimes by altering the structures and processes that define the system. Transformative governance is rooted in ecological theories to explain cross-scale dynamics in complex systems, as well as social theories of change, innovation, and technological transformation. Similar to adaptive governance, transformative governance involves a broad set of governance components, but requires additional capacity to foster new social-ecological regimes including increased risk tolerance, significant systemic investment, and restructured economies and power relations. Transformative governance has the potential to actively respond to regime shifts triggered by climate change, and thus future research should focus on identifying system drivers and leading indicators associated with social-ecological thresholds.

  14. Uncooled tunneling infrared sensor

    NASA Technical Reports Server (NTRS)

    Kenny, Thomas W. (Inventor); Kaiser, William J. (Inventor); Podosek, Judith A. (Inventor); Vote, Erika C. (Inventor); Muller, Richard E. (Inventor); Maker, Paul D. (Inventor)

    1995-01-01

    An uncooled infrared tunneling sensor in which the only moving part is a diaphragm which is deflected into contact with a micromachined silicon tip electrode prepared by a novel lithographic process. Similarly prepared deflection electrodes employ electrostatic force to control the deflection of a silicon nitride, flat diaphragm membrane. The diaphragm exhibits a high resonant frequency which reduces the sensor's sensitivity to vibration. A high bandwidth feedback circuit controls the tunneling current by adjusting the deflection voltage to maintain a constant deflection of the membrane. The resulting infrared sensor can be miniaturized to pixel dimensions smaller than 100 .mu.m. An alternative embodiment is implemented using a corrugated membrane to permit large deflection without complicated clamping and high deflection voltages. The alternative embodiment also employs a pinhole aperture in a membrane to accommodate environmental temperature variation and a sealed chamber to eliminate environmental contamination of the tunneling electrodes and undesireable accoustic coupling to the sensor.

  15. The Multi-Scale Response of Water Quality, Biodiversity and Carbon Sequestration to Coupled Macronutrient Cycling from Source to Sea: TURF2SURF

    NASA Astrophysics Data System (ADS)

    Cosby, B. J., Jr.; Wade, A. J.; Reinsch, S.; Robins, P. E.; Emmett, B.; Jago, C. F.

    2015-12-01

    Turf2Surf is a large, multi-disciplinary project that aims to test the hypothesis that the spatial and temporal patterns of water quality, C sequestration and biodiversity are better explained through the large-scale coupling of C, N and P cycles than by single cycle, single system approaches. To achieve this, a catchment-scale study of the River Conwy (349 km2) in Wales is being done with emphasis on determining when, where and how coupled macronutrient (C, N, P) cycling occurs in the biogeochemical hot-spots of the soils, the riparian zone, instream and in the river-estuarine transition zone. A major integrated measurement programme is now largely complete. New data are being analysed to understand which soil properties have greatest influence on above and below-ground productivity including plant traits and how microbial processing is controlled by stoichiometry and nutrient priming. Within the stream network, new understanding is being produced on the in-river algal and whole ecosystem (metabolic) response to CNP additions and the factors affecting the fate and cycling of organic matter. In the estuary, initial results indicate a subsurface jet is causing stratification and a velocity anomaly has been observed. Both are important in terms of suspended matter transport and floc break-up. An integrated model is being built to describe the soil-atmosphere-vegetation processes which is linked, firstly, to flow and water quality models that describe the CNP flux transport and transformations from the headwaters to the estuary and, secondly, to biodiversity models. The purpose of the integrated model is to quantify how coupled CNP cycles may respond to environmental change and thereby affect C sequestration, water quality and biodiversity in the future. The team are now in the major phase of data synthesis and model development and are interested in linking with similar studies involving coupled CNP cycles across the atmospheric-terrestrial-freshwater-coastal continuum.

  16. The Multi-Scale Response of Water Quality, Biodiversity and Carbon Sequestration to Coupled Macronutrient Cycling from Source to Sea: TURF2SURF

    NASA Astrophysics Data System (ADS)

    Wade, Andrew; Emmett, Bridget; Jago, Colin; Stutter, Marc; Biggs, Jeremy

    2016-04-01

    Turf2Surf is a large, multi-disciplinary project that aims to test the hypothesis that the spatial and temporal patterns of water quality, C sequestration and biodiversity are better explained through the large-scale coupling of C, N and P cycles than by single cycle, single system approaches. To achieve this, a catchment-scale study of the River Conwy (349 km2) in Wales is being done with emphasis on determining when, where and how coupled macronutrient (C, N, P) cycling occurs in the biogeochemical hot-spots of the soils, the riparian zone, instream and in the river-estuarine transition zone. A major integrated measurement programme is now largely complete. New data are being analysed to understand which soil properties have greatest influence on above and below-ground productivity including plant traits and how microbial processing is controlled by stoichiometry and nutrient priming. Within the stream network, new understanding is being produced on the in-river algal and whole ecosystem (metabolic) response to CNP additions and the factors affecting the fate and cycling of organic matter. In the estuary, initial results indicate a subsurface jet is causing stratification and a velocity anomaly has been observed. Both are important in terms of suspended matter transport and floc break-up. An integrated model is being built to describe the soil-atmosphere-vegetation processes which is linked, firstly, to flow and water quality models that describe the CNP flux transport and transformations from the headwaters to the estuary and, secondly, to biodiversity models. The purpose of the integrated model is to quantify how coupled CNP cycles may respond to environmental change and thereby affect C sequestration, water quality and biodiversity in the future. The team are now in the major phase of data synthesis and model development and are interested in linking with similar studies involving coupled CNP cycles across the atmospheric-terrestrial-freshwater-coastal continuum.

  17. A Method to Test the Effect of Environmental Cues on Mating Behavior in Drosophila melanogaster.

    PubMed

    Gorter, Jenke A; Billeter, Jean-Christophe

    2017-07-17

    An individual's sexual drive is influenced by genotype, experience and environmental conditions. How these factors interact to modulate sexual behaviors remains poorly understood. In Drosophila melanogaster, environmental cues, such as food availability, affect mating activity offering a tractable system to investigate the mechanisms modulating sexual behavior. In D. melanogaster, environmental cues are often sensed via the chemosensory gustatory and olfactory systems. Here, we present a method to test the effect of environmental chemical cues on mating behavior. The assay consists of a small mating arena containing food medium and a mating couple. The mating frequency for each couple is continuously monitored for 24 h. Here we present the applicability of this assay to test environmental compounds from an external source through a pressurized air system as well as manipulation of the environmental components directly in the mating arena. The use of a pressurized air system is especially useful to test the effect of very volatile compounds, while manipulating components directly in the mating arena can be of value to ascertain a compound's presence. This assay can be adapted to answer questions about the influence of genetic and environmental cues on mating behavior and fecundity as well as other male and female reproductive behaviors.

  18. Connected Worlds: Connecting the public with complex environmental systems

    NASA Astrophysics Data System (ADS)

    Uzzo, S. M.; Chen, R. S.; Downs, R. R.

    2016-12-01

    Among the most important concepts in environmental science learning is the structure and dynamics of coupled human and natural systems (CHANS). But the fundamental epistemology for understanding CHANS requires systems thinking, interdisciplinarity, and complexity. Although the Next Generation Science Standards mandate connecting ideas across disciplines and systems, traditional approaches to education do not provide more than superficial understanding of this concept. Informal science learning institutions have a key role in bridging gaps between the reductive nature of classroom learning and contemporary data-driven science. The New York Hall of Science, in partnership with Design I/O and Columbia University's Center for International Earth Science Information Network, has developed an approach to immerse visitors in complex human nature interactions and provide opportunities for those of all ages to elicit and notice environmental consequences of their actions. Connected Worlds is a nearly 1,000 m2 immersive, playful environment in which students learn about complexity and interconnectedness in ecosystems and how ecosystems might respond to human intervention. It engages students through direct interactions with fanciful flora and fauna within and among six biomes: desert, rainforest, grassland, mountain valley, reservoir, and wetlands, which are interconnected through stocks and flows of water. Through gestures and the manipulation of a dynamic water system, Connected Worlds enables students, teachers, and parents to experience how the ecosystems of planet Earth are connected and to observe relationships between the behavior of Earth's inhabitants and our shared world. It is also a cyberlearning platform to study how visitors notice and scaffold their understanding of complex environmental processes and the responses of these processes to human intervention, to help inform the improvement of education practices in complex environmental science.

  19. Environmental Indicators of Metal Pollution and Emission: An Experiment for the Instrumental Analysis Laboratory

    ERIC Educational Resources Information Center

    Bowden, John A.; Nocito, Brian A.; Lowers, Russell H.; Guillette, Louis J., Jr.; Williams, Kathryn R.; Young, Vaneica Y.

    2012-01-01

    This experiment enlightens students on the use of environmental indicators and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and demonstrates the ability of these monitoring tools to measure metal deposition in environmental samples (both as a result of lab-simulated and real events). In this two-part study, the initial…

  20. Karst medium characterization and simulation of groundwater flow in Lijiang Riversed, China

    NASA Astrophysics Data System (ADS)

    Hu, B. X.

    2015-12-01

    It is important to study water and carbon cycle processes for water resource management, pollution prevention and global warming influence on southwest karst region of China. Lijiang river basin is selected as our study region. Interdisciplinary field and laboratory experiments with various technologies are conducted to characterize the karst aquifers in detail. Key processes in the karst water cycle and carbon cycle are determined. Based on the MODFLOW-CFP model, new watershed flow and carbon cycle models are developed coupled subsurface and surface water flow models, flow and chemical/biological models. Our study is focused on the karst springshed in Mao village. The mechanisms coupling carbon cycle and water cycle are explored. Parallel computing technology is used to construct the numerical model for the carbon cycle and water cycle in the small scale watershed, which are calibrated and verified by field observations. The developed coupling model for the small scale watershed is extended to a large scale watershed considering the scale effect of model parameters and proper model structure simplification. The large scale watershed model is used to study water cycle and carbon cycle in Lijiang rivershed, and to calculate the carbon flux and carbon sinks in the Lijiang river basin. The study results provide scientific methods for water resources management and environmental protection in southwest karst region corresponding to global climate change. This study could provide basic theory and simulation method for geological carbon sequestration in China karst region.

  1. Simulation of groundwater flow and evaluation of carbon sink in Lijiang Rivershed, China

    NASA Astrophysics Data System (ADS)

    Hu, Bill X.; Cao, Jianhua; Tong, Juxiu; Gao, Bing

    2016-04-01

    It is important to study water and carbon cycle processes for water resource management, pollution prevention and global warming influence on southwest karst region of China. Lijiang river basin is selected as our study region. Interdisciplinary field and laboratory experiments with various technologies are conducted to characterize the karst aquifers in detail. Key processes in the karst water cycle and carbon cycle are determined. Based on the MODFLOW-CFP model, new watershed flow and carbon cycle models are developed coupled subsurface and surface water flow models, flow and chemical/biological models. Our study is focused on the karst springshed in Mao village. The mechanisms coupling carbon cycle and water cycle are explored. Parallel computing technology is used to construct the numerical model for the carbon cycle and water cycle in the small scale watershed, which are calibrated and verified by field observations. The developed coupling model for the small scale watershed is extended to a large scale watershed considering the scale effect of model parameters and proper model structure simplification. The large scale watershed model is used to study water cycle and carbon cycle in Lijiang rivershed, and to calculate the carbon flux and carbon sinks in the Lijiang river basin. The study results provide scientific methods for water resources management and environmental protection in southwest karst region corresponding to global climate change. This study could provide basic theory and simulation method for geological carbon sequestration in China karst region.

  2. Alternative socio-centric approach for model validation - a way forward for socio-hydrology

    NASA Astrophysics Data System (ADS)

    van Emmerik, Tim; Elshafei, Yasmina; Mahendran, Roobavannan; Kandasamy, Jaya; Pande, Saket; Sivapalan, Murugesu

    2017-04-01

    To better understand and mitigate the impacts of humans on the water cycle, the importance of studying the co-evolution of coupled human-water systems has been recognized. Because of its unique system dynamics, the Murrumbidgee river basin (part of the larger Murray-Darlin basin, Australia) is one of the main study areas in the emerging field of socio-hydrology. In recent years, various historical and modeling studies have contributed to gaining a better understanding of this system's behavior. Kandasamy et al. (2014) performed a historical study on the development of this human-water coupled system. They identified four eras, providing a historical context of the observed "pendulum" swing between first an exclusive focus on agricultural development, followed by increasing environmental awareness, subsequent efforts to mitigate, and finally to restore environmental health. A modeling effort by Van Emmerik et al. (2014) focused on reconstructing hydrological, economical, and societal dynamics and their feedbacks. A measure of changing societal values was included by introducing environmental awareness as an endogenously modeled variable, which resulted in capturing the co-evolution between economic development and environmental health. Later work by Elshafei et al. (2015) modeled and analyzed the two-way feedbacks of land use management and land degradation in two other Australian coupled systems. A composite variable, community sensitivity, was used to measure changing community sentiment, such that the model was capable of isolating the two-way feedbacks in the coupled system. As socio-hydrology adopts a holistic approach, it is often required to introduce (hydrologically) unconventional variables, such as environmental awareness or community sensitivity. It is the subject of ongoing debate how such variables can be validated, as there is no standardized data set available from hydrological or statistical agencies. Recent research (Wei et al. 2017) has provided one such avenue for validation, by using newspaper articles from the last 169 years to derive an index of economic development and environmental sustainability for the complete Murray-Darlin basin. Based on this alternative approach, the similar time periods as Kandasamy et al. (2014) were derived independently. Furthermore, their environmental sustainability index closely follows the parsimoniously modeled environmental awareness from Van Emmerik et al. (2014). Besides a direct validation of previous studies, this independent work provides credibility for the development and use of models such as those developed by Van Emmerik et al. (2014) and Elshafei et al. (2015). With this presentation, we aim to highlight how alternative sources of societal data can be used to independently validate and assess the realism of socio-hydrological models in spite of the fact that at least a significant part of the societal values has to remain endogenous, and only coupled socio-hydrological models of the Van Emmerik et al. (2014) and Elshafei et al. (2014, 2015) are indispensable for any generalization from highly monitored to unmonitored places, underpinned by general theories. References Elshafei, Y., et al. : "A prototype framework for models of socio-hydrology: identification of key feedback loops and parameterisation approach." HESS, 2014. Elshafei, Y., et al. : "A model of the socio-hydrologic dynamics in a semiarid catchment: Isolating feedbacks in the coupled human-hydrology system", WRR, 2015. Kandasamy, J., et al. : "Socio-hydrologic drivers of the pendulum swing between agricultural development and environmental health: a case study from Murrumbidgee River basin, Australia." HESS, 2014. Van Emmerik, T., et al. : "Socio-hydrologic modeling to understand and mediate the competition for water between agriculture development and environmental health: Murrumbidgee River basin, Australia." HESS, 2014. Wei, et al.: "Evolution of the societal value of water resources for economic development versus environmental sustainability in Australia from 1843 to 2011", Global Environmental Change, 2017.

  3. Water-quality monitoring and process understanding in support of environmental policy and management

    USGS Publications Warehouse

    Peters, N.E.

    2008-01-01

    The quantity and quality of freshwater at any point on the landscape reflect the combined effects of many processes operating along hydrological pathways within a drainage basin/watershed/catchment. Primary drivers for the availability of water are landscape changes and patterns, and the processes affecting the timing, magnitude, and intensity of precipitation, including global climate change. The degradation of air, land, and water in one part of a drainage basin can have negative effects on users downstream; the time and space scales of the effects are determined by the residence time along the various hydrological pathways. Hydrology affects transport, deposition, and recycling of inorganic materials and sediment. These components affect biota and associated ecosystem processes, which rely on sustainable flows throughout a drainage basin. Human activities on all spatial scales affect both water quantity and quality, and some human activities can have a disproportionate effect on an entire drainage basin. Aquatic systems have been continuously modified by agriculture, through land-use change, irrigation and navigation, disposal of urban, mining, and industrial wastes, and engineering modifications to the environment. Interdisciplinary integrated basin studies within the last several decades have provided a more comprehensive understanding of the linkages among air, land, and water resources. This understanding, coupled with environmental monitoring, has evolved a more multidisciplinary integrated approach to resource management, particularly within drainage basins.

  4. Coupling Spatiotemporal Community Assembly Processes to Changes in Microbial Metabolism

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Graham, Emily B.; Crump, Alex R.; Resch, Charles T.

    Community assembly processes govern shifts in species abundances in response to environmental change, yet our understanding of assembly remains largely decoupled from ecosystem function. Here, we test hypotheses regarding assembly and function across space and time using hyporheic microbial communities as a model system. We pair sampling of two habitat types through hydrologic fluctuation with null modeling and multivariate statistics. We demonstrate that dual selective pressures assimilate to generate compositional changes at distinct timescales among habitat types, resulting in contrasting associations of Betaproteobacteria and Thaumarchaeota with selection and with seasonal changes in aerobic metabolism. Our results culminate in a conceptualmore » model in which selection from contrasting environments regulates taxon abundance and ecosystem function through time, with increases in function when oscillating selection opposes stable selective pressures. Our model is applicable within both macrobial and microbial ecology and presents an avenue for assimilating community assembly processes into predictions of ecosystem function.« less

  5. Scaling Dissolved Nutrient Removal in River Networks: A Comparative Modeling Investigation

    NASA Astrophysics Data System (ADS)

    Ye, Sheng; Reisinger, Alexander J.; Tank, Jennifer L.; Baker, Michelle A.; Hall, Robert O.; Rosi, Emma J.; Sivapalan, Murugesu

    2017-11-01

    Along the river network, water, sediment, and nutrients are transported, cycled, and altered by coupled hydrological and biogeochemical processes. Our current understanding of the rates and processes controlling the cycling and removal of dissolved inorganic nutrients in river networks is limited due to a lack of empirical measurements in large, (nonwadeable), rivers. The goal of this paper was to develop a coupled hydrological and biogeochemical process model to simulate nutrient uptake at the network scale during summer base flow conditions. The model was parameterized with literature values from headwater streams, and empirical measurements made in 15 rivers with varying hydrological, biological, and topographic characteristics, to simulate nutrient uptake at the network scale. We applied the coupled model to 15 catchments describing patterns in uptake for three different solutes to determine the role of rivers in network-scale nutrient cycling. Model simulation results, constrained by empirical data, suggested that rivers contributed proportionally more to nutrient removal than headwater streams given the fraction of their length represented in a network. In addition, variability of nutrient removal patterns among catchments was varied among solutes, and as expected, was influenced by nutrient concentration and discharge. Net ammonium uptake was not significantly correlated with any environmental descriptor. In contrast, net daily nitrate removal was linked to suspended chlorophyll a (an indicator of primary producers) and land use characteristics. Finally, suspended sediment characteristics and agricultural land use were correlated with net daily removal of soluble reactive phosphorus, likely reflecting abiotic sorption dynamics. Rivers are understudied relative to streams, and our model suggests that rivers can contribute more to network-scale nutrient removal than would be expected based upon their representative fraction of network channel length.

  6. Incense and joss stick making in small household factories, Thailand.

    PubMed

    Siripanich, S; Siriwong, W; Keawrueang, P; Borjan, M; Robson, M

    2014-07-01

    Incense and joss stick are generally used in the world. Most products were made in small household factories. There are many environmental and occupational hazards in these factories. To evaluate the workplace environmental and occupational hazards in small household incense and joss stick factories in Roi-Et, Thailand. Nine small household factories in rural areas of Roi-Et, Thailand, were studied. Dust concentration and small aerosol particles were counted through real time exposure monitoring. The inductively coupled plasma optical emission spectrometry (ICP-OES) was used for quantitative measurement of heavy metal residue in incense products. Several heavy metals were found in dissolved dye and joss sticks. Those included barium, manganese, and lead. Rolling and shaking processes produced the highest concentration of dust and aerosols. Only 3.9% of female workers used personal protection equipment. Dust and chemicals were major threats in small household incense and joss stick factories in Thailand. Increasing awareness towards using personal protection equipment and emphasis on elimination of environmental workplace hazards should be considered to help the workers of this industry.

  7. Ion chromatography-mass spectrometry: a review of recent technologies and applications in forensic and environmental explosives analysis.

    PubMed

    Barron, Leon; Gilchrist, Elizabeth

    2014-01-02

    The development and application of ion chromatography (IC) coupled to mass spectrometry (MS) is discussed herein for the quantitative determination of low-order explosives-related ionic species in environmental and forensic sample types. Issues relating to environmental explosives contamination and the need for more confirmatory IC-MS based applications in forensic science are examined. In particular, the compatibility of a range of IC separation modes with MS detection is summarised along with the analytical challenges that have been overcome to facilitate determinations at the ng-μg L(-1) level. Observed trends in coupling IC to inductively coupled plasma and electrospray ionisation mass spectrometry form a particular focus. This review also includes a discussion of the relative performance of reported IC-MS methods in comparison to orthogonal ion separation-based, spectrometric and spectroscopic approaches to confirmatory detection of low-order explosives. Finally, some promising areas for future research are highlighted and discussed with respect to potential IC-MS applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Architecture and inherent robustness of a bacterial cell-cycle control system.

    PubMed

    Shen, Xiling; Collier, Justine; Dill, David; Shapiro, Lucy; Horowitz, Mark; McAdams, Harley H

    2008-08-12

    A closed-loop control system drives progression of the coupled stalked and swarmer cell cycles of the bacterium Caulobacter crescentus in a near-mechanical step-like fashion. The cell-cycle control has a cyclical genetic circuit composed of four regulatory proteins with tight coupling to processive chromosome replication and cell division subsystems. We report a hybrid simulation of the coupled cell-cycle control system, including asymmetric cell division and responses to external starvation signals, that replicates mRNA and protein concentration patterns and is consistent with observed mutant phenotypes. An asynchronous sequential digital circuit model equivalent to the validated simulation model was created. Formal model-checking analysis of the digital circuit showed that the cell-cycle control is robust to intrinsic stochastic variations in reaction rates and nutrient supply, and that it reliably stops and restarts to accommodate nutrient starvation. Model checking also showed that mechanisms involving methylation-state changes in regulatory promoter regions during DNA replication increase the robustness of the cell-cycle control. The hybrid cell-cycle simulation implementation is inherently extensible and provides a promising approach for development of whole-cell behavioral models that can replicate the observed functionality of the cell and its responses to changing environmental conditions.

  9. Improved Environmental Life Cycle Assessment of Crop Production at the Catchment Scale via a Process-Based Nitrogen Simulation Model.

    PubMed

    Liao, Wenjie; van der Werf, Hayo M G; Salmon-Monviola, Jordy

    2015-09-15

    One of the major challenges in environmental life cycle assessment (LCA) of crop production is the nonlinearity between nitrogen (N) fertilizer inputs and on-site N emissions resulting from complex biogeochemical processes. A few studies have addressed this nonlinearity by combining process-based N simulation models with LCA, but none accounted for nitrate (NO3(-)) flows across fields. In this study, we present a new method, TNT2-LCA, that couples the topography-based simulation of nitrogen transfer and transformation (TNT2) model with LCA, and compare the new method with a current LCA method based on a French life cycle inventory database. Application of the two methods to a case study of crop production in a catchment in France showed that, compared to the current method, TNT2-LCA allows delineation of more appropriate temporal limits when developing data for on-site N emissions associated with specific crops in this catchment. It also improves estimates of NO3(-) emissions by better consideration of agricultural practices, soil-climatic conditions, and spatial interactions of NO3(-) flows across fields, and by providing predicted crop yield. The new method presented in this study provides improved LCA of crop production at the catchment scale.

  10. Nitrogen cycling process rates across urban ecosystems.

    PubMed

    Reisinger, Alexander J; Groffman, Peter M; Rosi-Marshall, Emma J

    2016-09-21

    Nitrogen (N) pollution of freshwater, estuarine, and marine ecosystems is widespread and has numerous environmental and economic impacts. A portion of this excess N comes from urban watersheds comprised of natural and engineered ecosystems which can alter downstream N export. Studies of urban N cycling have focused on either specific ecosystems or on watershed-scale mass balances. Comparisons of specific N transformations across ecosystems are required to contextualize rates from individual studies. Here we reviewed urban N cycling in terrestrial, aquatic, and engineered ecosystems, and compared N processing in these urban ecosystem types to native reference ecosystems. We found that net N mineralization and net nitrification rates were enhanced in urban forests and riparian zones relative to reference ecosystems. Denitrification was highly variable across urban ecosystem types, but no significant differences were found between urban and reference denitrification rates. When focusing on urban streams, ammonium uptake was more rapid than nitrate uptake in urban streams. Additionally, reduction of stormwater runoff coupled with potential decreases in N concentration suggests that green infrastructure may reduce downstream N export. Despite multiple environmental stressors in urban environments, ecosystems within urban watersheds can process and transform N at rates similar to or higher than reference ecosystems. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Understanding coupling between natural and human systems to ensure disease resilient societies

    NASA Astrophysics Data System (ADS)

    Jutla, A.; Nguyen, T. H.; Colwell, R. R.; Akanda, A. S.

    2016-12-01

    Human well-being is one of the key long-term indicators of a sustainable environment. John Snow, a prominent 19th century physician, provided insights on the role of drinking contaminated water and cholera outbreak(s). Extrapolation of Snow's discovery on locating source of cholera bacteria (in local wells) lead to the tenets of traditional doctrines of environmental sustainability of water where source capacities (such as physical condition of water) are directly linked to sink capacities (e.g., bacterial growth in water) of a system, a balance that must be maintained to sustain human life supporting mechanisms. With a changing climate, stress on availability of safe drinking water is likely to increase, particularly where population vulnerability intersects with hydroclimatic extremes. This raises a critical question on how environmental sustainability of water will affect human societies. A dynamic equilibrium exists between large scale geophysical (e.g., sea surface temperature-SST; precipitation, evaporative fluxes) and local scale water-ecological processes (salinity, plankton, organic matter) in water resources (ponds, rivers, lakes). The ecological processes aid in growth and proliferation of water based pathogens (such as cholera, Rotavirus, Shigella and other vibrios). Societal determinants, such as access to safe drinking water and sanitation facilities, defines interaction of human population with water. The feedback loop, between geophysical and water-ecological processes is fundamental to ensure a sustainable environment for human well-being. However, the feedback loops are often misconstrued resulting in massive loss of human life, and further leading to outbreak of diseases at various spatial and temporal scales across region(s). Using historical data on Cholera and Zika virus as examples, we will demonstrate the intricacies involved in understanding coupled human-natural system. The two infections result from a very different asymmetric hydroclimatic regimens, and the feedback loops determine interaction of humans with the pathogens.

  12. Modeling the Impact of Deformation on Unstable Miscible Displacements in Porous Media

    NASA Astrophysics Data System (ADS)

    Santillán, D.; Cueto-Felgueroso, L.

    2014-12-01

    Coupled flow and geomechanics is a critical research challenge in engineering and the geosciences. The simultaneous flow of two or more fluids with different densities or viscosities through deformable media is ubiquitous in environmental, industrial, and biological processes, including the removal of non-aqueous phase liquids from underground water bodies, the geological storage of CO2, and current challenges in energy technologies, such as enhanced geothermal systems, unconventional hydrocarbon resources or enhanced oil recovery techniques. Using numerical simulation, we study the interplay between viscous-driven flow instabilities (viscous fingering) and rock mechanics, and elucidate the structure of the displacement patterns as a function of viscosity contrast, injection rate and rock mechanical properties. Finally, we discuss the role of medium deformation on transport and mixing processes in porous media.

  13. RNA Polymerase II Elongation Control

    PubMed Central

    Zhou, Qiang; Li, Tiandao; Price, David H.

    2014-01-01

    Regulation of the elongation phase of transcription by RNA Polymerase II (Pol II) is utilized extensively to generate the pattern of mRNAs needed to specify cell types and to respond to environmental changes. After Pol II initiates, negative elongation factors cause it to pause in a promoter proximal position. These polymerases are poised to respond to the positive transcription elongation factor, P-TEFb, and then enter productive elongation only under the appropriate set of signals to generate full length properly processed mRNAs. Recent global analyses of Pol II and elongation factors, mechanisms that regulate P-TEFb involving the 7SK snRNP, factors that control both the negative and positive elongation properties of Pol II and the mRNA processing events that are coupled with elongation are discussed. PMID:22404626

  14. Recent approaches for the direct use of elemental sulfur in the synthesis and processing of advanced materials.

    PubMed

    Lim, Jeewoo; Pyun, Jeffrey; Char, Kookheon

    2015-03-09

    Elemental sulfur is an abundant and inexpensive material obtained as a by-product of natural-gas and petroleum refining operations. Recently, the need for the development of new energy-storage systems brought into light the potential of sulfur as a high-capacity cathode material in secondary batteries. Sulfur-containing materials were also shown to have useful IR optical properties. These developments coupled with growing environmental concerns related to the global production of excess elemental sulfur have led to a keen interest in its utilization as a feedstock in materials applications. This Minireview focuses on the recent developments on physical and chemical methods for directly processing elemental sulfur to produce functional composites and polymers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Biomedical data integration - capturing similarities while preserving disparities.

    PubMed

    Bianchi, Stefano; Burla, Anna; Conti, Costanza; Farkash, Ariel; Kent, Carmel; Maman, Yonatan; Shabo, Amnon

    2009-01-01

    One of the challenges of healthcare data processing, analysis and warehousing is the integration of data gathered from disparate and diverse data sources. Promoting the adoption of worldwide accepted information standards along with common terminologies and the use of technologies derived from semantic web representation, is a suitable path to achieve that. To that end, the HL7 V3 Reference Information Model (RIM) [1] has been used as the underlying information model coupled with the Web Ontology Language (OWL) [2] as the semantic data integration technology. In this paper we depict a biomedical data integration process and demonstrate how it was used for integrating various data sources, containing clinical, environmental and genomic data, within Hypergenes, a European Commission funded project exploring the Essential Hypertension [3] disease model.

  16. Impact of Climate Change on Soil and Groundwater Chemistry Subject to Process Waste Land Application

    NASA Astrophysics Data System (ADS)

    McNab, W. W.

    2013-12-01

    Nonhazardous aqueous process waste streams from food and beverage industry operations are often discharged via managed land application in a manner designed to minimize impacts to underlying groundwater. Process waste streams are typically characterized by elevated concentrations of solutes such as ammonium, organic nitrogen, potassium, sodium, and organic acids. Land application involves the mixing of process waste streams with irrigation water which is subsequently applied to crops. The combination of evapotranspiration and crop salt uptake reduces the downward mass fluxes of percolation water and salts. By carefully managing application schedules in the context of annual climatological cycles, growing seasons, and process requirements, potential adverse environmental impacts to groundwater can be mitigated. However, climate change poses challenges to future process waste land application efforts because the key factors that determine loading rates - temperature, evapotranspiration, seasonal changes in the quality and quantity of applied water, and various crop factors - are all likely to deviate from current averages. To assess the potential impact of future climate change on the practice of land application, coupled process modeling entailing transient unsaturated fluid flow, evapotranspiration, crop salt uptake, and multispecies reactive chemical transport was used to predict changes in salt loading if current practices are maintained in a warmer, drier setting. As a first step, a coupled process model (Hydrus-1D, combined with PHREEQC) was calibrated to existing data sets which summarize land application loading rates, soil water chemistry, and crop salt uptake for land disposal of process wastes from a food industry facility in the northern San Joaquin Valley of California. Model results quantify, for example, the impacts of evapotranspiration on both fluid flow and soil water chemistry at shallow depths, with secondary effects including carbonate mineral precipitation and ion exchange. The calibrated model was then re-run assuming different evapotranspiration and crop growth regimes, and different seasonally-adjusted applied water compositions, to elucidate possible impacts to salt loading reactive chemistry. The results of the predictive modeling indicate the extent to which salts could be redistributed within the soil column as a consequence of climate change. The degree to which these findings are applicable to process waste land application operations at other sites was explored by varying the soil unsaturated flow parameters as a model sensitivity assessment. Taken together, the model results help to quantify operational changes to land application that may be necessary to avoid future adverse environmental impacts to soil and groundwater.

  17. A New Perspective on the Foraging Ecology of Apex Predators in the California Current: Results from a Fully Coupled Ecosystem Model

    NASA Astrophysics Data System (ADS)

    Fiechter, J.; Huckstadt, L. A.; Rose, K.; Costa, D. P.; Curchitser, E. N.; Hedstrom, K.; Edwards, C. A.; Moore, A. M.

    2016-02-01

    Results from a fully coupled end-to-end ecosystem model for the California Current Large Marine Ecosystem are used to describe the impact of environmental variability on the foraging ecology of its most abundant apex predator, California sea lions (Zalophus californianus). The ecosystem model consists of a biogeochemical submodel embedded in a regional ocean circulation submodel, and both coupled with a multi-species individual-based submodel for forage fish (sardine and anchovy) and California sea lions. For sea lions, bioenergetics and behavioral attributes are specified using available TOPP (Tagging Of Pacific Predators) data on their foraging patterns and diet in the California Current. Sardine and anchovy are explicitly included in the model as they represent important prey sources for California sea lions and exhibit significant interannual and decadal variability in population abundances. Output from a 20-year run (1989-2008) of the model demonstrates how different physical and biological processes control habitat utilization and foraging success of California sea lions on interannual time scales. A principal component analysis of sea lion foraging patterns indicates that the first mode of variability is alongshore and tied to sardine availability, while the second mode is cross-shore and associated with coastal upwelling intensity (a behavior consistent with male sea lion tracking data collected in 2004 vs. 2005). The results also illustrate how variability in environmental conditions and forage fish distribution affects sea lions feeding success. While specifically focusing on the foraging ecology of sea lions, our modeling framework has the ability to provide new and unique perspectives on trophic interactions in the California Current, or other regions where similar end-to-end ecosystem models may be implemented.

  18. Filling two needs with one deed: Potentials to simultaneously improve phosphorus and nitrogen management in Austria as an example for coupled resource management systems.

    PubMed

    Tanzer, Julia; Zoboli, Ottavia; Zessner, Matthias; Rechberger, Helmut

    2018-06-04

    The tremendous increase in resource consumption over the past century and the environmental challenges it entails has spurred discussions for a shift from a linear to a circular resource use. However, to date most resource studies are restricted to one material or a single sector or process. In this work, a coupled material flow analysis taking the national phosphorus (P) and nitrogen (N) system of Austria as an example for two closely connected resource systems is conducted. Effects of different measures aimed at reducing P and/or N-demand, increasing recycling or reducing emissions to air and water are compared to a reference state (representing the actual situation in 2015). Changes in the mineral fertilizer demand of the system, P and N losses in the waste sector, water emissions of P and N, P soil accumulation and atmospheric N emissions are analyzed. Overall positive feedbacks between measures and between different goals of one measure always outweigh negative ones, which is why the highest efficiency gains (57±4%) can be achieved by a combination of all the 16 measures studied. Potentials for the reduction of mineral fertilizer demand are larger than for emission reduction though, confirming the past priority of environmental protection over resource protection. Although coupling significantly raises model complexity it can be shown that material flows of more than one substance can be simultaneously analyzed in a rather complex system. This may reveal interrelations, co-benefits and trade-offs between different resources that might have been omitted in a mono-substance analysis and thus improve judgment of sustainability and viability of different management strategies. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Developing a Salivary Antibody Multiplex Immunoassay to ...

    EPA Pesticide Factsheets

    The etiology and impacts of human exposure to environmental pathogens are of major concern worldwide and, thus, the ability to assess exposure and infections using cost effective, high-throughput approaches would be indispensable. The principal objective of this work is to develop an immunoassay capable of measuring the presence of antibodies in human saliva to multiple pathogens simultaneously. Saliva is particularly attractive in this application because it is noninvasive, cheaper and easier to collect than serum. Antigens from environmental pathogens were coupled to carboxylated microspheres (beads) and used to measure antibodies in very small volumes of human saliva samples using the Luminex xMAP solution-phase assay. Beads were coupled to antigens from Campylobacter jejuni, Helicobacter pylori, Toxoplasma gondii, noroviruses (G I.1 and G II.4) and hepatitis A virus. To ensure that the antigens were sufficiently coupled to the beads, coupling was confirmed using species-specific, animal-derived primary detection antibodies, followed by incubation with biotinylated anti-species secondary detection antibodies and streptavidin-R-phycoerythrin reporter (SAPE). As a control to measure non-specific binding, one bead set was treated identically to the others except it was not coupled to any antigen. The antigen coupled and control beads were then incubated with prospectively-collected human saliva samples, analyzed on a Luminex 100 platform, and the presence

  20. Major weapon system environmental life-cycle cost estimating for Conservation, Cleanup, Compliance and Pollution Prevention (C3P2)

    NASA Technical Reports Server (NTRS)

    Hammond, Wesley; Thurston, Marland; Hood, Christopher

    1995-01-01

    The Titan 4 Space Launch Vehicle Program is one of many major weapon system programs that have modified acquisition plans and operational procedures to meet new, stringent environmental rules and regulations. The Environmental Protection Agency (EPA) and the Department of Defense (DOD) mandate to reduce the use of ozone depleting chemicals (ODC's) is just one of the regulatory changes that has affected the program. In the last few years, public environmental awareness, coupled with stricter environmental regulations, has created the need for DOD to produce environmental life-cycle cost estimates (ELCCE) for every major weapon system acquisition program. The environmental impact of the weapon system must be assessed and budgeted, considering all costs, from cradle to grave. The Office of the Secretary of Defense (OSD) has proposed that organizations consider Conservation, Cleanup, Compliance and Pollution Prevention (C(sup 3)P(sup 2)) issues associated with each acquisition program to assess life-cycle impacts and costs. The Air Force selected the Titan 4 system as the pilot program for estimating life-cycle environmental costs. The estimating task required participants to develop an ELCCE methodology, collect data to test the methodology and produce a credible cost estimate within the DOD C(sup 3)P(sup 2) definition. The estimating methodology included using the Program Office weapon system description and work breakdown structure together with operational site and manufacturing plant visits to identify environmental cost drivers. The results of the Titan IV ELCCE process are discussed and expanded to demonstrate how they can be applied to satisfy any life-cycle environmental cost estimating requirement.

  1. Microbiota Dynamics Associated with Environmental Conditions and Potential Roles of Cellulolytic Communities in Traditional Chinese Cereal Starter Solid-State Fermentation

    PubMed Central

    Li, Pan; Liang, Hebin; Lin, Wei-Tie; Feng, Feng

    2015-01-01

    Traditional Chinese solid-state fermented cereal starters contain highly complex microbial communities and enzymes. Very little is known, however, about the microbial dynamics related to environmental conditions, and cellulolytic communities have never been proposed to exist during cereal starter fermentation. In this study, we performed Illumina MiSeq sequencing combined with PCR-denaturing gradient gel electrophoresis to investigate microbiota, coupled with clone library construction to trace cellulolytic communities in both fermentation stages. A succession of microbial assemblages was observed during the fermentation of starters. Lactobacillales and Saccharomycetales dominated the initial stages, with a continuous decline in relative abundance. However, thermotolerant and drought-resistant Bacillales, Eurotiales, and Mucorales were considerably accelerated during the heating stages, and these organisms dominated until the end of fermentation. Enterobacteriales were consistently ubiquitous throughout the process. For the cellulolytic communities, only the genera Sanguibacter, Beutenbergia, Agrobacterium, and Erwinia dominated the initial fermentation stages. In contrast, stages at high incubation temperature induced the appearance and dominance of Bacillus, Aspergillus, and Mucor. The enzymatic dynamics of amylase and glucoamylase also showed a similar trend, with the activities clearly increased in the first 7 days and subsequently decreased until the end of fermentation. Furthermore, β-glucosidase activity continuously and significantly increased during the fermentation process. Evidently, cellulolytic potential can adapt to environmental conditions by changes in the community structure during the fermentation of starters. PMID:26002897

  2. Towards improved capability and confidence in coupled atmospheric and wildland fire modeling

    NASA Astrophysics Data System (ADS)

    Sauer, Jeremy A.

    This dissertation work is aimed at improving the capability and confidence in a modernized and improved version of Los Alamos National Laboratory's coupled atmospheric and wild- land fire dynamics model, Higrad-Firetec. Higrad is the hydrodynamics component of this large eddy simulation model that solves the three dimensional, fully compressible Navier-Stokes equations, incorporating a dynamic eddy viscosity formulation through a two-scale turbulence closure scheme. Firetec is the vegetation, drag forcing, and combustion physics portion that is integrated with Higrad. The modern version of Higrad-Firetec incorporates multiple numerical methodologies and high performance computing aspects which combine to yield a unique tool capable of augmenting theoretical and observational investigations in order to better understand the multi-scale, multi-phase, and multi-physics, phenomena involved in coupled atmospheric and environmental dynamics. More specifically, the current work includes extended functionality and validation efforts targeting component processes in coupled atmospheric and wildland fire scenarios. Since observational data of sufficient quality and resolution to validate the fully coupled atmosphere-wildfire scenario simply does not exist, we instead seek to validate components of the full prohibitively convoluted process. This manuscript provides first, an introduction and background into the application space of Higrad-Firetec. Second we document the model formulation, solution procedure, and a simple scalar transport verification exercise. Third, we perform a validate model results against observational data for time averaged flow field metrics in and above four idealized forest canopies. Fourth, we carry out a validation effort for the non-buoyant jet in a crossflow scenario (to which an analogy can be made for atmosphere-wildfire interactions) comparing model results to laboratory data of both steady-in-time and unsteady-in-time metrics. Finally, an extension of model multi-phase physics is implemented, allowing for the representation of multiple collocated fuels as separately evolving constituents leading to differences resulting rate of spread and total burned area. In combination these efforts demonstrate improved capability, increased validation of component functionality, and unique applicability the Higrad-Firetec modeling framework. As a result this work provides a substantially more robust foundation for future new, more widely acceptable investigations into the complexities of coupled atmospheric and wildland fire behavior.

  3. Health, trust, or "just understood": explicit and implicit condom decision-making processes among black, white, and interracial same-sex male couples.

    PubMed

    Campbell, Chadwick K; Gómez, Anu Manchikanti; Dworkin, Shari; Wilson, Patrick A; Grisham, Kirk K; McReynolds, Jaih; Vielehr, Peter; Hoff, Colleen

    2014-05-01

    Among gay and bisexual men, primary partners are a leading source of HIV infection. Trust, intimacy, and advancements in HIV treatment may impact same-sex male (SSM) couples' decisions to engage in unprotected anal intercourse (UAI). This qualitative study explored how Black, White and interracial couples discussed, and made decisions regarding condoms. Qualitative interviews were conducted with 48 SSM couples in the New York and San Francisco metropolitan areas. Stratified purposive sampling was used to include Black (n = 16), White (n = 17), and interracial (Black-White) (n = 15) couples. Twenty-six couples were concordant HIV-negative and 22 were HIV-discordant. Interviews were recorded, transcribed, coded, and analyzed using a grounded theory approach. Some couples described explicit processes, which involved active discussion, while others described implicit processes, where condom-use decisions occurred without any explicit discussion. These processes also differed by race and HIV status. Black couples tended to report condom-use as "just understood." White, HIV-discordant couples decided not to use condoms, with some identifying the HIV-positive partner's suppressed viral load and high CD4 count as deciding factors. After an unplanned episode of UAI, White, HIV-negative couples tended to discontinue condom use while Black HIV-negative couples decided to revert to using condoms. HIV prevention efforts focused on same-sex, male couples must consider the explicit/implicit nature of condom decision-making processes. Understanding differences in these processes and considering relationship dynamics, across race and HIV status, can promote the development of innovative couple-level, HIV prevention interventions.

  4. Some trends and proposals for the inclusion of sustainability in the design of manufacturing process

    NASA Astrophysics Data System (ADS)

    Fradinho, J.; Nedelcu, D.; Gabriel-Santos, A.; Gonçalves-Coelho, A.; Mourão, A.

    2015-11-01

    Production processes are designed to meet requirements of three different natures, quality, cost and time. Environmental concerns have expanded the field of conceptual design through the introduction of sustainability requirements that are driven by the growing societal thoughtfulness about environmental issues. One could say that the major concern has been the definition of metrics or indices for sustainability. However, those metrics usually have some lack of consistency. More than ever, there is a need for an all-inclusive view at any level of decision-making, from the establishing of the design requirements to the implementation of the solutions. According to the Axiomatic Design Theory, sustainable designs are usually coupled designs that should be avoided. This raises a concern related to the very nature of sustainability: the cross effects between the actions that should be considered in the attempt to decouple the design solutions. In terms of production, one should clarify the characterization of the sustainability of production systems. The objectives of this paper are: i) to analyse some trends for approaching the sustainability of the production processes; ii) to define sustainability in terms of requirements for the design of the production processes; iii) to make some proposals based on the Axiomatic Design Theory, in order to establish the principles with which the guidelines for designing production processes must comply; iv) to discuss how to introduce this matter in teaching both manufacturing technology and design of production systems.

  5. High performance of a cobalt–nitrogen complex for the reduction and reductive coupling of nitro compounds into amines and their derivatives

    PubMed Central

    Zhou, Peng; Jiang, Liang; Wang, Fan; Deng, Kejian; Lv, Kangle; Zhang, Zehui

    2017-01-01

    Replacement of precious noble metal catalysts with low-cost, non-noble heterogeneous catalysts for chemoselective reduction and reductive coupling of nitro compounds holds tremendous promise for the clean synthesis of nitrogen-containing chemicals. We report a robust cobalt–nitrogen/carbon (Co–Nx/C-800-AT) catalyst for the reduction and reductive coupling of nitro compounds into amines and their derivates. The Co–Nx/C-800-AT catalyst was prepared by the pyrolysis of cobalt phthalocyanine–silica colloid composites and the subsequent removal of silica template and cobalt nanoparticles. The Co–Nx/C-800-AT catalyst showed extremely high activity, chemoselectivity, and stability toward the reduction of nitro compounds with H2, affording full conversion and >97% selectivity in water after 1.5 hours at 110°C and under a H2 pressure of 3.5 bar for all cases. The hydrogenation of nitrobenzene over the Co–Nx/C-800-AT catalyst can even be smoothly performed under very mild conditions (40°C and a H2 pressure of 1 bar) with an aniline yield of 98.7%. Moreover, the Co–Nx/C-800-AT catalyst has high activity toward the transfer hydrogenation of nitrobenzene into aniline and the reductive coupling of nitrobenzene into other derivates with high yields. These processes were carried out in an environmentally friendly manner without base and ligands. PMID:28232954

  6. Interventions and Interactions: Understanding Coupled Human-Water Dynamics for Improved Water Resources Management in the Himalayas

    NASA Astrophysics Data System (ADS)

    Crootof, A.

    2017-12-01

    Understanding coupled human-water dynamics offers valuable insights to address fundamental water resources challenges posed by environmental change. With hydropower reshaping human-water interactions in mountain river basins, there is a need for a socio-hydrology framework—which examines two-way feedback loops between human and water systems—to more effectively manage water resources. This paper explores the cross-scalar interactions and feedback loops between human and water systems in river basins affected by run-of-the-river hydropower and highlights the utility of a socio-hydrology perspectives to enhance water management in the face of environmental change. In the Himalayas, the rapid expansion of run-of-the-river hydropower—which diverts streamflow for energy generation—is reconfiguring the availability, location, and timing of water resources. This technological intervention in the river basin not only alters hydrologic dyanmics but also shapes social outcomes. Using hydropower development in the highlands of Uttarakhand, India as a case study, I first illustrate how run-of-the-river projects transform human-water dynamics by reshaping the social and physical landscape of a river basin. Second, I emphasize how examining cross-scalar feedbacks among structural dynamics, social outcomes, and values and norms in this coupled human-water system can inform water management. Third, I present hydrological and social literature, raised separately, to indicate collaborative research needs and knowledge gaps for coupled human-water systems affected by run-of-the-river hydropower. The results underscore the need to understand coupled human-water dynamics to improve water resources management in the face of environmental change.

  7. Novel model coupling approach for resilience analysis of coastal plant communities.

    PubMed

    Schibalski, Anett; Körner, Katrin; Maier, Martin; Jeltsch, Florian; Schröder, Boris

    2018-06-04

    Resilience is a major research focus covering a wide range of topics from biodiversity conservation to ecosystem (service) management. Model simulations can assess the resilience of, e.g., plant species, measured as the return time to conditions prior to a disturbance. This requires process-based models (PBM) that implement relevant processes like regeneration and reproduction and thus successfully reproduce transient dynamics after disturbances. Such models are often complex and thus limited to either short-term or small-scale applications, whereas many research questions require species predictions across larger spatial and temporal scales. We suggest a framework to couple a PBM and a statistical species distribution model (SDM), which transfers the results of a resilience analysis by the PBM to SDM predictions. The resulting hybrid model combines the advantages of both approaches: the convenient applicability of SDMs and the relevant process detail of PBMs in abrupt environmental change situations. First, we simulate dynamic responses of species communities to a disturbance event with a PBM. We aggregate the response behavior in two resilience metrics: return time and amplitude of the response peak. These metrics are then used to complement long-term SDM projections with dynamic short-term responses to disturbance. To illustrate our framework, we investigate the effect of abrupt short-term groundwater level and salinity changes on coastal vegetation at the German Baltic Sea. We found two example species to be largely resilient, and, consequently, modifications of SDM predictions consisted mostly of smoothing out peaks in the occurrence probability that were not confirmed by the PBM. Discrepancies between SDM- and PBM-predicted species responses were caused by community dynamics simulated in the PBM and absent from the SDM. Although demonstrated with boosted regression trees (SDM) and an existing individual-based model, IBC-grass (PBM), our flexible framework can easily be applied to other PBM and SDM types, as well as other definitions of short-term disturbances or long-term trends of environmental change. Thus, our framework allows accounting for biological feedbacks in the response to short- and long-term environmental changes as a major advancement in predictive vegetation modeling. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. Tools for Virtual Collaboration Designed for High Resolution Hydrologic Research with Continental-Scale Data Support

    NASA Astrophysics Data System (ADS)

    Duffy, Christopher; Leonard, Lorne; Shi, Yuning; Bhatt, Gopal; Hanson, Paul; Gil, Yolanda; Yu, Xuan

    2015-04-01

    Using a series of recent examples and papers we explore some progress and potential for virtual (cyber-) collaboration inspired by access to high resolution, harmonized public-sector data at continental scales [1]. The first example describes 7 meso-scale catchments in Pennsylvania, USA where the watershed is forced by climate reanalysis and IPCC future climate scenarios (Intergovernmental Panel on Climate Change). We show how existing public-sector data and community models are currently able to resolve fine-scale eco-hydrologic processes regarding wetland response to climate change [2]. The results reveal that regional climate change is only part of the story, with large variations in flood and drought response associated with differences in terrain, physiography, landuse and/or hydrogeology. The importance of community-driven virtual testbeds are demonstrated in the context of Critical Zone Observatories, where earth scientists from around the world are organizing hydro-geophysical data and model results to explore new processes that couple hydrologic models with land-atmosphere interaction, biogeochemical weathering, carbon-nitrogen cycle, landscape evolution and ecosystem services [3][4]. Critical Zone cyber-research demonstrates how data-driven model development requires a flexible computational structure where process modules are relatively easy to incorporate and where new data structures can be implemented [5]. From the perspective of "Big-Data" the paper points out that extrapolating results from virtual observatories to catchments at continental scales, will require centralized or cloud-based cyberinfrastructure as a necessary condition for effectively sharing petabytes of data and model results [6]. Finally we outline how innovative cyber-science is supporting earth-science learning, sharing and exploration through the use of on-line tools where hydrologists and limnologists are sharing data and models for simulating the coupled impacts of catchment hydrology on lake eco-hydrology (NSF-INSPIRE, IIS1344272). The research attempts to use a virtual environment (www.organicdatascience.org) to break down disciplinary barriers and support emergent communities of science. [1] Source: Leonard and Duffy, 2013, Environmental Modelling & Software; [2] Source: Yu et al, 2014, Computers in Geoscience; [3] Source: Duffy et al, 2014, Procedia Earth and Planetary Science; [4] Source: Shi et al, Journal of Hydrometeorology, 2014; [5] Source: Bhatt et al, 2014, Environmental Modelling & Software ; [6] Leonard and Duffy, 2014, Environmental Modelling and Software.

  9. Gas chromatography--inductively coupled plasma--time-of-flight mass spectrometry for the speciation analysis of organolead compounds in environmental water samples.

    PubMed

    Heisterkamp, M; Adams, F C

    2001-07-01

    The application of inductively coupled plasma--time-of-flight mass spectrometry for the speciation analysis of organolead compounds in environmental waters is described. Construction of the transfer line was achieved by means of a relatively simple and rapid coupling procedure. Derivatization of the ionic lead species was achieved by in-situ propylation with sodium tetrapropylborate; simultaneous extraction of the derivatized compounds in hexane was followed by separation and detection by capillary gas chromatography hyphenated to inductively coupled plasma-time-of-flight mass spectrometry. Detection limits for the different organolead species ranged from 10 to 15 fg (as Pb), corresponding to procedural detection limits between 50 and 75 ng L(-1), on the basis of a 50 mL snow sample, extraction with 200 microL hexane, and subsequent injection of 1 microL of the organic extract on to the column. The accuracy of the system was confirmed by additional analysis of the water samples by capillary gas chromatography coupled with microwave-induced plasma-atomic-emission spectrometry and the analysis of a standard reference material CRM 605 (road dust) with a certified content of trimethyllead.

  10. Ecohydrology of a Tropical Landscape: Hydrological Regimes and Implications for Water Resources and Ecological Dynamics in the Talgua Watershed, Honduras

    NASA Astrophysics Data System (ADS)

    Reyes, W. M.; Jass, T. L.; Emanuel, R. E.

    2016-12-01

    The tropics play a central role in regulating Earth's environmental systems, not only cycling more water than any other region in the world but also influencing global biogeochemical and energy balances. Increasing and widespread deforestation, climate change, and other disturbances are rapidly altering Earth system processes in the tropics, yet our understanding of these processes and their implications is limited for certain locations. Honduras, located within the Mesoamerican region, is one such location. A combination of rapid land use change (including deforestation at 3% y-1), hurricanes, droughts, poor access to drinking water, and poverty place Honduras among the most environmentally vulnerable countries in the world. However, these factors also create an ideal scenario for understanding complex human-environment interactions and their effects on tropical eco-hydrological systems. To this end, we collected and analyzed hydrological and meteorological data from the upper Talgua River, a forested, montane catchment in the headwaters of Honduras' Patuca River, during 2015 and 2016. We characterized the water balance and basic water quality relationships for the Talgua River, an important accomplishment for such a data-sparse region. We place our results in the context of coupled human-water dynamics in this region of Mesoamerica and discuss implications for water resources and other environmental services. Our analyses, embedded research infrastructure, and long-term partnerships with local institutions help provide valuable insights that narrow the existing knowledge gap in tropical ecohydrology and related socio-environmental dynamics. Our work also helps local communities and governments plan and make well-informed decisions about water and related resources.

  11. Use of mass spectrometry coupled with a solids insertion probe to prescreen soil samples for environmental samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Check, C.E.; Bach, S.B.H.

    1995-12-31

    The contamination of air, water, and soils by a myriad of sources generates a large sample Currently, sample volume for hazardous constituent analyses is approximately half a million samples per year. The total analytical costs associated with this are astronomical. The analysis of these samples is vital in terms of assessing the types of contamination present and to what degree a site has been contaminated. The results of these analyses are very important for making an informed, knowledgeable decision as to the need for remediation and what type of remediation processes should be initiated based on site suitability vs non-actionmore » for the various sample sites. With an ever growing environmental consciousness in today`s society, the assessment and subsequent remediation of a site needs to be accomplished promptly despite the time constraints traditional methods place on such actions. In order to facilitate a rapid assessment, it is desirable to utilize instrumentation and equipment which afford the most information about a site allowing for optimization in environmental assessment while maintaining a realistic time schedule for the resulting remediation process. Because there are various types of environmental samples that can be taken at a site, different combinations of instrumentation and methods are required for assessing the level and type of contamination present whether it is in air, water, or soils. This study is limited to analyzing soil-like media that would normally fall under EPA Method 8270 which is used to analyze solid waste matrices, soils, and groundwater for semi-volatile organic compounds.« less

  12. Environmental ethics: an overview, assessing the place of bioscientists in society, supplemented with selected Australian perspectives.

    PubMed

    Buckeridge, John

    2014-01-01

    Ethics deals with moral behavior in a professional context; ideally, it leads to a set of governing principles through which the appropriateness of any activity may be determined or assessed. Environmental ethics specifically deals with how humans interact with the biosphere. It is clear, however, that, as a species, we are failing in our duty of environmental stewardship. The encroachment of human activity into the natural environment is inexorable, and almost always deleterious. Any response to mitigate loss of taxa or ecosystems will have economic implications, and these are often considerable. In finding effective solutions, a process soon becomes political. In light of this we must reflect upon the leadership role that biologists have, especially our impact on policy development that pertains to natural resource management. Although our track record is no worse than any other professional group, biologists by way of training usually have a greater understanding of natural processes and must be prepared to articulate these publically. We have an ethical mandate to question decisions, policies and legislation that impact negatively upon biological systems: a mandate guided through logic, grounded in empirical science, and hopefully coupled with a deep understanding of the true value of both the living world and the physical world which sustains it. This paper uses Australian examples to demonstrate the frequent clashes between economics and biology, in anticipation that we should strive to achieve the underlying principles of sustainability, environmental stewardship and resource management in both daily decision-making and in long-term planning. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

  13. Nitrous Oxide Abatement Coupled with Biopolymer Production As a Model GHG Biorefinery for Cost-Effective Climate Change Mitigation.

    PubMed

    Frutos, Osvaldo D; Cortes, Irene; Cantera, Sara; Arnaiz, Esther; Lebrero, Raquel; Muñoz, Raúl

    2017-06-06

    N 2 O represents ∼6% of the global greenhouse gas emission inventory and the most important O 3 -depleting substance emitted in this 21st century. Despite its environmental relevance, little attention has been given to cost-effective and environmentally friendly N 2 O abatement methods. Here we examined, the potential of a bubble column (BCR) and an internal loop airlift (ALR) bioreactors of 2.3 L for the abatement of N 2 O from a nitric acid plant emission. The process was based on the biological reduction of N 2 O by Paracoccus denitrificans using methanol as a carbon/electron source. Two nitrogen limiting strategies were also tested for the coproduction of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) coupled with N 2 O reduction. High N 2 O removal efficiencies (REs) (≈87%) together with a low PHBV cell accumulation were observed in both bioreactors in excess of nitrogen. However, PHBV contents of 38-64% were recorded under N limiting conditions along with N 2 O-REs of ≈57% and ≈84% in the ALR and BCR, respectively. Fluorescence in situ hybridization analyses showed that P. denitrificans was dominant (>50%) after 6 months of experimentation. The successful abatement of N 2 O concomitant with PHBV accumulation confirmed the potential of integrating biorefinery concepts into biological gas treatment for a cost-effective GHG mitigation.

  14. Strain-specific differences in pili formation and the interaction of Corynebacterium diphtheriae with host cells

    PubMed Central

    2010-01-01

    Background Corynebacterium diphtheriae, the causative agent of diphtheria, is well-investigated in respect to toxin production, while little is known about C. diphtheriae factors crucial for colonization of the host. In this study, we investigated strain-specific differences in adhesion, invasion and intracellular survival and analyzed formation of pili in different isolates. Results Adhesion of different C. diphtheriae strains to epithelial cells and invasion of these cells are not strictly coupled processes. Using ultrastructure analyses by atomic force microscopy, significant differences in macromolecular surface structures were found between the investigated C. diphtheriae strains in respect to number and length of pili. Interestingly, adhesion and pili formation are not coupled processes and also no correlation between invasion and pili formation was found. Using RNA hybridization and Western blotting experiments, strain-specific pili expression patterns were observed. None of the studied C. diphtheriae strains had a dramatic detrimental effect on host cell viability as indicated by measurements of transepithelial resistance of Detroit 562 cell monolayers and fluorescence microscopy, leading to the assumption that C. diphtheriae strains might use epithelial cells as an environmental niche supplying protection against antibodies and macrophages. Conclusions The results obtained suggest that it is necessary to investigate various isolates on a molecular level to understand and to predict the colonization process of different C. diphtheriae strains. PMID:20942914

  15. Perspective: Aerosol microphysics: From molecules to the chemical physics of aerosols

    NASA Astrophysics Data System (ADS)

    Bzdek, Bryan R.; Reid, Jonathan P.

    2017-12-01

    Aerosols are found in a wide diversity of contexts and applications, including the atmosphere, pharmaceutics, and industry. Aerosols are dispersions of particles in a gas, and the coupling of the two phases results in highly dynamic systems where chemical and physical properties like size, composition, phase, and refractive index change rapidly in response to environmental perturbations. Aerosol particles span a wide range of sizes from 1 nm to tens of micrometres or from small molecular clusters that may more closely resemble gas phase molecules to large particles that can have similar qualities to bulk materials. However, even large particles with finite volumes exhibit distinct properties from the bulk condensed phase, due in part to their higher surface-to-volume ratio and their ability to easily access supersaturated solute states inaccessible in the bulk. Aerosols represent a major challenge for study because of the facile coupling between the particle and gas, the small amounts of sample available for analysis, and the sheer breadth of operative processes. Time scales of aerosol processes can be as short as nanoseconds or as long as years. Despite their very different impacts and applications, fundamental chemical physics processes serve as a common theme that underpins our understanding of aerosols. This perspective article discusses challenges in the study of aerosols and highlights recent chemical physics advancements that have enabled improved understanding of these complex systems.

  16. Environmental pollutants and aging: Investigating and modeling mechanisms of susceptibility in later life.

    EPA Science Inventory

    The rapidly expanding population of older adults raises new concerns over their potential vulnerability to environmental pollutants. Decreases in organ-system function and defenses, coupled with reduced metabolic capacity and clearance, are likely mechanisms for enhanced vulnerab...

  17. Investigating the Influence of Environmental Factors on Pesticide Exposure in Amphibians

    EPA Science Inventory

    Environmental factors such as temporal weather patterns and soil characterization coupled with pesticide application rates are known to influence exposure and subsequent absorption of these compounds in amphibians. Amphibians are a unique class of vertebrates due to their varied ...

  18. A Coupled Surface Nudging Scheme for use in Retrospective Weather and Climate Simulations for Environmental Applications

    EPA Science Inventory

    A surface analysis nudging scheme coupling atmospheric and land surface thermodynamic parameters has been implemented into WRF v3.8 (latest version) for use with retrospective weather and climate simulations, as well as for applications in air quality, hydrology, and ecosystem mo...

  19. Synchronization and information processing by an on-off coupling

    NASA Astrophysics Data System (ADS)

    Wei, G. W.; Zhao, Shan

    2002-05-01

    This paper proposes an on-off coupling process for chaos synchronization and information processing. An in depth analysis for the net effect of a conventional coupling is performed. The stability of the process is studied. We show that the proposed controlled coupling process can locally minimize the smoothness and the fidelity of dynamical data. A digital filter expression for the on-off coupling process is derived and a connection is made to the Hanning filter. The utility and robustness of the proposed approach is demonstrated by chaos synchronization in Duffing oscillators, the spatiotemporal synchronization of noisy nonlinear oscillators, the estimation of the trend of a time series, and restoration of the contaminated solution of the nonlinear Schrödinger equation.

  20. Treatment of electronic waste to recover metal values using thermal plasma coupled with acid leaching--a response surface modeling approach.

    PubMed

    Rath, Swagat S; Nayak, Pradeep; Mukherjee, P S; Roy Chaudhury, G; Mishra, B K

    2012-03-01

    The global crisis of the hazardous electronic waste (E-waste) is on the rise due to increasing usage and disposal of electronic devices. A process was developed to treat E-waste in an environmentally benign process. The process consisted of thermal plasma treatment followed by recovery of metal values through mineral acid leaching. In the thermal process, the E-waste was melted to recover the metal values as a metallic mixture. The metallic mixture was subjected to acid leaching in presence of depolarizer. The leached liquor mainly contained copper as the other elements like Al and Fe were mostly in alloy form as per the XRD and phase diagram studies. Response surface model was used to optimize the conditions for leaching. More than 90% leaching efficiency at room temperature was observed for Cu, Ni and Co with HCl as the solvent, whereas Fe and Al showed less than 40% efficiency. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Process Simulation of Aluminium Sheet Metal Deep Drawing at Elevated Temperatures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Winklhofer, Johannes; Trattnig, Gernot; Lind, Christoph

    Lightweight design is essential for an economic and environmentally friendly vehicle. Aluminium sheet metal is well known for its ability to improve the strength to weight ratio of lightweight structures. One disadvantage of aluminium is that it is less formable than steel. Therefore complex part geometries can only be realized by expensive multi-step production processes. One method for overcoming this disadvantage is deep drawing at elevated temperatures. In this way the formability of aluminium sheet metal can be improved significantly, and the number of necessary production steps can thereby be reduced. This paper introduces deep drawing of aluminium sheet metalmore » at elevated temperatures, a corresponding simulation method, a characteristic process and its optimization. The temperature and strain rate dependent material properties of a 5xxx series alloy and their modelling are discussed. A three dimensional thermomechanically coupled finite element deep drawing simulation model and its validation are presented. Based on the validated simulation model an optimised process strategy regarding formability, time and cost is introduced.« less

  2. Huyghens Engines--a new concept and its embodiment for nano-micro interlevel information processing.

    PubMed

    Santoli, Salvatore

    2009-02-01

    Current criteria in Bionanotechnology based on software and sensor/actuator hardware of Artificial Intelligence for bioinspired nanostructured systems lack the nanophysical background and key mathematics to describe and mimick the biological hierarchies of nano-to-micro-integrated informational/energetic levels. It is argued that bionanoscale hardware/software undividable solidarity can be mimicked by artificial nanostructured systems featuring intra/interlevel information processing through the emerging organization principle of quantum holography, described by the Heisenberg group G and by harmonic analysis on G. From a property of G as a Lie group, quantum holography is shown to merge the quantum/classical dynamic-symbolic ongoings into the structure-function unity of biological sensing-information processing-actuating, while by Ch. Huyghens' principles about wave motion and coupled oscillators synchronization it applies to environmental waves of any kind, so embodying a universal information processing engine, dubbed Huyghens Engine, that mimicks the holistic nanobiological structure-function solidarity and the kinetics/thermodynamics of nano/micro interface information transfer.

  3. A Review of the Research in Emotionally Focused Therapy for Couples.

    PubMed

    Wiebe, Stephanie A; Johnson, Susan M

    2016-09-01

    Emotionally Focused Therapy for Couples (EFT) is a brief evidence-based couple therapy based in attachment theory. Since the development of EFT, efficacy and effectiveness research has accumulated to address a range of couple concerns. EFT meets or exceeds the guidelines for classification as an evidence-based couple therapy outlined for couple and family research. Furthermore, EFT researchers have examined the process of change and predictors of outcome in EFT. Future research in EFT will continue to examine the process of change in EFT and test the efficacy and effectiveness of EFT in new applications and for couples of diverse backgrounds and concerns. © 2016 Family Process Institute.

  4. OpenFLUID: an open-source software environment for modelling fluxes in landscapes

    NASA Astrophysics Data System (ADS)

    Fabre, Jean-Christophe; Rabotin, Michaël; Crevoisier, David; Libres, Aline; Dagès, Cécile; Moussa, Roger; Lagacherie, Philippe; Raclot, Damien; Voltz, Marc

    2013-04-01

    Integrative landscape functioning has become a common concept in environmental management. Landscapes are complex systems where many processes interact in time and space. In agro-ecosystems, these processes are mainly physical processes, including hydrological-processes, biological processes and human activities. Modelling such systems requires an interdisciplinary approach, coupling models coming from different disciplines, developed by different teams. In order to support collaborative works, involving many models coupled in time and space for integrative simulations, an open software modelling platform is a relevant answer. OpenFLUID is an open source software platform for modelling landscape functioning, mainly focused on spatial fluxes. It provides an advanced object-oriented architecture allowing to i) couple models developed de novo or from existing source code, and which are dynamically plugged to the platform, ii) represent landscapes as hierarchical graphs, taking into account multi-scale, spatial heterogeneities and landscape objects connectivity, iii) run and explore simulations in many ways : using the OpenFLUID software interfaces for users (command line interface, graphical user interface), or using external applications such as GNU R through the provided ROpenFLUID package. OpenFLUID is developed in C++ and relies on open source libraries only (Boost, libXML2, GLib/GTK, OGR/GDAL, …). For modelers and developers, OpenFLUID provides a dedicated environment for model development, which is based on an open source toolchain, including the Eclipse editor, the GCC compiler and the CMake build system. OpenFLUID is distributed under the GPLv3 open source license, with a special exception allowing to plug existing models licensed under any license. It is clearly in the spirit of sharing knowledge and favouring collaboration in a community of modelers. OpenFLUID has been involved in many research applications, such as modelling of hydrological network transfer, diagnosis and prediction of water quality taking into account human activities, study of the effect of spatial organization on hydrological fluxes, modelling of surface-subsurface water exchanges, … At LISAH research unit, OpenFLUID is the supporting development platform of the MHYDAS model, which is a distributed model for agrosystems (Moussa et al., 2002, Hydrological Processes, 16, 393-412). OpenFLUID web site : http://www.openfluid-project.org

  5. The effects of corn zein protein coupling agent on mechanical properties of flax fiber reinforced composites

    NASA Astrophysics Data System (ADS)

    Whitacre, Ryan John

    In the field of renewable materials, natural fiber composites demonstrate the capacity to be a viable structural material. When normalized by density, flax fiber mechanical properties are competitive with E-glass fibers. However, the hydrophilic nature of flax fibers reduces the interfacial bond strength with polymer thermosets, limiting composite mechanical properties. Corn zein protein was selected as a natural bio-based coupling agent because of its combination of hydrophobic and hydrophilic properties. Zein was deposited on the surface of flax, which was then processed into unidirectional composite. The mechanical properties of zein treated samples where measured and compared against commonly utilized synthetic treatments sodium hydroxide and silane which incorporate harsh chemicals. Fourier transform infrared spectroscopy, chemical analysis, and scanning electron microscopy were also used to determine analyze zein treatments. Results demonstrate the environmentally friendly zein treatment successfully increased tensile strength 8%, flexural strength 17%, and shear strength 30% compared to untreated samples.

  6. Biological treatment of fracturing waste liquid in a membrane-coupled internal circulation aerobic biological fluidized bed with the assistance of coagulation.

    PubMed

    Tu, Yizhou; Liu, Xing-Peng; Li, Hui-Qiang; Yang, Ping

    2017-12-01

    Fracturing waste liquid (FWL) is generated during shale gas extraction and contains high concentrations of suspended solid, salinity and organic compounds, which needs proper management to prevent excessive environmental disruption. Biological treatment of the FWL was attempted in this study using a membrane-coupled internal circulation aerobic biological fluidized bed (MC-ICABFB) after being treated by coagulation. The results showed that poly aluminum chloride (PAC) of 30 g/L, polyacrylamide (PAM) of 20 mg/L and pH of 7.0 were suitable choices for coagulation. The pretreated FWL mixed with synthetic wastewater at different ratios were used as the influent wastewater for the reactor. The MC-ICABFB had relatively good performance on COD and NH 4 + -N removal and the main residual organic compound in the effluent was phthalates according to the analysis of GC-MC profiles. In addition, a suitable pretreatment process for the FWL to facilitate biological treatment of the wastewater needs further research.

  7. Statistical mechanics of tuned cell signalling: sensitive collective response by synthetic biological circuits

    NASA Astrophysics Data System (ADS)

    Voliotis, M.; Liverpool, T. B.

    2017-03-01

    Living cells sense and process environmental cues through noisy biochemical mechanisms. This apparatus limits the scope of engineering cells as viable sensors. Here, we highlight a mechanism that enables robust, population-wide responses to external stimulation based on cellular communication, known as quorum sensing. We propose a synthetic circuit consisting of two mutually repressing quorum sensing modules. At low cell densities the system behaves like a genetic toggle switch, while at higher cell densities the behaviour of nearby cells is coupled via diffusible quorum sensing molecules. We show by systematic coarse graining that at large length and timescales that the system can be described using the Ising model of a ferromagnet. Thus, in analogy with magnetic systems, the sensitivity of the population-wide response, or its ‘susceptibility’ to a change in the external signal, is highly enhanced for a narrow range of cell-cell coupling close to a critical value. We expect that our approach will be used to enhance the sensitivity of synthetic bio-sensing networks.

  8. Achieving Simultaneous CO2 and H2 S Conversion via a Coupled Solar-Driven Electrochemical Approach on Non-Precious-Metal Catalysts.

    PubMed

    Ma, Weiguang; Wang, Hong; Yu, Wei; Wang, Xiaomei; Xu, Zhiqiang; Zong, Xu; Li, Can

    2018-03-19

    Carbon dioxide (CO 2 ) and hydrogen sulfide (H 2 S) are generally concomitant with methane (CH 4 ) in natural gas and traditionally deemed useless or even harmful. Developing strategies that can simultaneously convert both CO 2 and H 2 S into value-added products is attractive; however it has not received enough attention. A solar-driven electrochemical process is demonstrated using graphene-encapsulated zinc oxide catalyst for CO 2 reduction and graphene catalyst for H 2 S oxidation mediated by EDTA-Fe 2+ /EDTA-Fe 3+ redox couples. The as-prepared solar-driven electrochemical system can realize the simultaneous conversion of CO 2 and H 2 S into carbon monoxide and elemental sulfur at near neutral conditions with high stability and selectivity. This conceptually provides an alternative avenue for the purification of natural gas with added economic and environmental benefits. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Enantio-Relay Catalysis Constructs Chiral Biaryl Alcohols over Cascade Suzuki Cross-Coupling-Asymmetric Transfer Hydrogenation

    NASA Astrophysics Data System (ADS)

    Zhang, Dacheng; Gao, Xiaoshuang; Cheng, Tanyu; Liu, Guohua

    2014-05-01

    The construction of chiral biaryl alcohols using enantio-relay catalysis is a particularly attractive synthetic method in organic synthesis. However, overcoming the intrinsic incompatibility of distinct organometallic complexes and the reaction conditions used are significant challenges in asymmetric catalysis. To overcome these barriers, we have taken advantage of an enantio-relay catalysis strategy and a combined dual-immobilization approach. We report the use of an imidazolium-based organopalladium-functionalized organic-inorganic hybrid silica and ethylene-coated chiral organoruthenium-functionalized magnetic nanoparticles to catalyze a cascade Suzuki cross-coupling-asymmetric transfer hydrogenation reaction to prepare chiral biaryl alcohols in a two-step, one-pot process. As expected, the site-isolated active species, salient imidazolium phase-transfer character and high ethylene-coated hydrophobicity can synergistically boost the catalytic performance. Furthermore, enantio-relay catalysis has the potential to efficiently prepare a variety of chiral biaryl alcohols. Our synthetic strategy is a general method that shows the potential of developing enantio-relay catalysis towards environmentally benign and sustainable organic synthesis.

  10. Cavity-based architecture to preserve quantum coherence and entanglement

    NASA Astrophysics Data System (ADS)

    Man, Zhong-Xiao; Xia, Yun-Jie; Lo Franco, Rosario

    2015-09-01

    Quantum technology relies on the utilization of resources, like quantum coherence and entanglement, which allow quantum information and computation processing. This achievement is however jeopardized by the detrimental effects of the environment surrounding any quantum system, so that finding strategies to protect quantum resources is essential. Non-Markovian and structured environments are useful tools to this aim. Here we show how a simple environmental architecture made of two coupled lossy cavities enables a switch between Markovian and non-Markovian regimes for the dynamics of a qubit embedded in one of the cavity. Furthermore, qubit coherence can be indefinitely preserved if the cavity without qubit is perfect. We then focus on entanglement control of two independent qubits locally subject to such an engineered environment and discuss its feasibility in the framework of circuit quantum electrodynamics. With up-to-date experimental parameters, we show that our architecture allows entanglement lifetimes orders of magnitude longer than the spontaneous lifetime without local cavity couplings. This cavity-based architecture is straightforwardly extendable to many qubits for scalability.

  11. Cavity-based architecture to preserve quantum coherence and entanglement.

    PubMed

    Man, Zhong-Xiao; Xia, Yun-Jie; Lo Franco, Rosario

    2015-09-09

    Quantum technology relies on the utilization of resources, like quantum coherence and entanglement, which allow quantum information and computation processing. This achievement is however jeopardized by the detrimental effects of the environment surrounding any quantum system, so that finding strategies to protect quantum resources is essential. Non-Markovian and structured environments are useful tools to this aim. Here we show how a simple environmental architecture made of two coupled lossy cavities enables a switch between Markovian and non-Markovian regimes for the dynamics of a qubit embedded in one of the cavity. Furthermore, qubit coherence can be indefinitely preserved if the cavity without qubit is perfect. We then focus on entanglement control of two independent qubits locally subject to such an engineered environment and discuss its feasibility in the framework of circuit quantum electrodynamics. With up-to-date experimental parameters, we show that our architecture allows entanglement lifetimes orders of magnitude longer than the spontaneous lifetime without local cavity couplings. This cavity-based architecture is straightforwardly extendable to many qubits for scalability.

  12. Acidification at the Surface in the East Sea: A Coupled Climate-carbon Cycle Model Study

    NASA Astrophysics Data System (ADS)

    Park, Young-Gyu; Seol, Kyung-Hee; Boo, Kyung-On; Lee, Johan; Cho, Chunho; Byun, Young-Hwa; Seo, Seongbong

    2018-05-01

    This modeling study investigates the impacts of increasing atmospheric CO2 concentration on acidification in the East Sea. A historical simulation for the past three decades (1980 to 2010) was performed using the Hadley Centre Global Environmental Model (version 2), a coupled climate model with atmospheric, terrestrial and ocean cycles. As the atmospheric CO2 concentration increased, acidification progressed in the surface waters of the marginal sea. The acidification was similar in magnitude to observations and models of acidification in the global ocean. However, in the global ocean, the acidification appears to be due to increased in-situ oceanic CO2 uptake, whereas local processes had stronger effects in the East Sea. pH was lowered by surface warming and by the influx of water with higher dissolved inorganic carbon (DIC) from the northwestern Pacific. Due to the enhanced advection of DIC, the partial pressure of CO2 increased faster than in the overlying air; consequently, the in-situ oceanic uptake of CO2 decreased.

  13. Cavity-based architecture to preserve quantum coherence and entanglement

    PubMed Central

    Man, Zhong-Xiao; Xia, Yun-Jie; Lo Franco, Rosario

    2015-01-01

    Quantum technology relies on the utilization of resources, like quantum coherence and entanglement, which allow quantum information and computation processing. This achievement is however jeopardized by the detrimental effects of the environment surrounding any quantum system, so that finding strategies to protect quantum resources is essential. Non-Markovian and structured environments are useful tools to this aim. Here we show how a simple environmental architecture made of two coupled lossy cavities enables a switch between Markovian and non-Markovian regimes for the dynamics of a qubit embedded in one of the cavity. Furthermore, qubit coherence can be indefinitely preserved if the cavity without qubit is perfect. We then focus on entanglement control of two independent qubits locally subject to such an engineered environment and discuss its feasibility in the framework of circuit quantum electrodynamics. With up-to-date experimental parameters, we show that our architecture allows entanglement lifetimes orders of magnitude longer than the spontaneous lifetime without local cavity couplings. This cavity-based architecture is straightforwardly extendable to many qubits for scalability. PMID:26351004

  14. Potential roles of anaerobic ammonium and methane oxidation in the nitrogen cycle of wetland ecosystems.

    PubMed

    Zhu, Guibing; Jetten, Mike S M; Kuschk, Peter; Ettwig, Katharina F; Yin, Chengqing

    2010-04-01

    Anaerobic ammonium oxidation (anammox) and anaerobic methane oxidation (ANME coupled to denitrification) with nitrite as electron acceptor are two of the most recent discoveries in the microbial nitrogen cycle. Currently the anammox process has been relatively well investigated in a number of natural and man-made ecosystems, while ANME coupled to denitrification has only been observed in a limited number of freshwater ecosystems. The ubiquitous presence of anammox bacteria in marine ecosystems has changed our knowledge of the global nitrogen cycle. Up to 50% of N(2) production in marine sediments and oxygen-depleted zones may be attributed to anammox bacteria. However, there are only few indications of anammox in natural and constructed freshwater wetlands. In this paper, the potential role of anammox and denitrifying methanotrophic bacteria in natural and artificial wetlands is discussed in relation to global warming. The focus of the review is to explore and analyze if suitable environmental conditions exist for anammox and denitrifying methanotrophic bacteria in nitrogen-rich freshwater wetlands.

  15. UK Environmental Prediction - integration and evaluation at the convective scale

    NASA Astrophysics Data System (ADS)

    Fallmann, Joachim; Lewis, Huw; Castillo, Juan Manuel; Pearson, David; Harris, Chris; Saulter, Andy; Bricheno, Lucy; Blyth, Eleanor

    2016-04-01

    Traditionally, the simulation of regional ocean, wave and atmosphere components of the Earth System have been considered separately, with some information on other components provided by means of boundary or forcing conditions. More recently, the potential value of a more integrated approach, as required for global climate and Earth System prediction, for regional short-term applications has begun to gain increasing research effort. In the UK, this activity is motivated by an understanding that accurate prediction and warning of the impacts of severe weather requires an integrated approach to forecasting. The substantial impacts on individuals, businesses and infrastructure of such events indicate a pressing need to understand better the value that might be delivered through more integrated environmental prediction. To address this need, the Met Office, NERC Centre for Ecology & Hydrology and NERC National Oceanography Centre have begun to develop the foundations of a coupled high resolution probabilistic forecast system for the UK at km-scale. This links together existing model components of the atmosphere, coastal ocean, land surface and hydrology. Our initial focus has been on a 2-year Prototype project to demonstrate the UK coupled prediction concept in research mode. This presentation will provide an update on UK environmental prediction activities. We will present the results from the initial implementation of an atmosphere-land-ocean coupled system, including a new eddy-permitting resolution ocean component, and discuss progress and initial results from further development to integrate wave interactions in this relatively high resolution system. We will discuss future directions and opportunities for collaboration in environmental prediction, and the challenges to realise the potential of integrated regional coupled forecasting for improving predictions and applications.

  16. The present triumphs and future problems with wave soldering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vianco, P.T.

    1993-10-01

    Nearly 40 years of experience with wave soldering have resulted in processes that routinely produce several thousand, defect-free solder joints per minute. However, the climate of electronics manufacturing has changed significantly over the past 10 to 15 years. Environmental restrictions as well as the high quality of products made offshore has placed new demands and challenges on the electronics industry, right down to the assembly process. The impact on wave soldering by environmental regulations and a need for more cost-competitive manufacturing processes has become a serious issue in terms of the economical well-being of the industry. In order to obtainmore » a clearer understanding of the situation, however, it is first most appropriate and necessary to examine the technology of wave soldering. Historically, wave soldering was developed as a refinement of the dip and drag soldering processes with the objective of reducing or eliminating many of the associated defects often present in these earlier processes. Wave soldering reduces the area of contact between the circuit board and the solder. This characteristic, coupled with the agitation generated in the solder, allows flux and its volatile by-products to readily escape from under the board, decreasing the number of skips, unfilled holes, and solder joint voids. The reduced contact area also lessens the potential for thermal damage to the circuit board laminate. Control of the wave profile at the exit point of the circuit board lessens the likelihood of icicles and bridges forming on the solder joints; this latitude is not available in the dip soldering process.« less

  17. Reactivity of biogenic manganese oxide for metal sequestration and photochemistry: Computational solid state physics study (in Korean)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kwon, K.D.; Sposito, G.

    2010-02-01

    Many microbes, including both bacteria and fungi, produce manganese (Mn) oxides by oxidizing soluble Mn(II) to form insoluble Mn(IV) oxide minerals, a kinetically much faster process than abiotic oxidation. These biogenic Mn oxides drive the Mn cycle, coupling it with diverse biogeochemical cycles and determining the bioavailability of environmental contaminants, mainly through strong adsorption and redox reactions. This mini review introduces recent findings based on quantum mechanical density functional theory that reveal the detailed mechanisms of toxic metal adsorption at Mn oxide surfaces and the remarkable role of Mn vacancies in the photochemistry of these minerals.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tian, Hanqin; Chen, Guangsheng; Lu, Chaoqun

    Greenhouse gas (GHG)-induced climate change is among the most pressing sustainability challenges facing humanity today, posing serious risks for ecosystem health. Methane (CH 4) and nitrous oxide (N 2O) are the two most important GHGs after carbon dioxide (CO 2), but their regional and global budgets are not well known. In this paper, we applied a process-based coupled biogeochemical model to concurrently estimate the magnitude and spatial and temporal patterns of CH 4 and N 2O fluxes as driven by multiple environmental changes, including climate variability, rising atmospheric CO 2, increasing nitrogen deposition, tropospheric ozone pollution, land use change, andmore » nitrogen fertilizer use.« less

  19. Remediation of Groundwater Contaminated by Nuclear Waste

    NASA Astrophysics Data System (ADS)

    Parker, Jack; Palumbo, Anthony

    2008-07-01

    A Workshop on Accelerating Development of Practical Field-Scale Bioremediation Models; An Online Meeting, 23 January to 20 February 2008; A Web-based workshop sponsored by the U.S. Department of Energy Environmental Remediation Sciences Program (DOE/ERSP) was organized in early 2008 to assess the state of the science and knowledge gaps associated with the use of computer models to facilitate remediation of groundwater contaminated by wastes from Cold War era nuclear weapons development and production. Microbially mediated biological reactions offer a potentially efficient means to treat these sites, but considerable uncertainty exists in the coupled biological, chemical, and physical processes and their mathematical representation.

  20. Environmental niche divergence among three dune shrub sister species with parapatric distributions.

    PubMed

    Chozas, Sergio; Chefaoui, Rosa M; Correia, Otília; Bonal, Raúl; Hortal, Joaquín

    2017-05-01

    The geographical distributions of species are constrained by their ecological requirements. The aim of this work was to analyse the effects of environmental conditions, historical events and biogeographical constraints on the diversification of the three species of the western Mediterranean shrub genus Stauracanthus , which have a parapatric distribution in the Iberian Peninsula. Ecological niche factor analysis and generalized linear models were used to measure the response of all Stauracanthus species to the environmental gradients and map their potential distributions in the Iberian Peninsula. The bioclimatic niche overlap between the three species was determined by using Schoener's index. The genetic differentiation of the Iberian and northern African populations of Stauracanthus species was characterized with GenalEx. The effects on genetic distances of the most important environmental drivers were assessed through Mantel tests and non-metric multidimensional scaling. The three Stauracanthus species show remarkably similar responses to climatic conditions. This supports the idea that all members of this recently diversified clade retain common adaptations to climate and consequently high levels of climatic niche overlap. This contrasts with the diverse edaphic requirements of Stauracanthus species. The populations of the S. genistoides-spectabilis clade grow on Miocene and Pliocene fine-textured sedimentary soils, whereas S. boivinii , the more genetically distant species, occurs on older and more coarse-textured sedimentary substrates. These patterns of diversification are largely consistent with a stochastic process of geographical range expansion and fragmentation coupled with niche evolution in the context of spatially complex environmental fluctuations. : The combined analysis of the distribution, realized environmental niche and phylogeographical relationships of parapatric species proposed in this work allows integration of the biogeographical, ecological and evolutionary processes driving the evolution of species adaptations and how they determine their current geographical ranges. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  1. Application of inductively coupled plasma sector field mass spectrometry for low-level environmental americium-241 analysis.

    PubMed

    Varga, Zsolt

    2007-03-28

    An improved and novel sample preparation method for (241)Am analysis by inductively coupled plasma sector field mass spectrometry has been developed. The procedure involves a selective CaF(2) pre-concentration followed by an extraction chromatographic separation using TRU resin. The achieved absolute detection limit of 0.86 fg (0.11 mBq) is comparable to that of alpha spectrometry (0.1 mBq) and suitable for low-level environmental measurements. Analysis of different kinds of environmental standard reference materials (IAEA-384--Fangataufa lagoon sediment, IAEA-385--Irish Sea sediment and IAEA-308--Mixed seaweed from the Mediterranean Sea) and alpha spectrometry were used to validate the procedure. The chemical recovery of sample preparation ranged between 72 and 94%. The results obtained are in good agreement with reference values and those measured by alpha spectrometry. The proposed method offers a rapid and less labor-intensive possibility for environmental (241)Am analysis than the conventionally applied radioanalytical techniques.

  2. Verification of geomechanical integrity and prediction of long-term mineral trapping for the Ketzin CO2 storage pilot site

    NASA Astrophysics Data System (ADS)

    Kempka, Thomas; De Lucia, Marco; Kühn, Michael

    2014-05-01

    Static and dynamic numerical modelling generally accompany the entire CO2 storage site life cycle. Thereto, it is required to match the employed models with field observations on a regular basis in order to predict future site behaviour. We investigated the coupled processes at the Ketzin CO2 storage pilot site [1] using a model coupling concept focusing on the temporal relevance of processes involved (hydraulic, chemical and mechanical) at given time-scales (site operation, abandonment and long-term stabilization). For that purpose, long-term dynamic multi-phase flow simulations [2], [3] established the basis for all simulations discussed in the following. Hereby, pressure changes resulting in geomechanical effects are largest during site operation, whereas geochemical reactions are governed by slow kinetics resulting in a long-term stabilization. To account for mechanical integrity, which may be mainly affected during site operation, we incorporated a regional-scale coupled hydro-mechanical model. Our simulation results show maximum ground surface displacements of about 4 mm, whereas shear and tensile failure are not observed. Consequently, the CO2 storage operation at the Ketzin pilot site does not compromise reservoir, caprock and fault integrity. Chemical processes responsible for mineral trapping are expected to mainly occur during long-term stabilization at the Ketzin pilot site [4]. Hence, our previous assessment [3] was extended by integrating two long-term mineral trapping scenarios. Thereby, mineral trapping contributes to the trapping mechanisms with 11.7 % after 16,000 years of simulation in our conservative and with 30.9 % in our maximum reactivity scenarios. Dynamic flow simulations indicate that only 0.2 % of the CO2 injected (about 67,270 t CO2 in total) is in gaseous state, but structurally trapped after 16,000 years. Depending on the studied long-term scenario, CO2 dissolution is the dominating trapping mechanism with 68.9 % and 88.1 %, respectively. We verified the mechanical integrity of the storage system during site operation and predicted the trapping mechanisms for the Ketzin pilot site based on a time-dependent integration of relevant processes for a time period of 16,000 years. Supported by our coupled modelling results, we conclude that CO2 storage at the Ketzin site is safe and reliable on the pilot scale. References [1] Martens, S., Kempka, T., Liebscher, A., Lüth, S., Möller, F., Myrttinen, A., Norden, B., Schmidt-Hattenberger, C., Zimmer, M., Kühn, M. Europe's longest-operating on-shore CO2 storage site at Ketzin, Germany: a progress report after three years of injection. Environmental Earth Sciences 2012 67(2): 323-334. [2] Kempka, T., Kühn, M. Numerical simulations of CO2 arrival times and reservoir pressure coincide with observations from the Ketzin pilot site, Germany. Environmental Earth Sciences 2013 70(8): 3675-3685. [3] Kempka, T., Klein, E., De Lucia, M., Tillner, E., Kühn, M. Assessment of Long-term CO2 Trapping Mechanisms at the Ketzin Pilot Site (Germany) by Coupled Numerical Modelling. Energy Procedia 2013 37: 5419-5426. [4] Klein, E., De Lucia, M., Kempka, T., Kühn, M. Evaluation of long-term mineral trapping at the Ketzin pilot site for CO2 storage: An integrative approach using geochemical modelling and reservoir simulation. International Journal of Greenhouse Gas Control 2013 19: 720-730.

  3. Nanostructured copper-coated solid-phase microextraction fiber for gas chromatographic analysis of dibutyl phthalate and diethylhexyl phthalate environmental estrogens.

    PubMed

    Feng, Juanjuan; Sun, Min; Bu, Yanan; Luo, Chuannan

    2015-01-01

    A novel nanostructured copper-based solid-phase microextraction fiber was developed and applied for determining the two most common types of phthalate environmental estrogens (dibutyl phthalate and diethylhexyl phthalate) in aqueous samples, coupled to gas chromatography with flame ionization detection. The copper film was coated onto a stainless-steel wire via an electroless plating process, which involved a surface activation process to improve the surface properties of the fiber. Several parameters affecting extraction efficiency such as extraction time, extraction temperature, ionic strength, desorption temperature, and desorption time were optimized by a factor-by-factor procedure to obtain the highest extraction efficiency. The as-established method showed wide linear ranges (0.05-250 μg/L). Precision of single fiber repeatability was <7.0%, and fiber-to-fiber repeatability was <10%. Limits of detection were 0.01 μg/L. The proposed method exhibited better or comparable extraction performance compared with commercial and other lab-made fibers, and excellent thermal stability and durability. The proposed method was applied successfully for the determination of model analytes in plastic soaking water. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Rapid extraction and assay of uranium from environmental surface samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barrett, Christopher A.; Chouyyok, Wilaiwan; Speakman, Robert J.

    Extraction methods enabling faster removal and concentration of uranium compounds for improved trace and low-level assay are demonstrated for standard surface sampling material in support of nuclear safeguards efforts, health monitoring, and other nuclear analysis applications. A key problem with the existing surface sampling swipes is the requirement for complete digestion of sample and sampling matrix. This is a time-consuming and labour-intensive process that limits laboratory throughput, elevates costs, and increases background levels. Various extraction methods are explored for their potential to quickly and efficiently remove different chemical forms of uranium from standard surface sampling material. A combination of carbonatemore » and peroxide solutions is shown to give the most rapid and complete form of uranyl compound extraction and dissolution. This rapid extraction process is demonstrated to be compatible with standard inductive coupled plasma mass spectrometry methods for uranium isotopic assay as well as screening techniques such as x-ray fluorescence. The general approach described has application beyond uranium to other analytes of nuclear forensic interest (e.g., rare earth elements and plutonium) as well as heavy metals for environmental and industrial hygiene monitoring.« less

  5. Cooperation in microbial communities and their biotechnological applications

    PubMed Central

    Cavaliere, Matteo; Feng, Song; Soyer, Orkun S.

    2017-01-01

    Summary Microbial communities are increasingly utilized in biotechnology. Efficiency and productivity in many of these applications depends on the presence of cooperative interactions between members of the community. Two key processes underlying these interactions are the production of public goods and metabolic cross‐feeding, which can be understood in the general framework of ecological and evolutionary (eco‐evo) dynamics. In this review, we illustrate the relevance of cooperative interactions in microbial biotechnological processes, discuss their mechanistic origins and analyse their evolutionary resilience. Cooperative behaviours can be damaged by the emergence of ‘cheating’ cells that benefit from the cooperative interactions but do not contribute to them. Despite this, cooperative interactions can be stabilized by spatial segregation, by the presence of feedbacks between the evolutionary dynamics and the ecology of the community, by the role of regulatory systems coupled to the environmental conditions and by the action of horizontal gene transfer. Cooperative interactions enrich microbial communities with a higher degree of robustness against environmental stress and can facilitate the evolution of more complex traits. Therefore, the evolutionary resilience of microbial communities and their ability to constraint detrimental mutants should be considered to design robust biotechnological applications. PMID:28447371

  6. Developing predictive insight into changing water systems: use-inspired hydrologic science for the Anthropocene

    NASA Astrophysics Data System (ADS)

    Thompson, S. E.; Sivapalan, M.; Harman, C. J.; Srinivasan, V.; Hipsey, M. R.; Reed, P.; Montanari, A.; Blöschl, G.

    2013-06-01

    Globally, many different kinds of water resources management issues call for policy and infrastructure based responses. Yet responsible decision making about water resources management raises a fundamental challenge for hydrologists: making predictions about water resources on decadal-to-century long timescales. Obtaining insight into hydrologic futures over 100 yr timescales forces researchers to address internal and exogenous changes in the properties of hydrologic systems. To do this, new hydrologic research must identify, describe and model feedbacks between water and other changing, coupled environmental subsystems. These models must be constrained to yield useful insights, despite the many likely sources of uncertainty in their predictions. Chief among these uncertainties are the impacts of the increasing role of human intervention in the global water cycle - a defining challenge for hydrology in the Anthropocene. Here we present a research agenda that proposes a suite of strategies to address these challenges. The research agenda focuses on the development of co-evolutionary hydrologic modeling to explore coupling across systems, and to address the implications of this coupling on the long-time behavior of the coupled systems. Three research directions support the development of these models: hydrologic reconstruction, comparative hydrology and model-data learning. These strategies focus on understanding hydrologic processes and feedbacks over long timescales, across many locations, and through strategic coupling of observational and model data in specific systems. We highlight the value of use-inspired and team-based science that is motivated by real-world hydrologic problems but targets improvements in fundamental understanding to support decision-making and management.

  7. A General-purpose Framework for Parallel Processing of Large-scale LiDAR Data

    NASA Astrophysics Data System (ADS)

    Li, Z.; Hodgson, M.; Li, W.

    2016-12-01

    Light detection and ranging (LiDAR) technologies have proven efficiency to quickly obtain very detailed Earth surface data for a large spatial extent. Such data is important for scientific discoveries such as Earth and ecological sciences and natural disasters and environmental applications. However, handling LiDAR data poses grand geoprocessing challenges due to data intensity and computational intensity. Previous studies received notable success on parallel processing of LiDAR data to these challenges. However, these studies either relied on high performance computers and specialized hardware (GPUs) or focused mostly on finding customized solutions for some specific algorithms. We developed a general-purpose scalable framework coupled with sophisticated data decomposition and parallelization strategy to efficiently handle big LiDAR data. Specifically, 1) a tile-based spatial index is proposed to manage big LiDAR data in the scalable and fault-tolerable Hadoop distributed file system, 2) two spatial decomposition techniques are developed to enable efficient parallelization of different types of LiDAR processing tasks, and 3) by coupling existing LiDAR processing tools with Hadoop, this framework is able to conduct a variety of LiDAR data processing tasks in parallel in a highly scalable distributed computing environment. The performance and scalability of the framework is evaluated with a series of experiments conducted on a real LiDAR dataset using a proof-of-concept prototype system. The results show that the proposed framework 1) is able to handle massive LiDAR data more efficiently than standalone tools; and 2) provides almost linear scalability in terms of either increased workload (data volume) or increased computing nodes with both spatial decomposition strategies. We believe that the proposed framework provides valuable references on developing a collaborative cyberinfrastructure for processing big earth science data in a highly scalable environment.

  8. Evaluation of new alternatives in wastewater treatment plants based on dynamic modelling and life cycle assessment (DM-LCA).

    PubMed

    Bisinella de Faria, A B; Spérandio, M; Ahmadi, A; Tiruta-Barna, L

    2015-11-01

    With a view to quantifying the energy and environmental advantages of Urine Source-Separation (USS) combined with different treatment processes, five wastewater treatment plant (WWTP) scenarios were compared to a reference scenario using Dynamic Modelling (DM) and Life Cycle Assessment (LCA), and an integrated DM-LCA framework was thus developed. Dynamic simulations were carried out in BioWin(®) in order to obtain a realistic evaluation of the dynamic behaviour and performance of plants under perturbation. LCA calculations were performed within Umberto(®) using the Ecoinvent database. A Python™ interface was used to integrate and convert simulation data and to introduce them into Umberto(®) to achieve a complete LCA evaluation comprising foreground and background processes. Comparisons between steady-state and dynamic simulations revealed the importance of considering dynamic aspects such as nutrient and flow peaks. The results of the evaluation highlighted the potential of the USS scenario for nutrient recovery whereas the Enhanced Primary Clarification (EPC) scenario gave increased biogas production and also notably decreased aeration consumption, leading to a positive energy balance. Both USS and EPC scenarios also showed increased stability of plant operation, with smaller daily averages of total nitrogen and phosphorus. In this context, USS and EPC results demonstrated that the coupled USS + EPC scenario and its combinations with agricultural spreading of N-rich effluent and nitritation/anaerobic deammonification could present an energy-positive balance with respectively 27% and 33% lower energy requirements and an increase in biogas production of 23%, compared to the reference scenario. The coupled scenarios also presented lesser environmental impacts (reduction of 31% and 39% in total endpoint impacts) along with effluent quality well within the specified limits. The marked environmental performance (reduction of global warming) when nitrogen is used in agriculture shows the importance of future research on sustainable solutions for nitrogen recovery. The contribution analysis of midpoint impacts also showed hotspots that it will be important to optimize further, such as plant infrastructure and direct N2O emissions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Addressing the impact of environmental uncertainty in plankton model calibration with a dedicated software system: the Marine Model Optimization Testbed (MarMOT 1.1 alpha)

    NASA Astrophysics Data System (ADS)

    Hemmings, J. C. P.; Challenor, P. G.

    2012-04-01

    A wide variety of different plankton system models have been coupled with ocean circulation models, with the aim of understanding and predicting aspects of environmental change. However, an ability to make reliable inferences about real-world processes from the model behaviour demands a quantitative understanding of model error that remains elusive. Assessment of coupled model output is inhibited by relatively limited observing system coverage of biogeochemical components. Any direct assessment of the plankton model is further inhibited by uncertainty in the physical state. Furthermore, comparative evaluation of plankton models on the basis of their design is inhibited by the sensitivity of their dynamics to many adjustable parameters. Parameter uncertainty has been widely addressed by calibrating models at data-rich ocean sites. However, relatively little attention has been given to quantifying uncertainty in the physical fields required by the plankton models at these sites, and tendencies in the biogeochemical properties due to the effects of horizontal processes are often neglected. Here we use model twin experiments, in which synthetic data are assimilated to estimate a system's known "true" parameters, to investigate the impact of error in a plankton model's environmental input data. The experiments are supported by a new software tool, the Marine Model Optimization Testbed, designed for rigorous analysis of plankton models in a multi-site 1-D framework. Simulated errors are derived from statistical characterizations of the mixed layer depth, the horizontal flux divergence tendencies of the biogeochemical tracers and the initial state. Plausible patterns of uncertainty in these data are shown to produce strong temporal and spatial variability in the expected simulation error variance over an annual cycle, indicating variation in the significance attributable to individual model-data differences. An inverse scheme using ensemble-based estimates of the simulation error variance to allow for this environment error performs well compared with weighting schemes used in previous calibration studies, giving improved estimates of the known parameters. The efficacy of the new scheme in real-world applications will depend on the quality of statistical characterizations of the input data. Practical approaches towards developing reliable characterizations are discussed.

  10. Nordic couples' decision-making processes during assisted reproduction treatments.

    PubMed

    Sol Olafsdottir, Helga; Wikland, Matts; Möller, Anders

    2013-06-01

    To study couples' perceptions of their decision-making process during the first three years of infertility treatments. This study is a part of a larger project studying the decision-making processes of 22 infertile heterosexual couples, recruited from fertility clinics in all five Nordic countries, over a three year period. A descriptive qualitative method was used. Process of decision-making during assisted reproduction treatments. Seventeen couples had succeeded in becoming parents after approximately three years. Our study suggests that the decision-making process during fertility treatments has three phases: (i) recognizing the decisions to be made, with subcategories; the driving force, mutual project, (ii) gathering knowledge and experience about the options, with subcategories; trust, patient competence, personalized support, and (iii) adapting decisions to possible options, with subcategories; strategic planning, adaption. The core category was "maintaining control in a situation of uncertainty." Two parallel processes affect couples' decision-making process, one within themselves and their relationship, and the other in their contact with the fertility clinic. Couples struggle to make decisions, trusting clinic personnel for guidance, knowledge, and understanding. Nevertheless, couples expressed disappointment with the clinics' reactions to their requests for shared decision-making. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Characterization of the Decision Network for Wing Expansion in Drosophila Using Targeted Expression of the TRPM8 Channel

    PubMed Central

    Peabody, Nathan C.; Pohl, Jascha B.; Diao, Fengqiu; Vreede, Andrew P.; Sandstrom, David J.; Wang, Howard; Zelensky, Paul K.; White, Benjamin H.

    2009-01-01

    After emergence, adult flies and other insects select a suitable perch and expand their wings. Wing expansion is governed by the hormone bursicon and can be delayed under adverse environmental conditions. How environmental factors delay bursicon release and alter perch selection and expansion behaviors has not been investigated in detail. Here we provide evidence that in Drosophila the motor programs underlying perch selection and wing expansion have different environmental dependencies. Using physical manipulations, we demonstrate that the decision to perch is based primarily on environmental valuations and is incrementally delayed under conditions of increasing perturbation and confinement. In contrast, the all-or-none motor patterns underlying wing expansion are relatively invariant in length regardless of environmental conditions. Using a novel technique for targeted activation of neurons, we show that the highly stereotyped wing expansion motor patterns can be initiated by stimulation of NCCAP, a small network of central neurons that regulates the release of bursicon. Activation of this network using the cold-sensitive rat TRPM8 channel is sufficient to trigger all essential behavioral and somatic processes required for wing expansion. The delay of wing expansion under adverse circumstances thus couples an environmentally-sensitive decision network to a command-like network that initiates a fixed action pattern. Because NCCAP mediates environmentally-insensitive ecdysis-related behaviors in Drosophila development prior to adult emergence, the study of wing expansion promises insights not only into how networks mediate behavioral choices, but also into how decision networks develop. PMID:19295141

  12. Spatially resolved, in-situ monitoring of crack growth via the coupling current in aluminum alloy 5083

    NASA Astrophysics Data System (ADS)

    Williams, Krystaufeux D.

    The work discussed in this dissertation is an experimental validation of a body of research that was created to model stress corrosion cracking phenomenon for 304 stainless steels in boiling water reactors. This coupled environment fracture model (CEFM) incorporates the natural laws of the conservation of charge and the differential aeration hypothesis to predict the amount of stress corrosion crack growth as a function of many external environmental variables, including potential, stress intensity, solution conductivity, oxidizer concentrations, and various other environmental parameters. Out of this approach came the concept of the coupling current; a local corrosion current that flows from within cracks, crevices, pits, etc... of a metal or alloy to the external surface. Because of the deterministic approach taken in the mentioned research, the coupling current analysis and CEFM model can be applied to the specific problem of SCC in aluminum alloy 5083 (the alloy of interest for this dissertation that is highly sought after today because of its corrosion resistance and high strength to weight ratio). This dissertation research is specifically devoted to the experimental verification of the coupling current, which results from a coupling between the crack's internal and external environments, by spatially resolving them using the scanning vibrating probe (SVP) as a tool. Hence, through the use of a unique fracture mechanics setup, simultaneous mechanical and local electrochemical data may be obtained, in situ..

  13. Development of Multiple-Element Flame Emission Spectrometer Using CCD Detection

    ERIC Educational Resources Information Center

    Seney, Caryn S.; Sinclair, Karen V.; Bright, Robin M.; Momoh, Paul O.; Bozeman, Amelia D.

    2005-01-01

    The full wavelength coverage of charge coupled device (CCD) detector when coupled with an echelle spectrography, the system allows for simultaneously multiple element spectroscopy to be performed. The multiple-element flame spectrometer was built and characterized through the analysis of environmentally significant elements such as Ca, K, Na, Cu,…

  14. The Nature of Coupling with Intercollegiate Athletic Departments: Undergraduate Athletic Training Education Program Directors' Perceptions

    ERIC Educational Resources Information Center

    Roiger, Trevor C.; Card, Karen A.

    2012-01-01

    Context: Coupling theory, based on a tight-loose continuum, describes the nature of a connection, relationship, or interaction between entities. Understanding the nature of an ATEP's relationship with intercollegiate athletic departments is important to their growth and responsiveness to environmental change. Objective: To determine program…

  15. Sloshing of Cryogenic Helium Driven by Lateral Impulse/Gravity Gradient-Dominated/or g-Jitter-Dominated Accelerations and Orbital Dynamics

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Long, Y. T.; Zu, G. J.

    1996-01-01

    The coupling of slosh dynamics within a partially filled rotating dewar of superfluid helium 11 with spacecraft orbital dynamics is investigated in response to the environmental disturbances of (a) lateral impulses, (b) gravity gradients and (c) g-jitter forces. The purpose of this study is to investigate how the coupling of helium 11 fluid slosh dynamics driven by three cases of environmental force with spacecraft dynamics can affect the bubble deformations and their associated fluid and spacecraft mass centre fluctuations. The numerical computation of slosh dynamics is based on a rotational frame, while the spacecraft dynamics is associated with a non-rotational frame. Results show that the major contribution of orbital dynamics is driven by coupling with slosh dynamics. Neglecting the effect of slosh dynamics acting on the spacecraft may lead to the wrong results for the development of orbital and attitude control techniques.

  16. NUMERICAL MODELS AS ENABLING TOOLS FOR TIDAL-STREAM ENERGY EXTRACTION AND ENVIRONMENTAL IMPACT ASSESSMENT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Zhaoqing; Wang, Taiping

    This paper presents a modeling study conducted to evaluate tidal-stream energy extraction and its associated potential environmental impacts using a three-dimensional unstructured-grid coastal ocean model, which was coupled with a water-quality model and a tidal-turbine module.

  17. Phase shifting two coupled circadian pacemakers - Implications for jet lag

    NASA Technical Reports Server (NTRS)

    Gander, P. H.; Kronauer, R. E.; Graeber, R. C.

    1985-01-01

    Two Van der Pol oscillators with reciprocal linear velocity coupling are utilized to model the response of the human circadian timing system to abrupt displacements of the environmental time cues (zeitgebers). The core temperature rhythm and sleep-wake cycle simulated by the model are examined. The relationship between the masking of circadian rhythms by environmental variables and behavioral and physiological events and the rates of resynchronization is studied. The effects of zeitgeber phase shifts and zeitgeber strength on the resynchronization rates are analyzed. The influence of intrinsic pacemakers periods and coupling strength on resynchronization are investigated. The simulated data reveal that: resynchronization after a time zone shift depends on the magnitude of the shift; the time of day of the shift has little influence on resynchronization; the strength of zeitgebers affects the rate and direction of the resynchronization; the intrinsic pacemaker periods have a significant effect on resynchronization; and increasing the coupling between the oscillators results in an increase in the rate of resynchronization. The model data are compared to transmeridian flight studies data and similar resynchronization patterns are observed.

  18. [Construction and application of economy-pollution-environment three-dimensional evaluation model for district].

    PubMed

    Fan, Xin-Gang; Mi, Wen-Bao; Ma, Zhen-Ning

    2015-02-01

    For deep analysis on the regional environmental economic system, the paper analyzes the mutual relation of regional economy development, environmental quality, environmental pollution, and builds the theoretical basis. Then, the economy-pollution-environment quality three-dimensional coupling evaluation model for district is constructed. It includes economic development level index, environmental pollution index, and environmental quality index. The model is a cube, which has spatialization and visualization characteristics. The model includes 8 sub cubes, which expresses 8 types of state, e. g. low pollution-inferior quality-low level of economic development etc. The model can be used to evaluate the status of region, divide development phase, analyze evolution trend etc. It has two ways including relative meaning evaluation (RME) and absolute meaning evaluation (AME). Based on the model, Yinchuan City in the Ningxia Hui Autonomous Region is used as an example for the empirical study. Using RME, compared with Guangzhou city, The result shows that the Yinchuan City has been a high pollution-low quality-low level of economic development state for a long period during 1996-2010. After 2007, the state changed to a high pollution-high quality-low level of economic development. Now, the environmental quality of Yinchuan city gets better, but pollutant discharge pressure is high, and tends to be the break point of high environment quality and low environment. With AME, using national standard, the Yinchuan City remains a high pollution-low quality-low level of economic development state during 1996-2010. Empirical research verifies that different target reference areas and relevant national standards have different main parameters, the evaluating result has an flexible range. The dimensionless data enhances the coupling of index. The data position in model increases the visibility to the environmental management decisions. The model improves mismatches of calculated data size, time asymmetry of spatial data, verification of the former multi-target coupling model.

  19. How to make a tree ring: Coupling stem water flow and cambial activity in mature Alpine conifers

    NASA Astrophysics Data System (ADS)

    Peters, Richard L.; Frank, David C.; Treydte, Kerstin; Steppe, Kathy; Kahmen, Ansgar; Fonti, Patrick

    2017-04-01

    Inter-annual tree-ring measurements are used to understand tree-growth responses to climatic variability and reconstruct past climate conditions. In parallel, mechanistic models use experimentally defined plant-atmosphere interactions to explain past growth responses and predict future environmental impact on forest productivity. Yet, substantial inconsistencies within mechanistic model ensembles and mismatches with empirical data indicate that significant progress is still needed to understand the processes occurring at an intra-annual resolution that drive annual growth. However, challenges arise due to i) few datasets describing climatic responses of high-resolution physiological processes over longer time-scales, ii) uncertainties on the main mechanistic process limiting radial stem growth and iii) complex interactions between multiple environmental factors which obscure detection of the main stem growth driver, generating a gap between our understanding of intra- and inter-annual growth mechanisms. We attempt to bridge the gap between inter-annual tree-ring width and sub-daily radial stem-growth and provide a mechanistic perspective on how environmental conditions affect physiological processes that shape tree rings in conifers. We combine sub-hourly sap flow and point dendrometer measurements performed on mature Alpine conifers (Larix decidua) into an individual-based mechanistic tree-growth model to simulate sub-hourly cambial activity. The monitored trees are located along a high elevational transect in the Swiss Alps (Lötschental) to analyse the effect of increasing temperature. The model quantifies internal tree hydraulic pathways that regulate the turgidity within the cambial zone and induce cell enlargement for radial growth. The simulations are validated against intra-annual growth patterns derived from xylogenesis data and anatomical analyses. Our efforts advance the process-based understanding of how climate shapes the annual tree-ring structures and could potentially improve our ability to reconstruct the climate of the past and predict future growth under changing climate.

  20. A concise guide for the determination of less-studied technology-critical elements (Nb, Ta, Ga, In, Ge, Te) by inductively coupled plasma mass spectrometry in environmental samples

    NASA Astrophysics Data System (ADS)

    Filella, Montserrat; Rodushkin, Ilia

    2018-03-01

    There is an increasing demand for analytical techniques able to measure so-called 'technology-critical elements', a set of chemical elements increasingly used in technological applications, in environmental matrices. Nowadays, inductively coupled plasma-mass spectrometry (ICP-MS) has become the technique of choice for measuring trace element concentrations. However, its application is often less straightforward than often assumed. The hints and drawbacks of ICP-MS application to the measurement of a set of less-studied technology-critical elements (Nb, Ta, Ga, In, Ge and Te) is discussed here and concise guidelines given.

  1. Post-transcriptional modifications in development and stem cells.

    PubMed

    Frye, Michaela; Blanco, Sandra

    2016-11-01

    Cells adapt to their environment by linking external stimuli to an intricate network of transcriptional, post-transcriptional and translational processes. Among these, mechanisms that couple environmental cues to the regulation of protein translation are not well understood. Chemical modifications of RNA allow rapid cellular responses to external stimuli by modulating a wide range of fundamental biochemical properties and processes, including the stability, splicing and translation of messenger RNA. In this Review, we focus on the occurrence of N 6 -methyladenosine (m 6 A), 5-methylcytosine (m 5 C) and pseudouridine (Ψ) in RNA, and describe how these RNA modifications are implicated in regulating pluripotency, stem cell self-renewal and fate specification. Both post-transcriptional modifications and the enzymes that catalyse them modulate stem cell differentiation pathways and are essential for normal development. © 2016. Published by The Company of Biologists Ltd.

  2. Recent Development in Optical Chemical Sensors Coupling with Flow Injection Analysis

    PubMed Central

    Ojeda, Catalina Bosch; Rojas, Fuensanta Sánchez

    2006-01-01

    Optical techniques for chemical analysis are well established and sensors based on these techniques are now attracting considerable attention because of their importance in applications such as environmental monitoring, biomedical sensing, and industrial process control. On the other hand, flow injection analysis (FIA) is advisable for the rapid analysis of microliter volume samples and can be interfaced directly to the chemical process. The FIA has become a widespread automatic analytical method for more reasons; mainly due to the simplicity and low cost of the setups, their versatility, and ease of assembling. In this paper, an overview of flow injection determinations by using optical chemical sensors is provided, and instrumentation, sensor design, and applications are discussed. This work summarizes the most relevant manuscripts from 1980 to date referred to analysis using optical chemical sensors in FIA.

  3. Nanoscale Engineering of Designer Cellulosomes.

    PubMed

    Gunnoo, Melissabye; Cazade, Pierre-André; Galera-Prat, Albert; Nash, Michael A; Czjzek, Mirjam; Cieplak, Marek; Alvarez, Beatriz; Aguilar, Marina; Karpol, Alon; Gaub, Hermann; Carrión-Vázquez, Mariano; Bayer, Edward A; Thompson, Damien

    2016-07-01

    Biocatalysts showcase the upper limit obtainable for high-speed molecular processing and transformation. Efforts to engineer functionality in synthetic nanostructured materials are guided by the increasing knowledge of evolving architectures, which enable controlled molecular motion and precise molecular recognition. The cellulosome is a biological nanomachine, which, as a fundamental component of the plant-digestion machinery from bacterial cells, has a key potential role in the successful development of environmentally-friendly processes to produce biofuels and fine chemicals from the breakdown of biomass waste. Here, the progress toward so-called "designer cellulosomes", which provide an elegant alternative to enzyme cocktails for lignocellulose breakdown, is reviewed. Particular attention is paid to rational design via computational modeling coupled with nanoscale characterization and engineering tools. Remaining challenges and potential routes to industrial application are put forward. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Ask the experts: the challenges and benefits of flow chemistry to optimize drug development.

    PubMed

    Anderson, Neal; Gernaey, Krist V; Jamison, Timothy F; Kircher, Manfred; Wiles, Charlotte; Leadbeater, Nicholas E; Sandford, Graham; Richardson, Paul

    2012-09-01

    Against a backdrop of a struggling economic and regulatory climate, pharmaceutical companies have recently been forced to develop new ways to provide more efficient technology to meet the demands of a competitive drug industry. This issue, coupled with an increase in patent legislation and a rising generics market, makes these themes common issues in the growth of drug development. As a consequence, the importance of process chemistry and scale-up has never been more under the spotlight. Future Medicinal Chemistry wishes to share the thoughts and opinions of a variety of experts from this field, discussing issues concerning the use of flow chemistry to optimize drug development, the potential regulatory and environmental challenges faced with this, and whether the academic and industrial sectors could benefit from a more harmonized system relevant to process chemistry.

  5. Rubbery computing

    NASA Astrophysics Data System (ADS)

    Wilson, Katherine E.; Henke, E.-F. Markus; Slipher, Geoffrey A.; Anderson, Iain A.

    2017-04-01

    Electromechanically coupled dielectric elastomer actuators (DEAs) and dielectric elastomer switches (DESs) may form digital logic circuitry made entirely of soft and flexible materials. The expansion in planar area of a DEA exerts force across a DES, which is a soft electrode with strain-dependent resistivity. When compressed, the DES drops steeply in resistance and changes state from non-conducting to conducting. Logic operators may be achieved with different arrangements of interacting DE actuators and switches. We demonstrate combinatorial logic elements, including the fundamental Boolean logic gates, as well as sequential logic elements, including latches and flip-flops. With both data storage and signal processing abilities, the necessary calculating components of a soft computer are available. A noteworthy advantage of a soft computer with mechanosensitive DESs is the potential for responding to environmental strains while locally processing information and generating a reaction, like a muscle reflex.

  6. Emotional Stroop interference for threatening words is related to reduced EEG δ-β coupling and low attentional control.

    PubMed

    Putman, Peter; Arias-Garcia, Elsa; Pantazi, Ioanna; van Schie, Charlotte

    2012-05-01

    Previously, electroencephalographic (EEG) delta-beta coupling (positive correlation between power in the fast beta and slow delta frequency bands) has been related to affective processing. For instance, differences in delta-beta coupling have been observed between people in a psychological stress condition and controls. We previously reported relationships between attentional threat processing and delta-beta coupling and individual differences in attentional control. The present study extended and replicated these findings in a large mixed gender sample (N=80). Results demonstrated that emotional Stroop task interference for threatening words was related to self-reported attentional inhibition capacity and frontal delta-beta coupling. There was no clear gender difference for delta-beta coupling (only a non-significant trend) and the relationship between delta-beta coupling and attentional threat-processing was not affected by gender. These results replicate and extend an earlier finding concerning delta-beta coupling and cognitive affect regulation and further clarify relationships between delta-beta coupling, attentional control, and threat-processing. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. How low does iron go? Chasing the active species in fe-catalyzed cross-coupling reactions.

    PubMed

    Bedford, Robin B

    2015-05-19

    The catalytic cross-coupling reactions of organic halides or related substrates with organometallic nucleophiles form the cornerstone of many carbon-carbon bond-forming processes. While palladium-based catalysts typically mediate such reactions, there are increasing concerns about the long-term sustainability of palladium in synthesis. This is due to the high cost of palladium, coupled with its low natural abundance, environmentally deleterious extraction (∼6 g of metal are produced per ton of ore), toxicity, and competition for its use from the automotive and consumer electronics sectors. Therefore, there is a growing interest in replacing palladium-based catalysts with those incorporating more earth-abundant elements. With its low cost, high natural abundance, and low toxicity, iron makes a particularly appealing alternative, and accordingly, the development of iron-catalyzed cross-coupling is undergoing explosive growth. However, our understanding of the mechanisms that underpin the iron-based catalytic cycles is still very much in its infancy. Mechanistic insight into catalytic reactions is not only academically important but also allows us to maximize the efficiency of processes or even to develop entirely new transformations. Key to the development of robust mechanistic models for cross-coupling is knowing the lowest oxidation state in the cycle. Once this is established, we can explore subsequent redox processes and build the catalytic manifold. Until we know with confidence what the lowest oxidation state is, any cycles proposed are largely just guesswork. To date, Fe(-II), Fe(-I), Fe(0), Fe(I), and Fe(II) have been proposed as contenders for the lowest-oxidation-state species in the cycle in iron-catalyzed cross-coupling; the aim of this Account is to pull together the various pieces of evidence in support, or otherwise, of each of these suggestions in turn. There currently exists no direct evidence that oxidation states below Fe(0) are active in the catalytic cycle. Meanwhile, the reactivity required of the lowest-oxidation-state species has been observed with model compounds in higher oxidation states, implying that there is no need to invoke such low oxidation states. While subzero-valent complexes do indeed act as effective precatalysts, it is important to recognize that this tells us that they are efficiently converted to an active catalyst but says nothing about the oxidation states of the species in the catalytic cycle. Zero-valent heterogeneous iron nanoparticles can be formed under typical catalytic conditions, but there is no evidence to suggest that homogeneous Fe(0) complexes can be produced under comparable conditions. It seems likely that the zero-valent nanoparticles act as a reservoir for soluble higher-oxidation-state species. Fe(II) complexes can certainly be formed under catalytically relevant conditions, and when bulky nucleophilic coupling partners are exploited, potential intermediates can be isolated. However, the bulky reagents act as poor proxies for most nucleophiles used in cross-coupling, as they give Fe(II) organometallic intermediates that are kinetically stabilized with respect to reductive elimination. When more realistic substrates are exploited, reduction or disproportionation to Fe(I) is widely observed, and while it still has not been conclusively proved, this oxidation state currently represents a likely candidate for the lowest one active in many iron-catalyzed cross-coupling processes.

  8. The Challenges to Coupling Dynamic Geospatial Models

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goldstein, N

    2006-06-23

    Many applications of modeling spatial dynamic systems focus on a single system and a single process, ignoring the geographic and systemic context of the processes being modeled. A solution to this problem is the coupled modeling of spatial dynamic systems. Coupled modeling is challenging for both technical reasons, as well as conceptual reasons. This paper explores the benefits and challenges to coupling or linking spatial dynamic models, from loose coupling, where information transfer between models is done by hand, to tight coupling, where two (or more) models are merged as one. To illustrate the challenges, a coupled model of Urbanizationmore » and Wildfire Risk is presented. This model, called Vesta, was applied to the Santa Barbara, California region (using real geospatial data), where Urbanization and Wildfires occur and recur, respectively. The preliminary results of the model coupling illustrate that coupled modeling can lead to insight into the consequences of processes acting on their own.« less

  9. Teaching Biology Field Courses in the Wake of Environmental Disasters.

    ERIC Educational Resources Information Center

    Baca, Bart J.

    1982-01-01

    A biology field course organized to study the effects of the June 1979 Mexican oil spill on the marine biology of the shores of south Texas and Mexico is described, demonstrating how to effectively couple a biology classroom course with a natural or human caused environmental disaster. (Author/DC)

  10. The Urban Tree Project

    ERIC Educational Resources Information Center

    Barnett, Michael; Houle, Meredith; Hufnagel, Elizabeth; Pancic, Alexander; Lehman, Mike; Hoffman, Emily

    2010-01-01

    Geospatial technologies have emerged over the last 15 years as one of the key tools used by environmental scientists (NRC 2006). In fact, educators have recognized that coupling geospatial technologies with environmental science topics and scientific data sets opens the door to local and regional scientific investigations (McInerney 2006). In this…

  11. Post-acquisition data processing for the screening of transformation products of different organic contaminants. Two-year monitoring of river water using LC-ESI-QTOF-MS and GCxGC-EI-TOF-MS.

    PubMed

    López, S Herrera; Ulaszewska, M M; Hernando, M D; Martínez Bueno, M J; Gómez, M J; Fernández-Alba, A R

    2014-11-01

    This study describes a comprehensive strategy for detecting and elucidating the chemical structures of expected and unexpected transformation products (TPs) from chemicals found in river water and effluent wastewater samples, using liquid chromatography coupled to electrospray ionization quadrupole-time-of-flight mass spectrometer (LC-ESI-QTOF-MS), with post-acquisition data processing and an automated search using an in-house database. The efficacy of the mass defect filtering (MDF) approach to screen metabolites from common biotransformation pathways was tested, and it was shown to be sufficiently sensitive and applicable for detecting metabolites in environmental samples. Four omeprazole metabolites and two venlafaxine metabolites were identified in river water samples. This paper reports the analytical results obtained during 2 years of monitoring, carried out at eight sampling points along the Henares River (Spain). Multiresidue monitoring, for targeted analysis, includes a group of 122 chemicals, amongst which are pharmaceuticals, personal care products, pesticides and PAHs. For this purpose, two analytical methods were used based on direct injection with a LC-ESI-QTOF-MS system and stir bar sorptive extraction (SBSE) with bi-dimensional gas chromatography coupled with a time-of-flight spectrometer (GCxGC-EI-TOF-MS).

  12. [Landscape structure and ecological coupling analysis of ecotone on the west Sonnen Plain].

    PubMed

    Song, Changchun; Deng, Wei; Song, Xinshan

    2003-09-01

    Ecotone is a special zone in the landscape, which is very susceptive to the changes in environmental conditions, and hence, is prone to the disturbance by unfavorable conditions. Human activity has a series of positive and negative effects on it, and greatly changes the geo-chemical process in the ecosystem. In the ecosystem, especially in the ecotone, different systems and regimes are interconnected and inter-determined. For the sustainable development of ecosystem and the protection and rational utilization of resources, it is of great importance to study this internal relationship and to seek rational regulation and control measures. With the ecotone in the west Songnen Plain as an example, and based on the studies of the topography, physiognomy, soil, vegetation, and their geographic distribution in the ecotone., this paper explained the structure of the ecological landscape, and quantitatively analyzed the ecological geo-chemical processes under different landscape conditions. In addition, this paper also tried to make coupling analyses to the ecologic succession and the landscape geo-chemical environment. Under current conditions, the succession of plant communities and the shift of soil landscape geo-chemical conditions in the west Songnen Plain are almost co-instantaneous, and these two factors can inter-determined under certain conditions.

  13. Preface to the Special Issue on TOUGH Symposium 2015

    NASA Astrophysics Data System (ADS)

    Blanco-Martín, Laura

    2017-11-01

    The TOUGH Symposium 2015 was held in Berkeley, California, September 28-30, 2015. The TOUGH family of codes, developed at the Energy Geosciences Division of Lawrence Berkeley National Laboratory (LBNL), is a suite of computer programs for the simulation of multiphase and multicomponent fluid and heat flows in porous and fractured media with applications in many geosciences fields, such as geothermal reservoir engineering, nuclear waste disposal, geological carbon sequestration, oil and gas reservoirs, gas hydrate research, vadose zone hydrology and environmental remediation. Since the first release in the 1980s, many modifications and enhancements have been continuously made to TOUGH and its various descendants (iTOUGH2, TOUGH+, TOUGH-MP, TOUGHREACT, TOUGH+HYDRATE, TMVOC...), at LBNL and elsewhere. Today, these codes are used worldwide in academia, government organizations and private companies in problems involving coupled hydrological, thermal, biogeochemical and geomechanical processes. The Symposia, organized every 2-3 years, bring together developers and users for an open exchange on recent code enhancements and applications. In 2015, the Symposium was attended by one hundred participants, representing thirty-four nationalities. This Special Issue in Computers & Geosciences gathers extended versions of selected Symposium proceedings related to (i) recent enhancements to the TOUGH family of codes and (ii) coupled flow and geomechanics processes modeling.

  14. Coupling Processes between Atmospheric Chemistry and Climate

    NASA Technical Reports Server (NTRS)

    Ko, Malcolm K. W.; Weisenstein, Debra K.; Shia, Run-Lie; Scott, Courtney J.; Sze, Nien Dak

    1998-01-01

    This is the fourth semi-annual report for NAS5-97039, covering the time period July through December 1998. The overall objective of this project is to improve the understanding of coupling processes between atmospheric chemistry and climate. Model predictions of the future distributions of trace gases in the atmosphere constitute an important component of the input necessary for quantitative assessments of global change. We will concentrate on the changes in ozone and stratospheric sulfate aerosol, with emphasis on how ozone in the lower stratosphere would respond to natural or anthropogenic changes. The key modeling tools for this work are the Atmospheric and Environmental Research (AER) two-dimensional chemistry-transport model, the AER two-dimensional stratospheric sulfate model, and the AER three-wave interactive model with full chemistry. For this six month period, we report on a modeling study of new rate constant which modify the NOx/NOy ratio in the lower stratosphere; sensitivity to changes in stratospheric water vapor in the future atmosphere; a study of N2O and CH4 observations which has allowed us to adjust diffusion in the 2-D CTM in order to obtain appropriate polar vortex isolation; a study of SF6 and age of air with comparisons of models and measurements; and a report on the Models and Measurements II effort.

  15. Quality-assurance results for routine water analyses in U.S. Geological Survey laboratories, water year 1998

    USGS Publications Warehouse

    Ludtke, Amy S.; Woodworth, Mark T.; Marsh, Philip S.

    2000-01-01

    The U.S. Geological Survey operates a quality-assurance program based on the analyses of reference samples for two laboratories: the National Water Quality Laboratory and the Quality of Water Service Unit. Reference samples that contain selected inorganic, nutrient, and low-level constituents are prepared and submitted to the laboratory as disguised routine samples. The program goal is to estimate precision and bias for as many analytical methods offered by the participating laboratories as possible. Blind reference samples typically are submitted at a rate of 2 to 5 percent of the annual environmental-sample load for each constituent. The samples are distributed to the laboratories throughout the year. The reference samples are subject to the identical laboratory handling, processing, and analytical procedures as those applied to environmental samples and, therefore, have been used as an independent source to verify bias and precision of laboratory analytical methods and ambient water-quality measurements. The results are stored permanently in the National Water Information System and the Blind Sample Project's data base. During water year 1998, 95 analytical procedures were evaluated at the National Water Quality Laboratory and 63 analytical procedures were evaluated at the Quality of Water Service Unit. An overall evaluation of the inorganic and low-level constituent data for water year 1998 indicated 77 of 78 analytical procedures at the National Water Quality Laboratory met the criteria for precision. Silver (dissolved, inductively coupled plasma-mass spectrometry) was determined to be imprecise. Five of 78 analytical procedures showed bias throughout the range of reference samples: chromium (dissolved, inductively coupled plasma-atomic emission spectrometry), dissolved solids (dissolved, gravimetric), lithium (dissolved, inductively coupled plasma-atomic emission spectrometry), silver (dissolved, inductively coupled plasma-mass spectrometry), and zinc (dissolved, inductively coupled plasma-mass spectrometry). At the National Water Quality Laboratory during water year 1998, lack of precision was indicated for 2 of 17 nutrient procedures: ammonia as nitrogen (dissolved, colorimetric) and orthophosphate as phosphorus (dissolved, colorimetric). Bias was indicated throughout the reference sample range for ammonia as nitrogen (dissolved, colorimetric, low level) and nitrate plus nitrite as nitrogen (dissolved, colorimetric, low level). All analytical procedures tested at the Quality of Water Service Unit during water year 1998 met the criteria for precision. One of the 63 analytical procedures indicated a bias throughout the range of reference samples: aluminum (whole-water recoverable, inductively coupled plasma-atomic emission spectrometry, trace).

  16. Advanced low carbon-to-nitrogen ratio wastewater treatment by electrochemical and biological coupling process.

    PubMed

    Deng, Shihai; Li, Desheng; Yang, Xue; Zhu, Shanbin; Xing, Wei

    2016-03-01

    Nitrogen pollution in ground and surface water significantly affects the environment and its organisms, thereby leading to an increasingly serious environmental problem. Such pollution is difficult to degrade because of the lack of carbon sources. Therefore, an electrochemical and biological coupling process (EBCP) was developed with a composite catalytic biological carrier (CCBC) and applied in a pilot-scale cylindrical reactor to treat wastewater with a carbon-to-nitrogen (C/N) ratio of 2. The startup process, coupling principle, and dynamic feature of the EBCP were examined along with the effects of hydraulic retention time (HRT), dissolved oxygen (DO), and initial pH on nitrogen removal. A stable coupling system was obtained after 51 days when plenty of biofilms were cultivated on the CCBC without inoculation sludge. Autotrophic denitrification, with [Fe(2+)] and [H] produced by iron-carbon galvanic cells in CCBC as electron donors, was confirmed by equity calculation of CODCr and nitrogen removal. Nitrogen removal efficiency was significantly influenced by HRT, DO, and initial pH with optimal values of 3.5 h, 3.5 ± 0.1 mg L(-1), and 7.5 ± 0.1, respectively. The ammonia, nitrate, and total nitrogen (TN) removal efficiencies of 90.1 to 95.3 %, 90.5 to 99.0 %, and 90.3 to 96.5 % were maintained with corresponding initial concentrations of 40 ± 2 mg L(-1) (NH3-N load of 0.27 ± 0.01 kg NH3-N m(-3) d(-1)), 20 ± 1 mg L(-1), and 60 ± 2 mg L(-1) (TN load of 0.41 ± 0.02 kg TN m(-3) d(-1)). Based on the Eckenfelder model, the kinetics equation of the nitrogen transformation along the reactor was N e  = N 0 exp (-0.04368 h/L(1.8438)). Hence, EBCP is a viable method for advanced low C/N ratio wastewater treatment.

  17. Evaluation of Hydrodynamic Chromatography Coupled with UV-Visible, Fluorescence and Inductively Coupled Plasma Mass Spectrometry Detectors for Sizing and Quantifying Colloids in Environmental Media

    PubMed Central

    Philippe, Allan; Schaumann, Gabriele E.

    2014-01-01

    In this study, we evaluated hydrodynamic chromatography (HDC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) for the analysis of nanoparticles in environmental samples. Using two commercially available columns (Polymer Labs-PDSA type 1 and 2), a set of well characterised calibrants and a new external time marking method, we showed that flow rate and eluent composition have few influence on the size resolution and, therefore, can be adapted to the sample particularity. Monitoring the agglomeration of polystyrene nanoparticles over time succeeded without observable disagglomeration suggesting that even weak agglomerates can be measured using HDC. Simultaneous determination of gold colloid concentration and size using ICP-MS detection was validated for elemental concentrations in the ppb range. HDC-ICP-MS was successfully applied to samples containing a high organic and ionic background. Indeed, online combination of UV-visible, fluorescence and ICP-MS detectors allowed distinguishing between organic molecules and inorganic colloids during the analysis of Ag nanoparticles in synthetic surface waters and TiO2 and ZnO nanoparticles in commercial sunscreens. Taken together, our results demonstrate that HDC-ICP-MS is a flexible, sensitive and reliable method to measure the size and the concentration of inorganic colloids in complex media and suggest that there may be a promising future for the application of HDC in environmental science. Nonetheless the rigorous measurements of agglomerates and of matrices containing natural colloids still need to be studied in detail. PMID:24587393

  18. Evaluation of hydrodynamic chromatography coupled with UV-visible, fluorescence and inductively coupled plasma mass spectrometry detectors for sizing and quantifying colloids in environmental media.

    PubMed

    Philippe, Allan; Schaumann, Gabriele E

    2014-01-01

    In this study, we evaluated hydrodynamic chromatography (HDC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) for the analysis of nanoparticles in environmental samples. Using two commercially available columns (Polymer Labs-PDSA type 1 and 2), a set of well characterised calibrants and a new external time marking method, we showed that flow rate and eluent composition have few influence on the size resolution and, therefore, can be adapted to the sample particularity. Monitoring the agglomeration of polystyrene nanoparticles over time succeeded without observable disagglomeration suggesting that even weak agglomerates can be measured using HDC. Simultaneous determination of gold colloid concentration and size using ICP-MS detection was validated for elemental concentrations in the ppb range. HDC-ICP-MS was successfully applied to samples containing a high organic and ionic background. Indeed, online combination of UV-visible, fluorescence and ICP-MS detectors allowed distinguishing between organic molecules and inorganic colloids during the analysis of Ag nanoparticles in synthetic surface waters and TiO₂ and ZnO nanoparticles in commercial sunscreens. Taken together, our results demonstrate that HDC-ICP-MS is a flexible, sensitive and reliable method to measure the size and the concentration of inorganic colloids in complex media and suggest that there may be a promising future for the application of HDC in environmental science. Nonetheless the rigorous measurements of agglomerates and of matrices containing natural colloids still need to be studied in detail.

  19. Couple Consensus during Marital Joint Decision-Making: A Context, Process, Outcome Model.

    ERIC Educational Resources Information Center

    Godwin, Deborah D.; Scanzoni, John

    1989-01-01

    Tested conceptual model of context, processes, and outcomes of joint marital decision making of married couples (N=188) which specified spouses' process variables as individual-level measures and partners' consensus as a couple construct. Found context factor of spouses' emotional interdependence influenced both partners' coerciveness and degree…

  20. One multi-media environmental system with linkage between meteorology/ hydrology/ air quality models and water quality model

    NASA Astrophysics Data System (ADS)

    Tang, C.; Lynch, J. A.; Dennis, R. L.

    2016-12-01

    The biogeochemical processing of nitrogen and associated pollutants is driven by meteorological and hydrological processes in conjunction with pollutant loading. There are feedbacks between meteorology and hydrology that will be affected by land-use change and climate change. Changes in meteorology will affect pollutant deposition. It is important to account for those feedbacks and produce internally consistent simulations of meteorology, hydrology, and pollutant loading to drive the (watershed/water quality) biogeochemical models. In this study, the ecological response to emission reductions in streams in the Potomac watershed was evaluated. Firstly, we simulated the deposition by using the fully coupled Weather Research & Forecasting (WRF) model and the Community Multiscale Air Quality (CAMQ) model; secondly, we created the hydrological data by the offline linked Variable Infiltration Capacity (VIC) model and the WRF model. Lastly, we investigated the water quality by one comprehensive/environment model, namely the linkage of CMAQ, WRF, VIC and the Model of Acidification of Groundwater In Catchment (MAGIC) model from 2002 to 2010.The simulated results (such as NO3, SO4, and SBC) fit well to the observed values. The linkage provides a generally accurate, well-tested tool for evaluating sensitivities to varying meteorology and environmental changes on acidification and other biogeochemical processes, with capability to comprehensively explore strategic policy and management design.

  1. Combining HJ CCD, GF-1 WFV and MODIS Data to Generate Daily High Spatial Resolution Synthetic Data for Environmental Process Monitoring.

    PubMed

    Wu, Mingquan; Huang, Wenjiang; Niu, Zheng; Wang, Changyao

    2015-08-20

    The limitations of satellite data acquisition mean that there is a lack of satellite data with high spatial and temporal resolutions for environmental process monitoring. In this study, we address this problem by applying the Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model (ESTARFM) and the Spatial and Temporal Data Fusion Approach (STDFA) to combine Huanjing satellite charge coupled device (HJ CCD), Gaofen satellite no. 1 wide field of view camera (GF-1 WFV) and Moderate Resolution Imaging Spectroradiometer (MODIS) data to generate daily high spatial resolution synthetic data for land surface process monitoring. Actual HJ CCD and GF-1 WFV data were used to evaluate the precision of the synthetic images using the correlation analysis method. Our method was tested and validated for two study areas in Xinjiang Province, China. The results show that both the ESTARFM and STDFA can be applied to combine HJ CCD and MODIS reflectance data, and GF-1 WFV and MODIS reflectance data, to generate synthetic HJ CCD data and synthetic GF-1 WFV data that closely match actual data with correlation coefficients (r) greater than 0.8989 and 0.8643, respectively. Synthetic red- and near infrared (NIR)-band data generated by ESTARFM are more suitable for the calculation of Normalized Different Vegetation Index (NDVI) than the data generated by STDFA.

  2. Combining HJ CCD, GF-1 WFV and MODIS Data to Generate Daily High Spatial Resolution Synthetic Data for Environmental Process Monitoring

    PubMed Central

    Wu, Mingquan; Huang, Wenjiang; Niu, Zheng; Wang, Changyao

    2015-01-01

    The limitations of satellite data acquisition mean that there is a lack of satellite data with high spatial and temporal resolutions for environmental process monitoring. In this study, we address this problem by applying the Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model (ESTARFM) and the Spatial and Temporal Data Fusion Approach (STDFA) to combine Huanjing satellite charge coupled device (HJ CCD), Gaofen satellite no. 1 wide field of view camera (GF-1 WFV) and Moderate Resolution Imaging Spectroradiometer (MODIS) data to generate daily high spatial resolution synthetic data for land surface process monitoring. Actual HJ CCD and GF-1 WFV data were used to evaluate the precision of the synthetic images using the correlation analysis method. Our method was tested and validated for two study areas in Xinjiang Province, China. The results show that both the ESTARFM and STDFA can be applied to combine HJ CCD and MODIS reflectance data, and GF-1 WFV and MODIS reflectance data, to generate synthetic HJ CCD data and synthetic GF-1 WFV data that closely match actual data with correlation coefficients (r) greater than 0.8989 and 0.8643, respectively. Synthetic red- and near infrared (NIR)-band data generated by ESTARFM are more suitable for the calculation of Normalized Different Vegetation Index (NDVI) than the data generated by STDFA. PMID:26308017

  3. Environmental Collaborations Between Indigenous Communities and Western Science: Case Studies and Reflections

    NASA Astrophysics Data System (ADS)

    Emanuel, R. E.

    2016-12-01

    The study of coupled natural and human systems in a changing world can benefit greatly from indigenous perspectives, which have the potential to bring deep, placed-based understanding to complex environmental issues while promoting sustainable solutions to pressing socio-environmental problems. In recent years, scientists have begun to embrace indigenous knowledge and perspectives, but indigenous voices in the sciences remain relatively few. At the same time, indigenous communities face wide ranging and unique vulnerabilities to global environmental change on a variety of fronts, particularly where water resources are concerned. Given this situation, indigenous scientists often find themselves bridging both western scientific and indigenous communities, sometimes embodying the nexus in a literal sense. Here I reflect on this nexus from the perspective of an indigenous hydrologist collaborating with American Indian communities in North Carolina, which has the largest American Indian population of any state in the eastern US. Intertwining case studies of coupled natural and human systems illustrate some of the the challenges, complexities, and successes of ongoing collaborations with tribal communities and Native-serving organizations on water resource issues, environmental impacts of food and energy production, and broadening participation of American Indians in the sciences.

  4. Processing device with self-scrubbing logic

    DOEpatents

    Wojahn, Christopher K.

    2016-03-01

    An apparatus includes a processing unit including a configuration memory and self-scrubber logic coupled to read the configuration memory to detect compromised data stored in the configuration memory. The apparatus also includes a watchdog unit external to the processing unit and coupled to the self-scrubber logic to detect a failure in the self-scrubber logic. The watchdog unit is coupled to the processing unit to selectively reset the processing unit in response to detecting the failure in the self-scrubber logic. The apparatus also includes an external memory external to the processing unit and coupled to send configuration data to the configuration memory in response to a data feed signal outputted by the self-scrubber logic.

  5. Fueling industrial biotechnology growth with bioethanol.

    PubMed

    Otero, José Manuel; Panagiotou, Gianni; Olsson, Lisbeth

    2007-01-01

    Industrial biotechnology is the conversion of biomass via biocatalysis, microbial fermentation, or cell culture to produce chemicals, materials, and/or energy. Industrial biotechnology processes aim to be cost-competitive, environmentally favorable, and self-sustaining compared to their petrochemical equivalents. Common to all processes for the production of energy, commodity, added value, or fine chemicals is that raw materials comprise the most significant cost fraction, particularly as operating efficiencies increase through practice and improving technologies. Today, crude petroleum represents the dominant raw material for the energy and chemical sectors worldwide. Within the last 5 years petroleum prices, stability, and supply have increased, decreased, and been threatened, respectively, driving a renewed interest across academic, government, and corporate centers to utilize biomass as an alternative raw material. Specifically, bio-based ethanol as an alternative biofuel has emerged as the single largest biotechnology commodity, with close to 46 billion L produced worldwide in 2005. Bioethanol is a leading example of how systems biology tools have significantly enhanced metabolic engineering, inverse metabolic engineering, and protein and enzyme engineering strategies. This enhancement stems from method development for measurement, analysis, and data integration of functional genomics, including the transcriptome, proteome, metabolome, and fluxome. This review will show that future industrial biotechnology process development will benefit tremendously from the precedent set by bioethanol - that enabling technologies (e.g., systems biology tools) coupled with favorable economic and socio-political driving forces do yield profitable, sustainable, and environmentally responsible processes. Biofuel will continue to be the keystone of any industrial biotechnology-based economy whereby biorefineries leverage common raw materials and unit operations to integrate diverse processes to produce demand-driven product portfolios.

  6. Regional and climate forcing on forage fish and apex predators in the California Current: new insights from a fully coupled ecosystem model.

    NASA Astrophysics Data System (ADS)

    Fiechter, J.; Rose, K.; Curchitser, E. N.; Huckstadt, L. A.; Costa, D. P.; Hedstrom, K.

    2016-12-01

    A fully coupled ecosystem model is used to describe the impact of regional and climate variability on changes in abundance and distribution of forage fish and apex predators in the California Current Large Marine Ecosystem. The ecosystem model consists of a biogeochemical submodel (NEMURO) embedded in a regional ocean circulation submodel (ROMS), and both coupled with a multi-species individual-based submodel for two forage fish species (sardine and anchovy) and one apex predator (California sea lion). Sardine and anchovy are specifically included in the model as they exhibit significant interannual and decadal variability in population abundances, and are commonly found in the diet of California sea lions. Output from the model demonstrates how regional-scale (i.e., upwelling intensity) and basin-scale (i.e., PDO and ENSO signals) physical processes control species distributions and predator-prey interactions on interannual time scales. The results also illustrate how variability in environmental conditions leads to the formation of seasonal hotspots where prey and predator spatially overlap. While specifically focused on sardine, anchovy and sea lions, the modeling framework presented here can provide new insights into the physical and biological mechanisms controlling trophic interactions in the California Current, or other regions where similar end-to-end ecosystem models may be implemented.

  7. Effects of environmental change on groundwater recharge in the Desert Southwest

    USGS Publications Warehouse

    Phillips, Fred M.; Walvoord, Michelle Ann; Small, Eric E.; Hogan, James F.; Phillips, Fred M.; Scanlon, Bridget R.

    2004-01-01

    Climate and other environmental conditions have varied in the past, and will almost certainly vary significantly in the near future. The response of groundwater recharge to changes in environmental conditions is thus a matter of active concem for water-resources management. The major mechanisms for this response of recharge are three-fold. First, changes in vegetation communities can shift the water balance at the base of the root zone, increasing or decreasing the amount of recharge. Second, variations in the amount of runoff can affect channel recharge. Finally, shifts in the seasonality of precipitation can strongly affect the fraction that is evapotranspired back into the atmosphere and thus affect the amount that becomes recharge. Increases in recharge (defined as the water flux across the water table) may in some cases significantly increase fluxes through regional aquifers, but in other cases, depending on the hydrogeology, may only result in increased streamflow or evapotranspiration within the recharge area. Basins with relatively low maximum elevations, deep water tables, thin soils, and highly permeable recharge areas experience the largest recharge response to increases in precipitation. The relatively well-known paleoenvironmental history of the American Southwest can be compared with various lines of evidence for changes in recharge. These lines of evidence include timing of speleothem formation, chloride profiles in thick vadose zones, changes in water table shown by subsurface calcite precipitation, and expanded groundwater discharge areas. This evidence indicates that the wettest periods of the past 25 ka, which were generally between 20 and 13 ka, were also periods of enhanced vadose zone fluxes and aquifer discharge. Climate-driven changes in recharge appear to have been substantially mediated through changes in vegetation. This evidence for strong recharge response to past environmental changes indicates that expected future climate and environmental change will also cause changes in recharge. The ability to adequately predict future changes in recharge will depend on developing process-based numerical models that can simulate coupled climate/vegetation/ vadose zone processes and incorporate the outputs into groundwater/surface water models that can resolve processes at scales ranging from the hillslope to the basin. 

  8. Sensitivity of alpine watersheds to global change

    NASA Astrophysics Data System (ADS)

    Zierl, B.; Bugmann, H.

    2003-04-01

    Mountains provide society with a wide range of goods and services, so-called mountain ecosystem services. Besides many others, these services include the most precious element for life on earth: fresh water. Global change imposes significant environmental pressure on mountain watersheds. Climate change is predicted to modify water availability as well as shift its seasonality. In fact, the continued capacity of mountain regions to provide fresh water to society is threatened by the impact of environmental and social changes. We use RHESSys (Regional HydroEcological Simulation System) to analyse the impact of climate as well as land use change (e.g. afforestation or deforestation) on hydrological processes in mountain catchments using sophisticated climate and land use scenarios. RHESSys combines distributed flow modelling based on TOPMODEL with an ecophysiological canopy model based on BIOME-BGC and a climate interpolation scheme based on MTCLIM. It is a spatially distributed daily time step model designed to solve the coupled cycles of water, carbon, and nitrogen in mountain catchments. The model is applied to various mountain catchments in the alpine area. Dynamic hydrological and ecological properties such as river discharge, seasonality of discharge, peak flows, snow cover processes, soil moisture, and the feedback of a changing biosphere on hydrology are simulated under current as well as under changed environmental conditions. Results of these studies will be presented and discussed. This project is part of an over overarching EU-project called ATEAM (acronym for Advanced Terrestrial Ecosystem Analysis and Modelling) assessing the vulnerability of European ecosystem services.

  9. Environmental monitoring of the area surrounding oil wells in Val d'Agri (Italy): element accumulation in bovine and ovine organs.

    PubMed

    Miedico, Oto; Iammarino, Marco; Paglia, Giuseppe; Tarallo, Marina; Mangiacotti, Michele; Chiaravalle, A Eugenio

    2016-06-01

    In this work, environmental heavy metal contamination in the Val d'Agri area of Southern Italy was monitored, measuring the accumulation of 18 heavy metals (U, Hg, Pb, Cd, As, Sr, Sn, V, Ni, Cr, Mo, Co, Cu, Zn, Ca, Mn, Fe, and Al) in the organs of animals raised in the surrounding area (kidney, lung, and liver of bovine and ovine species). Val d'Agri features various oil processing centers which are potentially a significant source of environmental pollution, making it essential to perform studies that will outline the state of the art on which any recovery plans and interventions may be developed. The analysis was carried out using official and accredited analytical methods based on inductively coupled plasma mass spectrometry, and the measurements were statistically processed in order to give a contribution to risk assessment. Even though five samples showed Pb and Cd concentrations above the limits defined in the European Commission Regulation (EC) No 1881/2006, the mean concentrations of most elements suggest that contamination in this area is low. Consequently, these results also suggest that there is no particular risk for human exposure to toxic trace elements. Nevertheless, the findings of this work confirm that element accumulation in ovine species is correlated with geographical livestock area. Therefore, ovine-specific organs might be used as bioindicators for monitoring contamination by specific toxic elements in exposed areas.

  10. Microbiota Dynamics Associated with Environmental Conditions and Potential Roles of Cellulolytic Communities in Traditional Chinese Cereal Starter Solid-State Fermentation.

    PubMed

    Li, Pan; Liang, Hebin; Lin, Wei-Tie; Feng, Feng; Luo, Lixin

    2015-08-01

    Traditional Chinese solid-state fermented cereal starters contain highly complex microbial communities and enzymes. Very little is known, however, about the microbial dynamics related to environmental conditions, and cellulolytic communities have never been proposed to exist during cereal starter fermentation. In this study, we performed Illumina MiSeq sequencing combined with PCR-denaturing gradient gel electrophoresis to investigate microbiota, coupled with clone library construction to trace cellulolytic communities in both fermentation stages. A succession of microbial assemblages was observed during the fermentation of starters. Lactobacillales and Saccharomycetales dominated the initial stages, with a continuous decline in relative abundance. However, thermotolerant and drought-resistant Bacillales, Eurotiales, and Mucorales were considerably accelerated during the heating stages, and these organisms dominated until the end of fermentation. Enterobacteriales were consistently ubiquitous throughout the process. For the cellulolytic communities, only the genera Sanguibacter, Beutenbergia, Agrobacterium, and Erwinia dominated the initial fermentation stages. In contrast, stages at high incubation temperature induced the appearance and dominance of Bacillus, Aspergillus, and Mucor. The enzymatic dynamics of amylase and glucoamylase also showed a similar trend, with the activities clearly increased in the first 7 days and subsequently decreased until the end of fermentation. Furthermore, β-glucosidase activity continuously and significantly increased during the fermentation process. Evidently, cellulolytic potential can adapt to environmental conditions by changes in the community structure during the fermentation of starters. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  11. Decision-making process of prenatal screening described by pregnant women and their partners.

    PubMed

    Wätterbjörk, Inger; Blomberg, Karin; Nilsson, Kerstin; Sahlberg-Blom, Eva

    2015-10-01

    Pregnant women are often faced with having to decide about prenatal screening for Down's syndrome. However, the decision to participate in or refrain from prenatal screening can be seen as an important decision not only for the pregnant woman but also for both the partners. The aim of this study was to explore the couples' processes of decision making about prenatal screening. A total of 37 semi-structured interviews conducted at two time points were analysed using the interpretive description. The study was carried out in Maternal health-care centres, Örebro County Council, Sweden. Fifteen couples of different ages and with different experiences of pregnancy and childbirth were interviewed. Three different patterns of decision making were identified. For the couples in 'The open and communicative decision-making process', the process was straightforward and rational, and the couples discussed the decision with each other. 'The closed and personal decision-making process' showed an immediate and non-communicative decision making where the couples decided each for themselves. The couples showing 'The searching and communicative decision-making process' followed an arduous road in deciding whether to participate or not in prenatal screening and how to cope with the result. The decision-making process was for some couples a fairly straightforward decision, while for others it was a more complex process that required a great deal of consideration. © 2013 John Wiley & Sons Ltd.

  12. Linking the historical and chemical definitions of diabatic states for charge and excitation energy transfer reactions in condensed phase.

    PubMed

    Pavanello, Michele; Neugebauer, Johannes

    2011-10-07

    Marcus theory of electron transfer (ET) and Förster theory of excitation energy transfer (EET) rely on the Condon approximation and the theoretical availability of initial and final states of ET and EET reactions, often called diabatic states. Recently [Subotnik et al., J. Chem. Phys. 130, 234102 (2009)], diabatic states for practical calculations of ET and EET reactions were defined in terms of their interactions with the surrounding environment. However, from a purely theoretical standpoint, the definition of diabatic states must arise from the minimization of the dynamic couplings between the trial diabatic states. In this work, we show that if the Condon approximation is valid, then a minimization of the derived dynamic couplings leads to corresponding diabatic states for ET reactions taking place in solution by diagonalization of the dipole moment matrix, which is equivalent to a Boys localization algorithm; while for EET reactions in solution, diabatic states are found through the Edmiston-Ruedenberg localization algorithm. In the derivation, we find interesting expressions for the environmental contribution to the dynamic coupling of the adiabatic states in condensed-phase processes. In one of the cases considered, we find that such a contribution is trivially evaluable as a scalar product of the transition dipole moment with a quantity directly derivable from the geometry arrangement of the nuclei in the molecular environment. Possibly, this has applications in the evaluation of dynamic couplings for large scale simulations. © 2011 American Institute of Physics

  13. Identification of trace levels of selenomethionine and related organic selenium species in high-ionic-strength waters.

    PubMed

    LeBlanc, Kelly L; Ruzicka, Josef; Wallschläger, Dirk

    2016-02-01

    A new anion-exchange chromatographic separation method was used for the simultaneous speciation analysis of selenoamino acids and the more ubiquitous inorganic selenium oxyanions, selenite and selenate. For quantification, this separation was coupled to inductively coupled plasma-mass spectrometry to achieve an instrumental detection limit of 5 ng Se L(-1) for all species. This chromatographic method was also coupled to electrospray tandem mass spectrometry to observe the negative ion mode fragmentation of selenomethionine and one of its oxidation products. Low detection limits were achieved, which were similar to those obtained using inductively coupled plasma-mass spectrometry. An extensive preconcentration and cleanup procedure using cation-exchange solid-phase extraction was developed for the identification and quantification of trace levels of selenomethionine in environmental samples. Preconcentration factors of up to five were observed for selenomethionine, which in addition to the removal of high concentrations of sulphate and chloride from industrial process waters, allowed for an unambiguous analysis that would have been impossible otherwise. Following these methods, selenomethionine was identified at an original concentration of 3.2 ng Se L(-1) in samples of effluent collected at a coal-fired power plant's biological remediation site. It is the first time that this species has been identified in the environment, outside of a biological entity. Additionally, oxidation products of selenomethionine were identified in river water and laboratory algal culture samples. High-resolution mass spectrometry was employed to postulate the chemical structures of these species.

  14. Land and atmosphere interactions using satellite remote sensing and a coupled mesoscale/land surface model

    NASA Astrophysics Data System (ADS)

    Hong, Seungbum

    Land and atmosphere interactions have long been recognized for playing a key role in climate and weather modeling. However their quantification has been challenging due to the complex nature of the land surface amongst various other reasons. One of the difficult parts in the quantification is the effect of vegetation which are related to land surface processes such soil moisture variation and to atmospheric conditions such as radiation. This study addresses various relational investigations among vegetation properties such as Normalized Difference Vegetation Index (NDVI), Leaf Area Index (LAI), surface temperature (TSK), and vegetation water content (VegWC) derived from satellite sensors such as Moderate Resolution Imaging Spectroradiometer (MODIS) and EOS Advanced Microwave Scanning Radiometer (AMSR-E). The study provides general information about a physiological behavior of vegetation for various environmental conditions. Second, using a coupled mesoscale/land surface model, we examined the effects of vegetation and its relationship with soil moisture on the simulated land-atmospheric interactions through the model sensitivity tests. The Weather Research and Forecasting (WRF) model was selected for this study, and the Noah land surface model (Noah LSM) implemented in the WRF model was used for the model coupled system. This coupled model was tested through two parameterization methods for vegetation fraction using MODIS data and through model initialization of soil moisture from High Resolution Land Data Assimilation System (HRLDAS). Then, this study evaluates the model improvements for each simulation method.

  15. Space-based ornithology: studying bird migration and environmental change in North America

    NASA Astrophysics Data System (ADS)

    Smith, James A.; Deppe, Jill L.

    2008-10-01

    Natural fluctuations in the availability of critical stopover sites coupled with anthropogenic destruction of wetlands, land-use change, and anticipated losses due to climate change present migratory birds with a formidable challenge. Space based technology in concert with bird migration modeling and geographical information analysis yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At the NASA Goddard Space Flight Center, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. We use an individual-based bird biophysical migration model, driven by remotely sensed land surface data, climate and hydrologic data, and biological field observations to study migratory bird responses to environmental change in North America. Simulation allows us to study bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. We illustrate our approach by simulating the spring migration of pectoral sandpipers from the Gulf of Mexico to Alaska. Mean stopover length and trajectory patterns are consistent with field observations.

  16. Space-Based Ornithology - Studying Bird Migration and Environmental Change in North America

    NASA Technical Reports Server (NTRS)

    Smith, James A.; Deppe, Jill L.

    2008-01-01

    Natural fluctuations in the availability of critical stopover sites coupled with anthropogenic destruction of wetlands, land-use change, and anticipated losses due to climate change present migratory birds with a formidable challenge. Space based technology in concert with bird migration modeling and geographical information analysis yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At the NASA Goddard Space Flight Center, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. We use an individual-based bird biophysical migration model, driven by remotely sensed land surface data, climate and hydrologic data, and biological field observations to study migratory bird responses to environmental change in North America. Simulation allows us to study bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. We illustrate our approach by simulating the spring migration of pectoral sandpipers from the Gulf of Mexico to Alaska. Mean stopover length and trajectory patterns are consistent with field observations.

  17. Fast automated dual-syringe based dispersive liquid-liquid microextraction coupled with gas chromatography-mass spectrometry for the determination of polycyclic aromatic hydrocarbons in environmental water samples.

    PubMed

    Guo, Liang; Tan, Shufang; Li, Xiao; Lee, Hian Kee

    2016-03-18

    An automated procedure, combining low density solvent based solvent demulsification dispersive liquid-liquid microextraction (DLLME) with gas chromatography-mass spectrometry analysis, was developed for the determination of polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. Capitalizing on a two-rail commercial autosampler, fast solvent transfer using a large volume syringe dedicated to the DLLME process, and convenient extract collection using a small volume microsyringe for better GC performance were enabled. Extraction parameters including the type and volume of extraction solvent, the type and volume of dispersive solvent and demulsification solvent, extraction and demulsification time, and the speed of solvent injection were investigated and optimized. Under the optimized conditions, the linearity ranged from 0.1 to 50 μg/L, 0.2 to 50 μg/L, and 0.5 to 50 μg/L, depending on the analytes. Limits of detection were determined to be between 0.023 and 0.058 μg/L. The method was applied to determine PAHs in environmental water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Integrating Materials, Manufacturing, Design and Validation for Sustainability in Future Transport Systems

    NASA Astrophysics Data System (ADS)

    Price, M. A.; Murphy, A.; Butterfield, J.; McCool, R.; Fleck, R.

    2011-05-01

    The predictive methods currently used for material specification, component design and the development of manufacturing processes, need to evolve beyond the current `metal centric' state of the art, if advanced composites are to realise their potential in delivering sustainable transport solutions. There are however, significant technical challenges associated with this process. Deteriorating environmental, political, economic and social conditions across the globe have resulted in unprecedented pressures to improve the operational efficiency of the manufacturing sector generally and to change perceptions regarding the environmental credentials of transport systems in particular. There is a need to apply new technologies and develop new capabilities to ensure commercial sustainability in the face of twenty first century economic and climatic conditions as well as transport market demands. A major technology gap exists between design, analysis and manufacturing processes in both the OEMs, and the smaller companies that make up the SME based supply chain. As regulatory requirements align with environmental needs, manufacturers are increasingly responsible for the broader lifecycle aspects of vehicle performance. These include not only manufacture and supply but disposal and re-use or re-cycling. In order to make advances in the reduction of emissions coupled with improved economic efficiency through the provision of advanced lightweight vehicles, four key challenges are identified as follows: Material systems, Manufacturing systems, Integrated design methods using digital manufacturing tools and Validation systems. This paper presents a project which has been designed to address these four key issues, using at its core, a digital framework for the creation and management of key parameters related to the lifecycle performance of thermoplastic composite parts and structures. It aims to provide capability for the proposition, definition, evaluation and demonstration of advanced lightweight structures for new generation vehicles in the context of whole life performance parameters.

  19. Processes Affecting the Annual Surface Energy Budget at High-Latitude Terrestrial Sites

    NASA Astrophysics Data System (ADS)

    Persson, P. O. G.; Stone, R. S.; Grachev, A.; Matrosova, L.

    2012-04-01

    Instrumentation at four Study of Environmental Arctic Change (SEARCH) sites (Barrow, Eureka, Alert, and Tiksi) have been enhanced in the past 6 years, including during the 2007-2008 IPY. Data from these sites are used to investigate the annual cycle of the surface energy budget (SEB), its coupling to atmospheric processes, and for Alert, its interannual variability. The comprehensive data sets are useful for showing interactions between the atmosphere, surface, and soil at high temporal resolution throughout the annual cycle. Processes that govern the SEB variability at each site are identified, and their impacts on the SEB are quantified. For example, mesoscale modulation of the SEB caused by forcing from the local terrain (downslope wind events) and coastlines (sea and land breezes) are significant at Alert and Eureka, with these processes affecting both radiative, turbulent, and ground heat flux terms in the SEB. Sub-seasonal and interannual variations in atmospheric processes and SEB impact soil thermal structures, such as the depth and timing of the summer active layer. These analyses provide an improved understanding of the processes producing changes in surface and soil temperature, linking them through the SEB as affected by atmospheric processes.

  20. MJO simulation in CMIP5 climate models: MJO skill metrics and process-oriented diagnosis

    NASA Astrophysics Data System (ADS)

    Ahn, Min-Seop; Kim, Daehyun; Sperber, Kenneth R.; Kang, In-Sik; Maloney, Eric; Waliser, Duane; Hendon, Harry

    2017-12-01

    The Madden-Julian Oscillation (MJO) simulation diagnostics developed by MJO Working Group and the process-oriented MJO simulation diagnostics developed by MJO Task Force are applied to 37 Coupled Model Intercomparison Project phase 5 (CMIP5) models in order to assess model skill in representing amplitude, period, and coherent eastward propagation of the MJO, and to establish a link between MJO simulation skill and parameterized physical processes. Process-oriented diagnostics include the Relative Humidity Composite based on Precipitation (RHCP), Normalized Gross Moist Stability (NGMS), and the Greenhouse Enhancement Factor (GEF). Numerous scalar metrics are developed to quantify the results. Most CMIP5 models underestimate MJO amplitude, especially when outgoing longwave radiation (OLR) is used in the evaluation, and exhibit too fast phase speed while lacking coherence between eastward propagation of precipitation/convection and the wind field. The RHCP-metric, indicative of the sensitivity of simulated convection to low-level environmental moisture, and the NGMS-metric, indicative of the efficiency of a convective atmosphere for exporting moist static energy out of the column, show robust correlations with a large number of MJO skill metrics. The GEF-metric, indicative of the strength of the column-integrated longwave radiative heating due to cloud-radiation interaction, is also correlated with the MJO skill metrics, but shows relatively lower correlations compared to the RHCP- and NGMS-metrics. Our results suggest that modifications to processes associated with moisture-convection coupling and the gross moist stability might be the most fruitful for improving simulations of the MJO. Though the GEF-metric exhibits lower correlations with the MJO skill metrics, the longwave radiation feedback is highly relevant for simulating the weak precipitation anomaly regime that may be important for the establishment of shallow convection and the transition to deep convection.

  1. MJO simulation in CMIP5 climate models: MJO skill metrics and process-oriented diagnosis

    DOE PAGES

    Ahn, Min-Seop; Kim, Daehyun; Sperber, Kenneth R.; ...

    2017-03-23

    The Madden-Julian Oscillation (MJO) simulation diagnostics developed by MJO Working Group and the process-oriented MJO simulation diagnostics developed by MJO Task Force are applied to 37 Coupled Model Intercomparison Project phase 5 (CMIP5) models in order to assess model skill in representing amplitude, period, and coherent eastward propagation of the MJO, and to establish a link between MJO simulation skill and parameterized physical processes. Process-oriented diagnostics include the Relative Humidity Composite based on Precipitation (RHCP), Normalized Gross Moist Stability (NGMS), and the Greenhouse Enhancement Factor (GEF). Numerous scalar metrics are developed to quantify the results. Most CMIP5 models underestimate MJOmore » amplitude, especially when outgoing longwave radiation (OLR) is used in the evaluation, and exhibit too fast phase speed while lacking coherence between eastward propagation of precipitation/convection and the wind field. The RHCP-metric, indicative of the sensitivity of simulated convection to low-level environmental moisture, and the NGMS-metric, indicative of the efficiency of a convective atmosphere for exporting moist static energy out of the column, show robust correlations with a large number of MJO skill metrics. The GEF-metric, indicative of the strength of the column-integrated longwave radiative heating due to cloud-radiation interaction, is also correlated with the MJO skill metrics, but shows relatively lower correlations compared to the RHCP- and NGMS-metrics. Our results suggest that modifications to processes associated with moisture-convection coupling and the gross moist stability might be the most fruitful for improving simulations of the MJO. Though the GEF-metric exhibits lower correlations with the MJO skill metrics, the longwave radiation feedback is highly relevant for simulating the weak precipitation anomaly regime that may be important for the establishment of shallow convection and the transition to deep convection.« less

  2. Benthic ecology of tropical coastal lagoons: Environmental changes over the last decades in the Términos Lagoon, Mexico

    NASA Astrophysics Data System (ADS)

    Grenz, Christian; Fichez, Renaud; Silva, Carlos Álvarez; Benítez, Laura Calva; Conan, Pascal; Esparza, Adolfo Contreras Ruiz; Denis, Lionel; Ruiz, Silvia Díaz; Douillet, Pascal; Martinez, Margarita E. Gallegos; Ghiglione, Jean-François; Mendieta, Francisco José Gutiérrez; Origel-Moreno, Montserrat; Garcia, Antonio Zoilo Marquez; Caravaca, Alain Muñoz; Pujo-Pay, Mireille; Alvarado, Rocío Torres; Zavala-Hidalgo, Jorge

    2017-10-01

    The Términos Lagoon is a 2000-km2 wide coastal lagoon linked to the largest river catchment in Mesoamerica. Economic development, together with its ecological importance, led the Mexican government to pronounce the Términos Lagoon and its surrounding wetlands as a Federal protected area for flora and fauna in 1994. It is characterized by small temperature fluctuations, but with two distinct seasons (wet and dry) that control the biological, geochemical, and physical processes and components. This paper presents a review of the available information about the Términos Lagoon. The review shows that the diversity of benthic communities is structured by the balance between marine and riverine inputs and that this structuration strongly influences the benthic metabolism and its coupling with the biogeochemistry of the water column. The paper also presents many specific drivers and recommendations for a long-term environmental survey strategy in the context of the expected Global Change in the Central American region.

  3. MJO simulation in CMIP5 climate models: MJO skill metrics and process-oriented diagnosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ahn, Min-Seop; Kim, Daehyun; Sperber, Kenneth R.

    The Madden-Julian Oscillation (MJO) simulation diagnostics developed by MJO Working Group and the process-oriented MJO simulation diagnostics developed by MJO Task Force are applied to 37 Coupled Model Intercomparison Project phase 5 (CMIP5) models in order to assess model skill in representing amplitude, period, and coherent eastward propagation of the MJO, and to establish a link between MJO simulation skill and parameterized physical processes. Process-oriented diagnostics include the Relative Humidity Composite based on Precipitation (RHCP), Normalized Gross Moist Stability (NGMS), and the Greenhouse Enhancement Factor (GEF). Numerous scalar metrics are developed to quantify the results. Most CMIP5 models underestimate MJOmore » amplitude, especially when outgoing longwave radiation (OLR) is used in the evaluation, and exhibit too fast phase speed while lacking coherence between eastward propagation of precipitation/convection and the wind field. The RHCP-metric, indicative of the sensitivity of simulated convection to low-level environmental moisture, and the NGMS-metric, indicative of the efficiency of a convective atmosphere for exporting moist static energy out of the column, show robust correlations with a large number of MJO skill metrics. The GEF-metric, indicative of the strength of the column-integrated longwave radiative heating due to cloud-radiation interaction, is also correlated with the MJO skill metrics, but shows relatively lower correlations compared to the RHCP- and NGMS-metrics. Our results suggest that modifications to processes associated with moisture-convection coupling and the gross moist stability might be the most fruitful for improving simulations of the MJO. Though the GEF-metric exhibits lower correlations with the MJO skill metrics, the longwave radiation feedback is highly relevant for simulating the weak precipitation anomaly regime that may be important for the establishment of shallow convection and the transition to deep convection.« less

  4. The development and application of landscape evolution models to coupled coast-estuarine environments

    NASA Astrophysics Data System (ADS)

    Morris, Chloe; Coulthard, Tom; Parsons, Daniel R.; Manson, Susan; Barkwith, Andrew

    2017-04-01

    Landscape Evolution Models (LEMs) are proven to be useful tools in understanding the morphodynamics of coast and estuarine systems. However, perhaps owing to the lack of research in this area, current models are not capable of simulating the dynamic interactions between these systems and their co-evolution at the meso-scale. Through a novel coupling of numerical models, this research is designed to explore coupled coastal-estuarine interactions, controls on system behaviour and the influence that environmental change could have. This will contribute to the understanding of the morphodynamics of these systems and how they may behave and evolve over the next century in response to climate changes, with the aim of informing management practices. This goal is being achieved through the modification and coupling of the one-line Coastline Evolution Model (CEM) with the hydrodynamic LEM CAESAR-Lisflood (C-L). The major issues faced with coupling these programs are their differing complexities and the limited graphical visualisations produced by the CEM that hinder the dissemination of results. The work towards overcoming these issues and reported here, include a new version of the CEM that incorporates a range of more complex geomorphological processes and boasts a graphical user interface that guides users through model set-up and projects a live output during model runs. The improved version is a stand-alone tool that can be used for further research projects and for teaching purposes. A sensitivity analysis using the Morris method has been completed to identify which key variables, including wave climate, erosion and weathering values, dominate the control of model behaviour. The model is being applied and tested using the evolution of the Holderness Coast, Humber Estuary and Spurn Point on the east coast of England (UK), which possess diverse geomorphologies and complex, co-evolving sediment pathways. Simulations using the modified CEM are currently being completed to ascertain the processes influential to the morphodynamics and evolution of these systems; presently this includes increasing sea levels and changing wave climate patterns. Outputs and findings from these runs will be presented and discussed, with the aid of the improved graphical visualisations and animations that illustrate the evolution of simulated environments.

  5. VS2DRTI: Simulating Heat and Reactive Solute Transport in Variably Saturated Porous Media.

    PubMed

    Healy, Richard W; Haile, Sosina S; Parkhurst, David L; Charlton, Scott R

    2018-01-29

    Variably saturated groundwater flow, heat transport, and solute transport are important processes in environmental phenomena, such as the natural evolution of water chemistry of aquifers and streams, the storage of radioactive waste in a geologic repository, the contamination of water resources from acid-rock drainage, and the geologic sequestration of carbon dioxide. Up to now, our ability to simulate these processes simultaneously with fully coupled reactive transport models has been limited to complex and often difficult-to-use models. To address the need for a simple and easy-to-use model, the VS2DRTI software package has been developed for simulating water flow, heat transport, and reactive solute transport through variably saturated porous media. The underlying numerical model, VS2DRT, was created by coupling the flow and transport capabilities of the VS2DT and VS2DH models with the equilibrium and kinetic reaction capabilities of PhreeqcRM. Flow capabilities include two-dimensional, constant-density, variably saturated flow; transport capabilities include both heat and multicomponent solute transport; and the reaction capabilities are a complete implementation of geochemical reactions of PHREEQC. The graphical user interface includes a preprocessor for building simulations and a postprocessor for visual display of simulation results. To demonstrate the simulation of multiple processes, the model is applied to a hypothetical example of injection of heated waste water to an aquifer with temperature-dependent cation exchange. VS2DRTI is freely available public domain software. © 2018, National Ground Water Association.

  6. Principal processes within the estuarine salinity gradient: a review.

    PubMed

    Telesh, Irena V; Khlebovich, Vladislav V

    2010-01-01

    The salinity gradient is one of the main features characteristic of any estuarine ecosystem. Within this gradient in a critical salinity range of 5-8 PSU the major biotic and abiotic processes demonstrate non-linear dynamics of change in rates and directions. In estuaries, this salinity range acts as both external ecological factor and physiological characteristics of internal environment of aquatic organisms; it divides living conditions appropriate for freshwater and marine faunas, separates invertebrate communities with different osmotic regulation types, and defines the distribution range of high taxa. In this paper, the non-linearity of biotic processes within the estuarine salinity gradient is illustrated by the data on zooplankton from the Baltic estuaries. The non-tidal Baltic Sea provides a good demonstration of the above phenomena due to gradual changes of environmental factors and relatively stable isohalines. The non-linearity concept coupled with the ecosystem approach served the basis for a new definition of an estuary proposed by the authors. Copyright 2010 Elsevier Ltd. All rights reserved.

  7. Life cycle assessment on microalgal biodiesel production using a hybrid cultivation system.

    PubMed

    Adesanya, Victoria O; Cadena, Erasmo; Scott, Stuart A; Smith, Alison G

    2014-07-01

    A life cycle assessment (LCA) was performed on a putative biodiesel production plant in which the freshwater alga Chlorella vulgaris, was grown using an existing system similar to a published commercial-scale hybrid cultivation. The hybrid system couples airlift tubular photobioreactors with raceway ponds in a two-stage process for high biomass growth and lipid accumulation. The results show that microalgal biodiesel production would have a significantly lower environmental impact than fossil-derived diesel. Based on the functional unit of 1 ton of biodiesel produced, the hybrid cultivation system and hypothetical downstream process (base case) would have 42% and 38% savings in global warming potential (GWP) and fossil-energy requirements (FER) when compared to fossil-derived diesel, respectively. Sensitivity analysis was performed to identify the most influential process parameters on the LCA results. The maximum reduction in GWP and FER was observed under mixotrophic growth conditions with savings of 76% and 75% when compared to conventional diesel, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Electrochemical characterization of monoclinic and orthorhombic Li3CrF6 as positive electrodes in lithium-ion batteries synthesized by a sol-gel process with environmentally benign chemicals

    NASA Astrophysics Data System (ADS)

    Lieser, Georg; Winkler, Volker; Geßwein, Holger; de Biasi, Lea; Glatthaar, Sven; Hoffmann, M. J.; Ehrenberg, Helmut; Binder, Joachim R.

    2015-10-01

    Lithium transition metal fluorides (Li3MF6; M = Fe, V) with cryolite structure are investigated as positive electrode materials for lithium-ion batteries. A novel sol-gel process with trifluoroacetic acid as fluorine source was used to synthesize monoclinic and orthorhombic Li3CrF6. A ball milling process with Li3CrF6, binder, and conductive agent was applied to form a Li3CrF6 composite, which was electrochemically characterized against lithium metal for the first time. The electrochemical properties of two different modifications are quite similar, with a reversible specific capacity of 111 mAhg-1 for monoclinic Li3CrF6 and 106 mAhg-1 for orthorhombic Li3CrF6 (1 eq. Li ≙ 143 mAhg-1). The electrochemically active redox couple CrIII/CrII was confirmed by X-ray photoelectron spectroscopy.

  9. Conceptual design of the CZMIL data processing system (DPS): algorithms and software for fusing lidar, hyperspectral data, and digital images

    NASA Astrophysics Data System (ADS)

    Park, Joong Yong; Tuell, Grady

    2010-04-01

    The Data Processing System (DPS) of the Coastal Zone Mapping and Imaging Lidar (CZMIL) has been designed to automatically produce a number of novel environmental products through the fusion of Lidar, spectrometer, and camera data in a single software package. These new products significantly transcend use of the system as a bathymeter, and support use of CZMIL as a complete coastal and benthic mapping tool. The DPS provides a spinning globe capability for accessing data files; automated generation of combined topographic and bathymetric point clouds; a fully-integrated manual editor and data analysis tool; automated generation of orthophoto mosaics; automated generation of reflectance data cubes from the imaging spectrometer; a coupled air-ocean spectral optimization model producing images of chlorophyll and CDOM concentrations; and a fusion based capability to produce images and classifications of the shallow water seafloor. Adopting a multitasking approach, we expect to achieve computation of the point clouds, DEMs, and reflectance images at a 1:1 processing to acquisition ratio.

  10. Service-Learning in the Environmental Sciences for Teaching Sustainability Science

    NASA Astrophysics Data System (ADS)

    Truebe, S.; Strong, A. L.

    2016-12-01

    Understanding and developing effective strategies for the use of community-engaged learning (service-learning) approaches in the environmental geosciences is an important research need in curricular and pedagogical innovation for sustainability. In 2015, we designed and implemented a new community-engaged learning practicum course through the Earth Systems Program in the School of Earth, Energy and Environmental Sciences at Stanford University focused on regional open space management and land stewardship. Undergraduate and graduate students partnered with three different regional land trust and environmental stewardship organizations to conduct quarter-long research projects ranging from remote sensing studies of historical land use, to fire ecology, to ranchland management, to volunteer retention strategies. Throughout the course, students reflected on the decision-making processes and stewardship actions of the organizations. Two iterations of the course were run in Winter and Fall 2015. Using coded and analyzed pre- and post-course student surveys from the two course iterations, we evaluate undergraduate and graduate student learning outcomes and changes in perceptions and understanding of sustainability science. We find that engagement with community partners to conduct research projects on a wide variety of aspects of open space management, land management, and environmental stewardship (1) increased an understanding of trade-offs inherent in sustainability and resource management and (2) altered student perceptions of the role of scientific information and research in environmental management and decision-making. Furthermore, students initially conceived of open space as purely ecological/biophysical, but by the end of the course, (3) their understanding was of open space as a coupled human/ecological system. This shift is crucial for student development as sustainability scientists.

  11. Symbiotic Gesture and the Sociocognitive Visibility of Grammar in Second Language Acquisition

    ERIC Educational Resources Information Center

    Churchill, Eton; Okada, Hanako; Nishino, Takako; Atkinson, Dwight

    2010-01-01

    This article argues for the embodied and environmentally embedded nature of second language acquisition (SLA). Through fine-grained analysis of interaction using Goodwin's (2003a) concept of "symbiotic gesture"--gesture coupled with its rich environmental context to produce complex social action--we illustrate how a tutor, learner, and grammar…

  12. A review of promising new immunoassay technology for monitoring forest herbicides

    Treesearch

    Charles K. McMahon

    1993-01-01

    Rising costs of classical instrumental methods of chemical analysis coupled with an increasing need for environmental monitoring has lead to the development of highly sensitive, low-cost immunochemical methods of analysis for the detection of environmental contaminants. These methods known simply as immunoassays are chemical assays which use antibodies as reagents. A...

  13. The EVNATURB project: toward an operational platform to assess Blue Green Solutions eco-systemic services in urban environment

    NASA Astrophysics Data System (ADS)

    Schertzer, D. J. M.; Versini, P. A.; Tchiguirinskaia, I.

    2017-12-01

    Urban areas are facing an expected increase in intensity and frequency of extreme weather events due to climate change. Combined with unsustainable urbanization, this should exacerbate the environmental consequences related to the water cycle as stormwater management issues, urban heat island increase and biodiversity degradation. Blue Green Solutions (BGS), such as green roofs, vegetated swales or urban ponds, appear to be particularly efficient to reduce the potential impact of new and existing urban developments with respect to these issues. Based on this statement, the French ANR EVNATURB project aims to develop a platform to assess the eco-systemic services provided by BGS and related with the previously mentioned issues. By proposing a multi-disciplinary consortium coupling monitoring, modelling and prospecting, it attempts to tackle several scientific issues currently limiting BGS wide implementation. Based on high resolution monitored sites and modelling tools, space-time variability of the related physical processes will be studied over a wide range of scales (from the material to the district scale), as well as local social-environmental stakes and constraints, to better consider the complexity of the urban environment. The EVNATURB platform developed during the project is intended for every stakeholder involved in urban development projects (planners, architects, engineering and environmental certification companies…) and will help them to implement BGS and evaluate which ones are the most appropriate for a particular project depending on its environmental objectives and constraints, and particularly for obtaining environmental certification.

  14. Biodiversity maintenance in food webs with regulatory environmental feedbacks.

    PubMed

    Bagdassarian, Carey K; Dunham, Amy E; Brown, Christopher G; Rauscher, Daniel

    2007-04-21

    Although the food web is one of the most fundamental and oldest concepts in ecology, elucidating the strategies and structures by which natural communities of species persist remains a challenge to empirical and theoretical ecologists. We show that simple regulatory feedbacks between autotrophs and their environment when embedded within complex and realistic food-web models enhance biodiversity. The food webs are generated through the niche-model algorithm and coupled with predator-prey dynamics, with and without environmental feedbacks at the autotroph level. With high probability and especially at lower, more realistic connectance levels, regulatory environmental feedbacks result in fewer species extinctions, that is, in increased species persistence. These same feedback couplings, however, also sensitize food webs to environmental stresses leading to abrupt collapses in biodiversity with increased forcing. Feedback interactions between species and their material environments anchor food-web persistence, adding another dimension to biodiversity conservation. We suggest that the regulatory features of two natural systems, deep-sea tubeworms with their microbial consortia and a soil ecosystem manifesting adaptive homeostatic changes, can be embedded within niche-model food-web dynamics.

  15. Regression of non-linear coupling of noise in LIGO detectors

    NASA Astrophysics Data System (ADS)

    Da Silva Costa, C. F.; Billman, C.; Effler, A.; Klimenko, S.; Cheng, H.-P.

    2018-03-01

    In 2015, after their upgrade, the advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors started acquiring data. The effort to improve their sensitivity has never stopped since then. The goal to achieve design sensitivity is challenging. Environmental and instrumental noise couple to the detector output with different, linear and non-linear, coupling mechanisms. The noise regression method we use is based on the Wiener–Kolmogorov filter, which uses witness channels to make noise predictions. We present here how this method helped to determine complex non-linear noise couplings in the output mode cleaner and in the mirror suspension system of the LIGO detector.

  16. Processing device with self-scrubbing logic

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wojahn, Christopher K.

    An apparatus includes a processing unit including a configuration memory and self-scrubber logic coupled to read the configuration memory to detect compromised data stored in the configuration memory. The apparatus also includes a watchdog unit external to the processing unit and coupled to the self-scrubber logic to detect a failure in the self-scrubber logic. The watchdog unit is coupled to the processing unit to selectively reset the processing unit in response to detecting the failure in the self-scrubber logic. The apparatus also includes an external memory external to the processing unit and coupled to send configuration data to the configurationmore » memory in response to a data feed signal outputted by the self-scrubber logic.« less

  17. Separation of the metallic and non-metallic fraction from printed circuit boards employing green technology.

    PubMed

    Estrada-Ruiz, R H; Flores-Campos, R; Gámez-Altamirano, H A; Velarde-Sánchez, E J

    2016-07-05

    The generation of electrical and electronic waste is increasing day by day; recycling is attractive because of the metallic fraction containing these. Nevertheless, conventional techniques are highly polluting. The comminution of the printed circuit boards followed by an inverse flotation process is a clean technique that allows one to separate the metallic fraction from the non-metallic fraction. It was found that particle size and superficial air velocity are the main variables in the separation of the different fractions. In this way an efficient separation is achieved by avoiding the environmental contamination coupled with the possible utilization of the different fractions obtained. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. BIOGEOCHEMICAL STUDIES OF PHOTOSYNTHETIC MICROBIAL MATS AND THEIR BIOTA

    NASA Technical Reports Server (NTRS)

    DesMarais, David; Discipulo, M.; Turk, K.; Londry, K. L.

    2005-01-01

    Photosynthetic microbial mats offer an opportunity to define holistic functionality at the millimeter scale. At the same time. their biogeochemistry contributes to environmental processes on a planetary scale. These mats are possibly direct descendents of the most ancient biological communities; communities in which oxygenic photosynthesis might have been invented. Mats provide one of the best natural systems to study how microbial populations associate to control dynamic biogeochemical gradients. These are self- sustaining, complete ecosystems in which light energy absorbed over a dial (24 hour) cycle drives the synthesis of spatially-organized, diverse biomass. Tightly-coupled microorganisms in the mat have specialized metabolisms that catalyze transformations of carbon, nitrogen, sulfur, and a host of other elements.

  19. Nanomaterials for renewable energy

    DOE PAGES

    Chen, Shimou; Li, Liang; Sun, Hanwen; ...

    2015-05-19

    With demand for sustainable energy, resource, and environment protection, new material technologies are constantly expanding during the last few couple of decades. An intensive attention has been given by the scientific communities. In particular, nanomaterials are increasingly playing an active role either by increasing the efficiency of the energy storage and conversion processes or by improving the device design and performance. This special issue presents recent research advances in various aspects of energy storage technologies, advanced batteries, fuel cells, solar cell, biofuels, and so on. Design and synthesis of novel materials have demonstrated great impact on the utilization of themore » sustainable energy, which need to solve the increasing shortage of resource and the issues of environmental pollution.« less

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Manteufel, R.D.; Ahola, M.P.; Turner, D.R.

    A literature review has been conducted to determine the state of knowledge available in the modeling of coupled thermal (T), hydrologic (H), mechanical (M), and chemical (C) processes relevant to the design and/or performance of the proposed high-level waste (HLW) repository at Yucca Mountain, Nevada. The review focuses on identifying coupling mechanisms between individual processes and assessing their importance (i.e., if the coupling is either important, potentially important, or negligible). The significance of considering THMC-coupled processes lies in whether or not the processes impact the design and/or performance objectives of the repository. A review, such as reported here, is usefulmore » in identifying which coupled effects will be important, hence which coupled effects will need to be investigated by the US Nuclear Regulatory Commission in order to assess the assumptions, data, analyses, and conclusions in the design and performance assessment of a geologic reposit``. Although this work stems from regulatory interest in the design of the geologic repository, it should be emphasized that the repository design implicitly considers all of the repository performance objectives, including those associated with the time after permanent closure. The scope of this review is considered beyond previous assessments in that it attempts with the current state-of-knowledge) to determine which couplings are important, and identify which computer codes are currently available to model coupled processes.« less

  1. Fostering new relational experience: clinical process in couple psychotherapy.

    PubMed

    Marmarosh, Cheri L

    2014-03-01

    One of the most critical goals for couple psychotherapy is to foster a new relational experience in the session where the couple feels safe enough to reveal more vulnerable emotions and to explore their defensive withdrawal, aggressive attacking, or blaming. The lived intimate experience in the session offers the couple an opportunity to gain integrative insight into their feelings, expectations, and behaviors that ultimately hinder intimacy. The clinical processes that are necessary include empathizing with the couple and facilitating safety within the session, looking for opportunities to explore emotions, ruptures, and unconscious motivations that maintain distance in the relationship, and creating a new relational experience in the session that has the potential to engender integrative insight. These clinical processes will be presented with empirical support. Experts from a session will be used to highlight how these processes influence the couple and promote increased intimacy. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  2. An adaptive deep-coupled GNSS/INS navigation system with hybrid pre-filter processing

    NASA Astrophysics Data System (ADS)

    Wu, Mouyan; Ding, Jicheng; Zhao, Lin; Kang, Yingyao; Luo, Zhibin

    2018-02-01

    The deep-coupling of a global navigation satellite system (GNSS) with an inertial navigation system (INS) can provide accurate and reliable navigation information. There are several kinds of deeply-coupled structures. These can be divided mainly into coherent and non-coherent pre-filter based structures, which have their own strong advantages and disadvantages, especially in accuracy and robustness. In this paper, the existing pre-filters of the deeply-coupled structures are analyzed and modified to improve them firstly. Then, an adaptive GNSS/INS deeply-coupled algorithm with hybrid pre-filters processing is proposed to combine the advantages of coherent and non-coherent structures. An adaptive hysteresis controller is designed to implement the hybrid pre-filters processing strategy. The simulation and vehicle test results show that the adaptive deeply-coupled algorithm with hybrid pre-filters processing can effectively improve navigation accuracy and robustness, especially in a GNSS-challenged environment.

  3. AWIPS II+: An Open-Source SOA Solution Enabling Environmental Remote Sensing Integration, Analysis, and Decision Support

    NASA Astrophysics Data System (ADS)

    Ardanuy, P. E.; Hood, C. A.; Moran, S. G.; Ritchie, A. A.; Tarro, A. M.; Nappi, A. J.

    2008-12-01

    Our shared future demands a renewed focus on sound environment stewardship-on the GEOSS socioeconomic imperatives, as well as the interdisciplinary relationships interconnecting our environment, climate, ecosystems, energy, carbon, water-and national security. Data volumes are now measured in the many petabytes. An increasingly urgent and accelerated tempo of changing requirements and responsive solutions demands data exploitation, and transparent, seamless, effortless, bidirectional, and interdisciplinary interoperability across models and observations. There is today a robust working paradigm established with the Advanced Weather Interactive Processing System (AWIPS)-NOAA/NWS's information integration and fusion capability. This process model extends vertically, and seamlessly, from environmental sensing through the direct delivery of societal benefit. NWS, via AWIPS, is the primary source of weather forecast and warning information in the nation. AWIPS is the tested and proven "the nerve center of operations" at all 122 NWS Weather Forecast Offices and 13 River Forecast Centers. Raytheon, in partnership with NOAA, has now evolved AWIPS into an open-source 2nd generation capability to satisfy climate, ecosystems, weather, and water mission goals. Just as AWIPS II supports NOAA decision- making, it is at the same time a platform funded by Raytheon IRAD and Government investment that can be cost-effectively leveraged across all of the GEOSS and IEOS societal benefit areas. The core principles in the AWIPS II evolution to a service-oriented architecture (SOA) were to minimize coupling, increase cohesion, minimize size of code base, maximize simplicity, and incorporate a pull-style data flow. We focused on "ilities" to drive the new AWIPS architecture-our shared architecture framework vision included six elements: - Create a new, low-cost framework for hosting a full range of environmental services, including thick-client visualization via virtual Earth's and GIS - Scale down framework to a small laptop and through workstations to clusters of enterprise servers without software change - "Plug-n-play"- plug-ins can be hot deployable, or system cycled to pick up new plug-ins - Base the framework on highly reusable design patterns that maximize reuse and have datatype independence and fast adaptability - Open Source leveraged to maximize reuse - "Gaming-style" interaction with the data This talk addresses the challenges that we meet to realize benefits in applications that couple environmental data from many disparate remote sensing and ancillary sources and disciplines. By leveraging the existing AWIPS II weather, water, ecosystems, and climate functionality and these six elements, along with well- thought-out displays with the end user's specific needs in mind, we demonstrate an easily adapted, extremely powerful, open-source remote sensing software tool that will help non-geospatial-experts make better use of these remote sensing resources to enhance environmental mapping and analysis and help guide environmental decision making at the national, regional, local and citizen levels.

  4. Developing predictive insight into changing water systems: use-inspired hydrologic science for the Anthropocene

    NASA Astrophysics Data System (ADS)

    Thompson, S. E.; Sivapalan, M.; Harman, C. J.; Srinivasan, V.; Hipsey, M. R.; Reed, P.; Montanari, A.; Blöschl, G.

    2013-12-01

    Globally, many different kinds of water resources management issues call for policy- and infrastructure-based responses. Yet responsible decision-making about water resources management raises a fundamental challenge for hydrologists: making predictions about water resources on decadal- to century-long timescales. Obtaining insight into hydrologic futures over 100 yr timescales forces researchers to address internal and exogenous changes in the properties of hydrologic systems. To do this, new hydrologic research must identify, describe and model feedbacks between water and other changing, coupled environmental subsystems. These models must be constrained to yield useful insights, despite the many likely sources of uncertainty in their predictions. Chief among these uncertainties are the impacts of the increasing role of human intervention in the global water cycle - a defining challenge for hydrology in the Anthropocene. Here we present a research agenda that proposes a suite of strategies to address these challenges from the perspectives of hydrologic science research. The research agenda focuses on the development of co-evolutionary hydrologic modeling to explore coupling across systems, and to address the implications of this coupling on the long-time behavior of the coupled systems. Three research directions support the development of these models: hydrologic reconstruction, comparative hydrology and model-data learning. These strategies focus on understanding hydrologic processes and feedbacks over long timescales, across many locations, and through strategic coupling of observational and model data in specific systems. We highlight the value of use-inspired and team-based science that is motivated by real-world hydrologic problems but targets improvements in fundamental understanding to support decision-making and management. Fully realizing the potential of this approach will ultimately require detailed integration of social science and physical science understanding of water systems, and is a priority for the developing field of sociohydrology.

  5. Client Discourses on the Process of Seeking Same-Sex Couple Counselling

    ERIC Educational Resources Information Center

    Grove, Jan; Peel, Elizabeth; Owen-Pugh, Valerie

    2013-01-01

    How same-sex couples manage the process of seeking help for their relationships is an under-researched area. Twelve semi-structured interviews were conducted with 16 people who had engaged in same-sex couple counselling, and were analysed using discourse analysis. The ways in which the couples positioned themselves as part of a "minority…

  6. Signatures of Förster and Dexter transfer processes in coupled nanostructures for linear and two-dimensional coherent optical spectroscopy

    NASA Astrophysics Data System (ADS)

    Specht, Judith F.; Richter, Marten

    2015-03-01

    In this manuscript, we study the impact of the two Coulomb induced resonance energy transfer processes, Förster and Dexter coupling, on the spectral signatures obtained by double quantum coherence spectroscopy. We show that the specific coupling characteristics allow us to identify the underlying excitation transfer mechanism by means of specific signatures in coherent spectroscopy. Therefore, we control the microscopic calculated coupling strength of spin preserving and spin flipping Förster transfer processes by varying the mutual orientation of the two quantum emitters. The calculated spectra reveal the optical selection rules altered by Förster and Dexter coupling between two semiconductor quantum dots. We show that Dexter coupling between bright and dark two-exciton states occurs.

  7. Observing Graphene Grow: Catalyst–Graphene Interactions during Scalable Graphene Growth on Polycrystalline Copper

    PubMed Central

    2013-01-01

    Complementary in situ X-ray photoelectron spectroscopy (XPS), X-ray diffractometry, and environmental scanning electron microscopy are used to fingerprint the entire graphene chemical vapor deposition process on technologically important polycrystalline Cu catalysts to address the current lack of understanding of the underlying fundamental growth mechanisms and catalyst interactions. Graphene forms directly on metallic Cu during the high-temperature hydrocarbon exposure, whereby an upshift in the binding energies of the corresponding C1s XPS core level signatures is indicative of coupling between the Cu catalyst and the growing graphene. Minor carbon uptake into Cu can under certain conditions manifest itself as carbon precipitation upon cooling. Postgrowth, ambient air exposure even at room temperature decouples the graphene from Cu by (reversible) oxygen intercalation. The importance of these dynamic interactions is discussed for graphene growth, processing, and device integration. PMID:24041311

  8. Groundwater–surface water mixing shifts ecological assembly processes and stimulates organic carbon turnover

    PubMed Central

    Stegen, James C.; Fredrickson, James K.; Wilkins, Michael J.; Konopka, Allan E.; Nelson, William C.; Arntzen, Evan V.; Chrisler, William B.; Chu, Rosalie K.; Danczak, Robert E.; Fansler, Sarah J.; Kennedy, David W.; Resch, Charles T.; Tfaily, Malak

    2016-01-01

    Environmental transitions often result in resource mixtures that overcome limitations to microbial metabolism, resulting in biogeochemical hotspots and moments. Riverine systems, where groundwater mixes with surface water (the hyporheic zone), are spatially complex and temporally dynamic, making development of predictive models challenging. Spatial and temporal variations in hyporheic zone microbial communities are a key, but understudied, component of riverine biogeochemical function. Here, to investigate the coupling among groundwater–surface water mixing, microbial communities and biogeochemistry, we apply ecological theory, aqueous biogeochemistry, DNA sequencing and ultra-high-resolution organic carbon profiling to field samples collected across times and locations representing a broad range of mixing conditions. Our results indicate that groundwater–surface water mixing in the hyporheic zone stimulates heterotrophic respiration, alters organic carbon composition, causes ecological processes to shift from stochastic to deterministic and is associated with elevated abundances of microbial taxa that may degrade a broad suite of organic compounds. PMID:27052662

  9. Groundwater-surface water mixing shifts ecological assembly processes and stimulates organic carbon turnover.

    PubMed

    Stegen, James C; Fredrickson, James K; Wilkins, Michael J; Konopka, Allan E; Nelson, William C; Arntzen, Evan V; Chrisler, William B; Chu, Rosalie K; Danczak, Robert E; Fansler, Sarah J; Kennedy, David W; Resch, Charles T; Tfaily, Malak

    2016-04-07

    Environmental transitions often result in resource mixtures that overcome limitations to microbial metabolism, resulting in biogeochemical hotspots and moments. Riverine systems, where groundwater mixes with surface water (the hyporheic zone), are spatially complex and temporally dynamic, making development of predictive models challenging. Spatial and temporal variations in hyporheic zone microbial communities are a key, but understudied, component of riverine biogeochemical function. Here, to investigate the coupling among groundwater-surface water mixing, microbial communities and biogeochemistry, we apply ecological theory, aqueous biogeochemistry, DNA sequencing and ultra-high-resolution organic carbon profiling to field samples collected across times and locations representing a broad range of mixing conditions. Our results indicate that groundwater-surface water mixing in the hyporheic zone stimulates heterotrophic respiration, alters organic carbon composition, causes ecological processes to shift from stochastic to deterministic and is associated with elevated abundances of microbial taxa that may degrade a broad suite of organic compounds.

  10. How coalescing droplets jump.

    PubMed

    Enright, Ryan; Miljkovic, Nenad; Sprittles, James; Nolan, Kevin; Mitchell, Robert; Wang, Evelyn N

    2014-10-28

    Surface engineering at the nanoscale is a rapidly developing field that promises to impact a range of applications including energy production, water desalination, self-cleaning and anti-icing surfaces, thermal management of electronics, microfluidic platforms, and environmental pollution control. As the area advances, more detailed insights of dynamic wetting interactions on these surfaces are needed. In particular, the coalescence of two or more droplets on ultra-low adhesion surfaces leads to droplet jumping. Here we show, through detailed measurements of jumping droplets during water condensation coupled with numerical simulations of binary droplet coalescence, that this process is fundamentally inefficient with only a small fraction of the available excess surface energy (≲ 6%) convertible into translational kinetic energy. These findings clarify the role of internal fluid dynamics during the jumping droplet coalescence process and underpin the development of systems that can harness jumping droplets for a wide range of applications.

  11. Nitrogen fixation sustained productivity in the wake of the Palaeoproterozoic Great Oxygenation Event.

    PubMed

    Luo, Genming; Junium, Christopher K; Izon, Gareth; Ono, Shuhei; Beukes, Nicolas J; Algeo, Thomas J; Cui, Ying; Xie, Shucheng; Summons, Roger E

    2018-03-07

    The marine nitrogen cycle is dominated by redox-controlled biogeochemical processes and, therefore, is likely to have been revolutionised in response to Earth-surface oxygenation. The details, timing, and trajectory of nitrogen cycle evolution, however, remain elusive. Here we couple nitrogen and carbon isotope records from multiple drillcores through the Rooihoogte-Timeball Hill Formations from across the Carletonville area of the Kaapvaal Craton where the Great Oxygenation Event (GOE) and its aftermath are recorded. Our data reveal that aerobic nitrogen cycling, featuring metabolisms involving nitrogen oxyanions, was well established prior to the GOE and that ammonium may have dominated the dissolved nitrogen inventory. Pronounced signals of diazotrophy imply a stepwise evolution, with a temporary intermediate stage where both ammonium and nitrate may have been scarce. We suggest that the emergence of the modern nitrogen cycle, with metabolic processes that approximate their contemporary balance, was retarded by low environmental oxygen availability.

  12. Hillslope hydrology and stability

    USGS Publications Warehouse

    Lu, Ning; Godt, Jonathan

    2012-01-01

    Landslides are caused by a failure of the mechanical balance within hillslopes. This balance is governed by two coupled physical processes: hydrological or subsurface flow and stress. The stabilizing strength of hillslope materials depends on effective stress, which is diminished by rainfall. This book presents a cutting-edge quantitative approach to understanding hydro-mechanical processes across variably saturated hillslope environments and to the study and prediction of rainfall-induced landslides. Topics covered include historic synthesis of hillslope geomorphology and hydrology, total and effective stress distributions, critical reviews of shear strength of hillslope materials and different bases for stability analysis. Exercises and homework problems are provided for students to engage with the theory in practice. This is an invaluable resource for graduate students and researchers in hydrology, geomorphology, engineering geology, geotechnical engineering and geomechanics and for professionals in the fields of civil and environmental engineering and natural hazard analysis.

  13. Traveling Rocky Roads: The Consequences of Transcription-Blocking DNA Lesions on RNA Polymerase II.

    PubMed

    Steurer, Barbara; Marteijn, Jurgen A

    2017-10-27

    The faithful transcription of eukaryotic genes by RNA polymerase II (RNAP2) is crucial for proper cell function and tissue homeostasis. However, transcription-blocking DNA lesions of both endogenous and environmental origin continuously challenge the progression of elongating RNAP2. The stalling of RNAP2 on a transcription-blocking lesion triggers a series of highly regulated events, including RNAP2 processing to make the lesion accessible for DNA repair, R-loop-mediated DNA damage signaling, and the initiation of transcription-coupled DNA repair. The correct execution and coordination of these processes is vital for resuming transcription following the successful repair of transcription-blocking lesions. Here, we outline recent insights into the molecular consequences of RNAP2 stalling on transcription-blocking DNA lesions and how these lesions are resolved to restore mRNA synthesis. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  14. Periodic processes in vapor phase biofiltration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moe, W.M.; Irvine, R.L.

    1998-07-01

    Most industrial processes and environmental remediation activities generate large volumes of air contaminated with low concentrations of volatile organic compounds. Carbon adsorption is the most widely used conventional treatment technology, but it has many drawbacks including secondary waste streams and excessive regeneration costs. Biofiltration, a microbial-based treatment technology, removes and biodegrades contaminants from a wide variety of waste streams without the disadvantages of carbon adsorption. In biofiltration, contaminated air flows through a packed bed containing microorganisms which convert contaminants primarily into carbon dioxide, water, and biomass. This paper describes how periodically operated, controlled unsteady state conditions were imposed on biofiltersmore » which used a new polyurethane foam medium that couples high porosity, suitable pore size, and low density with an ability to sorb water. The potential benefits associated with the controlled, unsteady-state operation of biofilters containing this new polyurethane foam medium are described herein. An example system treating a toluene contaminated waste gas is presented.« less

  15. Extracellular localization of the diterpene sclareol in clary sage (Salvia sclarea L., Lamiaceae).

    PubMed

    Caissard, Jean-Claude; Olivier, Thomas; Delbecque, Claire; Palle, Sabine; Garry, Pierre-Philippe; Audran, Arthur; Valot, Nadine; Moja, Sandrine; Nicolé, Florence; Magnard, Jean-Louis; Legrand, Sylvain; Baudino, Sylvie; Jullien, Frédéric

    2012-01-01

    Sclareol is a high-value natural product obtained by solid/liquid extraction of clary sage (Salvia sclarea L.) inflorescences. Because processes of excretion and accumulation of this labdane diterpene are unknown, the aim of this work was to gain knowledge on its sites of accumulation in planta. Samples were collected in natura or during different steps of the industrial process of extraction (steam distillation and solid/liquid extraction). Samples were then analysed with a combination of complementary analytical techniques (gas chromatography coupled to a mass spectrometer, polarized light microscopy, environmental scanning electron microscopy, two-photon fluorescence microscopy, second harmonic generation microscopy). According to the literature, it is hypothesized that sclareol is localized in oil pockets of secretory trichomes. This study demonstrates that this is not the case and that sclareol accumulates in a crystalline epicuticular form, mostly on calyces.

  16. Extracellular Localization of the Diterpene Sclareol in Clary Sage (Salvia sclarea L., Lamiaceae)

    PubMed Central

    Caissard, Jean-Claude; Olivier, Thomas; Delbecque, Claire; Palle, Sabine; Garry, Pierre-Philippe; Audran, Arthur; Valot, Nadine; Moja, Sandrine; Nicolé, Florence; Magnard, Jean-Louis; Legrand, Sylvain; Baudino, Sylvie; Jullien, Frédéric

    2012-01-01

    Sclareol is a high-value natural product obtained by solid/liquid extraction of clary sage (Salvia sclarea L.) inflorescences. Because processes of excretion and accumulation of this labdane diterpene are unknown, the aim of this work was to gain knowledge on its sites of accumulation in planta. Samples were collected in natura or during different steps of the industrial process of extraction (steam distillation and solid/liquid extraction). Samples were then analysed with a combination of complementary analytical techniques (gas chromatography coupled to a mass spectrometer, polarized light microscopy, environmental scanning electron microscopy, two-photon fluorescence microscopy, second harmonic generation microscopy). According to the literature, it is hypothesized that sclareol is localized in oil pockets of secretory trichomes. This study demonstrates that this is not the case and that sclareol accumulates in a crystalline epicuticular form, mostly on calyces. PMID:23133579

  17. Modeling Electronic-Nuclear Interactions for Excitation Energy Transfer Processes in Light-Harvesting Complexes.

    PubMed

    Lee, Mi Kyung; Coker, David F

    2016-08-18

    An accurate approach for computing intermolecular and intrachromophore contributions to spectral densities to describe the electronic-nuclear interactions relevant for modeling excitation energy transfer processes in light harvesting systems is presented. The approach is based on molecular dynamics (MD) calculations of classical correlation functions of long-range contributions to excitation energy fluctuations and a separate harmonic analysis and single-point gradient quantum calculations for electron-intrachromophore vibrational couplings. A simple model is also presented that enables detailed analysis of the shortcomings of standard MD-based excitation energy fluctuation correlation function approaches. The method introduced here avoids these problems, and its reliability is demonstrated in accurate predictions for bacteriochlorophyll molecules in the Fenna-Matthews-Olson pigment-protein complex, where excellent agreement with experimental spectral densities is found. This efficient approach can provide instantaneous spectral densities for treating the influence of fluctuations in environmental dissipation on fast electronic relaxation.

  18. Nanofiltration-Enabled In Situ Solvent and Reagent Recycle for Sustainable Continuous-Flow Synthesis.

    PubMed

    Fodi, Tamas; Didaskalou, Christos; Kupai, Jozsef; Balogh, Gyorgy T; Huszthy, Peter; Szekely, Gyorgy

    2017-09-11

    Solvent usage in the pharmaceutical sector accounts for as much as 90 % of the overall mass during manufacturing processes. Consequently, solvent consumption poses significant costs and environmental burdens. Continuous processing, in particular continuous-flow reactors, have great potential for the sustainable production of pharmaceuticals but subsequent downstream processing remains challenging. Separation processes for concentrating and purifying chemicals can account for as much as 80 % of the total manufacturing costs. In this work, a nanofiltration unit was coupled to a continuous-flow rector for in situ solvent and reagent recycling. The nanofiltration unit is straightforward to implement and simple to control during continuous operation. The hybrid process operated continuously over six weeks, recycling about 90 % of the solvent and reagent. Consequently, the E-factor and the carbon footprint were reduced by 91 % and 19 %, respectively. Moreover, the nanofiltration unit led to a solution of the product eleven times more concentrated than the reaction mixture and increased the purity from 52.4 % to 91.5 %. The boundaries for process conditions were investigated to facilitate implementation of the methodology by the pharmaceutical sector. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Maximum entropy production in environmental and ecological systems.

    PubMed

    Kleidon, Axel; Malhi, Yadvinder; Cox, Peter M

    2010-05-12

    The coupled biosphere-atmosphere system entails a vast range of processes at different scales, from ecosystem exchange fluxes of energy, water and carbon to the processes that drive global biogeochemical cycles, atmospheric composition and, ultimately, the planetary energy balance. These processes are generally complex with numerous interactions and feedbacks, and they are irreversible in their nature, thereby producing entropy. The proposed principle of maximum entropy production (MEP), based on statistical mechanics and information theory, states that thermodynamic processes far from thermodynamic equilibrium will adapt to steady states at which they dissipate energy and produce entropy at the maximum possible rate. This issue focuses on the latest development of applications of MEP to the biosphere-atmosphere system including aspects of the atmospheric circulation, the role of clouds, hydrology, vegetation effects, ecosystem exchange of energy and mass, biogeochemical interactions and the Gaia hypothesis. The examples shown in this special issue demonstrate the potential of MEP to contribute to improved understanding and modelling of the biosphere and the wider Earth system, and also explore limitations and constraints to the application of the MEP principle.

  20. Nutrigenomics at the Interface of Aging, Lifespan, and Cancer Prevention123

    PubMed Central

    Riscuta, Gabriela

    2016-01-01

    The percentage of elderly people with associated age-related health deterioration, including cancer, has been increasing for decades. Among age-related diseases, the incidence of cancer has grown substantially, in part because of the overlap of some molecular pathways between cancer and aging. Studies with model organisms suggest that aging and age-related conditions are manipulable processes that can be modified by both genetic and environmental factors, including dietary habits. Variations in genetic backgrounds likely lead to differential responses to dietary changes and account for some of the inconsistencies found in the literature. The intricacies of the aging process, coupled with the interrelational role of bioactive food components on gene expression, make this review a complex undertaking. Nevertheless, intriguing evidence suggests that dietary habits can manipulate the aging process and/or its consequences and potentially may have unprecedented health benefits. The present review focuses on 4 cellular events: telomerase activity, bioenergetics, DNA repair, and oxidative stress. These processes are linked to both aging and cancer risk, and their alteration in animal models by selected food components is evident. PMID:27558581

  1. Biogeochemical Processes in Microbial Ecosystems

    NASA Technical Reports Server (NTRS)

    DesMarais, David J.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    The hierarchical organization of microbial ecosystems determines process rates that shape Earth's environment, create the biomarker sedimentary and atmospheric signatures of life and define the stage upon which major evolutionary events occurred. In order to understand how microorganisms have shaped the global environment of Earth and potentially, other worlds, we must develop an experimental paradigm that links biogeochemical processes with ever-changing temporal and spatial distributions of microbial population, and their metabolic properties. Photosynthetic microbial mats offer an opportunity to define holistic functionality at the millimeter scale. At the same time, their Biogeochemistry contributes to environmental processes on a planetary scale. These mats are possibly direct descendents of the most ancient biological communities; communities in which oxygenic photosynthesis might have been invented. Mats provide one of the best natural systems to study how microbial populations associate to control dynamic biogeochemical gradients. These are self-sustaining, complete ecosystems in which light energy absorbed over a diel (24 hour) cycle drives the synthesis of spatially-organized, diverse biomass. Tightly-coupled microorganisms in the mat have specialized metabolisms that catalyze transformations of carbon, nitrogen. sulfur, and a host of other elements.

  2. Nutrigenomics at the Interface of Aging, Lifespan, and Cancer Prevention.

    PubMed

    Riscuta, Gabriela

    2016-10-01

    The percentage of elderly people with associated age-related health deterioration, including cancer, has been increasing for decades. Among age-related diseases, the incidence of cancer has grown substantially, in part because of the overlap of some molecular pathways between cancer and aging. Studies with model organisms suggest that aging and age-related conditions are manipulable processes that can be modified by both genetic and environmental factors, including dietary habits. Variations in genetic backgrounds likely lead to differential responses to dietary changes and account for some of the inconsistencies found in the literature. The intricacies of the aging process, coupled with the interrelational role of bioactive food components on gene expression, make this review a complex undertaking. Nevertheless, intriguing evidence suggests that dietary habits can manipulate the aging process and/or its consequences and potentially may have unprecedented health benefits. The present review focuses on 4 cellular events: telomerase activity, bioenergetics, DNA repair, and oxidative stress. These processes are linked to both aging and cancer risk, and their alteration in animal models by selected food components is evident. © 2016 American Society for Nutrition.

  3. Opportunities and Examples for Integration of Socio-environmental Approaches to Support Climate-informed Decisions

    NASA Astrophysics Data System (ADS)

    Kenney, M. A.

    2014-12-01

    Climate and environmental decisions require science that couples human and natural systems to quantify or articulate the observed physical, natural, and societal changes or likely consequences of different decision options. Despite the need for such policy-relevant research, multidisciplinary collaborations can be wrought with challenges of data integration, model interoperability, and communication across disciplinary divides. In this talk, I will present several examples where I have collaborated with colleagues from the physical, natural, and social sciences to develop novel, actionable science to inform decision-making. Specifically, I will discuss a cost analysis of water and sediment diversions to optimize land building in the Mississippi River delta (winner of American Geophysical Union Water Resources Research Editor's Choice Award 2014) and the development of a National Climate Indicator System that uses knowledge across the physical, natural, and social sciences to establish an end-to-end indicator system of climate changes, impacts, vulnerabilities, and responses. The latter project is in the process of moving from research to operations, an additional challenge and opportunity, as we work with the U.S. Global Change Research Program and their affiliated Federal agencies to establish it beyond the research prototype. Using these examples, I will provide some lessons learned that would have general applicability to socio-environmental research collaborations and integration of data, models, and information systems to support climate and environmental decision-making.

  4. Prediction of crime occurrence from multi-modal data using deep learning

    PubMed Central

    Kang, Hyeon-Woo

    2017-01-01

    In recent years, various studies have been conducted on the prediction of crime occurrences. This predictive capability is intended to assist in crime prevention by facilitating effective implementation of police patrols. Previous studies have used data from multiple domains such as demographics, economics, and education. Their prediction models treat data from different domains equally. These methods have problems in crime occurrence prediction, such as difficulty in discovering highly nonlinear relationships, redundancies, and dependencies between multiple datasets. In order to enhance crime prediction models, we consider environmental context information, such as broken windows theory and crime prevention through environmental design. In this paper, we propose a feature-level data fusion method with environmental context based on a deep neural network (DNN). Our dataset consists of data collected from various online databases of crime statistics, demographic and meteorological data, and images in Chicago, Illinois. Prior to generating training data, we select crime-related data by conducting statistical analyses. Finally, we train our DNN, which consists of the following four kinds of layers: spatial, temporal, environmental context, and joint feature representation layers. Coupled with crucial data extracted from various domains, our fusion DNN is a product of an efficient decision-making process that statistically analyzes data redundancy. Experimental performance results show that our DNN model is more accurate in predicting crime occurrence than other prediction models. PMID:28437486

  5. Prediction of crime occurrence from multi-modal data using deep learning.

    PubMed

    Kang, Hyeon-Woo; Kang, Hang-Bong

    2017-01-01

    In recent years, various studies have been conducted on the prediction of crime occurrences. This predictive capability is intended to assist in crime prevention by facilitating effective implementation of police patrols. Previous studies have used data from multiple domains such as demographics, economics, and education. Their prediction models treat data from different domains equally. These methods have problems in crime occurrence prediction, such as difficulty in discovering highly nonlinear relationships, redundancies, and dependencies between multiple datasets. In order to enhance crime prediction models, we consider environmental context information, such as broken windows theory and crime prevention through environmental design. In this paper, we propose a feature-level data fusion method with environmental context based on a deep neural network (DNN). Our dataset consists of data collected from various online databases of crime statistics, demographic and meteorological data, and images in Chicago, Illinois. Prior to generating training data, we select crime-related data by conducting statistical analyses. Finally, we train our DNN, which consists of the following four kinds of layers: spatial, temporal, environmental context, and joint feature representation layers. Coupled with crucial data extracted from various domains, our fusion DNN is a product of an efficient decision-making process that statistically analyzes data redundancy. Experimental performance results show that our DNN model is more accurate in predicting crime occurrence than other prediction models.

  6. The covariability of North American land-atmosphere coupling strength and rainfall characteristics in reanalyses

    NASA Astrophysics Data System (ADS)

    Ferguson, C. R.; Roundy, J. K.; Kim, W.

    2016-12-01

    The GEWEX North American Regional Hydroclimate Project (RHP): Water for the Food Baskets of the World initiative is aimed at: improving understanding of key processes—both natural and anthropogenic—that determine water availability, improving understanding of the independent and collective sensitivity of these processes to local and global change, and the integration of knowledge gained into the next model development cycle for the benefit of improved water availability forecasts. Considering that the agricultural sector accounts for three quarters of water withdrawals and suffers the brunt of drought-related financial damages, a rational RHP focal point is subseasonal-to-seasonal forecast skill. Forecasts on this timescale over the Great Plains food basket have shown particular sensitivity to land initial conditions (i.e., soil moisture, snow cover, and vegetative stress) and the realism of modeled land-atmosphere (L-A) coupling. L-A coupling strength denotes the degree to which the model's land scheme (i.e., soil column memory and surface flux partitioning) affect the atmospheric forecast scheme's daytime evolution of the convective boundary layer, including cloud development and precipitation. Prior studies have connected L-A coupling strength to the phase and amplitude of the diurnal precipitation cycle, as well as the evolution of heatwaves and drought. In this study, we apply three metrics of L-A coupling strength: soil moisture memory, the two-legged coupling metric, and the convective triggering potential-humidity index, to the 161-year NOAA-Cooperative Institute for Research in Environmental Sciences Twentieth Century Reanalysis (20CRV2c). Over the full period, we also analyze warm-season rainfall characteristics and subsequently perform statistical trend and change point analyses on both sets of results. We test the stationarity of both coupling and rainfall characteristics as well as the hypothesis that any detected shifts in coupling strength and afternoon rainfall frequency will coincide. Although the source data has inherent limitations that will be quantified and discussed, the results will be the first of their kind over such a long period of record and will provide key insights for the North American RHP.

  7. A Modeling Approach for Evaluating the Coupled Riparian Vegetation-Geomorphic Response to Altered Flow Regimes

    NASA Astrophysics Data System (ADS)

    Manners, R.; Wilcox, A. C.; Merritt, D. M.

    2016-12-01

    The ecogeomorphic response of riparian ecosystems to a change in hydrologic properties is difficult to predict because of the interactions and feedbacks among plants, water, and sediment. Most riparian models of community dynamics assume a static channel, yet geomorphic processes strongly control the establishment and survival of riparian vegetation. Using a combination of approaches that includes empirical relationships and hydrodynamic models, we model the coupled vegetation-topographic response of three cross-sections on the Yampa and Green Rivers in Dinosaur National Monument, to a shift in the flow regime. The locations represent the variable geomorphology and vegetation composition of these canyon-bound rivers. We account for the inundation and hydraulic properties of vegetation plots surveyed over three years within International River Interface Cooperative (iRIC) Fastmech, equipped with a vegetation module that accounts for flexible stems and plant reconfiguration. The presence of functional groupings of plants, or those plants that respond similarly to environmental factors such as water availability and disturbance are determined from flow response curves developed for the Yampa River. Using field measurements of vegetation morphology, distance from the channel centerline, and dominant particle size and modeled inundation properties we develop an empirical relationship between these variables and topographic change. We evaluate vegetation and channel form changes over decadal timescales, allowing for the integration of processes over time. From our analyses, we identify thresholds in the flow regime that alter the distribution of plants and reduce geomorphic complexity, predominately through side-channel and backwater infilling. Simplification of some processes (e.g., empirically-derived sedimentation) and detailed treatment of others (e.g., plant-flow interactions) allows us to model the coupled dynamics of riparian ecosystems and evaluate the impact of small to large shifts in the flow regime. This approach will be useful to river managers and scientists, as they try to understand the potential changes to riparian ecosystems with uncertain changes to hydrologic regimes as a result of a changing climate and human demands.

  8. Thin layer chromatography coupled with surface-enhanced Raman scattering as a facile method for on-site quantitative monitoring of chemical reactions.

    PubMed

    Zhang, Zong-Mian; Liu, Jing-Fu; Liu, Rui; Sun, Jie-Fang; Wei, Guo-Hua

    2014-08-05

    By coupling surface-enhanced Raman spectroscopy (SERS) with thin layer chromatography (TLC), a facile and powerful method was developed for on-site monitoring the process of chemical reactions. Samples were preseparated on a TLC plate following a common TLC procedure, and then determined by SERS after fabricating a large-area, uniform SERS substrate on the TLC plate by spraying gold nanoparticles (AuNPs). Reproducible and strong SERS signals were obtained with substrates prepared by spraying 42-nm AuNPs at a density of 5.54 × 10(10) N/cm(2) on the TLC plate. The capacity of this TLC-SERS method was evaluated by monitoring a typical Suzuki coupling reaction of phenylboronic acid and 2-bromopyridine as a model. Results showed that this proposed method is able to identify reaction product that is invisible to the naked eye, and distinguish the reactant 2-bromopyridine and product 2-phenylpyridine, which showed almost the same retention factors (R(f)). Under the optimized conditions, the peak area of the characteristic Raman band (755 cm(-1)) of the product 2-phenylpyridine showed a good linear correlation with concentration in the range of 2-200 mg/L (R(2) = 0.9741), the estimated detection limit (1 mg/L 2-phenylpyridine) is much lower than the concentration of the chemicals in the common organic synthesis reaction system, and the product yield determined by the proposed TLC-SERS method agreed very well with that by UPLC-MS/MS. In addition, a new byproduct in the reaction system was found and identified through continuous Raman detection from the point of sample to the solvent front. This facile TLC-SERS method is quick, easy to handle, low-cost, sensitive, and can be exploited in on-site monitoring the processes of chemical reactions, as well as environmental and biological processes.

  9. Fostering Collaboration Across the U.S. Critical Zone Observatories Network

    NASA Astrophysics Data System (ADS)

    Sharkey, S.; White, T. S.

    2017-12-01

    The Critical Zone (CZ) is defined as the permeable layer from the top of the vegetation canopy to the bottom of freely circulating groundwater where rock, soil, water, air and life meet. The study of the CZ is motivated by an overall lack of understanding of the coupled physical, chemical, and biological processes in this zone at differing spatial and temporal scales. Critical Zone Observatories (CZOs), supported by the U.S. National Science Foundation's Geosciences Directorate, are natural laboratories that aim to provide infrastructure, data and models to gain understanding of the evolution and function of the CZ from grain-to-watershed scales. The nine U.S. observatories span a range of climatic, ecologic, geologic, and physiographic environments from California to Puerto Rico, working on site-specific hypotheses and network-scale goals. CZO research infrastructure allows for teams of cross-disciplinary scientists at each site to further CZ science using field and theoretical approaches, education and outreach, and cross-CZO science. Cross-CZO science emerges from a set of common CZ science questions and hypotheses focused on CZ structure and evolution, event-based and continuous fluxes across CZ interfaces, and changes in storage of major CZ reservoirs at the catchment scale. CZO research seeks to understand coupled processes across all timescales using quantitative models parameterized from observations of meteorological variables, streams, and groundwater, and sampling and analyzing landforms, bedrock, soils, and ecosystems. Each observatory strives to apply common infrastructure, protocols and measurements that help quantify the composition and fluxes of energy, water, solutes, sediments, energy, and mass across boundaries of the CZ system through both space and time. This type of approach enables researchers to access and integrate data in a way that allows for the isolation of environmental variables and comparison of processes and responses across environmental gradients. There is opportunity to foster cross-collaborations with existing research infrastructure (i.e. LTER, NEON, international CZOs) to promote cross-site science and expand upon geologic, climatic, ecological, land use and hydrologic gradients required to understand the CZ.

  10. UK Environmental Prediction - integration and evaluation at the convective scale

    NASA Astrophysics Data System (ADS)

    Lewis, Huw; Brunet, Gilbert; Harris, Chris; Best, Martin; Saulter, Andrew; Holt, Jason; Bricheno, Lucy; Brerton, Ashley; Reynard, Nick; Blyth, Eleanor; Martinez de la Torre, Alberto

    2015-04-01

    It has long been understood that accurate prediction and warning of the impacts of severe weather requires an integrated approach to forecasting. This was well demonstrated in the UK throughout winter 2013/14 when an exceptional run of severe winter storms, often with damaging high winds and intense rainfall led to significant damage from the large waves and storm surge along coastlines, and from saturated soils, high river flows and significant flooding inland. The substantial impacts on individuals, businesses and infrastructure indicate a pressing need to understand better the value that might be delivered through more integrated environmental prediction. To address this need, the Met Office, Centre for Ecology & Hydrology and National Oceanography Centre have begun to develop the foundations of a coupled high resolution probabilistic forecast system for the UK at km-scale. This links together existing model components of the atmosphere, coastal ocean, land surface and hydrology. Our initial focus on a 2-year Prototype project will demonstrate the UK coupled prediction concept in research mode, including an analysis of the winter 2013/14 storms and its impacts. By linking science development to operational collaborations such as the UK Natural Hazards Partnership, we can ensure that science priorities are rooted in user requirements. This presentation will provide an overview of UK environmental prediction activities and an update on progress during the first year of the Prototype project. We will present initial results from the coupled model development and discuss the challenges to realise the potential of integrated regional coupled forecasting for improving predictions and applications.

  11. Development of a social-hydrological-health framework for understanding risks of occurrence of diarrheal diseases

    NASA Astrophysics Data System (ADS)

    Khan, M. R. H.; Jutla, A.; Colwell, R. R.

    2015-12-01

    Diarrheal diseases continue to pose a severe health threat in regions where sanitation facilities remain marginal and are prone to destruction. With limited efficacy of vaccines, it is important to device alternate methods to determine environmental conditions favorable for diarrheal diseases. Several vibrios (V. cholerae., V. vulnificus, V. parahaemolyticus) have characteristic signatures that are associated with large scale climatic processes. The interactions of vibrios with humans eventually lead to outbreak of diseases. Here, using cholera as one of the signature diarrheal disease, we present a framework coupling social, hydrological and microbiological understanding with satellite remote sensing data to predict environmental conditions associated with outbreak of disease in several regions of sub-Saharan Africa. Hydroclimatic processes, primarily precipitation and temperature are found to be strongly associated with epidemic and episodic outbreak of cholera. We will present an algorithm to classify regions susceptible to risks of outbreak cholera using profile method in five epidemic regions of Mozambique, Central African Republic, Cameroon, South Sudan and Rwanda. Conditions for occurrence of cholera were detectable at least one month in advance. Using spatial land surface temperature (LST) data from satellites along with water accessibility data and population data, the implementation of the algorithm aid in classification of cholera risk regions.

  12. Leaf gas exchange of Andropogon gerardii Vitman, Panicum virgatum L., and Sorghastrum nutans (L.) Nash in a tallgrass prairie

    NASA Technical Reports Server (NTRS)

    Polley, H. W.; Norman, J. M.; Arkebauer, T. J.; Walter-Shea, E. A.; Greegor, D. H., Jr.; Bramer, B.

    1992-01-01

    Net CO2 assimilation as a function of internal CO2 and stomatal conductance to water vapor were measured on blades of the C4 grasses Andropogon gerardii Vitman, Panicum virgatrum L., and Sorghastrum nutans (L.) Nash in northeast Kansas over two growing seasons to determine the comparative physiological responses of these dominant grasses of the tallgrass prairie to environmental variables. The response of dark respiration to temperature and of net assimilation to CO2 concentration and absorbed quantum flux differed little among species. A. gerardii had lower potential photosynthetic rates at internal CO2 concentrations below saturation than P. virgatum and S. nutans, but net assimilation under ambient conditions was similar in the three species. Net assimilation and both the initial slope of assimilation versus internal CO2 curves and the maximum potential assimilation rate decreased as leaf water potential declined in blades of A. gerardii and S. nutans. Changes in assimilation capacity were paralleled by changes in stomatal conductance that were similar in all three species. The strong correlations among processes regulating leaf CO2 assimilation and transpiration in A. gerardii, P. virgatum, and S. nutans suggest that the processes are tightly and similarly coupled in these grasses over a wide range of environmental conditions encountered in the tallgrass prairie.

  13. Flow Reactor for studying Physicochemical and aging properties of SOA

    NASA Astrophysics Data System (ADS)

    Babar, Z. B.

    2016-12-01

    Secondary organic aerosols (SOA) have importance in environmental processes such as affecting earth's radiative balance and cloud formation processes. For studying SOA formation large scale environmental batch reactors and laboratory scale flow reactors have been used. In this study application of flow reactor to study physicochemical properties of SOA is also investigated after its characterization. The flow reactor is of cylindrical design (ID 15 cm x L 70 cm) equipped with UV lamps. It is coupled with various instruments such as scanning mobility particle sizer, NOx analyzer, ozone analyzer, VOC analyzer, hygrometer, and temperature sensors for gas and particle phase measurements. OH radicals were generated by custom build ozone generator and relative humidity. The following characterizations were performed: (1) residence time distribution (RTD) measurements, (2) RH and temperature control, (3) OH radical exposure range (atmospheric aging time), (4) gas phase oxidation of SOA precursors such as α-pinene by OH radical. The flow reactor yielded narrow RTDs. In particular, RH and temperature can be controlled effectively between 0-60% and 22-43oC, respectively. OH radical exposure ranges from 6.49x1010 to 3.68x1011 molecules/cm3s (0.49 to 4.91 days). Our initial efforts on OH radical generation using hydrogen peroxide and its quantification by using flourescenet technique will be also be presented.

  14. Sustainability of integrated land and water resources management in the face of climate and land use changes

    NASA Astrophysics Data System (ADS)

    Setegn, Shimelis

    2017-04-01

    Sustainable development integrates economic development, social development, and environmental protection. Land and Water resources are under severe pressure from increasing populations, fast development, deforestation, intensification of agriculture and the degrading environment in many part of the world. The demand for adequate and safe supplies of water is becoming crucial especially in the overpopulated urban centers of the Caribbean islands. Moreover, population growth coupled with environmental degradation and possible adverse impacts of land use and climate change are major factors limiting freshwater resource availability. The main objective of this study is to develop a hydrological model and analyze the spatiotemporal variability of hydrological processes in the Caribbean islands of Puerto Rico and Jamaica. Physically based eco-hydrological model was developed and calibrated in the Rio Grande Manati and Wag water watershed. Spatial distribution of annual hydrological processes, water balance components for wet and dry years, and annual hydrological water balance of the watershed are discussed. The impact of land use and climate change are addressed in the watersheds. Appropriate nature based adaptation strategies were evaluated. The study will present a good understanding of advantages and disadvantages of nature-based solutions for adapting climate change, hydro-meteorological risks and other extreme hydrological events.

  15. Development of an Intelligent Digital Watershed to understand water-human interaction for a sustainable Agroeconomy in Midwest USA

    NASA Astrophysics Data System (ADS)

    Mishra, S. K.; Rapolu, U.; Ding, D.; Muste, M.; Bennett, D.; Schnoor, J. L.

    2011-12-01

    Human activity is intricately linked to the quality and quantity of water resources. Although many studies have examined water-human interaction, the complexity of such coupled systems is not well understood largely because of gaps in our knowledge of water-cycle processes which are heavily influenced by socio-economic drivers. Considerable research has been performed to develop an understanding of the impact of local land use decisions on field and catchment processes at an annual basis. Still less is known about the impact of economic and environmental outcomes on decision-making processes at the local and national level. Traditional geographic information management systems lack the ability to support the modeling and analysis of complex spatial processes. New frameworks are needed to track, query, and analyze the massive amounts of data generated by ensembles of simulations produced by multiple models that couple socioeconomic and natural system processes. On this context, we propose to develop an Intelligent Digital Watershed (IDW) which fuses emerging concepts of Digital Watershed (DW). DW is a comprehensive characterization of the eco hydrologic systems based on the best available digital data generated by measurements and simulations models. Prototype IDW in the form of a cyber infrastructure based engineered system will facilitate novel insights into human/environment interactions through multi-disciplinary research focused on watershed-related processes at multiple spatio-temporal scales. In ongoing effort, the prototype IDW is applied to Clear Creek watershed, an agricultural dominating catchment in Iowa, to understand water-human processes relevant to management decisions by farmers regarding agro ecosystems. This paper would also lay out the database design that stores metadata about simulation scenarios, scenario inputs and outputs, and connections among these elements- essentially the database. The paper describes the cyber infrastructure and workflows developed for connecting the IDW modeling tools: ABM, Data-Driven Modeling, and SWAT.

  16. Facile synthesis of hierarchical Ag3PO4/TiO2 nanofiber heterostructures with highly enhanced visible light photocatalytic properties

    NASA Astrophysics Data System (ADS)

    Xie, Jinlei; Yang, Yefeng; He, Haiping; Cheng, Ding; Mao, Minmin; Jiang, Qinxu; Song, Lixin; Xiong, Jie

    2015-11-01

    Heterostructured semiconductor nanostructures have provoked great interest in the areas of energy, environment and catalysis. Herein, we report a novel hierarchical Ag3PO4/TiO2 heterostructure consisting of nearly spherical Ag3PO4 particles firmly coupled on the surface of TiO2 nanofibers (NFs). The construction of Ag3PO4/TiO2 heterostructure with tailored morphologies, compositions and optical properties was simply achieved via a facile and green synthetic strategy involving the electrospinning and solution-based processes. Owing to the synergetic effects of the components, the resulting hybrid heterostructures exhibited much improved visible light photocatalytic performance, which could degrade the RhB dye completely in 7.5 min. In addition, the coupling of Ag3PO4 particles with UV-light-sensitive TiO2 NFs enabled full utilization of solar energy and less consumption of noble metals, significantly appealing for their practical use in new energy sources and environmental issues. The developed synthetic strategy was considered to be applicable for the rational design and construction of other heterostructured catalysts.

  17. Influence of methane addition on selenium isotope sensitivity and their spectral interferences.

    PubMed

    Floor, Geerke H; Millot, Romain; Iglesias, Mónica; Négrel, Philippe

    2011-02-01

    The measurements of stable selenium (Se) isotopic signatures by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) are very challenging, due to the presence of spectral interferences and the low abundance of Se in environmental samples. We systematically investigated the effect of methane addition on the signal of Se isotopes and their interferences. It is the first time that the effect of methane addition has been assessed for all Se isotopes and its potential interferences using hydride generator multi-collector inductively coupled plasma mass spectrometry (HG-MC-ICP-MS). Our results show that a small methane addition increases the sensitivity. However, the response differs between a hydride generator and a standard introduction system, which might be related to differences in the ionization processes. Both argon and hydrogen-based interferences, the most common spectral interferences on selenium isotopes in HG-MC-ICP-MS, decrease with increasing methane addition. Therefore, analyte-interference ratios and precision are improved. Methane addition has thus a high potential for the application to stable Se isotopes ratios by HG-MC-ICP-MS. Copyright © 2011 John Wiley & Sons, Ltd.

  18. Coupling Solar Energy into Reactions: Materials Design for Surface Plasmon-Mediated Catalysis.

    PubMed

    Long, Ran; Li, Yu; Song, Li; Xiong, Yujie

    2015-08-26

    Enabled by surface plasmons, noble metal nanostructures can interact with and harvest incident light. As such, they may serve as unique media to generate heat, supply energetic electrons, and provide strong local electromagnetic fields for chemical reactions through different mechanisms. This solar-to-chemical pathway provides a new approach to solar energy utilization, alternative to conventional semiconductor-based photocatalysis. To provide readers with a clear picture of this newly recognized process, this review presents coupling solar energy into chemical reactions through plasmonic nanostructures. It starts with a brief introduction of surface plasmons in metallic nanostructures, followed by a demonstration of tuning plasmonic features by tailoring their physical parameters. Owing to their tunable plasmonic properties, metallic materials offer a platform to trigger and drive chemical reactions at the nanoscale, as systematically overviewed in this article. The design rules for plasmonic materials for catalytic applications are further outlined based on existing examples. At the end of this article, the challenges and opportunities for further development of plasmonic-mediated catalysis toward energy and environmental applications are discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Interrogating the catalytic mechanism of nanoparticle mediated Stille coupling reactions employing bio-inspired Pd nanocatalysts.

    PubMed

    Pacardo, Dennis B; Slocik, Joseph M; Kirk, Kyle C; Naik, Rajesh R; Knecht, Marc R

    2011-05-01

    To address issues concerning the global environmental and energy state, new catalytic technologies must be developed that translate ambient and efficient conditions to heavily used reactions. To achieve this, the structure/function relationship between model catalysts and individual reactions must be critically discerned to identify structural motifs responsible for the reactivity. This is especially true for nanoparticle-based systems where this level of information remains limited. Here we present evidence indicating that peptide-capped Pd nanoparticles drive Stille C-C coupling reactions via Pd atom leaching. Through a series of reaction studies, the materials are shown to be optimized for reactivity under ambient conditions where increases in temperature or catalyst concentration deactivate reactivity due to the leaching process. A quartz crystal microbalance analysis demonstrates that Pd leaching occurs during the initial oxidative addition step at the nanoparticle surface by aryl halides. Together, this suggests that peptide-based materials may be optimally suited for use as model systems to isolate structural motifs responsible for the generation of catalytically reactive materials under ambient synthetic conditions. © The Royal Society of Chemistry 2011

  20. Interrogating the catalytic mechanism of nanoparticle mediated Stille coupling reactions employing bio-inspired Pd nanocatalysts

    NASA Astrophysics Data System (ADS)

    Pacardo, Dennis B.; Slocik, Joseph M.; Kirk, Kyle C.; Naik, Rajesh R.; Knecht, Marc R.

    2011-05-01

    To address issues concerning the global environmental and energy state, new catalytic technologies must be developed that translate ambient and efficient conditions to heavily used reactions. To achieve this, the structure/function relationship between model catalysts and individual reactions must be critically discerned to identify structural motifs responsible for the reactivity. This is especially true for nanoparticle-based systems where this level of information remains limited. Here we present evidence indicating that peptide-capped Pd nanoparticles drive Stille C-C coupling reactions via Pd atom leaching. Through a series of reaction studies, the materials are shown to be optimized for reactivity under ambient conditions where increases in temperature or catalyst concentration deactivate reactivity due to the leaching process. A quartz crystal microbalance analysis demonstrates that Pd leaching occurs during the initial oxidative addition step at the nanoparticle surface by aryl halides. Together, this suggests that peptide-based materials may be optimally suited for use as model systems to isolate structural motifs responsible for the generation of catalytically reactive materials under ambient synthetic conditions.

  1. Coupled turbulence and aerosol dynamics modeling of vehicle exhaust plumes using the CTAG model

    NASA Astrophysics Data System (ADS)

    Wang, Yan Jason; Zhang, K. Max

    2012-11-01

    This paper presents the development and evaluation of an environmental turbulent reacting flow model, the Comprehensive Turbulent Aerosol Dynamics and Gas Chemistry (CTAG) model. CTAG is designed to simulate transport and transformation of multiple air pollutants, e.g., from emission sources to ambient background. For the on-road and near-road applications, CTAG explicitly couples the major turbulent mixing processes, i.e., vehicle-induced turbulence (VIT), road-induced turbulence (RIT) and atmospheric boundary layer turbulence with gas-phase chemistry and aerosol dynamics. CTAG's transport model is referred to as CFD-VIT-RIT. This paper presents the evaluation of the CTAG model in simulating the dynamics of individual plumes in the “tailpipe-to-road” stage, i.e., VIT behind a moving van and aerosol dynamics in the wake of a diesel car by comparing the modeling results against the respective field measurements. Combined with sensitivity studies, we analyze the relative roles of VIT, sulfuric acid induced nucleation, condensation of organic compounds and presence of soot-mode particles in capturing the dynamics of exhaust plumes as well as their implications in vehicle emission controls.

  2. Coupling between populations of copepod taxa within an estuarine ecosystem and the adjacent offshore regions

    NASA Astrophysics Data System (ADS)

    McGinty, N.; Johnson, M. P.; Power, A. M.

    2012-07-01

    Population dynamics in open systems are complicated by the interactions of local demography and local environmental forcing with processes occurring at larger scales. A local system such as an estuary or bay may contain a zooplankton population that effectively becomes independent of regional dynamics or the local dynamics may be closely coupled to a broader scale pattern. As an alternative, the details of migration and advection may mean that dynamics in a local system are coupled to other specific areas rather than tracking the overall dynamics at a larger scale. We used a reconstructed time series (1973-1987) for copepod taxa to examine the extent to which zooplankton dynamics in Galway Bay reflect processes in broader areas of the NE Atlantic. Continuous Plankton Recorder (CPR) counts were used to establish time series for nine offshore ecoregions, with the regions themselves defined using underlying patterns of chlorophyll variability. The open nature of Galway Bay was reflected in strong associations between bay zooplankton counts and offshore CPR data in a majority of cases (7/10). For each zooplankton taxon, there were large differences among regions in the degree of association with Galway Bay time series. Akaike weights indicated that one ecoregion tended to be the dominant link for each taxon. This indicates that the zooplankton of the Bay reflect more than the local modification of a regional signal and that different zooplankton in the bay may have separate source regions. The data from Galway Bay also fall within a 'sampling shadow' of the CPR. Later years of the time series showed evidence for changes in phenology, with spring zooplankton peaks generally occurring earlier in the year for smaller species.

  3. Phytoremediation: An Environmentally Sound Technology for Pollution Prevention, Control and Remediation in Developing Countries

    ERIC Educational Resources Information Center

    Erakhrumen, Andrew Agbontalor

    2007-01-01

    The problem of environmental pollution has assumed an unprecedented proportion in many parts of the world especially in Nigeria and its Niger-Delta region in particular. This region is bedeviled with this problem perhaps owing to interplay of demographic and socio-economic forces coupled with the various activities that revolve round the…

  4. Detection and Quantification of Silver Nanoparticles at Environmentally Relevant Concentrations Using Asymmetric Flow Field–Flow Fractionation Online with Single Particle Inductively Coupled Plasma Mass Spectrometry

    EPA Science Inventory

    The presence of silver nanoparticles (AgNPs) in aquatic environments could potentially cause adverse impacts on ecosystems and human health. However, current understanding of the environmental fate and transport of AgNPs is still limited because their properties in complex enviro...

  5. Model coupling intraparticle diffusion/sorption, nonlinear sorption, and biodegradation processes

    USGS Publications Warehouse

    Karapanagioti, Hrissi K.; Gossard, Chris M.; Strevett, Keith A.; Kolar, Randall L.; Sabatini, David A.

    2001-01-01

    Diffusion, sorption and biodegradation are key processes impacting the efficiency of natural attenuation. While each process has been studied individually, limited information exists on the kinetic coupling of these processes. In this paper, a model is presented that couples nonlinear and nonequilibrium sorption (intraparticle diffusion) with biodegradation kinetics. Initially, these processes are studied independently (i.e., intraparticle diffusion, nonlinear sorption and biodegradation), with appropriate parameters determined from these independent studies. Then, the coupled processes are studied, with an initial data set used to determine biodegradation constants that were subsequently used to successfully predict the behavior of a second data set. The validated model is then used to conduct a sensitivity analysis, which reveals conditions where biodegradation becomes desorption rate-limited. If the chemical is not pre-equilibrated with the soil prior to the onset of biodegradation, then fast sorption will reduce aqueous concentrations and thus biodegradation rates. Another sensitivity analysis demonstrates the importance of including nonlinear sorption in a coupled diffusion/sorption and biodegradation model. While predictions based on linear sorption isotherms agree well with solution concentrations, for the conditions evaluated this approach overestimates the percentage of contaminant biodegraded by as much as 50%. This research demonstrates that nonlinear sorption should be coupled with diffusion/sorption and biodegradation models in order to accurately predict bioremediation and natural attenuation processes. To our knowledge this study is unique in studying nonlinear sorption coupled with intraparticle diffusion and biodegradation kinetics with natural media.

  6. Spatiotemporal Variation in Environmental Vibrio cholerae in an Estuary in Southern Coastal Ecuador.

    PubMed

    Ryan, Sadie J; Stewart-Ibarra, Anna M; Ordóñez-Enireb, Eunice; Chu, Winnie; Finkelstein, Julia L; King, Christine A; Escobar, Luis E; Lupone, Christina; Heras, Froilan; Tauzer, Erica; Waggoner, Egan; James, Tyler G; Cárdenas, Washington B; Polhemus, Mark

    2018-03-10

    Cholera emergence is strongly linked to local environmental and ecological context. The 1991-2004 pandemic emerged in Perú and spread north into Ecuador's El Oro province, making this a key site for potential re-emergence. Machala, El Oro, is a port city of 250,000 inhabitants, near the Peruvian border. Many livelihoods depend on the estuarine system, from fishing for subsistence and trade, to domestic water use. In 2014, we conducted biweekly sampling for 10 months in five estuarine locations, across a gradient of human use, and ranging from inland to ocean. We measured water-specific environmental variables implicated in cholera growth and persistence: pH, temperature, salinity, and algal concentration, and evaluated samples in five months for pathogenic and non-pathogenic Vibrio cholerae , by polymerase chain reaction (PCR). We found environmental persistence of pandemic strains O1 and O139, but no evidence for toxigenic strains. Vibrio cholerae presence was coupled to algal and salinity concentration, and sites exhibited considerable seasonal and spatial heterogeneity. This study indicates that environmental conditions in Machala are optimal for cholera re-emergence, with risk peaking during September, and higher risk near urban periphery low-income communities. This highlights a need for surveillance of this coupled cholera-estuarine system to anticipate potential future cholera outbreaks.

  7. Spatiotemporal Variation in Environmental Vibrio cholerae in an Estuary in Southern Coastal Ecuador

    PubMed Central

    Stewart-Ibarra, Anna M.; Ordóñez-Enireb, Eunice; Chu, Winnie; Finkelstein, Julia L.; King, Christine A.; Escobar, Luis E.; Lupone, Christina; Heras, Froilan; Tauzer, Erica; Waggoner, Egan; Polhemus, Mark

    2018-01-01

    Cholera emergence is strongly linked to local environmental and ecological context. The 1991–2004 pandemic emerged in Perú and spread north into Ecuador’s El Oro province, making this a key site for potential re-emergence. Machala, El Oro, is a port city of 250,000 inhabitants, near the Peruvian border. Many livelihoods depend on the estuarine system, from fishing for subsistence and trade, to domestic water use. In 2014, we conducted biweekly sampling for 10 months in five estuarine locations, across a gradient of human use, and ranging from inland to ocean. We measured water-specific environmental variables implicated in cholera growth and persistence: pH, temperature, salinity, and algal concentration, and evaluated samples in five months for pathogenic and non-pathogenic Vibrio cholerae, by polymerase chain reaction (PCR). We found environmental persistence of pandemic strains O1 and O139, but no evidence for toxigenic strains. Vibrio cholerae presence was coupled to algal and salinity concentration, and sites exhibited considerable seasonal and spatial heterogeneity. This study indicates that environmental conditions in Machala are optimal for cholera re-emergence, with risk peaking during September, and higher risk near urban periphery low-income communities. This highlights a need for surveillance of this coupled cholera–estuarine system to anticipate potential future cholera outbreaks. PMID:29534431

  8. Crossing the Barriers: An Analysis of Land Access Barriers to Geothermal Development and Potential Improvement Scenarios

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levine, Aaron L; Young, Katherine R

    Developers have identified many non-technical barriers to geothermal power development, including access to land. Activities required for accessing land, such as environmental review and private and public leasing can take a considerable amount of time and can delay or prevent project development. This paper discusses the impacts to available geothermal resources and deployment caused by land access challenges, including tribal and cultural resources, environmentally sensitive areas, biological resources, land ownership, federal and state lease queues, and proximity to military installations. In this analysis, we identified challenges that have the potential to prevent development of identified and undiscovered hydrothermal geothermal resources.more » We found that an estimated 400 MW of identified geothermal resource potential and 4,000 MW of undiscovered geothermal resource potential were either unallowed for development or contained one or more significant barriers that could prevent development at the site. Potential improvement scenarios that could be employed to overcome these barriers include (1) providing continuous funding to the U.S. Forest Service (USFS) for processing geothermal leases and permit applications and (2) the creation of advanced environmental mitigation measures. The model results forecast that continuous funding to the USFS could result in deployment of an additional 80 MW of geothermal capacity by 2030 and 124 MW of geothermal capacity by 2050 when compared to the business-as-usual scenario. The creation of advanced environmental mitigation measures coupled with continuous funding to the USFS could result in deployment of an additional 97 MW of geothermal capacity by 2030 and 152 MW of geothermal capacity by 2050 when compared to the business-as-usual scenario. The small impact on potential deployment in these improvement scenarios suggests that these 4,400 MW have other barriers to development in addition to land access. In other words, simply making more resources available for development does not increase deployment; however, impacts to deployment could increase when coupled with other improvements (e.g., permitting, market and/or technology improvements).« less

  9. Adjoint of the global Eulerian-Lagrangian coupled atmospheric transport model (A-GELCA v1.0): development and validation

    NASA Astrophysics Data System (ADS)

    Belikov, Dmitry A.; Maksyutov, Shamil; Yaremchuk, Alexey; Ganshin, Alexander; Kaminski, Thomas; Blessing, Simon; Sasakawa, Motoki; Gomez-Pelaez, Angel J.; Starchenko, Alexander

    2016-02-01

    We present the development of the Adjoint of the Global Eulerian-Lagrangian Coupled Atmospheric (A-GELCA) model that consists of the National Institute for Environmental Studies (NIES) model as an Eulerian three-dimensional transport model (TM), and FLEXPART (FLEXible PARTicle dispersion model) as the Lagrangian Particle Dispersion Model (LPDM). The forward tangent linear and adjoint components of the Eulerian model were constructed directly from the original NIES TM code using an automatic differentiation tool known as TAF (Transformation of Algorithms in Fortran; http://www.FastOpt.com, with additional manual pre- and post-processing aimed at improving transparency and clarity of the code and optimizing the performance of the computing, including MPI (Message Passing Interface). The Lagrangian component did not require any code modification, as LPDMs are self-adjoint and track a significant number of particles backward in time in order to calculate the sensitivity of the observations to the neighboring emission areas. The constructed Eulerian adjoint was coupled with the Lagrangian component at a time boundary in the global domain. The simulations presented in this work were performed using the A-GELCA model in forward and adjoint modes. The forward simulation shows that the coupled model improves reproduction of the seasonal cycle and short-term variability of CO2. Mean bias and standard deviation for five of the six Siberian sites considered decrease roughly by 1 ppm when using the coupled model. The adjoint of the Eulerian model was shown, through several numerical tests, to be very accurate (within machine epsilon with mismatch around to ±6 e-14) compared to direct forward sensitivity calculations. The developed adjoint of the coupled model combines the flux conservation and stability of an Eulerian discrete adjoint formulation with the flexibility, accuracy, and high resolution of a Lagrangian backward trajectory formulation. A-GELCA will be incorporated into a variational inversion system designed to optimize surface fluxes of greenhouse gases.

  10. Earth observation for regional scale environmental and natural resources management

    NASA Astrophysics Data System (ADS)

    Bernknopf, R.; Brookshire, D.; Faulkner, S.; Chivoiu, B.; Bridge, B.; Broadbent, C.

    2013-12-01

    Earth observations (EO) provide critical information to natural resource assessment. Three examples are presented: conserving potable groundwater in intense agricultural regions, maximizing ecosystem service benefits at regional scales from afforestation investment and management, and enabling integrated natural and behavioral sciences for resource management and policy analysis. In each of these cases EO of different resolutions are used in different ways to help in the classification, characterization, and availability of natural resources and ecosystem services. To inform decisions, each example includes a spatiotemporal economic model to optimize the net societal benefits of resource development and exploitation. 1) EO is used for monitoring land use in intensively cultivated agricultural regions. Archival imagery is coupled to a hydrogeological process model to evaluate the tradeoff between agrochemical use and retention of potable groundwater. EO is used to couple individual producers and regional resource managers using information from markets and natural systems to aid in the objective of maximizing agricultural production and maintaining groundwater quality. The contribution of EO is input to a nitrate loading and transport model to estimate the cumulative impact on groundwater at specified distances from specific sites (wells) for 35 Iowa counties and two aquifers. 2) Land use/land cover (LULC) derived from EO is used to compare biological carbon sequestration alternatives and their provisioning of ecosystem services. EO is used to target land attributes that are more or less desirable for enhancing ecosystem services in two parishes in Louisiana. Ecological production functions are coupled with value data to maximize the expected return on investment in carbon sequestration and other ancillary ecosystem services while minimizing the risk. 3) Environmental and natural resources management decisions employ probabilistic estimates of yet-to-find or yet-to-develop volumes of natural and environmental resources and ecosystem services. The potential quantities of resources available are of great societal relevance, as are the resources that are necessarily disturbed in the development of economic reserves. EO is input to a multidimensional decision framework for natural resources and ecosystem services. Imagery supports a spatiotemporal model of regional resource extraction and the associated impacts on ecosystem services. The framework is used to assess societal tradeoffs by evaluating the benefits and costs of future development or preservation in a comparison of regional development options.

  11. In-depth investigation of spin-on doped solar cells with thermally grown oxide passivation

    NASA Astrophysics Data System (ADS)

    Ahmad, Samir Mahmmod; Cheow, Siu Leong; Ludin, Norasikin A.; Sopian, K.; Zaidi, Saleem H.

    Solar cell industrial manufacturing, based largely on proven semiconductor processing technologies supported by significant advancements in automation, has reached a plateau in terms of cost and efficiency. However, solar cell manufacturing cost (dollar/watt) is still substantially higher than fossil fuels. The route to lowering cost may not lie with continuing automation and economies of scale. Alternate fabrication processes with lower cost and environmental-sustainability coupled with self-reliance, simplicity, and affordability may lead to price compatibility with carbon-based fuels. In this paper, a custom-designed formulation of phosphoric acid has been investigated, for n-type doping in p-type substrates, as a function of concentration and drive-in temperature. For post-diffusion surface passivation and anti-reflection, thermally-grown oxide films in 50-150-nm thickness were grown. These fabrication methods facilitate process simplicity, reduced costs, and environmental sustainability by elimination of poisonous chemicals and toxic gases (POCl3, SiH4, NH3). Simultaneous fire-through contact formation process based on screen-printed front surface Ag and back surface through thermally grown oxide films was optimized as a function of the peak temperature in conveyor belt furnace. Highest efficiency solar cells fabricated exhibited efficiency of ∼13%. Analysis of results based on internal quantum efficiency and minority carried measurements reveals three contributing factors: high front surface recombination, low minority carrier lifetime, and higher reflection. Solar cell simulations based on PC1D showed that, with improved passivation, lower reflection, and high lifetimes, efficiency can be enhanced to match with commercially-produced PECVD SiN-coated solar cells.

  12. Northeast Artificial Intelligence Consortium (NAIC). Volume 15. Strategies for Coupling Symbolic and Numerical Computation in Knowledge Base Systems

    DTIC Science & Technology

    1990-12-01

    Implementation of Coupled System 18 15.4. CASE STUDIES & IMPLEMENTATION EXAMPLES 24 15.4.1. The Case Studies of Coupled System 24 15.4.2. Example: Coupled System...occurs during specific phases of the problem-solving process. By decomposing the coupling process into its component layers we effectively study the nature...by the qualitative model, appropriate mathematical model is invoked. 5) The results are verified. If successful, stop. Else go to (2) and use an

  13. Coupling Computer-Aided Process Simulation and ...

    EPA Pesticide Factsheets

    A methodology is described for developing a gate-to-gate life cycle inventory (LCI) of a chemical manufacturing process to support the application of life cycle assessment in the design and regulation of sustainable chemicals. The inventories were derived by first applying process design and simulation of develop a process flow diagram describing the energy and basic material flows of the system. Additional techniques developed by the U.S. Environmental Protection Agency for estimating uncontrolled emissions from chemical processing equipment were then applied to obtain a detailed emission profile for the process. Finally, land use for the process was estimated using a simple sizing model. The methodology was applied to a case study of acetic acid production based on the Cativa tm process. The results reveal improvements in the qualitative LCI for acetic acid production compared to commonly used databases and top-down methodologies. The modeling techniques improve the quantitative LCI results for inputs and uncontrolled emissions. With provisions for applying appropriate emission controls, the proposed method can provide an estimate of the LCI that can be used for subsequent life cycle assessments. As part of its mission, the Agency is tasked with overseeing the use of chemicals in commerce. This can include consideration of a chemical's potential impact on health and safety, resource conservation, clean air and climate change, clean water, and sustainable

  14. Effect of interface reaction and diffusion on stress-oxidation coupling at high temperature

    NASA Astrophysics Data System (ADS)

    Yue, Mengkun; Dong, Xuelin; Fang, Xufei; Feng, Xue

    2018-04-01

    High-temperature structural materials undergo oxidation during the service, and stress would generate in the oxide film. Understanding the coupling effect between stress and oxidation contributes to the understanding of material degradation and failure during the oxidation process. Here, we propose a model to investigative the coupling effect of stress and oxidation at high temperature by considering the three-stage oxidation process, where both the interface reaction and the diffusion process are present. The governing equations including the oxidation kinetics and stress equilibrium for isothermal oxidation under stress-oxidation coupling effect have been derived. The theory is validated by comparing with the experimental results of SiO2 grown on Si substrate. Results show that the coupling of stress and oxidation influences the growth of the oxide film by affecting all three stages of the oxidation process.

  15. The construction of a model of the process of couples' forgiveness in emotion-focused therapy for couples.

    PubMed

    Meneses, Catalina Woldarsky; Greenberg, Leslie S

    2011-10-01

    This study explored how forgiveness unfolds in the context of emotion-focused couples therapy (EFT-C) in eight cases of women betrayed by their partners. Forgiveness was defined as a process involving the reduction in negative feelings and the giving out of undeserved compassion. This was measured by changes in the pre- and posttreatment scores on the Enright Forgiveness Inventory, the Unfinished Business Resolution Scale, and a single item directly asking respondents to indicate their degree of forgiveness. A task analysis was performed to rigorously track the steps leading to forgiveness using videotapes of therapy sessions for eight couples. The performance of the four couples who forgave were compared with each other and then contrasted with the performance of another four couples who did not reach forgiveness at the end of therapy. Based on these observations, a model of the process of forgiveness in EFT-C and a process rating system were developed. © 2011 American Association for Marriage and Family Therapy.

  16. Female Couples Undergoing IVF with Partner Eggs (Co-IVF): Pathways to Parenthood.

    PubMed

    Yeshua, Arielle; Lee, Joseph A; Witkin, Georgia; Copperman, Alan B

    2015-06-01

    Egg sharing in female couples can be used to allow dual participation of female couples in the pregnancy process. The oocyte donor-partner provides the eggs and the recipient partner provides the uterine environment for gestation. We present descriptive data of our experience in female couples to establish a better understanding of utilization of co-in vitro fertilization (Co-IVF) for social and medical reasons. Female couples enrolled in a third party reproduction program that engaged in at least one Co-IVF cycle were included. Previous assisted reproductive technology (ART) cycle data, Co-IVF cycle information and pregnancy outcomes were evaluated. Female couples (n=21) who participated in Co-IVF cycles were analyzed. Over time, 16/21 (76%) of couples achieved at least one pregnancy, 9 (42%) couples delivered, and there are another 5 (23%) ongoing pregnancies. Our analysis presents descriptive data and sheds realistic expectations for Co-IVF couples. Co-IVF cycles can result in a shared experience with regard to the process of creating a family, while preserving a female couple's desire for dual partner participation in the gestational process. We encourage centers treating female couples to consider departing from traditional nomenclature of "donors" and "recipients" and adopting the nomenclature "Co-IVF" to describe the modern understanding of the shared experience. Even if female couples have experienced prior unsuccessful cycles, couples ultimately retain an excellent prognosis for reproductive success using Co-IVF.

  17. Temporal and Spatial Variation in Peatland Carbon Cycling and Implications for Interpreting Responses of an Ecosystem-Scale Warming Experiment

    DOE PAGES

    Griffiths, Natalie A.; Hanson, Paul J.; Ricciuto, Daniel M.; ...

    2017-11-22

    Here, we are conducting a large-scale, long-term climate change response experiment in an ombrotrophic peat bog in Minnesota to evaluate the effects of warming and elevated CO 2 on ecosystem processes using empirical and modeling approaches. To better frame future assessments of peatland responses to climate change, we characterized and compared spatial vs. temporal variation in measured C cycle processes and their environmental drivers. We also conducted a sensitivity analysis of a peatland C model to identify how variation in ecosystem parameters contributes to model prediction uncertainty. High spatial variability in C cycle processes resulted in the inability to determinemore » if the bog was a C source or sink, as the 95% confidence interval ranged from a source of 50 g C m –2 yr –1 to a sink of 67 g C m –2 yr –1. Model sensitivity analysis also identified that spatial variation in tree and shrub photosynthesis, allocation characteristics, and maintenance respiration all contributed to large variations in the pretreatment estimates of net C balance. Variation in ecosystem processes can be more thoroughly characterized if more measurements are collected for parameters that are highly variable over space and time, and especially if those measurements encompass environmental gradients that may be driving the spatial and temporal variation (e.g., hummock vs. hollow microtopographies, and wet vs. dry years). Together, the coupled modeling and empirical approaches indicate that variability in C cycle processes and their drivers must be taken into account when interpreting the significance of experimental warming and elevated CO 2 treatments.« less

  18. Temporal and Spatial Variation in Peatland Carbon Cycling and Implications for Interpreting Responses of an Ecosystem-Scale Warming Experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Griffiths, Natalie A.; Hanson, Paul J.; Ricciuto, Daniel M.

    Here, we are conducting a large-scale, long-term climate change response experiment in an ombrotrophic peat bog in Minnesota to evaluate the effects of warming and elevated CO 2 on ecosystem processes using empirical and modeling approaches. To better frame future assessments of peatland responses to climate change, we characterized and compared spatial vs. temporal variation in measured C cycle processes and their environmental drivers. We also conducted a sensitivity analysis of a peatland C model to identify how variation in ecosystem parameters contributes to model prediction uncertainty. High spatial variability in C cycle processes resulted in the inability to determinemore » if the bog was a C source or sink, as the 95% confidence interval ranged from a source of 50 g C m –2 yr –1 to a sink of 67 g C m –2 yr –1. Model sensitivity analysis also identified that spatial variation in tree and shrub photosynthesis, allocation characteristics, and maintenance respiration all contributed to large variations in the pretreatment estimates of net C balance. Variation in ecosystem processes can be more thoroughly characterized if more measurements are collected for parameters that are highly variable over space and time, and especially if those measurements encompass environmental gradients that may be driving the spatial and temporal variation (e.g., hummock vs. hollow microtopographies, and wet vs. dry years). Together, the coupled modeling and empirical approaches indicate that variability in C cycle processes and their drivers must be taken into account when interpreting the significance of experimental warming and elevated CO 2 treatments.« less

  19. Description and verification of a U.S. Naval Research Lab's loosely coupled data assimilation system for the Navy's Earth System Model

    NASA Astrophysics Data System (ADS)

    Barton, N. P.; Metzger, E. J.; Smedstad, O. M.; Ruston, B. C.; Wallcraft, A. J.; Whitcomb, T.; Ridout, J. A.; Zamudio, L.; Posey, P.; Reynolds, C. A.; Richman, J. G.; Phelps, M.

    2017-12-01

    The Naval Research Laboratory is developing an Earth System Model (NESM) to provide global environmental information to meet Navy and Department of Defense (DoD) operations and planning needs from the upper atmosphere to under the sea. This system consists of a global atmosphere, ocean, ice, wave, and land prediction models and the individual models include: atmosphere - NAVy Global Environmental Model (NAVGEM); ocean - HYbrid Coordinate Ocean Model (HYCOM); sea ice - Community Ice CodE (CICE); WAVEWATCH III™; and land - NAVGEM Land Surface Model (LSM). Data assimilation is currently loosely coupled between the atmosphere component using a 6-hour update cycle in the Naval Research Laboratory (NRL) Atmospheric Variational Data Assimilation System - Accelerated Representer (NAVDAS-AR) and the ocean/ice components using a 24-hour update cycle in the Navy Coupled Ocean Data Assimilation (NCODA) with 3 hours of incremental updating. This presentation will describe the US Navy's coupled forecast model, the loosely coupled data assimilation, and compare results against stand-alone atmosphere and ocean/ice models. In particular, we will focus on the unique aspects of this modeling system, which includes an eddy resolving ocean model and challenges associated with different update-windows and solvers for the data assimilation in the atmosphere and ocean. Results will focus on typical operational diagnostics for atmosphere, ocean, and ice analyses including 500 hPa atmospheric height anomalies, low-level winds, temperature/salinity ocean depth profiles, ocean acoustical proxies, sea ice edge, and sea ice drift. Overall, the global coupled system is performing with comparable skill to the stand-alone systems.

  20. Gestural coupling and social cognition: Möbius Syndrome as a case study

    PubMed Central

    Krueger, Joel; Michael, John

    2012-01-01

    Social cognition researchers have become increasingly interested in the ways that behavioral, physiological, and neural coupling facilitate social interaction and interpersonal understanding. We distinguish two ways of conceptualizing the role of such coupling processes in social cognition: strong and moderate interactionism. According to strong interactionism (SI), low-level coupling processes are alternatives to higher-level individual cognitive processes; the former at least sometimes render the latter superfluous. Moderate interactionism (MI) on the other hand, is an integrative approach. Its guiding assumption is that higher-level cognitive processes are likely to have been shaped by the need to coordinate, modulate, and extract information from low-level coupling processes. In this paper, we present a case study on Möbius Syndrome (MS) in order to contrast SI and MI. We show how MS—a form of congenital bilateral facial paralysis—can be a fruitful source of insight for research exploring the relation between high-level cognition and low-level coupling. Lacking a capacity for facial expression, individuals with MS are deprived of a primary channel for gestural coupling. According to SI, they lack an essential enabling feature for social interaction and interpersonal understanding more generally and thus ought to exhibit severe deficits in these areas. We challenge SI's prediction and show how MS cases offer compelling reasons for instead adopting MI's pluralistic model of social interaction and interpersonal understanding. We conclude that investigations of coupling processes within social interaction should inform rather than marginalize or eliminate investigation of higher-level individual cognition. PMID:22514529

  1. Investigating redox processes under diffusive and advective flow conditions using a coupled omics and synchrotron approach

    NASA Astrophysics Data System (ADS)

    Kemner, K. M.; Boyanov, M.; Flynn, T. M.; O'Loughlin, E. J.; Antonopoulos, D. A.; Kelly, S.; Skinner, K.; Mishra, B.; Brooks, S. C.; Watson, D. B.; Wu, W. M.

    2015-12-01

    FeIII- and SO42--reducing microorganisms and the mineral phases they produce have profound implications for many processes in aquatic and terrestrial systems. In addition, many of these microbially-catalysed geochemical transformations are highly dependent upon introduction of reactants via advective and diffusive hydrological transport. We have characterized microbial communities from a set of static microcosms to test the effect of ethanol diffusion and sulfate concentration on UVI-contaminated sediment. The spatial distribution, valence states, and speciation of both U and Fe were monitored in situ throughout the experiment by synchrotron x-ray absorption spectroscopy, in parallel with solution measurements of pH and the concentrations of sulfate, ethanol, and organic acids. After reaction initiation, a ~1-cm thick layer of sediment near the sediment-water (S-W) interface became visibly dark. Fe XANES spectra of the layer were consistent with the formation of FeS. Over the 4 year duration of the experiment, U LIII-edge XANES indicated reduction of U, first in the dark layer and then throughout the sediment. Next, the microcosms were disassembled and samples were taken from the overlying water and different sediment regions. We extracted DNA and characterized the microbial community by sequencing 16S rRNA gene amplicons with the Illumina MiSeq platform and found that the community evolved from its originally homogeneous composition, becoming significantly spatially heterogeneous. We have also developed an x-ray accessible column to probe elemental transformations as they occur along the flow path in a porous medium with the purpose of refining reactive transport models (RTMs) that describe coupled physical and biogeochemical processes in environmental systems. The elemental distribution dynamics and the RTMs of the redox driven processes within them will be presented.

  2. Coupled Multi-physical Simulations for the Assessment of Nuclear Waste Repository Concepts: Modeling, Software Development and Simulation

    NASA Astrophysics Data System (ADS)

    Massmann, J.; Nagel, T.; Bilke, L.; Böttcher, N.; Heusermann, S.; Fischer, T.; Kumar, V.; Schäfers, A.; Shao, H.; Vogel, P.; Wang, W.; Watanabe, N.; Ziefle, G.; Kolditz, O.

    2016-12-01

    As part of the German site selection process for a high-level nuclear waste repository, different repository concepts in the geological candidate formations rock salt, clay stone and crystalline rock are being discussed. An open assessment of these concepts using numerical simulations requires physical models capturing the individual particularities of each rock type and associated geotechnical barrier concept to a comparable level of sophistication. In a joint work group of the Helmholtz Centre for Environmental Research (UFZ) and the German Federal Institute for Geosciences and Natural Resources (BGR), scientists of the UFZ are developing and implementing multiphysical process models while BGR scientists apply them to large scale analyses. The advances in simulation methods for waste repositories are incorporated into the open-source code OpenGeoSys. Here, recent application-driven progress in this context is highlighted. A robust implementation of visco-plasticity with temperature-dependent properties into a framework for the thermo-mechanical analysis of rock salt will be shown. The model enables the simulation of heat transport along with its consequences on the elastic response as well as on primary and secondary creep or the occurrence of dilatancy in the repository near field. Transverse isotropy, non-isothermal hydraulic processes and their coupling to mechanical stresses are taken into account for the analysis of repositories in clay stone. These processes are also considered in the near field analyses of engineered barrier systems, including the swelling/shrinkage of the bentonite material. The temperature-dependent saturation evolution around the heat-emitting waste container is described by different multiphase flow formulations. For all mentioned applications, we illustrate the workflow from model development and implementation, over verification and validation, to repository-scale application simulations using methods of high performance computing.

  3. Low-level Environmental Metals and Metalloids and Incident Pregnancy Loss

    PubMed Central

    Buck Louis, Germaine M.; Smarr, Melissa M.; Sundaram, Rajeshwari; Steuerwald, Amy J.; Sapra, Katherine J.; Lu, Zhaohui; Parsons, Patrick J.

    2017-01-01

    Environmental exposure to metals and metalloids is associated with pregnancy loss in some but not all studies. We assessed arsenic, cadmium, mercury, and lead concentrations in 501 couples upon trying for pregnancy and followed them throughout pregnancy to estimate the risk of incident pregnancy loss. Using Cox proportional hazard models, we estimated hazard ratios (HR) and 95% confidence intervals (CIs) for pregnancy loss after covariate adjustment for each partner modeled individually then we jointly modeled both partners’ concentrations. Incidence of pregnancy loss was 28%. In individual partner models, the highest adjusted HRs were observed for female and male blood cadmium (HR=1.08; CI 0.81, 1.44; HR=1.09; 95% CI 0.84, 1.41, respectively). In couple based models, neither partner’s blood cadmium concentrations were associated with loss (HR=1.01; 95% CI 0.75, 1.37; HR=0.92; CI 0.68, 1.25, respectively). We observed no evidence of a significant relation between metal(loids) at environmentally relevant concentrations and pregnancy loss. PMID:28163209

  4. Low-level environmental metals and metalloids and incident pregnancy loss.

    PubMed

    Buck Louis, Germaine M; Smarr, Melissa M; Sundaram, Rajeshwari; Steuerwald, Amy J; Sapra, Katherine J; Lu, Zhaohui; Parsons, Patrick J

    2017-04-01

    Environmental exposure to metals and metalloids is associated with pregnancy loss in some but not all studies. We assessed arsenic, cadmium, mercury, and lead concentrations in 501 couples upon trying for pregnancy and followed them throughout pregnancy to estimate the risk of incident pregnancy loss. Using Cox proportional hazard models, we estimated hazard ratios (HR) and 95% confidence intervals (CIs) for pregnancy loss after covariate adjustment for each partner modeled individually then we jointly modeled both partners' concentrations. Incidence of pregnancy loss was 28%. In individual partner models, the highest adjusted HRs were observed for female and male blood cadmium (HR=1.08; CI 0.81, 1.44; HR=1.09; 95% CI 0.84, 1.41, respectively). In couple based models, neither partner's blood cadmium concentrations were associated with loss (HR=1.01; 95% CI 0.75, 1.37; HR=0.92; CI 0.68, 1.25, respectively). We observed no evidence of a significant relation between metal(loids) at these environmentally relevant concentrations and pregnancy loss. Published by Elsevier Inc.

  5. A Household Is Not a Person: Consistency of Pro-Environmental Behavior in Adult Couples and the Accuracy of Proxy-Reports

    PubMed Central

    Seebauer, Sebastian; Fleiß, Jürgen; Schweighart, Markus

    2016-01-01

    Studies on environmental behavior commonly assume single respondents to represent their entire household or employ proxy-reporting, where participants answer for other household members. It is contested whether these practices yield valid results. Therefore, we interviewed 84 couples, wherein both household members provided self- and proxy-reports for their partner. For use of electrical household appliances, consumption of hot water, space heating, everyday mobility, and environmental values, many variables fail to achieve criteria for validity. Consistency (agreement between self-reports of household members) is higher if behaviors are undertaken jointly or negotiated between partners. Accuracy (agreement of proxy-reports with corresponding self-reports) is higher for routine behaviors and for behaviors easily observable by the partner. Overall, indices perform better than items on single behaviors. We caution against employing individual responses in place of the entire household. Interventions for energy conservation should approach the specific person undertaking the target behavior. PMID:28670000

  6. Coupling Front-End Separations, Ion Mobility Spectrometry, and Mass Spectrometry For Enhanced Multidimensional Biological and Environmental Analyses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zheng, Xueyun; Wojcik, Roza; Zhang, Xing

    Ion mobility spectrometry (IMS) is a widely used analytical technique for rapid molecular separations in the gas phase. IMS alone is useful, but its coupling with mass spectrometry (MS) and front-end separations has been extremely beneficial for increasing measurement sensitivity, peak capacity of complex mixtures, and the scope of molecular information in biological and environmental sample analyses. Multiple studies in disease screening and environmental evaluations have even shown these IMS-based multidimensional separations extract information not possible with each technique individually. This review highlights 3-dimensional separations using IMS-MS in conjunction with a range of front-end techniques, such as gas chromatography (GC),more » supercritical fluid chromatography (SFC), liquid chromatography (LC), solid phase extractions (SPE), capillary electrophoresis (CE), field asymmetric ion mobility spectrometry (FAIMS), and microfluidic devices. The origination, current state, various applications, and future capabilities for these multidimensional approaches are described to provide insight into the utility and potential of each technique.« less

  7. Coupling Front-End Separations, Ion Mobility Spectrometry, and Mass Spectrometry For Enhanced Multidimensional Biological and Environmental Analyses

    PubMed Central

    Zheng, Xueyun; Wojcik, Roza; Zhang, Xing; Ibrahim, Yehia M.; Burnum-Johnson, Kristin E.; Orton, Daniel J.; Monroe, Matthew E.; Moore, Ronald J.; Smith, Richard D.; Baker, Erin S.

    2017-01-01

    Ion mobility spectrometry (IMS) is a widely used analytical technique for rapid molecular separations in the gas phase. Though IMS alone is useful, its coupling with mass spectrometry (MS) and front-end separations is extremely beneficial for increasing measurement sensitivity, peak capacity of complex mixtures, and the scope of molecular information available from biological and environmental sample analyses. In fact, multiple disease screening and environmental evaluations have illustrated that the IMS-based multidimensional separations extract information that cannot be acquired with each technique individually. This review highlights three-dimensional separations using IMS-MS in conjunction with a range of front-end techniques, such as gas chromatography, supercritical fluid chromatography, liquid chromatography, solid-phase extractions, capillary electrophoresis, field asymmetric ion mobility spectrometry, and microfluidic devices. The origination, current state, various applications, and future capabilities of these multidimensional approaches are described in detail to provide insight into their uses and benefits. PMID:28301728

  8. Estimating the potential of energy saving and carbon emission mitigation of cassava-based fuel ethanol using life cycle assessment coupled with a biogeochemical process model.

    PubMed

    Jiang, Dong; Hao, Mengmeng; Fu, Jingying; Tian, Guangjin; Ding, Fangyu

    2017-09-14

    Global warming and increasing concentration of atmospheric greenhouse gas (GHG) have prompted considerable interest in the potential role of energy plant biomass. Cassava-based fuel ethanol is one of the most important bioenergy and has attracted much attention in both developed and developing countries. However, the development of cassava-based fuel ethanol is still faced with many uncertainties, including raw material supply, net energy potential, and carbon emission mitigation potential. Thus, an accurate estimation of these issues is urgently needed. This study provides an approach to estimate energy saving and carbon emission mitigation potentials of cassava-based fuel ethanol through LCA (life cycle assessment) coupled with a biogeochemical process model-GEPIC (GIS-based environmental policy integrated climate) model. The results indicate that the total potential of cassava yield on marginal land in China is 52.51 million t; the energy ratio value varies from 0.07 to 1.44, and the net energy surplus of cassava-based fuel ethanol in China is 92,920.58 million MJ. The total carbon emission mitigation from cassava-based fuel ethanol in China is 4593.89 million kgC. Guangxi, Guangdong, and Fujian are identified as target regions for large-scale development of cassava-based fuel ethanol industry. These results can provide an operational approach and fundamental data for scientific research and energy planning.

  9. A Physically Based Coupled Chemical and Physical Weathering Model for Simulating Soilscape Evolution

    NASA Astrophysics Data System (ADS)

    Willgoose, G. R.; Welivitiya, D.; Hancock, G. R.

    2015-12-01

    A critical missing link in existing landscape evolution models is a dynamic soil evolution models where soils co-evolve with the landform. Work by the authors over the last decade has demonstrated a computationally manageable model for soil profile evolution (soilscape evolution) based on physical weathering. For chemical weathering it is clear that full geochemistry models such as CrunchFlow and PHREEQC are too computationally intensive to be couplable to existing soilscape and landscape evolution models. This paper presents a simplification of CrunchFlow chemistry and physics that makes the task feasible, and generalises it for hillslope geomorphology applications. Results from this simplified model will be compared with field data for soil pedogenesis. Other researchers have previously proposed a number of very simple weathering functions (e.g. exponential, humped, reverse exponential) as conceptual models of the in-profile weathering process. The paper will show that all of these functions are possible for specific combinations of in-soil environmental, geochemical and geologic conditions, and the presentation will outline the key variables controlling which of these conceptual models can be realistic models of in-profile processes and under what conditions. The presentation will finish by discussing the coupling of this model with a physical weathering model, and will show sample results from our SSSPAM soilscape evolution model to illustrate the implications of including chemical weathering in the soilscape evolution model.

  10. Spectrally And Temporally Resolved Low-Light Level Video Microscopy

    NASA Astrophysics Data System (ADS)

    Wampler, John E.; Furukawa, Ruth; Fechheimer, Marcus

    1989-12-01

    The IDG law-light video microscope system was designed to aid studies of localization of subcellular luminescence sources and stimulus/response coupling in single living cells using luminescent probes. Much of the motivation for design of this instrument system came from the pioneering efforts of Dr. Reynolds (Reynolds, Q. Rev. Biophys. 5, 295-347; Reynolds and Taylor, Bioscience 30, 586-592) who showed the value of intensified video camera systems for detection and localizion of fluorescence and bioluminescence signals from biological tissues. Our instrument system has essentially two roles, 1) localization and quantitation of very weak bioluminescence signals and 2) quantitation of intracellular environmental characteristics such as pH and calcium ion concentrations using fluorescent and bioluminescent probes. The instrument system exhibits over one million fold operating range allowing visualization and enhancement of quantum limited images with quantum limited response, spectral analysis of fluorescence signals, and transmitted light imaging. The computer control of the system implements rapid switching between light regimes, spatially resolved spectral scanning, and digital data processing for spectral shape analysis and for detailed analysis of the statistical distribution of single cell measurements. The system design and software algorithms used by the system are summarized. These design criteria are illustrated with examples taken from studies of bioluminescence, applications of bioluminescence to study developmental processes and gene expression in single living cells, and applications of fluorescent probes to study stimulus/response coupling in living cells.

  11. Estimating the potential of energy saving and carbon emission mitigation of cassava-based fuel ethanol using life cycle assessment coupled with a biogeochemical process model

    NASA Astrophysics Data System (ADS)

    Jiang, Dong; Hao, Mengmeng; Fu, Jingying; Tian, Guangjin; Ding, Fangyu

    2017-09-01

    Global warming and increasing concentration of atmospheric greenhouse gas (GHG) have prompted considerable interest in the potential role of energy plant biomass. Cassava-based fuel ethanol is one of the most important bioenergy and has attracted much attention in both developed and developing countries. However, the development of cassava-based fuel ethanol is still faced with many uncertainties, including raw material supply, net energy potential, and carbon emission mitigation potential. Thus, an accurate estimation of these issues is urgently needed. This study provides an approach to estimate energy saving and carbon emission mitigation potentials of cassava-based fuel ethanol through LCA (life cycle assessment) coupled with a biogeochemical process model—GEPIC (GIS-based environmental policy integrated climate) model. The results indicate that the total potential of cassava yield on marginal land in China is 52.51 million t; the energy ratio value varies from 0.07 to 1.44, and the net energy surplus of cassava-based fuel ethanol in China is 92,920.58 million MJ. The total carbon emission mitigation from cassava-based fuel ethanol in China is 4593.89 million kgC. Guangxi, Guangdong, and Fujian are identified as target regions for large-scale development of cassava-based fuel ethanol industry. These results can provide an operational approach and fundamental data for scientific research and energy planning.

  12. Environmental Effects on Mesozooplankton Size Structure and Export Flux at Station ALOHA, North Pacific Subtropical Gyre

    NASA Astrophysics Data System (ADS)

    Valencia, Bellineth; Décima, Moira; Landry, Michael R.

    2018-02-01

    Using size-fractionated mesozooplankton biomass data collected over 23 years (1994-2016) of increasing primary production (PP) at station ALOHA (A Long-Term Oligotrophic Habitat Assessment), we evaluate how changing environmental conditions affect mesozooplankton size structure, trophic cycling, and export fluxes in the subtropical North Pacific. From generalized additive model analysis, size structure is significantly influenced by a nonlinear relationship with sea surface temperature that is mainly driven by the strong 1997-1998 El Niño and a positive and linear relationship with PP. Increasing PP has more strongly enhanced the biomass of smaller (0.2-0.5 mm) and larger (>5 mm) mesozooplankton, increasing evenness of the biomass spectra, while animals of 2-5 mm, the major size class for vertically migrating mesozooplankton, show no long-term trend. Measured PP is sufficient to meet feeding requirements that satisfy mesozooplankton respiration and growth rates, as determined by commonly used empirical relationships based on animal size and temperature, consistent with a tightly coupled food web with one intermediate level for protistan consumers. Estimated fecal pellet production suggests an enhanced contribution of mesozooplankton to passive particle export relative to the material collected in 150 m sediment traps. In contrast, the biomass of vertically migrants does not vary systematically with PP due to the varying responses of the different size classes. These results illustrate some complexities in understanding how varying environmental conditions can affect carbon cycling and export processes at the community level in open-ocean oligotrophic systems, which need to be confirmed and better understood by process-oriented mechanistic study.

  13. Increasing the production efficiency and reducing the environmental impacts of hydraulic fracturing

    NASA Astrophysics Data System (ADS)

    Viswanathan, H. S.

    2016-12-01

    Shale gas is an unconventional fossil energy resource profoundly impacting US energy independence and is projected to last for at least 100 years. Production of methane and other hydrocarbons from low permeability shale involves hydraulic fracturing of rock, establishing fracture connectivity, and multiphase fluid-flow and reaction processes all of which are poorly understood. The result is inefficient extraction with many environmental concerns. A science-based capability is required to quantify the governing mesoscale fluid-solid interactions, including microstructural control of fracture patterns and the interaction of engineered fluids with hydrocarbon flow. These interactions depend on coupled thermo-hydro-mechanical-chemical (THMC) processes over scales from microns to tens of meters. Determining the key mechanisms in subsurface THMC systems has been impeded due to the lack of sophisticated experimental methods to measure fracture aperture and connectivity, multiphase permeability, and chemical exchange capacities at the high temperature, pressure, and stresses present in the subsurface. In this study, we developed and prototyped the microfluidic and triaxial core flood experiments required to reveal the fundamental dynamics of fracture-fluid interactions. The goal is transformation of hydraulic fracturing from present ad hoc approaches to science-based strategies while safely enhancing production. Specifically, we have demonstrated an integrated experimental/modeling approach that allows for a comprehensive characterization of fluid-solid interactions and develop models that can be used to determine the reservoir operating conditions necessary to gain a degree of control over fracture generation, fluid flow, and interfacial processes over a range of subsurface conditions.

  14. Research infrastructure support to address ecosystem dynamics

    NASA Astrophysics Data System (ADS)

    Los, Wouter

    2014-05-01

    Predicting the evolution of ecosystems to climate change or human pressures is a challenge. Even understanding past or current processes is complicated as a result of the many interactions and feedbacks that occur within and between components of the system. This talk will present an example of current research on changes in landscape evolution, hydrology, soil biogeochemical processes, zoological food webs, and plant community succession, and how these affect feedbacks to components of the systems, including the climate system. Multiple observations, experiments, and simulations provide a wealth of data, but not necessarily understanding. Model development on the coupled processes on different spatial and temporal scales is sensitive for variations in data and of parameter change. Fast high performance computing may help to visualize the effect of these changes and the potential stability (and reliability) of the models. This may than allow for iteration between data production and models towards stable models reducing uncertainty and improving the prediction of change. The role of research infrastructures becomes crucial is overcoming barriers for such research. Environmental infrastructures are covering physical site facilities, dedicated instrumentation and e-infrastructure. The LifeWatch infrastructure for biodiversity and ecosystem research will provide services for data integration, analysis and modeling. But it has to cooperate intensively with the other kinds of infrastructures in order to support the iteration between data production and model computation. The cooperation in the ENVRI project (Common operations of environmental research infrastructures) is one of the initiatives to foster such multidisciplinary research.

  15. An Integrated Modeling Approach for Describing Fate and Transport of Perfluorinated Compounds (PFCs) in Estuarine Reservoir

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Nguyen Viet, T.; Wang, X.; Chen, H.; Gin, K. Y. H.

    2014-12-01

    The fate and transport processes of emerging contaminants in aquatic ecosystems are complex, which are not only determined by their own properties but also influenced by the environmental setting, physical, chemical and biological processes. A 3D-emerging contaminant model has been developed based on Delft3D water quality model and coupled with a hydrodynamic model and a catchment-scale 1D- hydrological and hydraulic model to study the possible fate and transport mechanisms of perfluorinated compounds (PFCs) in Marina Reservoir in Singapore. The main processes in the contaminant model include partitioning (among detritus, dissolved organic matter and phytoplankton), settling, resuspension and degradation. We used the integrated model to quantify the distribution of the total PFCs and two major components, namely perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in the water, sediments and organisms in the reservoir. The model yielded good agreement with the field measurements when evaluated based on the datasets in 2009 and 2010 as well as recent observations in 2013 and 2014. Our results elucidate that the model can be a useful tool to characterize the occurrence, sources, sinks and trends of PFCs both in the water column and in the sediments in the reservoir. Thisapproach provides a better understanding of mechanisms that influence the fate and transport of emerging contaminants and lays down a framework for future experiments to further explore how the dominant environmental factors change towards mitigation of emerging contaminants in the reservoirs.

  16. Cryptic diversity in a fig wasp community-morphologically differentiated species are sympatric but cryptic species are parapatric.

    PubMed

    Darwell, C T; Cook, J M

    2017-02-01

    A key debate in ecology centres on the relative importance of niche and neutral processes in determining patterns of community assembly with particular focus on whether ecologically similar species with similar functional traits are able to coexist. Meanwhile, molecular studies are increasingly revealing morphologically indistinguishable cryptic species with presumably similar ecological roles. Determining the geographic distribution of such cryptic species provides opportunities to contrast predictions of niche vs. neutral models. Discovery of sympatric cryptic species increases alpha diversity and supports neutral models, while documentation of allopatric/parapatric cryptic species increases beta diversity and supports niche models. We tested these predictions using morphological and molecular data, coupled with environmental niche modelling analyses, of a fig wasp community along its 2700-km latitudinal range. Molecular methods increased previous species diversity estimates from eight to eleven species, revealing morphologically cryptic species in each of the four wasp genera studied. Congeneric species pairs that were differentiated by a key morphological functional trait (ovipositor length) coexisted sympatrically over large areas. In contrast, morphologically similar species, with similar ovipositor lengths, typically showed parapatric ranges with very little overlap. Despite parapatric ranges, environmental niche models of cryptic congeneric pairs indicate large regions of potential sympatry, suggesting that competitive processes are important in determining the distributions of ecologically similar species. Niche processes appear to structure this insect community, and cryptic diversity may typically contribute mostly to beta rather than alpha diversity. © 2016 John Wiley & Sons Ltd.

  17. The Experience of Chinese Couples Undergoing In Vitro Fertilization Treatment: Perception of the Treatment Process and Partner Support.

    PubMed

    Ying, Li-Ying; Wu, Lai Har; Loke, Alice Yuen

    2015-01-01

    Couples undergoing In Vitro Fertilization (IVF) Treatment suffer as dyads from the stressful experience of the painful treatment and the fear that the IVF cycle will fail. They are likely to report that their marital relationship has become unstable due to the prolonged period of treatment. This is a qualitative study that was conducted to explore the experiences that Chinese couples have had with IVF treatment, especially their perceptions of the process and the support between couples. The interviews revealed that couples suffered from the process, experiencing physical and emotional pain, struggling with the urgency and inflexibility of bearing a child, and experiencing disturbances in their daily routines and work. The participants described how they endured the hardships as a couple and how it affected their relationship. The couples felt that sharing feelings and supporting each other contribute to psychological well-being and improves the marital relationship. They also identified some unfavorable aspects in their partner relationship. They were ambivalent about receiving social support from friends and family members. With the couples indicating that the support that they received from each other affected their experience during the treatment process, it is suggested that a supportive intervention that focuses on enhancing the partnership of the couples and dealing with their inflexibility on the issue of bearing a child might result in improvements in the psychological status and marital relationship of infertile couples undergoing IVF treatment.

  18. The Experience of Chinese Couples Undergoing In Vitro Fertilization Treatment: Perception of the Treatment Process and Partner Support

    PubMed Central

    Ying, Li-Ying; Wu, Lai Har; Loke, Alice Yuen

    2015-01-01

    Background Couples undergoing In Vitro Fertilization (IVF) Treatment suffer as dyads from the stressful experience of the painful treatment and the fear that the IVF cycle will fail. They are likely to report that their marital relationship has become unstable due to the prolonged period of treatment. Methods This is a qualitative study that was conducted to explore the experiences that Chinese couples have had with IVF treatment, especially their perceptions of the process and the support between couples. Results The interviews revealed that couples suffered from the process, experiencing physical and emotional pain, struggling with the urgency and inflexibility of bearing a child, and experiencing disturbances in their daily routines and work. The participants described how they endured the hardships as a couple and how it affected their relationship. The couples felt that sharing feelings and supporting each other contribute to psychological well-being and improves the marital relationship. They also identified some unfavorable aspects in their partner relationship. They were ambivalent about receiving social support from friends and family members. Conclusions With the couples indicating that the support that they received from each other affected their experience during the treatment process, it is suggested that a supportive intervention that focuses on enhancing the partnership of the couples and dealing with their inflexibility on the issue of bearing a child might result in improvements in the psychological status and marital relationship of infertile couples undergoing IVF treatment. PMID:26431545

  19. Coupled atmosphere-biophysics-hydrology models for environmental modeling

    USGS Publications Warehouse

    Walko, R.L.; Band, L.E.; Baron, Jill S.; Kittel, T.G.F.; Lammers, R.; Lee, T.J.; Ojima, D.; Pielke, R.A.; Taylor, C.; Tague, C.; Tremback, C.J.; Vidale, P.L.

    2000-01-01

    The formulation and implementation of LEAF-2, the Land Ecosystem–Atmosphere Feedback model, which comprises the representation of land–surface processes in the Regional Atmospheric Modeling System (RAMS), is described. LEAF-2 is a prognostic model for the temperature and water content of soil, snow cover, vegetation, and canopy air, and includes turbulent and radiative exchanges between these components and with the atmosphere. Subdivision of a RAMS surface grid cell into multiple areas of distinct land-use types is allowed, with each subgrid area, or patch, containing its own LEAF-2 model, and each patch interacts with the overlying atmospheric column with a weight proportional to its fractional area in the grid cell. A description is also given of TOPMODEL, a land hydrology model that represents surface and subsurface downslope lateral transport of groundwater. Details of the incorporation of a modified form of TOPMODEL into LEAF-2 are presented. Sensitivity tests of the coupled system are presented that demonstrate the potential importance of the patch representation and of lateral water transport in idealized model simulations. Independent studies that have applied LEAF-2 and verified its performance against observational data are cited. Linkage of RAMS and TOPMODEL through LEAF-2 creates a modeling system that can be used to explore the coupled atmosphere–biophysical–hydrologic response to altered climate forcing at local watershed and regional basin scales.

  20. Improving Subtropical Boundary Layer Cloudiness in the 2011 NCEP GFS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fletcher, J. K.; Bretherton, Christopher S.; Xiao, Heng

    2014-09-23

    The current operational version of National Centers for Environmental Prediction (NCEP) Global Forecasting System (GFS) shows significant low cloud bias. These biases also appear in the Coupled Forecast System (CFS), which is developed from the GFS. These low cloud biases degrade seasonal and longer climate forecasts, particularly of short-wave cloud radiative forcing, and affect predicted sea surface temperature. Reducing this bias in the GFS will aid the development of future CFS versions and contributes to NCEP's goal of unified weather and climate modelling. Changes are made to the shallow convection and planetary boundary layer parameterisations to make them more consistentmore » with current knowledge of these processes and to reduce the low cloud bias. These changes are tested in a single-column version of GFS and in global simulations with GFS coupled to a dynamical ocean model. In the single-column model, we focus on changing parameters that set the following: the strength of shallow cumulus lateral entrainment, the conversion of updraught liquid water to precipitation and grid-scale condensate, shallow cumulus cloud top, and the effect of shallow convection in stratocumulus environments. Results show that these changes improve the single-column simulations when compared to large eddy simulations, in particular through decreasing the precipitation efficiency of boundary layer clouds. These changes, combined with a few other model improvements, also reduce boundary layer cloud and albedo biases in global coupled simulations.« less

Top