WorldWideScience

Sample records for coupling state-of-the-science subsurface

  1. COUPLING STATE-OF-THE-SCIENCE SUBSURFACE SIMULATION WITH ADVANCED USER INTERFACE AND PARALLEL VISUALIZATION: SBIR Phase I Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Hardeman, B.; Swenson, D.; Finsterle, S.; Zhou, Q.

    2008-04-30

    This is a Phase I report on a project to significantly enhance existing subsurface simulation software using leadership-class computing resources, allowing researchers to solve problems with greater speed and accuracy. Subsurface computer simulation is used for monitoring the behavior of contaminants around nuclear waste disposal and storage areas, groundwater flow, environmental remediation, carbon sequestration, methane hydrate production, and geothermal energy reservoir analysis. The Phase I project was a collaborative effort between Thunderhead Engineering (project lead and developers of a commercial pre- and post-processor for the TOUGH2 simulator) and Lawrence Berkeley National Laboratory (developers of the TOUGH2 simulator for subsurface flow). The Phase I project successfully identified the technical approaches to be implemented in Phase II.

  2. Photochemical oxidants: state of the science.

    Science.gov (United States)

    Kley, D; Kleinmann, M; Sanderman, H; Krupa, S

    1999-01-01

    Atmospheric photochemical processes resulting in the production of tropospheric ozone (O(3)) and other oxidants are described. The spatial and temporal variabilities in the occurrence of surface level oxidants and their relationships to air pollution meteorology are discussed. Models of photooxidant formation are reviewed in the context of control strategies and comparisons are provided of the air concentrations of O(3) at select geographic locations around the world. This overall oxidant (O(3)) climatology is coupled to human health and ecological effects. The discussion of the effects includes both acute and chronic responses, mechanisms of action, human epidemiological and plant population studies and briefly, efforts to establish cause-effect relationships through numerical modeling. A short synopsis is provided of the interactive effects of O(3) with other abiotic and biotic factors. The overall emphasis of the paper is on identifying the current uncertainties and gaps in our understanding of the state of the science and some suggestions as to how they may be addressed.

  3. Aviation Noise Impacts: State of the Science

    Directory of Open Access Journals (Sweden)

    Mathias Basner

    2017-01-01

    Full Text Available Noise is defined as “unwanted sound.” Aircraft noise is one, if not the most detrimental environmental effect of aviation. It can cause community annoyance, disrupt sleep, adversely affect academic performance of children, and could increase the risk for cardiovascular disease of people living in the vicinity of airports. In some airports, noise constrains air traffic growth. This consensus paper was prepared by the Impacts of Science Group of the Committee for Aviation Environmental Protection of the International Civil Aviation Organization and summarizes the state of the science of noise effects research in the areas of noise measurement and prediction, community annoyance, children’s learning, sleep disturbance, and health. It also briefly discusses civilian supersonic aircraft as a future source of aviation noise.

  4. Aviation Noise Impacts: State of the Science

    Science.gov (United States)

    Basner, Mathias; Clark, Charlotte; Hansell, Anna; Hileman, James I.; Janssen, Sabine; Shepherd, Kevin; Sparrow, Victor

    2017-01-01

    Noise is defined as “unwanted sound.” Aircraft noise is one, if not the most detrimental environmental effect of aviation. It can cause community annoyance, disrupt sleep, adversely affect academic performance of children, and could increase the risk for cardiovascular disease of people living in the vicinity of airports. In some airports, noise constrains air traffic growth. This consensus paper was prepared by the Impacts of Science Group of the Committee for Aviation Environmental Protection of the International Civil Aviation Organization and summarizes the state of the science of noise effects research in the areas of noise measurement and prediction, community annoyance, children’s learning, sleep disturbance, and health. It also briefly discusses civilian supersonic aircraft as a future source of aviation noise. PMID:29192612

  5. Examination of the seepage face boundary condition in subsurface and coupled surface/subsurface hydrological models

    Science.gov (United States)

    Scudeler, C.; Paniconi, C.; Pasetto, D.; Putti, M.

    2017-03-01

    A seepage face is a nonlinear dynamic boundary that strongly affects pressure head distributions, water table fluctuations, and flow patterns. Its handling in hydrological models, especially under complex conditions such as heterogeneity and coupled surface/subsurface flow, has not been extensively studied. In this paper, we compare the treatment of the seepage face as a static (Dirichlet) versus dynamic boundary condition, we assess its resolution under conditions of layered heterogeneity, we examine its interaction with a catchment outlet boundary, and we investigate the effects of surface/subsurface exchanges on seepage faces forming at the land surface. The analyses are carried out with an integrated catchment hydrological model. Numerical simulations are performed for a synthetic rectangular sloping aquifer and for an experimental hillslope from the Landscape Evolution Observatory. The results show that the static boundary condition is not always an adequate stand-in for a dynamic seepage face boundary condition, especially under conditions of high rainfall, steep slope, or heterogeneity; that hillslopes with layered heterogeneity give rise to multiple seepage faces that can be highly dynamic; that seepage face and outlet boundaries can coexist in an integrated hydrological model and both play an important role; and that seepage faces at the land surface are not always controlled by subsurface flow. The paper also presents a generalized algorithm for resolving seepage face outflow that handles heterogeneity in a simple way, is applicable to unstructured grids, and is shown experimentally to be equivalent to the treatment of atmospheric boundary conditions in subsurface flow models.

  6. Developmental Programming: State-of-the-Science and Future Directions

    Science.gov (United States)

    Sutton, Elizabeth F.; Gilmore, L. Anne; Dunger, David B.; Heijmans, Bas T.; Hivert, Marie-France; Ling, Charlotte; Martinez, J. Alfredo; Ozanne, Susan E.; Simmons, Rebecca A.; Szyf, Moshe; Waterland, Robert A.; Redman, Leanne M.; Ravussin, Eric

    2016-01-01

    Objective On December 8–9, 2014, the Pennington Biomedical Research Center convened a scientific symposium to review the state-of-the-science and future directions for the study of developmental programming of obesity and chronic disease. The objectives of the symposium were to discuss: (i) past and current scientific advances in animal models, population-based cohort studies and human clinical trials, (ii) the state-of-the-science of epigenetic-based research, and (iii) considerations for future studies. Results The overarching goal was to provide a comprehensive assessment of the state of the scientific field, to identify research gaps and opportunities for future research in order to identify and understand the mechanisms contributing to the developmental programming of health and disease. Conclusions Identifying the mechanisms which cause or contribute to developmental programming of future generations will be invaluable to the scientific and medical community. The ability to intervene during critical periods of prenatal and early postnatal life to promote lifelong health is the ultimate goal. Considerations for future research including the use of animal models, the study design in human cohorts with considerations about the timing of the intrauterine exposure and the resulting tissue specific epigenetic signature were extensively discussed and are presented in this meeting summary. PMID:27037645

  7. Simulation in healthcare and nursing: state of the science.

    Science.gov (United States)

    Cannon-Diehl, Margaret Roseann

    2009-01-01

    The face of nursing education and continuing education as we currently know it is changing at a phenomenal pace. The state of the science of simulation in nursing and healthcare exist on a continuum of various types of simulation. Several driving forces have influenced the development and diffusion of the science of simulation. Today's consumers of education have higher expectations for curricula. Healthcare is evolving with fewer resources and more complex roles. Advancing technology is creating a dependence on simulation as a teaching and learning strategy. Society in general, in the form of both public and professional organizations, supports simulation as a viable teaching and learning strategy. Current use and future research will decide the fate of simulation and if it will become embedded in nursing and healthcare education.

  8. Uncertainty during breast diagnostic evaluation: state of the science.

    Science.gov (United States)

    Montgomery, Mariann

    2010-01-01

    To present the state of the science on uncertainty in relationship to the experiences of women undergoing diagnostic evaluation for suspected breast cancer. Published articles from Medline, CINAHL, PubMED, and PsycINFO from 1983-2008 using the following key words: breast biopsy, mammography, uncertainty, reframing, inner strength, and disruption. Fifty research studies were examined with all reporting the presence of anxiety persisting throughout the diagnostic evaluation until certitude is achieved through the establishment of a definitive diagnosis. Indirect determinants of uncertainty for women undergoing breast diagnostic evaluation include measures of anxiety, depression, social support, emotional responses, defense mechanisms, and the psychological impact of events. Understanding and influencing the uncertainty experience have been suggested to be key in relieving psychosocial distress and positively influencing future screening behaviors. Several studies examine correlational relationships among anxiety, selection of coping methods, and demographic factors that influence uncertainty. A gap exists in the literature with regard to the relationship of inner strength and uncertainty. Nurses can be invaluable in assisting women in coping with the uncertainty experience by providing positive communication and support. Nursing interventions should be designed and tested for their effects on uncertainty experienced by women undergoing a breast diagnostic evaluation.

  9. Coupled modelling of subsurface water flux for an integrated flood risk management

    Directory of Open Access Journals (Sweden)

    T. Sommer

    2009-07-01

    Full Text Available Flood events cause significant damage not only on the surface but also underground. Infiltration of surface water into soil, flooding through the urban sewer system and, in consequence, rising groundwater are the main causes of subsurface damage. The modelling of flooding events is an important part of flood risk assessment. The processes of subsurface discharge of infiltrated water necessitate coupled modelling tools of both, surface and subsurface water fluxes. Therefore, codes for surface flooding, for discharge in the sewerage system and for groundwater flow were coupled with each other. A coupling software was used to amalgamate the individual programs in terms of mapping between the different model geometries, time synchronization and data exchange. The coupling of the models was realized on two scales in the Saxon capital of Dresden (Germany. As a result of the coupled modelling it could be shown that surface flooding dominates processes of any flood event. Compared to flood simulations without coupled modelling no substantial changes of the surface inundation area could be determined. Regarding sewerage, the comparison between the influx of groundwater into sewerage and the loading due to infiltration by flood water showed infiltration of surface flood water to be the main reason for sewerage overloading. Concurrent rainfalls can intensify the problem. The infiltration of the sewerage system by rising groundwater contributes only marginally to the loading of the sewerage and the distribution of water by sewerage has only local impacts on groundwater rise. However, the localization of risk areas due to rising groundwater requires the consideration of all components of the subsurface water fluxes. The coupled modelling has shown that high groundwater levels are the result of a multi-causal process that occurs before and during the flood event.

  10. State of the Science in Dried Blood Spots.

    Science.gov (United States)

    Freeman, Jeffrey D; Rosman, Lori M; Ratcliff, Jeremy D; Strickland, Paul T; Graham, David R; Silbergeld, Ellen K

    2017-11-29

    Advancements in the quality and availability of highly sensitive analytical instrumentation and methodologies have led to increased interest in the use of microsamples. Among microsamples, dried blood spots (DBS) are the most well-known. Although there have been a variety of review papers published on DBS, there has been no attempt at describing the full range of analytes measurable in DBS, or any systematic approach published for characterizing the strengths and weaknesses associated with adoption of DBS analyses. A scoping review of reviews methodology was used for characterizing the state of the science in DBS. We identified 2018 analytes measured in DBS and found every common analytic method applied to traditional liquid samples had been applied to DBS samples. Analytes covered a broad range of biomarkers that included genes, transcripts, proteins, and metabolites. Strengths of DBS enable its application in most clinical and laboratory settings, and the removal of phlebotomy and the need for refrigeration have expanded biosampling to hard-to-reach and vulnerable populations. Weaknesses may limit adoption in the near term because DBS is a nontraditional sample often requiring conversion of measurements to plasma or serum values. Opportunities presented by novel methodologies may obviate many of the current limitations, but threats around the ethical use of residual samples must be considered by potential adopters. DBS provide a wide range of potential applications that extend beyond the reach of traditional samples. Current limitations are serious but not intractable. Technological advancements will likely continue to minimize constraints around DBS adoption. © 2017 American Association for Clinical Chemistry.

  11. Workshop on Agricultural Air Quality: State of the science

    Science.gov (United States)

    Aneja, Viney P.; Blunden, Jessica; Roelle, Paul A.; Schlesinger, William H.; Knighton, Raymond; Niyogi, Dev; Gilliam, Wendell; Jennings, Greg; Duke, Clifford S.

    The first Workshop on Agricultural Air Quality: State of the Science was held at the Bolger Center in Potomac, Maryland from 4 to 8 June 2006. This international conference assembled approximately 350 people representing 25 nations from 5 continents, with disciplines ranging from atmospheric chemistry to soil science. The workshop was designed as an open forum in which participants could openly exchange the most current knowledge and learn about numerous international perspectives regarding agricultural air quality. Participants represented many stakeholder groups concerned with the growing need to assess agricultural impacts on the atmosphere and to develop beneficial policies to improve air quality. The workshop focused on identifying methods to improve emissions inventories and best management practices for agriculture. Workshop participants also made recommendations for technological and methodological improvements in current emissions measurement and modeling practices. The workshop commenced with a session on agricultural emissions and was followed by international perspectives from the United States, Europe, Australia, India, and South America. This paper summarizes the findings and issues of the workshop and articulates future research needs. These needs were identified in three general areas: (1) improvement of emissions measurement; (2) development of appropriate emission factors; and (3) implementation of best management practices (BMPs) to minimize negative environmental impacts. Improvements in the appropriate measurements will inform decisions regarding US farming practices. A need was demonstrated for a national/international network to monitor atmospheric emissions from agriculture and their subsequent depositions to surrounding areas. Information collected through such a program may be used to assess model performance and could be critical for evaluating any future regulatory policies or BMPs. The workshop concluded that efforts to maximize

  12. Insulated conductor temperature limited heater for subsurface heating coupled in a three-phase WYE configuration

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Sandberg, Chester Ledlie (Palo Alto, CA)

    2010-11-09

    A heating system for a subsurface formation is described. The heating system includes a first heater, a second heater, and a third heater placed in an opening in the subsurface formation. Each heater includes: an electrical conductor; an insulation layer at least partially surrounding the electrical conductor; and an electrically conductive sheath at least partially surrounding the insulation layer. The electrical conductor is electrically coupled to the sheath at a lower end portion of the heater. The lower end portion is the portion of the heater distal from a surface of the opening. The first heater, the second heater, and the third heater are electrically coupled at the lower end portions of the heaters. The first heater, the second heater, and the third heater are configured to be electrically coupled in a three-phase wye configuration.

  13. The State of the Science of Health Literacy Measurement.

    Science.gov (United States)

    Nguyen, Tam H; Paasche-Orlow, Michael K; McCormack, Lauren A

    2017-01-01

    Advancing health literacy (HL) research requires high-quality HL measures. This chapter provides an overview of the state of the science of HL measurement: where the field started, currently is, and should be going. It is divided into eight key sections looking at (1) the history of HL measurement, (2) the relationship between HL definitions and measurement, (3) the HL conceptual domains most and least frequently measured, (4) the methods used to validate HL measures, (5) the characteristics of the participants in the measurement validation studies, (6) the practical considerations related to administering HL measures, (7) the advantages and disadvantages of using objective versus subjective HL measures, and (8) future directions for HL measurement. Based on the material presented in this chapter, the following conclusions can be drawn. First, there is an enormous proliferation of HL measures and this growth presents both opportunities and challenges for the field. Second, to move the field forward, there is an urgent need to better align HL measurement with definitions of HL. Third, some HL domains, such as numeracy, are measured more often than others, such as speaking and listening. Consequently, it is important to think about novel mechanisms to measure HL domains that are rarely measured. Fourth, HL measures are most often developed, validated, and refined using classical measurement approaches. However, strong empirical and practical rationales suggest making an assertive shift toward using modern measurement approaches. Fifth, most HL measures are not well validated for use in minority populations; consequently, future validation studies should be mindful of validation samples. Sixth, HL measures can be administered using multiple modes, most frequently via paper-and-pencil surveys. Identifying which mode of administration is most suitable requires reflecting on the underlying measurement purpose and the characteristics of the participants being measured

  14. Modelling nitrogen removal in a coupled HRP and unplanted horizontal flow subsurface gravel bed constructed wetland

    Science.gov (United States)

    Mayo, A. W.; Mutamba, J.

    A coupled model was developed that incorporates all the major nitrogen transformation mechanisms influencing nitrogen removal in aquatic systems. The model simulates nitrogen transformation and removal processes in the high rate pond (HRP) and the subsurface constructed wetland unit (SSCW). The model considered organic nitrogen (ON), ammonia nitrogen (NH 3-N), and nitrate nitrogen ( NO3--N) as the major forms of nitrogen involved in the transformation chains. The influencing transformation mechanisms considered in the model include uptake of inorganic nitrogen by algae and bacteria, mineralization, sedimentation, volatilisation of ammonia and nitrification coupled with denitrification processes. The results showed that improved nitrogen removal occurred with increase in hydraulic time of the HRP unit. It was also revealed that the HRP can effectively be used to promote nitrification and subsurface flow gravel bed constructed wetland can be used as a denitrifying unit. The most efficient mechanisms were determined using a transformation model. The model indicated that nitrification and mineralization were dominant contributing 51.1% and 14.9%, respectively. Denitrification and mineralization were most significant in the SSCW accounting for 43.5% and 16.7%, respectively. Nitrification-denitrification route was observed to be the most significant mechanism for nitrogen removal in the coupled system with an overall contribution of 53%. The model predicted the overall nitrogen removal as 37% compared to 38.4% obtained from field measurements.

  15. State of the Science Meeting: Burn Care: Goals for Treatment and Research

    National Research Council Canada - National Science Library

    Palmieri, Tina L

    2006-01-01

    The Burn State of the Science Research Conference achieved its stated purpose: the identification and prioritization of burn research goals for the next decade and the delineation of the resources needed to achieve those goals...

  16. Quantifying the surface-subsurface biogeochemical coupling during the VERTIGO ALOHA and K2 studies

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, P.W.; Gall, M.P.; Silver, M.W.; Bishop, J.K.B.; Coale, Susan L.; Bidigare, Robert R.

    2008-02-25

    A central question addressed by the VERTIGO (VERtical Transport In the Global Ocean) study was 'What controls the efficiency of particle export between the surface and subsurface ocean'? Here, we present data from sites at ALOHA (N Central Pacific Gyre) and K2 (NW subarctic Pacific) on phytoplankton processes, and relate them via a simple planktonic foodweb model, to subsurface particle export (150-500 m). Three key factors enable quantification of the surface-subsurface coupling: a sampling design to overcome the temporal lag and spatial displacement between surface and subsurface processes; data on the size-partitioning of Net Primary Production (NPP) and subsequent transformations prior to export; estimates of the ratio of algal- to faecal-mediated vertical export flux. At ALOHA, phytoplankton were characterized by low stocks, NPP, F{sub v}/F{sub m} (N-limited), and were dominated by picoplankton. The HNLC waters at K2 were characterized by both two-fold changes in NPP and floristic shifts (high to low proportion of diatoms) between deployment 1 and 2. Prediction of export exiting the euphotic zone was based on size-partitioning of NPP, a copepod-dominated foodweb and a ratio of 0.2 (ALOHA) and 0.1 (K2) for algal:faecal particle flux. Predicted export was 20-22 mg POC m{sup -2} d{sup -1} at ALOHA (i.e. 10-11% NPP (0-125 m); 1.1-1.2 x export flux at 150 m (E{sub 150}). At K2, export was 111 mg C m{sup -2} d{sup -1} (21% NPP (0-50 m); 1.8 x E{sub 150}) and 33 mg POC m{sup -2} d{sup -1} (11% NPP, 0-55 m); 1.4 x E{sub 150}) for deployments 1 and 2, respectively. This decrease in predicted export at K2 matches the observed trend for E{sub 150}. Also, the low attenuation of export flux from 60 to 150 m is consistent with that between 150 to 500 m. This strong surface-subsurface coupling suggests that phytoplankton productivity and floristics play a key role at K2 in setting export flux, and moreover that pelagic particle transformations by grazers strongly

  17. A coupled surface/subsurface flow model accounting for air entrapment and air pressure counterflow

    DEFF Research Database (Denmark)

    Delfs, Jens Olaf; Wang, Wenqing; Kalbacher, Thomas

    2013-01-01

    the mass exchange between compartments. A benchmark test, which is based on a classic experimental data set on infiltration excess (Horton) overland flow, identified a feedback mechanism between surface runoff and soil air pressures. Our study suggests that air compression in soils amplifies surface runoff......This work introduces the soil air system into integrated hydrology by simulating the flow processes and interactions of surface runoff, soil moisture and air in the shallow subsurface. The numerical model is formulated as a coupled system of partial differential equations for hydrostatic (diffusive...... wave) shallow flow and two-phase flow in a porous medium. The simultaneous mass transfer between the soil, overland, and atmosphere compartments is achieved by upgrading a fully established leakance concept for overland-soil liquid exchange to an air exchange flux between soil and atmosphere. In a new...

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

    Science.gov (United States)

    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.

  19. Dual states estimation of a subsurface flow-transport coupled model using ensemble Kalman filtering

    KAUST Repository

    El Gharamti, Mohamad

    2013-10-01

    Modeling the spread of subsurface contaminants requires coupling a groundwater flow model with a contaminant transport model. Such coupling may provide accurate estimates of future subsurface hydrologic states if essential flow and contaminant data are assimilated in the model. Assuming perfect flow, an ensemble Kalman filter (EnKF) can be used for direct data assimilation into the transport model. This is, however, a crude assumption as flow models can be subject to many sources of uncertainty. If the flow is not accurately simulated, contaminant predictions will likely be inaccurate even after successive Kalman updates of the contaminant model with the data. The problem is better handled when both flow and contaminant states are concurrently estimated using the traditional joint state augmentation approach. In this paper, we introduce a dual estimation strategy for data assimilation into a one-way coupled system by treating the flow and the contaminant models separately while intertwining a pair of distinct EnKFs, one for each model. The presented strategy only deals with the estimation of state variables but it can also be used for state and parameter estimation problems. This EnKF-based dual state-state estimation procedure presents a number of novel features: (i) it allows for simultaneous estimation of both flow and contaminant states in parallel; (ii) it provides a time consistent sequential updating scheme between the two models (first flow, then transport); (iii) it simplifies the implementation of the filtering system; and (iv) it yields more stable and accurate solutions than does the standard joint approach. We conducted synthetic numerical experiments based on various time stepping and observation strategies to evaluate the dual EnKF approach and compare its performance with the joint state augmentation approach. Experimental results show that on average, the dual strategy could reduce the estimation error of the coupled states by 15% compared with the

  20. A multiscale fixed stress split iterative scheme for coupled flow and poromechanics in deep subsurface reservoirs

    Science.gov (United States)

    Dana, Saumik; Ganis, Benjamin; Wheeler, Mary F.

    2018-01-01

    In coupled flow and poromechanics phenomena representing hydrocarbon production or CO2 sequestration in deep subsurface reservoirs, the spatial domain in which fluid flow occurs is usually much smaller than the spatial domain over which significant deformation occurs. The typical approach is to either impose an overburden pressure directly on the reservoir thus treating it as a coupled problem domain or to model flow on a huge domain with zero permeability cells to mimic the no flow boundary condition on the interface of the reservoir and the surrounding rock. The former approach precludes a study of land subsidence or uplift and further does not mimic the true effect of the overburden on stress sensitive reservoirs whereas the latter approach has huge computational costs. In order to address these challenges, we augment the fixed-stress split iterative scheme with upscaling and downscaling operators to enable modeling flow and mechanics on overlapping nonmatching hexahedral grids. Flow is solved on a finer mesh using a multipoint flux mixed finite element method and mechanics is solved on a coarse mesh using a conforming Galerkin method. The multiscale operators are constructed using a procedure that involves singular value decompositions, a surface intersections algorithm and Delaunay triangulations. We numerically demonstrate the convergence of the augmented scheme using the classical Mandel's problem solution.

  1. Phenylketonuria Scientific Review Conference : State of the science and future research needs

    NARCIS (Netherlands)

    Camp, Kathryn M.; Parisi, Melissa A.; Acosta, Phyllis B.; Berry, Gerard. T.; Bilder, Deborah A.; Blau, Nenad; Bodamer, Olaf A.; Brosco, Jeffrey P.; Brown, Christine S.; Burlina, Alberto B.; Burton, Barbara K.; Chang, Christine S.; Coates, Paul M.; Cunningham, Amy C.; Dobrowolski, Steven F.; Ferguson, John H.; Franklin, Thomas D.; Frazier, Dianne M.; Grange, Dorothy K.; Greene, Carol L.; Groft, Stephen C.; Harding, Cary O.; Howell, R. Rodney; Huntington, Kathleen L.; Hyatt-Knorr, Henrietta D.; Jevaji, Indira P.; Levy, Harvey L.; Lichter-Konecki, Uta; Lindegren, Mary Lou; Lloyd-Puryear, Michele A.; Matalon, Kimberlee; MacDonald, Anita; McPheeters, Melissa L.; Mitchell, John J.; Mofidi, Shideh; Moseley, Kathryn D.; Mueller, Christine M.; Mulberg, Andrew E.; Nerurkar, Lata S.; Ogata, Beth N.; Pariser, Anne R.; Prasad, Suyash; Pridjian, Gabriella; Rasmussen, Sonja A.; Reddy, Uma M.; Rohr, Frances J.; Singh, Rani H.; Sirrs, Sandra M.; Stremer, Stephanie E.; Tagle, Danilo A.; Thompson, Susan M.; Urv, Tiina K.; Utz, Jeanine R.; van Spronsen, Francjan; Vockley, Jerry; Waisbren, Susan E.; Weglicki, Linda S.; White, Desiree A.; Whitley, Chester B.; Wilfond, Benjamin S.; Yannicelli, Steven; Young, Justin M.

    New developments in the treatment and management of phenylketonuria (PKU) as well as advances in molecular testing have emerged since the National Institutes of Health 2000 PKU Consensus Statement was released. An NIH State-of-the-Science Conference was convened in 2012 to address new findings,

  2. Advances in interpretation of subsurface processes with time-lapse electrical imaging

    Science.gov (United States)

    Singha, Kaminit; Day-Lewis, Frederick D.; Johnson, Tim B.; Slater, Lee D.

    2015-01-01

    Electrical geophysical methods, including electrical resistivity, time-domain induced polarization, and complex resistivity, have become commonly used to image the near subsurface. Here, we outline their utility for time-lapse imaging of hydrological, geochemical, and biogeochemical processes, focusing on new instrumentation, processing, and analysis techniques specific to monitoring. We review data collection procedures, parameters measured, and petrophysical relationships and then outline the state of the science with respect to inversion methodologies, including coupled inversion. We conclude by highlighting recent research focused on innovative applications of time-lapse imaging in hydrology, biology, ecology, and geochemistry, among other areas of interest.

  3. Dynamic coupling of subsurface and seepage flows solved within a regularized partition formulation

    Science.gov (United States)

    Marçais, J.; de Dreuzy, J.-R.; Erhel, J.

    2017-11-01

    Hillslope response to precipitations is characterized by sharp transitions from purely subsurface flow dynamics to simultaneous surface and subsurface flows. Locally, the transition between these two regimes is triggered by soil saturation. Here we develop an integrative approach to simultaneously solve the subsurface flow, locate the potential fully saturated areas and deduce the generated saturation excess overland flow. This approach combines the different dynamics and transitions in a single partition formulation using discontinuous functions. We propose to regularize the system of partial differential equations and to use classic spatial and temporal discretization schemes. We illustrate our methodology on the 1D hillslope storage Boussinesq equations (Troch et al., 2003). We first validate the numerical scheme on previous numerical experiments without saturation excess overland flow. Then we apply our model to a test case with dynamic transitions from purely subsurface flow dynamics to simultaneous surface and subsurface flows. Our results show that discretization respects mass balance both locally and globally, converges when the mesh or time step are refined. Moreover the regularization parameter can be taken small enough to ensure accuracy without suffering of numerical artefacts. Applied to some hundreds of realistic hillslope cases taken from Western side of France (Brittany), the developed method appears to be robust and efficient.

  4. State of the Science White Paper: Effects of Plastics Pollution on Aquatic Life and Aquatic-Dependent Wildlife

    Science.gov (United States)

    This document is a state-of-the-science review – one that summarizes available scientific information on the effects of chemicals associated with plastic pollution and their potential impacts on aquatic life and aquatic-dependent wildlife.

  5. Effect of HRT on nitrogen removal in a coupled HRP and unplanted subsurface flow gravel bed constructed wetland

    Science.gov (United States)

    Mayo, A. W.; Mutamba, J.

    This paper discusses the effect of hydraulic retention time (HRT) on nitrogen removal in a coupled high rate pond (HRP) and a gravel bed subsurface constructed wetland (SSCW) wastewater treatment plant. A pilot plant consisting of a high rate pond (HRT) coupled to an unplanted gravel bed subsurface constructed wetland (SSCW) was used to investigate nitrogen removal from domestic wastewater at the University of Dar es Salaam. The influent, which is predominantly of domestic origin, was drawn from the facultative pond unit of the university’s waste stabilisation pond system. The pilot plant’s HRP unit, which was 0.6 m deep, was designed to nitrify the influent while SSCW unit, which was filled to 10 cm above water level with 19-mm diameter aggregates, was predominantly anoxic and promoted denitrification. The study was conducted at two different operational settings. In Phase 1, both the HRP and the SSCW units had a retention time of 5 days. During Phase 2, the hydraulic retention time in HRP was increased to 8 days while the retention time of the SSCW unit was maintained at 5 days. Samples were collected daily for laboratory analysis of influent and effluent wastewater quality. All experiments were conducted in accordance with Standard Methods. The results showed that improved nitrogen removal occurred with increase in hydraulic time of the HRP unit. In Phase 1 an average nitrogen removal of 33% was achieved while removal efficiency improved to 43% in Phase 2. It was also revealed that the HRP can effectively be used to promote nitrification and the unplanted gravel bed subsurface constructed wetland can be used as a denitrifying unit.

  6. A Collaborative State of the Science Initiative: Transforming Moral Distress into Moral Resilience in Nursing.

    Science.gov (United States)

    Rushton, Cynda Hylton; Schoonover-Shoffner, Kathy; Kennedy, Maureen Shawn

    2017-02-01

    : To examine practices for addressing moral distress, a collaborative project was developed by the Johns Hopkins Berman Institute of Bioethics, the Johns Hopkins School of Nursing, the American Journal of Nursing, and the Journal of Christian Nursing, along with the American Association of Critical-Care Nurses and the American Nurses Association. Its purpose was to identify strategies that individuals and systems can use to mitigate the detrimental effects of moral distress and foster moral resilience. On August 11 and 12, 2016, an invitational symposium, State of the Science: Transforming Moral Distress into Moral Resilience in Nursing, was held at the Johns Hopkins School of Nursing in Baltimore, Maryland. Forty-five nurse clinicians, researchers, ethicists, organization representatives, and other stakeholders took part. The result of the symposium was group consensus on recommendations for addressing moral distress and building moral resilience in four areas: practice, education, research, and policy. Participants and the organizations represented were energized and committed to moving this agenda forward.

  7. Coupled surface and subsurface flow modeling of natural hillslopes in the Aburrá Valley (Medellín, Colombia)

    Science.gov (United States)

    Blessent, Daniela; Barco, Janet; Temgoua, André Guy Tranquille; Echeverrri-Ramirez, Oscar

    2017-03-01

    Numerical results are presented of surface-subsurface water modeling of a natural hillslope located in the Aburrá Valley, in the city of Medellín (Antioquia, Colombia). The integrated finite-element hydrogeological simulator HydroGeoSphere is used to conduct transient variably saturated simulations. The objective is to analyze pore-water pressure and saturation variation at shallow depths, as well as volumes of water infiltrated in the porous medium. These aspects are important in the region of study, which is highly affected by soil movements, especially during the high-rain seasons that occur twice a year. The modeling exercise considers rainfall events that occurred between October and December 2014 and a hillslope that is currently monitored because of soil instability problems. Simulation results show that rainfall temporal variability, mesh resolution, coupling length, and the conceptual model chosen to represent the heterogeneous soil, have a noticeable influence on results, particularly for high rainfall intensities. Results also indicate that surface-subsurface coupled modeling is required to avoid unrealistic increase in hydraulic heads when high rainfall intensities cause top-down saturation of soil. This work is a first effort towards fostering hydrogeological modeling expertise that may support the development of monitoring systems and early landslide warning in a country where the rainy season is often the cause of hydrogeological tragedies associated with landslides, mud flow or debris flow.

  8. Sources of information influencing the state-of-the-science gap in hormone replacement therapy usage.

    Directory of Open Access Journals (Sweden)

    Fiona Chew

    Full Text Available Medical reviews and research comprise a key information source for news media stories on medical therapies and innovations as well as for physicians in updating their practice. The present study examined medical review journal articles, physician surveys and news media coverage of hormone replacement therapy (HT to assess the relationship between the three information sources and whether/if they contributed to a state-of-the-science gap (a condition when the evaluation of a medical condition or therapy ascertained by the highest standards of investigation is incongruent with the science-in-practice such as physician recommendations and patient actions.We content-analyzed 177 randomly sampled HT medical reviews between 2002 and 2014, and HT news valence in three major TV networks, newspapers and magazines/internet sites in 2002-2003, 2008-2009 and 2012-14. The focus in both analyses was whether HT benefits outweighed risks, risks outweighed benefits or both risks and benefits were presented. We also qualitatively content-analyzed all 19 surveys of US physicians' HT recommendations from 2002 to 2009, and 2012 to 2014.Medical reviews yielded a mixed picture about HT (40.1% benefits, 26.0% risks, and 33.9% both benefits and risks. While a majority of physician surveys were pro-HT 10/19, eight showed varied attitudes and one was negative. Newspaper and television coverage reflected a pro and con balance while magazine stories were more positive in the later reporting period.Medical journal review articles, physicians, and media reports all provide varying view points towards hormone therapy use thus leading to limited knowledge about the actual risks and benefits of HT among peri- and menopausal women and a state-of-the-science gap.

  9. Sources of information influencing the state-of-the-science gap in hormone replacement therapy usage.

    Science.gov (United States)

    Chew, Fiona; Wu, Xianwei

    2017-01-01

    Medical reviews and research comprise a key information source for news media stories on medical therapies and innovations as well as for physicians in updating their practice. The present study examined medical review journal articles, physician surveys and news media coverage of hormone replacement therapy (HT) to assess the relationship between the three information sources and whether/if they contributed to a state-of-the-science gap (a condition when the evaluation of a medical condition or therapy ascertained by the highest standards of investigation is incongruent with the science-in-practice such as physician recommendations and patient actions). We content-analyzed 177 randomly sampled HT medical reviews between 2002 and 2014, and HT news valence in three major TV networks, newspapers and magazines/internet sites in 2002-2003, 2008-2009 and 2012-14. The focus in both analyses was whether HT benefits outweighed risks, risks outweighed benefits or both risks and benefits were presented. We also qualitatively content-analyzed all 19 surveys of US physicians' HT recommendations from 2002 to 2009, and 2012 to 2014. Medical reviews yielded a mixed picture about HT (40.1% benefits, 26.0% risks, and 33.9% both benefits and risks). While a majority of physician surveys were pro-HT 10/19), eight showed varied attitudes and one was negative. Newspaper and television coverage reflected a pro and con balance while magazine stories were more positive in the later reporting period. Medical journal review articles, physicians, and media reports all provide varying view points towards hormone therapy use thus leading to limited knowledge about the actual risks and benefits of HT among peri- and menopausal women and a state-of-the-science gap.

  10. Hydraulic characterization of rocky subsurface using field infiltrometer measurements coupled with hydrogeophysical investigations

    Science.gov (United States)

    Caputo, M. C.; de Carlo, L.; de Benedictis, F.; Vurro, M.

    2009-04-01

    The shallow and/or karstic and fractured aquifers are among the most important water resources. At the same time, they are particularly vulnerable to contamination. A detailed scientific knowledge of the behavior of these aquifers is essential for the development of sustainable groundwater management. Different investigation methods have been developed with the aim to characterize the subsurface and to monitor the flow and solute transport in these hydrogeology systems. This study presents the results of an investigation method, that combine large infiltrometer measurements with elettrical resistivity profiles, carried out in two different experimental sites characterized by different hydrogeology systems. One site, close to Altamura a city in the South of Italy, is represented from karstic and fractured limestone that overlays the deep aquifer. This area has been affected by sludge waste deposits derived from municipal and industrial wastewater treatment plants. The second site, close to San Pancrazio Salentino town in Southern Italy also, is represented from a quarry of calcarenite that has been used as a dump of sludge of mycelium producted from pharmaceutical industry. In both these cases the waste disposal have caused soil-subsoil contamination. Knowledge of the flow rate of the unsaturated zone percolation is needed to investigate the vertical migration of pollutants and the vulnerability of the aquifers. In this study, subsurface electrical resistivity measurements were used to visualize the infiltration of water in the subsoil due to unsaturated water flow. Simultaneously, the vertical flow was investigated by measuring water levels during infiltrometer tests carried out using a large adjustable ring infiltrometer, designed to be installed in the field directly on the outcrop of rock. In addition electrical resistivity azimuthal surveys have been conducted to detect principal fractures strike directions that cause preferential flow. The results obtained

  11. mobilityRERC state of the science: How science influences public policy in seating and mobility.

    Science.gov (United States)

    Hostak, Rita S; Edwards, Doran; Sprigle, Stephen

    2013-11-01

    In the United States (US), wheeled mobility and seating equipment is classified as Durable Medical Equipment (DME). DME includes a wide array of devices including canes, walkers, home oxygen equipment, hospital beds, and wheelchairs. Seating and mobility devices reflect a wide range of DME, from relatively simple standard manual wheelchairs and cushions to highly complex manual and power wheelchairs and custom seating systems. This wide range of complexity results in a wide range of policies that govern the provision of seating and mobility equipment. This article results from a presentation during the Wheeled Mobility Rehabilitation Engineering Research Center's (RERC's) State of the Science Conference in 2012. The presentation was designed to proffer key concepts related to coverage policies and policy decision-making. Topics covered include an introduction to key policy issues impacting seating and mobility equipment, a description of the barriers that prevent or hinder research being used to inform coverage policy decisions, discussion of the challenges surrounding evidence-based policy decisions regarding seating and mobility, and suggestions of strategies for including policy makers and other stakeholders in setting research priorities and in reporting research findings. In the United States, wheeled mobility and seating equipment are classified as Durable Medical Equipments which are governed by a wide range of policies. Researchers should be encouraged to supplement research articles with articles that explicitly address clinical and policy implications of the work. Policy-makers should be encouraged to engage researchers to insure the breadth of knowledge and evidence is represented and understood.

  12. The state of the science of emotional intelligence related to nursing leadership: an integrative review.

    Science.gov (United States)

    Akerjordet, Kristin; Severinsson, Elisabeth

    2010-05-01

    To explore the state of the science of emotional intelligence (EI) related to nursing leadership and its critiques. The phenomenon of EI has emerged as a potential new construct of importance for nursing leadership that enhances educational, organizational, staff and patient outcomes. Nevertheless, important questions and critical reflections related to exaggerated claims, conceptualizations and measurements exist. A literature search was conducted using international databases covering the period January 1999 to December 2009. A manual search of relevant journals and significant references increased the data. Critical reflection seems to be associated with the unsubstantiated predictive validity of EI in the area of nursing leadership. In addition, important moral issues are called into question. It is important to possess in-depth knowledge of EI and its scientific critique when integrating the concept into nursing research, education and practical settings. More attention to the nature of emotion in EI is necessary. Implications for nursing leadership The dynamics of EI should be explored in the context of both the surrounding environment and individual differences, as the latter can be adaptive in some settings but harmful in others.

  13. State of the Science of Spirituality and Palliative Care Research Part I: Definitions, Measurement, and Outcomes.

    Science.gov (United States)

    Steinhauser, Karen E; Fitchett, George; Handzo, George F; Johnson, Kimberly S; Koenig, Harold G; Pargament, Kenneth I; Puchalski, Christina M; Sinclair, Shane; Taylor, Elizabeth J; Balboni, Tracy A

    2017-09-01

    The State of the Science in Spirituality and Palliative Care was convened to address the current landscape of research at the intersection of spirituality and palliative care and to identify critical next steps to advance this field of inquiry. Part I of the SOS-SPC two-part series focuses on questions of 1) What is spirituality? 2) What methodological and measurement issues are most salient for research in palliative care? And 3) What is the evidence relating spirituality and health outcomes? After describing current evidence we make recommendations for future research in each of the three areas of focus. Results show wide variance in the ways spirituality is operationalized and the need for definition and conceptual clarity in research in spirituality. Furthermore, the field would benefit from hypothesis-driven outcomes research based on a priori specification of the spiritual dimensions under investigation and their longitudinal relationship with key palliative outcomes, the use of validated measures of predictors and outcomes, and rigorous assessment of potential confounding variables. Finally, results highlight the need for research in more diverse populations. Published by Elsevier Inc.

  14. Developmental programming: State-of-the-science and future directions-summary from a Pennington biomedical symposium

    Science.gov (United States)

    On December 8-9, 2014, the Pennington Biomedical Research Center convened a scientific symposium to review the state-of-the-science and future directions for the study of developmental programming of obesity and chronic disease. The objectives of the symposium were to discuss: (i) past and current s...

  15. 2015 proceedings of the National Heart, Lung, and Blood Institute's State of the Science in Transfusion Medicine symposium

    NARCIS (Netherlands)

    Spitalnik, Steven L.; Triulzi, Darrell; Devine, Dana V.; Dzik, Walter H.; Eder, Anne F.; Gernsheimer, Terry; Josephson, Cassandra D.; Kor, Daryl J.; Luban, Naomi L. C.; Roubinian, Nareg H.; Mondoro, Traci; Welniak, Lisbeth A.; Zou, Shimian; Glynn, Simone; Hendrickson, Jeanne; Zimring, James C.; Yazdanbakhsh, Karina; Delaney, Megan; Ware, Russell E.; Tinmouth, Alan; Doctor, Allan; Migliaccio, Anna Rita; Fergusson, Dean A.; Widness, John A.; Carson, Jeffrey L.; Hess, John; Roback, John D.; Waters, Jonathan H.; Cancelas, Jose A.; Gladwin, Mark T.; Rogers, Mary A. M.; Ness, Paul M.; Rao, Sunil; Watkins, Timothy R.; Spinella, Philip C.; Kaufman, Richard M.; Slichter, Sherrill J.; McCullough, Jeffrey; Blumberg, Neil; Webert, Kathryn E.; Fitzpatrick, Michael; Shander, Aryeh; Corash, Laurence M.; Murphy, Michael; Silberstein, Leslie E.; Dumont, Larry J.; Mitchell, W. Beau; Macdonald, Victor W.; Hoffmeister, Karin M.; Italiano, Joseph E.; Gupta, Anirban Sen; Wu, Yanyun; Cap, Andrew P.; Li, Renhao; Goodrich, Raymond P.; Morrell, Craig N.; Semple, John W.; Kahr, Walter H. A.; Tanaka, Ken; Haas, Thorsten; Sperry, Jason L.; Callum, Jeannie L.; Porte, Robert J.; Mallett, Sue; Gajic, Ognjen; Juffermans, Nicole P.; Karam, Oliver; Vlaar, Alexander P. J.; Looney, Mark R.; Inaba, Ken; Shaz, Beth H.; Hunt, Beverly J.; Cohen, Mitchell J.; Kitchens, Craig S.; Stanworth, Simon J.; Bryant, Barbara J.; Kiss, Joseph E.; Busch, Michael P.; Dodd, Roger Y.; Heddle, Nancy M.; Spencer, Bryan R.; Keller, Anthony J.; Germain, Marc; Goldman, Mindy; Tomasulo, Peter A.; de Kort, Wim; Mast, Alan E.; Francis, Richard O.

    2015-01-01

    On March 25 and 26, 2015, the National Heart, Lung, and Blood Institute sponsored a meeting on the State of the Science in Transfusion Medicine on the National Institutes of Health (NIH) campus in Bethesda, Maryland, which was attended by a diverse group of 330 registrants. The meeting's goal was to

  16. State of the science on implant dentistry: a workshop developed using an evidence-based approach.

    Science.gov (United States)

    Iacono, Vincent J; Cochran, David L

    2007-01-01

    This overview was prepared to describe how an evidence-based approach was used to develop an Academy of Osseointegration (AO) Workshop on the State of the Science on Implant Dentistry (SSID). An AO SSID Workshop Planning Committee was appointed in 2001 to follow an evidence-based approach for reviewing published clinical data using strict inclusion and exclusion criteria in order to answer 8 closed-end 4-part clinical questions. A systematic approach was employed to assure coherent data management and analysis. Reviewers, co-reviewers, and a biostatistician were appointed. The workshop agenda was developed to include participants who had the primary responsibility for each of the 8 workshop sections to answer 5 consensus questions for the section's systematic review. The planned outcomes of the SSID Workshop included publication of the 8 consensus reports with their respective systematic reviews in The International Journal of Oral & Maxillofacial Implants (supplemental issue), 2007; the development of clinical guidelines responding to each of the 8 focused questions; and the identification and prioritization of questions or topics requiring further research. The evidence-based approach was utilized successfully in planning and carrying out the AO SSID Workshop held on August 3-6, 2006, in Oak Brook, Illinois, and the subsequent publication of its proceedings. Although successful in its objectives, the outcome of systematic reviews is only as good as the published data. Significant deficiencies in published implant studies were identified, including, but not limited to, a lack of randomized controlled prospective clinical trials, universal acceptance and publication of defined implant survival and success criteria, and clear questions with well-defined research design. The evidence-based approach can be used to systematically review the literature for a workshop on important questions related to implant dentistry. A major limitation is the lack of common outcome

  17. State of the science of maternal-infant bonding: a principle-based concept analysis.

    Science.gov (United States)

    Bicking Kinsey, Cara; Hupcey, Judith E

    2013-12-01

    to provide a principle-based analysis of the concept of maternal-infant bonding. principle-based method of concept analysis for which the data set included 44 articles published in the last decade from Pubmed, CINAHL, and PyschINFO/PsychARTICLES. literature inclusion criteria were English language, articles published in the last decade, peer-reviewed journal articles and commentary on published work, and human populations. after a brief review of the history of maternal-infant bonding, a principle-based concept analysis was completed to examine the state of the science with regard to this concept. The concept was critically examined according to the clarity of definition (epistemological principle), applicability of the concept (pragmatic principle), consistency in use and meaning (linguistic principle), and differentiation of the concept from related concepts (logical principle). Analysis of the concept revealed: (1) Maternal-infant bonding describes maternal feelings and emotions towards her infant. Evidence that the concept encompasses behavioural or biological components was limited. (2) The concept is clearly operationalised in the affective domain. (3) Maternal-infant bonding is linguistically confused with attachment, although the boundaries between the concepts are clearly delineated. despite widespread use of the concept, maternal-infant bonding is at times superficially developed and subject to confusion with related concepts. Concept clarification is warranted. A theoretical definition of the concept of maternal-infant bonding was developed to aid in the clarification, but more research is necessary to further clarify and advance the concept. nurse midwives and other practitioners should use the theoretical definition of maternal-infant bonding as a preliminary guide to identification and understanding of the concept in clinical practice. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Fire effects on aquatic ecosystems: an assessment of the current state of the science

    Science.gov (United States)

    Rebecca J. Bixby,; Scott D. Cooper,; Gresswell, Bob; Lee E. Brown,; Clifford N. Dahm,; Kathleen A. Dwire,

    2015-01-01

    Fire is a prevalent feature of many landscapes and has numerous and complex effects on geological, hydrological, ecological, and economic systems. In some regions, the frequency and intensity of wildfire have increased in recent years and are projected to escalate with predicted climatic and landuse changes. In addition, prescribed burns continue to be used in many parts of the world to clear vegetation for development projects, encourage desired vegetation, and reduce fuel loads. Given the prevalence of fire on the landscape, authors of papers in this special series examine the complexities of fire as a disturbance shaping freshwater ecosystems and highlight the state of the science. These papers cover key aspects of fire effects that range from vegetation loss and recovery in watersheds to effects on hydrology and water quality with consequences for communities (from algae to fish), food webs, and ecosystem processes (e.g., organic matter subsidies, nutrient cycling) across a range of scales. The results presented in this special series of articles expand our knowledge of fire effects in different biomes, water bodies, and geographic regions, encompassing aquatic population, community, and ecosystem responses. In this overview, we summarize each paper and emphasize its contributions to knowledge on fire ecology and freshwater ecosystems. This overview concludes with a list of 7 research foci that are needed to further our knowledge of fire effects on aquatic ecosystems, including research on: 1) additional biomes and geographic regions; 2) additional habitats, including wetlands and lacustrine ecosystems; 3) different fire severities, sizes, and spatial configurations; and 4) additional response variables (e.g., ecosystem processes) 5) over long (>5 y) time scales 6) with more rigorous study designs and data analyses, and 7) consideration of the effects of fire management practices and policies on aquatic ecosystems.

  19. Coupled Land Surface-Subsurface Inverse Modeling to Investigate Arctic Hydrological and Thermal Dynamics and Soil Organic Content using Geophysical Data

    Science.gov (United States)

    Tran, A. P.; Dafflon, B.; Hubbard, S. S.

    2016-12-01

    Quantification of soil surface-subsurface hydro-thermal processes in permafrost regions is essential as they influence many biogeochemical processes. Recently, coupled hydrogeophysical inversion that inverts geophysical data to estimate subsurface hydro-thermal properties and processes has become an important approach. However, this approach is suffered from non-uniqueness because it typically relies on only geophysical datasets. This approach is also focuses on quantifying subsurface processes only. We extend previous coupled hydrogeophysical inversion approach to include multiple types of above- and below-ground datasets, and also to account for interactions between the land and subsurface. The joint inversion of multiple geophysical and non-geophysical datasets helps to reduce non-uniqueness. We focus our study in the Artic region, where surface-subsurface hydro-thermal regimes are both influenced by soil organic carbon and mineral content. In our inversion scheme, the CLM model serves as a forward model to simulate the land-surface processes and subsurface hydro-thermal dynamics. We developed an advanced optimization technique that combines the deterministic and stochastic optimization algorithms to obtain both model parameters and their uncertainties. The stochastic optimization estimates the posterior distribution (pdf) of the model parameters by using the Bayesian inference and Delayed Rejection Adaptive Metropolis (DRAM) Markov Chain Monte Carlo (MCMC) techniques. The deterministic optimization algorithm is used to approximate the start point of model parameters and proposal covariance matrix for the stochastic optimization. We will describe the new coupled inversion approach and its ability to provide accurate estimates of soil hydro-thermal and physical properties, the latter including vertical distribution of organic, clay and sand content. We will also describe analysis of the modeling results, including: 1) evaluation of the relationship between

  20. Summary report on close-coupled subsurface barrier technology: Initial field trials to full-scale demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Heiser, J.H. [Brookhaven National Lab., Upton, NY (United States). Environmental and Waste Technology Center; Dwyer, B. [Sandia National Lab., Albuquerque, NM (United States)

    1997-09-01

    The primary objective of this project was to develop and demonstrate the installation and measure the performance of a close-coupled barrier for the containment of subsurface waste or contaminant migration. A close-coupled barrier is produced by first installing a conventional, low-cost, cement-grout containment barrier followed by a thin lining of a polymer grout. The resultant barrier is a cement-polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. The technology has matured from a regulatory investigation of the issues concerning the use of polymers to laboratory compatibility and performance measurements of various polymer systems to a pilot-scale, single column injection at Sandia to full-scale demonstration. The feasibility of the close-coupled barrier concept was proven in a full-scale cold demonstration at Hanford, Washington and then moved to the final stage with a full-scale demonstration at an actual remediation site at Brookhaven National Laboratory (BNL). At the Hanford demonstration the composite barrier was emplaced around and beneath a 20,000 liter tank. The secondary cement layer was constructed using conventional jet grouting techniques. Drilling was completed at a 45{degree} angle to the ground, forming a cone-shaped barrier. The primary barrier was placed by panel jet-grouting with a dual-wall drill stem using a two part polymer grout. The polymer chosen was a high molecular weight acrylic. At the BNL demonstration a V-trough barrier was installed using a conventional cement grout for the secondary layer and an acrylic-gel polymer for the primary layer. Construction techniques were identical to the Hanford installation. This report summarizes the technology development from pilot- to full-scale demonstrations and presents some of the performance and quality achievements attained.

  1. Modelling the effects of tides and storm surges on coastal aquifers using a coupled surface-subsurface approach.

    Science.gov (United States)

    Yang, Jie; Graf, Thomas; Herold, Maria; Ptak, Thomas

    2013-06-01

    Coastal aquifers are complex hydrologic systems because many physical processes interact: (i) variably saturated flow, (ii) spatial-temporal fluid density variations, (iii) tidal fluctuations, (iv) storm surges overtopping dykes, and (v) surface runoff of storm water. The HydroGeoSphere model is used to numerically simulate coastal flow dynamics, assuming a fully coupled surface-subsurface approach, accounting for all processes listed above. The diffusive wave approximation of the St. Venant equation is used to describe surface flow. Surface flow and salt transport are fully coupled with subsurficial variably saturated, variable-density flow and salt transport through mathematical terms that represent exchange of fluid mass and solute mass, respectively. Tides and storm surges induce a time-variant head that is applied to nodes of the surface domain. The approach is applied to real cases of tide and storm surge events. Tide simulation results confirm the existence of a recirculating zone, forming beneath the upper part of the intertidal zone. By monitoring the exchange fluid flux rates through the beach, it was found that the major inflow to the aquifer takes place at the upper part of the intertidal zone, which explains the formation of the recirculating zone. The recirculating zone is forming particularly during rising tide. Results from a storm surge simulation show that plume fingers develop below the flooded land surface. Natural remediation by seaward flowing freshwater is relatively slow, such that reducing the salt concentration in the aquifer down to drinking water standards takes up to 10 years. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Improving animal welfare and reducing animal use for veterinary vaccine potency testing: state of the science and future directions

    OpenAIRE

    STOKES William; BROWN Karen; KULPA-EDDY Jodie; SRINIVAS Geetha; HALDER Maria; DRAAYER Hans; GALVIN Jeffrey; CLAASEN Ivo; GIFFORD Glen; WOODLAND Ralph; DOELLING Vivian; JONES Brett

    2011-01-01

    Veterinary vaccines contribute to improved human and animal health and welfare by preventing diseases and deaths caused by a wide range of infectious agents. However, testing necessary to ensure vaccine effectiveness and safety can involve large numbers of animals and significant pain and distress. NICEATM and ICCVAM convened an international workshop to review the state of the science of human and veterinary vaccine potency and safety testing methods and to identify opportunities to advance ...

  3. 76 FR 40736 - NIH State-of-the-Science Conference on the Role of Active Surveillance in the Management of Men...

    Science.gov (United States)

    2011-07-11

    ... HUMAN SERVICES National Institutes of Health NIH State-of-the-Science Conference on the Role of Active Surveillance in the Management of Men With Localized Prostate Cancer ACTION: Notice. Notice is hereby given of the National Institutes of Health (NIH), ``State-of-the-Science Conference on the Role of Active...

  4. NIH State-of-the-Science Conference Statement on management of menopause-related symptoms.

    Science.gov (United States)

    women need safe and effective treatment. It is difficult to differentiate those symptoms that are truly associated with menopause from those due to aging. Hot flashes, night sweats, and vaginal dryness are clearly tied to the menopausal transition, and there is some positive evidence of a menopausal link for sleep disturbance. Vasomotor symptoms are reported with high frequency during the menopausal transition. Estrogen, either by itself or with progestins, is the most consistently effective therapy for these symptoms. However, the Women's Health Initiative (WHI) has identified important risk factors associated with use of these therapies. Decision making for women regarding treatment for menopausal symptoms requires personal knowledge and balancing of these risks. There are many potential alternatives to estrogen. However, their effectiveness and long-term safety need to be studied in rigorous clinical trials in diverse populations of women. Much more research is needed to clearly define the natural history of menopause, associated symptoms, and effectiveness and safety of treatments for bothersome symptoms. Natural histories are important for both science and policy. Knowing how many women transit menopause with few or no symptoms, and how many manage menopause largely on their own, can lead to public health information that empowers women and increases their self-reliance. Medical care and future clinical trials are best focused on women with the most severe and prolonged symptoms. The state of the science in management of menopausal symptoms should be reassessed periodically. Menopause is "medicalized" in contemporary U.S. society. There is great need to develop and disseminate information that emphasizes menopause as a normal, healthy phase of women's lives and promotes its demedicalization. Medical care and future clinical trials are best focused on women with the most severe and prolonged symptoms. Barriers to professional care for these women should be removed.

  5. Coupling a three-dimensional subsurface flow and transport model with a land surface model to simulate stream-aquifer-land interactions (CP v1.0)

    Science.gov (United States)

    Bisht, Gautam; Huang, Maoyi; Zhou, Tian; Chen, Xingyuan; Dai, Heng; Hammond, Glenn E.; Riley, William J.; Downs, Janelle L.; Liu, Ying; Zachara, John M.

    2017-12-01

    A fully coupled three-dimensional surface and subsurface land model is developed and applied to a site along the Columbia River to simulate three-way interactions among river water, groundwater, and land surface processes. The model features the coupling of the Community Land Model version 4.5 (CLM4.5) and a massively parallel multiphysics reactive transport model (PFLOTRAN). The coupled model, named CP v1.0, is applied to a 400 m × 400 m study domain instrumented with groundwater monitoring wells along the Columbia River shoreline. CP v1.0 simulations are performed at three spatial resolutions (i.e., 2, 10, and 20 m) over a 5-year period to evaluate the impact of hydroclimatic conditions and spatial resolution on simulated variables. Results show that the coupled model is capable of simulating groundwater-river-water interactions driven by river stage variability along managed river reaches, which are of global significance as a result of over 30 000 dams constructed worldwide during the past half-century. Our numerical experiments suggest that the land-surface energy partitioning is strongly modulated by groundwater-river-water interactions through expanding the periodically inundated fraction of the riparian zone, and enhancing moisture availability in the vadose zone via capillary rise in response to the river stage change. Meanwhile, CLM4.5 fails to capture the key hydrologic process (i.e., groundwater-river-water exchange) at the site, and consequently simulates drastically different water and energy budgets. Furthermore, spatial resolution is found to significantly impact the accuracy of estimated the mass exchange rates at the boundaries of the aquifer, and it becomes critical when surface and subsurface become more tightly coupled with groundwater table within 6 to 7 meters below the surface. Inclusion of lateral subsurface flow influenced both the surface energy budget and subsurface transport processes as a result of river-water intrusion into the

  6. Subsurface Reactive Transport Modelling of the Lateritic Ni mineralization in New Caledonia: A coupled Thermo-Hydro-Geochemical Approach

    Science.gov (United States)

    Myagkiy, Andrey; Golfier, Fabrice; Truche, Laurent; Cathelineau, Michel

    2017-04-01

    This research proposes a subsurface reactive geochemical transport modelling of the development of a nickel laterite profile in New Caledonia over the past few million years. Such a regolith formation from ultramafic bedrock was not yet modelled and gives new profound insights into the Ni vertical mobility, its retention processes in a soil profile and relative enrichment, that are still poorly studied. The downward progression of the lateritization front is allowed by the leaching of the soluble elements (Si, Mg and Ni) through drainage system, represented by porous column of peridotite. Particular emphasis is placed on the detailed understanding of Ni redistribution as a function of time and depth triggered by Ni-bearing silicate precipitation (i.e. garnierite) and by sorption or recrystallization process with goethite. Current work consists of the following models: i) 1-D calculations that are done at 25oC with the code PHREEQC associated with the llnl thermodynamic database and ii) 2-D model that handles coupled thermo-hydro-chemical processes and is calculated on the interface Comsol-Phreeqc (iCP, Nardi et al., 2014). The impact of i) fluid flow in fractures and ii) recharge rate along with iii) hydraulic and iv) geothermal gradients are considered here. While the first model gives profound insights into the vertical mobility of metals upon the formation of laterite (Myagkiy et al, submitted), the latter one additionally allows to describe heterogeneities of mineralizing distributions due to the influence of preferential pathways (fractures), convective flows and lateral transfers. Our long-term 1-D simulations (10 Ma) clearly demonstrate that the Ni enrichment and thickening of iron-rich zone are governed by the vertical progression of the pH front. At the same time 2-D modelling shows reactivation of Ni from oxide zone and it subsequent redistribution and concentration in saprolite. Such a model appears to be of importance in attempt of explanation Ni

  7. Feasibility study of a swept frequency electromagnetic probe (SWEEP) using inductive coupling for the determination of subsurface conductivity of the earth and water prospecting in arid regions

    Science.gov (United States)

    Latorraca, G. A.; Bannister, L. H.

    1974-01-01

    Techniques developed for electromagnetic probing of the lunar interior, and techniques developed for the generation of high power audio frequencies were combined to make practical a magnetic inductive coupling system for the rapid measurement of ground conductivity profiles which are helpful when prospecting for the presence and quality of subsurface water. A system which involves the measurement of the direction, intensity, and time phase of the magnetic field observed near the surface of the earth at a distance from a horizontal coil energized so as to create a field that penetrates the earth was designed and studied to deduce the conductivity and stratification of the subsurface. Theoretical studies and a rudimentary experiment in an arid region showed that the approach is conceptually valid and that this geophysical prospecting technique can be developed for the economical exploration of subterranean water resources.

  8. Developmental programming: State-of-the-science and future directions-Summary from a Pennington Biomedical symposium.

    Science.gov (United States)

    Sutton, Elizabeth F; Gilmore, L Anne; Dunger, David B; Heijmans, Bas T; Hivert, Marie-France; Ling, Charlotte; Martinez, J Alfredo; Ozanne, Susan E; Simmons, Rebecca A; Szyf, Moshe; Waterland, Robert A; Redman, Leanne M; Ravussin, Eric

    2016-05-01

    On December 8-9, 2014, the Pennington Biomedical Research Center convened a scientific symposium to review the state-of-the-science and future directions for the study of developmental programming of obesity and chronic disease. The objectives of the symposium were to discuss: (i) past and current scientific advances in animal models, population-based cohort studies, and human clinical trials, (ii) the state-of-the-science of epigenetic-based research, and (iii) considerations for future studies. This symposium provided a comprehensive assessment of the state of the scientific field and identified research gaps and opportunities for future research in order to understand the mechanisms contributing to the developmental programming of health and disease. Identifying the mechanisms which cause or contribute to developmental programming of future generations will be invaluable to the scientific and medical community. The ability to intervene during critical periods of prenatal and early postnatal life to promote lifelong health is the ultimate goal. Considerations for future research including the use of animal models, the study design in human cohorts with considerations about the timing of the intrauterine exposure, and the resulting tissue-specific epigenetic signature were extensively discussed and are presented in this meeting summary. © 2016 The Obesity Society.

  9. Insights in time dependent cross compartment sensitivities from ensemble simulations with the fully coupled subsurface-land surface-atmosphere model TerrSysMP

    Science.gov (United States)

    Schalge, Bernd; Rihani, Jehan; Haese, Barbara; Baroni, Gabriele; Erdal, Daniel; Haefliger, Vincent; Lange, Natascha; Neuweiler, Insa; Hendricks-Franssen, Harrie-Jan; Geppert, Gernot; Ament, Felix; Kollet, Stefan; Cirpka, Olaf; Saavedra, Pablo; Han, Xujun; Attinger, Sabine; Kunstmann, Harald; Vereecken, Harry; Simmer, Clemens

    2017-04-01

    Currently, an integrated approach to simulating the earth system is evolving where several compartment models are coupled to achieve the best possible physically consistent representation. We used the model TerrSysMP, which fully couples subsurface, land surface and atmosphere, in a synthetic study that mimicked the Neckar catchment in Southern Germany. A virtual reality run at a high resolution of 400m for the land surface and subsurface and 1.1km for the atmosphere was made. Ensemble runs at a lower resolution (800m for the land surface and subsurface) were also made. The ensemble was generated by varying soil and vegetation parameters and lateral atmospheric forcing among the different ensemble members in a systematic way. It was found that the ensemble runs deviated for some variables and some time periods largely from the virtual reality reference run (the reference run was not covered by the ensemble), which could be related to the different model resolutions. This was for example the case for river discharge in the summer. We also analyzed the spread of model states as function of time and found clear relations between the spread and the time of the year and weather conditions. For example, the ensemble spread of latent heat flux related to uncertain soil parameters was larger under dry soil conditions than under wet soil conditions. Another example is that the ensemble spread of atmospheric states was more influenced by uncertain soil and vegetation parameters under conditions of low air pressure gradients (in summer) than under conditions with larger air pressure gradients in winter. The analysis of the ensemble of fully coupled model simulations provided valuable insights in the dynamics of land-atmosphere feedbacks which we will further highlight in the presentation.

  10. State of the science: molecular classifications of breast cancer for clinical diagnostics.

    Science.gov (United States)

    Robison, John E; Perreard, Laurent; Bernard, Philip S

    2004-07-01

    Over the past few years, the study of genomics has embarked on developing gene expression-based classifications for tumors-an initiative that promises to revolutionize cancer medicine. High-throughput genomic platforms, such as microarray and SAGE, have found gene expression signatures that correlate to important clinical parameters used in current staging and are providing additional information that will improve standard of care. Although implementing a molecular taxonomy for prognosis and treatment would likely benefit cancer patients, there remain significant obstacles to using these assays within the current diagnostic framework. Since most genomic assays are being performed from fresh tissue, there is a need to either change the practice of formalin-fixing and paraffin-embedding tissue or adapting the assays for use on degraded RNA specimens. To date, even the most mature data sets, such as molecular classifications for breast cancer, still fall short of the number of patients needed to generalize the results to treating large populations. To implement these assays in large scale, there will need to be standardization of sample procurement, preparation, and analysis. Certainly, the greatest improvements in patient care will come through tailored therapies as genomics is coupled with clinical trials that randomize cohorts to different treatments. This manuscript reviews the current standards of care, presents progress that is being made in the development of genomic assays for breast cancer and discusses options for implementing these new tests into the clinical setting.

  11. Investigation of (de)coupling between surface and subsurface soil moisture using a Distributed Lag Non-linear Model (DNLM)

    Science.gov (United States)

    Carranza, Coleen; van der Ploeg, Martine

    2017-04-01

    Accurate estimates of water content in the soil profile are essential for environmental and climate modeling studies. Current trends for estimating profile soil moisture incorporate remote sensing methods for mapping soil moisture at greater spatial coverage but is limited to the upper soil layers (e.g. 5cm for radar satellites). Data assimilation methods offer promising computational techniques to translate mapped surface soil moisture to estimates of profile soil moisture, in conjunction with physical models. However, a variety of factors, such as differences in the drying rates, can lead to "decoupling" (Capehart and Carlson, 1997) of surface and subsurface soil moisture. In other words, surface soil moisture conditions no longer reflect or represent subsurface conditions. In this study, we investigated the relation and observed decoupling between surface and subsurface soil moisture from 15-minute interval time series datasets in four selected Dutch agricultural fields (SM_05, SM_09, SM_13, SM_20) from the soil moisture network in Twente region. The idea is that surface soil moisture conditions will be reflected in the subsurface after a certain time lag because of its movement or flow from the surface. These lagged associations were analysed using distributed lag non-linear model (DLNM). This statistical technique provides a framework to simultaneously represent non-linear exposure-response dependencies and delayed effects. DNLM was applied to elucidate which surface soil moisture conditions resulted in a high association to subsurface values, indicating good correlation between the two zones. For example, initial results for this ongoing study from SM_13 show an overall low but increasing association from dry to intermediate soil moisture values (0 to 25%). At this range of values, we say that the two zones are decoupled. Above these values towards near saturated conditions ( 40%), associations between the two zones remain high. For predictor

  12. State of the science in cervical cancer: where we are today and where we need to go.

    Science.gov (United States)

    Dizon, Don S; Mackay, Helen J; Thomas, Gillian M; Werner, Theresa L; Kohn, Elise C; Hess, Dina; Rose, Peter G; Covens, Allan L

    2014-08-01

    Invasive cervical cancer remains an important global cause of death, despite the declining prevalence within the United States. Definitive therapies, including surgical resection of early-stage disease and chemoradiation for locally advanced disease, can be curative. For women who experience local or distant recurrences, the prognosis remains poor and better treatments are required. On July 18, 2013, The Gynecologic Oncology Group sponsored a State of the Science in Cervical Cancer Symposium with experts, researchers, clinicians, and interested stakeholders. This article summarize the progress that has been made, questions that require further investigation, and contemporary genomic findings and innovative treatments that may help inform the next generation of clinical trials for patients with cervical cancer. © 2014 American Cancer Society.

  13. A state of the science on influential factors related to sun protective behaviors to prevent skin cancer in adults

    Directory of Open Access Journals (Sweden)

    Amy F. Bruce, MSN, RN, NE-BC

    2017-07-01

    Full Text Available Skin cancer rates have risen over the past decades, making it imperative that adults understand the need for protection from sun exposure. Though some risk factors have been identified as predictive for skin cancers, there is a lack of synthesized information about factors that influence adults in their decisions to engage in sun protective behaviors. The purpose of this paper is to present the current state of the science on influential factors for sun protective behaviors in the general adult population. A rigorous literature search inclusive of a generally White, Caucasian, and non-Hispanic adult population was performed, and screening yielded 18 quantitative studies for inclusion in this review. Findings indicate that modifiable and non-modifiable factors are interdependent and play a role in sun protective behaviors. This study resulted in a proposed conceptual model for affecting behavioral change in sun protection including the following factors: personal characteristics, cognitive factors, family dynamics, and social/peer group influences. These factors are introduced to propose tailored nursing interventions that would change current sun protective behavior practice. Key implications for nursing research and practice focus on feasibility of annual skin cancer screening facilitated by advanced practice nurses, incorporating the identified influential factors to reduce skin cancer risk and unnecessary sun exposure.

  14. Microplastics as vectors for bioaccumulation of hydrophobic organic chemicals in the marine environment: A state-of-the-science review.

    Science.gov (United States)

    Ziccardi, Linda M; Edgington, Aaron; Hentz, Karyn; Kulacki, Konrad J; Kane Driscoll, Susan

    2016-07-01

    A state-of-the-science review was conducted to examine the potential for microplastics to sorb hydrophobic organic chemicals (HOCs) from the marine environment, for aquatic organisms to take up these HOCs from the microplastics, and for this exposure to result in adverse effects to ecological and human health. Despite concentrations of HOCs associated with microplastics that can be orders of magnitude greater than surrounding seawater, the relative importance of microplastics as a route of exposure is difficult to quantify because aquatic organisms are typically exposed to HOCs from various compartments, including water, sediment, and food. Results of laboratory experiments and modeling studies indicate that HOCs can partition from microplastics to organisms or from organisms to microplastics, depending on experimental conditions. Very little information is available to evaluate ecological or human health effects from this exposure. Most of the available studies measured biomarkers that are more indicative of exposure than effects, and no studies showed effects to ecologically relevant endpoints. Therefore, evidence is weak to support the occurrence of ecologically significant adverse effects on aquatic life as a result of exposure to HOCs sorbed to microplastics or to wildlife populations and humans from secondary exposure via the food chain. More data are needed to fully understand the relative importance of exposure to HOCs from microplastics compared with other exposure pathways. Environ Toxicol Chem 2016;35:1667-1676. © 2016 SETAC. © 2016 SETAC.

  15. Indication criteria for total hip or knee arthroplasty in osteoarthritis: a state-of-the-science overview.

    Science.gov (United States)

    Gademan, Maaike G J; Hofstede, Stefanie N; Vliet Vlieland, Thea P M; Nelissen, Rob G H H; Marang-van de Mheen, Perla J

    2016-11-09

    This systematic review gives an overview of guidelines and original publications as well as the evidence on which the currently proposed indication criteria are based. Until now such a state-of-the-science overview was lacking. Websites of orthopaedic and arthritis organizations (English/Dutch language) were independently searched by two authors for THA/TKA guidelines for OA. Furthermore, a systematic search strategy in several databases through August 2014 was performed. Quality of the guidelines was assessed with the AGREE II instrument, which consists of 6 domains (maximum summed score of 6 indicating high quality). Also, the level of evidence of all included studies was assessed. We found 6 guidelines and 18 papers, out of 3065 references. The quality of the guidelines summed across 6 domains ranged from 0.46 to 4.78. In total, 12 THA, 10 TKA and 2 THA/TKA indication sets were found. Four studies stated that no evidence-based indication criteria are available. Indication criteria concerning THA/TKA consisted of the following domains: pain (in respectively 11 and 10 sets), function (12 and 7 sets), radiological changes (10 and 9 sets), failed conservative therapy (8 and 4 sets) and other indications (6 and 7 sets). Specific cut-off values or ranges were often not stated and the level of evidence was low. The indication criteria for THA/TKA are based on limited evidence. Empirical research is needed, especially regarding domain specific cut-off values or ranges at which the best postoperative outcomes are achieved for patients, taking into account the limited lifespan of a prosthesis.

  16. 3D thermohydraulic modeling of the coupling of surface water bodies to the subsurface below the major urban center of Berlin

    Science.gov (United States)

    Frick, Maximilian; Scheck-Wenderoth, Magdalena; Cacace, Mauro; Schneider, Michael

    2017-04-01

    This study aims at a better understanding of the present-day thermal and hydraulic configuration below the major urban center of Berlin, capital city of Germany. The study area is located in the Northeast German Basin, showing an infill of several kilometers of sediments. Herein, the shallow sedimentary succession is made up of a sequence of alternating aquifers and aquitards, most importantly the local aquitard of the Rupelian clay. This geological unit represents a natural barrier between the deeper saline aquifers and the shallow fresh water aquifers from whom Berlin produces 100% of its drinking water. Additionally, the shallow thermal and hydraulic configuration has been anthropogenically overprinted which may also influence deeper domains to some extent. In this study we make use of 3D thermohydraulic models of the subsurface, focusing on the coupling of surface water bodies to the underground, based on newly available hydraulic data integrated into a 3D hydrogeological model. The results of the study show, that the coupling of surface water bodies and groundwater might lead to significant modifications of predicted subsurface temperatures and fluid flow field. These modifications are most prominent, where differences in hydraulic head between surface water bodies and the adjacent aquifers are highest. Consequently, the predicted surface to groundwater flow field differs most in these areas and it also results in differences in predicted temperatures as a consequence of advective heat transport. Quantitatively, the presence of major lakes may account for temperature differences up to 5°C, while considering rivers only accounts for modifications up to 1°C. Additionally, the models created in this study set up a basis for future thermohaline simulations as saline groundwater may represent a threat to drinking water supply. First results from the models run in this study already indicate, that uprising heated water from deeper domains may rise to shallow

  17. Alternative methods and strategies to reduce, refine, and replace animal use for veterinary vaccine post-licensing safety testing: state of the science and future directions

    OpenAIRE

    KULPA-EDDY Jodie; SRINIVAS Geetha; HALDER Maria; BROWN Karen; DRAAYER Hans; GALVIN Jeffrey; CLAASEN Ivo; WOODLAND Ralph; DOELLING Vivian; JONES Brett; STOKES William

    2011-01-01

    NICEATM and ICCVAM convened an international workshop to review the state of the science of human and veterinary vaccine potency and safety testing methods and to identify opportunities to advance new and improved methods that can further reduce, refine, and replace animal use. Six topics were addressed in detail by speakers and workshop participants and are reported in a series of six reports. This workshop report, the last in the series, addresses methods and strategies for veterinary vacci...

  18. Inverse Problem for 3D coupled Flow-Geomechanics Models and Induced Seismicity: Application to Subsurface Characterization and Seismicity Forecasting in Geologic CO2 Storage

    Science.gov (United States)

    Castineira, D.; Jha, B.; Juanes, R.

    2016-12-01

    Carbon Capture and Sequestration (CCS) is regarded as a promising technology to mitigate rising CO2 concentrations in the atmosphere from industrial emissions. However, as a result of the inherent uncertainty that is present in geological structures, assessing the stability of geological faults and quantifying the potential for induced seismicity is a fundamental challenge for practical implementation of CCS. Here we present a formal framework for the solution of the inverse problem associated with coupled flow and geomechanics models of CO2 injection and subsurface storage. Our approach builds from the application of Gaussian Processes, MCMC and posterior predictive analysis to evaluate relevant earthquake attributes (earthquake time, location and magnitude) in 3D synthetic models of CO2 storage under geologic, observational and operational uncertainty. In our approach, we first conduct hundreds of simulations of a high-fidelity 3D computational model for CO2 injection into a deep saline aquifer, dominated by an anticline structure and a fault. This ensemble of realizations accounts for uncertainty in the model parameters (including fault geomechanical and rock properties) and observations (earthquake time, location and magnitude). We apply Gaussian processes (GP) to generate a valid surrogate that closely approximates the behavior of the high fidelity (and computationally intensive) model, and apply hyperparameter optimization and cross-validation techniques in the solution of this multidimensional data-fit problem. The net result of this process is the generation of a fast model that can be effectively used for Bayesian analysis. We then implement Markov chain Monte Carlo (MCMC) to determine the posterior distribution of the model uncertain parameters (given some prior distributions for those parameters and given the likelihood defined in this case by the GP model). Our results show that the resulting posterior distributions correctly converge towards the "true

  19. Subsurface Transport Over Reactive Multiphases (STORM): A general, coupled, nonisothermal multiphase flow, reactive transport, and porous medium alteration simulator, Version 2 user's guide

    Energy Technology Data Exchange (ETDEWEB)

    DH Bacon; MD White; BP McGrail

    2000-03-07

    The Hanford Site, in southeastern Washington State, has been used extensively to produce nuclear materials for the US strategic defense arsenal by the Department of Energy (DOE) and its predecessors, the US Atomic Energy Commission and the US Energy Research and Development Administration. A large inventory of radioactive and mixed waste has accumulated in 177 buried single- and double shell tanks. Liquid waste recovered from the tanks will be pretreated to separate the low-activity fraction from the high-level and transuranic wastes. Vitrification is the leading option for immobilization of these wastes, expected to produce approximately 550,000 metric tons of Low Activity Waste (LAW) glass. This total tonnage, based on nominal Na{sub 2}O oxide loading of 20% by weight, is destined for disposal in a near-surface facility. Before disposal of the immobilized waste can proceed, the DOE must approve a performance assessment, a document that described the impacts, if any, of the disposal facility on public health and environmental resources. Studies have shown that release rates of radionuclides from the glass waste form by reaction with water determine the impacts of the disposal action more than any other independent parameter. This report describes the latest accomplishments in the development of a computational tool, Subsurface Transport Over Reactive Multiphases (STORM), Version 2, a general, coupled non-isothermal multiphase flow and reactive transport simulator. The underlying mathematics in STORM describe the rate of change of the solute concentrations of pore water in a variably saturated, non-isothermal porous medium, and the alteration of waste forms, packaging materials, backfill, and host rocks.

  20. State-of-the-science on prevention of elder abuse and lessons learned from child abuse and domestic violence prevention: Toward a conceptual framework for research

    Science.gov (United States)

    Teresi, Jeanne A.; Burnes, David; Skowron, Elizabeth A.; Dutton, Mary Ann; Mosqueda, Laura; Lachs, Mark S.; Pillemer, Karl

    2017-01-01

    The goal of this review is to discuss the state-of-the-science in elder abuse prevention. Findings from evidence-based programs to reduce elder abuse are discussed, drawing from findings and insights from evidence-based programs for child maltreatment and domestic/ intimate partner violence. A conceptual measurement model for the study of elder abuse is presented, and linked to possible measures of risk factors and outcomes. Advances in neuroscience in child maltreatment and novel measurement strategies for outcome assessment are presented. PMID:27676289

  1. State of the science on postacute rehabilitation: setting a research agenda and developing an evidence base for practice and public policy: an introduction

    Directory of Open Access Journals (Sweden)

    Heinemann Allen W

    2007-11-01

    Full Text Available Abstract The Rehabilitation Research and Training Center on Measuring Rehabilitation Outcomes and Effectiveness along with academic, professional, provider, accreditor and other organizations, sponsored a 2-day State-of-the-Science of Post-Acute Rehabilitation Symposium in February 2007. The aim of this symposium was to serve as a catalyst for expanded research on postacute care (PAC rehabilitation so that health policy is founded on a solid evidence base. The goals were to: (1 describe the state of our knowledge regarding utilization, organization and outcomes of postacute rehabilitation settings, (2 identify methodologic and measurement challenges to conducting research, (3 foster the exchange of ideas among researchers, policymakers, industry representatives, funding agency staff, consumers and advocacy groups, and (4 identify critical questions related to setting, delivery, payment and effectiveness of rehabilitation services. Plenary presentation and state-of-the-science summaries were organized around four themes: (1 the need for improved measurement of key rehabilitation variables and methods to collect and analyze this information, (2 factors that influence access to postacute rehabilitation care, (3 similarities and differences in quality and quantity of services across PAC settings, and (4 effectiveness of postacute rehabilitation services. The full set of symposium articles, including recommendations for future research, appear in Archives of Physical Medicine and Rehabilitation.

  2. Malignant Peripheral Nerve Sheath Tumors State of the Science: Leveraging Clinical and Biological Insights into Effective Therapies

    Directory of Open Access Journals (Sweden)

    AeRang Kim

    2017-01-01

    Full Text Available Malignant peripheral nerve sheath tumor (MPNST is the leading cause of mortality in patients with neurofibromatosis type 1. In 2002, an MPNST consensus statement reviewed the current knowledge and provided guidance for the diagnosis and management of MPNST. Although the improvement in clinical outcome has not changed, substantial progress has been made in understanding the natural history and biology of MPNST through imaging and genomic advances since 2002. Genetically engineered mouse models that develop MPNST spontaneously have greatly facilitated preclinical evaluation of novel drugs for translation into clinical trials led by consortia efforts. Continued work in identifying alterations that contribute to the transformation, progression, and metastasis of MPNST coupled with longitudinal follow-up, biobanking, and data sharing is needed to develop prognostic biomarkers and effective prevention and therapeutic strategies for MPNST.

  3. Subsurface connection methods for subsurface heaters

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Bass, Ronald Marshall (Houston, TX); Kim, Dong Sub (Sugar Land, TX); Mason, Stanley Leroy (Allen, TX); Stegemeier, George Leo (Houston, TX); Keltner, Thomas Joseph (Spring, TX); Carl, Jr., Frederick Gordon (Houston, TX)

    2010-12-28

    A system for heating a subsurface formation is described. The system includes a first elongated heater in a first opening in the formation. The first elongated heater includes an exposed metal section in a portion of the first opening. The portion is below a layer of the formation to be heated. The exposed metal section is exposed to the formation. A second elongated heater is in a second opening in the formation. The second opening connects to the first opening at or near the portion of the first opening below the layer to be heated. At least a portion of an exposed metal section of the second elongated heater is electrically coupled to at least a portion of the exposed metal section of the first elongated heater in the portion of the first opening below the layer to be heated.

  4. Short of breath and dying: state of the science on opioid agents for the palliation of refractory dyspnea in older adults.

    Science.gov (United States)

    Lowey, Susan E; Powers, Bethel Ann; Xue, Ying

    2013-02-01

    The purpose of this narrative literature review was to describe the state of the science on the effectiveness of opioid medications to palliate dyspnea in older adults with advanced disease. A three-stage critical appraisal process was used to evaluate articles published between 2000-2011 that were retrieved from the CINAHL, Ovid MEDLINE, and PsycINFO databases. Low-dose opioid medication use was associated with statistically significant reductions in dyspnea intensity scores in the majority of studies included in the analysis. Many recent articles on this topic shed light on the importance but underuse of opioid agents to palliate dyspnea, particularly in older adults with advanced chronic illnesses, such as heart failure and chronic obstructive pulmonary disease. ADRA (Assess, Document, Re-assess, Advocate) is a proposed framework that gerontological nurses can use to ensure patients receive adequate symptom management for refractory dyspnea. Copyright 2013, SLACK Incorporated.

  5. Techniques for thyroid FNA: a synopsis of the National Cancer Institute Thyroid Fine-Needle Aspiration State of the Science Conference.

    Science.gov (United States)

    Pitman, Martha Bishop; Abele, John; Ali, Syed Z; Duick, Dan; Elsheikh, Tarik M; Jeffrey, R Brooke; Powers, Celeste N; Randolph, Gregory; Renshaw, Andrew; Scoutt, Leslie

    2008-06-01

    The National Cancer Institute (NCI) sponsored the NCI Thyroid fine-needle aspiration (FNA) State of the Science Conference on October 22-23, 2007 in Bethesda, MD. The 2-day meeting was accompanied by a permanent informational website and several on-line discussion periods between May 1 and December 15, 2007 (http://thyroidfna.cancer.gov). This document summarizes matters addressing manual and ultrasound guided FNA technique and related issues. Specific topics covered include details regarding aspiration needles, devices, and methods, including the use of core needle biopsy; the pros and cons of anesthesia; the influence of thyroid lesion location, size, and characteristics on technique; the role of ultrasound in the FNA of a palpable thyroid nodule; the advantages and disadvantages of various specialists performing a biopsy; the optimal number of passes and tissue preparation methods; sample adequacy criteria for solid and cystic nodules, and management of adverse reactions from the procedure. (http://thyroidfna.cancer.gov/pages/info/agenda/)

  6. N{sub 2}O and CH{sub 4} Emission from Wastewater Collection and Treatment Systems (GWRC). State of the Science Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-15

    The Global Water Research Coalition (GWRC) is an international organisation that is dedicated to the exchange and generation of knowledge to support sustainable development and management of the urban water cycle. The research agenda is developed by the member organisations of the GWRC and reflects their priorities and recognises global trends and drivers that affect the urban water cycle. The present research agenda includes Climate Change as one of the priorities areas. This research area comprises topics related to the possible impact of climate change on the urban water sector as well as the possible contribution to climate change by the urban water sector via the direct and indirect emission of greenhouse gasses (GHG). The objective of this joint effort was to collect and develop knowledge needed to understand and manage the emission of N{sub 2}O (nitrous oxide) and CH{sub 4} (methane) by wastewater collection and treatment systems. Starting with a kick-off meeting in Vienna in September 2008, the GWRC members involved in this activity have bundled their individual research programs on this topic, aligned methodologies used and exchanged and discussed the resulting information of the programs and developed additional actions where needed. The outcomes were reviewed and discussed at a final workshop in Montreal in September 2010. These activities have resulted in two reports: this State of the Science report which presents an overview of the current knowledge and know-how regarding the emissions of N{sub 2}O and CH{sub 4} by wastewater collection and treatment systems and a Technical Report which includes all the details, facts and figures of the underlying studies used to develop the State of the Science report. For the Technical Report a separate record has been prepared.

  7. National Institutes of Health State-of-the-Science Conference Statement: Symptom management in cancer: pain, depression, and fatigue, July 15-17, 2002.

    Science.gov (United States)

    Patrick, Daniel L; Ferketich, Sandra L; Frame, Paul S; Harris, Jesse J; Hendricks, Carolyn B; Levin, Bernard; Link, Michael P; Lustig, Craig; McLaughlin, Joseph; Reid, L Douglas; Turrisi, Andrew T; Unützer, Jürgen; Vernon, Sally W

    2004-01-01

    Despite advances in early detection and effective treatment, cancer remains one of the most feared diseases. Among the most common side effects of cancer and treatments for cancer are pain, depression, and fatigue. Although research is producing increasingly hopeful insights into the causes and cures for cancer, efforts to manage the side effects of the disease and its treatments have not kept pace. The challenge that faces us is how to increase awareness of the importance of recognizing and actively addressing cancer-related distress. The National Institutes of Health (NIH) convened a State-of-the-Science Conference on Symptom Management in Cancer: Pain, Depression, and Fatigue to examine the current state of knowledge regarding the management of pain, depression, and fatigue in individuals with cancer and to identify directions for future research. Specifically, the conference examined how to identify individuals who are at risk for cancer-related pain, depression, and/or fatigue; what treatments work best to address these symptoms when they occur; and what is the best way to deliver interventions across the continuum of care. STATE-OF-THE-SCIENCE PROCESS: A non-advocate, non-Federal, 14-member panel of experts representing the fields of oncology, radiology, psychology, nursing, public health, social work, and epidemiology prepared the statement. In addition, 24 experts in medical oncology, geriatrics, pharmacology, psychology, and neurology presented data to the panel and to the conference audience during the first 1.5 days of the conference. The panel then prepared its statement, addressing the five predetermined questions and drawing on submitted literature, the speakers' presentations, and discussions held at the conference. The statement was presented to the conference audience, followed by a press conference to allow the panel to respond to questions from the media. After its release at the conference, the draft statement was made available on the Internet

  8. Saltcedar (Tamarix spp.) and Russian Olive (Elaeagnus angustifolia) in the Western United States-A Report on the State of the Science

    Science.gov (United States)

    Shafroth, Patrick

    2010-01-01

    The Salt Cedar and Russian Olive Control Demonstration Act of 2006 (Public Law 109-320) directs the Department of the Interior to submit a report to Congress that includes an assessment of several issues surrounding these two nonnative trees, now dominant components of the vegetation along many rivers in the Western United States. This report was published in 2010 as a U.S. Geological Survey Scientific Investigations Report (available online at http://pubs.usgs.gov/sir/2009/5247). The report was produced through a collaborative effort led by the Bureau of Reclamation and U.S. Geological Survey, with critical contributions from the U.S. Department of Agriculture and from university researchers. The document synthesizes the state of the science and key research needs on the following topics related to management of saltcedar (Tamarix spp.) and Russian olive (Elaeagnus angustifolia) in the Western United States: their distribution and abundance (extent); the potential for water savings associated with controlling these species; considerations related to wildlife use of saltcedar and Russian olive habitat and restored habitats; methods of control and removal; possible utilization of dead biomass following control and removal; and approaches and challenges associated with site revegetation or restoration. A concluding chapter discusses possible long-term management strategies, potentially useful field-demonstration projects, and a planning process for on-the-ground projects involving removal of saltcedar and Russian olive.

  9. Scoping review of adherence promotion theories in pelvic floor muscle training - 2011 ICS state-of-the-science seminar research paper i of iv.

    Science.gov (United States)

    McClurg, Doreen; Frawley, Helena; Hay-Smith, Jean; Dean, Sarah; Chen, Shu-Yueh; Chiarelli, Pauline; Mair, Frances; Dumoulin, Chantale

    2015-09-01

    This paper, the first of four emanating from the International Continence Society's 2011 State-of-the-Science Seminar on pelvic-floor-muscle training (PFMT) adherence, aimed to summarize the literature on theoretical models to promote PFMT adherence, as identified in the research, or suggested by the seminar's expert panel, and recommends future directions for clinical practice and research. Existing literature on theories of health behavior were identified through a conventional subject search of electronic databases, reference-list checking, and input from the expert panel. A core eligibility criterion was that the study included a theoretical model to underpin adherence strategies used in an intervention to promote PFM training/exercise. A brief critique of 12 theoretical models/theories is provided and, were appropriate, their use in PFMT adherence strategies identified or examples of possible uses in future studies outlined. A better theoretical-based understanding of interventions to promote PFMT adherence through changes in health behaviors is required. The results of this scoping review and expert opinions identified several promising models. Future research should explicitly map the theories behind interventions that are thought to improve adherence in various populations (e.g., perinatal women to prevent or lessen urinary incontinence). In addition, identified behavioral theories applied to PFMT require a process whereby their impact can be evaluated. © 2015 Wiley Periodicals, Inc.

  10. The information needs of North American parents of children with asthma: a state-of-the-science review of the literature.

    Science.gov (United States)

    Archibald, Mandy M; Scott, Shannon D

    2014-01-01

    Asthma, the most common chronic disease of childhood, presents diverse challenges to parents who are responsible for its management. Parents must be informed regarding symptom recognition, medications, prevention, and treatment to effectively minimize acute exacerbations and asthma sequela. Current approaches to asthma education do not address the vast range of information needs of parents, and few studies explicitly identify parental information needs in a comprehensive manner. To address this gap and to create a parental information needs taxonomy, a "state-of-the-science" review of the literature was conducted. Three electronic databases were searched and articles were screened according to pre-established inclusion criteria. Of 164 articles retrieved, 11 articles met the inclusion criteria and were included in the review. Parental information needs can be classified in the following categories: asthma basics, treatment modalities, coping, and medical expectations. This information needs taxonomy may help practitioners better address the information needs of parents of children with asthma. Copyright © 2014 National Association of Pediatric Nurse Practitioners. Published by Mosby, Inc. All rights reserved.

  11. Coupled land surface–subsurface hydrogeophysical inverse modeling to estimate soil organic carbon content and explore associated hydrological and thermal dynamics in the Arctic tundra

    Directory of Open Access Journals (Sweden)

    A. P. Tran

    2017-09-01

    Full Text Available Quantitative characterization of soil organic carbon (OC content is essential due to its significant impacts on surface–subsurface hydrological–thermal processes and microbial decomposition of OC, which both in turn are important for predicting carbon–climate feedbacks. While such quantification is particularly important in the vulnerable organic-rich Arctic region, it is challenging to achieve due to the general limitations of conventional core sampling and analysis methods, and to the extremely dynamic nature of hydrological–thermal processes associated with annual freeze–thaw events. In this study, we develop and test an inversion scheme that can flexibly use single or multiple datasets – including soil liquid water content, temperature and electrical resistivity tomography (ERT data – to estimate the vertical distribution of OC content. Our approach relies on the fact that OC content strongly influences soil hydrological–thermal parameters and, therefore, indirectly controls the spatiotemporal dynamics of soil liquid water content, temperature and their correlated electrical resistivity. We employ the Community Land Model to simulate nonisothermal surface–subsurface hydrological dynamics from the bedrock to the top of canopy, with consideration of land surface processes (e.g., solar radiation balance, evapotranspiration, snow accumulation and melting and ice–liquid water phase transitions. For inversion, we combine a deterministic and an adaptive Markov chain Monte Carlo (MCMC optimization algorithm to estimate a posteriori distributions of desired model parameters. For hydrological–thermal-to-geophysical variable transformation, the simulated subsurface temperature, liquid water content and ice content are explicitly linked to soil electrical resistivity via petrophysical and geophysical models. We validate the developed scheme using different numerical experiments and evaluate the influence of measurement errors and

  12. Coupled land surface-subsurface hydrogeophysical inverse modeling to estimate soil organic carbon content and explore associated hydrological and thermal dynamics in the Arctic tundra

    Science.gov (United States)

    Phuong Tran, Anh; Dafflon, Baptiste; Hubbard, Susan S.

    2017-09-01

    Quantitative characterization of soil organic carbon (OC) content is essential due to its significant impacts on surface-subsurface hydrological-thermal processes and microbial decomposition of OC, which both in turn are important for predicting carbon-climate feedbacks. While such quantification is particularly important in the vulnerable organic-rich Arctic region, it is challenging to achieve due to the general limitations of conventional core sampling and analysis methods, and to the extremely dynamic nature of hydrological-thermal processes associated with annual freeze-thaw events. In this study, we develop and test an inversion scheme that can flexibly use single or multiple datasets - including soil liquid water content, temperature and electrical resistivity tomography (ERT) data - to estimate the vertical distribution of OC content. Our approach relies on the fact that OC content strongly influences soil hydrological-thermal parameters and, therefore, indirectly controls the spatiotemporal dynamics of soil liquid water content, temperature and their correlated electrical resistivity. We employ the Community Land Model to simulate nonisothermal surface-subsurface hydrological dynamics from the bedrock to the top of canopy, with consideration of land surface processes (e.g., solar radiation balance, evapotranspiration, snow accumulation and melting) and ice-liquid water phase transitions. For inversion, we combine a deterministic and an adaptive Markov chain Monte Carlo (MCMC) optimization algorithm to estimate a posteriori distributions of desired model parameters. For hydrological-thermal-to-geophysical variable transformation, the simulated subsurface temperature, liquid water content and ice content are explicitly linked to soil electrical resistivity via petrophysical and geophysical models. We validate the developed scheme using different numerical experiments and evaluate the influence of measurement errors and benefit of joint inversion on the

  13. Pelvic-Floor-Muscle Training Adherence: Tools, Measurements and Strategies-2011 ICS State-of-the-Science Seminar Research Paper II of IV.

    Science.gov (United States)

    Dumoulin, Chantal; Alewijnse, Dianne; Bo, Kari; Hagen, Suzanne; Stark, Diane; Van Kampen, Marijke; Herbert, Julia; Hay-Smith, Jean; Frawley, Helena; McClurg, Doreen; Dean, Sarah

    2015-09-01

    This paper on pelvic-floor-muscle training (PFMT) adherence, the second of four from the International Continence Society's 2011 State-of-the-Science Conference, aims to (1) identify and collate current adherence outcome measures, (2) report the determinants of adherence, (3) report on PFMT adherence strategies, and (4) make actionable clinical and research recommendations. Data were amassed from a literature review and an expert panel (2011 conference), following consensus statement methodology. Experts in pelvic floor dysfunction collated and synthesized the evidence and expert opinions on PFMT adherence for urinary incontinence (UI) and lower bowel dysfunction in men and women and pelvic organ prolapse in women. The literature was scarce for most of the studied populations except for limited research on women with UI. Exercise diaries were the most widely-used adherence outcome measure, PFMT adherence was inconsistently monitored and inadequately reported. Determinants: Research, mostly secondary analyses of RCTs, suggested that intention to adhere, self-efficacy expectations, attitudes towards the exercises, perceived benefits and a high social pressure to engage in PFMT impacted adherence. Few trials studied and compared adherence strategies. A structured PFMT programme, an enthusiastic physiotherapist, audio prompts, use of established theories of behavior change, and user-consultations seem to increase adherence. The literature on adherence outcome measures, determinants and strategies remains scarce for the studied populations with PFM dysfunction, except in women with UI. Although some current adherence findings can be applied to clinical practice, more effective and standardized research is urgently needed across all the sub-populations. © 2015 Wiley Periodicals, Inc.

  14. State-of-the-science review of the occupational health hazards of crystalline silica in abrasive blasting operations and related requirements for respiratory protection.

    Science.gov (United States)

    Madl, Amy K; Donovan, Ellen P; Gaffney, Shannon H; McKinley, Meg A; Moody, Emily C; Henshaw, John L; Paustenbach, Dennis J

    2008-08-01

    Excessive exposures to airborne crystalline silica have been known for over 100 years to pose a serious health hazard. Work practices and regulatory standards advanced as the knowledge of the hazards of crystalline silica evolved. This article presents a comprehensive historical examination of the literature on exposure, health effects, and personal protective equipment related to silica and abrasive blasting operations over the last century. In the early 1900s, increased death rates and prevalence of pulmonary disease were observed in industries that involved dusty operations. Studies of these occupational cohorts served as the basis for the first occupational exposure limits in the 1930s. Early exposure studies in foundries revealed that abrasive blasting operations were particularly hazardous and provided the basis for many of the engineering control and respiratory protection requirements that are still in place today. Studies involving abrasive blasters over the years revealed that engineering controls were often not completely effective at reducing airborne silica concentrations to a safe level; consequently, respiratory protection has always been an important component of protecting workers. During the last 15-20 yr, quantitative exposure-response modeling, experimental animal studies, and in vitro methods were used to better understand the relationship between exposure to silica and disease in the workplace. In light of Occupational Safety and Health Administration efforts to reexamine the protectiveness of the current permissible exposure limit (PEL) for crystalline silica and its focus on protecting workers who are known to still be exposed to silica in the workplace (including abrasive blasters), this state-of-the-science review of one of the most hazardous operations involving crystalline silica should provide useful background to employers, researchers, and regulators interested in the historical evolution of the recognized occupational health hazards

  15. Subsurface Uranium Fate and Transport: Integrated Experiments and Modeling of Coupled Biogeochemical Mechanisms of Nanocrystalline Uraninite Oxidation by Fe(III)-(hydr)oxides - Project Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Peyton, Brent M. [Montana State Univ., Bozeman, MT (United States); Timothy, Ginn R. [Univ. of California, Davis, CA (United States); Sani, Rajesh K. [South Dakota School of Mines and Technology, Rapid City, SD (United States)

    2013-08-14

    Subsurface bacteria including sulfate reducing bacteria (SRB) reduce soluble U(VI) to insoluble U(IV) with subsequent precipitation of UO2. We have shown that SRB reduce U(VI) to nanometer-sized UO2 particles (1-5 nm) which are both intra- and extracellular, with UO2 inside the cell likely physically shielded from subsequent oxidation processes. We evaluated the UO2 nanoparticles produced by Desulfovibrio desulfuricans G20 under growth and non-growth conditions in the presence of lactate or pyruvate and sulfate, thiosulfate, or fumarate, using ultrafiltration and HR-TEM. Results showed that a significant mass fraction of bioreduced U (35-60%) existed as a mobile phase when the initial concentration of U(VI) was 160 µM. Further experiments with different initial U(VI) concentrations (25 - 900 M) in MTM with PIPES or bicarbonate buffers indicated that aggregation of uraninite depended on the initial concentrations of U(VI) and type of buffer. It is known that under some conditions SRB-mediated UO2 nanocrystals can be reoxidized (and thus remobilized) by Fe(III)-(hydr)oxides, common constituents of soils and sediments. To elucidate the mechanism of UO2 reoxidation by Fe(III) (hydr)oxides, we studied the impact of Fe and U chelating compounds (citrate, NTA, and EDTA) on reoxidation rates. Experiments were conducted in anaerobic batch systems in PIPES buffer. Results showed EDTA significantly accelerated UO2 reoxidation with an initial rate of 9.5 M day-1 for ferrihydrite. In all cases, bicarbonate increased the rate and extent of UO2 reoxidation with ferrihydrite. The highest rate of UO2 reoxidation occurred when the chelator promoted UO2 and Fe(III) (hydr)oxide dissolution as demonstrated with EDTA. When UO2 dissolution did not occur, UO2 reoxidation likely proceeded through an aqueous Fe(III) intermediate as observed for both NTA and

  16. Assimilation of subsurface thermal data into a simple ocean model for the initialization of an intermediate tropical coupled ocean-atmosphere forecast model

    Energy Technology Data Exchange (ETDEWEB)

    Kleeman, R.; Moore, A.M.; Smith, N.R. [Bureau of Meteorology Research Centre, Melbourne, Victoria (Australia)

    1995-10-01

    An adjoint variational assimilation technique is used to assimilate observations of both the oceanic state and wind stress data into an intermediate coupled ENSO prediction model. This method of initialization is contrasted with the more usual method, which uses only wind stress data to establish the initial state of the ocean. It is shown that ocean temperature data has a positive impact on the prediction skill in such models. On the basis of hindcasts for the period 1982-91, it is shown that NINO3 SST anomaly correlations greater than 0.7 can be obtained for hindcasts of duration up to 13 months and greater than 0.6 up to 16 months. There are also clear indications of skill at two years. 24 refs., 8 figs., 1 tab.

  17. Subsurface Microbiology and Biogeochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Fredrickson, Jim K.; Fletcher, Madilyn

    2001-05-01

    Jim contributed a chapter to this book, in addition to co-editing it with Madilyn Fletcher. Fredrickson, J. K., and M. Fletcher. (eds.) 2001 Subsurface Microbiology and Biogeochemistry. Wiley-Liss, Inc., New York.

  18. Electrical Subsurface Grounding Analysis

    Energy Technology Data Exchange (ETDEWEB)

    J.M. Calle

    2000-11-01

    The purpose and objective of this analysis is to determine the present grounding requirements of the Exploratory Studies Facility (ESF) subsurface electrical system and to verify that the actual grounding system and devices satisfy the requirements.

  19. Subsurface Intrusion Detection System

    Science.gov (United States)

    2014-02-25

    fre­ quency seismic vibrations and can therefore detect even rela­ tively small vibrations associated with tunneling or other subsurface activity...may indicate a surreptitious attempt to cross the boundary protected by system 100. Activity in digging or moving within tunnel 160 creates seismic ...magnitude of seismic vibrations associated with subsurface activity indicative of unauthorized attempts to tunnel across the boundary protected by

  20. Subsurface Contamination Control

    Energy Technology Data Exchange (ETDEWEB)

    Y. Yuan

    2001-12-12

    There are two objectives of this report, ''Subsurface Contamination Control''. The first is to provide a technical basis for recommending limiting radioactive contamination levels (LRCL) on the external surfaces of waste packages (WP) for acceptance into the subsurface repository. The second is to provide an evaluation of the magnitude of potential releases from a defective WP and the detectability of the released contents. The technical basis for deriving LRCL has been established in ''Retrieval Equipment and Strategy for Wp on Pallet'' (CRWMS M and O 2000g, 6.3.1). This report updates the derivation by incorporating the latest design information of the subsurface repository for site recommendation. The derived LRCL on the external surface of WPs, therefore, supercede that described in CRWMS M and O 2000g. The derived LRCL represent the average concentrations of contamination on the external surfaces of each WP that must not be exceeded before the WP is to be transported to the subsurface facility for emplacement. The evaluation of potential releases is necessary to control the potential contamination of the subsurface repository and to detect prematurely failed WPs. The detection of failed WPs is required in order to provide reasonable assurance that the integrity of each WP is intact prior to MGR closure. An emplaced WP may become breached due to manufacturing defects or improper weld combined with failure to detect the defect, by corrosion, or by mechanical penetration due to accidents or rockfall conditions. The breached WP may release its gaseous and volatile radionuclide content to the subsurface environment and result in contaminating the subsurface facility. The scope of this analysis is limited to radioactive contaminants resulting from breached WPs during the preclosure period of the subsurface repository. This report: (1) documents a method for deriving LRCL on the external surfaces of WP for acceptance into the

  1. Continuum-based models and concepts for the transport of nanoparticles in saturated porous media: A state-of-the-science review.

    Science.gov (United States)

    Babakhani, Peyman; Bridge, Jonathan; Doong, Ruey-An; Phenrat, Tanapon

    2017-08-01

    Environmental applications of nanoparticles (NP) increasingly result in widespread NP distribution within porous media where they are subject to various concurrent transport mechanisms including irreversible deposition, attachment/detachment (equilibrium or kinetic), agglomeration, physical straining, site-blocking, ripening, and size exclusion. Fundamental research in NP transport is typically conducted at small scale, and theoretical mechanistic modeling of particle transport in porous media faces challenges when considering the simultaneous effects of transport mechanisms. Continuum modeling approaches, in contrast, are scalable across various scales ranging from column experiments to aquifer. They have also been able to successfully describe the simultaneous occurrence of various transport mechanisms of NP in porous media such as blocking/straining or agglomeration/deposition/detachment. However, the diversity of model equations developed by different authors and the lack of effective approaches for their validation present obstacles to the successful robust application of these models for describing or predicting NP transport phenomena. This review aims to describe consistently all the important NP transport mechanisms along with their representative mathematical continuum models as found in the current scientific literature. Detailed characterizations of each transport phenomenon in regards to their manifestation in the column experiment outcomes, i.e., breakthrough curve (BTC) and residual concentration profile (RCP), are presented to facilitate future interpretations of BTCs and RCPs. The review highlights two NP transport mechanisms, agglomeration and size exclusion, which are potentially of great importance in controlling the fate and transport of NP in the subsurface media yet have been widely neglected in many existing modeling studies. A critical limitation of the continuum modeling approach is the number of parameters used upon application to larger

  2. Terrestrial Subsurface Ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Wilkins, Michael J.; Fredrickson, Jim K.

    2015-10-15

    The Earth’s crust is a solid cool layer that overlays the mantle, with a varying thickness of between 30-50 km on continental plates, and 5-10 km on oceanic plates. Continental crust is composed of a variety of igneous, metamorphic, and sedimentary rocks that weather and re-form over geologic cycles lasting millions to billions of years. At the crust surface, these weathered minerals and organic material combine to produce a variety of soils types that provide suitable habitats and niches for abundant microbial diversity (see Chapter 4). Beneath this soil zone is the subsurface. Once thought to be relatively free of microorganisms, recent estimates have calculated that between 1016-1017 g C biomass (2-19% of Earth’s total biomass) may be present in this environment (Whitman et al., 1998;McMahon and Parnell, 2014). Microbial life in the subsurface exists across a wide range of habitats: in pores associated with relatively shallow unconsolidated aquifer sediments to fractures in bedrock formations that are more than a kilometer deep, where extreme lithostatic pressures and temperatures are encountered. While these different environments contain varying physical and chemical conditions, the absence of light is a constant. Despite this, diverse physiologies and metabolisms enable microorganisms to harness energy and carbon for growth in water-filled pore spaces and fractures. Carbon and other element cycles are driven by microbial activity, which has implications for both natural processes and human activities in the subsurface, e.g., bacteria play key roles in both hydrocarbon formation and degradation. Hydrocarbons are a major focus for human utilization of the subsurface, via oil and gas extraction and potential geologic CO2 sequestration. The subsurface is also utilized or being considered for sequestered storage of high-level radioactive waste from nuclear power generation and residual waste from past production of weapons grade nuclear materials. While our

  3. SUBSURFACE EMPLACEMENT TRANSPORTATION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    T. Wilson; R. Novotny

    1999-11-22

    The objective of this analysis is to identify issues and criteria that apply to the design of the Subsurface Emplacement Transportation System (SET). The SET consists of the track used by the waste package handling equipment, the conductors and related equipment used to supply electrical power to that equipment, and the instrumentation and controls used to monitor and operate those track and power supply systems. Major considerations of this analysis include: (1) Operational life of the SET; (2) Geometric constraints on the track layout; (3) Operating loads on the track; (4) Environmentally induced loads on the track; (5) Power supply (electrification) requirements; and (6) Instrumentation and control requirements. This analysis will provide the basis for development of the system description document (SDD) for the SET. This analysis also defines the interfaces that need to be considered in the design of the SET. These interfaces include, but are not limited to, the following: (1) Waste handling building; (2) Monitored Geologic Repository (MGR) surface site layout; (3) Waste Emplacement System (WES); (4) Waste Retrieval System (WRS); (5) Ground Control System (GCS); (6) Ex-Container System (XCS); (7) Subsurface Electrical Distribution System (SED); (8) MGR Operations Monitoring and Control System (OMC); (9) Subsurface Facility System (SFS); (10) Subsurface Fire Protection System (SFR); (11) Performance Confirmation Emplacement Drift Monitoring System (PCM); and (12) Backfill Emplacement System (BES).

  4. Subsurface contaminants focus area

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  5. Workplace incivility: state of the science.

    Science.gov (United States)

    Hutton, Scott A

    2006-01-01

    The financial cost of workplace violence is 4.2 billion dollars a year. Workplace incivility may initiate a spiral that for 1,000 people a year ends in death at work. If an initial minor incident such as incivility could be mitigated, then the financial and human capital that could be realized by the healthcare organization is immense. This article is an in-depth look at the literature and theoretical frameworks related to workplace incivility.

  6. Urban Air Pollution: State of the Science.

    Science.gov (United States)

    Seinfeld, John H.

    1989-01-01

    Describes the highly complex mixture of gaseous and particulate matter found in urban air. Explains progress made in the understanding of the physics and chemistry of air pollution, the effects of precursors on ozone, the role of biogenic hydrocarbons, and the principal benefit of methanol-fueled vehicles. (RT)

  7. Cancer fatalism: the state of the science.

    Science.gov (United States)

    Powe, Barbara D; Finnie, Ramona

    2003-12-01

    Cancer fatalism--the belief that death is inevitable when cancer is present--has been identified as a barrier to participation in cancer screening, detection, and treatment. Yet this literature has not been reviewed in a comprehensive and systematic manner. Therefore, this literature review addressed (1) philosophical and theoretical underpinnings of cancer fatalism; (2) relationships among demographic factors, cancer fatalism, and cancer screening; (3) the role of cancer fatalism for patients diagnosed with cancer; and (4) intervention strategies. Most of the reviewed studies were descriptive or correlational, did not have an explicit theoretical framework, had varied definitions of fatalism, and reported screening as "intent to screen" or as "past screening behaviors." Review of the studies suggests that cancer fatalism develops over time and is most frequently reported among medically underserved persons and those with limited knowledge of cancer. Cancer fatalism may be modified through culturally relevant interventions that incorporate spirituality. Emphasis must be placed on recognizing the role of cancer fatalism when planning health promotion activities. Future studies should focus on the consistent measurement of cancer fatalism and testing intervention strategies.

  8. State of the Science-Ultraendurance Sports.

    Science.gov (United States)

    Hoffman, Martin D

    2016-09-01

    Participation in ultraendurance sports has been increasing in recent years. This participation growth has been associated with an increase in research focused on such events. While the total amount of research related to these sports remains relatively small compared with other sports, the research growth is encouraging. New sources for research funding for ultraendurance sports should advance the science. In addition to continued opportunities with observational studies, promising areas of investigation remain for experimental studies and research that uses ultraendurance-sport environments as models for studies relevant to wider populations. Insight into the breadth of research opportunities in ultraendurance sports can be gained by reviewing the abstracts published online in the International Journal of Sports Physiology and Performance from the annual Medicine & Science in Ultra-Endurance Sports Conference that took place this year in Chamonix, France.

  9. Aviation Noise Impacts: State of the Science

    NARCIS (Netherlands)

    Basner, M.; Clark, C.; Hansell, A.; Hileman, J.; Janssen, S.; Shepherd, K.; Sparrow, V.

    2017-01-01

    Noise is defined as 'unwanted sound.' Aircraft noise is one, if not the most detrimental environmental effect of aviation. It can cause community annoyance, disrupt sleep, adversely affect academic performance of children, and could increase the risk for cardiovascular disease of people living in

  10. Microbial source tracking: state of the science.

    Science.gov (United States)

    Simpson, Joyce M; Santo Domingo, Jorge W; Reasoner, Donald J

    2002-12-15

    Although water quality of the Nation's lakes, rivers and streams has been monitored for many decades and especially since the passage of the Clean Water Act in 1972, many still do not meet the Act's goal of "fishable and swimmable". While waterways can be impaired in numerous ways, the protection from pathogenic microbe contamination is most important for waters used for human recreation, drinking water and aquaculture. Typically, monitoring methods used for detecting potential pathogenic microorganisms in environmental waters are based upon cultivation and enumeration of fecal indicator bacteria (i.e. fecal coliforms, E. coli, and fecal enterococci). Currently, there is increasing interest in the potential for molecular fingerprinting methods to be used not only for detection but also for identification of fecal contamination sources. Molecular methods have been applied to study the microbial ecology of environmental systems for years and are now being applied to help improve our waters by identifying problem sources and determining the effect of implemented remedial solutions. Management and remediation of water pollution would be more cost-effective if the correct sources could be identified. This review provides an outline of the main methods that either have been used or have been suggested for use in microbial source tracking and some of the limitations associated with those methods.

  11. Change in ocean subsurface environment to suppress tropical cyclone intensification under global warming

    Science.gov (United States)

    Huang, Ping; Lin, I. -I; Chou, Chia; Huang, Rong-Hui

    2015-01-01

    Tropical cyclones (TCs) are hazardous natural disasters. Because TC intensification is significantly controlled by atmosphere and ocean environments, changes in these environments may cause changes in TC intensity. Changes in surface and subsurface ocean conditions can both influence a TC's intensification. Regarding global warming, minimal exploration of the subsurface ocean has been undertaken. Here we investigate future subsurface ocean environment changes projected by 22 state-of-the-art climate models and suggest a suppressive effect of subsurface oceans on the intensification of future TCs. Under global warming, the subsurface vertical temperature profile can be sharpened in important TC regions, which may contribute to a stronger ocean coupling (cooling) effect during the intensification of future TCs. Regarding a TC, future subsurface ocean environments may be more suppressive than the existing subsurface ocean environments. This suppressive effect is not spatially uniform and may be weak in certain local areas. PMID:25982028

  12. Subsurface Biogeochemistry of Actinides

    Energy Technology Data Exchange (ETDEWEB)

    Kersting, Annie B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Univ. Relations and Science Education; Zavarin, Mavrik [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Glenn T. Seaborg Inst.

    2016-06-29

    A major scientific challenge in environmental sciences is to identify the dominant processes controlling actinide transport in the environment. It is estimated that currently, over 2200 metric tons of plutonium (Pu) have been deposited in the subsurface worldwide, a number that increases yearly with additional spent nuclear fuel (Ewing et al., 2010). Plutonium has been shown to migrate on the scale of kilometers, giving way to a critical concern that the fundamental biogeochemical processes that control its behavior in the subsurface are not well understood (Kersting et al., 1999; Novikov et al., 2006; Santschi et al., 2002). Neptunium (Np) is less prevalent in the environment; however, it is predicted to be a significant long-term dose contributor in high-level nuclear waste. Our focus on Np chemistry in this Science Plan is intended to help formulate a better understanding of Pu redox transformations in the environment and clarify the differences between the two long-lived actinides. The research approach of our Science Plan combines (1) Fundamental Mechanistic Studies that identify and quantify biogeochemical processes that control actinide behavior in solution and on solids, (2) Field Integration Studies that investigate the transport characteristics of Pu and test our conceptual understanding of actinide transport, and (3) Actinide Research Capabilities that allow us to achieve the objectives of this Scientific Focus Area (SFA and provide new opportunities for advancing actinide environmental chemistry. These three Research Thrusts form the basis of our SFA Science Program (Figure 1).

  13. Final report for grant number DE-FG02-06ER64244 to the University of Idaho (RW Smith)-coupling between flow and precipitation in heterogeneous subsurface environments and effects on contaminant fate and transport

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Robert W. [Univ. of Idaho, Idaho Falls, ID (United States); Beig, Mikala S. [Univ. of Idaho, Idaho Falls, ID (United States); Gebrehiwet, Tsigabu [Univ. of Idaho, Idaho Falls, ID (United States); Corriveau, Catherine E. [Univ. of Idaho, Idaho Falls, ID (United States); Redden, George [Idaho National Lab. (INL), Idaho Falls, ID (United States); Fujita, Yoshiko [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2010-06-18

    Engineered remediation strategies for inducing mineral precipitation in the subsurface typically involve the introduction of at least one reactant either by direct injection or by in situ generation. The localization of reactant sources means a wide range of saturation states and ion ratios will be created as reactants are mixed: These conditions together can result in a wide range of precipitation rates, as well as impact which mineral phase precipitates. This is potentially important for the capacity of the precipitates to take up of trace metal contaminants, for their long term stability. Aragonite, for example, is able to sequester a larger amount of Sr than calcite. However, aragonite is less stable under typical groundwater conditions, and so may release sequestered Sr over time as the aragonite transforms to a more stable phase. In addition, previous experimental studies have indicated that other system constituents may influence calcium carbonate precipitation and consequently the Sr uptake potential of a system. For example, dissolved organic carbon (at levels typical of groundwaters) can suppress crystal growth. As a result, the continuous nucleation of small crystals, rather than growth of existing crystals, may be the dominant mode of precipitation. This has the potential for greater uptake of Sr because the smaller crystal sizes associated with nucleated calcite may more readily accommodate the distortion resulting from substitution of the larger Sr ion for Ca ions than can larger crystals. However, these smaller crystals may also be less stable and over the long term release Sr as a result of Ostwald ripening. To better understand the formation and composition of relevant calcium carbonate mineral phases two related series of mineral precipitation experiments were conducted. The first series of experiments, conducted using a Continuously Stirred Tank Reactor (CSTR) operated at steady state rates of precipitation was focused on understanding the

  14. BLT-EC (Breach, Leach and Transport-Equilibrium Chemistry) data input guide. A computer model for simulating release and coupled geochemical transport of contaminants from a subsurface disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    MacKinnon, R.J. [Brookhaven National Lab., Upton, NY (United States)]|[Ecodynamic Research Associates, Inc., Albuquerque, NM (United States); Sullivan, T.M.; Kinsey, R.R. [Brookhaven National Lab., Upton, NY (United States)

    1997-05-01

    The BLT-EC computer code has been developed, implemented, and tested. BLT-EC is a two-dimensional finite element computer code capable of simulating the time-dependent release and reactive transport of aqueous phase species in a subsurface soil system. BLT-EC contains models to simulate the processes (container degradation, waste-form performance, transport, chemical reactions, and radioactive production and decay) most relevant to estimating the release and transport of contaminants from a subsurface disposal system. Water flow is provided through tabular input or auxiliary files. Container degradation considers localized failure due to pitting corrosion and general failure due to uniform surface degradation processes. Waste-form performance considers release to be limited by one of four mechanisms: rinse with partitioning, diffusion, uniform surface degradation, and solubility. Transport considers the processes of advection, dispersion, diffusion, chemical reaction, radioactive production and decay, and sources (waste form releases). Chemical reactions accounted for include complexation, sorption, dissolution-precipitation, oxidation-reduction, and ion exchange. Radioactive production and decay in the waste form is simulated. To improve the usefulness of BLT-EC, a pre-processor, ECIN, which assists in the creation of chemistry input files, and a post-processor, BLTPLOT, which provides a visual display of the data have been developed. BLT-EC also includes an extensive database of thermodynamic data that is also accessible to ECIN. This document reviews the models implemented in BLT-EC and serves as a guide to creating input files and applying BLT-EC.

  15. Subsurface Facility System Description Document

    Energy Technology Data Exchange (ETDEWEB)

    Eric Loros

    2001-07-31

    The Subsurface Facility System encompasses the location, arrangement, size, and spacing of the underground openings. This subsurface system includes accesses, alcoves, and drifts. This system provides access to the underground, provides for the emplacement of waste packages, provides openings to allow safe and secure work conditions, and interfaces with the natural barrier. This system includes what is now the Exploratory Studies Facility. The Subsurface Facility System physical location and general arrangement help support the long-term waste isolation objectives of the repository. The Subsurface Facility System locates the repository openings away from main traces of major faults, away from exposure to erosion, above the probable maximum flood elevation, and above the water table. The general arrangement, size, and spacing of the emplacement drifts support disposal of the entire inventory of waste packages based on the emplacement strategy. The Subsurface Facility System provides access ramps to safely facilitate development and emplacement operations. The Subsurface Facility System supports the development and emplacement operations by providing subsurface space for such systems as ventilation, utilities, safety, monitoring, and transportation.

  16. Predictability of Subsurface Temperature and the AMOC

    Science.gov (United States)

    Chang, Y.; Schubert, S. D.

    2013-12-01

    GEOS 5 coupled model is extensively used for experimental decadal climate prediction. Understanding the limits of decadal ocean predictability is critical for making progress in these efforts. Using this model, we study the subsurface temperature initial value predictability, the variability of the Atlantic meridional overturning circulation (AMOC) and its impacts on the global climate. Our approach is to utilize the idealized data assimilation technology developed at the GMAO. The technique 'replay' allows us to assess, for example, the impact of the surface wind stresses and/or precipitation on the ocean in a very well controlled environment. By running the coupled model in replay mode we can in fact constrain the model using any existing reanalysis data set. We replay the model constraining (nudging) it to the MERRA reanalysis in various fields from 1948-2012. The fields, u,v,T,q,ps, are adjusted towards the 6-hourly analyzed fields in atmosphere. The simulated AMOC variability is studied with a 400-year-long segment of replay integration. The 84 cases of 10-year hindcasts are initialized from 4 different replay cycles. Here, the variability and predictability are examined further by a measure to quantify how much the subsurface temperature and AMOC variability has been influenced by atmospheric forcing and by ocean internal variability. The simulated impact of the AMOC on the multi-decadal variability of the SST, sea surface height (SSH) and sea ice extent is also studied.

  17. Effect of Periodic Surface Air Temperature Variations on Subsurface Thermal Structure with Vertical Fluid flow

    Science.gov (United States)

    D, R. V.; Ravi, M.; Srivastava, K.

    2016-12-01

    The influence of climate change on near subsurface temperatures is an important research topic for global change impact assessment at the regional scale. The varying temperature of the air over the surface in long term will disturb subsurface thermal structure. Groundwater flow is another important process which perturbs the thermal distribution into the subsurface. To investigate the effect of periodic air temperature on nonisothermal subsurface, one dimensional transient heat conduction-advection equation is solved numerically using finite element method. Thermal response of subsurface for periodic variations in surface air temperature (SAT) with robin type boundary condition on the surface with vertical ground water flow are calculated and the amplitude attenuation of propagation of surface temperature information in the subsurface for different scenarios of advection and convective coefficient are discussed briefly. The results show the coupled response of trigonometric variation in air temperature with surface temperatures along with ground water velocity has significant implications for the effects of climate change.

  18. The Future of Subsurface Characterization

    Science.gov (United States)

    Yeh, T. J.

    2006-12-01

    Existing monitoring and characterization technologies can cover only a small fraction of the subsurface, and the information collected cannot be used to effectively manage current and future drought and other water- related problems. Subsurface sciences need a breakthrough "instrument" to greatly expand and deepen our ability to "see into the groundwater basin." The theme of this talk is to promote the idea of collecting data intelligently and analyzing data smartly for characterization of the subsurface at high resolutions beyond the capabilities of current technology. Specifically, we argue that tomographic surveying is a smart approach, which collects data more cost-effectively and less invasively than existing technologies to characterize the subsurface environments. Limitations of a single type (hydrologic, chemical or geophysical) of tomographic survey then motivate fusion of different types of tomographic surveys such that each survey takes advantage of others to overcome its weakness to reach its optimal capability in a reciprocal manner. A basin is an appropriate scale for the purpose of water resources management. Therefore, the field-scale data collection and fusion concept/technology is expanded to basin-scale characterizations. In order to facilitate these basin-scale tomographic surveys, fusion of passive basin-scale tomographys are suggested that exploit recurrent natural stimuli (e,g., lightning, earthquakes, storm events, barometric variations, river- stage variations, etc.) as sources of excitations, along with implementation of sensor networks that provide long-term and spatially distributed monitoring of signals on the land surface and in the subsurface. This vision for basin-scale subsurface characterization undoubtedly faces unprecedented technological challenges and requires interdisciplinary collaborations (e.g., surface and subsurface hydrology, geophysics, geology, geochemist, information technology, applied mathematics, atmospheric

  19. Subsurface Geotechnical Parameters Report

    Energy Technology Data Exchange (ETDEWEB)

    D. Rigby; M. Mrugala; G. Shideler; T. Davidsavor; J. Leem; D. Buesch; Y. Sun; D. Potyondy; M. Christianson

    2003-12-17

    The Yucca Mountain Project is entering a the license application (LA) stage in its mission to develop the nation's first underground nuclear waste repository. After a number of years of gathering data related to site characterization, including activities ranging from laboratory and site investigations, to numerical modeling of processes associated with conditions to be encountered in the future repository, the Project is realigning its activities towards the License Application preparation. At the current stage, the major efforts are directed at translating the results of scientific investigations into sets of data needed to support the design, and to fulfill the licensing requirements and the repository design activities. This document addresses the program need to address specific technical questions so that an assessment can be made about the suitability and adequacy of data to license and construct a repository at the Yucca Mountain Site. In July 2002, the U.S. Nuclear Regulatory Commission (NRC) published an Integrated Issue Resolution Status Report (NRC 2002). Included in this report were the Repository Design and Thermal-Mechanical Effects (RDTME) Key Technical Issues (KTI). Geotechnical agreements were formulated to resolve a number of KTI subissues, in particular, RDTME KTIs 3.04, 3.05, 3.07, and 3.19 relate to the physical, thermal and mechanical properties of the host rock (NRC 2002, pp. 2.1.1-28, 2.1.7-10 to 2.1.7-21, A-17, A-18, and A-20). The purpose of the Subsurface Geotechnical Parameters Report is to present an accounting of current geotechnical information that will help resolve KTI subissues and some other project needs. The report analyzes and summarizes available qualified geotechnical data. It evaluates the sufficiency and quality of existing data to support engineering design and performance assessment. In addition, the corroborative data obtained from tests performed by a number of research organizations is presented to reinforce

  20. Scenario simulation based assessment of subsurface energy storage

    Science.gov (United States)

    Beyer, C.; Bauer, S.; Dahmke, A.

    2014-12-01

    Energy production from renewable sources such as solar or wind power is characterized by temporally varying power supply. The politically intended transition towards renewable energies in Germany („Energiewende") hence requires the installation of energy storage technologies to compensate for the fluctuating production. In this context, subsurface energy storage represents a viable option due to large potential storage capacities and the wide prevalence of suited geological formations. Technologies for subsurface energy storage comprise cavern or deep porous media storage of synthetic hydrogen or methane from electrolysis and methanization, or compressed air, as well as heat storage in shallow or moderately deep porous formations. Pressure build-up, fluid displacement or temperature changes induced by such operations may affect local and regional groundwater flow, geomechanical behavior, groundwater geochemistry and microbiology. Moreover, subsurface energy storage may interact and possibly be in conflict with other "uses" like drinking water abstraction or ecological goods and functions. An utilization of the subsurface for energy storage therefore requires an adequate system and process understanding for the evaluation and assessment of possible impacts of specific storage operations on other types of subsurface use, the affected environment and protected entities. This contribution presents the framework of the ANGUS+ project, in which tools and methods are developed for these types of assessments. Synthetic but still realistic scenarios of geological energy storage are derived and parameterized for representative North German storage sites by data acquisition and evaluation, and experimental work. Coupled numerical hydraulic, thermal, mechanical and reactive transport (THMC) simulation tools are developed and applied to simulate the energy storage and subsurface usage scenarios, which are analyzed for an assessment and generalization of the imposed THMC

  1. Integrated Surface/subsurface flow modeling in PFLOTRAN

    Energy Technology Data Exchange (ETDEWEB)

    Painter, Scott L [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-10-01

    Understanding soil water, groundwater, and shallow surface water dynamics as an integrated hydrological system is critical for understanding the Earth’s critical zone, the thin outer layer at our planet’s surface where vegetation, soil, rock, and gases interact to regulate the environment. Computational tools that take this view of soil moisture and shallow surface flows as a single integrated system are typically referred to as integrated surface/subsurface hydrology models. We extend the open-source, highly parallel, subsurface flow and reactive transport simulator PFLOTRAN to accommodate surface flows. In contrast to most previous implementations, we do not represent a distinct surface system. Instead, the vertical gradient in hydraulic head at the land surface is neglected, which allows the surface flow system to be eliminated and incorporated directly into the subsurface system. This tight coupling approach leads to a robust capability and also greatly simplifies implementation in existing subsurface simulators such as PFLOTRAN. Successful comparisons to independent numerical solutions build confidence in the approximation and implementation. Example simulations of the Walker Branch and East Fork Poplar Creek watersheds near Oak Ridge, Tennessee demonstrate the robustness of the approach in geometrically complex applications. The lack of a robust integrated surface/subsurface hydrology capability had been a barrier to PFLOTRAN’s use in critical zone studies. This work addresses that capability gap, thus enabling PFLOTRAN as a community platform for building integrated models of the critical zone.

  2. Instruments for subsurface monitoring of geothermal subsidence

    Energy Technology Data Exchange (ETDEWEB)

    O' Rourke, J.E.; Ranson, B.B.

    1979-07-01

    The requirements for a subsurface geothermal subsidence instrument were reviewed. Available instruments for monitoring subsurface displacements, both vertical and horizontal, were studied and the most capable instruments identified. Techniques and materials for improving existing or developing new instruments were evaluated. Elements of sensor and signal technology with potential for high temperature monitoring of subsidence were identified. Drawing from these studies, methods to adapt production wells for monitoring were proposed and several new instrumentation systems were conceptually designed. Finally, four instrumentation systems were selected for future development. These systems are: triple sensor induction sensor probe (with casing collar markers); triple sensor gamma ray detector probe (with radioactive markers); triple sensor reed switch probe (with magnet markers); and triple sensor oscillator-type magnet detector probe (with magnet markers). All are designed for use in well casing incorporating slip couplings or bellows sections, although the gamma ray detector probe may also be used in unlined holes. These systems all measure vertical moement. Instruments to measure horizontal displacement due to geothermal subsidence were studied and the required instrument performance was judged to be beyond the state-of-the-art. Thus, no conceptual designs for instruments to monitor horizontal movement are included.

  3. Endoscopic subsurface imaging in tissues

    Energy Technology Data Exchange (ETDEWEB)

    Demos, S G; Staggs, M; Radousky, H B

    2001-02-12

    The objective of this work is to develop endoscopic subsurface optical imaging technology that will be able to image different tissue components located underneath the surface of the tissue at an imaging depth of up to 1 centimeter. This effort is based on the utilization of existing technology and components developed for medical endoscopes with the incorporation of the appropriate modifications to implement the spectral and polarization difference imaging technique. This subsurface imaging technique employs polarization and spectral light discrimination in combination with image processing to remove a large portion of the image information from the outer layers of the tissue which leads to enhancement of the contrast and image quality of subsurface tissue structures.

  4. VISUALIZATION OF REGISTERED SUBSURFACE ANATOMY

    DEFF Research Database (Denmark)

    2010-01-01

    A system and method for visualization of subsurface anatomy includes obtaining a first image from a first camera and a second image from a second camera or a second channel of the first camera, where the first and second images contain shared anatomical structures. The second camera and the second...... channel of the first camera are capable of imaging anatomy beneath the surface in ultra-violet, visual, or infra-red spectrum. A data processor is configured for computing registration of the first image to the second image to provide visualization of subsurface anatomy during surgical procedures...

  5. Integrated geomechanical modelling for deep subsurface damage

    NARCIS (Netherlands)

    Wees, J.D. van; Orlic, B.; Zijl, W.; Jongerius, P.; Schreppers, G.J.; Hendriks, M.

    2001-01-01

    Government, E&P and mining industry increasingly demand fundamental insight and accurate predictions on subsurface and surface deformation and damage due to exploitation of subsurface natural resources, and subsurface storage of energy residues (e.g. CO2). At this moment deformation is difficult to

  6. Subsurface Noble Gas Sampling Manual

    Energy Technology Data Exchange (ETDEWEB)

    Carrigan, C. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sun, Y. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-18

    The intent of this document is to provide information about best available approaches for performing subsurface soil gas sampling during an On Site Inspection or OSI. This information is based on field sampling experiments, computer simulations and data from the NA-22 Noble Gas Signature Experiment Test Bed at the Nevada Nuclear Security Site (NNSS). The approaches should optimize the gas concentration from the subsurface cavity or chimney regime while simultaneously minimizing the potential for atmospheric radioxenon and near-surface Argon-37 contamination. Where possible, we quantitatively assess differences in sampling practices for the same sets of environmental conditions. We recognize that all sampling scenarios cannot be addressed. However, if this document helps to inform the intuition of the reader about addressing the challenges resulting from the inevitable deviations from the scenario assumed here, it will have achieved its goal.

  7. An Appraisal of Coupled Climate Model Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Sperber, K; Gleckler, P; Covey, C; Taylor, K; Bader, D; Phillips, T; Fiorino, M; Achutarao, K

    2004-02-24

    In 2002, the Program for Climate Model Diagnosis and Intercomparison (PCMDI) proposed the concept for a state-of-the-science appraisal of climate models to be performed approximately every two years. Motivation for this idea arose from the perceived needs of the international modeling groups and the broader climate research community to document progress more frequently than provided by the Intergovernmental Panel on Climate Change (IPCC) Assessment Reports. A committee of external reviewers, which included senior researchers from four leading international modeling centers, supported the concept by stating in its review: ''The panel enthusiastically endorses the suggestion that PCMDI develop an independent appraisal of coupled model performance every 2-3 years. This would provide a useful 'mid-course' evaluation of modeling progress in the context of larger IPCC and national assessment activities, and should include both coupled and single-component model evaluations.''

  8. Link between Surface and Subsurface Urban Heat Islands

    Science.gov (United States)

    Benz, Susanne; Bayer, Peter; Olesen, Folke; Goettsche, Frank; Blum, Philipp

    2016-04-01

    Urban heat islands exist in all diverse layers of modern cities, such as surface and subsurface. While both layers are typically investigated separately, the coupling of surface and subsurface urban heat islands is insufficiently understood. Hence, this study focuses on the interrelation of both zones and the influence of additional underground heat sources, such as heated basements, on this interaction. Using satellite derived land surface temperatures and interpolated groundwater temperature measurements the spatial properties of both heat islands are compared. Significant correlations of 0.5 up to more than 0.8 are found between surface and subsurface urban heat islands. If groundwater flow is considered this correlation increases by approximately 10%. Next we analyzed the dissimilarities between both heat islands in order to understand the interaction between the urban surface and subsurface. We find that local groundwater hotspots under the city center and industrial areas are not revealed in satellite derived land surface temperatures. Overall groundwater temperatures are higher than land surface temperatures in 95% of the analyzed area due to the influence of below ground anthropogenic heat sources such as sewage systems, district heating systems, and especially elevated basement temperatures. Thus, an estimation method is proposed that relates groundwater temperatures to mean annual land surface temperatures, building density, and elevated basement temperatures. Using this method regional groundwater temperatures can be accurately estimated with a mean absolute error of 0.9 K. Since land surface temperatures and building densities are available from remote sensing, this method has the potential for a large scale estimations of urban groundwater temperatures. Thus, it is feasible to detect subsurface urban heat islands on a global level and to investigate sustainable geothermal potentials using satellite derived data.

  9. Subsurface deformation in hypervelocity cratering experiments into high-porosity tuffs

    Science.gov (United States)

    Winkler, Rebecca; Poelchau, Michael H.; Moser, Stefan; Kenkmann, Thomas

    2016-10-01

    Hypervelocity impact experiments on porous tuff targets were carried out to determine the effect of porosity on deformation mechanisms in the crater's subsurface. Blocks of Weibern Tuff with about 43% porosity were impacted by 2.5 mm and 12.0 mm diameter steel spheres with velocities between 4.8 km s-1 and 5.6 km s-1. The postimpact subsurface damage was quantified with computer tomography as well as with meso- and microscale analyses of the bisected crater subsurface. The intensity and style of deformation in mineral clasts and the tuff matrix were mapped and their decay with subsurface depth was determined. Subsurface deformation styles include pore space compaction, clast rotation, as well as microfracture formation. Evaluation of the deformation indicates near-surface energy coupling at a calculated depth of burial of 2 projectile diameters (dp), which is in conflict with the crater shape, which displays a deep, central penetration tube. Subsurface damage extends to 2 dp beneath the crater floor in the experiments with 2.5 mm projectiles and increases to 3 dp for 12 mm projectiles. Based on overprinting relationships and the geometrical orientation of deformation features, a sequence of subsurface deformation events was derived (1) matrix compaction, (2) intragranular crack formation in clasts, (3) deformation band formation in the compacted matrix, (4) tensile fracturing.

  10. Controlling Subsurface Fractures and Fluid Flow: A Basic Research Agenda

    Energy Technology Data Exchange (ETDEWEB)

    Pyrak-Nolte, Laura J [Purdue Univ., West Lafayette, IN (United States); DePaolo, Donald J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Pietraß, Tanja [USDOE Office of Science, Washington, DC (United States)

    2015-05-22

    . In response, the Office of Science, through its Office of Basic Energy Science (BES), convened a roundtable consisting of 15 national lab, university and industry geoscience experts to brainstorm basic research areas that underpin the SubTER goals but are currently underrepresented in the BES research portfolio. Held in Germantown, Maryland on May 22, 2015, the round-table participants developed a basic research agenda that is detailed in this report. Highlights include the following: -A grand challenge calling for advanced imaging of stress and geological processes to help understand how stresses and chemical substances are distributed in the subsurface—knowledge that is critical to all aspects of subsurface engineering; -A priority research direction aimed at achieving control of fluid flow through fractured media; -A priority research direction aimed at better understanding how mechanical and geochemical perturbations to subsurface rock systems are coupled through fluid and mineral interactions; -A priority research direction aimed at studying the structure, permeability, reactivity and other properties of nanoporous rocks, like shale, which have become critical energy materials and exhibit important hallmarks of mesoscale materials; -A cross-cutting theme that would accelerate development of advanced computational methods to describe heterogeneous time-dependent geologic systems that could, among other potential benefits, provide new and vastly improved models of hydraulic fracturing and its environmental impacts; -A cross-cutting theme that would lead to the creation of “geo-architected materials” with controlled repeatable heterogeneity and structure that can be tested under a variety of thermal, hydraulic, chemical and mechanical conditions relevant to subsurface systems; -A cross-cutting theme calling for new laboratory studies on both natural and geo-architected subsurface materials that deploy advanced high-resolution 3D imaging and chemical analysis

  11. Calculation notes that support accident scenario and consequence development for the subsurface leak remaining subsurface accident

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, G.W., Westinghouse Hanford

    1996-07-12

    This document supports the development and presentation of the following accident scenario in the TWRS Final Safety Analysis Report: Subsurface Leak Remaining Subsurface. The calculations needed to quantify the risk associated with this accident scenario are included within.

  12. Calculation notes that support accident scenario and consequence development for the subsurface leak remaining subsurface accident

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, G.W., Westinghouse Hanford

    1996-09-19

    This document supports the development and presentation of the following accident scenario in the TWRS Final Safety Analysis Report: Subsurface Leak Remaining Subsurface. The calculations needed to quantify the risk associated with this accident scenario are included within.

  13. Microbial processes and subsurface contaminants

    Science.gov (United States)

    Molz, Fred J.

    A Chapman Conference entitled “Microbial Processes in the Transport, Fate, and In Situ Treatment of Subsurface Contaminants” was held in Snowbird, Utah, October 1-3, 1986. Members of the program committee and session chairmen were Lenore Clesceri (Rensselaer Polytechnic Institute, Troy, N.Y.), David Gibson (University of Texas, Austin), James Mercer (GeoTrans, Inc., Herndon , Va.), Donald Michelsen (Virginia Polytechnic Institute and State University, Blacksburg), Fred Molz (Auburn University, Auburn, Ala.), Bruce Rittman (University of Illinois, Urbana), Gary Sayler (University of Tennessee, Knoxville), and John T. Wilson (U.S. Environmental Protection Agency, Ada, Okla.). The following report attempts to highlight the six sessions that constituted the conference. For additional information, including a bound summary and abstracts, contact Fred J. Molz, Civil Engineering Department, Auburn University, AL 36849 (telephone: 205-826-4321).

  14. On the effects of subsurface parameters on evaporite dissolution (Switzerland).

    Science.gov (United States)

    Zidane, Ali; Zechner, Eric; Huggenberger, Peter; Younes, Anis

    2014-05-01

    Uncontrolled subsurface evaporite dissolution could lead to hazards such as land subsidence. Observed subsidences in a study area of Northwestern Switzerland were mainly due to subsurface dissolution (subrosion) of evaporites such as halite and gypsum. A set of 2D density driven flow simulations were evaluated along 1000 m long and 150 m deep 2D cross sections within the study area that is characterized by tectonic horst and graben structures. The simulations were conducted to study the effect of the different subsurface parameters that could affect the dissolution process. The heterogeneity of normal faults and its impact on the dissolution of evaporites is studied by considering several permeable faults that include non-permeable areas. The mixed finite element method (MFE) is used to solve the flow equation, coupled with the multipoint flux approximation (MPFA) and the discontinuous Galerkin method (DG) to solve the diffusion and the advection parts of the transport equation. Results show that the number of faults above the lower aquifer that contains the salt layer is considered as the most important factor that affects the dissolution compared to the other investigated parameters of thickness of the zone above the halite formation, a dynamic conductivity of the lower aquifer, and varying boundary conditions in the upper aquifer. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Modeling bacterial transport in the subsurface using HP1

    Science.gov (United States)

    Zhang, H.; Olson, M. S.

    2011-12-01

    Bacterial infiltration through the subsurface has been studied experimentally under different conditions of interest and is dependent on a variety of physical, chemical and biological factors, such as solution chemistry, bacterial size and surface properties, and mineral surfaces etc. However, most bacterial transport studies are often not directly relevant to processes occurring in natural systems. Bacteria have been frequently detected and reported in stormwater runoff. Mixing of stormwater runoff with groundwater in the subsurface during infiltration causes changes in solution chemistry, which lead to changes in bacterial surface properties (such as zeta potential) and collector surface charge and properties. This study focuses on bacterial transport as stormwater runoff infiltrates into the subsurface. A microbial reactive transport model is developed using HP1(HYDRUS1D-PHREEQC), which accounts for changes in the physical and chemical factors that control bacterial attachment onto liquid-solid and liquid-air interfaces. Bacterial attachment efficiency to liquid-solid interfaces is considered both under unfavorable conditions, as predicted by DLVO theory and the Maxwell approach coupling both primary and secondary-minima deposition, and under favorable conditions. Bacterial attachment at the liquid-air interface is modeled using mass transfer equations, which vary with changes in the water content profile. Different scenarios are simulated to observe bacterial transport behavior in uniformly and variably unsaturated soil, under high and low surface ponding depths and with varied and constant rates of bacterial attachment. Column transport experiments have been developed to experimentally validate the microbial reactive transport model.

  16. Characterization of the Geology of Subsurface Shallow ...

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: The 2D electrical resistivity imaging study is the rising tool used for characterization of the geology of subsurface diamondiferous shallow conglomerate and geological condition at Baragadi, Panna District,. Madhya Pradesh, India. In the present study, the 2D electrical resistivity imaging of subsurface shallow ...

  17. Fully Integrated Atmospheric, Surface, and Subsurface Model of the California Basin

    Science.gov (United States)

    Davison, J. H.; Hwang, H. T.; Sudicky, E. A.; Mallia, D. V.; Lin, J. C.

    2016-12-01

    The recent drought in the Western United States has crippled agriculture in California's Central Valley. Farmers, facing reduced surface water flow, have turned to groundwater as their primary solution to the water crisis. However, the unsustainable pumping rates seen throughout California have drastically decreased the surface and subsurface water levels. For this reason, we developed a coupled subsurface, surface, and atmospheric model for the entire California Basin that captures the feedbacks between the three domains at an extremely high spatial and temporal resolution. Our coupled model framework integrates HydroGeoSphere (HGS), a fully implicit three-dimensional control-volume finite element surface and variably saturated subsurface model with evapotranspiration process, to Weather Research and Forecasting (WRF), a three-dimensional mesoscale nonhydrostatic atmospheric model. HGS replaces the land surface component within WRF, and provides WRF with the actual evapotranspiration (AET) and soil saturation. In return, WRF provides HGS with the potential evapotranspiration (PET) and precipitation fluxes. The flexible coupling technique allows HGS and WRF to have unique meshing and projection characteristics and links the domains based on their geographic coordinates (i.e., latitude and longitude). The California Basin model successfully simulated similar drawdown rates to the Gravity Recovery and Climate Experiment (GRACE) and replicated the Klamath and Sacramento River hydrographs. Furthermore, our simulation results reproduced field measured precipitation and evapotranspiration. Currently, our coupled California Basin model is the most complete water resource simulator because we combine the surface, subsurface, and atmosphere into a single domain.

  18. Drogue performance evaluation. Part 1: Data acquisition. [for accurate description of subsurface water circulation

    Science.gov (United States)

    Johnson, R. E.

    1975-01-01

    Surface buoy/subsurface drogue drag coupling was investigated. Data acquisition methods and techniques derived from several experimental cruises on the Chesapeake Bay are presented. Four buoys were utilized: three coupled to steel plates rigidly attached to each other at right angles and at various depths; and one spar type that did not require drag plates. Data from these surface floats and the drogue depth combinations were processed. Errors in tracking the surface buoys are discussed.

  19. Impact disruption and recovery of the deep subsurface biosphere

    DEFF Research Database (Denmark)

    Cockell, Charles S.; Voytek, Mary A.; Gronstal, Aaaron L

    2012-01-01

    by the geological disturbances caused by the impact. Microbial abundance is low in buried crater-fill, ocean-resurge, and avalanche deposits despite the presence of redox couples for growth. Coupled with the low hydraulic conductivity, the data suggest the microbial community has not yet recovered from the impact...... 35 million years ago. Microbial enumerations, molecular analysis of microbial enrichment cultures, and geochemical analysis showed recolonization of a deep region of impact-fractured rock that was heated to above the upper temperature limit for life at the time of impact. These results show how......, by fracturing subsurface rocks, impacts can extend the depth of the biosphere. This phenomenon would have provided deep refugia for life on the more heavily bombarded early Earth, and it shows that the deeply fractured regions of impact craters are promising targets to study the past and present habitability...

  20. Impact disruption and recovery of the deep subsurface biosphere

    Science.gov (United States)

    Cockell, Charles S.; Voytek, Mary A.; Gronstal, Aaron L.; Finster, Kai; Kirshtein, Julie D.; Howard, Kieren; Reitner, Joachim; Gohn, Gregory S.; Sanford, Ward E.; Horton, J. Wright; Kallmeyer, Jens; Kelly, Laura; Powars, David S.

    2012-01-01

    Although a large fraction of the world's biomass resides in the subsurface, there has been no study of the effects of catastrophic disturbance on the deep biosphere and the rate of its subsequent recovery. We carried out an investigation of the microbiology of a 1.76 km drill core obtained from the ~35 million-year-old Chesapeake Bay impact structure, USA, with robust contamination control. Microbial enumerations displayed a logarithmic downward decline, but the different gradient, when compared to previously studied sites, and the scatter of the data are consistent with a microbiota influenced by the geological disturbances caused by the impact. Microbial abundance is low in buried crater-fill, ocean-resurge, and avalanche deposits despite the presence of redox couples for growth. Coupled with the low hydraulic conductivity, the data suggest the microbial community has not yet recovered from the impact ~35 million years ago. Microbial enumerations, molecular analysis of microbial enrichment cultures, and geochemical analysis showed recolonization of a deep region of impact-fractured rock that was heated to above the upper temperature limit for life at the time of impact. These results show how, by fracturing subsurface rocks, impacts can extend the depth of the biosphere. This phenomenon would have provided deep refugia for life on the more heavily bombarded early Earth, and it shows that the deeply fractured regions of impact craters are promising targets to study the past and present habitability of Mars.

  1. Equatorial Indian Ocean subsurface current variability in an Ocean General Circulation Model

    Science.gov (United States)

    Gnanaseelan, C.; Deshpande, Aditi

    2017-05-01

    The variability of subsurface currents in the equatorial Indian Ocean is studied using high resolution Ocean General Circulation Model (OGCM) simulations during 1958-2009. February-March eastward equatorial subsurface current (ESC) shows weak variability whereas strong variability is observed in northern summer and fall ESC. An eastward subsurface current with maximum amplitude in the pycnocline is prominent right from summer to winter during strong Indian Ocean Dipole (IOD) years when air-sea coupling is significant. On the other hand during weak IOD years, both the air-sea coupling and the ESC are weak. This strongly suggests the role of ESC on the strength of IOD. The extension of the ESC to the summer months during the strong IOD years strengthens the oceanic response and supports intensification and maintenance of IODs through modulation of air sea coupling. Although the ESC is triggered by equatorial winds, the coupled air-sea interaction associated with IODs strengthens the ESC to persist for several seasons thereby establishing a positive feedback cycle with the surface. This suggests that the ESC plays a significant role in the coupled processes associated with the evolution and intensification of IOD events by cooling the eastern basin and strengthening thermocline-SST (sea surface temperature) interaction. As the impact of IOD events on Indian summer monsoon is significant only during strong IOD years, understanding and monitoring the evolution of ESC during these years is important for summer monsoon forecasting purposes. There is a westward phase propagation of anomalous subsurface currents which persists for a year during strong IOD years, whereas such persistence or phase propagation is not seen during weak IOD years, supporting the close association between ESC and strength of air sea coupling during strong IOD years. In this study we report the processes which strengthen the IOD events and the air sea coupling associated with IOD. It also unravels

  2. PERISCOPE: PERIapsis Subsurface Cave OPtical Explorer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Lunar sub-surface exploration has been a topic of discussion since the Lunar Reconnaissance Orbiter identified openings (cave skylights) on the surface of the moon...

  3. Electrical resistivity determination of subsurface layers, subsoil ...

    African Journals Online (AJOL)

    Electrical resistivity determination of subsurface layers, subsoil competence and soil corrosivity at and engineering site location in Akungba-Akoko, southwestern Nigeria. A I Idornigie, M O Olorunfemi, A A Omitogun ...

  4. Hydrologic Impact Of Subsurface Drainage Of Agricultural Fields

    Science.gov (United States)

    Naz, B. S.; Johannsen, C. J.; Bowling, L. C.

    2005-12-01

    Although subsurface drainage has benefited agricultural productions in many regions of the U.S., there are also concerns about the potential impacts of these systems on watershed hydrology and water quality. This study was focused on tile lines identification and hydrologic response of subsurface drainage systems for the Agronomy Center for Research and Education (ACRE), West Lafayette, Indiana and the Southeastern Purdue Agriculture Center (SEPAC) in southeastern, Indiana. The purpose of the study was to develop and evaluate a remote sensing methodology for automatic detection of tile lines from aerial photographs and to evaluate the Distributed Hydrology Soil-Vegetation Model (DHSVM) to analyze the hydrologic response of tile drained fields. A step-wise approach was developed to first use different image enhancement techniques to increase the visual distinction of tile lines from other details in the image. A new classification model was developed to identify locations of subsurface tiles using a decision tree classifier which compares the multiple data sets such as enhanced image data, land use class, soil drainage class, hydrologic group and surface slope. Accuracy assessment of the predicted tile map was done by comparing the locations of tile drains with existing historic maps and ground-truth data. The overall performance of decision tree classifier model coupled with other pre- and post- classification methods shows that this model can be a very effective tool in identifying tile lines from aerial photographs over large areas of land. Once the tile map was created, the DHSVM was applied to ACRE and SEPAC respectively to see the hydrological impact of the subsurface drainage network. Observed data for 3-years (1998-2000) at ACRE and for 6-years (1993-1998) at SEPAC were used to calibrate and validate the model. The model was simulated for three scenarios: 1) baseline scenario (no tiles), 2) with known tile lines and 3) with tile lines created through

  5. Hydrogen utilization potential in subsurface sediments

    DEFF Research Database (Denmark)

    Adhikari, Rishi Ram; Glombitza, Clemens; Nickel, Julia

    2016-01-01

    Subsurface microbial communities undertake many terminal electron-accepting processes, often simultaneously. Using a tritium-based assay, we measured the potential hydrogen oxidation catalyzed by hydrogenase enzymes in several subsurface sedimentary environments (Lake Van, Barents Sea, Equatorial...... Pacific, and Gulf of Mexico) with different predominant electron-acceptors. Hydrogenases constitute a diverse family of enzymes expressed by microorganisms that utilize molecular hydrogen as a metabolic substrate, product, or intermediate. The assay reveals the potential for utilizing molecular hydrogen...

  6. Microbial life in the deep terrestrial subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Fliermans, C.B. [E.I. DuPont de Nemours and Co., Aiken, SC (United States). Savannah River Lab.; Balkwill, D.L. [Florida State Univ., Tallahassee, FL (United States); Beeman, R.E. [Univ. of Oklahoma, Norman, OK (United States)] [and others

    1988-12-31

    The distribution and function of microorganisms is a vital issue in microbial ecology. The US Department of Energy`s Program, ``Microbiology of the Deep Subsurface,`` concentrates on establishing fundamental scientific information about organisms at depth, and the use of these organisms for remediation of contaminants in deep vadose zone and groundwater environments. This investigation effectively extends the Biosphere hundreds of meters into the Geosphere and has implications to a variety of subsurface activities.

  7. Metalliferous Biosignatures for Deep Subsurface Microbial Activity

    OpenAIRE

    Parnell, John; Brolly, Connor; Spinks, Sam; Bowden, Stephen

    2015-01-01

    The interaction of microbes and metals is widely assumed to have occurred in surface or very shallow subsurface environments. However new evidence suggests that much microbial activity occurs in the deep subsurface. Fluvial, lacustrine and aeolian ?red beds? contain widespread centimetre-scale reduction spheroids in which a pale reduced spheroid in otherwise red rocks contains a metalliferous core. Most of the reduction of Fe (III) in sediments is caused by Fe (III) reducing bacteria. They ha...

  8. Extracting subsurface fingerprints using optical coherence tomography

    CSIR Research Space (South Africa)

    Akhoury, SS

    2015-02-01

    Full Text Available Subsurface Fingerprints using Optical Coherence Tomography Sharat Saurabh Akhoury, Luke Nicholas Darlow Modelling and Digital Science, Council for Scientific and Industrial Research, Pretoria, South Africa Abstract Physiologists have found... that fingerprint patterns exist in the inner layers (viz. papillary junction) of the skin of the fingertip. However, conventional acquisition systems do not have capabilities to extract fingerprints at subsurface layers of the finger for use in identity...

  9. [Electronic cigarette : state of the science about toxicological aspects].

    Science.gov (United States)

    Deville, M; Charlier, C

    2017-01-01

    Electronic cigarettes (e-cigarettes) are presented as a healthier alternative to tobacco smoking. They are designed to contain a solution which is heated to produce an aerosol inhaled by the user. The liquid is mainly composed of propylene glycol, glycerol, flavours and, in some cases, nicotine. Except for nicotine, which can be fatal when ingested at high dose, these components are generally considered as safe. However, the potential effect of long term exposure to inhaled propylene glycol is unknown at this time. As an advantage, toxic compounds responsible for the noxiousness of tobacco smoking (nitrosamines, metals, formaldehyde, carbon monoxide …) are either absent, or present in the smoke of e-cigarette at levels far less compared to conventional cigarette smoke. Finally, efficacy of e-cigarette as a tool for smoking cessation stays to be proven.

  10. Climate change and older Americans: state of the science.

    Science.gov (United States)

    Gamble, Janet L; Hurley, Bradford J; Schultz, Peter A; Jaglom, Wendy S; Krishnan, Nisha; Harris, Melinda

    2013-01-01

    Older adults make up 13% of the U.S. population, but are projected to account for 20% by 2040. Coinciding with this demographic shift, the rate of climate change is accelerating, bringing rising temperatures; increased risk of floods, droughts, and wildfires; stronger tropical storms and hurricanes; rising sea levels; and other climate-related hazards. Older Americans are expected to be located in places that may be relatively more affected by climate change, including coastal zones and large metropolitan areas. The objective of this review is to assess the vulnerability of older Americans to climate change and to identify opportunities for adaptation. We performed an extensive literature survey and summarized key findings related to demographics; climate stressors relevant to older adults; factors contributing to exposure, sensitivity, and adaptive capacity; and adaptation strategies. A range of physiological and socioeconomic factors make older adults especially sensitive to and/or at risk for exposure to heat waves and other extreme weather events (e.g., hurricanes, floods, droughts), poor air quality, and infectious diseases. Climate change may increase the frequency or severity of these events. Older Americans are likely to be especially vulnerable to stressors associated with climate change. Although a growing body of evidence reports the adverse effects of heat on the health of older adults, research gaps remain for other climate-related risks. We need additional study of the vulnerability of older adults and the interplay of vulnerability, resilience, and adaptive responses to projected climate stressors.

  11. Climate Change and Older Americans: State of the Science

    OpenAIRE

    Gamble, Janet L.; Hurley, Bradford J.; Schultz, Peter A.; Jaglom, Wendy S.; Krishnan, Nisha; Harris, Melinda

    2012-01-01

    Background: Older adults make up 13% of the U.S. population, but are projected to account for 20% by 2040. Coinciding with this demographic shift, the rate of climate change is accelerating, bringing rising temperatures; increased risk of floods, droughts, and wildfires; stronger tropical storms and hurricanes; rising sea levels; and other climate-related hazards. Older Americans are expected to be located in places that may be relatively more affected by climate change, including coastal zon...

  12. Lifestyle interventions for "diabesity": the state of the science.

    Science.gov (United States)

    Mobley, Connie C

    2004-03-01

    Lifestyle is an expression of individual choices and their interaction with the environment and is closely associated with risks for obesity, diabetes, and cardiovascular disorders. If taken cumulatively this syndrome may be referred to as "diabesity." The escalating prevalence of obesity among both children and adults is one modifiable dominant risk factor in this triad. An increase in body weight of approximately 2.2 pounds (1 kg) has been shown to increase risk for diabetes by 4.5%. Alternatively, a 5% to 10% decrease in body weight improves diabetes control. The metabolic syndrome of diabetes has been described as a consortium of conditions including dyslipidemia, hypertension, and abdominal obesity. In randomized controlled clinical trials, dietary and physical activity interventions have been shown to be effective in decreasing risk for, as well as delaying conversion to, these disorders. Since 1977, 4 hallmark multisite clinical trials have been conducted in the United States, the United Kingdom, and Finland confirming that improved glycemic and hypertensive control of patients through lifestyle interventions can have positive effects on associated complications and longitudinal outcomes. A fifth robust and well-controlled study is currently being conducted in multiple sites in the United States. Dietary behaviors are modulating factors not only in these metabolic and systemic conditions but also in risk for oral diseases such as dental caries. The association between obesity, diabetes, cardiovascular diseases, and oral health status may be linked by these lifestyle behaviors. Promotion of weight management involves approaches that include diet, physical activity, and behavior modification. Established effective guidelines within these domains may be applicable to current practice and future studies designed to examine the associations between diabesity and oral health status.

  13. #2) Sensor Technology-State of the Science | Science ...

    Science.gov (United States)

    Establish market surveys of commercially-available air quality sensorsConduct an extensive literature survey describing the state of sensor technologiesInvestigate emerging technologies and their potential to meet future air quality monitoring needs for the Agency as well as other partners/stakeholders Develop sensor user guidesEducate sensor developers/sensors users on the state of low cost censorsFacilitate knowledge transfer to Federal/Regional/State air quality associatesWork directly with sensor developers to dramatically speed up the development of next generation air monitoring Support ORD’s Sensor Roadmap by focusing on areas of highest priority (NAAQS, Air Toxics, Citizen Science)Establish highly integrated research efforts across ORD and its partners (internal/external) to ensure consistent The National Exposure Research Laboratory (NERL) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in support of EPA mission to protect human health and the environment. HEASD research program supports Goal 1 (Clean Air) and Goal 4 (Healthy People) of EPA strategic plan. More specifically, our division conducts research to characterize the movement of pollutants from the source to contact with humans. Our multidisciplinary research program produces Methods, Measurements, and Models to identify relationships between and characterize processes that link source emissions, environmental concentrations, human exposures, and target-tissue dose.

  14. Aviation Noise Impacts: State of the Science.(Review Article)

    National Research Council Canada - National Science Library

    Sparrow, Victor; Basner, Mathias; Janssen, Sabine; Hileman, James; Hansell, Anna; Clark, Charlotte; Shepherd, Kevin

    2017-01-01

    .... It can cause community annoyance, disrupt sleep, adversely affect academic performance of children, and could increase the risk for cardiovascular disease of people living in the vicinity of airports...

  15. Nursing research and HIV infection: state-of-the-science.

    Science.gov (United States)

    Goldrick, B A; Baigis, J A; Larsen, J; Lemert, J L

    2000-01-01

    To provide an update of the nursing research literature on HIV infection and to develop an HIV/AIDS database using arcs computer software. Nursing research literature from 1986 through 1997 on human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS) was reviewed. With an emphasis on client-focused research, 246 studies were entered into the arcs HIV/AIDS database. Analysis of over 1,000 citations in the HIV/AIDS nursing research literature over the past decade indicated that 22% (n = 219) of the nursing studies were client- or patient-focused; 29% (n = 292) were risk-group focused; and 49% (n = 492) were provider-focused. Of the 246 studies entered into the arcs HIV/AIDS database, 88 (35.7%) were classified in the psychologic domain, 65 (26.4%) in the physiologic domain, 24 (9.7%) in the behavioral domain, and 25 (10%) in the social domain. In addition, 17 (6.9%) of the studies were classified in the quality of life domain, and 27 (10.9%) in the stage of HIV disease domain. The majority (53%) of the 246 studies (n = 131) were correlational, 86 (35%) were descriptive, and 29 (12%) had experimental or quasi-experimental designs. Although nursing studies have described some of the problems that affect HIV-infected people, further research is needed, particularly related to clinical interventions.

  16. Arsenic and Environmental Health: State of the Science and ...

    Science.gov (United States)

    Background: Exposure to inorganic and organic arsenic compounds is a major public health problem that affects hundreds of millions of people worldwide. Exposure to arsenic is associated with cancer and noncancer effects in nearly every organ in the body, and evidence is mounting for health effects at lower levels of arsenic exposure than previously thought. Building from a tremendous knowledge base with > 1,000 scientific papers published annually with “arsenic” in the title, the question becomes, what questions would best drive future research directions? Objectives: The objective is to discuss emerging issues in arsenic research and identify data gaps across disciplines. Methods: The National Institutes of Health’s National Institute of Environmental Health Sciences Superfund Research Program convened a workshop to identify emerging issues and research needs to address the multi-faceted challenges related to arsenic and environmental health. This review summarizes information captured during the workshop. Discussion: More information about aggregate exposure to arsenic is needed, including the amount and forms of arsenic found in foods. New strategies for mitigating arsenic exposures and related health effects range from engineered filtering systems to phytogenetics and nutritional interventions. Furthermore, integration of omics data with mechanistic and epidemiological data is a key step toward the goal of linking biomarkers of exposure and suscepti

  17. Forensic Nursing State of the Science: Research and Practice Opportunities.

    Science.gov (United States)

    Drake, Stacy A; Koetting, Cathy; Thimsen, Kathi; Downing, Nancy; Porta, Carolyn; Hardy, Peggy; Valentine, Julie L; Finn, Cris; Engebretson, Joan

    The International Association of Forensic Nurses (IAFN) is the only nursing organization advancing the forensic nursing specialty. The organization seeks to advance the profession, and one mechanism for doing so is development of a research agenda. The purpose of this action-based research study was to aid in the development of a forensic nursing research agenda. The study was carried out in two integral stages: (a) focus groups with IAFN members attending the annual conference and (b) reviewing posted IAFN member listserv material. The findings of this study identified similar gaps of other nursing specialties experiencing "growing pains," including role confusion and variation in educational preparation. Findings from this study will inform development of the IAFN 5-year research agenda to advance forensic nursing science and evidence-based practice.

  18. VIRTUAL SYMPOSIUM: STATE OF THE SCIENCE--PPCPS ...

    Science.gov (United States)

    This document provides a brief summary of how this pioneering meeting for the ACS was conducted, as well as some perspective and insights that could prove useful for those who might beinterested in organizing and hosting their own

  19. Hypoxic Hypoxia at Moderate Altitudes: State of the Science

    Science.gov (United States)

    2011-05-01

    respiratory surfaces. The table illustrates partial pressure of carbon dioxide (PACO2) and PAO2 at different altitudes when breathing air and when...SaO2 is approximately 87 to 90%. The significance of these values can be illustrated graphically by considering the oxyhemoglobin dissociation...decreases in some performance parameters. For example, Schlaepfer, Bartsch , and Fisch (1992) found an increase in visual perception with mild hypoxia

  20. Combination treatment for nicotine dependence: state of the science.

    Science.gov (United States)

    Ingersoll, Karen S; Cohen, Jessye

    2005-01-01

    Both nicotine replacement and sustained-release buproprion double the odds of achieving short- and moderate-term abstinence from nicotine. However, questions remain about the efficacy of combining pharmacotherapies. Our purposes were to review the evidence for (1) combined pharmacotherapy and (2) multimodal treatment combining pharmacotherapy and behavioral treatment and to recommend combinations of treatments to reduce nicotine dependence. Combining first-line pharmacotherapies with each other or with investigational drugs shows little benefit. In contrast, trials combining specific behavioral treatments with first-line pharmacotherapies show enhanced smoking cessation rates, but benefits are not seen in all populations. We recommend future directions for research, including better specification of behavioral components and further examination of the length and timing of treatment.

  1. Combination Treatment for Nicotine Dependence: State of the Science

    OpenAIRE

    INGERSOLL, KAREN S.; COHEN, JESSYE

    2005-01-01

    Both nicotine replacement and sustained-release buproprion double the odds of achieving short- and moderate-term abstinence from nicotine. However, questions remain about the efficacy of combining pharmacotherapies. Our purposes were to review the evidence for (1) combined pharmacotherapy and (2) multimodal treatment combining pharmacotherapy and behavioral treatment and to recommend combinations of treatments to reduce nicotine dependence. Combining first-line pharmacotherapies with each oth...

  2. Falls in the community: state of the science

    Science.gov (United States)

    Hester, Amy L; Wei, Feifei

    2013-01-01

    Falls and fall-related injuries among older community-dwelling adults continue to be a major health concern in the US. Falls are the leading cause of disability and trauma-related death in persons over 65 years of age. This article discusses current approaches in community fall management and challenges with these approaches, and offers some insight for community providers regarding this issue. PMID:23776331

  3. Soil moisture remote sensing: State of the science

    Science.gov (United States)

    Satellites (e.g., SMAP, SMOS) using passive microwave techniques, in particular at L band frequency, have shown good promise for global mapping of near-surface (0-5 cm) soil moisture at a spatial resolution of 25-40 km and temporal resolution of 2-3 days. C- and X-band soil moisture records date bac...

  4. Conowingo Reservoir Sedimentation and Chesapeake Bay: State of the Science.

    Science.gov (United States)

    Cerco, Carl F

    2016-05-01

    The Conowingo Reservoir is situated on the Susquehanna River, immediately upstream of Chesapeake Bay, the largest estuary in the United States. Sedimentation in the reservoir provides an unintended benefit to the bay by preventing sediments, organic matter, and nutrients from entering the bay. The sediment storage capacity of the reservoir is nearly exhausted, however, and the resulting increase in loading of sediments and associated materials is a potential threat to Chesapeake Bay water quality. In response to this threat, the Lower Susquehanna River Watershed Assessment was conducted. The assessment indicates the reservoir is in a state of "dynamic equilibrium" in which sediment loads from the upstream watershed to the reservoir are balanced by sediments leaving the reservoir. Increased sediment loads are not a threat to bay water quality. Increased loads of associated organic matter and nutrients are, however, detrimental. Bottom-water dissolved oxygen declines of 0.1 to 0.2 g m are projected as a result of organic matter oxidation and enhanced eutrophication. The decline is small relative to normal variations but results in violations of standards enforced in a recently enacted total maximum daily load. Enhanced reductions in nutrient loads from the watershed are recommended to offset the decline in water quality caused by diminished retention in the reservoir. The assessment exposed several knowledge gaps that require additional investigation, including the potential for increased loading at flows below the threshold for reservoir scour and the nature and reactivity of organic matter and nutrients scoured from the reservoir bottom. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  5. Nutrition and oral infectious diseases: state of the science.

    Science.gov (United States)

    Enwonwu, Cyril O; Phillips, Reshma S; Falkler, William A

    2002-05-01

    Immunological competence and nutritional status are two of the most important determinants of morbidity and mortality. Oral diseases, particularly inflammatory periodontal lesions, are caused by viruses and specific periodontopathic bacteria. Paradoxically, the production of cytokines and oxidant molecules, which are supposed to be part of a highly effective mechanism for combating the periodontal pathogens, may damage the host. Malnutrition consistently impairs innate and adaptive defenses of the host, including phagocytic function, cell-mediated immunity, complement system, secretory antibody, and cytokine production and function. In protein-energy malnutrition, there are marked changes in the oral microbial ecology resulting in a preponderance of pathogenic anaerobic organisms, increased propensity of bacteria to bind to oral mucosal cells, attenuation of acute phase protein response, and dysfunction of the cytokine system. Cellular depletion of antioxidant nutrients promotes immunosuppression, accelerated replication rate of ribonucleic acid viruses, and increased disease progression. Therefore, malnutrition can intensify the severity of oral infections and may lead to their evolution into life-threatening diseases.

  6. Measuring voice outcomes: state of the science review.

    Science.gov (United States)

    Carding, Pau N; Wilson, J A; MacKenzie, K; Deary, I J

    2009-08-01

    Researchers evaluating voice disorder interventions currently have a plethora of voice outcome measurement tools from which to choose. Faced with such a wide choice, it would be beneficial to establish a clear rationale to guide selection. This article reviews the published literature on the three main areas of voice outcome assessment: (1) perceptual rating of voice quality, (2) acoustic measurement of the speech signal and (3) patient self-reporting of voice problems. We analysed the published reliability, validity, sensitivity to change and utility of the common outcome measurement tools in each area. From the data, we suggest that routine voice outcome measurement should include (1) an expert rating of voice quality (using the Grade-Roughness-Breathiness-Asthenia-Strain rating scale) and (2) a short self-reporting tool (either the Vocal Performance Questionnaire or the Vocal Handicap Index 10). These measures have high validity, the best reported reliability to date, good sensitivity to change data and excellent utility ratings. However, their application and administration require attention to detail. Acoustic measurement has arguable validity and poor reliability data at the present time. Other areas of voice outcome measurement (e.g. stroboscopy and aerodynamic phonatory measurements) require similarly detailed research and analysis.

  7. First Science Results from MARSIS Subsurface Sounding

    Science.gov (United States)

    Plaut, J. J.; Picardi, G.; Calabrese, D.; Cicchetti, A.; Clifford, S.; Farrell, W.; Federico, C.; Frigeri, A.; Gurnett, D.; Huff, R.; Ivanov, A.; Johnson, W.; Jordan, R.; Kirchner, D.; Leuschen, C.; Masdea, A.; Orosei, R.; Phillips, R.; Safaeinili, A.; Seu, R.; Stofan, E.; Watters, T.

    2005-12-01

    The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS), aboard the Mars Express orbiter, began routine science observations in early July, 2005. The radar operates in two primary modes, subsurface sounding and ionospheric sounding. The objective of the subsurface experiment is to detect and characterize subsurface material discontinuities in the upper several km of the martian crust, some of which may be related to the presence of water (liquid or solid). In the subsurface sounding mode, one or two of four frequency bands in the range of 1.3-5.5 MHz can be selected. The lower frequency bands are expected to penetrate more deeply, but cannot be used when the dayside ionosphere is beneath the spacecraft. The orbit of Mars Express oscillates between periods of day and night peripases; July and August, 2005 included some nightside coverage, while September-November are dayside only. Subsurface sounding data have a lateral resolution of 5-10 km and a vertical resolution of 100 m in free space (about 50 m in crustal materials). The MARSIS radar has been performing nominally since turn-on. Echoes from the surface are typically strong, with signal-to-noise ratios in the range of 30-50 dB. Later returns from off-nadir topographic clutter are evident and easily modeled using MOLA topography data. Many late echoes are observed that cannot be explained as topographic clutter. These features are under investigation as potential subsurface interfaces. As the periapsis of the Mars Express orbit migrates toward the south pole, the polar layered deposits and related landforms will be observed by MARSIS on the nightside. In addition, numerous targets of interest in the southern mid-latitudes will be acquired during the nightside, including the floors of Hellas and Argyre basins, and the regions of strong remnant crustal magnetization.

  8. Quantifying induced effects of subsurface renewable energy storage

    Science.gov (United States)

    Bauer, Sebastian; Beyer, Christof; Pfeiffer, Tilmann; Boockmeyer, Anke; Popp, Steffi; Delfs, Jens-Olaf; Wang, Bo; Li, Dedong; Dethlefsen, Frank; Dahmke, Andreas

    2015-04-01

    New methods and technologies for energy storage are required for the transition to renewable energy sources. Subsurface energy storage systems such as salt caverns or porous formations offer the possibility of hosting large amounts of energy or substance. When employing these systems, an adequate system and process understanding is required in order to assess the feasibility of the individual storage option at the respective site and to predict the complex and interacting effects induced. This understanding is the basis for assessing the potential as well as the risks connected with a sustainable usage of these storage options, especially when considering possible mutual influences. For achieving this aim, in this work synthetic scenarios for the use of the geological underground as an energy storage system are developed and parameterized. The scenarios are designed to represent typical conditions in North Germany. The types of subsurface use investigated here include gas storage and heat storage in porous formations. The scenarios are numerically simulated and interpreted with regard to risk analysis and effect forecasting. For this, the numerical simulators Eclipse and OpenGeoSys are used. The latter is enhanced to include the required coupled hydraulic, thermal, geomechanical and geochemical processes. Using the simulated and interpreted scenarios, the induced effects are quantified individually and monitoring concepts for observing these effects are derived. This presentation will detail the general investigation concept used and analyze the parameter availability for this type of model applications. Then the process implementation and numerical methods required and applied for simulating the induced effects of subsurface storage are detailed and explained. Application examples show the developed methods and quantify induced effects and storage sizes for the typical settings parameterized. This work is part of the ANGUS+ project, funded by the German Ministry

  9. Deglacial Tropical Atlantic subsurface warming links ocean circulation variability to the West African Monsoon.

    Science.gov (United States)

    Schmidt, Matthew W; Chang, Ping; Parker, Andrew O; Ji, Link; He, Feng

    2017-11-13

    Multiple lines of evidence show that cold stadials in the North Atlantic were accompanied by both reductions in Atlantic Meridional Overturning Circulation (AMOC) and collapses of the West African Monsoon (WAM). Although records of terrestrial change identify abrupt WAM variability across the deglaciation, few studies show how ocean temperatures evolved across the deglaciation. To identify the mechanism linking AMOC to the WAM, we generated a new record of subsurface temperature variability over the last 21 kyr based on Mg/Ca ratios in a sub-thermocline dwelling planktonic foraminifera in an Eastern Equatorial Atlantic (EEA) sediment core from the Niger Delta. Our subsurface temperature record shows abrupt subsurface warming during both the Younger Dryas (YD) and Heinrich Event 1. We also conducted a new transient coupled ocean-atmosphere model simulation across the YD that better resolves the western boundary current dynamics and find a strong negative correlation between AMOC strength and EEA subsurface temperatures caused by changes in ocean circulation and rainfall responses that are consistent with the observed WAM change. Our combined proxy and modeling results provide the first evidence that an oceanic teleconnection between AMOC strength and subsurface temperature in the EEA impacted the intensity of the WAM on millennial time scales.

  10. Subsurface flow in a soil-mantled subtropical dolomite karst slope: A field rainfall simulation study

    Science.gov (United States)

    Fu, Z. Y.; Chen, H. S.; Zhang, W.; Xu, Q. X.; Wang, S.; Wang, K. L.

    2015-12-01

    Soil and epikarst co-evolve resulting in complex structures, but their coupled structural effects on hydrological processes are poorly understood in karst regions. This study examined the plot-scale subsurface flow characteristics from an integrated soil-epikarst system perspective in a humid subtropical cockpit karst region of Southwest China. A trench was excavated to the epikarst lower boundary for collecting individual subsurface flows in five sections with different soil thicknesses. Four field rainfall simulation experiments were carried out under different initial moisture conditions (dry and wet) and rainfall intensities (114 mm h- 1 (high) and 46 mm h- 1 (low) on average). The soil-epikarst system was characterized by shallow soil overlaying a highly irregular epikarst surface with a near-steady infiltration rate of about 35 mm h- 1. The subsurface flows occurred mainly along the soil-epikarst interface and were dominated by preferential flow. The subsurface flow hydrographs showed strong spatial variability and had high steady-state coefficients (0.52 and 0.36 for high and low rainfall intensity events). Irregular epikarst surface combining with high vertical drainage capacity resulted in high threshold rainfall depths for subsurface flows: 67 mm and 263 mm for initial wet and dry conditions, respectively. The above results evidenced that the irregular and permeable soil-epikarst interface was a crucial component of soil-epikarst architecture and consequently should be taken into account in the hydrological modeling for karst regions.

  11. A new high-resolution electromagnetic method for subsurface imaging

    Science.gov (United States)

    Feng, Wanjie

    For most electromagnetic (EM) geophysical systems, the contamination of primary fields on secondary fields ultimately limits the capability of the controlled-source EM methods. Null coupling techniques were proposed to solve this problem. However, the small orientation errors in the null coupling systems greatly restrict the applications of these systems. Another problem encountered by most EM systems is the surface interference and geologic noise, which sometimes make the geophysical survey impossible to carry out. In order to solve these problems, the alternating target antenna coupling (ATAC) method was introduced, which greatly removed the influence of the primary field and reduced the surface interference. But this system has limitations on the maximum transmitter moment that can be used. The differential target antenna coupling (DTAC) method was proposed to allow much larger transmitter moments and at the same time maintain the advantages of the ATAC method. In this dissertation, first, the theoretical DTAC calculations were derived mathematically using Born and Wolf's complex magnetic vector. 1D layered and 2D blocked earth models were used to demonstrate that the DTAC method has no responses for 1D and 2D structures. Analytical studies of the plate model influenced by conductive and resistive backgrounds were presented to explain the physical phenomenology behind the DTAC method, which is the magnetic fields of the subsurface targets are required to be frequency dependent. Then, the advantages of the DTAC method, e.g., high-resolution, reducing the geologic noise and insensitive to surface interference, were analyzed using surface and subsurface numerical examples in the EMGIMA software. Next, the theoretical advantages, such as high resolution and insensitive to surface interference, were verified by designing and developing a low-power (moment of 50 Am 2) vertical-array DTAC system and testing it on controlled targets and scaled target coils. At last, a

  12. Stochastic and deterministic assembly processes in subsurface microbial communities.

    Science.gov (United States)

    Stegen, James C; Lin, Xueju; Konopka, Allan E; Fredrickson, James K

    2012-09-01

    A major goal of microbial community ecology is to understand the forces that structure community composition. Deterministic selection by specific environmental factors is sometimes important, but in other cases stochastic or ecologically neutral processes dominate. Lacking is a unified conceptual framework aiming to understand why deterministic processes dominate in some contexts but not others. Here we work toward such a framework. By testing predictions derived from general ecological theory we aim to uncover factors that govern the relative influences of deterministic and stochastic processes. We couple spatiotemporal data on subsurface microbial communities and environmental parameters with metrics and null models of within and between community phylogenetic composition. Testing for phylogenetic signal in organismal niches showed that more closely related taxa have more similar habitat associations. Community phylogenetic analyses further showed that ecologically similar taxa coexist to a greater degree than expected by chance. Environmental filtering thus deterministically governs subsurface microbial community composition. More importantly, the influence of deterministic environmental filtering relative to stochastic factors was maximized at both ends of an environmental variation gradient. A stronger role of stochastic factors was, however, supported through analyses of phylogenetic temporal turnover. Although phylogenetic turnover was on average faster than expected, most pairwise comparisons were not themselves significantly non-random. The relative influence of deterministic environmental filtering over community dynamics was elevated, however, in the most temporally and spatially variable environments. Our results point to general rules governing the relative influences of stochastic and deterministic processes across micro- and macro-organisms.

  13. Twin screw subsurface and surface multiphase pumps

    Energy Technology Data Exchange (ETDEWEB)

    Dass, P. [CAN-K GROUP OF COMPANIES, Edmonton, Alberta (Canada)

    2011-07-01

    A new subsurface twin screw multiphase pump has been developed to replace ESP and other artificial lift technologies. This technology has been under development for a few years, has been field tested and is now going for commercial applications. The subsurface twin screw technology consists of a pair of screws that do not touch and can be run with a top drive or submersible motor; and it carries a lot of benefits. This technology is easy to install and its low slippage makes it highly efficient with heavy oil. In addition twin screw multiphase pumps are capable of handling high viscosity fluids and thus their utilization can save water when used in thermal applications. It also induces savings of chemicals because asphaltenes do not break down easily as well as a reduction in SOR. The subsurface twin screw multiphase pump presented herein is an advanced technology which could be used in thermal applications.

  14. Microbial activities in deep subsurface environments

    Energy Technology Data Exchange (ETDEWEB)

    Phelps, T.J.; Raione, E.G.; White, D.C. [Univ. of Tennessee, Knoxville, TN (United States). Inst. for Applied Microbiology]|[Oak Ridge National Lab., Knoxville, TN (United States); Fliermans, C.B. [E.I. DuPont de Nemours and Co., Aiken, SC (United States). Savannah River Plant

    1988-12-31

    Activities of microorganisms residing in terrestrial deep subsurface sediments were examined in forty-six sediment samples from three aseptically sampled boreholes. Radiolabeled time course experiments assessing in situ microbial activities were initiated within 30 minutes of core recovery. [{sup 14}C-1-] Acetate incorporation into lipids. [methyl-{sup 3}H-]thymidine incorporation into DNA, [{sup 14}C-2-]acetate and [{sup 14}C-U-]glucose mineralization in addition to microbial enrichment and enumeration studies were examined in surface and subsurface sediments. Surface soils contained the greatest biomass and activities followed by the shallow aquifer zones. Water saturated subsurface sediments exhibited three to four orders of magnitude greater activity and culturable microorganisms than the dense clay zones. Regardless of depth, sediments which contained more than 20% clays exhibited the lowest activities and culturable microorganisms.

  15. Autonomous microexplosives subsurface tracing system final report.

    Energy Technology Data Exchange (ETDEWEB)

    Engler, Bruce Phillip; Nogan, John; Melof, Brian Matthew; Uhl, James Eugene; Dulleck, George R., Jr.; Ingram, Brian V.; Grubelich, Mark Charles; Rivas, Raul R.; Cooper, Paul W.; Warpinski, Norman Raymond; Kravitz, Stanley H.

    2004-04-01

    The objective of the autonomous micro-explosive subsurface tracing system is to image the location and geometry of hydraulically induced fractures in subsurface petroleum reservoirs. This system is based on the insertion of a swarm of autonomous micro-explosive packages during the fracturing process, with subsequent triggering of the energetic material to create an array of micro-seismic sources that can be detected and analyzed using existing seismic receiver arrays and analysis software. The project included investigations of energetic mixtures, triggering systems, package size and shape, and seismic output. Given the current absence of any technology capable of such high resolution mapping of subsurface structures, this technology has the potential for major impact on petroleum industry, which spends approximately $1 billion dollar per year on hydraulic fracturing operations in the United States alone.

  16. Subsurface Contaminants Focus Area annual report 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    In support of its vision for technological excellence, the Subsurface Contaminants Focus Area (SCFA) has identified three strategic goals. The three goals of the SCFA are: Contain and/or stabilize contamination sources that pose an imminent threat to surface and ground waters; Delineate DNAPL contamination in the subsurface and remediate DNAPL-contaminated soils and ground water; and Remove a full range of metal and radionuclide contamination in soils and ground water. To meet the challenges of remediating subsurface contaminants in soils and ground water, SCFA funded more than 40 technologies in fiscal year 1997. These technologies are grouped according to the following product lines: Dense Nonaqueous-Phase Liquids; Metals and Radionuclides; Source Term Containment; and Source Term Remediation. This report briefly describes the SCFA 1997 technologies and showcases a few key technologies in each product line.

  17. Improving the biodegradative capacity of subsurface bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Romine, M.F.; Brockman, F.J.

    1993-04-01

    The continual release of large volumes of synthetic materials into the environment by agricultural and industrial sources over the last few decades has resulted in pollution of the subsurface environment. Cleanup has been difficult because of the relative inaccessibility of the contaminants caused by their wide dispersal in the deep subsurface, often at low concentrations and in large volumes. As a possible solution for these problems, interest in the introduction of biodegradative bacteria for in situ remediation of these sites has increased greatly in recent years (Timmis et al. 1988). Selection of biodegradative microbes to apply in such cleanup is limited to those strains that can survive among the native bacterial and predator community members at the particular pH, temperature, and moisture status of the site (Alexander, 1984). The use of microorganisms isolated from subsurface environments would be advantageous because the organisms are already adapted to the subsurface conditions. The options are further narrowed to strains that are able to degrade the contaminant rapidly, even in the presence of highly recalcitrant anthropogenic waste mixtures, and in conditions that do not require addition of further toxic compounds for the expression of the biodegradative capacity (Sayler et al. 1990). These obstacles can be overcome by placing the genes of well-characterized biodegradative enzymes under the control of promoters that can be regulated by inexpensive and nontoxic external factors and then moving the new genetic constructs into diverse groups of subsurface microbes. ne objective of this research is to test this hypothesis by comparing expression of two different toluene biodegradative enzymatic pathways from two different regulatable promoters in a variety of subsurface isolates.

  18. MSTS - Multiphase Subsurface Transport Simulator theory manual

    Energy Technology Data Exchange (ETDEWEB)

    White, M.D.; Nichols, W.E.

    1993-05-01

    The US Department of Energy, through the Yucca Mountain Site Characterization Project Office, has designated the Yucca Mountain site in Nevada for detailed study as the candidate US geologic repository for spent nuclear fuel and high-level radioactive waste. Site characterization will determine the suitability of the Yucca Mountain site for the potential waste repository. If the site is determined suitable, subsequent studies and characterization will be conducted to obtain authorization from the Nuclear Regulatory Commission to construct the potential waste repository. A principal component of the characterization and licensing processes involves numerically predicting the thermal and hydrologic response of the subsurface environment of the Yucca Mountain site to the potential repository over a 10,000-year period. The thermal and hydrologic response of the subsurface environment to the repository is anticipated to include complex processes of countercurrent vapor and liquid migration, multiple-phase heat transfer, multiple-phase transport, and geochemical reactions. Numerical simulators based on mathematical descriptions of these subsurface phenomena are required to make numerical predictions of the thermal and hydrologic response of the Yucca Mountain subsurface environment The engineering simulator called the Multiphase Subsurface Transport Simulator (MSTS) was developed at the request of the Yucca Mountain Site Characterization Project Office to produce numerical predictions of subsurface flow and transport phenomena at the potential Yucca Mountain site. This document delineates the design architecture and describes the specific computational algorithms that compose MSTS. Details for using MSTS and sample problems are given in the {open_quotes}User`s Guide and Reference{close_quotes} companion document.

  19. Induction heaters used to heat subsurface formations

    Science.gov (United States)

    Nguyen, Scott Vinh [Houston, TX; Bass, Ronald M [Houston, TX

    2012-04-24

    A heating system for a subsurface formation includes an elongated electrical conductor located in the subsurface formation. The electrical conductor extends between at least a first electrical contact and a second electrical contact. A ferromagnetic conductor at least partially surrounds and at least partially extends lengthwise around the electrical conductor. The electrical conductor, when energized with time-varying electrical current, induces sufficient electrical current flow in the ferromagnetic conductor such that the ferromagnetic conductor resistively heats to a temperature of at least about 300.degree. C.

  20. Heating systems for heating subsurface formations

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Scott Vinh [Houston, TX; Vinegar, Harold J [Bellaire, TX

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  1. Subsurface temperatures and surface heat flow in the Michigan Basin and their relationships to regional subsurface fluid movement

    Science.gov (United States)

    Vugrinovich, R.

    1989-01-01

    Linear regression of 405 bottomhole temperature (BHT) measurements vs. associated depths from Michigan's Lower Peninsula results in the following equation relating BHT and depth: BHT(??C) = 14.5 + 0.0192 ?? depth(m) Temperature residuals, defined as (BHT measured)-(BHT calculated), were determined for each of the 405 BHT's. Areas of positive temperature residuals correspond to areas of regional groundwater discharge (determined from maps of equipotential surface) while areas of negative temperature residuals correspond to areas of regional groundwater recharge. These relationships are observed in the principal aquifers in rocks of Devonian and Ordovician age and in a portion of the principal aquifer in rocks of Silurian age. There is a similar correspondence between high surface heat flow (determined using the silica geothermometer) and regional groundwater discharge areas and low surface heat flow and regional groundwater recharge areas. Post-Jurassic depositional and tectonic histories suggest that the observed coupling of subsurface temperature and groundwater flow systems may have persisted since Jurassic time. Thus the higher subsurface palaeotemperatures (and palaeogeothermal gradients) indicated by recent studies most likely pre-date the Jurassic. ?? 1989.

  2. A locally conservative stabilized continuous Galerkin finite element method for two-phase flow in poroelastic subsurfaces

    Science.gov (United States)

    Deng, Q.; Ginting, V.; McCaskill, B.; Torsu, P.

    2017-10-01

    We study the application of a stabilized continuous Galerkin finite element method (CGFEM) in the simulation of multiphase flow in poroelastic subsurfaces. The system involves a nonlinear coupling between the fluid pressure, subsurface's deformation, and the fluid phase saturation, and as such, we represent this coupling through an iterative procedure. Spatial discretization of the poroelastic system employs the standard linear finite element in combination with a numerical diffusion term to maintain stability of the algebraic system. Furthermore, direct calculation of the normal velocities from pressure and deformation does not entail a locally conservative field. To alleviate this drawback, we propose an element based post-processing technique through which local conservation can be established. The performance of the method is validated through several examples illustrating the convergence of the method, the effectivity of the stabilization term, and the ability to achieve locally conservative normal velocities. Finally, the efficacy of the method is demonstrated through simulations of realistic multiphase flow in poroelastic subsurfaces.

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

    Science.gov (United States)

    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

  4. Electrical resistivity determination of subsurface layers, subsoil ...

    African Journals Online (AJOL)

    A geophysical investigation involving the electrical resistivity method was carried out at a site located in the eastern part of Akungba-Akoko, southwestern Nigeria. The aim of the investigation was to characterize the site according to subsurface lithologic layering, subsoil competence and soil corrosivity, which may affect the ...

  5. Linear Regression Models for Estimating True Subsurface ...

    Indian Academy of Sciences (India)

    47

    For the fact that subsurface resistivity is nonlinear, the datasets were first. 14 transformed into logarithmic scale to satisfy the basic regression assumptions. Three. 15 models, one each for the three array types, are thus developed based on simple linear. 16 relationships between the dependent and independent variables.

  6. Characterization of the Geology of Subsurface Shallow ...

    African Journals Online (AJOL)

    In the present study, the 2D electrical resistivity imaging of subsurface shallow conglomerate has been generated using through Computerized Resistivity Meter (CRM -500) and the Wenner electrode configuration has been used for 2D electrical resistivity imaging studies. The measured apparent resistivity values have ...

  7. Analysis and design of instrumented subsurface mooring

    Digital Repository Service at National Institute of Oceanography (India)

    SanilKumar, V.; Sakhardande, R.N.; Nayak, B.U.; Somanatha, G.S.

    be simplified. The objective of the present study is to design and analyse single point subsurface instrumented mooring system under a three dimensional current profile. A software 'SUBAM' is developed in FORTRAN-77 and it is applied to analyse a shallow water...

  8. Subsurface Environment Sampler for Improved In Situ Characterization of Subsurface Microbial Communities

    Science.gov (United States)

    Barnhart, E. P.; Ruppert, L. F.; Orem, W. H.; McIntosh, J. C.; Cunningham, A. B.; Fields, M. W.; Hiebert, R.; Hyatt, R.

    2016-12-01

    There is an increasing threat that deep aquifers, an important drinking water resource, may be contaminated by the extraction and transport of fossil fuels. This threat increases the need for improved groundwater monitoring and the ability to predict the extent to which microbial activity may remediate such contamination. The characterization of subsurface microbial communities could provide an ideal biomonitoring tool for the assessment of subsurface contamination due to prokaryotes environmental ubiquity, rapidity of response to environmental perturbation and the important role they play in hydrocarbon degradation and bioremediation. New DNA sequencing technologies provide the opportunity to cost-effectively identify the vast subsurface microbial ecosystem, but use of this new technology is restricted due to issues with sampling. Prior subsurface microbiology studies have relied on core samples that are expensive to obtain hard to collect aseptically and/or ground water samples that do not reflect in situ microbial densities or activities. The development of down-well incubation of sterile sediment with a Diffusive Microbial Sampler (DMS) has emerged as an alternative method to sample subsurface microbial communities that minimizes cost and contamination issues associated with traditional methods. We have designed a Subsurface Environment Sampler with a DMS module that could enable the anaerobic transport of the in situ microbial community from the field for laboratory bioremediation studies. This sampler could provide an inexpensive and standard method for subsurface microbial sampling which would make this tool useful for Federal, State, private and local agencies interested in monitoring contamination or the effectiveness of bioremediation activities in subsurface aquifers.

  9. Modelling of deep subsurface for geohazard risk assessment.

    NARCIS (Netherlands)

    Orlic, B.; Eijs, R. van

    2002-01-01

    Exploitation of subsurface natural resources, and subsurface storage of energy residues, may cause subsurface and surface deformation and damage to property. Deformation is generally difficult to assess and prove, although economical, environmental and societal interests are huge in terms of strain

  10. 4. Modelling Interconnectedness of Subsurface Flow Processes from ...

    African Journals Online (AJOL)

    User

    The study determined subsurface flow processes of 92.3 ha catchment area in order to examine functional relationship among ... subsurface flows, a combination of interflow and groundwater flow, had the two components contributing to stream flow on days ...... Modeling of Water Subsurface Lateral Movement on Top of a ...

  11. Three-phase heaters with common overburden sections for heating subsurface formations

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J [Bellaire, TX

    2012-02-14

    A heating system for a subsurface formation is described. The heating system includes three substantially u-shaped heaters with first end portions of the heaters being electrically coupled to a single, three-phase wye transformer and second end portions of the heaters being electrically coupled to each other and/or to ground. The three heaters may enter the formation through a first common wellbore and exit the formation through a second common wellbore so that the magnetic fields of the three heaters at least partially cancel out in the common wellbores.

  12. Microbial methanogenesis in subsurface oil and coal.

    Science.gov (United States)

    Meslé, Margaux; Dromart, Gilles; Oger, Philippe

    2013-11-01

    It is now clear that active methanogens are present in the deep-subsurface. This paper reviews microbial population structures and the biodegradation of organic compounds to methane in situ within oil reservoirs and coal deposits. It summarizes our current knowledge of methanogenes and methanogenesis, fermenters, synthrophs and microbial metabolism of complex organic compounds in these two widely occurring organic-rich subsurface environments. This review is not intended to be an exhaustive report of microbial diversity. Rather, it illustrates the similarities and differences between the two environments with specific examples, from the nature of the organic molecules to the methanogenic metabolic pathways and the structure of the microbial populations to demonstrate that widely diverging microbial populations show surprisingly similar metabolic capabilities. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  13. Directional Dipole Model for Subsurface Scattering

    DEFF Research Database (Denmark)

    Frisvad, Jeppe Revall; Hachisuka, Toshiya; Kjeldsen, Thomas Kim

    2014-01-01

    Rendering translucent materials using Monte Carlo ray tracing is computationally expensive due to a large number of subsurface scattering events. Faster approaches are based on analytical models derived from diffusion theory. While such analytical models are efficient, they miss out on some...... translucency effects in the rendered result. We present an improved analytical model for subsurface scattering that captures translucency effects present in the reference solutions but remaining absent with existing models. The key difference is that our model is based on ray source diffusion, rather than...... point source diffusion. A ray source corresponds better to the light that refracts through the surface of a translucent material. Using this ray source, we are able to take the direction of the incident light ray and the direction toward the point of emergence into account. We use a dipole construction...

  14. Subsurface materials management and containment system

    Science.gov (United States)

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2006-10-17

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  15. Radionuclide Sensors for Subsurface Water Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Timothy DeVol

    2006-06-30

    Contamination of the subsurface by radionuclides is a persistent and vexing problem for the Department of Energy. These radionuclides must be measured in field studies and monitoed in the long term when they cannot be removed. However, no radionuclide sensors existed for groundwater monitoring prior to this team's research under the EMSP program Detection of a and b decays from radionuclides in water is difficult due to their short ranges in condensed media.

  16. Metalliferous Biosignatures for Deep Subsurface Microbial Activity

    Science.gov (United States)

    Parnell, John; Brolly, Connor; Spinks, Sam; Bowden, Stephen

    2016-03-01

    The interaction of microbes and metals is widely assumed to have occurred in surface or very shallow subsurface environments. However new evidence suggests that much microbial activity occurs in the deep subsurface. Fluvial, lacustrine and aeolian `red beds' contain widespread centimetre-scale reduction spheroids in which a pale reduced spheroid in otherwise red rocks contains a metalliferous core. Most of the reduction of Fe (III) in sediments is caused by Fe (III) reducing bacteria. They have the potential to reduce a range of metals and metalloids, including V, Cu, Mo, U and Se, by substituting them for Fe (III) as electron acceptors, which are all elements common in reduction spheroids. The spheroidal morphology indicates that they were formed at depth, after compaction, which is consistent with a microbial formation. Given that the consequences of Fe (III) reduction have a visual expression, they are potential biosignatures during exploration of the terrestrial and extraterrestrial geological record. There is debate about the energy available from Fe (III) reduction on Mars, but the abundance of iron in Martian soils makes it one of the most valuable prospects for life there. Entrapment of the microbes themselves as fossils is possible, but a more realistic target during the exploration of Mars would be the colour contrasts reflecting selective reduction or oxidation. This can be achieved by analysing quartz grains across a reduction spheroid using Raman spectroscopy, which demonstrates its suitability for life detection in subsurface environments. Microbial action is the most suitable explanation for the formation of reduction spheroids and may act as metalliferous biosignatures for deep subsurface microbial activity.

  17. Metalliferous Biosignatures for Deep Subsurface Microbial Activity.

    Science.gov (United States)

    Parnell, John; Brolly, Connor; Spinks, Sam; Bowden, Stephen

    2016-03-01

    The interaction of microbes and metals is widely assumed to have occurred in surface or very shallow subsurface environments. However new evidence suggests that much microbial activity occurs in the deep subsurface. Fluvial, lacustrine and aeolian 'red beds' contain widespread centimetre-scale reduction spheroids in which a pale reduced spheroid in otherwise red rocks contains a metalliferous core. Most of the reduction of Fe (III) in sediments is caused by Fe (III) reducing bacteria. They have the potential to reduce a range of metals and metalloids, including V, Cu, Mo, U and Se, by substituting them for Fe (III) as electron acceptors, which are all elements common in reduction spheroids. The spheroidal morphology indicates that they were formed at depth, after compaction, which is consistent with a microbial formation. Given that the consequences of Fe (III) reduction have a visual expression, they are potential biosignatures during exploration of the terrestrial and extraterrestrial geological record. There is debate about the energy available from Fe (III) reduction on Mars, but the abundance of iron in Martian soils makes it one of the most valuable prospects for life there. Entrapment of the microbes themselves as fossils is possible, but a more realistic target during the exploration of Mars would be the colour contrasts reflecting selective reduction or oxidation. This can be achieved by analysing quartz grains across a reduction spheroid using Raman spectroscopy, which demonstrates its suitability for life detection in subsurface environments. Microbial action is the most suitable explanation for the formation of reduction spheroids and may act as metalliferous biosignatures for deep subsurface microbial activity.

  18. Cultivation Of Deep Subsurface Microbial Communities

    Science.gov (United States)

    Obrzut, Natalia; Casar, Caitlin; Osburn, Magdalena R.

    2018-01-01

    The potential habitability of surface environments on other planets in our solar system is limited by exposure to extreme radiation and desiccation. In contrast, subsurface environments may offer protection from these stressors and are potential reservoirs for liquid water and energy that support microbial life (Michalski et al., 2013) and are thus of interest to the astrobiology community. The samples used in this project were extracted from the Deep Mine Microbial Observatory (DeMMO) in the former Homestake Mine at depths of 800 to 2000 feet underground (Osburn et al., 2014). Phylogenetic data from these sites indicates the lack of cultured representatives within the community. We used geochemical data to guide media design to cultivate and isolate organisms from the DeMMO communities. Media used for cultivation varied from heterotrophic with oxygen, nitrate or sulfate to autotrophic media with ammonia or ferrous iron. Environmental fluid was used as inoculum in batch cultivation and strains were isolated via serial transfers or dilution to extinction. These methods resulted in isolating aerobic heterotrophs, nitrate reducers, sulfate reducers, ammonia oxidizers, and ferric iron reducers. DNA sequencing of these strains is underway to confirm which species they belong to. This project is part of the NASA Astrobiology Institute Life Underground initiative to detect and characterize subsurface microbial life; by characterizing the intraterrestrials, the life living deep within Earth’s crust, we aim to understand the controls on how and where life survives in subsurface settings. Cultivation of terrestrial deep subsurface microbes will provide insight into the survival mechanisms of intraterrestrials guiding the search for these life forms on other planets.

  19. Drill Embedded Nanosensors For Planetary Subsurface Exploration

    Science.gov (United States)

    Li, Jing

    2014-01-01

    We have developed a carbon nanotube (CNT) sensor for water vapor detection under Martian Conditions and the miniaturized electronics can be embedded in the drill bit for collecting sensor data and transmit it to a computer wirelessly.This capability will enable the real time measurement of ice during drilling. With this real time and in-situ measurement, subsurface ice detection can be easy, fast, precise and low cost.

  20. Hydrogen utilization potential in subsurface sediments

    Directory of Open Access Journals (Sweden)

    Rishi Ram Adhikari

    2016-01-01

    Full Text Available Subsurface microbial communities undertake many terminal electron-accepting processes, often simultaneously. Using a tritium-based assay, we measured the potential hydrogen oxidation catalyzed by hydrogenase enzymes in several subsurface sedimentary environments (Lake Van, Barents Sea, Equatorial Pacific and Gulf of Mexico with different predominant electron-acceptors. Hydrogenases constitute a diverse family of enzymes expressed by microorganisms that utilize molecular hydrogen as a metabolic substrate, product or intermediate. The assay reveals the potential for utilizing molecular hydrogen and allows qualitative detection of microbial activity irrespective of the predominant electron-accepting process. Because the method only requires samples frozen immediately after recovery, the assay can be used for identifying microbial activity in subsurface ecosystems without the need to preserve live material.We measured potential hydrogen oxidation rates in all samples from multiple depths at several sites that collectively span a wide range of environmental conditions and biogeochemical zones. Potential activity normalized to total cell abundance ranges over five orders of magnitude and varies, dependent upon the predominant terminal electron acceptor. Lowest per-cell potential rates characterize the zone of nitrate reduction and highest per-cell potential rates occur in the methanogenic zone. Possible reasons for this relationship to predominant electron acceptor include (i increasing importance of fermentation in successively deeper biogeochemical zones and (ii adaptation of H2ases to successively higher concentrations of H2 in successively deeper zones.

  1. Hydrogen Utilization Potential in Subsurface Sediments.

    Science.gov (United States)

    Adhikari, Rishi R; Glombitza, Clemens; Nickel, Julia C; Anderson, Chloe H; Dunlea, Ann G; Spivack, Arthur J; Murray, Richard W; D'Hondt, Steven; Kallmeyer, Jens

    2016-01-01

    Subsurface microbial communities undertake many terminal electron-accepting processes, often simultaneously. Using a tritium-based assay, we measured the potential hydrogen oxidation catalyzed by hydrogenase enzymes in several subsurface sedimentary environments (Lake Van, Barents Sea, Equatorial Pacific, and Gulf of Mexico) with different predominant electron-acceptors. Hydrogenases constitute a diverse family of enzymes expressed by microorganisms that utilize molecular hydrogen as a metabolic substrate, product, or intermediate. The assay reveals the potential for utilizing molecular hydrogen and allows qualitative detection of microbial activity irrespective of the predominant electron-accepting process. Because the method only requires samples frozen immediately after recovery, the assay can be used for identifying microbial activity in subsurface ecosystems without the need to preserve live material. We measured potential hydrogen oxidation rates in all samples from multiple depths at several sites that collectively span a wide range of environmental conditions and biogeochemical zones. Potential activity normalized to total cell abundance ranges over five orders of magnitude and varies, dependent upon the predominant terminal electron acceptor. Lowest per-cell potential rates characterize the zone of nitrate reduction and highest per-cell potential rates occur in the methanogenic zone. Possible reasons for this relationship to predominant electron acceptor include (i) increasing importance of fermentation in successively deeper biogeochemical zones and (ii) adaptation of H2ases to successively higher concentrations of H2 in successively deeper zones.

  2. Monitoring Subsurface Objects Using Resonant Seismic Emission

    Science.gov (United States)

    Konstantinov, V.; Korneev, V.

    2008-12-01

    The numerical modeling results and field data indicate that some contrast subsurface objects (such as tunnels, caves, pipes, filled pits, and fluid-filled fractures) are capable to trap seismic energy and generate durable resonant oscillations. These oscillations are comprised of surface types of circumferential waves which multiply rotate around the object. Resonant emission of such trapped energy occurs primarily in form of shear body waves that can be detected by remotely placed receivers. Resonant emission reveals itself in form of sharp resonant peaks for the late parts of the records, when all strong direct and primary reflected waves are gone. These peaks are observed in the field data for a buried barrel filled with water, in 2D finite- difference modeling results and in exact canonical solution for a fluid-filled sphere. Computed movie for diffraction of a plane wave upon low-velocity elastic sphere confirms generation of resonances by durable surface waves. We show that resonant emission has characteristic quasi-hyperbolic travel-time patterns on shot-gathers. Inversion of these patterns can be performed in frequency domain after muting strong direct and primary scattered waves. Subsurface objects can be detected and imaged at a single resonance frequency without an accurate knowledge about source trigger time. Imaging of subsurface objects requires information about shear velocity distribution in an embedding medium, which can be done interactively during inversion. Resonant emission data processing is done using KinetiK Professional visualization and processing software.

  3. Subsurface Examination of a Foliar Biofilm Using Scanning Electron- and Focused-Ion-Beam Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, Patricia K.; Arey, Bruce W.; Mahaffee, Walt F.

    2011-08-01

    The dual beam scanning electron microscope, equipped with both a focused ion- and scanning electron- beam (FIB SEM) is a novel tool for the exploration of the subsurface structure of biological tissues. The FIB can remove a predetermined amount of material from a selected site to allow for subsurface exploration and when coupled with SEM or scanning ion- beam microscopy (SIM) could be suitable to examine the subsurface structure of bacterial biofilms on the leaf surface. The suitability of chemical and cryofixation was examined for use with the FIB SEM to examine bacterial biofilms on leaf surfaces. The biological control agent, Burkholderia pyroccinia FP62, that rapidly colonizes the leaf surface and forms biofilms, was inoculated onto geranium leaves and incubated in a greenhouse for 7 or 14 days. Cryofixation was not suitable for examination of leaf biofilms because it created a frozen layer over the leaf surface that cracked when exposed to the electron beam and the protective cap required for FIB milling could not be accurately deposited. With chemically fixed samples, it was possible to precisely FIB mill a single cross section (5 µm) or sequential cross sections from a single site without any damage to the surrounding surface. Biofilms, 7 days post-inoculation (DPI), were composed of 2 to 5 bacterial cell layers while biofilms 14 DPI ranged from 5 to greater than 30 cell layers. Empty spaces between bacteria cells in the subsurface structure were observed in biofilms 7- and 14-DPI. Sequential cross sections inferred that the empty spaces were often continuous between FP62 cells and could possibly make up a network of channels throughout the biofilm. FIB SEM was a useful tool to observe the subsurface composition of a foliar biofilm.

  4. Using Muons to Image the Subsurface.

    Energy Technology Data Exchange (ETDEWEB)

    Bonal, Nedra [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cashion, Avery Ted [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cieslewski, Grzegorz [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dorsey, Daniel J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Foris, Adam [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Miller, Timothy J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roberts, Barry L [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Su, Jiann-Cherng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dreesen, Wendi [NSTec, Livermore, CA (United States); Green, J. Andrew [NSTec, Livermore, CA (United States); Schwellenbach, David [NSTec, Livermore, CA (United States)

    2016-11-01

    Muons are subatomic particles that can penetrate the earth 's crust several kilometers and may be useful for subsurface characterization . The absorption rate of muons depends on the density of the materials through which they pass. Muons are more sensitive to density variation than other phenomena, including gravity, making them beneficial for subsurface investigation . Measurements of muon flux rate at differing directions provide density variations of the materials between the muon source (cosmic rays and neutrino interactions) and the detector, much like a CAT scan. Currently, muon tomography can resolve features to the sub-meter scale. This work consists of three parts to address the use of muons for subsurface characterization : 1) assess the use of muon scattering for estimating density differences of common rock types, 2 ) using muon flux to detect a void in rock, 3) measure muon direction by designing a new detector. Results from this project lay the groundwork for future directions in this field. Low-density objects can be detected by muons even when enclosed in high-density material like lead, and even small changes in density (e.g. changes due to fracturing of material) can be detected. Rock density has a linear relationship with muon scattering density per rock volume when this ratio is greater than 0.10 . Limitations on using muon scattering to assess density changes among common rock types have been identified. However, other analysis methods may show improved results for these relatively low density materials. Simulations show that muons can be used to image void space (e.g. tunnels) within rock but experimental results have been ambiguous. Improvements are suggested to improve imaging voids such as tunnels through rocks. Finally, a muon detector has been designed and tested to measure muon direction, which will improve signal-to-noise ratio and help address fundamental questions about the source of upgoing muons .

  5. Noble gas fractionation during subsurface gas migration

    Science.gov (United States)

    Sathaye, Kiran J.; Larson, Toti E.; Hesse, Marc A.

    2016-09-01

    Environmental monitoring of shale gas production and geological carbon dioxide (CO2) storage requires identification of subsurface gas sources. Noble gases provide a powerful tool to distinguish different sources if the modifications of the gas composition during transport can be accounted for. Despite the recognition of compositional changes due to gas migration in the subsurface, the interpretation of geochemical data relies largely on zero-dimensional mixing and fractionation models. Here we present two-phase flow column experiments that demonstrate these changes. Water containing a dissolved noble gas is displaced by gas comprised of CO2 and argon. We observe a characteristic pattern of initial co-enrichment of noble gases from both phases in banks at the gas front, followed by a depletion of the dissolved noble gas. The enrichment of the co-injected noble gas is due to the dissolution of the more soluble major gas component, while the enrichment of the dissolved noble gas is due to stripping from the groundwater. These processes amount to chromatographic separations that occur during two-phase flow and can be predicted by the theory of gas injection. This theory provides a mechanistic basis for noble gas fractionation during gas migration and improves our ability to identify subsurface gas sources after post-genetic modification. Finally, we show that compositional changes due to two-phase flow can qualitatively explain the spatial compositional trends observed within the Bravo Dome natural CO2 reservoir and some regional compositional trends observed in drinking water wells overlying the Marcellus and Barnett shale regions. In both cases, only the migration of a gas with constant source composition is required, rather than multi-stage mixing and fractionation models previously proposed.

  6. Subsurface warming across the Veluwe area (Netherlands) driven by climate change, urbanisation, groundwater abstraction and aquifer energy storage

    Science.gov (United States)

    Bense, Victor; de Kleijn, Christian; van Daal, Jonathan

    2017-04-01

    Atmospheric warming, urbanisation, land-use changes, groundwater abstraction and aquifer thermal energy storage can induce significant changes in the subsurface thermal regime. These need to better understood and monitored in order for humanity to make efficient use of the subsurface as a thermal reservoir, but also to understand how this space acts as a heat sink during the current warming of the climate. This work aims to improve our understanding of the relative importance, spatiotemporal characteristics and mechanisms of how various environmental processes and anthropogenic activities control changes in subsurface thermal regimes. Such changes are poignantly illustrated by temperature-depth profiles recently obtained in 30 boreholes upto several hundreds of meters deep that are present in the unconsolidated sedimentary aquifer system of the Veluwe area, Netherlands. A comparison to similar data collected in 1978-1980 shows that since then across the entire study area subsurface warming has occurred to depths upto 250 m. The availability of historic land-use maps, hydrogeological and meteorological data for this area allow for a detailed analysis of the observed subsurface warming patterns, which is aided by numerical models of coupled groundwater and heat flow. On a regional scale and across the entire first 100-150 m into the subsurface, the classic thermal signatures of variations in land-use, groundwater recharge and discharge fluxes, are increasingly overprinted by those of regional atmospheric warming and urbanisation. In the topographically higher, forested groundwater recharge areas groundwater is significantly cooler (upto 6 K) than in the open agricultural lands where groundwater is discharging. The presence of a thick (upto 30-40 m) unsaturated zone in the recharge area probably enhances this striking contrast in groundwater temperature in addition to the effects of groundwater recharge and the presence of forest. Locally and at larger depths, however

  7. Geophysical data fusion for subsurface imaging

    Science.gov (United States)

    Hoekstra, P.; Vandergraft, J.; Blohm, M.; Porter, D.

    1993-08-01

    A geophysical data fusion methodology is under development to combine data from complementary geophysical sensors and incorporate geophysical understanding to obtain three dimensional images of the subsurface. The research reported here is the first phase of a three phase project. The project focuses on the characterization of thin clay lenses (aquitards) in a highly stratified sand and clay coastal geology to depths of up to 300 feet. The sensor suite used in this work includes time-domain electromagnetic induction (TDEM) and near surface seismic techniques. During this first phase of the project, enhancements to the acquisition and processing of TDEM data were studied, by use of simulated data, to assess improvements for the detection of thin clay layers. Secondly, studies were made of the use of compressional wave and shear wave seismic reflection data by using state-of-the-art high frequency vibrator technology. Finally, a newly developed processing technique, called 'data fusion' was implemented to process the geophysical data, and to incorporate a mathematical model of the subsurface strata. Examples are given of the results when applied to real seismic data collected at Hanford, WA, and for simulated data based on the geology of the Savannah River Site.

  8. Method and apparatus for subsurface exploration

    Science.gov (United States)

    Wilcox, Brian (Inventor)

    2002-01-01

    A subsurface explorer (SSX) for exploring beneath the terrestrial surface of planetary bodies such as the Earth, Mars, or comets. This exploration activity utilizes appropriate sensors and instrument to evaluate the composition, structure, mineralogy and possibly biology of the subsurface medium, as well as perhaps the ability to return samples of that medium back to the surface. The vehicle comprises an elongated skin or body having a front end and a rear end, with a nose piece at the front end for imparting force to composition material of the planetary body. Force is provided by a hammer mechanism to the back side of a nose piece from within the body of the vehicle. In the preferred embodiment, a motor spins an intermediate shaft having two non-uniform threads along with a hammer which engages these threads with two conical rollers. A brake assembly halts the rotation of the intermediate shaft, causing the conical roller to spin down the non-uniform thread to rapidly and efficiently convert the rotational kinetic energy of the hammer into translational energy.

  9. Atmospheric energy for subsurface life on Mars?

    Science.gov (United States)

    Weiss, B. P.; Yung, Y. L.; Nealson, K. H.

    2000-01-01

    The location and density of biologically useful energy sources on Mars will limit the biomass, spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmospheric H(2) and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H(2) and CO is limited in the top few hundred meters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth, it is 2,000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochemical energy flux can only penetrate to 100- to 1,000-m depth, where most H(2)O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life.

  10. Geochemical Sensors of Fracturing in the Subsurface

    Science.gov (United States)

    Krogstad, E. J.; Burghardt, J. A.; Shen, S.; Wellsandt, T. C.; Brown, C. F.

    2016-12-01

    Although advancements have been made in the use of tracers for subsurface interrogation, there continue to be issues correlating results from laboratory experiments to field tests involving the analysis of tracers in flow back fluids. One of the largest confounding factors is due to the heterogeneity of the natural system vs. the materials used in bench-scale tests. Many laboratory tests use field-relevant materials; however, the samples are typically processed (i.e., crushed) such that they no longer represent the physical whole rock configuration of the reservoir. To avoid this shortcoming, we used specialized high pressure/temperature test equipment to quantitatively measure the development, surface area, and interconnectivity of hydraulically induced fractures on whole rock cores. The application involves the use of novel element-pair tracers (consisting of a suite of rare earth elements [REE]) to elucidate the total surface of the fractured system. Initial results indicate that interaction of the tracer with multiple rock types produces a significant depletion in select REE, largely as a function of surface area of the rock, and less as a function of the time of interaction. Three-dimensional X-ray microtomography is being used to validate surface area estimates derived via analysis of the chemical tracers. This talk will demonstrate how this novel sensor approach affords a simple, low-cost alternative for subsurface interrogation of fracture development.

  11. Method of imaging the electrical conductivity distribution of a subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Timothy C.

    2017-09-26

    A method of imaging electrical conductivity distribution of a subsurface containing metallic structures with known locations and dimensions is disclosed. Current is injected into the subsurface to measure electrical potentials using multiple sets of electrodes, thus generating electrical resistivity tomography measurements. A numeric code is applied to simulate the measured potentials in the presence of the metallic structures. An inversion code is applied that utilizes the electrical resistivity tomography measurements and the simulated measured potentials to image the subsurface electrical conductivity distribution and remove effects of the subsurface metallic structures with known locations and dimensions.

  12. Microbial communities in the deep subsurface

    Science.gov (United States)

    Krumholz, Lee R.

    The diversity of microbial populations and microbial communities within the earth's subsurface is summarized in this review. Scientists are currently exploring the subsurface and addressing questions of microbial diversity, the interactions among microorganisms, and mechanisms for maintenance of subsurface microbial communities. Heterotrophic anaerobic microbial communities exist in relatively permeable sandstone or sandy sediments, located adjacent to organic-rich deposits. These microorganisms appear to be maintained by the consumption of organic compounds derived from adjacent deposits. Sources of organic material serving as electron donors include lignite-rich Eocene sediments beneath the Texas coastal plain, organic-rich Cretaceous shales from the southwestern US, as well as Cretaceous clays containing organic materials and fermentative bacteria from the Atlantic Coastal Plain. Additionally, highly diverse microbial communities occur in regions where a source of organic matter is not apparent but where igneous rock is present. Examples include the basalt-rich subsurface of the Columbia River valley and the granitic subsurface regions of Sweden and Canada. These subsurface microbial communities appear to be maintained by the action of lithotrophic bacteria growing on H2 that is chemically generated within the subsurface. Other deep-dwelling microbial communities exist within the deep sediments of oceans. These systems often rely on anaerobic metabolism and sulfate reduction. Microbial colonization extends to the depths below which high temperatures limit the ability of microbes to survive. Energy sources for the organisms living in the oceanic subsurface may originate as oceanic sedimentary deposits. In this review, each of these microbial communities is discussed in detail with specific reference to their energy sources, their observed growth patterns, and their diverse composition. This information is critical to develop further understanding of subsurface

  13. Drilling subsurface wellbores with cutting structures

    Science.gov (United States)

    Mansure, Arthur James; Guimerans, Rosalvina Ramona

    2010-11-30

    A system for forming a wellbore includes a drill tubular. A drill bit is coupled to the drill tubular. One or more cutting structures are coupled to the drill tubular above the drill bit. The cutting structures remove at least a portion of formation that extends into the wellbore formed by the drill bit.

  14. The DOE Subsurface (SubTER) Initiative: Revolutionizing Responsible use of the Subsurface for Energy Production and Storage

    Science.gov (United States)

    Hubbard, S. S.; Walck, M. C.; Blankenship, D.; Bonneville, A.; Bromhal, G. S.; Daley, T. M.; Pawar, R.; Polsky, Y.; Mattson, E.; Mellors, R. J.

    2015-12-01

    The subsurface supplies more than 80% of the U.S.'s total energy needs through geothermal and hydrocarbon strategies and also provides vast potential for safe storage of CO2 and disposal of nuclear waste. Responsible and efficient use of the subsurface poses many challenges, many of which require the capability to monitor and manipulate sub-surface stress, fractures, and fluid flow at all scales. Adaptive control of subsurface fractures and flow is a multi-disciplinary challenge that, if achieved, has the potential to transform all subsurface energy strategies. As part of the U.S. Department of Energy's SubTER (Subsurface Technology and Engineering Research development and demonstration) initiative, a multi-National Laboratory team is developing next-generation approaches that will allow for adaptive control of subsurface fractures and flow. SubTER has identified an initial suite of technical thrust areas to focus work, and has initiated a number of small projects. This presentation will describe early progress associated with the SubTER technical topic areas of wellbore integrity, subsurface stress and induced seismicity, permeability manipulation and new subsurface signals. It will also describe SubTER plans, and provide a venue to solicit suggestions and discuss potential partnerships associated with future research directions.

  15. ASSESSMENT OF THE SUBSURFACE FATE OF MONOETHANOLAMINE

    Energy Technology Data Exchange (ETDEWEB)

    James A. Sorensen; John R. Gallagher; Lori G. Kays

    2000-05-01

    Burial of amine reclaimer unit sludges and system filters has resulted in contamination of soil at the CanOxy Okotoks decommissioned sour gas-processing plant with amines, amine byproducts, and salts. A three-phase research program was devised to investigate the natural attenuation process that controls the subsurface transport and fate of these contaminants and to apply the results toward the development of a strategy for the remediation of this type of contamination in soils. Phase I experimental activities examined interactions between monoethanolamine (MEA) and sediment, the biodegradability of MEA in soils at various concentrations and temperatures, and the biodegradability of MEA sludge contamination in a soil slurry bioreactor. The transport and fate of MEA in the subsurface was found to be highly dependant on the nature of the release, particularly MEA concentration and conditions of the subsurface environment, i.e., pH, temperature, and oxygen availability. Pure compound biodegradation experiments in soil demonstrated rapid biodegradation of MEA under aerobic conditions and moderate temperatures (>6 C). Phase II landfarming activities confirmed that these contaminants are readily biodegradable in soil under ideal laboratory conditions, yet considerable toxicity was observed in the remaining material. Examination of water extracts from the treated soil suggested that the toxicity is water-soluble. Phase II activities led to the conclusion that landfarming is not the most desirable bioremediation technique; however, an engineered biopile with a leachate collection system could remove the remaining toxic fraction from the soil. Phase III was initiated to conduct field-based experimental activities to examine the optimized remediation technology. A pilot-scale engineered biopile was constructed at a decommissioned gas-sweetening facility in Okotoks, Alberta, Canada. On the basis of a review of the analytical and performance data generated from soil and

  16. Subsurface data visualization in Virtual Reality

    Science.gov (United States)

    Krijnen, Robbert; Smelik, Ruben; Appleton, Rick; van Maanen, Peter-Paul

    2017-04-01

    Due to their increasing complexity and size, visualization of geological data is becoming more and more important. It enables detailed examining and reviewing of large volumes of geological data and it is often used as a communication tool for reporting and education to demonstrate the importance of the geology to policy makers. In the Netherlands two types of nation-wide geological models are available: 1) Layer-based models in which the subsurface is represented by a series of tops and bases of geological or hydrogeological units, and 2) Voxel models in which the subsurface is subdivided in a regular grid of voxels that can contain different properties per voxel. The Geological Survey of the Netherlands (GSN) provides an interactive web portal that delivers maps and vertical cross-sections of such layer-based and voxel models. From this portal you can download a 3D subsurface viewer that can visualize the voxel model data of an area of 20 × 25 km with 100 × 100 × 5 meter voxel resolution on a desktop computer. Virtual Reality (VR) technology enables us to enhance the visualization of this volumetric data in a more natural way as compared to a standard desktop, keyboard mouse setup. The use of VR for data visualization is not new but recent developments has made expensive hardware and complex setups unnecessary. The availability of consumer of-the-shelf VR hardware enabled us to create an new intuitive and low visualization tool. A VR viewer has been implemented using the HTC Vive head set and allows visualization and analysis of the GSN voxel model data with geological or hydrogeological units. The user can navigate freely around the voxel data (20 × 25 km) which is presented in a virtual room at a scale of 2 × 2 or 3 × 3 meters. To enable analysis, e.g. hydraulic conductivity, the user can select filters to remove specific hydrogeological units. The user can also use slicing to cut-off specific sections of the voxel data to get a closer look. This slicing

  17. Detection of microbial Life in the Subsurface

    Science.gov (United States)

    Stan-Lotter, H.; Fendrihan, S.; Dornmayr-Pfaffenhuemer, M.; Legat, A.; Gruber, C.; Weidler, G.; Gerbl, F.

    2007-08-01

    In recent years microbial communities were detected, which dwell in rocks, soil and caves deep below the surface of the Earth. This has led to a new view of the diversity of the terrestrial biosphere and of the physico-chemical boundaries for life. Two types of subterranean environments are Permo-Triassic salt sediments and thermal radioactive springs from igneous rocks in the Alps. Viable extremely halophilic archaea were isolated from ancient salt sediments which are estimated to be about 250 million years old (1). Chemotaxonomic and molecular characterization showed that they represent novel species, e. g. Halococcus salifodinae, Hcc. dombrowskiiand Halobacterium noricense. Simulation experiments with artificial halite suggested that these microorganisms probably survived while embedded in fluid inclusions. In the thermal springs, evidence for numerous novel microorganisms was found by 16S rDNA sequencing and probing for some metabolic genes; in addition, scanning electron microscopy of biofilms on the rock surfaces revealed great diversity of morphotypes (2). These communities appear to be active and growing, although their energy and carbon sources are entirely unknown. The characterization of subsurface inhabitants is of astrobiological relevance since extraterrestrial halite has been detected (3) and since microbial life on Mars, if existent, may have retreated into the subsurface. As a long-term goal, a thorough census of terrestrial microorganisms should be taken and their survival potential be determined in view of future missions for the search for extraterrestrial life, including planning precautions against possible forward contamination by space probes. (1) Fendrihan, S., Legat, A., Gruber, C., Pfaffenhuemer, M., Weidler, G., Gerbl, F., Stan-Lotter, H. (2006) Extremely halophilic archaea and the issue of long term microbial survival. Reviews in Environmental Science and Bio/technology 5, 1569-1605. (2) Weidler, G.W., Dornmayr-Pfaffenhuemer, M., Gerbl

  18. Entrepreneurial Couples

    DEFF Research Database (Denmark)

    Dahl, Michael S.; Van Praag, Mirjam; Thompson, Peter

    2015-01-01

    We study possible motivations for co-entreprenurial couples to start up a joint firm, using a sample of 1,069 Danish couples that established a joint enterprise between 2001 and 2010. We compare their pre-entry characteristics, firm performance and post-dissolution private and financial outcomes...... with a selected set of comparable firms and couples. We find evidence that couples often establish a business together because one spouse – most commonly the female – has limited outside opportunities in the labor market. However, the financial benefits for each of the spouses, and especially the female...

  19. Complex Systems Science for Subsurface Fate and Transport Report from the August 2009 Workshop

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-03-01

    The subsurface environment, which encompasses the vadose and saturated zones, is a heterogeneous, geologically complex domain. Believed to contain a large percentage of Earth's biomass in the form of microorganisms, the subsurface is a dynamic zone where important biogeochemical cycles work to sustain life. Actively linked to the atmosphere and biosphere through the hydrologic and carbon cycles, the subsurface serves as a storage location for much of Earth's fresh water. Coupled hydrological, microbiological, and geochemical processes occurring within the subsurface environment cause the local and regional natural chemical fluxes that govern water quality. These processes play a vital role in the formation of soil, economically important fossil fuels, mineral deposits, and other natural resources. Cleaning up Department of Energy (DOE) lands impacted by legacy wastes and using the subsurface for carbon sequestration or nuclear waste isolation require a firm understanding of these processes and the documented means to characterize the vertical and spatial distribution of subsurface properties directing water, nutrient, and contaminant flows. This information, along with credible, predictive models that integrate hydrological, microbiological, and geochemical knowledge over a range of scales, is needed to forecast the sustainability of subsurface water systems and to devise ways to manage and manipulate dynamic in situ processes for beneficial outcomes. Predictive models provide the context for knowledge integration. They are the primary tools for forecasting the evolving geochemistry or microbial ecology of groundwater under various scenarios and for assessing and optimizing the potential effectiveness of proposed approaches to carbon sequestration, waste isolation, or environmental remediation. An iterative approach of modeling and experimentation can reveal powerful insights into the behavior of subsurface systems. State-of-science understanding codified

  20. Repository Subsurface Preliminary Fire Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Richard C. Logan

    2001-07-30

    This fire hazard analysis identifies preliminary design and operations features, fire, and explosion hazards, and provides a reasonable basis to establish the design requirements of fire protection systems during development and emplacement phases of the subsurface repository. This document follows the Technical Work Plan (TWP) (CRWMS M&O 2001c) which was prepared in accordance with AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities''; Attachment 4 of AP-ESH-008, ''Hazards Analysis System''; and AP-3.11Q, ''Technical Reports''. The objective of this report is to establish the requirements that provide for facility nuclear safety and a proper level of personnel safety and property protection from the effects of fire and the adverse effects of fire-extinguishing agents.

  1. Acclimation of subsurface microbial communities to mercury

    DEFF Research Database (Denmark)

    de Lipthay, Julia R.; Rasmussen, Lasse Dam; Oregaard, Gunnar

    2008-01-01

    We studied the acclimation to mercury of bacterial communities of different depths from contaminated and noncontaminated floodplain soils. The level of mercury tolerance of the bacterial communities from the contaminated site was higher than those of the reference site. Furthermore, the level...... of mercury tolerance and functional versatility of bacterial communities in contaminated soils initially were higher for surface soil, compared with the deeper soils. However, following new mercury exposure, no differences between bacterial communities were observed, which indicates a high adaptive potential...... of the subsurface communities, possibly due to differences in the availability of mercury. IncP-1 trfA genes were detected in extracted community DNA from all soil depths of the contaminated site, and this finding was correlated to the isolation of four different mercury-resistance plasmids, all belonging...

  2. Air-water flow in subsurface systems

    Science.gov (United States)

    Hansen, A.; Mishra, P.

    2013-12-01

    Groundwater traces its roots to tackle challenges of safe and reliable drinking water and food production. When the groundwater level rises, air pressure in the unsaturated Vadose zone increases, forcing air to escape from the ground surface. Abnormally high and low subsurface air pressure can be generated when the groundwater system, rainfall, and sea level fluctuation are favorably combined [Jiao and Li, 2004]. Through this process, contamination in the form of volatile gases may diffuse from the ground surface into residential areas, or possibly move into groundwater from industrial waste sites. It is therefore crucial to understand the combined effects of air-water flow in groundwater system. Here we investigate theoretically and experimentally the effects of air and water flow in groundwater system.

  3. Gravimetric examination of Hagia Sophia's subsurface structure

    Science.gov (United States)

    Friedrich, Jürgen; Gerstenecker, Carl; Gürkan, Onur

    1996-10-01

    The subsurface structure of Hagia Sophia, one of the oldest sacred monuments in the world built between 532 537 under the reign of Justinian in today's Istanbul, has been investigated by using two relative LaCoste-Romberg gravimeters in order to detect hidden cavities which have also served as earthquake dampers in similar constructions. On the building's ground floor a grid of 100 points with a grid size of about 4.m was measured. The mean gravimetric point error was ± 3.10-8 ms-2. The result of the examination is that cavities were not detected in the inner central part of Hagia Sophia with a larger diameter than 8.m down to a depth of about 20.m, and Hagia Sophia's foundation was found to be a slope of natural rock with a downward inclination to the East that has a small crest symmetrical to the building's East-West axis.

  4. Novel Archaea and Bacteria in a hydrologically isolated deep subsurface environment

    Science.gov (United States)

    Chandler, Darrell P.; Brockman, Fred J.; Fredrickson, James K.

    1997-07-01

    Total community DNA and RNA were extracted from a deep (188 m), saturated, mesophilic (17 degree(s)C), low biomass (10(superscript 4) cells g(superscript -1)) subsurface paleosol. 16S rDNA was amplified by PCR using universal eubacterial or archaeal primers and cloned. Cloned 16S rDNA fragments were sequenced and subjected to phylogenetic analysis. A novel clade of Crenarchaea were discovered which are most closely related to a single clone recovered from an Fe-S hot spring (80 degree(s)C). Novel Bacterial sequences were also found which branch deeply in the universal phylogenetic tree in association with Chloroflexus, Deinococcus, and Thermus. Total RNA analysis suggested that the novel Crenarchaea were active in this environment. Geological and hydrologic properties of the sediment indicate that microbial and nutrient transport between individual strata are restricted, and are consistent with chemolithoautotrophic metabolisms of cultured Crenarchaea involving the H(subscript 2)/SO(subscript 4) electron donor/acceptor couple. The physical properties of the surrounding lithologies suggest that these novel microorganisms are descendants of the microbial communities originally deposited with the sediment ca. 6 - 8 Mya. Identification of these novel, active microorganisms in an oligotrophic, hydrologically isolated subsurface system provides an opportunity and species-specific nucleic acid sequences and probes necessary to study long-term microbial survival in terrestrial subsurface environments.

  5. 10 CFR 39.45 - Subsurface tracer studies.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Subsurface tracer studies. 39.45 Section 39.45 Energy....45 Subsurface tracer studies. (a) The licensee shall require all personnel handling radioactive tracer material to use protective gloves and, if required by the license, other protective clothing and...

  6. Subsurface melting of nylon by friction-induced vibrations

    NARCIS (Netherlands)

    Vroegop, P.H.; Bosma, R.

    1985-01-01

    Dry sliding of nylon on steel may lead to subsurface recrystallization of the polymer. This phenomenon is described and explained by subsurface melting due to internal heating as a result of the dissipation of frictioninduced vibrations at frequencies above 10 kHz. A vibration model relating the

  7. Modelling Interconnectedness of Subsurface Flow Processes from a ...

    African Journals Online (AJOL)

    The study determined subsurface flow processes of 92.3 ha catchment area in order to examine functional relationship among the surface and subsurface flow variables from the water balance components data. Days without rainfall had zero infiltration while peak values of infiltrated water corresponded with peak rainfall.

  8. Geochemical characterization of subsurface sediments in the Netherlands

    NARCIS (Netherlands)

    Huisman, D.J.

    1998-01-01

    Traditionally, the Netherlands' subsurface is mainly used to obtain good quality drinking and industrial waters from the different aquifers. Due to the lack of space on the surface, increasing environmental problems and demand for energy, the subsurface will be used increasingly for other

  9. 75 FR 1276 - Requirements for Subsurface Safety Valve Equipment

    Science.gov (United States)

    2010-01-11

    ... Minerals Management Service 30 CFR Part 250 RIN 1010-AD45 Requirements for Subsurface Safety Valve Equipment AGENCY: Minerals Management Service (MMS), Interior. ACTION: Final rule. SUMMARY: The MMS is... Subsurface Safety Valve Equipment (API Spec 14A) into its regulations. The MMS is incorporating the Eleventh...

  10. Agriculture and wildlife: ecological implications of subsurface irrigation drainage

    Science.gov (United States)

    A. Dennis Lemly

    1994-01-01

    Subsurface agricultural irrigation drainage is a wastewater with the potential to severely impact wetlands and wildlife populations. Widespread poisoning of migratory birds by drainwater contaminants has occurred in the western United States and waterfowl populations are threatened in the Pacific and Central flyways. Irrigated agriculture could produce subsurface...

  11. Influence of biofilms on colloid mobility in the subsurface

    NARCIS (Netherlands)

    Strathmann, M.; Leon Morales, C.F.; Flemming, H.C.

    2007-01-01

    Transport processes in subsurface environments are determined by complex interactions between the soil matrix and dissolved as well as particulate substances. Biofilms play an important role in the transport of colloids in the subsurface, since biofilms cover the solid soil matrix and hence

  12. Imaging the Subsurface with Upgoing Muons

    Science.gov (United States)

    Bonal, N.; Preston, L. A.; Schwellenbach, D.; Dreesen, W.; Green, A.

    2014-12-01

    We assess the feasibility of imaging the subsurface using upgoing muons. Traditional muon imaging focuses on more-prevalent downgoing muons. Muons are subatomic particles capable of penetrating the earth's crust several kilometers. Downgoing muons have been used to image the Pyramid of Khafre of Giza, various volcanoes, and smaller targets like cargo. Unfortunately, utilizing downgoing muons requires below-target detectors. For aboveground objects like a volcano, the detector is placed at the volcano's base and the top portion of the volcano is imaged. For underground targets like tunnels, the detector would have to be placed below the tunnel in a deeper tunnel or adjacent borehole, which can be costly and impractical for some locations. Additionally, detecting and characterizing subsurface features like voids from tunnels can be difficult. Typical characterization methods like sonar, seismic, and ground penetrating radar have shown mixed success. Voids have a marked density contrast with surrounding materials, so using methods sensitive to density variations would be ideal. High-energy cosmic ray muons are more sensitive to density variation than other phenomena, including gravity. Their absorption rate depends on the density of the materials through which they pass. Measurements of muon flux rate at differing directions provide density variations of the materials between the muon source (cosmic rays and neutrino interactions) and detector, much like a CAT scan. Currently, tomography using downgoing muons can resolve features to the sub-meter scale. We present results of exploratory work, which demonstrates that upgoing muon fluxes appear sufficient to achieve target detection within a few months. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  13. Subsurface Nitrogen-Cycling Microbial Communities at Uranium Contaminated Sites in the Colorado River Basin

    Science.gov (United States)

    Cardarelli, E.; Bargar, J.; Williams, K. H.; Dam, W. L.; Francis, C.

    2015-12-01

    Throughout the Colorado River Basin (CRB), uranium (U) persists as a relic contaminant of former ore processing activities. Elevated solid-phase U levels exist in fine-grained, naturally-reduced zone (NRZ) sediments intermittently found within the subsurface floodplain alluvium of the following Department of Energy-Legacy Management sites: Rifle, CO; Naturita, CO; and Grand Junction, CO. Coupled with groundwater fluctuations that alter the subsurface redox conditions, previous evidence from Rifle, CO suggests this resupply of U may be controlled by microbially-produced nitrite and nitrate. Nitrification, the two-step process of archaeal and bacterial ammonia-oxidation followed by bacterial nitrite oxidation, generates nitrate under oxic conditions. Our hypothesis is that when elevated groundwater levels recede and the subsurface system becomes anoxic, the nitrate diffuses into the reduced interiors of the NRZ and stimulates denitrification, the stepwise anaerobic reduction of nitrate/nitrite to dinitrogen gas. Denitrification may then be coupled to the oxidation of sediment-bound U(IV) forming mobile U(VI), allowing it to resupply U into local groundwater supplies. A key step in substantiating this hypothesis is to demonstrate the presence of nitrogen-cycling organisms in U-contaminated, NRZ sediments from the upper CRB. Here we investigate how the diversity and abundances of nitrifying and denitrifying microbial populations change throughout the NRZs of the subsurface by using functional gene markers for ammonia-oxidation (amoA, encoding the α-subunit of ammonia monooxygenase) and denitrification (nirK, nirS, encoding nitrite reductase). Microbial diversity has been assessed via clone libraries, while abundances have been determined through quantitative polymerase chain reaction (qPCR), elucidating how relative numbers of nitrifiers (amoA) and denitrifiers (nirK, nirS) vary with depth, vary with location, and relate to uranium release within NRZs in sediment

  14. Surface-subsurface model intercomparison: A first set of benchmark results to diagnose integrated hydrology and feedbacks.

    Science.gov (United States)

    Maxwell, R. M.; Putti, M.; Meyerhoff, S.; Delfs, J.-O.; Ferguson, I. M.; Ivanov, V.; Kim, J.; Kolditz, O.; Kollet, S. J.; Kumar, M.; Paniconi, C.; Park, Y.-J.; Phanikumar, M. S.; Sudicky, E.; Sulis, M.

    2012-04-01

    There is a growing number of large scale, complex hydrologic models with fully 2D and 3D formulations that seek to combine surface and subsurface flow. Many of these models are coupled to land-surface energy balances, biogeochemical and ecological process models, and atmospheric models. Although they are being increasingly applied for hydrologic prediction and environmental understanding, no formal verification and/or benchmarking of these models has been performed. This presentation describes the results of a first intercomparison study of surface-subsurface models. The study is based on a series of benchmark problems, and the simulation results from seven coupled hydrologic models are presented. All the models simultaneously solve adapted forms of the Richards and shallow water equations, yet they span a range of approaches for the solution of the coupled equations, including global implicit, sequential iterative, and asynchronous linking. Various strategies are used to enforce flux and pressure continuity at the surface--subsurface interface. The simulation results show good agreement for the simpler test cases, while the more complicated test cases bring out some of the differences in physical process representations and numerical resolution approaches between the models. This project funded by the United States National Science Foundation (NSF) Grant EAR-1126761.

  15. RADIOIODINE GEOCHEMISTRY IN THE SRS SUBSURFACE ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, D.; Emerson, H.; Powell, B.; Roberts, K.; Zhang, S.; Xu, C.; Schwer, K.; Li, H.; Ho, Y.; Denham, M.; Yeager, C.; Santschi, P.

    2013-05-16

    Iodine-129 is one of the key risk drivers for several Savannah River Site (SRS) performance assessments (PA), including that for the Low-Level Waste Disposal Facility in E-Area. In an effort to reduce the uncertainty associated with the conceptual model and the input values used in PA, several studies have recently been conducted dealing with radioiodine geochemistry at the SRS. The objective of this report was to review these recent studies and evaluate their implications on SRS PA calculations. For the first time, these studies measured iodine speciation in SRS groundwater and provided technical justification for assuming the presence of more strongly sorbing species (iodate and organo-iodine), and measured greater iodine sediment sorption when experiments included these newly identified species; specifically they measured greater sorption coefficients (K{sub d} values: the concentration ratio of iodine on the solid phase divided by the concentration in the aqueous phase). Based on these recent studies, new best estimates were proposed for future PA calculations. The new K{sub d} values are greater than previous recommended values. These proposed K{sub d} values reflect a better understanding of iodine geochemistry in the SRS subsurface environment, which permits reducing the associated conservatism included in the original estimates to account for uncertainty. Among the key contributing discoveries supporting the contention that the K{sub d} values should be increased are that: 1) not only iodide (I{sup -}), but also the more strongly sorbing iodate (IO{sub 3}{sup -}) species exists in SRS groundwater (average total iodine = 15% iodide, 42% iodate, and 43% organoiodine), 2) when iodine was added as iodate, the measured K{sub d} values were 2 to 6 times greater than when the iodine was added as iodide, and perhaps most importantly, 3) higher desorption (10 to 20 mL/g) than (ad)sorption (all previous studies) K{sub d} values were measured. The implications of this

  16. Entrepreneurial Couples

    DEFF Research Database (Denmark)

    Dahl, Michael S.; Van Praag, Mirjam; Thompson, Peter

    2015-01-01

    a labor market position for (female) spouses with limited alternative opportunities. This decision has positive effects: the financial benefits for each of the spouses, and especially the fe-male, are larger in co-entrepreneurial firms, both during the life of the business and post-dissolution. This also......We study motivations for and outcomes of couples starting up a joint firm, using a sample of 1,069 Danish couples that established a joint enterprise between 2001 and 2010, while comparing them to a set of comparable firms and couples. The main motivation for joint entrepreneurship is to create...

  17. Network optimization including gas lift and network parameters under subsurface uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Schulze-Riegert, R.; Baffoe, J.; Pajonk, O. [SPT Group GmbH, Hamburg (Germany); Badalov, H.; Huseynov, S. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE; Trick, M. [SPT Group, Calgary, AB (Canada)

    2013-08-01

    Optimization of oil and gas field production systems poses a great challenge to field development due to complex and multiple interactions between various operational design parameters and subsurface uncertainties. Conventional analytical methods are capable of finding local optima based on single deterministic models. They are less applicable for efficiently generating alternative design scenarios in a multi-objective context. Practical implementations of robust optimization workflows integrate the evaluation of alternative design scenarios and multiple realizations of subsurface uncertainty descriptions. Production or economic performance indicators such as NPV (Net Present Value) are linked to a risk-weighted objective function definition to guide the optimization processes. This work focuses on an integrated workflow using a reservoir-network simulator coupled to an optimization framework. The work will investigate the impact of design parameters while considering the physics of the reservoir, wells, and surface facilities. Subsurface uncertainties are described by well parameters such as inflow performance. Experimental design methods are used to investigate parameter sensitivities and interactions. Optimization methods are used to find optimal design parameter combinations which improve key performance indicators of the production network system. The proposed workflow will be applied to a representative oil reservoir coupled to a network which is modelled by an integrated reservoir-network simulator. Gas-lift will be included as an explicit measure to improve production. An objective function will be formulated for the net present value of the integrated system including production revenue and facility costs. Facility and gas lift design parameters are tuned to maximize NPV. Well inflow performance uncertainties are introduced with an impact on gas lift performance. Resulting variances on NPV are identified as a risk measure for the optimized system design. A

  18. Biogenic Carbon on Mars: A Subsurface Chauvinistic Viewpoint

    Science.gov (United States)

    Onstott, T. C.; Lau, C. Y. M.; Magnabosco, C.; Harris, R.; Chen, Y.; Slater, G.; Sherwood Lollar, B.; Kieft, T. L.; van Heerden, E.; Borgonie, G.; Dong, H.

    2015-12-01

    A review of 150 publications on the subsurface microbiology of the continental subsurface provides ~1,400 measurements of cellular abundances down to 4,800 meter depth. These data suggest that the continental subsurface biomass is comprised of ~1016-17 grams of carbon, which is higher than the most recent estimates of ~1015 grams of carbon (1 Gt) for the marine deep biosphere. If life developed early in Martian history and Mars sustained an active hydrological cycle during its first 500 million years, then is it possible that Mars could have developed a subsurface biomass of comparable size to that of Earth? Such a biomass would comprise a much larger fraction of the total known Martian carbon budget than does the subsurface biomass on Earth. More importantly could a remnant of this subsurface biosphere survive to the present day? To determine how sustainable subsurface life could be in isolation from the surface we have been studying subsurface fracture fluids from the Precambrian Shields in South Africa and Canada. In these environments the energetically efficient and deeply rooted acetyl-CoA pathway for carbon fixation plays a central role for chemolithoautotrophic primary producers that form the base of the biomass pyramid. These primary producers appear to be sustained indefinitely by H2 generated through serpentinization and radiolytic reactions. Carbon isotope data suggest that in some subsurface locations a much larger population of secondary consumers are sustained by the primary production of biogenic CH4 from a much smaller population of methanogens. These inverted biomass and energy pyramids sustained by the cycling of CH4 could have been and could still be active on Mars. The C and H isotopic signatures of Martian CH4 remain key tools in identifying potential signatures of an extant Martian biosphere. Based upon our results to date cavity ring-down spectroscopic technologies provide an option for making these measurements on future rover missions.

  19. Entrepreneurial Couples

    DEFF Research Database (Denmark)

    Dahl, Michael S.; Van Praag, Mirjam; Thompson, Peter

    with a selected set of comparable firms and couples. We find evidence that couples often establish a business together because one spouse - most commonly the female - has limited outside opportunities in the labor market. However, the financial benefits for each of the spouses, and especially the female......We study possible motivations for co-entrepenurial couples to start up a joint firm, us-ing a sample of 1,069 Danish couples that established a joint enterprise between 2001 and 2010. We compare their pre-entry characteristics, firm performance and post-dissolution private and financial outcomes......, are larger in co-entrepreneurial firms, both during the life of the business and post-dissolution. The start-up of co-entrepreneurial firms seems therefore a sound in-vestment in the human capital of both spouses as well as in the reduction of income inequality in the household. We find no evidence of non...

  20. Entrepreneurial Couples

    DEFF Research Database (Denmark)

    Dahl, Michael S.; Van Praag, Mirjam; Thompson, Peter

    with a selected set of comparable firms and couples. We find evidence that couples often establish a business together because one spouse – most commonly the female – has limited outside opportunities in the labor market. However, the financial benefits for each of the spouses, and especially the female......We study possible motivations for co-entrepenurial couples to start up a joint firm, using a sample of 1,069 Danish couples that established a joint enterprise between 2001 and 2010. We compare their pre-entry characteristics, firm performance and postdissolution private and financial outcomes......, are larger in co-entrepreneurial firms, both during the life of the business and post-dissolution. The start-up of co-entrepreneurial firms seems therefore a sound investment in the human capital of both spouses as well as in the reduction of income inequality in the household. We find no evidence of non...

  1. Microbial Mineral Colonization Across a Subsurface Redox Transition Zone

    Directory of Open Access Journals (Sweden)

    Brandon eConverse

    2015-08-01

    Full Text Available This study employed 16S rRNA gene amplicon pyrosequencing to examine the hypothesis that chemolithotrophic Fe(II-oxidizing bacteria (FeOB would preferentially colonize the Fe(II-bearing mineral biotite compared to quartz sand when the minerals were incubated in situ within a subsurface redox transition zone (RTZ at the Hanford 300 Area site in Richland, WA, USA. The work was motivated by the recently documented presence of neutral-pH chemolithotrophic FeOB capable of oxidizing structural Fe(II in primary silicate and secondary phyllosilicate minerals in 300 Area sediments and groundwater (Benzine et al., 2013. Sterilized portions of sand+biotite or sand alone were incubated in situ for five months within a multilevel sampling (MLS apparatus that spanned a ca. 2-m interval across the RTZ in two separate groundwater wells. Parallel MLS measurements of aqueous geochemical species were performed prior to deployment of the minerals. Contrary to expectations, the 16S rRNA gene libraries showed no significant difference in microbial communities that colonized the sand+biotite versus sand-only deployments. Both mineral-associated and groundwater communities were dominated by heterotrophic taxa, with organisms from the Pseudomonaceae accounting for up to 70% of all reads from the colonized minerals. These results are consistent with previous results indicating the capacity for heterotrophic metabolism (including anaerobic metabolism below the RTZ as well as the predominance of heterotrophic taxa within 300 Area sediments and groundwater. Although heterotrophic organisms clearly dominated the colonized minerals, several putative lithotrophic (NH4+, H2, Fe(II, and HS- oxidizing taxa were detected in significant abundance above and within the RTZ. Such organisms may play a role in the coupling of anaerobic microbial metabolism to oxidative pathways with attendant impacts on elemental cycling and redox-sensitive contaminant behavior in the vicinity of the

  2. Mechanism and structure of subsurface explosions in granular media

    Science.gov (United States)

    Lai, Shuyue; Houim, Ryan W.; Oran, Elaine S.

    2017-09-01

    Numerical simulations are performed to study the effects of proposed subsurface explosions for ejecting low-density regolith (that is, layers of rocky, granular material covering bedrock) from the surface of asteroids and comets. The numerical model solves two sets of coupled Euler equations, one for the gaseous phase and one for the granular phase, and is valid for a wide range of particle volume fractions. The specific conditions simulate an explosion in which the regolith, here a granular-gas mixture, consists of spherical particles with diameters of 1 μ m and the gas above and inside of the particle layer is at 10 Pa and 100 K. A preliminary one-dimensional computation describes the structure of a granular shock formed from a spherical explosion. The two-dimensional axisymmetric calculations show that the explosion creates a cavity in the granular phase, and this cavity expands radially until it breaks through the surface. A blast wave is created during the explosion, initiating the particle motions and forming a granular shock. The particles accumulate behind the granular shock to form a region with high particle volume fractions. An increase in gas-phase velocity at the contact surface is due to a sudden reduction of gas-phase volume, which is called the "nozzling effect." A weak shock in the gas phase is induced by the granular shock, which propagates radially. As the initial particle volume fraction increases, the propagation velocity of the granular shock increases. It is shown that there is a power-law relation between the explosion radius and time, and that this result is consistent with the blast-wave theory. At lower background temperatures, the velocities of both phases decrease, and this leads to more compact structures in the granular phase.

  3. The DOE Subsurface Microbial Culture Collection (SMCC)

    Energy Technology Data Exchange (ETDEWEB)

    Balkwill, David L.

    2006-05-23

    The primary activities associated with maintenance of the Subsurface Microbial Culture Collection (SMCC) were designed to ensure that the collection served as a valuable resource to DOE-funded and other scientists, especially DOE-funded scientists associated with the NABIR Program. These activities were carried out throughout the period covered by this report and in-cluded: (1) assistance in the selection of cultures for research, (2) distribution of cultures and/or data on request, (3) incorporation of newly isolated microbial strains, (4) preservation of newly isolated strains, (5) partial characterization of newly isolated strains, (6) development and main-tenance of representative subsets of cultures, (6) screening of SMCC strains for specific charac-teristics, (7) phylogenetic characterization of SMCC strains, (8) development and maintenance of a SMCC website, (9) maintenance of the SMCC databases, (10) archiving of SMCC records, and (11) quality assurance/quality control (QA/QC) activities. We describe in the Final Technical Report our accomplishments related to these activities during the period covered by this report.

  4. [Clogging characteristics of the subsurface flow wetland].

    Science.gov (United States)

    Yan, Lu; Wang, Shi-He; Huang, Juan; Liu, Yang; Wang, Feng

    2008-03-01

    In order to resolve clogging problem of constructed wetlands caused by improper design or imperfect management and reveal the clogging mechanism, clogging characteristics of the horizontal flow reed wetland and vertical flow reed wetland were studied. Operation stabilities of two types of wetlands were compared. It shows that organic matter accumulates in medium and the concentration is 1.5% - 5%. It mostly occurs in the fore section of top layer in wetland and the concentration is 4% - 5%. The negative correlation between the organic matter content and the subsurface depth was demonstrated. The clogging mechanisms in the horizontal flow wetland and the vertical flow wetland are different. The hydraulic retention time of the horizontal flow wetland is 3.5154 d which is shortened by 21.88%. While the hydraulic retention time of the vertical flow wetland is 5.4648 d and extended by 21.44%. The results indicate that clogging decreases the treatment capacity and running stability conspicuously. The clogging phenomenon of the vertical flow wetland is worse comparatively.

  5. Subsurface flow in lowland river gravel bars

    Science.gov (United States)

    Bray, E. N.; Dunne, T.

    2017-09-01

    Geomorphic and hydraulic processes, which form gravel bars in large lowland rivers, have distinctive characteristics that control the magnitude and spatial patterns of infiltration and exfiltration between rivers and their immediate subsurface environments. We present a bedform-infiltration relation together with a set of field measurements along two reaches of the San Joaquin River, CA to illustrate the conditions required for infiltration and exfiltration of flow between a stream and its undulating bed, and a numerical model to investigate the factors that affect paths and residence times of flow through barforms at different discharges. It is shown that asymmetry of bar morphology is a first-order control on the extent and location of infiltration, which would otherwise produce equal areas of infiltration and exfiltration under the assumption of sinusoidal bedforms. Hydraulic conductivity varies by orders of magnitude due to fine sediment accumulation and downstream coarsening related to the process of bar evolution. This systematic variability not only controls the magnitude of infiltration, but also the residence time of flow through the bed. The lowest hydraulic conductivity along the reach occurred where the difference between the topographic gradient and the water-surface gradient is at a maximum and thus where infiltration would be greatest into a homogeneous bar, indicating the importance of managing sand supply to maintain the ventilation and flow through salmon spawning riffles. Numerical simulations corroborate our interpretation that infiltration patterns and rates are controlled by distinctive features of bar morphology.

  6. Integrating experimental and numerical methods for a scenario-based quantitative assessment of subsurface energy storage options

    Science.gov (United States)

    Kabuth, Alina; Dahmke, Andreas; Hagrey, Said Attia al; Berta, Márton; Dörr, Cordula; Koproch, Nicolas; Köber, Ralf; Köhn, Daniel; Nolde, Michael; Tilmann Pfeiffer, Wolf; Popp, Steffi; Schwanebeck, Malte; Bauer, Sebastian

    2016-04-01

    Within the framework of the transition to renewable energy sources ("Energiewende"), the German government defined the target of producing 60 % of the final energy consumption from renewable energy sources by the year 2050. However, renewable energies are subject to natural fluctuations. Energy storage can help to buffer the resulting time shifts between production and demand. Subsurface geological structures provide large potential capacities for energy stored in the form of heat or gas on daily to seasonal time scales. In order to explore this potential sustainably, the possible induced effects of energy storage operations have to be quantified for both specified normal operation and events of failure. The ANGUS+ project therefore integrates experimental laboratory studies with numerical approaches to assess subsurface energy storage scenarios and monitoring methods. Subsurface storage options for gas, i.e. hydrogen, synthetic methane and compressed air in salt caverns or porous structures, as well as subsurface heat storage are investigated with respect to site prerequisites, storage dimensions, induced effects, monitoring methods and integration into spatial planning schemes. The conceptual interdisciplinary approach of the ANGUS+ project towards the integration of subsurface energy storage into a sustainable subsurface planning scheme is presented here, and this approach is then demonstrated using the examples of two selected energy storage options: Firstly, the option of seasonal heat storage in a shallow aquifer is presented. Coupled thermal and hydraulic processes induced by periodic heat injection and extraction were simulated in the open-source numerical modelling package OpenGeoSys. Situations of specified normal operation as well as cases of failure in operational storage with leaking heat transfer fluid are considered. Bench-scale experiments provided parameterisations of temperature dependent changes in shallow groundwater hydrogeochemistry. As a

  7. What's down below? Current and potential future applications of geophysical techniques to identify subsurface permafrost conditions (Invited)

    Science.gov (United States)

    Douglas, T. A.; Bjella, K.; Campbell, S. W.

    2013-12-01

    For infrastructure design, operations, and maintenance requirements in the North the ability to accurately and efficiently detect the presence (or absence) of ground ice in permafrost terrains is a serious challenge. Ground ice features including ice wedges, thermokarst cave-ice, and segregation ice are present in a variety of spatial scales and patterns. Currently, most engineering applications use borehole logging and sampling to extrapolate conditions at the point scale. However, there is high risk of over or under estimating the presence of frozen or unfrozen features when relying on borehole information alone. In addition, boreholes are costly, especially for planning linear structures like roads or runways. Predicted climate warming will provide further challenges for infrastructure development and transportation operations where permafrost degradation occurs. Accurately identifying the subsurface character in permafrost terrains will allow engineers and planners to cost effectively create novel infrastructure designs to withstand the changing environment. There is thus a great need for a low cost rapidly deployable, spatially extensive means of 'measuring' subsurface conditions. Geophysical measurements, both terrestrial and airborne, have strong potential to revolutionize our way of mapping subsurface conditions. Many studies in continuous and discontinuous permafrost have used geophysical measurements to identify discrete features and repeatable patterns in the subsurface. The most common measurements include galvanic and capacitive coupled resistivity, ground penetrating radar, and multi frequency electromagnetic induction techniques. Each of these measurements has strengths, weaknesses, and limitations. By combining horizontal geophysical measurements, downhole geophysics, multispectral remote sensing images, LiDAR measurements, and soil and vegetation mapping we can start to assemble a holistic view of how surface conditions and standoff measurements

  8. Final Technical Report: Viral Infection of Subsurface Microorganisms and Metal/Radionuclide Transport

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Karrie A.; Bender, Kelly S.; Li, Yusong

    2013-09-28

    Microbially mediated metabolisms have been identified as a significant factor either directly or indirectly impacting the fate and transport of heavy metal/radionuclide contaminants. To date microorganisms have been isolated from contaminated environments. Examination of annotated finished genome sequences of many of these subsurface isolates from DOE sites, revealed evidence of prior viral infection. To date the role that viruses play influencing microbial mortality and the resulting community structure which directly influences biogeochemical cycling in soils and sedimentary environments remains poorly understood. The objective of this exploratory study was to investigate the role of viral infection of subsurface bacteria and the formation of contaminant-bearing viral particles. This objective was approached by examining the following working hypotheses: (i) subsurface microorganisms are susceptible to viral infections by the indigenous subsurface viral community, and (ii) viral surfaces will adsorb heavy metals and radionuclides. Our results have addressed basic research needed to accomplish the BER Long Term Measure to provide sufficient scientific understanding such that DOE sites would be able to incorporate coupled physical, chemical and biological processes into decision making for environmental remediation or natural attenuation and long-term stewardship by establishing viral-microbial relationships on the subsequent fate and transport of heavy metals and radionuclides. Here we demonstrated that viruses play a significant role in microbial mortality and community structure in terrestrial subsurface sedimentary systems. The production of viral-like particles within subsurface sediments in response to biostimulation with dissolved organic carbon and a terminal electron acceptor resulted in the production of viral-like particles. Organic carbon alone did not result in significant viral production and required the addition of a terminal electron acceptor

  9. Physico-chemical and Mineralogical Characterisation of Subsurface ...

    African Journals Online (AJOL)

    , moisture content, bulk density (Db), porosity, surface area, pH, electrical conductivity (EC), and cation exchange ... Grain size analyses of the subsurface sediments revealed sandy loam, silty loam, and silt as the main textural classes.

  10. West Twin Creek Alaska Subsurface Bromide Tracer Experiment, 2015

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data was produced as part of a subsurface tracer experiment performed on a boreal hillslope in July, 2015. The data is separated into three files: 'Well...

  11. A hydrogen-based subsurface microbial community dominated by methanogens

    Science.gov (United States)

    Chapelle, F.H.; O'Neil, Kyle; Bradley, P.M.; Methe, B.A.; Ciufo, S.A.; Knobel, L.L.; Lovley, D.R.

    2002-01-01

    The search for extraterrestrial life may be facilitated if ecosystems can be found on Earth that exist under conditions analogous to those present on other planets or moons. It has been proposed, on the basis of geochemical and thermodynamic considerations, that geologically derived hydrogen might support subsurface microbial communities on Mars and Europa in which methanogens form the base of the ecosystem1-5. Here we describe a unique subsurface microbial community in which hydrogen-consuming, methane-producing Archaea far outnumber the Bacteria. More than 90% of the 16s ribosomal DNA sequences recovered from hydrothermal waters circulating through deeply buried igneous rocks in Idaho are related to hydrogen-using methanogenic microorganisms. Geochemical characterization indicates that geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. These results demonstrate that hydrogen-based methanogenic communities do occur in Earth's subsurface, providing an analogue for possible subsurface microbial ecosystems on other planets.

  12. Multi-Robot Systems for Subsurface Planetary Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a heterogeneous multi-robot team developed as a platform for effective subsurface planetary exploration. State-of-art robotic exploration...

  13. Sub-Surface Oil Monitoring Cruise (GU1002, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Objectives were to evaluate ability of acoustic echosounder measurements to detect and localize a sub-surface plume of oil or related hydrocarbons released from the...

  14. Broadband Counter-Wound Spiral Antenna for Subsurface Radar Applications

    National Research Council Canada - National Science Library

    Yong, Lim

    2003-01-01

    .... An overall design strategy is outlined, together with a more detailed treatment of the ground-penetrating radar supersystems and topics which are relevant to effective subsurface radar operation...

  15. Recalcitrant Carbonaceous Material: A Source of Electron Donors for Anaerobic Microbial Metabolisms in the Subsurface?

    Science.gov (United States)

    Nixon, S. L.; Montgomery, W.; Sephton, M. A.; Cockell, C. S.

    2014-12-01

    More than 90% of organic material on Earth resides in sedimentary rocks in the form of kerogens; fossilized organic matter formed through selective preservation of high molecular weight biopolymers under anoxic conditions. Despite its prevalence in the subsurface, the extent to which this material supports microbial metabolisms is unknown. Whilst aerobic microorganisms are known to derive energy from kerogens within shales, utilization in anaerobic microbial metabolisms that proliferate in the terrestrial subsurface, such as microbial iron reduction, has yet to be demonstrated. Data are presented from microbial growth experiments in which kerogens and shales were supplied as the sole electron donor source for microbial iron reduction by an enrichment culture. Four well-characterized kerogens samples (representative of Types I-IV, classified by starting material), and two shale samples, were assessed. Organic analysis was carried out to investigate major compound classes present in each starting material. Parallel experiments were conducted to test inhibition of microbial iron reduction in the presence of each material when the culture was supplied with a full redox couple. The results demonstrate that iron-reducing microorganisms in this culture were unable to use kerogens and shales as a source of electron donors for energy acquisition, despite the presence of compound classes known to support this metabolism. Furthermore, the presence of these materials was found to inhibit microbial iron reduction to varying degrees, with some samples leading to complete inhibition. These results suggest that recalcitrant carbonaceous material in the terrestrial subsurface is not available for microbial iron reduction and similar metabolisms, such as sulphate-reduction. Further research is needed to investigate the inhibition exerted by these materials, and to assess whether these findings apply to other microbial consortia. These results may have significant implications for

  16. The effect of pavement-watering on subsurface pavement temperatures

    OpenAIRE

    Hendel, Martin; Royon, Laurent

    2015-01-01

    International audience; Pavement-watering is currently viewed as a potential climate change adaptation and urban heat island mitigation technique. The effects of pavement-watering on pavement temperature measured 5 cm deep are presented and discussed. Subsurface temperature measurements could not be used to improve or optimize pavement-watering methods as was seen in previous work on surface temperatures or subsurface pavement heat flux measurements.

  17. DWH MC 252: Subsurface Oil Transport

    Science.gov (United States)

    Beegle-Krause, C. J.; Boyer, T.; Murray, D.

    2010-12-01

    , previous research and modeling were combined to tell the story of the DWH MC 252 from the subsurface perspective. The Comprehensive Deepwater Oil and Gas model (CDOG, Yapa and Xie, 2005), and the General NOAA Operational Modeling Environment (GNOME, Beegle-Krause, 1999) were used with the NOAA Gulf of Mexico Model nowcast/forecast model to understand the 3D evolution of the subsurface spill. Model/observational comparisons are favorable, though limitations of the available models are apparent. Historical perspective on Thunder Horse (a deepwater well incident that was a dress-rehearsal for the DWH MC 252, Beegle-Krause and Walton, 2004), transitioning models from research to operations, and research needs will also be discussed.

  18. Ecosystem Modeling in the South Central US: A Synthesis of Current Models toward the Development of Coupled Models

    Science.gov (United States)

    Kc, M.

    2015-12-01

    Ecosystem services and products are the foundation of sustainability for regional and global economy since we are directly or indirectly dependent on the ecosystem services like food, livestock, water, air, wildlife etc. It has been increasingly recognized that for sustainability concerns, the conservation problems need to be addressed in the context of entire ecosystems. This approach known as the ecosystem approach is fundamental to managing earth's finite resources since it addresses the interactions that link biotic systems, of which human, flora and fauna are integral parts, with the physical systems on which they depend. This approach is even more vital in the 21st century with formidable increasing human population and rapid changes in global environment. This study is being conducted to find the state of the science of ecosystem models in the South-Central region of US. The propose of the project is to conduct a systematic review and synthesize relevant information on the current state of the science of ecosystem modeling in the South-Central region of US toward coupling these models with climate, agronomic, hydrologic, economic or management models to better represent ecosystem dynamics as affected by climate change and human activities; and hence gain more reliable predictions of future ecosystem functions and service in the region. Better understandings of such processes will increase our ability to predict the ecosystem responses and feedbacks to environmental and human induced change in the region so that decision makers can make an informed management decisions of the ecosystem.

  19. Seismic Imaging of Open Subsurface Fractures

    Science.gov (United States)

    Myers, S. C.; Pitarka, A.; Matzel, E.; Aguiar, A. C.

    2015-12-01

    Injection of high-pressure fluid into the subsurface is proven to stimulate geothermal, oil, and gas production by opening cracks that increase permeability. The effectiveness of increasing permeability by high-pressure injection has been revolutionized by the introduction of "proppants" into the injected fluid to keep cracks open after the pressure of the stimulation activity ends. The network of fractures produced during stimulation is most commonly inferred by the location of micro-earthquakes. However, existing (closed) fractures may open aseismically, so the whole fracture network may not be imaged by micro-seismic locations alone. Further, whether all new fractures remain open and for how long remains unclear. Open cracks, even fluid-filled cracks, scatter seismic waves because traction forces are not transmitted across the gap. Numerical simulation confirms that an open crack with dimensions on the order of 10 meters can scatter enough seismic energy to change the coda of seismic signals. Our simulations show that changes in seismic coda due to newly opened fractures are only a few percent of peak seismogram amplitudes, making signals from open cracks difficult to identify. We are developing advanced signal processing methods to identify candidate signals that originate from open cracks. These methods are based on differencing seismograms that are recorded before and after high-pressure fluid injection events to identify changes in the coda. The origins of candidate signals are located using time-reversal techniques to determine if the signals are indeed associated with a coherent structure. The source of scattered energy is compared to micro-seismic event locations to determine whether cracks opened seismically or aseismically. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-675612.

  20. Paracetamol removal in subsurface flow constructed wetlands

    Science.gov (United States)

    Ranieri, Ezio; Verlicchi, Paola; Young, Thomas M.

    2011-07-01

    SummaryIn this study two pilot scale Horizontal Subsurface Flow Constructed Wetlands (HSFCWs) near Lecce, Italy, planted with different macrophytes ( Phragmites australis and Typha latifolia) and an unplanted control were assessed for their effectiveness in removing paracetamol. Residence time distributions (RTDs) for the two beds indicated that the Typha bed was characterized by a void volume fraction (porosity) of 0.16 and exhibited more ideal plug flow behavior (Pe = 29.7) than the Phragmites bed (Pe = 26.7), which had similar porosity. The measured hydraulic residence times in the planted beds were 35.8 and 36.7 h when the flow was equal to 1 m 3/d. The Phragmites bed exhibited a range of paracetamol removals from 51.7% for a Hydraulic Loading Rate (HLR) of 240 mm/d to 87% with 120 mm/d HLR and 99.9% with 30 mm/d. The Typha bed showed a similar behavior with percentages of removal slightly lower, ranging from 46.7% (HLR of 240 mm/d) to >99.9% (hydraulic loading rate of 30 mm/d). At the same HLR values the unplanted bed removed between 51.3% and 97.6% of the paracetamol. In all three treatments the paracetamol removal was higher with flow of 1 m 3/d and an area of approx. 7.5 m 2 (half bed) than in the case of flow equal to 0.5 m 3/d with a surface treatment of approx. 3.75 m 2. A first order model for paracetamol removal was evaluated and half lives of 5.16 to 10.2 h were obtained.

  1. Integrating surrogate models into subsurface simulation framework allows computation of complex reactive transport scenarios

    Science.gov (United States)

    De Lucia, Marco; Kempka, Thomas; Jatnieks, Janis; Kühn, Michael

    2017-04-01

    Reactive transport simulations - where geochemical reactions are coupled with hydrodynamic transport of reactants - are extremely time consuming and suffer from significant numerical issues. Given the high uncertainties inherently associated with the geochemical models, which also constitute the major computational bottleneck, such requirements may seem inappropriate and probably constitute the main limitation for their wide application. A promising way to ease and speed-up such coupled simulations is achievable employing statistical surrogates instead of "full-physics" geochemical models [1]. Data-driven surrogates are reduced models obtained on a set of pre-calculated "full physics" simulations, capturing their principal features while being extremely fast to compute. Model reduction of course comes at price of a precision loss; however, this appears justified in presence of large uncertainties regarding the parametrization of geochemical processes. This contribution illustrates the integration of surrogates into the flexible simulation framework currently being developed by the authors' research group [2]. The high level language of choice for obtaining and dealing with surrogate models is R, which profits from state-of-the-art methods for statistical analysis of large simulations ensembles. A stand-alone advective mass transport module was furthermore developed in order to add such capability to any multiphase finite volume hydrodynamic simulator within the simulation framework. We present 2D and 3D case studies benchmarking the performance of surrogates and "full physics" chemistry in scenarios pertaining the assessment of geological subsurface utilization. [1] Jatnieks, J., De Lucia, M., Dransch, D., Sips, M.: "Data-driven surrogate model approach for improving the performance of reactive transport simulations.", Energy Procedia 97, 2016, p. 447-453. [2] Kempka, T., Nakaten, B., De Lucia, M., Nakaten, N., Otto, C., Pohl, M., Chabab [Tillner], E., Kühn, M

  2. Seismic Techniques for Subsurface Voids Detection

    Science.gov (United States)

    Gritto, Roland; Korneev, Valeri; Elobaid Elnaiem, Ali; Mohamed, Fathelrahman; Sadooni, Fadhil

    2016-04-01

    orthogonal transmission surveys to detect and locate the object. Furthermore, we showed that ambient noise recordings may generate data with sufficient signal-to-noise ratio to successfully detect and locate subsurface voids. Being able to use ambient noise recordings would eliminate the need to employ active seismic sources that are time consuming and more expensive to operate.

  3. Geophysical subsurface imaging and interface identification.

    Energy Technology Data Exchange (ETDEWEB)

    Pendley, Kevin; Bochev, Pavel Blagoveston; Day, David Minot; Robinson, Allen Conrad; Weiss, Chester Joseph

    2005-09-01

    Electromagnetic induction is a classic geophysical exploration method designed for subsurface characterization--in particular, sensing the presence of geologic heterogeneities and fluids such as groundwater and hydrocarbons. Several approaches to the computational problems associated with predicting and interpreting electromagnetic phenomena in and around the earth are addressed herein. Publications resulting from the project include [31]. To obtain accurate and physically meaningful numerical simulations of natural phenomena, computational algorithms should operate in discrete settings that reflect the structure of governing mathematical models. In section 2, the extension of algebraic multigrid methods for the time domain eddy current equations to the frequency domain problem is discussed. Software was developed and is available in Trilinos ML package. In section 3 we consider finite element approximations of De Rham's complex. We describe how to develop a family of finite element spaces that forms an exact sequence on hexahedral grids. The ensuing family of non-affine finite elements is called a van Welij complex, after the work [37] of van Welij who first proposed a general method for developing tangentially and normally continuous vector fields on hexahedral elements. The use of this complex is illustrated for the eddy current equations and a conservation law problem. Software was developed and is available in the Ptenos finite element package. The more popular methods of geophysical inversion seek solutions to an unconstrained optimization problem by imposing stabilizing constraints in the form of smoothing operators on some enormous set of model parameters (i.e. ''over-parametrize and regularize''). In contrast we investigate an alternative approach whereby sharp jumps in material properties are preserved in the solution by choosing as model parameters a modest set of variables which describe an interface between adjacent regions in

  4. Intercellular Genomics of Subsurface Microbial Colonies

    Energy Technology Data Exchange (ETDEWEB)

    Ortoleva, Peter [Indiana Univ., Bloomington, IN (United States); Tuncay, Kagan [Indiana Univ., Bloomington, IN (United States); Gannon, Dennis [Indiana Univ., Bloomington, IN (United States); Meile, Christof [Indiana Univ., Bloomington, IN (United States)

    2007-02-14

    This report summarizes progress in the second year of this project. The objective is to develop methods and software to predict the spatial configuration, properties and temporal evolution of microbial colonies in the subsurface. To accomplish this, we integrate models of intracellular processes, cell-host medium exchange and reaction-transport dynamics on the colony scale. At the conclusion of the project, we aim to have the foundations of a predictive mathematical model and software that captures the three scales of these systems – the intracellular, pore, and colony wide spatial scales. In the second year of the project, we refined our transcriptional regulatory network discovery (TRND) approach that utilizes gene expression data along with phylogenic similarity and gene ontology analyses and applied it successfully to E.coli, human B cells, and Geobacter sulfurreducens. We have developed a new Web interface, GeoGen, which is tailored to the reconstruction of microbial TRNs and solely focuses on Geobacter as one of DOE’s high priority microbes. Our developments are designed such that the frameworks for the TRND and GeoGen can readily be used for other microbes of interest to the DOE. In the context of modeling a single bacterium, we are actively pursuing both steady-state and kinetic approaches. The steady-state approach is based on a flux balance that uses maximizing biomass growth rate as its objective, subjected to various biochemical constraints, for the optimal values of reaction rates and uptake/release of metabolites. For the kinetic approach, we use Karyote, a rigorous cell model developed by us for an earlier DOE grant and the DARPA BioSPICE Project. We are also investigating the interplay between bacterial colonies and environment at both pore and macroscopic scales. The pore scale models use detailed representations for realistic porous media accounting for the distribution of grain size whereas the macroscopic models employ the Darcy-type flow

  5. Characterization of accumulated precipitates during subsurface iron removal

    KAUST Repository

    Van Halem, Doris

    2011-01-01

    The principle of subsurface iron removal for drinking water supply is that aerated water is periodically injected into the aquifer through a tube well. On its way into the aquifer, the injected O2-rich water oxidizes adsorbed Fe 2+, creating a subsurface oxidation zone. When groundwater abstraction is resumed, the soluble Fe 2+ is adsorbed and water with reduced Fe concentrations is abstracted for multiple volumes of the injection water. In this article, Fe accumulation deposits in the aquifer near subsurface treatment wells were identified and characterized to assess the sustainability of subsurface iron removal regarding clogging of the aquifer and the potential co-accumulation of other groundwater constituents, such as As. Chemical extraction of soil samples, with Acid-Oxalate and HNO3, showed that Fe had accumulated at specific depths near subsurface iron removal wells after 12 years of operation. Whether it was due to preferred flow paths or geochemical mineralogy conditions; subsurface iron removal clearly favoured certain soil layers. The total Fe content increased between 11.5 and 390.8 mmol/kg ds in the affected soil layers, and the accumulated Fe was found to be 56-100% crystalline. These results suggest that precipitated amorphous Fe hydroxides have transformed to Fe hydroxides of higher crystallinity. These crystalline, compact Fe hydroxides have not noticeably clogged the investigated well and/or aquifer between 1996 and 2008. The subsurface iron removal wells even need less frequent rehabilitation, as drawdown increases more slowly than in normal production wells. Other groundwater constituents, such as Mn, As and Sr were found to co-accumulate with Fe. Acid extraction and ESEM-EDX showed that Ca occurred together with Fe and by X-ray Powder Diffraction it was identified as calcite. © 2010 Elsevier Ltd. All rights reserved.

  6. Welding shield for coupling heaters

    Science.gov (United States)

    Menotti, James Louis

    2010-03-09

    Systems for coupling end portions of two elongated heater portions and methods of using such systems to treat a subsurface formation are described herein. A system may include a holding system configured to hold end portions of the two elongated heater portions so that the end portions are abutted together or located near each other; a shield for enclosing the end portions, and one or more inert gas inlets configured to provide at least one inert gas to flush the system with inert gas during welding of the end portions. The shield may be configured to inhibit oxidation during welding that joins the end portions together. The shield may include a hinged door that, when closed, is configured to at least partially isolate the interior of the shield from the atmosphere. The hinged door, when open, is configured to allow access to the interior of the shield.

  7. Subsurface and terrain controls on runoff generation in deep soil landscapes

    Science.gov (United States)

    Mallard, John; McGlynn, Brian; Richter, Daniel

    2017-04-01

    -occurred with streamflow generation. Our initial findings suggest that characterizing the terrain of a watershed must be coupled with the subsurface soil hydrology in order to understand spatiotemporal patterns of streamflow generation in regions possessing both complex vertical structure and terrain.

  8. Subsurface Fluid Escape at the Palmachim Disturbance in the Levant Basin, SE Mediterranean Sea

    Science.gov (United States)

    Eruteya, Ovie; Waldmann, Nicolas; Reshef, Moshe; Ben-Avraham, Zvi

    2017-04-01

    Submarine fluid escape is a pervasive phenomenon occurring along continental margins and is usually deciphered by the presence of geomorphic structures such as pockmarks, mud volcanoes and mounds. In the present study we have analyzed a new high-resolution three-dimensional seismic reflection dataset covering the compressive domain of the Palmachim disturbance. The Palmachim disturbance is a 20 x 10 km salient slump body offshore southern Israel, which detach above the Messinian evaporites and extend upwards to the present day seafloor. In this contribution we present a new set of pockmarks having diameters and depths of up to 400 and 35 m, respectively. Interestingly, the majority of these pockmarks are localized on the crest and flanks of seafloor ridges associated with the evolution of the Palmachim disturbance. We show that significant populations of these pockmarks are coupled with subsurface fluid flow conduits above fault system detaching onto the Messinian evaporites, within a complex region of their withdrawal. Other pockmarks are related to regions characterized by channel-levee complex in the supra-evaporites stratigraphy. We propose a dual fluid source driving subsurface fluid plumbing within the vicinity of the Palmachim disturbance: (1) shallow fluid source derived from the channel-levee complex and likewise the possibility of sapropels within the supra-evaporites stratigraphy; and (2) a deeper-source of fluids emanating from Pre-Messinian reservoirs and possible intra-Messinian clastic sequence. Structural deformations associated with the Palmachim disturbance may as well act as seal-by-pass systems whereby fluids from the Messinian realm can be channeled to shallower levels through trust faults. The presence of mass transport deposits and channel-levee complexes in Pliocene overburden may serve as transient reservoirs for redistributing and focusing fluids toward the seafloor for expulsion. The findings from this study are relevant for better

  9. The Mediterranean subsurface chlorophyll dynamic and its impact on the Mediterranean bioregions.

    Science.gov (United States)

    Palmiéri, Julien; Dutay, Jean-Claude; Dortenzio, Fabrizio; Richon, Camille; Houpert, Loïc; Bopp, Laurent

    2017-04-01

    Ocean bioregions are generally defined using remotely-sensed sea surface chlorophyll fields, based on the assumption that surface chlorophyll is representative of euphotic layer phytoplankton biomass. Here we investigate the impact of subsurface phytoplankton dynamics on the characterisation of ocean bioregions. The Mediterranean Sea is known for its contrasting bioregimes despite its limited area, and represents an appropriate case for this study. We modelled this area using a high resolution regional dynamical model, NEMO-MED12, coupled to a biogeochemical model, PISCES, and focused our analysis on the bioregions derived from lower trophic levels. Validated by Bio-Argo observations, our model shows that chlorophyll phenology can be significantly different when estimated from surface concentrations or integrated over the euphotic layer. This was found in both low chlorophyll, oligotrophic bioregions as well as in high chlorophyll, bloom bioregions. The underlying reason for this difference is the importance of subsurface phytoplankton dynamics, in particular those associated with the Deep Chlorophyll Maximum (DCM) at the base of the upper mixed layer. Subsurface phytoplankton are found to significantly impact the bloom bioregions, while in oligotrophic regions are of similar productivity to the surface layer. Consequently, our results show that surface chlorophyll is not representative of total phytoplankton biomass. Analysis of the DCM finds that it is extremely homogeneous throughout the Mediterranean Sea, and that it follows the annual cycle of solar radiation. In the most oligotrophic bioregion, the total phytoplankton biomass is almost constant along the year, implying that the summertime DCM biomass increase is not due to DCM photoacclimation, nor an increase of DCM production, but instead of the "migration" - with photoacclimation - of surface phytoplankton into the DCM.

  10. Peeking Beneath the Caldera: Communicating Subsurface Knowledge of Newberry Volcano

    Science.gov (United States)

    Mark-Moser, M.; Rose, K.; Schultz, J.; Cameron, E.

    2016-12-01

    "Imaging the Subsurface: Enhanced Geothermal Systems and Exploring Beneath Newberry Volcano" is an interactive website that presents a three-dimensional subsurface model of Newberry Volcano developed at National Energy Technology Laboratory (NETL). Created using the Story Maps application by ArcGIS Online, this format's dynamic capabilities provide the user the opportunity for multimedia engagement with the datasets and information used to build the subsurface model. This website allows for an interactive experience that the user dictates, including interactive maps, instructive videos and video capture of the subsurface model, and linked information throughout the text. This Story Map offers a general background on the technology of enhanced geothermal systems and the geologic and development history of Newberry Volcano before presenting NETL's modeling efforts that support the installation of enhanced geothermal systems. The model is driven by multiple geologic and geophysical datasets to compare and contrast results which allow for the targeting of potential EGS sites and the reduction of subsurface uncertainty. This Story Map aims to communicate to a broad audience, and provides a platform to effectively introduce the model to researchers and stakeholders.

  11. Lower-Temperature Subsurface Layout and Ventilation Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Christine L. Linden; Edward G. Thomas

    2001-06-20

    This analysis combines work scope identified as subsurface facility (SSF) low temperature (LT) Facilities System and SSF LT Ventilation System in the Technical Work Plan for Subsurface Design Section FY 01 Work Activities (CRWMS M&O 2001b, pp. 6 and 7, and pp. 13 and 14). In accordance with this technical work plan (TWP), this analysis is performed using AP-3.10Q, Analyses and Models. It also incorporates the procedure AP-SI.1Q, Software Management. The purpose of this analysis is to develop an overall subsurface layout system and the overall ventilation system concepts that address a lower-temperature operating mode for the Monitored Geologic Repository (MGR). The objective of this analysis is to provide a technical design product that supports the lower-temperature operating mode concept for the revision of the system description documents and to provide a basis for the system description document design descriptions. The overall subsurface layout analysis develops and describes the overall subsurface layout, including performance confirmation facilities (also referred to as Test and Evaluation Facilities) for the Site Recommendation design. This analysis also incorporates current program directives for thermal management.

  12. Subsurface Biodegradation in a Fractured Basement Reservoir, Shropshire, UK

    Science.gov (United States)

    Parnell, John; Baba, Mas'ud; Bowden, Stephen; Muirhead, David

    2017-04-01

    Subsurface Biodegradation in a Fractured Basement Reservoir, Shropshire, UK. John Parnell, Mas'ud Baba, Stephen Bowden, David Muirhead Subsurface biodegradation in current oil reservoirs is well established, but there are few examples of fossil subsurface degradation. Biomarker compositions of viscous and solid oil residues ('bitumen') in fractured Precambrian and other basement rocks below the Carboniferous cover in Shropshire, UK, show that they are variably biodegraded. High levels of 25-norhopanes imply that degradation occurred in the subsurface. Lower levels of 25-norhopanes occur in active seepages. Liquid oil trapped in fluid inclusions in mineral veins in the fractured basement confirm that the oil was emplaced fresh before subsurface degradation. A Triassic age for the veins implies a 200 million year history of hydrocarbon migration in the basement rocks. The data record microbial colonization of a fractured basement reservoir, and add to evidence in modern basement aquifers for microbial activity in deep fracture systems. Buried basement highs may be especially favourable to colonization, through channelling fluid flow to shallow depths and relatively low temperatures

  13. Asset management to support urban land and subsurface management.

    Science.gov (United States)

    Maring, Linda; Blauw, Maaike

    2018-02-15

    Pressure on urban areas increases by demographic and climate change. To enable healthy, adaptive and liveable urban areas different strategies are needed. One of the strategies is to make better use of subsurface space and its functions. Asset management of the Subsurface (AMS) contributes to this. Asset management provides transparency of trade-offs between performance, cost and risks throughout the entire lifecycle of these assets. AMS is based on traditional asset management methods, but it does not only take man-made assets in the subsurface into account. AMS also considers the natural functions that the subsurface, including groundwater, has to offer (ecosystem services). A Dutch community of practice consisting of national and municipal authorities, a consultancy-engineering and a research institute are developing AMS in practice in order to 1) enhance the urban underground space planning (using its benefits, avoiding problems) and 2) use, manage and maintain the (urban) subsurface and its functions. The method is currently still under development. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. An Electrode-based approach for monitoring in situ microbial activity during subsurface bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, K.H.; Nevin, K.P.; Franks, A.; Englert, A.; Long, P.E.; Lovley, D.R.

    2009-11-15

    Current production by microorganisms colonizing subsurface electrodes and its relationship to substrate availability and microbial activity was evaluated in an aquifer undergoing bioremediation. Borehole graphite anodes were installed downgradient from a region of acetate injection designed to stimulate bioreduction of U(VI); cathodes consisted of graphite electrodes embedded at the ground surface. Significant increases in current density ({<=}50 mA/m{sup 2}) tracked delivery of acetate to the electrodes, dropping rapidly when acetate inputs were discontinued. An upgradient control electrode not exposed to acetate produced low, steady currents ({<=}0.2 mA/m{sup 2}). Elevated current was strongly correlated with uranium removal but minimal correlation existed with elevated Fe(II). Confocal laser scanning microscopy of electrodes revealed firmly attached biofilms, and analysis of 16S rRNA gene sequences indicated the electrode surfaces were dominated (67-80%) by Geobacter species. This is the first demonstration that electrodes can produce readily detectable currents despite long-range (6 m) separation of anode and cathode, and these results suggest that oxidation of acetate coupled to electron transfer to electrodes by Geobacter species was the primary source of current. Thus it is expected that current production may serve as an effective proxy for monitoring in situ microbial activity in a variety of subsurface anoxic environments.

  15. The Mojave vadose zone: a subsurface biosphere analogue for Mars.

    Science.gov (United States)

    Abbey, William; Salas, Everett; Bhartia, Rohit; Beegle, Luther W

    2013-07-01

    If life ever evolved on the surface of Mars, it is unlikely that it would still survive there today, but as Mars evolved from a wet planet to an arid one, the subsurface environment may have presented a refuge from increasingly hostile surface conditions. Since the last glacial maximum, the Mojave Desert has experienced a similar shift from a wet to a dry environment, giving us the opportunity to study here on Earth how subsurface ecosystems in an arid environment adapt to increasingly barren surface conditions. In this paper, we advocate studying the vadose zone ecosystem of the Mojave Desert as an analogue for possible subsurface biospheres on Mars. We also describe several examples of Mars-like terrain found in the Mojave region and discuss ecological insights that might be gained by a thorough examination of the vadose zone in these specific terrains. Examples described include distributary fans (deltas, alluvial fans, etc.), paleosols overlain by basaltic lava flows, and evaporite deposits.

  16. Visualizing subsurface defects in graphite by acoustic atomic force microscopy.

    Science.gov (United States)

    Wang, Tian; Ma, Chengfu; Hu, Wei; Chen, Yuhang; Chu, Jiaru

    2017-01-01

    We describe a versatile platform, which combines atomic force acoustic microscopy, ultrasonic atomic force microscopy and heterodyne force microscopy. The AFM system can enable in-situ switching among these operation modes flexibly and thus benefit the discrimination of differences in mechanical properties and buried subsurface nanostructures. We demonstrate the potential of this platform for visualizing the subsurface defects of graphite. Our results show that tiny topographic edges are enhanced in acoustic oscillation signals whilst embedded defects and inhomogeneous in mechanical properties are made clearly distinguishable. The possibility of detecting subsurface defects in few-layer graphene is further discussed with first-principles calculations. Microsc. Res. Tech. 80:66-74, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. Interactive directional subsurface scattering and transport of emergent light

    DEFF Research Database (Denmark)

    Dal Corso, Alessandro; Frisvad, Jeppe Revall; Mosegaard, Jesper

    2016-01-01

    need to store elements of irradiance from specific directions. To include changes in subsurface scattering due to changes in the direction of the incident light, we instead sample incident radiance and store scattered radiosity. This enables us to accommodate not only the common distance......-based analytical models for subsurface scattering but also directional models. In addition, our method enables easy extraction of virtual point lights for transporting emergent light to the rest of the scene. Our method requires neither preprocessing nor texture parameterization of the translucent objects....... To build our maps of scattered radiosity, we progressively render the model from different directions using an importance sampling pattern based on the optical properties of the material. We obtain interactive frame rates, our subsurface scattering results are close to ground truth, and our technique...

  18. DETERMINATION OF IMPORTANCE EVALUATION FOR THE SUBSURFACE EXPORATORY STUDIES FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    W.J. Clark

    1999-06-28

    This Determination of Importance Evaluation (DIE) applies to the Subsurface Exploratory Studies Facility (ESF), encompassing the Topopah Spring (TS) Loop from Station 0+00 meters (m) at the North Portal to breakthrough at the South Portal (approximately 78+77 m), the Enhanced Characterization of the Repository Block (ECRB) East-West Cross Drift Starter Tunnel (to approximate ECRB Station 0+26 m), and ancillary test and operation support areas in the TS Loop. This evaluation applies to the construction, operation, and maintenance of these excavations. A more detailed description of these items is provided in Section 6.0. Testing activities are not evaluated in this DIE. Certain construction activities with respect to testing activities are evaluated; but the testing activities themselves are not evaluated. The DIE for ESF Subsurface Testing Activities (BAJ3000000-01717-2200-00011 Rev 01) (CRWMS M&O 1998a) evaluates Subsurface ESF Testing activities. The construction, operation, and maintenance of the TS Loop niches and alcove slot cuts is evaluated herein and is also discussed in CRWMS M&O 1998a. The construction, operation, and maintenance of the Busted Butte subsurface test area in support of the Unsaturated Zone (UZ) Transport Test is evaluated in CRWMS M&O 1998a. Potential test-to-test interference and the waste isolation impacts of testing activities are evaluated in the ESF Subsurface Testing Activities DIE and other applicable evaluation(s) for the Job Package (JP), Test Planning Package (TPP), and/or Field Work Package (FWP). The objectives of this DIE are to determine whether the Subsurface ESF TS Loop and associated excavations, including activities associated with their construction and operation, potentially impact site characterization testing or the waste isolation capabilities of the site. Controls needed to limit any potential impacts are identified. The validity and veracity of the individual tests, including data collection, are the responsibility

  19. Subsurface Event Detection and Classification Using Wireless Signal Networks

    Directory of Open Access Journals (Sweden)

    Muhannad T. Suleiman

    2012-11-01

    Full Text Available Subsurface environment sensing and monitoring applications such as detection of water intrusion or a landslide, which could significantly change the physical properties of the host soil, can be accomplished using a novel concept, Wireless Signal Networks (WSiNs. The wireless signal networks take advantage of the variations of radio signal strength on the distributed underground sensor nodes of WSiNs to monitor and characterize the sensed area. To characterize subsurface environments for event detection and classification, this paper provides a detailed list and experimental data of soil properties on how radio propagation is affected by soil properties in subsurface communication environments. Experiments demonstrated that calibrated wireless signal strength variations can be used as indicators to sense changes in the subsurface environment. The concept of WSiNs for the subsurface event detection is evaluated with applications such as detection of water intrusion, relative density change, and relative motion using actual underground sensor nodes. To classify geo-events using the measured signal strength as a main indicator of geo-events, we propose a window-based minimum distance classifier based on Bayesian decision theory. The window-based classifier for wireless signal networks has two steps: event detection and event classification. With the event detection, the window-based classifier classifies geo-events on the event occurring regions that are called a classification window. The proposed window-based classification method is evaluated with a water leakage experiment in which the data has been measured in laboratory experiments. In these experiments, the proposed detection and classification method based on wireless signal network can detect and classify subsurface events.

  20. Subsurface temperatures in Denmark – measurements and modelling

    DEFF Research Database (Denmark)

    Balling, N.; Poulsen, Søren Erbs; Bording, Thue Sylvester

    Information of subsurface temperature distribution in the Danish area originates from direct measurements in boreholes and from indirect theoretical modelling. “Point observations” of varying quality are available as industrially measured “Bottom Hole Temperatures” from deep exploration boreholes......, and accurate continuous equilibrium temperature logging has been carried out in a number of accessible deep boreholes. A regional distribution of subsurface temperatures is obtained by combining measurements and 3D numerical modelling in which the heat equation is solved. Modelling results are constrained...

  1. Subsurface Contamination Focus Area technical requirements. Volume 1: Requirements summary

    Energy Technology Data Exchange (ETDEWEB)

    Nickelson, D.; Nonte, J.; Richardson, J.

    1996-10-01

    This document summarizes functions and requirements for remediation of source term and plume sites identified by the Subsurface Contamination Focus Area. Included are detailed requirements and supporting information for source term and plume containment, stabilization, retrieval, and selective retrieval remedial activities. This information will be useful both to the decision-makers within the Subsurface Contamination Focus Area (SCFA) and to the technology providers who are developing and demonstrating technologies and systems. Requirements are often expressed as graphs or charts, which reflect the site-specific nature of the functions that must be performed. Many of the tradeoff studies associated with cost savings are identified in the text.

  2. Subsurface In Situ Elemental Composition Measurements with PING

    Science.gov (United States)

    Parsons, Ann; McClanahan, Timothy; Bodnarik, Julia; Evans, Larry; Nowicki, Suzanne; Schweitzer, Jeffrey; Starr, Richard

    2013-01-01

    This paper describes the Probing In situ with Neutron and Gamma rays (PING) instrument, that can measure the subsurface elemental composition in situ for any rocky body in the solar system without the need for digging into the surface. PING consists of a Pulsed Neutron Generator (PNG), a gamma ray spectrometer and neutron detectors. Subsurface elements are stimulated by high-energy neutrons to emit gamma rays at characteristic energies. This paper will show how the detection of these gamma rays results in a measurement of elemental composition. Examples of the basalt to granite ratios for aluminum and silicon abundance are provided.

  3. Evaluation of nutrient removal efficiency and microbial enzyme activity in a baffled subsurface-flow constructed wetland system

    Science.gov (United States)

    Lihua Cui; Ying Ouyang; Wenjie Gu; Weozhi Yang; Qiaoling. Xu

    2013-01-01

    In this study, the enzyme activities and their relationships to domestic wastewater purification are investigated in four different types of subsurface-flow constructed wetlands (CWs), namely the traditional horizontal subsurface-flow, horizontal baffled subsurface-flow, vertical baffled subsurface-flow, and composite baffled subsurface-flow CWs. Results showed that...

  4. Subsurface ecosystem resilience: long-term attenuation of subsurface contaminants supports a dynamic microbial community

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, J.M.; Neuhauser, E.F.; Ripp, J.A.; Mauro, D.M.; Madsen, E.L. [Cornell University, Ithaca, NY (United States). Dept. of Microbiology

    2010-01-15

    The propensity for groundwater ecosystems to recover from contamination by organic chemicals (in this case, coal-tar waste) is of vital concern for scientists and engineers who manage polluted sites. The microbially mediated cleanup processes are also of interest to ecologists because they are an important mechanism for the resilience of ecosystems. In this study we establish the long-term dynamic nature of a coal-tar waste-contaminated site and its microbial community. We present 16 years of chemical monitoring data, tracking responses of a groundwater ecosystem to organic contamination (naphthalene, xylenes, toluene, 2-methyl naphthalene and acenaphthylene) associated with coal-tar waste. In addition, we analyzed small-subunit (SSU) ribosomal RNA (rRNA) genes from two contaminated wells at multiple time points over a 2-year period. Principle component analysis of community rRNA fingerprints (terminal-restriction fragment length polymorphism (T-RFLP)) showed that the composition of native microbial communities varied temporally, yet remained distinctive from well to well. After screening and analysis of 1178 cloned SSU rRNA genes from Bacteria, Archaea and Eukarya, we discovered that the site supports a robust variety of eukaryotes (for example, alveolates (especially anaerobic and predatory ciliates), stramenopiles, fungi, even the small metazoan flatworm, Suomina) that are absent from an uncontaminated control well. This study links the dynamic microbial composition of a contaminated site with the long-term attenuation of its subsurface contaminants.

  5. The role of nanopores on U(VI) sorption and redox behavior in U(VI)-contaminated subsurface sediments

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Huifang; Roden, Eric E.; Kemner, Kenneth M.; Jung, Hun-Bok; Konishi, Hiromi; Boyanov, Maxim; Sun, Yubing; Mishra, Bhoopesh

    2013-10-16

    Most reactive surfaces in clay-dominated sediments are present within nanopores (pores of nm dimension). The behavior of geological fluids and minerals in nanopores is significantly different from those in normal non-nanoporous environments. The effect of nanopore surfaces on U(VI) sorption/desorption and reduction is likely to be significant in clay-rich subsurface environments. Our research results from both model nanopore system and natural sediments from both model system (synthetic nanopore alumina) and sediments from the ORNL Field Research Center prove that U(VI) sorption on nanopore surfaces can be greatly enhanced by nanopore confinement environments. The results from the project provide advanced mechanistic, quantitative information on the physiochemical controls on uranium sorption and redox behavior in subsurface sediments. The influence of nanopore surfaces on coupled uranium sorption/desorption and reduction processes is significant in virtually all subsurface environments, because most reactive surfaces are in fact nanopore surfaces. The results will enhance transfer of our laboratory-based research to a major field research initiative where reductive uranium immobilization is being investigated. Our results will also provide the basic science for developing in-situ colloidal barrier of nanoporous alumina in support of environmental remediation and long term stewardship of DOE sites.

  6. Martian sub-surface ionising radiation: biosignatures and geology

    Directory of Open Access Journals (Sweden)

    J. M. Ward

    2007-07-01

    Full Text Available The surface of Mars, unshielded by thick atmosphere or global magnetic field, is exposed to high levels of cosmic radiation. This ionising radiation field is deleterious to the survival of dormant cells or spores and the persistence of molecular biomarkers in the subsurface, and so its characterisation is of prime astrobiological interest. Here, we present modelling results of the absorbed radiation dose as a function of depth through the Martian subsurface, suitable for calculation of biomarker persistence. A second major implementation of this dose accumulation rate data is in application of the optically stimulated luminescence technique for dating Martian sediments.

    We present calculations of the dose-depth profile in the Martian subsurface for various scenarios: variations of surface composition (dry regolith, ice, layered permafrost, solar minimum and maximum conditions, locations of different elevation (Olympus Mons, Hellas basin, datum altitude, and increasing atmospheric thickness over geological history. We also model the changing composition of the subsurface radiation field with depth compared between Martian locations with different shielding material, determine the relative dose contributions from primaries of different energies, and discuss particle deflection by the crustal magnetic fields.

  7. Modelling near subsurface temperature with mixed type boundary ...

    Indian Academy of Sciences (India)

    geothermal data to extract both climate and groundwater flow signals. 1. Introduction. There is great interest to know past climate, especially to infer any anthropogenic signals in present climate by inter-comparison. The obser- vations of subsurface thermal regime in boreholes have been used to infer earth's thermal history.

  8. The significance of the subsurface in urban renewal

    NARCIS (Netherlands)

    Hooimeijer, F.L.; Maring, Linda

    2018-01-01

    The subsurface is a technical space, the “engine room of the city,” that incorporates the vital functions of water and energy supply, communication systems, sewers and drainage. Natural systems too – crucial for stable, dry, cool and nature inclusive cities – are also largely dependent on the

  9. Thermohaline features of the subsurface cyclonic eddy in the south ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 112; Issue 2. Thermohaline features of the subsurface cyclonic eddy in the south central Bay of Bengal during August 1999. P Madhusoodanan V V James. Volume 112 Issue 2 June 2003 pp 233-237 ...

  10. Subsurface ecosystems - Oil triggered life : Opportunities for the petroleum industry

    NARCIS (Netherlands)

    Van der Kraan, G.M.

    2010-01-01

    Areas of research - Petroleum microbiology: Determination of the microbial diversity of oil reservoirs and oil associated ecosystems (wellhead samples and oil field core samples). This research is performed to investigate if microbes can serve as indicators for changing conditions in subsurface

  11. Phylogenetic relationships among subsurface microorganisms. Project technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    Nierzwicki-Bauer, S.A.

    1993-08-01

    The development of group-specific, 16S ribosomal RNA-targeted oligonucleotide hybridization probes for the rapid detection of specific types of subsurface microorganisms is described. Because portions of the 16S RRNA molecule are unique to particular organisms or groups, these unique sequences can serve as targets for hybridization probes with varied specificity. Target sequences for selected microbial groups have been identified by analysis of the available RRNA sequence data for subsurface microbes. Hybridization probes for these target sequences were produced and their effectiveness and specificity tested with RNA cell blot and in situ hybridizations. Selected probes were used to study phylogenetic relationships among subsurface microbes and to classify these organisms into the specific groups that the probes are designed to detect. To date, this work has been performed on the P24 and C10 borehole isolates from the Savannah River Site. The probes will also be used, with in situ hybridizations, to detect and monitor selected microbial groups in freshly collected subsurface samples and laboratory microcosms in collaboration with other investigators. In situ hybridizations permit detection of selected microbial types without the necessity to isolate and culture them in the laboratory.

  12. Velocity profile and subsurface stratification in oil and gas ...

    African Journals Online (AJOL)

    With the use of pattern hole shots, there is the need for further investigation of the stratification of the subsurface structure in a particular field as near surface ... The results show that the consolidated region is mainly compact clay, sand stone, shale argillite and weathered fractured rocks which is indicative of possible ...

  13. Heteroepitaxial subsurface growth mode resulting in interlayer mixing

    DEFF Research Database (Denmark)

    Murray, P.W.; Thorshaug, S.; Stensgaard, I.

    1997-01-01

    A subsurface growth mode which results in interlayer mixing has been revealed from an interplay between scanning tunneling microscopy and ab initio total-energy calculations for the growth of Pd on Cu(110) and Ag(110) surfaces. On Cu(110), the Pd initially alloys into the surface layer forming...

  14. A Theoretical Study of Subsurface Drainage Model Simulation of ...

    African Journals Online (AJOL)

    A three-dimensional variable-density groundwater flow model, the SEAWAT model, was used to assess the influence of subsurface drain spacing, evapotranspiration and irrigation water quality on salt concentration at the base of the root zone, leaching and drainage in salt affected irrigated land. The study was carried out ...

  15. Application of sand and geotextile envelope in subsurface drip ...

    African Journals Online (AJOL)

    TUOYO

    2010-08-09

    Aug 9, 2010 ... Application of sand and geotextile envelope in subsurface drip irrigation. P. Najafi* and S. H. Tabatabaei. 1Islamic Azad University, Khorasgan Branch, P.O. 81595-158, Isfahan, Iran. 2Department of Water Engineering, Faculty of Agriculture, Shahrekord University, Shahrekord, Iran. Accepted 7 June, 2010.

  16. Pollutant removal in subsurface wastewater infiltration systems with ...

    African Journals Online (AJOL)

    Organic pollutant and nitrogen removal performance of subsurface wastewater infiltration systems (SWISs) with and without intermittent aeration, and operated under different organic pollutant loadings, was investigated. The intermittent aeration strategy not only significantly increased removal rates of organic pollutants and ...

  17. Adaptive Multiscale Finite Element Method for Subsurface Flow Simulation

    NARCIS (Netherlands)

    Van Esch, J.M.

    2010-01-01

    Natural geological formations generally show multiscale structural and functional heterogeneity evolving over many orders of magnitude in space and time. In subsurface hydrological simulations the geological model focuses on the structural hierarchy of physical sub units and the flow model addresses

  18. Pedological criteria for estimating the importance of subsurface ...

    African Journals Online (AJOL)

    E horizons formed in soils by reduction and eluviation are considered to be an indicator of subsurface lateral flow (SLF) between the A and B horizons – a hydrological process important in generating streamflow. There is, however, uncertainty in the interpretation of the hydropedological behaviour of some E horizons.

  19. Quantitative subsurface analysis using frequency modulated thermal wave imaging

    Science.gov (United States)

    Subhani, S. K.; Suresh, B.; Ghali, V. S.

    2018-01-01

    Quantitative depth analysis of the anomaly with an enhanced depth resolution is a challenging task towards the estimation of depth of the subsurface anomaly using thermography. Frequency modulated thermal wave imaging introduced earlier provides a complete depth scanning of the object by stimulating it with a suitable band of frequencies and further analyzing the subsequent thermal response using a suitable post processing approach to resolve subsurface details. But conventional Fourier transform based methods used for post processing unscramble the frequencies with a limited frequency resolution and contribute for a finite depth resolution. Spectral zooming provided by chirp z transform facilitates enhanced frequency resolution which can further improves the depth resolution to axially explore finest subsurface features. Quantitative depth analysis with this augmented depth resolution is proposed to provide a closest estimate to the actual depth of subsurface anomaly. This manuscript experimentally validates this enhanced depth resolution using non stationary thermal wave imaging and offers an ever first and unique solution for quantitative depth estimation in frequency modulated thermal wave imaging.

  20. Subsurface probe and hydrochemical analysis for the purpose of ...

    African Journals Online (AJOL)

    This paper deals with the probing of the subsurface by electrical resistivity method and hydrochemical analysis for the purpose of siting waste landfill. The landfill design made provision for secured containment of the segregated waste and associated leachate from man and industrial activities. The waste types that are ...

  1. Horizontal subsurface flow constructed wetlands for mitigation of ...

    African Journals Online (AJOL)

    The feasibility of using constructed wetlands (CWs) for the mitigation of pesticide runoff has been studied in the last decade. However, a lack of related data was verified when subsurface flow constructed wetlands (SSF CWs) are considered for this purpose. In the present work, SSF CWs were submitted to continuous ...

  2. A Theoretical Study of Subsurface Drainage Model Simulation of ...

    African Journals Online (AJOL)

    User

    Abstract. A three-dimensional variable-density groundwater flow model, the SEAWAT model, was used to assess the influence of subsurface drain spacing, ... that is appropriate for groundwater of variable density (Bear, 1997; Evans ...... the effects of salinity and climate change on crop plants. Horti. Sci. 78: 159–174.

  3. Subsurface ice structure analysis with longer wavelength sar tomography

    DEFF Research Database (Denmark)

    Banda, Francesco; Dall, Jørgen; Tebaldini, Stefano

    2013-01-01

    of longer wavelength SAR to retrieve information about ice flow and structure. In the present paper first results from processing of tomographic data for subsurface ice structure mapping are presented. The extent of signal penetration has been found to be of about 20-60 m, conditional on the different...

  4. subsurface sequence delineation and saline water mapping of lagos ...

    African Journals Online (AJOL)

    A subsurface sequence delineation and saline water mapping of Lagos State was carried out. Ten (10) deep boreholes with average depth of 300 m were drilled within the sedimentary basin. The boreholes were lithologically and geophysically logged. The driller's lithological logs aided by gamma and resistivity logs, ...

  5. Evaluation of the Dutch subsurface geoportal: What lies beneath?

    NARCIS (Netherlands)

    Lance, K.T.; Georgiadou, Y.; Bregt, A.K.

    2011-01-01

    This paper focuses on a geoportal from a “what lies beneath” perspective. It analyses processes of budgeting, planning, monitoring, performance measurement, and reporting of the national initiative titled Digital Information of the Dutch Subsurface (known by its Dutch acronym, DINO). The study is

  6. Nematoda from the terrestrial deep subsurface of South Africa

    NARCIS (Netherlands)

    Borgonie, G.; García-Moyano, A.; Litthauer, D.; Bert, W.; Bester, A.; Heerden, van E.; Möller, C.; Erasmus, M.; Onstott, T.C.

    2011-01-01

    Since its discovery over two decades ago, the deep subsurface biosphere has been considered to be the realm of single-cell organisms, extending over three kilometres into the Earth’s crust and comprising a significant fraction of the global biosphere1–4. The constraints of temperature, energy,

  7. Heating subsurface formations by oxidizing fuel on a fuel carrier

    Energy Technology Data Exchange (ETDEWEB)

    Costello, Michael; Vinegar, Harold J.

    2012-10-02

    A method of heating a portion of a subsurface formation includes drawing fuel on a fuel carrier through an opening formed in the formation. Oxidant is supplied to the fuel at one or more locations in the opening. The fuel is combusted with the oxidant to provide heat to the formation.

  8. Use of dewatered sludge as microbial inoculum of a subsurface ...

    African Journals Online (AJOL)

    Brown earth–based subsurface wastewater infiltration systems (SWISs) inoculated with/without dewatered sludge were constructed and operated under the same conditions to boost the application of SWIS in brown soil areas. Start-up period of SWIS with dewatered sludge was 28 days, 12 days shorter than that of SWIS ...

  9. Online monitoring of food processes using subsurface laser scattering

    DEFF Research Database (Denmark)

    Carstensen, Jens Michael; Møller, Flemming

    Online monitoring of physical parameters during food production is not a trivial task, but promising results can often be obtained with Subsurface Laser Scattering (SLS). The first SLS instruments are on the market today, and studies are needed to asses the potential of the technology. SLS can...

  10. Feasibility study of tank leakage mitigation using subsurface barriers

    Energy Technology Data Exchange (ETDEWEB)

    Treat, R.L.; Peters, B.B.; Cameron, R.J.; McCormak, W.D.; Trenkler, T.; Walters, M.F. [Ensearch Environmental, Inc. (United States); Rouse, J.K.; McLaughlin, T.J. [Bovay Northwest, Inc., Richland, WA (United States); Cruse, J.M. [Westinghouse Hanford Co., Richland, WA (United States)

    1994-09-21

    The US Department of Energy (DOE) has established the Tank Waste Remediation System (TWRS) to satisfy manage and dispose of the waste currently stored in the underground storage tanks. The retrieval element of TWRS includes a work scope to develop subsurface impermeable barriers beneath SSTs. The barriers could serve as a means to contain leakage that may result from waste retrieval operations and could also support site closure activities by facilitating cleanup. Three types of subsurface barrier systems have emerged for further consideration: (1) chemical grout, (2) freeze walls, and (3) desiccant, represented in this feasibility study as a circulating air barrier. This report contains analyses of the costs and relative risks associated with combinations retrieval technologies and barrier technologies that from 14 alternatives. Eight of the alternatives include the use of subsurface barriers; the remaining six nonbarrier alternative are included in order to compare the costs, relative risks and other values of retrieval with subsurface barriers. Each alternative includes various combinations of technologies that can impact the risks associated with future contamination of the groundwater beneath the Hanford Site to varying degrees. Other potential risks associated with these alternatives, such as those related to accidents and airborne contamination resulting from retrieval and barrier emplacement operations, are not quantitatively evaluated in this report.

  11. Treatment of swine wastewater with subsurface-flow constructed ...

    African Journals Online (AJOL)

    This study evaluates the capability of horizontal subsurface-flow constructed wetlands (SSF CWs) for treating pretreated swine wastewater as a function of contact time (CT) and type of macrophyte under the local conditions of Yucatán, Mexico. Experiments were conducted from July 2004 to November 2005 on a ...

  12. Uranium Biomineralization by Natural Microbial Phosphatase Activities in the Subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Sobecky, Patricia A. [Univ. of Alabama, Tuscaloosa, AL (United States)

    2015-04-06

    In this project, inter-disciplinary research activities were conducted in collaboration among investigators at The University of Alabama (UA), Georgia Institute of Technology (GT), Lawrence Berkeley National Laboratory (LBNL), Brookhaven National Laboratory (BNL), the DOE Joint Genome Institute (JGI), and the Stanford Synchrotron Radiation Light source (SSRL) to: (i) confirm that phosphatase activities of subsurface bacteria in Area 2 and 3 from the Oak Ridge Field Research Center result in solid U-phosphate precipitation in aerobic and anaerobic conditions; (ii) investigate the eventual competition between uranium biomineralization via U-phosphate precipitation and uranium bioreduction; (iii) determine subsurface microbial community structure changes of Area 2 soils following organophosphate amendments; (iv) obtain the complete genome sequences of the Rahnella sp. Y9-602 and the type-strain Rahnella aquatilis ATCC 33071 isolated from these soils; (v) determine if polyphosphate accumulation and phytate hydrolysis can be used to promote U(VI) biomineralization in subsurface sediments; (vi) characterize the effect of uranium on phytate hydrolysis by a new microorganism isolated from uranium-contaminated sediments; (vii) utilize positron-emission tomography to label and track metabolically-active bacteria in soil columns, and (viii) study the stability of the uranium phosphate mineral product. Microarray analyses and mineral precipitation characterizations were conducted in collaboration with DOE SBR-funded investigators at LBNL. Thus, microbial phosphorus metabolism has been shown to have a contributing role to uranium immobilization in the subsurface.

  13. Warm season performance of horizontal subsurface flow constructed ...

    African Journals Online (AJOL)

    Warm season performance of horizontal subsurface flow constructed wetlands vegetated with rice treating water from an urban stream polluted with sewage. ... Constructed wetlands demonstrated a very good performance in removing organic matter, fecal indicator microorganisms and nutrients from the influent ...

  14. Monitoring subsurface coal fires in Jharia coalfield using ...

    Indian Academy of Sciences (India)

    In this study, Differential Interferometric Synthetic Aperature Radar (DInSAR) technique has been utilized to monitor subsurface coal fires in the Jharia coalfield. Results showed that majority of the coal fire-related subsidence were concentrated on the eastern and western boundaries of the coalfield. The magnitude of ...

  15. Geoelectric Investigation of Subsurface Structure of Academic Area ...

    African Journals Online (AJOL)

    Geoelectric Investigation of Subsurface Structure of Academic Area of the Old Campus of Bayero University Kano for Optimized Citing of Boreholes. ... The study identified the areas between Biology Department and Central Mosque, and around Sports Complex for groundwater exploitation activities. Keywords: Apparent ...

  16. Yield response and economics of shallow subsurface drip irrigation systems

    Science.gov (United States)

    Field tests were conducted using shallow subsurface drip irrigation (S3DI) on cotton (Gossypium hirsutum, L.), corn (Zea mays, L.), and peanut (Arachis hypogeae, L.) in rotation to investigate yield potential and economic sustainability of this irrigation system technique over a six year period. Dri...

  17. Pressure and fluid dynamic characterisation of the Dutch subsurface

    NARCIS (Netherlands)

    Verweij, J.M.; Simmelink, H.J.; Underschultz, J.; Witmans, N.

    2012-01-01

    This paper presents and discusses the distribution of fluid and leak-off pressure data from the subsurface of onshore and offshore Netherlands in relation to causes of formation fluid overpressure and the permeability framework. The observed fluid pressure conditions demonstrate a clear regional

  18. Variability of surface and subsurface properties of an ultisol as ...

    African Journals Online (AJOL)

    Variability of surface and subsurface properties of an ultisol as function of topography in Sandstone landscape of Southwestern Nigeria. GA Oluwatosin. Abstract. No Abstract. Global Journal of Pure and Applied Sciences Vol. 13 (1) 2007: pp. 27-34. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT ...

  19. Subsurface analysis of semiconductor structures with helium ion microscopy

    NARCIS (Netherlands)

    van Gastel, Raoul; Hlawacek, G.; Zandvliet, Henricus J.W.; Poelsema, Bene

    2012-01-01

    We have used helium ion microscopy to directly track the subsurface diffusion of Pd through a Si stack in a non-invasive manner. The imaging and analysis of semiconductor structures along a direction perpendicular to the substrate is traditionally performed by making cross sections of a sample and

  20. Assessment of Subsurface Conditions in a Coastal Area of Lagos ...

    African Journals Online (AJOL)

    An integrated geophysical and geotechnical survey was carried out at Magodo Estate, Lagos, Nigeria. The buildings in this area are either sinking or intensively affected by severe cracks showing structural instability. The survey was aimed at characterizing the shallow subsurface in order to delineate features that may have ...

  1. Two dimentional modeling of subsurface structure over upper Benue ...

    African Journals Online (AJOL)

    A two dimensional modelling of the subsurface structures of parts of Benue Trough and Bornu Basin, northeast Nigeria, using aeromagnetic data was carried out in this study. The area under investigation is bounded by latitude 9.50 N to 12.00 N and longitude 9.50 E to 12.00 E. It is covered by 25 aeromagnetic maps.

  2. Application of sand and geotextile envelope in subsurface drip ...

    African Journals Online (AJOL)

    Subsurface drip irrigation is a technology used for better management of irrigation water. This technique is more desirable in arid and semi-arid region, because of decreasing soil surface evaporation and more efficiency of irrigation system in comparison with the other irrigation systems. Inaddition, this system is a safer way ...

  3. The potential of imaging subsurface heterogeneities by local, natural earthquakes

    NARCIS (Netherlands)

    Nishitsuji, Y.; Doi, I.; Draganov, D.S.

    2014-01-01

    We have developed a new imaging technique of subsurface heterogeneities that uses Sp-waves from natural earthquakes. This technique can be used as a first screening tool in frontier exploration areas before conventional active exploration. Analyzing Sp-waves from 28 earthquakes (Mj 2.0 to 4.2)

  4. Assessment of Subsurface Conditions in a Coastal Area of Lagos ...

    African Journals Online (AJOL)

    Akorede

    construction in civil engineering (Soupios, et al, 2007). Engineering ... geophysical methods to investigate the subsurface setting of the area. ..... International. Journal of Energy Science and Engineering, 1 (2): 40 -48. Coker, S. J., Ejedawe, J. E. and Oshiorienua (1983). Hydrocarbon source potentials of Cretaceous rocks of.

  5. Subsurface Zoning For Urban Development Under For Different Geological Conditions

    Science.gov (United States)

    Mavlyanova, N. G.

    2015-12-01

    The main criteria for assessment of urban territory for sustainability for underground construction occurred at a certain depth of continuous soil and rock strata of permanent thickness high bearing capacity. Distinguishing areas depending on the distribution, depth of occurrence and thickness of such rock strata is the first stage of territory zoning according to the geological conditions favorable for subsurface construction. The hydrogeological conditions, as well as the development of natural and techno natural hazards, are assessed at the next stage. In this paper, the method and technique of compiling the map of subsurface zoning according to the geological conditions is discussed for two cities with difference geological conditions: Moscow (Russia) and Tashkent (Uzbekistan). Vertical zoning of cities subsurface is controlled by three basic levels: up to a depth of 10 m, foundations of the most of the buildings are situated; up to a depth of 20 m, the highway tunnels are located, collectors of deep subsurface communication lines, and foundations of large multi-purpose complexes; up to a depth of 40 m, deep highway tunnels are located, and foundations of individual unique buildings. In Moscow, the mid- and upper Jurassic clay layer and the Carboniferous carbonate-terrigenous complex are the most continuously stretching stratigraphic and lithological rock strata of permanent thickness. The location of modern and buried ancient erosional channels is one of the chief factors controlling the geological conditions in Moscow. The degree of territory favorable for subsurface construction depends on the depth of the thickness of the Jurassic clay horizon. Tashkent city is located in a high seismic zone and therefore the geological conditions of underground space are defined first by the modern tectonic movements and secondly is defined by distribution of loess soils with up to the depth of 70 m. Hydrogeology is important factor for sustainability of constructions.

  6. Subsurface Stress Fields in FCC Single Crystal Anisotropic Contacts

    Science.gov (United States)

    Arakere, Nagaraj K.; Knudsen, Erik; Swanson, Gregory R.; Duke, Gregory; Ham-Battista, Gilda

    2004-01-01

    Single crystal superalloy turbine blades used in high pressure turbomachinery are subject to conditions of high temperature, triaxial steady and alternating stresses, fretting stresses in the blade attachment and damper contact locations, and exposure to high-pressure hydrogen. The blades are also subjected to extreme variations in temperature during start-up and shutdown transients. The most prevalent high cycle fatigue (HCF) failure modes observed in these blades during operation include crystallographic crack initiation/propagation on octahedral planes, and non-crystallographic initiation with crystallographic growth. Numerous cases of crack initiation and crack propagation at the blade leading edge tip, blade attachment regions, and damper contact locations have been documented. Understanding crack initiation/propagation under mixed-mode loading conditions is critical for establishing a systematic procedure for evaluating HCF life of single crystal turbine blades. This paper presents analytical and numerical techniques for evaluating two and three dimensional subsurface stress fields in anisotropic contacts. The subsurface stress results are required for evaluating contact fatigue life at damper contacts and dovetail attachment regions in single crystal nickel-base superalloy turbine blades. An analytical procedure is presented for evaluating the subsurface stresses in the elastic half-space, based on the adaptation of a stress function method outlined by Lekhnitskii. Numerical results are presented for cylindrical and spherical anisotropic contacts, using finite element analysis (FEA). Effects of crystal orientation on stress response and fatigue life are examined. Obtaining accurate subsurface stress results for anisotropic single crystal contact problems require extremely refined three-dimensional (3-D) finite element grids, especially in the edge of contact region. Obtaining resolved shear stresses (RSS) on the principal slip planes also involves

  7. Radiolytic H2 Production on Noachian Mars: Implications for Subsurface Habitability

    Science.gov (United States)

    Tarnas, J. D.; Mustard, J. F.; Sherwood Lollar, B.; Bramble, M. S.; Cannon, K. M.; Palumbo, A. M.

    2017-10-01

    The amount of H2 produced on Noachian Mars via radiolysis could support a subsurface biosphere. Geophysical models constrain depth of the longest-lived subsurface habitat, from which biosignature-hosting material can be excavated by later impacts.

  8. Enamel subsurface lesion remineralisation with casein phosphopeptide stabilised solutions of calcium, phosphate and fluoride

    National Research Council Canada - National Science Library

    Cochrane, N J; Saranathan, S; Cai, F; Cross, K J; Reynolds, E C

    2008-01-01

    ...) solutions have been shown to remineralise enamel subsurface lesions. The aim of this study was to determine the effect of ion composition of CPP-ACP and CPP-ACFP solutions on enamel subsurface lesion remineralisation in vitro...

  9. Subsurface chlorophyll maxima in the north-western Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.; Aswanikumar, V.

    The depth profiles of phytoplankton pigments in the north-western Bay of Bengal are generally characterizEd. by a subsurface chlorophyll maximum. The occurrence of subsurface chlorophyll maxima is discussed in relation to other information on water...

  10. SUBSURFACE BARRIER VALIDATION WITH THE SEAFACE SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Sandra Dalvit Dunn

    1997-11-30

    construction of the facility to assure there would be no undesired leaks, the primary barrier to diffusion (a 30-mil high density polyethylene membrane) failed. The unanticipated leaks were large enough that tracer gas diffusing from them masked the designed leaks. The test facility was re-excavated and a new membrane installed. Initial tests of this barrier showed that it also leaked near the bottom of the barrier. However, careful control of the subsequent tracer gas injections, coupled with extensive data analysis to minimize the effects of the high background tracer gas concentrations, allowed leak characterization to be completed successfully. The proposed Phase II demonstration for this project is a double wall, jet grouted coffer dam at the Dover Air Force Base Groundwater Remediation Field Laboratory. This barrier will be constructed of multiple thin wall panels (nominally 6 to 10-inch thick) installed to form a vertical right circular cylinder, approximately 30 ft. in diameter. The barrier will be keyed into a clay layer at the 45 ft. depth, forming the bottom of the barrier.

  11. A technical investigation on tools and concepts for sustainable management of the subsurface in The Netherlands

    NARCIS (Netherlands)

    Griffioen, Jasper; van Wensem, Joke; Oomes, Justine L.M.; Barends, Frans; Breunese, Jaap; Bruining, Hans; Olsthoorn, Theo; Stams, Alfons J.M.; van der Stoel, Almer E.C.

    2014-01-01

    In response to increasing use of the subsurface, there is a need to modernise policies on sustainable use of the subsurface. This holds in particular for the densely populated Netherlands. We aimed to analyse current practice of subsurface management and the associated pressure points and to

  12. Integrated geomechanical modelling at TNO for assessement of deep subsurface risks

    NARCIS (Netherlands)

    Orlic, B.; Fokker, P.; Zijl, W.; Scheffers, B.

    2001-01-01

    Public authorities, E & P and the mining industry increasingly demand fundamental insight and accurate predictions on subsurface and surface deformation and damage due to exploitation of subsurface natural resources, and subsurface storage of energy residues (e.g. CO2). At this moment deformation is

  13. Colloid formation in groundwater by subsurface aeration: characterisation of the geo-colloids and their counterparts

    NARCIS (Netherlands)

    Wolthoorn, A.; Temminghoff, E.J.M.; Riemsdijk, van W.H.

    2004-01-01

    Subsurface aeration is used to oxidise Fe in situ in groundwater to make the water potable. In a groundwater system with pH > 7, subsurface aeration results in a non-mobile Fe precipitate and mobile Fe colloids. Since originally the goal of subsurface aeration is to remove Fe in situ, the

  14. Interaction of surface and subsurface waters in the system

    Science.gov (United States)

    Mazukhina, Svetlana; Masloboev, Vladimir; Chudnenko, Konstantin; Bychinski, Valerii; Sandimirov, Sergey

    2010-05-01

    Purpose of the study - to assess the influence of the Khibiny massif on the formation of the chemical composition of surface and subsurface waters, generated within its boundaries using physical-chemical modeling ("Selector" software package). Objects of monitoring - rivers with sources in the upper reaches of the Khibiny massif (surface waters), and boreholes, located in these rivers' valleys (subsurface waters) have been chosen as objects of monitoring. Processes of formation of surface and subsurface waters, generated within the boundaries of the Khibiny massif, have been considered within the framework of a unified system "water-rock-atmosphere-carbon". The initial data of the model: chemical compositions of the Khibiny massif rocks and chemical analyses of atmospheric and surface waters. Besides, there have been considered Clarke concentrations S, Cl, F, C, their influence on the formation of chemical composition of water solutions; geochemical mobility of chemical elements. The previously developed model has been improved with the purpose of assessment of the influence of organic substance, either liquid or solid, on the formation of the chemical composition of water. The record of the base model of the multisystem includes 24 independent components (Al-B-Br-Ar-He-Ne-C-Ca-Cl-F-K-Mg-Mn-N-Na-P-S-Si-Sr-Cu-Zn-H-O-e), 872 dependent components, including, in a water solution - 295, in a gas phase - 76, liquid hydrocarbons - 111, solid phases, organic and mineral substances - 390. The record of solid phases of multisystem is made with consideration of the mineral composition of the Khibiny massif. Using the created model, the physical-chemical modeling of surface and subsurface water generation has been carried out: 1. The system "water-rock-atmosphere" has been studied, depending on the interaction degree (ksi) of rock with water. A model like this allowed investigating the interactions of surface waters (rivers and lakes) with rocks that form the Khibiny massif. 2

  15. Distribution and activity of hydrogenase enzymes in subsurface sediments

    Science.gov (United States)

    Adhikari, R.; Nickel, J.; Glombitza, C.; Spivack, A. J.; D'Hondt, S. L.; Kallmeyer, J.

    2013-12-01

    Metabolically active microbial communities are present in a wide range of subsurface environments. Techniques like enumeration of microbial cells, activity measurements with radiotracer assays and the analysis of porewater constituents are currently being used to explore the subsurface biosphere, alongside with molecular biological analyses. However, many of these techniques reach their detection limits due to low microbial activity and abundance. Direct measurements of microbial turnover not just face issues of insufficient sensitivity, they only provide information about a single specific process rather than an overall microbial activity. Since hydrogenase enzymes are intracellular and ubiquitous in subsurface microbial communities, the enzyme activity represents a measure of total activity of the entire microbial community. A hydrogenase activity assay could quantify total metabolic activity without having to identify specific processes. This would be a major advantage in subsurface biosphere studies, where several metabolic processes can occur simultaneously. We quantified hydrogenase enzyme activity and distribution in sediment samples from different aquatic subsurface environments (Lake Van, Barents Sea, Equatorial Pacific and Gulf of Mexico) using a tritium-based assay. We found enzyme activity at all sites and depths. Volumetric hydrogenase activity did not show much variability between sites and sampling depths, whereas cell-specific activity ranged from 10-5 to 1 nmol H2 cell-1 d-1. Activity was lowest in sediment layers where nitrate was detected. Higher activity was associated with samples in which sulfate was the predominant electron acceptor. We found highest activity in samples from environments with >10 ppm methane in the pore water. The results show that cell-specific hydrogenase enzyme activity increases with decreasing energy yield of the electron acceptor used. It is not possible to convert volumetric or cell-specific hydrogenase activity into a

  16. Quantifying microbial activity in deep subsurface sediments using a tritium based hydrognease enzyme assay

    Science.gov (United States)

    Adhikari, R.; Nickel, J.; Kallmeyer, J.

    2012-12-01

    Microbial life is widespread in Earth's subsurface and estimated to represent a significant fraction of Earth's total living biomass. However, very little is known about subsurface microbial activity and its fundamental role in biogeochemical cycles of carbon and other biologically important elements. Hydrogen is one of the most important elements in subsurface anaerobic microbial metabolism. Heterotrophic and chemoautotrophic microorganisms use hydrogen in their metabolic pathways. They either consume or produce protons for ATP synthesis. Hydrogenase (H2ase) is a ubiquitous intracellular enzyme that catalyzes the interconversion of molecular hydrogen and/or water into protons and electrons. The protons are used for the synthesis of ATP, thereby coupling energy generating metabolic processes to electron acceptors such as CO2 or sulfate. H2ase enzyme targets a key metabolic compound in cellular metabolism therefore the assay can be used as a measure for total microbial activity without the need to identify any specific metabolic process. Using the highly sensitive tritium assay we measured H2ase enzyme activity in the organic-rich sediments of Lake Van, a saline, alkaline lake in eastern Turkey, in marine sediments of the Barents Sea and in deep subseafloor sediments from the Nankai Trough. H2ase activity could be quantified at all depths of all sites but the activity distribution varied widely with depth and between sites. At the Lake Van sites H2ase activity ranged from ca. 20 mmol H2 cm-3d-1 close to the sediment-water interface to 0.5 mmol H2 cm-3d-1 at a depth of 0.8 m. In samples from the Barents Sea H2ase activity ranged between 0.1 to 2.5 mmol H2 cm-3d-1 down to a depth of 1.60 m. At all sites the sulfate reduction rate profile followed the upper part of the H2ase activity profile until sulfate reduction reached the minimum detection limit (ca. 10 pmol cm-3d-1). H2ase activity could still be quantified after the decline of sulfate reduction, indicating that

  17. The subsurface record for the Anthropocene based on the global analysis of deep wells

    Science.gov (United States)

    Rose, K.

    2016-12-01

    While challenges persist in the characterization of Earth's subsurface, over two centuries of exploration resulting in more than six million deep wellbores, offer insights into these systems. Characteristics of the subsurface vary and can be analyzed on a variety of spatial scales using geospatial tools and methods. Characterization and prediction of subsurface properties, such as depth, thickness, porosity, permeability, pressure and temperature, are important for models and interpretations of the subsurface. Subsurface studies contribute to insights and understanding of natural system but also enable predictions and assessments of subsurface resources and support environmental and geohazard assessments. As the geo-data science landscape shifts, becoming more open, there are increasing opportunities to fill knowledge gaps, mine large, interrelated datasets, and develop innovative methods to improve our understanding of the subsurface and the impacts of its exploration. In this study, a global dataset of more than 6,000,000 deep subsurface wells has been assembled using ArcGIS and Access, which reflects to a first order, the cumulative representation of over two centuries of drilling. Wellbore data, in general represent the only portal for direct measurement and characterization of deep subsurface properties. As human engineering of the subsurface evolves from a focus on hydrocarbon resource development to include subsurface waste product disposal (e.g. CO2, industrial waste, etc) and production of other deep subsurface resources, such as heat and water resources, there is the increasing need to improve characterization techniques and understand local and global ramifications of anthropogenic interaction with the subsurface. Data and geospatial analyses are reviewed to constrain the extent to which human interactions, not just with Earth's surface systems, atmospheric and geologic, but subsurface systems will result in an enduring signature of human influences on

  18. Identifying and Managing Gas Leakage from Subsurface Sources

    Science.gov (United States)

    Benson, S. M.

    2015-12-01

    Subsurface gas accumulations exist from both natural sources such as hydrocarbon reservoirs, as well as, man-made sources such as natural gas storage, gas pipelines, CO2 storage, or even H2 storage. Both natural and manmade sources of subsurface gases have the potential to leak to the surface. Leakage can cause safety hazards and detrimental impacts associated with the release of greenhouse gases into the atmosphere. Leak management, which involves identifying, characterizing, assessing, and remediating leakage requires a coordinated and systematic approach to effectively deal with these occurrences. Here an overall workflow for leak management is presented, along with technological options and challenges for successful implementation. Many tools and approaches for leak management are available and in use today. However, the increased attention to leakage from a larger variety of sources, particularly associated with legacy facilities and infrastructure, raises new issues and challenges that are highlighted here.

  19. Automatic WEMVA by Focusing Subsurface Offset Virtual Sources

    KAUST Repository

    Sun, Bingbing

    2017-05-26

    Macro velocity building is important for subsequent prestack depth migration and full waveform inversion. Wave equation migration velocity analysis (WEMVA) utilizes band-limited waveform to invert the velocity in an automatic manner. Normally, inversion would be implemented by focusing the subsurface offset common image gathers(SOCIGs). We re-examine it with a different perspective and propose to view the SOCIGs and the background wavefield together as subsurface offset virtual sources(SOVS). A linear system connecting the perturbation of the position of those SOVS and velocity is derived and solved subsequently using a conjugate gradient method. Both synthetic and real dataset examples verify the correctness and effectiveness of the proposed method.

  20. Subsurface contrast due to friction in heterodyne force microscopy

    Science.gov (United States)

    Verbiest, G. J.; Oosterkamp, T. H.; Rost, M. J.

    2017-02-01

    The nondestructive imaging of subsurface structures on the nanometer scale has been a long-standing desire in both science and industry. A few impressive images were published so far that demonstrate the general feasibility by combining ultrasound with an atomic force microscope. From different excitation schemes, heterodyne force microscopy seems to be the most promising candidate delivering the highest contrast and resolution. However, the physical contrast mechanism is unknown, thereby preventing any quantitative analysis of samples. Here we show that friction at material boundaries within the sample is responsible for the contrast formation. This result is obtained by performing a full quantitative analysis, in which we compare our experimentally observed contrasts with simulations and calculations. Surprisingly, we can rule out all other generally believed responsible mechanisms, like Rayleigh scattering, sample (visco)elasticity, damping of the ultrasonic tip motion, and ultrasound attenuation. Our analytical description paves the way for quantitative subsurface-AFM imaging.

  1. Advanced Algebraic Multigrid Solvers for Subsurface Flow Simulation

    KAUST Repository

    Chen, Meng-Huo

    2015-09-13

    In this research we are particularly interested in extending the robustness of multigrid solvers to encounter complex systems related to subsurface reservoir applications for flow problems in porous media. In many cases, the step for solving the pressure filed in subsurface flow simulation becomes a bottleneck for the performance of the simulator. For solving large sparse linear system arising from MPFA discretization, we choose multigrid methods as the linear solver. The possible difficulties and issues will be addressed and the corresponding remedies will be studied. As the multigrid methods are used as the linear solver, the simulator can be parallelized (although not trivial) and the high-resolution simulation become feasible, the ultimately goal which we desire to achieve.

  2. Influence of groundwater composition on subsurface iron and arsenic removal

    KAUST Repository

    Moed, David H.

    2012-06-01

    Subsurface arsenic and iron removal (SAR/SIR) is a novel technology to remove arsenic, iron and other groundwater components by using the subsoil. This research project investigated the influence of the groundwater composition on subsurface treatment. In anoxic sand column experiments, with synthetic groundwater and virgin sand, it was found that several dissolved substances in groundwater compete for adsorption sites with arsenic and iron. The presence of 0.01 mmol L -1phosphate, 0.2 mmol L -1 silicate, and 1 mmol L -1 nitrate greatly reduced the efficiency of SAR, illustrating the vulnerability of this technology in diverse geochemical settings. SIR was not as sensitive to other inorganic groundwater compounds, though iron retardation was limited by 1.2 mmol L -1 calcium and 0.06 mmol L -1 manganese. © IWA Publishing 2012.

  3. Using electrical impedance tomography to map subsurface hydraulic conductivity

    Science.gov (United States)

    Berryman, James G.; Daily, William D.; Ramirez, Abelardo L.; Roberts, Jeffery J.

    2000-01-01

    The use of Electrical Impedance Tomography (EIT) to map subsurface hydraulic conductivity. EIT can be used to map hydraulic conductivity in the subsurface where measurements of both amplitude and phase are made. Hydraulic conductivity depends on at least two parameters: porosity and a length scale parameter. Electrical Resistance Tomography (ERT) measures and maps electrical conductivity (which can be related to porosity) in three dimensions. By introducing phase measurements along with amplitude, the desired additional measurement of a pertinent length scale can be achieved. Hydraulic conductivity controls the ability to flush unwanted fluid contaminants from the surface. Thus inexpensive maps of hydraulic conductivity would improve planning strategies for subsequent remediation efforts. Fluid permeability is also of importance for oil field exploitation and thus detailed knowledge of fluid permeability distribution in three-dimension (3-D) would be a great boon to petroleum reservoir analysts.

  4. Geomicrobiology and Metagenomics of Terrestrial Deep Subsurface Microbiomes.

    Science.gov (United States)

    Itävaara, M; Salavirta, H; Marjamaa, K; Ruskeeniemi, T

    2016-01-01

    Fractures in the deep subsurface of Earth's crust are inhabited by diverse microbial communities that participate in biogeochemical cycles of the Earth. Life on Earth, which arose c. 3.5-4.0 billion years ago, reaches down at least 5 km in the crust. Deep mines, caves, and boreholes have provided scientists with opportunities to sample deep subsurface microbiomes and to obtain information on the species diversity and functions. A wide variety of bacteria, archaea, eukaryotes, and viruses are now known to reside in the crust, but their functions are still largely unknown. The crust at different depths has varying geological composition and hosts endemic microbiomes accordingly. The diversity is driven by geological formations and gases evolving from deeper depths. Cooperation among different species is still mostly unexplored, but viruses are known to restrict density of bacterial and archaeal populations. Due to the complex growth requirements of the deep subsurface microbiomes, the new knowledge about their diversity and functions is mostly obtained by molecular methods, eg, meta'omics'. Geomicrobiology is a multidisciplinary research area combining disciplines from geology, mineralogy, geochemistry, and microbiology. Geomicrobiology is concerned with the interaction of microorganisms and geological processes. At the surface of mineralogical or rock surfaces, geomicrobial processes occur mainly under aerobic conditions. In the deep subsurface, however, the environmental conditions are reducing and anaerobic. The present chapter describes the world of microbiomes in deep terrestrial geological environments as well as metagenomic and metatranscriptomic methods suitable for studies of these enigmatic communities. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Martian geomorphology and its relation to subsurface volatiles

    Science.gov (United States)

    Clifford, Stephen M. (Editor); Rossbacher, Lisa A. (Editor); Zimbelman, James R. (Editor)

    1986-01-01

    Martian volatile inventory, planetary climatic and atmospheric evolution, and the interpretation of various remote sensing data were discussed. A number of morphologies that were cited as potential indicators of subsurface volatiles were reviewed. Rampart craters and terrain softening were the focus of more in-depth discussion because of the popular attention they have received and the fact that their areal distributions are by far the most extensive of all the proposed indicators.

  6. Method of sealing casings of subsurface materials management system

    Science.gov (United States)

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2007-02-06

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  7. Planetary subsurface investigation by 3D visualization model .

    Science.gov (United States)

    Seu, R.; Catallo, C.; Tragni, M.; Abbattista, C.; Cinquepalmi, L.

    Subsurface data analysis and visualization represents one of the main aspect in Planetary Observation (i.e. search for water or geological characterization). The data are collected by subsurface sounding radars as instruments on-board of deep space missions. These data are generally represented as 2D radargrams in the perspective of space track and z axes (perpendicular to the subsurface) but without direct correlation to other data acquisition or knowledge on the planet . In many case there are plenty of data from other sensors of the same mission, or other ones, with high continuity in time and in space and specially around the scientific sites of interest (i.e. candidate landing areas or particular scientific interesting sites). The 2D perspective is good to analyse single acquisitions and to perform detailed analysis on the returned echo but are quite useless to compare very large dataset as now are available on many planets and moons of solar system. The best way is to approach the analysis on 3D visualization model generated from the entire stack of data. First of all this approach allows to navigate the subsurface in all directions and analyses different sections and slices or moreover navigate the iso-surfaces respect to a value (or interval). The last one allows to isolate one or more iso-surfaces and remove, in the visualization mode, other data not interesting for the analysis; finally it helps to individuate the underground 3D bodies. Other aspect is the needs to link the on-ground data, as imaging, to the underground one by geographical and context field of view.

  8. Wireless Sensor Network Based Subsurface Contaminant Plume Monitoring

    Science.gov (United States)

    2012-04-16

    conventional WSN . VSN enabled closed loop system consumes more energy than the VSN only system, because of the commands that are send to the nodes. Energy ...predict future plume behavior. This proof-of-concept research aimed at demonstrating the use of an intelligent Wireless Sensor Network ( WSN ) to...Network ( WSN ) to monitor contaminant plume movement in naturally heterogeneous subsurface formations to advance the sensor networking based monitoring

  9. Vensis: Venus Advanced Radar For Subsurface And Ionosphere Sounding

    Science.gov (United States)

    Biccari, D.; Gurnett, D.; Jordan, R.; Huff, R.; Marinangeli, L.; Nielsen, E.; Ori, G. G.; Picardi, G.; Plaut, J.; Provvedi, F.; Seu, R.; Zampolini, E.

    Due to optically opaque atmosphere of Venus radar is the best way to observe the surface of the planet from orbit. Magellan has obtained global SAR imaging, as well as altimetry and emissivity. As a subsurface sounder, working at low frequency and preferably in the night time, VENSIS would obtain fundamentally different kinds of geologic information than Magellan, mapping of interfaces of geologic units (e.g. tessera, plains, lava flows, impact debris) could in fact be extended into the third di- mension. A subsurface investigation of the first 1-2 Km will show the internal defor- mations of the Venusian surface and will depict the structural styles of old crust which are essential to define the crust dynamics, an improved understanding of the evolu- tion of complex Venusian features is a key to define the geological evolution of the planet. Furthermore in standard subsurface sounding mode VENSIS will be able to transmit four different bandwidth, so the possibility of multi frequency observations will allow the estimate of the material attenuation in the crust and will give significant indications on the dielectric properties of the detected interfaces. Thus the Primary Scientific Objectives of VENSIS are the following: 1-Characterize surface roughness, composition and electrical properties at long wavelengths (orders of magnitude longer than Magellan) 2-Probe the subsurface of Venus (to few km depth) to detect and map geologic materials and large scale structures at planetary level VENSIS sounder, using active sounding in a frequency range of 100 kHz to 7 MHz, would also allow detailed characterization of the Venus ionosphere while in passive mode it can be used to detect lightning, the presence of which remains both controversial and critical to understand the behavior of the atmosphere and the possibility of present day volcanism. Therefore a secondary objective is to Probe the ionosphere to characterize interactions between the solar wind and the Venusian

  10. Uranium Biomineralization By Natural Microbial Phosphatase Activities in the Subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Taillefert, Martial [Georgia Tech Research Corporation, Atlanta, GA (United States)

    2015-04-01

    This project investigated the geochemical and microbial processes associated with the biomineralization of radionuclides in subsurface soils. During this study, it was determined that microbial communities from the Oak Ridge Field Research subsurface are able to express phosphatase activities that hydrolyze exogenous organophosphate compounds and result in the non-reductive bioimmobilization of U(VI) phosphate minerals in both aerobic and anaerobic conditions. The changes of the microbial community structure associated with the biomineralization of U(VI) was determined to identify the main organisms involved in the biomineralization process, and the complete genome of two isolates was sequenced. In addition, it was determined that both phytate, the main source of natural organophosphate compounds in natural environments, and polyphosphate accumulated in cells could also be hydrolyzed by native microbial population to liberate enough orthophosphate and precipitate uranium phosphate minerals. Finally, the minerals produced during this process are stable in low pH conditions or environments where the production of dissolved inorganic carbon is moderate. These findings suggest that the biomineralization of U(VI) phosphate minerals is an attractive bioremediation strategy to uranium bioreduction in low pH uranium-contaminated environments. These efforts support the goals of the SBR long-term performance measure by providing key information on "biological processes influencing the form and mobility of DOE contaminants in the subsurface".

  11. Subsurface metals fatigue cracking without and with crack tip

    Directory of Open Access Journals (Sweden)

    Andrey Shanyavskiy

    2013-07-01

    Full Text Available Very-High-Cycle-Fatigue regime for metals was considered and mechanisms of the subsurface crack origination were introduced. In many metals first step of crack origination takes place with specific area formation because of material pressing and rotation that directed to transition in any volume to material ultra-high-plasticity with nano-structure appearing. Then by the border of the nano-structure takes place volume rotation and fracture surface creates with spherical particles which usually named Fine-Granular-Area. In another case there takes place First-Smooth-Facet occurring in area of origin due to whirls appearing by the one of the slip systems under discussed the same stress-state conditions. Around Fine-Granular-Area or First-Smooth-Facet there plastic zone appeared and, then, subsurface cracking develops by the same manner as for through cracks. In was discussed quantum-mechanical nature of fatigue crack growth in accordance with Yang’s modulus quantization for low level of deformations. New simply equation was considered for describing subsurface cracking in metals out of Fine-Granular-Area or Fist-Smooth-Facet.

  12. Applications of electrical resistance tomography to subsurface environmental restoration

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, A.L. [Lawrence Livermore National Lab., CA (United States); Daily, W.D.

    1994-11-15

    We are developing a new imaging technique, Electrical Resistance Tomography (ERT), to map subsurface liquids as flow occurs during natural or clean-up processes and to map geologic structure. Natural processes (such as surface water infiltrating the vadose zone) and man-induced processes (such as tank leaks and clean-up processes such as steam injection), can create changes in a soil`s electrical properties that are readily measured. We have conducted laboratory and a variety of field experiments to investigate the capabilities and limitations of ERT for imaging underground structures and processes. In the last four years we have used ERT to successfully monitor several field processes including: a subsurface steam injection process (for VOC removal), an air injection process (below the water table) for VOC removal, water infiltration through the vadose zone, radio-frequency heating, ohmic heating, and tank and pond leaks. The information derived from ERT can be used by remediation projects to: detect and locate leaks, determine the effectiveness of clean-up processes, select appropriate clean-up alternatives, and to verify the installation and performance of subsurface barriers.

  13. Subsurface Biogeochemical Research FY11 Second Quarter Performance Measure

    Energy Technology Data Exchange (ETDEWEB)

    Scheibe, Timothy D.

    2011-03-31

    The Subsurface Biogeochemical Research (SBR) Long Term Measure for 2011 under the Performance Assessment Rating Tool (PART) measure is to "Refine subsurface transport models by developing computational methods to link important processes impacting contaminant transport at smaller scales to the field scale." The second quarter performance measure is to "Provide a report on computational methods linking genome-enabled understanding of microbial metabolism with reactive transport models to describe processes impacting contaminant transport in the subsurface." Microorganisms such as bacteria are by definition small (typically on the order of a micron in size), and their behavior is controlled by their local biogeochemical environment (typically within a single pore or a biofilm on a grain surface, on the order of tens of microns in size). However, their metabolic activity exerts strong influence on the transport and fate of groundwater contaminants of significant concern at DOE sites, in contaminant plumes with spatial extents of meters to kilometers. This report describes progress and key findings from research aimed at integrating models of microbial metabolism based on genomic information (small scale) with models of contaminant fate and transport in aquifers (field scale).

  14. Hydrogeological investigation of subsurface of Cukurkoy surroundings (Denizli

    Directory of Open Access Journals (Sweden)

    Suat TAŞDELEN

    2016-06-01

    Full Text Available Çukurköy graben, located at 13 km southeast from Denizli city, is a side basin with 96.4 km2 surface drainage area which is connected to the Gökpınar dam catchment area through narrow strait. There are a lots of resources having various discharges on the western slopes of the Honaz mountain in the east of the Çukurköy basin. These resources were originated from runoff from the ridges which is located between Tavas plain and Çukurköy basin, and were formed the Gökpınar creek, one of the main tributaries of Büyük Menderes river. In addition, subsurface waters feed these streams as leaks wherein groundwater level is very shallow level. By the time, local people had opened many boreholes and wells, and they caused to dry out of some continuous resources and streams. Discharge rates of scheduled pumping waters from boreholes are changing dramatically for short distances, because of irregularly located alluvial material. The flow direction of both shallow subsurface and surface waters of the basin outflows toward the northwest that is controlled by surface morphology. These shallow subsurface waters are insufficient for increasing requirements except for small and individual usages.

  15. Subsurface Stress Fields In Single Crystal (Anisotropic) Contacts

    Science.gov (United States)

    Arakere, Nagaraj K.; Knudsen, Erik C.; Duke, Greg; Battista, Gilda; Swanson, Greg

    2004-01-01

    Single crystal superalloy turbine blades used in high pressure turbomachinery are subject to conditions of high temperature, triaxial steady and alternating stresses, fretting stresses in the blade attachment and damper contact locations, and exposure to high-pressure hydrogen. The blades are also subjected to extreme variations in temperature during start-up and shutdown transients. The most prevalent HCF failure modes observed in these blades during operation include crystallographic crack initiation/propagation on octahedral planes, and noncrystallographic initiation with crystallographic growth. Numerous cases of crack initiation and crack propagation at the blade leading edge tip, blade attachment regions, and damper contact locations have been documented. Understanding crack initiation/propagation under mixed-mode loading conditions is critical for establishing a systematic procedure for evaluating HCF life of single crystal turbine blades. This paper presents analytical and numerical techniques for evaluating two and three dimensional subsurface stress fields in anisotropic contacts. The subsurface stress results are required for evaluating contact fatigue life at damper contacts and dovetail attachment regions in single crystal nickel-base superalloy turbine blades. An analytical procedure is , presented, for evaluating the subsurface stresses in the elastic half-space, using a complex potential method outlined by Lekhnitskii. Numerical results are presented for cylindrical and spherical anisotropic contacts, using finite element analysis. Effects of crystal orientation on stress response and fatigue life are examined.

  16. Differential subsidence and its effect on subsurface infrastructure: predicting probability of pipeline failure (STOOP project)

    Science.gov (United States)

    de Bruijn, Renée; Dabekaussen, Willem; Hijma, Marc; Wiersma, Ane; Abspoel-Bukman, Linda; Boeije, Remco; Courage, Wim; van der Geest, Johan; Hamburg, Marc; Harmsma, Edwin; Helmholt, Kristian; van den Heuvel, Frank; Kruse, Henk; Langius, Erik; Lazovik, Elena

    2017-04-01

    Due to heterogeneity of the subsurface in the delta environment of the Netherlands, differential subsidence over short distances results in tension and subsequent wear of subsurface infrastructure, such as water and gas pipelines. Due to uncertainties in the build-up of the subsurface, however, it is unknown where this problem is the most prominent. This is a problem for asset managers deciding when a pipeline needs replacement: damaged pipelines endanger security of supply and pose a significant threat to safety, yet premature replacement raises needless expenses. In both cases, costs - financial or other - are high. Therefore, an interdisciplinary research team of geotechnicians, geologists and Big Data engineers from research institutes TNO, Deltares and SkyGeo developed a stochastic model to predict differential subsidence and the probability of consequent pipeline failure on a (sub-)street level. In this project pipeline data from company databases is combined with a stochastic geological model and information on (historical) groundwater levels and overburden material. Probability of pipeline failure is modelled by a coupling with a subsidence model and two separate models on pipeline behaviour under stress, using a probabilistic approach. The total length of pipelines (approx. 200.000 km operational in the Netherlands) and the complexity of the model chain that is needed to calculate a chance of failure, results in large computational challenges, as it requires massive evaluation of possible scenarios to reach the required level of confidence. To cope with this, a scalable computational infrastructure has been developed, composing a model workflow in which components have a heterogeneous technological basis. Three pilot areas covering an urban, a rural and a mixed environment, characterised by different groundwater-management strategies and different overburden histories, are used to evaluate the differences in subsidence and uncertainties that come with

  17. ANME-2D Archaea Catalyze Methane Oxidation in Deep Subsurface Sediments Independent of Nitrate Reduction

    Science.gov (United States)

    Hernsdorf, A. W.; Amano, Y.; Suzuki, Y.; Ise, K.; Thomas, B. C.; Banfield, J. F.

    2015-12-01

    -reducing/oxidizing archaeon Ferroglobus placidus. Thus, we suggest that ANME2-D may couple methane oxidation to reduction of ferric iron minerals in the sediment and may be generally important as a link between the iron and methane cycles in deep subsurface environments. Such information has important implications for modeling the global carbon cycle.

  18. Modeling subsurface transport in extensive glaciofluvial and littoral sediments to remediate a municipal drinking water aquifer

    Directory of Open Access Journals (Sweden)

    M. Bergvall

    2011-07-01

    Full Text Available Few studies have been carried out that cover the entire transport process of pesticides, from application at the soil surface, through subsurface transport, to contamination of drinking water in esker aquifers. In formerly glaciated regions, such as Scandinavia, many of the most important groundwater resources are situated in glaciofluvial eskers. The purpose of the present study was to model and identify significant processes that govern subsurface transport of pesticides in extensive glaciofluvial and littoral sediments. To simulate the transport processes, we coupled a vadose zone model at soil profile scale to a regional groundwater flow model. The model was applied to a municipal drinking-water aquifer, contaminated with the pesticide-metabolite BAM (2,6-dichlorobenzoamide. At regional scale, with the combination of a ten-meter-deep vadose zone and coarse texture, the observed concentrations could be described by the model without assuming preferential flow. A sensitivity analysis revealed that hydraulic conductivity in the aquifer and infiltration rate accounted for almost half of the model uncertainty. The calibrated model was applied to optimize the location of extraction wells for remediation, which were used to validate the predictive modeling. Running a worst-case scenario, the model showed that the establishment of two remediation wells would clean the aquifer in four years, compared to nine years without them. Further development of the model would require additional field measurements in order to improve the description of macrodispersion in deep, sandy vadose zones. We also suggest that future research should focus on characterization of the variability of hydraulic conductivity and its effect on contaminant transport in eskers.

  19. Parameterizing deep water percolation improves subsurface temperature simulations by a multilayer firn model

    Science.gov (United States)

    Marchenko, Sergey; van Pelt, Ward J. J.; Claremar, Björn; Pohjola, Veijo; Pettersson, Rickard; Machguth, Horst; Reijmer, Carleen

    2017-03-01

    Deep preferential percolation of melt water in snow and firn brings water lower along the vertical profile than a laterally homogeneous wetting front. This widely recognized process is an important source of uncertainty in simulations of subsurface temperature, density and water content in seasonal snow and in firn packs on glaciers and ice sheets. However, observation and quantification of preferential flow is challenging and therefore it is not accounted for by most of the contemporary snow/firn models. Here we use temperature measurements in the accumulation zone of Lomonosovfonna, Svalbard, done in April 2012 - 2015 using multiple thermistor strings to describe the process of water percolation in snow and firn. Effects of water flow through the snow and firn profile are further explored using a coupled surface energy balance - firn model forced by the output of the regional climate model WRF. In situ air temperature, radiation and surface height change measurements are used to constrain the surface energy and mass fluxes. To account for the effects of preferential water flow in snow and firn we test a set of depth-dependent functions allocating a certain fraction of the melt water available at the surface to each snow/firn layer. Experiments are performed for a range of characteristic percolation depths and results indicate a reduction in root mean square difference between the modeled and measured temperature by up to a factor of two compared to the results from the default water infiltration scheme. This illustrates the significance of accounting for preferential water percolation to simulate subsurface conditions. The suggested approach to parameterization of the preferential water flow requires low additional computational cost and can be implemented in layered snow/firn models applied both at local and regional scales, for distributed domains with multiple mesh points.

  20. Ground-Coupled Heating-Cooling Systems in Urban Areas: How Sustainable Are They?

    Science.gov (United States)

    Younger, Paul L.

    2008-01-01

    Ground-coupled heating-cooling systems (GCHCSs) exchange heat between the built environment and the subsurface using pipework buried in trenches or boreholes. If heat pumps in GCHCSs are powered by "green electricity," they offer genuine carbon-free heating-cooling; for this reason, there has been a surge in the technology in recent…

  1. Techniques for assessing the performance of in situ bioreduction and immobilization of metals and radionuclides in contaminated subsurface environments

    Energy Technology Data Exchange (ETDEWEB)

    Jardine, P.M.; Watson, D.B.; Blake, D.A.; Beard, L.P.; Brooks, S.C.; Carley, J.M.; Criddle, C.S.; Doll, W.E.; Fields, M.W.; Fendorf, S.E.; Geesey, G.G.; Ginder-Vogel, M.; Hubbard, S.S.; Istok, J.D.; Kelly, S.; Kemner, K.M.; Peacock, A.D.; Spalding, B.P.; White, D.C.; Wolf, A.; Wu, W.; Zhou, J.

    2004-11-14

    Department of Energy (DOE) facilities within the weapons complex face a daunting challenge of remediating huge below inventories of legacy radioactive and toxic metal waste. More often than not, the scope of the problem is massive, particularly in the high recharge, humid regions east of the Mississippi river, where the off-site migration of contaminants continues to plague soil water, groundwater, and surface water sources. As of 2002, contaminated sites are closing rapidly and many remediation strategies have chosen to leave contaminants in-place. In situ barriers, surface caps, and bioremediation are often the remedial strategies of chose. By choosing to leave contaminants in-place, we must accept the fact that the contaminants will continue to interact with subsurface and surface media. Contaminant interactions with the geosphere are complex and investigating long term changes and interactive processes is imperative to verifying risks. We must be able to understand the consequences of our action or inaction. The focus of this manuscript is to describe recent technical developments for assessing the performance of in situ bioremediation and immobilization of subsurface metals and radionuclides. Research within DOE's NABIR and EMSP programs has been investigating the possibility of using subsurface microorganisms to convert redox sensitive toxic metals and radionuclides (e.g. Cr, U, Tc, Co) into a less soluble, less mobile forms. Much of the research is motivated by the likelihood that subsurface metal-reducing bacteria can be stimulated to effectively alter the redox state of metals and radionuclides so that they are immobilized in situ for long time periods. The approach is difficult, however, since subsurface media and waste constituents are complex with competing electron acceptors and hydrogeological conditions making biostimulation a challenge. Performance assessment of in situ biostimulation strategies is also difficult and typically requires detailed

  2. What is the current state of the science of Cyber defense?

    Energy Technology Data Exchange (ETDEWEB)

    Hurd, Alan J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-09

    My overall sense of the cyber defense field is one of an adolescent discipline currently bogged down in a cloud of issues, the most iconic of which is the great diversity of approaches that are being aggregated to form a coherent field. Because my own expertise is complex systems and materials physics research, I have limited direct experience in cyber security sciences except as a user of secure networks and computing resources. However, in producing this report, I have found with certainty that there exists no calculus for cyber risk assessment, mitigation, and response, although some hopeful precepts toward this end are emerging.

  3. Effects of acid deposition on ecosystems: Advances in the state of the science

    Science.gov (United States)

    Burns, Douglas A.; Fenn, Mark E.; Baron, Jill S.

    2011-01-01

    Chapter 2 focused on the environmental results of the ARP, presenting data from national monitoring networks on SO2 and NOx emissions, air quality, atmospheric deposition, surface water chemistry, and visibility. This chapter expands on this information by examining the most recent research into how ecosystems respond to acid deposition, especially the processes that control the recovery of ecosystems as acid deposition decreases. In Chapter 2, two general trends were discussed regarding the current recovery status of affected ecosystems: (1) these ecosystems are trending generally towards recovery, but improvements in ecosystem condition shown by surface water chemistry monitoring data thus far have been less than the improvements in deposition; and (2) ecosystem impacts and trends vary widely by geographic region, but the evidence of improvement is strongest and most evident in the Northeast. These trends are not uniform across the United States, however, and in some regions (e.g., central Appalachian Mountain region), trends in improved water quality are generally not evident. Despite the strong link in many areas between reduced emissions and reduced acidity of atmospheric deposition, the link is less clear between reduced acidity and recovery of the biological communities that live in aquatic and terrestrial ecosystems that have experienced deleterious effects from acid deposition. The recovery of these communities is proceeding at a slower pace than, for example, the improvements in stream and lake ANC would indicate. The goal of this chapter is to synthesize the science in a weightof-evidence manner to provide policy makers with tangible evidence and likely causative factors regarding ecosystem status and recovery patterns to date. This chapter serves as an update to the 2005 NAPAP RTC (NSTC, 2005), with an emphasis on scientific studies and monitoring since 2003, which was the last year for consideration of research results in the 2005 report. Several issues pertinent to ecosystem response to emission controls and acid deposition are receiving increasing attention in the scientific literature and will be discussed in this chapter, including the (1) observed delay in ecosystem recovery in the eastern United States, even with decreases in emissions and deposition over the past 30 years; (2) emerging ecosystem impacts of nitrogen deposition in the western United States; (3) the application of critical deposition loads as a tool for scientists to better inform air quality policies; (4) the role of changes in climate and the carbon cycle as factors that affect the response of ecosystems to acid deposition; and (5) the interaction of multiple pollutants in ecosystems. Throughout this chapter, the value of long-term environmental monitoring data in informing air quality policy will be highlighted, including the limitations of assessing the current status of some ecosystem indicators for which continuous, long-term data are lacking. 

  4. Single Subject Controlled Experiments in Aphasia: The Science and the State of the Science

    Science.gov (United States)

    Thompson, Cynthia K.

    2006-01-01

    This paper discusses the use of single subject controlled experimental designs for investigating the effects of treatment for aphasia. A brief historical perspective is presented, followed by discussions of the advantages and disadvantages of single subject and group approaches, the basic requirements of single subject experimental research, and…

  5. Occupational exposures in the oil and gas extraction industry: State of the science and research recommendations.

    Science.gov (United States)

    Witter, Roxana Z; Tenney, Liliana; Clark, Suzanne; Newman, Lee S

    2014-07-01

    The oil and gas extraction industry is rapidly growing due to horizontal drilling and high volume hydraulic fracturing (HVHF). This growth has provided new jobs and economic stimulus. The industry occupational fatality rate is 2.5 times higher than the construction industry and 7 times higher than general industry; however injury rates are lower than the construction industry, suggesting injuries are not being reported. Some workers are exposed to crystalline silica at hazardous levels, above occupational health standards. Other hazards (particulate, benzene, noise, radiation) exist. In this article, we review occupational fatality and injury rate data; discuss research looking at root causes of fatal injuries and hazardous exposures; review interventions aimed at improving occupational health and safety; and discuss information gaps and areas of needed research. We also describe Wyoming efforts to improve occupational safety in this industry, as a case example. © 2014 Wiley Periodicals, Inc.

  6. Measuring the built environment for physical activity: state of the science.

    Science.gov (United States)

    Brownson, Ross C; Hoehner, Christine M; Day, Kristen; Forsyth, Ann; Sallis, James F

    2009-04-01

    Physical inactivity is one of the most important public health issues in the U.S. and internationally. Increasingly, links are being identified between various elements of the physical-or built-environment and physical activity. To understand the impact of the built environment on physical activity, the development of high-quality measures is essential. Three categories of built environment data are being used: (1) perceived measures obtained by telephone interview or self-administered questionnaires; (2) observational measures obtained using systematic observational methods (audits); and (3) archival data sets that are often layered and analyzed with GIS. This review provides a critical assessment of these three types of built-environment measures relevant to the study of physical activity. Among perceived measures, 19 questionnaires were reviewed, ranging in length from 7 to 68 questions. Twenty audit tools were reviewed that cover community environments (i.e., neighborhoods, cities), parks, and trails. For GIS-derived measures, more than 50 studies were reviewed. A large degree of variability was found in the operationalization of common GIS measures, which include population density, land-use mix, access to recreational facilities, and street pattern. This first comprehensive examination of built-environment measures demonstrates considerable progress over the past decade, showing diverse environmental variables available that use multiple modes of assessment. Most can be considered first-generation measures, so further development is needed. In particular, further research is needed to improve the technical quality of measures, understand the relevance to various population groups, and understand the utility of measures for science and public health.

  7. State of the science: VLED (Very Low Energy Diet) for obesity.

    Science.gov (United States)

    Delbridge, Elizabeth; Proietto, Joseph

    2006-01-01

    It is often stated, "the faster you lose weight, the faster it is regained ". A review of existing literature does not support such a statement--indeed if anything the reverse is true. The origins of this erroneous view are the misconceptions that weight regain is a simple matter of bad dietary and social habits and that it takes time to change these, that physiological adaptations to rapid weight loss are different to those of gradual weight loss and that weight regain is simply due to a return to old habits. Indeed there are many advantages to rapid weight loss achieved with the use of a modern very low energy diet, including the fact that rapid weight loss is a motivating factor, that the mild ketosis that occurs not only suppresses hunger, but also slows protein loss and that adherence is easier with a structured dietary regime. VLEDs are dietary preparations that provide all nutritional requirements together with between 1845 and 3280 KJ (450 and 800 Kcal) per day. An individual takes this meal replacement three times daily as a substitute for breakfast, lunch and dinner. In addition, a bowl of non-starchy vegetables once daily provides some fibre and helps to satisfy the social aspect of eating. A teaspoon of oil on the vegetables contracts the gall bladder to minimise the risk of gall stone formation. Since weight loss, at whatever rate, results in physiological adaptations leading to weight regain, careful attention must be paid to the period after the VLED regime is completed. Lifestyle modification, diet and exercise are instituted optimally with behaviour modification. If, despite the subject's best efforts, weight regain occurs, an appetite suppressant is advisable to help control the drive to eat.

  8. Arsenic and Environmental Health: State of the Science and Future Research Opportunities

    Science.gov (United States)

    Background: Exposure to inorganic and organic arsenic compounds is a major public health problem that affects hundreds of millions of people worldwide. Exposure to arsenic is associated with cancer and noncancer effects in nearly every organ in the body, and evidence is mounting ...

  9. State of the Science Meeting: Burn Care: Goals for Treatment and Research

    Science.gov (United States)

    2006-11-01

    artery or valvular disease , which can manifest as myocardial dysfunction or infarction during the stress of injury. (19) The use of invasive...ranging from acute burn care through the rehabilitative period were addressed in a single forum and published in the Journal of Burn Care and...speaker list is included in the Appendix. Briefly, the topics covered included: acute care (inhalation injury, resuscitation, infection/inflammation

  10. Single subject controlled experiments in aphasia: The science and the state of the science

    OpenAIRE

    Thompson, Cynthia K.

    2006-01-01

    This paper discusses the use of single subject controlled experimental designs for investigating the effect of treatment for aphasia. A brief historical perspective is presented, followed by discussions of the advantages and disadvantages of single subject and group approaches, the basic requirements of single subject experimental research, and crucial considerations in design selection. In the final sections, results of reviews of published single subject controlled experiments are discussed...

  11. Youth Marijuana Use: State of the Science for the Practicing Clinician

    Science.gov (United States)

    Hadland, Scott E.; Harris, Sion K.

    2014-01-01

    Purpose of review Despite widespread marijuana use among adolescents, accurate information on known health effects is poorly disseminated to clinicians and their patients. Amidst rapidly evolving drug policy in the United States and elsewhere, it is imperative that providers understand the short- and long-term consequences of marijuana use. Recent findings Research on regular marijuana use highlights a unique susceptibility of the developing adolescent brain to adverse neurocognitive and psychiatric outcomes. Although studies have not firmly established causality, onset of regular marijuana use in adolescence is associated with later decline in cognitive function, as well as with adult onset of psychosis and anxiety. Educational and employment outcomes may be poorer among regular marijuana-using adolescents. A number of other adverse respiratory, cardiovascular, endocrine and gastrointestinal associations with regular marijuana use have also been established. Good screening tools and promising brief intervention and behavioral treatment programs are available to clinicians, who are in a position to identify problematic marijuana use among adolescents and refer for services. Summary A common misperception among youth is that marijuana use is without harm. However, adolescent marijuana use may have measurable, durable and potentially irreversible effects on later cognitive function and mental health. PMID:24914878

  12. Current state of the science: health effects and indoor environmental quality

    DEFF Research Database (Denmark)

    Mitchell, Clifford S; Zhang, Junfeng Jim; Sigsgaard, Torben

    2007-01-01

    Our understanding of the relationship between human health and the indoor environment continues to evolve. Previous research on health and indoor environments has tended to concentrate on discrete pollutant sources and exposures and on specific disease processes. Recently, efforts have been made...... environments. Advances in source characterization include a better understanding of how chemicals are transported and processed within spaces and the role that other factors such as lighting and building design may play in determining health. Efforts are under way to improve our ability to measure exposures...

  13. Cell transformation assays for prediction of carcinogenic potential: state of the science and future research needs.

    Science.gov (United States)

    Creton, Stuart; Aardema, Marilyn J; Carmichael, Paul L; Harvey, James S; Martin, Francis L; Newbold, Robert F; O'Donovan, Michael R; Pant, Kamala; Poth, Albrecht; Sakai, Ayako; Sasaki, Kiyoshi; Scott, Andrew D; Schechtman, Leonard M; Shen, Rhine R; Tanaka, Noriho; Yasaei, Hemad

    2012-01-01

    Cell transformation assays (CTAs) have long been proposed as in vitro methods for the identification of potential chemical carcinogens. Despite showing good correlation with rodent bioassay data, concerns over the subjective nature of using morphological criteria for identifying transformed cells and a lack of understanding of the mechanistic basis of the assays has limited their acceptance for regulatory purposes. However, recent drivers to find alternative carcinogenicity assessment methodologies, such as the Seventh Amendment to the EU Cosmetics Directive, have fuelled renewed interest in CTAs. Research is currently ongoing to improve the objectivity of the assays, reveal the underlying molecular changes leading to transformation and explore the use of novel cell types. The UK NC3Rs held an international workshop in November 2010 to review the current state of the art in this field and provide directions for future research. This paper outlines the key points highlighted at this meeting.

  14. Big Data and Clinicians: A Review on the State of the Science

    Science.gov (United States)

    Wang, Weiqi

    2014-01-01

    Background In the past few decades, medically related data collection saw a huge increase, referred to as big data. These huge datasets bring challenges in storage, processing, and analysis. In clinical medicine, big data is expected to play an important role in identifying causality of patient symptoms, in predicting hazards of disease incidence or reoccurrence, and in improving primary-care quality. Objective The objective of this review was to provide an overview of the features of clinical big data, describe a few commonly employed computational algorithms, statistical methods, and software toolkits for data manipulation and analysis, and discuss the challenges and limitations in this realm. Methods We conducted a literature review to identify studies on big data in medicine, especially clinical medicine. We used different combinations of keywords to search PubMed, Science Direct, Web of Knowledge, and Google Scholar for literature of interest from the past 10 years. Results This paper reviewed studies that analyzed clinical big data and discussed issues related to storage and analysis of this type of data. Conclusions Big data is becoming a common feature of biological and clinical studies. Researchers who use clinical big data face multiple challenges, and the data itself has limitations. It is imperative that methodologies for data analysis keep pace with our ability to collect and store data. PMID:25600256

  15. Alternative Testing Strategies for Nanomaterials: State of the Science and Considerations for Risk Analysis.

    Science.gov (United States)

    Shatkin, J A; Ong, K J

    2016-08-01

    The rapid growth of the nanotechnology industry has warranted equal progress in the nanotoxicology and risk assessment fields. In vivo models have traditionally been used to determine human and environmental risk for chemicals; however, the use of these tests has limitations, and there are global appeals to develop reliable alternatives to animal testing. Many have investigated the use of alternative (nonanimal) testing methods and strategies have quickly developed and resulted in the generation of large toxicological data sets for numerous nanomaterials (NMs). Due to the novel physicochemical properties of NMs that are related to surface characteristics, the approach toward toxicity test development has distinct considerations from traditional chemicals, bringing new requirements for adapting these approaches for NMs. The methodical development of strategies that combine multiple alternative tests can be useful for predictive NM risk assessment and help screening-level decision making. This article provides an overview of the main developments in alternative methods and strategies for reducing uncertainty in NM risk assessment, including advantages and disadvantages of in vitro, ex vivo, and in silico methods, and examples of existing comprehensive strategies. In addition, knowledge gaps are identified toward improvements for experimental and strategy design, specifically highlighting the need to represent realistic exposure scenarios and to consider NM-specific concerns such as characterization, assay interferences, and standardization. Overall, this article aims to improve the reliability and utility of alternative testing methods and strategies for risk assessment of manufactured NMs. © 2016 Society for Risk Analysis.

  16. Assessment and valuation of forest ecosystem services: State of the science review

    Science.gov (United States)

    Seth Binder; Robert G. Haight; Stephen Polasky; Travis Warziniack; Miranda H. Mockrin; Robert L. Deal; Greg. Arthaud

    2017-01-01

    This review focuses on the assessment and economic valuation of ecosystem services from forest ecosystems—that is, our ability to predict changes in the quantity and value of ecosystem services as a result of specific forest management decisions. It is aimed at forest economists and managers and intended to provide a useful reference to those interested in developing...

  17. Management of Contaminants Stored in Low Permeability Zones - A State of the Science Review

    Science.gov (United States)

    2013-10-01

    Treatment Timescales Associated with Source Depletion Technologies”, Volume 21, Issue 2, Spring 2011, Pages: 27–50 Adamson, DT and C.J. Newell, 2013...cm 17.5 cm source water = 0.21 mVC o silt silt silt sand sand sand APPENDIX C M A N A G E M E N T O F C O N T A M I N A N T S S T O R E D

  18. State of the science: does the theory of maternal role attainment apply to African American motherhood?

    Science.gov (United States)

    Fouquier, Katherine Ferrell

    2013-01-01

    This article reviews the current state of knowledge of the theory of maternal role attainment (MRA) and its relevance in describing African American motherhood. EBSCOhost Research Databases that included PubMed, CINAHL plus, MEDLINE, PsycINFO, SCOPUS, and Web of Science were searched for journal articles that examined maternal identity and MRA. Keyword searches included maternal identity, maternal role attainment, becoming a mother, prenatal attachment, maternal-fetal attachment, and maternal-infant attachment. Inclusion criteria for this review were published journal articles of studies conducted in the United States, with a clear delineation of the theoretical framework of MRA. Journal articles that measured MRA among women with depression or medically fragile infants were excluded. Two hundred and twelve studies were reviewed; 25 studies, published between 1975 and 2007, met the inclusion criteria. Nine articles described the theory of MRA, 11 articles measured variables thought to influence MRA, and 6 articles described maternal-fetal attachment, a construct of MRA. Studies were reviewed, categorized, and analyzed to determine current knowledge of how the theory of MRA describes African American motherhood. Categories included studies describing the theoretical framework of maternal identity and MRA, studies measuring key variables thought to impact MRA, and studies measuring maternal-fetal attachment and maternal-infant attachment. The studies were limited by homogenous samples of upper-middle-class white women and low-income, single, African American adolescents. Study results of MRA cannot be generalized to African American women. Further research is essential to identify attributes influencing MRA, specifically among larger samples of African American women with demographics similar to that of the white populations that have been included in studies thus far. © 2013 by the American College of Nurse-Midwives.

  19. Antioxidants in foods: state of the science important to the food industry.

    Science.gov (United States)

    Finley, John W; Kong, Ah-Ng; Hintze, Korry J; Jeffery, Elizabeth H; Ji, Li Li; Lei, Xin Gen

    2011-07-13

    Antioxidant foods and ingredients are an important component of the food industry. In the past, antioxidants were used primarily to control oxidation and retard spoilage, but today many are used because of putative health benefits. However, the traditional message that oxidative stress, which involves the production of reactive oxygen species (ROS), is the basis for chronic diseases and aging is being reexamined. Accumulating evidence suggests that ROS exert essential metabolic functions and that removal of too many ROS can upset cell signaling pathways and actually increase the risk of chronic disease. It is imperative that the food industry be aware of progress in this field to present the science relative to foods in a forthright and clear manner. This may mean reexamining the health implications of adding large amounts of antioxidants to foods.

  20. VIRTUAL SYMPOSIUM: STATE OF THE SCIENCE--PPCPS AS ENVIRONMENTAL POLLUTANTS

    Science.gov (United States)

    This document provides a brief summary of how this pioneering meeting for the ACS was conducted, as well as some perspective and insights that could prove useful for those who might beinterested in organizing and hosting their own "virtual" meeting.

  1. Big data and clinicians: a review on the state of the science.

    Science.gov (United States)

    Wang, Weiqi; Krishnan, Eswar

    2014-01-17

    In the past few decades, medically related data collection saw a huge increase, referred to as big data. These huge datasets bring challenges in storage, processing, and analysis. In clinical medicine, big data is expected to play an important role in identifying causality of patient symptoms, in predicting hazards of disease incidence or reoccurrence, and in improving primary-care quality. The objective of this review was to provide an overview of the features of clinical big data, describe a few commonly employed computational algorithms, statistical methods, and software toolkits for data manipulation and analysis, and discuss the challenges and limitations in this realm. We conducted a literature review to identify studies on big data in medicine, especially clinical medicine. We used different combinations of keywords to search PubMed, Science Direct, Web of Knowledge, and Google Scholar for literature of interest from the past 10 years. This paper reviewed studies that analyzed clinical big data and discussed issues related to storage and analysis of this type of data. Big data is becoming a common feature of biological and clinical studies. Researchers who use clinical big data face multiple challenges, and the data itself has limitations. It is imperative that methodologies for data analysis keep pace with our ability to collect and store data.

  2. Digital Cognitive Behavioral Therapy (dCBT) for Insomnia: a State-of-the-Science Review.

    Science.gov (United States)

    Luik, Annemarie I; Kyle, Simon D; Espie, Colin A

    2017-01-01

    Over the past decade, digital solutions have been developed to support the dissemination of Cognitive Behavioral Therapy (CBT). In this paper, we review the evidence for and implications of digital CBT (dCBT) for insomnia. We propose three categories of dCBT, which differ in the amount of clinician time needed, level of automatization, costs, and scalability: dCBT as support, guided dCBT, and fully automated dCBT. Consistent evidence has been published on the effectiveness of dCBT to address insomnia disorder, in a variety of populations, with effects extending into well-being. Important gaps in the literature are identified around moderators and mediators of dCBT, cost-effectiveness, and the implementation of dCBT. The evidence base for dCBT is rapidly developing and already suggests that dCBT for insomnia is effective. However, further science and digital innovation is required to realize the full potential of dCBT and address important clinical questions.

  3. Case conceptualization research in cognitive behavior therapy: A state of the science review.

    Science.gov (United States)

    Easden, Michael H; Kazantzis, Nikolaos

    2017-08-04

    Prominent models of cognitive behavior therapy (CBT) assert that case conceptualization is crucial for tailoring interventions to adequately address the needs of the individual client. We aimed to review the research on case conceptualization in CBT. We conducted a systematic search of PsychINFO, MEDLINE, Psychology and Behavioral Science Collection, and CINAHL databases to February 2016. A total of 24 studies that met inclusion criteria were identified. It was notable that studies (a) focused on the assessment function of case conceptualization, (b) employed diverse methodologies, and, overall, (c) there remains a paucity of studies examining the in-session process of using case conceptualization or examining relations with outcome. Results from the existing studies suggest that experienced therapists can reliably construct some elements of case conceptualizations, but importance for the efficacy of case conceptualization in CBT has yet to be demonstrated. Research that involves direct observation of therapist competence in case conceptualization as a predictor of CBT outcomes is recommended as a focus for future hypothesis testing. © 2017 Wiley Periodicals, Inc.

  4. Cognitive changes associated with cancer and cancer treatment: state of the science.

    Science.gov (United States)

    Von Ah, Diane

    2015-02-01

    Cognitive impairment is a distressing, disruptive, and potentially debilitating symptom that can occur as a direct result of cancer or its treatment. National organizations have identified cognitive impairment as a challenge many survivors face and call for research to address this problem. Despite the priority, research is still relatively limited and questions remain unanswered about prevalence and impact on survivors, as well as coping strategies and effective treatment options available to address this potentially debilitating problem. The purpose of this article is to (a) analyze the prevalence and types of cognitive impairment that commonly affect survivors; (b) delineate the impact that cognitive impairment after cancer and cancer treatment has on self-esteem, social relationships, work ability, and overall quality of life among survivors; and (c) synthesize and appraise commonly used coping strategies used by survivors to address cognitive impairment and evidence-based interventions that may be incorporated into clinical practice. A comprehensive review and synthesis of the literature was conducted. Evidence-based interventions to address cognitive changes after cancer and cancer treatment are limited. However, emerging research has demonstrated that nonpharmacologic treatments, such as cognitive training, are likely to be effective.

  5. The routinization of innovation research : A constructively critical review of the state-of-the-science

    NARCIS (Netherlands)

    Anderson, N; De Dreu, CKW; Nijstad, BA

    In this review we argue that facilitators of innovation at the individual, group, and organizational levels have been reliably identified, and that validated process models of innovation have been developed. However, a content analysis of selected research published between 1997 and 2002 suggests a

  6. State of the science of health literacy measures: Validity implications for minority populations

    Science.gov (United States)

    Nguyen, Tam H.; Park, Hyunjeong; Han, Hae-Ra; Chan, Kitty S.; Paasche-Orlow, Michael K.; Haun, Jolie; Kim, Miyong T.

    2015-01-01

    Objectives To review the evidence supporting the validity of health literacy (HL) measures for ethnic minority populations. Methods PubMed, CINAHL, and PsycINFO databases were searched for HL measures between 1965 and 2013. Results A total of 109HL measures were identified; 37 were non-English HL measures and 72 were English language measures. Of the 72 English language measures, 17 did not specify the racial/ethnic characteristic of their sample. Of the remaining 55 measures, 10 (18%) did not include blacks, 30 (55%) did not include Hispanics, and 35 (64%) did not include Asians in their validation sample. When Hispanic and Asian Americans were included, they accounted for small percentages in the overall sample. Between 2005–2013, a growing number of REALM and TOFHLA translations were identified, and new HL measures for specific cultural/linguistic groups within and outside the United States were developed. Conclusions While there are a growing number of new and translated HL measures for minority populations, many existing HL measures have not been properly validated for minority groups. Practice Implications HL measures that have not been properly validated for a given population should be piloted before wider use. In addition, improving HL instrument development/validation methods are imperative to increase the validity of these measures for minority populations. PMID:26275841

  7. State Of The Science On Cogeneration Of Heat And Power From Anaerobic Digestion Of Municipal Biosolids

    Science.gov (United States)

    This presentation will report on work underway to inventory facilities currently utilizing biogas from anaerobic digestion and speak with practitioners to learn: techniques for preparing residuals for digestion, methods to use for cleaning biogas (e.g., of siloxane), and how gas...

  8. A Caries Vaccine? The state of the science of immunization against dental caries.

    Science.gov (United States)

    Russell, Michael W; Childers, Noel K; Michalek, Suzanne M; Smith, Daniel J; Taubman, Martin A

    2004-01-01

    Studies performed in numerous laboratories over several decades have demonstrated the feasibility of immunizing experimental rodents or primates with protein antigens derived from Streptococcus mutans or Streptococcus sobrinus against oral colonization by mutans streptococci and the development of dental caries. Protection has been attributed to salivary IgA antibodies which can inhibit sucrose-independent or sucrose-dependent mechanisms of streptococcal accumulation on tooth surfaces according to the choice of vaccine antigen. Strategies of mucosal immunization have been developed to induce high levels of salivary antibodies that can persist for prolonged periods and to establish immune memory. Studies in humans show that salivary antibodies to mutans streptococci can be induced by similar approaches, and that passively applied antibodies can also suppress oral re-colonization by mutans streptococci. Progress towards practical vaccine development requires evaluation of candidate vaccines in clinical trials. Promising strategies of passive immunization also require further clinical evaluation. Copyright 2004 S. Karger AG, Basel

  9. Elements of change 1994. Climate-radiation feedbacks: The current state of the science

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This report presents the details of the Climate-Radiation Feedback summer seminar. Topics include: radiative transfer; radiative properties of clouds; absorption of radiation in the atmosphere due to clouds; global cloud climatology; aerosols; general circulation models; and convection. Individual papers have been indexed separately for the database.

  10. Cell transformation assays for prediction of carcinogenic potential: state of the science and future research needs

    Science.gov (United States)

    Creton, Stuart; Aardema, Marilyn J.; Carmichael, Paul L.; Harvey, James S.; Martin, Francis L.; Newbold, Robert F.; O’Donovan, Michael R.; Pant, Kamala; Poth, Albrecht; Sakai, Ayako; Sasaki, Kiyoshi; Scott, Andrew D.; Schechtman, Leonard M.; Shen, Rhine R.; Tanaka, Noriho; Yasaei, Hemad

    2012-01-01

    Cell transformation assays (CTAs) have long been proposed as in vitro methods for the identification of potential chemical carcinogens. Despite showing good correlation with rodent bioassay data, concerns over the subjective nature of using morphological criteria for identifying transformed cells and a lack of understanding of the mechanistic basis of the assays has limited their acceptance for regulatory purposes. However, recent drivers to find alternative carcinogenicity assessment methodologies, such as the Seventh Amendment to the EU Cosmetics Directive, have fuelled renewed interest in CTAs. Research is currently ongoing to improve the objectivity of the assays, reveal the underlying molecular changes leading to transformation and explore the use of novel cell types. The UK NC3Rs held an international workshop in November 2010 to review the current state of the art in this field and provide directions for future research. This paper outlines the key points highlighted at this meeting. PMID:21852270

  11. Passive sampling methods for contaminated sediments: State of the science for metals

    Science.gov (United States)

    Peijnenburg, Willie JGM; Teasdale, Peter R; Reible, Danny; Mondon, Julie; Bennett, William W; Campbell, Peter GC

    2014-01-01

    “Dissolved” concentrations of contaminants in sediment porewater (Cfree) provide a more relevant exposure metric for risk assessment than do total concentrations. Passive sampling methods (PSMs) for estimating Cfree offer the potential for cost-efficient and accurate in situ characterization of Cfree for inorganic sediment contaminants. In contrast to the PSMs validated and applied for organic contaminants, the various passive sampling devices developed for metals, metalloids, and some nonmetals (collectively termed “metals”) have been exploited to a limited extent, despite recognized advantages that include low detection limits, detection of time-averaged trends, high spatial resolution, information about dissolved metal speciation, and the ability to capture episodic events and cyclic changes that may be missed by occasional grab sampling. We summarize the PSM approaches for assessing metal toxicity to, and bioaccumulation by, sediment-dwelling biota, including the recognized advantages and limitations of each approach, the need for standardization, and further work needed to facilitate broader acceptance and application of PSM-derived information by decision makers. Integr Environ Assess Manag 2014;10:179–196. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC. Key Points Passive sampling methods (PSMs) offer the potential for cost-efficient and accurate in situ characterization of the dissolved concentrations for inorganic sediment contaminants. PSMs are useful for evaluating the geochemical behavior of metals in surficial sediments, including determination of fluxes across the sediment-water interface, and post-depositional changes in metal speciation. Few studies have tried to link PSM responses in sediments to metal uptake and toxicity responses in benthic organisms. There is a clear need for further studies. Future PSMs could be designed to mimic saturable kinetics, which would fill the gap between the kinetic and the equilibrium regime samplers currently used, and may improve prediction of metals accumulation by benthic organisms. PMID:24470168

  12. Passive sampling methods for contaminated sediments: State of the science for organic contaminants

    Science.gov (United States)

    Lydy, Michael J; Landrum, Peter F; Oen, Amy MP; Allinson, Mayumi; Smedes, Foppe; Harwood, Amanda D; Li, Huizhen; Maruya, Keith A; Liu, Jingfu

    2014-01-01

    This manuscript surveys the literature on passive sampler methods (PSMs) used in contaminated sediments to assess the chemical activity of organic contaminants. The chemical activity in turn dictates the reactivity and bioavailability of contaminants in sediment. Approaches to measure specific binding of compounds to sediment components, for example, amorphous carbon or specific types of reduced carbon, and the associated partition coefficients are difficult to determine, particularly for native sediment. Thus, the development of PSMs that represent the chemical activity of complex compound–sediment interactions, expressed as the freely dissolved contaminant concentration in porewater (Cfree), offer a better proxy for endpoints of concern, such as reactivity, bioaccumulation, and toxicity. Passive sampling methods have estimated Cfree using both kinetic and equilibrium operating modes and used various polymers as the sorbing phase, for example, polydimethylsiloxane, polyethylene, and polyoxymethylene in various configurations, such as sheets, coated fibers, or vials containing thin films. These PSMs have been applied in laboratory exposures and field deployments covering a variety of spatial and temporal scales. A wide range of calibration conditions exist in the literature to estimate Cfree, but consensus values have not been established. The most critical criteria are the partition coefficient between water and the polymer phase and the equilibrium status of the sampler. In addition, the PSM must not appreciably deplete Cfree in the porewater. Some of the future challenges include establishing a standard approach for PSM measurements, correcting for nonequilibrium conditions, establishing guidance for selection and implementation of PSMs, and translating and applying data collected by PSMs. Integr Environ Assess Manag 2014;10:167–178. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC. PMID:24307344

  13. Experimental pain processing in individuals with cognitive impairment: current state of the science

    DEFF Research Database (Denmark)

    Defrin, R; Amanzio, Martina; de Tomasso, M

    2015-01-01

    clinical condition) and may also depend on the type of pain stimulation used and the type of pain responses assessed. Nevertheless, it is clear that regardless of the etiology of CI, patients do feel noxious stimuli; with more evidence for hypersensitivity than hyposensitivity to these stimuli compared...

  14. Modular evaluation method for subsurface activities (MEMSA). A novel approach for integrating social acceptance in a permit decision-making process for subsurface activities

    NARCIS (Netherlands)

    van Os, Herman; Herber, Rien; Scholtens, Bert

    We investigate how the decision support system 'Modular Evaluation Method Subsurface Activities' (MEMSA) can help facilitate an informed decision-making process for permit applications of subsurface activities. To this end, we analyze the extent the MEMSA approach allows for a dialogue between

  15. Evaluation of spatially resolved diffuse reflectance imaging for subsurface pattern visualization towards applicability for fiber optic lensless imaging setup: phantom experiments and simulation

    Science.gov (United States)

    Schelkanova, I.; Pandya, A.; Saiko, G.; Nacy, L.; Babar, H.; Shah, D.; Lilge, L.; Douplik, A.

    2015-07-01

    A portable, spatially resolved diffuse reflectance (SRDR) lensless imaging technique based on the charge coupled device (CCD), or complementary metal-oxide semiconductor (CMOS) sensor directly coupled with fiber optic bundle can be proposed for visualization of subsurface structures such as intrapapillary capillary loops (IPCLs). In this article, we discuss an experimental method for emulating a lensless imaging setup via raster scanning a single fiberoptic cable (where image is relayed onto the sensor surface through a fiber-optic cable equivalent to coupling a fiber optic conduit directly onto the sensor surface without any lenses) over a microfluidic phantom containing periodic hemoglobin absorption contrast. For mimicking scattering properties of turbid media, a diffusive layer formed of polydimethylsiloxane (PDMS) and titanium dioxide (TiO2) was placed atop of the microfluidic phantom. Thickness of the layers ranged from 0.2-0.7mm, and the μs` value of the layers were in the range of 0.85 mm-1 - 4.25mm-1. The results demonstrate that a fiber-optic bundle/plate coupled lensless imaging setup has a high potential to recover intensity modulations from the subsurface patterns. Decreasing of the interrogation volumes leads to enhanced spatial resolution of diffuse reflectance imaging, and hence, can potentially overcome the scattering caused blurring.

  16. Subsurface imaging across the 2001 Spokane, Washington earthquake swarm

    Science.gov (United States)

    Finn, S.; Stephenson, W. J.; Wicks, C. W.; Pratt, T. L.; Odum, J. K.; Angster, S. J.

    2012-12-01

    We acquired 4 km of minivibe reflection seismic data in Spokane, Washington, to image subsurface deformation associated with the 2001 swarm of shallow (collected by USGS as part of ongoing earthquake hazards investigations in the area. In 2001 unexplained earthquake ground shaking as well as audible "booms" were reported over a span of six months (June to November) in the Emerson-Garfield and West Central neighborhoods of Spokane.; the area has since been seismically quiescent. Seismograph recordings of the earthquake swarm suggest shallow depths of hypocenters, yet the local subsurface geology is not well known. Although the source region of this swarm is poorly constrained within Spokane due to sparse seismic station coverage in the area at that time, recent InSAR data analysis has revealed a zone of surface deformation that may be related to the earthquake swarm. This surface deformation consists of an elliptical area about 3 km across that had as much as 15 mm of uplift during 2001. Preliminary processing of the two new seismic profiles provides the first subsurface images of the upper 500 m within the Spokane area across the inferred source region. One seismic profile through downtown Spokane shows a three-layer structure of Holocene valley fill and Quaternary Lake Missoula flood deposits underlain by Tertiary Columbia River basalts. We observe a Columbia River basalt bedrock high of 100 m located between seismic profiles and verified by geologic and aeromagnetic maps. The seismic data also image a paleochannel showing the migration of the Spokane River through time. An inflection within the Quaternary basin sediment reflections suggests uplift from faulting that is consistent with the sense of deformation observed in the InSAR data.

  17. ASEST - a Convenient Software Package for Subsurface Problems

    Science.gov (United States)

    Shan, C.

    2004-12-01

    In February 2004, Shans' Groundwater published a two-volume book, Analytical Solutions in Excel for Subsurface Transport (abbreviated as ASEST). Authored by C. Shan, the book has a large collection of analytical solutions for flow of water (or gas) and transport of chemicals in the subsurface. Solutions for aquifer problems are in Volume I, and solutions for vadose zone in Volume II. For each of the selected problems, the book gives the corresponding assumptions, the governing equation, the boundary/initial conditions, and the analytical solution. All analytical solutions are programmed in Microsoft Excel ('97 version), which are loaded on a CD (totally 60 programs). The procedures, tips, and examples for running these programs are given in the book. To run a program, users simply open the Excel file and go to Sheet1, type input data in a table, and click a run button below the table. It usually takes a few seconds or minutes to run the program, which outputs the resulting data on Sheet2. For a two-column output, a figure is usually shown on Sheet3. ASEST is a convenient software package for solving many kinds of subsurface problems. It is also designed for everyone: university professors can use it in preparing their lectures, graduate students can use it in their course study and thesis preparation, researchers can use it to analyze data from laboratory or field experiments, code developers can use it to verify their numerical programs, and consultant engineers can use it to obtain some first-cut results for their projects. More detailed information about the book is given at the website: http://www.shans-groundwater.com .

  18. Microbial Colonization of Earth's Subsurface: A Thermodynamically Consistent Perspective

    Science.gov (United States)

    Bethke, C. M.; Sanford, R. A.; Jin, Q.; Kirk, M. F.

    2014-12-01

    The nature of how anaerobic microbes have come to distribute themselves within Earth's crust is an ecologic question that must be posed subject to the laws of thermodynamics, but a question that cannot be understood in light of thermodynamics alone. We use here the results of theory and quantitative modeling, field observations, and long-term laboratory experiments to argue that subsurface communities are composed of groups of microbes that cooperate as well as compete, and whose existence reflects a tight balance between reproduction and cell death. The most significant functional groups colonizing the anoxic crust, classified by electron accepting process, are the methanogens, sulfate reducers, and ferric iron reducers. An anaerobe can harvest the energy it needs to live and reproduce only to the extent that energy available to it in the environment exceeds the cell's internal levels. When methanogens transfer or dismutate electrons, they capture little energy, so as to preserve a thermodynamic drive for their catabolic reaction. In this way, they maximize their environmental range, but grow slowly. Sulfate reducers adopt a different strategy, striving to capture energy quickly and grow rapidly. Iron reduction consumes acid, so the energy available to iron reducers varies sharply with pH. The iron reducers can grow rapidly under acidic conditions, but an alkaline environment may leave them insufficient energy to live. Methane producers are vulnerable to exclusion in the subsurface, as is broadly appreciated, but not because of energetic limitations. Instead, the methanogens require abundant energy substrates in order to reproduce quickly enough to replace cells as they die. Sulfate reducers and iron reducers, instead of working to exclude each other by competing for limited energy sources, as is commonly believed, thrive in mutualistic communities. The three functional groups by necessity compete in their environments for limited sources of energy, but the manner

  19. Progression of methanogenic degradation of crude oil in the subsurface

    Science.gov (United States)

    Bekins, B.A.; Hostettler, F.D.; Herkelrath, W.N.; Delin, G.N.; Warren, E.; Essaid, H.I.

    2005-01-01

    Our results show that subsurface crude-oil degradation rates at a long-term research site were strongly influenced by small-scale variations in hydrologic conditions. The site is a shallow glacial outwash aquifer located near Bemidji in northern Minnesota that became contaminated when oil spilled from a broken pipeline in August 1979. In the study area, separate-phase oil forms a subsurface oil body extending from land surface to about 1 m (3.3 ft) below the 6-8-m (20-26 ft)-deep water table. Oil saturation in the sediments ranges from 10-20% in the vadose zone to 30-70% near the water table. At depths below 2 m (6.6 ft), degradation of the separate-phase crude oil occurs under methanogenic conditions. The sequence of methanogenic alkane degradation depletes the longer chain n-alkanes before the shorter chain n-alkanes, which is opposite to the better known aerobic sequence. The rates of degradation vary significantly with location in the subsurface. Oil-coated soils within 1.5 m (5 ft) of land surface have experienced little degradation where soil water saturation is less than 20%. Oil located 2-8 m (6.6-26 ft) below land surface in areas of higher recharge has been substantially degraded. The best explanation for the association between recharge and enhanced degradation seems to be increased downward transport of microbial growth nutrients to the oil body. This is supported by observations of greater microbial numbers at higher elevations in the oil body and significant decreases with depth in nutrient concentrations, especially phosphorus. Our results suggest that environmental effects may cause widely diverging degradation rates in the same spill, calling into question dating methods based on degradation state. Copyright ?? 2005. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

  20. Reactive Oxygen Species are Ubiquitous along Subsurface Redox Gradients

    Science.gov (United States)

    Nico, P. S.; Yuan, X.; Davis, J. A.; Dwivedi, D.; Williams, K. H.; Bhattacharyya, A.; Fox, P. M.

    2016-12-01

    Reactive oxygen species (hydroxyl radical, superoxide, hydrogen peroxide, etc.) are known to be important intermediates in many biological and earth system processes. They have been particularly well studied in the realms of atmospheric chemistry and aquatic photochemistry. However, recently there is increasing evidence that they are also present in impactful quantities in dark systems as a result of both biotic and abiotic reactions. Herein we will present a complementary suite of laboratory and field studies examining the presence and production of hydrogen peroxide under relevant subsurface conditions. The laboratory work examines the redox cycling between reduced organic matter, molecular oxygen, and Fe which results in not only the production of hydrogen peroxide and oxidation of organic functional groups but also the maintenance of steady-state concentration of Fe(II) under fully oxygenated aqueous conditions. The field studies involve three distinct locations, namely a shallow subsurface aquifer, a hyporheic zone redox gradient across a river meander, and a hillside shale seep. In all cases detectable quantities (tens of nanomolar) of hydrogen peroxide were measured. In general, concentrations peak under transitional redox conditions where there is the simultaneous presence of reduced Fe, organic matter, and at least trace dissolved oxygen. Many, but not all, of the observed dynamics in hydrogen peroxide production can be reproduced by a simple kinetic model representing the reactions between Fe, organic matter, and molecular oxygen, but many questions remain regarding the role of microorganisms and other redox active chemical species in determining the detected hydrogen peroxide concentrations. The consistent detection of hydrogen peroxide at these disparate locations supports the hypothesis that hydrogen peroxide, and by extension, the entire suite of reactive oxygen species are ubiquitous along subsurface redox gradients.

  1. SeiVis: An interactive visual subsurface modeling application

    KAUST Repository

    Hollt, Thomas

    2012-12-01

    The most important resources to fulfill today’s energy demands are fossil fuels, such as oil and natural gas. When exploiting hydrocarbon reservoirs, a detailed and credible model of the subsurface structures is crucial in order to minimize economic and ecological risks. Creating such a model is an inverse problem: reconstructing structures from measured reflection seismics. The major challenge here is twofold: First, the structures in highly ambiguous seismic data are interpreted in the time domain. Second, a velocity model has to be built from this interpretation to match the model to depth measurements from wells. If it is not possible to obtain a match at all positions, the interpretation has to be updated, going back to the first step. This results in a lengthy back and forth between the different steps, or in an unphysical velocity model in many cases. This paper presents a novel, integrated approach to interactively creating subsurface models from reflection seismics. It integrates the interpretation of the seismic data using an interactive horizon extraction technique based on piecewise global optimization with velocity modeling. Computing and visualizing the effects of changes to the interpretation and velocity model on the depth-converted model on the fly enables an integrated feedback loop that enables a completely new connection of the seismic data in time domain and well data in depth domain. Using a novel joint time/depth visualization, depicting side-by-side views of the original and the resulting depth-converted data, domain experts can directly fit their interpretation in time domain to spatial ground truth data. We have conducted a domain expert evaluation, which illustrates that the presented workflow enables the creation of exact subsurface models much more rapidly than previous approaches. © 2012 IEEE.

  2. Application, evaluation and sensitivity analysis of the coupled WRF-CMAQ system from regional to urban scales

    Science.gov (United States)

    The Community Multiscale Air Quality (CMAQ) model is a state-of-the-science chemical transport model (CTM) capable of simulating the emission, transport and fate of numerous air pollutants. Similarly, the Weather Research and Forecasting (WRF) model is a state-of-the-science mete...

  3. Growth of nanoparticles in hydrogen-implanted palladium subsurfaces

    Energy Technology Data Exchange (ETDEWEB)

    Okuyama, F. [Nagoya Institute of Technology, Graduate School of Engineering, Nagoya (Japan)

    2010-07-15

    Solid particles with nanometric dimensions are shown to grow in the opened subsurface of a polycrystalline palladium (Pd) hydrogen-implanted at around 500 C. The particles are Pd in main composition and densely grown on sloping walls of fissured grain boundaries or cracks. The average grain size increases from deeper to shallow regions, suggesting that a negative temperature gradient toward the surface existed along the crack walls. The nanoparticles are certain to arise from the condensation of Pd vapors on the walls, forcing us to assume that hydrogen atoms implanted in an overpopulation heated their implantation zone so strongly as to vaporize Pd. (orig.)

  4. Characterizing subsurface textural properties using electromagnetic induction mapping and geostatistics

    Science.gov (United States)

    Abdu, Hiruy

    Knowledge of the spatial distribution of soil textural properties at the watershed scale is important for understanding spatial patterns of water movement, and in determining soil moisture storage and soil hydraulic transport properties. Capturing the heterogeneous nature of the subsurface without exhaustive and costly sampling presents a significant challenge. Soil scientists and geologists have adapted geophysical methods that measure a surrogate property related to the vital underlying process. Apparent electrical conductivity (ECa) is such a proxy, providing a measure of charge mobility due to application of an electric field, and is highly correlated to the electrical conductivity of the soil solution, clay percentage, and water content. Electromagnetic induction (EMI) provides the possibility of obtaining high resolution images of ECa across a landscape to identify subtle changes in subsurface properties. The aim of this study was to better characterize subsurface textural properties using EMI mapping and geostatistical analysis techniques. The effect of variable temperature environments on EMI instrumental response, and EC a -- depth relationship were first determined. Then a procedure of repeated EMI mapping at varying soil water content was developed and integrated with temporal stability analysis to capture the time invariant properties of spatial soil texture on an agricultural field. In addition, an EMI imaging approach of densely sampling the subsurface of the Reynolds Mountain East watershed was presented using kriging to interpolate, and Sequential Gaussian Simulation to estimate the uncertainty in the maps. Due to the relative time-invariant characteristics of textural properties, it was possible to correlate clay samples collected over three seasons to ECa data of one mapping event. Kriging methods [ordinary kriging (OK), cokriging (CK), and regression kriging (RK)] were then used to integrate various levels of information (clay percentage, ECa

  5. Preliminary Investigation of Linkages Between Arctic Pingos and Subsurface Stratigraphy

    Science.gov (United States)

    Casavant, R.; Skirvin, S.; Patel, C.; Burr, D.

    2008-12-01

    This NASA-SETI supported study investigates the distribution of pingos (elliptically-shaped ice-rich topographic mounds) across 2300 square kilometers of the central coastal plain of Arctic Alaska in relation to the shallow geological framework that exists immediately beneath them. Pingos in the central North Slope of Alaska are classified as being of the closed or hydrostatic type. Their genesis is often assigned to freezing and cryogenic uplift of near-surface saturated thaw lake sediments that are exposed as lakes are drained and/or become choked with sediments. Although thaw lakes appear rather ubiquitous across the study area, pingos do not. Pingo distributions can be categorized as either clusters of elements or as relatively dispersed. Spatial statistical analysis reveals that pingo distribution is non-random and clustered. The analysis also took into account that pingo distribution is a function of preferential preservation between modern rivers channels that cross the study area. Pingo distributions and frequency were tested in relation to the location and type of stratigraphic and sedimentological features that characterized the shallow subsurface across the study area. Subsurface interpretation was derived mostly from oil well wireline logs. Gamma ray logs for more than 160 wells were used to define, correlate and assess the connectivity and conductivity of shallow and near-surface stratigraphic units between wells. Assessed also were major facies changes and the type and locations of subsurface structures such as major basement-to-surface faults and folds. The surface and near-surface truncation and subcropping of tilted, alternating units of permeable coarse-grained and confining fine- grained units were also mapped in relation to pingo locations. Preliminary and intriguing findings will be presented which contribute to the hypothesis that pingo genesis, location, and variations in morphology could be, in part, linked to a well-documented and active

  6. CLEAN Technique to Classify and Detect Objects in Subsurface Imaging

    Directory of Open Access Journals (Sweden)

    E. Karpat

    2012-01-01

    Full Text Available An image domain CLEAN technique, for nondestructive and noncontacting subsurface imaging, is discussed. Recently introduced finite-difference time-domain- (FDTD- based virtual tool, GrGPR, is used to create imaging scenarios and to generate synthetic scattering data through synthetic aperture (SAR type scanning. Matlab-based imaging algorithms are used to process recorded FDTD data. The location and the geometry of the targets are obtained by image domain CLEAN technique which is extracting scattering centers from the SAR image. The effectiveness of the algorithm is tested in simulated data.

  7. AMISS - Active and passive MIcrowaves for Security and Subsurface imaging

    Science.gov (United States)

    Soldovieri, Francesco; Slob, Evert; Turk, Ahmet Serdar; Crocco, Lorenzo; Catapano, Ilaria; Di Matteo, Francesca

    2013-04-01

    The FP7-IRSES project AMISS - Active and passive MIcrowaves for Security and Subsurface imaging is based on a well-combined network among research institutions of EU, Associate and Third Countries (National Research Council of Italy - Italy, Technische Universiteit Delft - The Netherlands, Yildiz Technical University - Turkey, Bauman Moscow State Technical University - Russia, Usikov Institute for Radio-physics and Electronics and State Research Centre of Superconductive Radioelectronics "Iceberg" - Ukraine and University of Sao Paulo - Brazil) with the aims of achieving scientific advances in the framework of microwave and millimeter imaging systems and techniques for security and safety social issues. In particular, the involved partners are leaders in the scientific areas of passive and active imaging and are sharing their complementary knowledge to address two main research lines. The first one regards the design, characterization and performance evaluation of new passive and active microwave devices, sensors and measurement set-ups able to mitigate clutter and increase information content. The second line faces the requirements to make State-of-the-Art processing tools compliant with the instrumentations developed in the first line, suitable to work in electromagnetically complex scenarios and able to exploit the unexplored possibilities offered by new instrumentations. The main goals of the project are: 1) Development/improvement and characterization of new sensors and systems for active and passive microwave imaging; 2) Set up, analysis and validation of state of art/novel data processing approach for GPR in critical infrastructure and subsurface imaging; 3) Integration of state of art and novel imaging hardware and characterization approaches to tackle realistic situations in security, safety and subsurface prospecting applications; 4) Development and feasibility study of bio-radar technology (system and data processing) for vital signs detection and

  8. Subsurface dimerization in III-V semiconductor (001) surfaces

    DEFF Research Database (Denmark)

    Kumpf, C.; Marks, L.D.; Ellis, D.

    2001-01-01

    We present the atomic structure of the c(8 X 2) reconstructions of InSb-, InAs-, and GaAs-(001) surfaces as determined by surface x-ray diffraction using direct methods. Contrary to common belief, group III dimers are not prominent on the surface, instead subsurface dimerization of group m atoms ...... takes place in the second bilayer, accompanied by a major rearrangement of the surface atoms above the dimers to form linear arrays. By varying the occupancies of four surface sites the (001)-c(8 X 2) reconstructions of III-V semiconductors can be described in a unified model....

  9. Surface and subsurface conditions in permafrost areas - a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Vidstrand, Patrik [Bergab, Goeteborg (Sweden)

    2003-02-01

    This report contains a summary of some of the information within existing technical and scientific literature on permafrost. Permafrost is viewed as one of the future climate driven process domains that may exist in Scandinavia, and that may give rise to significantly different surface and subsurface conditions than the present. Except for changes in the biosphere, permafrost may impact hydraulic, mechanical, and chemical subsurface processes and conditions. Permafrost and its influences on the subsurface conditions are thus of interest for the performance and safety assessments of deep geological waste repositories. The definition of permafrost is 'ground that stays at or below 0 deg C for at least two consecutive years'. Permafrost will effect the geological subsurface to some depth. How deep the permafrost may grow is a function of the heat balance, thermal conditions at the surface and within the ground, and the geothermal heat flux from the Earth's inner parts. The main chapters of the report summaries the knowledge on permafrost evolution, occurrence and distribution, and extracts information concerning hydrology and mechanical and chemical impacts due to permafrost related conditions. The results of a literature review are always dependent on the available literature. Concerning permafrost there is some literature available from investigations in the field of long-term repositories and some from mining industries. However, reports of these investigations are few and the bulk of permafrost literature comes from the science departments concerned with surficial processes (e.g. geomorphology, hydrology, agriculture, etc) and from engineering concerns, such as foundation of constructions and pipeline design. This focus within the permafrost research inevitably yields a biased but also an abundant amount of information on localised surficial processes and a limited amount on regional and deep permafrost characteristics. Possible conclusions are that

  10. Summary of the Issues Regarding The Martian Subsurface Explorer

    Science.gov (United States)

    Eustes, A. W., III; Gertsch, L. S.; Lu, N.; Bridgford, E.; Tischler, A.; Stoner, M. S.; Wilcox, B. H.

    2000-01-01

    This is a summary of research work accomplished to date for the Jet Propulsion Laboratory by the Colorado School of Mines and the Michigan Technological University for the Martian Subsurface Explorer (SSX). The task involved a thorough review of the state of the art in drilling in the petroleum and mining industries in the following areas: 1) Drilling mechanics and energy requirements. 2) Sidewall friction in boreholes. 3) Rock property characteristics of basalt, permafrost, and ice. 4) Cuttings transport and recompaction of cuttings. and 5) Directional control at odd angle interfaces.

  11. Surface Modification and Surface - Subsurface Exchange Processes on Europa

    Science.gov (United States)

    Phillips, Cynthia B.; Molaro, Jamie; Hand, Kevin P.

    2017-10-01

    The surface of Jupiter’s moon Europa is modified by exogenic processes such as sputtering, gardening, radiolysis, sulfur ion implantation, and thermal processing, as well as endogenic processes including tidal shaking, mass wasting, and the effects of subsurface tectonic and perhaps cryovolcanic activity. New materials are created or deposited on the surface (radiolysis, micrometeorite impacts, sulfur ion implantation, cryovolcanic plume deposits), modified in place (thermal segregation, sintering), transported either vertically or horizontally (sputtering, gardening, mass wasting, tectonic and cryovolcanic activity), or lost from Europa completely (sputtering, plumes, larger impacts). Some of these processes vary spatially, as visible in Europa’s leading-trailing hemisphere brightness asymmetry.Endogenic geologic processes also vary spatially, depending on terrain type. The surface can be classified into general landform categories that include tectonic features (ridges, bands, cracks); disrupted “chaos-type” terrain (chaos blocks, matrix, domes, pits, spots); and impact craters (simple, complex, multi-ring). The spatial distribution of these terrain types is relatively random, with some differences in apex-antiapex cratering rates and latitudinal variation in chaos vs. tectonic features.In this work, we extrapolate surface processes and rates from the top meter of the surface in conjunction with global estimates of transport and resurfacing rates. We combine near-surface modification with an estimate of surface-subsurface (and vice versa) transport rates for various geologic terrains based on an average of proposed formation mechanisms, and a spatial distribution of each landform type over Europa’s surface area.Understanding the rates and mass balance for each of these processes, as well as their spatial and temporal variability, allows us to estimate surface - subsurface exchange rates over the average surface age (~50myr) of Europa. Quantifying the

  12. Campus Sewage Treatment in Multilayer Horizontal Subsurface Flow Constructed Wetlands

    DEFF Research Database (Denmark)

    Bai, Shaoyuan; Lyu, Tao; Ding, Yanli

    2017-01-01

    Horizontal subsurface flow constructed wetlands (HSCWs) are widely use for wastewater treatment. The objective of this study is to assess the effects of substrate-size selection and layout optimization on pollutant removal and microbial-community-distribution responses in HSCWs. Three pilot......-scale constructed wetlands (CWs) are established at Guilin University of Technology, China, to treat campus sewage. The three CWs include monolayer (CW1), three-layer (CW2), and six-layer (CW3) substrate structures with the hydraulic conductivity of the substrate increasing from the surface to the bottom...

  13. Estimation of subsurface thermal structure using sea surface height and sea surface temperature

    Science.gov (United States)

    Kang, Yong Q. (Inventor); Jo, Young-Heon (Inventor); Yan, Xiao-Hai (Inventor)

    2012-01-01

    A method of determining a subsurface temperature in a body of water is disclosed. The method includes obtaining surface temperature anomaly data and surface height anomaly data of the body of water for a region of interest, and also obtaining subsurface temperature anomaly data for the region of interest at a plurality of depths. The method further includes regressing the obtained surface temperature anomaly data and surface height anomaly data for the region of interest with the obtained subsurface temperature anomaly data for the plurality of depths to generate regression coefficients, estimating a subsurface temperature at one or more other depths for the region of interest based on the generated regression coefficients and outputting the estimated subsurface temperature at the one or more other depths. Using the estimated subsurface temperature, signal propagation times and trajectories of marine life in the body of water are determined.

  14. Impact of improved assimilation of temperature and salinity for coupled model seasonal forecasts

    Science.gov (United States)

    Zhao, Mei; Hendon, Harry H.; Alves, Oscar; Yin, Yonghong

    2014-05-01

    We assess the impact of improved ocean initial conditions for predicting El Niño-Southern Oscillation (ENSO) and Indian Ocean dipole (IOD) using the Bureau of Meteorology's Predictive Ocean Atmosphere Model for Australia (POAMA) coupled seasonal prediction model for the period 1982-2006. The new ocean initial conditions are provided by an ensemble-based analysis system that assimilates subsurface temperatures and salinity and which is a clear improvement over the previous optimal interpolation system which used static error covariances and was univariate (temperature only). Hindcasts using the new ocean initial conditions have better skill at predicting sea surface temperature (SST) variations associated with ENSO than do the hindcasts initialized with the old ocean analyses. The improvement derives from better prediction of subsurface temperatures and the largest improvements come during ENSO-IOD neutral years. We show that improved prediction of the Niño3.4 SST index derives from improved initial depiction of the thermocline and halocline in the equatorial Pacific but as lead time increases the improved depiction of the initial salinity field in the western Pacific become more important. Improved ocean initial conditions do not translate into improved skill for predicting the IOD but we do see an improvement in the prediction of subsurface temperatures in the Indian Ocean (IO). This result reflects that the coupling between subsurface and surface temperature variations is weaker in the IO than in the Pacific, but coupled model errors may also be limiting predictive skill in the IO.

  15. Performance Assessment of Subsurface Drip Irrigation System Using Pipes of Varying Flexibility

    OpenAIRE

    Talat Farid Ahmed; Hashim Nisar Hashmi; Abdul Razzaq Ghumman

    2011-01-01

    Subsurface drip irrigation method may play a significant role in overcoming the shortage of water particularly in arid regions. An experimental investigation was carried out to examine the efficiency of varying flexibility pipes installed in subsurface drip irrigation system. The study was also aimed to investigate the effect of subsurface drip irrigation on water requirement and yield of date palms. The testing was undertaken at Al- Qassim, Saudi Arabia. A considerable effe...

  16. An Evaluation of Subsurface Microbial Activity Conditional to Subsurface Temperature, Porosity, and Permeability at North American Carbon Sequestration Sites

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, B. [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States); National Energy Technology Lab. (NETL), Albany, OR (United States); Mordensky, S. [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States); National Energy Technology Lab. (NETL), Albany, OR (United States); Verba, Circe [National Energy Technology Lab. (NETL), Albany, OR (United States); Rabjohns, K. [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States); National Energy Technology Lab. (NETL), Albany, OR (United States); Colwell, F. [National Energy Technology Lab. (NETL), Albany, OR (United States); Oregon State Univ., Corvallis, OR (United States). College of Earth, Ocean, and Atmospheric Sciences

    2016-06-21

    Several nations, including the United States, recognize global climate change as a force transforming the global ecosphere. Carbon dioxide (CO2) is a greenhouse gas that contributes to the evolving climate. Reduction of atmospheric CO2 levels is a goal for many nations and carbon sequestration which traps CO2 in the Earth’s subsurface is one method to reduce atmospheric CO2 levels. Among the variables that must be considered in developing this technology to a national scale is microbial activity. Microbial activity or biomass can change rock permeability, alter artificial seals around boreholes, and play a key role in biogeochemistry and accordingly may determine how CO2 is sequestered underground. Certain physical parameters of a reservoir found in literature (e.g., temperature, porosity, and permeability) may indicate whether a reservoir can host microbial communities. In order to estimate which subsurface formations may host microbes, this report examines the subsurface temperature, porosity, and permeability of underground rock formations that have high potential to be targeted for CO2 sequestration. Of the 268 North American wellbore locations from the National Carbon Sequestration Database (NATCARB; National Energy and Technology Laboratory, 2015) and 35 sites from Nelson and Kibler (2003), 96 sequestration sites contain temperature data. Of these 96 sites, 36 sites have temperatures that would be favorable for microbial survival, 48 sites have mixed conditions for supporting microbial populations, and 11 sites would appear to be unfavorable to support microbial populations. Future studies of microbe viability would benefit from a larger database with more formation parameters (e.g. mineralogy, structure, and groundwater chemistry), which would help to increase understanding of where CO2 sequestration could be most efficiently implemented.

  17. Subsurface Ocean Signals from an Orbiting Polarization Lidar

    Directory of Open Access Journals (Sweden)

    Xiaomei Lu

    2013-07-01

    Full Text Available Detection of subsurface returns from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO satellite were demonstrated. Despite the coarse range resolution of this aerosol lidar, evidence of subsurface scattering was observed as a delay and broadening of the cross-polarized signal relative to the co-polarized signal in the three near-surface range bins. These two effects contributed to an increased depolarization at the nominal depth of 25 m. These features were all correlated with near-surface chlorophyll concentrations. An increase in the depolarization was also seen at a depth of 50 m under certain conditions, suggesting that chlorophyll concentration at that depth could be estimated if an appropriate retrieval technique can be developed. At greater depths, the signal is dominated by the temporal response of the detectors, which was approximated by an analytical expression. The depolarization caused by aerosols in the atmosphere was calculated and eliminated as a possible artifact.

  18. Mapping the Upper Subsurface of MARS Using Radar Polarimetry

    Science.gov (United States)

    Carter, L. M.; Rincon, R.; Berkoski, L.

    2012-01-01

    Future human exploration of Mars will require detailed knowledge of the surface and upper several meters of the subsurface in potential landing sites. Likewise, many of the Planetary Science Decadal Survey science goals, such as understanding the history of Mars climate change, determining how the surface was altered through processes like volcanism and fluvial activity, and locating regions that may have been hospitable to life in the past, would be significantly advanced through mapping of the upper meters of the surface. Synthetic aperture radar (SAR) is the only remote sensing technique capable of penetrating through meters of material and imaging buried surfaces at high (meters to tens-of-meters) spatial resolution. SAR is capable of mapping the boundaries of buried units and radar polarimetry can provide quantitative information about the roughness of surface and subsurface units, depth of burial of stratigraphic units, and density of materials. Orbital SAR systems can obtain broad coverage at a spatial scale relevant to human and robotic surface operations. A polarimetric SAR system would greatly increase the safety and utility of future landed systems including sample caching.

  19. Subsurface temperature distribution in a tropical alluvial fan

    Science.gov (United States)

    Chen, Wenfu; Chang, Minhsiang; Chen, Juier; Lu, Wanchung; Huang, Chihc; Wang, Yunshuen

    2017-04-01

    As a groundwater intensive use country, Taiwan's 1/3 water supplies are derived from groundwater. The major aquifers consist of sand and gravel formed in alluvial fans which border the fronts of central mountains. Thanks to high density of monitoring wells which provide a window to see the details of the subsurface temperature distribution and the thermal regime in an alluvial fan system. Our study area, the Choshui Alluvial Fan, is the largest groundwater basin in Taiwan and, located within an area of 2,000 km2, has a population of over 1.5 million. For this work, we investigated temperature-depth profiles using 70 groundwater monitoring wells during 2000 to 2015. Our results show that the distribution of subsurface temperature is influenced by various factors such as groundwater recharge, groundwater flow field, air temperature and land use. The groundwater recharge zone, hills to the upper fan, contains disturbed and smaller geothermal gradients. The lack of clay layers within the upper fan aquifers and fractures that developed in the hills should cause the convection and mixing of cooler recharge water to groundwater, resulting in smaller geothermal gradients. The groundwater temperatures at a depth to 300 m within the upper fan and hill were approximately only 23-24 °C while the current mean ground surface temperature is approximately 26 °C.

  20. Supercontinuum Light Sources for Hyperspectral Subsurface Laser Scattering

    DEFF Research Database (Denmark)

    Nielsen, Otto Højager Attermann; Dahl, Anders Lindbjerg; Larsen, Rasmus

    2011-01-01

    A materials structural and chemical composition influences its optical scattering properties. In this paper we investigate the use of subsurface laser scattering (SLS) for inferring structural and chemical information of food products. We have constructed a computer vision system based on a super......A materials structural and chemical composition influences its optical scattering properties. In this paper we investigate the use of subsurface laser scattering (SLS) for inferring structural and chemical information of food products. We have constructed a computer vision system based...... on a supercontinuum laser light source and an Acousto- Optic Tunable Filter (AOTF) to provide a collimated light source, which can be tuned to any wavelength in the range from 480 to 900 nm. We present the newly developed hyperspectral vision system together with a proof-of-principle study of its ability...... to discriminate between dairy products with either similar chemical or structural composition. The combined vision system is a new way for industrial food inspection allowing non-intrusive online process inspection of parameters that is hard with existing technology....

  1. Liquid Water in the Extremely Shallow Martian Subsurface

    Science.gov (United States)

    Pavlov, A.; Shivak, J. N.

    2012-01-01

    Availability of liquid water is one of the major constraints for the potential Martian biosphere. Although liquid water is unstable on the surface of Mars due to low atmospheric pressures, it has been suggested that liquid films of water could be present in the Martian soil. Here we explored a possibility of the liquid water formation in the extremely shallow (1-3 cm) subsurface layer under low atmospheric pressures (0.1-10 mbar) and low ("Martian") surface temperatures (approx.-50 C-0 C). We used a new Goddard Martian simulation chamber to demonstrate that even in the clean frozen soil with temperatures as low as -25C the amount of mobile water can reach several percents. We also showed that during brief periods of simulated daylight warming the shallow subsurface ice sublimates, the water vapor diffuses through porous surface layer of soil temporarily producing supersaturated conditions in the soil, which leads to the formation of additional liquid water. Our results suggest that despite cold temperatures and low atmospheric pressures, Martian soil just several cm below the surface can be habitable.

  2. Scanning array radar system for bridge subsurface imaging

    Science.gov (United States)

    Lai, Chieh-Ping; Ren, Yu-Jiun; Yu, Tzu Yang

    2012-04-01

    Early damage detection of bridge has been an important issue for modern civil engineering technique. Existing bridge inspection techniques used by State Department of Transportation (DOT) and County DOT include visual inspection, mechanical sounding, rebound hammer, cover meter, electrical potential measurements, and ultrasonics; other NDE techniques include ground penetrating radar (GPR), radiography, and some experimental types of sensors. Radar technology like GPR has been widely used for the bridge structure detection with a good penetration depth using microwave energy. The system to be presented in this paper is a different type of microwave sensing technology. It is focus on the subsurface detection and trying to find out detail information at subsurface (10 cm) with high resolution radar imaging from a flexible standoff distance. Our radar operating frequency is from 8-12 GHz, which is different from most of the current GPR systems. Scanning array antenna system is designed for adjustable beamwidth, preferable scanning area, and low sidelobe level. From the theoretical analysis and experimental results, it is found that the proposed technique can successfully capture the presence of the near-surface anomaly. This system is part of our Multi- Modal Remote Sensing System (MRSS) and provides good imaging correlations with other MRSS sensors.

  3. Compositional Simulation of Subsurface Remediation via Density Modified Displacement

    Science.gov (United States)

    Phelan, T. J.; Ramsburg, C. A.; Abriola, L. M.

    2004-12-01

    Reduced interfacial tension displacement of nonaqueous phase liquids (NAPLs) in the subsurface can be an efficient means of remediating contaminant source zones. Application of technologies based upon this principle, however, is problematic for NAPLs that are denser than water (DNAPLs) due to their tendency to sink further into the subsurface when mobilized. Pre-mobilization density conversion via alcohol partitioning has been suggested as a means of overcoming this problem. This presentation details efforts in the mathematical modeling of this proposed technology. A comprehensive, empirically-based, multiphase flow and transport model which incorporates the ternary phase partitioning behavior of the DNAPL-alcohol-water system and compositionally dependent phase (e.g., density and viscosity) and interfacial properties (i.e., interfacial tension, capillary pressure-saturation and relative permeability relationships, NAPL entrapment behavior) is described. Model simulations of bench-scale laboratory experiments examining the density conversion and mobilization of entrapped trichloroethene with n-butanol are presented. These results demonstrate the compositional model's ability to accurately describe the density modified displacement process. Sensitivity of model predictions to different physicochemical processes is highlighted.

  4. Operational mapping of the DWH deep subsurface dispersed oil

    Science.gov (United States)

    Seim, Harvey E.; Crout, Richard; Rice, Glen

    2011-06-01

    Mapping of the deep dispersed oil feature from the blowout of the MC252 wellhead was organized by the subsurface mapping unit within the Unified Area Command starting in early August, 2010. The operational process employed and the challenge presented by the response situation are reviewed. Colored dissolved organic matter fluorescence, used to establish existence of the subsurface oil prior to this time, had largely fallen below background levels for the sensors by this time. Dissolved oxygen (DO), deficits in which were assumed to be related to consumption of oil by microbes, was the only routinely observed variable in vertical profiles that displayed a persistent and obvious anomaly. The DO anomaly was therefore used to identify the presence and magnitude of the dispersed oil impact. An adaptive sampling plan employing daily review of DO profiles to provide vessel guidance was established and permitted a coarse mapping of the feature within 4 weeks. The DO anomaly extended from the wellhead to the WSW for more than 350 km, bounded to the north by the upper slope (approximately 1000 m isobath), with a cross-slope extent of 60-100 km, and was also present to the ENE of the wellhead out to 60 km.

  5. Subsurface structure around Fukuoka using borhole data, Japan

    Science.gov (United States)

    Kitada, N.; Tanaka, R.; Inoue, N.; Watanabe, K.

    2014-12-01

    Fukuoka is located in the Kyushu area, southwest Japan. In 1999, Fukuokaken Seiho earthquake was occurred and damaged much lifeline and construction. Source fault of this earthquake is the same trend of Kego fault. Kego fault is one of the strike slip fault. This fault activity has a great deal to do with the history of Fukuoka plain. This research is funded by the integrated research project for the Uemachi active fault system in FY2011 by MEXT. However, detail of Kego fault are not make clear, therefore, from 2011to 2013, the integrated research project for the Kego active fault system by MEXT were carried out. In this project, we are corrected geotechnical borehole data, and make subsurface model for strong motion analysis. Geotechnical borehole data such as preparation of construction are collected over 17000 data. Especially, more than 12000 borehole data were collected in the Fukuoka plain. Although Kego fault is the strike slip fault; we can observe vertical displacement in the plain. Shimoyama et al (2005) were carried out of the geological boring survey along Kego fault at Yakuin area. The result of this study, the maximum vertical displacement of Kego fault in the plain is about 50m at the top of the basement rock. We used these geological information for understanding of geotechnical borehole data. The result of this study, the displacement of Kego fault on the top of basement rock can recognized from Uminonakamichi to Shimodairi. Subsurface model make each 250m mesh are reproducibly-observed.

  6. Subsurface plasma in beam of continuous CO2-laser

    Science.gov (United States)

    Danytsikov, Y. V.; Dymshakov, V. A.; Lebedev, F. V.; Pismennyy, V. D.; Ryazanov, A. V.

    1986-03-01

    Experiments performed at the Institute of Atomic Energy established the conditions for formation of subsurface plasma in substances by laser radiation and its characteristics. A quasi-continuous CO2 laser emitting square pulses of 0.1 to 1.0 ms duration and 1 to 10 kW power as well as a continuous CO2 laser served as radiation sources. Radiation was focused on spots 0.1 to 0.5 mm in diameter and maintained at levels ensuring constant power density during the interaction time, while the temperature of the target surface was measured continuously. Metals, graphite and dielectric materials were tested with laser action taking place in air N2 + O2 mixtures, Ar or He atmosphere under pressures of 0.01 to 1.0 atm. Data on radiation intensity thresholds for evaporation and plasma formation were obtained. On the basis of these thresholds, combined with data on energy balance and the temperature profile in plasma layers, a universal state diagram was constructed for subsurface plasma with nonquantified surface temperature and radiation intensity coordinates.

  7. Anaerobic hydrocarbon biodegradation in deep subsurface oil reservoirs.

    Science.gov (United States)

    Aitken, Carolyn M; Jones, D M; Larter, S R

    2004-09-16

    Biodegradation of crude oil in subsurface petroleum reservoirs is an important alteration process with major economic consequences. Aerobic degradation of petroleum hydrocarbons at the surface is well documented and it has long been thought that the flow of oxygen- and nutrient-bearing meteoric waters into reservoirs was necessary for in-reservoir petroleum biodegradation. The occurrence of biodegraded oils in reservoirs where aerobic conditions are unlikely, together with the identification of several anaerobic microorganisms in oil fields and the discovery of anaerobic hydrocarbon biodegradation mechanisms, suggests that anaerobic degradation processes could also be responsible. The extent of anaerobic hydrocarbon degradation processes in the world's deep petroleum reservoirs, however, remains strongly contested. Moreover, no organism has yet been isolated that has been shown to degrade hydrocarbons under the conditions found in deep petroleum reservoirs. Here we report the isolation of metabolites indicative of anaerobic hydrocarbon degradation from a large fraction of 77 degraded oil samples from both marine and lacustrine sources from around the world, including the volumetrically important Canadian tar sands. Our results therefore suggest that anaerobic hydrocarbon degradation is a common process in biodegraded subsurface oil reservoirs.

  8. A fully subordinated linear flow model for hillslope subsurface stormflow

    Science.gov (United States)

    Zhang, Yong; Baeumer, Boris; Chen, Li; Reeves, Donald M.; Sun, HongGuang

    2017-04-01

    Hillslope subsurface stormflow exhibits complex patterns when natural soils with multiscale heterogeneity impart a spatiotemporally nonlocal memory on flow dynamics. To efficiently quantify such nonlocal flow responses, this technical note proposes a fully subordinated flow (FSF) equation where the time- and flow-subordination capture the temporal and spatial memory, respectively. Results show that the time-subordination component of the FSF model captures a wide range of delayed flow response due to various degrees of soil heterogeneity (especially for low-conductivity zones), while the model's flow-subordination term accounts for the rapid flow responses along preferential flow paths. In the FSF model, parameters defining spatiotemporal memory functions may be related to soil properties, while other parameters such as scalar factors controlling the overall advection and diffusion are difficult to predict and can be estimated from subsurface stormflow hydrographs. These parameters can be constants at the hillslope scale because the spatiotemporal subordination, an upscaling technique, can capture the impact of system heterogeneity on flow dynamics, leading to a linear FSF model that might be applicable for various slopes. Valid scale, limitation and extension of the FSF model, and modification of the model for other complex hydrological dynamics are also discussed.

  9. Using electrical resistance tomography to map subsurface temperatures

    Science.gov (United States)

    Ramirez, Abelardo L.; Chesnut, Dwayne A.; Daily, William D.

    1994-01-01

    A method is provided for measuring subsurface soil or rock temperatures remotely using electrical resistivity tomography (ERT). Electrical resistivity measurements are made using electrodes implanted in boreholes driven into the soil and/or at the ground surface. The measurements are repeated as some process changes the temperatures of the soil mass/rock mass. Tomographs of electrical resistivity are calculated based on the measurements using Poisson's equation. Changes in the soil/rock resistivity can be related to changes in soil/rock temperatures when: (1) the electrical conductivity of the fluid trapped in the soil's pore space is low, (2) the soil/rock has a high cation exchange capacity and (3) the temperature changes are sufficiently high. When these three conditions exist the resistivity changes observed in the ERT tomographs can be directly attributed to changes in soil/rock temperatures. This method provides a way of mapping temperature changes in subsurface soils remotely. Distances over which the ERT method can be used to monitor changes in soil temperature range from tens to hundreds of meters from the electrode locations.

  10. Subsurface imaging of two-dimensional materials at the nanoscale

    Science.gov (United States)

    Dinelli, Franco; Pingue, Pasqualantonio; Kay, Nicholas D.; Kolosov, Oleg V.

    2017-02-01

    Scanning probe microscopy (SPM) represents a powerful tool that, in the past 30 years, has allowed for the investigation of material surfaces in unprecedented ways at the nanoscale level. However, SPM has shown very little capability for depth penetration, which several nanotechnology applications require. Subsurface imaging has been achieved only in a few cases, when subsurface features influence the physical properties of the surface, such as the electronic states or the heat transfer. Ultrasonic force microscopy (UFM), an adaption of the contact mode atomic force microscopy, can dynamically measure the stiffness of the elastic contact between the probing tip and the sample surface. In particular, UFM has proven highly sensitive to the near-surface elastic field in non-homogeneous samples. In this paper, we present an investigation of two-dimensional (2D) materials, namely flakes of graphite and molybdenum disulphide placed on structured polymeric substrates. We show that UFM can non-destructively distinguish suspended and supported areas and localise defects, such as buckling or delamination of adjacent monolayers, generated by residual stress. Specifically, UFM can probe small variations in the local indentation induced by the mechanical interaction between the tip and the sample. Therefore, any change in the elastic modulus within the volume perturbed by the applied load or the flexural bending of the suspended areas can be detected and imaged. These investigation capabilities are very promising in order to study the buried interfaces of nanostructured 2D materials such as in graphene-based devices.

  11. Efficiency of subsurface flow constructed wetland with trickling filter.

    Science.gov (United States)

    Vucinic, Aleksandra Anic; Hrenovic, Jasna; Tepes, Predrag

    2012-06-01

    Effective wastewater purification in subsurface flow constructed wetlands must include adequate pretreatment and ensure a sufficient amount of dissolved oxygen. In a pilot-scale operation, a subsurface flow constructed wetland (CW) consisted of a primary settlement tank, a trickling filter for pretreatment and two serially assembled basins. The trickling filter was added to ensure sufficient aeration, increase purification of the wastewater and shorten the wastewater purification time. The estimated nominal flow was 0.7 m3/d. The experiments were conducted using the wastewater from the municipal sewage canal of the city of Zagreb, with utilization of three different flows: 0.72 (A), 1.44 (B) and 2.88 (C) m3/d. The efficiency of the purification process was monitored over a period of three years (TSS, BOD5, COD, NH4-N, NO2-N, PO4-P, dissolved oxygen, temperature and pH). The experimental results showed an increase in the removal efficiency with a doubling of the nominal flow from 0.7 to 1.44 m3/d, which could be related to the implementation of the trickling filter where high removal rates were achieved.

  12. Subsurface barrier validation with the SEAtrace{trademark} system

    Energy Technology Data Exchange (ETDEWEB)

    Sandra Dalvit Dunn; William Lowry; Veraun Chipman

    1999-09-01

    Under contract to the Department of Energy, Science and Engineering Associates has completed development and testing of a subsurface barrier verification and monitoring system. This system, called SEAtrace{trademark}, is able to locate and size leaks with a high degree of accuracy in subsurface barriers that are emplaced in an unsaturated medium. It uses gaseous tracer injection, in-field real-time monitoring, and real time data analysis to evaluate barrier integrity. The approach is: Conservative as it measures vapor leaks in a containment system whose greatest risk is posed by liquid leaks; Applicable to any impermeable type of barrier emplacement technology in the unsaturated zone; Inexpensive as it uses readily available, non-toxic, nonhazardous gaseous tracers, does not require an inordinately large number of sampling points, and injection and sampling points can be emplaced by direct push techniques; Capable of assessing not only a barrier's initial integrity, but can also provide long-term monitoring. To date, six demonstrations of the system have been completed. Results from two of the demonstrations are detailed in this report. They include the final developmental demonstration of the SEAtrace system and a comparison demonstration of two tracer based verification technologies. The final developmental demonstration of SEAtrace was completed at a naval facility in Brunswick, Maine. The demonstration was funded solely by the DOE and was performed in cooperation with the US Navy, the Environmental Protection Agency, and the Maine Department of Environmental Protection.

  13. Detection of sub-surface crack in railway wheel using a new sensing system

    Science.gov (United States)

    Kwon, S. J.; Seo, J. W.; Lee, D. H.; You, W. J.

    2011-04-01

    To evaluate wheel defect, it is necessary to develop a new NDT on railway wheel. Unlikely a conventional NDT system, the NDT system of the present paper can detect a sub-surface crack. In the present paper, the new NDT method is applied to the detection of surface and sub-surface crack defects for railway wheels. To detect the defects for railway wheels, the sensor for new NDT is optimized and the tests are carried out with respect to sub-surface defects respectively. The result shows that the surface crack as well as sub-surface crack could be detected by using new NDT method.

  14. Subsurface Access, Characterization, Acquisition, Transport, Storage and Delivery in Microgravity Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will develop geotechnical measurements, sample extraction and transport equipment for subsurface regolith on NEOs, asteroids, moons and planets,...

  15. Performance of a vertical subsurface flow constructed wetland under different operational conditions

    National Research Council Canada - National Science Library

    Abdelhakeem, Sara G; Aboulroos, Samir A; Kamel, Mohamed M

    2016-01-01

    The performance of a vertical subsurface flow constructed wetland (VSSFCW) for sewage effluent treatment was studied in an eight month experiment under different operational conditions including: vegetation...

  16. Nutritive and photosynthetic ecology of subsurface chlorophyll maxima in Canadian Arctic waters

    Directory of Open Access Journals (Sweden)

    J. Martin

    2012-12-01

    Full Text Available Assessments of carbon and nitrogen (N assimilation in Canadian Arctic waters confirmed the large contribution of subsurface chlorophyll maxima (SCM to total water-column production from spring to late fall. Although SCM communities showed acclimation to low irradiance and greater nitrate (NO3 availability, their productivity was generally constrained by light and temperature. During spring–early summer, most of the primary production at the SCM was sustained by NO3, with an average f-ratio (i.e., relative contribution of NO3 uptake to total N uptake of 0.74 ± 0.26. The seasonal decrease in NO3 availability and irradiance, coupled to the build up of ammonium (NH4+, favoured a transition toward a predominantly regenerative system (f-ratio = 0.37 ± 0.20 during late summer and fall. Results emphasize the need to adequately consider SCM when estimating primary production and to revisit ecosystem model parameters in highly stratified Arctic waters.

  17. Eruptions at Lone Star geyser, Yellowstone National Park, USA: 2. Constraints on subsurface dynamics

    Science.gov (United States)

    Vandemeulebrouck, Jean; Sohn, Robert A.; Rudolph, Maxwell L.; Hurwitz, Shaul; Manga, Michael; Johnston, Malcolm J.S.; Soule, S. Adam; McPhee, Darcy K.; Glen, Jonathan M.G.; Karlstrom, Leif; Murphy, Fred

    2014-01-01

    We use seismic, tilt, lidar, thermal, and gravity data from 32 consecutive eruption cycles of Lone Star geyser in Yellowstone National Park to identify key subsurface processes throughout the geyser's eruption cycle. Previously, we described measurements and analyses associated with the geyser's erupting jet dynamics. Here we show that seismicity is dominated by hydrothermal tremor (~5–40 Hz) attributed to the nucleation and/or collapse of vapor bubbles. Water discharge during eruption preplay triggers high-amplitude tremor pulses from a back azimuth aligned with the geyser cone, but during the rest of the eruption cycle it is shifted to the east-northeast. Moreover, ~4 min period ground surface displacements recur every 26 ± 8 min and are uncorrelated with the eruption cycle. Based on these observations, we conclude that (1) the dynamical behavior of the geyser is controlled by the thermo-mechanical coupling between the geyser conduit and a laterally offset reservoir periodically filled with a highly compressible two-phase mixture, (2) liquid and steam slugs periodically ascend into the shallow crust near the geyser system inducing detectable deformation, (3) eruptions occur when the pressure decrease associated with overflow from geyser conduit during preplay triggers an unstable feedback between vapor generation (cavitation) and mass discharge, and (4) flow choking at a constriction in the conduit arrests the runaway process and increases the saturated vapor pressure in the reservoir by a factor of ~10 during eruptions.

  18. Modeling and analysis of sub-surface leakage current in nano-MOSFET under cutoff regime

    Science.gov (United States)

    Swami, Yashu; Rai, Sanjeev

    2017-02-01

    The high leakage current in nano-meter regimes is becoming a significant portion of power dissipation in nano-MOSFET circuits as threshold voltage, channel length, and gate oxide thickness are scaled down to nano-meter range. Precise leakage current valuation and meticulous modeling of the same at nano-meter technology scale is an increasingly a critical work in designing the low power nano-MOSFET circuits. We present a specific compact model for sub-threshold regime leakage current in bulk driven nano-MOSFETs. The proposed logical model is instigated and executed into the latest updated PTM bulk nano-MOSFET model and is found to be in decent accord with technology-CAD simulation data. This paper also reviews various transistor intrinsic leakage mechanisms for nano-MOSFET exclusively in weak inversion, like drain-induced barricade lowering (DIBL), gate-induced drain leakage (GIDL), gate oxide tunneling (GOT) leakage etc. The root cause of the sub-surface leakage current is mainly due to the nano-scale short channel length causing source-drain coupling even in sub-threshold domain. Consequences leading to carriers triumphing the barricade between the source and drain. The enhanced model effectively considers the following parameter dependence in the account for better-quality value-added results like drain-to-source bias (VDS), gate-to-source bias (VGS), channel length (LG), source/drain junction depth (Xj), bulk doping concentration (NBULK), and operating temperature (Top).

  19. EMSL Geochemistry, Biogeochemistry and Subsurface Science-Science Theme Advisory Panel Meeting

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Gordon E.; Chaka, Anne; Shuh, David K.; Roden, Eric E.; Werth, Charles J.; Hess, Nancy J.; Felmy, Andrew R.; Rosso, Kevin M.; Baer, Donald R.; Bailey, Vanessa L.; Bowden, Mark E.; Grate, Jay W.; Hoyt, David W.; Kuprat, Laura R.; Lea, Alan S.; Mueller, Karl T.; Oostrom, Martinus; Orr, Galya; Pasa-Tolic, Ljiljana; Plata, Charity; Robinson, E. W.; Teller, Raymond G.; Thevuthasan, Suntharampillai; Wang, Hongfei; Wiley, H. S.; Wilkins, Michael J.

    2011-08-01

    This report covers the topics of discussion and the recommendations of the panel members. On December 8 and 9, 2010, the Geochemistry, Biogeochemistry, and Subsurface Science (GBSS) Science Theme Advisory Panel (STAP) convened for a more in-depth exploration of the five Science Theme focus areas developed at a similar meeting held in 2009. The goal for the fiscal year (FY) 2011 meeting was to identify potential topical areas for science campaigns, necessary experimental development needs, and scientific members for potential research teams. After a review of the current science in each of the five focus areas, the 2010 STAP discussions successfully led to the identification of one well focused campaign idea in pore-scale modeling and five longer-term potential research campaign ideas that would likely require additional workshops to identify specific research thrusts. These five campaign areas can be grouped into two categories: (1) the application of advanced high-resolution, high mass accuracy experimental techniques to elucidate the interplay between geochemistry and microbial communities in terrestrial ecosystems and (2) coupled computation/experimental investigations of the electron transfer reactions either between mineral surfaces and outer membranes of microbial cells or between the outer and inner membranes of microbial cells.

  20. MSTS Multiphase Subsurface Transport Simulator User's Guide and Reference

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, W.E.; White, M.D.

    1993-05-01

    This User's Guide and Reference provides information and instructions on the use of the Multiphase Subsurface Transport Simulator (MSTS) code and the associated MSTS Graphical Input. The MSTS code is used to simulate water flow, air flow, heat transfer, and dilute species mass transport in variably saturated geologic media for one, two, or three dimensions using an integrated finite-difference numerical scheme. Any or all of these processes may be simulated in a fully coupled manner. MSTS is a two-phase, two-component code with secondary processes that include binary diffusion and vapor pressure lowering. The geologic media may be homogeneous or heterogeneous, isotropic or anisotropic, and unfractured or highly fractured. A problem geometry may be described by either Cartesian or cylindrical coordinates. MSTS is written in FORTRAN 77, following the American National Standards Institute (ANSI) standards, and is machine-independent with the exception of some time and date calls required for quality control (provisions are made in the code for relatively easy adoption to a number of machines for these calls).

  1. MSTS. Multiphase Subsurface Transport Simulator User`s Guide and Reference

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, W.E.; White, M.D.

    1993-05-01

    This User`s Guide and Reference provides information and instructions on the use of the Multiphase Subsurface Transport Simulator (MSTS) code and the associated MSTS Graphical Input. The MSTS code is used to simulate water flow, air flow, heat transfer, and dilute species mass transport in variably saturated geologic media for one, two, or three dimensions using an integrated finite-difference numerical scheme. Any or all of these processes may be simulated in a fully coupled manner. MSTS is a two-phase, two-component code with secondary processes that include binary diffusion and vapor pressure lowering. The geologic media may be homogeneous or heterogeneous, isotropic or anisotropic, and unfractured or highly fractured. A problem geometry may be described by either Cartesian or cylindrical coordinates. MSTS is written in FORTRAN 77, following the American National Standards Institute (ANSI) standards, and is machine-independent with the exception of some time and date calls required for quality control (provisions are made in the code for relatively easy adoption to a number of machines for these calls).

  2. Eruptions at Lone Star geyser, Yellowstone National Park, USA: 2. Constraints on subsurface dynamics

    Science.gov (United States)

    Vandemeulebrouck, Jean; Sohn, Robert A.; Rudolph, Maxwell L.; Hurwitz, Shaul; Manga, Michael; Johnston, Malcolm J. S.; Soule, S. Adam; McPhee, Darcy; Glen, Jonathan M. G.; Karlstrom, Leif; Murphy, Fred

    2014-12-01

    We use seismic, tilt, lidar, thermal, and gravity data from 32 consecutive eruption cycles of Lone Star geyser in Yellowstone National Park to identify key subsurface processes throughout the geyser's eruption cycle. Previously, we described measurements and analyses associated with the geyser's erupting jet dynamics. Here we show that seismicity is dominated by hydrothermal tremor (~5-40 Hz) attributed to the nucleation and/or collapse of vapor bubbles. Water discharge during eruption preplay triggers high-amplitude tremor pulses from a back azimuth aligned with the geyser cone, but during the rest of the eruption cycle it is shifted to the east-northeast. Moreover, ~4 min period ground surface displacements recur every 26 ± 8 min and are uncorrelated with the eruption cycle. Based on these observations, we conclude that (1) the dynamical behavior of the geyser is controlled by the thermo-mechanical coupling between the geyser conduit and a laterally offset reservoir periodically filled with a highly compressible two-phase mixture, (2) liquid and steam slugs periodically ascend into the shallow crust near the geyser system inducing detectable deformation, (3) eruptions occur when the pressure decrease associated with overflow from geyser conduit during preplay triggers an unstable feedback between vapor generation (cavitation) and mass discharge, and (4) flow choking at a constriction in the conduit arrests the runaway process and increases the saturated vapor pressure in the reservoir by a factor of ~10 during eruptions.

  3. Debates—Stochastic subsurface hydrology from theory to practice: Does stochastic subsurface hydrology help solving practical problems of contaminant hydrogeology?

    Science.gov (United States)

    Cirpka, Olaf A.; Valocchi, Albert J.

    2016-12-01

    While stochastic subsurface hydrology has been tremendously successful in understanding how the spatial variability of hydraulic conductivity affects conservative solute transport in idealized settings, it has gained little impact in practice. This is the case because typical assumptions needed for the derivation of analytical expressions are too restrictive for practical applications and often geologically implausible, small-scale variation of hydraulic conductivity is by far not the only cause of uncertainty when considering the fate and remediation of pollutants, and the research community has not developed enough methods that can directly be used by practitioners. To overcome these shortcomings, we propose putting more emphasis on providing easy-to-use tools to generate realistic realizations of subsurface properties that are conditioned on all data measured at a site, extending the focus from hydraulic conductivity only to all parameters and processes relevant for reactive transport, making use of self-organizing principles of reactive transport to conceptually simplify the problem, and addressing conceptual uncertainty by stochastic methods.

  4. Sub-surface terahertz imaging through uneven surfaces: visualizing Neolithic wall paintings in Çatalhöyük.

    Science.gov (United States)

    Walker, Gillian C; Bowen, John W; Matthews, Wendy; Roychowdhury, Soumali; Labaune, Julien; Mourou, Gerard; Menu, Michel; Hodder, Ian; Jackson, J Bianca

    2013-04-08

    Pulsed terahertz imaging is being developed as a technique to image obscured mural paintings. Due to significant advances in terahertz technology, portable systems are now capable of operating in unregulated environments and this has prompted their use on archaeological excavations. August 2011 saw the first use of pulsed terahertz imaging at the archaeological site of Çatalhöyük, Turkey, where mural paintings dating from the Neolithic period are continuously being uncovered by archaeologists. In these particular paintings the paint is applied onto an uneven surface, and then covered by an equally uneven surface. Traditional terahertz data analysis has proven unsuccessful at sub-surface imaging of these paintings due to the effect of these uneven surfaces. For the first time, an image processing technique is presented, based around Gaussian beam-mode coupling, which enables the visualization of the obscured painting.

  5. Deep subsurface cavities in skin utilizing mechanical optical clearing and femtosecond laser ablation.

    Science.gov (United States)

    Qiu, Jinze; Neev, Joseph; Wang, Tianyi; Milner, Thomas E

    2013-08-01

    High precision subsurface ablation can be produced in transparent materials using femtosecond laser pulses and multiphoton absorption. Light scattering limits application of the same technique to most biological tissues. Previously, subsurface ablation was demonstrated at superficial depths (50-250 µm) in highly scattering tissues including murine skin and human sclera. We report application of mechanical optical clearing to produce deeper subsurface femtosecond ablation in rodent skin. Ability to target deeper structures in skin using subsurface ablation may allow novel clinical applications for dermatological laser surgery. Operation of a prototype tissue optical clearing device (TOCD) was verified with white light photography in ex vivo rodent skin. A focused femtosecond beam transmitted through the TOCD and was scanned across rodent skin to produce subsurface ablation at increasing focal depths. Histological sections with H&E staining of the laser irradiated rodent skin were examined for subsurface ablation features following laser irradiation. Subsurface cavities were observed as deep as 1.7 mm below the skin surface in histological tissue sections. Diameter of subsurface cavities varied from tens of microns to over 100 μm. Subsurface cavities produced by scanning the focused femtosecond beam were contiguous and formed a continuous cut. Mechanical disruption of the overlying tissues was not observed. Mechanical optical clearing can be applied directly to in situ rodent skin and produces an optical clearing effect. High precision subsurface ablation can be produced at positions substantially deeper than previously demonstrated. Future studies may be targeted in in vivo human skin to investigate potential clinical applications of subsurface femtosecond ablation using mechanical optical clearing. Copyright © 2013 Wiley Periodicals, Inc.

  6. Examining Changes in Radioxenon Isotope Activity Ratios during Subsurface Transport

    Science.gov (United States)

    Annewandter, Robert

    2014-05-01

    The Non-Proliferation Experiment (NPE) has demonstrated and modelled the usefulness of barometric pumping induced gas transport and subsequent soil gas sampling during On-Site inspections. Generally, gas transport has been widely studied with different numerical codes. However, gas transport of radioxenons and radioiodines in the post-detonation regime and their possible fractionation is still neglected in the open peer-reviewed literature. Atmospheric concentrations of the radioxenons Xe-135, Xe-133m, Xe-133 and Xe-131m can be used to discriminate between civilian releases (nuclear power plants or medical isotope facilities), and nuclear explosion sources. It is based on the multiple isotopic activity ratio method. Yet it is not clear whether subsurface migration of the radionuclides, with eventual release into the atmosphere, can affect the activity ratios due to fractionation. Fractionation can be caused by different mass diffusivities due to mass differences between the radionuclides. Cyclical changes in atmospheric pressure can drive subsurface gas transport. This barometric pumping phenomenon causes an oscillatoric flow in upward trending fractures or highly conductive faults which, combined with diffusion into the porous matrix, leads to a net transport of gaseous components - a so-called ratcheting effect. We use a general purpose reservoir simulator (Complex System Modelling Platform, CSMP++) which is recognized by the oil industry as leading in Discrete Fracture-Matrix (DFM) simulations. It has been applied in a range of fields such as deep geothermal systems, three-phase black oil simulations, fracture propagation in fractured, porous media, and Navier-Stokes pore-scale modelling among others. It is specifically designed to account for structurally complex geologic situation of fractured, porous media. Parabolic differential equations are solved by a continuous Galerkin finite-element method, hyperbolic differential equations by a complementary finite

  7. Subsurface Flow Modeling in Single and Dual Continuum Anisotropic Porous Media using the Multipoint Flux Approximation Method

    KAUST Repository

    Negara, Ardiansyah

    2015-05-01

    Anisotropy of hydraulic properties of the subsurface geologic formations is an essential feature that has been established as a consequence of the different geologic processes that undergo during the longer geologic time scale. With respect to subsurface reservoirs, in many cases, anisotropy plays significant role in dictating the direction of flow that becomes no longer dependent only on driving forces like the pressure gradient and gravity but also on the principal directions of anisotropy. Therefore, there has been a great deal of motivation to consider anisotropy into the subsurface flow and transport models. In this dissertation, we present subsurface flow modeling in single and dual continuum anisotropic porous media, which include the single-phase groundwater flow coupled with the solute transport in anisotropic porous media, the two-phase flow with gravity effect in anisotropic porous media, and the natural gas flow in anisotropic shale reservoirs. We have employed the multipoint flux approximation (MPFA) method to handle anisotropy in the flow model. The MPFA method is designed to provide correct discretization of the flow equations for general orientation of the principal directions of the permeability tensor. The implementation of MPFA method is combined with the experimenting pressure field approach, a newly developed technique that enables the solution of the global problem breaks down into the solution of multitude of local problems. The numerical results of the study demonstrate the significant effects of anisotropy of the subsurface formations. For the single-phase groundwater flow coupled with the solute transport modeling in anisotropic porous media, the results shows the strong impact of anisotropy on the pressure field and the migration of the solute concentration. For the two-phase flow modeling with gravity effect in anisotropic porous media, it is observed that the buoyancy-driven flow, which emerges due to the density differences between the

  8. Characterization of Microbial Communities in Subsurface Nuclear Blast Cavities of the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Duane; Russell, Chuck; Marshall, Matthew; Czerwinski, Ken; Daly, Michael J; Zavarin, Mavrik

    2008-02-08

    This exploratory research project is designed to test fundamental hypotheses concerning the possible existence and nature of indigenous microbial populations in Nevada Test Site (NTS) subsurface nuclear blast cavities. Although subsurface microbiological studies have been performed at the NTS in the past, radioactive zones have yet to be addressed. Nuclear blast zone microbiology is a completely new field and our team is well-positioned to collect and analyze samples that have never before been available to microbiologists. Relevant samples are now being obtained by incorporating microbiological collections into an ongoing annual hot well sampling program being conducted by other agencies. A combination of cultivation-based and molecular microbial detection protocols is being utilized at multiple locations to survey for uncultivable microorganisms and to develop a culture collection which will be characterized for radionuclide- and metal-reduction capabilities. Given that redox manipulations mediated by microorganisms can impact the mobility of DOE contaminants, a positive outcome from this work would have significant implications for management strategies at this and other DOE sites. A primary objective of the project has been the establishment of the regulatory and technical framework necessary to enable our acquisition of samples. Thus, much of our activity in the first phase of this work has involved the development an approved Field Area Work Plan (FAWP), Radiological Work Permit (RWP), and other documentation required for radiological work at the NTS. We have also invested significant time into ensuring that all personnel possess the required training (e.g. Radworker II and 40 hr. HAZWOPER) for access to the hot well sampling sites. Laboratory facilities, required for field processing of radioactive samples as well as DNA extraction and other manipulations, have been secured both the NTS (Mercury, NV) and UNLV. Although our year-1 field work was delayed due

  9. Microbial biomass and activity in subsurface sediments from Vejen, Denmark

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Winding, Anne

    1992-01-01

    Subsurface sediment samples were collected from 4 to 31 m below landsurface in glacio-fluvial sediments from the Quaternary period. The samples were described in terms of pH, electrical conductivity, chloride concentration, organic matter content, and grain size distribution. Viable counts......, AODC increased and the mineralization rate declined. Intrinsic permeability calculated from grain size correlated positively with mineralization rate for acetate. Statistical correlation analysis showed high correlations between some of the abiotic parameters, but it was not possible to point out...... a single abiotic parameter that could explain the variation of size and activity of the microbial population. The microbial data obtained in these geologically young sediments were compared to literature data from older sediments, and this comparison showed that age and type of geological formation might...

  10. Next Steps Forward in Understanding Martian Surface and Subsurface Chemistry

    Science.gov (United States)

    Carrier, Brandi L.

    2017-09-01

    The presence of oxidants such as hydrogen peroxide (H2O2) and perchlorate (ClO4-), which have been detected on Mars, has significant implications for chemistry and astrobiology. These oxidants can increase the reactivity of the Martian soil, accelerate the decomposition of organic molecules, and depress the freezing point of water. The study by Crandall et al. "Can Perchlorates be Transformed to Hydrogen Peroxide Products by Cosmic Rays on the Martian Surface" reveals a new formation mechanism by which hydrogen peroxide and other potential oxidants can be generated via irradiation of perchlorate by cosmic rays. This study represents an important next step in developing a full understanding of Martian surface and subsurface chemistry, particularly with respect to degradation of organic molecules and potential biosignatures.

  11. Feasibility and induced effects of subsurface porous media hydrogen storage

    Science.gov (United States)

    Tilmann Pfeiffer, Wolf; Li, Dedong; Wang, Bo; Bauer, Sebastian

    2015-04-01

    Fluctuations in energy production from renewable sources like wind or solar power can lead to shortages in energy supply which can be mitigated using energy storage concepts. Underground storage of hydrogen in porous sandstone formations could be a storage option for large amounts of energy over long storage cycles. However, this use of the subsurface requires an analysis of possible interactions with other uses of the subsurface such as geothermal energy storage or groundwater abstraction. This study aims at quantifying the feasibility of porous media hydrogen storage to provide stored energy on a timescale of several days to weeks as well as possible impacts on the subsurface. The hypothetical storage site is based on an anticlinal structure located in Schleswig-Holstein, northern Germany. The storage is injected and extracted using five wells completed in a partially eroded, heterogeneous sandstone layer in the top of the structure at a depth of about 500 m. The storage formation was parameterized based on a local facies model with intrinsic permeabilities of 250-2500 mD and porosities of 35-40%. Storage initialization and subsequent storage cycles, each consisting of a hydrogen injection and extraction, were numerically simulated. The simulation results indicate the general feasibility of this hydrogen storage concept. The simulated sandstone formation is able to provide an average of around 1480 t of hydrogen per week (1830 TJ) which is about 5% of the total weekly energy production or about 10% of the weekly energy consumption of Schleswig-Holstein with the hydrogen production rate being the limiting factor of the overall performance. Induced hydraulic effects are a result of the induced overpressure within the storage formation. Propagation of the pressure signal does not strongly depend on the formation heterogeneity and thus shows approximately radial characteristics with one bar pressure change in distances of about 5 km from the injection wells. Thermal

  12. Nanoscale subsurface- and material-specific identification of single nanoparticles.

    Science.gov (United States)

    Nuño, Zachary; Hessler, Brandon; Ochoa, Jerry; Shon, Young-Seok; Bonney, Codi; Abate, Yohannes

    2011-10-10

    We report on high resolution subsurface and material specific differentiation of silica, Au and silica-capped Au nanoparticles using scattering-type scanning near-field optical microscopy (s-SNOM) in the visible (λ=633 nm) and mid-infrared (λ=10.7 μm) frequencies. Strong optical contrast is observed in the visible wavelength, mainly because of the dipolar plasmon resonance of the embedded Au nanoparticles which is absent in the infrared. We show that the use of small tapping amplitude improves the apparent image contrast in nanoparticles by causing increased tip-particle and reduced tip-substrate interactions. Experimental results are in excellent agreement with extended dipole model calculations modified to include the capping layer characterized by its refractive index.

  13. Phase shift reflectometry for sub-surface defect detection

    Science.gov (United States)

    Asundi, Anand; Lei, Huang; Eden, Teoh Kang Min; Sreemathy, Parthasarathy; May, Watt Sook

    2012-11-01

    Phase Shift Reflectometry has recently been seen as a novel alternative to interferometry since it can provide warpage measurement over large areas with no need for large optical components. To confirm its capability and to explore the use of this method for sub-surface defect detection, a Chinese magic mirror is used. This bronze mirror which dates back to the Chinese Han Dynasty appears at first sight to be an ordinary convex mirror. However, unlike a normal mirror, when illuminated by a beam of light, an image is formed onto a screen. It has been hypothesized that there are indentations inside the mirror which alter the path of reflected light rays and hence the reflected image. This paper explores various methods to measure these indentations. Of the methods test Phase Shift Reflectometry (PSR) was found suitable to be the most suitable both in terms of the sensitivity and the field of view.

  14. Coupled modelling of stress and fluid flow, with applications to gas extraction and disposal of energy residues

    NARCIS (Netherlands)

    Orlic, B.

    2003-01-01

    Coupled flow-stress numerical models have been increasingly used in geomechanical studies for a better understanding and more accurate prediction of subsurface behaviour due to the extraction of hydrocarbons and geological storage of energy residues. Two application studies are described

  15. Subsurface deformation and the role of surface texture—A study with ...

    Indian Academy of Sciences (India)

    The extent of subsurface deformation below the worn surface influences friction and transfer layer formation during sliding. Thus, in this study, the extent of plastic deformation and strain localization events that occur at various depths beneath the worn surface in the subsurface zones of Cu pins slid against steel plate with ...

  16. Subsurface temperature of the onshore Netherlands: new temperature dataset and modelling

    NARCIS (Netherlands)

    Bonté, D.; Wees, J.-D. van; Verweij, J.M.

    2012-01-01

    Subsurface temperature is a key parameter for geothermal energy prospection in sedimentary basins. Here, we present the results of a 3D temperature modelling using a thermal-tectonic forward modelling method, calibrated with subsurface temperature measurements in the Netherlands. The first step

  17. Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture

    Science.gov (United States)

    West, Phillip B [Idaho Falls, ID; Novascone, Stephen R [Idaho Falls, ID; Wright, Jerry P [Idaho Falls, ID

    2011-09-27

    Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture are described. According to one embodiment, an earth analysis method includes engaging a device with the earth, analyzing the earth in a single substantially lineal direction using the device during the engaging, and providing information regarding a subsurface feature of the earth using the analysis.

  18. 3D modelling of the shallow subsurface of Zeeland, the Netherlands

    NARCIS (Netherlands)

    Stafleu, J.; Busschers, F.S.; Maljers, D.; Menkovic, A.

    2011-01-01

    The Geological Survey of the Netherlands aims at building a 3D geological voxel model of the upper 30 m of the subsurface of the Netherlands in order to provide a sound basis for subsurface related questions on, amongst others, groundwater extraction and management, land subsidence studies,

  19. Subsurface drainage to enable the cultivation of winter crops in consolidated paddy fields in Northern Iran

    NARCIS (Netherlands)

    Jafari-Talukolaee, Mehdi; Ritzema, Henk; Darzi-Naftchali, Abdullah; Shahnazari, Ali

    2016-01-01

    Subsurface drainage is a prerequisite to grow winter crops in the consolidated paddy fields in Northern Iran. A four-year study (2011-2015) was conducted to quantify the effects of subsurface drainage on the saturated hydraulic conductivity, water table, drain discharge and winter crop yields.

  20. A Unified 3D Spatial Data Model for Surface and Subsurface Spatial ...

    African Journals Online (AJOL)

    Knowledge about the surface and subsurface 3D objects for city centres, mining and 3D cadastre will create awareness among stakeholders for effective planning of a city or mine. This paper provides a discussion for 3D surface and subsurface integration. Various 3D spatial data models currently in existence for the ...

  1. Influence of Rock Mineralogy on Subsurface Water in Ado-Ekiti ...

    African Journals Online (AJOL)

    Sudden geometric increase in population of Ado-Ekiti has lead to an increase in demand for water and harnessing of subsurface water reserve. This research investigated the possible infiltration of dissolved mineral from weathered rock into subsurface water in the area (basement complex rocks), and comparing the ...

  2. Influence of Rock Mineralogy on Subsurface Water in Ado-Ekiti ...

    African Journals Online (AJOL)

    Nekky Umera

    Abstract. Sudden geometric increase in population of Ado-Ekiti has lead to an increase in demand for water and harnessing of subsurface water reserve. This research investigated the possible infiltration of dissolved mineral from weathered rock into subsurface water in the area (basement complex rocks), and comparing ...

  3. Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture

    Science.gov (United States)

    West, Phillip B [Idaho Falls, ID; Novascone, Stephen R [Idaho Falls, ID; Wright, Jerry P [Idaho Falls, ID

    2012-05-29

    Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture are described. According to one embodiment, an earth analysis method includes engaging a device with the earth, analyzing the earth in a single substantially lineal direction using the device during the engaging, and providing information regarding a subsurface feature of the earth using the analysis.

  4. Time-Lapse Electrical Resistivity Investigations for Imaging the Grouting Injection in Shallow Subsurface Cavities

    Directory of Open Access Journals (Sweden)

    Muhammad Farooq

    2014-01-01

    Full Text Available The highway of Yongweol-ri, Muan-gun, south-western part of the South Korean Peninsula, is underlain by the abandoned of subsurface cavities, which were discovered in 2005. These cavities lie at shallow depths with the range of 5∼15 meters below the ground surface. Numerous subsidence events have repeatedly occurred in the past few years, damaging infrastructure and highway. As a result of continuing subsidence issues, the Korean Institute of Geosciences and Mineral Resources (KIGAM was requested by local administration to resolve the issue. The KIGAM used geophysical methods to delineate subsurface cavities and improve more refined understanding of the cavities network in the study area. Cement based grouting has been widely employed in the construction industry to reinforce subsurface ground. In this research work, time-lapse electrical resistivity surveys were accomplished to monitor the grouting injection in the subsurface cavities beneath the highway, which have provided a quasi-real-time monitoring for modifying the subsurface cavities related to ground reinforcement, which would be difficult with direct methods. The results obtained from time-lapse electrical resistivity technique have satisfactory imaged the grouting injection experiment in the subsurface cavities beneath the highway. Furthermore, the borehole camera confirmed the presence of grouting material in the subsurface cavities, and hence this procedure increases the mechanical resistance of subsurface cavities below the highway.

  5. Subsurface deformation and the role of surface texture—A study with ...

    Indian Academy of Sciences (India)

    Abstract. The extent of subsurface deformation below the worn surface influences friction and transfer layer formation during sliding. Thus, in this study, the extent of plastic deformation and strain localization events that occur at various depths beneath the worn surface in the subsurface zones of Cu pins slid against steel ...

  6. Molecular Simulation towards Efficient and Representative Subsurface Reservoirs Modeling

    KAUST Repository

    Kadoura, Ahmad

    2016-09-01

    This dissertation focuses on the application of Monte Carlo (MC) molecular simulation and Molecular Dynamics (MD) in modeling thermodynamics and flow of subsurface reservoir fluids. At first, MC molecular simulation is proposed as a promising method to replace correlations and equations of state in subsurface flow simulators. In order to accelerate MC simulations, a set of early rejection schemes (conservative, hybrid, and non-conservative) in addition to extrapolation methods through reweighting and reconstruction of pre-generated MC Markov chains were developed. Furthermore, an extensive study was conducted to investigate sorption and transport processes of methane, carbon dioxide, water, and their mixtures in the inorganic part of shale using both MC and MD simulations. These simulations covered a wide range of thermodynamic conditions, pore sizes, and fluid compositions shedding light on several interesting findings. For example, the possibility to have more carbon dioxide adsorbed with more preadsorbed water concentrations at relatively large basal spaces. The dissertation is divided into four chapters. The first chapter corresponds to the introductory part where a brief background about molecular simulation and motivations are given. The second chapter is devoted to discuss the theoretical aspects and methodology of the proposed MC speeding up techniques in addition to the corresponding results leading to the successful multi-scale simulation of the compressible single-phase flow scenario. In chapter 3, the results regarding our extensive study on shale gas at laboratory conditions are reported. At the fourth and last chapter, we end the dissertation with few concluding remarks highlighting the key findings and summarizing the future directions.

  7. Shallow Subsurface transport and eruption of basaltic foam

    Science.gov (United States)

    Parcheta, C. E.; Mitchell, K. L.

    2016-12-01

    Volcanic fissure vents are difficult to quantify, and details of eruptive behavior are elusive even though it is the most common eruption mechanism on Earth and across the solar system. A fissure's surface expression is typically concealed, but when a fissure remains exposed, its subsurface conduit can be mapped post-eruptively with VolcanoBot. The robot uses a NIR structured light sensor that reproduces a 3D surface model to cm-scale accuracy, documenting the shallow conduit. VolcanoBot3 has probed >1000m3 of volcanic fissure vents at the Mauna Ulu fissure system on Kilauea. Here we present the new 3D model of a flared vent on the Mauna Ulu fissure system. We see a self-similar pattern of irregularities on the fissure walls throughout the entire shallow subsurface, implying a fracture mechanical origin similar to faults. These irregularities are typically 1 m across, protrude 30 cm horizontally into the drained fissure, and have a vertical spacing of 2-3 m. However, irregularity size is variable and distinct with depth, potentially reflecting stratigraphy in the wall rock. Where piercing points are present, we infer the dike broke the wall rock in order to propagate upwards; where they are not, we infer that syn-eruptive mechanical erosion has taken place. One mechanism for mechanical erosion is supersonic shocks, which may occur in Hawaiian fountains. We are calculating the speed of sound in 64% basaltic foam, which appears to be the same velocity (or slightly slower) than inferred eruption velocities. Irregularities are larger than the maximum 10% wall roughness used in engineering fluid dynamic studies, indicating that magma fluid dynamics during fissure eruptions are probably not as passive nor as simple as previously thought. We are currently using the mapped conduit geometries and derived speed of sound for basaltic foam in fluid dynamical modeling of fissure-fed lava fountains.

  8. High-resolution subsurface water-ice distributions on Mars.

    Science.gov (United States)

    Bandfield, Joshua L

    2007-05-03

    Theoretical models indicate that water ice is stable in the shallow subsurface (depths of Mars at high latitudes. These models have been mainly supported by the observed presence of large concentrations of hydrogen detected by the Gamma Ray Spectrometer suite of instruments on the Mars Odyssey spacecraft. The models and measurements are consistent with a water-ice table that steadily increases in depth with decreasing latitude. More detailed modelling has predicted that the depth at which water ice is stable can be highly variable, owing to local surface heterogeneities such as rocks and slopes, and the thermal inertia of the ground cover. Measurements have, however, been limited to the footprint (several hundred kilometres) of the Gamma Ray Spectrometer suite, preventing the observations from documenting more detailed water-ice distributions. Here I show that by observing the seasonal temperature response of the martian surface with the Thermal Emission Imaging System on the Mars Odyssey spacecraft, it is possible to observe such heterogeneities at subkilometre scale. These observations show significant regional and local water-ice depth variability, and, in some cases, support distributions in the subsurface predicted by atmospheric exchange and vapour diffusion models. The presence of water ice where it follows the depth of stability under current climatic conditions implies an active martian water cycle that responds to orbit-driven climate cycles. Several regions also have apparent deviations from the theoretical stability level, indicating that additional factors influence the ice-table depth. The high-resolution measurements show that the depth to the water-ice table is highly variable within the potential Phoenix spacecraft landing ellipses, and is likely to be variable at scales that may be sampled by the spacecraft.

  9. Image of a subsurface current core in the southern South China Sea

    Directory of Open Access Journals (Sweden)

    Q. S. Tang

    2013-07-01

    Full Text Available A legacy seismic transect acquired on 30 and 31 May 2009 in the southern South China Sea (SCS was reprocessed to reveal the thermohaline structure of the water column. In the study region, a mesoscale subsurface lens with extraordinary features was detected at 113.5° E, 11.5° N. It is centred at 450 m depth, occupies both the subsurface and intermediate water from 250 to 600 m, and has an intersection diameter of around 60 km. The simulated results from Hybrid Coordinate Ocean Model reveal an eddy-induced subsurface current running southwestward along the deep basin edge and suggest that the imaged lens is a snapshot of the subsurface current core rather than a subsurface eddy.

  10. Active infrared thermography for visualizing subsurface micro voids in an epoxy molding compound

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ji Yeol [Test and Package Center, Samsung Electronics, Asan(Korea, Republic of); Hwang, Soon Kyu; Choi, Jae Mook; Sohn, Hoon [Dept. of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2017-04-15

    This paper presents an automated subsurface micro void detection technique based on pulsed infrared thermography for inspecting epoxy molding compounds (EMC) used in electronic device packaging. Subsurface micro voids are first detected and visualized by extracting a lock-in amplitude image from raw thermal images. Binary imaging follows to achieve better visualization of subsurface micro voids. A median filter is then applied for removing sparse noise components. The performance of the proposed technique is tested using 36 EMC samples, which have subsurface (below 150 μm ~ 300 μm from the inspection surface) micro voids (150 μm ~ 300 μm in diameter). The experimental results show that the subsurface micro voids can be successfully detected without causing any damage to the EMC samples, making it suitable for automated online inspection.

  11. Natural and enhanced anaerobic degradation of 1,1,1-trichloroethane and its degradation products in the subsurface – A critical review

    DEFF Research Database (Denmark)

    Scheutz, Charlotte; Durant, Neal D.; Hansen, Maria Heisterberg

    2011-01-01

    demonstrating the utility of bioaugmentation with Dhb cultures for remediation of TCA in the field. In this paper we review the state-of-the-science of TCA degradation in aquifers, examining results from both laboratory experiments and twenty-two field case studies, focusing on the capabilities and limits...

  12. Electromagnetic clutches and couplings

    CERN Document Server

    Vorob'Yeva, T M; Fry, D W; Higinbotham, W

    2013-01-01

    Electromagnetic Clutches and Couplings contains a detailed description of U.S.S.R. electromagnetic friction clutches, magnetic couplings, and magnetic particle couplings. This book is divided into four chapters. The first chapter discusses the design and construction of magnetic (solenoid-operated) couplings, which are very quick-acting devices and used in low power high-speed servo-systems. Chapter 2 describes the possible fields of application, design, construction, and utilization of magnetic particle couplings. The aspects of construction, design, and utilization of induction clutches (sli

  13. Planetary science and exploration in the deep subsurface: results from the MINAR Program, Boulby Mine, UK

    Science.gov (United States)

    Payler, Samuel J.; Biddle, Jennifer F.; Coates, Andrew J.; Cousins, Claire R.; Cross, Rachel E.; Cullen, David C.; Downs, Michael T.; Direito, Susana O. L.; Edwards, Thomas; Gray, Amber L.; Genis, Jac; Gunn, Matthew; Hansford, Graeme M.; Harkness, Patrick; Holt, John; Josset, Jean-Luc; Li, Xuan; Lees, David S.; Lim, Darlene S. S.; McHugh, Melissa; McLuckie, David; Meehan, Emma; Paling, Sean M.; Souchon, Audrey; Yeoman, Louise; Cockell, Charles S.

    2017-04-01

    The subsurface exploration of other planetary bodies can be used to unravel their geological history and assess their habitability. On Mars in particular, present-day habitable conditions may be restricted to the subsurface. Using a deep subsurface mine, we carried out a program of extraterrestrial analog research - MINe Analog Research (MINAR). MINAR aims to carry out the scientific study of the deep subsurface and test instrumentation designed for planetary surface exploration by investigating deep subsurface geology, whilst establishing the potential this technology has to be transferred into the mining industry. An integrated multi-instrument suite was used to investigate samples of representative evaporite minerals from a subsurface Permian evaporite sequence, in particular to assess mineral and elemental variations which provide small-scale regions of enhanced habitability. The instruments used were the Panoramic Camera emulator, Close-Up Imager, Raman spectrometer, Small Planetary Linear Impulse Tool, Ultrasonic drill and handheld X-ray diffraction (XRD). We present science results from the analog research and show that these instruments can be used to investigate in situ the geological context and mineralogical variations of a deep subsurface environment, and thus habitability, from millimetre to metre scales. We also show that these instruments are complementary. For example, the identification of primary evaporite minerals such as NaCl and KCl, which are difficult to detect by portable Raman spectrometers, can be accomplished with XRD. By contrast, Raman is highly effective at locating and detecting mineral inclusions in primary evaporite minerals. MINAR demonstrates the effective use of a deep subsurface environment for planetary instrument development, understanding the habitability of extreme deep subsurface environments on Earth and other planetary bodies, and advancing the use of space technology in economic mining.

  14. The thermal impact of subsurface building structures on urban groundwater resources - A paradigmatic example.

    Science.gov (United States)

    Epting, Jannis; Scheidler, Stefan; Affolter, Annette; Borer, Paul; Mueller, Matthias H; Egli, Lukas; García-Gil, Alejandro; Huggenberger, Peter

    2017-10-15

    Shallow subsurface thermal regimes in urban areas are increasingly impacted by anthropogenic activities, which include infrastructure development like underground traffic lines as well as industrial and residential subsurface buildings. In combination with the progressive use of shallow geothermal energy systems, this results in the so-called subsurface urban heat island effect. This article emphasizes the importance of considering the thermal impact of subsurface structures, which commonly is underestimated due to missing information and of reliable subsurface temperature data. Based on synthetic heat-transport models different settings of the urban environment were investigated, including: (1) hydraulic gradients and conductivities, which result in different groundwater flow velocities; (2) aquifer properties like groundwater thickness to aquitard and depth to water table; and (3) constructional features, such as building depths and thermal properties of building structures. Our results demonstrate that with rising groundwater flow velocities, the heat-load from building structures increase, whereas down-gradient groundwater temperatures decrease. Thermal impacts on subsurface resources therefore have to be related to the permeability of aquifers and hydraulic boundary conditions. In regard to the urban settings of Basel, Switzerland, flow velocities of around 1 md-1 delineate a marker where either down-gradient temperature deviations or heat-loads into the subsurface are more relevant. Furthermore, no direct thermal influence on groundwater resources should be expected for aquifers with groundwater thicknesses larger 10m and when the distance of the building structure to the groundwater table is higher than around 10m. We demonstrate that measuring temperature changes down-gradient of subsurface structures is insufficient overall to assess thermal impacts, particularly in urban areas. Moreover, in areas which are densely urbanized, and where groundwater flow

  15. Geomorphic factors related to the persistence of subsurface oil from the Exxon Valdez oil spill

    Science.gov (United States)

    Nixon, Zachary; Michel, Jacqueline; Hayes, Miles O.; Irvine, Gail V.; Short, Jeffrey

    2013-01-01

    Oil from the 1989 Exxon Valdez oil spill has persisted along shorelines of Prince William Sound, Alaska, for more than two decades as both surface and subsurface oil residues. To better understand the distribution of persistent subsurface oil and assess the potential need for further restoration, a thorough and quantitative understanding of the geomorphic factors controlling the presence or absence of subsurface oil is required. Data on oiling and geomorphic features were collected at 198 sites in Prince William Sound to identify and quantify the relationships among these geomorphic factors and the presence and absence of persistent subsurface oil. Geomorphic factors associated with the presence of subsurface oil were initial oil exposure, substrate permeability, topographic slope, low exposure to waves, armoring on gravel beaches, tombolos, natural breakwaters, and rubble accumulations. Geomorphic factors associated with the absence of subsurface oil were impermeable bedrock; platforms with thin sediment veneer; fine-grained, well-sorted gravel beaches with no armor; and low-permeability, raised bay-bottom beaches. Relationships were found between the geomorphic and physical site characteristics and the likelihood of encountering persistent subsurface oiling at those sites. There is quantitative evidence of more complex interactions between the overall wave energy incident at a site and the presence of fine-scale geomorphic features that may have provided smaller, local wave energy sheltering of oil. Similarly, these data provide evidence for interactions between the shoreline slope and the presence of angular rubble, with decreased likelihood for encountering subsurface oil at steeply sloped sites except at high-angle sheltered rubble shoreline locations. These results reinforce the idea that the interactions of beach permeability, stability, and site-specific wave exposure are key drivers for subsurface oil persistence in exposed and intermittently exposed mixed

  16. Retrieval of Ocean Subsurface Particulate Backscattering Coefficient from Space-Borne CALIOP Lidar Measurement

    Science.gov (United States)

    Lu, Xiaomei; Hu, Yongxiang; Pelon, Jacques; Trepte, Chip; Liu, Katie; Rodier, Sharon; Zeng, Shan; Luckher, Patricia; Verhappen, Ron; Wilson, Jamie; hide

    2016-01-01

    A new approach has been proposed to determine ocean subsurface particulate backscattering coefficient bbp from CALIOP 30deg off-nadir lidar measurements. The new method also provides estimates of the particle volume scattering function at the 180deg scattering angle. The CALIOP based layer-integrated lidar backscatter and particulate backscattering coefficients are compared with the results obtained from MODIS ocean color measurements. The comparison analysis shows that ocean subsurface lidar backscatter and particulate backscattering coefficient bbp can be accurately obtained from CALIOP lidar measurements, thereby supporting the use of space-borne lidar measurements for ocean subsurface studies.

  17. Imaging of the Hydrogen Subsurface Site in Rutile TiO2

    DEFF Research Database (Denmark)

    Enevoldsen, Georg Herborg; Pinto, Henry; Foster, Adam S

    2009-01-01

    From an interplay between simultaneously recorded noncontact atomic force microscopy and scanning tunneling microscopy images and simulations based on density functional theory, we reveal the location of single hydrogen species in the surface and subsurface layers of rutile TiO2. Subsurface...... hydrogen atoms (H-sub) are found to reside in a stable interstitial site as subsurface OH groups detectable in scanning tunneling microscopy as a characteristic electronic state but imperceptible to atomic force microscopy. The combined atomic force microscopy, scanning tunneling microscopy, and density...... functional theory study demonstrates a general scheme to reveal near surface defects and interstitials in poorly conducting materials....

  18. Molten salt as a heat transfer fluid for heating a subsurface formation

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Scott Vinh (Houston, TX); Vinegar, Harold J. (Bellaire, TX)

    2010-11-16

    A heating system for a subsurface formation includes a conduit located in an opening in the subsurface formation. An insulated conductor is located in the conduit. A material is in the conduit between a portion of the insulated conductor and a portion of the conduit. The material may be a salt. The material is a fluid at operating temperature of the heating system. Heat transfers from the insulated conductor to the fluid, from the fluid to the conduit, and from the conduit to the subsurface formation.

  19. Retrieval of ocean subsurface particulate backscattering coefficient from space-borne CALIOP lidar measurements.

    Science.gov (United States)

    Lu, Xiaomei; Hu, Yongxiang; Pelon, Jacques; Trepte, Charles; Liu, Katie; Rodier, Sharon; Zeng, Shan; Lucker, Patricia; Verhappen, Ron; Wilson, Jamie; Audouy, Claude; Ferrier, Christophe; Haouchine, Said; Hunt, Bill; Getzewich, Brian

    2016-12-12

    A new approach has been proposed to determine ocean subsurface particulate backscattering coefficient bbp from CALIOP 30° off-nadir lidar measurements. The new method also provides estimates of the particle volume scattering function at the 180° scattering angle. The CALIOP based layer-integrated lidar backscatter and particulate backscattering coefficients are compared with the results obtained from MODIS ocean color measurements. The comparison analysis shows that ocean subsurface lidar backscatter and particulate backscattering coefficient bbp can be accurately obtained from CALIOP lidar measurements, thereby supporting the use of space-borne lidar measurements for ocean subsurface studies.

  20. Exploratory data analysis on data generated in the DOE subsurface microbiology program

    Energy Technology Data Exchange (ETDEWEB)

    Meglen, R.R.

    1990-06-01

    The preliminary results from the innovative subsurface microbiology research program indicate that new data on the nature of the link between the geosphere and biosphere have been generated. The diversity of scientific disciplines represented in the subsurface microbiology program reflects the complexity of the system under study. The research carried out by national laboratory and university research scientists is addressing fundamental questions about the abundance of microorganisms and factors controlling microbial activity in the complex subsurface hydrologic and geochemical environment. Long-term implications of this research for mitigating contamination are clear and researchers share the broader objective of linking the basic science with applied work.

  1. Dynamics of Bacterial Community Abundance and Structure in Horizontal Subsurface Flow Wetland Mesocosms Treating Municipal Wastewater

    Directory of Open Access Journals (Sweden)

    Kristjan Oopkaup

    2016-10-01

    Full Text Available Dynamics of bacterial community abundance and structure of a newly established horizontal subsurface flow (HSSF pilot-scale wetland were studied using high-throughput sequencing and quantitative polymerase chain reaction (PCR methods. Bacterial community abundance increased rapidly within one month and stabilised thereafter in three replicate HSSF constructed wetland (CW mesocosms. The most dominant phylum was Proteobacteria, followed by Bacteroidetes in wetland media biofilms and Firmicutes in influent wastewater. CW bacterial community diversity increased over time and was positively related to the wastewater treatment efficiency. Increase in the abundance of total bacteria in the community was accompanied with the abundance of denitrifying bacteria that promoted nitrate and nitrite removal from the wastewater. During the 150-day study period, similar patterns of bacterial community successions were observed in replicate HSSF CW mesocosms. The data indicate that successions in the bacterial community in HSSF CW are shaped by biotic interactions, with a significant contribution made by external abiotic factors such as influent chemical parameters. Network analysis of the bacterial community revealed that organic matter and nitrogen removal in HSSF CW could be, in large part, allocated to a small subset of tightly interconnected bacterial species. The diversity of bacterial community and abundance of denitrifiers were good predictors of the removal efficiency of ammonia, nitrate and total organic C in HSSF CW mesocosms, while the removal of the seven-day biochemical oxygen demand (BOD7 was best predicted by the abundance of a small set of bacterial phylotypes. The results suggest that nitrogen removal in HSSF CW consist of two main pathways. The first is heterotrophic nitrification, which is coupled with aerobic denitrification and mediated by mixotrophic nitrite-oxidizers. The second pathway is anaerobic denitrification, which leads to gaseous

  2. Optimal conditions for chlorothalonil and dissolved organic carbon in horizontal subsurface flow constructed wetlands.

    Science.gov (United States)

    Rìos-Montes, Karina A; Casas-Zapata, Juan C; Briones-Gallardo, Roberto; Peñuela, Gustavo

    2017-04-03

    The most efficient system of horizontal subsurface flow constructed wetlands (HSSFCW) for removing dissolved organic carbon (DOC) in the presence of chlorothalonil pesticide (CLT) present in synthetic domestic wastewater was determined using the macrophyte Phragmites australis. Two concentrations of CLT (85 and 385 μg L-1) and one concentration of glucose (20 mg L-1) were evaluated in four pilot scale horizontal surface flow constructed wetlands coupled with two sizes of silica gravel, igneous gravel, fine chalky gravel (3.18-6.35 mm), coarse gravel (12.70-25.40 mm) and two water surface heights (20 and 40 cm). For a month, wetlands were acclimated with domestic wastewater. Some groups of bacteria were also identified in the biofilm attached to the gravel. In each treatment periodic samplings were conducted in the influent and effluent. Chlorothalonil was quantified by gas chromatography (GC-ECD m), DOC by an organic carbon analyzer and bacterial groups using conventional microbiology in accordance with Standard Methods. The largest removals of DOC (85.82%-85.31%) were found when using fine gravel (3.18-6.35 mm) and the lower layer of water (20 cm). The bacterial groups quantified in the biofilm were total heterotrophic, revivable heterotrophic, Pseudomonas and total coliforms. The results of this study indicate that fine grain gravel (3.18-6.35 mm) and both water levels (20 to 40 cm) can be used in the removal of organic matter and for the treatment of agricultural effluents contaminated with organo-chloride pesticides like CLT in HSSFCW.

  3. Subsurface Treatment of Domestic Wastewater Using Single Domicile Constructed Wetlands

    Science.gov (United States)

    Aseltyne, T.; Steer, D.; Fraser, L.

    2001-05-01

    Analysis of one year of input versus output water quality monitoring data from nine household wastewater treatment wetlands in western Ohio indicates that these systems substantially reduce effluent loads delivered to the local watershed. Overall performance as measured by output water quality improvement varies widely between the nine systems despite their close proximity and identical design. These three-cell systems (septic tank with 2 subsurface wetland cells) are found to reduce biological oxygen demand (BOD) 70-98%, fecal coliform 60-99.9%, NH3 29-97%, Phosphorus 21-99.9% and total suspended solids (TSS) up to 97%. NO3/NO2 readings were only taken at the second wetland cell, but show that NO3/NO2 levels are at 0.005-5.01 mg/l and well below the USEPA standards for discharge from a wetland. On average, the pH of the wastewater increases from 6.6 at the septic tank to 8.7 at the wetland output. Nearly all the monitoring data indicate clear decreases in nutrient loads and bacteria though individual systems are found to non-systematically fail to meet EPA discharge guidelines for one or more of the monitored loads. Preliminary analysis of the data indicates a decrease in overall efficiency of the wetlands in April that may be related to seasonal factors. These systems will be monitored for the next three years in order to relate changing performance trends to seasonal variability.

  4. Evidence for subsurface water ice in Korolev crater, Mars

    Science.gov (United States)

    Armstrong, J.C.; Titus, T.N.; Kieffer, H.H.

    2005-01-01

    Following the work of Kieffer and Titus (2001, Icarus 154, 162-180), we present results of thermal IR observations of Korolev crater, located at ???73?? latitude in the martian northern polar region. Similar to techniques employed by Titus et al. (2003, Science 299, 1048-1050), we use infrared images from the Thermal Emission Imaging System (THEMIS) aboard Mars Odyssey to identify several regions within the crater basin with distinct thermal properties that correlate with topography. The THEMIS results show these regions exhibit temperature variations, spatially within the crater and throughout the martian year. In addition to the variations identified in the THEMIS observations, Mars Global Surveyor Thermal Emission Spectrometer (TES) observations show differences in albedo and temperature of these regions on both daily and seasonal cycles. Modeling annual temperature variations of the surface, we use TES observations to examine the thermal properties of these regions. This analysis reveals the crater interior deposits are likely thick layers (several meters) of high thermal inertia material (water ice, or extremely ice-rich regolith). Spatial variations of the physical properties of these regions are likely due to topography and possibly variations in the subsurface material itself. The nature of these deposits may help constrain polar processes, as well as provide context for the polar lander mission, Phoenix. ?? 2004 Elsevier Inc. All rights reserved.

  5. Influence of intraocular lens subsurface nanoglistenings on functional visual acuity.

    Directory of Open Access Journals (Sweden)

    Takahiro Hiraoka

    Full Text Available To investigate the influence of intraocular lens subsurface nanoglistenings (SSNGs on functional visual acuity (FVA, thirty-nine eyes of 29 patients were examined in this study. The SSNG group comprised 19 eyes of 14 patients (75.7± 5.4 years, mean ± standard deviation, and the control group comprised 20 eyes of 15 patients (73.6 ± 6.5 years. The SSNGs were diagnosed on the basis of the typical whitish IOL appearance upon slit-lamp examination and results of densitometry regarding surface light scattering using Scheimpflug images. The FVA measurement system (AS-28; Kowa, Aichi, Japan was used to examine changes in continuous visual acuity (VA over time, and visual function parameters such as FVA, visual maintenance ratio (VMR, maximum VA, minimum VA, standard deviation of VA, and number of blinks were assessed. The results were compared between the SSNG and control groups, and correlations of FVA parameters with the intensity of surface light scattering, time after surgery, and age were also evaluated. There were significant differences in VMR (P = 0.035 and standard deviation of VAs (P = 0.031 between the two groups, although no significant differences were found in baseline VA, FVA, maximum VA, minimum VA, and number of blinks. None of the FVA parameters showed any significant correlations with the intensity of surface light scattering, time after surgery, or age. There is a possibility that VA is unstable during a continuous gazing task in patients with SSNGs.

  6. Sub-Surface Windscreen for the Measurement of Outdoor Infrasound

    Science.gov (United States)

    Shams, Qamar A.; Burkett, Cecil G., Jr.; Comeaux, Toby; Zuckerwar, Allan J.; Weistroffer, George R.

    2008-01-01

    A windscreen has been developed that features two advantages favorable for the measurement of outdoor infrasound. First, the sub-surface location, with the top of the windscreen flush with the ground surface, minimizes the mean velocity of the impinging wind. Secondly, the windscreen material (closed cell polyurethane foam) has a sufficiently low acoustic impedance (222 times that of air) and wall thickness (0.0127 m) to provide a transmission coefficient of nearly unity over the infrasonic frequency range (0-20 Hz). The windscreen, a tightly-sealed box having internal dimensions of 0.3048 x 0.3048 x 0.3556 m, contains a microphone, preamplifier, and a cable feed thru to an external power supply. Provisions are made for rain drainage and seismic isolation. A three-element array, configured as an equilateral triangle with 30.48 m spacing and operating continuously in the field, periodically receives highly coherent signals attributed to emissions from atmospheric turbulence. The time delays between infrasonic signals received at the microphones permit determination of the bearing and elevation of the sources, which correlate well with locations of pilot reports (PIREPS) within a 320 km radius about the array. The test results are interpreted to yield spectral information on infrasonic emissions from clear air turbulence.

  7. “Altiarchaeales”: Uncultivated Archaea from the Subsurface

    Directory of Open Access Journals (Sweden)

    Alexander J. Probst

    2015-05-01

    Full Text Available Due to the limited cultivability of the vast majority of microorganisms, researchers have applied environmental genomics and other state-of-the-art technologies to gain insights into the biology of uncultivated Archaea and bacteria in their natural biotope. In this review, we summarize the scientific findings on a recently proposed order-level lineage of uncultivated Archaea called Altiarchaeales, which includes “Candidatus Altiarchaeum hamiconexum” as the most well-described representative. Ca. A. hamiconexum possesses a complex biology: thriving strictly anaerobically, this microorganism is capable of forming highly-pure biofilms, connecting the cells by extraordinary cell surface appendages (the “hami” and has other highly unusual traits, such as a double-membrane-based cell wall. Indicated by genomic information from different biotopes, the Altiarchaeales seem to proliferate in deep, anoxic groundwater of Earth’s crust bearing a potentially very important function: carbon fixation. Although their net carbon fixation rate has not yet been determined, they appear as highly abundant organisms in their biotopes and may thus represent an important primary producer in the subsurface. In sum, the research over more than a decade on Ca. A. hamiconexum has revealed many interesting features of its lifestyle, its genomic information, metabolism and ultrastructure, making this archaeon one of the best-studied uncultivated Archaea in the literature.

  8. STOMP Subsurface Transport Over Multiple Phases: User`s guide

    Energy Technology Data Exchange (ETDEWEB)

    White, M.D.; Oostrom, M.

    1997-10-01

    The U.S. Department of Energy, through the Office of Technology Development, has requested the demonstration of remediation technologies for the cleanup of volatile organic compounds and associated radionuclides within the soil and groundwater at arid sites. This demonstration program, called the VOC-Arid Soils Integrated Demonstration Program (Arid-ID), has been initially directed at a volume of unsaturated and saturated soil contaminated with carbon tetrachloride, on the Hanford Site near Richland, Washington. A principal subtask of the Arid-ID program involves the development of an integrated engineering simulator for evaluating the effectiveness and efficiency of various remediation technologies. The engineering simulator`s intended users include scientists and engineers who are investigating soil physics phenomena associated with remediation technologies. Principal design goals for the engineer simulator include broad applicability, verified algorithms, quality assurance controls, and validated simulations against laboratory and field-scale experiments. An important goal for the simulator development subtask involves the ability to scale laboratory and field-scale experiments to full-scale remediation technologies, and to transfer acquired technology to other arid sites. The STOMP (Subsurface Transport Over Multiple Phases) simulator has been developed by the Pacific Northwest National Laboratory for modeling remediation technologies. Information on the use, application, and theoretical basis of the STOMP simulator theory and discussions on the governing equations, constitutive relations, and numerical solution algorithms for the STOMP simulator.

  9. STOMP Subsurface Transport Over Multiple Phases: Application guide

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, W.E.; Aimo, N.J.; Oostrom, M.; White, M.D.

    1997-09-01

    The U.S. Department of Energy (DOE), through the Office of Technology Development, has requested the demonstration of remediation technologies for the cleanup of volatile organic compounds and associated radionuclides within the soil and ground water at arid sites. This demonstration program, called the VOC-Arid Soils Integrated Demonstrated Program (Arid-ID), has been initially directed at a volume of unsaturated and saturated soil contaminated with carbon tetrachloride on the Hanford Site near Richland, Washington. A principal subtask of the Arid-ID program involves the development of an integrated engineering simulator for evaluating the effectiveness and efficiency of various remediation technologies. The engineering simulator`s intended users include scientists and engineers who are investigating soil physics phenomena associated with remediation technologies. Principal design goals for the engineering simulator include broad applicability, verified algorithms, quality assurance controls, and validated simulations against laboratory and field-scale experiments. An important goal for the simulator development subtask involves the ability to scale laboratory and field-scale experiments to full-scale remediation technologies, and to transfer acquired technology to other arid sites. The STOMP (Subsurface Transport Over Multiple Phases) simulator has been developed by the Pacific Northwest Laboratory for modeling remediation technologies. Information on the use, application, and theoretical basis of the STOMP simulator are documented in three companion guide guides. This document, the Application Guide, provides a suite of example applications of the STOMP simulator.

  10. Nuclear magnetic resonance imaging of water content in the subsurface

    Energy Technology Data Exchange (ETDEWEB)

    J. Hendricks; T. Yao; A. Kearns

    1999-01-21

    Previous theoretical and experimental studies indicated that surface nuclear magnetic resonance (NMR) has the potential to provide cost-effective water content measurements in the subsurface and is a technology ripe for exploitation in practice. The objectives of this investigation are (a) to test the technique under a wide range of hydrogeological conditions and (b) to generalize existing NMR theories in order to correctly model NMR response from conductive ground and to assess properties of the inverse problem. Twenty-four sites with different hydrogeologic settings were selected in New Mexico and Colorado for testing. The greatest limitation of surface NMR technology appears to be the lack of understanding in which manner the NMR signal is influenced by soil-water factors such as pore size distribution, surface-to-volume ratio, paramagnetic ions dissolved in the ground water, and the presence of ferromagnetic minerals. Although the theoretical basis is found to be sound, several advances need to be made to make surface NMR a viable technology for hydrological investigations. There is a research need to investigate, under controlled laboratory conditions, how the complex factors of soil-water systems affect NMR relaxation times.

  11. Evaluating two irrigation controllers under subsurface drip irrigated tomato crop

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ghobari, H.M.; Mohammad, F.S.; El Marazky, M.S.A.

    2016-07-01

    Smart systems could be used to improve irrigation scheduling and save water under Saudi Arabia’s present water crisis scenario. This study investigated two types of evapotranspiration-based smart irrigation controllers, SmartLine and Hunter Pro-C2, as promising tools for scheduling irrigation and quantifying plants’ water requirements to achieve water savings. The effectiveness of these technologies in reducing the amount of irrigation water was compared with the conventional irrigation scheduling method as a control treatment. The two smart irrigation sensors were used for subsurface irrigation of a tomato crop (cv. Nema) in an arid region. The results showed that the smart controllers significantly reduced the amount of applied water and increased the crop yield. In general, the Hunter Pro-C2 system saved the highest amount of water and produced the highest crop yield, resulting in the highest water irrigation efficiency compared with the SmartLine controller and the traditional irrigation schedule. It can be concluded that the application of advanced scheduling irrigation techniques such as the Hunter controller under arid conditions can realise economic benefits by saving large amounts of irrigation water.

  12. Subsurface Ectomycorrhizal Fungi: A New Source of Atmospheric Methyl Halides?

    Science.gov (United States)

    Treseder, K. K.; Redeker, K. R.; Allen, M. F.

    2001-12-01

    Incomplete source budgets for methyl halides---compounds that release inorganic halogen radicals which, in turn, catalyze atmospheric ozone depletion---limit our abilities to predict the fate of the stratospheric ozone layer. We tested the ability ectomycorrhizal fungi to produce methyl bromide and methyl iodide. These fungi are abundant in temperate forests, where they colonize tree roots and provide nutrients to their symbiotic plants in exchange for carbon compounds. The observed range of emissions from seven different species in culture is 0.001- to 100-μ g g-1 fungi d-1 for methyl bromide, and 0.5- to 500-μ g g-1 fungi d-1 for methyl iodide. While methyl chloride was not specifically tested, large emissions were observed from several species with little to no emissions observed from others. Further analyses of the effects of substrate concentration, headspace concentration, and temperature were performed on the species Cenococcum geophilum, one of the most abundant ectomycorrhizal fungi. Our results suggest that subsurface fungal emissions may be a significant global source of methyl halides.

  13. Water potential and starvation stress in deep subsurface microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Kieft, T.L.; Rosacker, L.L.; Willcox, D.; Franklin, A.J.

    1990-01-01

    Nine intact core samples, collected aseptically from depths of 10--436 m near the Savannah River Plant in South Carolina, were tested for water potential, microbial numbers, and microbial activity. Although all samples were collected from below the water table, two samples (a Pee Dee clay from 238 m and a Middendorf clay from 324 m) showed unsaturated conditions ({minus}2.7 and {minus}2.1 MPa, respectively). Both of these samples had very low numbers of culturable cells, low microbial biomass (ATP assay), and low microbial activities (measured as respiration), suggesting that low metric waterpotentials in these strata are limiting factors to microorganisms. An Acinetobacter sp. isolated from the 324 m depth was found to maintain viability under starvation conditions in sterilized aquifer material, even when subjected to severe desiccation ({minus}22 MPa). A Pseudomonas sp., with the ability to oxidize thiosulfate to sulfate, was isolated from the 378 m Middendorf clay sample. This organism survived nutrient deprivation reasonably well; however, the presence of thiosulfate appeared to interfere with its normal ability to maintain viability by endogenous metabolism. Cells cultured in the presence of thiosulfate did not undergo dwarfing and cell viability declines. These are two examples of indigenous subsurface microorganisms, each with different adaptations for long-term survival under conditions of desiccation and/or starvation.

  14. Water potential and starvation stress in deep subsurface microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Kieft, T.L.; Rosacker, L.L.; Willcox, D.; Franklin, A.J.

    1990-12-31

    Nine intact core samples, collected aseptically from depths of 10--436 m near the Savannah River Plant in South Carolina, were tested for water potential, microbial numbers, and microbial activity. Although all samples were collected from below the water table, two samples (a Pee Dee clay from 238 m and a Middendorf clay from 324 m) showed unsaturated conditions ({minus}2.7 and {minus}2.1 MPa, respectively). Both of these samples had very low numbers of culturable cells, low microbial biomass (ATP assay), and low microbial activities (measured as respiration), suggesting that low metric waterpotentials in these strata are limiting factors to microorganisms. An Acinetobacter sp. isolated from the 324 m depth was found to maintain viability under starvation conditions in sterilized aquifer material, even when subjected to severe desiccation ({minus}22 MPa). A Pseudomonas sp., with the ability to oxidize thiosulfate to sulfate, was isolated from the 378 m Middendorf clay sample. This organism survived nutrient deprivation reasonably well; however, the presence of thiosulfate appeared to interfere with its normal ability to maintain viability by endogenous metabolism. Cells cultured in the presence of thiosulfate did not undergo dwarfing and cell viability declines. These are two examples of indigenous subsurface microorganisms, each with different adaptations for long-term survival under conditions of desiccation and/or starvation.

  15. Estimation of subsurface geomodels by multi-objective stochastic optimization

    Science.gov (United States)

    Emami Niri, Mohammad; Lumley, David E.

    2016-06-01

    We present a new method to estimate subsurface geomodels using a multi-objective stochastic search technique that allows a variety of direct and indirect measurements to simultaneously constrain the earth model. Inherent uncertainties and noise in real data measurements may result in conflicting geological and geophysical datasets for a given area; a realistic earth model can then only be produced by combining the datasets in a defined optimal manner. One approach to solving this problem is by joint inversion of the various geological and/or geophysical datasets, and estimating an optimal model by optimizing a weighted linear combination of several separate objective functions which compare simulated and observed datasets. In the present work, we consider the joint inversion of multiple datasets for geomodel estimation, as a multi-objective optimization problem in which separate objective functions for each subset of the observed data are defined, followed by an unweighted simultaneous stochastic optimization to find the set of best compromise model solutions that fits the defined objectives, along the so-called ;Pareto front;. We demonstrate that geostatistically constrained initializations of the algorithm improves convergence speed and produces superior geomodel solutions. We apply our method to a 3D reservoir lithofacies model estimation problem which is constrained by a set of geological and geophysical data measurements and attributes, and assess the sensitivity of the resulting geomodels to changes in the parameters of the stochastic optimization algorithm and the presence of realistic seismic noise conditions.

  16. Evaluating two irrigation controllers under subsurface drip irrigated tomato crop

    Directory of Open Access Journals (Sweden)

    Hussein M. Al-Ghobari

    2016-12-01

    Full Text Available Smart systems could be used to improve irrigation scheduling and save water under Saudi Arabia’s present water crisis scenario. This study investigated two types of evapotranspiration-based smart irrigation controllers, SmartLine and Hunter Pro-C2, as promising tools for scheduling irrigation and quantifying plants’ water requirements to achieve water savings. The effectiveness of these technologies in reducing the amount of irrigation water was compared with the conventional irrigation scheduling method as a control treatment. The two smart irrigation sensors were used for subsurface irrigation of a tomato crop (cv. Nema in an arid region. The results showed that the smart controllers significantly reduced the amount of applied water and increased the crop yield. In general, the Hunter Pro-C2 system saved the highest amount of water and produced the highest crop yield, resulting in the highest water irrigation efficiency compared with the SmartLine controller and the traditional irrigation schedule. It can be concluded that the application of advanced scheduling irrigation techniques such as the Hunter controller under arid conditions can realise economic benefits by saving large amounts of irrigation water.

  17. Laser surface and subsurface modification of sapphire using femtosecond pulses

    Energy Technology Data Exchange (ETDEWEB)

    Eberle, G., E-mail: eberle@iwf.mavt.ethz.ch [Institute of Machine Tools and Manufacturing, ETH Zurich, Leonhardstrasse 21, 8092 Zurich (Switzerland); Schmidt, M. [Chair of Photonic Technologies, University of Erlangen-Nuremberg, Konrad-Zuse-Strasse 3-5, 91052 Erlangen (Germany); Pude, F. [Inspire AG, Technoparkstrasse 1, 8005 Zurich (Switzerland); Wegener, K. [Institute of Machine Tools and Manufacturing, ETH Zurich, Leonhardstrasse 21, 8092 Zurich (Switzerland); Inspire AG, Technoparkstrasse 1, 8005 Zurich (Switzerland)

    2016-08-15

    Highlights: • Single and multipulse ablation threshold of aluminium oxide is determined. • Laser ablation, and in-volume modification followed by wet etching are demonstrated. • Quality following laser processing and laser-material interactions are studied. - Abstract: Two methods to process sapphire using femtosecond laser pulses are demonstrated, namely ablation (surface), and in-volume laser modification followed by wet etching (subsurface). Firstly, the single and multipulse ablation threshold is determined and compared with previous literature results. A unique application of ablation is demonstrated by modifying the entrance aperture of water jet orifices. Laser ablation exhibits advantages in terms of geometric flexibility and resolution, however, defects in the form of edge outbreaks and poor surface quality are evident. Secondly, the role of material transformation, polarisation state and formation of multi-focus structures after in-volume laser modification is investigated in order to explain their influence during the wet etching process. Laser scanning and electron microscopy as well as electron backscatter diffraction measurements supported by ion beam polishing are used to better understand quality and laser-material interactions of the two demonstrated methods of processing.

  18. Low-Rank Kalman Filtering in Subsurface Contaminant Transport Models

    KAUST Repository

    El Gharamti, Mohamad

    2010-12-01

    Understanding the geology and the hydrology of the subsurface is important to model the fluid flow and the behavior of the contaminant. It is essential to have an accurate knowledge of the movement of the contaminants in the porous media in order to track them and later extract them from the aquifer. A two-dimensional flow model is studied and then applied on a linear contaminant transport model in the same porous medium. Because of possible different sources of uncertainties, the deterministic model by itself cannot give exact estimations for the future contaminant state. Incorporating observations in the model can guide it to the true state. This is usually done using the Kalman filter (KF) when the system is linear and the extended Kalman filter (EKF) when the system is nonlinear. To overcome the high computational cost required by the KF, we use the singular evolutive Kalman filter (SEKF) and the singular evolutive extended Kalman filter (SEEKF) approximations of the KF operating with low-rank covariance matrices. The SEKF can be implemented on large dimensional contaminant problems while the usage of the KF is not possible. Experimental results show that with perfect and imperfect models, the low rank filters can provide as much accurate estimates as the full KF but at much less computational cost. Localization can help the filter analysis as long as there are enough neighborhood data to the point being analyzed. Estimating the permeabilities of the aquifer is successfully tackled using both the EKF and the SEEKF.

  19. Passive control of fully developed turbulent flow by subsurface phonons

    Science.gov (United States)

    Hussein, Mahmoud; Biringen, Sedat; Hsieh, Alan; Bacquet, Clemence; Bastawrous, Mary

    2017-11-01

    Flow control is a central problem in fluid dynamics where the goal is to alter a flow's natural state to achieve improved performance, such as delay of laminar-to-turbulent transition or reduction of drag in a fully developed turbulent flow. Meeting this goal promises to significantly reduce the dependence on fossil fuels for global transport, impacting air and sea vehicles as well as long-range pipelines. In earlier work, we have shown that phonon motion underneath a surface interacting with a flow may be tuned to cause the flow to stabilize, or destabilize, as desired. This concept was demonstrated by simulating a fully developed plane Poiseuille (channel) flow whereby a small portion of an otherwise rigid wall is replaced with a one-dimensional phononic crystal. A Tollmien-Schlichting wave was introduced to the flow as an evolving disturbance. Upon tuning the frequency-dependent phase and amplitude relations of the surface of the phononic crystal that interfaces with the flow, an artificially introduced instability was shown to stabilize, or destabilize, as needed. In this work, we demonstrate the applicability of the phononic subsurface paradigm to the suppression of turbulence production events in fully developed turbulent flow.

  20. Sculpting Mountains: Interactive Terrain Modeling Based on Subsurface Geology.

    Science.gov (United States)

    Cordonnier, Guillaume; Cani, Marie-Paule; Benes, Bedrich; Braun, Jean; Galin, Eric

    2017-03-29

    Most mountain ranges are formed by the compression and folding of colliding tectonic plates. Subduction of one plate causes large-scale asymmetry while their layered composition (or stratigraphy) explains the multi-scale folded strata observed on real terrains. We introduce a novel interactive modeling technique to generate visually plausible, large scale terrains that capture these phenomena. Our method draws on both geological knowledge for consistency and on sculpting systems for user interaction. The user is provided hands-on control on the shape and motion of tectonic plates, represented using a new geologically-inspired model for the Earth crust. The model captures their volume preserving and complex folding behaviors under collision, causing mountains to grow. It generates a volumetric uplift map representing the growth rate of subsurface layers. Erosion and uplift movement are jointly simulated to generate the terrain. The stratigraphy allows us to render folded strata on eroded cliffs. We validated the usability of our sculpting interface through a user study, and compare the visual consistency of the earth crust model with geological simulation results and real terrains.

  1. [Optimization of aerobic/anaerobic subsurface flow constructed wetlands].

    Science.gov (United States)

    Li, Feng-Min; Shan, Shi; Li, Yuan-Yuan; Li, Yang; Wang, Zheng-Yu

    2012-02-01

    Previous studies showed that setting aerobic and anaerobic paragraph segments in the subsurface constructed wetlands (SFCWs) can improve the COD, NH4(+)-N, and TN removal rate, whereas the oxygen enrichment environment which produced by the artificial aeration could restrain the NO3(-)-N and NO2(-)-N removal process, and to a certain extent, inhibit the denitrification in SFCWs Therefore, in this research the structure and technology of SFCW with aerobic and anaerobic paragraph segments were optimized, by using the multi-point water inflow and setting the corresponding section for the extra pollutant removal. Results showed that with the hydraulic load of 0.06 m3 x (m2 x d)(-1), the COD, NH4(+)-N and TN removal efficiencies in the optimized SFCW achieved 91.6%, 100% and 87.7% respectively. COD/N increased to 10 speedily after the inflow supplement. The multi-point water inflow could add carbon sources, and simultaneously maximum utilization of wetland to remove pollutants. The optimized SFCW could achieve the purposes of purification process optimization, and provide theoretical basis and application foundation for improving the total nitrogen removal efficiency.

  2. Basic subsurface geology of the south-central Sacramento Valley

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, S.T.

    1978-01-01

    The generalized east-west cross section of the south-central Sacramento Valley shows the subsurface geology underlying the 27 miles long Interstate Highway 5 and State Highway 16 from the Yuba City turnoff I-5 to Esparto on Highway 16. The uppermost 2,000 to 3,000 ft of section consists of the Mid-Miocene Valley Springs, Upper Miocene Mehrten and Pliocene Upper Mehrten, and Tehama and the Pleistocene Red Bluff gravels. These formations are not differentiated on the section. A westward thickening wedge of Upper Cretaceous to Oligocene marine units underlies the continental deposits. Basement complexes are Sierran on the east and Coast Range on the west. The boundary between these basement assemblages probably underlies the area just to the east of Woodland. The east-west portion of I-5 parallels a break in the geology of the Sacramento Valley. To the north, the Martinez, H and T, Starkey sands, and Winters Formation are soon truncated by the unconformity at the base of the Capay Shale. These units are important gas reservoirs adjacent to the south of the highway. To the north, most production is from the Cretaceous F Zone.

  3. Subsurface thermal coagulation of tissues using near infrared lasers

    Science.gov (United States)

    Chang, Chun-Hung Jack

    Noninvasive laser therapy is currently limited primarily to cosmetic dermatological applications such as skin resurfacing, hair removal, tattoo removal and treatment of vascular birthmarks. In order to expand applications of noninvasive laser therapy, deeper optical penetration of laser radiation in tissue as well as more aggressive cooling of the tissue surface is necessary. The near-infrared laser wavelength of 1075 nm was found to be the optimal laser wavelength for creation of deep subsurface thermal lesions in liver tissue, ex vivo, with contact cooling, preserving a surface tissue layer of 2 mm. Monte Carlo light transport, heat transfer, and Arrhenius integral thermal damage simulations were conducted at this wavelength, showing good agreement between experiment and simulations. Building on the initial results, our goal is to develop new noninvasive laser therapies for application in urology, specifically for treatment of female stress urinary incontinence (SUI). Various laser balloon probes including side-firing and diffusing fibers were designed and tested for both transvaginal and transurethral approaches to treatment. The transvaginal approach showed the highest feasibility. To further increase optical penetration depth, various types and concentrations of optical clearing agents were also explored. Three cadavers studies were performed to investigate and demonstrate the feasibility of laser treatment for SUI.

  4. International Migration of Couples

    OpenAIRE

    Junge, Martin; Munk, Martin D.; Nikolka, Till; Poutvaara, Panu

    2017-01-01

    We analyze emigration and return decisions of Danish couples. Our main questions are how emigration and return migration decisions depend on education, earnings, and the number and age of children. We use register data on full population from 1982 to 2006, focusing on opposite-gender couples in which the female is aged 23 to 37, and the male 25 to 39. We find that power couples in which both are highly educated are most likely to emigrate, but also most likely to return. Couples in which only...

  5. Subsurface Contaminants Focus Area (SCFA) Lead Laboratory Providing Technical Assistance to the DOE Weapons Complex in Subsurface Contamination

    Energy Technology Data Exchange (ETDEWEB)

    Wright, J. A. Jr.; Corey, J. C.

    2002-02-27

    The Subsurface Contaminants Focus Area (SCFA), a DOE-HQ EM-50 organization, is hosted and managed at the Savannah River Site in Aiken, South Carolina. SCFA is an integrated program chartered to find technology and scientific solutions to address DOE subsurface environmental restoration problems throughout the DOE Weapons Complex. Since its inception in 1989, the SCFA program has resulted in a total of 269 deployments of 83 innovative technologies. Until recently, the primary thrust of the program has been to develop, demonstrate, and deploy those remediation technology alternatives that are solutions to technology needs identified by the DOE Sites. Over the last several years, the DOE Sites began to express a need not only for innovative technologies, but also for technical assistance. In response to this need, DOE-HQ EM-50, in collaboration with and in support of a Strategic Lab Council recommendation directed each of its Focus Areas to implement a Lead Laboratory Concept to enhance their technical capabilities. Because each Focus Area is unique as defined by the contrast in either the type of contaminants involved or the environments in which they are found, the Focus Areas were given latitude in how they set up and implemented the Lead Lab Concept. The configuration of choice for the SCFA was a Lead-Partner Lab arrangement. Savannah River Technology Center (SRTC) teamed with the SCFA as the Focus Area's Lead Laboratory. SRTC then partnered with the DOE National Laboratories to create a virtual consulting function within DOE. The National Laboratories were established to help solve the Nation's most difficult problems, drawing from a resource pool of the most talented and gifted scientists and engineers. Following that logic, SRTC, through the Lead-Partner Lab arrangement, has that same resource base to draw from to provide assistance to any SCFA DOE customer throughout the Complex. This paper briefly describes how this particular arrangement is

  6. Coupling a groundwater model with a land surface model to improve water and energy cycle simulation

    Directory of Open Access Journals (Sweden)

    W. Tian

    2012-12-01

    Full Text Available Water and energy cycles interact, making these two processes closely related. Land surface models (LSMs can describe the water and energy cycles on the land surface, but their description of the subsurface water processes is oversimplified, and lateral groundwater flow is ignored. Groundwater models (GWMs describe the dynamic movement of the subsurface water well, but they cannot depict the physical mechanisms of the evapotranspiration (ET process in detail. In this study, a coupled model of groundwater flow with a simple biosphere (GWSiB is developed based on the full coupling of a typical land surface model (SiB2 and a 3-D variably saturated groundwater model (AquiferFlow. In this coupled model, the infiltration, ET and energy transfer are simulated by SiB2 using the soil moisture results from the groundwater flow model. The infiltration and ET results are applied iteratively to drive the groundwater flow model. After the coupled model is built, a sensitivity test is first performed, and the effect of the groundwater depth and the hydraulic conductivity parameters on the ET are analyzed. The coupled model is then validated using measurements from two stations located in shallow and deep groundwater depth zones. Finally, the coupled model is applied to data from the middle reach of the Heihe River basin in the northwest of China to test the regional simulation capabilities of the model.

  7. Use of dewatered sludge as microbial inoculum of a subsurface ...

    African Journals Online (AJOL)

    brown earth and coal slag–based SWIS (Li et al., 2011c; Wang et al., 2010). Nitrification coupled with denitrification is the major removal process for nitrogen in SWIS. Nitrification and denitrification is usually affected by the nitrifying and denitrifying biomass, temperature, operational parameters and the characteristics of the ...

  8. Transport zonation limits coupled nitrification-denitrification in permeable sediments

    DEFF Research Database (Denmark)

    Kessler, Adam John; Glud, R.N.; Cardenas, M.B.

    2013-01-01

    Measurement of biogeochemical processes in permeable sediments (including the hyporheic zone) is difficult because of complex multidimensional advective transport. This is especially the case for nitrogen cycling, which involves several coupled redox-sensitive reactions. To provide detailed insig......- and N-15-N-2 gas. The measured two-dimensional profiles correlate with computational model simulations, showing a deep pool of N-2 gas forming, and being advected to the surface below ripple peaks. Further isotope pairing calculations on these data indicate that coupled nitrification......-denitrification is severely limited in permeable sediments because the flow and transport field limits interaction between oxic and anoxic pore water. The approach allowed for new detailed insight into subsurface denitrification zones in complex permeable sediments....

  9. Development and Testing of a Model to Assess Subsurface Moisture Gradients From Diurnal Surface Temperatures and Soil Thermophysical Properties

    Science.gov (United States)

    Griggs, L. E.; Arvidson, R. E.

    2002-12-01

    A one-dimensional, finite difference coupled heat and moisture transfer model for unsaturated zone porous media flow has been developed and tested. Inputs to the model include soil surface excursions, site topography, meteorological data, and detailed information about the soil thermophysical and hydraulic properties. Assuming homogeneity or knowledge of the stratification of the soil column and steady-state conditions (i.e. no recharge), the output is a profile of moisture gradients in the subsurface extending to the depth of diurnal fluctuations of moisture. This model primarily differs from existing one-dimensional heat and transport models in its incorporation of the 3-dimensional topography and diurnal shadowing of the study site and in its ability to provide information about relatively deep moisture profiles. These profiles are produced through the assumption of a moisture source (a water table or pseudo water table) at a given depth. The model was subject to sensitivity analyses and was calibrated in August 2002 in the Kau Desert, Hawaii, in an unvegetated area with layers of high moisture content in the subsurface. Field work consisted of 24 contiguous hours of monitoring soil surface temperature, meteorological data, and moisture content at several depths of the soil profile. Thermal conductivity of the soil was determined in situ, and field saturated hydraulic conductivity was determined with a Guelph permeameter. The other thermophysical and hydraulic soil properties of interest (specific heat, moisture retention curve, bulk density, porosity, grain axes, and van Genuchten parameters) were determined through laboratory experimentation. Results from the calibration exercise will be presented.

  10. The impact of multi-decadal sub-surface circulation changes on sea surface chlorophyll patterns in the tropical Pacific

    Science.gov (United States)

    Schollaert Uz, S.; Busalacchi, A. J.; Smith, T. M.; Evans, M. N.; Brown, C.; Hackert, E. C.; Wang, X.

    2016-12-01

    The tropical Pacific is a region of strong forcing where physical oceanography primarily controls biological variability over the seasonal to interannual time scales observed since dedicated ocean color satellite remote sensing began in 1997. To quantify how multi-decadal, climate-scale changes impact marine biological dynamics, we used the correlation with sea-surface temperature and height to reconstruct a 50-year time series of surface chlorophyll concentrations. The reconstruction demonstrates greatest skill away from the coast and within 10o of the equator where chlorophyll variance is greatest and primarily associated with El Niño Southern Oscillation (ENSO) dynamics and secondarily associated with decadal variability. We observe significant basin-wide differences between east and central Pacific events when the El Niño events are strong: chlorophyll increases with La Niña and decreases with El Niño, with larger declines east of 180o for remotely-forced east Pacific events and west of 180o for locally-forced central Pacific events. Chlorophyll variations also reflect the physical dynamics of Pacific decadal variability with small but significant differences between cool and warm eras: consistent with advection variability west of 180o and likely driven by subsurface changes in the nutricline depth between 110-140oW. Comparisons with output from a fully-coupled biogeochemical model support the hypothesis that this anomalous region is controlled by lower frequency changes in subsurface circulation patterns that transport nutrients to the surface. Basin-wide chlorophyll distributions exhibiting spatial heterogeneity in response to multi-decadal climate forcing imply similar long-term changes in phytoplankton productivity, with implications for the marine food web and the ocean's role as a carbon sink.

  11. Using dynamic flux chambers to estimate the natural attenuation rates in the subsurface at petroleum contaminated sites.

    Science.gov (United States)

    Verginelli, Iason; Pecoraro, Roberto; Baciocchi, Renato

    2017-11-17

    In this work, we introduce a screening method for the evaluation of the natural attenuation rates in the subsurface at sites contaminated by petroleum hydrocarbons. The method is based on the combination of the data obtained from standard source characterization with dynamic flux chambers measurements. The natural attenuation rates are calculated as difference between the flux of contaminants estimated with a non-reactive diffusive model starting from the concentrations of the contaminants detected in the source (soil and/or groundwater) and the effective emission rate of the contaminants measured using dynamic flux chambers installed at ground level. The reliability of this approach was tested in a contaminated site characterized by the presence of BTEX in soil and groundwater. Namely, the BTEX emission rates from the subsurface were measured in 4 seasonal campaigns using dynamic flux chambers installed in 14 sampling points. The comparison of measured fluxes with those predicted using a non-reactive diffusive model, starting from the source concentrations, showed that, in line with other recent studies, the modelling approach can overestimate the expected outdoor concentration of petroleum hydrocarbons even up to 4 orders of magnitude. On the other hand, by coupling the measured data with the fluxes estimated with the diffusive non-reactive model, it was possible to perform a mass balance to evaluate the natural attenuation loss rates of petroleum hydrocarbons during the migration from the source to ground level. Based on this comparison, the estimated BTEX loss rates in the test site were up to almost 0.5kg/year/m2. These rates are in line with the values reported in the recent literature for natural source zone depletion. In short, the method presented in this work can represent an easy-to-use and cost-effective option that can provide a further line of evidence of natural attenuation rates expected at contaminated sites. Copyright © 2017 Elsevier B.V. All

  12. Modelling of real area of contact between tool and workpiece in metal forming processes including the influence of subsurface deformation

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Martins, Paulo A. F.; Bay, Niels Oluf

    2016-01-01

    New equipment for testing asperity deformation at various normal loads and subsurface elongations is presented. Resulting real contact area ratios increase heavily with increasing subsurface expansion due to lowered yield pressure on the asperities when imposing subsurface normal stress parallel ...... for estimating friction in the numerical modelling of metal forming processes.......New equipment for testing asperity deformation at various normal loads and subsurface elongations is presented. Resulting real contact area ratios increase heavily with increasing subsurface expansion due to lowered yield pressure on the asperities when imposing subsurface normal stress parallel...... to the surface. Finite element modelling supports the presentation and contributes by extrapolation of results to complete the mapping of contact area as function of normal pressure and one-directional subsurface strain parallel to the surface. Improved modelling of the real contact area is the basis...

  13. Subsurface Scattering-Based Object Rendering Techniques for Real-Time Smartphone Games

    Directory of Open Access Journals (Sweden)

    Won-Sun Lee

    2014-01-01

    Full Text Available Subsurface scattering that simulates the path of a light through the material in a scene is one of the advanced rendering techniques in the field of computer graphics society. Since it takes a number of long operations, it cannot be easily implemented in real-time smartphone games. In this paper, we propose a subsurface scattering-based object rendering technique that is optimized for smartphone games. We employ our subsurface scattering method that is utilized for a real-time smartphone game. And an example game is designed to validate how the proposed method can be operated seamlessly in real time. Finally, we show the comparison results between bidirectional reflectance distribution function, bidirectional scattering distribution function, and our proposed subsurface scattering method on a smartphone game.

  14. Eruptions at Lone Star geyser, Yellowstone National Park, USA: 2. Constraints on subsurface dynamics

    National Research Council Canada - National Science Library

    Vandemeulebrouck, Jean; Sohn, Robert A; Rudolph, Maxwell L; Hurwitz, Shaul; Manga, Michael; Johnston, Malcolm J. S; Soule, S. Adam; McPhee, Darcy; Glen, Jonathan M. G; Karlstrom, Leif; Murphy, Fred

    2014-01-01

    We use seismic, tilt, lidar, thermal, and gravity data from 32 consecutive eruption cycles of Lone Star geyser in Yellowstone National Park to identify key subsurface processes throughout the geyser's eruption cycle...

  15. Subsurface oscillations at an oceanic station in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, Y.V.B.; Sarma, M.S.S.; Charyulu, R.J.K.; Rao, D.P.

    Surface wind, atmospheric pressure and the temperature profiles in the upper layers at an oceanic station off west of Andaman Island in the Bay of Bengal have been analysed to examine the causes for the observed subsurface oscillations...

  16. Subsurface geology off Bombay with paleoclimatic inferences interpreted from shallow seismic profiles

    Digital Repository Service at National Institute of Oceanography (India)

    Bhattacharya, G.C.; Almeida, F.; Vora, K.H.; Siddiquie, H.N.

    High resolution seismic reflection profiles nearshore areas off Bombay provide information on subsurface geology and permit certain paleoclimatic inferences. Three sedimentary units overlie the acoustic basement: late Pleistocene consolidated...

  17. Nondestructive evaluation of the condition of subsurface drainage in pavements using ground penetrating radar (GPR).

    Science.gov (United States)

    2013-11-11

    Subsurface drainage features are routinely incorporated in the design of pavement systems as they are believed to increase pavement service life provided that they are installed correctly and maintained. Maintenance, however, is challenging in that l...

  18. Deep Ground Penetrating Radar (GPR) WIPL-D Models of Buried Sub-Surface Radiators

    National Research Council Canada - National Science Library

    Norgard, John D; Wicks, Michael C; Musselman, Randy L

    2005-01-01

    .... A new Ground Penetrating Radar (GPR) concept is proposed in this paper to use subsurface radiators, delivered as earth penetrating non-explosive, electronic e-bombs, as the source of strong radiated transmissions for GPR experiments...

  19. Augmented In Situ Subsurface Bioremediation Process™BIO-REM, Inc. - Demonstration Bulletin

    Science.gov (United States)

    The Augmented In Situ Subsurface Bioremediation Process™ developed by BIO-REM, Inc., uses microaerophilic bacteria and micronutrients (H-10) and surface tension depressants/penetrants for the treatment of hydrocarbon contaminated soils and groundwater. The bacteria utilize hydroc...

  20. ALACE subsurface drifter data in South Pacific, for March 1995 (NODC Accession 9500149)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The ALACE (Autonomous LAgrangian Circulation Explorer) is a subsurface drifter, periodically rising to the surface to relay data to ARGOS. Instrument location is...