Science.gov

Sample records for long-term performance assessments

  1. Benefits of a Biological Monitoring Program for Assessing Remediation Performance and Long-Term Stewardship - 12272

    SciTech Connect

    Peterson, Mark

    2012-07-01

    The Biological Monitoring and Abatement Program (BMAP) is a long-running program that was designed to evaluate biological conditions and trends in waters downstream of Department of Energy (DOE) facilities in Oak Ridge, Tennessee. BMAP monitoring has focused on aquatic pathways from sources to biota, which is consistent with the sites' clean water regulatory focus and the overall cleanup strategy which divided remediation areas into watershed administrative units. Specific programmatic goals include evaluating operational and legacy impacts to nearby streams and the effectiveness of implemented remediation strategies at the sites. The program is characterized by consistent, long-term sampling and analysis methods in a multidisciplinary and quantitative framework. Quantitative sampling has shown conclusively that at most Oak Ridge stream sites, fish and aquatic macro-invertebrate communities have improved considerably since the 1980s. Monitoring of mercury and PCBs in fish has shown that remedial and abatement actions have also improved stream conditions, although in some cases biological monitoring suggests further actions are needed. Follow-up investigations have been implemented by BMAP to identify sources or causes, consistent with an adaptive management approach. Biological monitoring results to date have not only been used to assess regulatory compliance, but have provided additional benefits in helping address other components of the DOE's mission, including facility operations, natural resource, and scientific goals. As a result the program has become a key measure of long-term trends in environmental conditions and of high value to the Oak Ridge environmental management community, regulators, and the public. Some of the BMAP lessons learned may be of value in the design, implementation, and application of other long-term monitoring and stewardship programs, and assist environmental managers in the assessment and prediction of the effectiveness of remedial

  2. Assessment of the effect of castration upon arrival on long-term growth performance of stocker cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Existing records were used to quantify the impact of castration and dehorning of calves upon arrival at a stocker unit on long-term growth performance and morbidity. Male calves (n = 1,105; BW = 186 ± 24 kg) received over a three-year period were used to assess the effects of castration and dehorni...

  3. The Performance of a Method for the Long-Term Equating of Mixed-Format Assessment

    ERIC Educational Resources Information Center

    Kamata, Akihito; Tate, Richard

    2005-01-01

    The goal of this study was the development of a procedure to predict the equating error associated with the long-term equating method of Tate (2003) for mixed-format tests. An expression for the determination of the error of an equating based on multiple links using the error for the component links was derived and illustrated with simulated data.…

  4. Performance considerations in long-term spaceflight

    NASA Technical Reports Server (NTRS)

    Akins, F. R.

    1979-01-01

    Maintenance of skilled performance during extended space flight is of critical importance to both the health and safety of crew members and to the overall success of mission goals. An examination of long term effects and performance requirements is therefore a factor of immense importance to the planning of future missions. Factors that were investigated include: definition of performance categories to be investigated; methods for assessing and predicting performance levels; in-flight factors which can affect performance; and factors pertinent to the maintenance of skilled performance.

  5. Incorporating long-term climate change in performance assessment for the Waste Isolation Pilot Plant

    SciTech Connect

    Swift, P.N.; Baker, B.L.; Economy, K.; Garner, J.W.; Helton, J.C.; Rudeen, D.K.

    1994-03-01

    The United States Department of Energy (DOE) is developing the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico for the disposal of transuranic wastes generated by defense programs. Applicable regulations (40 CFR 191) require the DOE to evaluate disposal-system performance for 10,000 yr. Climatic changes may affect performance by altering groundwater flow. Paleoclimatic data from southeastern New Mexico and the surrounding area indicate that the wettest and coolest Quaternary climate at the site can be represented by that at the last glacial maximum, when mean annual precipitation was approximately twice that of the present. The hottest and driest climates have been similar to that of the present. The regularity of global glacial cycles during the late Pleistocene confirms that the climate of the last glacial maximum is suitable for use as a cooler and wetter bound for variability during the next 10,000 yr. Climate variability is incorporated into groundwater-flow modeling for WIPP PA by causing hydraulic head in a portion of the model-domain boundary to rise to the ground surface with hypothetical increases in precipitation during the next 10,000 yr. Variability in modeled disposal-system performance introduced by allowing had values to vary over this range is insignificant compared to variability resulting from other causes, including incomplete understanding of transport processes. Preliminary performance assessments suggest that climate variability will not affect regulatory compliance.

  6. Incorporating long-term climate change in performance assessment for the Waste Isolation Pilot Plant

    SciTech Connect

    Swift, P.N.; Baker, B.L.; Economy, K.; Garner, J.W.; Helton, J.C.; Rudeen, D.K.

    1993-09-18

    The United States Department of Energy (DOE) is developing the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico for the disposal of transuranic wastes generated by defense programs. Applicable regulations (40 CFR 191) require the DOE to evaluate disposal-system performance for 10,000 yr. Climatic changes may affect performance by altering groundwater flow. Paleoclimatic data from southeastern New Mexico and the surrounding area indicate that the wettest and coolest Quaternary climate at the site can be represented by that at the last glacial maximum, when mean annual precipitation was approximately twice that of the present. The hottest and driest climates have been similar to that of the present. The regularity of global glacial cycles during the late Pleistocene confirms that the climate of the last glacial maximum is suitable for use as a cooler and wetter bound for variability during the next 10,000 yr. Climate variability is incorporated into groundwater-flow modeling for WIPP PA by causing hydraulic head in a portion of the model-domain boundary to rise to the ground surface with hypothetical increases in precipitation during the next 10,000 yr. Variability in modeled disposal-system performance introduced by allowing head values to vary over this range is insignificant compared to variability resulting from other causes, including incomplete understanding of transport processes. Preliminary performance assessments suggest that climate variability will not affect regulatory compliance.

  7. Long term performance session summary

    SciTech Connect

    Hanauer, S.

    1996-05-01

    This paper presents brief summaries of reports given on plutonium disposal. Topics include: performance of waste forms; glass leaching; ceramic leaching; safeguards and security issues; safeguards of vitrification; and proliferation risks of geologic disposal.

  8. Approaches to long-term performance assessment of deep underground disposal of radioactive wastes: A European perspective

    SciTech Connect

    Sumerling, T.J.; Read, D.

    1993-12-31

    The aim of long-term performance assessment (PA) is generally to develop confidence that the disposal system will perform within certain bounds and give rise to acceptably low impacts or risks. The PA procedure must be able to deal with: (1) uncertainty due to incomplete understanding of the relevant processes; (2) uncertainty due to limited sampling of the structures and characteristics of the system and especially the geological media; (3) uncertainty about future conditions and processes leading to changes in the engineered barriers and natural environment that may affect radionuclide release, transport and exposure pathways. A number of approaches have been taken to solving the problem of how to deal with such uncertainties. The differences in approach may be due to the stage of project development, differences in national regulatory guidance and the different roles of the implementor and the regulator. This paper examines the roles of the implementor and regulator and discusses possible approaches appropriate to both points of view.

  9. Sandia National Laboratories performance assessment methodology for long-term environmental programs : the history of nuclear waste management.

    SciTech Connect

    Marietta, Melvin Gary; Anderson, D. Richard; Bonano, Evaristo J.; Meacham, Paul Gregory

    2011-11-01

    Sandia National Laboratories (SNL) is the world leader in the development of the detailed science underpinning the application of a probabilistic risk assessment methodology, referred to in this report as performance assessment (PA), for (1) understanding and forecasting the long-term behavior of a radioactive waste disposal system, (2) estimating the ability of the disposal system and its various components to isolate the waste, (3) developing regulations, (4) implementing programs to estimate the safety that the system can afford to individuals and to the environment, and (5) demonstrating compliance with the attendant regulatory requirements. This report documents the evolution of the SNL PA methodology from inception in the mid-1970s, summarizing major SNL PA applications including: the Subseabed Disposal Project PAs for high-level radioactive waste; the Waste Isolation Pilot Plant PAs for disposal of defense transuranic waste; the Yucca Mountain Project total system PAs for deep geologic disposal of spent nuclear fuel and high-level radioactive waste; PAs for the Greater Confinement Borehole Disposal boreholes at the Nevada National Security Site; and PA evaluations for disposal of high-level wastes and Department of Energy spent nuclear fuels stored at Idaho National Laboratory. In addition, the report summarizes smaller PA programs for long-term cover systems implemented for the Monticello, Utah, mill-tailings repository; a PA for the SNL Mixed Waste Landfill in support of environmental restoration; PA support for radioactive waste management efforts in Egypt, Iraq, and Taiwan; and, most recently, PAs for analysis of alternative high-level radioactive waste disposal strategies including repositories deep borehole disposal and geologic repositories in shale and granite. Finally, this report summarizes the extension of the PA methodology for radioactive waste disposal toward development of an enhanced PA system for carbon sequestration and storage systems

  10. Long-term Short Implants Performance: Systematic Review and Meta-Analysis of the Essential Assessment Parameters.

    PubMed

    Gonçalves, Thais Marques Simek Vega; Bortolini, Sergio; Martinolli, Matteo; Alfenas, Bruna Fernandes Moreira; Peruzzo, Daiane Cristina; Natali, Alfredo; Berzaghi, Andrea; Garcia, Renata Cunha Matheus Rodrigues

    2015-01-01

    Lack of standard criteria in the outcome assessment makes it difficult to draw conclusions on the clinical performance of short implants and, under these circumstances, determine the reasons for implant failure. This study evaluated, through a systematic review of the literature and meta-analysis, the essential parameters required to assess the long-term clinical performance of short and extra-short implants. Electronic databases (Pubmed-MEDLINE, Cochrane Library Database, Embase, and Lilacs) were searched by two independent reviewers, without language limitation, to identify eligible papers. References from the selected articles were also reviewed. The review included clinical trials involving short dental implants placed in humans, published between January 2000 and March 2014, which described the parameters applied for outcome's measurements and provided data on survival rates. Thirteen methodologically acceptable studies were selected and 24 parameters were identified. The most frequent parameters assessed were the marginal bone loss and the cumulative implant survival rate, followed by implant failure rate and biological complications such as bleeding on probing and probing pocket depths. Only cumulative implant survival rate data allows meta-analysis revealing a positive effect size (from 0.052 (fixed) to 0.042 (random)), which means that short implant appears to be a successful treatment option. Mechanical complications and crown-to-implant (C/I) ratio measurement were also commonly described, however, considering the available evidence; no strong conclusions could be drawn since different methods were used to assess each parameter. By means of this literature review, a standard evaluation scheme is proposed, being helpful to regiment further investigations and comparisons on future studies. PMID:26312967

  11. CUMAS: a seafloor multi-sensor module for volcanic hazard monitoring - First long-term experiment and performance assessment

    NASA Astrophysics Data System (ADS)

    Iannaccone, G.; Guardato, S.; Vassallo, M.; Stabile, T. A.; Elia, L.; Beranzoli, L.

    2009-12-01

    providing continuous geophysical data to the Monitoring Center of the Campi Flegrei volcanic areas, managed by the Istituto Nazionale di Geofisica e Vulcanologia. The long-term operational performance of CUMAS is presented here, together with the first results from the analysis of the geophysical long time-series acquired. Examples of the acquired signals, especially geophysical data, will be presented to point out the high quality in term of signal-to-noise ratio. In particular, earthquake recordings obtained from the hydrophone resulted of comparable quality to the seismic data acquired on land by the permanent network, thus demonstrating the suitability of hydrophones to monitor the seismic activity of the caldera.

  12. Long term performance of radon mitigation systems

    SciTech Connect

    Prill, R.; Fisk, W.J.

    2002-03-01

    Researchers installed radon mitigation systems in 12 houses in Spokane, Washington and Coeur d'Alene, Idaho during the heating season 1985--1986 and continued to monitor indoor radon quarterly and annually for ten years. The mitigation systems included active sub-slab ventilation, basement over-pressurization, and crawlspace isolation and ventilation. The occupants reported various operational problems with these early mitigation systems. The long-term radon measurements were essential to track the effectiveness of the mitigation systems over time. All 12 homes were visited during the second year of the study, while a second set 5 homes was visited during the fifth year to determine the cause(s) of increased radon in the homes. During these visits, the mitigation systems were inspected and measurements of system performance were made. Maintenance and modifications were performed to improve system performance in these homes.

  13. The assessment of long-term orbital debris models

    NASA Technical Reports Server (NTRS)

    Jonas, F. M.; Yates, K. W.

    1992-01-01

    Existing long-term orbital debris models are assessed as a first step in the Air Force's effort to develop an Air Force long-term orbital debris model which can perform the following functions: (1) operate with the necessary accuracy at the relevant altitudes and orbital parameters; (2) benefit from new Air Force and non-Air Force debris measurements; and (3) accommodate current and future Air Force space scenarios. Model assessment results are shown for the NASA engineering model. The status of the NASA EVOLVE model assessment is discussed.

  14. LONG TERM HYDROLOGICAL IMPACT ASSESSMENT (LTHIA)

    EPA Science Inventory

    LTHIA is a universal Urban Sprawl analysis tool that is available to all at no charge through the Internet. It estimates impacts on runoff, recharge and nonpoint source pollution resulting from past or proposed land use changes. It gives long-term average annual runoff for a lan...

  15. AEPAT: SOFTWARE FOR ASSESSING AGRONOMIC AND ENVIRONMENTAL PERFORMANCE OF MANAGEMENT PRACTICES IN LONG-TERM AGROECOSYSTEM EXPERIMENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Approaches to assess the effects of management practices on agroecosystem functions are needed to determine the relative sustainability of agricultural management systems. This paper describes a computer program designed to assess the relative sustainability of management practices using agronomic ...

  16. Long-term assessment of best cathode position to maximise microbial fuel cell performance in horizontal subsurface flow constructed wetlands.

    PubMed

    Corbella, Clara; Garfí, Marianna; Puigagut, Jaume

    2016-09-01

    The cathode of microbial fuel cells (MFCs) implemented in constructed wetlands (CWs) is generally set in close contact with water surface to provide a rich oxygen environment. However, water level variations caused by plants evapotranspiration in CWs might decrease MFC performance by limiting oxygen transfer to the cathode. Main objective of this work was to quantify the effect of water level variation on MFC performance implemented in HSSF CW. For the purpose of this work two MFCs were implemented within a HSSF CW pilot plant fed with primary treated domestic wastewater. Cell voltage (Ecell) and the relative distance between the cathode and the water level were recorded for one year. Results showed that Ecell was greatly influenced by the relative distance between the cathode and the water level, giving an optimal cathode position of about 1 to 2cm above water level. Both water level variation and Ecell were daily and seasonal dependent, showing a pronounced day/night variation during warm periods and showing almost no daily variation during cold periods. Energy production under pronounced daily water level variation was 40% lower (80±56mWh/m(2)·day) than under low water level variation (131±61mWh/m(2)·day). Main conclusion of the present work is that of the performance of MFC implemented in HSSF CW is highly dependent on plants evapotranspiration. Therefore, MFC that are to be implemented in CWs shall be designed to be able to cope with pronounced water level variations. PMID:27151501

  17. Long term performance stability of silicon sensors

    NASA Astrophysics Data System (ADS)

    Mori, R.; Betancourt, C.; Kühn, S.; Hauser, M.; Messmer, I.; Hasenfratz, A.; Thomas, M.; Lohwasser, K.; Parzefall, U.; Jakobs, K.

    2015-10-01

    The HL-LHC investigations on silicon particle sensor performance are carried out with the intention to reproduce the harsh environments foreseen, but usually in individual short measurements. Recently, several groups have observed a decrease in the charge collection of silicon strip sensors after several days, in particular on sensors showing charge multiplication. This phenomenon has been explained with a surface effect, the increase of charge sharing due to the increment of positive charge in the silicon oxide coming from the source used for charge collection measurements. Observing a similar behaviour in other sensors for which we can exclude this surface effect, we propose and investigate alternative explanations, namely trapping related effects (change of polarization) and annealing related effects. Several n-on-p strip sensors, as-processed and irradiated with protons and neutrons up to 5 ×1015neq /cm2, have been subjected to charge collection efficiency measurements for several days, while parameters like the impedance have been monitored. The probable stressing conditions have been changed in an attempt to recover the collected charge in case of a decrease. The results show that for the investigated sensors the effect of charge sharing induced by a radioactive source is not important, and a main detrimental factor is due to very high voltage, while at lower voltages the performance is stable.

  18. The long-term performance of DXA bone densitometers.

    PubMed

    Wells, J; Ryan, P J

    2000-07-01

    Long-term performance of a bone mass measuring device is an important criterion when considering the purchase of such equipment and has been regarded as an important feature of dual X-ray absorptiometry (DXA). The performance of a 6-year-old bone densitometer, the Lunar DPX alpha, which has undertaken 1500 scans annually over this period, was assessed. The short-term coefficient of variation calculated from 15 measurements with repositioning on a single day, using the Lunar aluminium phantom, was 0.242%. Long-term precision, also calculated by the coefficient of variation, was 0.548%. The manufacturer's quality control (QC) procedure was performed daily and allowed the machine to be used except on 15 occasions when bone density measurements could be acquired after rebooting. However, a 2.2% shift in phantom values occurred in July 1996 owing to a photomultiplier tube failure, but this did not produce a failure in the Lunar QC. The optical disc drive was replaced in July 1997. The machine failed to back up on six occasions over the last 2 years owing to software corruption and the acquired femur data were not saved on seven occasions owing to overloading of the memory buffer. In conclusion, expected hardware failure and minor software problems have occurred. We were concerned that the manufacturer's QC failed to detect a 2% shift in the phantom bone mineral density values and recommend regular measurements of the Lunar aluminum phantom in addition to the daily QC measurement of the tissue-equivalent block. We were nevertheless impressed by the long-term stability and reproducibility of the Lunar DPX alpha. PMID:11089465

  19. Instrumentation of bridges for long-term performance monitoring

    NASA Astrophysics Data System (ADS)

    Feng, Maria Q.; Kim, Doo-Kie; Sheng, Li-Hong; Fiji, Leonard M.; Kim, Yoo J.

    2001-08-01

    As the state of the art in bridge design is advancing toward the performance-based design, it becomes increasingly important to monitor and evaluate the long-term structural performance of bridges, including strains in critical structural members, soil pressures on the abutment back walls and footings, accelerations on the decks and bents, etc. Such information is essential in developing new performance criteria for design. In this research, sensor systems for long-term structural performance monitoring have been installed on two new highway bridges on Orange County, California: the Jamboree Road Overcrossing and the West Street On-Ramp.

  20. Stirling engine - Approach for long-term durability assessment

    NASA Technical Reports Server (NTRS)

    Tong, Michael T.; Bartolotta, Paul A.; Halford, Gary R.; Freed, Alan D.

    1992-01-01

    The approach employed by NASA Lewis for the long-term durability assessment of the Stirling engine hot-section components is summarized. The approach consists of: preliminary structural assessment; development of a viscoplastic constitutive model to accurately determine material behavior under high-temperature thermomechanical loads; an experimental program to characterize material constants for the viscoplastic constitutive model; finite-element thermal analysis and structural analysis using a viscoplastic constitutive model to obtain stress/strain/temperature at the critical location of the hot-section components for life assessment; and development of a life prediction model applicable for long-term durability assessment at high temperatures. The approach should aid in the provision of long-term structural durability and reliability of Stirling engines.

  1. Assessing the performances of low impact development alternatives by long-term simulation for a semi-arid area in Tianjin, northern China.

    PubMed

    Huang, Jinhui Jeanne; Li, Yu; Niu, Shuai; Zhou, Shu H

    2014-01-01

    For areas that are urbanized rapidly, the practice of low impact development (LID) has gained an important place in stormwater management and urban planning due to its capability and beneficial effects in restoring the original hydrological cycle. The performances of LID alternatives can vary substantially due to different climate conditions. This study investigated the performances of five LID alternatives under a semi-arid climate in northern China on water balance and flood control. A numerical model, Storm Water Management Model version 5 (US Environmental Protection Agency), was employed to run 10 years' rainfall events for these objectives. Two evaluation methods were proposed in this study: the efficiency index for water balance and a performance radar chart. The investigation of the five LID alternatives revealed that these LID alternatives functioned differently in flood control and water balance, and porous pavement performed best in all indices except the lag time. The two evaluation methods, in conjunction with the long-term numerical simulation, can facilitate design and decision making by providing a clear picture of the performance and functions for these LID alternatives. PMID:25500462

  2. The Future Through the Past: The Use of Analog Sites for Design Criteria and Long Term Performance Assessment of Evapotranspiration Landfill Covers

    SciTech Connect

    Shafer, D. S.; Miller, J. J.; Young, M. H.; Edwards, S. C.; Rawlinson, S. E.

    2002-02-26

    There is growing support for using evapotranspiration (ET) covers for closure of low-level waste (LLW) and other types of waste disposal sites, particularly in the lower latitude arid regions of the western United States. At the Nevada Test Site (NTS), monolayer ET covers are the baseline technology for closure of LLW and mixed LLW cells. To better predict the long-term performance of monolayer ET covers, as well as to identify design criteria that will potentially improve their performance, the properties of, and processes occurring on, analog sites for ET covers on the NTS are being studied. The project is funded through the Subsurface Contaminants Focus Area of the U.S. Department of Energy. Four analog sites on the NTS have been selected to predict performance of ET covers over a 1,000-year compliance period. Two sites are relatively recently disturbed (within the last 50 years) and have been selected to evaluate processes and changes on ET covers for the early period after active cover maintenance is discontinued. Two other sites, late to mid-Holocene in age, are intended as analogs for the end of the compliance period (1,000 years or more); both surfaces are abandoned alluvial/colluvial deposits. The history of the early post-institutional control analog sites are being evaluated by an archaeologist to help determine when the sites were last disturbed or modified, and the mode of disturbance to help set baseline conditions. Similar to other ''landforms,'' ET covers will evolve over time because of pedogenic, biotic, and climatic processes. Properties of analog sites that could affect ET water balance performance will be evaluated to help understand ET cover performance over time.

  3. Long-term assessment of residential radon-mitigation systems

    SciTech Connect

    Nitschke, I.A.; Clarkin, M.E. ); Rizzuto, J.E. ); Brennan, T. ); Osborne, M. )

    1988-01-01

    In New York State a survey in 1982-83 discovered fourteen houses with moderately high natural radon levels, and in early 1984 low-cost radon mitigation systems were installed in these houses. The radon reduction techniques included sealing cracks, sealing and sub-slab depressurization, isolating and venting unpaved crawl-spaces, and installing heat-recovery ventilators. These mitigation systems represent some of the earliest systems installed in the United States using low-cost common residential construction materials and methods. In this report, the authors discuss how they returned to these installations, inspected the longevity of the various components of the systems and assessed their long-term effectiveness.

  4. The future through the past: The use of analog sites for design criteria and long-term performance assessment of evapotranspiration landfill covers.

    SciTech Connect

    David Shafer; Julianne Miller; Susan Edwards; Stuart Rawlinson

    2001-10-18

    There is growing support for using evapotranspiration (ET) covers for closure of low-level waste (LLW) and other types of waste disposal sites, particularly in the lower latitude arid regions of the western United States. For the Nevada Test Site (NTS), monolayer ET covers is the baseline technology for closure of LLW and mixed LLW cells. To better predict the long-term performance of monolayer ET covers, as well as to identify design criteria that will potentially improve their performance, the properties of, and processes occurring on, analog sites for ET covers on the NTS are being studied. Four analog sites on the NTS have been selected to predict performance of ET covers over a 1,000-year compliance period. Two are relatively recently disturbed sites (within the last 50 years) and have been selected for the evaluation of processes and changes on ET covers for the early period of post-institutional controls when cover maintenance would be discontinued. Two other sites, late to mid-Holocene in age, are intended as analogs for the end (1,000 years or more) of the compliance period. The late to mid-Holocene surfaces are both abandoned alluvial/colluvial deposits, dated by thermoluminescence analysis. The history of the early post-institutional control analog sites is being evaluated by an archaeologist to help determine when the sites were last disturbed or modified and the mode of disturbance, to help set baseline conditions. Similar to the other ''landforms,'' ET covers will evolve over time because of pedogenic, biotic, and climatic processes. Properties of analog sites that could affect ET water-balance performance will be evaluated to help understand ET cover performance over time. Results of analog site work and resultant modifications to design, monitoring and maintenance of ET covers on the NTS will be compared with results of a similar study being done at Sandia National Laboratories (SNL), where ET cover closures are planned as well. The comparison will

  5. Bridge condition assessment based on long-term strain monitoring

    NASA Astrophysics Data System (ADS)

    Sun, LiMin; Sun, Shouwang

    2011-04-01

    In consideration of the important role that bridges play as transportation infrastructures, their safety, durability and serviceability have always been deeply concerned. Structural Health Monitoring Systems (SHMS) have been installed to many long-span bridges to provide bridge engineers with the information needed in making rational decisions for maintenance. However, SHMS also confronted bridge engineers with the challenge of efficient use of monitoring data. Thus, methodologies which are robust to random disturbance and sensitive to damage become a subject on which many researches in structural condition assessment concentrate. In this study, an innovative probabilistic approach for condition assessment of bridge structures was proposed on the basis of long-term strain monitoring on steel girder of a cable-stayed bridge. First, the methodology of damage detection in the vicinity of monitoring point using strain-based indices was investigated. Then, the composition of strain response of bridge under operational loads was analyzed. Thirdly, the influence of temperature and wind on strains was eliminated and thus strain fluctuation under vehicle loads is obtained. Finally, damage evolution assessment was carried out based on the statistical characteristics of rain-flow cycles derived from the strain fluctuation under vehicle loads. The research conducted indicates that the methodology proposed is qualified for structural condition assessment so far as the following respects are concerned: (a) capability of revealing structural deterioration; (b) immunity to the influence of environmental variation; (c) adaptability to the random characteristic exhibited by long-term monitoring data. Further examination of the applicability of the proposed methodology in aging bridge may provide a more convincing validation.

  6. Summary of Terra and Aqua MODIS Long-Term Performance

    NASA Technical Reports Server (NTRS)

    Xiong, Xiaoxiong (Jack); Wenny, Brian N.; Angal, Amit; Barnes, William; Salomonson, Vincent

    2011-01-01

    Since launch in December 1999, the MODIS ProtoFlight Model (PFM) onboard the Terra spacecraft has successfully operated for more than 11 years. Its Flight Model (FM) onboard the Aqua spacecraft, launched in May 2002, has also successfully operated for over 9 years. MODIS observations are made in 36 spectral bands at three nadir spatial resolutions and are calibrated and characterized regularly by a set of on-board calibrators (OBC). Nearly 40 science products, supporting a variety of land, ocean, and atmospheric applications, are continuously derived from the calibrated reflectances and radiances of each MODIS instrument and widely distributed to the world-wide user community. Following an overview of MODIS instrument operation and calibration activities, this paper provides a summary of both Terra and Aqua MODIS long-term performance. Special considerations that are critical to maintaining MODIS data quality and beneficial for future missions are also discussed.

  7. Long-term performance of motor-operated valves

    SciTech Connect

    Scarbrough, T.G.

    1996-12-01

    The U.S. Nuclear Regulatory Commission (NRC) requires that motor-operated valves (MOVs) important to safety be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions to be performed. Despite these requirements, operating experience and research revealed problems with the performance of MOVs in operating nuclear power plants. In response to the concerns about MOV performance, the NRC issued Generic Letter (GL) 89-10, {open_quotes}Safety-Related Motor-Operated Valve Testing and Surveillance,{close_quotes} and its supplements. Most licensees have completed the aspects of their GL 89-10 programs associated with the review of MOV design bases, verification of MOV switch settings initially, testing of MOVs under design-basis conditions where practicable, and improvement of evaluations of MOV failures and necessary corrective action. Licensees are establishing processes to ensure that the long-term aspects of their MOV programs, such as periodic verification of MOV capability and the trending of MOV problems, are maintained. The NRC staff is developing a generic letter to address periodic verification of MOV design-basis capability.

  8. Long term performance of the Waterloo denitrification barrier

    SciTech Connect

    Robertson, W.D.; Cherry, J.A.

    1997-12-31

    Beginning in 1991 a series of laboratory tests and small scale field trials were initiated to test the performance of an innovative permeable reactive barrier for treatment of nitrate from septic systems. The barrier promotes denitrification by providing an energy source in the form of solid organic carbon mixed into the porous media material. Advantages of the system for nitrate treatment are that the reaction is passive and in situ and it is possible to incorporate sufficient carbon mass in conveniently sized barriers to potentially provide treatment for long periods (decades) without the necessity for maintenance. However, longevity can only be demonstrated by careful long term monitoring of field installations. This paper documents four years of operating history at three small scale field trials; two where the denitrification barrier is installed as a horizontal layer positioned in the unsaturated zone below conventional septic system infiltration beds and one where the barrier is installed as a vertical wall intercepting a septic system plume at a downgradient location. The barriers have successfully attenuated 50-100% of NO{sup -}{sub 3}-N levels of up to 170 mg/L and treatment has remained consistent over the four year period in each case, thus considerable longevity is indicated. Other field trials have demonstrated this technology to be equally effective in treating nitrogen contamination from other sources such as landfill leachate and farm field runoff.

  9. Long-term depot antipsychotics. A risk-benefit assessment.

    PubMed

    Barnes, T R; Curson, D A

    1994-06-01

    The main advantage of depot antipsychotic medication is that it overcomes the problem of covert noncompliance. Patients receiving depot treatment who refuse their injection or fail to receive it for any other reason can be immediately identified and appropriate action taken. In the context of a carefully monitored management programme, depot treatment can have a major impact on compliance and, consequently, the risk of relapse and hospitalisation can be reduced. Another major advantage is that the considerable individual variation in bioavailability and metabolism with oral antipsychotic drugs is markedly reduced with depot treatment. A better correlation between the dose administered and the concentration of medication found in blood or plasma is achieved with depot treatment, and thus, the clinician has greater control over the amount of drug being delivered to the site of activity. A further benefit of depot treatment is the achievement of stable plasma concentrations over long periods, allowing injections to be given every few weeks. However, this also represents a potential disadvantage in that there is a lack of flexibility of administration. Should adverse effects develop, the drug cannot be rapidly withdrawn. Furthermore, adjustment to the optimal dose becomes a long term strategy. The controlled studies of low dose maintenance therapy with depot treatment suggest that it can take months or years for the consequences of dose reduction, in terms of increased risk of relapse, to become manifest. When weighing up the risks and benefits of long term antipsychotic treatment for the individual patient with schizophrenia, the clinician must take into account the nature, severity and frequency of past relapses, and the degree of distress and disability related to any adverse effects. However, the clinical decision to prescribe either a depot or an oral antipsychotic for maintenance treatment will probably rest largely on an assessment of the risk of poor compliance

  10. A modelling study of long term green roof retention performance.

    PubMed

    Stovin, Virginia; Poë, Simon; Berretta, Christian

    2013-12-15

    This paper outlines the development of a conceptual hydrological flux model for the long term continuous simulation of runoff and drought risk for green roof systems. A green roof's retention capacity depends upon its physical configuration, but it is also strongly influenced by local climatic controls, including the rainfall characteristics and the restoration of retention capacity associated with evapotranspiration during dry weather periods. The model includes a function that links evapotranspiration rates to substrate moisture content, and is validated against observed runoff data. The model's application to typical extensive green roof configurations is demonstrated with reference to four UK locations characterised by contrasting climatic regimes, using 30-year rainfall time-series inputs at hourly simulation time steps. It is shown that retention performance is dependent upon local climatic conditions. Volumetric retention ranges from 0.19 (cool, wet climate) to 0.59 (warm, dry climate). Per event retention is also considered, and it is demonstrated that retention performance decreases significantly when high return period events are considered in isolation. For example, in Sheffield the median per-event retention is 1.00 (many small events), but the median retention for events exceeding a 1 in 1 yr return period threshold is only 0.10. The simulation tool also provides useful information about the likelihood of drought periods, for which irrigation may be required. A sensitivity study suggests that green roofs with reduced moisture-holding capacity and/or low evapotranspiration rates will tend to offer reduced levels of retention, whilst high moisture-holding capacity and low evapotranspiration rates offer the strongest drought resistance. PMID:24178313

  11. Quantitative assessment of seismic source performance: Feasibility of small and affordable seismic sources for long term monitoring at the Ketzin CO2 storage site, Germany

    NASA Astrophysics Data System (ADS)

    Sopher, Daniel; Juhlin, Christopher; Huang, Fei; Ivandic, Monika; Lueth, Stefan

    2014-08-01

    We apply a range of quantitative pre-stack analysis techniques to assess the feasibility of using smaller and cheaper seismic sources, than those currently used at the Ketzin CO2 storage site. Results from two smaller land sources are presented alongside those from a larger, more powerful source, typically utilized for seismic acquisition at the Ketzin. The geological target for the study is the Triassic Stuttgart Formation which contains a saline aquifer currently used for CO2 storage. The reservoir lies at a depth of approximately 630 m, equivalent to a travel time of 500 ms along the study profile. The three sources discussed in the study are the Vibsist 3000, Vibsist 500 (using industrial hydraulic driven concrete breaking hammers) and a drop hammer source. Data were collected for the comparison using the three sources in 2011, 2012 and 2013 along a 984 m long line with 24 m receiver spacing and 12 m shot spacing. Initially a quantitative analysis is performed of the noise levels between the 3 surveys. The raw shot gathers are then analyzed quantitatively to investigate the relative energy output, signal to noise ratio, penetration depth, repeatability and frequency content for the different sources. The performance of the sources is also assessed based on stacked seismic sections. Based on the results from this study it appears that both of the smaller sources are capable of producing good images of the target reservoir and can both be considered suitable as lower cost, less invasive sources for use at the Ketzin site or other shallow CO2 storage projects. Finally, the results from the various pre-stack analysis techniques are discussed in terms of how representative they are of the final stacked sections.

  12. Soil quality assessment in long-term direct seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Producers in the Pacific Northwest are adopting direct seed farming to reduce soil erosion, improve soil quality and increase water infiltration. Some direct seed producers are concerned with reaching the yield and profit potential expected with long-term direct seed, and this may be due to soil st...

  13. Technology base studies of long-term MCFC performance

    SciTech Connect

    Selman, J.R.; Yazici, M.S.

    1996-12-31

    This project aims to identify the long-term endurance problems of the MCFC by investigating corrosion of stainless steel (310, 316L). This presentation focuses on results from SEM and cross-section analysis. Significant differences between immersed and film-wetted electrodes are summarized. Results suggest that pre-oxidation can be a solution to obtaining a compact oxide layer. Adding Al to alloy leads to a very stable oxide layer, but increases resistivity. Alloy behavior must be investigated under continuously polarized conditions. 4 figs.

  14. Subjective Memory Ability and Long-Term Forgetting in Patients Referred for Neuropsychological Assessment

    PubMed Central

    van der Werf, Sieberen P.; Geurts, Sofie; de Werd, Maartje M. E.

    2016-01-01

    It has been suggested that the memory complaints of patients who are not impaired on formal memory tests may reflect accelerated forgetting. We examined this hypothesis by comparing the 1-week delayed recall and recognition test performance of outpatients who were referred for neuropsychological assessment and who had normal memory performance during standard memory assessment with that of a non-patient control group. Both groups performed equally in verbal learning and delayed recall. However, after 1 week, the patients performed worse than controls on both recall and recognition tests. Although subjective memory ability predicted short-term memory function in patients, it did not predict long-term delayed forgetting rates in either the patients or controls. Thus, long-term delayed recall and recognition intervals provided no additional value to explain poor subjective memory ability in the absence of objective memory deficits. PMID:27199838

  15. Performance assessment of a commonly used "accumulation and wash-off" model from long-term continuous road runoff turbidity measurements.

    PubMed

    Sage, Jérémie; Bonhomme, Céline; Al Ali, Saja; Gromaire, Marie-Christine

    2015-07-01

    The suitability of a commonly used accumulation and wash-off model for continuous modelling of urban runoff contamination was evaluated based on 11-month turbidity and flow-rate records from an urban street. Calibration and uncertainty analysis were performed using a Markov Chain Monte-Carlo sampling method for both suspended solids loads (discharge rates) and concentration modelling. Selected models failed at replicating suspended solids concentration over the complete monitoring period. The studied dataset indeed suggests that the accumulation process is rather unpredictable and cannot be satisfactorily represented with usual accumulation models unless short periods are considered. Regarding suspended solid loads modelling, noticeably better performance was achieved, but similar results could as well be obtained with much simpler constant concentration models. Unless providing very accurate estimates of concentrations in runoff, accounting for their temporal variability during rain events may therefore not always be necessary for pollutant loads modelling, as loads are in fact mostly explained by runoff volumes. PMID:25909578

  16. Corrosion of Spent Nuclear Fuel: The Long-Term Assessment

    SciTech Connect

    Rodney C. Ewing

    2004-10-07

    Spent nuclear fuel, essentially U{sub 2}, accounts for over 95% of the total radioactivity of all of the radioactive wastes in the United States that require disposal, disposition or remediation. The UO{sub 2} in SNF is not stable under oxiding conditions and may also be altered under reducing conditions. The alteration of SNF results in the formation of new uranium phases that can cause the release or retardation of actinide and fission product radionuclides. Over the long term, and depending on the extent to which the secondary uranium phases incorporate fission products and actinides, these alteration phases become the near-field source term.

  17. Exercise Performance in Patients with D-Loop Transposition of the Great Arteries After Arterial Switch Operation: Long-Term Outcomes and Longitudinal Assessment.

    PubMed

    Kuebler, Joseph D; Chen, Ming-Hui; Alexander, Mark E; Rhodes, Jonathan

    2016-02-01

    The first patients to undergo a successful arterial switch operation (ASO) for d-transposition of the great arteries (D-TGA) are now entering their fourth decade of life. Past studies of ASO survivors' exercise function have yielded conflicting results. We therefore undertook this study to describe the current function of ASO survivors, to identify factors related to inferior exercise performance and to determine whether their exercise function tends to deteriorate over time. A retrospective cohort study was designed examining all patients with D-TGA after the ASO who underwent comprehensive cardiopulmonary exercise testing (CPET). Patients with palliative surgery prior to ASO, ventricular hypoplasia or severe valvar dysfunction were excluded from the study. Data from CPETs in which the peak respiratory exchange ratio was <1.09 were also excluded. We identified 113 patients who met entry criteria and had 186 CPX at our institution between 1/2002 and 1/2013; 41 patients had at least 2 qualifying CPX. Mean age at the time of the initial test was 17 ± 1 year. Peak oxygen consumption (VO2) averaged 84 ± 2 % predicted. Peak VO2 was lower among patients with repaired ventricular septal defects (82 ± 4 vs. 86 ± 3 % predicted; p < 0.05) and among patients with ≥ moderate right-sided obstructive lesions (77 ± 5 vs. 87 ± 3 % predicted; p < 0.05). Surgery prior to 1991 was also associated with a lower peak VO2 (81 ± 3 vs. 87 ± 3 % predicted; p < 0.01). The mean % predicted peak heart rate was 92 ± 1 %, with no significant difference between any of the subgroups. Non-diagnostic exercise-induced STT changes developed in 10 patients (12 studies). In the subgroup with at least 2 exercise tests, the annual decline in % predicted peak VO2 was quite slow (-0.3 % points/year; p < 0.01 vs. expected normal age-related decline). The exercise capacity of ASO survivors is well preserved and is only mildly reduced compared to normal subjects. Moreover, there is only a slight

  18. Assessment of Long-Term Research Needs for Coal-Liquefaction Technologies

    SciTech Connect

    Penner, S.S.

    1980-03-01

    The Fossil Energy Research Working Group (FERWG), at the request of J.M. Deutch (Under Secretary of DOE), E. Frieman (Director, Office of Energy Research) and G. Fumich, Jr. (Assistant Secretary for Fossil Fuels), has studied and reviewed currently funded coal-liquefaction technologies. These studies were performed in order to provide an independent assessment of critical research areas that affect the long-term development of coal-liquefaction technologies. This report summarizes the findings and research recommendations of FERWG.

  19. Assessment of Long-Term Research Needs for Shale-Oil Recovery (FERWG-III)

    SciTech Connect

    Penner, S.S.

    1981-03-01

    The Fossil Energy Research Working Group (FERWG), at the request of E. Frieman (Director, Office of Energy Research) and G. Fumich, Jr. (Assistant Secretary for Fossil Fuels), has reviewed and evaluated the U.S. programs on shale-oil recovery. These studies were performed in order to provide an independent assessment of critical research areas that affect the long-term prospects for shale-oil availability. This report summarizes the findings and research recommendations of FERWG.

  20. Assessment of long-term gas sampling design at two commercial manure-belt layer barns.

    PubMed

    Chai, Li-Long; Ni, Ji-Qin; Chen, Yan; Diehl, Claude A; Heber, Albert J; Lim, Teng T

    2010-06-01

    Understanding temporal and spatial variations of aerial pollutant concentrations is important for designing air quality monitoring systems. In long-term and continuous air quality monitoring in large livestock and poultry barns, these systems usually use location-shared analyzers and sensors and can only sample air at limited number of locations. To assess the validity of the gas sampling design at a commercial layer farm, a new methodology was developed to map pollutant gas concentrations using portable sensors under steady-state or quasi-steady-state barn conditions. Three assessment tests were conducted from December 2008 to February 2009 in two manure-belt layer barns. Each barn was 140.2 m long and 19.5 m wide and had 250,000 birds. Each test included four measurements of ammonia and carbon dioxide concentrations at 20 locations that covered all operating fans, including six of the fans used in the long-term sampling that represented three zones along the lengths of the barns, to generate data for complete-barn monitoring. To simulate the long-term monitoring, gas concentrations from the six long-term sampling locations were extracted from the 20 assessment locations. Statistical analyses were performed to test the variances (F-test) and sample means (t test) between the 6- and 20-sample data. The study clearly demonstrated ammonia and carbon dioxide concentration gradients that were characterized by increasing concentrations from the west to east ends of the barns following the under-cage manure-belt travel direction. Mean concentrations increased from 7.1 to 47.7 parts per million (ppm) for ammonia and from 2303 to 3454 ppm for carbon dioxide from the west to east of the barns. Variations of mean gas concentrations were much less apparent between the south and north sides of the barns, because they were 21.2 and 20.9 ppm for ammonia and 2979 and 2951 ppm for carbon dioxide, respectively. The null hypotheses that the variances and means between the 6- and 20

  1. Long-term Radiographic Assessment of Cemented Polyethylene Acetabular Cups

    PubMed Central

    Isaac, Graham; Porter, Neil; Fisher, John; Older, John

    2008-01-01

    In vitro studies demonstrating excessive wear in polyethylene cups sterilized using gamma irradiation and stored in air led to the abandonment of this sterilization technique. We evaluated the clinical wear performance of a metal femoral component on a polyethylene cup in a hip prosthesis from a selected subset of implants in a group of patients followed for at least 20 years and assessed the time dependency of variation in penetration rates. We measured penetration in 33 polyethylene cups in 25 patients who had a Charnley low-friction arthroplasty between 1982 and 1984. All patients had Charnley Ogee® cups implanted for more than 20 years and sterilized using the gamma irradiation in air technique. If degradation occurred over time in vivo, it was not reflected by an increased penetration rate with increasing time in vivo; even after 20 years of implantation, the degree of wear remained low. This suggests gamma irradiation affects wear on ultra-high-molecular-weight polyethylene by reducing wear secondary to the crosslinking, by increasing wear as shown through in vitro studies of heavily oxidized samples, or by oxidation resulting from prolonged shelf life. The effect of progressive oxidation in vivo does not appear to affect wear in vivo. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18196419

  2. Long term assessment of intralipotherapy in Madelung's disease.

    PubMed

    Scevola, Silvia; Nicoletti, Giovanni; Neri, Antonino; Faga, Angela

    2014-01-01

    Madelung's disease is characterised by multiple symmetric abnormal fat masses in the head, neck and upper limbs. Surgical excision or liposuction is the only realistic available option, although palliative in nature. The serial intralipotherapy with phosphatidylcholine/deoxycholate has been proposed as a non-invasive treatment of Madelung's disease. The authors used serial intralipotherapy with phosphatidylcholine/deoxycholate in two patients affected by Madelung's disease. Three injections per lesion per patient were performed with 1 month's interval. Pre- and 6 months' post-treatment dimensions were assessed with ultrasound scan and patients were observed along a 5 years' clinical follow-up. A 42.5% average size reduction was reported in all treated lesions. About 33% recurrence rate was observed in the 5 years' follow-up. We confirm the efficacy of intralipotherapy in the non-invasive palliative treatment of Madelung's disease, as a valid option to reduce the volume and limit the growth of the pathological adipose masses. PMID:25593434

  3. Long term assessment of intralipotherapy in Madelung's disease

    PubMed Central

    Scevola, Silvia; Nicoletti, Giovanni; Neri, Antonino; Faga, Angela

    2014-01-01

    Madelung's disease is characterised by multiple symmetric abnormal fat masses in the head, neck and upper limbs. Surgical excision or liposuction is the only realistic available option, although palliative in nature. The serial intralipotherapy with phosphatidylcholine/deoxycholate has been proposed as a non-invasive treatment of Madelung's disease. The authors used serial intralipotherapy with phosphatidylcholine/deoxycholate in two patients affected by Madelung's disease. Three injections per lesion per patient were performed with 1 month's interval. Pre- and 6 months’ post-treatment dimensions were assessed with ultrasound scan and patients were observed along a 5 years’ clinical follow-up. A 42.5% average size reduction was reported in all treated lesions. About 33% recurrence rate was observed in the 5 years’ follow-up. We confirm the efficacy of intralipotherapy in the non-invasive palliative treatment of Madelung's disease, as a valid option to reduce the volume and limit the growth of the pathological adipose masses. PMID:25593434

  4. Long-Term and Within-Day Variability of Working Memory Performance and EEG in Individuals

    PubMed Central

    Gevins, Alan; McEvoy, Linda K.; Smith, Michael E.; Chan, Cynthia S.; Sam-Vargas, Lita; Baum, Cliff; Ilan, Aaron B.

    2011-01-01

    Objective Assess individual-subject long-term and within-day variability of a combined behavioral and EEG test of working memory. Methods EEGs were recorded from 16 adults performing n-back working memory tasks, with 10 tested in morning and afternoon sessions over several years. Participants were also tested after ingesting non-prescription medications or recreational substances. Performance and EEG measures were analyzed to derive an Overall score and three constituent sub-scores characterizing changes in performance, cortical activation, and alertness from each individual’s baseline. Long-term and within-day variability were determined for each score; medication effects were assessed by reference to each individual’s normal day-to-day variability. Results Over the several year period, the mean Overall score and sub-scores were approximately zero with standard deviations less than one. Overall scores were lower and their variability higher in afternoon relative to morning sessions. At the group level, alcohol, diphenhydramine and marijuana produced significant effects, but there were large individual differences. Conclusions Objective working memory measures incorporating performance and EEG are stable over time and sensitive at the level of individual subjects to interventions that affect neurocognitive function. Significance With further research these measures may be suitable for use in individualized medical care by providing a sensitive assessment of incipient illness and response to treatment. PMID:22154302

  5. Hippocampal CA1 Kindling but Not Long-Term Potentiation Disrupts Spatial Memory Performance

    ERIC Educational Resources Information Center

    Leung, L. Stan; Shen, Bixia

    2006-01-01

    Long-term synaptic enhancement in the hippocampus has been suggested to cause deficits in spatial performance. Synaptic enhancement has been reported after hippocampal kindling that induced repeated electrographic seizures or afterdischarges (ADs) and after long-term potentiation (LTP) defined as synaptic enhancement without ADs. We studied…

  6. LONG-TERM PERFORMANCE OF PERMEABLE REACTIVE BARRIERS: LESSONS LEARNED

    EPA Science Inventory

    This presentation will provide an overview of research efforts at EPA on the application, monitoring, and performance of Permeable Reactive Barriers (PRBs) for groundwater restoration. Over the past 10 years, research projects conducted by research staff at EPA's National Risk M...

  7. Long term experience and performance of COMPASS RICH-1

    NASA Astrophysics Data System (ADS)

    Tessarotto, F.; Abbon, P.; Alexeev, M.; Birsa, R.; Bordalo, P.; Bradamante, F.; Bressan, A.; Büchele, M.; Chiosso, M.; Ciliberti, P.; Dafni, T.; Dalla Torre, S.; Dasgupta, S.; Delagnes, E.; Denisov, O.; Duic, V.; Ferrero, A.; Finger, M.; Finger, M., Jr.; Fischer, H.; Franco, C.; Gerassimov, S.; Gobbo, B.; Gregori, M.; Herrmann, F.; Ketzer, B.; Königsmann, K.; Konorov, I.; Kunne, F.; Levorato, S.; Maggiora, A.; Makke, N.; Martin, A.; Menon, G.; Neyret, D.; Novakova, K.; Panzieri, D.; Paul, S.; Pereira, F. A.; Polak, J.; Rocco, E.; Santos, C. A.; Sbrizzai, G.; Schiavon, P.; Schopferer, S.; Slunecka, M.; Sozzi, F.; Steiger, L.; Sulc, M.; Takekawa, S.

    2014-09-01

    COMPASS RICH-1 is a large size gaseous Imaging Cherenkov Detector providing hadron identification in the range from 3 to 55 GeV/c, in the wide acceptance spectrometer of the COMPASS Experiment at CERN SPS. It uses a 3 m long C4F10 radiator, a 21 m2 large VUV mirror surface and two kinds of photon detectors: MAPMTs and MWPCs with CsI photocathodes, covering a total of 5.5 m2. It is in operation since 2002 and its performance increased thanks to progressive optimization and to a major upgrade of its photon detection system, implemented in 2006; a new upgrade is foreseen for 2016, with the use of MPGD-based photon detectors. The main characteristics of COMPASS RICH-1 components are described and the most critical aspects related to the C4F10 radiator gas system, to the mirrors and their alignment, as well as the performance of the photon detectors are presented and discussed. The response of the MWPCs and the observed evolution of the effective quantum efficiency of the CsI photocathodes is analyzed. The properties and performance of the MAPMTs with individual fused lens telescopes are presented together with the readout characteristics. The PID performance of COMPASS RICH-1 is discussed and the future upgrade program is mentioned.

  8. Long term performance of wearable transducer for motion energy harvesting

    NASA Astrophysics Data System (ADS)

    McGarry, Scott A.; Behrens, Sam

    2010-04-01

    Personal electronic devices such as cell phones, GPS and MP3 players have traditionally depended on battery energy storage technologies for operation. By harvesting energy from a person's motion, these devices may achieve greater run times without increasing the mass or volume of the electronic device. Through the use of a flexible piezoelectric transducer such as poly-vinylidene fluoride (PVDF), and integrating it into a person's clothing, it becomes a 'wearable transducer'. As the PVDF transducer is strained during the person's routine activities, it produces an electrical charge which can then be harvested to power personal electronic devices. Existing wearable transducers have shown great promise for personal motion energy harvesting applications. However, they are presently physically bulky and not ergonomic for the wearer. In addition, there is limited information on the energy harvesting performance for wearable transducers, especially under realistic conditions and for extended cyclic force operations - as would be experienced when worn. In this paper, we present experimental results for a wearable PVDF transducer using a person's measured walking force profile, which is then cycled for a prolonged period of time using an experimental apparatus. Experimental results indicate that after an initial drop in performance, the transducer energy harvesting performance does not substantially deteriorate over time, as less than 10% degradation was observed. Longevity testing is still continuing at CSIRO.

  9. Field performance of transgenic citrus trees: Assessment of the long-term expression of uidA and nptII transgenes and its impact on relevant agronomic and phenotypic characteristics

    PubMed Central

    2012-01-01

    Background The future of genetic transformation as a tool for the improvement of fruit trees depends on the development of proper systems for the assessment of unintended effects in field-grown GM lines. In this study, we used eight transgenic lines of two different citrus types (sweet orange and citrange) transformed with the marker genes β-glucuronidase (uidA) and neomycin phosphotransferase II (nptII) as model systems to study for the first time in citrus the long-term stability of transgene expression and whether transgene-derived pleiotropic effects occur with regard to the morphology, development and fruit quality of orchard-grown GM citrus trees. Results The stability of the integration and expression of the transgenes was confirmed in 7-year-old, orchard-grown transgenic lines by Southern blot analysis and enzymatic assays (GUS and ELISA NPTII), respectively. Little seasonal variation was detected in the expression levels between plants of the same transgenic line in different organs and over the 3 years of analysis, confirming the absence of rearrangements and/or silencing of the transgenes after transferring the plants to field conditions. Comparisons between the GM citrus lines with their non-GM counterparts across the study years showed that the expression of these transgenes did not cause alterations of the main phenotypic and agronomic plant and fruit characteristics. However, when comparisons were performed between diploid and tetraploid transgenic citrange trees and/or between juvenile and mature transgenic sweet orange trees, significant and consistent differences were detected, indicating that factors other than their transgenic nature induced a much higher phenotypic variability. Conclusions Our results indicate that transgene expression in GM citrus remains stable during long-term agricultural cultivation, without causing unexpected effects on crop characteristics. This study also shows that the transgenic citrus trees expressing the

  10. The impact of impurities on long-term PEMFC performance

    SciTech Connect

    Garzon, Fernando H; Lopes, Thiago; Rockward, Tommy; Mukundan, Rangachary; Sansinena, Jose - Maria; Kienitz, Brian

    2009-06-23

    Electrochemical experimentation and modeling indicates that impurities degrade fuel cell performance by a variety of mechanisms. Electrokinetics may be inhibited by catalytic site poisoning from sulfur compounds and CO and by decreased local proton activity and mobility caused by the presence of foreign salt cations or ammonia. Cation impurity profiles vary with current density, valence and may change local conductivity and water concentrations in the ionomer. Nitrogen oxides and ammonia species may be electrochemically active under fuel cell operating conditions. The primary impurity removal mechanisms are electrooxidation and water fluxes through the fuel cell.

  11. Long-Term Performance of Uranium Tailings Disposal Cells - 13340

    SciTech Connect

    Bostick, Kent; Daniel, Anamary; Pill, Ken; Tachiev, Georgio; Noosai, Nantaporn; Villamizar, Viviana

    2013-07-01

    Recently, there has been interest in the performance and evolution of Uranium Mill Tailings Remedial Action (UMTRA) Project disposal cell covers because some sites are not compliant with groundwater standards. Field observations of UMTRA disposal cells indicate that rock covers tend to become vegetated and that saturated conductivities in the upper portion of radon barriers may increase due to freeze/thaw cycles and biointrusion. This paper describes the results of modeling that addresses whether these potential changes and transient drainage of moisture in the tailings affect overall performance of the disposal cells. A numerical unsaturated/saturated 3-dimensional flow model was used to simulate whether increases in saturated conductivities in radon barriers with rock covers affect the overall performance of the disposal cells using field data from the Shiprock, NM, UMTRA site. A unique modeling approach allowed simulation with daily climatic conditions to determine changes in moisture and moisture flux from the disposal cell. Modeling results indicated that increases in the saturated conductivity at the top of radon barrier do not influence flux from the tailings with time because the tailings behave similar hydraulically to the radon barrier. The presence of a thin layer of low conductivity material anywhere in the cover or tailings restricts flux in the worst case to the saturated conductivity of that material. Where materials are unsaturated at depth within the radon barrier of tailings slimes, conductivities are typically less than 10{sup -8} centimeters per second. If the low conductivity layer is deep within the disposal cell, its saturated properties are less likely to change with time. The significance of this modeling is that operation and maintenance of the disposal cells can be minimized if they are allowed to progress to a natural condition with some vegetation and soil genesis. Because the covers and underlying tailings have a very low saturated

  12. Long Term Trend Analysis and Assessment of Water Quality in the Penchala River, Malaysia

    NASA Astrophysics Data System (ADS)

    Chow, M. F.; Haris, H. B.; Mohd Sidek, L. B.

    2014-12-01

    Rapid urban expansion produces negative impacts on the natural environment, especially river water quality. Studies assessing long term changes of water quality have been recognized as a key tool for understanding ongoing processes in watersheds and for providing an essential background for evaluation of rapid changes within industrialized and populated urban areas. Unfortunately, only limited studies are available for developing countries such as Malaysia. Thus, a long term study was conducted to evaluate water quality trends at Pencala river basin that has undergone extensive land use changes related to industrial, agricultural and urban activities. Fifteen physical and chemical variables were analysed in river water samples collected every month over a period of 13 years, between 1997 and 2009. The trend study was performed using the Mann-Kendall Seasonal test and the Sen's Slope estimator. Results revealed that most water quality parameters showed a downward trend for yearly average concentration. The water quality index (WQI) for Pencala River was improved from Class V to Class IV, according to National Water Quality Standards for Malaysia. BOD, COD, NH3-N and SS show trends toward decreasing concentrations over time. The improvements seen in water quality appear to be the result of improved wastewater treatment and other water quality improvement efforts achieved through government initiative. Continued long-term and high frequency monitoring is necessary to establish plans and policies for effective water resources management.

  13. Risk Assessment and Control through Countermeasure System Iplementation for Long-term Crew Exposure to Microgravity

    NASA Technical Reports Server (NTRS)

    Gernand, Jeremy M.

    2004-01-01

    Experience with the International Space Station (ISS) program demonstrates the degree to which engineering design and operational solutions must protect crewmembers from health risks due to long-term exposure to the microgravity environment. Risks to safety and health due to degradation in the microgravity environment include crew inability to complete emergency or nominal activities, increased risk of injury, and inability to complete safe return to the ground due to reduced strength or embrittled bones. These risks without controls slowly increase in probability for the length of the mission and become more significant for increasing mission durations. Countermeasures to microgravity include hardware systems that place a crewmember s body under elevated stress to produce an effect similar to daily exposure to gravity. The ISS countermeasure system is predominately composed of customized exercise machines. Historical treatment of microgravity countermeasure systems as medical research experiments unintentionally reduced the foreseen importance and therefore the capability of the systems to function in a long-term operational role. Long-term hazardous effects and steadily increasing operational risks due to non-functional countermeasure equipment require a more rigorous design approach and incorporation of redundancy into seemingly non- mission-critical hardware systems. Variations in the rate of health degradation and responsiveness to countermeasures among the crew population drastically increase the challenge for design requirements development and verification of the appropriate risk control strategy. The long-term nature of the hazards and severe limits on logistical re-supply mass, volume and frequency complicates assessment of hardware availability and verification of an adequate maintenance and sparing plan. Design achievement of medically defined performance requirements by microgravity countermeasure systems and incorporation of adequate failure tolerance

  14. Modelling Tradescantia fluminensis to assess long term survival

    PubMed Central

    Molloy, Sue M.; Ponder-Sutton, Agate; Plank, Michael J.; Lamoureaux, Shona L.; Bourdôt, Graeme W.; Kelly, Dave

    2015-01-01

    We present a simple Poisson process model for the growth of Tradescantia fluminensis, an invasive plant species that inhibits the regeneration of native forest remnants in New Zealand. The model was parameterised with data derived from field experiments in New Zealand and then verified with independent data. The model gave good predictions which showed that its underlying assumptions are sound. However, this simple model had less predictive power for outputs based on variance suggesting that some assumptions were lacking. Therefore, we extended the model to include higher variability between plants thereby improving its predictions. This high variance model suggests that control measures that promote node death at the base of the plant or restrict the main stem growth rate will be more effective than those that reduce the number of branching events. The extended model forms a good basis for assessing the efficacy of various forms of control of this weed, including the recently-released leaf-feeding tradescantia leaf beetle (Neolema ogloblini). PMID:26082865

  15. Assessment of Countermeasure Efficacy for Long-Term Space Missions

    NASA Technical Reports Server (NTRS)

    Feiveson, Alan H.; Paloski, William H. (Technical Monitor)

    2000-01-01

    One of the main functions of the upcoming International Space Station (ISS) will be to provide a venue for testing proposed countermeasures for their ability to protect humans from the debilitating effects of longterm space flight. However, several limiting factors preclude an evaluation process similar to that used in clinical trials which traditionally are implemented with large sample sizes of subjects, including control groups, and with blind or double-blind application of treatments according to factorial or other balanced experimental designs. In particular, only very limited numbers of human subjects will be available for actual field testing in the ISS With no more than 125 subjects planned to fly on all ISS missions over 10 years, it is not possible to test extensive combinations of some 15-20 proposed countermeasures. Furthermore because of safety concerns and operational considerations, it is unlikely that anything other than the current best guess at the most effective countermeasure package will ever be used on ISS. In particular, control or placebos will not be allowed. In view of these limitations, historical data and groundbased or animal studies will have to be used to compensate for small sample sizes and lack of controls in the field. As a result, statistical analysis methodology will have to be developed which allows for the integration of these disparate data types into a meaningful evaluation process. The process must be sequential, providing objective rules for deciding through time whether to reject or modify an ineffective countermeasure, or whether to certify one as effective. Additional output should include performance characteristics for all relevant physiological systems, including uncertainty analyses and estimates of accept/reject decision error rates.

  16. Study of advanced techniques for determining the long term performance of components

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The application of existing and new technology to the problem of determining the long-term performance capability of liquid rocket propulsion feed systems is discussed. The long term performance of metal to metal valve seats in a liquid propellant fuel system is stressed. The approaches taken in conducting the analysis are: (1) advancing the technology of characterizing components through the development of new or more sensitive techniques and (2) improving the understanding of the physical of degradation.

  17. Long-term Results of an Analytical Assessment of Student Compounded Preparations

    PubMed Central

    Roark, Angie M.; Anksorus, Heidi N.

    2014-01-01

    Objective. To investigate the long-term (ie, 6-year) impact of a required remake vs an optional remake on student performance in a compounding laboratory course in which students’ compounded preparations were analyzed. Methods. The analysis data for several preparations made by students were compared for differences in the analyzed content of the active pharmaceutical ingredient (API) and the number of students who successfully compounded the preparation on the first attempt. Results. There was a consistent statistical difference in the API amount or concentration in 4 of the preparations (diphenhydramine, ketoprofen, metoprolol, and progesterone) in each optional remake year compared to the required remake year. As the analysis requirement was continued, the outcome for each preparation approached and/or attained the expected API result. Two preparations required more than 1 year to demonstrate a statistical difference. Conclusion. The analytical assessment resulted in a consistent, long-term improvement in student performance during the 5-year period after the optional remake policy was instituted. Our assumption is that investment in such an assessment would result in a similar benefits at other colleges and schools of pharmacy. PMID:26056402

  18. Long term performance of membranes in an anaerobic membrane bioreactor treating municipal wastewater.

    PubMed

    Dong, Qirong; Parker, Wayne; Dagnew, Martha

    2016-02-01

    The long term impact of SRT (100-40 days) and recovery cleaning on membrane performance of an AnMBR treating authentic municipal wastewater in a large pilot plant was assessed. Successful operation of the pilot plant at a flux of 17 LMH was maintained for a period of 536 days during which the longest period of operation without recovery cleaning or membrane replacement was 178 days. Lower SRT (40 days) reduced the fouling propensity of the mixed liquor in terms of TSS concentration and the dewaterability indicators including colloidal COD (cCOD) concentration and capillary suction time (CST). Critical fluxes ranged from 21 to 23 LMH to 25-27 LMH for SRTs of 70 and 40 days respectively and this was consistent with the reduced concentrations of TSS and improved dewaterability under the latter conditions. Recovery cleaning was found to result in substantial reduction of resistance as indicated by both pilot plant operation and clean water flux tests. The long-term fouling rate was observed to be higher with cleaned membranes as compared to virgin membranes. The lower membrane fouling with virgin membranes suggested that accumulation of foulants, which were resistant to cleaning, caused the higher fouling rates for the cleaned membranes. PMID:26363327

  19. Assessment of long-term vicarious calibration efforts of MERIS on land product quality

    NASA Astrophysics Data System (ADS)

    Schaepman, Michael E.; Zurita-Milla, Raul; Kneubuehler, Mathias; Clevers, Jan; Delwart, Steven

    2004-11-01

    Since the launch of MERIS on ENVISAT long term activities using vicarious calibration approaches are set in place to monitor potential drifts in calibration in the radiance products of MERIS. We are using a stable, well monitored reference calibration site (Railroad Valley, Nevada, USA) to derive calibration uncertainties of MERIS over time. We are using interpolation of uncertainties to derive a second set of uncertainties for a national data validation in the Netherlands. A satellite image derived land use map of the Netherlands (LGN4) is used to determine the largest homogeneous land use classes using a standard purity index (SPI). Potential adjacency effects are minimized using moving window filters on the pixels of the aggregated map. Multiple error propagation is being used to assess the impact of calibration accuracy on land use classification. A classification in 9 land use classes is finally performed on MERIS FR images of the Netherlands using image based spectral unmixing and matched filtering with endmembers derived from the LGN. We conclude that the classification performance may significantly be increased, when taking into account long-term vicarious calibration results.

  20. Assessment Of Errors In Long-Term Mass Balance Records From Alaska, USA

    NASA Astrophysics Data System (ADS)

    March, R. S.; van Beusekom, A. E.; O'Neel, S.

    2009-12-01

    The USGS maintains a long-term glacier mass balance monitoring program at Gulkana and Wolverine glaciers in Alaska. The records produced by this program are a major component of the world’s mountain glacier balance inventory due to the scarcity of such long-term measurements. Recent data that show rapid glacier volume loss in Alaska further emphasize the importance of these records. An integral part of the long-term mass balance program is repeated assessment of the validity of the methods because bias errors in mass balance data are cumulative. Long-term glacier mass balance records in Alaska have previously been shown to be in good agreement with geodetically determined volume changes despite a minimal network of mass balance stakes. Because the rates of negative mass balance and change in glacier geometry have recently increased, this work reassess whether or not the existing stake networks and method of determining glacier-average balance are still working adequately.

  1. Long-Term Memory Performance in Adult ADHD: A Meta-Analysis.

    PubMed

    Skodzik, Timo; Holling, Heinz; Pedersen, Anya

    2013-11-14

    Objective: Memory problems are a frequently reported symptom in adult ADHD, and it is well-documented that adults with ADHD perform poorly on long-term memory tests. However, the cause of this effect is still controversial. The present meta-analysis examined underlying mechanisms that may lead to long-term memory impairments in adult ADHD. Method: We performed separate meta-analyses of measures of memory acquisition and long-term memory using both verbal and visual memory tests. In addition, the influence of potential moderator variables was examined. Results: Adults with ADHD performed significantly worse than controls on verbal but not on visual long-term memory and memory acquisition subtests. The long-term memory deficit was strongly statistically related to the memory acquisition deficit. In contrast, no retrieval problems were observable. Conclusion: Our results suggest that memory deficits in adult ADHD reflect a learning deficit induced at the stage of encoding. Implications for clinical and research settings are presented. (J. of Att. Dis. XXXX; XX(X) XX-XX). PMID:24232170

  2. High Temperature Steam Electrolysis: Demonstration of Improved Long-Term Performance

    SciTech Connect

    J. E. O'Brien; X. Zhang; R. C. O'Brien; G. Tao

    2011-11-01

    Long-term performance is an ongoing issue for hydrogen production based on high-temperature steam electrolysis (HTSE). For commercial deployment, solid-oxide electrolysis stacks must achieve high performance with long-term degradation rates of {approx}0.5%/1000 hours or lower. Significant progress has been achieved toward this goal over the past few years. This paper will provide details of progress achieved under the Idaho National Laboratory high temperature electrolysis research program. Recent long-term stack tests have achieved high initial performance with degradation rates less than 5%/khr. These tests utilize internally manifolded stacks with electrode-supported cells. The cell material sets are optimized for the electrolysis mode of operation. Details of the cells and stacks will be provided along with details of the test apparatus, procedures, and results.

  3. Assessment of the long-term risks of inadvertent human intrusion

    SciTech Connect

    Wuschke, D.M. )

    1993-01-01

    Canada has conducted an extensive research program on the safe disposal of nuclear fuel wastes. The program has focused on the concept of disposal of spent fuel in durable containers in an engineered facility, or vault, 500 to 1000 m deep in intrusive igneous rock in the Canadian Shield. An essential goal of this program has been to develop and demonstrate a methodology to evaluate the performance of the facility against safety criteria established by Canada's regulatory agency, the Atomic Energy Control Board (AECB). These criteria are expressed in terms of risk, where risk is defined as the sum over all significant scenarios of the product of the probability of the scenario, the magnitude of the resultant dose, and the probability of a health effect per unit dose. This paper describes the methodology developed to assess the long-term risk from inadvertent human intrusion into such a facility and the results of its application to a conceptual design of such a facility.

  4. Development of long-term performance models for radioactive waste forms

    SciTech Connect

    Bacon, Diana H.; Pierce, Eric M.

    2011-03-22

    The long-term performance of solid radioactive waste is measured by the release rate of radionuclides into the environment, which depends on corrosion or weathering rates of the solid waste form. The reactions involved depend on the characteristics of the solid matrix containing the radioactive waste, the radionuclides of interest, and their interaction with surrounding geologic materials. This chapter describes thermo-hydro-mechanical and reactive transport models related to the long-term performance of solid radioactive waste forms, including metal, ceramic, glass, steam reformer and cement. Future trends involving Monte-Carlo simulations and coupled/multi-scale process modeling are also discussed.

  5. PERMEABLE REACTIVE BARRIER PERFORMANCE MONITORING: LONG-TERM TRENDS IN GEOCHEMICAL PARAMETERS AT TWO SITES

    EPA Science Inventory

    A major goal of research on the long-term performance of subsurface reactive barriers is to identify standard ground water monitoring parameters that may be useful indicators of declining performance or impending system failure. Results are presented from ground water monitoring ...

  6. PERMEABLE REACTIVE BARRIER PERFORMANCE MONITORING: LONG-TERM TRENDS IN GEOCHEMICAL PARAMETERS AT TWO SITES

    EPA Science Inventory

    A major goal of research on the long-term performance of subsurface reactive barriers is to identify standard ground-water monitoring parameters that may be useful indicators of declining performance or impending system failure. Results are presented from studies conducted over ...

  7. Long-term performance of landfill covers - results of lysimeter test fields in Bavaria (Germany).

    PubMed

    Henken-Mellies, Wolf-Ulrich; Schweizer, Andreas

    2011-01-01

    A comprehensive study was conducted to examine the performance and possible changes in the effectiveness of landfill surface covers. Three different profiles of mineral landfill caps were examined. The results of precipitation and flow measurements show distinct seasonal differences which are typical for middle-European climatic conditions. In the case of the simple landfill cap design consisting of a thick layer of loamy sand, approximately 100-200 L m(-2) of annual seepage into the landfill body occurs during winter season. The three-layer systems of the two other test fields performed much better. Most of the water which percolated through the top soil profile drained sideways in the drainage layer. Only 1-3% of precipitation percolated through the sealing layer. The long-term effectiveness of the mineral sealing layer depended on the ability of the top soil layer to protect it from critical loss of soil water/critical increase of suction. In dry summers there was even a loss in soil water content at the base of the 2.0 m thick soil cover. The results of this study demonstrate the importance of the long-term aspect when assessing the effectiveness of landfill covers: The hydraulic conductivity at the time of construction gives only an initial (minimum) value. The hydraulic conductivity of the compacted clay layer or of the geosynthetic clay liner may increase substantially, if there is no long-lasting protection against desiccation (by a thick soil cover or by a geomembrane). This has to be taken into account in landfill cover design. PMID:20937619

  8. Long-term memory performance after surgical treatment of unilateral temporal lobe epilepsy (TLE).

    PubMed

    Jutila, Leena; Aikiä, Marja; Immonen, Arto; Mervaala, Esa; Alafuzoff, Irina; Kälviäinen, Reetta

    2014-09-01

    Long-term cognitive and memory performance after surgical treatment of unilateral temporal lobe epilepsy (TLE) was investigated in a series of 98 patients. Neuropsychological evaluation was performed preoperatively and after one and three years postoperatively. Fifty-eight patients (59%) became seizure-free (Engel's class I). Verbal learning and memory declined in long-term follow-up in both left and right TLE groups. Visual memory remained stable. Ongoing postoperative seizures were related to decline in the immediate recall of logical prose, and postoperative seizure-freedom to improvement in verbal fluency in patients with left TLE. There was significant variability in the individual postoperative long-term memory performance. Left side of surgery, better baseline performance and older age at surgery were identified as risk factors for individual decline in delayed verbal memory. Selected patients undergoing surgery for drug-resistant TLE are at risk for significant postoperative memory decline especially after left temporal lobe surgery. Preoperative counseling and long-term follow-up of cognitive performance in individual patients is recommended. Additionally, more accurate predictors of individual postoperative memory performance would be needed. PMID:24953384

  9. Biocompatibility assessment of a long-term wearable artificial pump-lung in sheep.

    PubMed

    Zhou, Kang; Niu, Shuqiong; Bianchi, Giacomo; Wei, Xufeng; Garimella, Narayana; Griffith, Bartley P; Wu, Zhongjun J

    2013-08-01

    The purpose of this study was to assess the biocompatibility of a newly developed long-term wearable artificial pump-lung (APL) in a clinically relevant ovine animal model. The wearable APL device was implanted in five sheep through left thoracotomy. The device was connected between the right atrium and pulmonary artery and evaluated for 30 days. Three sheep were used as the sham control. Platelet activation was assessed by measuring platelet surface P-selectin (CD62P) expression with flow cytometry and plasma soluble P-selectin with an enzyme-linked immunosorbent assay. Thrombotic deposition on the device components and hollow fiber membranes were analyzed with digital imaging and scanning electron microscopy. Surface P-selectin of the APL and sham groups changed significantly over the study period, but without significant differences between the two groups. Soluble P-selectin for the two groups peaked in the first 24 h after the surgery. Soluble P-selectin of the APL group remained slightly elevated over the study period compared to the presurgical baseline value and was slightly higher compared to that of the sham group. Plasma free hemoglobin remained in the normal ranges in all the animals. In spite of the surgery-related alteration in laboratory tests and elevation of platelet activation status, the APL devices in all the animals functioned normally (oxygen transfer and blood pumping) during the 30-day study period. The device flow path and membrane surface were free of gross thrombus. Electron microscopy images showed only scattered thrombi on the fibers (membrane surface and weft). In summary, the APL exhibited excellent biocompatibility. Two forms of platelet activation, surgery-related and device-induced, in the animals implanted with the wearable APL were observed. The limited device-induced platelet activation did not cause gross thrombosis and impair the long-term device performance. PMID:23452221

  10. Biocompatibility Assessment of a Long-Term Wearable Artificial Pump-Lung in Sheep

    PubMed Central

    Zhou, Kang; Niu, Shuqiong; Bianchi, Giacomo; Wei, Xufeng; Garimella, Narayana; Griffith, Bartley P; Wu, Zhongjun J

    2013-01-01

    The purpose of this study was to assess the biocompatibility of a newly developed long-term wearable artificial pump-lung (APL) in a clinically relevant ovine animal mode. The wearable APL device was implanted in five sheep through a left thoracotomy. The device was connected between the right atrium (RA) and pulmonary artery (PA) and evaluated for 30 days. Three sheep were used as the sham control. Platelet activation was assessed by measuring platelet surface P-selectin (CD62P) expression with flow cytometry and plasma soluble P-selectin with an enzyme-linked immunosorbent assay (ELISA). Thrombotic deposition on the device components and hollow fiber membranes (HFM) were analyzed with digital imaging and scanning electron microscopy (SEM). Surface P-selectin of the APL and sham groups changed significantly over the study period, but without significant differences between the two groups. Soluble P-selectin for the two groups peaked in the first 24 hours after the surgery. Soluble P-selectin of the APL group remained slightly elevated over the study period compared to the pre-surgical baseline value and was slightly higher compared to that of the sham group. Plasma free hemoglobin (PFH) remained in the normal ranges in all the animals. In spite of the surgery related alteration in laboratory tests and elevation of platelet activation status, the APL devices in all the animals functioned normally (oxygen transfer and blood pumping) during the 30 day study period. The device flow path and membrane surface were free of gross thrombus. Electron microscopy images showed only scattered thrombi on the fibers (membrane surface and weft). In summary, the APL exhibited excellent biocompatibility. Two forms of platelet activation, surgery related and device induced, in the animals implanted with the wearable APL were observed. The limited device-induced platelet activation did not cause gross thrombosis and impair the long-term device performance. PMID:23452221

  11. LONG-TERM PERFORMANCE OF PERMEABLE REACTIVE BARRIERS TO REMEDIATE CONTAMINATED GROUND WATER

    EPA Science Inventory

    This research brief presents findings over the past four years at two sites where detailed investigations by the U.S. Environmental Protection Agency (U.S. EPA) have focused on the long-term performance of PRBs under a Tri-Agency Permeable Reactive Barrier Initiative (TRI). This ...

  12. Influence of Misaligned Parents' Aspirations on Long-Term Student Academic Performance

    ERIC Educational Resources Information Center

    de Boer, Hester; van der Werf, Margaretha P. C.

    2015-01-01

    This article deals with the concept of misaligned parents' aspirations, its relationship with student background characteristics, and its effects on long-term student performance. It is defined as the difference between parents' educational ambitions for their child and the child's actual capacities. Multilevel regression analyses on a sample of…

  13. Sustainability of Teacher Expectation Bias Effects on Long-Term Student Performance

    ERIC Educational Resources Information Center

    de Boer, Hester; Bosker, Roel J.; van der Werf, Margaretha P. C.

    2010-01-01

    In this article, we address the relationship between teacher expectation bias and student characteristics, its effect on long-term student performance, and the development of this effect over time. Expectation bias was defined as the difference between observed and predicted teacher expectation. These predicted expectations were estimated from a…

  14. GEOCHEMICAL AND MICROBIAL REACTIONS AFFECTING THE LONG-TERM PERFORMANCE OF IN SITU 'IRON BARRIERS'

    EPA Science Inventory

    The in situ application of granular iron (Fe0) has become popular for the destruction of halogenated organic compounds for the immobilization of specific metals in groundwater. However, a knowledge gap exists concerning the long-term performance of the Fe0-barriers. The corrosi...

  15. Assessing the Long-Term Impacts of Water Quality Outreach and Education Efforts on Agricultural Landowners

    ERIC Educational Resources Information Center

    Jackson-Smith, Douglas B.; McEvoy, Jamie P.

    2011-01-01

    We assess the long-term effectiveness of outreach and education efforts associated with a water quality improvement project in a watershed located in northern Utah, USA. Conducted 15 years after the original project began, our research examines the lasting impacts of different extension activities on landowners' motivations to participate and…

  16. A Modified Global Assessment of Functioning (GAF) Scale for Use in Long-Term Care Settings

    ERIC Educational Resources Information Center

    Mossbarger, Brad

    2005-01-01

    Terminology in the Global Assessment of Functioning (GAF) Scale of DSM-IV often is irrelevant to the realities of nursing homes, assisted living centers, and similar facilities in which residents encounter stressors that are unique to their living environment and circumstances. As the mental health needs of long-term care residents are…

  17. Quantitative Assessment of Countermeasure Efficacy for Long-Term Space Missions

    NASA Technical Reports Server (NTRS)

    Feiveson, Alan H.

    2000-01-01

    This slide presentation reviews the development of quantitative assessments of the effectiveness of countermeasures (CM) for the effects of space travel on humans for long term space missions. An example of bone mineral density (BMD) is examined to show specific quantitative measures for failure and success.

  18. Assessing the Long-Term Effects of an Environmental Education Program: A Pragmatic Approach.

    ERIC Educational Resources Information Center

    Westphal, Joanne M.; Halverson, Wesley F.

    1986-01-01

    Examines the nature and extent of behavioral changes exhibited by participants of an action oriented environmental program which focused on Lake Michigan's water quality. Outlines the program's objectives and assesses long-term behavioral modifications resulting from involvement in the decision-making process. (ML)

  19. Editorial: Assessment Issues and Long-Term Effects of Childhood Abuse and Neglect.

    ERIC Educational Resources Information Center

    Jones, David P. H.

    1997-01-01

    This editorial reviews and comments on three recent studies: two on assessment issues or areas of diagnostic difficulty for pediatricians concerned with child abuse and neglect, and one on the long-term effects of childhood abuse and experiences of early attachment. (DB)

  20. Development of a Self-Assessment Tool to Facilitate Decision-Making in Choosing a Long Term Care Administration Major

    ERIC Educational Resources Information Center

    Johs-Artisensi, Jennifer L.; Olson, Douglas M.; Nahm, Abraham Y.

    2016-01-01

    Long term care administrators need a broad base of knowledge, skills, and interests to provide leadership and be successful in managing a fiscally responsible, quality long term care organization. Researchers developed a tool to help students assess whether a long term care administration major is a compatible fit. With input from professionals in…

  1. Evaluation of the long-term performance of six alternative disposal methods for LLRW

    SciTech Connect

    Kossik, R.; Sharp, G.; Chau, T.

    1995-12-31

    The State of New York has carried out a comparison of six alternative disposal methods for low-level radioactive waste (LLRW). An important part of these evaluations involved quantitatively analyzing the long-term (10,000 yr) performance of the methods with respect to dose to humans, radionuclide concentrations in the environment, and cumulative release from the facility. Four near-surface methods (covered above-grade vault, uncovered above-grade vault, below-grade vault, augered holes) and two mine methods (vertical shaft mine and drift mine) were evaluated. Each method was analyzed for several generic site conditions applicable for the state. The evaluations were carried out using RIP (Repository Integration Program), an integrated, total system performance assessment computer code which has been applied to radioactive waste disposal facilities both in the U.S. (Yucca Mountain, WIPP) and worldwide. The evaluations indicate that mines in intact low-permeability rock and near-surface facilities with engineered covers generally have a high potential to perform well (within regulatory limits). Uncovered above-grade vaults and mines in highly fractured crystalline rock, however, have a high potential to perform poorly, exceeding regulatory limits.

  2. Long-term performance data and analysis of CIS/CIGS modules deployed outdoors

    NASA Astrophysics Data System (ADS)

    del Cueto, J. A.; Rummel, S.; Kroposki, B.; Anderberg, A.

    2008-08-01

    The long-term performance data of copper indium diselenide (CIS) and gallium-alloyed CIS (CIGS) photovoltaic (PV) modules are investigated to assess the reliability of this technology. We study and report on numerous PV modules acquired from two manufacturers (A and B), deployed at NREL's outdoor test facility (OTF) in various configurations in the field: some are free standing, loaded with a fixed resistance and periodically tested indoors at STC; other modules are connected to data acquisition systems with their performance continuously monitored. Performance is characterized using current-voltage (I-V) measurements obtained either at standard test conditions or under real-time monitoring conditions: the power parameters plus other factors relating to quality like diode quality factors or series resistance are analyzed for changes against time. Using standard diode analysis to determine the sources of degradation indicates that CIS modules can exhibit between moderate and negligible degradation, with the dominant loss mode being fill factor declines along with decreases in open-circuit voltage, for illumination intensities near 1-sun. At lower intensities, current losses can appear appreciable. The real-time performance data also indicate that fill factor loss is the primary degradation mode, generally as a result of increases in series resistance.

  3. Relationship between cognitive impairment and nutritional assessment on functional status in Calabrian long-term-care

    PubMed Central

    Malara, Alba; Sgrò, Giovanni; Caruso, Chiara; Ceravolo, Francesco; Curinga, Giuseppe; Renda, Grazia Francesca; Spadea, Fausto; Garo, Michele; Rispoli, Vincenzo

    2014-01-01

    Objective The interaction between dementia and nutritional state is very complex and not yet fully understood. The aim of the present study was to assess the interaction between cognitive impairment and nutritional state in a cohort of residential elderly in relationship with functional condition of patients and their load of assistance in long-term-care facilities of the National Association of Third Age Structures (ANASTE) Calabria. Methods One hundred seventy-four subjects (122 female and 52 male) were admitted to the long-term-care ANASTE Calabria study. All patients underwent multidimensional geriatric assessment. Nutritional state was assessed with the Mini Nutritional Assessment (MNA), whereas cognitive performance was evaluated by the Mini-Mental State Examination (MMSE). The functional state was assessed by Barthel Index (BI) and Activity Daily Living (ADL). The following nutritional biochemical parameters were also evaluated: albumin, cholesterol, iron, and hemoglobin. All patients were reassessed 180 days later. Results A severe cognitive impairment in MMSE performance was displayed in 49.7% patients, while 39.8% showed a moderate deficit; 6.9% had a slight deficit; and 3.4% evidenced no cognitive impairment. In MNA, 30% of patients exhibited an impairment of nutritional state; 56% were at risk of malnutrition; and 14% showed no nutritional problems. Malnutrition was present in 42% of patients with severe cognitive impairment, but only 4% of malnourished patients showed moderate cognitive deficit. The statistical analysis displayed a significant correlation between MNA and MMSE (P<0.001), as did MMSE correlated with Activity Daily Living (P<0.001) and BI (P<0.05). MNA correlated with BI (P<0.001) and albumin (P<0.001). The follow-up showed a strong correlation between cognitive deterioration and worsening of nutritional state (P<0.005) as well as with the functional state (P<0.05) and mortality (P<0.01). Conclusion The present study clearly shows that

  4. Training for sustained performance: moving toward long-term musician development.

    PubMed

    Clark, Terry; Lisboa, Tánia

    2013-09-01

    Success in the performing arts, like sports, is dependent upon the acquisition and consistent use of a diverse range of skills. In sports, an understanding of safe and effective use of the body is required to facilitate long-term involvement in that activity. In order to assist athletes to attain their performance goals, and ensure healthy and sustained involvement, long-term athlete development (LTAD) models have been devised and adapted by professional sporting bodies throughout the world. LTAD models emphasize the intellectual, emotional, and social development of the athlete, encourage long-term participation in physical activities, and enable participants to improve their overall health and well-being and increase their life-long participation in physical activity. At present there is no such long-term development model for musicians. Yet musicians must cope with a multitude of career-related physical and mental demands, and performance-related injuries and career burnout are rife within the profession. Despite this, musicians' training rarely addresses such issues and musicians are left largely to learn about them through either chance or accrued experience. This paper discusses key concepts and recommendations in LTAD models, together with music-specific research highlighting the need for the development of a comprehensive long-term approach to musicians' training. The results of a survey of existing music training programs are compared to recommendations and the different development stages in LTAD models. Finally, implementation science is introduced as a methodological option for identifying how best to communicate the body of evidence-based knowledge concerning healthy and effective music-making to young student musicians. PMID:24013288

  5. On the need for uncertainty assessment of long-term eddy-covariance measurements

    NASA Astrophysics Data System (ADS)

    Mauder, Matthias; Cuntz, Matthias; Drüe, Clemens; Graf, Alexander; Rebmann, Corinna; Schmid, Hans Peter; Schmidt, Marius; Steinbrecher, Rainer

    2013-04-01

    Eddy-covariance measurements are routinely performed worldwide on a long-term basis, in order to observe ecosystem exchange of trace gases, water and energy. The data obtained are needed to validate or constrain process-based models and for evaluating ecosystem budgets. There is a strong demand for consistent and comprehensive quality flagging and uncertainty quantification to assure comparability of datasets from different sites. We review established quality assessment procedures and suggest a newly composed strategy comprising tests on high-frequency raw data, tests on statistics, fluxes and corrections. Additionally, we quantify different types of errors. This strategy will be applied within the recently launched TERENO network of ecosystem observatories. Five test datasets from TERENO and CarboEurope-IP were subjected to the specific quality assessment scheme. These datasets include two different sonic types, open- and closed-path instruments, tall and low vegetation, flat and complex terrain. We show the robustness and applicability of the scheme to data acquired with the different measurement set-ups. Coherences between established flagging schemes and newly added error determination are demonstrated. This uncertainty assessment for each flux estimate represents an indispensable value for modeling as well as for budgeting fluxes.

  6. Designing long-term fish community assessments in connecting channels: Lessons from the Saint Marys River

    USGS Publications Warehouse

    Schaeffer, Jeff; Rogers, Mark W.; Fielder, David G.; Godby, Neal; Bowen, Anjanette K.; O'Connor, Lisa; Parrish, Josh; Greenwood, Susan; Chong, Stephen; Wright, Greg

    2014-01-01

    Long-term surveys are useful in understanding trends in connecting channel fish communities; a gill net assessment in the Saint Marys River performed periodically since 1975 is the most comprehensive connecting channels sampling program within the Laurentian Great Lakes. We assessed efficiency of that survey, with intent to inform development of assessments at other connecting channels. We evaluated trends in community composition, effort versus estimates of species richness, ability to detect abundance changes for four species, and effects of subsampling yellow perch catches on size and age-structure metrics. Efficiency analysis revealed low power to detect changes in species abundance, whereas reduced effort could be considered to index species richness. Subsampling simulations indicated that subsampling would have allowed reliable estimates of yellow perch (Perca flavescens) population structure, while greatly reducing the number of fish that were assigned ages. Analyses of statistical power and efficiency of current sampling protocols are useful for managers collecting and using these types of data as well as for the development of new monitoring programs. Our approach provides insight into whether survey goals and objectives were being attained and can help evaluate ability of surveys to answer novel questions that arise as management strategies are refined.

  7. The long-term performance degradation of a radioisotope thermoelectric generator using silicon germanium

    NASA Technical Reports Server (NTRS)

    Stapfer, G.; Truscello, V. C.

    1976-01-01

    The successful utilization of a radioisotope thermoelectric generator (RTG) as the power source for spaceflight missions requires that the performance of such an RTG be predictable throughout the mission. Several mechanisms occur within the generator which tend to degrade the performance as a function of operating time. The impact which these mechanisms have on the available output power of an RTG depends primarily on such factors as time, temperature and self-limiting effects. The relative magnitudes, rates and temperature dependency of these various degradation mechanisms have been investigated separately by coupon experiments as well as 4-couple and 18-couple module experiments. This paper discusses the different individual mechanisms and summarizes their combined influence on the performance of an RTG. Also presented as part of the RTG long-term performance characteristics is the sensitivity of the available RTG output power to variations of the individual degradation mechanisms thus identifying the areas of greatest concern for a successful long-term mission.

  8. Long-term performance of epoxy-bonded rebar-couplers

    NASA Astrophysics Data System (ADS)

    Brungraber, Griffin Rupp

    Rebar-couplers mechanically splice pairs of steel reinforcing bars, end-to-end; they are used regularly in reinforced concrete construction. Epoxy-bonded couplers are one available type, but have unique long-term performance considerations. The adhesive material used in these couplers is a two-part, field-mixed, ambient-cure epoxy system, originally designed for adhesive anchorage to concrete. Many of the adhesive systems used for anchorage to concrete, including the system used with adhesive-bonded couplers, are epoxy systems. The mechanical properties of these types of epoxies have been shown to degrade over time, in the presence of moisture. A variety of commercially available adhesive systems, for anchorage to concrete, were studied to assess their relative resistance to moisture-based degradation. The material properties of two of the adhesive systems, both epoxies, and the performance of the rebar-couplers were then measured over a fourteen-and-a-half-month period of exposure to a variety of environmental conditions, including water immersion at a range of temperatures. From these results, material degradation models were used to predict the properties of the adhesive over the service life of the rebar-coupler. A Finite Element Analysis (FEA) model was developed to simulate the tensile failure of the epoxy-bonded rebar-coupler system and correlate degrading adhesive material properties to changes in the coupler system's behavior throughout its service life.

  9. The long-term performance of nuclear waste forms: Natural materials - three case studies

    SciTech Connect

    Ewing, R.C.

    1993-12-31

    Natural materials may be used to advantage in the evaluation of the long-term performance of nuclear waste forms. Three case studies are presented: (I) radiation effects in ceramic waste forms; (II) corrosion products of UO{sub 2} under oxic conditions; (III) corrosion rate of nuclear waste glasses. For each case, a natural phase which is structurally and chemically analogous to the waste form is identified and used to evaluate the long-term behavior of a nuclear waste form. Short-term experimental results are compared to the observations made of analogous natural phases. The three cases studies illustrate that results ma range between providing fundamental data needed for the long-term evaluation of a waste form to only providing qualitative data of limited use. Although in the most rigorous view the long-term behavior of a phase cannot be predicted, the correspondence between short-term experimental results and observations made of natural phases provides confidence in the {open_quotes}predicted{close_quotes} behavior of the waste form. The strength of this approach rests with the degree to which a mechanistic understanding of the phenomenon is attained.

  10. Long-Term Assessment of Critical Radionuclides and Associated Environmental Media at the Savannah River Site

    SciTech Connect

    Jannik, G. T.; Baker, R. A.; Lee, P. L.; Eddy, T. P.; Blount, G. C.; Whitney, G. R.

    2012-11-06

    During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities. However, only a relatively small number of the released radionuclides have been significant contributors to doses and risks to the public. At SRS dose and risk assessments indicate tritium oxide in air and surface water, and Cs-137 in fish and deer have been, and continue to be, the critical radionuclides and pathways. In this assessment, indepth statistical analyses of the long-term trends of tritium oxide in atmospheric and surface water releases and Cs-137 concentrations in fish and deer are provided. Correlations also are provided with 1) operational changes and improvements, 2) geopolitical events (Cold War cessation), and 3) recent environmental remediation projects and decommissioning of excess facilities. For example, environmental remediation of the F- and H-Area Seepage Basins and the Solid Waste Disposal Facility have resulted in a measurable impact on the tritium oxide flux to the onsite Fourmile Branch stream. Airborne releases of tritium oxide have been greatly affected by operational improvements and the end of the Cold War in 1991. However, the effects of SRS environmental remediation activities and ongoing tritium operations on tritium concentrations in the environment are measurable and documented in this assessment. Controlled hunts of deer and feral hogs are conducted at SRS for approximately six weeks each year. Before any harvested animal is released to a hunter, SRS personnel perform a field analysis for Cs-137 concentrations to ensure the hunter's dose does not exceed the SRS administrative game limit of 0.22 millisievert (22 mrem). However, most of the Cs-137 found in SRS onsite deer is not from site operations but is from nuclear weapons testing fallout from the 1950's and early 1960's. This legacy source term is trended in the SRS deer, and an assessment of the ''effective'' half-life of Cs-137 in deer

  11. A case study comparing a randomized withdrawal trial and a double-blind long-term trial for assessing the long-term efficacy of an antidepressant.

    PubMed

    Mallinckrodt, Craig; Chuang-Stein, Christy; McSorley, Paul; Schwartz, Jeffrey; Archibald, Donald G; Perahia, David G; Detke, Michael J; Alphs, Larry

    2007-01-01

    Assessing long-term efficacy in psychiatric drugs involves a number of complex questions, and the priaority of these questions is different for different disorders and for different stakeholders. Therefore, it is essential that we not adopt a one-method-fits-all approach, but rather adapt the specific details of the designs and analysis of data from long-term trials to individual disease states. Randomized withdrawal (RW) designs, even though addressing a specific question of particular interest, face some difficult methodological and ethical challenges. A less common alternative design, termed the double-blind long-term efficacy (DBLE) design, is logistically similar to traditional responder extension designs. However, use of an analytic approach that includes all randomized patients rather than only the selected subset that continued beyond acute treatment avoids the major criticism of the extender design. The present paper illustrates the attributes of the RW and DBLE designs by analyzing data from trials adopting these designs. The RW and DBLE designs address different questions, and are thus not directly comparable. Potential benefits of the DBLE design include: (1) the parsimonious use of patients and the resultant reduced exposure to placebo as each patient can contribute to multiple developmental objectives; (2) the results are generalizable to actual clinical practice as the design matches treatment guidelines; and, (3) results of safety assessments are meaningful as they involve all randomized patients. Our case study suggests that the DBLE design can provide definitive answers to important questions and may be a useful design for assessing long-term treatment effects. PMID:17238129

  12. Evaluating the Long-Term Performance of Geosynethic Clay Liners Exposed to Freeze-Thaw

    SciTech Connect

    Robert K. Podgorney; Jesse E. Bennett

    2006-02-01

    Geosynethic clay liners have become an increasingly common component in landfill liner and cover systems since their introduction in the early 1980’s. An important consideration for landfills and covers constructed in the frost zone of cold climates is the possible deterioration in performance due to freeze-thaw cycling over the design life of the liner or cover system, which can be up to 1,000 years. The literature contains several examples showing that geosynethic clay liners can withstand a limited number of freeze-thaw events, but data on long-term performance are lacking The objective of this study was to examine the long-term performance of geosynethic clay liners exposed to repeated freeze-thaw cycles, encompassing their application as a final cover as well as a bottom liner. Laboratory analysis of hydraulic conductivity was performed after as many as 150 freeze-thaw cycles, with no appreciable changes observed. Based upon an analytical heat transfer analysis, this equates to [at least] 150 years of field service for placement depths greater then approximately 30 cm below the surface of the liner. The long-term insusceptibility of GCLs to increased hydraulic conductivity as a response to repeated freeze-thaw cycling is largely due to the self-healing characteristics of the sodium bentonite used in their construction. GCLs perform well and maintain efficiency as a barrier to flow after 150 freeze-thaw cycles. Other factors, such as permeant chemistry, physical disturbance, desiccation, etc., may be much more important factors to consider when planning for the long-term performance of GCLs.

  13. Working memory training shows immediate and long-term effects on cognitive performance in children

    PubMed Central

    Pugin, Fiona; Metz, Andreas J.; Stauffer, Madlaina; Wolf, Martin; Jenni, Oskar G.; Huber, Reto

    2014-01-01

    Working memory is important for mental reasoning and learning processes. Several studies in adults and school-age children have shown performance improvement in cognitive tests after working memory training. Our aim was to examine not only immediate but also long-term effects of intensive working memory training on cognitive performance tests in children. Fourteen healthy male subjects between 10 and 16 years trained a visuospatial n-back task over 3 weeks (30 min daily), while 15 individuals of the same age range served as a passive control group. Significant differences in immediate (after 3 weeks of training) and long-term effects (after 2-6 months) in an auditory n-back task were observed compared to controls (2.5 fold immediate and 4.7 fold long-term increase in the training group compared to the controls). The improvement was more pronounced in subjects who improved their performance during the training. Other cognitive functions (matrices test and Stroop task) did not change when comparing the training group to the control group. We conclude that visuospatial working memory training in children boosts performance in similar memory tasks such as the auditory n-back task. The sustained performance improvement several months after the training supports the effectiveness of the training. PMID:25671082

  14. Design Principles and Concepts for Enhancing Long-Term Cap Performance and Confidence

    SciTech Connect

    Steven J. Piet; Robert P. Breckenridge; Gregory J. White; Jacob J. Jacobson; Hilary I. Inyang

    2005-10-01

    The siting of new landfills is becoming increasing difficult as the public and stakeholders want more confidence of performance for longer times and landfill owners want to store more waste in the least area while knowing and limiting their long-term liabilities. These changes motivate re-examination of long-term performance mechanisms and their implications for cap and barrier designs. Accordingly, in this paper we first consider design principles from the standpoint of long-term performance and management, including the ability to monitor and repair barriers. We then consider some design concepts that may implement these principles, especially evapo-transpiration (ET) caps. We suggest five design principles based on experience in the cap and barrier field as well as other engineering disciplines. These principles are as follows: · Establish a clear and defendable design basis. · Design for ease of monitoring and repair. · Analyze the barrier as a dynamic system, not static. · Work with nature, not against. · Recognize that increased complexity can reduce, not enhance, net performance. ET caps are an excellent embodiment of these design principles. We apply the design principles to ET caps, as well as variants such as erosion armor, capillary breaks, bio-intrusion layers, and low permeability material layers.

  15. 9975 SHIPPING PACKAGE PERFORMANCE OF ALTERNATE MATERIALS FOR LONG-TERM STORAGE APPLICATION

    SciTech Connect

    Skidmore, E.; Hoffman, E.; Daugherty, W.

    2010-02-24

    The Model 9975 shipping package specifies the materials of construction for its various components. With the loss of availability of material for two components (cane fiberboard overpack and Viton{reg_sign} GLT O-rings), alternate materials of construction were identified and approved for use for transport (softwood fiberboard and Viton{reg_sign} GLT-S O-rings). As these shipping packages are part of a long-term storage configuration at the Savannah River Site, additional testing is in progress to verify satisfactory long-term performance of the alternate materials under storage conditions. The test results to date can be compared to comparable results on the original materials of construction to draw preliminary conclusions on the performance of the replacement materials.

  16. Modeling the Long-Term Isolation Performance of Natural and Engineered Geologic CO2 Storage Sites

    SciTech Connect

    Johnson, J W; Nitao, J J; Morris, J P

    2004-07-26

    Long-term cap rock integrity represents the single most important constraint on the long-term isolation performance of natural and engineered geologic CO{sub 2} storage sites. CO{sub 2} influx that forms natural accumulations and CO{sub 2} injection for EOR/sequestration or saline-aquifer disposal both lead to concomitant geochemical alteration and geomechanical deformation of the cap rock, enhancing or degrading its seal integrity depending on the relative effectiveness of these interdependent processes. This evolution of cap-rock permeability can be assessed through reactive transport modeling, an advanced computational method based on mathematical models of the coupled physical and chemical processes catalyzed by the influx event. Using our reactive transport simulator (NUFT), supporting geochemical databases and software (SUPCRT92), and distinct-element geomechanical model (LDEC), we have shown that influx-triggered mineral dissolution/precipitation reactions within typical shale cap rocks continuously reduce microfrac apertures, while pressure and effective-stress evolution first rapidly increase then slowly constrict them. For a given shale composition, the extent of geochemical enhancement is nearly independent of key reservoir properties (permeability and lateral continuity) that distinguish saline aquifer and EOR/sequestration settings and CO{sub 2} influx parameters (rate, focality, and duration) that distinguish engineered disposal sites and natural accumulations, because these characteristics and parameters have negligible impact on mineral reaction rates. In contrast, the extent of geomechanical degradation is highly dependent on these reservoir properties and influx parameters, because they effectively dictate magnitude of the pressure perturbation. Specifically, initial geomechanical degradation has been shown inversely proportional to reservoir permeability and lateral continuity and proportional to influx rate. As a result, while the extent of

  17. Macrophagic myofasciitis lesions assess long-term persistence of vaccine-derived aluminium hydroxide in muscle.

    PubMed

    Gherardi, R K; Coquet, M; Cherin, P; Belec, L; Moretto, P; Dreyfus, P A; Pellissier, J F; Chariot, P; Authier, F J

    2001-09-01

    Macrophagic myofasciitis (MMF) is an emerging condition of unknown cause, detected in patients with diffuse arthromyalgias and fatigue, and characterized by muscle infiltration by granular periodic acid-Schiff's reagent-positive macrophages and lymphocytes. Intracytoplasmic inclusions have been observed in macrophages of some patients. To assess their significance, electron microscopy was performed in 40 consecutive cases and chemical analysis was done by microanalysis and atomic absorption spectrometry. Inclusions were constantly detected and corresponded to aluminium hydroxide, an immunostimulatory compound frequently used as a vaccine adjuvant. A lymphocytic component was constantly observed in MMF lesions. Serological tests were compatible with exposure to aluminium hydroxide-containing vaccines. History analysis revealed that 50 out of 50 patients had received vaccines against hepatitis B virus (86%), hepatitis A virus (19%) or tetanus toxoid (58%), 3-96 months (median 36 months) before biopsy. Diffuse myalgias were more frequent in patients with than without an MMF lesion at deltoid muscle biopsy (P < 0.0001). Myalgia onset was subsequent to the vaccination (median 11 months) in 94% of patients. MMF lesion was experimentally reproduced in rats. We conclude that the MMF lesion is secondary to intramuscular injection of aluminium hydroxide-containing vaccines, shows both long-term persistence of aluminium hydroxide and an ongoing local immune reaction, and is detected in patients with systemic symptoms which appeared subsequently to vaccination. PMID:11522584

  18. Modeling and Simulation of Long-Term Performance of Near-Surface Barriers

    SciTech Connect

    Piet, S. J.; Jacobson, J. J.; Martian, P.; Martineau, R.; Soto, R.

    2003-02-25

    INEEL started a new project on long-term barrier integrity in April 2002 that aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late, prior to system-level failure). This paper describes our computer simulation approach for better understanding the relationships and dynamics between the various components and management decisions in a cap. The simulation is designed to clarify the complex relationships between the various components within the cap system and the various management practices that affect the barrier performance. We have also conceptualized a time-dependent 3-D simulation with rigorous solution to unsaturated flow physics with complex surface boundary conditions.

  19. Modeling and Simulation of Long-Term Performance of Near-Surface Barriers

    SciTech Connect

    Piet, Steven James; Jacobson, Jacob Jordan; Soto, Rafael; Martian, Pete; Martineau, Richard Charles

    2003-02-01

    , the INEEL started a new project on long-term barrier integrity in April 2002 that aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late, prior to system-level failure). This paper describes our computer simulation approach for better understanding the relationships and dynamics between the various components and management decisions in a cap. The simulation is designed to clarify the complex relationships between the various components within the cap system and the various management practices that affect the barrier performance. We have also conceptualized a time-dependent 3-D simulation with rigorous solution to unsaturated flow physics with complex surface boundary conditions.

  20. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition.

    PubMed

    Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

    2016-01-01

    Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition. PMID:26869978

  1. ASSESSMENT OF LONG-TERM SALINITY CHANGES IN AN IRRIGATED STREAM-AQUIFER SYSTEM.

    USGS Publications Warehouse

    Konikow, Leonard F.; Person, Mark

    1985-01-01

    Changes in salinity in groundwater and surface water in the Arkansas River valley of southeastern Colorado are primarily related to irrigation practices. A solute transport model was applied to an 11-mile reach of the valley to compute salinity changes in response to spatially and temporally varying stresses. The model was calibrated in 1973 using detailed field measurements made during 1971 and 1972. In 1973 the calibrated model was used to predict that a gradual long-term increase in groundwater salinity of about 2-3% per year would occur if the observed irrigation practices continued. The study area was resampled during the winter of 1982 to help evaluate if any long-term changes in salinity are actually occurring. Nonparametric and parametric statistical tests were used to help assess the significance of observed changes in groundwater salinity.

  2. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition

    PubMed Central

    Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

    2016-01-01

    Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance–contingent reward in a test can undermine long-term knowledge acquisition. PMID:26869978

  3. Assessment of long-term leaching from waste incineration air-pollution-control residues.

    PubMed

    Astrup, T; Mosbaek, H; Christensen, T H

    2006-01-01

    Assessment of long-term leaching from MSWI air-pollution-control (APC) residues is discussed with respect to use in environmental impact assessment, such as life-cycle assessment (LCA). A method was proposed for estimating leaching as a function of the liquid-to-solid (L/S) ratio in a long-term perspective (L/S 5000l/kg). Data for changes in residue pH as a function of L/S was used in combination with pH dependent leaching data to predict leachate concentrations of Al, Ca, Cd, Ba, Mg, Ni, Pb, S, Pb, V and Zn as a function of L/S. Mass balance calculations were used to determine the element fractions leached with respect to L/S. The estimated long-term leaching from a semi-dry residue and a fly ash was compared with short-term leaching determined by batch tests at L/S 10l/kg, both carbonated and non-carbonated versions of the residues were investigated. Generally, very high L/S ratios above 2000l/kg were required to leach 20-30% of the solid contents. However, Ca and S were depleted at L/S 200-900l/kg. The long-term leachate concentrations were found to either remain at the same level as the initial leaching determined by the L/S 10 batch test, or to significantly decrease compared with the initial leaching. Only Al and Zn were found to show higher leachate concentrations at L/S ratios above 3000-5000l/kg. Carbonation generally prolonged the time needed for depletion from the solid residues; however, Ca and S were depleted faster than in the case of non-carbonated residues. This study shows that uncritical use of batch leaching data for assessing the potential leaching is highly problematic, and evaluations of residue disposal should include scenario specific quantification of the long-term leaching. PMID:16488595

  4. Shifting the Paradigm for Long Term Monitoring at Legacy Sites to Improve Performance while Reducing Cost

    SciTech Connect

    Eddy-Dilek, Carol A.; Looney, Brian B.; Seaman, John; Kmetz, Thomas

    2013-01-10

    A major issue facing many government and private industry sites that were previously contaminated with radioactive and chemical wastes is that often the sites cannot be cleaned up enough to permit unrestricted human access. These sites will require long-term management, in some cases indefinitely, leaving site owners with the challenge of protecting human health and environmental quality in a cost effective manner. Long-term monitoring of groundwater contamination is one of the largest projected costs in the life cycle of environmental management at the Savannah River Site (SRS), the larger DOE complex, and many large federal and private sites. Currently, most monitoring strategies are focused on laboratory measurements of contaminants measured in groundwater samples collected from wells. This approach is expensive, and provides limited and lagging information about the effectiveness of cleanup activities and the behavior of the residual contamination. Over the last twenty years, DOE and other federal agencies have made significant investments in the development of various types of sensors and strategies that would allow for remote analysis of contaminants in groundwater, but these approaches do not promise significant reductions in risk or cost. Scientists at SRS have developed a new paradigm to simultaneously improve the performance of long term monitoring systems while lowering the overall cost of monitoring. This alternative approach incorporates traditional point measurements of contaminant concentration with measurements of controlling variables including boundary conditions, master variables, and traditional plume/contaminant variables. Boundary conditions are the overall driving forces that control plume movement and therefore provide leading indication to changes in plume stability. These variables include metrics associated with meteorology, hydrology, hydrogeology, and land use. Master variables are the key variables that control the chemistry of the

  5. THE IMMEDIATE AND LONG-TERM EFFECTS OF KINESIOTAPE® ON BALANCE AND FUNCTIONAL PERFORMANCE

    PubMed Central

    Douris, Peter; Fukuroku, Taryn; Kuzniewski, Michael; Dias, Joe; Figueiredo, Patrick

    2016-01-01

    Background The application of Kinesio Tex® tape (KT) results, in theory, in the improvement of muscle contractibility by supporting weakened muscles. The effect of KT on muscle strength has been investigated by numerous researchers who have theorized that KT facilitates an immediate increase in muscle strength by generating a concentric pull on the fascia. The effect of KT on balance and functional performance has been controversial because of the inconsistencies of tension and direction of pull required during application of KT and whether its use on healthy individuals provides therapeutic benefits. Hypotheses/Purpose The purpose of the present study was to investigate the immediate and long-term effects of the prescribed application (for facilitation) of KT when applied to the dominant lower extremity of healthy individuals. The hypothesis was that balance and functional performance would improve with the prescribed application of KT versus the sham application. Study Design Pretest-posttest repeated measures control group design. Methods Seventeen healthy subjects (9 males; 8 females) ranging from 18-35 years of age (mean age 23.3 ± 0.72), volunteered to participate in this study. KT was applied to the gastrocnemius of the participant's dominant leg using a prescribed application to facilitate muscle performance for the experimental group versus a sham application for the control group. The Biodex Balance System and four hop tests were utilized to assess balance, proprioception, and functional performance beginning on the first day including pre- and immediately post-KT application measurements. Subsequent measurements were performed 24, 72, and 120 hours after tape application. Repeated measures ANOVA's were performed for each individual dependent variable. Results There were no significant differences for main and interaction effects between KT and sham groups for the balance and four hop tests. Conclusion The results of the present study did not

  6. Improvement of capabilities of the Distributed Electrochemistry Modeling Tool for investigating SOFC long term performance

    SciTech Connect

    Gonzalez Galdamez, Rinaldo A.; Recknagle, Kurtis P.

    2012-04-30

    This report provides an overview of the work performed for Solid Oxide Fuel Cell (SOFC) modeling during the 2012 Winter/Spring Science Undergraduate Laboratory Internship at Pacific Northwest National Laboratory (PNNL). A brief introduction on the concept, operation basics and applications of fuel cells is given for the general audience. Further details are given regarding the modifications and improvements of the Distributed Electrochemistry (DEC) Modeling tool developed by PNNL engineers to model SOFC long term performance. Within this analysis, a literature review on anode degradation mechanisms is explained and future plans of implementing these into the DEC modeling tool are also proposed.

  7. Using the balanced scorecard to align strategy and performance in long-term care.

    PubMed

    Macdonald, M

    1998-01-01

    The Sisters of Charity of Ottawa Health Service (SCOHS) is a Canadian health care corporation that has adapted Kaplan and Norton's balanced scorecard to enhance strategic management and measurement in a multisite health care facility comprising long term care, continuing complex care, rehabilitative services, palliative care and ambulatory care. This article discusses how the SCOHS has incorporated the following principles into the balanced scorecard: demonstration of cause and effect; inclusion of outcomes and performance drivers; linkage to fiscal and utilization indicators; and integration of the mission and values of the organization. Examples of corporate level outcomes and performance measures are provided in the form of lead and lag indicators. PMID:10187659

  8. Evaluation of the long-term sound reduction performance of resilient materials in floating floor systems

    NASA Astrophysics Data System (ADS)

    Lee, Jung-Yoon; Kim, Jong-Mun; Kim, Jinyoung; Kim, Jeongho

    2016-03-01

    Building multi-dwelling units is one of the practical engineering solutions to housing shortage in urban areas with high population density. However, noise from upstairs is a major issue. The use of resilient materials in floating floor structures is recognized as an effective method to reduce such noise. In general, soft materials are considered as better resilient materials due to their superior performance in impact sound reduction. However, it is often overlooked that the sound reduction performance of soft resilient materials is susceptible to being degraded over time when subjected to a long-term load. In this study, the long-term performance of eight resilient materials is evaluated by monitoring their dynamic stiffness for 270 days under the two sustained load conditions: 250 N and 500 N. According to the experimental study, the dynamic stiffness increases consistently with loading time for all resilient materials. This leads to a decrease in the sound reduction performance. More rapid reduction in the dynamic stiffness and hence in the sound reduction performance is observed when a larger sustained load is applied. A greater decrease in the sound reduction performance is found in soft resilient materials.

  9. Comparison of an oxygen concentrator and wall oxygen in the assessment of patients undergoing long term oxygen therapy assessment.

    PubMed

    Bolton, C E; Annandale, J A; Ebden, P

    2006-01-01

    Long term oxygen therapy (LTOT) is a recognised management option for hypoxaemic patients with chronic respiratory disease. Formal assessment is required which is usually conducted in the hospital and performed on piped oxygen to ensure correction of the hypoxaemia. However, an oxygen concentrator is the standard oxygen source for the patient at home who requires LTOT. The oxygen concentration delivered is lower from a concentrator than piped oxygen. Here, we present a study of ten hypoxaemic patients using both delivery sources in a cross-over design. The partial pressure of oxygen was lower in patients when receiving oxygen from a concentrator, p < 0.05. This encourages the Clinician to consider formal assessments on an oxygen concentrator in order to ensure that the hypoxaemia will be corrected when they are prescribed a concentrator for home use. PMID:16509177

  10. An Account of Performance in Accessing Information Stored in Long-Term Memory. A Fixed-Links Model Approach

    ERIC Educational Resources Information Center

    Altmeyer, Michael; Schweizer, Karl; Reiss, Siegbert; Ren, Xuezhu; Schreiner, Michael

    2013-01-01

    Performance in working memory and short-term memory tasks was employed for predicting performance in a long-term memory task in order to find out about the underlying processes. The types of memory were represented by versions of the Posner Task, the Backward Counting Task and the Sternberg Task serving as measures of long-term memory, working…

  11. Predictions of long-term performance of granular iron permeable reactive barriers: field-scale evaluation.

    PubMed

    Jeen, Sung-Wook; Gillham, Robert W; Przepiora, Andrzej

    2011-04-01

    Long-term performance is a key consideration for the granular iron permeable reactive barrier (PRB) technology because the economic benefit relies on sustainable operation for substantial periods of time. However, predictions on the long-term performance have been limited mainly because of the lack of reliable modeling tools. This study evaluated the predictive capability of a recently-developed reactive transport model at two field-scale PRBs, both having relatively high concentrations of dissolved carbonate in the native groundwater. The first site, with 8 years of available monitoring data, was a funnel-and-gate installation, with a low groundwater velocity through the gate (about 0.12 m d(-1)). The loss in iron reactivity caused by secondary mineral precipitation was small, maintaining relatively high removal rates for chlorinated organics. The simulated concentrations for most constituents in the groundwater were within the range of the monitoring data. The second site, with monitoring data available for 5 years, was a continuous wall PRB, designed for a groundwater velocity of 0.9 m d(-1). A comparison of measured and simulated aqueous concentrations suggested that the average groundwater velocity through the PRB could be lower than the design value by a factor of two or more. The distribution and amounts of carbonate minerals measured in core samples supported the decreased groundwater velocity used in the simulation. The generally good agreement between the simulated and measured aqueous and solid-phase data suggest that the model could be an effective tool for predicting long-term performance of granular iron PRBs, particularly in groundwater with high concentrations of carbonate. PMID:21237528

  12. Effects of long term storage on aerospace nickel cadmium cell performance

    NASA Technical Reports Server (NTRS)

    Yi, Thomas Y.

    1987-01-01

    Evaluation of the long term effects on aerospace nickel cadmium cells is described. A number of 6Ah and 12Ah capacity cells which were stored in shorted condition for 9 to 11 years at the Goddard Space Flight Center were selected for the study. Of the three tests which were initiated (initial and final destruction analyses of the test cells, electrical characterization tests, and life cycling tests) only the electrical characterization tests are completed; the other tests are scheduled to be completed by February 1987. The preliminary electrial performance data from the life cycling test and chemical composition data from the destructive testing indicate no anomalous behavior.

  13. Effects of long term storage on aerospace nickel cadmium cell performance

    NASA Astrophysics Data System (ADS)

    Yi, Thomas Y.

    1987-09-01

    Evaluation of the long term effects on aerospace nickel cadmium cells is described. A number of 6Ah and 12Ah capacity cells which were stored in shorted condition for 9 to 11 years at the Goddard Space Flight Center were selected for the study. Of the three tests which were initiated (initial and final destruction analyses of the test cells, electrical characterization tests, and life cycling tests) only the electrical characterization tests are completed; the other tests are scheduled to be completed by February 1987. The preliminary electrial performance data from the life cycling test and chemical composition data from the destructive testing indicate no anomalous behavior.

  14. Investigation of long term storage effects on aerospace nickel-cadmium cell performance

    NASA Astrophysics Data System (ADS)

    Yi, T. Y.

    1986-09-01

    A study on evaluation of the long term storage effects on aerospace nickel-cadmium cells currently being performed at NASA/Goddard Space Flight Center (GSFC) is described. A number of cells of 6 Ah and 12 Ah capacities which were stored in shorted condition for 8 to 9 years at the GSFC were selected for this study. These cells will undergo electrical acceptance testing the the GSFC, and life cycling at the NASA Battery Test Facility at the Naval Weapons Facility at the Naval Weapons Support Center (NWSC) in Crane, Indiana; in addition, some cells from the study will undergo destructive analyses.

  15. Photovoltaic module performance and durability following long-term field exposure

    SciTech Connect

    Ellibee, D.E.; Hansen, B.R.; King, D.L.; Kratochvil, J.A.; Quintana, M.A.

    1998-09-08

    Our investigations of both new and field-aged photovoltaic modules have indicated that, in general, today's commercially available modules area highly reliable product. However, by using new test procedures, subtle failure mechanisms have also been identified that must be addressed in order to achieve 30-year module lifetimes. This paper summarizes diagnostic test procedures, results, and implications of in-depth investigations of the performance and durability characteristics of commercial modules after long-term field exposure. A collaborative effort with U.S. module manufacturers aimed at achieving 30-year module lifetimes is also described.

  16. The Long-Term Performance of Small-Cell Batteries Without Cell-Balancing Electronics

    NASA Technical Reports Server (NTRS)

    Pearson, C.; Thwaite, C.; Curzon, D.; Rao, G.

    2006-01-01

    Tests approx.8 yrs ago showed Sony HC do not imbalance. AEA developed a theory (ESPC 2002): a) Self-discharge (SD) decreases with state-of-charge (SOC); b) Cells diverge to a state of dynamic equilibrium; c) Equilibrium spread depends on cell SD uniformity. Balancing model verified against test data. Short-term measures of SD difficult in Sony cells and very small values, depends on technique. Long-term evidence supports lower SD at low SD. Battery testing best proof of performance, typically mission specific tests.

  17. Investigation of long term storage effects on aerospace nickel-cadmium cell performance

    NASA Technical Reports Server (NTRS)

    Yi, T. Y.

    1986-01-01

    A study on evaluation of the long term storage effects on aerospace nickel-cadmium cells currently being performed at NASA/Goddard Space Flight Center (GSFC) is described. A number of cells of 6 Ah and 12 Ah capacities which were stored in shorted condition for 8 to 9 years at the GSFC were selected for this study. These cells will undergo electrical acceptance testing the the GSFC, and life cycling at the NASA Battery Test Facility at the Naval Weapons Facility at the Naval Weapons Support Center (NWSC) in Crane, Indiana; in addition, some cells from the study will undergo destructive analyses.

  18. Development of NH4+-sensitive polymer membranes for long-term performance microsensors

    NASA Astrophysics Data System (ADS)

    Brzozka, Zbigniew; Dawgul, Marek; Pijanowska, Dorota; Torbicz, Wladislaw

    1997-02-01

    This paper describes the development of NH4+- sensitive membranes based on various polymer materials incorporating nonactine as the ionophore for long-term performance CHEMFETs. Different composition of membranes based on plasticized PVC, carboxylated PVC, plasticized PVC modified by decylmethacrylate, polysiloxane and Siloprene were studied. Although polysiloxane membrane presented the most improved adhesion to the chip surface, the Siloprene membrane was successfully applied to design durable NH4+-sensitive CHEMFETs. These sensors showed NH4+-responses with good selectivity even after 14 months of continuous exposure to conditioning electrolyte.

  19. High-temperature MEMS Heater Platforms: Long-term Performance of Metal and Semiconductor Heater Materials

    PubMed Central

    Spannhake, Jan; Schulz, Olaf; Helwig, Andreas; Krenkow, Angelika; Müller, Gerhard; Doll, Theodor

    2006-01-01

    Micromachined thermal heater platforms offer low electrical power consumption and high modulation speed, i.e. properties which are advantageous for realizing non-dispersive infrared (NDIR) gas- and liquid monitoring systems. In this paper, we report on investigations on silicon-on-insulator (SOI) based infrared (IR) emitter devices heated by employing different kinds of metallic and semiconductor heater materials. Our results clearly reveal the superior high-temperature performance of semiconductor over metallic heater materials. Long-term stable emitter operation in the vicinity of 1300 K could be attained using heavily antimony-doped tin dioxide (SnO2:Sb) heater elements.

  20. Geoethical issues in long-term assessment of geohazards and related mitigation policies

    NASA Astrophysics Data System (ADS)

    Tinti, Stefano; Armigliato, Alberto

    2015-04-01

    Long-term assessment of large-impact and relatively (or very) infrequent geohazards like earthquakes, tsunamis and volcanic eruptions is nowadays a common practice for geoscientists and many groups have been and are involved in producing global and regional hazard maps in response of an increasing demand of the society. Though the societal needs are the basic motivations for such studies, often this aspect is not pondered enough and a lack of communication between geoscientists and the society might be a serious limit to the effective exploitation of the hazard assessment products and to the development of adequate mitigation policies. This paper is an analysis of the role of geoscientists in the process of the production of long-term assessments of dangerous natural phenomena (such as mapping of seismic, tsunami and volcanic hazards), with special emphasis given to the role of communicators and disseminators (with respect to the general public, to authorities, to restricted specialized audiences…), but also of providers of active support to the planners who should be given key elements for making decision. Geoethics imposes geoscientists to take clear and full responsibilities on the products resulting from their assessments, but also to be aware that these products are valuable insofar they are scientifically sound, known, understandable, and utilizable by a wide universe of users.

  1. Performance and Long Term Stability of Mesoporous Silica Membranes for Desalination

    PubMed Central

    Elma, Muthia; Yacou, Christelle; Diniz da Costa, João C.; Wang, David K.

    2013-01-01

    This work shows the preparation of silica membranes by a two-step sol-gel method using tetraethyl orthosilicate in ethanolic solution by employing nitric acid and ammonia as co-catalysts. The sols prepared in pH 6 resulted in the lowest concentration of silanol (Si–OH) species to improve hydrostability and the optimized conditions for film coating. The membrane was tested to desalinate 0.3–15 wt % synthetic sodium chloride (NaCl) solutions at a feed temperature of 22 °C followed by long term membrane performance of up to 250 h in 3.5 wt % NaCl solution. Results show that the water flux (and salt rejection) decrease with increasing salt concentration delivering an average value of 9.5 kg m–2 h–1 (99.6%) and 1.55 kg m–2 h–1 (89.2%) from the 0.3 and 15 wt % saline feed solutions, respectively. Furthermore, the permeate salt concentration was measured to be less than 600 ppm for testing conditions up to 5 wt % saline feed solutions, achieving below the recommended standard for potable water. Long term stability shows that the membrane performance in water flux was stable for up to 150 h, and slightly reduced from thereon, possibly due to the blockage of large hydrated ions in the micropore constrictions of the silica matrix. However, the integrity of the silica matrix was not affected by the long term testing as excellent salt rejection of >99% was maintained for over 250 h. PMID:24956942

  2. SHORT AND LONG-TERM FIRE IMPACTS ON HANFORD BARRIER PERFORMANCE

    SciTech Connect

    Ward, Anderson L.; Leary, Kevin D.; Link, Steven O.; Berlin, Gregory T.; Cammann, Jerry W.; Mandis, M. L.; Buelow, Laura C.

    2009-03-05

    A critical unknown in long-term engineered barrier use is the post-fire hydrologic function where institutional controls are in-tact but there are no resources to implement maintenance activities such as re-planting. This objective of this study was to simulate wild fire on an engineered barrier at the Hanford Site and document the post-fire changes in barrier performance. Soil physical, chemical, and hydrologic conditions; plant floristics and density; and animal use were characterized pre- and post-burn. Fuel load on the surface ranged from 4.7 to 5.71 tons/acre. Fire was initiated by drip torch and measurements of flame height and temperature were made at nine locations on the barrier surface. Flame heights exceeded 30 ft and temperatures ranged from 250 C at 1.5 cm below the surface to over 700 C at 1 m above the surface. Soil organic matter, soil wettability, and hydraulic conductivity all decreased significantly relative to pre-fire conditions. Post-fire samples showed an increase in major soil nutrients, pH, and electrical conductivity measured in 1:1 extracts whereas organic matter decreased. Decreases in wettabilty and organic matter are indicative of conditions more conducive to runoff and soil loss. The results of this study will contribute to a better understanding of post-fire recovery in a post-institutional control environment. This should lead to enhanced stakeholder acceptance regarding the long-term efficacy of ET barriers. This study will also support improvements in the design of ET barriers and performance monitoring systems. Such improvements are needed to best meet the long-term commitment to the safe in-place isolation of waste for hundreds if not thousands of years.

  3. Barrier analogs: Long-term performance issues, preliminary studies, and recommendations

    SciTech Connect

    Waugh, W.J.; Chatters, J.C.; Last, G.V.; Bjornstad, B.N.; Link, S.O.; Hunter, C.R.

    1994-02-01

    The US Department of Energy`s Hanford Protective Barrier Development Program is funding studies of natural analogs of the long-term performance of waste site covers. Natural-analog studies examine past environments as evidence for projecting the future performance of engineered structures. The information generated by analog studies is needed to (1) evaluate the designs and results of short term experiments and demonstrations, (2) formulate performance-modeling problems that bound expected changes in waste site environments, and (3) understand emergent system attributes that cannot be evaluated with short-term experiments or computer models. Waste site covers will be part of dynamic environmental systems with attributes that transcend the traits of engineered components. This report discusses results of the previously unreported preliminary studies conducted in 1983 and 1984. These results indicate that analogs could play an important role in predicting the long-term behavior of engineered waste covers. Layered exposures of glacial-flood-deposited gravels mantled with silt or sand that resemble contemporary barrier designs were examined. Bergmounds, another anomaly left by cataclysmic glacial floods, were also examined as analogs of surface gravel.

  4. A comparison of methods to assess long-term changes in Sonoran Desert vegetation

    USGS Publications Warehouse

    Munson, S.M.; Webb, R.H.; Hubbard, J.A.

    2011-01-01

    Knowledge about the condition of vegetation cover and composition is critical for assessing the structure and function of ecosystems. To effectively quantify the impacts of a rapidly changing environment, methods to track long-term trends of vegetation must be precise, repeatable, and time- and cost-efficient. Measuring vegetation cover and composition in arid and semiarid regions is especially challenging because vegetation is typically sparse, discontinuous, and individual plants are widely spaced. To meet the goal of long-term vegetation monitoring in the Sonoran Desert and other arid and semiarid regions, we determined how estimates of plant species, total vegetation, and soil cover obtained using a widely-implemented monitoring protocol compared to a more time- and resource-intensive plant census. We also assessed how well this protocol tracked changes in cover through 82 years compared to the plant census. Results from the monitoring protocol were comparable to those from the plant census, despite low and variable plant species cover. Importantly, this monitoring protocol could be used as a rapid, "off-the shelf" tool for assessing land degradation (or desertification) in arid and semiarid ecosystems.

  5. Long-term volcanic hazard assessment on El Hierro (Canary Islands)

    NASA Astrophysics Data System (ADS)

    Becerril, L.; Bartolini, S.; Sobradelo, R.; Martí, J.; Morales, J. M.; Galindo, I.

    2014-02-01

    Long-term hazard assessment, one of the bastions of risk-mitigation programs, is required for territorial planning and for developing emergency plans. To ensure qualitative and representative results, long-term volcanic hazard assessment requires several sequential steps to be completed, which include the compilation of geological and volcanological information, the characterization of past eruptions, spatial and temporal probabilistic studies, and the simulation of different eruptive scenarios. Despite being a densely populated active volcanic region that receives millions of visitors per year, no systematic hazard assessment has ever been conducted in the Canary Islands. In this paper we focus our attention on El Hierro, the youngest of the Canary Islands and the most recently affected by an eruption. We analyze the past eruptive activity (how), the spatial probability (where) and the temporal probability (when) of an eruption on the island. By studying the past eruptive behavior of the island and assuming that future eruptive patterns will be similar, we aim to identify the most likely volcanic scenarios and corresponding hazards, which include lava flows, pyroclastic fallout and pyroclastic density currents (PDCs). Finally, we estimate their probability of occurrence. The end result is the first total qualitative volcanic hazard map of the island.

  6. Long-term volcanic hazard assessment on El Hierro (Canary Islands)

    NASA Astrophysics Data System (ADS)

    Becerril, L.; Bartolini, S.; Sobradelo, R.; Martí, J.; Morales, J. M.; Galindo, I.

    2014-07-01

    Long-term hazard assessment, one of the bastions of risk-mitigation programs, is required for land-use planning and for developing emergency plans. To ensure quality and representative results, long-term volcanic hazard assessment requires several sequential steps to be completed, which include the compilation of geological and volcanological information, the characterisation of past eruptions, spatial and temporal probabilistic studies, and the simulation of different eruptive scenarios. Despite being a densely populated active volcanic region that receives millions of visitors per year, no systematic hazard assessment has ever been conducted on the Canary Islands. In this paper we focus our attention on El Hierro, the youngest of the Canary Islands and the most recently affected by an eruption. We analyse the past eruptive activity to determine the spatial and temporal probability, and likely style of a future eruption on the island, i.e. the where, when and how. By studying the past eruptive behaviour of the island and assuming that future eruptive patterns will be similar, we aim to identify the most likely volcanic scenarios and corresponding hazards, which include lava flows, pyroclastic fallout and pyroclastic density currents (PDCs). Finally, we estimate their probability of occurrence. The end result, through the combination of the most probable scenarios (lava flows, pyroclastic density currents and ashfall), is the first qualitative integrated volcanic hazard map of the island.

  7. 75 FR 52754 - Submission for OMB Review; Comment Request; Assessing the Long-Term Impacts of the John E...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-27

    ... Long- Term Impacts of the John E. Fogarty International Center's Research and Training Programs SUMMARY... Collection: Title: Assessing the Long-Term Impacts of the John E. Fogarty International Center's Research and... Center for the purpose of strengthening biomedical research capacity in low and middle income...

  8. Long-term performance of subsurface-flow constructed wetlands treating Cd wastewater.

    PubMed

    Visesmanee, Varangkana; Polprasert, Chongrak; Parkpian, Preeda

    2008-06-01

    This study was conducted to investigate the long-term performance of subsurface-flow constructed wetland (SFCW) units treating a wastewater containing cadmium (Cd). The hydraulic retention time (HRT) was found to have significant effects on the SFCW performance, especially on Cd removal. During the 320 days of Cd feeding, the HRTs of 1, 3, 5 and 8 days resulted in the Cd removal efficiencies of 50, 90, 99 and 99%, respectively. The actual Cd breakthrough times in the SFCW effluent were found to be longer than the theoretical values calculated from the maximum adsorption capacities only, especially at the HRTs longer than 1 day, and were dependent on the operating HRT and Cd loading. Other mechanisms such as filtration, sedimentation and plant uptake were also responsible for Cd removal in the SFCW beds. The extents of Cd plant uptake were 21 and 6% of the Cd inputs for the SFCW units operating at the HRTs of 3 and 1 days, respectively. Based on Cd mass balance and fractionation analysis, the SFCW media were found to be most effective in Cd removal through adsorption of the residual and Fe/Mn oxide bound fractions. The results of this long-term study re-affirmed the necessity to determine actual breakthrough times of Cd or other heavy metals in the SFCW effluent which are dependent on HRT and Cd loading and are usually longer than the theoretical values calculated from the maximum adsorption capacity only. PMID:18444079

  9. Natural physical and biological processes compromise the long-term performance of compacted soil caps

    SciTech Connect

    Smith, E.D.

    1995-12-01

    Compacted soil barriers are components of essentially all caps placed on closed waste disposal sites. The intended functions of soil barriers in waste facility caps include restricting infiltration of water and release of gases and vapors, either independently or in combination with synthetic membrane barriers, and protecting other manmade or natural barrier components. Review of the performance of installed soil barriers and of natural processes affecting their performance indicates that compacted soil caps may function effectively for relatively short periods (years to decades), but natural physical and biological processes can be expected to cause them to fail in the long term (decades to centuries). This paper addresses natural physical and biological processes that compromise the performance of compacted soil caps and suggests measures that may reduce the adverse consequences of these natural failure mechanisms.

  10. Soil heavy metal dynamics and risk assessment under long-term land use and cultivation conversion.

    PubMed

    Wang, Xuelei; Xu, Yiming

    2015-01-01

    Long-term agricultural development and cultivation conversions affect soil heavy metal balance and the regional environmental safety. In this study, heavy metal parameters were used to identify changes in soil properties in response to land use and cultivation conversions. The integrated soil quality index, which involves seven heavy metal indices, was proposed to assess the environmental risk of long-term human activities in Northeast China. We used the remote sensing and geographical data for the four-term land use distribution from 1979 to 2009 to identify the spatial patterns of regional land use conversions. Then, 41 samples from the top 20 cm of the soil at sites corresponding to these seven types of conversions were collected (permanent dry land, dry land converted from wetland, dry land converted from forest, permanent wetland, permanent forest, paddy land converted from dry land, and paddy land converted from wetland). Based on the local soil properties and tillage practices, the following seven heavy metal parameters were employed: Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb), and Zinc (Zn). The conversion of farmland from wetland resulted in an increase in the concentration of Pb and Cr in the soil. In contrast, the concentrations of Zn, Cu, Ni, and Cd decreased when wetland was converted into farmland because the tillage practices washed these heavy metals away. During the conversion of dry land and paddy land to wetland, the levels of Pb increased by approximately 28.6% and 24.7%, respectively. Under the same conditions, the concentration of As increased by 32.5% and 14.1%, respectively. The integrated index also demonstrated that the farmlands were not contaminated by the heavy metals during long-term agricultural development. PMID:25060313

  11. Effect of modafinil on learning performance and neocortical long-term potentiation in rats.

    PubMed

    Burgos, Héctor; Castillo, Amparo; Flores, Osvaldo; Puentes, Gustavo; Morgan, Carlos; Gatica, Arnaldo; Cofré, Christian; Hernández, Alejandro; Laurido, Claudio; Constandil, Luis

    2010-10-30

    Modafinil is a novel wake-promoting agent whose effects on cognitive performance have begun to be addressed at both preclinical and clinical level. The present study was designed to investigate in rats the effects of chronic modafinil administration on cognitive performance by evaluating: (i) working and reference memories in an Olton 4×4 maze, and (ii) learning of a complex operant conditioning task in a Skinner box. In addition, the effect of modafinil on the ability of the rat frontal cortex to develop long-term potentiation (LTP) was also studied. Chronic modafinil did not significantly modify working memory errors but decreased long-term memory errors on the Olton 4×4 maze, meaning that the drug may have a favourable profile on performance of visuo-spatial tasks (typically, a hippocampus-dependent task) when chronically administered. On the other hand, chronic modafinil resulted in a marked decrease of successful responses in a complex operant conditioning learning, which means that repeated administration of the drug influences negatively problem-solving abilities when confronting the rat to a sequencing task (typically, a prefrontal cortex-dependent task). In addition, in vivo electrophysiology showed that modafinil resulted in impaired capacity of the rat prefrontal cortex to develop LTP following tetanization. It is concluded that modafinil can improve the performance of spatial tasks that depend almost exclusively on hippocampal functioning, but not the performance in tasks including a temporal factor where the prefrontal cortex plays an important role. The fact that modafinil together with preventing operant conditioning learning was also able to block LTP induction in the prefrontal cortex, suggests that the drug could interfere some critical component required for LTP can be developed, thereby altering neuroplastic capabilities of the prefrontal cortex. PMID:20800665

  12. HST/WFC3: new capabilities, improved IR detector calibrations, and long-term performance stability

    NASA Astrophysics Data System (ADS)

    MacKenty, John W.; Baggett, Sylvia M.; Brammer, Gabriel; Hilbert, Bryan; Long, Knox S.; McCullough, Peter; Riess, Adam G.

    2014-08-01

    the causes of its temporal and spatial variation has led to the appreciation of the impact of He I 1.083 micron emission from the earth's atmosphere. This adds a significant and variable background to the two filters and two grisms which include this spectral feature when the HST spacecraft is outside of the earth's shadow. After nearly five years in orbit, long term trending of the scientific and engineering behavior of WFC3 demonstrates excellent stability other than the expected decline in CCD charge transfer efficiency. Addition of post-flash signal to images is shown to markedly improve the transfer efficiency for low level signals. Combined with a pixel based correction algorithm developed at STScl, CCD performance is stabilized at levels only slightly degraded from its initial values.

  13. Evaluating long-term performance of in situ vitrified waste forms: Methodology and results

    SciTech Connect

    McGrail, B.P.; Olson, K.M.

    1992-11-01

    In situ vitrification (ISV) is an emerging technology for the remediation of hazardous and radioactive waste sites. The concept relies on the principle of Joule heating to raise the temperature of a soil between an array of electrodes above the melting temperature. After cooling, the melt solidifies into a massive glass and crystalline block similar to naturally occurring obsidian. Determining the long-term performance of ISV products in a changing regulatory environment requires a fundamental understanding of the mechanisms controlling the dissolution behavior of the material. A series of experiments was performed to determine the dissolution behavior of samples produced from the ISV processing of typical soils from the Idaho National Engineering Laboratory subsurface disposal area. Dissolution rate constant measurements were completed at 90{degrees}C over the pH range 2 to 11 for one sample obtained from a field test of the ISV process.

  14. Evaluating long-term performance of in situ vitrified waste forms: Methodology and results

    SciTech Connect

    McGrail, B.P.; Olson, K.M.

    1992-11-01

    In situ vitrification (ISV) is an emerging technology for the remediation of hazardous and radioactive waste sites. The concept relies on the principle of Joule heating to raise the temperature of a soil between an array of electrodes above the melting temperature. After cooling, the melt solidifies into a massive glass and crystalline block similar to naturally occurring obsidian. Determining the long-term performance of ISV products in a changing regulatory environment requires a fundamental understanding of the mechanisms controlling the dissolution behavior of the material. A series of experiments was performed to determine the dissolution behavior of samples produced from the ISV processing of typical soils from the Idaho National Engineering Laboratory subsurface disposal area. Dissolution rate constant measurements were completed at 90[degrees]C over the pH range 2 to 11 for one sample obtained from a field test of the ISV process.

  15. The Rush to Remediate: Long Term Performance Favors Passive Systems at SRS

    SciTech Connect

    Hoffman, D.; Cauthen, K.; Beul. R. R.

    2003-02-24

    The purpose of this paper is to describe the long-term performance of groundwater remediation systems at SRS and compare active versus passive systems. The presentation will focus on the limited effectiveness of active pump and treat systems and share the experience with more passive and natural systems such as soil vapor extraction, barometric pumping, bioremediation, and phytoremediation. Three remediation projects are presented. In each case the waste source is capped with clay or synthetic barriers; however, extensive groundwater contamination remains. The first project features the cleanup of the largest plume in the United States. The second project entails solvent and vinyl chloride remediation of groundwater beneath a hazardous waste landfill. The third project discusses tritium containment from a 160-acre radioactive waste disposal area. Special emphasis is placed on performance data from alternate technology cleanup. The goals are to share remediation data, successes and lessons learned, while making a case for passive systems use in groundwater remediation.

  16. Long-Term Climate Sensitivity of Grazer Performance: A Cross-Site Study

    PubMed Central

    Craine, Joseph M.

    2013-01-01

    Climate change will affect grasslands in a number of ways, but the consequences of a warmer, drier world for grazers is uncertain. Predicting future grazer performance is complex since climate change affects both the quantity and quality of forage through a combination of processes that occur over a range of time scales. To better predict the consequences of climate change for grazer performance, a dataset was compiled of over a quarter million bison weights distributed across 22 US herds that span a large range of climates. Patterns of bison body mass among sites, age classes, and sexes were analyzed with respect to differences in geographic patterns of climate and interannual variation in climate. While short-term effects of climate variability are likely to depend on the magnitude and timing of precipitation during the year, grazers will be negatively affected by sustained hotter, drier conditions most likely associated with reductions in forage quality. Short-term, little effect of high temperatures on bison performance is observed, which suggests that the long-term effects of higher temperatures are likely to accrue over time as nitrogen availability in grasslands is reduced and forage quality declines. If relationships observed for bison are general for cattle, the economic consequences of higher temperatures due to decreased weight gain in US cattle could be on the order of US$1B per 1°C increase in temperature. Long-term monitoring of forage quality as well as native and domesticated grazer performance is recommended to better understand climate change effects on grazers. PMID:23840584

  17. Long-term ecosystem monitoring and assessment of the Detroit River and Western Lake Erie.

    PubMed

    Hartig, J H; Zarull, M A; Ciborowski, J J H; Gannon, J E; Wilke, E; Norwood, G; Vincent, A N

    2009-11-01

    Over 35 years of US and Canadian pollution prevention and control efforts have led to substantial improvements in environmental quality of the Detroit River and western Lake Erie. However, the available information also shows that much remains to be done. Improvements in environmental quality have resulted in significant ecological recovery, including increasing populations of bald eagles (Haliaeetus leucocephalus), peregrine falcons (Falco columbarius), lake sturgeon (Acipenser fulvescens), lake whitefish (Coregonus clupeaformis), walleye (Sander vitreus), and burrowing mayflies (Hexagenia spp.). Although this recovery is remarkable, many challenges remain, including population growth, transportation expansion, and land use changes; nonpoint source pollution; toxic substances contamination; habitat loss and degradation; introduction of exotic species; and greenhouse gases and global warming. Research/monitoring must be sustained for effective management. Priority research and monitoring needs include: demonstrating and quantifying cause-effect relationships; establishing quantitative endpoints and desired future states; determining cumulative impacts and how indicators relate; improving modeling and prediction; prioritizing geographic areas for protection and restoration; and fostering long-term monitoring for adaptive management. Key management agencies, universities, and environmental and conservation organizations should pool resources and undertake comprehensive and integrative assessments of the health of the Detroit River and western Lake Erie at least every 5 years to practice adaptive management for long-term sustainability. PMID:18850284

  18. Defining Molecular Sensors to Assess Long-Term Effects of Pesticides on Carcinogenesis

    PubMed Central

    L’Héritier, Fanny; Marques, Maud; Fauteux, Myriam; Gaudreau, Luc

    2014-01-01

    The abundance of dioxins and dioxin-like pollutants has massively increased in the environment due to human activity. These chemicals are particularly persistent and accumulate in the food chain, which raises major concerns regarding long-term exposure to human health. Most dioxin-like pollutants activate the aryl hydrocarbon receptor (AhR) transcription factor, which regulates xenobiotic metabolism enzymes that belong to the cytochrome P450 1A family (that includes CYP1A1 and CYP1B1). Importantly, a crosstalk exists between estrogen receptor α (ERα) and AhR. More specifically, ERα represses the expression of the CYP1A1 gene, which encodes an enzyme that converts 17β-estradiol into 2-hydroxyestradiol. However, (ERα) does not repress the CYP1B1 gene, which encodes an enzyme that converts 17β-estradiol into 4-hydroxyestradiol, one of the most genotoxic estrogen metabolites. In this review, we discuss how chronic exposure to xenobiotic chemicals, such as pesticides, might affect the expression of genes regulated by the AhR–ERα crosstalk. Here, we focus on recent advances in the understanding of molecular mechanisms that mediate this crosstalk repression, and particularly on how ERα represses the AhR target gene CYP1A1, and could subsequently promote breast cancer. Finally, we propose that genes implicated in this crosstalk could constitute important biomarkers to assess long-term effects of pesticides on human health. PMID:25257533

  19. Soil quality assessment of urban green space under long-term reclaimed water irrigation.

    PubMed

    Lyu, Sidan; Chen, Weiping

    2016-03-01

    Reclaimed water is widely used for landscape irrigation with the benefits of saving fresh water and ameliorating soil quality. Field samples were collected from seven parks in Beijing irrigated reclaimed water with different irrigation history in 2011 and 2014 to evaluate the long-term impacts of reclaimed water irrigation on soil quality. Soil quality index method was used to assess the comprehensive effects of reclaimed water irrigation on soil. Results showed that the effects of reclaimed water irrigation on the soil nutrient conditions were limited. Compared with tap water irrigation, soil salinity was significantly higher in 2011, while the difference was insignificant in 2014; soil heavy metals were slightly higher by 0.5-10.6 % in 2011 and 2014, while the differences were insignificant. Under reclaimed water irrigation, soil biological activities were significantly improved in both years. Total nitrogen in reclaimed water had a largest effect on soil quality irrigated reclaimed water. Soil quality irrigated with reclaimed water increased by 2.6 and 6.8 % respectively in 2011 and 2014, while the increases were insignificant. Soil quality of almost half samples was more than or closed to soil quality of natural forest in Beijing. Soil quality was ameliorated at some extent with long-term reclaimed water irrigation. PMID:26527339

  20. Defining molecular sensors to assess long-term effects of pesticides on carcinogenesis.

    PubMed

    L'Héritier, Fanny; Marques, Maud; Fauteux, Myriam; Gaudreau, Luc

    2014-01-01

    The abundance of dioxins and dioxin-like pollutants has massively increased in the environment due to human activity. These chemicals are particularly persistent and accumulate in the food chain, which raises major concerns regarding long-term exposure to human health. Most dioxin-like pollutants activate the aryl hydrocarbon receptor (AhR) transcription factor, which regulates xenobiotic metabolism enzymes that belong to the cytochrome P450 1A family (that includes CYP1A1 and CYP1B1). Importantly, a crosstalk exists between estrogen receptor α (ERα) and AhR. More specifically, ERα represses the expression of the CYP1A1 gene, which encodes an enzyme that converts 17β-estradiol into 2-hydroxyestradiol. However, (ERα) does not repress the CYP1B1 gene, which encodes an enzyme that converts 17β-estradiol into 4-hydroxyestradiol, one of the most genotoxic estrogen metabolites. In this review, we discuss how chronic exposure to xenobiotic chemicals, such as pesticides, might affect the expression of genes regulated by the AhR-ERα crosstalk. Here, we focus on recent advances in the understanding of molecular mechanisms that mediate this crosstalk repression, and particularly on how ERα represses the AhR target gene CYP1A1, and could subsequently promote breast cancer. Finally, we propose that genes implicated in this crosstalk could constitute important biomarkers to assess long-term effects of pesticides on human health. PMID:25257533

  1. An Assessment of State-Led Reform of Long-Term Services and Supports.

    PubMed

    Naylor, Mary D; Kurtzman, Ellen T; Miller, Edward Alan; Nadash, Pamela; Fitzgerald, Peter

    2015-06-01

    Health care in the United States is fragmented, inefficient, and rife with quality concerns. These shortcomings have particularly serious implications for adults with disabilities and functionally impaired older adults in need of long-term services and supports (LTSS). Three strategies have been commonly pursued by state governments to improve LTSS: expanding noninstitutional care, integrating payment and care delivery, and realigning incentives through market-based reforms. These strategies were analyzed using an evaluation framework consisting of the following dimensions: ease of access; choice of setting/provider; quality of care/life; support for family caregivers; effective transitions among multiple providers and across settings; reductions in racial/ethnic disparities; cost-effectiveness; political feasibility; and implementability. Although the analysis highlights potential benefits and drawbacks associated with each strategy, the limited breadth of the evidentiary base precludes an assessment of impact across all nine dimensions. More importantly, the analysis exposes the interdependent, complex system of care within which LTSS is situated, suggesting that policy makers will require a holistic and long-term perspective to achieve needed changes. Addressing the nation's LTSS needs will require a multipronged strategy incorporating a range of health and social services to meet the complex care needs of a diverse population in a variety of settings. PMID:25700376

  2. Is Veteran Status and Suicide Risk Assessed in Community Long-Term Care? A Review of the States' Assessment Instruments

    ERIC Educational Resources Information Center

    Matthieu, Monica M.; Welch, Benjamin; Morrow-Howell, Nancy; Proctor, Enola; Nickel, Michael; Navarro, Jessica; Moon, Alyson

    2010-01-01

    Given recent policy initiatives to address suicide risk among older persons and veterans, community-based elder serving agencies may serve an important role in identifying and referring individuals at risk for suicide. A review of state-level long-term assessment instruments was conducted to determine whether veteran status and suicide are…

  3. Long-Term Performance of the Riata/ST Implantable Cardioverter-Defibrillator Lead.

    PubMed

    Ströker, Erwin; de Asmundis, Carlo; Vanduynhoven, Philippe; De Vadder, Katrien; De Vusser, Philip; Mullens, Wilfried; Chierchia, Gian-Battista; Brugada, Pedro; Czapla, Jens; La Meir, Mark; Wellens, Francis; Van Herendael, Hugo; Rivero-Ayerza, Maximo

    2016-03-01

    Riata and Riata ST implantable cardioverter-defibrillator leads are prone to structural and electrical failure (EF). Our objective was to evaluate Riata/ST lead performance over a long-term follow-up. Of 184 patients having undergone Riata/ST and Riata ST Optim lead implantation from September 2003 to June 2008, 154 patients were evaluated for EF and radiographic conductor externalization (CE). Survival analysis for EF was performed for Riata/ST leads, both for failure-free lead survival and cumulative hazard. Subanalysis on 7Fr leads was performed to evaluate EF and CE rates both for different Riata ST lead management (monitoring vs proactive) and between Riata ST and Riata ST Optim leads. During a mean follow-up of 7 years, Riata/ST lead EF rate was 13% overall. Similar failure-free survival rate was noted for 7Fr as for 8Fr leads (log-rank, p = 0.63). Of all failed leads, 64% failed only after 5 years of follow-up. Compared with the absolute failure rate of 1.84% per device year, cumulative hazard analysis for leads surviving past 5 years revealed an estimated failure rate of 7% per year. No clinical or procedural predictors for EF were found. The subanalysis on 7Fr leads showed an excellent outcome both for a proactive lead management approach as for Optim leads. In conclusion, long-term survival of the Riata/ST lead is impaired with an accelerating EF risk over time. An initial exponential trend was followed by a linear lead failure pattern for leads surviving past 5 years, corresponding to an estimated 7% annual EF rate. These findings may have repercussions on the lead management strategy in patients currently surviving with a Riata/ST lead to prevent significant clinical events like inappropriate shocks or failed device interventions. PMID:26762730

  4. Age at treatment and long-term performance results in medulloblastoma

    SciTech Connect

    Chin, H.W.; Maruyama, Y.

    1984-05-01

    Medulloblastoma is highly radioresponsive, and recent treatment results have improved greatly since the introduction of megavoltage machine in 1960s. There is increasing evidence for the potential cure of medulloblastoma if properly treated in its early stages. The curable group represents approximately 75% of diagnosed patients. Long-term treatment effects were examined in this study. The study reveals age-dependent late effects in learning ability; the patients less than 4-years-old at treatment had major learning problems; patients of 5 to 7 years old performed at satisfactory-to-low passing levels in school work; patients older than 8 years old had no major intellectual impairment. Short stature was common when growth potential was present at the time of therapy, but endocrine tests were generally negative. These observations indicate special educational requirement needs, especially for children treated at a young age.

  5. The Performance and Long Term Stability of the D0 Run II Forward Muon Scintillation Counters

    SciTech Connect

    Bezzubov, V.; Denisov, D.; Evdokimov, V.; Lipaev, V.; Shchukin, A.; Vasilyev, I.

    2014-07-21

    The performance of the D0 experiment forward muon scintillation counters system during Run II of the Tevatron from 2001 to 2011 is described. The system consists of 4214 scintillation counters in six layers. The long term stability of the counters amplitude response determined using LED calibration system and muons produced in proton-antiproton collisions is presented. The average signal amplitude for counters of all layers has gradually decreased over ten years by 11%. The reference timing, determined using LED calibration, was stable within 0.26 ns. Average value of muon timing peak position was used for periodic D0 clock signal adjustments to compensate seasonal drift caused by temperature variations. Counters occupancy for different triggers in physics data collection runs and for minimum bias triggers are presented. The single muon yields versus time and the luminosity dependence of yields were stable for the forward muon system within 1% over 10 years.

  6. Long-term assessment of prostaglandin analogs and timolol fixed combinations vs prostaglandin analogs monotherapy

    PubMed Central

    Liu, Ai-Wei; Gan, Lin-Yang; Yao, Xiang; Zhou, Jian

    2016-01-01

    AIM To draw a Meta-analysis over the comparison of the intraocular pressure (IOP)-lowering efficacy and safety between the commonly used fixed-combinations of prostaglandin analogs and 0.5% timolol with prostaglandin analogs (PGAs) monotherapy. METHODS After searching the published reports from MEDLINE, EMBASE, the Cochrane Library, all randomized controlled clinical trials (RCTs) comparing the fixed combination of PGAs/timolol therapy (FCs) and PGAs monotherapy with treatment duration at least 6mo were included. The efficacy outcomes were mean diurnal IOP, percentage of participants whose IOP were lower than 18 mm Hg, incidence of visual field change, while the safety outcomes included corneal side effects, hyperemia and eye irritation. The analysis was carried out in RevMan version 5.3 software. RESULTS After six-month medical intervention, the mean diurnal IOP of FCs was lower than PGAs (MD -1.14, 95% CI -1.82 to -0.46, P=0.001); the percentage of target IOP achieving between FCs and PGAs showed no significant difference (RR 1.18, 95% CI 0.97 to 1.43, P=0.10). No statistically significant differences of the incidence of hyperemia (RR 0.67, 95% CI 0.45 to 1.01, P=0.06) and eye irritation (RR 1.20, 95% CI 0.95 to 1.51, P=0.12) between the FCs and PGAs monotherapy were detected. Only one research involved in corneal events, result of this trial revealed no difference between two intervention groups regarding corneal effects (central endothelial cell density, MD -0.20, 95% CI -0.72 to 0.32, P=0.45; central corneal thickness, MD -0.01, 95% CI -0.02 to 0.00, P=0.23). The evaluation of visual field change was not performed due to the limited duration of the trials included in this Meta-analysis. CONCLUSION The long-term efficacy of the FCs overweighed the PGAs monotherapy in lowering IOP, but in the incidence of hyperemia and eye irritation syndromes, the differences are not statically significant. More RCTs with detailed and authentic data over the assessments of

  7. Assessment of the NASA EVOLVE long-term orbital debris evolution model

    NASA Astrophysics Data System (ADS)

    Yates, K. W.; Jonas, F. M.

    1995-02-01

    The EVOLVE long-term orbital debris evolution model developed for the NASA Johnson Space Center by Lockheed Engineering and Sciences Company and Systems Planning Corporation is described and evaluated in detail. This computer model calculates the low earth orbit (LEO) debris spatial number density or flux environment as a function of fragment size, altitude, and time. Launched intact objects, introduced from detailed manifest databases, are time-evolved with an analytical orbit propagator. Debris clouds, formed from the application of a cloud formation algorithm and breakup model, are time-evolved using a derived phenomenological function. This report describes the overall computer model (e.g., its deterministic and stochastic modes of calculation) and examines the individual submodels used to quantify the debris population in LEO. Model results are compared to observed debris data. Specific recommendations and possible model improvements are cited. Also presented is a sample satellite constellation hazard assessment using EVOLVE.

  8. Long-term assessment of No Evidence of Disease Activity with natalizumab in relapsing multiple sclerosis.

    PubMed

    Prosperini, Luca; Fanelli, Fulvia; Pozzilli, Carlo

    2016-05-15

    In this study we assessed the proportion of patients with relapsing multiple sclerosis (R-MS) who had No Evidence of Disease Activity (NEDA-3), defined as absence of relapses, absence of confirmed disability worsening, and absence of radiological activity (detected by magnetic resonance imaging of the brain and spinal cord) up to 7years after starting natalizumab. Out of 152 patients considered, 58 were still on treatment and 94 discontinued treatment after a median time of 3years. According to an intention-to-treat approach, 52 (34%) patients maintained the NEDA status at the end of follow-up. The proportion of patients with NEDA increases to 41% after excluding from the analysis 64 patients who discontinued natalizumab due to concerns about progressive multifocal leukoencephalopathy. Our findings suggest that natalizumab may ensure higher proportion of patients achieving sustained long-term disease remission than that previously reported with self-injectable treatments (<10%). PMID:27084235

  9. Assessment of long-term impact of formal certified cardiopulmonary resuscitation training program among nurses

    PubMed Central

    Saramma, P. P.; Raj, L. Suja; Dash, P. K.; Sarma, P. S.

    2016-01-01

    Context: Cardiopulmonary resuscitation (CPR) and emergency cardiovascular care guidelines are periodically renewed and published by the American Heart Association. Formal training programs are conducted based on these guidelines. Despite widespread training CPR is often poorly performed. Hospital educators spend a significant amount of time and money in training health professionals and maintaining basic life support (BLS) and advanced cardiac life support (ACLS) skills among them. However, very little data are available in the literature highlighting the long-term impact of these training. Aims: To evaluate the impact of formal certified CPR training program on the knowledge and skill of CPR among nurses, to identify self-reported outcomes of attempted CPR and training needs of nurses. Setting and Design: Tertiary care hospital, Prospective, repeated-measures design. Subjects and Methods: A series of certified BLS and ACLS training programs were conducted during 2010 and 2011. Written and practical performance tests were done. Final testing was undertaken 3–4 years after training. The sample included all available, willing CPR certified nurses and experience matched CPR noncertified nurses. Statistical Analysis Used: SPSS for Windows version 21.0. Results: The majority of the 206 nurses (93 CPR certified and 113 noncertified) were females. There was a statistically significant increase in mean knowledge level and overall performance before and after the formal certified CPR training program (P = 0.000). However, the mean knowledge scores were equivalent among the CPR certified and noncertified nurses, although the certified nurses scored a higher mean score (P = 0.140). Conclusions: Formal certified CPR training program increases CPR knowledge and skill. However, significant long-term effects could not be found. There is a need for regular and periodic recertification. PMID:27303137

  10. [Effects of long term mental arithmetic on physiological parameters, subjective indices and task performances].

    PubMed

    Yamada, Shimpei; Miyake, Shinji

    2007-03-01

    This study examined the effects of long term mental arithmetic on physiological parameters, subjective indices and task performances to investigate the psychophysiological changes induced by mental tasks. Fifteen male university students performed six successive trials of a ten-minute mental arithmetic task. They took a five-minute resting period before and after the tasks. CFF (Critical Flicker Fusion frequency) and subjective fatigue scores using a visual analog scale, POMS (Profiles of Mood States) and SFF (Subjective Feelings of Fatigue) were obtained after each task and resting period. The voices of participants who were instructed to speak five Japanese vowels ('a', 'i', 'u', 'e', 'o') were recorded after each block to investigate a chaotic property of vocal signals that is reported to be changed by fatigue. Subjective workload ratings were also obtained by the NASA-TLX (National Aeronautics and Space Administration-Task Load Index) after the task. Physiological signals of ECG (Electrocardiogram), PTG (Photoelectric Plethysmogram), SCL (Skin Conductance Level), TBV (Tissue Blood Volume) and Respiration were recorded for all experimental blocks. The number of answers, correct rates and average levels of task difficulty for each ten-minute task were used as task performance indices. In this experiment, the task performance did not decrease, whereas subjective fatigue increased. Activation of the sympathetic nervous system was suggested by physiological parameters. PMID:17380727

  11. Long-term performance evaluation of wood fibre fills. Final report

    SciTech Connect

    Kilian, A.P.; Ferry, C.D.

    1992-08-01

    The paper presents the results of a research project to determine the long-term performance of wood fiber embankments, that were constructed by the Washington State Department of Transportation (WSDOT) beginning in 1972. At the time of their construction, concern existed that wood fiber fills would only provide a 15 to 20 year service life. Performance of existing wood fiber fills was evaluated based on the quality of the wood fiber material, quality of the effluent, and condition of the pavement. A visual classification system rating the wood fiber from fresh to completely decomposed was developed and used in order to establish a criteria from which all wood fiber material could be rated. Visual examination in conjunction with laboratory tests were used as determining aspects for the effluent quality. The WSDOT Pavement Management System was used to evaluate relative pavement performance. Site descriptions are presented giving specific characteristics and properties of the fills inventoried. An analysis of this information was done to determine the effectiveness of the fills. Over half the wood fiber samples were found to be nearly fresh or fresh and none were found to be completely decomposed. In all but one case, the pavement quality over the wood fiber fills surpassed the comparative highway segment rating indicating the wood fill's performance exceeded that of the surrounding area.

  12. Long-term air pollution indicator assessment: example of black smoke in Bordeaux, France.

    PubMed

    Filleul, Laurent; Baldi, Isabelle; Quenel, Philippe; Brochard, Patrick; Tessier, Jean François

    2002-05-01

    The aim of the second phase of the Pollution Atmosphérique et Affections Respiratoires Chroniques (PAARC) study, started in 1974, was to compare the long-term mortality between populations living in areas with different air pollution levels. In Bordeaux (France), four different areas were concerned by the study. The black smoke measures were realized between 1974 and 1981. After 1981, the stations set specifically for the study were not used any more. The purpose of this study was to estimate the evolution of air pollution in those areas between 1982 and 1997 using the measures of 12 Association de Prévention de la Pollution Atmosphérique (APPA) stations located in Bordeaux city but not in the PAARC areas. The method used was divided in three phases: a correlation study between the stations of the different networks, a selection of the pertinent stations and the setting up of indicators using the arithmetic means method. Monthly means concentrations were estimated from January 1982 to December 1997. Models showed a decrease in black smoke levels whatever the area. The difference in level from one area to another, existing between the areas in 1974, was still with predicted values in 1997, but less important. Black smoke mean concentration for 1982-1997 was, respectively, 16.4 and 16.2 microg/m3, in areas 1 and 2. It was a little bit higher in area 3 with 18.9 microg/m3. Area 4 still has the highest level with 26.3 microg/m3. To conclude, this method enabled to assess different air pollution levels at different times in the four areas of the PAARC study in Bordeaux. Those levels could be used to study the impact of the air pollution on long-term mortality on populations living in the areas considered. PMID:12032819

  13. Long-term effects of prior cocaine exposure on Morris water maze performance.

    PubMed

    Mendez, Ian A; Montgomery, Karienn S; LaSarge, Candi L; Simon, Nicholas W; Bizon, Jennifer L; Setlow, Barry

    2008-02-01

    Cocaine addiction is associated with long-term cognitive alterations including deficits on tests of declarative/spatial learning and memory. To determine the extent to which cocaine exposure plays a causative role in these deficits, adult male Long-Evans rats were given daily injections of cocaine (30 mg/kg/day x 14 days) or saline vehicle. Three months later, rats were trained for 6 sessions on a Morris water maze protocol adapted from Gallagher, Burwell, and Burchinal [Gallagher, M., Burwell, R., & Burchinal, M. (1993). Severity of spatial learning impairment in aging: development of a learning index for performance in the Morris water maze. Behavioral Neuroscience, 107, 618-626]. Rats given prior cocaine exposure performed similarly to controls on training trials, but searched farther from the platform location on probe trials interpolated throughout the training sessions and showed increased thigmotaxis. The results demonstrate that a regimen of cocaine exposure can impair Morris water maze performance as long as 3 months after exposure. Although the impairments were not consistent with major deficits in spatial learning and memory, they may have resulted from cocaine-induced increases in stress responsiveness and/or anxiety. Increased stress and anxiety would be expected to increase thigmotaxis as well as cause impairments in searching for the platform location, possibly through actions on ventral striatal dopamine signaling. PMID:17904876

  14. Long-term effects of colostrum intake in piglet mortality and performance.

    PubMed

    Declerck, I; Dewulf, J; Sarrazin, S; Maes, D

    2016-04-01

    The present study investigated the long-term effects of colostrum intake on performance and mortality in pigs. A total of 1,455 live-born piglets in 10 commercial herds were followed from birth until 22 wk of age. Pigs were individually weighed at birth, at weaning, at onset (intermediate weight), and during the fattening period (finishing weight). Colostrum intake was calculated by the mechanistic model developed by Theil et al. (see text for citation). One linear mixed model was fitted to model the possible associations between colostrum intake and weight at the weaning, intermediate, and finishing periods. In addition to colostrum intake as the main predictor of interest, other predictor variables were also tested, namely birth weight, birth order, sex, breed, and the interval between birth and first suckling (t). Colostrum intake and birth weight were positively associated with weaning ( < 0.001), intermediate ( < 0.001), and finishing ( < 0.001) weights. Furthermore, higher colostrum intake is more beneficial to weaning ( < 0.001), intermediate ( < 0.001), and finishing ( = 0.02) weights in piglets with low versus high birth weights. Birth order was positively associated with weight at each measurement time ( = 0.01). Sex affected only finishing weight ( < 0.001). Some breeds differed in piglets' weight at onset or during the fattening period. The association between t and weaning weight differed by breed. Three generalized linear mixed models were performed to model the probability of dying during the suckling, the nursery, or the fattening period. Colostrum intake, birth weight, birth order, sex, breed, and t were tested. Preweaning mortality was negatively associated with colostrum intake ( < 0.001) and birth weight ( = 0.004) and positively associated with t ( < 0.001). Mortality during the nursery period was negatively associated with colostrum intake ( < 0.001) and birth weight ( = 0.002). The negative association between colostrum intake and mortality

  15. Long-term lessons on pesticide leaching obtained via the Danish Pesticide Leaching Assessment Programme

    NASA Astrophysics Data System (ADS)

    Rosenbom, A. E.; Olsen, P.; Plauborg, F.; Grant, R.; Juhler, R. K.; Brüsch, W.; Kjær, J.

    2014-12-01

    To avoid any unacceptable influence on the environment posed by pesticides and their degradation products, all pesticides used in the European Union needs authorization. The authorization procedure includes assessing the leaching risk of both pesticides and their degradation products to the groundwater. There are shortcomings to the procedure, however, as revealed by the results of the Danish Pesticide Leaching Assessment Programme from the period 1990/2000 to 2012 (app. twelve years). This monitoring program has for this period assessed leaching into groundwater via the variably-saturated zone of 43 pesticides applied in accordance with current regulations on sandy and loamy agricultural fields, and 47 of their degradation products. Three types of leaching scenario were not fully captured by the authorization procedure: i) long-term leaching of degradation products of pesticides applied on potato crops cultivated in sandy soils, ii) leaching of strongly sorbing pesticides after autumn application on loamy soils, and iii) leaching of various pesticides and their degradation products following early summer application on loamy soils. The monitoring data revealed that the authorization procedure was unable to predict leaching scenarios for a number of pesticides in hydrogeological settings dominated by rapid preferential transport via e.g. biopores that bypasses the retardation (sorption and degradation) of the plow layer. Such settings are primarily present in the autumn, but can also occur during the early summer in connection with the formation of a structural seal on the soil surface.

  16. China's Building Energy Use: A Long-Term Perspective based on a Detailed Assessment

    SciTech Connect

    Eom, Jiyong; Clarke, Leon E.; Kim, Son H.; Kyle, G. Page; Patel, Pralit L.

    2012-01-13

    We present here a detailed, service-based model of China's building energy use, nested in the GCAM (Global Change Assessment Model) integrated assessment framework. Using the model, we explore long-term pathways of China's building energy use and identify opportunities of reducing greenhouse gas emissions. The inclusion of a structural model of building energy demands within an integrated assessment framework represents a major methodological advance. It allows for a structural understanding of the drivers of building energy consumption while simultaneously considering the other human and natural system interactions that influence changes in the global energy system and climate. We also explore a range of different scenarios to gain insights into how China's building sector might evolve and what the implications might be for improved building energy technology and carbon policies. The analysis suggests that China's building energy growth will not wane anytime soon, although technology improvement will put downward pressure on this growth. Also, regardless of the scenarios represented, the growth will involve the continued, rapid electrification of the buildings sector throughout the century, and this transition will be accelerated by the implementation of carbon policy.

  17. Long-term performance of the steel-cement interface in CO2 sequestration wells

    NASA Astrophysics Data System (ADS)

    Carey, J. W.; Han, J.

    2011-12-01

    Long-term performance of CO2 storage reservoirs will require that wells (injection, monitoring, and pre-existing) continue to provide isolation of the buoyant CO2 plume. Short-term leakage concerns are driven by the quality of the well completions, particularly placement of Portland cement. However, operational and CO2-injection induced stresses in the reservoir may introduce small defects in the well isolation system, allowing migration of small quantities of CO2 and brine. Evidence for such leaks has been observed in a CO2-enhanced oil recovery well (Carey et al. 2007) and in a natural CO2 reservoir (Crow et al. 2010). The key question in long-term performance is whether these leaks will grow as wellbore materials degrade or whether carbonate precipitation reactions will self-heal the defects. In this study, we focus on the interface between steel casing and Portland cement. In a properly completed well, Portland cement provides a protective, alkaline environment for carbon steel that precludes the possibility of external corrosion. The protective cement can be damaged either by the formation of small gaps at the interface, known as microannuli, or by the carbonation of cement which eliminates cement alkalinity. To investigate these issues, we conducted experiments on cement-steel composites at conditions ranging from atmospheric to high-pressure to determine the susceptibility of steel to corrosion in the presence of well-bonded cement, carbonated cement, and cement separated from the steel by varying gap distances. The presence of cement greatly reduces corrosion rates of steel because an iron carbonate scale forms rapidly and provides a mass-transfer barrier. Similarly, a small gap at the cement-steel interface provides a mass-transfer barrier. Our results show that scale formation provides a more significant barrier to corrosion and that even small gaps (<100 um) do not enhance protection in the cement-steel system. For steel embedded in cement, corrosion

  18. A Performance Analysis of Long-term Acute-Care Hospitals Owned by Large, Multistate Investor-Owned Companies.

    PubMed

    Nayar, Preethy; Liu, Xinliang; McCue, Michael J

    2016-01-01

    This study provides a descriptive assessment of the operating performance of for-profit long-term acute-care hospitals owned by multistate, investor-owned companies (large FP LTCHs) compared with FP LTCHs owned by smaller FP companies (small FP LTCHs) and nonprofit LTCHs (NP LTCHs). The study used the Centers for Medicare & Medicaid Services cost report data for 290 LTCHs from 2010 through 2012 to compare the financial performance of large and small FP LTCHs and NP LTCHs. The study found that the median operating profit margin for large FP LTCHs was 8.06%, which was twice as high as that of the small FP LTCHs and NP LTCHs (4.78% and 2.80%, respectively). Larger size, serving a greater proportion of private pay and more complex patients and incurring lower operating expenses, including salary expenses, may account for the higher operating margin of the large FP LTCHs. PMID:27111686

  19. Influence of different mesh filter module configurations on effluent quality and long-term filtration performance.

    PubMed

    Loderer, Christian; Wörle, Anna; Fuchs, Werner

    2012-04-01

    Recently, a new type of wastewater treatment system became the focus of scientific research: the mesh filter activated sludge system. It is a modification of the membrane bioreactor (MBR), in which a membrane filtration process serves for sludge separation. The main difference is that a mesh filter is used instead of the membrane. The effluent is not of the same excellent quality as with membrane bioreactors due to the much lager pore sizes of the mesh. Nevertheless, it still resembles the quality of currently used standard treatment system, the activated sludge process. The new process shows high future potential as an alternative where a small footprint of these plants is required (3 times lower footprint than conventional activated sludge systems because of neglecting the secondary clarifier and reducing the biological stage). However, so far only limited information on this innovative process is available. In this study, the effect of different pore sizes and different mesh module configurations on the effluent quality was investigated varying the parameters cross-flow velocity (CFV) and flux rate. Furthermore the long-term filtration performance was studied in a pilot reactor system and results were compared to the full-scale conventional activated sludge process established at the same site. The results demonstrate that the configuration of the filter module has little impact on effluent quality and is only of importance with regard to engineering aspects. Most important for a successful operation are the hydrodynamic conditions within the filter module. The statement "the higher the pore size the higher the effluent turbidity" was verified. Excellent effluent quality with suspended solids between 5 and 15 mg L(-1) and high biological elimination rates (chemical oxygen demand (COD) 90-95%, biological oxygen demand (BOD5) 94-98%, total nitrogen (TN) 70-80%, and ammonium nitrogen (NH(4)-N) 95-99%) were achieved and also compared to those of conventional

  20. Long-term performance of the VISIR/VLT instrument before the upgrade

    NASA Astrophysics Data System (ADS)

    Dobrzycka, Danuta; Momany, Yazan; Lundin, Lars; Siebenmorgen, Ralf; Käufl, Hans U.; Smette, Alain; Kerber, Florian; Van Den Ancker, Mario

    2012-09-01

    The ESO's VLT Spectrometer and Imager for the Mid-Infrared (VISIR) has been in operation at the Paranal Observatory since 2005. It is equipped with two DRS (formerly Boeing) 256 × 256 BIB arrays. The project to replace detectors into new Raytheon, 1k × 1k AQUARIUS devices as well as to modify observing modes, software, etc. is underway. The VISIR upgrade creates a well defined break point in the instruments' characteristics. For nearly 7 years of the VISIR operations we have been collecting and processing calibration data, in particular observations of the imaging and spectroscopic standard stars, within a regular data flow operation scheme. The derived quality control parameters have been systematically written into a database, which allows the analysis of their temporal behavior. We present an overview of the long term variations of the VISIR quality control parameters: sensitivity, conversion factor and mean background level estimations. The results will be later used to compare performance of VISIR before and after the upgrade.

  1. Construction and performance of a long-term earthen liner experiment

    USGS Publications Warehouse

    Cartwright, Keros; Krapac, Ivan G.

    1990-01-01

    In land burial schemes, compacted soil barriers with low hydraulic conductivity are commonly used in cover and liner systems to control the movement of liquids and prevent groundwater contamination. An experimental liner measuring 8 x 15 x 0.9 m was constructed with design criteria and equipment to simulate construction of soil liners built at waste disposal facilities. The surface of the liner was flooded with a 29.5 cm deep pond on April 12, 1988. Infiltration of water into the liner has been monitored for two years using 4 large-ring (1.5 m OD) and 32 small-ring (0.28 m OD) infiltrometers, and a water-balance that accounts for total infiltration and evaporation. Average long-term infiltration fluxes based on two years of monitoring are 5.8 x 10-9 cm/s, 6.0 x 10-8 cm/s and 5.6 x 10-8 for the large-ring, small-ring, and water-balance data, respectively. The saturated hydraulic conductivity of the liner based on small-ring data, estimated using Darcy's Law and the Green-Ampt Approximation, is 3 x 10-8 and 4 x 10-8 cm/s, respectively. All sets of data indicate that the liner's performance exceed that which is required by the U.S. EPA.

  2. Long-term dinoflagellate culture performance in a commercial photobioreactor: Amphidinium carterae case.

    PubMed

    Fuentes-Grünewald, C; Bayliss, C; Fonlut, F; Chapuli, E

    2016-10-01

    The aim of this work was to study the culture performance of a dinoflagellate in a commercial photobioreactor. The results obtained during this long-term experiment allow to confirm that Amphidinium carterae is a promising dinoflagellate that can be exploited successfully in closed systems, in semi-continuous mode in indoor and outdoor environments. The average results in an indoor 5cm light-path 320L photobioreactor were, in terms of specific growth rate (0.29d(-1)), duplication time (3.1d(-1)) and dry biomass productivity (78mgL(-1)d(-1)). Specific compounds production was found including ω3 and ω6 fatty acids and, pigments (Peridinin, β-carotene). These promising results, besides unique characteristics found during the exploitation period such as resistance to mechanical stress, self-control of contaminant organisms, and quick cells aggregation when the culture is not in turbulence conditions, makes A. carterae one of the new target species suitable for commercially exploitation on an industrial scale. PMID:27395001

  3. A Long-Term Performance Enhancement Method for FOG-Based Measurement While Drilling.

    PubMed

    Zhang, Chunxi; Lin, Tie

    2016-01-01

    In the oil industry, the measurement-while-drilling (MWD) systems are usually used to provide the real-time position and orientation of the bottom hole assembly (BHA) during drilling. However, the present MWD systems based on magnetic surveying technology can barely ensure good performance because of magnetic interference phenomena. In this paper, a MWD surveying system based on a fiber optic gyroscope (FOG) was developed to replace the magnetic surveying system. To accommodate the size of the downhole drilling conditions, a new design method is adopted. In order to realize long-term and high position precision and orientation surveying, an integrated surveying algorithm is proposed based on inertial navigation system (INS) and drilling features. In addition, the FOG-based MWD error model is built and the drilling features are analyzed. The state-space system model and the observation updates model of the Kalman filter are built. To validate the availability and utility of the algorithm, the semi-physical simulation is conducted under laboratory conditions. The results comparison with the traditional algorithms show that the errors were suppressed and the measurement precision of the proposed algorithm is better than the traditional ones. In addition, the proposed method uses a lot less time than the zero velocity update (ZUPT) method. PMID:27483270

  4. A long-term, continuous simulation approach for large-scale flood risk assessments

    NASA Astrophysics Data System (ADS)

    Falter, Daniela; Schröter, Kai; Viet Dung, Nguyen; Vorogushyn, Sergiy; Hundecha, Yeshewatesfa; Kreibich, Heidi; Apel, Heiko; Merz, Bruno

    2014-05-01

    The Regional Flood Model (RFM) is a process based model cascade developed for flood risk assessments of large-scale basins. RFM consists of four model parts: the rainfall-runoff model SWIM, a 1D channel routing model, a 2D hinterland inundation model and the flood loss estimation model for residential buildings FLEMOps+r. The model cascade was recently undertaken a proof-of-concept study at the Elbe catchment (Germany) to demonstrate that flood risk assessments, based on a continuous simulation approach, including rainfall-runoff, hydrodynamic and damage estimation models, are feasible for large catchments. The results of this study indicated that uncertainties are significant, especially for hydrodynamic simulations. This was basically a consequence of low data quality and disregarding dike breaches. Therefore, RFM was applied with a refined hydraulic model setup for the Elbe tributary Mulde. The study area Mulde catchment comprises about 6,000 km2 and 380 river-km. The inclusion of more reliable information on overbank cross-sections and dikes considerably improved the results. For the application of RFM for flood risk assessments, long-term climate input data is needed to drive the model chain. This model input was provided by a multi-site, multi-variate weather generator that produces sets of synthetic meteorological data reproducing the current climate statistics. The data set comprises 100 realizations of 100 years of meteorological data. With the proposed continuous simulation approach of RFM, we simulated a virtual period of 10,000 years covering the entire flood risk chain including hydrological, 1D/2D hydrodynamic and flood damage estimation models. This provided a record of around 2.000 inundation events affecting the study area with spatially detailed information on inundation depths and damage to residential buildings on a resolution of 100 m. This serves as basis for a spatially consistent, flood risk assessment for the Mulde catchment presented in

  5. Comparative test of ecological assessment methods of lowland streams based on long-term monitoring data of macrophytes.

    PubMed

    Wiegleb, Gerhard; Gebler, Daniel; van de Weyer, Klaus; Birk, Sebastian

    2016-01-15

    Ecological assessment of water courses is required by the European Water Framework Directive (WFD). Assessment by means of macrophytes is impeded by insufficient knowledge on the relations between assessment scores and the dynamics of environmental parameters. Data from a long-term observation of macrophyte dynamics over 21 years in two lowland rivers were used for testing the performance of six widely used assessment methods. Six sample sites situated in two lowland streams were selected. Four sites were classified as of moderate habitat quality and two sites as of poor habitat quality in the context of WFD. Assessment methods generally showed a poor performance in recognizing the ecological status of the annual observations. Status was more often over- than underestimated. Performance of methods differed among individual rivers and among river zones. Assessment scores mostly showed a steady decline, even though all sites obviously remained in the same habitat quality class throughout the observation period. Variation of most environmental factors was largely unrelated to assessment scores. Fluctuations of assessment scores were partly related to single natural disturbance events such as high discharge. Increased shading by marginal trees was reflected negatively by most assessment scores. Assessment scores were highly correlated with species richness and total abundance. The best overall performance was shown by the North-Rhine Westphalian (NRW) method. In contrast to single metric methods it can be adapted to individual properties of a reach in a flexible way. Macrophyte assessment based on the pressure-impact framework did not lead to a satisfying result in our case study. Improvement of species assessment scores and inclusion of functional properties such as growth form may help to overcome the present difficulties. PMID:26476066

  6. Assessing long-term impacts of increased crop productivity on atmospheric CO2.

    PubMed

    Cavazzoni, J; Volk, T

    1996-05-01

    A full assessment of the impacts of land clearance and crop production on atmospheric CO2 requires a systems approach. By considering long-term soil carbon changes and fossil fuel energy inputs, we show that increased crop productivity will alleviate CO2 release to the atmosphere primarily by preventing additional land cultivation. Each hectare of cropland undergoing a simulated threefold crop productivity increase here prevents a net release on the order of 150-200 Mg C to the atmosphere over 100 years by avoiding additional land cultivation which would otherwise be required. This effective carbon sink would slowly diminish with time due to fossil fuel energy input requirements. However, future self-containment of the energy needs of high-yield crop production may displace on the order of 1.0 Pg C per year of fossil fuel carbon, in addition to the carbon sink attributable to avoided land cultivation. By avoiding land cultivation, high yield crop systems also preserve natural ecosystems. PMID:11539330

  7. Heat Transport and Long-Term Change in the Southern Ocean: Assessing the Role of Eddies

    NASA Astrophysics Data System (ADS)

    Gwiazda, R.; Paull, C. K.; Dallimore, S.; Melling, H.; Jin, Y. K.

    2014-12-01

    Long-term change in the Southern Ocean can be difficult to evaluate because of both the paucity of historic observations and the magnitude of eddy variability. The low stratification of the Southern Ocean means that eddies detected by altimetry at the ocean surface extend through the top 2 km of the ocean. Sea surface height anomalies are more strongly correlated with sub-surface variability at depths between about 600 and 1400 dbars than they are with variability in the upper 200 dbars. Altimetric variability can thus be used to remove eddy-related anomalies from individual Argo profiles, resulting in a smoother estimate of mean temperature and salinity. This "eddy-free" mean field serves as a benchmark against which to assess decadal-scale changes in the Southern Ocean, and we use historic hydrographic data to evaluate temperature and salinity changes through the second half of the 20th century. We also evaluate the behavior of Southern Ocean eddies themselves: Although in most parts of the ocean closed oceanic eddies appear to result in thermally indirect heat transport, eddies that are carried eastward by the ACC tend to propagate in the opposite direction, resulting in thermally direct, poleward heat transport across the ACC. Evidence suggests that this cell is maintained by the effective eastward propagation of eddies relative to the mean flow at deep levels.

  8. A long-term, integrated impact assessment of alternative building energy code scenarios in China

    SciTech Connect

    Yu, Sha; Eom, Jiyong; Evans, Meredydd; Clarke, Leon E.

    2014-04-01

    China is the second largest building energy user in the world, ranking first and third in residential and commercial energy consumption. Beginning in the early 1980s, the Chinese government has developed a variety of building energy codes to improve building energy efficiency and reduce total energy demand. This paper studies the impact of building energy codes on energy use and CO2 emissions by using a detailed building energy model that represents four distinct climate zones each with three building types, nested in a long-term integrated assessment framework GCAM. An advanced building stock module, coupled with the building energy model, is developed to reflect the characteristics of future building stock and its interaction with the development of building energy codes in China. This paper also evaluates the impacts of building codes on building energy demand in the presence of economy-wide carbon policy. We find that building energy codes would reduce Chinese building energy use by 13% - 22% depending on building code scenarios, with a similar effect preserved even under the carbon policy. The impact of building energy codes shows regional and sectoral variation due to regionally differentiated responses of heating and cooling services to shell efficiency improvement.

  9. Assessment of auditory evoked potential in long-term mobile phone users.

    PubMed

    Sevi, E Chandra; Kumar, P Sai; Mariam, Yasmin

    2014-01-01

    Mobile phones emit strong electromagnetic wave which causes structural and functional changes in the cell membrane within the central nervous system especially auditory system. The effect of duration of mobile phone use on auditory function was examined One hundred and seventy three long-term mobile phone users aged around 17-39 yrs (both male and female) were recruited in this study. The subjects were divided into three groups according to their age Group I (17-19 yrs), Group II (20-29 yrs), Group III (30-39 yrs). After getting informed consent the subjects were instructed to fill the questionnaire for the history related to our study, conduction deafness auditory brainstem response in both the ears were assessed. Significant difference was observed among three groups in their duration of mobile phone use. Latency of Waves in three groups showed significant difference. The average latency (both right and left ear) of waves I-V was found to be prolonged in Group II when compared to Group I and Group III. Interpeak latencies I-V and I-III showed differences among three groups. The findings of present study showed abnormalities in the conduction of electrical signals in different levels of auditory pathway. PMID:26215013

  10. Assessment of the usefulness of semipermeable membrane devices for long-term watershed monitoring in an urban slough system

    USGS Publications Warehouse

    McCarthy, K.

    2006-01-01

    Semipermeable membrane devices (SPMDs) were deployed at eight sites within the Buffalo Slough, near Portland, Oregon, to (1) measure the spatial and seasonal distribution of dissolved polycyclic aromatic hydrocarbon (PAH) and organochlorine (OC) compounds in the slough, (2) assess the usefulness of SPMDs as a tool for investigating and monitoring hydrophobic compounds throughout the Columbia Slough system, and (3) evaluate the utility of SPMDs as a tool for measuring the long-term effects of watershed improvement activities. Data from the SPMDs revealed clear spatial and seasonal differences in water quality within the slough and indicate that for hydrophobic compounds, this time-integrated passive-sampling technique is a useful tool for long-term watershed monitoring. In addition, the data suggest that a spiking rate of 2-5 ??g/SPMD of permeability/performance reference compounds, including at least one compound that is not susceptible to photodegradation, may be optimum for the conditions encountered here. ?? Springer Science + Business Media, Inc. 2006.

  11. PROJECTED IMPACT OF SULFATE ATTACK ON THE LONG-TERM PERFORMANCE OF A CONCRETE REPOSITORY

    SciTech Connect

    Flach, G.

    2009-12-11

    Saltstone is a cementitious waste form made by mixing salt solution originating from liquid waste storage tanks at the DOE Savannah River Site with a dry mix containing blast furnace slag, fly ash, and cement or lime. The wet mix is poured into a concrete repository for on-site disposal. Solidified Saltstone is a dense, alkaline, reducing, micro-porous, monolithic, cementitious matrix, containing a solution of salts within its pore structure. Sodium sulfate concentrations in the pore fluid are around 0.15 mol/L, and external sulfate attack on concrete barriers is expected to occur over time. To predict the long-term performance of concrete repositories, the STADIUM{reg_sign} code was used to simulate the reactive transport processes leading to formation of ettringite, an expansive mineral phase often associated with spalling or cracking. STADIUM{reg_sign} is a multi-ionic transport model based on a split operator approach that separates ionic movement and chemical reactions. Ionic transport is described by the extended Nernst-Planck equation for unsaturated media, and accounts for electrical coupling between ionic species, chemical activity, transport due to water content gradient, and temperature effects. STADIUM{reg_sign} does not predict whether physical damage will occur, or the impact on transport properties should fracturing occur. Thus the presence of ettringite was assumed to coincide with physical damage for the purpose of estimating effective transport properties. Effective properties for concrete barriers were estimated assuming complete hydraulic failure behind the ettringite front and unaltered properties ahead of the front. The ettringite front advances at a rate dependent on the diffusion coefficient assumed for the failed zone. A sensitivity study indicates a service life ranging from thousands to tens of thousands of years, depending on the barrier thickness and sulfate exposure conditions among other factors.

  12. Development, operation, and long-term performance of a full-scale biocurtain utilizing bioaugmentation.

    PubMed

    Dybas, Michael J; Hyndman, David W; Heine, Robert; Tiedje, James; Linning, Katrina; Wiggert, David; Voice, Thomas; Zhao, Xianda; Dybas, Leslie; Criddle, Craig S

    2002-08-15

    A full-scale field evaluation of bioaugmentation was conducted in a carbon tetrachloride (CT)- and nitrate-impacted aquifer at Schoolcraft, MI. The added organism was Pseudomonas stutzeri KC (strain KC), a denitrifying bacterium that cometabolically degrades CT without producing chloroform (CF). To introduce and maintain strain KC in the aquifer, a row of closely spaced (1-m) injection/extraction wells were installed normal to the direction of groundwater flow near the leading edge of the CT plume. The resulting system of wells was used to establish and maintain a "biocurtain" for CT degradation through the intermittent addition of base to create favorable pH conditions; inoculation; and weekly addition of acetate (electron donor), alkali, and phosphorus. Although half of the test zone was inoculated twice, the long-term performance of both sections was indistinguishable: both had high CT removal efficiencies (median of 98-99.9%) and similar levels of strain KC colonization (>10(5) strain KC/g). Sustained and efficient (98%) removal of CT has now been observed over 4 yr. Transient low levels of CF (<20 ppb) and H2S (<2 ppm) were observed, but both disappeared when the concentration of acetate in the weekly feed was reduced. Nitrate removal efficiencies ranged from 60% at low acetate concentrations to nearly 100% at high acetate concentrations. We conclude that closely spaced wells and intermittent substrate addition are effective means of delivering organisms and substrates to subsurface environments. At the Schoolcraft site, we achieved uniform removal efficiencies over a significant vertical depth (15 m), despite significant variability in hydraulic conductivity. This was accomplished by pumping 65% (v/v) of the natural gradient flow passing through the biocurtain during a given week in a single 6-h pumping event. Approximately 18,600 m3 of contaminated groundwater was treated during the project. PMID:12214659

  13. Nursing Assistants for Long-Term Care. Performance-Based Instructional Materials.

    ERIC Educational Resources Information Center

    Indiana Univ., Bloomington. Vocational Education Services.

    This guide is intended to assist students enrolled in programs to train nursing assistants for employment in an Indiana long-term health care facility. The first part discusses human development (growth, aging, and dying); communication with residents; sexuality; legal, ethical, and professional responsibilities of nursing assistants in long-term…

  14. PERFORMANCE OF ORGANIC GRAIN CROPPING SYSTEMS IN LONG-TERM EXPERIMENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic farming and conventional no-tillage farming systems share many of the same benefits from protecting and improving soils. A review of recent results from long-term systems experiments in the mid-Atlantic region of the U.S.A. demonstrates that organic cropping systems with organic amendments ...

  15. Long-term Radiation Budget Variability in the Northern Eurasian Region: Assessing the Interaction with Fire

    NASA Astrophysics Data System (ADS)

    Stackhouse, P. W.; Soja, A. J.; Zhang, T.; Mikovitz, J. C.

    2013-12-01

    In terms of global change, boreal regions are particularly important, because significant warming and change are already evident and significant future warming is predicted. Mean global air temperature has increased by 0.74°C in the last century, and temperatures are predicted to increase by 1.8°C to 4°C by 2090, depending on the Inter-governmental Panel on Climate Change (IPCC) scenario. Some of the greatest temperature increases are currently found in the Northern Eurasian winter and spring, which has led to longer growing seasons, increased potential evapotranspiration and extreme fire weather [Groisman et al., 2007]. In the Siberian Sayan, winter temperatures have already exceeded a 2090 Hadley Centre scenario (HadCM3GGa1) [Soja et al., 2007]. There is evidence of climate-induced change across the circumboreal in terms of increased infestations, alterations in vegetation and increased fire regimes (area burned, fire frequency, severity and number of extreme fire seasons). In this paper, we analyzed long-term surface radiation data sets from the NASA/GEWEX (Global Energy and Water Exchanges) Surface Radiation Budget data products, CERES Surface EBAF and SYN data products and also the available surface radiation measurements in the region. First, we show that during overlap years SRB and CERES data products agree very well in terms of anomalies and we'll use this fact to evaluate 30 years of satellite based estimates of the variability of downwelling SW parameters first corresponding to locations of surface measurements and then for the region as a whole. We also show the observed variability of other SW components such as the net SW and the albedo. Next we assess the variability of the downward and LW fluxes over time and compare these to variability observed in the surface temperature and other meteorological measurements. We assess anomalies on various spatial scales. Finally, we assess the correlation of this variability in specific locations to known fire

  16. Strategy for identifying natural analogs of the long-term performance of low-level waste disposal sites

    SciTech Connect

    Chatters, J.C.; Waugh, W.J.; Foley, M.G.; Kincaid, C.T.

    1990-07-01

    The US Department of Energy's Low-Level Waste (LLW) Management Program has asked Pacific Northwest Laboratory (PNL) to explore the feasibility of using natural analogs of anticipated waste site and conditions to help validate predictions of the performance of LLW disposal sites. Current regulations require LLW facilities to control the spread of hazardous substances into the environment for at least the next 500 years. Natural analog studies can provide information about processes affecting waste containment that cannot be fully explored through laboratory experimentation and modeling because of the extended period of required performance. For LLW applications, natural analogs include geochemical systems, pedogenic (soil formation) indicators, proxy climate data, and ecological and archaeological settings that portray long-term changes in disposal site environments and the survivability of proposed waste containment materials and structures. Analog data consist of estimates of performance assessment (PA) model input parameters that define possible future environmental states of waste sites, validation parameters that can be predicted by PA models, and descriptive information that can build public confidence in waste disposal practices. This document describes PNL's overall stategy for identifying analogs for LLW disposal systems, reviews lessons learned from past analogs work, outlines the findings of the workshop, and presents examples of analog studies that workshop participants found to be applicable to LLW performance assessment. The lessons from the high-level waste analogs experience and workshop discussions will be used to develop detailed study plans during FY 1990. 39 refs.

  17. Assessing the Long Term Impact of Phosphorus Fertilization on Phosphorus Loadings Using AnnAGNPS

    PubMed Central

    Yuan, Yongping; Bingner, Ronald L.; Locke, Martin A.; Stafford, Jim; Theurer, Fred D.

    2011-01-01

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss and evaluate the effects of different phosphorus fertilization rates on phosphorus losses, the USDA Annualized AGricultural Non-Point Source (AnnAGNPS) pollutant loading model was applied to the Ohio Upper Auglaize watershed, located in the southern portion of the Maumee River Basin. In this study, the AnnAGNPS model was calibrated using USGS monitored data; and then the effects of different phosphorus fertilization rates on phosphorus loadings were assessed. It was found that P loadings increase as fertilization rate increases, and long term higher P application would lead to much higher P loadings to the watershed outlet. The P loadings to the watershed outlet have a dramatic change after some time with higher P application rate. This dramatic change of P loading to the watershed outlet indicates that a “critical point” may exist in the soil at which soil P loss to water changes dramatically. Simulations with different initial soil P contents showed that the higher the initial soil P content is, the less time it takes to reach the “critical point” where P loadings to the watershed outlet increases dramatically. More research needs to be done to understand the processes involved in the transfer of P between the various stable, active and labile states in the soil to ensure that the model simulations are accurate. This finding may be useful in setting up future P application and management guidelines. PMID:21776225

  18. Long Term Prospective Assessment of Living Kidney Donors: Single Center Experience

    PubMed Central

    Nagib, Ayman Maher; Refaie, Ayman Fathi; Hendy, Yasser Abdelmoniem; Elfawal, Magdy Abass Mohmed; Shokeir, Ahmed Abdelrahman; Bakr, Mohamed Adel; Neamattala, Ahmed Hassan; Hamdy, Ahmed Farouk; Mahmoud, Khaled Mohamed; Ismail, Amani Mostafa; Ghoneim, Mohamed Ahmed

    2014-01-01

    Virtually, all studies reporting the outcomes of living kidney donation beyond the first year from donation were retrospective. In this prospective study, the outcome of 81 consecutive living kidney donors was thoroughly evaluated. Clinical, laboratory, and radiological assessments were carried out at predonation (basal), 3, 6, 12, and 24 months after donation. The mean age at time of donation was 37.8 ± 9.8 years and the majority was females (75.3%). The mean BMI increased significantly after donation (P < 0.04). The mean serum creatinine levels (mg/dl) were 0.75 ± 0.14, 1.01 ± 0.22, 0.99 ± 0.21, 0.98 ± 0.20, and 0.94 ± 0.20 (P < 0.0001). Likewise, the mean levels of measured creatinine clearance (mL/min) were 148.8 ± 35.7, 94.7 ± 26.6, 95.5 ± 24.6, 96.7 ± 20.2, and 101.6 ± 26.2 (P < 0.0001). The mean 24 hours urinary protein excretion (gm/dL) were 0.09 ± 0.03, 0.19 ± 0.18, 0.16 ± 0.09, 0.18 ± 0.25, and 0.17 ± 0.12 (P < 0.0001). There were significant increases in the means of the longitudinal and transverse diameters of the remaining kidney over time (P < 0.001). Out of 42 female donors, eleven female donors have got successful postdonation pregnancies. There were no reported surgical complications, either intra- or postoperative. Long-term follow-up is necessary for all living kidney donors through local institutional and world registries. This trial is registered with ClinicalTrials.gov NCT00813579. PMID:24967244

  19. Long-Term Slip History Discriminates Among Occurrence Models for Seismic Hazard Assessment

    NASA Astrophysics Data System (ADS)

    Fitzenz, D. D.; Ferry, M. A.; Jalobeanu, A.

    2010-12-01

    Today, the probabilistic seismic hazard assessment (PSHA) community relies on one or a combination of stochastic models to compute occurrence probabilities for large earthquakes. Considerable efforts have been devoted to extracting the maximum information from long catalogues of large earthquakes (CLE) based on instrumental, historical, archeological and paleoseismological data (Biasi et al, 2009, Parsons, 2008, Rhoades and Dissen 2003). However, the models remain only and insufficiently constrained by these rare single-slip event data. Therefore, the selection of the models and their respective weights is necessarily left with the appreciation of a panel of experts (WGCEP, 2003). Since cumulative slip data with high temporal and spatial resolution are now available, we propose here a new approach to incorporate these pieces of evidence of mid- to long-term fault behavior into the next generation of PSHA: the Cumulative Offset-Based Bayesian Recurrence Analysis (COBBRA). Applied to the Jordan Valley segment of the Dead Sea Fault, the method yields the best combination of occurrence models for full-segment ruptures knowing the available single-event and cumulative data. Not only does our method provide data-driven, objective weights to the competing models, but it also allows to rule out time-independence, and to compute the cumulative probability of occurrence for the next full-segment event reflecting all available data. References: Biasi, G. P. & Weldon, R. J., II. Bull. Seism. Soc. Am. 99, 471-498, doi:10.1785/0120080287 (2009). Parsons, T. J. Geophys. Res., 113, doi:10.1029/2007JB004,998.216 (2008) Rhoades, D. A., and R. J. V. Dissen, New Zealand Journal of Geology & Geophysics, 46, 479-488 (2003). Working Group On California Earthquake Probabilities. Earthquake Probabilities in the San Francisco Bay Region: 2002-2031. (2003).

  20. Hematopoietic effects of benzene inhalation assessed by long-term bone marrow culture

    SciTech Connect

    Abraham, N.G.

    1996-12-01

    The strong and long-lasting hematotoxic effect after benzene exposure in vivo (300 ppm, 6 hr/day, 5 days/week for 2 weeks) was assessed in mice with bone marrow cells grown in long-term bone marrow culture (LTBMC). Bone marrow cultures initiated 1 day after the last benzene exposure did not produce adequate numbers of hematopoietic cells over 3 weeks and, in most cases, no erythroid or myeloid clonogenic cells could be recovered. The adherent cell layer of these cultures had a lower capacity for supporting in vitro hematopoiesis after the second seeding with normal bone marrow cells compared with control cultures. Two weeks after the last benzene exposure, body weight, hematocrit, bone marrow cellularity, and committed hematopoietic progenitor content (BFU-E and CFU-GM) were regenerated to normal or subnormal values, whereas hematopoiesis in LTB MC was very poor. Over 8 weeks, little or no significant committed progenitor production was observed. Treatment of mice exposed to benzene with hemin (three doses of 3 {mu}g/g bw iv over 2 weeks for a total dose of 9 {mu}g/g) partially overcame the toxic effect of benzene on the hematopoietic system as measured by the LTBMC method. Cultures from mice treated with hemin had a modest recovery of BFU-E and CFU-GM clonogenic potential after 5 to 6 weeks in LTBMC. In contrast, little or no recovery was obtained for the adherent cell layer clonogenic capacity, even after hemin treatment. These results clearly indicate a strong, long-lasting toxic effect on the bone marrow stroma and a limited recovery of hematopoietic potential by clonogenic cells of the nonadherent population after in vivo hemin treatment. 35 refs., 3 figs., 1 tab.

  1. Assessing the long term impact of phosphorus fertilization on phosphorus loadings using AnnAGNPS.

    PubMed

    Yuan, Yongping; Bingner, Ronald L; Locke, Martin A; Stafford, Jim; Theurer, Fred D

    2011-06-01

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss and evaluate the effects of different phosphorus fertilization rates on phosphorus losses, the USDA Annualized AGricultural Non-Point Source (AnnAGNPS) pollutant loading model was applied to the Ohio Upper Auglaize watershed, located in the southern portion of the Maumee River Basin. In this study, the AnnAGNPS model was calibrated using USGS monitored data; and then the effects of different phosphorus fertilization rates on phosphorus loadings were assessed. It was found that P loadings increase as fertilization rate increases, and long term higher P application would lead to much higher P loadings to the watershed outlet. The P loadings to the watershed outlet have a dramatic change after some time with higher P application rate. This dramatic change of P loading to the watershed outlet indicates that a "critical point" may exist in the soil at which soil P loss to water changes dramatically. Simulations with different initial soil P contents showed that the higher the initial soil P content is, the less time it takes to reach the "critical point" where P loadings to the watershed outlet increases dramatically. More research needs to be done to understand the processes involved in the transfer of P between the various stable, active and labile states in the soil to ensure that the model simulations are accurate. This finding may be useful in setting up future P application and management guidelines. PMID:21776225

  2. NAEP 1999 Long-Term Trend Technical Analysis Report: Three Decades of Student Performance. NCES 2005-484

    ERIC Educational Resources Information Center

    Allen, Nancy L.; McClellan, Catherine A.; Stoeckel, Joan J.

    2005-01-01

    This report provides an update to the technical analysis procedures documenting the 1996 National Assessment of Educational Progress (NAEP) as presented in "The NAEP 1996 Technical Report" (Allen, Carlson, and Zelenak, 1999). It describes how the 1999 long-term trend data were incorporated into the trend analyses. Since no national main or state…

  3. Assessment of long-term channel changes in the Mekong River using remote sensing and a channel-evolution model

    NASA Astrophysics Data System (ADS)

    Miyazawa, N.

    2011-12-01

    River-channel changes are a key factor affecting physical, ecological and management issues in the fluvial environment. In this study, long-term channel changes in the Mekong River were assessed using remote sensing and a channel-evolution model. A channel-evolution model for calculating long-term channel changes of a measndering river was developed using a previous fluid-dynamic model [Zolezzi and Seminara, 2001], and was applied in order to quantify channel changes of two meandering reaches in the Mekong River. Quite few attempts have been made so far to combine remote sensing observation of meandering planform change with the application of channel evolution models within relatively small-scale gravel-bed systems in humid temperate regions. The novel point of the present work is to link state-of-art meandering planform evolution model with observed morphological changes within large-scale sand-bed rivers with higher bank height in tropical monsoonal climate regions, which are the highly dynamic system, and assess the performance. Unstable extents of the reaches could be historically identified using remote-sensing technique. The instability caused i) bank erosion and accretion of meander bends and ii) movement or development of bars and changes in the flow around the bars. The remote sensing measurements indicate that maximum erosion occurred downstream of the maximum curvature of the river-center line in both reaches. The model simulations indicates that under the mean annual peak discharge the maximum of excess longitudinal velocity near the banks occurs downstream of the maximum curvature in both reaches. The channel migration coefficients of the reaches were calibrated by comparing remote-sensing measurements and model simulations. The diffrence in the migration coefficients between both reaches depends on the diffrence in bank height rather than the geotechnical properties of floodplain sediments. Possible eroded floodplain areas and accreted floodplain

  4. Assessing the impact of long-term cultivation on runoff, pollutant load, and crop yields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past century, agriculture had detrimental impacts on soil and water quality revealed by increased surface runoff and non-point source pollution. In this study, we estimated the impact of long-term agriculture on surface runoff, sediment yield, atrazine load, and crop yields. Soil samples we...

  5. The Long-Term Learning Agreement: A New Assessment Tool for Educators.

    ERIC Educational Resources Information Center

    Venditti, Phillip N.

    Long-term learning agreements are compacts between faculty members and students that permit students to "borrow" a grade and then pay to keep it by carrying out specified supplementary activities during an extended period after an academic term ends. These agreements can combat grade inflation, reinforce students' self-confidence, allow…

  6. ANNUAL REPORT. CORROSION OF SPENT NUCLEAR FUEL: THE LONG-TERM ASSESSMENT

    EPA Science Inventory

    This proposal is based on the study of uraninite and the naturally occurring alteration products of UO2+x under oxidizing and reducing conditions. This scientific program will address the following issues:
    1) What are the long-term corrosion products of natural UO2+x under red...

  7. Assessing the Long-Term Impact of a Metacognitive Approach to Creative Skill Development

    ERIC Educational Resources Information Center

    Hargrove, Ryan A.

    2013-01-01

    The goal of this research was to determine the long-term impact that selected instructional interventions, based on research in metacognition and learning theory, have on students' creativity. The study builds off research that has been conducted documenting the impact of creative thinking based instructional interventions. The study tracked…

  8. The Effect of Frequent Quizzes on Short- and Long-Term Academic Performance.

    ERIC Educational Resources Information Center

    Geist, James R.; Soehren, Stephen E.

    1997-01-01

    This study examined effects of frequent quizzes on dental student performance in a course on introductory radiology. Results indicated the group (N=36) with frequent quizzes performed significantly better than the control group (n=35) on midterm and final examinations (but not post-tests), and assessed course content and instructor more…

  9. DEVELOPMENT OF A LONG-TERM MONITORING SYSTEM TO EVALUATE COVER SYSTEM PERFORMANCE

    SciTech Connect

    Kumthekar, U.; Chiou, J. D.; Prochaska, M.; Benson, C. H.

    2002-02-25

    Environmental remediation at the Fernald Environmental Management Project is nearing completion, but long-term technology needs continue to emerge at the site. Remote, real-time, autonomous monitoring technologies are needed to ensure the integrity of the site and its remedy systems once cleanup is complete. The Fernald Post Closure Stewardship Technology Project (PCSTP), through the work of the Integrating Stewardship Technology Team (ISTT), has selected technologies to address initial site needs. This paper will explore the monitoring requirements of the Fernald On-Site Disposal Facility (OSDF), the parameters selected as critical for comprehensive long-term monitoring of the facility, and the process by which technologies were chosen to monitor those parameters.

  10. Long-term multi-hazard assessment for El Misti volcano (Peru)

    NASA Astrophysics Data System (ADS)

    Sandri, Laura; Thouret, Jean-Claude; Constantinescu, Robert; Biass, Sébastien; Tonini, Roberto

    2014-02-01

    We propose a long-term probabilistic multi-hazard assessment for El Misti Volcano, a composite cone located <20 km from Arequipa. The second largest Peruvian city is a rapidly expanding economic centre and is classified by UNESCO as World Heritage. We apply the Bayesian Event Tree code for Volcanic Hazard (BET_VH) to produce probabilistic hazard maps for the predominant volcanic phenomena that may affect c.900,000 people living around the volcano. The methodology accounts for the natural variability displayed by volcanoes in their eruptive behaviour, such as different types/sizes of eruptions and possible vent locations. For this purpose, we treat probabilistically several model runs for some of the main hazardous phenomena (lahars, pyroclastic density currents (PDCs), tephra fall and ballistic ejecta) and data from past eruptions at El Misti (tephra fall, PDCs and lahars) and at other volcanoes (PDCs). The hazard maps, although neglecting possible interactions among phenomena or cascade effects, have been produced with a homogeneous method and refer to a common time window of 1 year. The probability maps reveal that only the north and east suburbs of Arequipa are exposed to all volcanic threats except for ballistic ejecta, which are limited to the uninhabited but touristic summit cone. The probability for pyroclastic density currents reaching recently expanding urban areas and the city along ravines is around 0.05 %/year, similar to the probability obtained for roof-critical tephra loading during the rainy season. Lahars represent by far the most probable threat (around 10 %/year) because at least four radial drainage channels can convey them approximately 20 km away from the volcano across the entire city area in heavy rain episodes, even without eruption. The Río Chili Valley represents the major concern to city safety owing to the probable cascading effect of combined threats: PDCs and rockslides, dammed lake break-outs and subsequent lahars or floods

  11. Comparison of Landsat MSS and TM imagery for long term forest land cover change assessment

    NASA Astrophysics Data System (ADS)

    Genc, Levent

    2003-10-01

    The main objective of this research is to determine forest cover change from 1975 to 2000 for a region in north Florida. In order to monitor long-term forest cover change for this project, Landsat MSS must be used with Landsat TM because Landsat MSS is the only datasets that is available for civilian use prior to the year of 1982. However, using these two different datasets in a project had been problematic and needed to be studied to obtain higher overall classification accuracy. Landsat MSS and TM classifications were achieved through a common approach. By increasing overall accuracy for both sensor types individually, images from these sensors will be more consistent. In order to achieve the main objective of this study, sixteen derived datasets were constructed and tested from March 24, 1986 Landsat MSS and Landsat TM imagery from the same area using low pass filtering, principal component Analysis (PCA), and tasseled cap transformation (TCT) to demonstrate the relationship between these two imageries. Similarities were 88.5% in best case. Results suggest that smoothing operations performed prior to classification improved the classification accuracy because they created a selection of homogeneous training sets. It was found that the smoothing operation performed prior to classification improved the classification accuracy by 7% compared to the original dataset classification. Performing the PCA and TCT to smoothed datasets also improved the classification accuracy by 4% compared to the smoothed datasets only. The first two principal components, PC1 and PC2, added to the first two indexes from TCT, BI and GI, were used to create new 4-band datasets for MSS and TM. These combinations of images were used to determine the forest land cover for the application site from the years 1975 to 2000. It was found that the determination of five land cover classes using these techniques produced moderate overall land cover classification accuracy ranging from 62.7% to 88

  12. Development of testing and analysis methodology to assess the long term durability of polymeric composites at high temperatures

    NASA Technical Reports Server (NTRS)

    Johnson, W. Steven

    1990-01-01

    A workshop was held to help assess the state-of-the-art in evaluating the long term durability of polymeric matrix composites (PMCs) and to recommend future activities. Design and evaluation of PMCs at elevated temperatures were discussed. The workshop presentations, the findings of the workshop sessions are briefly summarized.

  13. Echocardiographic Assessment of Ischaemic Mitral Regurgitation, Mechanism, Severity, Impact on Treatment Strategy and Long Term Outcome

    PubMed Central

    Naser, Nabil; Dzubur, Alen; Kusljugic, Zumreta; Kovacevic, Katarina; Kulic, Mehmed; Sokolovic, Sekib; Terzic, Ibrahim; Haxihibeqiri-Karabdic, Ilirijana; Hondo, Zorica; Brdzanovic, Snjezana; Miseljic, Sanja

    2016-01-01

    Introduction: The commonest mitral regurgitation etiologies are degenerative (60%), rheumatic post-inflammatory, 12%) and functional (25%). Due to the large number of patients with acute MI, the incidence of ischaemic MR is also high. Ischaemic mitral regurgitation is a complex multifactorial disease that involves left ventricular geometry, the mitral annulus, and the valvular/subvalvular apparatus. Ischaemic mitral regurgitation is an important consequence of LV remodeling after myocardial infarction. Research Objectives: The objective of this study is to determine the role of echocardiography in detecting and assessment of mitral regurgitation mechanism, severity, impact on treatment strategy and long term outcome in patients with myocardial infarction during the follow up period of 5 years. Also one of objectives to determine if the absence or presence of ischaemic MR is associated with increased morbidity and mortality in patients with myocardial infarction. Patients and methods: The study covered 138 adult patients. All patients were subjected to echocardiography evaluation after acute myocardial infarction during the period of follow up for 5 years. The patients were examined on an ultrasound machine Philips iE 33 xMatrix, Philips HD 11 XE, and GE Vivid 7 equipped with all cardiologic probes for adults and multi-plan TEE probes. We evaluated mechanisms and severity of mitral regurgitation which includes the regurgitant volume (RV), effective regurgitant orifice area (EROA), the regurgitant fraction (RF), Jet/LA area, also we measured the of vena contracta width (VC width cm) for assessment of IMR severity, papillary muscles anatomy and displacement, LV systolic function ± dilation, LV regional wall motion abnormality WMA, LV WMI, Left ventricle LV remodeling, impact on treatment strategy and long term mortality. Results: We analyzed and follow up 138 patients with previous (>16 days) Q-wave myocardial infarction by ECG who underwent TTE and TEE

  14. Long-term follow-up of endoscopic third ventriculostomy performed in the pediatric population.

    PubMed

    Stovell, Matthew G; Zakaria, Rasheed; Ellenbogen, Jonathan R; Gallagher, Mathew J; Jenkinson, Michael D; Hayhurst, Caroline; Mallucci, Conor L

    2016-06-01

    OBJECTIVE Endoscopic third ventriculostomy (ETV) is an effective treatment for obstructive hydrocephalus and avoids the risk for foreign-body infection associated with ventriculoperitoneal (VP) shunts. The short-term failure rate of ETV strongly depends on the indications for its use but is generally thought to be lower in the long term than that of VP shunts. However, few studies are available with long-term follow-up data of ETV for hydrocephalus in children. The authors reviewed the long-term success of ETV at their institution to investigate the rate of any late failures of this procedure. METHODS Between April 1998 and June 2006, 113 children (including neonates and children up to 16 years old) had primary or secondary ETV for different causes of hydrocephalus. The patients' medical records and the authors' electronic operation database were reviewed for evidence of additional surgery (i.e., repeat ETV or VP shunt insertion). These records were checked at both the pediatric and adult neurosurgical hospitals for those patients who had their care transferred to adult services. RESULTS The median length of follow-up was 8.25 years (range 1 month to 16 years). Long-term follow-up data for 96 patients were available, 47 (49%) of whom had additional ETV or VP shunt insertion for ETV failure. Twenty patients (21%) had a second procedure within 1 month, 17 patients (18%) between 1 and 12 months, 7 patients (7%) between 1 and 5 years, and 3 patients (3%) between 5 and 8 years. CONCLUSIONS In the authors' series, ETV had an initial early failure rate for the treatment of pediatric hydrocephalus as reported previously, and this rate significantly depended on patient age and hydrocephalus etiology. Once stabilized and effective, ETV appeared to be durable but not guaranteed, and some late decline in effectiveness was observed, with some ETV failures occurring many years later. Thus, successful ETV in children cannot be guaranteed for life, and some form of follow-up is

  15. The long-term agroecological research (LTAR) experiment supports organic yields, soil quality, and economic performance in Iowa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Long-Term Agroecological Research (LTAR) experiment, at the Iowa State University Neely-Kinyon Farm in Greenfield, Iowa, was established in 1998 to compare the agronomic, ecological and economic performance of conventional and organic cropping systems. The main goals of the project are to evalua...

  16. Long-Term Impact of On-Demand Professional Development on Student Performance: A Longitudinal Multi-State Study

    ERIC Educational Resources Information Center

    Shaha, Steven H.; Glassett, Kelly F.; Ellsworth, Heather

    2015-01-01

    The long-term effects of Professional Development (PD) on educators' ability to affect student performance remain virtually unstudied. This quasi-experimental, longitudinal study compared student achievement scores from 25 states and 78 school districts over multiple years for schools whose teachers used an online, on-demand professional…

  17. LONG-TERM PERFORMANCE OF PERMEABLE REACTIVE BARRIERS USING ZERO-VALENT IRON: GEOCHEMICAL AND MICROBIOLOGICAL EFFECTS

    EPA Science Inventory

    Geochemical and microbiological factors that control long-term performance of subsurface permeable reactive barriers were evaluated at the Elizabeth City, NC and the Denver Federal Center, CO sites. These ground water treatment systems use zero-valent iron filings (Peerless Meta...

  18. A probabilistic assessment of large scale wind power development for long-term energy resource planning

    NASA Astrophysics Data System (ADS)

    Kennedy, Scott Warren

    contribution by synthesizing information from research in power market economics, power system reliability, and environmental impact assessment, to develop a comprehensive methodology for analyzing wind power in the context of long-term energy planning.

  19. Photovoice: Assessing the Long-Term Impact of a Disaster on a Community's Quality of Life.

    PubMed

    Annang, Lucy; Wilson, Sacoby; Tinago, Chiwoneso; Wright Sanders, Louisiana; Bevington, Tina; Carlos, Bethany; Cornelius, Evangeline; Svendsen, Erik

    2016-01-01

    Photovoice is a qualitative method of inquiry whereby individuals can document their lived experiences, particularly individuals whose voices are not typically heard in regard to promoting social change and policy development. We used photovoice to elicit major themes regarding community members' perceptions of the long-term impact on their quality of life as a deadly technological disaster hit a small, rural town in South Carolina. Overall, participants photographed more negative images than positive. Overarching themes included residential and business vacancies, economic decline, the need for clean-up and modernization, attention to wellness or rehabilitation, and concerns for safety. Emergency response agencies should consider the themes elicited from these community residents to help identify where to focus disaster response efforts both in the immediate aftermath and during the long-term recovery period of technological disasters, particularly in underserved, rural communities. PMID:25794525

  20. Assessing long-term health and cost outcomes of patient-centered medical homes serving adults with poor diabetes control.

    PubMed

    Pagán, José A; Carlson, Erin K

    2013-10-01

    The patient-centered medical home (PCMH) is an integrated primary care delivery model particularly suited for patients with poor diabetes control. Although PCMH models targeting adults with diabetes have shown some early success, little is known about the long-term benefits of medical homes in terms of health and cost outcomes. The performance of a PCMH model in adults with poor diabetes control was assessed using simulated controlled trial data obtained from the Archimedes model of disease progression and health care utilization. Using the Cardio-Metabolic Risk data set, we compared health and cost outcomes over a 20-year period between adults with poor diabetes control (HbA1c >9%) receiving standard care and these same adults receiving care under a PCMH model with a 49% HbA1c intervention improvement rate at a per-beneficiary per-month care management cost of $20 per month. The results suggest that the PCMH model has the potential to not only reduce the proportion of the population with bilateral blindness, foot amputations, and myocardial infarctions-and the mortality rate-but it can also do so in a cost-effective manner ($7898 per quality-adjusted life year). The PCMH model is cost saving for the population 50 to 64 years old and it is particularly cost-effective for men ($883 per quality-adjusted life year). Moreover, these effects are relatively large for adults 30 to 49 years old (lower bilateral blindness and death rates), women (lower foot amputation and death rates), and men (lower bilateral blindness and myocardial infarction rates). The PCMH model has potential long-term benefits to both patients with poor diabetes control as well as health care systems and providers willing to invest in this health care delivery approach. PMID:23799676

  1. ByMuR model: interaction among risks and uncertainty treatment in long-term multi-hazard/risk assessments

    NASA Astrophysics Data System (ADS)

    Selva, J.

    2012-12-01

    Multi-risk approaches have been recently proposed to assess and compare different risks in the same target area. The key point of multi-risk assessments are the development of homogeneous risk definitions and the treatment of risk interaction. The lack of treatment of interaction may lead to significant biases and thus to erroneous risk hierarchization, which is one of primary output of risk assessments for decision makers. Within the framework of the Italian project "ByMuR - Bayesian Multi-Risk assessment", a formal model (ByMuR model) to assess multi-risk for a target area is under development, aiming (i) to perform multi-risk analyses treating interaction between different hazardous phenomena, accounting for possible effects of interaction at hazard, vulnerability and exposure levels, and (ii) to explicitly account for all uncertainties (aleatory and epistemic) through a Bayesian approach, allowing a meaningful comparison among different risks. The model is meant to be general, but it is targeted to the assessment of volcanic, seismic and tsunami risks for the city of Naples (Italy). Here, it is presented the preliminary development of the ByMuR model. The applicability of the methodology is demonstrated through illustrative examples, in which the effects of uncertainties and the bias in single-risk estimation induced by the assumption of independence among risks are explicitly assessed. An extensive application of this methodology at regional and sub-regional scale would allow to identify where a given interaction has significant effects in long-term risk assessments, and thus when multi-risk analyses should be considered in order to provide unbiased risk estimations.

  2. Accelerated long-term assessment of thermal and chemical stability of bio-based phase change materials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thermal energy storage (TES) systems incorporated with phase change materials (PCMs) have potential applications to control energy use by building envelopes. However, it is essential to evaluate long term performance of the PCMs and cost effectiveness prior to full scale implementation. For this rea...

  3. Design and performance of an electrical stimulator for long-term contraction of cultured muscle cells.

    PubMed

    Marotta, Mario; Bragós, Ramón; Gómez-Foix, Anna M

    2004-01-01

    Excitability in muscle cells manifests itself as contractility and may be evoked by electrical stimulation. Here we describe an electrical stimulator device applicable to cells seeded on standard multiwell plates and demonstrate how it effectively stimulates synchronous contraction of skeletal muscle C2C12 cells without damaging them. The electrical stimulator of cultured cells (ESCC) consists of two connection cards and a network of platinum electrodes positioned in such way that each well in a row is uniformly stimulated. The ESCC may produce a range of outputs based on the stimulation parameters it receives from a commercial pulse generator and can be placed in a standard cell incubator, allowing for long-term stimulation as required for biochemical and molecular biological assays. We show that a 90-min stimulation of C2C12 myotubes at 50 V, 30 ms of pulse duration, and 3 Hz of frequency enhances glucose metabolism and glycogen mobilization while oppositely modulating the activity ratio of glycogen metabolizing enzymes. Thus, we demonstrate that long-term electrical stimulation of C2C12 myotubes with the ESCC results in contractility and metabolic changes, as seen in exercising muscle. PMID:14740487

  4. Long-Term Impact of Efavirenz on Neuropsychological Performance and Symptoms in HIV-Infected Individuals (ACTG 5097s)

    PubMed Central

    Clifford, David B.; Evans, Scott; Yang, Yijun; Acosta, Edward P.; Ribaudo, Heather; Gulick, Roy M.

    2010-01-01

    Background Efavirenz (EFV) is an antiretroviral (ARV) drug associated with neuropsychological effects. Limited data describing the long-term impact of EFV-based regimens on neuropsychological performance over more than 3 years are available. Methods We enrolled a subset of participants from a large initially EFV placebo-controlled trial of therapies for HIV subjects naïve to ARV treatment (A5095). Clinical follow-up continued for 184 weeks of study. Subjects were assessed with brief neuropsychological testing, a symptom questionnaire of EFV-associated symptoms, the Pittsburgh Sleep Index, Center for Epidemiologic Studies-Depression Scale, and an anxiety rating interview. Results Over 184 weeks on EFV, the median NPZ3 score in 86 evaluable patients improved from baseline by +0.5 (p < .01); all components improved, although higher EFV levels were associated with slightly lower responses. Overall symptom scores did not change, while EFV-associated CNS symptoms increased (p = .01). Median change of bad dream sleep scores and anxiety increased from the baseline while global depression score decreased. Conclusions In participants who continued EFV-based regimens, neuropsychological performance improvement from baseline was maintained over 3 years. EFV-based treatment was generally well tolerated, but small increases from baseline in EFV-associated symptoms, bad dreams, and anxiety were detected. PMID:20133265

  5. Long-Term Assessment of Critical Radionuclides and Associated Environmental Media at the Savannah River Site - 13038

    SciTech Connect

    Jannik, G.T.; Baker, R.A.; Lee, P.L.; Eddy, T.P.; Blount, G.C.; Whitney, G.R.

    2013-07-01

    During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities. However, only a relatively small number of the released radionuclides have been significant contributors to doses and risks to the public. At SRS dose and risk assessments indicate tritium oxide in air and surface water, and Cs-137 in fish and deer have been, and continue to be, the critical radionuclides and pathways. In this assessment, statistical analyses of the long-term trends of tritium oxide in atmospheric and surface water releases and Cs-137 concentrations in fish and deer are provided. Correlations also are provided with 1) operational changes and improvements, 2) geopolitical events (Cold War cessation), and 3) recent environmental remediation projects and decommissioning of excess facilities. For example, environmental remediation of the F- and H-Area Seepage Basins and the Solid Waste Disposal Facility have resulted in a measurable impact on the tritium oxide flux to the onsite Fourmile Branch stream. Airborne releases of tritium oxide have been greatly affected by operational improvements and the end of the Cold War in 1991. However, the effects of SRS environmental remediation activities and ongoing tritium operations on tritium concentrations in the environment are measurable and documented in this assessment. Controlled hunts of deer and feral hogs are conducted at SRS for approximately six weeks each year. Before any harvested animal is released to a hunter, SRS personnel perform a field analysis for Cs-137 concentrations to ensure the Hunter's dose does not exceed the SRS administrative game limit of 0.22 milli-sievert (22 mrem). However, most of the Cs-137 found in SRS onsite deer is not from site operations but is from nuclear weapons testing fallout from the 1950's and early 1960's. This legacy source term is trended in the SRS deer, and an assessment of the 'effective' half-life of Cs-137 in deer (including

  6. Fluorescent multiple staining and CASA system to assess boar sperm viability and membranes integrity in short and long-term extenders

    PubMed Central

    Lange-Consiglio, A.; Meucci, A.; Cremonesi, F.

    2013-01-01

    The aim of this study was to assess the effect on boar spermatozoa quality of in vitro storage in short and long-term extenders by fluorescent multiple staining (FMS) and computer assisted semen analyzer (CASA). Fresh ejaculates from three healthy, sexually mature boars were diluted with equal volumes of six short-term or three long-term commercial extenders and stored at 19°C for 6 days (short-term) or 12 days (long-term). The integrity of spermatozoa membranes was analyzed by FMS using propidium iodide, 5,5’,6,6’-tetrachloro-1,1’,3,3’ tetraethylbenzimidazolyl-carbocyanine iodide (JC-1) and fluorescein isothiocyanate-conjugated peanut agglutinin (PNA). The results obtained from this staining were compared with spermatozoa motility assessed by CASA. Our study showed that the number of viable spermatozoa with non-reacted acrosomes and intact mitochondria was positively correlated with the rate of motile spermatozoa (r2>0.9) irrespective of the extender used. In all extenders the number of motile spermatozoa significantly decreased as preservation period increased (P<0.05). FMS test is a potent indicator of sperm motility because it analyses mitochondrial integrity independently from observable alterations in motility. The best performing extenders were BTS for short-term storage and TRI-x-Cell for long-term storage. PMID:26623308

  7. Assessing Long-Term Wind Conditions by Combining Different Measure-Correlate-Predict Algorithms: Preprint

    SciTech Connect

    Zhang, J.; Chowdhury, S.; Messac, A.; Hodge, B. M.

    2013-08-01

    This paper significantly advances the hybrid measure-correlate-predict (MCP) methodology, enabling it to account for variations of both wind speed and direction. The advanced hybrid MCP method uses the recorded data of multiple reference stations to estimate the long-term wind condition at a target wind plant site. The results show that the accuracy of the hybrid MCP method is highly sensitive to the combination of the individual MCP algorithms and reference stations. It was also found that the best combination of MCP algorithms varies based on the length of the correlation period.

  8. Ozone Data Quality Assessment (O3S-DQA): Resolving inhomogenities due to artifacts in long term ozone sounding records

    NASA Astrophysics Data System (ADS)

    Smit, H. G.; Oltmans, S. J.

    2012-12-01

    Ozone sounding records provide the longest time series of the vertical ozone distribution between the surface and 30-35 km altitude. Up to an altitude of 20 km ozone sondes constitute the single data source with long term coverage for the derivation of ozone trends with sufficient vertical resolution, particularly in the altitude region around the tropopause. JOSIE and BESOS results have clearly demonstrated that even small differences of sensing techniques, sensor types or sensing solutions can introduce significant inhomogenities in the long term sounding records between different sounding stations or within each station individually. To resolve these artifacts sounding records have to be homogenized either in space (between different stations) or in time (long term changes) through use of generic transfer functions which can be derived from intercomparison experiments (e.g. JOSIE or BESOS) and dual balloon soundings. In the context of the on-going SPARC/IGACO-O3/IOC initiative on "Understanding past changes in the vertical distribution of ozone", we started the "Ozone Sonde Data Quality Assessment (O3S-DQA)" activity in 2011 with the primary goal of homogenizing selected ozone sonde data sets to be used for this ozone assessment. We aim to reduce uncertainties between long term sounding records from 10-20% down to 5-10% through the use of generic transfer functions. We will present the methodology, key guide lines for re-processing long term ozone records (including the use of transfer functions) and present the first results of the homogenization process. This will include the quantification of the overall uncertainties of the achieved results which will be focused on the tropospheric profiling capabilities of ozone sondes.

  9. Environmental management: Integrating ecological evaluation, remediation, restoration, natural resource damage assessment and long-term stewardship on contaminated lands

    PubMed Central

    Burger, Joanna

    2014-01-01

    Ecological evaluation is essential for remediation, restoration, and Natural Resource Damage Assessment (NRDA), and forms the basis for many management practices. These include determining status and trends of biological, physical, or chemical/radiological conditions, conducting environmental impact assessments, performing remedial actions should remediation fail, managing ecosystems and wildlife, and assessing the efficacy of remediation, restoration, and long-term stewardship. The objective of this paper is to explore the meanings of these assessments, examine the relationships among them, and suggest methods of integration that will move environmental management forward. While remediation, restoration, and NRDA, among others, are often conducted separately, it is important to integrate them for contaminated land where the risks to ecoreceptors (including humans) can be high, and the potential damage to functioning ecosystems great. Ecological evaluations can range from inventories of local plants and animals, determinations of reproductive success of particular species, levels of contaminants in organisms, kinds and levels of effects, and environmental impact assessments, to very formal ecological risk assessments for a chemical or other stressor. Such evaluations can range from the individual species to populations, communities, ecosystems or the landscape scale. Ecological evaluations serve as the basis for making decisions about the levels and kinds of remediation, the levels and kinds of restoration possible, and the degree and kinds of natural resource injuries that have occurred because of contamination. Many different disciplines are involved in ecological evaluation, including biologists, conservationists, foresters, restoration ecologists, ecological engineers, economists, hydrologist, and geologists. Since ecological evaluation forms the basis for so many different types of environmental management, it seems reasonable to integrate management options

  10. Classification tree for risk assessment in patients suffering from congestive heart failure via long-term heart rate variability.

    PubMed

    Melillo, Paolo; De Luca, Nicola; Bracale, Marcello; Pecchia, Leandro

    2013-05-01

    This study aims to develop an automatic classifier for risk assessment in patients suffering from congestive heart failure (CHF). The proposed classifier separates lower risk patients from higher risk ones, using standard long-term heart rate variability (HRV) measures. Patients are labeled as lower or higher risk according to the New York Heart Association classification (NYHA). A retrospective analysis on two public Holter databases was performed, analyzing the data of 12 patients suffering from mild CHF (NYHA I and II), labeled as lower risk, and 32 suffering from severe CHF (NYHA III and IV), labeled as higher risk. Only patients with a fraction of total heartbeats intervals (RR) classified as normal-to-normal (NN) intervals (NN/RR) higher than 80% were selected as eligible in order to have a satisfactory signal quality. Classification and regression tree (CART) was employed to develop the classifiers. A total of 30 higher risk and 11 lower risk patients were included in the analysis. The proposed classification trees achieved a sensitivity and a specificity rate of 93.3% and 63.6%, respectively, in identifying higher risk patients. Finally, the rules obtained by CART are comprehensible and consistent with the consensus showed by previous studies that depressed HRV is a useful tool for risk assessment in patients suffering from CHF. PMID:24592473

  11. Using the Nursing Culture Assessment Tool (NCAT) in Long-Term Care: An Update on Psychometrics and Scoring Standardization

    PubMed Central

    Kennerly, Susan; Heggestad, Eric D.; Myers, Haley; Yap, Tracey L.

    2015-01-01

    An effective workforce performing within the context of a positive cultural environment is central to a healthcare organization’s ability to achieve quality outcomes. The Nursing Culture Assessment Tool (NCAT) provides nurses with a valid and reliable tool that captures the general aspects of nursing culture. This study extends earlier work confirming the tool’s construct validity and dimensionality by standardizing the scoring approach and establishing norm-referenced scoring. Scoring standardization provides a reliable point of comparison for NCAT users. NCAT assessments support nursing’s ability to evaluate nursing culture, use results to shape the culture into one that supports change, and advance nursing’s best practices and care outcomes. Registered nurses, licensed practical nurses, and certified nursing assistants from 54 long-term care facilities in Kentucky, Nevada, North Carolina, and Oregon were surveyed. Confirmatory factor analysis yielded six first order factors forming the NCAT’s subscales (Expectations, Behaviors, Teamwork, Communication, Satisfaction, Commitment) (Comparative Fit Index 0.93) and a second order factor—The Total Culture Score. Aggregated facility level comparisons of observed group variance with expected random variance using rwg(J) statistics is presented. Normative scores and cumulative rank percentages and how the NCAT can be used in implementing planned change are provided.

  12. A meta-analysis of apremilast on psoriatic arthritis long-term assessment of clinical efficacy (PALACE).

    PubMed

    Qu, Xiaoyu; Zhang, Sixi; Tao, Lina; Song, Yanqing

    2016-06-01

    The aim of this article was to assess the efficacy and safety of apremilast in treatment of psoriatic arthritis (PsA) with meta-analysis method. We included four randomized clinical trials identified from MEDLINE, EMBASE, Cochrane Library, "ISRCTN Register" and "ClinicalTrials.gov" which compared apremilast with placebo. The meta-analysis was performed by the software of Review Manager, version 5.2. Apremilast was associated with significantly higher proportion of patients who achieved ACR20 at week 16 (in apremilast 20 mg subgroup, odds ratio [OR]= 2.04, 95% confidence interval [Cl] 1.58-2.63, P<0.00001; in apremilast 30 mg subgroup, OR=2.53, 95%Cl 1.96-3.25, P<0.00001) and significantly higher scores of Health Assessment Questionnaire-Disability Index (in apremilast 20 mg subgroup, WMD=-0.11, 95%Cl -0.16~-0.06, P<0.0001; in apremilast 30 mg subgroup, WMD=-0.16, 95%Cl -0.21~-0.11, P<0.00001). Apremilast was as safe as placebo in terms of serious adverse events (AEs). The AEs occurred in participants with apremilast were mild and well tolerated during treatment. Apremilast can be used in treatment of PsA with lower costs, oral availability and well tolerated. But the long-term benefit and safety of apremilast should be further investigated. PMID:26918950

  13. Bayesian event tree for long-term volcanic hazard assessment: Application to Teide-Pico Viejo stratovolcanoes, Tenerife, Canary Islands

    NASA Astrophysics Data System (ADS)

    Sobradelo, R.; Martí, J.

    2010-05-01

    In modern volcanology one of the most important goals is to perform hazard and risk assessment of volcanoes near urbanized areas. Previous work has been done to assess volcanic hazard in the form of event tree structures containing possible eruptive scenarios. Probability methods have been applied to these structures to estimate the long term probability for each scenario. However, most of these event tree models show restrictions in the eruptive scenarios they consider and/or on the possibility of having volcanic unrest triggered by other forces than magmatic. In this paper, we present a Bayesian event tree structure which accounts for external triggers (geothermal, seismic) as a source of volcanic unrest and looks at the hazard from different types of magma composition and different vent locations (as opposite to a central vent only). We apply the model to the particular case of Teide-Pico Viejo stratovolcanoes, two alkaline composite volcanoes that have erupted 1.8-3 km3 of mafic and felsic magmas from different vent sites during the last 35 ka, situated on a densely populated island, one of the biggest tourist destinations of Europe, and for which limited geological and no historical data exist. Hence, the importance of volcanic hazard assessment for risk-based decision-making in land use planning and emergency management. A previous attempt to estimate the volcanic hazard for Teide-Pico Viejo has been done using an event tree structure based on Elicitation of Expert Judgment. The new method overcomes some limitations of the previous method, including human decision bias, epistemic and aleatoric uncertainties, restrictions on the segmentation complexity of the event tree structure, and automatically updating. The main steps are the following: (1) Design an extensive tree-shaped Bayesian network with possible eruptive scenarios following the case of Teide-Pico Viejo volcanic complex. (2) Build a Bayesian model to estimate the long term volcanic hazard for each

  14. Long-term assessment of insecticides treatments in West Africa: aquatic entomofauna.

    PubMed

    Yaméogo, L; Crosa, G; Samman, J; Nabé, K; Kondé, F; Tholley, D; Calamari, D

    2001-09-01

    For the control of the Onchocerca volvulus vector in West Africa, up to 18,000 km of rivers from 1975 and up to 50,000 km from 1989 had been partly sprayed weekly with insecticides as part of the Onchocerciasis Control Programme (OCP). To evaluate the possible short-term and long-term effects of the application of insecticides on the non-target fauna, an aquatic monitoring programme was set up during the initial phase of the programme. By analysing the invertebrate data, which were collected using various sampling strategies from four different countries between 1977 and 1996, this paper evaluates the long-term changes of the invertebrate populations with respect to their taxonomic composition as well as their trophic structures. The discussed results of the applied numerical analysis strategy suggest that neither the taxonomic nor the trophic structures are greatly altered from the range of biological, flow-related variation that normally occurs in the studied river systems. This allows us to conclude that the biological variation found here is ecologically acceptable. PMID:11534907

  15. Generalized discriminant analysis for congestive heart failure risk assessment based on long-term heart rate variability.

    PubMed

    Shahbazi, Fatemeh; Asl, Babak Mohammadzadeh

    2015-11-01

    The aims of this study are summarized in the following items: first, to investigate the class discrimination power of long-term heart rate variability (HRV) features for risk assessment in patients suffering from congestive heart failure (CHF); second, to introduce the most discriminative features of HRV to discriminate low risk patients (LRPs) and high risk patients (HRPs), and third, to examine the influence of feature dimension reduction in order to achieve desired accuracy of the classification. We analyzed two public Holter databases: 12 data of patients suffering from mild CHF (NYHA class I and II), labeled as LRPs and 32 data of patients suffering from severe CHF (NYHA class III and IV), labeled as HRPs. A K-nearest neighbor classifier was used to evaluate the performance of feature set in the classification. Moreover, to reduce the number of features as well as the overlap of the samples of two classes in feature space, we used generalized discriminant analysis (GDA) as a feature extraction method. By applying GDA to the discriminative nonlinear features, we achieved sensitivity and specificity of 100% having the least number of features. Finally, the results were compared with other similar conducted studies regarding the performance of feature selection procedure and classifier besides the number of features used in training. PMID:26344584

  16. Investigation into the long-term effects of static and PNF stretching exercises on range of motion and jump performance.

    PubMed

    Yuktasir, Bekir; Kaya, Fatih

    2009-01-01

    The purpose of the present study was to investigate the long-term effects of two different stretching techniques on the range of motion (ROM) and on drop jump (DJ). DJ scores were assessed by means of a contact mat connected to a digital timer. ROM was measured by use of a goniometer. The training was carried out four times a week for 6 weeks on 10 subjects as passive static stretching (SS), and on 9 subjects as contract-relax PNF (CRPNF) stretching. The remaining nine subjects did not perform any exercises (control group). One-way Analysis of Variance (ANOVA) results indicated that the differences among groups on DJ were not statistically different (F(2,27)=.41, p>.05). ROM values were significantly higher for both stretching groups, while no change was observed for the control group. In conclusion, static and proprioceptive neuromuscular facilitation (PNF) stretching techniques improved the ROM, but neither of the stretching exercises had any statistically significant effect on the DJ scores. PMID:19118789

  17. Use of a mobile device by nursing home residents for long-term care comprehensive geriatric self-assessment: a feasibility study.

    PubMed

    Huang, Fanpin; Chang, Polun; Hou, I-Ching; Tu, Ming-Hsiang; Lan, Chung-Fu

    2015-01-01

    Long-term-care comprehensive geriatric assessments, such as the Minimum Data Set 3.0, are used to evaluate the clinical, psychological, and personal status of residents in long-term-care nursing facilities. Nursing staff conducts assessment interviews, thereby increasing the workload of nurses and the cost of patient care. This study explored the ability of nursing home residents to use two different mobile devices for a geriatric self-assessment. Study participants were residents of long-term-care nursing homes. A modified Minimum Data Set 3.0 was converted to a format for use with a 6-inch mobile pad and a 3.7-inch mobile smartphone. The survey completion rate and the response time were measured. A Technology Assessment Model questionnaire analyzed the participants' experience. All participants were able to use a 6-inch pad, with an average completion rate of 92.9% and an average time for completion of 21 minutes. Only 20% of the participants could complete the assessment with the 3.7-inch smartphone. The participants found the 6-inch pad easier to use than the 3.7-inch smartphone. This exploratory study suggests that nursing home residents are able to use a mobile device to perform a geriatric self-assessment and delineates the importance of the ergonomics of the device. PMID:25397723

  18. Long-term performance and microbial ecology of a two-stage PN-ANAMMOX process treating mature landfill leachate.

    PubMed

    Li, Huosheng; Zhou, Shaoqi; Ma, Weihao; Huang, Pengfei; Huang, Guotao; Qin, Yujie; Xu, Bin; Ouyang, Hai

    2014-05-01

    Long-term performance of a two-stage partial nitritation (PN)-anaerobic ammonium oxidation (ANAMMOX) process treating mature landfill leachate was investigated. Stable partial nitritation performance was achieved in a sequencing batch reactor (SBR) using endpoint pH control, providing an effluent with a ratio of NO2(-)-N/NH4(+)-N at 1.23 ± 0.23. High rate nitrogen removal over 4 kg N/m(3)/d was observed in the ANAMMOX reactor in the first three months. However, during long-term operation, the ANAMMOX reactor can only stably operate under nitrogen load of 1 kg N/m(3)/d, with 85 ± 1% of nitrogen removal. The ammonium oxidizing bacteria (AOB) in the PN-SBR were mainly affiliated to Nitrosomonas sp. IWT514, Nitrosomonas eutropha and Nitrosomonas eutropha, the anaerobic ammonium oxidizing bacteria (AnAOB) in the ANAMMOX reactor were mainly affiliated to Kuenenia stuttgartiensis. PMID:24681301

  19. Long Term Performance Metrics of the GD SDR on the SCaN Testbed: The First Year on the ISS

    NASA Technical Reports Server (NTRS)

    Nappier, Jennifer; Wilson, Molly C.

    2014-01-01

    The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCaN) Testbed on the International Space Station (ISS) provides experimenters an opportunity to develop and demonstrate experimental waveforms in space. The SCaN Testbed was installed on the ISS in August of 2012. After installation, the initial checkout and commissioning phases were completed and experimental operations commenced. One goal of the SCaN Testbed is to collect long term performance metrics for SDRs operating in space in order to demonstrate long term reliability. These metrics include the time the SDR powered on, the time the power amplifier (PA) is powered on, temperature trends, error detection and correction (EDAC) behavior, and waveform operational usage time. This paper describes the performance of the GD SDR over the first year of operations on the ISS.

  20. Aligned Single-Crystalline Perovskite Microwire Arrays for High-Performance Flexible Image Sensors with Long-Term Stability.

    PubMed

    Deng, Wei; Zhang, Xiujuan; Huang, Liming; Xu, Xiuzhen; Wang, Liang; Wang, Jincheng; Shang, Qixun; Lee, Shuit-Tong; Jie, Jiansheng

    2016-03-16

    A simple, low-cost blade-coating method is developed for the large-area fabrication of single-crystalline aligned CH3NH3PbI3 microwire (MW) arrays. The solution-coating method is applicable to flexible substrates, enabling the fabrication of MW-array-based photodetectors with excellent long-term stability, flexibility, and bending durability. Integrated devices from such photodetectors demonstrate high performance for high-resolution, flexible image sensors. PMID:26780594

  1. Death in Long-term Care: A Brief Report Examining Factors Associated with Death within 31 Days of Assessment

    PubMed Central

    Brink, Peter; Kelley, Mary Lou

    2015-01-01

    INTRODUCTION The ability to estimate prognosis using administrative data has already been established. Research indicates that residents newly admitted to long-term care are at a higher risk of mortality. Studies have also examined mortality within 90 days or a year. Focusing on 31 days from assessment was important because it appears to be clinically useful for care planning in end-of-life; whereby, greater utility may come from identifying residents who are at risk of death within a shorter time frame so that advance care planning can occur. PURPOSE To examine risk of mortality within 31 days of assessment among long-term care residents using administrative health data. METHODS Administrative data were used to examine risk of mortality within 31 days of assessment among all long-term care residents in Ontario over a 12-month period. Data were provided by the Canadian Institute for Health Information using the Continuing Care Reporting System (CCRS), Discharge Abstract Database (DAD), and the National Ambulatory Care Reporting System (NACRS). RESULTS A number of diagnoses and health conditions predict death within 31 days. Diagnoses that hold an increased risk of mortality include pulmonary disease, diagnosis of cancer, and heart disease. Health conditions that lead to an increased likelihood of death include weight loss, dehydration, and shortness of breath. The presence of a fall within the last 30 days was also related to a higher risk of mortality. DISCUSSION Long-term care residents who lose weight, have persistent problems with hydration, and suffer from shortness of breath are at particular risk of death. The presence of advanced directives also predicts death within 31 days of assessment. PMID:25674000

  2. Assessment of inceptisols soil quality following long-term cropping in a calcareous environment.

    PubMed

    Rezapour, Salar; Samadi, A

    2012-03-01

    The combination of morphological, clay mineralogy, physicochemical, and fertilitical properties of inceptisols were compared for monitoring soil quality response following long-term agricultural activities. For this target, fifty-nine paired surface soils belonging to five subgroups of inceptisols from the major sugar beet growing area and the adjoining virgin lands were described, sampled, and analyzed. The soils were alkaline and calcareous as characterized by high pH, ranging from 7.2 to 8, and calcium carbonate equivalent, ranging from 60 to 300 g kg(-1). Following long-term sugar beet cultivation, morphological properties modifications were reflected as weakening of structure, hardening of consistency, and brightening of soil color. Although, the quantity of clay minerals did not significantly change through long-term cropping, some modifications in the XRD pattern of illite and smectite were observed in the cultivated soils compared to the adjoining virgin lands mainly as a result of potassium depletion. Without significant variation, sand content decreased by 4-55% and silt and clay increased by 3-22% and 2-15%, respectively, in the cultivated soils than to that of the virgin lands. Both negative and positive aspects of soil quality were reflected regarding soil chemical and fertilitical properties and the role of negative effects far exceeded the role of positive effects. Typic calcixerepts was known to be more degraded through a significant decrease (P ≤ 0.001) in mean value of soil organic carbon (a drop of 24%), total N (a drop of 23%), available K (a drop of 42%), exchangeable K (a drop of 45%), potassium adsorption ratio and potassium saturation ratio (a drop of 44% and 42%, respectively) and a significant increase (P ≤ 0.001) in EC (a rise of 53%). Soil quality index, calculated based on nine soil properties [coarse fragments, pH, SOC, total N, ESP, exchangeable cations (Ca, Mg, and K), and available phosphorus], indicated that 60% of the all soil

  3. Assessing climate change and socio-economic uncertainties in long term management of water resources

    NASA Astrophysics Data System (ADS)

    Jahanshahi, Golnaz; Dawson, Richard; Walsh, Claire; Birkinshaw, Stephen; Glenis, Vassilis

    2015-04-01

    Long term management of water resources is challenging for decision makers given the range of uncertainties that exist. Such uncertainties are a function of long term drivers of change, such as climate, environmental loadings, demography, land use and other socio economic drivers. Impacts of climate change on frequency of extreme events such as drought make it a serious threat to water resources and water security. The release of probabilistic climate information, such as the UKCP09 scenarios, provides improved understanding of some uncertainties in climate models. This has motivated a more rigorous approach to dealing with other uncertainties in order to understand the sensitivity of investment decisions to future uncertainty and identify adaptation options that are as far as possible robust. We have developed and coupled a system of models that includes a weather generator, simulations of catchment hydrology, demand for water and the water resource system. This integrated model has been applied in the Thames catchment which supplies the city of London, UK. This region is one of the driest in the UK and hence sensitive to water availability. In addition, it is one of the fastest growing parts of the UK and plays an important economic role. Key uncertainties in long term water resources in the Thames catchment, many of which result from earth system processes, are identified and quantified. The implications of these uncertainties are explored using a combination of uncertainty analysis and sensitivity testing. The analysis shows considerable uncertainty in future rainfall, river flow and consequently water resource. For example, results indicate that by the 2050s, low flow (Q95) in the Thames catchment will range from -44 to +9% compared with the control scenario (1970s). Consequently, by the 2050s the average number of drought days are expected to increase 4-6 times relative to the 1970s. Uncertainties associated with urban growth increase these risks further

  4. Long-term persistence of throughfall yield assessed by small footprint LiDAR data

    NASA Astrophysics Data System (ADS)

    Bischoff, Sebastian; Levia, Delphis F.; Nieschulze, Jens; Schulz, Florian; Michalzik, Beate

    2016-04-01

    Throughfall (TF) represents an important relocation mechanism for the spatial distribution of intercepted precipitation and hence associated nutrients in wooded ecosystems. To date, a broad range of studies showed that the spatial patterns of TF distribution exhibit a pronounced temporal stability. These studies, however, have examined TF temporal stability at the tree scale or they were computed from event-based data. Here, we seek to evaluate the utility of temporally aggregated TF data at one, three, and six year intervals to determine whether such long-term TF monitoring data could serve as the basis for TF temporal persistence measurements for both beech and spruce forests. In addition, we examine the temporal persistence of TF in relation to small footprint LiDAR data. In context of the German Science Foundation (DFG) founded "Biodiversity Exploratories" (www.biodiversity-exploratories.de) we studied water-bound nutrient fluxes on a set of three differently managed forest plots (spruce plantation, age class forest beech, unmanaged beech) in central Germany throughout the vegetation periods of 2010 - 2015. For long-term monitoring purposes, TF samples were collected in biweekly routine sampling intervals using X-shaped transects of 20 bulk samplers (axis length 32 m) per experimental plot. In this study, we aim to identify canopy structural parameters explaining the temporal patterns observed. We therefore used small footprint LiDAR (Light Detection And Ranging) data to calculate several canopy structural parameters on base of a gridded canopy model (grid cell resolution = 0.75 m). As LiDAR allows a three-dimensional description of the complex forest canopy structure it might help to extend our understanding of complex canopy processes influencing the spatial dispersal of precipitation water, and hence associated nutrient fluxes, in wooded ecosystems. Preliminary data analysis reveals that normalized TF values identify a number of TF collectors on each of the

  5. Protective Effect of Long-Term CPAP Therapy on Cognitive Performance in Elderly Patients with Severe OSA: The PROOF Study

    PubMed Central

    Crawford-Achour, Emilie; Dauphinot, Virginie; Saint Martin, Magali; Tardy, Magali; Gonthier, Régis; Barthelemy, Jean Claude; Roche, Frédéric

    2015-01-01

    Objective: Obstructive sleep apnea syndrome (OSA) leads to a deterioration in cognitive functions, with regard to memory and executive functions. However, few studies have investigated the impact of treatment on these cognitive functions in elderly subjects. Methods: The study was conducted in a large cohort of subjects aged 65 years or older (the PROOF cohort). Subjects were not diagnosed or treated for OSA. Subjects underwent a polygraphic recording. Cognitive performance was assessed in all OSA subjects at baseline and 10 years later, whether or not they were receiving continuous positive airway pressure (CPAP) therapy. Results: A group of 126 patients were analyzed. Only 26% of them were treated, with therapy initiated at the discretion of the primary care physician. Among treated subjects, self-reported compliance with therapy was good (> 6 h/night on average), and 66% of them reported an improvement in their quality of life. Patients receiving CPAP treatment had a higher apneahypopnea index (p = 0.006), a higher oxygen desaturation index (p < 0.001), and experienced more pronounced daytime repercussions (p = 0.004). These patients showed a statistically significant improvement in mental agility (similarities test; p < 0.0001) and memory performance (Grober and Buschke delayed free recall; p = 0.02). Conclusion: CPAP treatment is associated with the maintenance of memory performance over time. Citation: Crawford-Achour E, Dauphinot V, Saint Martin M, Tardy M, Gonthier R, Barthelemy JC, Roche F. Protective effect of long-term CPAP therapy on cognitive performance in elderly patients with severe OSA: the PROOF study. J Clin Sleep Med 2015;11(5):519–524. PMID:25700873

  6. Magnetic resonance imaging: opportunities for rheumatoid arthritis disease assessment and monitoring long-term treatment outcomes

    PubMed Central

    2002-01-01

    Early diagnosis of rheumatoid arthritis (RA) combined with early initiation of an appropriate treatment regimen is acknowledged as an important factor in improving clinical outcomes in patients with RA. Early diagnosis allows treatment intervention to occur sooner in order to inhibit the progression of structural joint damage as well as providing improved patient quality of life. Unfortunately, early diagnosis has been challenging due to the non-specific signs and symptoms associated with many polyarthropathies and the lack of accurate definitive diagnostic tests that can accurately classify RA at presentation. The emphasis on early diagnosis has fueled the need for powerful, sensitive, non-invasive imaging techniques that not only accurately define RA and give an indication of prognosis, but can also serve as a tool to monitor long-term treatment outcomes. This article reviews the potential uses of magnetic resonance imaging as a tool for the classification, documentation, and clinical monitoring of RA. PMID:12110151

  7. Indications and long-term assessment of 10 cases of cross-leg free DCIA flaps.

    PubMed

    Townsend, P L

    1987-09-01

    Compound fractures of the lower limb with skin and bone loss are difficult repair problems, especially in multiple level injuries. With bone loss between 6 and 12 cms, the deep circumflex iliac artery (DCIA) flap is usually the flap of choice in reconstruction; the aim is to carry out microvascular anastomosis of the flap vessels to vessels on the damaged leg. However, this may be difficult or even impossible. Experience of 10 cross-leg DCIA flaps is outlined, with indications and surgical technique. The long-term bone healing is compared with 13 cases with anastomosis based on the same leg. There appears to be no difference in callus formation and remodelling of bone, indicating that despite subsequently dividing the original main vascular supply the bone in the DCIA flap remains vascularized and behaves as such. PMID:3310809

  8. Assessment of Myocardial Infarction by Cardiac Magnetic Resonance Imaging and Long-Term Mortality

    PubMed Central

    Petriz, João Luiz Fernandes; Gomes, Bruno Ferraz de Oliveira; Rua, Braulio Santos; Azevedo, Clério Francisco; Hadlich, Marcelo Souza; Mussi, Henrique Thadeu Periard; Taets, Gunnar de Cunto; do Nascimento, Emília Matos; Pereira, Basílio de Bragança; e Silva, Nelson Albuquerque de Souza

    2015-01-01

    Background Cardiac magnetic resonance imaging provides detailed anatomical information on infarction. However, few studies have investigated the association of these data with mortality after acute myocardial infarction. Objective To study the association between data regarding infarct size and anatomy, as obtained from cardiac magnetic resonance imaging after acute myocardial infarction, and long-term mortality. Methods A total of 1959 reports of “infarct size” were identified in 7119 cardiac magnetic resonance imaging studies, of which 420 had clinical and laboratory confirmation of previous myocardial infarction. The variables studied were the classic risk factors – left ventricular ejection fraction, categorized ventricular function, and location of acute myocardial infarction. Infarct size and acute myocardial infarction extent and transmurality were analyzed alone and together, using the variable named “MET-AMI”. The statistical analysis was carried out using the elastic net regularization, with the Cox model and survival trees. Results The mean age was 62.3 ± 12 years, and 77.3% were males. During the mean follow-up of 6.4 ± 2.9 years, there were 76 deaths (18.1%). Serum creatinine, diabetes mellitus and previous myocardial infarction were independently associated with mortality. Age was the main explanatory factor. The cardiac magnetic resonance imaging variables independently associated with mortality were transmurality of acute myocardial infarction (p = 0.047), ventricular dysfunction (p = 0.0005) and infarcted size (p = 0.0005); the latter was the main explanatory variable for ischemic heart disease death. The MET-AMI variable was the most strongly associated with risk of ischemic heart disease death (HR: 16.04; 95%CI: 2.64-97.5; p = 0.003). Conclusion The anatomical data of infarction, obtained from cardiac magnetic resonance imaging after acute myocardial infarction, were independently associated with long-term mortality, especially for

  9. Perceived Barriers to Effective Job Performance Among Nursing Assistants in Long-Term Care

    PubMed Central

    Parmelee, Patricia A.; Laszlo, Mary C.; Taylor, Jo A.

    2009-01-01

    Objectives: This research explored perceived barriers to job performance among a national sample of nursing assistants (NAs). Specific objectives were (a) to clarify which of the problems identified by previous research are most troublesome for NAs, (b) to develop a reliable quantitative measure of perceived barriers to job performance, and (c) to test construct validity of the measure vis-à-vis work-related psychological empowerment and job satisfaction. Methods: Nursing assistants attending the 2006 national conference of the National Association of Health Care Assistants completed a paper-and-pencil survey including 33 barriers to job performance and standardized measures of empowerment and job satisfaction. The barries were also rated by a small sample of NAs at a single Georgia nursing home. Results: Factor analysis of barriers items yielded a 30-item Nursing Assistants Barriers Scale (NABS) comprising 6 subscales: Teamwork, Exclusion, Respect, Workload, Work Stress, and New NAs. Lack of teamwork and exclusion from communication processes were rated as most problematic by both samples. The 6 NABS subscales were significantly and independently associated with empowerment and satisfaction; different barriers predicted the two constructs. Discussion: This study is a first step toward quantitative assessment of NAs' perceptions of barriers to doing their jobs. Primary limitations are the select sample and use of a job satisfaction measure that may have artificially inflated correlations with the NABS. Nonetheless, results confirm the validity of the new scale as an operationalization of the barriers construct. Conclusion: The concept of barriers to job performance is a unique construct from work empowerment and satisfaction with one's job. Nursing assistants clearly differentiate various barriers, converging on workload and lack of teamwork as most problematic. Further work is needed to substantiate validity and reliability of the NABS, particularly with respect

  10. Technical description of the NRC long-term whole-rod and crud performance test

    SciTech Connect

    Einziger, R.E.; Fish, R.L.; Knecht, R.L.

    1982-09-01

    Westinghouse Hanford Company (WHC) and EG and G-Idaho are jointly conducting a long-term, low-temperature, spent-fuel, whole rod and crud behavior test to provide the Nuclear Regulatory Commission (NRC) with information to assist in the licensing of light water reactor (LWR) spent-fuel, dry storage facilities. Readily available fuel rods from an H.B. Robinson Unit 2 (PWR) fuel assembly and a Peach Bottom-II (BWR) fuel assembly were selected for use in the 50-month test. Both intact and defected rods will be tested in inert and oxidizing atmospheres. A 230/sup 0/C test temperature was selected for the first 10-month run. Both nondestructive and destructive examinations are planned to characterize the fuel rod behavior during the 5-y test. Four interim examinations and a final examination will be conducted. Crud spallation behavior will be investigated by sampling the crud particulate from the test capsules at each of the four interim examinations and at the end of the test. The background to whole rod testing, description of rod breach mechanisms, and a detailed description of the test are presented in this document.

  11. Use of non evaporable getter pumps to ensure long term performances of high quantum efficiency photocathodes

    SciTech Connect

    Sertore, Daniele Michelato, Paolo; Monaco, Laura; Manini, Paolo; Siviero, Fabrizio

    2014-05-15

    High quantum efficiency photocathodes are routinely used as laser triggered emitters in the advanced high brightness electron sources based on radio frequency guns. The sensitivity of “semiconductor” type photocathodes to vacuum levels and gas composition requires special care during preparation and handling. This paper will discuss the results obtained using a novel pumping approach based on coupling a 20 l s{sup −1} sputter ion getter pump with a CapaciTorr® D100 non evaporable getter (NEG) pump. A pressure of 8⋅10{sup −8} Pa was achieved using only a sputter ion pump after a 6 day bake-out. With the addition of a NEG pump, a pressure of 2⋅10{sup −9} Pa was achieved after a 2 day bake-out. These pressure values were maintained without power due to the ability of the NEG to pump gases by chemical reaction. Long term monitoring of cathodes quantum efficiencies was also carried out at different photon wavelengths for more than two years, showing no degradation of the photoemissive film properties.

  12. Long term magnetic performance of the steel concrete dipoles in LEP

    SciTech Connect

    Billan, J.; Gourber, J.P.; Henrichsen, K.N.

    1994-07-01

    The steel-concrete cores of the LEP bending magnets were built of regularly spaced steel laminations, the spaces being filled with cement mortar. The effects of compressive stresses were studied on models and the long term behavior has been monitored during operation of the LEP machine over a period of four years. The requirements for stability and reproducibility of the magnetic field have increased in step with the development of the accelerator and its particle detectors. After the initial aging in the LEP tunnel, the most important parameter was the temperature coefficient. The temperatures of a number of magnet cores are therefore continuously monitored and corrections are applied to the indicated value of particle momentum as measured by NMR and a flip coil in a reference dipole connected in series with the bending magnets. This reference magnet is in turn calibrated periodically by a direct measurement of flux variations in a loop mounted in the lower poles of all bending magnets installed in the tunnel

  13. Long-term performance analysis of copper indium gallium selenide thin-film photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Kaul, Ashwani; Pethe, Shirish A.; Dhere, Neelkanth G.

    2012-01-01

    Current accelerated qualification tests of photovoltaic (PV) modules mostly assist in avoiding premature failures but can neither duplicate changes occurring in the field nor predict useful product lifetime. Therefore, outdoor monitoring of field-deployed thin-film PV modules was undertaken at FSEC with the goal of assessing their performance in hot and humid climate under high system-voltage operation. Significant and comparable degradation rate of -5.13±1.53% and -4.5±1.46% per year was found using PVUSA type regression analysis for the positive and negative strings, respectively of 40W glass-to-glass Cu-In-Ga-Se (CIGS) thin-film PV modules in the hot and humid climate of Florida. Using the current-voltage measurements, it was found that the performance degradation within the PV array was mainly due to a few (8% to 12%) modules that had substantially higher degradation. The remaining modules within the array continued to show reasonable performance (>96% of the rated power after ˜ four years).

  14. Assessing Forest Carbon Response to Climate Change and Disturbances Using Long-term Hydro-climatic Observations and Simulations

    NASA Astrophysics Data System (ADS)

    Trettin, C.; Dai, Z.; Amatya, D. M.

    2014-12-01

    Long-term climatic and hydrologic observations on the Santee Experimental Forest in the lower coastal plain of South Carolina were used to estimate long-term changes in hydrology and forest carbon dynamics for a pair of first-order watersheds. Over 70 years of climate data indicated that warming in this forest area in the last decades was faster than the global mean; 35+ years of hydrologic records showed that forest ecosystem succession three years following Hurricane Hugo caused a substantial change in the ratio of runoff to precipitation. The change in this relationship between the paired watersheds was attributed to altered evapotranspiration processes caused by greater abundance of pine in the treatment watershed and regeneration of the mixed hardwood-pine forest on the reference watershed. The long-term records and anomalous observations are highly valuable for reliable calibration and validation of hydrological and biogeochemical models capturing the effects of climate variability. We applied the hydrological model MIKESHE that showed that runoff and water table level are sensitive to global warming, and that the sustained warming trends can be expected to decrease stream discharge and lower the mean water table depth. The spatially-explicit biogeochemical model Forest-DNDC, validated using biomass measurements from the watersheds, was used to assess carbon dynamics in response to high resolution hydrologic observation data and simulation results. The simulations showed that the long-term spatiotemporal carbon dynamics, including biomass and fluxes of soil carbon dioxide and methane were highly regulated by disturbance regimes, climatic conditions and water table depth. The utility of linked-modeling framework demonstrated here to assess biogeochemical responses at the watershed scale suggests applications for assessing the consequences of climate change within an urbanizing forested landscape. The approach may also be applicable for validating large

  15. Assessing Watershed-Scale, Long-Term Hydrologic Impacts of Land-Use Change Using a GIS-NPS Model

    NASA Astrophysics Data System (ADS)

    Bhaduri, Budhendra; Harbor, Jon; Engel, Bernie; Grove, Matt

    2000-12-01

    Land-use change, dominated by an increase in urban/impervious areas, has a significant impact on water resources. This includes impacts on nonpoint source (NPS) pollution, which is the leading cause of degraded water quality in the United States. Traditional hydrologic models focus on estimating peak discharges and NPS pollution from high-magnitude, episodic storms and successfully address short-term, local-scale surface water management issues. However, runoff from small, low-frequency storms dominates long-term hydrologic impacts, and existing hydrologic models are usually of limited use in assessing the long-term impacts of land-use change. A long-term hydrologic impact assessment (L-THIA) model has been developed using the curve number (CN) method. Long-term climatic records are used in combination with soils and land-use information to calculate average annual runoff and NPS pollution at a watershed scale. The model is linked to a geographic information system (GIS) for convenient generation and management of model input and output data, and advanced visualization of model results. The L-THIA/NPS GIS model was applied to the Little Eagle Creek (LEC) watershed near Indianapolis, Indiana, USA. Historical land-use scenarios for 1973, 1984, and 1991 were analyzed to track land-use change in the watershed and to assess impacts on annual average runoff and NPS pollution from the watershed and its five subbasins. For the entire watershed between 1973 and 1991, an 18% increase in urban or impervious areas resulted in an estimated 80% increase in annual average runoff volume and estimated increases of more than 50% in annual average loads for lead, copper, and zinc. Estimated nutrient (nitrogen and phosphorus) loads decreased by 15% mainly because of loss of agricultural areas. The L-THIA/NPS GIS model is a powerful tool for identifying environmentally sensitive areas in terms of NPS pollution potential and for evaluating alternative land use scenarios for NPS

  16. Assessing Transformations of Algal Organic Matter in the Long-Term: Impacts of Humification-Like Processes

    PubMed Central

    Leloup, Maud; Pallier, Virginie; Nicolau, Rudy; Feuillade-Cathalifaud, Geneviève

    2015-01-01

    Algae and cyanobacteria are important contributors to the natural organic matter (NOM) of eutrophic water resources. The objective of this work is to increase knowledge on the modifications of algal organic matter (AOM) properties in the long term to anticipate blooms footprint in such aquatic environments. The production of AOM from an alga (Euglena gracilis) and a cyanobacteria (Microcystis aeruginosa) was followed up and characterized during the stationary phase and after one year and four months of cultivation, in batch experiments. Specific UV absorbance (SUVA) index, organic matter fractionation according to hydrophobicity and apparent molecular weight were combined to assess the evolution of AOM. A comparison between humic substances (HS) mainly derived from allochthonous origins and AOM characteristics was performed to hypothesize impacts of AOM transformation processes on the water quality of eutrophic water resources. Each AOM fraction underwent a specific evolution pattern, depending on its composition. Impacts of humification-like processes were predominant over release of biopolymers due to cells decay and led to an increase in the hydrophobic compounds part and molecular weights over time. However, the hydrophilic fraction remained the major fraction whatever the growth stage. Organic compounds generated by maturation of these precursors corresponded to large and aliphatic structures. PMID:26251898

  17. Assessing Transformations of Algal Organic Matter in the Long-Term: Impacts of Humification-Like Processes.

    PubMed

    Leloup, Maud; Pallier, Virginie; Nicolau, Rudy; Feuillade-Cathalifaud, Geneviève

    2015-01-01

    Algae and cyanobacteria are important contributors to the natural organic matter (NOM) of eutrophic water resources. The objective of this work is to increase knowledge on the modifications of algal organic matter (AOM) properties in the long term to anticipate blooms footprint in such aquatic environments. The production of AOM from an alga (Euglena gracilis) and a cyanobacteria (Microcystis aeruginosa) was followed up and characterized during the stationary phase and after one year and four months of cultivation, in batch experiments. Specific UV absorbance (SUVA) index, organic matter fractionation according to hydrophobicity and apparent molecular weight were combined to assess the evolution of AOM. A comparison between humic substances (HS) mainly derived from allochthonous origins and AOM characteristics was performed to hypothesize impacts of AOM transformation processes on the water quality of eutrophic water resources. Each AOM fraction underwent a specific evolution pattern, depending on its composition. Impacts of humification-like processes were predominant over release of biopolymers due to cells decay and led to an increase in the hydrophobic compounds part and molecular weights over time. However, the hydrophilic fraction remained the major fraction whatever the growth stage. Organic compounds generated by maturation of these precursors corresponded to large and aliphatic structures. PMID:26251898

  18. Short-Duration and Intensive Training Improves Long-Term Reaching Performance in Individuals With Chronic Stroke.

    PubMed

    Park, Hyeshin; Kim, Sujin; Winstein, Carolee J; Gordon, James; Schweighofer, Nicolas

    2016-07-01

    Previous studies have shown that multiple sessions of reach training lead to long-term improvements in movement time and smoothness in individuals post-stroke. Yet such long-term training regimens are often difficult to implement in actual clinical settings. In this study, we evaluated the long-term and generalization effects of short-duration and intensive reach training in 16 individuals with chronic stroke and mild to moderate impairments. Participants performed 2 sessions of unassisted intensive reach training, with 600 movements per session, and with display of performance-based feedback after each movement. The participants' trunks were restrained with a belt to avoid compensatory movements. Training resulted in significant and durable (1 month) improvements in movement time (20.4% on average) and movement smoothness (22.7% on average). The largest improvements occurred in individuals with the largest initial motor impairments. In addition, training induced generalization to nontrained targets, which persisted in 1-day and in 1-month retention tests. Finally, there was a significant improvement in the Box and Block test from baseline to 1-month retention test (23% on average). Thus, short-duration and intensive reach training can lead to generalized and durable benefits in individuals with chronic stroke and mild to moderate impairments. PMID:26405046

  19. Iliac Crest Donor Site for Children With Cleft Lip and Palate Undergoing Alveolar Bone Grafting: A Long-term Assessment.

    PubMed

    Wheeler, Jonathan; Sanders, Megan; Loo, Stanley; Moaveni, Zac; Bartlett, Glenn; Keall, Heather; Pinkerton, Mark

    2016-05-01

    The authors aimed to accurately assess the donor site morbidity from iliac crest bone grafts for secondary bone grafting in patients with cleft lip and palate alveolar defects. Fifty patients between 3 months and 10 years following alveolar bone grafting for cleft lip and palate were entered into the study. Two-thirds of patients had no significant concerns about the donor site. The remaining third had some concerns about the appearance of their hips and less than 10% of patients expressing strong agreement with statements about concerns with shape, appearance, and self-consciousness about the iliac crest donor site. Examination findings showed the average length of scar being 5.4 cm and a third of patients having some minor palpable boney irregularities of the iliac crest. The authors found that the alveolar crest donor site is well tolerated by patients long term but has a measurable morbidity long term. PMID:27035602

  20. Accelerated ageing of an EAF black slag by carbonation and percolation for long-term behaviour assessment.

    PubMed

    Gurtubay, L; Gallastegui, G; Elias, A; Rojo, N; Barona, A

    2014-07-01

    The efficient reuse of industrial by-products, such as the electric arc furnace (EAF) black slag, is still hindered by concern over their long-term behaviour in outdoor environments. The aim of this study was to develop an accelerated ageing method to simulate the long-term natural carbonation of EAF slag exposed to the elements. The degree of carbonation achieved in a freshly produced slag after accelerated ageing and in a slag used on a fifteen-year-old unpaved road was very similar. The influence of particle size on accelerated carbonation was assessed, with it being concluded that the slag sample with a particle size bigger than 5-6 mm underwent slight carbonation over time when it was exposed to CO2. The accelerated ageing procedure based on percolating a previously carbonated water solution through the slag column allowed gradual leaching with simulated acid rain, as well as providing information about the gradual and total chemical release from the slag. Three classification groups were established according to the release rate of the determined elements. The joint use of the accelerated carbonation method and the percolation test is proposed as a useful tool for environmental risk assessment concerning the long-term air exposure of EAF black slag. PMID:24726964

  1. Long-Term Performance of Transuranic Waste Inadvertently Disposed in a Shallow Land Burial Trench at the Nevada Test Site

    SciTech Connect

    Gregory J. Shott; Vefa Yucel

    2009-07-16

    In 1986, 21 m3 of transuranic (TRU) waste was inadvertently disposed in a shallow land burial trench at the Area 5 Radioactive Waste Management Site on the Nevada Test Site. U.S. Department of Energy (DOE) TRU waste must be disposed in accordance with Title 40, Code of Federal Regulations (CFR), Part 191, Environmental Radiation Protection Standard for Management and Disposal of Spent Nuclear Fuel, High-Level, and Transuranic Radioactive Wastes. The Waste Isolation Pilot Plant is the only facility meeting these requirements. The National Research Council, however, has found that exhumation of buried TRU waste for disposal in a deep geologic repository may not be warranted when the effort, exposures, and expense of retrieval are not commensurate with the risk reduction achieved. The long-term risks of leaving the TRU waste in-place are evaluated in two probabilistic performance assessments. A composite analysis, assessing the dose from all disposed waste and interacting sources of residual contamination, estimates an annual total effective dose equivalent (TEDE) of 0.01 mSv, or 3 percent of the dose constraint. A 40 CFR 191 performance assessment also indicates there is reasonable assurance of meeting all requirements. The 40 CFR 191.15 annual mean TEDE for a member of the public is estimated to reach a maximum of 0.055 mSv at 10,000 years, or approximately 37 percent of the 0.15 mSv individual protection requirement. In both assessments greater than 99 percent of the dose is from co-disposed low-level waste. The simulated probability of the 40 CFR 191.13 cumulative release exceeding 1 and 10 times the release limit is estimated to be 0.0093 and less than 0.0001, respectively. Site characterization data and hydrologic process modeling support a conclusion of no groundwater pathway within 10,000 years. Monte Carlo uncertainty analysis indicates that there is reasonable assurance of meeting all regulatory requirements. Sensitivity analysis indicates that the results

  2. Long-term performance of passive materials for removal of ozone from indoor air.

    PubMed

    Cros, C J; Morrison, G C; Siegel, J A; Corsi, R L

    2012-02-01

    The health effects associated with exposure to ozone range from respiratory irritation to increased mortality. In this paper, we explore the use of three green building materials and an activated carbon (AC) mat that remove ozone from indoor air. We studied the effects of long-term exposure of these materials to real environments on ozone removal capability and pre- and post-ozonation emissions. A field study was completed over a 6-month period, and laboratory testing was intermittently conducted on material samples retrieved from the field. The results show sustained ozone removal for all materials except recycled carpet, with greatest ozone deposition velocity for AC mat (2.5-3.8 m/h) and perlite-based ceiling tile (2.2-3.2 m/h). Carbonyl emission rates were low for AC across all field sites. Painted gypsum wallboard and perlite-based ceiling tile had similar overall emission rates over the 6-month period, while carpet had large initial emission rates of undesirable by-products that decayed rapidly but remained high compared with other materials. This study confirms that AC mats and perlite-based ceiling tile are viable surfaces for inclusion in buildings to remove ozone without generating undesirable by-products. PRACTICAL IMPLICATIONS The use of passive removal materials for ozone control could decrease the need for, or even render unnecessary, active but energy consuming control solutions. In buildings where ozone should be controlled (high outdoor ozone concentrations, sensitive populations), materials specifically designed or selected for removing ozone could be implemented, as long as ozone removal is not associated with large emissions of harmful by-products. We find that activated carbon mats and perlite-based ceiling tiles can provide substantial, long-lasting, ozone control. PMID:21777291

  3. Performance of multilayer optical coatings under long-term 532nm laser exposure

    NASA Astrophysics Data System (ADS)

    Poulios, D.; Konoplev, O.; Chiragh, F.; Vasilyev, A.; Stephen, M.; Strickler, K.

    2013-11-01

    The effects of long-term exposure to high intensity 532 nm radiation on various dielectric-coated optics are studied. To investigate potential photodarkening effects on optical surfaces, an accelerated life test platform was constructed where optics were exposed to 532 nm radiation from a short-pulse, high repetition rate fiber amplifier at total doses up to 1 trillion shots. The first run of trillion-shot tests were conducted on e-beam deposited and ion beam sputtering (IBS) coated high reflecting mirrors with onsurface intensities ranging from 1.0-1.4 GW/cm2. It was found that the e-beam coated mirrors failed catastrophically at less than 150 billion shots, while the IBS coated mirror was able to complete the trillionshot test with no measurable loss of reflectivity. Profiling the IBS mirror surface with a high-resolution white light interferometer post-irradiation revealed a ~10 nm high photocontamination deposit at the irradiation site that closely matched the intensity profile of the laser spot. Trillion-shot surface exposure tests were also conducted at multiple surface sites of an LBO frequency doubling crystal at ~1.5 GW/cm2 at multiple surface sites. The transmitted power and on-surface beam size were monitored throughout the tests, and periodic measurements of the beam quality and waist location of the transmitted light were also made using an M2 meter. No changes in transmitted power or M2 were observed in any of the tests, but 3D surface profiling revealed laser-induced contamination deposits at each site tested.

  4. Assessment of long-term erosion in a mountain vineyard, Aosta Valley (NW Italy)

    NASA Astrophysics Data System (ADS)

    Biddoccu, Marcella; Zecca, Odoardo; Barmaz, Andrea; Godone, Franco; Cavallo, Eugenio

    2015-04-01

    Tillage and chemical weeding are common soil management techniques adopted in mountain vineyards, with high slope gradient, to maintain bare soil. Both techniques exposes the soil to degradation, favoring runoff and soil losses, that may cause relevant on-site and off-site damage. Steep mountain slopes makes optimum conditions for grape-growing. In the mountain region of Aosta Valley, NW Italy, the vineyards were, in the past, traditionally grown on terraces supported by dry stone walls. Since the 1960s the plantation of vines in the direction of the slope became more and more widespread, also on very steep slopes. Generally, no particular measure to channel and control surface water is adopted in this area due to the low rainfall (560 mm/year). Nevertheless in steep mountain slope rainfall events can cause important runoff erosion. In order to evaluate the long-term effect of vineyard management techniques on soil erosion, a study was carried out on a mountain slope vineyard located near Aosta, at about 900 m above the sea level. The vineyard was planted at the end of 1960s and is managed by the Institut Agricole Régional. The rows are accommodated oriented along the slope, which is about 45%. The inter-rows' soil management of the vineyard included chemical weeding and, in first year after plantation, the adoption of irrigation (by fixed overhead sprinklers) and hilling-up/taking-out the soil around the vine plants, to protect them from cold weather. The long-term soil erosion rate was determined adopting the technique of botanical benchmark (Casalí et al.,2009). The grafting callus was used as a marker to identify the paleo-surface at the time of planting. A detailed topographic survey was carried out to determine the present surface of the vineyard while the current position of the grafting callus was recorded for a number of plants. The original position of the callus was estimated by data obtained by farmers and by a survey on reference vineyards. Two

  5. Long-Term Stability Assessment of Sonoran Desert for Vicarious Calibration of GOES-R

    NASA Astrophysics Data System (ADS)

    Kim, W.; Liang, S.; Cao, C.

    2012-12-01

    Vicarious calibration refers to calibration techniques that do not depend on onboard calibration devices. Although sensors and onboard calibration devices undergo rigorous validation processes before launch, performance of sensors often degrades after the launch due to exposure to the harsh space environment and the aging of devices. Such in-flight changes of devices can be identified and adjusted through vicarious calibration activities where the sensor degradation is measured in reference to exterior calibration sources such as the Sun, the Moon, and the Earth surface. Sonoran desert is one of the best calibration sites located in the North America that are available for vicarious calibration of GOES-R satellite. To accurately calibrate sensors onboard GOES-R satellite (e.g. advanced baseline imager (ABI)), the temporal stability of Sonoran desert needs to be assessed precisely. However, short-/mid-term variations in top-of-atmosphere (TOA) reflectance caused by meteorological variables such as water vapor amount and aerosol loading are often difficult to retrieve, making the use of TOA reflectance time series for the stability assessment of the site. In this paper, we address this issue of normalization of TOA reflectance time series using a time series analysis algorithm - seasonal trend decomposition procedure based on LOESS (STL) (Cleveland et al, 1990). The algorithm is basically a collection of smoothing filters which leads to decomposition of a time series into three additive components; seasonal, trend, and remainder. Since this non-linear technique is capable of extracting seasonal patterns in the presence of trend changes, the seasonal variation can be effectively identified in the time series of remote sensing data subject to various environmental changes. The experiment results performed with Landsat 5 TM data show that the decomposition results acquired for the Sonoran Desert area produce normalized series that have much less uncertainty than those

  6. Practice Guidelines for Assessing Pain in Older Persons with Dementia Residing in Long-Term Care Facilities

    PubMed Central

    Fitzgerald, Theresa Dever; Marchildon, Gregory P.

    2010-01-01

    ABSTRACT Purpose: Frail patients with dementia most frequently present with musculoskeletal pain and mobility concerns; therefore, physiotherapy interventions for this population are likely to be of great benefit. However, physiotherapists who work with older adults with dementia confront a considerable challenge: the communication impairments that characterize dementia make it difficult to assess pain and determine its source. For an effective physiotherapy programme to be implemented, valid pain assessment is necessary. This paper is intended to provide practice guidelines for pain assessment among older persons with dementia. Summary of Key Points: Over the last several years, there has been tremendous research progress in this area. While more research is needed, several promising assessment methodologies are available. These methodologies most often involve the use of observational checklists to record specific pain behaviours. Recommendations: We encourage the ongoing and regular evidence-based pain assessment of older persons with dementia, using standardized procedures. Without regular and systematic assessment, pain problems will often go undetected in this population. Given the need for systematic pain assessment and intervention for long-term care populations with mobility concerns and muculoskeletal pain problems, we call for increased involvement of physical therapists in long-term care facilities. PMID:21359040

  7. Shifting the Paradigm for Long Term Monitoring at Legacy Sites to Improve Performance while Reducing Costs - 13422

    SciTech Connect

    Eddy-Dilek, Carol A; Looney, Brian B.; Gaughan, Thomas; Kmetz, Thomas; Seaman, John

    2013-07-01

    A major issue facing many government and private industry sites that were previously contaminated with radioactive and chemical wastes is that often the sites cannot be cleaned up enough to permit unrestricted human access. These sites will require long-term management, in some cases indefinitely, leaving site owners with the challenge of protecting human health and environmental quality in a cost effective manner. Long-term monitoring of groundwater contamination is one of the largest projected costs in the life cycle of environmental management at the Savannah River Site (SRS), the larger DOE complex, and many large federal and private sites. Currently, most monitoring strategies are focused on laboratory measurements of contaminants measured in groundwater samples collected from wells. This approach is expensive, and provides limited and lagging information about the effectiveness of cleanup activities and the behavior of the residual contamination. Over the last twenty years, DOE and other federal agencies have made significant investments in the development of various types of sensors and strategies that would allow for remote analysis of contaminants in groundwater, but these approaches do not promise significant reductions in risk or cost. Scientists at SRS have developed a new paradigm to simultaneously improve the performance of long term monitoring systems while lowering the overall cost of monitoring. This alternative approach incorporates traditional point measurements of contaminant concentration with measurements of controlling variables including boundary conditions, master variables, and traditional plume/contaminant variables. Boundary conditions are the overall driving forces that control plume movement and therefore provide leading indication to changes in plume stability. These variables include metrics associated with meteorology, hydrology, hydrogeology, and land use. Master variables are the key variables that control the chemistry of the

  8. A long-term assessment of pesticide mixture effects on aquatic invertebrate communities.

    PubMed

    Hasenbein, Simone; Lawler, Sharon P; Geist, Juergen; Connon, Richard E

    2016-01-01

    To understand the potential effects of pesticide mixtures on aquatic ecosystems, studies that incorporate increased ecological relevance are crucial. Using outdoor mesocosms, the authors examined long-term effects on aquatic invertebrate communities of tertiary mixtures of commonly used pesticides: 2 pyrethroids (permethrin, λ-cyhalothrin) and an organophosphate (chlorpyrifos). Application scenarios were based on environmentally relevant concentrations and stepwise increases of lethal concentrations from 10% (LC10) to 50% (LC50) based on laboratory tests on Hyalella azteca and Chironomus dilutus; repeated applications were meant to generally reflect runoff events in a multiple-grower or homeowner watershed. Pyrethroids rapidly dissipated from the water column, whereas chlorpyrifos was detectable even 6 wk after application. Twelve of 15 macroinvertebrate and 10 of 16 zooplankton taxa responded to contaminant exposures. The most sensitive taxa were the snail Radix sp., the amphipod H. azteca, the water flea Daphnia magna, and copepods. Environmentally relevant concentrations had acute effects on D. magna and H. azteca (occurring 24 h after application), whereas lag times were more pronounced in Radix sp. snails and copepods, indicating chronic sublethal responses. Greatest effects on zooplankton communities were observed in environmentally relevant concentration treatments. The results indicate that insecticide mixtures continue to impact natural systems over multiple weeks, even when no longer detectable in water and bound to particles. Combinations of indirect and direct effects caused consequences across multiple trophic levels. PMID:26565581

  9. Long-term outcome assessment of closed treatment of mandibular fractures.

    PubMed

    Fayazi, Sara; Bayat, Mohammad; Bayat-Movahed, Saeed; Sadr-Eshkevari, Pooyan; Rashad, Ashkan

    2013-05-01

    Mandibular fractures are among the most common trauma injuries of the craniomaxillofacial region. This study evaluated the late results of mandibles fractures treated with arch bar. Forty-nine patients were examined clinically and by questionnaires for late results of arch bar treatment. Demographic data (age, sex, etc), trigeminal nerve sensation (Weber test), temporomandibular joint evaluation, masticatory muscle function, and occlusion were recorded. The data were analyzed by χ test using Sigma Stat 2.0 software. Fifty-one percent of the patients with angular fractures complained of sensory disturbances. Condylar and angular fractures demonstrated higher levels of pain. According to Pearson χ test, a statistically significant relation between angular fracture and tenderness of the internal pterygoid muscles (P = 0.047), angular fracture and cross-bite (P = 0.021), parasymphysial fracture and pain upon wind blowing (P = 0.026), and body fracture and mastication discomfort (P = 0.038) was found. In closed reduction therapy, fracture location of the mandible seems to be more likely correlated in producing particular long-term complications. Regular follow-ups for functional treatments and physiotherapy of chewing muscles and temporomandibular joint, along with removal of occlusal abnormalities, should be considered following arch bar reduction of mandibular fractures. PMID:23714869

  10. Assessing the Long-Term System Value of Intermittent Electric Generation Technologies

    SciTech Connect

    Lamont, A D

    2005-08-24

    This research investigates the economic penetration and system-wide effects of large-scale intermittent technologies in an electric generation system. The research extends the standard screening curve analysis to optimize the penetration and system structure with intermittent technologies. The analysis is based on hour-by-hour electric demands and intermittent generation. A theoretical framework is developed to find an expression for the marginal value of an intermittent technology as a function of the average system marginal cost, the capacity factor of the generator, and the covariance between the generator's hourly production and the hourly system marginal cost. A series of model runs are made examining the penetration of wind and photovoltaic in a simple electric generation system. These illustrate the conclusions in the theoretical analysis and illustrate the effects that large-scale intermittent penetration has on the structure of the generation system. In the long-term, adding intermittent generation to a system allows us to restructure the dispatchable generation capacity to a mix with lower capital cost. It is found that large scale intermittent generation tends to reduce the optimal capacity and production of baseload generators and increase the capacity and production of intermediate generators, although the extent to which this occurs depends strongly on the pattern of production from the intermediate generators. It is also shown that the marginal value of intermittent generation declines as it penetrates. The analysis investigates the specific mechanism through which this occurs.