Science.gov

Sample records for barrier systems assessment

  1. Assessment of engineered barrier system and design of waste packages

    SciTech Connect

    Ramspott, L.D.

    1988-06-01

    The US Nuclear Regulatory Commission has established two post-closure performance objectives for the Engineered Barrier System (EBS) in a geologic repository. These require containment of the waste followed by controlled release. The EBS for a repository in unsaturated tuff at Yucca Mountain is designed to meet these performance objectives. The major components are the waste form, container, air gap, and borehole liner. Assessment of post-closure performance of the EBS is based on allocating performance for various components toward meeting overall design objectives. Because of the unprecedented time periods considered, 1000 to 10,000 years, computer modeling is essential and will be used in conjunction with testing to assess whether the performance allocations are met. 7 refs., 1 tab.

  2. Status of integrated performance assessment of the waste packages and engineered barrier system

    SciTech Connect

    O`Connell, W.J.

    1990-01-01

    Performance assessment of the engineered barrier system for a nuclear waste repository combines information from relevant disciplines and predicts the net long-term performance of the EBS in unites of regulatory goals for performance. The performance assessment models are specific to the proposed Yucca Mountain, Nevada site. Early assessments are used for project planning and feedback. The EBS scenarios activity develops the scenarios and the consequent event sequences. Initial model development for single waste packages indicates that the radionuclide release rate performance is sensitive to the water flux, element solubilities, and/or the mode of water contact with the waste. The latter in turn depends on local scale hydrology and the modes of corrosion for the container material. For the release rate summed over waste packages, variations among waste packages and their near-field environments are anticipated. These variations place demands on data acquisition and modeling, as well as modulate the impact of localized changes of conditions. Sampling in uncertainty assessment is a subsequent step in examining the reliability of predictions made in the performance assessments. Advances made in sampling methods are referenced. 14 refs., 6 figs.

  3. Vehicle barrier systems

    SciTech Connect

    Sena, P.A.

    1986-01-01

    The ground vehicle is one of the most effective tools available to an adversary force. Vehicles can be used to penetrate many types of perimeter barriers, transport equipment and personnel rapidly over long distances, and deliver large amounts of explosives directly to facilities in suicide missions. The function of a vehicle barrier system is to detain or disable a defined threat vehicle at a selected distance from a protected facility. Numerous facilities are installing, or planning to install, vehicle barrier systems and many of these facilities are requesting guidance to do so adequately. Therefore, vehicle barriers are being evaluated to determine their stopping capabilities so that systems can be designed that are both balanced and capable of providing a desired degree of protection. Equally important, many of the considerations that should be taken into account when establishing a vehicle barrier system have been identified. These considerations which pertain to site preparation, barrier selection, system integration and operation, and vehicle/barrier interaction, are discussed in this paper. 2 tabs.

  4. Vehicle barrier systems

    SciTech Connect

    Sena, P.A.

    1986-01-01

    The ground vehicle is one of the most effective tools available to an adversary force. Vehicles can be used to penetrate many types of perimeter barriers, transport equipment, and personnel rapidly over long distances, and deliver large amounts of explosives directly to facilities in suicide missions. The function of a vehicle barrier system is to detain or disable a defined threat vehicle at a selected distance from a protected facility. Numerous facilities are installing, or planning to install, vehicle barrier systems and many of these facilities are requesting guidance to do so adequately. Therefore, vehicle barriers are being evaluated to determine their stopping capabilities so that systems can be designed that are both balanced and capable of providing a desired degree of protection. Equally important, many of the considerations that should be taken into account when establishing a vehicle barrier system have been identified. These considerations which pertain to site preparation, barrier selection, system integration and operation, and vehicle/barrier interaction, are discussed in this paper.

  5. Vehicle barrier systems

    SciTech Connect

    Sena, P.A.

    1986-01-01

    The ground vehicle is one of the most effective tools available to an adversary force. Vehicles can be used to penetrate many types of perimeter barriers, transport equipment and personnel rapidly over long distances, and deliver large amounts of explosives directly to facilities in suicide missions. The function of a vehicle barrier system is to detain or disable a defined threat vehicle at a selected distance from a protected facility. Numerous facilities are installing, or planning to install, vehicle barrier systems and many of these facilities are requesting guidance to do so adequately. Therefore, vehicle barriers are being evaluated to determine their stopping capabilities so that systems can be designed that are both balanced and capable of providing a desired degree of protection. Equally important, many of the considerations that should be taken into account when establishing a vehicle barrier system have been identified. These considerations which pertain to site preparation, barrier selection, system integration and operation, and vehicle/barrier interaction, are discussed in this paper.

  6. Vehicle barrier systems

    SciTech Connect

    Sena, P.A.

    1986-01-01

    The ground vehicle is one of the most effective tools available to an adversary force. Vehicles can be used to penetrate many types of perimeter barriers, transport equipment and personnel rapidly over long distances, and deliver large amounts of explosives directly to facilities in suicide missions. The function of a vehicle barrier system is to detain or disable a defined threat vehicle at a selected distance from a protected facility. Numerous facilities are installing, or planning to install, vehicle barrier systems and many of these facilities are requesting guidance to do so adequately. Therefore, vehicle barriers are being evaluated to determine their stopping capabilities so that systems can be designed that are both balanced and capable of providing a desired degree of protection. Equally important, many of the considerations that should be taken into account when establishing a vehicle barrier system have been identified. These considerations which pertain to site preparation, barrier selection, system integration and operation, and vehicle/barrier interaction, are discussed in this paper. 2 tabs.

  7. Geophysical Assessment of the Control of a Jetty on a Barrier Beach and Estuary System

    NASA Astrophysics Data System (ADS)

    Ulrich, C.; Hubbard, S.; Delaney, C.; Seymour, D.; Blom, K.; Black, W.

    2013-12-01

    An evaluation is underway at the Goat Rock State Beach, which is located at the mouth of the Russian River near Jenner, CA. The study focuses on quantifying the influence of a man made jetty on the functioning of a barrier beach and associated implications for estuary fish habitat and flood control. Flow through the beach results from water level differences between the estuary and the ocean. When the estuary is closed or perched, one of the potential major sources of outflow from the lagoon is seepage flow through the barrier beach. The location and design of the jetty could be altering subsurface flow paths through the jetty and possibly impeding or enhancing subsurface flow where the jetty is still intact. This will result in unnatural connectivity between the ocean and the estuary leading to atypical surface water elevations and possibly salinity imbalance. Results of the assessment will enable the Sonoma County Water Agency to understand how the jetty affects formation of the barrier beach and water surface elevations within the estuary. As one aspect of the evaluation, we are using geophysical methods to monitor seepage through the jetty as well as through the beach berm. We are using multiple surface geophysical methods, including: electrical resistivity, seismic refraction, ground penetrating radar, and electromagnetic methods. In general, seismic data are being used to characterize deeper bedrock controls on beach barrier functioning such as, channeling of estuarine water beneath the barrier beach. Electrical and electromagnetic methods are being used to characterize the beach sediment layers that could contribute to preferential flow paths during tide cycles in addition to preferential flow paths created by the jetty structure. Time-lapse electrical and electromagnetic data are being used to monitor moisture changes and mixing of saline and fresh water within the beach berm. Ground penetrating radar data are being used to delineate the geometry of the

  8. Thermal barrier coating system

    NASA Technical Reports Server (NTRS)

    Stecura, S.; Leibert, C. H. (Inventor)

    1977-01-01

    A coating system which contains a bond coating and a thermal barrier coating is applied to metal surfaces such as turbine blades and provides both low thermal conductivity and improved adherence when exposed to high temperature gases or liquids. The bond coating contains NiCrAlY and the thermal barrier coating contains a reflective oxide. The reflective oxides ZrO2-Y2O3 and ZrO2-MgO have demonstrated significant utility in high temperature turbine applications.

  9. Thermal barrier coating system

    NASA Technical Reports Server (NTRS)

    Stecura, S. (Inventor)

    1984-01-01

    A high temperature oxidation resistant, thermal barrier coating system is disclosed for a nickel cobalt, or iron base alloy substrate. An inner metal bond coating contacts the substrate, and a thermal barrier coating covers the bond coating. NiCrAlR, FeCrAlR, and CoCrAlR alloys are satisfactory as bond coating compositions where R=Y or Yb. These alloys contain, by weight, 24.9-36.7% chromium, 5.4-18.5% aluminum, and 0.05 to 1.55% yttrium or 0.05 to 0.53% ytterbium. The coatings containing ytterbium are preferred over those containing yttrium. An outer thermal barrier coating of partial stabilized zirconium oxide (zirconia) which is between 6% and 8%, by weight, of yttrium oxide (yttria) covers the bond coating. Partial stabilization provides a material with superior durability. Partially stabilized zirconia consists of mixtures of cubic, tetragonal, and monoclinic phases.

  10. Geophysical Assessment of the Control of a Jetty on a Barrier Beach and Estuary System

    NASA Astrophysics Data System (ADS)

    Ulrich, C.; Hubbard, S. S.; Peterson, J.; Blom, K.; Black, W.; Delaney, C.; Mendoza, J.

    2014-12-01

    An evaluation is underway at the Goat Rock State Park, located at the mouth of the Russian River near Jenner, CA, to quantify the influence of a man made jetty on the functioning of a barrier beach and associated implications for estuary fish habitat and flood control. Flow through the beach results from water level differences between the estuary and the ocean. When the estuary is closed or perched, one of the major sources of outflow from the lagoon is seepage flow through the barrier beach. The location and design of the jetty could be altering subsurface flow paths through the jetty and possibly impeding subsurface flow where the jetty is still intact. This will result in unnatural connectivity between the ocean and the estuary leading to atypical surface water elevations and possibly salinity imbalance. We are monitoring seepage through the jetty and beach berm with multiple surface and borehole geophysical methods, including: electrical resistivity (ERT), seismic refraction (SR), ground penetrating radar (GPR), and electromagnetic methods (EM). We use SR data to characterize deeper bedrock controls on beach barrier functioning; ERT and EM methods to characterize the beach sediment layers that could contribute to preferential flow paths during tide cycles in addition to preferential flow paths created by the jetty structure; time-lapse ERT and EM data to monitor moisture changes and mixing of saline and fresh water within the beach berm, and borehole ERT and GPR data to delineate the geometry of the (often buried) jetty. Preliminary ERT and EM results indicate two preferential flow paths through zones of missing jetty structure, while time-lapse borehole ERT data is expected to image saltwater flow impedance in zones of intact jetty structure. All data are being integrated with topography, tidal, borehole, and hydrological information and the results of the assessment will enable the Sonoma County Water Agency to develop the feasibility of alternatives to the

  11. Assessing the use of poplar tree systems as a landfill evapotranspiration barrier with the SHAW model.

    PubMed

    Preston, G M; McBride, R A

    2004-08-01

    The use of poplar tree systems (PTS) as evapotranspiration barriers on decommissioned landfills is gaining attention as an option for leachate management. This study involved field-testing the Simultaneous Heat and Water (SHAW) model for its ability to reliably estimate poplar transpiration, volumetric soil water content, and soil temperature at a landfill located in southern Ontario, Canada. The model was then used to estimate deep drainage and to ascertain the influence of a young PTS on the soil water balance of the landfill cover. The SHAW model tended to underestimate poplar transpiration [mean difference (MD) ranged from 0.33 to 3.55 mm on a daily total basis] and overestimate volumetric soil water content by up to 0.10 m3 m(-3). The model estimated soil temperature very well, particularly in the upper 1 m of the landfill cover (MD ranged from -0.1 to 1.6 x degrees C in this layer). The SHAW model simulations showed that deep drainage decreased appreciably with the presence of a young PTS largely through increased interception of rainfall, and that PTS have a good potential to act as effective evapotranspiration barriers in northern temperate climate zones.

  12. Multilayer thermal barrier coating systems

    DOEpatents

    Vance, Steven J.; Goedjen, John G.; Sabol, Stephen M.; Sloan, Kelly M.

    2000-01-01

    The present invention generally describes multilayer thermal barrier coating systems and methods of making the multilayer thermal barrier coating systems. The thermal barrier coating systems comprise a first ceramic layer, a second ceramic layer, a thermally grown oxide layer, a metallic bond coating layer and a substrate. The thermal barrier coating systems have improved high temperature thermal and chemical stability for use in gas turbine applications.

  13. Thermal barrier coating system

    NASA Technical Reports Server (NTRS)

    Stecura, S. (Inventor)

    1985-01-01

    An oxide thermal barrier coating comprises ZrO3-Yb2O3 that is plasma sprayed onto a previously applied bond coating. The zirconia is partially stabilized with about 124 w/o ytterbia to insure cubic, monoclinic, and terragonal phases.

  14. Infection control at an urban hospital in Manila, Philippines: a systems engineering assessment of barriers and facilitators.

    PubMed

    Mitchell, Kaitlin F; Barker, Anna K; Abad, Cybele L; Safdar, Nasia

    2017-01-01

    Healthcare facilities in low- and middle-income countries, including the Philippines, face substantial challenges in achieving effective infection control. Early stages of interventions should include efforts to understand perceptions held by healthcare workers who participate in infection control programs. We performed a qualitative study to examine facilitators and barriers to infection control at an 800-bed, private, tertiary hospital in Manila, Philippines. Semi-structured interviews were conducted with 22 nurses, physicians, and clinical pharmacists using a guide based on the Systems Engineering Initiative for Patient Safety (SEIPS). Major facilitators and barriers to infection control were reported for each SEIPS factor: person, organization, tasks, physical environment, and technology and tools. Primary facilitators included a robust, long-standing infection control committee, a dedicated infection control nursing staff, and innovative electronic hand hygiene surveillance technology. Barriers included suboptimal dissemination of hand hygiene compliance data, high nursing turnover, clinical time constraints, and resource limitations that restricted equipment purchasing. The identified facilitators and barriers may be used to prioritize possible opportunities for infection control interventions. A systems engineering approach is useful for conducting a comprehensive work system analysis, and maximizing resources to overcome known barriers to infection control in heavily resource-constrained settings.

  15. Systems study on engineered barriers: barrier performance analysis

    SciTech Connect

    Stula, R.T.; Albert, T.E.; Kirstein, B.E.; Lester, D.H.

    1980-09-01

    A performance assessment model for multiple barrier packages containing unreprocessed spent fuel has been modified and applied to several package designs. The objective of the study was to develop information to be used in programmatic decision making concerning engineered barrier package design and development. The assessment model, BARIER, was developed in previous tasks of the System Study on Engineered Barriers (SSEB). The new version discussed in this report contains a refined and expanded corrosion rate data base which includes pitting, crack growth, and graphitization as well as bulk corrosion. Corrosion rates for oxic and anoxic conditions at each of the two temperature ranges are supplied. Other improvements include a rigorous treatment of radionuclide release after package failure which includes resistance of damaged barriers and backfill, refined temperature calculations that account for convection and radiation, a subroutine to calculate nuclear gamma radiation field at each barrier surface, refined stress calculations with reduced conservatism and various coding improvements to improve running time and core usage. This report also contains discussion of alternative scenarios to the assumed flooded repository as well as the impact of water exclusion backfills. The model was used to assess post repository closure performance for several designs which were all variation of basic designs from the Spent Unreprocessed Fuel (SURF) program. Many designs were found to delay the onset of leaching by at least a few hundreds of years in all geologic media. Long delay times for radionuclide release were found for packages with a few inches of sorption backfill. Release of uranium, plutonium, and americium was assessed.

  16. Stimulated Recall Methodology for Assessing Work System Barriers and Facilitators in Family-Centered Rounds in a Pediatric Hospital

    PubMed Central

    Carayon, Pascale; Li, Yaqiong; Kelly, Michelle M.; DuBenske, Lori L.; Xie, Anping; McCabe, Brenna; Orne, Jason; Cox, Elizabeth D.

    2014-01-01

    Human factors and ergonomics methods are needed to redesign healthcare processes and support patient-centered care, in particular for vulnerable patients such as hospitalized children. We implemented and evaluated a stimulated recall methodology for collective confrontation in the context of family-centered rounds. Five parents and five healthcare team members reviewed video records of their bedside rounds, and were then interviewed using the stimulated recall methodology to identify work system barriers and facilitators in family-centered rounds. The evaluation of the methodology was based on a survey of the participants, and a qualitative analysis of interview data in light of the work system model of Smith and Carayon (1989; 2000). Positive survey feedback from the participants was received. The stimulated recall methodology identified barriers and facilitators in all work system elements. Participatory ergonomics methods such as the stimulated recall methodology allow a range of participants, including parents and children, to participate in healthcare process improvement. PMID:24894378

  17. Stimulated recall methodology for assessing work system barriers and facilitators in family-centered rounds in a pediatric hospital.

    PubMed

    Carayon, Pascale; Li, Yaqiong; Kelly, Michelle M; DuBenske, Lori L; Xie, Anping; McCabe, Brenna; Orne, Jason; Cox, Elizabeth D

    2014-11-01

    Human factors and ergonomics methods are needed to redesign healthcare processes and support patient-centered care, in particular for vulnerable patients such as hospitalized children. We implemented and evaluated a stimulated recall methodology for collective confrontation in the context of family-centered rounds. Five parents and five healthcare team members reviewed video records of their bedside rounds, and were then interviewed using the stimulated recall methodology to identify work system barriers and facilitators in family-centered rounds. The evaluation of the methodology was based on a survey of the participants, and a qualitative analysis of interview data in light of the work system model of Smith and Carayon (1989, 2001). Positive survey feedback from the participants was received. The stimulated recall methodology identified barriers and facilitators in all work system elements. Participatory ergonomics methods such as the stimulated recall methodology allow a range of participants, including parents and children, to participate in healthcare process improvement.

  18. Engineered Barrier System: Physical and Chemical Environment

    SciTech Connect

    P. Dixon

    2004-04-26

    The conceptual and predictive models documented in this Engineered Barrier System: Physical and Chemical Environment Model report describe the evolution of the physical and chemical conditions within the waste emplacement drifts of the repository. The modeling approaches and model output data will be used in the total system performance assessment (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. These models evaluate the range of potential water compositions within the emplacement drifts, resulting from the interaction of introduced materials and minerals in dust with water seeping into the drifts and with aqueous solutions forming by deliquescence of dust (as influenced by atmospheric conditions), and from thermal-hydrological-chemical (THC) processes in the drift. These models also consider the uncertainty and variability in water chemistry inside the drift and the compositions of introduced materials within the drift. This report develops and documents a set of process- and abstraction-level models that constitute the engineered barrier system: physical and chemical environment model. Where possible, these models use information directly from other process model reports as input, which promotes integration among process models used for total system performance assessment. Specific tasks and activities of modeling the physical and chemical environment are included in the technical work plan ''Technical Work Plan for: In-Drift Geochemistry Modeling'' (BSC 2004 [DIRS 166519]). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system analysis model reports.

  19. Assessment study for multi-barrier system used in radioactive borate waste isolation based on Monte Carlo simulations.

    PubMed

    Bayoumi, T A; Reda, S M; Saleh, H M

    2012-01-01

    Radioactive waste generated from the nuclear applications should be properly isolated by a suitable containment system such as, multi-barrier container. The present study aims to evaluate the isolation capacity of a new multi-barrier container made from cement and clay and including borate waste materials. These wastes were spiked by (137)Cs and (60)Co radionuclides to simulate that waste generated from the primary cooling circuit of pressurized water reactors. Leaching of both radionuclides in ground water was followed and calculated during ten years. Monte Carlo (MCNP5) simulations computed the photon flux distribution of the multi-barrier container, including radioactive borate waste of specific activity 11.22KBq/g and 4.18KBq/g for (137)Cs and (60)Co, respectively, at different periods of 0, 15.1, 30.2 and 302 years. The average total flux for 100cm radius of spherical cell was 0.192photon/cm(2) at initial time and 2.73×10(-4)photon/cm(2) after 302 years. Maximum waste activity keeping the surface radiation dose within the permissible level was calculated and found to be 56KBq/g with attenuation factors of 0.73cm(-1) and 0.6cm(-1) for cement and clay, respectively. The average total flux was 1.37×10(-3)photon/cm(2) after 302 years. Monte Carlo simulations revealed that the proposed multi-barrier container is safe enough during transportation, evacuation or rearrangement in the disposal site for more than 300 years.

  20. Model assessment of protective barriers: Part 3

    SciTech Connect

    Fayer, M.J.; Rockhold, M.L.; Holford, D.J.

    1992-02-01

    Radioactive waste exists at the US Department of Energy's (DOE's) Hanford Site in a variety of locations, including subsurface grout and tank farms, solid waste burial grounds, and contaminated soil sites. Some of these waste sites may need to be isolated from percolating water to minimize the potential for transport of the waste to the ground water, which eventually discharges to the Columbia River. Multilayer protective barriers have been proposed as a means of limiting the flow of water through the waste sites (DOE 1987). A multiyear research program (managed jointly by Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company for the DOE) is aimed at assessing the performance of these barriers. One aspect of this program involves the use of computer models to predict barrier performance. Three modeling studies have already been conducted and a test plan was produced. The simulation work reported here was conducted by PNL and extends the previous modeling work. The purpose of this report are to understand phenomena that have been observed in the field and to provide information that can be used to improve hydrologic modeling of the protective barrier. An improved modeling capability results in better estimates of barrier performance. Better estimates can be used to improve the design of barriers and the assessment of their long-term performance.

  1. ENGINEERED BARRIER SYSTEM: PHYSICAL AND CHEMICAL ENVIRONMENT

    SciTech Connect

    G.H. Nieder-Westermann

    2005-04-07

    The purpose of this report is to describe the evolution of the physical and chemical environmental conditions within the waste emplacement drifts of the repository, including the drip shield and waste package surfaces. The abstraction model is used in the total system performance assessment for the license application (TSPA LA) to assess the performance of the engineered barrier system and the waste form. This report develops and documents a set of these abstraction-level models that describe the engineered barrier system physical and chemical environment. Where possible, these models use information directly from other reports as input, which promotes integration among process models used for TSPA-LA. Specific tasks and activities of modeling the physical and chemical environment are included in ''Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration'' (BSC 2004 [DIRS 171156], Section 1.2.2). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system reports.

  2. ENGINEERED BARRIER SYSTEM: PHYSICAL AND CHEMICAL ENVIRONMENT

    SciTech Connect

    R. Jarek

    2004-11-23

    The purpose of this report is to describe the evolution of the physical and chemical environmental conditions within the waste emplacement drifts of the repository, including the drip shield and waste package surfaces. The abstraction model is used in the total system performance assessment for the license application (TSPA LA) to assess the performance of the engineered barrier system and the waste form. This report develops and documents a set of these abstraction-level models that describe the engineered barrier system physical and chemical environment. Where possible, these models use information directly from other reports as input, which promotes integration among process models used for TSPA-LA. Specific tasks and activities of modeling the physical and chemical environment are included in ''Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration'' (BSC 2004 [DIRS 171156], Section 1.2.2). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system reports.

  3. Advanced thermal barrier coating systems

    NASA Technical Reports Server (NTRS)

    Dorfman, M. R.; Reardon, J. D.

    1985-01-01

    Current state-of-the-art thermal barrier coating (TBC) systems consist of partially stabilized zirconia coatings plasma sprayed over a MCrAlY bond coat. Although these systems have excellent thermal shock properties, they have shown themselves to be deficient for a number of diesel and aircraft applications. Two ternary ceramic plasma coatings are discussed with respect to their possible use in TBC systems. Zirconia-ceria-yttria (ZCY) coatings were developed with low thermal conductivities, good thermal shock resistance and improved resistance to vanadium containing environments, when compared to the baseline yttria stabilized zirconia (YSZ) coatings. In addition, dense zirconia-titania-yttria (ZTY) coatings were developed with particle erosion resistance exceeding conventional stabilized zirconia coatings. Both coatings were evaluated in conjunction with a NiCr-Al-Co-Y2O3 bond coat. Also, multilayer or hybrid coatings consisting of the bond coat with subsequent coatings of zirconia-ceria-yttria and zirconia-titania-yttria were evaluated. These coatings combine the enhanced performance characteristics of ZCY with the improved erosion resistance of ZTY coatings. Improvement in the erosion resistance of the TBC system should result in a more consistent delta T gradient during service. Economically, this may also translate into increased component life simply because the coating lasts longer.

  4. Model assessment of protective barrier designs: Part 2

    SciTech Connect

    Fayer, M.J.

    1987-11-01

    Protective barriers are being considered for use at the Hanford Site to enhance the isolation of radioactive wastes from water, plant, and animal intrusion. This study assesses the effectiveness of protective barriers for isolation of wastes from water. In this report, barrier designs are reviewed and several barrier modeling assumptions are tested. 20 refs., 16 figs., 6 tabs.

  5. Teamwork on inpatient medical units: assessing attitudes and barriers.

    PubMed

    O'Leary, K J; Ritter, C D; Wheeler, H; Szekendi, M K; Brinton, T S; Williams, M V

    2010-04-01

    Discrepant attitudes about teamwork among nurses and physicians exist in operating rooms and intensive care units. Little is known about teamwork attitudes on general medical services. To assess ratings of teamwork by providers on inpatient medical units and barriers to collaboration. Nurses, primary hospital physicians and medical subspeciality consultants on four general medical units were surveyed. Providers rated the quality of communication and collaboration experienced with their own and other disciplines. Providers also rated potential barriers to collaboration. Differences between providers in ratings of collaboration and barriers were tested using analysis of variance. Of 230 eligible providers, 159 (69%) completed the survey. Teamwork ratings of nurses were similarly high across provider types. Ratings of physicians differed considerably by provider type (pbarriers to interdisciplinary communication to be difficulty identifying patients' providers and their roles. Primary hospital physicians rated not having physicians and nurses on a single telecommunication system as the biggest barrier. In a general medical inpatient setting, discrepancies among nurses and physicians existed in ratings of collaboration and barriers to teamwork. Whereas physicians rated the quality of teamwork with nurses favourably, nurses perceived teamwork as suboptimal.

  6. Metallic seal for thermal barrier coating systems

    NASA Technical Reports Server (NTRS)

    Miller, Robert A. (Inventor)

    1990-01-01

    The invention is particularly concerned with sealing thermal barrier coating systems of the type in use and being contemplated for use in diesel and other internal combustion engines. The invention also would find application in moderately high temperature regions of gas turbine engines and any other application employing a thermal barrier coating at moderate temperatures. Ni-35Cr-6Al-1Y, Ni-35Cr-6Al-1Yb, or other metallic alloy denoted as MCrAlx is applied over a zirconia-based thermal barrier overlayer. The close-out layer is glass-bead preened to densify its surface. This seals and protects the thermal barrier coating system.

  7. A Survey to Assess Barriers to Urban Teaching Careers

    ERIC Educational Resources Information Center

    Creasey, Gary; Mays, Jennifer; Lee, Robert; D'Santiago, Verenice

    2016-01-01

    The "Urban Teaching Barriers" survey was created to assess barriers to urban teaching careers. Pre-service teachers (N = 377) completed this instrument, along with questionnaires that assessed urban teaching intentions and urban teaching self-efficacy. Six barrier domains were identified that tapped concerns over (a) lack of resources,…

  8. A Survey to Assess Barriers to Urban Teaching Careers

    ERIC Educational Resources Information Center

    Creasey, Gary; Mays, Jennifer; Lee, Robert; D'Santiago, Verenice

    2016-01-01

    The "Urban Teaching Barriers" survey was created to assess barriers to urban teaching careers. Pre-service teachers (N = 377) completed this instrument, along with questionnaires that assessed urban teaching intentions and urban teaching self-efficacy. Six barrier domains were identified that tapped concerns over (a) lack of resources,…

  9. SUBSURFACE BARRIER VALIDATION WITH THE SEAFACE SYSTEM

    SciTech Connect

    Sandra Dalvit Dunn

    1997-11-30

    The overall objective of the effort was to develop and demonstrate an integrated methodology and field system to evaluate the integrity of in situ, impermeable barriers constructed in the vadose zone. An autonomous, remotely accessible, automatic monitoring and analysis system was designed and fabricated. It was thoroughly tested under field conditions, and was able to function as designed throughout the test period. Data inversion software was developed with enhanced capabilities over the previous prototype version, and integrated with the monitoring system for real time operation. Analytical simulations were performed to determine the inversion code's sensitivity to model parameters. Numerical simulations were performed to better understand how typical field conditions differ from the ideal model(s) which are used (or have been developed for use) in the inversion code and to further validate the flux limited forward model developed for use with the system. Results from the analytical and numerical assessment of the inversion code showed that the SEAtrace{trademark} approach could locate leaks within 0.4 to 1.2 m. Leak size determination was less accurate, but produced results within a factor of 3 to 8 for leaks in the 2.5 to 10 cm diameter range. The smallest engineered leak in the test 1.1 cm diameter, could be located but its size estimate was high by a factor of 30. Data analysis was performed automatically after each gas scan was completed, yielding results in less than thirty minutes, although the bulk of the results reported required post test data analysis to remove effects of high background concentrations. The field test of the integrated system was problematic, primarily due to unanticipated, unintentional leaks formed in the impermeable liner. The test facility constructed to proof the system was ambitious, initially having 11 engineered leaks of various dimensions that could be independently operated. While a great deal of care went into the

  10. PS2-47: Systematic Stakeholder Assessment to Determine Facilitators of and Barriers to SBIRT Implementation in Multiple Integrated Health Systems

    PubMed Central

    Rahm, Alanna Kulchak; Boggs, Jennifer; Martin, Carmen; Beck, Arne; Pearson, Marilyn; Backer, Thomas; Ahmedani, Brian

    2014-01-01

    Background/Aims The US Preventive Services Task Force has identified alcohol and drug use screening as a high priority in primary care. SBIRT is a framework for population based screening and brief intervention with the goal of reducing substance use before it progresses to dependence. There has been limited uptake of SBIRT in any large health system, thus SAMHSA has supported a series of studies, led by Kaiser Permanente Colorado (KPCO), to determine strategies to promote large scale SBIRT implementation. Methods A qualitative examination of SBIRT feasibility and subsequent pilot testing within KPCO primary care guided a series of additional stakeholder interviews at Henry Ford Health System (HFHS) to assess feasibility of SBIRT implementation in additional organizations. Qualitative interviews were conducted with a broad spectrum of HFHS stakeholders using snowball sampling. A total of 28 HFHS stakeholders were interviewed. Interviews were conducted telephonically by trained interviewers from KPCO and lasted approximately 30 minutes. Interviews were digitally recorded and transcribed. After each interview, a detailed summary was generated and used to create the initial code book for analysis of interview transcripts. Results While current screening, brief intervention, and referral to treatment processes for substance use were noted in HFHS, they were inconsistent and no systematic policies exist. Many facilitators for SBIRT implementation within HFHS were noted including: population, recent implementation of depression screening in primary care, and EMR tools to facilitate documentation. Barriers to SBIRT implementation included time and competing demands for primary care providers, access to treatment, and follow-up processes for positive screens. All stakeholders were supportive of pilot implementation of SBIRT within HFHS with adequate attention to barriers and facilitators. Conclusions This project successfully demonstrated the value of gaining stakeholder

  11. Estuarine shoreline and barrier-island sandline change assessment

    USGS Publications Warehouse

    Terrano, Joseph F.; Smith, Kathryn E.L.

    2016-01-01

    The Barrier Island and Estuarine Wetland Physical Change Assessment Dataset was created to calibrate and test probability models of barrier island sandline and estuarine shoreline change for study areas in Virginia, Maryland, and New Jersey. The models examined the influence of hydrologic and physical variables related to storm-derived overwash and estuarine shoreline change. Variables were calculated using a transect-based method in a geographic information system (GIS) by creating shoreline-perpendicular lines at regular intervals along the oceanfront shoreline and extrapolating the features from geospatial data, including lidar, bathymetry and aerial imagery. In addition, the data set provides storm-derived barrier island change for Hurricane Sandy, as well as linear rates of change for long-term sandline and estuarine shorelines.

  12. HRE-Pond Cryogenic Barrier Technology Demonstration: Pre- and Post-Barrier Hydrologic Assessment

    SciTech Connect

    Moline, G.R.

    1999-06-01

    The Homogeneous Reactor Experiment (HRE) Pond is the site of a former impoundment for radioactive wastes on the Oak Ridge Reservation (ORR) in east Tennessee. The pond received radioactive wastes from 1957 to 1962, and was subsequently drained, filled with soil, and covered with an asphalt cap. The site is bordered to the east and south by an unnamed stream that contains significant concentrations of radioactive contaminants, primarily {sup 90}Sr. Because of the proximity of the stream to the HRE disposal site and the probable flow of groundwater from the site to the stream, it was hypothesized that the HRE Pond has been a source of contamination to the creek. The HRE-Pond was chosen as the site of a cryogenic barrier demonstration to evaluate this technology as a means for rapid, temporary isolation of contaminants in the type of subsurface environment that exists on the ORR. The cryogenic barrier is created by the circulation of liquid CO{sub 2} through a system of thermoprobes installed in boreholes which are backfilled with sand. The probes cool the subsurface, creating a vertical ice wall by freezing adjacent groundwater, effectively surrounding the pond on four sides. The purpose of this investigation was to evaluate the hydrologic conditions within and around the pond prior to, during, and after the cryogenic barrier emplacement. The objectives were (1) to provide a hydrologic baseline for post-banner performance assessment, (2) to confirm that the pond is hydraulically connected to the surrounding sediments, (3) to determine the likely contaminant exit pathways from the pond, and (4) to measure changes in hydrologic conditions after barrier emplacement in order to assess the barrier performance. Because relatively little information about the subsurface hydrology and the actual configuration of the pond existed, data from multiple sources was required to reconstruct this complex system.

  13. Double barrier system for an in situ conversion process

    DOEpatents

    McKinzie, Billy John [Houston, TX; Vinegar, Harold J [Bellaire, TX; Cowan, Kenneth Michael [Sugar land, TX; Deeg, Wolfgang Friedrich Johann [Houston, TX; Wong, Sau-Wai [Rijswijk, NL

    2009-05-05

    A barrier system for a subsurface treatment area is described. The barrier system includes a first barrier formed around at least a portion of the subsurface treatment area. The first barrier is configured to inhibit fluid from exiting or entering the subsurface treatment area. A second barrier is formed around at least a portion of the first barrier. A separation space exists between the first barrier and the second barrier.

  14. ENGINEERED BARRIER SYSTEM: PHYSICAL AND CHEMICAL ENVIRONMENT

    SciTech Connect

    R. Jarek

    2005-08-29

    The purpose of this model report is to describe the evolution of the physical and chemical environmental conditions within the waste emplacement drifts of the repository, including the drip shield and waste package surfaces. The resulting seepage evaporation and gas abstraction models are used in the total system performance assessment for the license application (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. This report develops and documents a set of abstraction-level models that describe the engineered barrier system physical and chemical environment. Where possible, these models use information directly from other reports as input, which promotes integration among process models used for TSPA-LA. Specific tasks and activities of modeling the physical and chemical environment are included in ''Technical Work Plan for: Near-Field Environment and Transport In-Drift Geochemistry Model Report Integration'' (BSC 2005 [DIRS 173782], Section 1.2.2). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system reports. To be consistent with other project documents that address features, events, and processes (FEPs), Table 6.14.1 of the current report includes updates to FEP numbers and FEP subjects for two FEPs identified in the technical work plan (TWP) governing this report (BSC 2005 [DIRS 173782]). FEP 2.1.09.06.0A (Reduction-oxidation potential in EBS), as listed in Table 2 of the TWP (BSC 2005 [DIRS 173782]), has been updated in the current report to FEP 2.1.09.06.0B (Reduction-oxidation potential in Drifts; see Table 6.14-1). FEP 2.1.09.07.0A (Reaction kinetics in EBS), as listed in Table 2 of the TWP (BSC 2005 [DIRS 173782]), has been updated in the current report to FEP 2.1.09.07.0B (Reaction kinetics in Drifts; see Table 6.14-1). These deviations from the TWP are justified because they improve integration with FEPs documents. The updates

  15. Assessing To Address Barriers to Learning. An Introductory Packet.

    ERIC Educational Resources Information Center

    California Univ., Los Angeles. Center for Mental Health Schools.

    Schools committed to the success of all children must have an array of activities designed to address barriers to learning. This introductory packet contains some aids to help school staff find new ways of thinking about how schools should assess barriers to learning. The following items are included in the packet: (1) a chart of "Barriers to…

  16. Vapor-barrier Vacuum Isolation System

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M. (Inventor); Taminger, Karen M. (Inventor)

    2014-01-01

    A system includes a collimated beam source within a vacuum chamber, a condensable barrier gas, cooling material, a pump, and isolation chambers cooled by the cooling material to condense the barrier gas. Pressure levels of each isolation chamber are substantially greater than in the vacuum chamber. Coaxially-aligned orifices connect a working chamber, the isolation chambers, and the vacuum chamber. The pump evacuates uncondensed barrier gas. The barrier gas blocks entry of atmospheric vapor from the working chamber into the isolation chambers, and undergoes supersonic flow expansion upon entering each isolation chamber. A method includes connecting the isolation chambers to the vacuum chamber, directing vapor to a boundary with the working chamber, and supersonically expanding the vapor as it enters the isolation chambers via the orifices. The vapor condenses in each isolation chamber using the cooling material, and uncondensed vapor is pumped out of the isolation chambers via the pump.

  17. Model assessment of protective barrier designs

    SciTech Connect

    Fayer, M.J.; Conbere, W.; Heller, P.R.; Gee, G.W.

    1985-11-01

    A protective barrier is being considered for use at the Hanford site to enhance the isolation of previously disposed radioactive wastes from infiltrating water, and plant and animal intrusion. This study is part of a research and development effort to design barriers and evaluate their performance in preventing drainage. A fine-textured soil (the Composite) was located on the Hanford site in sufficient quantity for use as the top layer of the protective barrier. A number of simulations were performed by Pacific Northwest Laboratory to analyze different designs of the barrier using the Composite soil as well as the finer-textured Ritzville silt loam and a slightly coarser soil (Coarse). Design variations included two rainfall rates (16.0 and 30.1 cm/y), the presence of plants, gravel mixed into the surface of the topsoil, an impermeable boundary under the topsoil, and moving the waste form from 10 to 20 m from the barrier edge. The final decision to use barriers for enhanced isolation of previously disposed wastes will be subject to decisions resulting from the completion of the Hanford Defense Waste Environmental Impact Statement, which addresses disposal of Hanford defense high-level and transuranic wastes. The one-dimensional simulation results indicate that each of the three soils, when used as the top layer of the protective barrier, can prevent drainage provided plants are present. Gravel amendments to the upper 30 cm of soil (without plants) reduced evaporation and allowed more water to drain.

  18. Assessing barriers to adherence in routine clinical care for pediatric kidney transplant patients.

    PubMed

    Varnell, Charles D; Rich, Kristin L; Nichols, Melissa; Dahale, Devesh; Goebel, Jens W; Pai, Ahna L H; Hooper, David K; Modi, Avani C

    2017-08-01

    Patient-identified barriers to immunosuppressive medications are associated with poor adherence and negative clinical outcomes in transplant patients. Assessment of adherence barriers is not part of routine post-transplant care, and studies regarding implementing such a process in a reliable way are lacking. Using the Model for Improvement and PDSA cycles, we implemented a system to identify adherence barriers, including patient-centered design of a barriers assessment tool, identification of eligible patients, clear roles for clinic staff, and creating a culture of non-judgmental discussion around adherence. We performed time-series analysis of our process measure. Secondary analyses examined the endorsement and concordance of adherence barriers between patient-caregiver dyads. After three methods of testing, the most reliable delivery system was an EHR-integrated tablet that alerted staff of patient eligibility for assessment. Barriers were endorsed by 35% of caregivers (n=85) and 43% of patients (n=60). The most frequently patient-endorsed barriers were forgetting, poor taste, and side effects. Caregivers endorsed forgetting and side effects. Concordance between patient-caregiver dyads was fair (k=0.299). Standardized adherence barriers assessment is feasible in the clinical care of pediatric kidney transplant patients. Features necessary for success included automation, redundant systems with designated staff to identify and mitigate failures, aligned reporting structures, and reliable measurement approaches. Future studies will examine whether barriers predict clinical outcomes (eg, organ rejection, graft loss). © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Engineered Barrier System: Physical and Chemical Environment Model

    SciTech Connect

    D. M. Jolley; R. Jarek; P. Mariner

    2004-02-09

    The conceptual and predictive models documented in this Engineered Barrier System: Physical and Chemical Environment Model report describe the evolution of the physical and chemical conditions within the waste emplacement drifts of the repository. The modeling approaches and model output data will be used in the total system performance assessment (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. These models evaluate the range of potential water compositions within the emplacement drifts, resulting from the interaction of introduced materials and minerals in dust with water seeping into the drifts and with aqueous solutions forming by deliquescence of dust (as influenced by atmospheric conditions), and from thermal-hydrological-chemical (THC) processes in the drift. These models also consider the uncertainty and variability in water chemistry inside the drift and the compositions of introduced materials within the drift. This report develops and documents a set of process- and abstraction-level models that constitute the engineered barrier system: physical and chemical environment model. Where possible, these models use information directly from other process model reports as input, which promotes integration among process models used for total system performance assessment. Specific tasks and activities of modeling the physical and chemical environment are included in the technical work plan ''Technical Work Plan for: In-Drift Geochemistry Modeling'' (BSC 2004 [DIRS 166519]). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system analysis model reports.

  20. The Cementitious Barriers Partnership (CBP) Software Toolbox Capabilities In Assessing The Degradation Of Cementitious Barriers

    SciTech Connect

    Flach, G. P.; Burns, H. H.; Langton, C.; Smith, F. G. III; Brown, K. G.; Kosson, D. S.; Garrabrants, A. C.; Sarkar, S.; van der Sloot, H.; Meeussen, J. C.L.; Samson, E.; Mallick, P.; Suttora, L.; Esh, D. W.; Fuhrmann, M. J.; Philip, J.

    2013-01-11

    The Cementitious Barriers Partnership (CBP) Project is a multi-disciplinary, multi-institutional collaboration supported by the U.S. Department of Energy (US DOE) Office of Tank Waste and Nuclear Materials Management. The CBP program has developed a set of integrated tools (based on state-of-the-art models and leaching test methods) that help improve understanding and predictions of the long-term structural, hydraulic and chemical performance of cementitious barriers used in nuclear applications. Tools selected for and developed under this program have been used to evaluate and predict the behavior of cementitious barriers used in near-surface engineered waste disposal systems for periods of performance up to 100 years and longer for operating facilities and longer than 1000 years for waste disposal. The CBP Software Toolbox has produced tangible benefits to the DOE Performance Assessment (PA) community. A review of prior DOE PAs has provided a list of potential opportunities for improving cementitious barrier performance predictions through the use of the CBP software tools. These opportunities include: 1) impact of atmospheric exposure to concrete and grout before closure, such as accelerated slag and Tc-99 oxidation, 2) prediction of changes in Kd/mobility as a function of time that result from changing pH and redox conditions, 3) concrete degradation from rebar corrosion due to carbonation, 4) early age cracking from drying and/or thermal shrinkage and 5) degradation due to sulfate attack. The CBP has already had opportunity to provide near-term, tangible support to ongoing DOE-EM PAs such as the Savannah River Saltstone Disposal Facility (SDF) by providing a sulfate attack analysis that predicts the extent and damage that sulfate ingress will have on the concrete vaults over extended time (i.e., > 1000 years). This analysis is one of the many technical opportunities in cementitious barrier performance that can be addressed by the DOE-EM sponsored CBP software

  1. Schottky barrier MOSFET systems and fabrication thereof

    DOEpatents

    Welch, J.D.

    1997-09-02

    (MOS) device systems-utilizing Schottky barrier source and drain to channel region junctions are disclosed. Experimentally derived results which demonstrate operation of fabricated N-channel and P-channel Schottky barrier (MOSFET) devices, and of fabricated single devices with operational characteristics similar to (CMOS) and to a non-latching (SRC) are reported. Use of essentially non-rectifying Schottky barriers in (MOS) structures involving highly doped and the like and intrinsic semiconductor to allow non-rectifying interconnection of, and electrical accessing of device regions is also disclosed. Insulator effected low leakage current device geometries and fabrication procedures therefore are taught. Selective electrical interconnection of drain to drain, source to drain, or source to source, of N-channel and/or P-channel Schottky barrier (MOSFET) devices formed on P-type, N-type and Intrinsic semiconductor allows realization of Schottky Barrier (CMOS), (MOSFET) with (MOSFET) load, balanced differential (MOSFET) device systems and inverting and non-inverting single devices with operating characteristics similar to (CMOS), which devices can be utilized in modulation, as well as in voltage controlled switching and effecting a direction of rectification. 89 figs.

  2. Schottky barrier MOSFET systems and fabrication thereof

    DOEpatents

    Welch, James D.

    1997-01-01

    (MOS) device systems-utilizing Schottky barrier source and drain to channel region junctions are disclosed. Experimentally derived results which demonstrate operation of fabricated N-channel and P-channel Schottky barrier (MOSFET) devices, and of fabricated single devices with operational characteristics similar to (CMOS) and to a non-latching (SRC) are reported. Use of essentially non-rectifying Schottky barriers in (MOS) structures involving highly doped and the like and intrinsic semiconductor to allow non-rectifying interconnection of, and electrical accessing of device regions is also disclosed. Insulator effected low leakage current device geometries and fabrication procedures therefore are taught. Selective electrical interconnection of drain to drain, source to drain, or source to source, of N-channel and/or P-channel Schottky barrier (MOSFET) devices formed on P-type, N-type and Intrinsic semiconductor allows realization of Schottky Barrier (CMOS), (MOSFET) with (MOSFET) load, balanced differential (MOSFET) device systems and inverting and non-inverting single devices with operating characteristics similar to (CMOS), which devices can be utilized in modulation, as well as in voltage controled switching and effecting a direction of rectification.

  3. Final Barrier: Small System Compliance

    EPA Science Inventory

    This presentation will discuss the use of point-of-use (POU) technology for small drinking water systems. Information will be provided on the USEPA regulations that allow the use of POU for compliance and the technologies that are listed as SSCT for radium and arsenic. Listing o...

  4. Final Barrier: Small System Compliance

    EPA Science Inventory

    This presentation will discuss the use of point-of-use (POU) technology for small drinking water systems. Information will be provided on the USEPA regulations that allow the use of POU for compliance and the technologies that are listed as SSCT for radium and arsenic. Listing o...

  5. Subsurface barrier validation with the SEAtrace{trademark} system

    SciTech Connect

    Sandra Dalvit Dunn; William Lowry; Veraun Chipman

    1999-09-01

    Under contract to the Department of Energy, Science and Engineering Associates has completed development and testing of a subsurface barrier verification and monitoring system. This system, called SEAtrace{trademark}, is able to locate and size leaks with a high degree of accuracy in subsurface barriers that are emplaced in an unsaturated medium. It uses gaseous tracer injection, in-field real-time monitoring, and real time data analysis to evaluate barrier integrity. The approach is: Conservative as it measures vapor leaks in a containment system whose greatest risk is posed by liquid leaks; Applicable to any impermeable type of barrier emplacement technology in the unsaturated zone; Inexpensive as it uses readily available, non-toxic, nonhazardous gaseous tracers, does not require an inordinately large number of sampling points, and injection and sampling points can be emplaced by direct push techniques; Capable of assessing not only a barrier's initial integrity, but can also provide long-term monitoring. To date, six demonstrations of the system have been completed. Results from two of the demonstrations are detailed in this report. They include the final developmental demonstration of the SEAtrace system and a comparison demonstration of two tracer based verification technologies. The final developmental demonstration of SEAtrace was completed at a naval facility in Brunswick, Maine. The demonstration was funded solely by the DOE and was performed in cooperation with the US Navy, the Environmental Protection Agency, and the Maine Department of Environmental Protection.

  6. Gaps between knowing and doing: understanding and assessing the barriers to optimal health care.

    PubMed

    Cochrane, Lorna J; Olson, Curtis A; Murray, Suzanne; Dupuis, Martin; Tooman, Tricia; Hayes, Sean

    2007-01-01

    A significant gap exists between science and clinical practice guidelines, on the one hand, and actual clinical practice, on the other. An in-depth understanding of the barriers and incentives contributing to the gap can lead to interventions that effect change toward optimal practice and thus to better care. A systematic review of English language studies involving human subjects and published from January 1998 to March 2007 yielded 256 articles that fulfilled established criteria. The analysis was guided by two research questions: How are barriers are assessed? and What types of barriers are identified? The studies abstracted were coded according to 33 emerging themes; placed into seven categories that typified the barriers; grouped as to whether they involved the health care professional, the guideline, the scientific evidence, the patient, or the health system; and organized according to relationship pattern between barriers. The results expand our understanding of how multiple factors pose barriers to optimal clinical practice. The review reveals increasing numbers of behavioral and system barriers. Quantitative survey type assessments continue to dominate barrier research; however, an increasing number of qualitative and mixed-method study designs have emerged recently. The findings establish the evolution of research methodologies and emerging barriers to the translation of knowing to doing. While many studies are methodologically weak, there are indications that designs are becoming more aligned with the complexity of the health care environment. The review provides support for the need to examine multiple factors within the knowledge-to-action process.

  7. Engineered Barrier System performance requirements systems study report. Revision 02

    SciTech Connect

    Balady, M.A.

    1997-01-14

    This study evaluates the current design concept for the Engineered Barrier System (EBS), in concert with the current understanding of the geologic setting to assess whether enhancements to the required performance of the EBS are necessary. The performance assessment calculations are performed by coupling the EBS with the geologic setting based on the models (some of which were updated for this study) and assumptions used for the 1995 Total System Performance Assessment (TSPA). The need for enhancements is determined by comparing the performance assessment results against the EBS related performance requirements. Subsystem quantitative performance requirements related to the EBS include the requirement to allow no more than 1% of the waste packages (WPs) to fail before 1,000 years after permanent closure of the repository, as well as a requirement to control the release rate of radionuclides from the EBS. The EBS performance enhancements considered included additional engineered components as well as evaluating additional performance available from existing design features but for which no performance credit is currently being taken.

  8. 14 CFR 23.691 - Artificial stall barrier system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Artificial stall barrier system. 23.691... Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... pitching motion. (d) Each system must be designed so that the artificial stall barrier can be quickly...

  9. 14 CFR 23.691 - Artificial stall barrier system.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Artificial stall barrier system. 23.691... Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... pitching motion. (d) Each system must be designed so that the artificial stall barrier can be quickly...

  10. 14 CFR 23.691 - Artificial stall barrier system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Artificial stall barrier system. 23.691... Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... pitching motion. (d) Each system must be designed so that the artificial stall barrier can be quickly...

  11. 14 CFR 23.691 - Artificial stall barrier system.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Artificial stall barrier system. 23.691... Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... pitching motion. (d) Each system must be designed so that the artificial stall barrier can be quickly...

  12. 14 CFR 23.691 - Artificial stall barrier system.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Artificial stall barrier system. 23.691... Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... pitching motion. (d) Each system must be designed so that the artificial stall barrier can be quickly...

  13. Overcoming barriers to integrating economic analysis into risk assessment.

    PubMed

    Hoffmann, Sandra

    2011-09-01

    Regulatory risk analysis is designed to provide decisionmakers with a clearer understanding of how policies are likely to affect risk. The systems that produce risk are biological, physical, and social and economic. As a result, risk analysis is an inherently interdisciplinary task. Yet in practice, risk analysis has been interdisciplinary in only limited ways. Risk analysis could provide more accurate assessments of risk if there were better integration of economics and other social sciences into risk assessment itself. This essay examines how discussions about risk analysis policy have influenced the roles of various disciplines in risk analysis. It explores ways in which integrated bio/physical-economic modeling could contribute to more accurate assessments of risk. It reviews examples of the kind of integrated economics-bio/physical modeling that could be used to enhance risk assessment. The essay ends with a discussion of institutional barriers to greater integration of economic modeling into risk assessment and provides suggestions on how these might be overcome.

  14. ENGINEERED BARRIER SYSTEM FEATURES, EVENTS AND PROCESSES

    SciTech Connect

    Jaros, W.

    2005-08-30

    The purpose of this report is to evaluate and document the inclusion or exclusion of engineered barrier system (EBS) features, events, and processes (FEPs) with respect to models and analyses used to support the total system performance assessment for the license application (TSPA-LA). A screening decision, either Included or Excluded, is given for each FEP along with the technical basis for exclusion screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d, e, and f) [DIRS 173273]. The FEPs addressed in this report deal with those features, events, and processes relevant to the EBS focusing mainly on those components and conditions exterior to the waste package and within the rock mass surrounding emplacement drifts. The components of the EBS are the drip shield, waste package, waste form, cladding, emplacement pallet, emplacement drift excavated opening (also referred to as drift opening in this report), and invert. FEPs specific to the waste package, cladding, and drip shield are addressed in separate FEP reports: for example, ''Screening of Features, Events, and Processes in Drip Shield and Waste Package Degradation'' (BSC 2005 [DIRS 174995]), ''Clad Degradation--FEPs Screening Arguments (BSC 2004 [DIRS 170019]), and Waste-Form Features, Events, and Processes'' (BSC 2004 [DIRS 170020]). For included FEPs, this report summarizes the implementation of the FEP in the TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded). This report also documents changes to the EBS FEPs list that have occurred since the previous versions of this report. These changes have resulted due to a reevaluation of the FEPs for TSPA-LA as identified in Section 1.2 of this report and described in more detail in Section 6.1.1. This revision addresses updates in Yucca Mountain Project (YMP) administrative procedures as they

  15. Assessment of communication barriers in community pharmacies.

    PubMed

    Paluck, Elan C; Green, Lawrence W; Frankish, C James; Fielding, David W; Haverkamp, Beth

    2003-12-01

    This study identified previously reported facilitators and barriers to pharmacist-client communication and then evaluated their impact on the observed communication behaviors of pharmacists. Pharmacists (n = 100) completed a seven-page questionnaire collecting information on 11 variables that had been organized according to the Policy, Regulatory and Organizational Constructs in Educational and Ecological Development (PROCEDE) model as predisposing, enabling, or reinforcing of pharmacist communication with their clients. Demographic variables also were included. "Communication quality" served as the study's dependent variable, whereas pharmacist responses served as the independent variables. Communication quality scores for each pharmacist were obtained from the analysis of 765 audiorecordings of verbal exchanges occurring between the study pharmacists and their consenting clients during 4-hour, on-site observation periods. Four of the variables examined in the study were found to share a unique relationship with communication quality (pharmacists' attitude, year of graduation, adherence expectations, and outcome expectations). Hierarchical multiple regression analysis revealed that the variables measured in the questionnaire accounted for 23% of the variance in communication quality scores. Plausible explanations for why the study was unable to capture more of the variance in its proposed relationships and future areas for research are provided.

  16. Failure mechanisms of thermal barrier systems

    NASA Astrophysics Data System (ADS)

    Xu, Tao

    Thermal barrier coatings (TBCs) are widely used in turbines for propulsion and power generation. The benefit results from their ability to sustain high thermal gradients in the presence of adequate backside cooling. Lowering the temperature of the metal substrate prolongs the life of the component: whether from environmental attack, creep rupture, or fatigue. Thermal barrier systems exhibit multiple failure mechanisms, depends on the deposition methods of the TBCs, chemical composition of the bond coats, and their working environments. Some of the most prevalent are studied in this thesis. There are two types of thermal barrier systems based on the chemical composition of the bond coats: Pt-aluminide and NiCoCrAlY bond coats. Ratcheting happens the most in the systems with Pt-aluminide bond coats; while edge delamination is considered a possible failure mechanism for the systems with NiCoCrAlY bond coats. Ratcheting is motivated by displacement instability in the thermally grown oxide (TGO). Interactions between cracks induced in TBCs upon thermal cycling have been calculated. Cracks that converge from neighboring imperfections exhibit a minimum energy release rate prior to coalescence. Equating this minimum to the toughness of the TBC provides a criterion for coalescence and failure. Imposing this criterion allows the change in crack length upon cycling and the number of cycles to failure to be ascertained. This simulation capability is used to explore various influences on durability. Samples with NiCoCrAlY bond coat are studied after subjected to thermal cycling in a burner rig. In each case, a dominant delamination has been identified, that extends primarily along the interface between the TGO and the bond coat. Calculations of the delamination energy release rate, upon comparison with the interface toughness, reveals a critical TGO thickness, (h tgo)c ≈ 3mum, comparable to that found experimentally.

  17. Safety assessment of discharge chute isolation barrier preparation and installation

    SciTech Connect

    Meichle, R.H.

    1994-10-21

    This analysis examines activities associated with the installation of isolation barriers in the K Basins at the Hanford Reservation. This revision adds evaluation of barrier drops on stored fuel and basin floor, identifies fuel which will be moved and addresses criticality issues with sludge. The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparisons of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions was made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classifications.

  18. Health technology assessment in Iran: Barriers and solutions

    PubMed Central

    Mohtasham, Farideh; Yazdizadeh, Bahareh; Zali, Zahra; Majdzadeh, Reza; Nedjat, Sima

    2016-01-01

    Background: Health technology assessment (HTA) is a tool utilized for efficient dissemination of technology. For the purpose of encouraging decision-makers to utilize this tool, at first, we need to identify the obstacles in the processes of preparation, utilization, and implementation of HTAs. This study aims to define these barriers and offer solutions for effective utilization of HTA reports produced in Iran. Methods: This qualitative content analysis determines the various beneficiaries of HTA, and utilizes a semi-structured interview with the participants who are all involved in the HTA. Results: Nine out of ten people invited for the interviews accepted the researchers’ invitation. An analysis of barriers and solutions for improving the utilization of HTA reports was conducted in three levels of policy makers (policy level), specialists in healthcare (professional level), and ordinary people (public level). The barriers in the policy level include unsuitability of reports for their audience, incompatible views toward the definition and necessity of health technology assessment, lack of financial resources for report preparation, and limitations in large-scale policymaking in Ministry of Health. Barriers in the professional level include lack of knowledge on HTA among serviceproviders. Barriers in the public level consist of information asymmetry. Conclusion: There are various barriers toward accurate utilization of HTAs in Iran. Thus, a systematic approach which involves people, brings about culture, improves infrastructures, and boosts supervision on the performance is recommended. PMID:27390691

  19. Engineered Barrier System Degradation, Flow, and Transport Process Model Report

    SciTech Connect

    E.L. Hardin

    2000-07-17

    The Engineered Barrier System Degradation, Flow, and Transport Process Model Report (EBS PMR) is one of nine PMRs supporting the Total System Performance Assessment (TSPA) being developed by the Yucca Mountain Project for the Site Recommendation Report (SRR). The EBS PMR summarizes the development and abstraction of models for processes that govern the evolution of conditions within the emplacement drifts of a potential high-level nuclear waste repository at Yucca Mountain, Nye County, Nevada. Details of these individual models are documented in 23 supporting Analysis/Model Reports (AMRs). Nineteen of these AMRs are for process models, and the remaining 4 describe the abstraction of results for application in TSPA. The process models themselves cluster around four major topics: ''Water Distribution and Removal Model, Physical and Chemical Environment Model, Radionuclide Transport Model, and Multiscale Thermohydrologic Model''. One AMR (Engineered Barrier System-Features, Events, and Processes/Degradation Modes Analysis) summarizes the formal screening analysis used to select the Features, Events, and Processes (FEPs) included in TSPA and those excluded from further consideration. Performance of a potential Yucca Mountain high-level radioactive waste repository depends on both the natural barrier system (NBS) and the engineered barrier system (EBS) and on their interactions. Although the waste packages are generally considered as components of the EBS, the EBS as defined in the EBS PMR includes all engineered components outside the waste packages. The principal function of the EBS is to complement the geologic system in limiting the amount of water contacting nuclear waste. A number of alternatives were considered by the Project for different EBS designs that could provide better performance than the design analyzed for the Viability Assessment. The design concept selected was Enhanced Design Alternative II (EDA II).

  20. Systemic barriers to improving vascular access outcomes.

    PubMed

    Sands, Jeffrey J; Ferrell, Lori M; Perry, Michael A

    2002-04-01

    Vascular access dysfunction is the most frequent cause of hospitalization for end-stage renal disease (ESRD) patients. Our system of vascular access care and industry standards developed for historic reasons have resulted in a haphazard approach to access management. The Dialysis Outcome Quality Initiative has provided a road map for improving vascular access management. However, despite widespread acceptance, these recommendations are not routinely followed. This is largely the result of inertia coupled with systemic barriers to improving access outcomes. These barriers include lack of funded pre-ESRD care and preoperative imaging, lack of reimbursement for access monitoring, unavailable surgical and interventional suites, erosion of the real value of the composite rate, bundling of additional new services without rate adjustment, poor accountability of surgeons and hospitals, and a reimbursement system that rewards procedures and, in particular, graft and catheter placement. Currently, Center for Medicare and Medicaid Services is reevaluating the composite rate and its included bundle of services. To provide the best access care with the fewest complications while insuring multidisciplinary involvement and accountability, a realistic appraisal and realignment of incentives must be developed to insure improvement of access care in the United States.

  1. Safety assessment of discharge chute isolation barrier preparation and installation

    SciTech Connect

    Meichle, R.H.

    1994-09-29

    The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparison of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions were made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classification.

  2. A new physical barrier system for seawater intrusion control

    NASA Astrophysics Data System (ADS)

    Abdoulhalik, Antoifi; Ahmed, Ashraf; Hamill, G. A.

    2017-06-01

    The construction of subsurface physical barriers is one of various methods used to control seawater intrusion (SWI) in coastal aquifers. This study proposes the mixed physical barrier (MPB) as a new barrier system for seawater intrusion control, which combines an impermeable cutoff wall and a semi-permeable subsurface dam. The effect of the traditionally-used physical barriers on transient saltwater wedge dynamics was first explored for various hydraulic gradients, and the workability of the MPB was thereafter thoroughly analysed. A newly developed automated image analysis based on light-concentration conversion was used in the experiments, which were completed in a porous media tank. The numerical code SEAWAT was used to assess the consistency of the experimental data and examine the sensitivity of the performance of the barriers to various key parameters. The results show that the MPB induced a visible lifting of the dense saline flux upward towards the outlet by the light freshwater. This saltwater lifting mechanism, observed for the first time, induced significant reduction to the saline water intrusion length. The use of the MPB yielded up to 62% and 42% more reduction of the saltwater intrusion length than the semi-permeable dam and the cutoff wall, respectively. The performance achieved by the MPB with a wall depth of 40% of the aquifer thickness was greater than that of a single cutoff wall with a penetration depth of 90% of the aquifer thickness (about 13% extra reduction). This means that the MPB could produce better seawater intrusion reduction than the traditionally used barriers at even lower cost.

  3. Article Including Environmental Barrier Coating System

    NASA Technical Reports Server (NTRS)

    Lee, Kang N. (Inventor)

    2015-01-01

    An enhanced environmental barrier coating for a silicon containing substrate. The enhanced barrier coating may include a bond coat doped with at least one of an alkali metal oxide and an alkali earth metal oxide. The enhanced barrier coating may include a composite mullite bond coat including BSAS and another distinct second phase oxide applied over said surface.

  4. Evaluation and Systems Integration of Physical Security Barrier Systems

    DTIC Science & Technology

    1991-05-30

    INVESTIGATED 1 (31)/ RESPONSE/DETERRENT SYSTEMS 2 BONICH, R./ BELVOIR RD&E/ - 3 1473 4 01-01-82 5 - 6 BARRIER RESPONSE SYSTEMS (I.E. FOAM, SOUND, LIGHT, NITINOL ...NONMAGNETIC NITONOL ALLOYS 2 BUCHLER, W. 3 33-216 4 -- /--/-- 5- 6 NITINOL ALLOY ’MEMORY METAL’ (PACKAGE OF PAPERS) 1 (52)/ A PROCEDURE TO INTEGRATE

  5. Development of the Barriers to Error Disclosure Assessment Tool.

    PubMed

    Welsh, Darlene; Zephyr, Dominique; Pfeifle, Andrea L; Carr, Douglas E; Fink, Joseph L; Jones, Mandy

    2017-06-30

    An interprofessional group of health colleges' faculty created and piloted the Barriers to Error Disclosure Assessment tool as an instrument to measure barriers to medical error disclosure among health care providers. A review of the literature guided the creation of items describing influences on the decision to disclose a medical error. Local and national experts in error disclosure used a modified Delphi process to gain consensus on the items included in the pilot. After receiving university institutional review board approval, researchers distributed the tool to a convenience sample of physicians (n = 19), pharmacists (n = 20), and nurses (n = 20) from an academic medical center. Means and SDs were used to describe the sample. Intraclass correlation coefficients were used to examine test-retest correspondence between the continuous items on the scale. Factor analysis with varimax rotation was used to determine factor loadings and examine internal consistency reliability. Cronbach α coefficients were calculated during initial and subsequent administrations to assess test-retest reliability. After omitting 2 items with intraclass correlation coefficient of less than 0.40, intraclass correlation coefficients ranged from 0.43 to 0.70, indicating fair to good test-retest correspondence between the continuous items on the final draft. Factor analysis revealed the following factors during the initial administration: confidence and knowledge barriers, institutional barriers, psychological barriers, and financial concern barriers to medical error disclosure. α Coefficients of 0.85 to 0.93 at time 1 and 0.82 to 0.95 at time 2 supported test-retest reliability. The final version of the 31-item tool can be used to measure perceptions about abilities for disclosing, impressions regarding institutional policies and climate, and specific barriers that inhibit disclosure by health care providers. Preliminary evidence supports the tool's validity and reliability for measuring

  6. Applications of barrier bucket RF systems at Fermilab

    SciTech Connect

    Bhat, C.M.; /Fermilab

    2006-03-01

    In recent years, the barrier rf systems have become important tools in a variety of beam manipulation applications at synchrotrons. Four out of six proton synchrotrons at Fermilab are equipped with broad-band barrier rf systems. All of the beam manipulations pertaining to the longitudinal phase space in the Fermilab Recycler (synchrotron used for antiproton storage) are carried out using a barrier system. Recently, a number of new applications of barrier rf systems have been developed- the longitudinal momentum mining, longitudinal phase-space coating, antiproton stacking, fast bunch compression and more. Some of these techniques have been critical for the recent spectacular success of the collider performance at the Fermilab Tevatron. Barrier bunch coalescing to produce bright proton bunches has a high potential to increase proton antiproton luminosity significantly. In this paper, I will describe some of these techniques in detail. Finally, I make a few general remarks on issues related to barrier systems.

  7. International Collaboration Activities on Engineered Barrier Systems

    SciTech Connect

    Jove-Colon, Carlos F.

    2016-08-31

    The Used Fuel Disposition Campaign (UFDC) within the DOE Fuel Cycle Technologies (FCT) program has been engaging in international collaborations between repository R&D programs for high-level waste (HLW) disposal to leverage on gathered knowledge and laboratory/field data of near- and far-field processes from experiments at underground research laboratories (URL). Heater test experiments at URLs provide a unique opportunity to mimetically study the thermal effects of heat-generating nuclear waste in subsurface repository environments. Various configurations of these experiments have been carried out at various URLs according to the disposal design concepts of the hosting country repository program. The FEBEX (Full-scale Engineered Barrier Experiment in Crystalline Host Rock) project is a large-scale heater test experiment originated by the Spanish radioactive waste management agency (Empresa Nacional de Residuos Radiactivos S.A. – ENRESA) at the Grimsel Test Site (GTS) URL in Switzerland. The project was subsequently managed by CIEMAT. FEBEX-DP is a concerted effort of various international partners working on the evaluation of sensor data and characterization of samples obtained during the course of this field test and subsequent dismantling. The main purpose of these field-scale experiments is to evaluate feasibility for creation of an engineered barrier system (EBS) with a horizontal configuration according to the Spanish concept of deep geological disposal of high-level radioactive waste in crystalline rock. Another key aspect of this project is to improve the knowledge of coupled processes such as thermal-hydro-mechanical (THM) and thermal-hydro-chemical (THC) operating in the near-field environment. The focus of these is on model development and validation of predictions through model implementation in computational tools to simulate coupled THM and THC processes.

  8. Neurotoxicology of the Brain Barrier System: New Implications

    PubMed Central

    Zheng, Wei

    2014-01-01

    The concept of a barrier system in the brain has existed for nearly a century. The barrier that separates the blood from the cerebral interstitial fluid is defined as the blood-brain barrier, while the one that discontinues the circulation between the blood and cerebrospinal fluid is named the blood-cerebrospinal fluid barrier. Evidence in the past decades suggests that brain barriers are subject to toxic insults from neurotoxic chemicals circulating in blood. The aging process and some disease states render barriers more vulnerable to insults arising inside and outside the barriers. The implication of brain barriers in certain neurodegenerative diseases is compelling, although the contribution of chemical-induced barrier dysfunction in the etiology of any of these disorders remains poorly understood. This review examines what is currently understood about brain barrier systems in central nervous system disorders by focusing on chemical-induced neurotoxicities including those associated with nitrobenzenes, N-methyl-D-aspartate, cyclosporin A, pyridostigmine bromide, aluminum, lead, manganese, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and 3-nitropropionic acid. Contemporary research questions arising from this growing understanding show enormous promises for brain researchers, toxicologists, and clinicians. PMID:11778669

  9. Surface Treatment System Using Dielectric Barrier Discharge

    NASA Astrophysics Data System (ADS)

    Daniels, Ryan; Gershman, Sophia; Faust, Jessica

    2012-10-01

    Atmospheric pressure plasmas have been used recently to improve surface properties of materials. For example, plasma treatment improves wettability, activates and functionalizes the surface of polyethylene making it more suitable for biological applications. We have designed and constructed a system that allows the study of the effect of dielectric barrier discharge (DBD) on the surface properties of treated materials. Preliminary results show that 55 second treatment by the DBD in a 1mm gap reduces the contact angle of polyethylene from 78 +/- 1 before to 40 +/- 1 after the treatment. The DBD is generated using a 15kV, 1kHz pulsed dc power supply a mixture of Ar and O2 as the carrier gas. The study parameters include the ratios of O2 to Ar, the power supply frequency and duty cycle. To perform surface analysis, we have designed a transfer chamber. A bellows drive is used to transport the sample to the mobile transfer chamber and then to a test chamber without exposure to the environment. Plasma treatment improves biological compatibility of polyethylene and makes it suitable for use in implants, prosthetics, and cell cultures.

  10. Barriers to household investment in residential energy conservation: preliminary assessment

    SciTech Connect

    Hoffman, W.L.

    1982-12-01

    A general assessment of the range of barriers which impede household investments in weatherization and other energy efficiency improvements for their homes is provided. The relationship of similar factors to households' interest in receiving a free energy audits examined. Rates of return that underly household investments in major conservation improvements are assessed. A special analysis of household knowledge of economically attractive investments is provided that compares high payback improvements specified by the energy audit with the list of needed or desirable conservation improvements identified by respondents. (LEW)

  11. Thermal barrier coating for alloy systems

    DOEpatents

    Seals, Roland D.; White, Rickey L.; Dinwiddie, Ralph B.

    2000-01-01

    An alloy substrate is protected by a thermal barrier coating formed from a layer of metallic bond coat and a top coat formed from generally hollow ceramic particles dispersed in a matrix bonded to the bond coat.

  12. Thermal barrier coating system having improved adhesion

    NASA Technical Reports Server (NTRS)

    Bill, R. C.; Sovey, J. S. (Inventor)

    1982-01-01

    The adherence between a ceramic thermal barrier coating and a metal bond coating is improved by ion sputtering a ceramic film on the bond cost. A ceramic thermal barrier coating is then plasma-sprayed onto this primer film. This improves the integrity and strength of the interface between the plasma-sprayed ceramic layer and metallic bond coat which insures stronger adherence between the metal and the ceramic.

  13. Volumetric analysis of a New England barrier system using ground-penetrating-radar and coring techniques

    USGS Publications Warehouse

    Van Heteren, S.; FitzGerald, D.M.; Barber, D.C.; Kelley, J.T.; Belknap, D.F.

    1996-01-01

    Ground-penetrating-radar (GPR) profiles calibrated with core data allow accurate assessments of coastal barrier volumes. We applied this procedure successfully to the barrier system along Saco Bay, Maine (USA), as part of a sediment-budget study that focused on present-day sand volumes in various coastal, shoreface, and inner-shelf lith-osomes, and on sand fluxes that have affected the volume or distribution of sand in these sediment bodies through time. On GPR profiles, the components of the barrier lithosome are readily differentiated from other facies, except where the radar signal is attenuated by brackish or salty groundwater. Significant differences between dielectric properties of the barrier lithosome and other units commonly result in strong boundary reflectors. The mostly sandy barrier sediments allow deep penetration of GPR waves, in contrast to finer-grained strata and till-covered bedrock. Within the Saco Bay barrier system, 22 ??3 x 106 m3 of sediment are unevenly distributed. Two-thirds of the total barrier volume is contained within the northern and southern ends of the study area, in the Pine Point spit and the Ferry Beach/Goosefare complex, respectively. The central area around Old Orchard Beach is locally covered by only a thin veneer of barrier sand, averaging <3 m, that unconformably overlies shallow pre-Holocene facies. The prominence of barrier-spit facies and the distribution pattern of back-barrier sediments indicate that a high degree of segmentation, governed by antecedent topography, has affected the development of the Saco Bay barrier system. The present-day configuration of the barrier and back-barrier region along Saco Bay, however, conceals much of its early compartmentalized character.

  14. The development of an audit technique to assess the quality of safety barrier management.

    PubMed

    Guldenmund, Frank; Hale, Andrew; Goossens, Louis; Betten, Jeroen; Duijm, Nijs Jan

    2006-03-31

    This paper describes the development of a management model to control barriers devised to prevent major hazard scenarios. Additionally, an audit technique is explained that assesses the quality of such a management system. The final purpose of the audit technique is to quantify those aspects of the management system that have a direct impact on the reliability and effectiveness of the barriers and, hence, the probability of the scenarios involved. First, an outline of the management model is given and its elements are explained. Then, the development of the audit technique is described. Because the audit technique uses actual major hazard scenarios and barriers within these as its focus, the technique achieves a concreteness and clarity that many other techniques often lack. However, this strength is also its limitation, since the full safety management system is not covered with the technique. Finally, some preliminary experiences obtained from several test sites are compiled and discussed.

  15. Barriers to childhood immunization: findings from a needs assessment study.

    PubMed

    Thomas, M; Kohli, Vandana; King, Dixie

    2004-01-01

    This study examines the current status of immunization among 0-3 year old children in Bakersfield and identifies barriers that prevent families from immunizing their children. A survey research design using a stratified sampling method was employed to collect data from 207 randomly selected English and Spanish speaking households having at least one child between the ages of 0-3 in Bakersfield. The findings reveal that 49% of the parents had no shot cards regarding children's immunization status. However, a significant majority of them immunized their children despite having no records. The most commonly reported consumer related barrier for late immunization was having a sick child followed by lack of parental memory and fear of side effects. The major provider-related barriers included lack of an opening for an appointment with the health care provider, limited clinic hours, and long lines in clinics. Lack of transportation was the single most systemic barrier. These findings suggest that reminder calls, increased transportation, weekend clinics and better rapport with parents can improve the immunization rates in ethnically diverse rural communities.

  16. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    SciTech Connect

    Hampikian, J.M.; Carter, W.B.

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  17. The rapid assessment of hospital procurement barriers in donation: assessing hospitals for change.

    PubMed

    Siminoff, Laura A; Marshall, Heather M

    2009-01-01

    Assessment of the hospital environment is integral to improving the organ donation process in healthcare organizations. This paper introduces a novel approach to the assessment and improvement of donation processes: the Rapid Assessment of hospital Procurement barriers in Donation (RAPiD). The RAPiD is a qualitative needs assessment tool for identifying barriers to donor identification and referral, and family requests for donation. Improving the donation process has become a national priority and can potentially save or improve the lives of thousands of Americans each year. The RAPID yields a rich description of the hospital environment that is readily translated into action-oriented recommendations for change.

  18. Pressurized security barrier and alarm system

    DOEpatents

    Carver, D.W.

    1995-04-11

    A security barrier for placement across a passageway is made up of interconnected pressurized tubing made up in a grid pattern with openings too small to allow passage. The tubing is connected to a pressure switch, located away from the barrier site, which activates an alarm upon occurrence of a pressure drop. A reinforcing bar is located inside and along the length of the tubing so as to cause the tubing to rupture and set off the alarm upon an intruder`s making an attempt to crimp and seal off a portion of the tubing by application of a hydraulic tool. Radial and rectangular grid patterns are disclosed. 7 figures.

  19. Pressurized security barrier and alarm system

    DOEpatents

    Carver, Don W.

    1995-01-01

    A security barrier for placement across a passageway is made up of interconnected pressurized tubing made up in a grid pattern with openings too small to allow passage. The tubing is connected to a pressure switch, located away from the barrier site, which activates an alarm upon occurrence of a pressure drop. A reinforcing bar is located inside and along the length of the tubing so as to cause the tubing to rupture and set off the alarm upon an intruder's making an attempt to crimp and seal off a portion of the tubing by application of a hydraulic tool. Radial and rectangular grid patterns are disclosed.

  20. Neuropsychological assessment of refugees: Methodological and cross-cultural barriers.

    PubMed

    Veliu, Bahrie; Leathem, Janet

    2016-07-06

    Cross-cultural research in neuropsychological assessment has primarily focused on Hispanic and African American populations. Less is known about the impact of language, culture, education, socioeconomic factors, and life experiences on assessment for other cultural groups. We highlight the methodological and cross-cultural barriers encountered at each stage of the neuropsychological assessment of Arabic- and Burmese-speaking refugees, who were culturally and linguistically diverse (CALD). A total of 18 refugees (13 men/five women; in their 20-50s) who were victims of torture in their countries of origin, some with post-traumatic stress disorder (PTSD) and now residents in New Zealand, were seen for neuropsychological assessment. Measures were officially translated, back translated, and administered with the assistance of professional interpreters. Multiple challenges arose in terms of administration (e.g., use of interpreters, interactions with the tester, assessment environment, assessment experience, and motivation), scoring, and interpretation (e.g., age appropriate scoring, estimation of prior function, estimation of brain injury severity, obtaining collateral information), the tests themselves, and ecological validity. There are more challenges in the neuropsychological assessment of people who are CALD than can be managed by adhering to current guidelines. The best approach is to find a balance between maintaining assessment integrity and working creatively and sensitively with this group.

  1. Hybrid life cycle assessment comparison of colloidal silica and cement grouted soil barrier remediation technologies.

    PubMed

    Gallagher, Patricia M; Spatari, Sabrina; Cucura, Jeffrey

    2013-04-15

    Site remediation involves balancing numerous costs and benefits but often neglects the environmental impacts over the entire project life cycle. Life cycle assessment (LCA) offers a framework for inclusion of global environmental "systems-level" decision metrics in combination with technological and cost analysis. We compare colloidal silica (CS) and cement grouted soil barrier remediation technologies for soils affected by low level radionuclides at a U.S. Superfund site using hybrid LCA methods. CS is a new, high performance grouting material installed using permeation grouting techniques. Cement, a more traditional grouting material, is typically installed using jet grouting techniques. Life cycle impacts were evaluated using the US EPA TRACI 2 model. Results show the highest life cycle environmental impacts for the CS barrier occur during materials production and transportation to the site. In general, the life cycle impacts for the cement barrier were dominated by materials production; however, in the extreme scenario the life cycle impacts were dominated by truck transportation of spoils to a distant, off-site radioactive waste facility. It is only in the extreme scenario tested in which soils are transported by truck (Option 2) that spoils waste transport dominates LCIA results. Life cycle environmental impacts for both grout barriers were most sensitive to resource input requirements for manufacturing volumes and transportation. Uncertainty associated with the efficacy of new technology such as CS over its required design life indicates that barrier replacement could increase its life cycle environmental impact above that of the cement barrier.

  2. Assessment of skin barrier function and biochemical changes of ex vivo human skin in response to physical and chemical barrier disruption.

    PubMed

    Döge, Nadine; Avetisyan, Araks; Hadam, Sabrina; Pfannes, Eva Katharina Barbosa; Rancan, Fiorenza; Blume-Peytavi, Ulrike; Vogt, Annika

    2017-07-01

    Topical dermatotherapy is intended to be used on diseased skin. Novel drug delivery systems even address differences between intact and diseased skin underlining the need for pre-clinical assessment of different states of barrier disruption. Herein, we studied how short-term incubation in culture media compared to incubation in humidified chambers affects human skin barrier function and viability. On both models we assessed different types and intensities of physical and chemical barrier disruption methods with regard to structural integrity, biophysical parameters and cytokine levels. Tissue degeneration and proliferative activity limited the use of tissue cultures to 48h. Viability is better preserved in cultured tissue. Tape-stripping (50×TS) and 4h sodium lauryl sulfate (SLS) pre-treatment were identified as highly reproducible and effective procedures for barrier disruption. Transepidermal water loss (TEWL) values reproducibly increased with the intensity of disruption while sebum content and skin surface pH were of limited value. Interleukin (IL)-6/8 and various chemokines and proteases were increased in tape-stripped skin which was more pronounced in SLS-treated skin tissue extracts. Thus, albeit limited to 48h, cultured full-thickness skin maintained several barrier characteristics and responded to different intensities of barrier disruption. Potentially, these models can be used to assess pre-clinically the efficacy and penetration of anti-inflammatory compounds. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Thermal barrier coating system with intermetallic overlay bond coat

    SciTech Connect

    Duderstadt, E.C.; Nagaraj, B A.

    1993-08-24

    A superalloy article is described having a thermal barrier coating system thereon, comprising: a substrate made of a material selected from the group consisting of a nickel-based superalloy and a cobalt-based superalloy; and a thermal barrier coating system on the substrate, the thermal barrier coating system including an intermetallic bond coat overlying the substrate, the bond coat being selected from the group consisting of a nickel aluminide and a platinum aluminide intermetallic compound, a thermally grown aluminum oxide layer overlying the intermetallic bond coat, and a ceramic topcoat overlying the aluminum oxide layer.

  4. Mating system as a barrier to gene flow.

    PubMed

    Hu, Xin-Sheng

    2015-05-01

    Understanding mating system as one of reproductive isolating barriers remains important although this barrier is classified in a different sense from behavioral, ecological, and mechanical isolating barriers. Selfing enhances incipient speciation while outcrossing facilitates species integrity. Here, I study how mating system affects gene exchanges between genetically diverging species in a hybrid zone. Results show that a predominant selfing species has a greater barrier to selective gene flow than does a predominant outcrossing species. Barrier to neutral gene flow convexly changes with the selfing rate due to linkage disequilibrium, with a maximum at around intermediate selfing rate. Asymmetric transient or steady-state barriers to neutral gene flow occur between two sides of a hybrid zone when the neutral gene is affected by its linked selective gene whose alternative alleles are adaptive to heterogeneous habitats. Selfing interacts with both a physical barrier and a density-dependent ecological regulation (a logarithmic model) to strengthen the barriers to neutral and selective gene flow. This theory helps to interpret incipient speciation driven by selfing or to explain the asymmetric gene flow or unequal genomic mixtures between closely related species caused by their asymmetric mating systems in natural hybrid zones.

  5. Barriers and facilitators of suicide risk assessment in emergency departments: a qualitative study of provider perspectives.

    PubMed

    Petrik, Megan L; Gutierrez, Peter M; Berlin, Jon S; Saunders, Stephen M

    2015-01-01

    To understand emergency department (ED) providers' perspectives regarding the barriers and facilitators of suicide risk assessment and to use these perspectives to inform recommendations for best practices in ED suicide risk assessment. Ninety-two ED providers from two hospital systems in a Midwestern state responded to open-ended questions via an online survey that assessed their perspectives on the barriers and facilitators to assess suicide risk as well as their preferred assessment methods. Responses were analyzed using an inductive thematic analysis approach. Qualitative analysis yielded six themes that impact suicide risk assessment. Time, privacy, collaboration and consultation with other professionals and integration of a standard screening protocol in routine care exemplified environmental and systemic themes. Patient engagement/participation in assessment and providers' approach to communicating with patients and other providers also impacted the effectiveness of suicide risk assessment efforts. The findings inform feasible suicide risk assessment practices in EDs. Appropriately utilizing a collaborative, multidisciplinary approach to assess suicide-related concerns appears to be a promising approach to ameliorate the burden placed on ED providers and facilitate optimal patient care. Recommendations for clinical care, education, quality improvement and research are offered. Published by Elsevier Inc.

  6. Assessment of Oral Health Needs and Barriers to Care in a Gullah Community – Hollywood Smiles

    PubMed Central

    Leite, Renata; Hudson, Christine; West, Lynn; Carpenter, Elizabeth; Andrews, Jeannette O.

    2014-01-01

    Objectives To assess the oral health (OH) needs and barriers to OH care in Gullah African American communities. Methods A community advisory board was formed to guide the research study. Five focus groups (n=27) were conducted to explore the OH needs/barriers. Participants completed demographic surveys and participated in discussions facilitated by open-ended questions. All sessions were audio-recorded, transcribed and analyzed using NVivo8. Results Facilitators of OH included positive experiences and modeling. Fear and access to care were the most cited barriers. Tooth extraction was the dental treatment of choice. Intervention recommendations included improving clinic access, using the churches to socially influence receipt of OH care, providing group educational sessions with OH specialists, and having local “lay people” to provide support and to help navigate OH care systems. Conclusions The design of a multi-level culturally and locally relevant intervention may lead to a decrease in OH disparities in Gullah communities. PMID:23793251

  7. Assessing materials (''Getters'') to immobilize or retard the transport of technetium through the engineered barrier system at the potential Yucca Mountain nuclear waste repository

    SciTech Connect

    Viani, B E

    1999-03-15

    Current performance assessment calculations show that technetium (Tc) and neptunium (Np) will deliver the major fraction of the radiation dose to the accessible environment from the potential Yucca Mountain nuclear waste repository. Therefore, materials that can immobilize or delay the transport of Tc or Np (getters) are being considered for addition to either the waste-package or the backfill adjacent to the waste-package. Of the two radionuclides, Tc presents the greater challenge in identifying a suitable getter material. This report identifies several materials that warrant further consideration for immobilizing and/or sorbing Tc as additives to the backfill, and recommends active carbon and an inorganic oxide for initial testing. Other materials, such as zero valent iron, might be useful as getters if they were placed in the waste package itself, a subject that merits further investigation.

  8. Combustion chemical vapor deposited coatings for thermal barrier coating systems

    SciTech Connect

    Hampikian, J.M.; Carter, W.B.

    1995-12-31

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings. In this report, the evaluation of alumina and ceria coatings on a nickel-chromium alloy is described.

  9. Functions of an engineered barrier system for a nuclear waste repository in basalt

    SciTech Connect

    Coons, W.E.; Moore, E.L.; Smith, M.J.; Kaser, J.D.

    1980-01-01

    Defined in this document are the functions of components selected for an engineered barrier system for a nuclear waste repository in basalt. The definitions provide a focal point for barrier material research and development by delineating the purpose and operative lifetime of each component of the engineered system. A five-component system (comprised of waste form, canister, buffer, overpack, and tailored backfill) is discussed in terms of effective operation throughout the course of repository history, recognizing that the emplacement environment changes with time. While components of the system are mutually supporting, redundancy is provided by subsystems of physical and chemical barriers which act in concert with the geology to provide a formidable barrier to transport of hazardous materials to the biosphere. The operating philosophy of the conceptual engineered barrier system is clarified by examples pertinent to storage in basalt, and a technical approach to barrier design and material selection is proposed. A method for system validation and qualification is also included which considers performance criteria proposed by external agencies in conjunction with site-specific models and risk assessment to define acceptable levels of system performance.

  10. Reliability assessment on interfacial failure of thermal barrier coatings

    NASA Astrophysics Data System (ADS)

    Guo, Jin-Wei; Yang, Li; Zhou, Yi-Chun; He, Li-Min; Zhu, Wang; Cai, Can-Ying; Lu, Chun-Sheng

    2016-10-01

    Thermal barrier coatings (TBCs) usually exhibit an uncertain lifetime owing to their scattering mechanical properties and severe service conditions. To consider these uncertainties, a reliability assessment method is proposed based on failure probability analysis. First, a limit state equation is established to demarcate the boundary between failure and safe regions, and then the failure probability is calculated by the integration of a probability density function in the failure area according to the first- or second-order moment. It is shown that the parameters related to interfacial failure follow a Weibull distribution in two types of TBC. The interfacial failure of TBCs is significantly affected by the thermal mismatch of material properties and the temperature drop in service.

  11. How to Assess if QM Can Break Down Barriers

    ERIC Educational Resources Information Center

    Kaelin, Roy A.

    2016-01-01

    Requiring savvy, online courses can present a perceived barrier to adult learners for a variety of reasons, but ease of access due to inadequate navigability should not be one of those barriers. Re-tooling online courses to standards of Quality Matters (QM) can lessen that barrier to access, making adult learners more participatory. Internal…

  12. The role of plants on isolation barrier systems

    SciTech Connect

    Link, S.O.; Downs, J.L.; Waugh, W.J.

    1994-11-01

    Surface barriers are used to isolate buried wastes from the environment. Most have been built for short-term isolation. The need to isolate radioactive wastes from the environment requires that the functional integrity of a barrier be maintained for thousands of years. Barrier function strongly depends on vegetation. Plants reduce wind and water erosion and minimize drainage, but may transport contaminants if roots extend into buried wastes. Our review of the function of plants on surface barriers focuses on the role of plants across mesic to arid environments and gives special consideration to studies done at Hanford. The Hanford Barrier Development Program was created to design and test an earthen cover system to inhibit water infiltration, plant and animal intrusion, and wind and water erosion, while isolating buried wastes for at least 1000 years. Studies at the Hanford have shown that plants will significantly interact with the barrier. Plants transpire soil water back into the atmosphere. Deep-rooted perennials best recycle water; soil water may drain through the root zone of shallow-rooted annuals. Lysimeter studies indicate that a surface layer of fine soil with deep-rooted plants precludes drainage even with three times normal precipitation. The presence of vegetation greatly reduces water and wind erosion, but deep-rooted plants pose a threat of biointrusion and contaminant transport. The Hanford barrier includes a buried rock layer and asphalt layer to prevent biointrusion.

  13. Thermal model of attic systems with radiant barriers

    SciTech Connect

    Wilkes, K.E.

    1991-07-01

    This report summarizes the first phase of a project to model the thermal performance of radiant barriers. The objective of this phase of the project was to develop a refined model for the thermal performance of residential house attics, with and without radiant barriers, and to verify the model by comparing its predictions against selected existing experimental thermal performance data. Models for the thermal performance of attics with and without radiant barriers have been developed and implemented on an IBM PC/AT computer. The validity of the models has been tested by comparing their predictions with ceiling heat fluxes measured in a number of laboratory and field experiments on attics with and without radiant barriers. Cumulative heat flows predicted by the models were usually within about 5 to 10 percent of measured values. In future phases of the project, the models for attic/radiant barrier performance will be coupled with a whole-house model and further comparisons with experimental data will be made. Following this, the models will be utilized to provide an initial assessment of the energy savings potential of radiant barriers in various configurations and under various climatic conditions. 38 refs., 14 figs., 22 tabs.

  14. Versatile fire barrier systems for telephone cable

    NASA Astrophysics Data System (ADS)

    Keith, R. H.; Dahms, D. G.; Licht, R. R.

    Fire barriers prevent smoke and fire spread along and between cables, through walls and floors, and protect critical conductors and equipment from heat. New flexible intrumescent materials expand up to 10 times when heated, are versatile and easy to install in sealing fire rated floor and wall penetrations. Telephone cables have large insulator/metal ratios and may have slack or oval jacketing, making older limited expansion materials ineffective. Strict design for specific cables and cable densities is obsoleted; reactive foaming chemicals are not needed for an effective seal. Fire expanding hydrated silicate particles are incorporated in a neoprene matrix yielding environmental protection for tough, flexible board, sheet, tape, caulk, putty, and foam rubber products. Penetration kits from these materials have been underwriter tested. Their UL ratings are compared with rubber blocks, foaming resins, and compressed washer devices. Traditional telecraft skills and tools install and adapt the new material to many cable types. Ease, simplicity, speed, and sureness of installation entry, and reentry/reseal are related to the fire hazard window of cable, fiber, or coax additions.

  15. ENGINEERED BARRIER SYSTEM FEATURES, EVENTS, AND PROCESSES

    SciTech Connect

    na

    2005-05-30

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the volcanic ash exposure scenario, and the development of dose factors for calculating inhalation dose during volcanic eruption. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1 - 1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed descriptions of the model input parameters, their development and the relationship between the parameters and specific features, events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the volcanic ash exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and from the five analyses that develop parameter values for the biosphere model (BSC 2005 [DIRS 172827]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; and BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis'' (Figure 1 - 1). The objective of this analysis was to develop the BDCFs for the

  16. Assessment of moisturizers and barrier function restoration using dynamic methods.

    PubMed

    Rosado, Catarina; Pinto, Pedro; Rodrigues, Luis Monteiro

    2009-02-01

    Dynamic methods, such as the mathematical modelling of the transepidermal water loss curves that result from a plastic occlusion stress test (POST), enable the complete characterization of the dynamic water balance established between the deep and the superficial skin structures. Previous studies have indicated that this methodology was able to detect impaired barrier function and differentiate normal and dry skin. The objective of the present study is to apply the discriminative capacity of the model to the efficacy testing of moisturizing products. A moisturizing cream containing urea was applied for 2 weeks to the lower leg of volunteers with dry skin. After this period, a POST was performed in the treated and control untreated site and a mathematical model was adjusted to the resulting desorption curves. Results indicate that, after treatment of the skin with the cream for 2 weeks, statistically different kinetic parameters are obtained in the treated site, which suggests an improvement in the water dynamic balance and skin barrier. The data generated by this study was compared with that obtained in a similar investigation that was performed a year earlier. Analysis of the dispersion of results indicates that the method has good reproducibility. These findings confirm that the method has enough sensitivity to assess in vivo the effect of moisturizers on human skin, and also that this evaluation can be performed in a shorter period than that required by the regression method. This methodology can also be considered more informative, because the analysis of the different parameters obtained by the model is indicative of the mechanism of action of the product applied to the skin.

  17. Gamma Ray Measurement Information Barriers for the FMTT Demonstration System

    SciTech Connect

    Wolford Jr., J.K.

    2000-08-16

    The gamma ray attribute measurement information barrier discussion directly complements the discussion of gamma ray measurement, presented in the measurements paper by Gosnell and the general discussion of information barriers (IBs) by MacArthur. It focuses on the information barrier features applied specifically to the gamma-ray measurement and attribute analysis system. The FMTT demonstration instrument represents the second application of an IB design paradigm developed in conjunction with the Joint DOE/DoD Information Barriers Working Group (IBWG) as well as representatives from the Russian Federation's delegations to the Trilateral Initiative and meetings on the agreement for transparency at the Mayak Fissile Storage Facility (FMSF). It is also the second evolutionary step in constructing hardware to embody these jointly developed ideas. The first step was the prototype instrument developed for the Trilateral Initiative, the so-called Attribute Verification System with Information Barriers for Plutonium with Classified Characteristics utilizing Neutron Multiplicity Counting and High-Resolution Gamma-ray Spectroscopy (AVNG), that was demonstrated at Los Alamos National Laboratory in June 1999. Several improvements are evident in this second effort, and will be discussed. Improved, though this information barrier may be, it is still a prototype meant only for demonstration purposes. Its evolving specification and design are appropriately a subject for joint discussion and development. Part of that development must include creating components that the respective governments can trust enough to certify.

  18. Microstructural Evolution and interfacial motion in systems with diffusion barriers

    SciTech Connect

    Perry H. Leo

    2009-03-05

    This research program was designed to model and simulate phase transformations in systems containing diffusion barriers. The modeling work included mass flow, phase formation, and microstructural evolution in interdiffusing systems. Simulation work was done by developing Cahn-Hilliard and phase field equations governing both the temporal and spatial evolution of the composition and deformation fields and other important phase variables.

  19. Case Study: Sensitivity Analysis of the Barataria Basin Barrier Shoreline Wetland Value Assessment Model

    DTIC Science & Technology

    2014-07-01

    Barrier Shoreline Wetland Value Assessment Model1 by S. Kyle McKay2 and J. Craig Fischenich3 OVERVIEW: Sensitivity analysis is a technique for...scale restoration projects to reduce marsh loss and maintain these wetlands as healthy functioning ecosystems. The Barataria Basin Barrier Shoreline...Sensitivity Analysis of the Barataria Basin Barrier Shoreline Wetland Value Assessment Model1 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  20. Assessing blood-brain barrier function using in vitro assays.

    PubMed

    Bressler, Joseph; Clark, Katherine; O'Driscoll, Cliona

    2013-01-01

    The impermeability of the blood-brain barrier (BBB) is due to a number of properties including tight junctions on adjoining endothelial cells, absence of pinocytic vesicles, and expression of multidrug transporters. Although the permeability of many chemicals can be predicted by their polarity, or oil/water partition coefficient, many lipophilic chemicals are not permeable because of multidrug transporters at the luminal and abluminal membranes. In contrast, many nutrients, which are usually polar, cross the BBB more readily than predicted by their oil/water partition coefficients due to the expression of specific nutrient transporters. In vitro models are being developed because rodent models are of low input and relatively expensive. Isolated brain microvessels and cell culture models each offers certain advantages and disadvantages. Isolated brain microvessels are useful in measuring multidrug drug transporters and tight junction integrity, whereas cell culture models allow the investigator to measure directional transport and can be genetically manipulated. In this chapter, we describe how to isolate large batches of brain microvessels from freshly slaughtered cows. The different steps in the isolation procedure include density gradient centrifugations and filtering. Purity is determined microscopically and by marker enzymes. Permeability is assessed by measuring the uptake of fluorescein-labeled dextran in an assay that has been optimized to have a large dynamic range and low inter-day variability. We also describe how to evaluate transendothelial cell electrical resistance and paracellular transport in cell culture models.

  1. Low temperature monitoring system for subsurface barriers

    SciTech Connect

    Vinegar, Harold J.; McKinzie, II. Billy John

    2009-08-18

    A system for monitoring temperature of a subsurface low temperature zone is described. The system includes a plurality of freeze wells configured to form the low temperature zone, one or more lasers, and a fiber optic cable coupled to at least one laser. A portion of the fiber optic cable is positioned in at least one freeze well. At least one laser is configured to transmit light pulses into a first end of the fiber optic cable. An analyzer is coupled to the fiber optic cable. The analyzer is configured to receive return signals from the light pulses.

  2. Feasibility Assessment of Thermal Barrier Seals for Extreme Transient Temperatures

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

    1998-01-01

    The assembly joints of modem solid rocket motor cases are generally sealed using conventional O-ring type seals. The 5500+ F combustion gases produced by rocket motors are kept a safe distance away from the seals by thick layers of phenolic insulation. Special compounds are used to fill insulation gaps leading up to the seals to prevent a direct flowpath to them. Design criteria require that the seals should not experience torching or charring during operation, or their sealing ability would be compromised. On limited occasions, NASA has observed charring of the primary O-rings of the Space Shuttle solid rocket nozzle assembly joints due to parasitic leakage paths opening up in the gap-fill compounds during rocket operation. NASA is investigating different approaches for preventing torching or charring of the primary O-rings. One approach is to implement a braided rope seal upstream of the primary O-ring to serve as a thermal barrier that prevents the hot gases from impinging on the O-ring seals. This paper presents flow, resiliency, and thermal resistance for several types of NASA rope seals braided out of carbon fibers. Burn tests were performed to determine the time to burn through each of the seals when exposed to the flame of an oxyacetylene torch (5500 F), representative of the 5500 F solid rocket motor combustion temperatures. Rope seals braided out of carbon fibers endured the flame for over six minutes, three times longer than solid rocket motor burn time. Room and high temperature flow tests are presented for the carbon seals for different amounts of linear compression. Room temperature compression tests were performed to assess seal resiliency and unit preloads as a function of compression. The thermal barrier seal was tested in a subscale "char" motor test in which the seal sealed an intentional defect in the gap insulation. Temperature measurements indicated that the seal blocked 2500 F combustion gases on the upstream side with very little temperature

  3. Field testing of asphalt-emulsion radon-barrier system

    SciTech Connect

    Hartley, J.N.; Freeman, H.D.; Baker, E.G.; Elmore, M.R.; Nelson, D.A.; Voss, C.F.; Koehmstedt, P.L.

    1981-09-01

    Three years of laboratory and field testing have demonstrated that asphalt emulsion seals are effective radon diffusion barriers. Both laboratory and field tests in 1979, 1980 and 1981 have shown that an asphalt emulsion seal can reduce radon fluxes by greater than 99.9%. The effective diffusion coefficient for the various asphalt emulsion admix seals averages about 10/sup -6/ cm/sup 2//s. The 1981 joint field test is a culmination of all the technology developed to date for asphalt emulsion radon barrier systems. Preliminary results of this field test and the results of the 1980 field test are presented. 18 figures, 6 tables.

  4. Opinion: Assessing the Barriers to Image Guided Drug Delivery

    PubMed Central

    Lanza, Gregory M.; Moonen, Chrit; Baker, James R.; Chang, Esther; Cheng, Zheng; Grodzinski, Piotr; Ferrara, Katherine; Hynynen, Kullervo; Kelloff, Gary; Koo Lee, Yong-Eun; Patri, Anil K; Sept, David; Schnitzer, Jan E.; Wood, Bradford J.; Zhang, Miqin; Zheng, Gang; Farahani, Keyvan

    2014-01-01

    Imaging has become a cornerstone for medical diagnosis and the guidance of patient management. A new field called Image Guided Drug Delivery (IGDD) now combines the vast potential of the radiological sciences with the delivery of treatment and promises to fulfill the vision of personalized medicine. Whether imaging is used to deliver focused energy to drug-laden particles for enhanced, local drug release around tumors, or it is invoked in the context of nanoparticle-based agents to quantify distinctive biomarkers that could risk-stratify patients for improved targeted drug delivery efficiency, the overarching goal of IGDD is to use imaging to maximize effective therapy in diseased tissues and to minimize systemic drug exposure in order to reduce toxicities. Over the last several years innumerable reports and reviews covering the gamut of IGDD technologies have been published, but inadequate attention has been directed towards identifying and addressing the barriers limiting clinical translation. In this consensus opinion, the opportunities and challenges impacting the clinical realization of IGDD-based personalized medicine were discussed as a panel and recommendations were proffered to accelerate the field forward. PMID:24339356

  5. Feasibility Assessment of Thermal Barriers for RSRM Nozzle Joint Locations

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

    1999-01-01

    Solid rockets, including the Space Shuttle solid rocket motor, are generally manufactured in large segments which are then shipped to their final destination where they are assembled. These large segments are sealed with a system of primary and secondary 0-rings to contain combustion gases inside the rocket which are at pressures of up to 900 psi and temperatures of up to 5500 F. The seals are protected from hot combustion gases by thick layers of phenolic insulation and by joint-filling compounds between these layers. Recently, though, routine inspections of nozzle-to-case joints in the Shuttle solid rocket motors during disassembly revealed erosion of the primary O-rings. Jets of hot gas leaked through gaps in the joint-filling compound between the layers of insulation and impinged on the O-rings. This is not supposed to take place, so NASA and Thiokol, the manufacturer of the rockets, initiated an investigation and found that design improvements could be made in this joint. One such improvement would involve using NASA Lewis braided thermal barriers as another level of protection for the O-ring seals against the hot combustion gases.

  6. Ruthenium-containing bond coats for thermal barrier coating systems

    NASA Astrophysics Data System (ADS)

    Tryon, B.; Cao, F.; Murphy, K. S.; Levi, C. G.; Pollock, T. M.

    2006-01-01

    Bond coats for zirconia-based thermal barrier coating systems applied to nickel-based superalloys are typically composed of the B2 NiAl phase. Since RuAl has the same B2 crystal structure but a melting point 400°C higher than NiAl, ruthenium-modified aluminide bond coats could provide improved system temperature capability. Creep experiments on ternary Al-Ni-Ru alloys demonstrate greatly improved creep properties with increasing ruthenium content. Processing paths for ruthenium-modified NiAl-based bond coatings have been established within the bounds of commercially available coating systems. The oxidation resistance of ruthenium-modified bond coats during thermal cycling has been examined, and potential thermal barrier coating system implications are discussed.

  7. Distributed road assessment system

    DOEpatents

    Beer, N. Reginald; Paglieroni, David W

    2014-03-25

    A system that detects damage on or below the surface of a paved structure or pavement is provided. A distributed road assessment system includes road assessment pods and a road assessment server. Each road assessment pod includes a ground-penetrating radar antenna array and a detection system that detects road damage from the return signals as the vehicle on which the pod is mounted travels down a road. Each road assessment pod transmits to the road assessment server occurrence information describing each occurrence of road damage that is newly detected on a current scan of a road. The road assessment server maintains a road damage database of occurrence information describing the previously detected occurrences of road damage. After the road assessment server receives occurrence information for newly detected occurrences of road damage for a portion of a road, the road assessment server determines which newly detected occurrences correspond to which previously detected occurrences of road damage.

  8. Assessment of the water quality and ecosystem health of the Great Barrier Reef (Australia): conceptual models.

    PubMed

    Haynes, David; Brodie, Jon; Waterhouse, Jane; Bainbridge, Zoe; Bass, Deb; Hart, Barry

    2007-12-01

    Run-off containing increased concentrations of sediment, nutrients, and pesticides from land-based anthropogenic activities is a significant influence on water quality and the ecologic conditions of nearshore areas of the Great Barrier Reef World Heritage Area, Australia. The potential and actual impacts of increased pollutant concentrations range from bioaccumulation of contaminants and decreased photosynthetic capacity to major shifts in community structure and health of mangrove, coral reef, and seagrass ecosystems. A detailed conceptual model underpins and illustrates the links between the main anthropogenic pressures or threats (dry-land cattle grazing and intensive sugar cane cropping) and the production of key contaminants or stressors of Great Barrier Reef water quality. The conceptual model also includes longer-term threats to Great Barrier Reef water quality and ecosystem health, such as global climate change, that will potentially confound direct model interrelationships. The model recognises that system-specific attributes, such as monsoonal wind direction, rainfall intensity, and flood plume residence times, will act as system filters to modify the effects of any water-quality system stressor. The model also summarises key ecosystem responses in ecosystem health that can be monitored through indicators at catchment, riverine, and marine scales. Selected indicators include riverine and marine water quality, inshore coral reef and seagrass status, and biota pollutant burdens. These indicators have been adopted as components of a long-term monitoring program to enable assessment of the effectiveness of change in catchment-management practices in improving Great Barrier Reef (and adjacent catchment) water quality under the Queensland and Australian Governments' Reef Water Quality Protection Plan.

  9. Assessment of the Water Quality and Ecosystem Health of the Great Barrier Reef (Australia): Conceptual Models

    NASA Astrophysics Data System (ADS)

    Haynes, David; Brodie, Jon; Waterhouse, Jane; Bainbridge, Zoe; Bass, Deb; Hart, Barry

    2007-12-01

    Run-off containing increased concentrations of sediment, nutrients, and pesticides from land-based anthropogenic activities is a significant influence on water quality and the ecologic conditions of nearshore areas of the Great Barrier Reef World Heritage Area, Australia. The potential and actual impacts of increased pollutant concentrations range from bioaccumulation of contaminants and decreased photosynthetic capacity to major shifts in community structure and health of mangrove, coral reef, and seagrass ecosystems. A detailed conceptual model underpins and illustrates the links between the main anthropogenic pressures or threats (dry-land cattle grazing and intensive sugar cane cropping) and the production of key contaminants or stressors of Great Barrier Reef water quality. The conceptual model also includes longer-term threats to Great Barrier Reef water quality and ecosystem health, such as global climate change, that will potentially confound direct model interrelationships. The model recognises that system-specific attributes, such as monsoonal wind direction, rainfall intensity, and flood plume residence times, will act as system filters to modify the effects of any water-quality system stressor. The model also summarises key ecosystem responses in ecosystem health that can be monitored through indicators at catchment, riverine, and marine scales. Selected indicators include riverine and marine water quality, inshore coral reef and seagrass status, and biota pollutant burdens. These indicators have been adopted as components of a long-term monitoring program to enable assessment of the effectiveness of change in catchment-management practices in improving Great Barrier Reef (and adjacent catchment) water quality under the Queensland and Australian Governments’ Reef Water Quality Protection Plan.

  10. Disposal systems evaluations and tool development : Engineered Barrier System (EBS) evaluation.

    SciTech Connect

    Rutqvist, Jonny; Liu, Hui-Hai; Steefel, Carl I.; Serrano de Caro, M. A.; Caporuscio, Florie Andre; Birkholzer, Jens T.; Blink, James A.; Sutton, Mark A.; Xu, Hongwu; Buscheck, Thomas A.; Levy, Schon S.; Tsang, Chin-Fu; Sonnenthal, Eric; Halsey, William G.; Jove-Colon, Carlos F.; Wolery, Thomas J.

    2011-01-01

    Key components of the nuclear fuel cycle are short-term storage and long-term disposal of nuclear waste. The latter encompasses the immobilization of used nuclear fuel (UNF) and radioactive waste streams generated by various phases of the nuclear fuel cycle, and the safe and permanent disposition of these waste forms in geological repository environments. The engineered barrier system (EBS) plays a very important role in the long-term isolation of nuclear waste in geological repository environments. EBS concepts and their interactions with the natural barrier are inherently important to the long-term performance assessment of the safety case where nuclear waste disposition needs to be evaluated for time periods of up to one million years. Making the safety case needed in the decision-making process for the recommendation and the eventual embracement of a disposal system concept requires a multi-faceted integration of knowledge and evidence-gathering to demonstrate the required confidence level in a deep geological disposal site and to evaluate long-term repository performance. The focus of this report is the following: (1) Evaluation of EBS in long-term disposal systems in deep geologic environments with emphasis on the multi-barrier concept; (2) Evaluation of key parameters in the characterization of EBS performance; (3) Identification of key knowledge gaps and uncertainties; and (4) Evaluation of tools and modeling approaches for EBS processes and performance. The above topics will be evaluated through the analysis of the following: (1) Overview of EBS concepts for various NW disposal systems; (2) Natural and man-made analogs, room chemistry, hydrochemistry of deep subsurface environments, and EBS material stability in near-field environments; (3) Reactive Transport and Coupled Thermal-Hydrological-Mechanical-Chemical (THMC) processes in EBS; and (4) Thermal analysis toolkit, metallic barrier degradation mode survey, and development of a Disposal Systems

  11. Assessing theoretical uncertainties in fission barriers of superheavy nuclei

    DOE PAGES

    Agbemava, S. E.; Afanasjev, A. V.; Ray, D.; ...

    2017-05-26

    Here, theoretical uncertainties in the predictions of inner fission barrier heights in superheavy elements have been investigated in a systematic way for a set of state-of-the-art covariant energy density functionals which represent major classes of the functionals used in covariant density functional theory. They differ in basic model assumptions and fitting protocols. Both systematic and statistical uncertainties have been quantified where the former turn out to be larger. Systematic uncertainties are substantial in superheavy elements and their behavior as a function of proton and neutron numbers contains a large random component. The benchmarking of the functionals to the experimental datamore » on fission barriers in the actinides allows to reduce the systematic theoretical uncertainties for the inner fission barriers of unknown superheavy elements. However, even then they on average increase on moving away from the region where benchmarking has been performed. In addition, a comparison with the results of non-relativistic approaches is performed in order to define full systematic theoretical uncertainties over the state-of-the-art models. Even for the models benchmarked in the actinides, the difference in the inner fission barrier height of some superheavy elements reaches $5-6$ MeV. This uncertainty in the fission barrier heights will translate into huge (many tens of the orders of magnitude) uncertainties in the spontaneous fission half-lives.« less

  12. Assessing theoretical uncertainties in fission barriers of superheavy nuclei

    NASA Astrophysics Data System (ADS)

    Agbemava, S. E.; Afanasjev, A. V.; Ray, D.; Ring, P.

    2017-05-01

    Theoretical uncertainties in the predictions of inner fission barrier heights in superheavy elements have been investigated in a systematic way for a set of state-of-the-art covariant energy density functionals which represent major classes of the functionals used in covariant density functional theory. They differ in basic model assumptions and fitting protocols. Both systematic and statistical uncertainties have been quantified where the former turn out to be larger. Systematic uncertainties are substantial in superheavy elements and their behavior as a function of proton and neutron numbers contains a large random component. The benchmarking of the functionals to the experimental data on fission barriers in the actinides allows reduction of the systematic theoretical uncertainties for the inner fission barriers of unknown superheavy elements. However, even then, on average they increase on moving away from the region where benchmarking has been performed. In addition, a comparison with the results of nonrelativistic approaches is performed in order to define full systematic theoretical uncertainties over the state-of-the-art models. Even for the models benchmarked in the actinides, the difference in the inner fission barrier height of some superheavy elements reaches 5 -6 MeV. This uncertainty in the fission barrier heights will translate into huge (many tens of the orders of magnitude) uncertainties in the spontaneous fission half-lives.

  13. Analysis of developed transition road safety barrier systems.

    PubMed

    Soltani, Mehrtash; Moghaddam, Taher Baghaee; Karim, Mohamed Rehan; Sulong, N H Ramli

    2013-10-01

    Road safety barriers protect vehicles from roadside hazards by redirecting errant vehicles in a safe manner as well as providing high levels of safety during and after impact. This paper focused on transition safety barrier systems which were located at the point of attachment between a bridge and roadside barriers. The aim of this study was to provide an overview of the behavior of transition systems located at upstream bridge rail with different designs and performance levels. Design factors such as occupant risk and vehicle trajectory for different systems were collected and compared. To achieve this aim a comprehensive database was developed using previous studies. The comparison showed that Test 3-21, which is conducted by impacting a pickup truck with speed of 100 km/h and angle of 25° to transition system, was the most severe test. Occupant impact velocity and ridedown acceleration for heavy vehicles were lower than the amounts for passenger cars and pickup trucks, and in most cases higher occupant lateral impact ridedown acceleration was observed on vehicles subjected to higher levels of damage. The best transition system was selected to give optimum performance which reduced occupant risk factors using the similar crashes in accordance with Test 3-21.

  14. Identifying the barriers and enablers to palliative care nurses' recognition and assessment of delirium symptoms: a qualitative study.

    PubMed

    Hosie, Annmarie; Lobb, Elizabeth; Agar, Meera; Davidson, Patricia M; Phillips, Jane

    2014-11-01

    Delirium is underrecognized by nurses, including those working in palliative care settings where the syndrome occurs frequently. Identifying contextual factors that support and/or hinder palliative care nurses' delirium recognition and assessment capabilities is crucial, to inform development of clinical practice and systems aimed at improving patients' delirium outcomes. The aim of the study was to identify nurses' perceptions of the barriers and enablers to recognizing and assessing delirium symptoms in palliative care inpatient settings. A series of semistructured interviews, guided by critical incident technique, were conducted with nurses working in Australian palliative care inpatient settings. A hypoactive delirium vignette prompted participants' recall of delirium and identification of the perceived factors (barriers and enablers) that impacted on their delirium recognition and assessment capabilities. Thematic content analysis was used to analyze the qualitative data. Thirty participants from nine palliative care services provided insights into the barriers and enablers of delirium recognition and assessment in the inpatient setting that were categorized as patient and family, health professional, and system level factors. Analysis revealed five themes, each reflecting both identified barriers and current and/or potential enablers: 1) value in listening to patients and engaging families, 2) assessment is integrated with care delivery, 3) respecting and integrating nurses' observations, 4) addressing nurses' delirium knowledge needs, and 5) integrating delirium recognition and assessment processes. Supporting the development of palliative care nursing delirium recognition and assessment practice requires attending to a range of barriers and enablers at the patient and family, health professional, and system levels. Copyright © 2014 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  15. Test Plan to Assess Fire Effects on the Function of an Engineered Surface Barrier

    SciTech Connect

    Ward, Anderson L.; Berlin, Gregory T.; Cammann, Jerry W.; Leary, Kevin D.; Link, Steven O.

    2008-09-29

    Wildfire is a frequent perturbation in shrub steppe ecosystems, altering the flora, fauna, atmosphere, and soil of these systems. Research on the fire effects has focused mostly on natural ecosystems with essentially no attention on engineered systems like surface barriers. The scope of the project is to use a simulated wildfire to induce changes in an engineered surface barrier and document the effects on barrier performance. The main objective is to quantify the effects of burning and the resulting post-fire conditions on alterations in soil physical properties; hydrologic response, particularly the water balance; geochemical properties; and biological properties. A secondary objective is to use the lessons learned to maximize fire protection in the design of long-term monitoring systems based on electronic sensors. A simulated wildfire will be initiated, controlled and monitored at the 200-BP-1 barrier in collaboration with the Hanford Fire Department during the fall of 2008. The north half of the barrier will be divided into nine 12 x 12 m plots, each of which will be randomly assigned a fuel load of 2 kg m-2 or 4 kg m-2. Each plot will be ignited around the perimeter and flames allowed to carry to the centre. Any remaining unburned vegetation will be manually burned off using a drip torch. Progress of the fire and its effects will be monitored using point measurements of thermal, hydrologic, and biotic variables. Three measures of fire intensity will be used to characterize fire behavior: (1) flame height, (2) the maximum temperature at three vertical profile levels, and (3) total duration of elevated temperature at these levels. Pre-burn plant information, including species diversity, plant height, and canopy diameter will be measured on shrubs from the plots to be burned and from control plots at the McGee ranch. General assessments of shrub survival, recovery, and recruitment will be made after the fire. Near-surface soil samples will be collected pre- and

  16. Emergent Behavior of Coupled Barrier Island - Resort Systems

    NASA Astrophysics Data System (ADS)

    McNamara, D. E.; Werner, B. T.

    2004-12-01

    Barrier islands are attractive sites for resorts. Natural barrier islands experience beach erosion and island overwash during storms, beach accretion and dune building during inter-storm periods, and migration up the continental shelf as sea level rises. Beach replenishment, artificial dune building, seawalls, jetties and groins have been somewhat effective in protecting resorts against erosion and overwash during storms, but it is unknown how the coupled system will respond to long-term sea level rise. We investigate coupled barrier island - resort systems using an agent-based model with three components: natural barrier islands divided into a series of alongshore cells; resorts controlled by markets for tourism and hotel purchases; and coupling via storm damage to resorts and resort protection by government agents. Modeled barrier islands change by beach erosion, island overwash and inlet cutting during storms, and beach accretion, tidal delta growth and dune and vegetation growth between storms. In the resort hotel market, developer agents build hotels and hotel owning agents purchase them using predictions of future revenue and property appreciation, with the goal of maximizing discounted utility. In the tourism market, hotel owning agents set room rental prices to maximize profit and tourist agents choose vacation destinations maximizing a utility based on beach width, price and word-of-mouth. Government agents build seawalls, groins and jetties, and widen the beach and build up dunes by adding sand to protect resorts from storms, enhance beach quality, and maximize resort revenue. Results indicate that barrier islands and resorts evolve in a coupled manner to resort size saturation, with resorts protected against small-to-intermediate-scale storms under fairly stable sea level. Under extended, rapidly rising sea level, protection measures enhance the effect of large storms, leading to emergent behavior in the form of limit cycles or barrier submergence

  17. TEER measurement techniques for in vitro barrier model systems.

    PubMed

    Srinivasan, Balaji; Kolli, Aditya Reddy; Esch, Mandy Brigitte; Abaci, Hasan Erbil; Shuler, Michael L; Hickman, James J

    2015-04-01

    Transepithelial/transendothelial electrical resistance (TEER) is a widely accepted quantitative technique to measure the integrity of tight junction dynamics in cell culture models of endothelial and epithelial monolayers. TEER values are strong indicators of the integrity of the cellular barriers before they are evaluated for transport of drugs or chemicals. TEER measurements can be performed in real time without cell damage and generally are based on measuring ohmic resistance or measuring impedance across a wide spectrum of frequencies. The measurements for various cell types have been reported with commercially available measurement systems and also with custom-built microfluidic implementations. Some of the barrier models that have been widely characterized using TEER include the blood-brain barrier (BBB), gastrointestinal (GI) tract, and pulmonary models. Variations in these values can arise due to factors such as temperature, medium formulation, and passage number of cells. The aim of this article is to review the different TEER measurement techniques and analyze their strengths and weaknesses, determine the significance of TEER in drug toxicity studies, examine the various in vitro models and microfluidic organs-on-chips implementations using TEER measurements in some widely studied barrier models (BBB, GI tract, and pulmonary), and discuss the various factors that can affect TEER measurements. © 2015 Society for Laboratory Automation and Screening.

  18. TEER measurement techniques for in vitro barrier model systems

    PubMed Central

    Srinivasan, Balaji; Kolli, Aditya Reddy; Esch, Mandy Brigitte; Abaci, Hasan Erbil; Shuler, Michael L.; Hickman, James J.

    2015-01-01

    Transepithelial/transendothelial electrical resistance (TEER) is a widely accepted quantitative technique to measure the integrity of tight junction dynamics in cell culture models of endothelial and epithelial monolayers. TEER values are strong indicators of the integrity of the cellular barriers before they are evaluated for transport of drugs or chemicals. TEER measurements can be performed in real-time without cell damage and generally are based on measuring ohmic resistance or measuring impedance across a wide spectrum of frequencies. TEER measurements for various cell types have been reported with commercially available measurement systems and also with custom built microfluidic implementations. Some of the barrier models that have been widely characterized utilizing TEER include the blood-brain barrier (BBB), gastrointestinal (GI) tract, and pulmonary models. Variations in TEER value can arise due to factors such as temperature, medium formulation and passage number of cells. The aim of this paper is to review the different TEER measurement techniques and analyze their strengths and weaknesses, the significance of TEER in drug toxicity studies, examine the various in vitro models and microfluidic organs-on-chips implementations utilizing TEER measurements in some widely studied barrier models (BBB, GI tract and pulmonary), and discuss the various factors that can affect TEER measurements. PMID:25586998

  19. Assessment of Barriers to Changing Practice as CME Outcomes

    ERIC Educational Resources Information Center

    Price, David W.; Miller, Elaine K.; Rahm, Alanna Kulchak; Brace, Nancy E.; Larson, R. Sam

    2010-01-01

    Introduction: Continuing medical education (CME) is meant to drive and support improvements in practice. To achieve this goal, CME activities must move beyond simply purveying knowledge, instead helping attendees to contextualize information and to develop strategies for implementing new learning. CME attendees face different barriers to…

  20. Assessment of Barriers to Changing Practice as CME Outcomes

    ERIC Educational Resources Information Center

    Price, David W.; Miller, Elaine K.; Rahm, Alanna Kulchak; Brace, Nancy E.; Larson, R. Sam

    2010-01-01

    Introduction: Continuing medical education (CME) is meant to drive and support improvements in practice. To achieve this goal, CME activities must move beyond simply purveying knowledge, instead helping attendees to contextualize information and to develop strategies for implementing new learning. CME attendees face different barriers to…

  1. Barriers to success: How baculoviruses establish efficient systemic infections

    PubMed Central

    Passarelli, A. Lorena

    2011-01-01

    The mechanisms used by baculoviruses to exit the midgut and cause systemic infection of their insect hosts have been debated for decades. After being ingested, baculoviruses reach the midgut, where several host barriers need to be overcome in order to establish successful infection. One of these barriers is the basal lamina, a presumably virus-impermeable extracellular layer secreted by the epithelial cells lining the midgut and trachea. This review discusses new evidence that demonstrates how these viruses breach the basal lamina and establish efficient systemic infections. The biochemical mechanisms involved in dismantling basal lamina during baculovirus infection may also provide new insights into the process of basal lamina remodeling in invertebrate and vertebrate animals. PMID:21300392

  2. Implementing District Energy Systems: Municipal Approaches To Overcoming Barriers

    NASA Astrophysics Data System (ADS)

    Simpson, Kevin George

    Climate change and energy security are issues facing municipalities throughout the world. Efficient, resilient, sustainable, community-based energy systems, such as district energy systems (DES), fuelled mostly by renewables, are an important tool for addressing both climate change and energy security at the municipal level. In spite of their benefits, DES are not widely adopted in Canada (CDEA, 2011). This is due to the complex nature of the barriers which project proponents face. This thesis examines the experience of the City of Prince George in adopting and implementing the Downtown DES. Using a case study methodology, data was collected through a review of relevant municipal documents and a series of semi-structured, open-ended interviews. A thematic analysis revealed unexpected barriers related to lack of adequate public consultation and negative perceptions regarding biomass as a fuel for the DES. These `lessons learned' were then developed into recommendations for other municipalities considering DES.

  3. A preliminary experimental study on virtual sound barrier system

    NASA Astrophysics Data System (ADS)

    Zou, Haishan; Qiu, Xiaojun; Lu, Jing; Niu, Feng

    2007-10-01

    Virtual sound barrier (VSB) is an array of loudspeakers and microphones forming an acoustic barrier, which creates a quiet zone without blocking air and light. A 16-channel cylindrical VSB system has been developed and its feasibility is verified by both numerical simulations and experiments. Experimental results in a normal room show that it can create a quiet zone larger than the size of a human head in the low-middle frequency, with a total sound pressure level reduction of more than 10 dB in the quiet zone. The control performance of the system with respect to the frequency, the distribution of the error sensors and the control sources are discussed.

  4. Computational Design and Experimental Validation of New Thermal Barrier Systems

    SciTech Connect

    Guo, Shengmin; Yang, Shizhong; Khosravi, Ebrahim

    2014-04-01

    This project (10/01/2010-9/30/2014), “Computational Design and Experimental Validation of New Thermal Barrier Systems”, originates from Louisiana State University (LSU) Mechanical Engineering Department and Southern University (SU) Department of Computer Science. This project will directly support the technical goals specified in DE-FOA-0000248, Topic Area 3: Turbine Materials, by addressing key technologies needed to enable the development of advanced turbines and turbine-based systems that will operate safely and efficiently using coal-derived synthesis gases. In this project, the focus is to develop and implement novel molecular dynamics method to improve the efficiency of simulation on novel TBC materials; perform high performance computing (HPC) on complex TBC structures to screen the most promising TBC compositions; perform material characterizations and oxidation/corrosion tests; and demonstrate our new thermal barrier coating (TBC) systems experimentally under integrated gasification combined cycle (IGCC) environments.

  5. Thermal and Environmental Barrier Coatings for Advanced Propulsion Engine Systems

    NASA Technical Reports Server (NTRS)

    Zhu, Dong-Ming; Miller, Robert A.

    2004-01-01

    Ceramic thermal and environmental barrier coatings (TEBCs) are used in gas turbine engines to protect engine hot-section components in the harsh combustion environments, and extend component lifetimes. For future high performance engines, the development of advanced ceramic barrier coating systems will allow these coatings to be used to simultaneously increase engine operating temperature and reduce cooling requirements, thereby leading to significant improvements in engine power density and efficiency. In order to meet future engine performance and reliability requirements, the coating systems must be designed with increased high temperature stability, lower thermal conductivity, and improved thermal stress and erosion resistance. In this paper, ceramic coating design and testing considerations will be described for high temperature and high-heat-flux engine applications in hot corrosion and oxidation, erosion, and combustion water vapor environments. Further coating performance and life improvements will be expected by utilizing advanced coating architecture design, composition optimization, and improved processing techniques, in conjunction with modeling and design tools.

  6. Computational Design and Experimental Validation of New Thermal Barrier Systems

    SciTech Connect

    Guo, Shengmin; Yang, Shizhong; Khosravi, Ebrahim

    2012-10-01

    This project (10/01/2010-9/30/2013), “Computational Design and Experimental Validation of New Thermal Barrier Systems”, originates from Louisiana State University (LSU) Mechanical Engineering Department and Southern University (SU) Department of Computer Science. This project will directly support the technical goals specified in DEFOA- 0000248, Topic Area 3: Turbine Materials, by addressing key technologies needed to enable the development of advanced turbines and turbine-based systems that will operate safely and efficiently using coal-derived synthesis gases. We will develop and implement novel molecular dynamics method to improve the efficiency of simulation on novel TBC materials; perform high performance computing (HPC) on complex TBC structures to screen the most promising TBC compositions; perform material characterizations and oxidation/corrosion tests; and demonstrate our new thermal barrier coating (TBC) systems experimentally under integrated gasification combined cycle (IGCC) environments. The durability of the coating will be examined using the proposed Durability Test Rig.

  7. Barriers And Motivators for Smoking Cessation in Patients With Systemic Lupus Erythematosus (SLE).

    PubMed

    Terrell, Deirdra R; Stewart, Lauren M; Tolma, Eleni L; McClain, Rebekah; Vesely, Sara K; James, Judith A

    2015-11-01

    Although studies have shown that smoking is detrimental to the health of patients with systemic lupus erythematosus (SLE), studies regarding barriers and motivators for smoking cessation are lacking. The purpose of this study was to generate hypotheses regarding the barriers and motivators for smoking cessation in SLE patients. This study was based on the theoretical framework of the stages of change model. All participants met SLE classification criteria. Interviews were conducted with 16 current and 10 former smokers. Motivators included: medical reasons, readiness, and concern for others. Barriers included: enjoyment, coping mechanism, and an emotional connection. Participants were unsure of the impact of smoking on their medication and disease, and had mixed feelings regarding the impact on pain. The main motivator for cessation in this population was concern for one's health. Rheumatologists need to include disease specific harms and assess pain management strategies as part of cessation counseling.

  8. Base Intrusion Schottky Barrier IR Assessment Camera Study.

    DTIC Science & Technology

    1981-09-01

    detection line sensors. The program includes coverage studies to determine requirements for array size and camera complexity to provide cost-effective...addition, hardware studies are being conducted to determine design requirements and specifications for development and for future field testing of an...Since the early 1970s, RCA has been actively engaged in the development of IRI Schottky barrier line and area FPAs for the Air Force RADC Deputy for

  9. Evaluation of Oxidation Damage in Thermal Barrier Coating Systems

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Miller, Robert A.

    1996-01-01

    A method based on the technique of dilatometry has been established to quantitatively evaluate the interfacial damage due to the oxidation in a thermal barrier coating system. Strain isolation and adhesion coefficients have been proposed to characterize the thermal barrier coating (TBC) performance based on its thermal expansion behavior. It has been found that, for a thermal barrier coating system consisting of ZrO2-8%Y2O3/FeCrAlY/4140 steel substrate, the oxidation of the bond coat and substrate significantly reduced the ceramic coating adherence, as inferred from the dilatometry measurements. The in-situ thermal expansion measurements under 30 deg C to 700 deg C thermal cycling in air showed that the adhesion coefficient, A(sub i) decreased by 25% during the first 35 oxidation cycles. Metallography showed that delamination occurred at both the ceramic/bond coat and bond coat/substrate interfaces. In addition, the strain isolation effect has been improved by increasing the FeCrAlY bond coat thickness. The strain isolation coefficient, Si, increased from about 0.04 to 0.25, as the bond coat thickness changed from 0.1 mm to 1.0 mm. It may be possible to design optimum values of strain isolation and interface adhesion coefficients to achieve the best TBC performance.

  10. TRITIUM BARRIER MATERIALS AND SEPARATION SYSTEMS FOR THE NGNP

    SciTech Connect

    Sherman, S; Thad Adams, T

    2008-07-17

    Contamination of downstream hydrogen production plants or other users of high-temperature heat is a concern of the Next Generation Nuclear Plant (NGNP) Project. Due to the high operating temperatures of the NGNP (850-900 C outlet temperature), tritium produced in the nuclear reactor can permeate through heat exchangers to reach the hydrogen production plant, where it can become incorporated into process chemicals or the hydrogen product. The concentration limit for tritium in the hydrogen product has not been established, but it is expected that any future limit on tritium concentration will be no higher than the air and water effluent limits established by the NRC and the EPA. A literature survey of tritium permeation barriers, capture systems, and mitigation measures is presented and technologies are identified that may reduce the movement of tritium to the downstream plant. Among tritium permeation barriers, oxide layers produced in-situ may provide the most suitable barriers, though it may be possible to use aluminized surfaces also. For tritium capture systems, the use of getters is recommended, and high-temperature hydride forming materials such as Ti, Zr, and Y are suggested. Tritium may also be converted to HTO in order to capture it on molecular sieves or getter materials. Counter-flow of hydrogen may reduce the flux of tritium through heat exchangers. Recommendations for research and development work are provided.

  11. Computational design and experimental validation of new thermal barrier systems

    SciTech Connect

    Guo, Shengmin

    2015-03-31

    The focus of this project is on the development of a reliable and efficient ab initio based computational high temperature material design method which can be used to assist the Thermal Barrier Coating (TBC) bond-coat and top-coat design. Experimental evaluations on the new TBCs are conducted to confirm the new TBCs’ properties. Southern University is the subcontractor on this project with a focus on the computational simulation method development. We have performed ab initio density functional theory (DFT) method and molecular dynamics simulation on screening the top coats and bond coats for gas turbine thermal barrier coating design and validation applications. For experimental validations, our focus is on the hot corrosion performance of different TBC systems. For example, for one of the top coatings studied, we examined the thermal stability of TaZr2.75O8 and confirmed it’s hot corrosion performance.

  12. Work system barriers to patient, provider, and caregiver use of personal health records: A systematic review.

    PubMed

    Thompson, Morgan J; Reilly, Jeremiah D; Valdez, Rupa S

    2016-05-01

    This review applied a human factors/ergonomics (HF/E) paradigm to assess individual, work system/unit, organization, and external environment factors generating barriers to patient, provider, and informal caregiver personal health record (PHR) use. The literature search was conducted using five electronic databases for the timeframe January 2000 to October 2013, resulting in 4865 citations. Two authors independently coded included articles (n = 60). Fifty-five, ten and five articles reported barriers to patient, provider and caregiver PHR use, respectively. Barriers centered around 20 subfactors. The most frequently noted were needs, biases, beliefs, and mood (n = 35) and technology functions and features (n = 32). The HF/E paradigm was effective in framing the assessment of factors creating barriers to PHR use. Design efforts should address literacy, interoperability, access to health information, and secure messaging. A deeper understanding of the interactions between work systems and the role of organization and external environment factors is required. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  13. Model assessment of protective barriers: Part 4, Status of FY 1992 work

    SciTech Connect

    Fayer, M.J.

    1993-03-01

    Protective barriers are being considered for use at the Hanford Site to enhance the isolation of radioactive wastes from water, plant, and animal intrusion. This study is part of an ongoing effort to assess the effectiveness of protective barriers for isolation of wastes from water. Part I of this study was the original modeling assessment by Pacific Northwest Laboratory of various protective barrier designs (e.g., soil type, vegetation). In Part 11 of this study, additional barrier designs were reviewed and several barrier modeling assumptions were tested. A test plan was then produced that detailed the requirement for hydrologic modeling of protective barriers. Part III of this study summarized the status of work in FY 1990 dealing with two-dimensional flow beneath the barrier and with validation testing using lysimeter data. This report (Part IV) addresses the application of a calibrated model to a much longer data set, the application of the calibrated model to a lysimeter that received a different treatment, and the effect of hysteresis on the behavior of water in the protective barrier.

  14. Assessing Controls on the Geometry and Dimensions of Modern Barrier Islands

    NASA Astrophysics Data System (ADS)

    Mulhern, J.; Johnson, C. L.; Martin, J. M.

    2015-12-01

    Barrier islands are highly ephemeral features, shaped by wave, tide, and storm energy. The processes that govern the size, shape, and motion of barrier islands are not well constrained, yet central to coastal dynamics. While the global distribution of barrier islands has been mapped and assessed, there is little consensus on the forces controlling barrier island formation, motion, or preservation. This study presents a new semi-global database of modern barrier islands to better understand their morphology and spatial distribution. We have mapped, in Google Earth, the subaerial extent of >350 barrier islands and spits, measuring spatial characteristic such as exposed area, perimeter, length, and width. These objects are cross-referenced with parameters that potentially control morphology, including tidal range, wave height, climate, distance from the continental shelf, proximity to fluvial output, and tectonic setting. This approach provides a more optimal framework to assess controls on coastal features, including barrier island morphology, and to investigate potential geometric scaling relationships. Preliminary analysis shows trends in the spatial characteristics of barrier islands. There is a strong linear relationship between the perimeter and length (y= -0.59 + 0.42x, R2=0.95). Linear trends also relate length to area when the data are separated by tidal range to wave height ratio. Assessment of barrier island shape supports the hypothesis of Hayes (1979) that barrier islands in wave-dominated settings are long and linear while those in mixed energy setting are more rounded. The barrier islands of the Texas Gulf of Mexico are larger than the global average for the database, with distinctly longer length values (41.16 km vs. 15.77 km respectively) and larger areas (103.81 km2 vs. 42.14 km2 respectively). Initial assessment shows that tidal range and wave height are primary controls barrier island dimensions. Future work will consider climate, latitude, fluvial

  15. Assessing Barrier Island Resiliency Through Multi-Scale Topographic Anisotropy Distribution Patterns

    NASA Astrophysics Data System (ADS)

    Lehner, J. D.; Wernette, P. A.; Bishop, M. P.; Houser, C.

    2016-12-01

    The resiliency of a barrier island, its ability to return to form and ecological function after storms, is of key scientific importance with further climate change and sea level rise. Response depends on relative height of the storm surge and the dunes, both heavily influenced by anthropogenic activities. Barrier island morphology and the anisotropic nature of barrier islands highlights the complexities of topographic evolution. Understanding this evolution is critical for assessing how barrier islands respond and recover through time. The purpose of this research is to assess the scale-dependent distribution patterns of topographic anisotropy to characterize changes in process regime influences (i.e., wind dominated, wave dominated, current dominated) and barrier island resiliency. The method presented is an evaluation of the scale-dependence of topographic relief and symmetry for multi-temporal LiDAR-derived DEMs of Padre Island National Seashore. We do not assume topographic symmetry in computing directional-dependence of the minimum relief. We generate false-color composite images of anisotropy parameters to examine scale-dependent relief, terrain orientation and symmetry patterns for multiple years. Results demonstrate that beaches, washover channels, foredunes, and back-barrier regions exhibit unique distribution patterns of terrain orientation and symmetry. Multi-temporal patterns of anisotropy parameters reveal variations in the spatial and temporal complexity of barrier island evolution. Consequently, it is possible to identify and map barrier island locations that are stable, recovering, or failing to recover. Objective spatial delineation of these areas can potentially be used to assess the polygenetic evolution of barrier island topography, thereby providing scientists with a better understanding of how coastal process regimes influence barrier island resiliency.

  16. Methodology for assessing systems materials requirements

    SciTech Connect

    Culver, D.H.; Teeter, R.R.; Jamieson, W.M.

    1980-01-01

    A potential stumbling block to new system planning and design is imprecise, confusing, or contradictory data regarding materials - their availability and costs. A methodology is now available that removes this barrier by minimizing uncertainties regarding materials availability. Using this methodology, a planner can assess materials requirements more quickly, at lower cost, and with much greater confidence in the results. Developed specifically for energy systems, its potential application is much broader. This methodology and examples of its use are discussed.

  17. Assessment of diaper-clogging potential of petrolatum moisture barriers.

    PubMed

    Zehrer, Cindy L; Newman, Diane K; Grove, Gary L; Lutz, James B

    2005-12-01

    Petrolatum-based ointments often are used to treat and prevent incontinence dermatitis. However, anecdotal reports indicate that petrolatum ointments may affect the absorbency of disposable briefs also commonly used in incontinence management. To examine whether petrolatum ointments clog a commonly used absorbent brief, a randomized, balanced-block design study was conducted in a controlled laboratory setting to compare the brief-clogging potential of three petrolatum ointments to a non-alcohol barrier film. Test products were applied to 6-cm x 6-cm test sites on the volar forearms of 16 volunteers. Pre-weighed mini briefs were applied to the test sites in a manner that simulates normal brief wear. After 5 minutes of wear, the mini briefs were weighed to determine percent of product transfer from skin to mini brief. The mini briefs then were reapplied to the same test sites and a synthetic urine solution was introduced between the skin and the mini brief. Mini briefs subsequently were removed to determine fluid uptake by weight. Results indicate significant differences between the four test products (P < 0.01) both in percent transfer and in mini brief fluid absorption. From 59% to 69% of the petrolatum-based products transferred from the skin to the mini briefs and a 54% to 90% reduction in fluid uptake was noted, as determined by weight. The non-alcohol barrier film did not transfer to the mini brief and fluid uptake was minimally affected. Further study in the clinical and practice settings to determine the effect and consequences of barrier product transfer on absorbent garments is warranted.

  18. Onboard System Health Assessment

    NASA Technical Reports Server (NTRS)

    Barry, Tom; Cunningham, Harry

    1990-01-01

    Viewgraphs and discussion of onboard system health assessment are presented. Success of the space station program will be measured by how well it addresses the basic requirements for (1) maintaining the orbiting Space Station Freedom fully operational for its projected life of thirty years, and (2) the cost-effective execution of the overall space station program. Onboard system health assessment must provide complete and thorough testing capabilities along with effective associated redundancy/fault management.

  19. Thermophysical and Thermomechanical Properties of Thermal Barrier Coating Systems

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Miller, Robert A.

    2000-01-01

    Thermal barrier coatings have been developed for advanced gas turbine and diesel engine applications to improve engine reliability and fuel efficiency. However, the issue of coating durability under high temperature cyclic conditions is still of major concern. The coating failure is closely related to thermal stresses and oxidation in the coating systems. Coating shrinkage cracking resulting from ceramic sintering and creep at high temperatures can further accelerate the coating failure process. The purpose of this paper is to address critical issues such as ceramic sintering and creep, thermal fatigue and their relevance to coating life prediction. Novel test approaches have been established to obtain critical thermophysical and thermomechanical properties of the coating systems under near-realistic temperature and stress gradients encountered in advanced engine systems. Emphasis is placed on the dynamic changes of the coating thermal conductivity and elastic modulus, fatigue and creep interactions, and resulting failure mechanisms during the simulated engine tests. Detailed experimental and modeling results describing processes occurring in the thermal barrier coating systems provide a framework for developing strategies to manage ceramic coating architecture, microstructure and properties.

  20. Microstructural Evolution and Interfacial Motion in Systems with Diffusion Barriers

    SciTech Connect

    William C. Johnson

    2007-06-30

    The initial goal of this research program was to model and to simulate phase transformations in systems containing diffusion barriers. The modeling work included the development and testing of code to describe mass flow, the kinetics of phase formation, elastic deformation, and subsequent microstructural evolution occurring during interdiffusion. The primary simulation tools to be used were a class of diffuse interface methods described by the Cahn-Hilliard and phase field equations for the temporal and spatial evolution of the composition and deformation fields and other relevant phase variables. One-dimensional analytical solutions were also to be developed both to test the numerical methods and to establish connections to physical systems. During the early stages of the research program, two new areas of research related to systems with diffusion barriers were identified. The first area concerned phase formation and diffusional phase transformations in reacting systems subject to high electric current densities. Such high-current environments are common in lead-free solders, for example, and have important technological applications. The second area was an offshoot of the present work, and concerned theoretical modeling of phase evolution and cyclical amorphization of metallic alloys during ball milling.

  1. Towards a barrier height benchmark set for biologically relevant systems

    PubMed Central

    Kromann, Jimmy C.; Christensen, Anders S.; Cui, Qiang

    2016-01-01

    We have collected computed barrier heights and reaction energies (and associated model structures) for five enzymes from studies published by Himo and co-workers. Using this data, obtained at the B3LYP/6- 311+G(2d,2p)[LANL2DZ]//B3LYP/6-31G(d,p) level of theory, we then benchmark PM6, PM7, PM7-TS, and DFTB3 and discuss the influence of system size, bulk solvation, and geometry re-optimization on the error. The mean absolute differences (MADs) observed for these five enzyme model systems are similar to those observed for PM6 and PM7 for smaller systems (10–15 kcal/mol), while DFTB results in a MAD that is significantly lower (6 kcal/mol). The MADs for PMx and DFTB3 are each dominated by large errors for a single system and if the system is disregarded the MADs fall to 4–5 kcal/mol. Overall, results for the condensed phase are neither more or less accurate relative to B3LYP than those in the gas phase. With the exception of PM7-TS, the MAD for small and large structural models are very similar, with a maximum deviation of 3 kcal/mol for PM6. Geometry optimization with PM6 shows that for one system this method predicts a different mechanism compared to B3LYP/6-31G(d,p). For the remaining systems, geometry optimization of the large structural model increases the MAD relative to single points, by 2.5 and 1.8 kcal/mol for barriers and reaction energies. For the small structural model, the corresponding MADs decrease by 0.4 and 1.2 kcal/mol, respectively. However, despite these small changes, significant changes in the structures are observed for some systems, such as proton transfer and hydrogen bonding rearrangements. The paper represents the first step in the process of creating a benchmark set of barriers computed for systems that are relatively large and representative of enzymatic reactions, a considerable challenge for any one research group but possible through a concerted effort by the community. We end by outlining steps needed to expand and improve the data

  2. Enhanced TEX biodegradation in nutrient briquet-peat barrier system

    SciTech Connect

    Kao, C.M.; Borden, R.C.

    1997-01-01

    A two-layer barrier system has been developed to remediate gasoline-contaminated ground water. This system consists of a nutrient briquet layer to continuously supply nitrate as the electron acceptor for contaminant biodegradation and a peat layer to remove residual nitrate via biological denitrification and residual contaminants by sorption. Nitrate release rates from three different sizes of concrete briquets were used to estimate parameters for modeling solute diffusion in aggregated porous media with mobile and stagnant porewater regions. Toluene, ethylbenzene, and xylene (TEX) biodegradation rates in denitrifying microcosms at pH 8 and 9 were lower than in microcosms at pH 7.4. No degradation was observed at pH 10 under denitrifying conditions. A laboratory-scale, permeable barrier system was developed to evaluate TEX removal and to identify any operational problems. Average removal efficiencies were 86% for toluene, 71% for ethylbenzene, 43% for m-xylene, and 28% for o-xylene in the nutrient briquet and downstream soil column over a 45-day operating period. There was no evidence of benzene biodegradation under denitrifying conditions in the batch microcosms or continuous-flow columns.

  3. Acoustic emission assessment of interface cracking in thermal barrier coatings

    NASA Astrophysics Data System (ADS)

    Yang, Li; Zhong, Zhi-Chun; Zhou, Yi-Chun; Zhu, Wang; Zhang, Zhi-Biao; Cai, Can-Ying; Lu, Chun-Sheng

    2016-04-01

    In this paper, acoustic emission (AE) and digital image correlation methods were applied to monitor interface cracking in thermal barrier coatings under compression. The interface failure process can be identified via its AE features, including buckling, delamination incubation and spallation. According to the Fourier transformation of AE signals, there are four different failure modes: surface vertical cracks, opening and sliding interface cracks, and substrate deformation. The characteristic frequency of AE signals from surface vertical cracks is 0.21 MHz, whilst that of the two types of interface cracks are 0.43 and 0.29 MHz, respectively. The energy released of the two types of interface cracks are 0.43 and 0.29 MHz, respectively. Based on the energy released from cracking and the AE signals, a relationship is established between the interface crack length and AE parameters, which is in good agreement with experimental results.

  4. Self-care Barriers Reported by Emergency Department Patients With Acute Heart Failure: A Sociotechnical Systems-based Approach

    PubMed Central

    Holden, Richard J.; Schubert, Christiane C.; Eiland, Eugene C.; Storrow, Alan B.; Miller, Karen F.; Collins, Sean P.

    2015-01-01

    Objective To pilot a sociotechnical systems-based instrument that assesses the prevalence and nature of self-care barriers among patients presenting to the emergency department (ED) with acute heart failure. Methods A semi-structured instrument for measuring self-reported self-care barriers was developed and administered by ED clinicians and non-clinician researchers to 31 ED patients diagnosed with acute heart failure. Responses were analyzed using descriptive statistics and qualitative content analysis. Feasibility was assessed by examining participant cooperation rates, instrument completion times, item nonresponse, and data yield. Results Of 47 distinct self-care barriers assessed, a median of 15 per patient were indicated as “sometimes” or “often” present. Thirty-four specific barriers were reported by over 25% of patients and nine were reported by over 50%. The sources of barriers included the person, self-care tasks, tools and technologies, and organizational, social, and physical contexts. Seven of the top ten most prevalent barriers were related to patient characteristics and the next three to the organizational context (e.g., life disruptions). A preliminary feasibility assessment found few item nonresponses or comprehension difficulties, good cooperation, high data yield from both closed- and open-ended items, but opportunities to reduce median administration time and variability. Conclusions An instrument assessing self-care barriers from multiple system sources can be feasibly implemented in the ED. Further research is required to modify the instrument for widespread use and evaluate its implementation across institutions and cultural contexts. Self-care barriers measurement can be one component of broader inquiry into the distributed health-related “work” activity of patients, caregivers, and clinicians. PMID:25616317

  5. Real-World Barriers to Assessing and Treating Mental Health Problems With IPV Survivors: A Qualitative Study.

    PubMed

    Simmons, Catherine A; Lindsey, Leslie; Delaney, Matthew J; Whalley, Anna; Beck, J Gayle

    2015-07-01

    Barriers to assessing and treating mental health problems with intimate partner violence (IPV) survivors were identified with qualitative responses from 62 IPV helping professionals who participated in an online survey question. Data were analyzed using a concept mapping approach, which resulted in following eight distinct clusters: (a) unsure, (b) limited IPV specific resources, (c) barriers to access, (d) systems-taboos, (e) immediate crisis needs, (f) fear-stigma, (g) offender's control and (h) cultural concerns. The opinions expressed in these clusters help to better explain logistic, relational, and intrapersonal obstacles that can limit women IPV survivors' ability to receive care for mental health conditions. Extending previous quantitative work by the authors (Simmons, Whalley, & Beck, 2014), the current portion of this project generates new ways of looking at barriers to service delivery, which can be used to develop theory and guide further research.

  6. Failure Mechanism for Thermal Fatigue of Thermal Barrier Coating Systems

    NASA Astrophysics Data System (ADS)

    Giolli, C.; Scrivani, A.; Rizzi, G.; Borgioli, F.; Bolelli, G.; Lusvarghi, L.

    2009-06-01

    Thick thermal barrier coatings (TBCs), consisting of a CoNiCrAlY bond coat and yttria-partially stabilized zirconia top coat with different porosity values, were produced by air plasma spray (APS). The thermal fatigue resistance limit of the TBCs was tested by furnace cycling tests (FCT) according to the specifications of an original equipment manufacturer (OEM). The morphology, residual stresses, and micromechanical properties (microhardness, indentation fracture toughness) of the TBC systems before and after FCT were analyzed. The thermal fatigue resistance increases with the amount of porosity in the top coat. The compressive in-plane stresses increase in the TBC systems after thermal cycling; nevertheless the increasing rate has a trend contrary to the porosity level of top coat. The data suggest that the spallation happens at the TGO/top coat interface. The failure mechanism of thick TBCs was found to be similar to that of conventional thin TBC systems made by APS.

  7. Computational Design and Experimental Validation of New Thermal Barrier Systems

    SciTech Connect

    Guo, Shengmin; Yang, Shizhong; Khosravi, Ebrahim

    2011-12-31

    This project (10/01/2010-9/30/2013), “Computational Design and Experimental Validation of New Thermal Barrier Systems”, originates from Louisiana State University (LSU) Mechanical Engineering Department and Southern University (SU) Department of Computer Science. This proposal will directly support the technical goals specified in DE-FOA-0000248, Topic Area 3: Turbine Materials, by addressing key technologies needed to enable the development of advanced turbines and turbine-based systems that will operate safely and efficiently using coal-derived synthesis gases. We will develop novel molecular dynamics method to improve the efficiency of simulation on novel TBC materials; we will perform high performance computing (HPC) on complex TBC structures to screen the most promising TBC compositions; we will perform material characterizations and oxidation/corrosion tests; and we will demonstrate our new Thermal barrier coating (TBC) systems experimentally under Integrated gasification combined cycle (IGCC) environments. The durability of the coating will be examined using the proposed High Temperature/High Pressure Durability Test Rig under real syngas product compositions.

  8. Scientific investigation plan for initial engineered barrier system field tests

    SciTech Connect

    Wunan Lin

    1993-02-01

    The purpose of this Scientific Investigation Plan (SIP) is to describe tests known as Initial Engineered Barrier System Field Tests (IEBSFT) and identified by Work Breakdown Structure as WBS 1.2.2.2.4. The IEBSFT are precursors to the Engineered Barrier System Field Test (EBSFT), WBS 1.2.2.2.4, to be conducted in the Exploratory Study Facility (ESF) at Yucca Mountain. The EBSFT and IEBSFT are designed to provide information on the interaction between waste packages (simulated by heated containers) and the surrounding rock mass, its vadose water, and infiltrated water. Heater assemblies will be installed in drifts or boreholes openings and heated to measure moisture movement during heat-up and subsequent cool-down of the rock mass. In some of the tests, infiltration of water into the heated rock mass will be studied. Throughout the heating and cooling cycle, instruments installed in the rock will monitor such parameters as temperature, moisture content, concentration of some chemical species, and stress and strain. Rock permeability measurements, rock and fluid (water and gas) sampling, and fracture pattern measurements will also be made before and after the test.

  9. The Community Assessment System.

    ERIC Educational Resources Information Center

    Haynes, Alan E.

    The Community Assessment System (CAS) is a research technique designed to probe small, rural community perceptions and attitudes toward planned economic expansion and social development by generating suggestions for general or specific community modifications; ascertaining community attitudes and possible responses to a specific modification;…

  10. Isothermal and cyclic oxidation of an air plasma-sprayed thermal barrier coating system

    SciTech Connect

    Haynes, J.A.; Ferber, M.K.; Porter, W.D.; Rigney, E.D.

    1996-08-01

    Thermogravimetric methods for evaluating bond coat oxidation in plasma-sprayed thermal barrier coating (TBC) systems were assessed by high-temperature testing of TBC systems with air plasma-sprayed (APS) Ni-22Cr-10Al-1Y bond coatings and yttria-stabilized zirconia top coatings. High-mass thermogravimetric analysis (at 1150{sup degrees}C) was used to measure bond coat oxidation kinetics. Furnace cycling was used to evaluate APS TBC durability. This paper describes the experimental methods and relative oxidation kinetics of the various specimen types. Characterization of the APS TBCs and their reaction products is discussed.

  11. Removal of bacteria, protozoa and viruses through a multiple-barrier household water disinfection system.

    PubMed

    Espinosa-García, A C; Díaz-Ávalos, C; Solano-Ortiz, R; Tapia-Palacios, M A; Vázquez-Salvador, N; Espinosa-García, S; Sarmiento-Silva, R E; Mazari-Hiriart, M

    2014-03-01

    Municipal water disinfection systems in some areas are not always able to meet water consumer needs, such as ensuring distributed water quality, because household water management can be a contributing factor in water re-contamination. This fact is related to the storage options that are common in places where water is scarce or is distributed over limited time periods. The aim of this study is to assess the removal capacity of a multiple-barrier water disinfection device for protozoa, bacteria, and viruses. Water samples were taken from households in Mexico City and spiked with a known amount of protozoa (Giardia cyst, Cryptosporidium oocyst), bacteria (Escherichia coli), and viruses (rotavirus, adenovirus, F-specific ribonucleic acid (FRNA) coliphage). Each inoculated sample was processed through a multiple-barrier device. The efficiency of the multiple-barrier device to remove E. coli was close to 100%, and more than 87% of Cryptosporidium oocysts and more than 98% of Giardia cysts were removed. Close to 100% of coliphages were removed, 99.6% of the adenovirus was removed, and the rotavirus was almost totally removed. An effect of site by zone was detected; this observation is important because the water characteristics could indicate the efficiency of the multiple-barrier disinfection device.

  12. Qualitative Assessment across Language Barriers: An Action Research Study

    ERIC Educational Resources Information Center

    Cronje, Johannes C.

    2009-01-01

    If students cannot express themselves in the language of the assessor, and if the assessor is not familiar with the cultural constraints within which students operate, it is difficult for the assessor to collect evidence of adequate performance. This article describes the assessment of three digital artefacts where the assessor strove to…

  13. Risk Assessment System

    NASA Technical Reports Server (NTRS)

    1993-01-01

    FEAT, a software system for evaluating risks, was developed by Lockheed and later enhanced under NASA funding. FEAT uses directed graph - or digraph - models to provide information on cause and effect if a set of failure events occurs. James Miller, the program designer at Lockheed, formed DiGraphics, Inc. to market the software that has evolved from FEAT. The Diquest Analyzer, the company's flagship product, assists product designers in identifying the redundancies and weaknesses of a system. The software has applications in the chemical industry for risk assessment, design evaluation, and change management. Additional markets have been found in operations monitoring diagnostics and training of new personnel.

  14. Advanced thermal barrier coating system development. Technical progress report, June 1, 1996--July 31, 1996

    SciTech Connect

    1996-08-07

    An improved thermal barrier coating system with good reliability and thermal performance is described. The report discusses the coating process, manufacturing, repair, deposition, and microstructure of the coatings.

  15. CEMENTITIOUS BARRIERS MODELING FOR PERFORMANCE ASSESSMENTS OF SHALLOW LAND BURIAL OF LOW LEVEL RADIOACTIVE WASTE - 9243

    SciTech Connect

    Taylor, G

    2009-01-09

    The Cementitious Barriers Partnership (CBP) was created to develop predictive capabilities for the aging of cementitious barriers over long timeframes. The CBP is a multi-agency, multi-national consortium working under a U.S. Department of Energy (DOE) Environmental Management (EM-21) funded Cooperative Research and Development Agreement (CRADA) with the Savannah River National Laboratory (SRNL) as the lead laboratory. Members of the CBP are SRNL, Vanderbilt University, the U.S. Nuclear Regulatory Commission (USNRC), National Institute of Standards and Technology (NIST), SIMCO Technologies, Inc. (Canada), and the Energy Research Centre of the Netherlands (ECN). A first step in developing advanced tools is to determine the current state-of-the-art. A review has been undertaken to assess the treatment of cementitious barriers in Performance Assessments (PA). Representatives of US DOE sites which have PAs for their low level waste disposal facilities were contacted. These sites are the Idaho National Laboratory, Oak Ridge National Laboratory, Los Alamos National Laboratory, Nevada Test Site, and Hanford. Several of the more arid sites did not employ cementitious barriers. Of those sites which do employ cementitious barriers, a wide range of treatment of the barriers in a PA was present. Some sites used conservative, simplistic models that even though conservative still showed compliance with disposal limits. Other sites used much more detailed models to demonstrate compliance. These more detailed models tend to be correlation-based rather than mechanistically-based. With the US DOE's Low Level Waste Disposal Federal Review Group (LFRG) moving towards embracing a risk-based, best estimate with an uncertainties type of analysis, the conservative treatment of the cementitious barriers seems to be obviated. The CBP is creating a tool that adheres to the LFRG chairman's paradigm of continuous improvement.

  16. Expertise, Time, Money, Mentoring, and Reward: Systemic Barriers That Limit Education Researcher Productivity-Proceedings From the AAMC GEA Workshop.

    PubMed

    Yarris, Lalena M; Juve, Amy Miller; Artino, Anthony R; Sullivan, Gail M; Rougas, Steven; Joyce, Barbara; Eva, Kevin

    2014-09-01

    To further evolve in an evidence-based fashion, medical education needs to develop and evaluate new practices for teaching, learning, and assessment. However, educators face barriers in designing, conducting, and publishing education research. To explore the barriers medical educators face in formulating, conducting, and publishing high-quality medical education research, and to identify strategies for overcoming them. A consensus workshop was held November 5, 2013, at the Association of American Medical Colleges annual meeting. A working group of education research experts and educators completed a preconference literature review focusing on barriers to education research. During the workshop, consensus-based and small group techniques were used to refine the broad themes into content categories. Attendees then ranked the most important barriers and strategies for overcoming them with the highest potential impact. Barriers participants faced in conducting quality education research included lack of (1) expertise, (2) time, (3) funding, (4) mentorship, and (5) reward. The strategy considered most effective in overcoming these barriers involved building communities of education researchers for collaboration and networking, and advocating for education researchers' interests. Other suggestions included trying to secure increased funding opportunities, developing mentoring programs, and encouraging mechanisms to ensure protected time. Barriers to education research productivity clearly exist. Many appear to result from feelings of isolation that may be overcome with systemic efforts to develop and enable communities of practice across institutions. Finally, the theme of "reward" is novel and complex and may have implications for education research productivity.

  17. Assessing a landscape barrier using genetic simulation modelling: implications for raccoon rabies management.

    PubMed

    Rees, Erin E; Pond, Bruce A; Cullingham, Catherine I; Tinline, Rowland; Ball, David; Kyle, Christopher J; White, Bradley N

    2008-08-15

    Landscape barriers influence movement patterns of animals, which in turn, affect spatio-temporal spread of infectious wildlife disease. We compare genetic data from computer simulations to those acquired from field samples to measure the effect of a landscape barrier on raccoon (Procyon lotor) movement, enabling risk assessment of raccoon rabies disease spread across the Niagara River from New York State into Ontario, an area currently uninfected by rabies. An individual-based spatially explicit model is used to simulate the expansion of a raccoon population to cross the Niagara River, for different permeabilities of the river to raccoon crossings. Since the model records individual raccoon genetics, the genetic population structure of neutral mitochondrial DNA haplotypes are characterised in the expanding population, every 25 years, using a genetic distance measure, phi ST, Mantel tests and a gene diversity measure. The river barrier effect is assessed by comparing genetic measures computed from model outputs to those calculated from 166 raccoons recently sampled from the same landscape. The "best fit" between modelled scenarios and field data indicate the river prevents 50% of attempts to cross the river. Founder effects dominated the colonizing genetic population structure, and, as the river barrier effect increased, its genetic diversity decreased. Using gene flow to calibrate the effect of the river as a barrier to movement provides an estimate of the effect of a river in reducing the likelihood of cross-river infection. Including individual genetic markers in simulation modelling benefits investigations of disease spread and control.

  18. The Impact of Assessment for Learning: Benefits and Barriers to Student Achievement

    ERIC Educational Resources Information Center

    Collins, Natalie M.

    2012-01-01

    The purpose of this study was to compare growth in student achievement of students in a classroom where the assessment for learning process was either absent from or present in a teacher's practices, and to gather the teacher's and students' perceptions of the benefits and barriers related to growth in student achievement when the…

  19. Creating an Outcomes-Based Tool for Learning Barrier Assessment in an Outpatient Education Program.

    ERIC Educational Resources Information Center

    Hernandez, Teri L.; Rupnow, Jana M.; Currie, Kristi A.; Procious, James K.; Adams, Jenny

    2003-01-01

    An outcomes-based assessment instrument was devised to screen patients for learning problems that would impede patient education in cardiac rehabilitation. Criteria for seven barriers were established: hearing, language, cultural, religious, vision, cognitive, emotional). Points of data collection and a rationale for collection were identified.…

  20. Identifying Barriers in Implementing Outcomes-Based Assessment Program Review: A Grounded Theory Analysis

    ERIC Educational Resources Information Center

    Bresciani, Marilee J.

    2011-01-01

    The purpose of this grounded theory study was to identify the typical barriers encountered by faculty and administrators when implementing outcomes-based assessment program review. An analysis of interviews with faculty and administrators at nine institutions revealed a theory that faculty and administrators' promotion, tenure (if applicable),…

  1. Creating an Outcomes-Based Tool for Learning Barrier Assessment in an Outpatient Education Program.

    ERIC Educational Resources Information Center

    Hernandez, Teri L.; Rupnow, Jana M.; Currie, Kristi A.; Procious, James K.; Adams, Jenny

    2003-01-01

    An outcomes-based assessment instrument was devised to screen patients for learning problems that would impede patient education in cardiac rehabilitation. Criteria for seven barriers were established: hearing, language, cultural, religious, vision, cognitive, emotional). Points of data collection and a rationale for collection were identified.…

  2. Nanoscale drug delivery systems and the blood–brain barrier

    PubMed Central

    Alyautdin, Renad; Khalin, Igor; Nafeeza, Mohd Ismail; Haron, Muhammad Huzaimi; Kuznetsov, Dmitry

    2014-01-01

    The protective properties of the blood–brain barrier (BBB) are conferred by the intricate architecture of its endothelium coupled with multiple specific transport systems expressed on the surface of endothelial cells (ECs) in the brain’s vasculature. When the stringent control of the BBB is disrupted, such as following EC damage, substances that are safe for peripheral tissues but toxic to neurons have easier access to the central nervous system (CNS). As a consequence, CNS disorders, including degenerative diseases, can occur independently of an individual’s age. Although the BBB is crucial in regulating the biochemical environment that is essential for maintaining neuronal integrity, it limits drug delivery to the CNS. This makes it difficult to deliver beneficial drugs across the BBB while preventing the passage of potential neurotoxins. Available options include transport of drugs across the ECs through traversing occludins and claudins in the tight junctions or by attaching drugs to one of the existing transport systems. Either way, access must specifically allow only the passage of a particular drug. In general, the BBB allows small molecules to enter the CNS; however, most drugs with the potential to treat neurological disorders other than infections have large structures. Several mechanisms, such as modifications of the built-in pumping-out system of drugs and utilization of nanocarriers and liposomes, are among the drug-delivery systems that have been tested; however, each has its limitations and constraints. This review comprehensively discusses the functional morphology of the BBB and the challenges that must be overcome by drug-delivery systems and elaborates on the potential targets, mechanisms, and formulations to improve drug delivery to the CNS. PMID:24550672

  3. Assessing thermal barrier coatings by eddy-current inversion

    NASA Astrophysics Data System (ADS)

    Sabbagh, Harold A.; Sabbagh, Elias H.; Kim Murphy, R.; Nyenhuis, John

    2002-05-01

    The nondestructive evaluation (NDE) of high-temperature coatings is one of the important factors in achieving a high level of structural integrity in advanced gas turbines. In this paper, we demonstrate that sophisticated eddy-current techniques can be utilized to measure the thickness and remaining-life of high-temperature coatings. We discuss the difficult in-service case, in which the time-temperature exposure of the combustion turbine blade has created a four-layered system, in addition to the base metal.

  4. Barriers and opportunities in assessing calls to emergency medical communication centre--a qualitative study.

    PubMed

    Lindström, Veronica; Heikkilä, Kristiina; Bohm, Katarina; Castrèn, Maaret; Falk, Ann-Charlotte

    2014-11-11

    Previous studies have described the difficulties and the complexity of assessing an emergency call, and assessment protocols intended to support the emergency medical dispatcher's (EMD) assessment have been developed and evaluated in recent years. At present, the EMD identifies about 50-70 % of patients suffering from cardiac arrest, acute myocardial infarction or stroke. The previous research has primarily been focused on specific conditions, and it is still unclear whether there are any overall factors that may influence the assessment of the call to the emergency medical communication centre (EMCC). The aim of the study was to identify overall factors influencing the registered nurses' (RNs) assessment of calls to the EMCC. A qualitative study design was used; a purposeful selection of calls to the EMCC was analysed by content analysis. One hundred calls to the EMCC were analysed. Barriers and opportunities related to the RN or the caller were identified as the main factors influencing the RN's assessment of calls to the EMCC. The opportunities appeared in the callers' symptom description and the communication strategies used by the RN. The barriers appeared in callers' descriptions of unclear symptoms, paradoxes and the RN's lack of communication strategies during the call. Barriers in assessing the call to the EMCC were associated with contradictory information, the absence of a primary problem, or the structure of the call. Opportunities were associated with a clear symptom description that was also repeated, and the RN's use of different communication strategies such as closed loop communication.

  5. Initial Assessment of Environmental Barrier Coatings for the Prometheus Project

    SciTech Connect

    M. Frederick

    2005-12-15

    Depending upon final design and materials selections, a variety of engineering solutions may need to be considered to avoid chemical degradation of components in a notional space nuclear power plant (SNPP). Coatings are one engineered approach that was considered. A comprehensive review of protective coating technology for various space-reactor structural materials is presented, including refractory metal alloys [molybdenum (Mo), tungsten (W), rhenium (Re), tantalum (Ta), and niobium (Nb)], nickel (Ni)-base superalloys, and silicon carbide (Sic). A summary description of some common deposition techniques is included. A literature survey identified coatings based on silicides or iridium/rhenium as the primary methods for environmental protection of refractory metal alloys. Modified aluminide coatings have been identified for superalloys and multilayer ceramic coatings for protection of Sic. All reviewed research focused on protecting structural materials from extreme temperatures in highly oxidizing conditions. Thermodynamic analyses indicate that some of these coatings may not be protective in the high-temperature, impure-He environment expected in a Prometheus reactor system. Further research is proposed to determine extensibility of these coating materials to less-oxidizing or neutral environments.

  6. Transition state theory for activated systems with driven anharmonic barriers

    NASA Astrophysics Data System (ADS)

    Revuelta, F.; Craven, Galen T.; Bartsch, Thomas; Borondo, F.; Benito, R. M.; Hernandez, Rigoberto

    2017-08-01

    Classical transition state theory has been extended to address chemical reactions across barriers that are driven and anharmonic. This resolves a challenge to the naive theory that necessarily leads to recrossings and approximate rates because it relies on a fixed dividing surface. We develop both perturbative and numerical methods for the computation of a time-dependent recrossing-free dividing surface for a model anharmonic system in a solvated environment that interacts strongly with an oscillatory external field. We extend our previous work, which relied either on a harmonic approximation or on periodic force driving. We demonstrate that the reaction rate, expressed as the long-time flux of reactive trajectories, can be extracted directly from the stability exponents, namely, Lyapunov exponents, of the moving dividing surface. Comparison to numerical results demonstrates the accuracy and robustness of this approach for the computation of optimal (recrossing-free) dividing surfaces and reaction rates in systems with Markovian solvation forces. The resulting reaction rates are in strong agreement with those determined from the long-time flux of reactive trajectories.

  7. Transition state theory for activated systems with driven anharmonic barriers.

    PubMed

    Revuelta, F; Craven, Galen T; Bartsch, Thomas; Borondo, F; Benito, R M; Hernandez, Rigoberto

    2017-08-21

    Classical transition state theory has been extended to address chemical reactions across barriers that are driven and anharmonic. This resolves a challenge to the naive theory that necessarily leads to recrossings and approximate rates because it relies on a fixed dividing surface. We develop both perturbative and numerical methods for the computation of a time-dependent recrossing-free dividing surface for a model anharmonic system in a solvated environment that interacts strongly with an oscillatory external field. We extend our previous work, which relied either on a harmonic approximation or on periodic force driving. We demonstrate that the reaction rate, expressed as the long-time flux of reactive trajectories, can be extracted directly from the stability exponents, namely, Lyapunov exponents, of the moving dividing surface. Comparison to numerical results demonstrates the accuracy and robustness of this approach for the computation of optimal (recrossing-free) dividing surfaces and reaction rates in systems with Markovian solvation forces. The resulting reaction rates are in strong agreement with those determined from the long-time flux of reactive trajectories.

  8. Assessment of permeability barriers to macromolecules in the rodent endometrium at the onset of implantation.

    PubMed

    Bany, Brent M; Hamilton, G Scot

    2011-01-01

    In rodents, embryo implantation is an invasive process, which begins with its attachment to the uterine wall and culminates in the formation of the definitive placenta several days later. It is critical that the endometrium provide a supportive environment for the implanting embryo during this process, as the placenta is not yet established. The concept of changing permeability barriers to macromolecules between different extracellular compartments in the rodent uterus at the onset of implantation has been established. This chapter provides protocols that can be used to assess this changing permeability barrier and the associated redistribution of macromolecules during the early phases of implantation in rodents. An increased permeability of the endometrial vasculature to plasma proteins occurs in areas adjacent to the implanting blastocyst. In addition, alterations in the extracellular matrix enhance the accumulation of fluid and extravasated macromolecules. We describe several protocols proven to be effective in studying and quantifying early vascular and extravascular responses to natural and artificial "implantation stimuli." The first three protocols represent qualitative and quantitative methods to assess the early endometrial "vascular permeability" response. On the contrary, the fourth protocol addresses the onset of decidualization and the arising permeability barrier, which restricts the movement of macromolecules through the extracellular space. This barrier is believed to provide transient protection for the implanting embryo against potentially harmful maternal serum proteins. This protocol describes assessment of resistance of the primary decidual zone to the movement of macromolecules across the compartments of the extracellular space.

  9. Indentation methods for adhesion measurement in thermal barrier coating systems

    NASA Astrophysics Data System (ADS)

    Ma, Qin

    This thesis investigates the fundamentals of indentation-induced delamination of electron beam physical vapor deposition thermal barrier coatings (EB-PVD TBCs). Thermal barrier coatings are thin ceramic coatings used to insulate gas turbine components. In the as-processed state, TBCs are well-bonded to the metallic substrate they are deposited upon. However, as these coatings are exposed to high temperatures during turbine operation, they lose their adhesion. The goal of this thesis is to determine how to use indentation testing techniques, coupled with fracture mechanics principles, to track this loss of adhesion and to identify mechanisms causing it. This thesis addresses four primary topics. First, a detailed fracture mechanics analysis of indentation-induced delamination is made, including the quantification of energy release rates, interfacial toughnesses and mode mix. The second topic addressed is application of the indentation test to track toughness losses in TBC systems subjected to a variety of thermal exposures. Three subtopics are included: (1) mechanism-based tests for the isothermal dry air exposures; (2) mechanism-based tests for exposures with water vapor and (3) mechanism-based tests for cyclic thermal exposures. In the first subtopic, TGO thickening and TBC sintering are modeled. Various mechanisms that lead to toughness degradation are discussed and analyzed quantitatively. An Arrhenius analysis has been performed to understand accelerated testing methods. The second subtopic presents the results of toughness degradation and the evolution of microstructures due to isothermal exposure with water vapor. The third subtopic investigates the toughness degradation for cyclic thermal exposures in dry air. Piezospectroscopy method has been applied to track the evolution of residual stresses in the TGO layer with thermal cycles. Quantitative analysis has been provided to give insights into the effects of oxide damage during thermal cycling. The final two

  10. Benchtop evaluation of pressure barrier insufflator and standard insufflator systems.

    PubMed

    Nepple, Kenneth G; Kallogjeri, Dorina; Bhayani, Sam B

    2013-01-01

    Previous experimental research has reported minimal differences in pressure maintenance between different versions of standard insufflators (SI). However, a recent report identified potential clinical benefits with a valveless pressure barrier insufflator (PBI). We sought to perform a benchtop objective evaluation of SI and PBI systems. A rigid box system with continuous pressure manometry was used to evaluate a PBI (Surgiquest Airseal) and two SIs (SI1 = Stryker PneumoSure High Flow Insufflator and SI2 = Storz SCB Thermoflator). Pressure maintenance of 15 mmHg was evaluated during experimental conditions of leakage from a 5 mm port site, leakage from a 12 mm port site, and continuous suction. With leakage from the 5 mm port site, the PBI maintained pressure of >13 mmHg whereas the pressures dropped moderately with the SI1 (7-13 mmHg) and SI2 insufflators (3-7 mmHg) and did not regain goal pressure until leakage was stopped. With leakage from 12 mm port site, the PBI pressure decreased to 9-11 mmHg, whereas the SI1 and SI2 lost insufflation pressures completely. The PBI maintained pressure of >11 mmHg during continuous suction while the SI1 and SI2 lost pressure entirely, and actually showed negative pressure from air suction into the rigid box system. When evaluated statistically with the mixed model repeated measures ANOVA, the SI1 and SI2 performed similarly while the PBI maintained increased pressure. In the experimental rigid box system, the PBI more successfully maintained pressure in response to leakage and suction than SIs.

  11. Cost of radon-barrier systems for uranium mill tailings

    SciTech Connect

    Baker, E.G.; Hartley, J.N.

    1982-08-01

    This report deals specifically with the cost of three types of radon barrier systems, earthen covers, asphalt emulsion covers, and multilayer covers, which could meet standards proposed by the Environmental Protection Agency to stabilize uranium mill tailings located primarily in the western US. In addition, the report includes a sensitivity analysis of various factors which significantly effect the overall cost of the three systems. These analyses were based on a generic disposal site. Four different 3m thick earthen covers were tested and cost an average of $27/m/sup 2/. The least expensive earthen cover cost was about $21/m/sup 2/. The asphalt cover system (6 to 7 cm of asphalt topped with 0.6m of overburden) cost about $28/m/sup 2/. The four multilayer covers averaged $57/m/sup 2/, but materials handling problems encountered during the test inflated this cost above what was anticipated and significant cost reductions should be possible. The least expensive multilayer cover cost $43/m/sup 2/. Based on the results of the Grand Junction field test we estimated the cost of covering the tailings from three high priority sites, Durango, Shiprock, and Salt Lake City (Vitro). The cost of a 3m earthen cover ranged from $18 to 33/m/sup 2/ for the seven disposal sites (two or three at each location) studied. The cost of asphalt cover systems were $23 to 28/m/sup 2/ and the multilayer cover costs were between $31 to 36/m/sup 2/. The earthen cover costs are less than the Grand Junction field test cost primarily because cover material is available at or near most of the disposal sites selected. Earthen material was imported from 6 to 10 miles for the field test. Assuming more efficienct utilization of materials significantly reduced the cost of the multilayer covers.

  12. Benefits, barriers, and limitations on the use of Hospital Incident Command System.

    PubMed

    Shooshtari, Shahin; Tofighi, Shahram; Abbasi, Shirin

    2017-01-01

    Hospital Incident Command System (HICS) has been established with the mission of prevention, response, and recovery in hazards. Regarding the key role of hospitals in medical management of events, the present study is aimed at investigating benefits, barriers, and limitations of applying HICS in hospital. Employing a review study, articles related to the aforementioned subject published from 1995 to 2016 were extracted from accredited websites and databases such as PubMed, Google Scholar, Elsevier, and SID by searching keywords such as HICS, benefits, barriers, and limitations. Then, those articles were summarized and reported. Using of HICS can cause creating preparedness in facing disasters, constructive management in strategies of controlling events, and disasters. Therefore, experiences indicate that there are some limitations in the system such as failure to assess the strength and severity of vulnerabilities of hospital, no observation of standards for disaster management in the design, constructing and equipping hospitals, and the absence of a model for evaluating the system. Accordingly, the conducted studies were investigated for probing the performance HICS. With regard to the role of health in disaster management, it requires advanced international methods in facing disasters. Using accurate models for assessing, the investigation of preparedness of hospitals in precrisis conditions based on components such as command, communications, security, safety, development of action plans, changes in staff's attitudes through effective operational training and exercises and creation of required maneuvers seems necessary.

  13. Psychometric assessment of the Adolescent Physical Activity Perceived Benefits and Barriers Scales.

    PubMed

    Robbins, Lorraine B; Wu, Tsu-Yin; Sikorskii, Alla; Morley, Blair

    2008-01-01

    The purpose of this study was to psychometrically test the Adolescent Physical Activity Perceived Benefits and Barriers Scales developed for middle-school-age youth. A total of 206 racially diverse 6th, 7th, and 8th graders completed questionnaires at two time points (2 weeks apart). For the 10-item Perceived Benefits Scale and the 9-item Perceived Barriers Scale, test-retest reliability (r = .70; r = .71, respectively) and internal consistency (Cronbach's alpha was .80 and .79, respectively, at time 1) were supported. Principal components analysis with Varimax rotation was employed to assess construct validity. A 2-factor solution emerged for each scale as predicted. The relationship between both scale scores and self-reported physical activity provided additional evidence of validity. Both instruments were found to be reliable and valid for measuring the perceived benefits of and barriers to physical activity in middle school youth.

  14. Understanding the THMC evolution of bentonite barrier — modeling an in situ test for bentonite backfilled engineered barrier system

    NASA Astrophysics Data System (ADS)

    Zheng, L.; Xu, H.; Rutqvist, J.; Birkholzer, J. T.

    2016-12-01

    The most common buffer material for engineered barrier system (EBS) is compacted bentonite, which features low permeability and high retardation of radionuclide transport. The safety functions of EBS bentonite include limiting transport in the near field; damping the shear movement of the host rock; preventing the sinking of canisters, limiting pressure on the canister and rock, and reducing microbial activity. To assess whether EBS bentonite can maintain these favorable features when undergoing heating from the waste package and hydration from the host rock, we need a thorough understanding of the thermal, hydrological, mechanical, and chemical evolution of bentonite under disposal conditions. The FEBEX (Full-scale Engineered Barrier EXperiment) in situ test was dismantled after 18 years' heating and hydration. The comprehensive THMC data obtained in the test provide a unique opportunity to validate coupled THMC models and deepen our understanding of the THMC evolution in bentonite. In this presentation, coupled THMC models were developed for the in situ test. Water content data obtained after dismantling and relative humidity data measured real time showed that the hydration of bentonite is slower than predicted by the typical Darcy flow model. Including Non-Darcian flow into the model however leads a significant underestimation of the relative humidity data. The reason could be that the calibration of relative permeability (and retention curve) already encompasses the nonlinear relationship between gradient and flux for bentonite, which would obviate the consideration of Non-Darcian flow in the model. THMC models that take into account the porosity and permeability changes due to mechanical processes match reasonably well all the THM data. However, they did not provide a desirable fit of the measured Cl concentration profile, further calibration of porosity/permeability changes over the course of hydration and swelling and considering thermal osmosis eventually

  15. Zebrafish as a visual and dynamic model to study the transport of nanosized drug delivery systems across the biological barriers.

    PubMed

    Li, Ye; Miao, Xiaoqing; Chen, Tongkai; Yi, Xiang; Wang, Ruibing; Zhao, Haitao; Lee, Simon Ming-Yuen; Wang, Xueqing; Zheng, Ying

    2017-08-01

    With the wide application of nanotechnology to drug delivery systems, a simple, dynamic and visual in vivo model for high-throughput screening of novel formulations with fluorescence markers across biological barriers is desperately needed. In vitro cell culture models have been widely used, although they are far from a complimentary in vivo system. Mammalian animal models are common predictive models to study transport, but they are costly and time consuming. Zebrafish (Danio rerio), a small vertebrate model, have the potential to be developed as an "intermediate" model for quick evaluations. Based on our previously established coumarin 6 nanocrystals (C6-NCs), which have two different sizes, the present study investigates the transportation of C6-NCs across four biological barriers, including the chorion, blood brain barrier (BBB), blood retinal barrier (BRB) and gastrointestinal (GI) barrier, using zebrafish embryos and larvae as in vivo models. The biodistribution and elimination of C6 from different organs were quantified in adult zebrafish. The results showed that compared to 200nm C6-NCs, 70nm C6-NCs showed better permeability across these biological barriers. A FRET study suggested that intact C6-NCs together with the free dissolved form of C6 were absorbed into the larval zebrafish. More C6 was accumulated in different organs after incubation with small sized NCs via lipid raft-mediated endocytosis in adult zebrafish, which is consistent with the findings from in vitro cell monolayers and the zebrafish larvae model. C6-NCs could be gradually eliminated in each organ over time. This study demonstrated the successful application of zebrafish as a simple and dynamic model to simultaneously assess the transport of nanosized drug delivery systems across several biological barriers and biodistribution in different organs, especially in the brain, which could be used for central nervous system (CNS) drug and delivery system screening. Copyright © 2017 Elsevier B

  16. Engineered Barrier Systems Thermal-Hydraulic-Chemical Column Test Report

    SciTech Connect

    W.E. Lowry

    2001-12-13

    The Engineered Barrier System (EBS) Thermal-Hydraulic-Chemical (THC) Column Tests provide data needed for model validation. The EBS Degradation, Flow, and Transport Process Modeling Report (PMR) will be based on supporting models for in-drift THC coupled processes, and the in-drift physical and chemical environment. These models describe the complex chemical interaction of EBS materials, including granular materials, with the thermal and hydrologic conditions that will be present in the repository emplacement drifts. Of particular interest are the coupled processes that result in mineral and salt dissolution/precipitation in the EBS environment. Test data are needed for thermal, hydrologic, and geochemical model validation and to support selection of introduced materials (CRWMS M&O 1999c). These column tests evaluated granular crushed tuff as potential invert ballast or backfill material, under accelerated thermal and hydrologic environments. The objectives of the THC column testing are to: (1) Characterize THC coupled processes that could affect performance of EBS components, particularly the magnitude of permeability reduction (increases or decreases), the nature of minerals produced, and chemical fractionation (i.e., concentrative separation of salts and minerals due to boiling-point elevation). (2) Generate data for validating THC predictive models that will support the EBS Degradation, Flow, and Transport PMR, Rev. 01.

  17. Evaluation of thermal barrier coating systems on novel substrates

    NASA Astrophysics Data System (ADS)

    Pint, B. A.; Wright, I. G.; Brindley, W. J.

    2000-06-01

    Testing was conducted on both plasma-sprayed (PS) and electron beam-physical vapor deposited (EB-PVD) Y2O3-stabilized ZrO2 (YSZ) thermal barrier coatings (TBCs) applied directly to oxidation-resistant substrates such as β-NiAl, oxide-dispersed FeCrAl, and NiCr. On an alloy that forms a very adherent alumina scale, β-NiAl+Zr, the coating lifetime of YSZ in furnace cyclic tests was 6 or more times longer than on state-of-the-art, YSZ coatings on single-crystal Ni-base superalloys with MCrAlY or Pt aluminide bond coats. Coatings on FeCrAl alloys appear to be a viable option for applications such as the external skin of the X-33, single stage to orbit, reusable launch vehicle. Model chromia-forming bond coat compositions also show promise for power generation applications at temperatures where hot corrosion may be a major problem. In general, while this work examined unique materials systems, many of the same fundamental failure mechanisms observed in conventional TBCs were observed.

  18. Numerical heat transfer attic model using a radiant barrier system

    SciTech Connect

    Moujaes, S.F.; Alsaiegh, N.T.

    2000-04-01

    A two-dimensional, steady-state finite-element model was developed to simulate the thermal effects of the application of an attic radiant barrier system (ARBS) inside a ventilated residential attic. The attic is ventilated using the exhaust air from an evaporative cooler. The study uses a {kappa}-{epsilon} turbulent model to describe the velocity and temperature distributions in the attic. The ambient temperature and solar isolation densities on the outside inclined attic surfaces are used as driving functions for the model. The model also included the appropriate heat exchange modes of convection and radiation on these outside surfaces. Several recirculation zones were visually observed in the attic flow pattern. Also, the use of the ARBS seems to lower the heat transfer through the ceiling by 25--30%, but this effect decreases significantly as the outside ventilation rates are increased through the attic space. The 2D model revealed some interesting temperature distributions along the attic surfaces that could not have been predicted by the one-dimensional models. The lower emissivity ARBS seems to raise the temperature of the inclined attic surfaces as well as the temperature of the exhausted ventilation air.

  19. MERCURY OXIDIZATION IN NON-THERMAL PLASMA BARRIER DISCHARGE SYSTEM

    SciTech Connect

    V.K. Mathur

    2003-02-01

    In the past decade, the emission of toxic elements from human activities has become a matter of great public concern. Hg, As, Se and Cd typically volatilize during a combustion process and are not easily caught with conventional air pollution control techniques. In addition, there is no pollution prevention technique available now or likely be available in the foreseeable future that can prevent the emission of these trace elements. These trace elements pose additional scientific challenge as they are present at only ppb levels in large gas streams. Mercury, in particular, has attracted significant attention due to its high volatility, toxicity and potential threat to human health. In the present research work, a non-thermal plasma dielectric barrier discharge technique has been used to oxidize Hg{sup 0}(g) to HgO. The basic premise of this approach is that Hg{sup 0} in vapor form cannot be easily removed in an absorption tower whereas HgO as a particulate is amiable to water scrubbing. The work presented in this report consists of three steps: (1) setting-up of an experimental apparatus to generate mercury vapors at a constant rate and modifying the existing non-thermal plasma reactor system, (2) solving the analytical challenge for measuring mercury vapor concentration at ppb level, and (3) conducting experiments on mercury oxidation under plasma conditions to establish proof of concept.

  20. ARCTIC FOUNDATIONS, INC. FREEZE BARRIER SYSTEM - SITE TECHNOLOGY CAPSULE

    EPA Science Inventory

    Arctic Foundations, Inc. (AFI), of Anchorage, Alaska has developed a freeze barrier technology designed to prevent the migration of contaminants in groundwater by completely isolating contaminant source areas until appropriate remediation techniques can be applied. With this tec...

  1. ARCTIC FOUNDATIONS, INC. FREEZE BARRIER SYSTEM - SITE TECHNOLOGY CAPSULE

    EPA Science Inventory

    Arctic Foundations, Inc. (AFI), of Anchorage, Alaska has developed a freeze barrier technology designed to prevent the migration of contaminants in groundwater by completely isolating contaminant source areas until appropriate remediation techniques can be applied. With this tec...

  2. Motivations and barriers to implementing electronic health records and ED information systems in Japan.

    PubMed

    Inokuchi, Ryota; Sato, Hajime; Nakamura, Kensuke; Aoki, Yuta; Shinohara, Kazuaki; Gunshin, Masataka; Matsubara, Takehiro; Kitsuta, Yoichi; Yahagi, Naoki; Nakajima, Susumu

    2014-07-01

    Although electronic health record systems (EHRs) and emergency department information systems (EDISs) enable safe, efficient, and high-quality care, these systems have not yet been studied well. Here, we assessed (1) the prevalence of EHRs and EDISs, (2) changes in efficiency in emergency medical practices after introducing EHR and EDIS, and (3) barriers to and expectations from the EHR-EDIS transition in EDs of medical facilities with EHRs in Japan. A survey regarding EHR (basic or comprehensive) and EDIS implementation was mailed to 466 hospitals. We examined the efficiency after EHR implementation and perceived barriers and expectations regarding the use of EDIS with existing EHRs. The survey was completed anonymously. Totally, 215 hospitals completed the survey (response rate, 46.1%), of which, 76.3% had basic EHRs, 4.2% had comprehensive EHRs, and 1.9% had EDISs. After introducing EHRs and EDISs, a reduction in the time required to access previous patient information and share patient information was noted, but no change was observed in the time required to produce medical records and the overall time for each medical care. For hospitals with EHRs, the most commonly cited barriers to EDIS implementation were inadequate funding for adoption and maintenance and potential adverse effects on workflow. The most desired function in the EHR-EDIS transition was establishing appropriate clinical guidelines for residents within their system. To attract EDs to EDIS from EHR, systems focusing on decreasing the time required to produce medical records and establishing appropriate clinical guidelines for residents are required. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Interdisciplinary barriers: An impediment to the effective application of systems engineering

    NASA Technical Reports Server (NTRS)

    Harrison, E., Jr.

    1971-01-01

    Interdisciplinary transfer of information and technology does not occur very readily, even for system planners, because of the existence of some very real barriers. These barriers to flow of information and technology between disciplines represent one of the important difficulties associated with the application of systems analysis to many problems. The nature and characteristics of some of these barriers are enumerated and discussed in detail. A number of methodologies and techniques which have been specifically developed to aid in the transfer of technology and information across these interdisciplinary barriers is examined.

  4. The Effects of information barrier requirements on the trilateral initiative attribute measurement system (AVNG).

    SciTech Connect

    MacArthur, D. W.; Langner, D. C.; Whiteson, R.; Wolford, J. K.

    2001-01-01

    Although the detection techniques used for measuring classified materials are very similar to those used in unclassified measurements, the surrounding packaging is generally very different. If iZ classified item is to be measured, an information barrier is required to protect any classified data acquired. This information barrier must protect the classified information while giving the inspector confidence that the unclassified outputs accurately reflect the classified inputs, Both information barrier and authentication considerations must be considered during all phases of system design and fabrication. One example of such a measurement system is the attribute measurement system (termed the AVNG) designed for the: Trilateral Initiative. We will discuss the integration of information barrier components into this system as well as the effects of an information barrier (including authentication) concerns on the implementation of the detector systems.

  5. A Temporal Assessment of Barrier Island Vulnerability to Extreme Wave Events, Virginia Coast Reserve

    NASA Astrophysics Data System (ADS)

    Oster, D. J.; Moore, L. J.; Doran, K. J.; Stockdon, H. F.

    2010-12-01

    Barrier island vulnerability to storm-generated waves is directly related to interactions between shoreface morphology and surf-zone dynamics. During storms, the seaward-most dune often limits the landward extent of wave energy; however, if maximum wave run-up exceeds the elevation of the top of the dune, overwash or inundation may occur. The ‘Storm Impact Scale’ presented by Sallenger (2000) classifies barrier beach vulnerability to individual storm events based on the elevation of the frontal dune crest and toe relative to maximum wave run-up. Changes to the dune and beachface can occur over a range of time scales, altering local vulnerability to extreme waves from storms, even as a storm is occurring. As sea level continues to rise, barrier beaches will become increasingly vulnerable to overwash and inundation from a greater number of storms. Our objective is to assess temporal trends in barrier island vulnerability while also exploring island-chain-wide response and recovery from two notably different storm events (Nor’Ida and Hurricane Bonnie) along the undeveloped barrier islands of the Virginia Coast Reserve (VCR). We compare shoreline position and elevations of the frontal dune crest (DHIGH) and dune toe (DLOW) across four lidar data sets collected between 1998-2010. Observed significant wave height and period from the National Data Buoy Center and the Duck, NC Field Research Facility for the time period between 1985 and 2009 are classified to represent one-year, five-year, and ten-year storm events that serve as the basis for comparison of island vulnerability through time to a range of storm severity. Initial results reveal significant spatial and temporal variation in barrier island vulnerability to storms throughout the VCR. Despite the range of variability, all three beach features (i.e., shoreline position, DHIGH and DLOW), have moved landward indicating large-scale, widespread migration, or narrowing, of VCR barrier island landforms over the

  6. Safety assessment of discharge chute isolation barrier preparation and installation activities. Revision 3

    SciTech Connect

    Meichle, R.H.

    1994-11-08

    This revision adds a section addressing impacts of dropping surfacing tool and rack cutter on the basin floor, and corrects typographical errors. The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparisons of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions was made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classifications.

  7. Safety assessment of discharge chute isolation barrier preparation and installation. Revision 1

    SciTech Connect

    Meichle, R.H.

    1994-10-10

    This revision responds to RL comments and increases the discussion of the ``effective hazard categorization`` and the readiness review basis. The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparison of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions were made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classification.

  8. Development and psychometric properties of a survey to assess barriers to implementing advance care planning in primary care.

    PubMed

    Howard, Michelle; Day, Andrew G; Bernard, Carrie; Tan, Amy; You, John; Klein, Doug; Heyland, Daren K

    2017-08-09

    Valid and reliable measurement of barriers to advance care planning (ACP) in health care settings can inform the design of robust interventions. This paper describes the development and psychometric evaluation of an instrument to measure the presence and magnitude of perceived barriers to ACP discussion with patients from the perspective of family physicians. A questionnaire was designed through literature review and expert input, asking family physicians to rate the importance of barriers (0=not at all a barrier, 6=an extreme amount) to ACP discussions with patients, and administered to 117 physicians. Floor effects and missing data patterns were examined. Item-by-item correlations were examined using Pearson correlation. Exploratory factor analysis was conducted (iterated principle factor analysis with oblique rotation), internal consistency (Cronbach's alpha) overall and within factors was calculated and construct validity was evaluated by calculating three correlations with related questions that were specified a priori. The questionnaire included 31 questions in three domains relating to: the clinician, the patient/family and the system or external factors. No items were removed due to missing data, floor effects or high correlation with another item. A solution of three factors accounted for 71% of variance. One item was removed because it did not load strongly on any factor. All other items except one remained in the original domain in the questionnaire. Cronbach's alpha for the three factors ranged from 0.84-0.90. Two of three a priori correlations with related questions were statistically significant. This questionnaire to assess barriers to ACP discussion from the perspective of family physicians demonstrates preliminary evidence of reliability and validity. Copyright © 2017. Published by Elsevier Inc.

  9. System Assessment Standards: Defining the Market for Industrial Energy Assessments

    SciTech Connect

    Sheaffer, Paul; McKane, Aimee; Tutterow, Vestal; Crane, Ryan

    2009-08-01

    Improved efficiency of industrial systems (e.g., compressed air or steam) contributes to a manufacturing facility?s bottom line, improves reliability, and better utilizes assets. Despite these advantages, many industrial facilities continue to have unrealized system optimization potential. A barrier to realizing this potential is the lack of market definition for system energy efficiency assessment services, creating problems for both service providers in establishing market value for their services and for consumers in determining the relative quality of these system assessment services. On August 19, 2008, the American Society of Mechanical Engineers (ASME) issued four new draft Standards for trial use that are designed to raise the bar and define the market for these services. These draft Standards set the requirements for conducting an energy assessment at an industrial facility for four different system types: compressed air, process heating, pumping, and steam. The Standards address topics such as organizing and conducting assessments; analyzing the data collected; and reporting and documentation. This paper addresses both the issues and challenges in developing the Standards and the accompanying Guidance Documents, as well as the result of field testing by industrial facilities, consultants, and utilities during the trial use period that ended in January, 2009. These Standards will be revised and released by ASME for public review, and subsequently submitted for approval as American National Standards for publication in late 2009. Plans for a related activity to establish a professional-level program to certify practitioners in the area of system assessments, opportunities to integrate the ASME Standards with related work on industrial energy efficiency, as well as plans to expand the system assessment Standard portfolio are also discussed.

  10. Fusion of the {sup 9}Be+{sup 144}Sm System at Near Barrier Energies

    SciTech Connect

    Paes, B.; Gomes, P. R. S.; Lubian, J.; Nunes, V.; Canto, L. F.

    2010-08-04

    We analyze the data for complete fusion of the {sup 9}Be+{sup 144}Sm system at near barrier energies by performing coupled channel calculations using a double-folding potential as the bare potential. We use a recently proposed new method of analysis by the introduction of dimensionless fusion functions. We observe enhancement of the fusion cross section at energies below the Coulomb barrier and suppression above the barrier.

  11. Magnetic Resonance Imaging to Assess Blood–Brain Barrier Damage in Murine Trypanosomiasis

    PubMed Central

    Rodgers, Jean; McCabe, Christopher; Gettinby, George; Bradley, Barbara; Condon, Barrie; Kennedy, Peter G. E.

    2011-01-01

    The ability of trypanosomes to invade the brain and induce an inflammatory reaction is well-recognized. This study uses magnetic resonance imaging (MRI) in conjunction with a murine model of central nervous system (CNS) stage trypanosomiasis to investigate this phenomenon at the level of the blood–brain barrier (BBB). Mice were scanned before and after administration of the contrast agent. Signal enhancement maps were generated, and the percentage signal change was calculated. The severity of the neuroinflammation was also assessed. Statistical analysis of the signal change data revealed a significantly (P = 0.028) higher signal enhancement in mice at 28 days post-infection (least squares mean = 26.709) compared with uninfected animals (6.298), indicating the presence of BBB impairment. Leukocytes were found in the meninges and perivascular space of some blood vessels in the infected mice. This study shows that the integrity of the BBB is compromised during CNS stage trypanosomiasis and that the impairment does not correlate with inflammatory cell infiltration. PMID:21292912

  12. Morphology and stratigraphy of small barrier-lagoon systems in Maine

    USGS Publications Warehouse

    Duffy, W.; Belknap, D.F.; Kelley, J.T.

    1989-01-01

    The coast of Maine contains over 200 individual barrier-lagoon systems, most quite small, with an aggregate length of nearly 100 km. Although they represent less than 5% of the tidally influenced coastline of Maine, they are widely distributed and occur in a variety of dynamic regimes and physiographic regions. Their morphology and backbarrier stratigraphy are different from better studied coastal plain systems, and provide important clues to the Holocene evolution of the Maine coast. In a study of geomorphic form and backbarrier stratigraphy, inlet processes and Holocene sea-level rise have been identified as the principal controls on coarse-grained barrier stratigraphy. Barriers in Maine are found in five distinct geomorphic forms, identified herein as: barrier spits, pocket barriers, double tombolos, cuspate barriers and looped barriers. The few long sandy beaches in southwestern Maine are mostly barrier spits. The remainder of the barrier types is composed primarily of gravel or mixed sand and gravel. The barriers protect a variety of backbarrier environments: fresh and brackish ponds, lagoons and fresh- and saltwater marshes. The barriers may or may not have inlets. Normal wave action, coarse-grain size and a deeply embayed coast result in barriers with steep, reflective profiles several meters above MHW. Occasional storm events completely wash over the barriers, building steep, lobate gravel fans along their landward margin. Few, if any, extensive storm layers are recognized as extending into the distal backbarrier environments, however. During sea-level rise and landward barrier retreat, this abrupt, storm-generated transition zone inters the backbarrier sediments. Statistical comparisons of barrier morphology, location and backbarrier environment type with backbarrier stratigraphy show that Holocene backbarrier stratigraphy is best predicted by the modern backbarrier environment type. This, in turn, is influenced most by the absence or presence, and long

  13. A Community-Level Assessment of Barriers to Preventive Health Behaviors Among Culturally Diverse Men.

    PubMed

    Davis, Jenna L; Rivers, Brian M; Rivers, Desiree; Tucker, Carolyn M; Desmond, Frederic F; Arthur, Tya M; Wippold, Guillermo M; Green, B Lee

    2016-11-01

    There are significant gender disparities in health outcomes and health care utilization in the United States, with men experiencing more of these disparities. It is critical to ascertain the interplay between societal conditions, health behaviors, and access to services and the impact of these factors on health outcomes and utilization of health care. The present study is part of a larger initiative titled, The Men's Health Study: Addressing Healthy Lifestyle Behaviors, which has two purposes-to annually assess the motivators of and barriers to health-promoting behaviors among culturally diverse men attending the Men's Health Forum (MHF) and to use this information to develop an intervention program that facilitates healthy lifestyle behaviors among men. The MHF is a community-driven initiative for medically underserved men in Tampa, Florida that offers free health screenings and wellness exhibitors in order to empower men to lead a healthy lifestyle. The purpose of this article is to identify barriers to engaging in health-smart behaviors (e.g., cancer screenings, physical activity) among culturally diverse men who participated in the MHF and to detect any demographic differences among these barriers. A total of 254 men participated in the study. Findings identify that age was the only demographic variable that had a statistically significant association with any of the cancer-screening barriers. Some cancer-screening barriers appear to exist among all demographic groups since no statistical demographic differences were discovered. Income and education were significantly associated with barriers to engaging in health-smart behaviors. This may give researchers, health educators, and providers information needed to customize interventions to promote health and preventive health care among culturally diverse men.

  14. Design of noise barrier inspection system for high-speed railway

    NASA Astrophysics Data System (ADS)

    Liu, Bingqian; Shao, Shuangyun; Feng, Qibo; Ma, Le; Cholryong, Kim

    2016-10-01

    The damage of noise barriers will highly reduce the transportation safety of the high-speed railway. In this paper, an online inspection system of noise barrier based on laser vision for the safety of high-speed railway is proposed. The inspection system, mainly consisted of a fast camera and a line laser, installed in the first carriage of the high-speed CIT(Composited Inspection Train).A Laser line was projected on the surface of the noise barriers and the images of the light line were received by the camera while the train is running at high speed. The distance between the inspection system and the noise barrier can be obtained based on laser triangulation principle. The results of field tests show that the proposed system can meet the need of high speed and high accuracy to get the contour distortion of the noise barriers.

  15. Advanced thermal barrier coating system development. Technical progress report, January 1, 1996--March 31, 1996

    SciTech Connect

    1996-04-08

    Objectives of this program are to provide a thermal barrier coating system with increased temperature capability and improved reliability relative to current state of the art systems. This report describes the bond coat deposition process, manufacturing, and repair.

  16. Advanced thermal barrier coating system development. Technical progress report, April 1, 1996--May 31, 1996

    SciTech Connect

    1996-06-10

    Objectives of this program are to provide an improved thermal barrier system with increased temperature capability and reliability relative to current systems. This report describes the bond coat development and deposition, manufacturing, and repair.

  17. Identification of Barriers to Munitions Detection Technology Transfer: Unexploded Ordnance Wide Area Assessment

    DTIC Science & Technology

    2008-09-01

    Noblis Technical Report Identification of Barriers to Munitions Detection Technology Transfer Unexploded Ordnance Wide Area Assessment...September 2008 Jon Horin Robert S. Wassmann Customer: SERDP/ESTCP Contract No.: FA8903-04-D-8715 Noblis Dept. No.: H300 Project No... Noblis ,3150 Fairview Park Drive South,Falls Church,VA,22042-4504 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND

  18. Listening to rural Hispanic immigrants in the Midwest: a community-based participatory assessment of major barriers to health care access and use.

    PubMed

    Cristancho, Sergio; Garces, D Marcela; Peters, Karen E; Mueller, Benjamin C

    2008-05-01

    Hispanic immigrants are increasingly residing in rural communities, including in the midwestern United States. Limitations in the ability of rural Hispanics to access and utilize health care contribute to patterns of poor health and health disparity. A conceptual model of "vulnerability" guides this community-based participatory assessment project designed to explore rural Hispanics' perceived barriers to accessing and utilizing health care. Findings from a series of 19 focus groups with 181 participants from three communities in the upper Midwest identified perceived barriers at the individual and health care system levels. The most commonly perceived barriers were the lack of and limitations in health insurance coverage, high costs of health care services, communication issues involving patients and providers, legal status/discrimination, and transportation concerns. Findings imply that these barriers could be addressed using multiple educational and health service delivery policy-related strategies that consider the vulnerable nature of this growing population.

  19. System and Patient Barriers to Care among People Living with HIV/AIDS in Houston/Harris County, Texas: HIV Medical Care Providers' Perspectives.

    PubMed

    Mgbere, Osaro; Khuwaja, Salma; Bell, Tanvir K; Rodriguez-Barradas, Maria C; Arafat, Raouf; Essien, Ekere James; Singh, Mamta; Aguilar, Jonathan; Roland, Eric

    2015-01-01

    In the United States, a considerable number of people diagnosed with HIV are not receiving HIV medical care due to some barriers. Using data from the Medical Monitoring Project survey of HIV medical care providers in Houston/Harris County, Texas, we assessed the HIV medical care providers' perspectives of the system and patient barriers to HIV care experienced by people living with HIV/AIDS (PLWHA). The study findings indicate that of the 14 HIV care barriers identified, only 1 system barrier and 7 patient barriers were considered of significant (P ≤ .05) importance, with the proportion of HIV medical care providers' agreement to these barriers ranging from 73.9% (cost of health care) to 100% (lack of social support systems and drug abuse problems). Providers' perception of important system and patient barriers varied significantly (P ≤ .05) by profession, race/ethnicity, and years of experience in HIV care. To improve access to and for consistent engagement in HIV care, effective intervention programs are needed to address the barriers identified especially in the context of the new health care delivery system. © The Author(s) 2014.

  20. Assessing transmissible spongiform encephalopathy species barriers with an in vitro prion protein conversion assay

    USGS Publications Warehouse

    Johnson, Christopher J.; Carlson, Christina M.; Morawski, Aaron R.; Manthei, Alyson; Cashman, Neil R.

    2015-01-01

    Studies to understanding interspecies transmission of transmissible spongiform encephalopathies (TSEs, prion diseases) are challenging in that they typically rely upon lengthy and costly in vivo animal challenge studies. A number of in vitro assays have been developed to aid in measuring prion species barriers, thereby reducing animal use and providing quicker results than animal bioassays. Here, we present the protocol for a rapid in vitroprion conversion assay called the conversion efficiency ratio (CER) assay. In this assay cellular prion protein (PrPC) from an uninfected host brain is denatured at both pH 7.4 and 3.5 to produce two substrates. When the pH 7.4 substrate is incubated with TSE agent, the amount of PrPC that converts to a proteinase K (PK)-resistant state is modulated by the original host’s species barrier to the TSE agent. In contrast, PrPC in the pH 3.5 substrate is misfolded by any TSE agent. By comparing the amount of PK-resistant prion protein in the two substrates, an assessment of the host’s species barrier can be made. We show that the CER assay correctly predicts known prion species barriers of laboratory mice and, as an example, show some preliminary results suggesting that bobcats (Lynx rufus) may be susceptible to white-tailed deer (Odocoileus virginianus) chronic wasting disease agent.

  1. Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In Vitro Prion Protein Conversion Assay

    PubMed Central

    Johnson, Christopher J.; Carlson, Christina M.; Morawski, Aaron R.; Manthei, Alyson; Cashman, Neil R.

    2015-01-01

    Studies to understanding interspecies transmission of transmissible spongiform encephalopathies (TSEs, prion diseases) are challenging in that they typically rely upon lengthy and costly in vivo animal challenge studies. A number of in vitro assays have been developed to aid in measuring prion species barriers, thereby reducing animal use and providing quicker results than animal bioassays. Here, we present the protocol for a rapid in vitro prion conversion assay called the conversion efficiency ratio (CER) assay. In this assay cellular prion protein (PrPC) from an uninfected host brain is denatured at both pH 7.4 and 3.5 to produce two substrates. When the pH 7.4 substrate is incubated with TSE agent, the amount of PrPC that converts to a proteinase K (PK)-resistant state is modulated by the original host’s species barrier to the TSE agent. In contrast, PrPC in the pH 3.5 substrate is misfolded by any TSE agent. By comparing the amount of PK-resistant prion protein in the two substrates, an assessment of the host’s species barrier can be made. We show that the CER assay correctly predicts known prion species barriers of laboratory mice and, as an example, show some preliminary results suggesting that bobcats (Lynx rufus) may be susceptible to white-tailed deer (Odocoileus virginianus) chronic wasting disease agent. PMID:25867521

  2. Glomerular permeability barrier in the rat. Functional assessment by in vitro methods.

    PubMed Central

    Daniels, B S; Deen, W M; Mayer, G; Meyer, T; Hostetter, T H

    1993-01-01

    The formation of glomerular ultrafiltrate is dependent on the prevailing hemodynamic forces within the glomerular microcirculation and the intrinsic properties of the filtration barrier. However, direct assessment of the permeability barrier is difficult with most available techniques. We used confocal microscopy to image 1-micron thick optical cross-sections of isolated intact glomeruli and glomeruli denuded of cells and quantitated dextran (70,000 mol wt) diffusion from the capillary lumen. Dextran permeance was 11 times greater for the acellular filtration barrier than the intact peripheral capillary. Consideration of the basement membrane and cells as series resistors demonstrated that cells of the filtration barrier contribute 90% of the total resistance to macromolecular permeance. Using a different approach, dextran sieving coefficients for acellular glomeruli consolidated as a multilayer sheet in a filtration cell were similar to those for intact glomeruli in vivo at radii 30-36 A and approximately 50 times greater at a dextran radius of 60 A. The presence of cells significantly reduced hydraulic permeability determined on consolidated intact or acellular glomeruli in an ultrafiltration cell with 50 mmHg applied pressure. The glomerular basement membrane does restrict macromolecular permeability but cells are important determinants of the overall macromolecular and hydraulic permeability of the glomerulus. Images PMID:7688767

  3. Assessing transmissible spongiform encephalopathy species barriers with an in vitro prion protein conversion assay.

    PubMed

    Johnson, Christopher J; Carlson, Christina M; Morawski, Aaron R; Manthei, Alyson; Cashman, Neil R

    2015-03-10

    Studies to understanding interspecies transmission of transmissible spongiform encephalopathies (TSEs, prion diseases) are challenging in that they typically rely upon lengthy and costly in vivo animal challenge studies. A number of in vitro assays have been developed to aid in measuring prion species barriers, thereby reducing animal use and providing quicker results than animal bioassays. Here, we present the protocol for a rapid in vitro prion conversion assay called the conversion efficiency ratio (CER) assay. In this assay cellular prion protein (PrPC) from an uninfected host brain is denatured at both pH 7.4 and 3.5 to produce two substrates. When the pH 7.4 substrate is incubated with TSE agent, the amount of PrPC that converts to a proteinase K (PK)-resistant state is modulated by the original host's species barrier to the TSE agent. In contrast, PrPC in the pH 3.5 substrate is misfolded by any TSE agent. By comparing the amount of PK-resistant prion protein in the two substrates, an assessment of the host's species barrier can be made. We show that the CER assay correctly predicts known prion species barriers of laboratory mice and, as an example, show some preliminary results suggesting that bobcats (Lynx rufus) may be susceptible to white-tailed deer (Odocoileus virginianus) chronic wasting disease agent.

  4. Oxidation and degradation of thermal barrier coating systems

    NASA Astrophysics Data System (ADS)

    Haynes, James Allen

    Thermal barrier coatings (TBCs), which consist of an oxidation-resistant metallic bond coating overlaid with a thermally-insulating Ysb2Osb3-stabilized ZrOsb2 (YSZ) top coating, are used to protect superalloy hardware in gas turbine engines. Spallation of the YSZ is accelerated by growth of an interfacial Alsb2Osb3 scale at high temperatures. The mechanisms of oxidation-related degradation are not well understood for air plasma-sprayed (APS) TBCs, whereas Alsb2Osb3 thermomechanical failure is the dominant degradation mode in electron beam-physical vapor deposition (EB-PVD) TBCs. This work investigated the isothermal oxidation and thermocyclic degradation of various TBC systems; with particular emphasis on the growth kinetics, microstructures, flaw content, fracture behavior and micro-mechanical properties of the Alsb2Osb3 interfacial scales. The isothermal oxidation kinetics of plasma-sprayed NiCrAlY were not influenced by the presence of an APS YSZ top coating (at 1150sp°C). However, the isothermal oxidation rate constants of NiCoCrAlY bond coatings were accelerated by a factor of 2 (at 950, 1050 and 1150sp°C) when overlaid with a commercial EB-PVD TBC. Thermocyclic failure of APS TBCs occurred by progressive YSZ fracture and crack link-up. Severe fracture and buckling of the interfacial Alsb2Osb3 during thermal cycling did not induce rapid failure of APS TBCs. Evaluation of the interfacial Alsb2Osb3 scale microstructures (on APS TBCs) after thermal cycling revealed the following: thermocyclic damage occurred by both oxide-metal delamination and by internal fracture; Alsb2Osb3 scale crack healing by sintering occurred at 1150sp°C; surfaces with a sharp radius of curvature induced less Alsb2Osb3 damage than gradually convex surfaces; scale grain boundary void growth was accelerated by thermal cycling; and higher void contents were observed in scales which formed on convex surfaces. There were no significant changes in the hardness or Young's modulus of the Alsb2

  5. Assessing advantages and barriers to telemedicine adoption in the practice setting: A MyCareTeam(TM) exemplar.

    PubMed

    L'Esperance, Shaun T; Perry, Donna J

    2016-06-01

    Telemedicine is an evolving field that holds great potential to improve patient outcomes. The National Organization of Nurse Practitioner Faculties core competencies now require all nurse practitioners (NPs) to be competent utilizing telemedicine to address various patient and healthcare system needs. While telemedicine offers advantages to patient care, adoption of new technologies can be challenging. An assessment of perceived advantages and barriers to MyCareTeam, an online diabetes management system, was conducted at an adult diabetes clinic. Two survey questionnaires were developed based on the Diffusion of Innovations (DOI) theory. The surveys were administered to patients in the clinic waiting room and sent to all clinical staff via an e-mail link. The findings of this project suggested a novel way to classify patients with regard to their use of the technology with implications for practice. Recommendations include outreach to enhance knowledge and awareness of MyCareTeam, reinforcing the full scope of the system, and improved technical support. DOI theory is a framework that may be utilized by NPs as a tool for assessing advantages and barriers to telemedicine applications in the practice setting in order to identify strategies to promote adoption and use. ©2015 American Association of Nurse Practitioners.

  6. Rheumatologists' perception of systemic lupus erythematosus quality indicators: significant interest and perceived barriers.

    PubMed

    Casey, Carolyn; Chung, Cecilia P; Crofford, Leslie J; Barnado, April

    2017-01-01

    Differences in quality of care may contribute to health disparities in systemic lupus erythematosus (SLE). Studies show low physician adherence rates to the SLE quality indicators but do not assess physician perception of SLE quality indicators or quality improvement. Using a cross-sectional survey of rheumatologists in the southeastern USA, we assessed the perception and involvement of rheumatologists in quality improvement and the SLE quality indicators. Using electronic mail, an online survey of 32 questions was delivered to 568 rheumatologists. With a response rate of 19% (n = 106), the majority of participants were male, Caucasian, with over 20 years of experience, and seeing adult patients in an academic setting. Participants had a positive perception toward quality improvement (81%) with a majority responding that the SLE quality indicators would significantly impact quality of care (54%). While 66% of respondents were familiar with the SLE quality indicators, only 18% of respondents reported using them in everyday practice. The most commonly reported barrier to involvement in quality improvement and the SLE quality indicators was time. Rheumatologists had a positive perception of the SLE quality indicators and agreed that use of the quality indicators could improve quality of care in SLE; however, they identified time as a barrier to implementation. Future studies should investigate methods to increase use of the SLE quality indicators.

  7. A suction blister model reliably assesses skin barrier restoration and immune response.

    PubMed

    Smith, Tracey J; Wilson, Marques A; Young, Andrew J; Montain, Scott J

    2015-02-01

    Skin wound healing models can be used to detect changes in immune function in response to interventions. This study used a test-retest format to assess the reliability of a skin suction blister procedure for quantitatively evaluating human immune function in repeated measures type studies. Up to eight suction blisters (~30 mm(2)) were induced via suction on each participant's left and right forearm (randomized order; blister session 1 and 2), separated by approximately one week. Fluid was sampled from each blister, and the top layer of each blister was removed to reveal up to eight skin wounds. Fluid from each wound was collected 4, 7 and 24h after blisters were induced, and proinflammatory cytokines were measured. Transepidermal water loss (TEWL), to assess skin barrier recovery, was measured daily at each wound site until values were within 90% of baseline values (i.e., unbroken skin). Sleep, stress and inflammation (i.e., factors that affect wound healing and immune function), preceding the blister induction, were assessed via activity monitors (Actical, Philips Respironics, Murrysville, Pennsylvania), the Perceived Stress Scale (PSS) and C-reactive protein (CRP), respectively. Area-under-the-curve and TEWL, between blister session 1 and 2, were compared using Pearson correlations and partial correlations (controlling for average nightly sleep, PSS scores and CRP). The suction blister method was considered reliable for assessing immune response and skin barrier recovery if correlation coefficients reached 0.7. Volunteers (n=16; 12 M; 4F) were 23 ± 5 years [mean ± SD]. Time to skin barrier restoration was 4.9 ± 0.8 and 4.8 ± 0.9 days for sessions 1 and 2, respectively. Correlation coefficients for skin barrier restoration, IL-6, IL-8 and MIP-1α were 0.9 (P<0.0001), 0.7 (P=0.008) and 0.9 (P<0.0001), respectively. When average nightly sleep, PSS scores and CRP (i.e., percent difference between sessions 1 and 2) were taken into consideration, correlations in

  8. Barriers to genuine consumer and carer participation from the perspectives of Australian systemic mental health advocates.

    PubMed

    Gee, Alison; McGarty, Craig; Banfield, Michelle

    2016-06-01

    Consumer and carer participation in mental health service development and evaluation has widespread nominal support. However, genuine and consistent participation remains elusive due to systemic barriers. This paper explores barriers to reform for mental health services from the perspectives of consumers and carers actively engaged in advocating for improvements in the mental health system. Qualitative research with two mental health systemic advocacy organisations analysed 17 strategic communication documents and nine interviews to examine barriers to reform and participation identified by consumer and carer advocates and staff. A number of individual-level barriers were described, however advocates gave more focus to systemic barriers, for which five themes emerged. These reflected lack of awareness, limited participation opportunities, slow progress for change, policy issues and mental health culture including stigma. Findings highlight systemic barriers to participation for consumer and carer advocates as a whole and the influence of these barriers on the individual experiences of those engaged in advocacy and representation work. Participants also emphasised the need for leadership to overcome some of these obstacles and move towards genuine consumer and carer participation and reform. Findings are discussed in the context of power within mental health systems.

  9. Reactive Transport and Coupled THM Processes in Engineering Barrier Systems (EBS)

    SciTech Connect

    Steefel, Carl; Rutqvist, Jonny; Tsang, Chin-Fu; Liu, Hui-Hai; Sonnenthal, Eric; Houseworth, Jim; Birkholzer, Jens

    2010-08-31

    Geological repositories for disposal of high-level nuclear wastes generally rely on a multi-barrier system to isolate radioactive wastes from the biosphere. The multi-barrier system typically consists of a natural barrier system, including repository host rock and its surrounding subsurface environment, and an engineering barrier system (EBS). EBS represents the man-made, engineered materials placed within a repository, including the waste form, waste canisters, buffer materials, backfill and seals (OECD, 2003). EBS plays a significant role in the containment and long-term retardation of radionuclide release. EBS is involved in complex thermal, hydrogeological, mechanical, chemical and biological processes, such as heat release due to radionuclide decay, multiphase flow (including gas release due to canister corrosion), swelling of buffer materials, radionuclide diffusive transport, waste dissolution and chemical reactions. All these processes are related to each other. An in-depth understanding of these coupled processes is critical for the performance assessment (PA) for EBS and the entire repository. Within the EBS group of Used Fuel Disposition (UFD) Campaign, LBNL is currently focused on (1) thermal-hydraulic-mechanical-chemical (THMC) processes in buffer materials (bentonite) and (2) diffusive transport in EBS associated with clay host rock, with a long-term goal to develop a full understanding of (and needed modeling capabilities to simulate) impacts of coupled processes on radionuclide transport in different components of EBS, as well as the interaction between near-field host rock (e.g., clay) and EBS and how they effect radionuclide release. This final report documents the progress that LBNL has made in its focus areas. Specifically, Section 2 summarizes progress on literature review for THMC processes and reactive-diffusive radionuclide transport in bentonite. The literature review provides a picture of the state-of-the-art of the relevant research areas

  10. Geomicrobiological Regeneration of Iron Sulfides in Engineered barrier Systems

    NASA Astrophysics Data System (ADS)

    Vannela, R.; Adriaens, P.; Hayes, K. F.

    2005-12-01

    The reactive capacity of iron sulfide-based permeable reactive barriers (PRB) to complex and co-precipitate heavy metal ions from groundwater will depend on the potential for regeneration of reactive FeS during the expected lifetime of the PRB. FeS reactivity may decrease in a PRB in time as the result of the following processes: (i) oxidation of FeS and the formation of ferric iron (Fe(III)) oxide solids in the presence of oxygenated groundwater at the entrance of the PRB, (ii) oxidation of FeS in the presence of redox active metals like As(V) with the formation of ferric solids, (iii) co-precipitation of heavy metals within the PRB with the reactive FeS leading to the formation of insoluble metal sulfides co-precipitates with the concomitant release of ferrous iron and formation of ferrous (Fe(II) oxide, hydroxide, or carbonate solids, (iv) clogging of the PRB structure due to formation of precipitate products from processes (i) - (iii).. We have demonstrated the formation of triolite in the presence of an oxidized form of hydrous ferric oxide (HFO), various sulfate concentrations, and biomass densities for the sulfate reducing bacterium (SRB) Desulfovibrio vulgaris. This result has allowed us to demonstrate the feasibility of regeneration of FeS from the ferric oxide and hydroxide solids that may be produced under scenarios (i) and (ii) above as well as to establish the electron donor and acceptor requirements for this SRB. Using Desulfobacterium autotrophicum, both HFO and soluble complexed forms of ferric iron gave rise to the formation of mackinawite. The latter have been shown to react with As (V) and Cd (II) to form ferric solids. Both organisms will be used to generate FeS solids in the presence of crystalline forms of ferric solids expected to form from scenarios (i) and (ii) (e.g., goethite and the mixed Fe(II)/(Fe(III) magnetite, and green rusts) and ferrous iron solids from scenarios (iii) and (iv) (Fe(II) oxides and siderite). Similar to the study

  11. Shielded corneosurfametry and corneoxenometry: novel bioassays for the assessment of skin barrier products.

    PubMed

    Goffin, V; Piérard-Franchimont, C; Piérard, G E

    1998-01-01

    One of the most frequent occupational and environmental insults to the skin is linked to chronic exposure to weak irritants. There is a need for new predictive tests assessing the efficacy of barrier creams. Shielded variants of corneosurfametry and corneoxenometry are introduced as novel ex vivo bioassays applicable for comparing protection to surfactants and organic solvents. Both bioassays showed good reproducibility for each offending agent and skin-protective products. Significant differences in efficacy were indicated between the presumptive barrier products. Shielded corneosurfametry and corneoxenometry may be convenient bioassays to compare the protection afforded by topical products against specific offending compounds to the skin. They avoid animal testing and toxicological hazards in human testing. In addition, they are cheap, rapid and reproducible.

  12. Interactions between barrier islands and backbarrier marshes affect island system response to sea level rise: Insights from a coupled model

    NASA Astrophysics Data System (ADS)

    Walters, David; Moore, Laura J.; Duran Vinent, Orencio; Fagherazzi, Sergio; Mariotti, Giulio

    2014-09-01

    Interactions between backbarrier marshes and barrier islands will likely play an important role in determining how low-lying coastal systems respond to sea level rise and changes in storminess in the future. To assess the role of couplings between marshes and barrier islands under changing conditions, we develop and apply a coupled barrier island-marsh model (GEOMBEST+) to assess the impact of overwash deposition on backbarrier marsh morphology and of marsh morphology on rates of island migration. Our model results suggest that backbarrier marsh width is in a constant state of change until either the backbarrier basin becomes completely filled or backbarrier marsh deposits have completely eroded away. Results also suggest that overwash deposition is an important source of sediment, which allows existing narrow marshes to be maintained in a long-lasting alternate state (~500 m wide in the Virginia Barrier Islands) within a range of conditions under which they would otherwise disappear. The existence of a narrow marsh state is supported by observations of backbarrier marshes along the eastern shore of Virginia. Additional results suggest that marshes reduce accommodation in the backbarrier bay, which, in turn, decreases island migration rate. As climate change results in sea level rise, and the increased potential for intense hurricanes resulting in overwash, it is likely that these couplings will become increasingly important in determining future system behavior.

  13. The advantages and barriers in the implementation of a substance dependence treatment information system (SDTIS).

    PubMed

    Ajami, Sima; Mellat-Karkevandi, Zahra

    2015-11-01

    Addiction is a phenomenon that causes structural changes in different systems of society. Studies show for planning of addiction prevention and treatment, it is necessary to create an information management system. Substance dependence information systems refer to systems which collect, analyse and report data related to substance dependence information. The aim of this study was to identify advantages and barriers to implement Substance Dependence Treatment Information System (SDTIS). This study was a narrative review. Our review divided into three phases: literature collection, assessing, and selection. We employed the following keywords and their combinations in different areas of articles. In this study, 22 of collected articles and reports were selected based on their relevancy. We found many advantages for a substance dependence treatment information system such as recording sufficient, complete and accurate information and easy and timely access to them and monitoring and enhancing the quality of care received by patients. But we may face some concerns for implementing this information system like taking time and funds from client services, being expensive or even problems regarding the quality of data contained in these information systems. There are some important problems in the way of implementing. In order to overcome these issues, we need to raise community awareness.

  14. The advantages and barriers in the implementation of a substance dependence treatment information system (SDTIS)

    PubMed Central

    Ajami, Sima; Mellat-Karkevandi, Zahra

    2015-01-01

    Addiction is a phenomenon that causes structural changes in different systems of society. Studies show for planning of addiction prevention and treatment, it is necessary to create an information management system. Substance dependence information systems refer to systems which collect, analyse and report data related to substance dependence information. The aim of this study was to identify advantages and barriers to implement Substance Dependence Treatment Information System (SDTIS). This study was a narrative review. Our review divided into three phases: literature collection, assessing, and selection. We employed the following keywords and their combinations in different areas of articles. In this study, 22 of collected articles and reports were selected based on their relevancy. We found many advantages for a substance dependence treatment information system such as recording sufficient, complete and accurate information and easy and timely access to them and monitoring and enhancing the quality of care received by patients. But we may face some concerns for implementing this information system like taking time and funds from client services, being expensive or even problems regarding the quality of data contained in these information systems. There are some important problems in the way of implementing. In order to overcome these issues, we need to raise community awareness. PMID:26941816

  15. Barriers to the uptake and use of feedback in the context of summative assessment.

    PubMed

    Harrison, Christopher J; Könings, Karen D; Schuwirth, Lambert; Wass, Valerie; van der Vleuten, Cees

    2015-03-01

    Despite calls for feedback to be incorporated in all assessments, a dichotomy exists between formative and summative assessments. When feedback is provided in a summative context, it is not always used effectively by learners. In this study we explored the reasons for this. We conducted individual interviews with 17 students who had recently received web based feedback following a summative assessment. Constant comparative analysis was conducted for recurring themes. The summative assessment culture, with a focus on avoiding failure, was a dominant and negative influence on the use of feedback. Strong emotions were prevalent throughout the period of assessment and feedback, which reinforced the focus on the need to pass, rather than excel. These affective factors were heightened by interactions with others. The influence of prior learning experiences affected expectations about achievement and the need to use feedback. The summative assessment and subsequent feedback appeared disconnected from future clinical workplace learning. Socio-cultural influences and barriers to feedback need to be understood before attempting to provide feedback after all assessments. A move away from the summative assessment culture may be needed in order to maximise the learning potential of assessments.

  16. Theoretical domains framework to assess barriers to change for planning health care quality interventions: a systematic literature review

    PubMed Central

    Mosavianpour, Mirkaber; Sarmast, Hamideh Helen; Kissoon, Niranjan; Collet, Jean-Paul

    2016-01-01

    Background Theoretical domains framework (TDF) provides an integrative model for assessing barriers to behavioral changes in order to suggest interventions for improvement in behavior and ultimately outcomes. However, there are other tools that are used to assess barriers. Objective The objective of this study is to determine the degree of concordance between domains and constructs identified in two versions of the TDF including original (2005) and refined version (2012) and independent studies of other tools. Methods We searched six databases for articles that studied barriers to health-related behavior changes of health care professionals or the general public. We reviewed quantitative papers published in English which included their questionnaires in the article. A table including the TDF domains of both original and refined versions and related constructs was developed to serve as a reference to describe the barriers assessed in the independent studies; descriptive statistics were used to express the results. Results Out of 552 papers retrieved, 50 were eligible to review. The barrier domains explored in these articles belonged to two to eleven domains of the refined TDF. Eighteen articles (36%) used constructs outside of the refined version. The spectrum of barrier constructs of the original TDF was broader and could meet the domains studied in 48 studies (96%). Barriers in domains of “environmental context and resources”, “beliefs about consequences”, and “social influences” were the most frequently explored in 42 (84%), 37 (74%), and 33 (66%) of the 50 articles, respectively. Conclusion Both refined and original TDFs cataloged barriers measured by the other studies that did not use TDF as their framework. However, the original version of TDF explored a broader spectrum of barriers than the refined version. From this perspective, the original version of the TDF seems to be a more comprehensive tool for assessing barriers in practice. PMID:27499628

  17. Theoretical domains framework to assess barriers to change for planning health care quality interventions: a systematic literature review.

    PubMed

    Mosavianpour, Mirkaber; Sarmast, Hamideh Helen; Kissoon, Niranjan; Collet, Jean-Paul

    2016-01-01

    Theoretical domains framework (TDF) provides an integrative model for assessing barriers to behavioral changes in order to suggest interventions for improvement in behavior and ultimately outcomes. However, there are other tools that are used to assess barriers. The objective of this study is to determine the degree of concordance between domains and constructs identified in two versions of the TDF including original (2005) and refined version (2012) and independent studies of other tools. We searched six databases for articles that studied barriers to health-related behavior changes of health care professionals or the general public. We reviewed quantitative papers published in English which included their questionnaires in the article. A table including the TDF domains of both original and refined versions and related constructs was developed to serve as a reference to describe the barriers assessed in the independent studies; descriptive statistics were used to express the results. Out of 552 papers retrieved, 50 were eligible to review. The barrier domains explored in these articles belonged to two to eleven domains of the refined TDF. Eighteen articles (36%) used constructs outside of the refined version. The spectrum of barrier constructs of the original TDF was broader and could meet the domains studied in 48 studies (96%). Barriers in domains of "environmental context and resources", "beliefs about consequences", and "social influences" were the most frequently explored in 42 (84%), 37 (74%), and 33 (66%) of the 50 articles, respectively. Both refined and original TDFs cataloged barriers measured by the other studies that did not use TDF as their framework. However, the original version of TDF explored a broader spectrum of barriers than the refined version. From this perspective, the original version of the TDF seems to be a more comprehensive tool for assessing barriers in practice.

  18. In Vivo Rectal Mucosal Barrier Function Imaging in a Large-Animal Model by Using Confocal Endomicroscopy: Implications for Injury Assessment and Use in HIV Prevention Studies

    PubMed Central

    Vincent, Kathleen Listiak; Zhu, Yong; Szafron, David; Brown, Tyra Caitlin; Villarreal, Paula Patricia; Bourne, Nigel; Milligan, Gregg N.; Motamedi, Massoud

    2016-01-01

    Injury occurring on the surface of the rectal mucosal lining that causes defects in barrier function may result in increased risk for transmission of infection by HIV and other pathogens. Such injury could occur from microbicidal or other topical agents, mechanical trauma during consensual or nonconsensual intercourse, or inflammatory conditions. Tools for evaluation of rectal mucosal barrier function for assessing the mucosa under these conditions are lacking, particularly those that can provide in vivo structural and functional barrier integrity assessment and are adaptable to longitudinal imaging. We investigated confocal endomicroscopy (CE) as a means for in vivo imaging of the rectal epithelial barrier in the ovine model following spatially confined injury to the surface at a controlled site using a topical application of the microbicide test agent benzalkonium chloride. Topical and intravenous (i.v.) fluorescent probes were used with CE to provide subcellular resolution imaging of the mucosal surface and assessment of barrier function loss. A 3-point CE grading system based on cellular structure integrity and leakage of dye through the mucosa showed significant differences in score between untreated (1.19 ± 0.53) and treated (2.55 ± 0.75) tissue (P < 0.0001). Histological grading confirmed findings of barrier compromise. The results indicate that CE is an effective means for detecting epithelial injury and barrier loss following localized trauma in a large-animal model. CE is promising for real-time rectal mucosal evaluation after injury or trauma or topical application of emerging biomedical prevention strategies designed to combat HIV. PMID:27185807

  19. Analysis of annual thermal and moisture performance of radiant barrier systems

    SciTech Connect

    Wilkes, K.E.

    1991-04-01

    This report summarizes a project to model the annual thermal and moisture performance of radiant barrier systems installed in residential attics. A previously developed model for the thermal performance of attics with radiant barriers was modified to allow estimates of moisture condensation on the underside of radiant barriers that are laid directly on top of existing attic insulation. The model was partially validated by comparing its predictions of ceiling heat flows and moisture condensation with data and visual observations made during a field experiment with full-size houses near Knoxville, Tennessee. Since the model predictions were found to be in reasonable agreement with the experimental data, the models were used to estimate annual energy savings and moisture accumulation rates for a wide variety of climatic conditions. The models results have been used to identify locations where radiant barriers are cost effective and also where radiant barriers have potential for causing moisture problems. 58 refs., 20 figs., 32 tabs.

  20. Analysis of annual thermal and moisture performance of radiant barrier systems

    SciTech Connect

    Wilkes, K.E. )

    1991-08-01

    This report summarizes a project to model the annual thermal and moisture performance of radiant barrier systems installed in residential attics. A previously developed model for the thermal performance of attics with radiant barriers was modified to allow estimates of moisture condensation on the underside of radiant barriers that are laid directly on top of existing attic insulation. The model was partially validated by comparing its predictions of ceiling heat flows and moisture condensation with data and visual observations made during a field experiment with full-size houses near Knoxville, Tennessee. Since the model predictions were found to be in reasonable agreement with the experimental data, the models were used to estimate annual energy savings and moisture accumulation rates for a wide variety of climatic conditions. The model results have been used to identify locations where radiant barriers are cost effective and also where radiant barriers have potential for causing moisture problems. 58 refs., 20 figs., 32 tabs.

  1. Assessment of institutional barriers to the use of natural gas fuel in automotive vehicle fleets

    NASA Technical Reports Server (NTRS)

    Jablonski, J.; Lent, L.; Lawrence, M.; White, L.

    1983-01-01

    Institutional barriers to the use of natural gas as a fuel for motor vehicle fleets were identified. Recommendations for barrier removal were developed. Eight types of institutional barriers were assessed: (1) lack of a national standard for the safe design and certification of natural gas vehicles and refueling stations; (2) excessively conservative or misapplied state and local regulations, including bridge and tunnel restrictions, restrictions on types of vehicles that may be fueled by natural gas, zoning regulations that prohibit operation of refueling stations, parking restrictions, application of LPG standards to LNG vehicles, and unintentionally unsafe vehicle or refueling station requirements; (3) need for clarification of EPA's tampering enforcement policy; (4) the U.S. hydrocarbon standard; (5) uncertainty concerning state utility commission jurisdiction; (6) sale for resale prohibitions imposed by natural gas utility companies or state utility commissions; (7) uncertainty of the effects of conversions to natural gas on vehicle manufactures warranties; and (8) need for a natural gas to gasoline equivalent units conversion factor for use in calculation of state road use taxes.

  2. Assessing barriers to care and readiness for cognitive behavioral therapy in early acute care PTSD interventions.

    PubMed

    Trusz, Sarah Geiss; Wagner, Amy W; Russo, Joan; Love, Jeff; Zatzick, Douglas F

    2011-01-01

    Cognitive Behavioral Therapy (CBT) interventions are efficacious in reducing posttraumatic stress disorder (PTSD) but are challenging to implement in acute care and other non-specialty mental health settings. This investigation identified barriers impacting CBT delivery through a content analysis of interventionist chart notes from an acute care PTSD prevention trial. Only 8.5% of all intervention patients were able to complete CBT. Lack of engagement, clinical and logistical barriers had the greatest impact on CBT entry. Treatment preferences and stigma only prevented entry when more primary barriers resolved. Patients with prior diagnosis of alcohol abuse or dependence were able to enter CBT after six months of sobriety. Based on the first trial, we developed a CBT readiness assessment tool. We implemented and evaluated the tool in a second early intervention trial. Lack of engagement emerged again as the primary impediment to CBT entry. Patients who were willing to enter CBT treatment but demonstrated high rates of past trauma or diagnosis of PTSD were also the least likely to engage in any PTSD treatment one month post-discharge. Findings support the need for additional investigations into engagement and alternative delivery strategies, including those which dismantle traditional office-based, multi-session CBT into stepped, deliverable components.

  3. Using skin models to assess the effects of a protection cream on skin barrier function.

    PubMed

    zur Mühlen, A; Klotz, A; Weimans, S; Veeger, M; Thörner, B; Diener, B; Hermann, M

    2004-01-01

    There is a basic necessity to understand the mechanisms of the protective effects of emulsions. This would promote the development of protective cosmetics and therefore improve the prevention and treatment of occupational skin diseases. However, for such studies, no reliable skin model is available. An in vitro skin model test was developed to evaluate the protective mechanism of cosmetic ingredients. The efficacy of three products was assessed by an in vivo test (Repetitive Occlusive Irritation Test) and then 3-dimensional skin model tests were carried out. In vivo test results demonstrate that the best protection against sodium dodecyl sulphate is offered by a multiple emulsion. In the case of a skin model test, sodium dodecyl sulphate led to cell damage, an increase in pro-inflammatory markers and some barrier lipids. The multiple emulsion increased the content of skin lipids, without inducing irritation or cell death. Skin models react similarly to sodium dodecyl sulphate compared to human skin and therefore they are suitable to study barrier repair after sodium dodecyl sulphate damage. It is likely that the superior protective effect of the multiple emulsion in vivo is based on the increased amount of skin barrier lipids.

  4. Expanded newborn screening in Puerto Rico and the US Virgin Islands: education and barriers assessment.

    PubMed

    Morales, Ana; Wierenga, Andrea; Cuthbert, Carla; Sacharow, Stephanie; Jayakar, Parul; Velazquez, Darcy; Loring, Jessica; Barbouth, Deborah

    2009-03-01

    The implementation of the expanded newborn screening panel of 29 disorders recommended by the American College of Medical Genetics in Puerto Rico and United States Virgin Islands is still in development or in early stages. Efforts in the territories are complicated by educational and resource barriers that generate a wide gap between the islands and the US mainland. To meet immediate educational needs, we conducted in-services for local newborn screening professionals. The efficacy of the educational intervention was measured by pre and posttest scores and a seminar evaluation. An assessment was obtained to document local newborn screening needs and barriers, with focus on human resources, intervention, language, social issues, education, and communication. Statistical significance was found (P value < or =0.05) between pre and posttest scores of the educational intervention. Needs and barriers associated with expanded newborn screening were also documented. Puerto Rico and United States Virgin Islands face different challenges in their implementation of expanded newborn screening. The data obtained in the present study serves as foundation for the development of public policy and long-term educational programs.

  5. A bioindicator system for water quality on inshore coral reefs of the Great Barrier Reef.

    PubMed

    Fabricius, Katharina E; Cooper, Timothy F; Humphrey, Craig; Uthicke, Sven; De'ath, Glenn; Davidson, Johnston; LeGrand, Hélène; Thompson, Angus; Schaffelke, Britta

    2012-01-01

    Responses of bioindicator candidates for water quality were quantified in two studies on inshore coral reefs of the Great Barrier Reef (GBR). In Study 1, 33 of the 38 investigated candidate indicators (including coral physiology, benthos composition, coral recruitment, macrobioeroder densities and FORAM index) showed significant relationships with a composite index of 13 water quality variables. These relationships were confirmed in Study 2 along four other water quality gradients (turbidity and chlorophyll). Changes in water quality led to multi-faceted shifts from phototrophic to heterotrophic benthic communities, and from diverse coral dominated communities to low-diversity communities dominated by macroalgae. Turbidity was the best predictor of biota; hence turbidity measurements remain essential to directly monitor water quality on the GBR, potentially complemented by our final calibrated 12 bioindicators. In combination, this bioindicator system may be used to assess changes in water quality, especially where direct water quality data are unavailable.

  6. Examining the Uptake of Central Nervous System Drugs and Candidates across the Blood-Brain Barrier.

    PubMed

    Summerfield, Scott G; Zhang, Yanyan; Liu, Houfu

    2016-08-01

    Assessing the equilibration of the unbound drug concentrations across the blood-brain barrier (Kp,uu) has progressively replaced the partition coefficient based on the ratio of the total concentration in brain tissue to blood (Kp). Here, in vivo brain distribution studies were performed on a set of central nervous system (CNS)-targeted compounds in both rats and P-glycoprotein (P-gp) genetic knockout mice. Several CNS drugs are characterized by Kp,uu values greater than unity, inferring facilitated uptake across the rodent blood-brain barrier (BBB). Examples are shown in which Kp,uu also increases above unity on knockout of P-gp, highlighting the composite nature of this parameter with respect to facilitated BBB uptake, efflux, and passive diffusion. Several molecules with high Kp,uu values share common structural elements, whereas uptake across the BBB appears more prevalent in the CNS-targeted drug set than the chemical templates being generated within the current lead optimization paradigm. Challenges for identifying high Kp,uu compounds are discussed in the context of acute versus steady-state data and cross-species differences. Evidently, there is a need for better predictive models of human brain Kp,uu. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  7. Overcoming Barriers: Adolescents’ Experiences Using a Mobile Phone Dietary Assessment App

    PubMed Central

    Svensson, Åsa; Magnusson, Maria

    2016-01-01

    Background The use of new technology has the potential to increase participation rates in dietary studies and improve the validity of collected dietary data. However, to evaluate the usability of developed dietary methods, qualitative studies of participants’ experiences and perceptions are needed. Objective To explore adolescents’ experiences using a newly developed mobile phone dietary assessment app, with a focus on factors that could affect their recording of dietary intake. Methods Focus group interviews were conducted with 75 participants who had used a newly developed mobile phone dietary assessment app in a quantitative evaluation study. The interviews were analyzed using qualitative content analysis and the theoretical framework of Self Determination Theory was applied. Results The adolescents’ use of the mobile phone dietary assessment app was characterized by their struggle to overcome several perceived barriers. Facilitators that helped adolescents complete the method were also identified. Motivation was found to be an important facilitator, and intrinsically motivated participants completed the method because they found it fun to use. The autonomous extrinsically motivated participants completed the method for the greater good, in order to contribute to the study. The controlled extrinsically motivated participants completed the method to get a reward or avoid punishment. Amotivated participants did not complete the method. More motivated participants were assumed to be more able to overcome barriers and needed less facilitators. Conclusions Future studies that examine the recording of food intake should include systematic efforts that aim to minimize identified barriers and promote identified facilitators. Further research should specifically aim at studying methods for (and effects of) increasing intrinsic motivation by supporting autonomy, competence, and relatedness among adolescents asked to participate in dietary studies. PMID:27473462

  8. Overcoming Barriers: Adolescents' Experiences Using a Mobile Phone Dietary Assessment App.

    PubMed

    Svensson, Åsa; Magnusson, Maria; Larsson, Christel

    2016-07-29

    The use of new technology has the potential to increase participation rates in dietary studies and improve the validity of collected dietary data. However, to evaluate the usability of developed dietary methods, qualitative studies of participants' experiences and perceptions are needed. To explore adolescents' experiences using a newly developed mobile phone dietary assessment app, with a focus on factors that could affect their recording of dietary intake. Focus group interviews were conducted with 75 participants who had used a newly developed mobile phone dietary assessment app in a quantitative evaluation study. The interviews were analyzed using qualitative content analysis and the theoretical framework of Self Determination Theory was applied. The adolescents' use of the mobile phone dietary assessment app was characterized by their struggle to overcome several perceived barriers. Facilitators that helped adolescents complete the method were also identified. Motivation was found to be an important facilitator, and intrinsically motivated participants completed the method because they found it fun to use. The autonomous extrinsically motivated participants completed the method for the greater good, in order to contribute to the study. The controlled extrinsically motivated participants completed the method to get a reward or avoid punishment. Amotivated participants did not complete the method. More motivated participants were assumed to be more able to overcome barriers and needed less facilitators. Future studies that examine the recording of food intake should include systematic efforts that aim to minimize identified barriers and promote identified facilitators. Further research should specifically aim at studying methods for (and effects of) increasing intrinsic motivation by supporting autonomy, competence, and relatedness among adolescents asked to participate in dietary studies.

  9. Barrier function in the peripheral and central nervous system-a review.

    PubMed

    Reinhold, A K; Rittner, H L

    2017-01-01

    The peripheral (PNS) and central nervous system (CNS) are delicate structures, highly sensitive to homeostatic changes-and crucial for basic vital functions. Thus, a selection of barriers ensures the protection of the nervous system from noxious blood-borne or surrounding stimuli. In this chapter, anatomy and functioning of the blood-nerve (BNB), the blood-brain (BBB), and the blood-spinal cord barriers (BSCB) are presented and the key tight junction (TJ) proteins described: claudin-1, claudin-3, claudin-5, claudin-11, claudin-12, claudin-19, occludin, Zona occludens-1 (ZO-1), and tricellulin are by now identified as relevant for nerval barriers. Different diseases can lead to or be accompanied by neural barrier disruption, and impairment of these barriers worsens pathology. Peripheral nerve injury and inflammatory polyneuropathy cause an increased permeability of BNB as well as BSCB, while, e.g., diseases of the CNS such as amyotrophic lateral sclerosis, multiple sclerosis, spinal cord injury, or Alzheimer's disease can progress and worsen through barrier dysfunction. Moreover, the complex role and regulation of the BBB after ischemic stroke is described. On the other side, PNS and CNS barriers hamper the delivery of drugs in diseases when the barrier is intact, e.g., in certain neurodegenerative diseases or inflammatory pain. Understanding of the barrier - regulating processes has already lead to the discovery of new molecules as drug enhancers. In summary, the knowledge of all of these mechanisms might ultimately lead to the invention of drugs to control barrier function to help ameliorating or curing neurological diseases.

  10. Barriers to treatment adherence among African American and white women with systemic lupus erythematosus.

    PubMed

    Mosley-Williams, Angelia; Lumley, Mark A; Gillis, Mazy; Leisen, James; Guice, Deena

    2002-12-15

    To determine whether African Americans with systemic lupus erythematosus (SLE) have poorer treatment adherence than whites, and to determine ethnic group differences in barriers to adherence, and how barriers affect adherence. We compared 68 African American and 54 white women with SLE on 19 potential barriers, on 2 adherence behaviors during the past year, and on how the potential barriers relate to each nonadherence behavior. African Americans and whites were similar on most barriers, although African Americans were more likely to rely on religion and were more concerned about long-term medication effects. The 2 ethnic groups were comparable on medication nonadherence, but whites tended to have poorer clinic appointment adherence than African Americans. Finally, we found that barriers related to negative affect (depression, medication concerns, physical symptoms) as well as short-term memory problems and the need for child or elder care were associated with nonadherence among African Americans, whereas perceived treatment inefficacy and lacking trust in physicians were associated with nonadherence among whites. Relationships between adherence barriers and nonadherence may be ethnicity specific, suggesting that interventions to address barriers should be targeted to specific groups.

  11. Condition Assessment Information System

    SciTech Connect

    Rowe, Kenneth; McDermitt, Dennis

    2002-09-16

    CAIS2000 records, tracks and cost maintenance deficiencies associated with condition assessments of real property assets. Cost information is available for 39,000 items in the currenht RS Means, Facilities Construction Manual. These costs can, in turn, be rolled by by asset to produce the summary condition of an asset or site.

  12. Technology and Effective Assessment Systems

    ERIC Educational Resources Information Center

    Baker, Eva L.

    2005-01-01

    Over the last 20 years, writing about technology (and more recently about its use in assessment systems) has been a joyful experience, in part because the author was usually right about how fast and how unexpected technology progress would be made. In this article, the author suggests to rethink assessment systems from design perspectives and the…

  13. Reactive barrier system for nitrate removal from mine effluents in northern Sweden: Laboratory experiments

    NASA Astrophysics Data System (ADS)

    Herbert, Roger

    2010-05-01

    Laboratory column experiments have been conducted to determine nitrate removal rates from mine effluents by denitrification, with the purpose of providing initial data for the construction of a pilot scale reactive barrier system at the Malmberget iron mine, Sweden. Experiments were conducted at several different flow rates at 5C, 10C and room temperature; annual mean temperatures at the Malmberget site lie close to 0C. Columns were filled with an organic substrate consisting of sawdust mixed with sewage sludge, the source of denitrifying bacteria, supported by oven-dried clay pellets. Apparent denitrification rates, calculated from inflow and outflow nitrate concentrations and column hydraulic residence time, ranged from 5 to 13 mg N/L/d, with the lowest rates corresponding to the 5C experiments. These rates are, however, limited to a certain degree by the low flow rate and the supply of electrons acceptors (i.e. nitrate) to denitrifying bacteria. Results from the column experiment have been used to construct a barrier system in Malmberget, Sweden. Trial runs with the pilot-scale barrier will be conducted during 2010, with the purpose of determining the performance of the barrier as mean air temperatures increase from below to above 0C and saturated flow commences in the barrier. The barrier system is constructed as a rectangular container with steel sheet walls (9m length in flow direction, 1.5m deep), and the flow rate will be adjusted to a hydraulic residence time of 1 day. The pilot-scale barrier system currently lies above ground, but a permanent barrier system would be installed below the ground surface so that the system can be maintained at positive temperatures throughout the year.

  14. Questionnaires used to assess barriers of clinical guideline use among physicians are not comprehensive, reliable, or valid: a scoping review.

    PubMed

    Willson, Melina L; Vernooij, Robin W M; Gagliardi, Anna R

    2017-06-01

    This study described the number and characteristics of questionnaires used to assess barriers of guideline use among physicians. A scoping review was conducted. MEDLINE and EMBASE were searched from 2005 to June 2016. English-language studies that administered a questionnaire to assess barriers of guideline use among practicing physicians were eligible. Summary statistics were used to report study and questionnaire characteristics. Questionnaire content was assessed with a checklist of 57 known barriers. Each of the 178 included studies administered a unique questionnaire. The number of questionnaires increased yearly from 2005 to 2015. Few were pilot-tested (50, 28.1%) or tested for psychometric properties (3, 1.7%). Two were based on theory. None probed for the full range of known barriers. Ten included a free-text option. The majority assessed professional barriers (177, 99.4%) but few of the 14 factors within this domain. Questionnaire characteristics did not change over time. Organizations administered questionnaires that were not reliable or valid and did not comprehensively assess barriers and may have selected interventions unlikely to promote guideline use. Research is needed to construct a questionnaire that is practical, adaptable, and robust and leads to the selection of interventions that support guideline use. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Assessment information systems

    NASA Technical Reports Server (NTRS)

    Danhof, C. H.

    1972-01-01

    The assessment process in contemporary society and the role of the expert are discussed. The development of technology is considered in two stages: the preintroduction stage in which the developer makes the tests and decisions, and the application stage in which the user applies the technology and makes tests with different criteria. The adverse effects of death, personal injury, and collective injury are described, and resulting public actions are mentioned. The role of the experts is identified as asking relevant questions and recording observations, communicating with each other, summarizing the findings, and indicating the significance of the findings to those capable of deciding upon action. It is pointed out that the experts often disagree on facts and economic values. The basic problem is felt to be one of identifying the social significance in an assessment situation.

  16. Chasing boundaries and cascade effects in a coupled barrier-marsh-lagoon system

    NASA Astrophysics Data System (ADS)

    Lorenzo-Trueba, Jorge; Mariotti, Giulio

    2017-08-01

    The long-term dynamic evolution of an idealized barrier-marsh-lagoon system experiencing sea-level rise is studied by coupling two existing numerical models. The barrier model accounts for the interaction between shoreface dynamics and overwash flux, which allows the occurrence of barrier drowning. The marsh-lagoon model includes both a backbarrier marsh and an interior marsh, and accounts for the modification of the wave regime associated with changes in lagoon width and depth. Overwash, the key process that connects the barrier shoreface with the marsh-lagoon ecosystems, is formulated to account for the role of the backbarrier marsh. Model results show that a number of factors that are not typically associated with the dynamics of coastal barriers can enhance the rate of overwash-driven landward migration by increasing backbarrier accommodation space. For instance, lagoon deepening could be triggered by marsh edge retreat and consequent export of fine sediment via tidal dispersion, as well as by an expansion of inland marshes and consequent increase in accommodation space to be filled in with sediment. A deeper lagoon results in a larger fraction of sediment overwash being subaqueous, which coupled with a slow shoreface response sending sediment onshore can trigger barrier drowning. We therefore conclude that the supply of fine sediments to the back-barrier and the dynamics of both the interior and backbarrier marsh can be essential for maintaining the barrier system under elevated rates of sea-level rise. Our results highlight the importance of considering barriers and their associated backbarriers as part of an integrated system in which sediment is exchanged.

  17. Breast cancer risk assessments to barrier contraception exposure. A new approach.

    PubMed

    Gjorgov, N A

    2009-07-01

    (Full text is available at http://www.manu.edu.mk/prilozi). The risk prediction models for breast cancer remain unsatisfactory. The existing models of breast cancer risk assessment have failed to consider (calculate) the exposure to condom use, defined as the major risk factor of breast cancer. All the models, including the NCI-Gail model, are based on the so-called "known" breast cancer risk factors, such as, menarche, age at first birth, parity, OC pills, diet, physical activity, age at menopause, number of breast biopsies, family history, ethnicity (race), age and other. The commonest predictions of the models has been that "All women are at risk of breast cancer," which is deemed as a patently incorrect assessment. The risk assessments have served for identification and recruitment of women at "elevated risk" of breast cancer both for therapeutic randomized clinical trials (RCTs), and for implementing a possible clinical policy of "prophylactic" mastectomy and other prior surgical interventions. However, the models have raised questions lately about their adequacy and practical usefulness, because of the use of "weak" and inadequate risk factors. This study presents the results of a new approach and alternative model and results to the risk assessment of breast cancer, by calculating the exposure to barrier contraceptive practice (condom use and withdrawal practice) along with the factors of parity, age and other (non-barrier) birth-control methods, within a 5-year time period and the life span 20-54 years of age, by employing the Bayes' Probability Theorem. Key words: Breast cancer, Risk Assessment, New Approach, Bayes' Theorem, Parity, Condom Risk Factor, Primary prevention.

  18. Understanding Barriers to Evidence-Based Assessment: Clinician Attitudes toward Standardized Assessment Tools

    ERIC Educational Resources Information Center

    Jensen-Doss, Amanda; Hawley, Kristin M.

    2010-01-01

    In an era of evidence-based practice, why are clinicians not typically engaged in evidence-based assessment? To begin to understand this issue, a national multidisciplinary survey was conducted to examine clinician attitudes toward standardized assessment tools. There were 1,442 child clinicians who provided opinions about the psychometric…

  19. Understanding Barriers to Evidence-Based Assessment: Clinician Attitudes toward Standardized Assessment Tools

    ERIC Educational Resources Information Center

    Jensen-Doss, Amanda; Hawley, Kristin M.

    2010-01-01

    In an era of evidence-based practice, why are clinicians not typically engaged in evidence-based assessment? To begin to understand this issue, a national multidisciplinary survey was conducted to examine clinician attitudes toward standardized assessment tools. There were 1,442 child clinicians who provided opinions about the psychometric…

  20. Advances in the Dynallax solid-state dynamic parallax barrier autostereoscopic visualization display system.

    PubMed

    Peterka, Tom; Kooima, Robert L; Sandin, Daniel J; Johnson, Andrew; Leigh, Jason; DeFanti, Thomas A

    2008-01-01

    A solid-state dynamic parallax barrier autostereoscopic display mitigates some of the restrictions present in static barrier systems, such as fixed view-distance range, slow response to head movements, and fixed stereo operating mode. By dynamically varying barrier parameters in real time, viewers may move closer to the display and move faster laterally than with a static barrier system, and the display can switch between 3D and 2D modes by disabling the barrier on a per-pixel basis. Moreover, Dynallax can output four independent eye channels when two viewers are present, and both head-tracked viewers receive an independent pair of left-eye and right-eye perspective views based on their position in 3D space. The display device is constructed by using a dual-stacked LCD monitor where a dynamic barrier is rendered on the front display and a modulated virtual environment composed of two or four channels is rendered on the rear display. Dynallax was recently demonstrated in a small-scale head-tracked prototype system. This paper summarizes the concepts presented earlier, extends the discussion of various topics, and presents recent improvements to the system.

  1. Proxy records of Holocene storm events in coastal barrier systems: Storm-wave induced markers

    NASA Astrophysics Data System (ADS)

    Goslin, Jérôme; Clemmensen, Lars B.

    2017-10-01

    Extreme storm events in the coastal zone are one of the main forcing agents of short-term coastal system behavior. As such, storms represent a major threat to human activities concentrated along the coasts worldwide. In order to better understand the frequency of extreme events like storms, climate science must rely on longer-time records than the century-scale records of instrumental weather data. Proxy records of storm-wave or storm-wind induced activity in coastal barrier systems deposits have been widely used worldwide in recent years to document past storm events during the last millennia. This review provides a detailed state-of-the-art compilation of the proxies available from coastal barrier systems to reconstruct Holocene storm chronologies (paleotempestology). The present paper aims (I) to describe the erosional and depositional processes caused by storm-wave action in barrier and back-barrier systems (i.e. beach ridges, storm scarps and washover deposits), (ii) to understand how storm records can be extracted from barrier and back-barrier sedimentary bodies using stratigraphical, sedimentological, micro-paleontological and geochemical proxies and (iii) to show how to obtain chronological control on past storm events recorded in the sedimentary successions. The challenges that paleotempestology studies still face in the reconstruction of representative and reliable storm-chronologies using these various proxies are discussed, and future research prospects are outlined.

  2. Long-Term Climate Change Assessment Task for the Hanford Site Permanent Isolation Barrier Development Program: Status through FY 1992

    SciTech Connect

    Petersen, K.L.; Chatters, J.C.

    1993-07-01

    The Hanford Site Permanent Isolation Barrier Development Program (Barrier Development Program) was organized (Adams and Wing 1986) to develop the technology needed to provide an in-place disposal capability for the US Department of Energy at the Hanford Site in southeastern Washington. The goals of the Barrier Development Program are to provide defensible evidence that final barrier design(s) will adequately control water infiltration, plant and animal intrusion, and wind and water erosion for a minimum of 1,000 years; to isolate wastes from the accessible environment; and to use markers to warn inadvertent human intruders. Evidence for barrier performance will be obtained by conducting laboratory experiments, field tests, computer modeling, and other studies that establish confidence in the barrier`s ability to meet its 1,000-year design life. The performance and stability of natural barrier analogs that have existed for several millennia and the reconstruction of climate changes during the past 10,000 to 125,000 years also will provide insight into bounding conditions of possible future changes and increase confidence in the barriers design. In the following discussion the term {open_quotes}long-term{close_quotes} references periods of time up to 1000`s of years, distinguishing it from {open_quotes}short-term{close_quotes} weather patterns covering a decade or less. Specific activities focus on planning and conducting a series of studies and tests required to confirm key aspects of the barrier design. The effort is a collaborative one between scientists and engineers from Westinghouse Hanford Company (Westinghouse Hanford) and Pacific Northwest Laboratory (PNL) to design barriers to limit movement of radionuclides and other contaminants to the accessible environment for at least 1,000 years. These activities have been divided into 14 groups of tasks that aid in the complete development of protective barrier and warning marker system.

  3. Workplace barriers encountered by employed persons with systemic sclerosis.

    PubMed

    Poole, Janet L; Anwar, Sahar; Mendelson, Cindy; Allaire, Saralynn

    2016-01-01

    Systemic sclerosis (SSc) is an auto-immune connective tissue disease characterized by fibrosis of skin, blood vessels, and internal organs that results in significant disability. To identify the work barriers faced by people with systemic sclerosis (SSc) in maintaining employment. Thirty-six people with SSc who were working more than 8 hours per week completed the Work Experience Survey, which contains lists of potential work barriers, including the ability to travel to and from work; get around at work; perform essential job functions, including physical, cognitive, and task-related activities; work with others; and manage work conditions. Thirty-three participants completed and returned the questionnaires, most of whom were female, and working full time and in professional careers. Principal disease symptoms included fatigue, Raynaud's phenomenon, esophageal involvement, and leg or hand/wrist pain. All participants reported some barriers with a mean of 18 barriers per participant. At least three quarters of participants cited outside temperature (82%), cold temperatures inside the workplace (76%), and household work (76%), as barriers. The next most common barriers were using both hands (64%), arranging and taking part in social activities (64%), being able to provide self-care (61%) and working 8 hours (58%). Participants reported a wide range of barriers, from cold temperatures, to physical job, fatigue related, and non-workplace demands, in maintaining the worker role. The barriers reflect the disease symptoms they reported. Identifying workplace barriers facilitates the creation of job accommodations or adaptations that will allow people with SSc to continue working.

  4. Identifying Occupational Performance Barriers of Stroke Survivors: Utilization of a Home Assessment

    PubMed Central

    Hersch, Gayle I.; Foust, Jessica L.; Wyatt, Alicia L.; Godwin, Kyler M.; Virani, Salimah; Ostwald, Sharon K.

    2013-01-01

    Background Stroke survivors often have impairments that make it difficult for them to function safely in their home environment. Purpose The purpose of this study is to identify occupational performance barriers in the home and describe the subsequent recommendations offered to stroke survivors and their caregivers. Methods An occupational therapist administered a home safety tool to assess stroke survivors' home environments, determine home safety problems, and provide recommendations. Findings Among 76 stroke survivors, the greatest problems were indentified in the categories of bathroom, mobility, and communication. Two case studies illustrate the use of the home safety tool with this population. Implications The home safety tool is helpful in determining the safety needs of stroke survivors living at home. We recommend the use of the home safety tool for occupational therapists assessing the safety of the home environment. PMID:24285912

  5. Identifying Occupational Performance Barriers of Stroke Survivors: Utilization of a Home Assessment.

    PubMed

    Schulz, Celia H; Hersch, Gayle I; Foust, Jessica L; Wyatt, Alicia L; Godwin, Kyler M; Virani, Salimah; Ostwald, Sharon K

    2012-06-01

    Stroke survivors often have impairments that make it difficult for them to function safely in their home environment. The purpose of this study is to identify occupational performance barriers in the home and describe the subsequent recommendations offered to stroke survivors and their caregivers. An occupational therapist administered a home safety tool to assess stroke survivors' home environments, determine home safety problems, and provide recommendations. Among 76 stroke survivors, the greatest problems were indentified in the categories of bathroom, mobility, and communication. Two case studies illustrate the use of the home safety tool with this population. The home safety tool is helpful in determining the safety needs of stroke survivors living at home. We recommend the use of the home safety tool for occupational therapists assessing the safety of the home environment.

  6. Attitudinal & Knowledge Barriers towards Effective Pain Assessment & Management in Dementia: A Narrative Synthesis.

    PubMed

    Chandler, Rebecca C; Zwakhalen, Sandra Mg; Docking, Rachael; Bruneau, Benjamin; Schofield, Patricia

    2016-06-02

    Under-assessment and inadequate treatment of pain is a common problem for older adults, particularly those with dementia. This may be in part attributed to knowledge deficits and negative attitudes among healthcare staff and informal caregivers towards pain, its assessment and its management in dementia. Knowledge and attitudes have a significant predictive relationship with behavior, potentially impacting pain assessment and management practices. Despite this there remains a paucity of research in the area and a lack of clarity about existing knowledge levels and attitudes among dementia caregivers. Therefore, the aims of this review were to: identify what knowledge deficits and attitudinal barriers exist amongst dementia caregivers; and identify the scales available to measure these. A search was carried out in the following electronic databases: Academic Search Premier; CINAHL; Education Research Complete; Humanities International Journals; Psychology and Behavioral Sciences Collection; PsychINFO; PsychArticles; Teacher Reference Center; and MEDLINE. A total of 13 articles met the inclusion criteria. A number of knowledge deficits and negative attitudes were identified, particularly in the use self-reports and pain assessment tools in dementia, and the safety of opioids. Understanding and positive attitudes were demonstrated in some areas, such as non-narcotic pain medications and identifying behavioral pain indicators. Of the 4 scales identified, positive results were found for internal consistency and content validity, however further refinement and testing is necessary. It was concluded attitudinal and knowledge barriers exist which should be addressed given their influence over practice behavior, however, there is a willingness and knowledge base from which progress can build.

  7. Video systems for alarm assessment

    SciTech Connect

    Greenwoll, D.A.; Matter, J.C. ); Ebel, P.E. )

    1991-09-01

    The purpose of this NUREG is to present technical information that should be useful to NRC licensees in designing closed-circuit television systems for video alarm assessment. There is a section on each of the major components in a video system: camera, lens, lighting, transmission, synchronization, switcher, monitor, and recorder. Each section includes information on component selection, procurement, installation, test, and maintenance. Considerations for system integration of the components are contained in each section. System emphasis is focused on perimeter intrusion detection and assessment systems. A glossary of video terms is included. 13 figs., 9 tabs.

  8. Noncontacting Laser Inspection System for Dimensional Profiling of Space Application Thermal Barriers

    NASA Technical Reports Server (NTRS)

    Taylor, Shawn C.

    2011-01-01

    A noncontacting, two-dimensional (2-D) laser inspection system has been designed and implemented to dimensionally profile thermal barriers being developed for space vehicle applications. In a vehicle as-installed state, thermal barriers are commonly compressed between load sensitive thermal protection system (TPS) panels to prevent hot gas ingestion through the panel interface during flight. Loads required to compress the thermal barriers are functions of their construction, as well as their dimensional characteristics relative to the gaps in which they are installed. Excessive loads during a mission could damage surrounding TPS panels and have catastrophic consequences. As such, accurate dimensional profiling of thermal barriers prior to use is important. Due to the compliant nature of the thermal barriers, traditional contact measurement techniques (e.g., calipers and micrometers) are subjective and introduce significant error and variability into collected dimensional data. Implementation of a laser inspection system significantly enhanced the method by which thermal barriers are dimensionally profiled, and improved the accuracy and repeatability of collected data. A statistical design of experiments study comparing laser inspection and manual caliper measurement techniques verified these findings.

  9. Perceptions of physicians about knowledge sharing barriers in Turkish health care system.

    PubMed

    Gider, Ömer; Ocak, Saffet; Top, Mehmet

    2015-05-01

    This study was based on knowledge sharing barriers about attitudes of physicians in Turkish health care system. The present study aims to determine whether the knowledge sharing barriers about attitudes of physicians vary depending on gender, position, departments at hospitals, and hospital ownership status. This study was planned and conducted on physicians at one public hospital, one university hospital, and one private hospital in Turkey. 209 physicians were reached for data collection. The study was conducted in June-September 2014. The questionnaire (developed by A. Riege, (J. Knowl. Manag. 9(3):18-35, 2005)), five point Likert-type scale including 39 items having the potential of the physicians' knowledge- sharing attitudes and behaviors, was used in the study for data collection. Descriptive statistics, reliability analysis, student t test and ANOVA were used for data analysis. According to results of this study, there was medium level of knowledge sharing barriers within hospitals. In general, physicians had perceptions about the lowest level individual barriers, intermediate level organizational barriers and the highest level technological barriers perceptions, respectively. This study revealed that some knowledge sharing barriers about attitudes of physicians were significantly difference according to hospital ownership status, gender, position and departments. Most evidence medical decisions and evidence based practice depend on experience and knowledge of existing options and knowledge sharing in health care organizations. Physicians are knowledge and information-intensive and principal professional group in health care context.

  10. Understanding barriers to evidence-based assessment: Clinician attitudes toward standardized assessment tools

    PubMed Central

    Jensen-Doss, Amanda; Hawley, Kristin M.

    2010-01-01

    In an era of evidence-based practice, why are clinicians not typically engaged in evidence-based assessment? To begin to understand this issue, a national multidisciplinary survey was conducted to examine clinician attitudes toward standardized assessment tools. 1442 child clinicians provided opinions about the psychometric qualities of these tools, their benefit over clinical judgment alone, and their practicality. Doctoral-level clinicians and psychologists expressed more positive ratings in all three domains than master’s-level clinicians and non-psychologists respectively, although only the disciplinary differences remained significant when predictors were examined simultaneously. All three attitude scales were predictive of standardized assessment tool use, although practical concerns were the strongest and only independent predictor of use. PMID:21058134

  11. Assessing barriers to change in drinking behavior: results of an online employee screening program.

    PubMed

    Aseltine, Robert H; Demarco, Frank J; Wallenstein, Gene V; Jacobs, Douglas G

    2009-01-01

    The impact of alcohol abuse on worker productivity is considerable and appears to be increasing over time. Although early screening and intervention may help prevent or reduce the damaging health and productivity effects of problem drinking, barriers to behavioral change may render broad-based prevention efforts ineffectual. This study examined the correlates of two potential barriers to changes in drinking behavior--underestimation of drinking and lack of knowledge of helping resources--using data from web-based employee alcohol screenings. Anonymous screening data from 1185 employees of ten companies participating in the 2003 National Alcohol Screening Day were analyzed. The AUDIT, a 10-item screening instrument developed by the World Health Organization, was used to measure drinking behavior; employees' subjective assessments of their drinking were also obtained. Over 53% of participants subjectively underestimated their drinking relative to their AUDIT results, and 58% of respondents did not know whether their medical insurance included benefits for alcohol treatment. Logistic regression analysis revealed that younger and male respondents tended to have the highest AUDIT scores and also (along with married respondents) were most likely to underestimate their drinking. Younger, unmarried respondents were least likely to be aware of their alcohol treatment insurance benefits. Current corporate efforts to curtail problem drinking among employees may not adequately address barriers to change. Targeting at-risk employee groups for alcohol screening and dissemination of information about health insurance benefits and treatment options is recommended, as is providing personalized feedback based on screening results to raise awareness of at-risk drinking and available helping resources.

  12. Assessment of active play, inactivity and perceived barriers in an inner city neighborhood

    PubMed Central

    Kottyan, Gregg; Kottyan, Leah; Edwards, Nicholas M.; Unaka, Ndidi I.

    2014-01-01

    Avondale, a disadvantaged neighborhood in Cincinnati, lags behind on a number of indicators of child well-being. Childhood obesity has become increasingly prevalent, as one third of Avondale’s kindergarteners are obese or overweight. The study objective was to determine perceptions of the quantity of and obstacles to childhood physical activity in the Avondale community. Caregivers of children from two elementary schools were surveyed to assess their child’s physical activity and barriers to being active. Three hundred forty surveys were returned out of 1,047 for a response rate of 32%. On school days, 41% of caregivers reported that their children spent more than 2 hours watching television, playing video games, or spending time on the computer. While over half of respondents reported that their children get more than 2 hours of physical activity on school days, 14% of children were reported to be physically active less than 1 hour per day. Caregivers identified violence, cost of extracurricular activities, and lack of organized activities as barriers to their child’s physical activity. The overwhelming majority of caregivers expressed interest in a program to make local playgrounds safer. In conclusion, children in Avondale are not participating in enough physical activity and are exposed to more screen time than is recommended by the AAP. Safety concerns were identified as a critical barrier to address in future advocacy efforts in this community. This project represents an important step toward increasing the physical activity of children in Avondale and engaging the local community. PMID:24306236

  13. Barriers to Serving Clients With Co-occurring Disorders in a Transformed Mental Health System

    PubMed Central

    Padwa, Howard; Guerrero, Erick G.; Braslow, Joel T.; Fenwick, Karissa M.

    2015-01-01

    Objective The publication of the President’s New Freedom Commission Report in 2003 led to hope and anticipation that system transformation would address barriers that have impeded the delivery of integrated services for clients with co-occurring mental health and substance use disorders. Have problems been resolved? This study analyzed providers’ perspectives on serving clients with co-occurring disorders in a large mental health system that has undergone transformation. Methods Six focus groups were conducted with providers at specialty mental health treatment organizations that received funding to transform services. Using content analysis, the authors identified major themes of the focus group discussions. Results Participants reported several barriers within the mental health system and challenges associated with collaborating with specialty substance abuse treatment providers that impede the delivery of integrated care. Conclusions In spite of efforts to improve co-occurring disorder service delivery in a transformed mental health system, barriers that have historically impeded integrated treatment persist. PMID:25686812

  14. Effect of vadose zone on the steady-state leakage rates from landfill barrier systems.

    PubMed

    Celik, B; Rowe, R K; Unlü, K

    2009-01-01

    Leakage rates are evaluated for a landfill barrier system having a compacted clay liner (CCL) underlain by a vadose zone of variable thickness. A numerical unsaturated flow model SEEP/W is used to simulate the moisture flow regime and steady-state leakage rates for the cases of unsaturated zones with different soil types and thicknesses. The results of the simulations demonstrate that harmonic mean hydraulic conductivity of coarse textured vadose zones is 3-4 orders of magnitude less than saturated hydraulic conductivity; whereas, the difference is only one order of magnitude for fine textured vadose zones. For both coarse and fine textured vadose zones, the effective hydraulic conductivity of the barrier system and the leakage rate to an underlying aquifer increases with increasing thickness of the vadose zone and ultimately reaches an asymptotic value for a coarse textured vadose zone thickness of about 10m and a fine textured vadose zone thickness of about 5m. Therefore, the fine and coarse textured vadose zones thicker than about 5m and 10m, respectively, act as an effective part of the barrier systems examined. Although the thickness of vadose zone affects the effective hydraulic conductivity of the overall barrier system, the results demonstrated that the hydraulic conductivity of the CCL is the dominant factor controlling the steady-state leakage rates through barrier systems having single low permeability clay layers.

  15. In-situ defect detection systems for R2R flexible PV barrier films

    NASA Astrophysics Data System (ADS)

    Gao, F.; Muhamedsalih, H.; Tang, D.; Elrawemi, M.; Blunt, L.; Jiang, X.; Edge, S.; Bird, D.; Hollis, P.

    2015-08-01

    Film processing procedures by means of Roll-to-Roll (R2R) for barrier coatings can often result in PV barrier films being manufactured with significant quantities of defects, which results in lower efficiency and a short life span. In order to improve the process yield and product efficiency, it is desirable to develop an inspection system that can detect transparent barrier film defects in the production line during film processing. Off-line detection of defects in transparent PV barrier films is difficult and time consuming. Consequently, implementing an accurate in-situ defects inspection system in the production environment is even more challenging, since the requirements on positioning, fast measurement, long term stability and robustness against environmental disturbance are demanding. This paper reports on the development and deployment of two in-situ PV barrier films defect detection systems, one based on wavelength scanning interferometry (WSI) and the other on White Light Channeled Spectral Interferometry (WLCSI), and the integration into an R2R film processing line at the Centre for Process Innovation (CPI). The paper outlines the environmental vibration strategy for both systems, and the developed auto-focusing methodology for WSI. The systems have been tested and characterised and initial results compared to laboratory-based instrumentation are presented.

  16. Effect of vadose zone on the steady-state leakage rates from landfill barrier systems

    SciTech Connect

    Celik, B. Rowe, R.K. Unlue, K.

    2009-01-15

    Leakage rates are evaluated for a landfill barrier system having a compacted clay liner (CCL) underlain by a vadose zone of variable thickness. A numerical unsaturated flow model SEEP/W is used to simulate the moisture flow regime and steady-state leakage rates for the cases of unsaturated zones with different soil types and thicknesses. The results of the simulations demonstrate that harmonic mean hydraulic conductivity of coarse textured vadose zones is 3-4 orders of magnitude less than saturated hydraulic conductivity; whereas, the difference is only one order of magnitude for fine textured vadose zones. For both coarse and fine textured vadose zones, the effective hydraulic conductivity of the barrier system and the leakage rate to an underlying aquifer increases with increasing thickness of the vadose zone and ultimately reaches an asymptotic value for a coarse textured vadose zone thickness of about 10 m and a fine textured vadose zone thickness of about 5 m. Therefore, the fine and coarse textured vadose zones thicker than about 5 m and 10 m, respectively, act as an effective part of the barrier systems examined. Although the thickness of vadose zone affects the effective hydraulic conductivity of the overall barrier system, the results demonstrated that the hydraulic conductivity of the CCL is the dominant factor controlling the steady-state leakage rates through barrier systems having single low permeability clay layers.

  17. Barriers to the Operation of Patient Safety Incident Reporting Systems in Korean General Hospitals

    PubMed Central

    Hwang, Jee-In; Lee, Sang-IL

    2012-01-01

    Objectives This study aimed to explore the barriers to and factors facilitating the operation of patient safety incident reporting systems. Methods A qualitative study that used a methodological triangulation method was conducted. Participants were those who were involved in or responsible for managing incident reporting at hospitals, and they were recruited via a snowballing sampling method. Data were collected via interviews or emails from 42 nurses at 42 general hospitals. A qualitative content analysis was performed to derive the major themes related to barriers to and factors facilitating incident reporting. Results Participants suggested 96 barriers to incident reporting in their hospitals at the organizational and individual levels. Low reporting rates, especially for near misses, were the most commonly reported issue, followed by poorly designed incident reporting systems and a lack of adequate patient safety leadership by mid-level managers. To resolve and overcome these barriers, 104 recommendations were suggested. The high-priority recommendations included introducing reward systems; improving incident reporting systems, by for instance implementing a variety of reporting channels and ensuring reporter anonymity; and creating a strong safety culture. Conclusions The barriers to and factors facilitating incident reporting include various organizational and individual factors. As an important way to address these challenging issues and to improve the incident reporting systems in hospitals, we suggest several feasible methods of doing so. PMID:23346479

  18. A microfluidic in vitro system for the quantitative study of the stomach mucus barrier function.

    PubMed

    Li, Leon; Lieleg, Oliver; Jang, Sae; Ribbeck, Katharina; Han, Jongyoon

    2012-10-21

    In the stomach, a layer of gastric mucus protects the epithelial cells of the stomach wall against damage by the acidic digestive juices in the gastric lumen. Despite considerable research, the biophysical mechanisms for this acid barrier are not understood. We present an in vitro microfluidic tool to characterize the stomach acid barrier, in which purified mucin polymers are "secreted" against an acidic zone on chip, mimicking the in vivo secretion of gastric mucus into an acidic stomach lumen. This device reconstitutes both the H(+) concentration gradient and outward flow environment of the mucus layer in vivo. Our experiments demonstrate that a continuously secreted mucin layer hinders acid diffusion, suggesting novel insights into the barrier role of mucins. More broadly, our system may serve as a platform tool for studying the barrier functions provided by mucus layers in the body and for studying mucus drug interactions.

  19. A review of multifunctional nanoemulsion systems to overcome oral and CNS drug delivery barriers.

    PubMed

    Ganta, Srinivas; Deshpande, Dipti; Korde, Anisha; Amiji, Mansoor

    2010-10-01

    The oral and central nervous systems (CNS) present a unique set of barriers to the delivery of important diagnostic and therapeutic agents. Extensive research over the past few years has enabled a better understanding of these physical and biological barriers based on tight cellular junctions and expression of active transporters and metabolizing enzymes at the luminal surfaces of the gastrointestinal (GI) tract and the blood-brain barrier (BBB). This review focuses on the recent understanding of transport across the GI tract and BBB and the development of nanotechnology-based delivery strategies that can enhance bioavailability of drugs. Multifunctional lipid nanosystems, such as oil-in-water nanoemulsions, that integrate enhancement in permeability, tissue and cell targeting, imaging, and therapeutic functions are especially promising. Based on strategic choice of edible oils, surfactants and additional surface modifiers, and different types of payloads, rationale design of multifunctional nanoemulsions can serve as a safe and effective delivery vehicle across oral and CNS barriers.

  20. Geologic controls on regional and local erosion rates of three northern Gulf of Mexico barrier-island systems

    USGS Publications Warehouse

    Twitchell, David C.; Flocks, James G.; Pendleton, Elizabeth; Baldwin, Wayne E.

    2013-01-01

    The stratigraphy of sections of three barrier island systems in the northeastern Gulf of Mexico (Apalachicola, Mississippi, and Chandeleur) have been mapped using geophysical and coring techniques to assess the influence of geologic variations in barrier lithosomes and adjoining inner shelf deposits on long-term rates of shoreline change at regional and local scales. Regional scale was addressed by comparing average geologic characteristics of the three areas with mean shoreline-change rates for each area. Regionally, differences in sand volume contained within the part of the barrier lithosome above sea level, sand volume on the inner shelf, and to a lesser extent, sediment grain size correlate with shoreline change rates. Larger sand volumes and coarser grain sizes are found where erosion rates are lower. Local scale was addressed by comparing alongshore variations in barrier island and inner shelf geology with alongshore variations in shoreline change. Locally, long-term shoreline change rates are highest directly shoreward of paleovalleys exposed on the inner shelf. While geology is not the sole explanation for observed differences in shoreline change along these three coastal regions, it is a significant contributor to change variability.

  1. Multimodality MRI assessment of grey and white matter injury and blood-brain barrier disruption after intracerebral haemorrhage in mice

    PubMed Central

    Yang, Jie; Li, Qian; Wang, Zhongyu; Qi, Cunfang; Han, Xiaoning; Lan, Xi; Wan, Jieru; Wang, Wenzhu; Zhao, Xiaochun; Hou, Zhipeng; Gao, Cong; Carhuapoma, J. Ricardo; Mori, Susumu; Zhang, Jiangyang; Wang, Jian

    2017-01-01

    In this study, we examined injury progression after intracerebral haemorrhage (ICH) induced by collagenase in mice using a preclinical 11.7 Tesla MRI system. On T2-weighted MRI, lesion and striatal volumes were increased on day 3 and then decreased from days 7 to 28. On day 3, with an increase in striatal water content, vasogenic oedema in the perihaematomal region presented as increased T2 and increased apparent diffusion coefficient (ADC) signal. With a synchronous change in T2 and ADC signals, microglial activation peaked on day 3 in the same region and decreased over time. Iron deposition appeared on day 3 around the haematoma border but did not change synchronously with ADC signals. Vascular permeability measured by Evans blue extravasation on days 1, 3, and 7 correlated with the T1-gadolinium results, both of which peaked on day 3. On diffusion tensor imaging, white matter injury was prominent in the corpus callosum and internal capsule on day 3 and then partially recovered over time. Our results indicate that the evolution of grey/white matter injury and blood-brain barrier disruption after ICH can be assessed with multimodal MRI, and that perihaematomal vasogenic oedema might be attributable to microglial activation, iron deposition, and blood-brain barrier breakdown. PMID:28084426

  2. Facilitators and Barriers of Implementing a Measurement Feedback System in Public Youth Mental Health.

    PubMed

    Kotte, Amelia; Hill, Kaitlin A; Mah, Albert C; Korathu-Larson, Priya A; Au, Janelle R; Izmirian, Sonia; Keir, Scott S; Nakamura, Brad J; Higa-McMillan, Charmaine K

    2016-11-01

    This study examines implementation facilitators and barriers of a statewide roll-out of a measurement feedback system (MFS) in a youth public mental health system. 76 % of all state care coordinators (N = 47) completed interviews, which were coded via content analysis until saturation. Facilitators (e.g., recognition of the MFS's clinical utility) and barriers (e.g., MFS's reliability and validity) emerged paralleling the Exploration, Adoption/Preparation, Implementation, and Sustainment framework outlined by Aarons et al. (Adm Policy Mental Health Mental Health Serv Res, 38:4-23, 2011). Sustainment efforts may leverage innovation fit, individual adopter, and system related facilitators.

  3. Building a dedicated information barrier system for warhead and sensitive item verification

    SciTech Connect

    ZUHOSKI,P.B.; INDUSI,J.P.; VANIER,P.E.

    1999-07-25

    This paper documents the development of a dedicated information barrier system for warhead and sensitive item verification. The system the authors describe includes software and hardware information barriers used in conjunction with suitable procedures (or protocols) to achieve a high quality verification while minimizing intrusiveness and preventing transfer of sensitive data to inspectors. The system they describe has been referred to as CIVET--Controlled Intrusiveness Verification Technology and has been implemented to verify warheads and warhead components during various exercises and demonstrations under the auspices of the Department of Energy (DOE) and the Department of Defense (DOD).

  4. The headwinds/tailwinds asymmetry: An availability bias in assessments of barriers and blessings.

    PubMed

    Davidai, Shai; Gilovich, Thomas

    2016-12-01

    Seven studies provide evidence of an availability bias in people's assessments of the benefits they've enjoyed and the barriers they've faced. Barriers and hindrances command attention because they have to be overcome; benefits and resources can often be simply enjoyed and largely ignored. As a result of this "headwind/tailwind" asymmetry, Democrats and Republicans both claim that the electoral map works against them (Study 1), football fans take disproportionate note of the challenging games on their team's schedules (Study 2), people tend to believe that their parents have been harder on them than their siblings are willing to grant (Study 3), and academics think that they have a harder time with journal reviewers, grant panels, and tenure committees than members of other subdisciplines (Study 7). We show that these effects are the result of the enhanced availability of people's challenges and difficulties (Studies 4 and 5) and are not simply the result of self-serving attribution management (Studies 6 and 7). We also show that the greater salience of a person's headwinds can lead people to believe they have been treated unfairly and, as a consequence, more inclined to endorse morally questionable behavior (Study 7). Our discussion focuses on the implications of the headwind/tailwind asymmetry for a variety of ill-conceived policy decisions. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  5. Astrocytic TYMP and VEGFA drive blood–brain barrier opening in inflammatory central nervous system lesions

    PubMed Central

    Chapouly, Candice; Tadesse Argaw, Azeb; Horng, Sam; Castro, Kamilah; Zhang, Jingya; Asp, Linnea; Loo, Hannah; Laitman, Benjamin M.; Mariani, John N.; Straus Farber, Rebecca; Zaslavsky, Elena; Nudelman, German; Raine, Cedric S.

    2015-01-01

    In inflammatory central nervous system conditions such as multiple sclerosis, breakdown of the blood–brain barrier is a key event in lesion pathogenesis, predisposing to oedema, excitotoxicity, and ingress of plasma proteins and inflammatory cells. Recently, we showed that reactive astrocytes drive blood–brain barrier opening, via production of vascular endothelial growth factor A (VEGFA). Here, we now identify thymidine phosphorylase (TYMP; previously known as endothelial cell growth factor 1, ECGF1) as a second key astrocyte-derived permeability factor, which interacts with VEGFA to induce blood–brain barrier disruption. The two are co-induced NFκB1-dependently in human astrocytes by the cytokine interleukin 1 beta (IL1B), and inactivation of Vegfa in vivo potentiates TYMP induction. In human central nervous system microvascular endothelial cells, VEGFA and the TYMP product 2-deoxy-d-ribose cooperatively repress tight junction proteins, driving permeability. Notably, this response represents part of a wider pattern of endothelial plasticity: 2-deoxy-d-ribose and VEGFA produce transcriptional programs encompassing angiogenic and permeability genes, and together regulate a third unique cohort. Functionally, each promotes proliferation and viability, and they cooperatively drive motility and angiogenesis. Importantly, introduction of either into mouse cortex promotes blood–brain barrier breakdown, and together they induce severe barrier disruption. In the multiple sclerosis model experimental autoimmune encephalitis, TYMP and VEGFA co-localize to reactive astrocytes, and correlate with blood–brain barrier permeability. Critically, blockade of either reduces neurologic deficit, blood–brain barrier disruption and pathology, and inhibiting both in combination enhances tissue preservation. Suggesting importance in human disease, TYMP and VEGFA both localize to reactive astrocytes in multiple sclerosis lesion samples. Collectively, these data identify TYMP

  6. Health impact assessment: assessing opportunities and barriers to intersectoral health improvement in an expanded European Union

    PubMed Central

    Lock, K.; McKee, M.

    2005-01-01

    On 1 May 2004 the European Union (EU) underwent unprecedented enlargement, from 15 to 25 countries, increasing its population by 20% to over 450 million. Although EU law has limited specific competence in the area of health, its influence on other policy sectors such as agriculture, trade, and employment has wide ranging implications for health. Yet with the exception of provisions on communicable disease control and food safety, public health considerations have played little part in negotiations on EU accession. This paper argues for an intersectoral public health approach in the expanded EU. It reviews the legal basis for assessing the health impacts of policy in the EU and, using health impact assessment as a case study, it examines how well the new member states may be prepared to tackle intersectoral public health action within the constraints imposed by EU policy. PMID:15831682

  7. Cyclic Failure Mechanisms of Thermal and Environmental Barrier Coating Systems Under Thermal Gradient Test Conditions

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Lee, Kang N.; Miller, Robert A.

    2002-01-01

    Plasma-sprayed ZrO2-8wt%Y2O3 and mullite+BSAS/Si multilayer thermal and environmental barrier coating (TBC-EBC) systems on SiC/SiC ceramic matrix composite (CMC) substrates were thermally cyclic tested under high thermal gradients using a laser high-heat-flux rig in conjunction with furnace exposure in water-vapor environments. Coating sintering and interface damage were assessed by monitoring the real-time thermal conductivity changes during the laser heat-flux tests and by examining the microstructural changes after exposure. Sintering kinetics of the coating systems were also independently characterized using a dilatometer. It was found that the coating failure involved both the time-temperature dependent sintering and the cycle frequency dependent cyclic fatigue processes. The water vapor environments not only facilitated the initial coating conductivity increases due to enhanced sintering and interface reaction, but also promoted later conductivity reductions due to the accelerated coating cracking and delamination. The failure mechanisms of the coating systems are also discussed based on the cyclic test results and are correlated to the sintering and thermal stress behavior under the thermal gradient test conditions.

  8. Methodologies to assess drug permeation through the blood-brain barrier for pharmaceutical research.

    PubMed

    Passeleu-Le Bourdonnec, Céline; Carrupt, Pierre-Alain; Scherrmann, Jean Michel; Martel, Sophie

    2013-11-01

    The drug discovery process for drugs that target the central nervous system suffers from a very high rate of failure due to the presence of the blood-brain barrier, which limits the entry of xenobiotics into the brain. To minimise drug failure at different stages of the drug development process, new methodologies have been developed to understand the absorption, distribution, metabolism, excretion and toxicity (ADMET) profile of drug candidates at early stages of drug development. Additionally, understanding the permeation of drug candidates is also important, particularly for drugs that target the central nervous system. During the first stages of the drug discovery process, in vitro methods that allow for the determination of permeability using high-throughput screening methods are advantageous. For example, performing the parallel artificial membrane permeability assay followed by cell-based models with interesting hits is a useful technique for identifying potential drugs. In silico models also provide interesting information but must be confirmed by in vitro models. Finally, in vivo models, such as in situ brain perfusion, should be studied to reduce a large number of drug candidates to a few lead compounds. This article reviews the different methodologies used in the drug discovery and drug development processes to determine the permeation of drug candidates through the blood-brain barrier.

  9. The Development of HfO2-Rare Earth Based Oxide Materials and Barrier Coatings for Thermal Protection Systems

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Harder, Bryan James

    2014-01-01

    Advanced hafnia-rare earth oxides, rare earth aluminates and silicates have been developed for thermal environmental barrier systems for aerospace propulsion engine and thermal protection applications. The high temperature stability, low thermal conductivity, excellent oxidation resistance and mechanical properties of these oxide material systems make them attractive and potentially viable for thermal protection systems. This paper will focus on the development of the high performance and high temperature capable ZrO2HfO2-rare earth based alloy and compound oxide materials, processed as protective coating systems using state-or-the-art processing techniques. The emphasis has been in particular placed on assessing their temperature capability, stability and suitability for advanced space vehicle entry thermal protection systems. Fundamental thermophysical and thermomechanical properties of the material systems have been investigated at high temperatures. Laser high-heat-flux testing has also been developed to validate the material systems, and demonstrating durability under space entry high heat flux conditions.

  10. Effect of joint mechanism on vehicle redirectional capability of water-filled road safety barrier systems.

    PubMed

    Thiyahuddin, M I; Thambiratnam, D P; Gu, Y T

    2014-10-01

    Portable water-filled barriers (PWFBs) are roadside appurtenances that prevent vehicles from penetrating into temporary construction zones on roadways. PWFBs are required to satisfy the strict regulations for vehicle re-direction in tests. However, many of the current PWFBs fail to re-direct the vehicle at high speeds due to the inability of the joints to provide appropriate stiffness. The joint mechanism hence plays a crucial role in the performance of a PWFB system at high speed impacts. This paper investigates the desired features of the joint mechanism in a PWFB system that can re-direct vehicles at high speeds, while limiting the lateral displacement to acceptable limits. A rectangular "wall" representative of a 30m long barrier system was modeled and a novel method of joining adjacent road barriers was introduced through appropriate pin-joint connections. The impact response of the barrier "wall" and the vehicle was obtained and the results show that a rotational stiffness of 3000kNm/rad at the joints seems to provide the desired features of the PWFB system to re-direct impacting vehicles and restrict the lateral deflection. These research findings will be useful to safety engineers and road barrier designers in developing a new generation of PWFBs for increased road safety.

  11. Microwave life-detection systems for searching human subjects under earthquake rubble or behind barrier.

    PubMed

    Chen, K M; Huang, Y; Zhang, J; Norman, A

    2000-01-01

    A new sensitive microwave life-detection system which can be used to locate human subjects buried under earthquake rubble or hidden behind various barriers has been constructed. This system operating at 1150 MHz or 450 MHz can detect the breathing and heartbeat signals of human subjects through an earthquake rubble or a construction barrier of about 10-ft thickness. The basic physical principle for the operation of a microwave life-detection system is rather simple. When a microwave beam of appropriate frequency (L or S band) is aimed at a pile of earthquake rubble covering a human subject or illuminated through a barrier obstructing a human subject, the microwave beam can penetrate the rubble or the barrier to reach the human subject. When the human subject is illuminated by a microwave beam, the reflected wave from the human subject will be modulated by the subject's body movements, which include the breathing and the heartbeat. If the clutter consisting of the reflected wave from stationary background can be completely eliminated and the reflected wave from the human subject's body is properly modulated, the breathing and heartbeat signals of the subject can be extracted. Thus, a human subject buried under earthquake rubble or hidden behind barriers can be located. This system has been tested extensively in a simulated earthquake rubble in the laboratory and also in a field test using realistic earthquake rubble conducted by a Federal Emergency Management Agency (FEMA) Task Force.

  12. Risk analysis of the governance system affecting outcomes in the Great Barrier Reef.

    PubMed

    Dale, Allan P; Vella, Karen; Pressey, Robert L; Brodie, Jon; Gooch, Margaret; Potts, Ruth; Eberhard, Rachel

    2016-12-01

    The state and trend of the Great Barrier Reef's (GBR's) ecological health remains problematic, influencing United Nations Educational, Scientific and Cultural Organization (UNESCO) statements regarding GBR governance. While UNESCO's concerns triggered separate strategic assessments by the Australian and Queensland governments, there has been no independent and integrated review of the key risks within the overall system of governance influencing GBR outcomes. As a case study of international significance, this paper applies Governance Systems Analysis (GSA), a novel analytical framework that identifies the governance themes, domains and subdomains most likely to influence environmental and socio-economic outcomes in complex natural systems. This GBR-focussed application of GSA identifies governance subdomains that present high, medium, or low risk of failure to produce positive outcomes for the Reef. This enabled us to determine that three "whole of system" governance problems could undermine GBR outcomes. First, we stress the integrative importance of the Long Term Sustainability Plan (LTSP) Subdomain. Sponsored by the Australian and Queensland governments, this subdomain concerns the primary institutional arrangements for coordinated GBR planning and delivery, but due to its recent emergence, it faces several internal governance challenges. Second, we find a major risk of implementation failure in the achievement of GBR water quality actions due to a lack of system-wide focus on building strong and stable delivery systems at catchment scale. Finally, we conclude that the LTSP Subdomain currently has too limited a mandate/capacity to influence several high-risk subdomains that have not been, but must be more strongly aligned with Reef management (e.g. the Greenhouse Gas Emission Management Subdomain). Our analysis enables exploration of governance system reforms needed to address environmental trends in the GBR and reflects on the potential application of GSA in

  13. 7 CFR 1955.56 - Real property located in Coastal Barrier Resources System (CBRS).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... System (CBRS). 1955.56 Section 1955.56 Agriculture Regulations of the Department of Agriculture... Management of Property § 1955.56 Real property located in Coastal Barrier Resources System (CBRS). (a... within a CBRS where: (1) The action goes beyond maintenance, replacement-in-kind, reconstruction, or...

  14. 7 CFR 1955.56 - Real property located in Coastal Barrier Resources System (CBRS).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... System (CBRS). 1955.56 Section 1955.56 Agriculture Regulations of the Department of Agriculture... Management of Property § 1955.56 Real property located in Coastal Barrier Resources System (CBRS). (a... within a CBRS where: (1) The action goes beyond maintenance, replacement-in-kind, reconstruction, or...

  15. 7 CFR 1955.56 - Real property located in Coastal Barrier Resources System (CBRS).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... System (CBRS). 1955.56 Section 1955.56 Agriculture Regulations of the Department of Agriculture... Management of Property § 1955.56 Real property located in Coastal Barrier Resources System (CBRS). (a... within a CBRS where: (1) The action goes beyond maintenance, replacement-in-kind, reconstruction, or...

  16. 7 CFR 1955.56 - Real property located in Coastal Barrier Resources System (CBRS).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... System (CBRS). 1955.56 Section 1955.56 Agriculture Regulations of the Department of Agriculture... Management of Property § 1955.56 Real property located in Coastal Barrier Resources System (CBRS). (a... within a CBRS where: (1) The action goes beyond maintenance, replacement-in-kind, reconstruction, or...

  17. 7 CFR 1955.56 - Real property located in Coastal Barrier Resources System (CBRS).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... System (CBRS). 1955.56 Section 1955.56 Agriculture Regulations of the Department of Agriculture... Management of Property § 1955.56 Real property located in Coastal Barrier Resources System (CBRS). (a... within a CBRS where: (1) The action goes beyond maintenance, replacement-in-kind, reconstruction, or...

  18. Application of GPR, EMI, and Lidar to Assess the Role of Antecedent Geology in Barrier Island Evolution

    NASA Astrophysics Data System (ADS)

    Wernette, P. A.; Weymer, B. A.; Houser, C.; Bishop, M. P.; Everett, M. E.

    2014-12-01

    Barrier island longevity is threatened by the observed and modeled accelerating rates of sea-level rise. It has been suggested that subsurface geologic structure is also an important factor controlling barrier island morphology and long-term island evolution, yet the precise role of antecedent geology on the response and recovery of barrier islands to hurricanes and sea-level rise remains unclear. Thus, this study aims to provide more detailed insight into the role of the antecedent geology on barrier island evolution at two sites along the Texas, USA coast: Follets Island and a portion of North Padre Island. Alongshore and across-island ground-penetrating radar (GPR) and electromagnetic inductance (EMI) surveys are used in this study to infer subsurface geologic structure. The accuracy of the interpreted geophysical survey data was assessed using selective vibracoring. Information about island morphology is derived from airborne and terrestrial LiDAR-derived digital elevation models (DEMs). Preliminary results suggest that dune height is generally lower and washover frequency higher in areas where the antecedent geologic surface is deeper. Another important factor influencing dune breaching and washover locations is offshore bathymetry. The barrier island is generally narrower in areas where an offshore swale is present. The antecedent geologic structure is an important factor influencing barrier island morphology. Integrating EMI, GPR, and seismic subsurface geologic structure information and surficial morphology information helps improve our understanding of factors affecting barrier island evolution and the role that antecedent geology plays in island morphology.

  19. Physical connectivity in the Mesoamerican Barrier Reef System inferred from 9 years of ocean color observations

    NASA Astrophysics Data System (ADS)

    Soto, I.; Andréfouët, S.; Hu, C.; Muller-Karger, F. E.; Wall, C. C.; Sheng, J.; Hatcher, B. G.

    2009-06-01

    Ocean color images acquired from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) from 1998 to 2006 were used to examine the patterns of physical connectivity between land and reefs, and among reefs in the Mesoamerican Barrier Reef System (MBRS) in the northwestern Caribbean Sea. Connectivity was inferred by tracking surface water features in weekly climatologies and a time series of weekly mean chlorophyll- a concentrations derived from satellite imagery. Frequency of spatial connections between 17 pre-defined, geomorphological domains that include the major reefs in the MBRS and river deltas in Honduras and Nicaragua were recorded and tabulated as percentage of connections. The 9-year time series of 466 weekly mean images portrays clearly the seasonal patterns of connectivity, including river plumes and transitions in the aftermath of perturbations such as hurricanes. River plumes extended offshore from the Honduras coast to the Bay Islands (Utila, Cayo Cochinos, Guanaja, and Roatán) in 70% of the weekly mean images. Belizean reefs, especially those in the southern section of the barrier reef and Glovers Atoll, were also affected by riverine discharges in every one of the 9 years. Glovers Atoll was exposed to river plumes originating in Honduras 104/466 times (22%) during this period. Plumes from eastern Honduras went as far as Banco Chinchorro and Cozumel in Mexico. Chinchorro appeared to be more frequently connected to Turneffe Atoll and Honduran rivers than with Glovers and Lighthouse Atolls, despite their geographic proximity. This new satellite data analysis provides long-term, quantitative assessments of the main pathways of connectivity in the region. The percentage of connections can be used to validate predictions made using other approaches such as numerical modeling, and provides valuable information to ecosystem-based management in coral reef provinces.

  20. Overcoming Barriers to Educational Restructuring: A Call for System Literacy.

    ERIC Educational Resources Information Center

    McGonagill, Grady

    The drive for systemic reform in education reflects a widespread hunger in all sectors of society to make sense of the whole, as is shown in the increasing recognition of people in organizations of the interrelatedness of the organizations' parts. However, many attempts at systemic reform are hampered by the lack of a common view of what an…

  1. Advanced thermal barrier coating system development: Technical progress report

    SciTech Connect

    1996-08-07

    Objectives are to provide an improved TBC system with increased temperature capability and improved reliability, for the Advanced Turbine Systems program (gas turbine). The base program consists of three phases: Phase I, program planning (complete); Phase II, development; and Phase III (selected specimen-bench test). Work is currently being performed in Phase II.

  2. Matched Bipartite Digraph Representation of Generalized Dynamical System Formed by One-way Barriers

    NASA Astrophysics Data System (ADS)

    Li, John; Mahoney, John; Mitchell, Kevin; Tom Solomon Collaboration

    2014-03-01

    We studied a dynamical system with stable and unstable manifolds that behave as one-way barriers, instead of separatrices in traditional dynamical system that are two-way barriers. This asymmetry gives rise to a richer dynamical behavior such as the overlapping of basins of attraction. The recently developed Burning Invariant Manifold (BIM) theory took a dynamical system approach to understand front propagation in Advection-Reaction-Diffusion systems, which have BIMs as the one-way barriers. Through numerical simulations under BIM theory, we found that although both unstable and stable BIMs are one-way barriers, unstable BIMs are the ones that we can experimentally observe the fronts converging onto, and the stable BIMs act as the basin boundaries. We further hypothesized a duality relation between the stable and unstable BIMs. Under the duality hypothesis, we developed a mechanism of the behavior of the system by reducing it back to a traditional system based on topology, and we found a simplification of the system by to summarize the topological information into a Matched Bipartite directed graph (MB digraph). This work was supported by the US National Science Foundation under grant PHY-0748828 and NSF Fellowship DGE-0937362.

  3. 3D vision system assessment

    NASA Astrophysics Data System (ADS)

    Pezzaniti, J. Larry; Edmondson, Richard; Vaden, Justin; Hyatt, Bryan; Chenault, David B.; Kingston, David; Geulen, Vanilynmae; Newell, Scott; Pettijohn, Brad

    2009-02-01

    In this paper, we report on the development of a 3D vision system consisting of a flat panel stereoscopic display and auto-converging stereo camera and an assessment of the system's use for robotic driving, manipulation, and surveillance operations. The 3D vision system was integrated onto a Talon Robot and Operator Control Unit (OCU) such that direct comparisons of the performance of a number of test subjects using 2D and 3D vision systems were possible. A number of representative scenarios were developed to determine which tasks benefited most from the added depth perception and to understand when the 3D vision system hindered understanding of the scene. Two tests were conducted at Fort Leonard Wood, MO with noncommissioned officers ranked Staff Sergeant and Sergeant First Class. The scenarios; the test planning, approach and protocols; the data analysis; and the resulting performance assessment of the 3D vision system are reported.

  4. Thermal Performance Evaluation of Attic Radiant Barrier Systems Using the Large Scale Climate Simulator (LSCS)

    SciTech Connect

    Shrestha, Som S; Miller, William A; Desjarlais, Andre Omer

    2013-01-01

    Application of radiant barriers and low-emittance surface coatings in residential building attics can significantly reduce conditioning loads from heat flow through attic floors. The roofing industry has been developing and using various radiant barrier systems and low-emittance surface coatings to increase energy efficiency in buildings; however, minimal data are available that quantifies the effectiveness of these technologies. This study evaluates performance of various attic radiant barrier systems under simulated summer daytime conditions and nighttime or low solar gain daytime winter conditions using the large scale climate simulator (LSCS). The four attic configurations that were evaluated are 1) no radiant barrier (control), 2) perforated low-e foil laminated oriented strand board (OSB) deck, 3) low-e foil stapled on rafters, and 4) liquid applied low-emittance coating on roof deck and rafters. All test attics used nominal RUS 13 h-ft2- F/Btu (RSI 2.29 m2-K/W) fiberglass batt insulation on attic floor. Results indicate that the three systems with radiant barriers had heat flows through the attic floor during summer daytime condition that were 33%, 50%, and 19% lower than the control, respectively.

  5. In vitro assessment of alkylglyceryl-functionalized chitosan nanoparticles as permeating vectors for the blood-brain barrier.

    PubMed

    Lien, Chun-Fu; Molnár, Eva; Toman, Petr; Tsibouklis, John; Pilkington, Geoffrey J; Górecki, Dariusz C; Barbu, Eugen

    2012-04-09

    A series of O-substituted alkylglyceryl chitosans with systematically varied alkyl chain length and degree of grafting has been employed for the formulation of aqueous nanoparticulate systems, which were in turn investigated for their effects on a modeled blood-brain-barrier system of mouse-brain endothelial cells. Barrier function measurements employing electric cell-substrate impedance sensing and analyses of tight junction-specific protein profiles have indicated that the alkylglyceryl-modified chitosan nanoparticles impact upon the integrity of the model blood-brain barrier, whereas confocal microscopy experiments have demonstrated the efficient cellular uptake and the perinuclear localization of these nanoparticles. The application of nanoparticles to the model blood-brain barrier effected an increase in its permeability, as demonstrated by following the transport of the tracer molecule fluorescein isothiocyanate.

  6. Experimental and Theoretical Assessment of the Lifetime of a Gaseous-Reduced Vadose Zone Permeable Reactive Barrier

    SciTech Connect

    Thornton, Edward C.; Zhong, Lirong; Oostrom, Mart; Deng, Baolin

    2007-11-20

    The feasibility of using gaseous reduction to establish a vadose zone permeable reactive barrier was evaluated through a combination of laboratory testing activities and consideration of fundamental vadose zone transport concepts. For the experimental evaluation, a series of laboratory column tests were conducted in which sediment was first treated with diluted hydrogen sulfide. Water containing dissolved oxygen was then pumped through the columns at different flow rates to determine the reoxidation rate and the reductive capacity of the treated sediment. The results indicated that the treated sediment has a significant reductive capacity consistent with the basic reactions associated with the treatment and reoxidation processes. The observed reductive capacity was found to be dependent on the flow rate of water during the reoxidation phase of the tests. At lower flow rates, the reductive capacity approached the maximum value predicted on the basis of the treatment reaction. Thus, laboratory treatment tests should reliably predict the reductive capacity of the barrier under field conditions. A theoretical approach was undertaken to estimate the lifetime of the vadose zone barrier. An initial model assumed that the barrier lifetime is determined by the reoxidation of the barrier owing to the transport of oxygen through a vadose zone interval in which all sediment is unsaturated. The results of this evaluation suggest that barrier reoxidation is primarily related to diffusion of oxygen through the gas-filled portion of the sediment pore space. If so, the barrier lifetime could be fairly short (several years). However, the presence of finer grained strata with higher moisture content could potentially increase the barrier lifetime to 100 years or more owing to a decrease in the effective diffusion coefficient for oxygen. Thus, detailed stratagraphic characterization and modeling is needed to provide an accurate assessment of barrier lifetime at specific sites.

  7. Spatiotemporal variability of sedimentology and morphology in the East Frisian barrier island system

    NASA Astrophysics Data System (ADS)

    Herrling, Gerald; Winter, Christian

    2017-04-01

    The highly dynamic East Frisian barrier island system (southern North Sea) is characterized by a complex morphology of tidal inlets, ebb-tidal deltas and foreshore beaches that reacts to storms and fair-weather conditions with characteristic patterns of sediment grain-size distributions. The morphological and sedimentological response to varying hydrodynamic conditions yet occurs in short time spans that are not covered by common monitoring strategies with measuring intervals typically of years. This study applies process-based numerical modelling with multiple sediment fractions to interpolate morphological states in time between bathymetrical surveys conducted in the summer months of 2004 and 2006. Morphodynamic simulations driven by real-time boundary conditions of tides, wind and waves are carried out for a representative period of 2 years. The spatiotemporal variability of the nearshore sedimentology and morphology is assessed by graded ranges of bed dynamics (i.e. bed elevation range) and the definition of sediment grain-size variability (i.e. mean diameter range). The effect of storm events and timescales of the sedimentological adaptation after storms to typical fair-weather conditions are exemplified at an ebb-tidal delta lobe where the morphological and sedimentological variability is found to be largest in the study area. The proposed method may serve to identify areas of high sedimentological and morphological activity for system understanding or in the framework of coastal monitoring strategies.

  8. Spatiotemporal variability of sedimentology and morphology in the East Frisian barrier island system

    NASA Astrophysics Data System (ADS)

    Herrling, Gerald; Winter, Christian

    2016-08-01

    The highly dynamic East Frisian barrier island system (southern North Sea) is characterized by a complex morphology of tidal inlets, ebb-tidal deltas and foreshore beaches that reacts to storms and fair-weather conditions with characteristic patterns of sediment grain-size distributions. The morphological and sedimentological response to varying hydrodynamic conditions yet occurs in short time spans that are not covered by common monitoring strategies with measuring intervals typically of years. This study applies process-based numerical modelling with multiple sediment fractions to interpolate morphological states in time between bathymetrical surveys conducted in the summer months of 2004 and 2006. Morphodynamic simulations driven by real-time boundary conditions of tides, wind and waves are carried out for a representative period of 2 years. The spatiotemporal variability of the nearshore sedimentology and morphology is assessed by graded ranges of bed dynamics (i.e. bed elevation range) and the definition of sediment grain-size variability (i.e. mean diameter range). The effect of storm events and timescales of the sedimentological adaptation after storms to typical fair-weather conditions are exemplified at an ebb-tidal delta lobe where the morphological and sedimentological variability is found to be largest in the study area. The proposed method may serve to identify areas of high sedimentological and morphological activity for system understanding or in the framework of coastal monitoring strategies.

  9. Access to Vocational Education. A Planning System for Local Secondary and Post-Secondary Program and Facility Accessibility. Step 1: Identifying Barriers.

    ERIC Educational Resources Information Center

    Rice, Eric; And Others

    This guidebook focuses on the first of five steps included in a planning system for improving local secondary and postsecondary program and facilities accessibility: identifying barriers. The first five sections of the booklet are comprised of self-instructional descriptions of five needs-assessment procedures that can be used to identify…

  10. Barrier distribution functions for the system 6Li+64Ni and the effect of channel coupling

    NASA Astrophysics Data System (ADS)

    Shaikh, Md. Moin; Roy, Subinit; Rajbanshi, S.; Pradhan, M. K.; Mukherjee, A.; Basu, P.; Pal, S.; Nanal, V.; Pillay, R. G.; Shrivastava, A.

    2015-03-01

    Background: The barrier distribution function is an important observable in low-energy nucleus-nucleus collisions because it carries the distinct signature of the channel-coupling effect that is dominant at low energies. It can be derived from the fusion excitation function as well as from the back-angle quasi-elastic excitation function. The barrier distribution functions derived from the two complimentary measurements, in general, appear to peak at an energy close to the Coulomb barrier for strongly bound systems. But for weakly bound projectiles, like 6Li, a relative shift is observed between the distributions. Purpose: The present work investigates the barrier distribution functions from fusion as well as from the back-angle quasi-elastic excitation function for the 6Li+64Ni system. The purpose is to look for the existence of a shift, if any, between the two measured distribution functions, as reported for 6Li collision with heavy targets. A detailed coupled-channel calculation to probe the behavior of the distribution functions and their relative shift has been attempted. Measurement: A simultaneous measurement of fusion and back-angle quasi-elastic excitation functions for the system 6Li+64Ni was performed. The fusion excitation function was measured for the energy range of 11 to 28 MeV while the quasi-elastic excitation function measurement extended from 11 to 20 MeV. The barrier distribution functions were subsequently extracted from both the excitation functions and compared. Results: A small shift of around 450 keV peak to peak is observed between the barrier distribution functions derived from the complementary measurements. Detailed coupled channel and coupled reaction channel calculations reproduced both the excitation functions and barrier distributions. The shift of about 550 keV resulted from the model predictions corroborate the experimentally observed value for 6Li+64Ni system. Conclusions: The coupling to inelastic channels are found to be

  11. Advanced thermal barrier coating system development. Technical progress report

    SciTech Connect

    1996-06-10

    The objectives of the program are to provide an improved TBC system with increased temperature capability and improved reliability relative to current state of the art TBC systems. The development of such a coating system is essential to the ATS engine meeting its objectives. The base program consists of three phases: Phase 1: Program Planning--Complete; Phase 2: Development; Phase 3: Selected Specimen--Bench Test. Work is currently being performed in Phase 2 of the program. In Phase 2, process improvements will be married with new bond coat and ceramic materials systems to provide improvements over currently available TBC systems. Coating reliability will be further improved with the development of an improved lifing model and NDE techniques. This will be accomplished by conducting the following program tasks: II.1 Process Modeling; II.2 Bond Coat Development; II.3 Analytical Lifing Model; II.4 Process Development; II.5 NDE, Maintenance and Repair; II.6 New TBC Concepts. A brief summary is given of progress made in each of these 6 areas.

  12. Barriers to Excellence: The Culture of Silence in School Systems.

    ERIC Educational Resources Information Center

    Rusch, Edith A.

    Little is known about how restructuring networks actually affect the cultures of school systems. This report examines the creation of an "island" of reform in a school district in northwest Ohio. The research emanated from the discovery of a new "island" in northwest Ohio called the Pathfinder Network. The group formed through…

  13. Method of in situ retrieval of contaminants or other substances using a barrier system and leaching solutions

    SciTech Connect

    Nickelson, Reva A.; Walsh, Stephanie; Richardson, John G.; Dick, John R.; Sloan, Paul A.

    2006-12-26

    Processes and methods relating to treating contaminants and collecting desired substances from a zone of interest using subterranean collection and containment barriers. Tubular casings having interlock structures are used to create subterranean barriers for containing and treating buried waste and its effluents. The subterranean barrier includes an effluent collection system. Treatment solutions provided to the zone of interest pass therethrough and are collected by the barrier and treated or recovered, allowing on-site remediation. Barrier components may be used to in the treatment by collecting or removing contaminants or other materials from the zone of interest.

  14. Modeling the Hydrogeochemical Transport of Radionuclides through Engineered Barriers System in the Proposed LLW Disposal Site of Taiwan - 12082

    SciTech Connect

    Lin, Wen-Sheng; Liu, Chen-Wuing; Tsao, Jui-Hsuan; Li, Ming-Hsu

    2012-07-01

    A proposed site for final disposal of low-level radioactive waste located in Daren Township of Taitung County along the southeastern coast has been on the selected list in Taiwan. The geology of the Daren site consists of argillite and meta-sedimentary rocks. A mined cavern design with a tunnel system of 500 m below the surface is proposed. Concrete is used as the main confinement material for the engineered barrier. To investigate the hydrogeochemical transport of radionuclides through engineered barriers system, HYDROGEOCHEM5.0 model was applied to simulate the complex chemical interactions among radionuclides, the cement minerals of the concrete, groundwater flow, and transport in the proposed site. The simulation results showed that the engineered barriers system with the side ditch efficiently drained the ground water and lowered the concentration of the concrete degradation induced species (e.g., hydrogen ion, sulfate, and chloride). The velocity of groundwater observed at side ditch gradually decreased with time due to the fouling of pore space by the mineral formation of ettringite and thaumasite. The short half-life of Co-60, Sr-90 and Cs-137 significantly reduced the concentrations, whereas the long half-life of I-129(1.57x10{sup 7} years) and Am-241(432 years) remain stable concentrations at the interface of waste canister and concrete barrier after 300 years. The mineral saturation index (SI) was much less than zero due to the low aqueous concentration of radionuclide, so that the precipitation formation of Co-60, Sr-90, I-129, Cs-137 and Am-241 related minerals were not found. The effect of adsorption/desorption (i.e., surface complexation model) could be a crucial geochemical mechanism for the modeling of liquid-solid phase behavior of radionuclide in geochemically dynamic environments. Moreover, the development of advanced numerical models that are coupled with hydrogeochemical transport and dose assessment of radionuclide is required in the future

  15. The Role of Backbarrier Filling in the Evolution of a Barrier Island System

    NASA Astrophysics Data System (ADS)

    Hein, C. J.; Fitzgerald, D. M.; Stone, B. D.; Carruthers, E.; Gontz, A. M.

    2009-12-01

    Barrier islands develop through a variety of processes, including spit accretion, barrier elongation, breaching and inlet filling. New geophysical and sedimentological data collected along a barrier system in the western Gulf of Maine provide a means of documenting a unique process of barrier evolution involving backbarrier infilling and ensuing closure of an ancient tidal inlet. Plum Island is located along a mixed-energy, tide-dominated coastline bounded by estuaries and backed by an extensive system of salt marsh and tidal creeks. Following the regional glacioisostatic lowstand of approximately -45 m at 12 ka, the Holocene transgression reworked a late Pleistocene regressive braid plain and lowstand delta. Sediments driven onshore during the transgression and derived from the Merrimack River fed the developing barrier system. Radiocarbon dates suggests that backbarrier sands began accumulating at the modern site of Plum Island at approximately 9 ka. At this time, the barrier was composed of several discrete islands separated by inlets and situated offshore of modern Plum Island. Shallow seismic and ground penetrating radar (GPR) data confirm the existence of lower stand riverine/tidal channels extending onto the shallow shelf. Coincident with the slowing of relative sea level rise, Plum Island began to form in its current location approximately 5.5 ka, establishing its modern form by about 2.5 ka. Sediment cores and GPR data demonstrate that the barrier lithosome is 5 to 15 m thick and evolved through initial aggradation followed by southerly spit accretion and progradation. The discovery of a multiple inlet channel system reoccupying the area carved by the lowstand Parker River indicates that central Plum Island underwent a complex developmental history. Cores through the inlet sequence consist of fine to medium sand with repetitive interbedded coarse sand units, marking high-energy depositional events associated with spit accretion and displacement of the

  16. Complexity: A Cognitive Barrier to Defense Systems Acquisition Management

    DTIC Science & Technology

    2001-01-01

    observer’s role was central to America’s preeminent nine- teenth century philosopher, Charles Sand- ers Peirce , who wrote about the triadic relationship...science education even today. The ideas of Boscovich and Peirce re- garding the role of the observer resurfaced with the emergence of systems science...simultaneously is well known (Waller, 1982; Miller, 1956; Simon , 1974; Warfield, 1988). The tendency is to underconceptualize interrelationships, thereby

  17. Implementation of health risk assessments with family health history: barriers and benefits.

    PubMed

    Wu, R Ryanne; Orlando, Lori A

    2015-09-01

    Health risk assessments provide an opportunity to emphasise health promotion and disease prevention for individuals and populations at large. A key component of health risk assessments is the detailed collection of family health history information. This information is helpful in determining risk both for common chronic conditions and more rare diseases as well. While the concept of health risk assessments has been around since the Framingham Heart Study was launched in the 1950s, and such assessments are commonly performed in the workplace today, the US healthcare system has been slow to embrace them and the emphasis on prevention that they represent. Before wider implementation of health risk assessments within healthcare can be seen, several concerns must be addressed: (1) provider impact, (2) patient impact, (3) validity of patient-entered data and (4) health outcomes effect. Here, we describe recent developments in health risk assessment design that are helping to address these issues.

  18. Portable Immune-Assessment System

    NASA Technical Reports Server (NTRS)

    Pierson, Duane L.; Stowe, Raymond P.; Mishra, Saroj K.

    1995-01-01

    Portable immune-assessment system developed for use in rapidly identifying infections or contaminated environment. System combines few specific fluorescent reagents for identifying immune-cell dysfunction, toxic substances, buildup of microbial antigens or microbial growth, and potential identification of pathogenic microorganisms using fluorescent microplate reader linked to laptop computer. By using few specific dyes for cell metabolism, DNA/RNA conjugation, specific enzyme activity, or cell constituents, one makes immediate, onsite determination of person's health or of contamination of environment.

  19. An Activity Theory Approach to Analyze Barriers to a Virtual Management Information Systems (MIS) Curriculum

    ERIC Educational Resources Information Center

    Jaradat, Suhair; Qablan, Ahmad; Barham, Areej

    2011-01-01

    This paper explains how the activity theory is used as a framework to analyze the barriers to a virtual Management Information Stream (MIS) Curriculum in Jordanian schools, from both the sociocultural and pedagogical perspectives. Taking the activity system as a unit of analysis, this study documents the processes by which activities shape and are…

  20. An Activity Theory Approach to Analyze Barriers to a Virtual Management Information Systems (MIS) Curriculum

    ERIC Educational Resources Information Center

    Jaradat, Suhair; Qablan, Ahmad; Barham, Areej

    2011-01-01

    This paper explains how the activity theory is used as a framework to analyze the barriers to a virtual Management Information Stream (MIS) Curriculum in Jordanian schools, from both the sociocultural and pedagogical perspectives. Taking the activity system as a unit of analysis, this study documents the processes by which activities shape and are…

  1. Underutilization of Mental Health Services among College Students: An Examination of System-Related Barriers

    ERIC Educational Resources Information Center

    Marsh, Carey N.; Wilcoxon, S. Allen

    2015-01-01

    Despite the documented benefits of counseling and mental health services on academic performance and degree attainment, only about 10% of psychologically distressed college students ever seek professional help. This investigation examined mental health care system-related barriers that might distinguish help seekers from nonhelp seekers among…

  2. Barriers to Systemic, Effective, and Sustainable Technology Use in High School Classrooms

    ERIC Educational Resources Information Center

    Daniels, Jason Scott; Jacobsen, Michele; Varnhagen, Stanley; Friesen, Sharon

    2013-01-01

    The purpose of the Technology and High School Success (THSS) initiative was to encourage innovative strategies focused on improving provincial high school completion rates, using technology and student-centered learning to engage student interest. The primary purpose of this paper is to report on barriers that impede systemic, effective and…

  3. Underutilization of Mental Health Services among College Students: An Examination of System-Related Barriers

    ERIC Educational Resources Information Center

    Marsh, Carey N.; Wilcoxon, S. Allen

    2015-01-01

    Despite the documented benefits of counseling and mental health services on academic performance and degree attainment, only about 10% of psychologically distressed college students ever seek professional help. This investigation examined mental health care system-related barriers that might distinguish help seekers from nonhelp seekers among…

  4. Advanced thermal barrier system bond coatings for use on Ni, Co-, and Fe-base alloy substrates

    NASA Technical Reports Server (NTRS)

    Stecura, S.

    1985-01-01

    New and improved Ni-, Co-, and Fe-base bond coatings have been identified for the ZrO2-Y2O3 thermal barrier coatings to be used on NI-, Co-, and Fe-base alloy substrates. These bond coatings were evaluated in a cyclic furnace between 1120 and 1175 C. It was found that MCrAlYb (where M = Ni, Co, or Fe) bond coating thermal barrier systems. The longest life was obtained with the FeCrAlYb thermal barrier system followed by NiCrAlYb and CoCrAlYb thermal barrier systems in that order.

  5. The validation of a questionnaire to assess barriers to enteral feeding in critically ill patients: a multicenter international survey

    PubMed Central

    2014-01-01

    Background A growing body of literature supports the need to identify and address barriers to knowledge use as a strategy to improve care delivery. To this end, we developed a questionnaire to assess barriers to enterally feeding critically ill adult patients, and sought to gain evidence to support the construct validity of this instrument by testing the hypothesis that barriers identified by the questionnaire are inversely associated with nutrition performance. Methods We conducted a multilevel multivariable regression analysis of data from an observational study in 55 Intensive Care Units (ICUs) from 5 geographic regions. Data on nutrition practices were abstracted from 1153 patient charts, and 1439 critical care nurses completed the ‘Barriers to Enterally Feeding critically Ill Patients’ questionnaire. Our primary outcome was adequacy of calories from enteral nutrition (proportion of prescribed calories received enterally) and our primary predictor of interest was a barrier score derived from ratings of importance of items in the questionnaire. Results The mean adequacy of calories from enteral nutrition was 48 (Standard Deviation (SD)17)%. Evaluation for confounding identified patient type, proportion of nurse respondents working in the ICU greater than 5 years, and geographic region as important covariates. In a regression model adjusting for these covariates plus evaluable nutrition days and APACHE II score, we observed that a 10 point increase in overall barrier score is associated with a 3.5 (Standard Error (SE)1.3)% decrease in enteral nutrition adequacy (p-values <0.01). Conclusion Our results provide evidence to support our a priori hypothesis that barriers negatively impact the provision of nutrition in ICUs, suggesting that our recently developed questionnaire may be a promising tool to identify these important factors, and guide the selection of interventions to optimize nutrition practice. Further research is required to illuminate if and how

  6. The risk assessment information system

    SciTech Connect

    Kerr, S.B.; Bonczek, R.R.; McGinn, C.W.; Land, M.L.; Bloom, L.D.; Sample, B.E.; Dolislager, F.G.

    1998-06-01

    In an effort to provide service-oriented environmental risk assessment expertise, the Department of Energy (DOE) Center for Risk Excellence (CRE) and DOE Oak Ridge Operations Office (ORO) are sponsoring Oak Ridge National Laboratory (ORNL) to develop a web-based system for disseminating risk tools and information to its users. This system, the Risk Assessment Information System (RAIS), was initially developed to support the site-specific needs of the DOE-ORO Environmental Restoration Risk Assessment Program. With support from the CRE, the system is currently being expanded to benefit all DOE risk information users and can be tailored to meet site-specific needs. Taking advantage of searchable and executable databases, menu-driven queries, and data downloads, using the latest World Wide Web technologies, the RAIS offers essential tools that are used in the risk assessment process or anywhere from project scoping to implementation. The RAIS tools can be located directly at http://risk.lsd.ornl.gov/homepage/rap{_}tool.htm or through the CRE`s homepage at http://www.doe.gov/riskcenter/home.html.

  7. Damage assessment in systemic vasculitis.

    PubMed

    Silveira, Luis H

    2008-12-01

    Systemic vasculitides were initially reported as acute, progressive, severe, and life-threatening diseases. The introduction of glucocorticoids and cyclophosphamide for the treatment of vasculitis improved survival dramatically, but morbidity has remained high. Damage develops as a consequence of recurrent or persistent active vasculitis or its treatment. It is defined as the accumulation of nonhealing scars that are unlikely to respond to immunosuppressive therapy. Damage assessment is essential in systemic vasculitis because it may facilitate patient stratification in clinical trials and possibly in clinical practice. Moreover, it may avoid unnecessary use of immunosuppressive therapy. The Vasculitis Damage Index, developed and validated in 1997, has been very useful in solving many matters in systemic vasculitis and is currently the only validated damage-assessment tool available. However, the vasculitis community has recognized that there is a growing need to improve the evaluation of damage in vasculitis. The development of a Combined Damage Assessment index, which would permit a more appropriate and standardized approach to disease assessment applicable to systemic vasculitis, has been proposed.

  8. Edible moisture barriers: how to assess of their potential and limits in food products shelf-life extension?

    PubMed

    Bourlieu, C; Guillard, V; Vallès-Pamiès, B; Guilbert, S; Gontard, N

    2009-05-01

    Control of moisture transfer inside composite food products or between food and its environment remains today a major challenge in food preservation. A wide rage of film-forming compounds is now available and facilitates tailoring moisture barriers with optimized functional properties. Despite these huge potentials, a realistic assessment of the film or coating efficacy is still critical. Due to nonlinear water sorption isotherms, water-dependent diffusivities, and variations of physical state, modelling transport phenomena through edible barriers is complex. Water vapor permeability can hardly be considered as an inherent property of films and only gives a relative indication of the barrier efficacy. The formal or mechanistic models reported in literature that describe the influence of testing conditions on the barrier properties of edible films are reviewed and discussed. Most of these models have been validated on a narrow range of conditions. Conversely, few original predictive models based on Fick's Second Law have been developed to assess shelf-life extension of food products including barriers. These models, assuming complex and realistic hypothesis, have been validated in various model foods. The development of nondestructive methods of moisture content measurement should speed up model validation and allow a better comprehension of moisture transfer through edible films.

  9. Thermal and Environmental Barrier Coating Development for Advanced Propulsion Engine Systems

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Miller, Robert A.; Fox, Dennis S.

    2008-01-01

    Ceramic thermal and environmental barrier coatings (TEBCs) are used in gas turbine engines to protect engine hot-section components in the harsh combustion environments, and extend component lifetimes. Advanced TEBCs that have significantly lower thermal conductivity, better thermal stability and higher toughness than current coatings will be beneficial for future low emission and high performance propulsion engine systems. In this paper, ceramic coating design and testing considerations will be described for turbine engine high temperature and high-heat-flux applications. Thermal barrier coatings for metallic turbine airfoils and thermal/environmental barrier coatings for SiC/SiC ceramic matrix composite (CMC) components for future supersonic aircraft propulsion engines will be emphasized. Further coating capability and durability improvements for the engine hot-section component applications can be expected by utilizing advanced modeling and design tools.

  10. In vitro model systems for studying the impact of organic chemicals on the skin barrier lipids.

    PubMed

    Groen, Daniël; Berthaud, Fabienne; Bouwstra, Joke A; Chapuis, Christian; Gooris, Gert S; Boncheva, Mila

    2014-01-01

    This paper describes two synthetic lipid models designed to replace human stratum corneum (SC) in studies of the impact of volatile organic chemicals on the molecular organization of the skin barrier lipids. The models built upon previously developed self-assembled lipid membranes which have composition and 3D organization similar to those of the lipid matrix in SC. In one model the target chemicals were incorporated in the lipids before their self-assembly, and in the other one they were applied on top of a preformed lipid membrane. The chemicals could be incorporated within the model membranes in quantities close to those reached within human SC upon heavy surface loading. The dose-dependent effects of the chemicals on the lateral molecular organization in the models were qualitatively identical to those observed by infrared spectroscopy in human SC. The models facilitated the interpretation of X-ray diffraction profiles used to determine the nature of the interactions between the chemicals and the lipid lamellae and the position of the exogenous molecules within the unit cell of the lipid phases. These model systems are suitable for in vitro studies in the areas of skin biophysics, dermatology, transdermal drug delivery, and risk assessment.

  11. North Carolina Cooperative Extension Professionals' Climate Change Perceptions, Willingness, and Perceived Barriers to Programming: An Educational Needs Assessment

    ERIC Educational Resources Information Center

    Burnett, Rachel E.; Vuola, Aaron J.; Megalos, Mark A.; Adams, Damian C.; Monroe, Martha C.

    2014-01-01

    The educational needs assessment reported here measured North Carolina Cooperative Extension (NCCE) professionals' perceptions of global warming and identified barriers to climate change programming. Survey results from 400 NCCE professionals show 70% are cautious, concerned, or alarmed about global warming. Liberal and female Extension…

  12. North Carolina Cooperative Extension Professionals' Climate Change Perceptions, Willingness, and Perceived Barriers to Programming: An Educational Needs Assessment

    ERIC Educational Resources Information Center

    Burnett, Rachel E.; Vuola, Aaron J.; Megalos, Mark A.; Adams, Damian C.; Monroe, Martha C.

    2014-01-01

    The educational needs assessment reported here measured North Carolina Cooperative Extension (NCCE) professionals' perceptions of global warming and identified barriers to climate change programming. Survey results from 400 NCCE professionals show 70% are cautious, concerned, or alarmed about global warming. Liberal and female Extension…

  13. Review article: intestinal barrier dysfunction and central nervous system disorders--a controversial association.

    PubMed

    Julio-Pieper, M; Bravo, J A; Aliaga, E; Gotteland, M

    2014-11-01

    Central nervous system (CNS) development and physiopathology are greatly affected by environmental stimuli. The intestinal barrier restricts the entrance of toxins, pathogens, and antigens while modulating the expression of various neuroactive compounds. The existence of a rich gut-to-brain communication raises the possibility that intestinal barrier alterations may take part in the pathophysiology of CNS disorders. To review evidence associating intestinal barrier dysfunction with the development of CNS disorders. Literature search was conducted on PubMed using the following terms: intestinal barrier, intestinal permeability, central nervous system, mental disorders, schizophrenia, autism, stress, anxiety, depression, and neurodegeneration. Clinical and animal model studies of the association between intestinal barrier and schizophrenia, autism spectrum disorders, neurodegenerative diseases or depression were reviewed. The majority of reports concentrated on schizophrenia and autism spectrum disorders. About half of these described increased intestinal permeability/mucosal damage in patients compared with healthy controls, with up to 43% of children with autism spectrum disorders and up to 35% of schizophrenia patients displaying abnormally high urinary excretion of the sugars used as permeability markers. However, another substantial group of studies did not find such differences. In autism spectrum disorders, some reports show that the use of diets such as the gluten-free casein-free diet may contribute to the normalisation of lactulose/mannitol ratio, but to date there is no adequately controlled study showing improvement in behavioural symptoms following these dietary interventions. Evidence of altered intestinal permeability in individuals suffering from CNS disorders is limited and cannot be regarded as proven. Moreover the efficacy of targeting gut barrier in the management of neurological and behavioural aspects of CNS disorders has not yet been

  14. Skin barrier dysfunction and systemic sensitization to allergens through the skin.

    PubMed

    Strid, Jessica; Strobel, Stephan

    2005-10-01

    Most allergic, atopic and hypersensitive reactions are associated with Th2-biased immune responses and allergen-specific IgE antibodies. Pathological allergic disorders are on an alarming increase in the industrialized world. Understanding the mechanism of primary sensitization to allergens is important in elucidating the pathogenesis of these diseases and for possibly preventing their development. In this article, we review recent information supporting that epidermal allergen exposure may contribute to systemic allergic diseases and that atopy may be secondary to skin barrier dysfunction in some dermatoses. The skin is an active immunological organ, which functions as a primary defence and biosensor to the external environment. The critical permeability barrier function is mediated by the outmost layer of the epidermis, the stratum corneum. Perturbation of the stratum corneum initiates a chain of event, which activates homeostatic responses in the underlying epidermis. Repeated barrier-disruption, whether environmentally or genetically determined, may however stimulate signaling cascades that lead to inflammation and epidermal hyperplasia. Skin barrier dysfunction may also allow entry of allergens, which can lead to primary systemic sensitization. The altered epidermal microenvironment in barrier-disrupted skin appears to be particularly well suited for the induction of potent Th2-type responses with production of allergen-specific IgE. Epidermal exposure to food antigens can prevent the normal induction of oral tolerance and also lead to airway eosinophilia following inhalation. Exposure to allergens on barrier-disrupted skin may as such serve as a natural sensitization pathway for food allergy and respiratory allergic disease.

  15. Assessment of Residential GSHP System

    SciTech Connect

    Liu, Xiaobing

    2010-09-01

    This report first briefly reviews geothermal heat pump (GHP) technology and the current status of the GHP industry in the United States. Then it assesses the potential national benefits, in terms of energy savings, reduced summer peak electrical demand, consumer energy cost savings, and reduced CO{sub 2} emissions from retrofitting the space heating, space cooling, and water heating systems in existing U.S. single-family homes with state-of-the-art GHP systems. The investment for retrofitting typical U.S. single-family homes with state-of-the-art GHP systems is also analyzed using the metrics of net present value and levelized cost.

  16. Power Systems Development Facility. Environmental Assessment

    SciTech Connect

    Not Available

    1993-06-01

    The objective of the PSDF would be to provide a modular facility which would support the development of advanced, pilot-scale, coal-based power systems and hot gas clean-up components. These pilot-scale components would be designed to be large enough so that the results can be related and projected to commercial systems. The facility would use a modular approach to enhance the flexibility and capability for testing; consequently, overall capital and operating costs when compared with stand-alone facilities would be reduced by sharing resources common to different modules. The facility would identify and resolve technical barrier, as well as-provide a structure for long-term testing and performance assessment. It is also intended that the facility would evaluate the operational and performance characteristics of the advanced power systems with both bituminous and subbituminous coals. Five technology-based experimental modules are proposed for the PSDF: (1) an advanced gasifier module, (2) a fuel cell test module, (3) a PFBC module, (4) a combustion gas turbine module, and (5) a module comprised of five hot gas cleanup particulate control devices. The final module, the PCD, would capture coal-derived ash and particles from both the PFBC and advanced gasifier gas streams to provide for overall particulate emission control, as well as to protect the combustion turbine and the fuel cell.

  17. Drug Delivery Systems, CNS Protection, and the Blood Brain Barrier

    PubMed Central

    Upadhyay, Ravi Kant

    2014-01-01

    Present review highlights various drug delivery systems used for delivery of pharmaceutical agents mainly antibiotics, antineoplastic agents, neuropeptides, and other therapeutic substances through the endothelial capillaries (BBB) for CNS therapeutics. In addition, the use of ultrasound in delivery of therapeutic agents/biomolecules such as proline rich peptides, prodrugs, radiopharmaceuticals, proteins, immunoglobulins, and chimeric peptides to the target sites in deep tissue locations inside tumor sites of brain has been explained. In addition, therapeutic applications of various types of nanoparticles such as chitosan based nanomers, dendrimers, carbon nanotubes, niosomes, beta cyclodextrin carriers, cholesterol mediated cationic solid lipid nanoparticles, colloidal drug carriers, liposomes, and micelles have been discussed with their recent advancements. Emphasis has been given on the need of physiological and therapeutic optimization of existing drug delivery methods and their carriers to deliver therapeutic amount of drug into the brain for treatment of various neurological diseases and disorders. Further, strong recommendations are being made to develop nanosized drug carriers/vehicles and noninvasive therapeutic alternatives of conventional methods for better therapeutics of CNS related diseases. Hence, there is an urgent need to design nontoxic biocompatible drugs and develop noninvasive delivery methods to check posttreatment clinical fatalities in neuropatients which occur due to existing highly toxic invasive drugs and treatment methods. PMID:25136634

  18. Dynamic security assessment processing system

    NASA Astrophysics Data System (ADS)

    Tang, Lei

    The architecture of dynamic security assessment processing system (DSAPS) is proposed to address online dynamic security assessment (DSA) with focus of the dissertation on low-probability, high-consequence events. DSAPS upgrades current online DSA functions and adds new functions to fit into the modern power grid. Trajectory sensitivity analysis is introduced and its applications in power system are reviewed. An index is presented to assess transient voltage dips quantitatively using trajectory sensitivities. Then the framework of anticipatory computing system (ACS) for cascading defense is presented as an important function of DSAPS. ACS addresses various security problems and the uncertainties in cascading outages. Corrective control design is automated to mitigate the system stress in cascading progressions. The corrective controls introduced in the dissertation include corrective security constrained optimal power flow, a two-stage load control for severe under-frequency conditions, and transient stability constrained optimal power flow for cascading outages. With state-of-the-art computing facilities to perform high-speed extended-term time-domain simulation and optimization for large-scale systems, DSAPS/ACS efficiently addresses online DSA for low-probability, high-consequence events, which are not addressed by today's industrial practice. Human interference is reduced in the computationally burdensome analysis.

  19. Application of CFRP with High Hydrogen Gas Barrier Characteristics to Fuel Tanks of Space Transportation System

    NASA Astrophysics Data System (ADS)

    Yonemoto, Koichi; Yamamoto, Yuta; Okuyama, Keiichi; Ebina, Takeo

    In the future, carbon fiber reinforced plastics (CFRPs) with high hydrogen gas barrier performance will find wide applications in all industrial hydrogen tanks that aim at weight reduction; the use of such materials will be preferred to the use of conventional metallic materials such as stainless steel or aluminum. The hydrogen gas barrier performance of CFRP will become an important issue with the introduction of hydrogen-fuel aircraft. It will also play an important role in realizing fully reusable space transportation system that will have high specific tensile CFRP structures. Such materials are also required for the manufacture of high-pressure hydrogen gas vessels for use in the fuel cell systems of automobiles. This paper introduces a new composite concept that can be used to realize CFRPs with high hydrogen gas barrier performance for applications in the cryogenic tanks of fully reusable space transportation system by the incorporation of a nonmetallic crystal layer, which is actually a dense and highly oriented clay crystal laminate. The preliminary test results show that the hydrogen gas barrier characteristics of this material after cryogenic heat shocks and cyclic loads are still better than those of other polymer materials by approximately two orders of magnitude.

  20. Refining a questionnaire to assess breast cancer knowledge and barriers to screening in Kenya: Psychometric assessment of the BCAM.

    PubMed

    Wachira, J; Busakhala, A; Chite, F; Naanyu, V; Kisuya, J; Otieno, G; Keter, A; Mwangi, A; Inui, T

    2017-02-03

    Our study objective was to determine the validity and reliability of the breast module of a cancer awareness measure (BCAM) among adult women in western Kenya. The study was conducted between October and November 2012, following three breast cancer screening events. Purposive and systematic random sampling methods were used to identity 48 women for cognitive focus group discussions, and 1061 (594 who attended vs. 467 who did not attend screening events) for surveys, respectively. Face and psychometric validity of the BCAM survey was assessed using cognitive testing, factor analysis of survey data, and correlations. Internal reliability was assessed using Cronbach's alpha. Among survey participants, the overall median age was 34 (IQR: 26-44) years. Compared to those women who did not attend the screening events, women attendees were older (median: 35 vs. 32 years, p = 0.001) more often married (79% vs. 72%, p = 0.006), more educated (52% vs. 46% with more than an elementary level of education, p = 0.001), more unemployed (59% vs. 11%, p = 0.001), more likely to report doing breast self-examination (56% vs. 40%, p = 0.001) and more likely to report having felt a breast lump (16% vs. 7%, p = 0.001). For domain 1 on knowledge of breast cancer symptoms, one factor (three items) with Eigen value of 1.76 emerged for the group that did not attend screening, and 1.50 for the group that attended screening. For both groups two factors (factor 1 "internal influences" and factor 2 "external influences") emerged among domain 4 on barriers to screening, with varied item loadings and Eigen values. There were no statistically significant differences in the factor scores between attendees and non-attendees. There were significant associations between factor scores and other attributes of the surveyed population, including associations with occupation, transportation type, and training for and practice of breast self-examination. Cronbach's alpha showed an

  1. Leachate breakthrough mechanism and key pollutant indicator of municipal solid waste landfill barrier systems: Centrifuge and numerical modeling approach.

    PubMed

    Shu, Shi; Zhu, Wei; Wang, Shengwei; Ng, Charles Wang Wai; Chen, Yunmin; Chiu, Abraham Chung Fai

    2017-09-07

    Groundwater pollution by leachate leakage is one of the most common environmental hazards associated with municipal solid waste (MSW) landfill sites. However, landfill leachate contains a large variety of pollutants with widely different concentrations and biotoxicity. Thus, selecting leachate pollutant indicators and levels for identifying breakthrough of barrier systems are key factors in assessing their breakthrough times. This study investigated the transport behavior of leachate pollutants through landfill barrier systems using centrifuge tests and numerical modeling. The overall objective of this study is to investigate breakthrough mechanism to facilitate the establishment of a consistent pollutant threshold concentration for use as a groundwater pollution alert. The specific objective of the study is to identify which pollutant and breakthrough threshold concentration should be used as an indicator in the transport of multiple pollutants through a landfill barrier system. The threshold concentration from the Chinese groundwater quality standards was used in the analysis of the properties of leachates from many landfill sites in China. The time for the chemical oxygen demand (COD) to reach the breakthrough threshold concentration at the bottom of a 2m compacted clay liner was 1.51years according to centrifuge tests, and 1.81years according to numerical modeling. The COD breakthrough times for single and double composite liners were within the range of 16 and 36.58years. Of all the pollutants, COD was found to consistently reach the breakthrough threshold first. Therefore, COD can be selected as the key indicator for pollution alerts and used to assess the environmental risk posed by MSW landfill sites. Copyright © 2017. Published by Elsevier B.V.

  2. System facilitators and barriers to discussing older driver safety in primary care settings

    PubMed Central

    Betz, Marian E.; Jones, Jacqueline; Carr, David B.

    2015-01-01

    Background Primary care physicians play a leading role in counseling older drivers, but discussions often do not occur until safety concerns arise. Prior work suggests that routine questioning about driving might facilitate these difficult conversations. Objective To explore system-level factors affecting driving discussions in primary care settings, in order to inform the design and implementation of a program supporting routine conversations. Methods This qualitative descriptive study used iterative interviews with providers (physicians, nurses, medical assistants, social workers, and administrative staff) working at two clinics (one geriatric, one general internal medicine) at a tertiary-care teaching hospital. General inductive techniques in transcript analysis were used to identify stakeholder-perceived system-level barriers and facilitators to routine conversations with older drivers. Results From fifteen interviews, four themes emerged: (1) complexity of defined provider roles within primary care setting (which can both support team work and hamper efficiency); (2) inadequate resources to support providers (including clinical prompts, local guides, and access to social workers and driving specialists); (3) gaps in education of providers and patients about discussing driving; and (4) suggested models to enhance provider conversations with older drivers (including following successful examples and using defined pathways integrated into the electronic medical record). A fifth theme was that participants characterized their experiences in terms of current and ideal states. Conclusions Physicians have been tasked with assessing older driver safety and guiding older patients through the process of “driving retirement.” Attention to system-level factors such as provider roles, resources, and training can support them in this process. PMID:25617342

  3. Emittance and absorptance of NASA ceramic thermal barrier coating system. [for turbine cooling

    NASA Technical Reports Server (NTRS)

    Liebert, C. H.

    1978-01-01

    Spectral emittance measurements were made on a two-layer ceramic thermal barrier coating system consisting of a metal substrate, a NiCrAly bond coating and a yttria-stabilized zirconia ceramic coating. Spectral emittance data were obtained for the coating system at temperatures of 300 to 1590 K, ceramic thickness of zero to 0.076 centimeter, and wavelengths of 0.4 to 14.6 micrometers. The data were transformed into total hemispherical emittance values and correlated with respect to ceramic coating thickness and temperature using multiple regression curve fitting techniques. The results show that the ceramic thermal barrier coating system is highly reflective and significantly reduces radiation heat loads on cooled gas turbine engine components. Calculation of the radiant heat transfer within the nonisothermal, translucent ceramic coating material shows that the gas-side ceramic coating surface temperature can be used in heat transfer analysis of radiation heat loads on the coating system.

  4. Improving understanding of near-term barrier island evolution through multi-decadal assessment of morphologic change

    USGS Publications Warehouse

    Lentz, Erika E.; Hapke, Cheryl J.; Stockdon, Hilary F.; Hehre, Rachel E.

    2013-01-01

    Observed morphodynamic changes over multiple decades were coupled with storm-driven run-up characteristics at Fire Island, New York, to explore the influence of wave processes relative to the impacts of other coastal change drivers on the near-term evolution of the barrier island. Historical topography was generated from digital stereo-photogrammetry and compared with more recent lidar surveys to quantify near-term (decadal) morphodynamic changes to the beach and primary dune system between the years 1969, 1999, and 2009. Notably increased profile volumes were observed along the entirety of the island in 1999, and likely provide the eolian source for the steady dune crest progradation observed over the relatively quiescent decade that followed. Persistent patterns of erosion and accretion over 10-, 30-, and 40-year intervals are attributable to variations in island morphology, human activity, and variations in offshore bathymetry and island orientation that influence the wave energy reaching the coast. Areas of documented long-term historical inlet formation and extensive bayside marsh development show substantial landward translation of the dune–beach profile over the near-term period of this study. Correlations among areas predicted to overwash, observed elevation changes of the dune crestline, and observed instances of overwash in undeveloped segments of the barrier island verify that overwash locations can be accurately predicted in undeveloped segments of coast. In fact, an assessment of 2012 aerial imagery collected after Hurricane Sandy confirms that overwash occurred at the majority of near-term locations persistently predicted to overwash. In addition to the storm wave climate, factors related to variations within the geologic framework which in turn influence island orientation, offshore slope, and sediment supply impact island behavior on near-term timescales.

  5. Assessment & Commitment Tracking System (ACTS)

    SciTech Connect

    Bryant, Robert A.; Childs, Teresa A.; Miller, Michael A.; Sellars, Kevin J.

    2004-12-20

    The ACTS computer code provides a centralized tool for planning and scheduling assessments, tracking and managing actions associated with assessments or that result from an event or condition, and "mining" data for reporting and analyzing information for improving performance. The ACTS application is designed to work with the MS SQL database management system. All database interfaces are written in SQL. The following software is used to develop and support the ACTS application: Cold Fusion HTML JavaScript Quest TOAD Microsoft Visual Source Safe (VSS) HTML Mailer for sending email Microsoft SQL Microsoft Internet Information Server

  6. 77 FR 14032 - John H. Chafee Coastal Barrier Resources System; Lee County, FL, and Newport County, RI...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-08

    ... Fish and Wildlife Service John H. Chafee Coastal Barrier Resources System; Lee County, FL, and Newport... Service (Service), announce the availability of two John H. Chafee Coastal Barrier Resources System (CBRS... located in Newport County, Rhode Island. DATES: To ensure consideration, we must receive your...

  7. The Gulf Coast Vulnerability Assessment: Mangrove, Tidal Emergent Marsh, Barrier Islands, and Oyster Reef

    USGS Publications Warehouse

    Watson, Amanda; Reece, Joshua S.; Tirpak, Blair; Edwards, Cynthia Kallio; Geselbracht, Laura; Woodrey, Mark; LaPeyre, Megan K.; Dalyander, P. Soupy

    2015-01-01

    Climate, sea level rise, and urbanization are undergoing unprecedented levels of combined change and are expected to have large effects on natural resources—particularly along the Gulf of Mexico coastline (Gulf Coast). Management decisions to address these effects (i.e., adaptation) require an understanding of the relative vulnerability of various resources to these stressors. To meet this need, the four Landscape Conservation Cooperatives along the Gulf partnered with the Gulf of Mexico Alliance to conduct this Gulf Coast Vulnerability Assessment (GCVA). Vulnerability in this context incorporates the aspects of exposure and sensitivity to threats, coupled with the adaptive capacity to mitigate those threats. Potential impact and adaptive capacity reflect natural history features of target species and ecosystems. The GCVA used an expert opinion approach to qualitatively assess the vulnerability of four ecosystems: mangrove, oyster reef, tidal emergent marsh, and barrier islands, and a suite of wildlife species that depend on them. More than 50 individuals participated in the completion of the GCVA, facilitated via Ecosystem and Species Expert Teams. Of the species assessed, Kemp’s ridley sea turtle was identified as the most vulnerable species across the Gulf Coast. Experts identified the main threats as loss of nesting habitat to sea level rise, erosion, and urbanization. Kemp’s ridley also had an overall low adaptive capacity score due to their low genetic diversity, and higher nest site fidelity as compared to other assessed species. Tidal emergent marsh was the most vulnerable ecosystem, due in part to sea level rise and erosion. In general, avian species were more vulnerable than fish because of nesting habitat loss to sea level rise, erosion, and potential increases in storm surge. Assessors commonly indicated a lack of information regarding impacts due to projected changes in the disturbance regime, biotic interactions, and synergistic effects in both

  8. Gulf Coast vulnerability assessment: Mangrove, tidal emergent marsh, barrier islands and oyster reef

    USGS Publications Warehouse

    Watson, Amanda; Reece, Joshua; Tirpak, Blair; Edwards, Cynthia Kallio; Geselbracht, Laura; Woodrey, Mark; LaPeyre, Megan K.; Dalyander, Patricia (Soupy)

    2017-01-01

    Climate, sea level rise, and urbanization are undergoing unprecedented levels of combined change and are expected to have large effects on natural resources—particularly along the Gulf of Mexico coastline (Gulf Coast). Management decisions to address these effects (i.e., adaptation) require an understanding of the relative vulnerability of various resources to these stressors. To meet this need, the four Landscape Conservation Cooperatives along the Gulf partnered with the Gulf of Mexico Alliance to conduct this Gulf Coast Vulnerability Assessment (GCVA). Vulnerability in this context incorporates exposure and sensitivity to threats (potential impact), coupled with the adaptive capacity to mitigate those threats. Potential impact and adaptive capacity reflect natural history features of target species and ecosystems. The GCVA used an expert opinion approach to qualitatively assess the vulnerability of four ecosystems: mangrove, oyster reef, tidal emergent marsh, and barrier islands, and a suite of wildlife species that depend on them. More than 50 individuals participated in the completion of the GCVA, facilitated via Ecosystem and Species Expert Teams. Of the species assessed, Kemp’s ridley sea turtle was identified as the most vulnerable species across the Gulf Coast. Experts identified the main threats as loss of nesting habitat to sea level rise, erosion, and urbanization. Kemp’s ridley also had an overall low adaptive capacity score due to their low genetic diversity, and higher nest site fidelity as compared to other assessed species. Tidal emergent marsh was the most vulnerable ecosystem, due in part to sea level rise and erosion. In general, avian species were more vulnerable than fish because of nesting habitat loss to sea level rise, erosion, and potential increases in storm surge. Assessors commonly indicated a lack of information regarding impacts due to projected changes in the disturbance regime, biotic interactions, and synergistic effects in

  9. A behavior-based framework for assessing barrier effects to wildlife from vehicle traffic volume

    Treesearch

    Sandra L. Jacobson; Leslie L. Bliss-Ketchum; Catherine E. de Rivera; Winston P. Smith; D. P. C. Peters

    2016-01-01

    Roads, while central to the function of human society, create barriers to animal movement through collisions and habitat fragmentation. Barriers to animal movement affect the evolution and trajectory of populations. Investigators have attempted to use traffic volume, the number of vehicles passing a point on a road segment, to predict effects to wildlife populations...

  10. The Development and Evaluation of a Measure Assessing School Nurses' Perceived Barriers to Addressing Pediatric Obesity

    ERIC Educational Resources Information Center

    Wu, Yelena P.; Steele, Ric G.

    2011-01-01

    School nurses represent an important resource for addressing pediatric obesity and weight-related health. However, school nurses perceive numerous barriers that prevent them from addressing the weight-related health of students. The current study developed and tested a new, comprehensive measure of nurses' perceptions of 10 types of barriers to…

  11. Patterns of Physical Activity among American Indian Children: An Assessment of Barriers and Support.

    ERIC Educational Resources Information Center

    Thompson, Janice L.; Davis, Sally M.; Gittelsohn, Joel; Going, Scott; Becenti, Alberta; Metcalfe, Lauve; Stone, Elaine; Harnack, Lisa; Ring, Kim

    2001-01-01

    Evaluated barriers to participation in physical activity by American Indian elementary school students. Data from interviews, observations, and surveys indicated that barriers at school included lack of facilities, equipment, and trained staff people for physical education. Weather conditions, safety concerns, and homework/chores were also…

  12. Special Operations Forces Language and Culture Needs Assessment: Barriers to Language Acquisition and Maintenance

    DTIC Science & Technology

    2010-06-01

    2010 APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED SPONSORED BY: SOFLO, USSOCOM RESEARCH CONDUCTED BY: SWA CONSULTING INC. Special...Forces (SF) Command]. Two foundational reports document the methodology and participants associated with this project. Relationship of Barriers...removed. Research Questions This section addresses the following questions: • What are the biggest barriers to language acquisition and

  13. Assessment of Barriers for Midwives to Achieve Professional Management Positions from Midwives' Point of View

    PubMed Central

    Pourkazemi, Razieh; Beigi, Marjan; Kohan, Shahnaz

    2017-01-01

    Background: Despite the effects of midwives on the health of family and community through promotion of maternal and child health indicators, they are not in the position of professional decision making. Therefore, this study was aimed to determine the barriers to achieve professional management positions by midwives. Materials and Methods: This study was a descriptive and cross-sectional study. The members of board commission of midwifery and reproductive health, the academic members of midwifery department and midwives working at the adjutancy of health and treatment were selected from eight Iranian universities of medical sciences. Data was collected through demographic characteristics questionnaire, a researcher-made questionnaire about administrative barriers, and management skills. Validity and reliability of this tool was confirmed through content validity and Cronbach's alpha coefficient, and the results were analyzed using inferential statistics (analysis of variance and Kruskal–Wallis test). Results: The results of this study showed that the barriers for midwives to achieve professional management positions in order of preference were organizational barriers (71.4%), cultural barriers (42.4%), and individual barriers (30.8%). Conclusions: Based on the findings of this research, organizational barriers are the most important obstacle to achieve professional management positions. Therefore, the role of the authorities is emphasized to eliminate organizational barriers and provide more resources to reduce this problem. PMID:28706539

  14. The Development and Evaluation of a Measure Assessing School Nurses' Perceived Barriers to Addressing Pediatric Obesity

    ERIC Educational Resources Information Center

    Wu, Yelena P.; Steele, Ric G.

    2011-01-01

    School nurses represent an important resource for addressing pediatric obesity and weight-related health. However, school nurses perceive numerous barriers that prevent them from addressing the weight-related health of students. The current study developed and tested a new, comprehensive measure of nurses' perceptions of 10 types of barriers to…

  15. Astrocytic TYMP and VEGFA drive blood-brain barrier opening in inflammatory central nervous system lesions.

    PubMed

    Chapouly, Candice; Tadesse Argaw, Azeb; Horng, Sam; Castro, Kamilah; Zhang, Jingya; Asp, Linnea; Loo, Hannah; Laitman, Benjamin M; Mariani, John N; Straus Farber, Rebecca; Zaslavsky, Elena; Nudelman, German; Raine, Cedric S; John, Gareth R

    2015-06-01

    In inflammatory central nervous system conditions such as multiple sclerosis, breakdown of the blood-brain barrier is a key event in lesion pathogenesis, predisposing to oedema, excitotoxicity, and ingress of plasma proteins and inflammatory cells. Recently, we showed that reactive astrocytes drive blood-brain barrier opening, via production of vascular endothelial growth factor A (VEGFA). Here, we now identify thymidine phosphorylase (TYMP; previously known as endothelial cell growth factor 1, ECGF1) as a second key astrocyte-derived permeability factor, which interacts with VEGFA to induce blood-brain barrier disruption. The two are co-induced NFκB1-dependently in human astrocytes by the cytokine interleukin 1 beta (IL1B), and inactivation of Vegfa in vivo potentiates TYMP induction. In human central nervous system microvascular endothelial cells, VEGFA and the TYMP product 2-deoxy-d-ribose cooperatively repress tight junction proteins, driving permeability. Notably, this response represents part of a wider pattern of endothelial plasticity: 2-deoxy-d-ribose and VEGFA produce transcriptional programs encompassing angiogenic and permeability genes, and together regulate a third unique cohort. Functionally, each promotes proliferation and viability, and they cooperatively drive motility and angiogenesis. Importantly, introduction of either into mouse cortex promotes blood-brain barrier breakdown, and together they induce severe barrier disruption. In the multiple sclerosis model experimental autoimmune encephalitis, TYMP and VEGFA co-localize to reactive astrocytes, and correlate with blood-brain barrier permeability. Critically, blockade of either reduces neurologic deficit, blood-brain barrier disruption and pathology, and inhibiting both in combination enhances tissue preservation. Suggesting importance in human disease, TYMP and VEGFA both localize to reactive astrocytes in multiple sclerosis lesion samples. Collectively, these data identify TYMP as an

  16. Assessment of a Hydroxyapatite Permeable Reactive Barrier to Remediate Uranium at the Old Rifle Site Colorado.

    SciTech Connect

    Moore, Robert C.; Szecsody, James; Rigali, Mark J.; Vermuel, Vince; Leullen, Jon

    2016-02-01

    We have performed an initial evaluation and testing program to assess the effectiveness of a hydroxyapatite (Ca10(PO4)6(OH)2) permeable reactive barrier and source area treatment to decrease uranium mobility at the Department of Energy (DOE) former Old Rifle uranium mill processing site in Rifle, western Colorado. Uranium ore was processed at the site from the 1940s to the 1970s. The mill facilities at the site as well as the uranium mill tailings previously stored there have all been removed. Groundwater in the alluvial aquifer beneath the site still contains elevated concentrations of uranium, and is currently used for field tests to study uranium behavior in groundwater and investigate potential uranium remediation technologies. The technology investigated in this work is based on in situ formation of apatite in sediment to create a subsurface apatite PRB and also for source area treatment. The process is based on injecting a solution containing calcium citrate and sodium into the subsurface for constructing the PRB within the uranium plume. As the indigenous sediment micro-organisms biodegrade the injected citrate, the calcium is released and reacts with the phosphate to form hydroxyapatite (precipitate). This paper reports on proof-of-principle column tests with Old Rifle sediment and synthetic groundwater.

  17. Using the Complete Nano Engineering Geological Spectrum to Assess the Performance of Clay Barriers

    NASA Astrophysics Data System (ADS)

    Schmitz, Robrecht M.; Schroeder, Christian; Thorez, Jacques; Charlier, Robert

    Clays are geomaterials used in various (over 100) applications in our society. The more common geotechnical applications are clay barriers to contain waste, slurry walls etc. But even if clays are not used as construction material, the engineering geologist encounters them frequently during construction of e.g. foundations and tunnels. As clays are end products of the weathering of silicate geomaterials they are stable as such, but within this group of clay minerals, geotechnical properties vary enormously. Some of these variations are due to chemo-plasticity e.g. reflected in the effect of the composition of the pore fluid on the mechanical properties of clay. One approach to deal with these chemo plastic effects is to separate them according to the scale or level on which they are acting. In clays one can discern the level of the clay silicate sheets (TOT or TO), the clay interlayer level and the clay particles level. This contribution aims to show how an analysis of the processes on these three levels can help to assess the geotechnical properties of clays in contact with various fluids.

  18. Objective structured clinical examination for pharmacy students in Qatar: cultural and contextual barriers to assessment.

    PubMed

    Wilby, K J; Black, E K; Austin, Z; Mukhalalati, B; Aboulsoud, S; Khalifa, S I

    2016-07-10

    This study aimed to evaluate the feasibility and psychometric defensibility of implementing a comprehensive objective structured clinical examination (OSCE) on the complete pharmacy programme for pharmacy students in a Middle Eastern context, and to identify facilitators and barriers to implementation within new settings. Eight cases were developed, validated, and had standards set according to a blueprint, and were assessed with graduating pharmacy students. Assessor reliability was evaluated using inter-class coefficients (ICCs). Concurrent validity was evaluated by comparing OSCE results to professional skills course grades. Field notes were maintained to generate recommendations for implementation in other contexts. The examination pass mark was 424 points out of 700 (60.6%). All 23 participants passed. Mean performance was 74.6%. Low to moderate inter-rater reliability was obtained for analytical and global components (average ICC 0.77 and 0.48, respectively). In conclusion, OSCE was feasible in Qatar but context-related validity and reliability concerns must be addressed prior to future iterations in Qatar and elsewhere.

  19. Thermal Cycling Assessment of Steel-Based Thermal Barrier Coatings for Al Protection

    NASA Astrophysics Data System (ADS)

    Poirier, Dominique; Lamarre, Jean-Michel; Legoux, Jean-Gabriel

    2015-01-01

    There is a strong interest from the transportation industry to achieve vehicle weight reduction through the replacement of steel components by aluminum parts. For some applications, aluminum requires protective coatings due to its limited wear and lower temperature resistance compared to steel. The objective of this study was to assess the potential of amorphous-type plasma-sprayed steel coatings and conventional arc-sprayed steel coatings as thermal barrier coatings, mainly through the evaluation of their spalling resistance under thermal cycling. The microstructures of the different coatings were first compared via SEM. The amorphicity of the coatings produced via plasma spraying of specialized alloyed steel and the crystalline phases of the conventional arc-sprayed steel coatings were confirmed through x-ray diffraction. The thermal diffusivity of all coatings produced was measured to be about a third of that of bulk stainless steel. Conventional arc-sprayed steel coatings typically offered better spalling resistance under thermal cycling than steel-based amorphous coatings due probably to their higher initial bond strength. However, the presence of vertical cracks in the steel-based amorphous coatings was found to have a beneficial effect on their thermal cycling resistance. The amorphous plasma-sprayed steel coatings presented indications of recrystallization after their exposure to high temperature.

  20. Environmental impact assessment in urban transport planning: Exploring process-related barriers in Spanish practice

    SciTech Connect

    Soria-Lara, Julio A. Bertolini, Luca Brömmelstroet, Marco te

    2015-01-15

    The effectiveness of EIA for evaluating transport planning projects is increasingly being questioned by practitioners, institutions and scholars. The academic literature has traditionally focused more on solving content-related problems with EIA (i.e. the measurement of environmental effects) than on process-related issues (i.e. the role of EIA in the planning process and the interaction between key actors). Focusing only on technical improvements is not sufficient for rectifying the effectiveness problems of EIA. In order to address this knowledge gap, the paper explores how EIA is experienced in the Spanish planning context and offers in-depth insight into EIA process-related issues in the field of urban transport planning. From the multitude of involved actors, the research focuses on exploring the perceptions of the two main professional groups: EIA developers and transport planners. Through a web-based survey we assess the importance of process-related barriers to the effective use of EIA in urban transport planning. The analyses revealed process issues based fundamentally on unstructured stakeholders involvement and an inefficient public participation - Highlights: • Qualitative research on perceptions of EIA participants on EIA processes. • Web-based survey with different participants (EIA-developers; transport planners). • It was seen an inefficient participation of stakeholders during the EIA processes.

  1. A methodological framework to assess the environmental and economic effects of injection barriers against seawater intrusion.

    PubMed

    Siarkos, Ilias; Latinopoulos, Dionysis; Mallios, Zisis; Latinopoulos, Pericles

    2017-05-15

    Seawater intrusion is responsible for the progressive deterioration of groundwater quality in numerous coastal aquifers worldwide. As a consequence, seawater intrusion may constitute a serious threat to local groundwater resources, as well as to the regional economy of coastal areas. To alleviate these negative effects, a number of well-designed protective measures could be implemented. The implementation of these measures is usually associated with significant benefits for the environment and the local economy. In this perspective, the present study investigates the particular case of constructing injection barriers for controlling seawater intrusion by developing a methodological framework that combines numerical modeling with spatial and cost-benefit analyses. To this task, we introduce a novel approach, which considers the socio-economic aspects of seawater intrusion in the modeling procedure, and at the same time focuses on the spatial and temporal relationships between water salinity and farmers' income. To test the proposed methodology two alternative artificial recharge scenarios - with different volumes of water used for injection - are assessed. According to the results of this analysis, both scenarios are likely to have a positive impact on groundwater quality, as well as, a net economic benefit to local society.

  2. Free energy barriers for homogeneous crystal nucleation in a eutectic system of binary hard spheres.

    PubMed

    Ganagalla, Srinivasa Rao; Punnathanam, Sudeep N

    2013-05-07

    In this study, the free energy barriers for homogeneous crystal nucleation in a system that exhibits a eutectic point are computed using Monte Carlo simulations. The system studied is a binary hard sphere mixture with a diameter ratio of 0.85 between the smaller and larger hard spheres. The simulations of crystal nucleation are performed for the entire range of fluid compositions. The free energy barrier is found to be the highest near the eutectic point and is nearly five times that for the pure fluid, which slows down the nucleation rate by a factor of 10(-31). These free energy barriers are some of highest ever computed using simulations. For most of the conditions studied, the composition of the critical nucleus corresponds to either one of the two thermodynamically stable solid phases. However, near the eutectic point, the nucleation barrier is lowest for the formation of the metastable random hexagonal closed packed (rhcp) solid phase with composition lying in the two-phase region of the phase diagram. The fluid to solid phase transition is hypothesized to proceed via formation of a metastable rhcp phase followed by a phase separation into respective stable fcc solid phases.

  3. Barriers within the health care system to dealing with sexualized violence: a literature review.

    PubMed

    Rönnberg, A K; Hammarström, A

    2000-09-01

    The aim of this study was to review the literature about possible barriers to recognition and intervention regarding women exposed to sexualized violence, in their interactions with the health care system. The barriers, as reported by the health care staff, were: lack of education; the stereotype of a "typical battered woman"; too close identification with the victim/abuser; time constraints; fear of offending the victim/abuser; and feelings of hopelessness and non-responsibility. The barriers, as reported by the victims, were: negative experiences of and structural limitations within the health care system; fear of retaliation from the abusive partner; and psychological effects of the normalization process. We conclude that the barriers within the health care sector have to be dealt with on three different levels: the structural level in order to diminish male power in society; the organizational level in order to initiate screening and to allow the staff time for dealing with the victims; and on the individual level, health care staff need to acquire the knowledge and skills to enable them to address sexualized violence.

  4. Assessing Transplant Attitudes: Understanding Minority Men's Perspectives on the Multifarious Barriers to Organ Donation.

    PubMed

    Hinck, Bryan D; Naelitz, Bryan D; Jackson, Brielle; Howard, Mariah; Nowacki, Amy; Modlin, Charles S

    2016-06-28

    African Americans comprise 11 % of living organ donors, yet constitute 34 % of the kidney transplant waiting list. There are many barriers to organ donation among minorities that include decreased awareness of transplantation, cultural mistrust of the medical community, financial concerns, and fear of the transplant operation. This study investigates the societal misconceptions and demographic health factors that correlate with minority participation in organ and tissue donation. A 57 question Health and Wellness survey was designed to assess participants' demographic information, medical history, professional background, and opinions regarding organ transplantation. Participants were also asked to complete Quality Metric's Short Form-8 (SF-8) survey to assess physical health, mental health, and quality-of-life. Three hundred twenty-six surveys were administered to minority men. The majority of men were identified as African American, and 55 % were below the age of 40. Though 44 % of participants were willing to donate, only 27 % were registered as organ and tissue donors. Minorities who held misconceptions about organ donation-including the belief that they were too old or unhealthy to donate, for example-had lower general, physical, and mental health scores than those who did not (p = <0.0001). Minorities aware of the shortage for organs or who know a registered donor, an organ recipient, a dialysis patient, or someone on the waiting list were more willing to donate organs. Improving the general, physical, and mental health of minorities, coupled with an active educational outreach program, could result in a greater percentage of minorities registering and willing to be organ and tissue donors.

  5. Assessment of blood–brain barrier disruption using dynamic contrast-enhanced MRI. A systematic review

    PubMed Central

    Heye, Anna K.; Culling, Ross D.; Valdés Hernández, Maria del C.; Thrippleton, Michael J.; Wardlaw, Joanna M.

    2014-01-01

    There is increasing recognition of the importance of blood–brain barrier (BBB) disruption in aging, dementia, stroke and multiple sclerosis in addition to more commonly-studied pathologies such as tumors. Dynamic contrast-enhanced MRI (DCE-MRI) is a method for studying BBB disruption in vivo. We review pathologies studied, scanning protocols and data analysis procedures to determine the range of available methods and their suitability to different pathologies. We systematically review the existing literature up to February 2014, seeking studies that assessed BBB integrity using T1-weighted DCE-MRI techniques in animals and humans in normal or abnormal brain tissues. The literature search provided 70 studies that were eligible for inclusion, involving 417 animals and 1564 human subjects in total. The pathologies most studied are intracranial neoplasms and acute ischemic strokes. There are large variations in the type of DCE-MRI sequence, the imaging protocols and the contrast agents used. Moreover, studies use a variety of different methods for data analysis, mainly based on model-free measurements and on the Patlak and Tofts models. Consequently, estimated KTrans values varied widely. In conclusion, DCE-MRI is shown to provide valuable information in a large variety of applications, ranging from common applications, such as grading of primary brain tumors, to more recent applications, such as assessment of subtle BBB dysfunction in Alzheimer's disease. Further research is required in order to establish consensus-based recommendations for data acquisition and analysis and, hence, improve inter-study comparability and promote wider use of DCE-MRI. PMID:25379439

  6. In vivo assessment of the permeability of the blood-brain barrier and blood-retinal barrier to fluorescent indoline derivatives in zebrafish

    PubMed Central

    2012-01-01

    Background Successful delivery of compounds to the brain and retina is a challenge in the development of therapeutic drugs and imaging agents. This challenge arises because internalization of compounds into the brain and retina is restricted by the blood–brain barrier (BBB) and blood-retinal barrier (BRB), respectively. Simple and reliable in vivo assays are necessary to identify compounds that can easily cross the BBB and BRB. Methods We developed six fluorescent indoline derivatives (IDs) and examined their ability to cross the BBB and BRB in zebrafish by in vivo fluorescence imaging. These fluorescent IDs were administered to live zebrafish by immersing the zebrafish larvae at 7-8 days post fertilization in medium containing the ID, or by intracardiac injection. We also examined the effect of multidrug resistance proteins (MRPs) on the permeability of the BBB and BRB to the ID using MK571, a selective inhibitor of MRPs. Results The permeability of these barriers to fluorescent IDs administered by simple immersion was comparable to when administered by intracardiac injection. Thus, this finding supports the validity of drug administration by simple immersion for the assessment of BBB and BRB permeability to fluorescent IDs. Using this zebrafish model, we demonstrated that the length of the methylene chain in these fluorescent IDs significantly affected their ability to cross the BBB and BRB via MRPs. Conclusions We demonstrated that in vivo assessment of the permeability of the BBB and BRB to fluorescent IDs could be simply and reliably performed using zebrafish. The structure of fluorescent IDs can be flexibly modified and, thus, the permeability of the BBB and BRB to a large number of IDs can be assessed using this zebrafish-based assay. The large amount of data acquired might be useful for in silico analysis to elucidate the precise mechanisms underlying the interactions between chemical structure and the efflux transporters at the BBB and BRB. In turn

  7. Assessing Respiratory System Mechanical Function.

    PubMed

    Restrepo, Ruben D; Serrato, Diana M; Adasme, Rodrigo

    2016-12-01

    The main goals of assessing respiratory system mechanical function are to evaluate the lung function through a variety of methods and to detect early signs of abnormalities that could affect the patient's outcomes. In ventilated patients, it has become increasingly important to recognize whether respiratory function has improved or deteriorated, whether the ventilator settings match the patient's demand, and whether the selection of ventilator parameters follows a lung-protective strategy. Ventilator graphics, esophageal pressure, intra-abdominal pressure, and electric impedance tomography are some of the best-known monitoring tools to obtain measurements and adequately evaluate the respiratory system mechanical function.

  8. Quantitative risk assessment system (QRAS)

    NASA Technical Reports Server (NTRS)

    Weinstock, Robert M (Inventor); Smidts, Carol S (Inventor); Mosleh, Ali (Inventor); Chang, Yung-Hsien (Inventor); Swaminathan, Sankaran (Inventor); Groen, Francisco J (Inventor); Tan, Zhibin (Inventor)

    2001-01-01

    A quantitative risk assessment system (QRAS) builds a risk model of a system for which risk of failure is being assessed, then analyzes the risk of the system corresponding to the risk model. The QRAS performs sensitivity analysis of the risk model by altering fundamental components and quantifications built into the risk model, then re-analyzes the risk of the system using the modifications. More particularly, the risk model is built by building a hierarchy, creating a mission timeline, quantifying failure modes, and building/editing event sequence diagrams. Multiplicities, dependencies, and redundancies of the system are included in the risk model. For analysis runs, a fixed baseline is first constructed and stored. This baseline contains the lowest level scenarios, preserved in event tree structure. The analysis runs, at any level of the hierarchy and below, access this baseline for risk quantitative computation as well as ranking of particular risks. A standalone Tool Box capability exists, allowing the user to store application programs within QRAS.

  9. Diffusive Transport of Sulphide through an Engineering Barrier System in a Deep Geological Repository

    NASA Astrophysics Data System (ADS)

    Briggs, S. A.; Sleep, B. E.; McKelvie, J. R. M.; Krol, M.

    2015-12-01

    Bentonite is a naturally occurring clay-rich sediment containing montmorillonite, a smectitic clay mineral that has a high cation exchange capacity and swells upon contact with water. Owing to these characteristics, highly compacted bentonite (HCB) is an often included component of engineered barrier systems (EBS) designed to protect used fuel containers (UFCs) in deep geological repositories (DGR) for high-level nuclear waste. The low water activity and high swelling pressure of HCB suppresses microbial activity and the related production of sulphide that could cause microbiologically influenced corrosion (MIC) of UFCs The Canadian Nuclear Waste Management Organization (NWMO) has chosen a UFC that consists of an inner steel core and outer copper coating which is resistant to corrosion. However, under anaerobic conditions, MIC can still contribute to UFC corrosion if sulphides are present in the groundwater. Therefore the EBS consisting of bentonite blocks and pellets has been designed to impede the movement of sulphides to the UFC. In order to examine the effectiveness of the EBS, a 3D numerical model was developed capable of simulating the diffusive transport of sulphide within the NWMO EBS. The model was developed using COMSOL Multiphysics, a finite element software package and is parametric which allows the impact of different repository layouts to be assessed. The developed model was of the entire NWMO placement room, as well as, a stand-alone UFC and included conservative assumptions such as a fully saturated system and a constant concentration boundary condition. The results showed that the highest sulphide flux occurred at the semi-spherical end caps of the UFC. Further studies examined the effect of sulphide hotspots and fractures, representing possible EBS failure mechanisms. The model results highlight that even with conservative assumptions the chosen EBS will effectively protect the UFC from microbiologically influenced corrosion.

  10. Demonstrating and assessing metered-dose inhaler-spacer technique: pediatric care providers' self-reported practices and perceived barriers.

    PubMed

    Reznik, Marina; Jaramillo, Yudilyn; Wylie-Rosett, Judith

    2014-03-01

    The National Asthma Education and Prevention Program recommends that providers demonstrate and assess metered-dose inhaler-spacer (MDI-S) technique at each medical visit. To examine practice behaviors and perceived barriers to demonstrating and assessing MDI-S technique, we surveyed pediatric providers (n = 114) at an inner-city academic medical center. While 82% of providers demonstrated MDI-S technique, only 5% of providers demonstrate the technique at every visit. Although 67% of providers assessed MDI-S technique, only 13% assess the technique at every visit. None of the providers used MDI-S checklist for assessment. Attendings were more likely than residents to demonstrate with illustrations (24% vs 6%, P = .01) and when patient's asthma was not well controlled (68% vs 47%, P = .05). Provider-identified barriers included limited access to MDI-S device, lack of time, and inadequate knowledge. Suggestions to address barriers include in-service training, device access, and nurse/health educators to alleviate the time constraints. Clinic modifications and education are needed.

  11. Corral Monitoring System assessment results

    SciTech Connect

    Filby, E.E.; Haskel, K.J.

    1998-03-01

    This report describes the results of a functional and operational assessment of the Corral Monitoring Systems (CMS), which was designed to detect and document accountable items entering or leaving a monitored site. Its development was motivated by the possibility that multiple sites in the nuclear weapons states of the former Soviet Union might be opened to such monitoring under the provisions of the Strategic Arms Reduction Treaty. The assessment was performed at three levels. One level evaluated how well the planned approach addressed the target application, and which involved tracking sensitive items moving into and around a site being monitored as part of an international treaty or other agreement. The second level examined the overall design and development approach, while the third focused on individual subsystems within the total package. Unfortunately, the system was delivered as disassembled parts and pieces, with very poor documentation. Thus, the assessment was based on fragmentary operating data coupled with an analysis of what documents were provided with the system. The system design seemed to be a reasonable match to the requirements of the target application; however, important questions about site manning and top level administrative control were left unanswered. Four weaknesses in the overall design and development approach were detected: (1) poor configuration control and management, (2) inadequate adherence to a well defined architectural standard, (3) no apparent provision for improving top level error tolerance, and (4) weaknesses in the object oriented programming approach. The individual subsystems were found to offer few features or capabilities that were new or unique, even at the conceptual level. The CMS might possibly have offered a unique combination of features, but this level of integration was never realized, and it had no unique capabilities that could be readily extracted for use in another system.

  12. Advanced thermal barrier system bond coatings for use on nickel-, cobalt- and iron-base alloy substrates

    NASA Technical Reports Server (NTRS)

    Stecura, S.

    1986-01-01

    New and improved Ni-, Co-, and Fe-base bond coatings have been identified for the ZrO2-Y2O3 thermal barrier coatings to be used on Ni-, Co-, and Fe-base alloy substrates. These bond coatings were evaluated in a cyclic furnace between 1120 and 1175 C. It was found that MCrAlYb (where M = Ni, Co, or Fe) bond coating thermal barrier systems have significantly longer lives than MCrAlY bond coating thermal barrier systems. The longest life was obtained with the FeCrAlYb thermal barrier system followed by NiCrAlYb and CoCrAlYb thermal barrier systems in that order.

  13. Advanced thermal barrier system bond coatings for use on nickel-, cobalt- and iron-base alloy substrates

    NASA Technical Reports Server (NTRS)

    Stecura, S.

    1986-01-01

    New and improved Ni-, Co-, and Fe-base bond coatings have been identified for the ZrO2-Y2O3 thermal barrier coatings to be used on Ni-, Co-, and Fe-base alloy substrates. These bond coatings were evaluated in a cyclic furnace between 1120 and 1175 C. It was found that MCrAlYb (where M = Ni, Co, or Fe) bond coating thermal barrier systems have significantly longer lives than MCrAlY bond coating thermal barrier systems. The longest life was obtained with the FeCrAlYb thermal barrier system followed by NiCrAlYb and CoCrAlYb thermal barrier systems in that order.

  14. Reducing Barriers To The Use of High-Efficiency Lighting Systems

    SciTech Connect

    Peter Morante

    2005-12-31

    With funding from the U.S. Department of Energy (DOE), the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute completed the four-year research project, Reducing Barriers to the Use of High-Efficiency Lighting Systems. The initial objectives were: (1) identifying barriers to widespread penetration of lighting controls in commercial/industrial (C/I) applications that employ fluorescent lamp technologies, and (2) making recommendations to overcome these barriers. The addition of a fourth year expanded the original project objectives to include an examination of the impact on fluorescent lamps from dimming utilizing different lamp electrode heating and dimming ratios. The scope of the project was narrowed to identify barriers to the penetration of lighting controls into commercial-industrial (C/I) applications that employ fluorescent lamp technologies, and to recommend means for overcoming these barriers. Working with lighting manufacturers, specifiers, and installers, the project identified technological and marketing barriers to the widespread use of lighting controls, specifically automatic-off controls, occupancy sensors, photosensors, dimming systems, communication protocols and load-shedding ballasts. The primary barriers identified include cost effectiveness of lighting controls to the building owner, lack of standard communication protocols to allow different part of the control system to communicate effectively, and installation and commissioning issues. Overcoming the identified barriers requires lighting control products on the market to achieve three main goals: (1) Achieve sufficient functionality to meet the key requirements of their main market. (2) Allow significant cost reduction compared to current market standard systems. Cost should consider: hardware capital cost including wiring, design time required by the specifier and the control system manufacturer, installation time required by the electrician, and commissioning time and

  15. OVERVIEW OF THE U.S. DEPARTMENT OF ENERGY AND NUCLEAR REGULATORY COMMISSION PERFORMANCE ASSESSMENT APPROACHES: CEMENTITIOUS BARRIERS PARTNERSHIP

    SciTech Connect

    Langton, C.; Burns, H.

    2009-05-29

    Engineered barriers including cementitious barriers are used at sites disposing or contaminated with low-level radioactive waste to enhance performance of the natural environment with respect to controlling the potential spread of contaminants. Drivers for using cementitious barriers include: high radionuclide inventory, radionuclide characteristics (e.g., long half-live, high mobility due to chemical form/speciation, waste matrix properties, shallow water table, and humid climate that provides water for leaching the waste). This document comprises the first in a series of reports being prepared for the Cementitious Barriers Partnership. The document is divided into two parts which provide a summary of: (1) existing experience in the assessment of performance of cementitious materials used for radioactive waste management and disposal and (2) sensitivity and uncertainty analysis approaches that have been applied for assessments. Each chapter is organized into five parts: Introduction, Regulatory Considerations, Specific Examples, Summary of Modeling Approaches and Conclusions and Needs. The objective of the report is to provide perspective on the state of the practice for conducting assessments for facilities involving cementitious barriers and to identify opportunities for improvements to the existing approaches. Examples are provided in two contexts: (1) performance assessments conducted for waste disposal facilities and (2) performance assessment-like analyses (e.g., risk assessments) conducted under other regulatory regimes. The introductory sections of each section provide a perspective on the purpose of performance assessments and different roles of cementitious materials for radioactive waste management. Significant experience with assessments of cementitious materials associated with radioactive waste disposal concepts exists in the US Department of Energy Complex and the commercial nuclear sector. Recently, the desire to close legacy facilities has created

  16. Gastric yield pressure and gastric yield volume to assess anti-reflux barrier in a porcine model.

    PubMed

    Duarte, Marcos E S; Freitag, Carmen P F; Fornari, Fernando; Kruel, Cleber R P; Sanches, Paulo R S; Thomé, Paulo R O; Callegari-Jacques, Sidia M; Möllerke, Roseli O; Vicente, Yvone A M V A; Goldani, Helena A S; Barros, Sérgio G S

    2013-04-01

    Anti-reflux barrier (ARB) resistance may be useful to test new treatments for gastroesophageal reflux (GER). The ARB has been estimated by increasing gastric yield pressure (GYP) and gastric yield volume (GYV) in animal models but has not been validated. This study aimed to develop an experimental model suitable for assessing the ARB resistance to increasing intragastric pressure and volume and its reproducibility in a seven-day interval. Ten two-month-old female Large-White swine were studied. Intragastric pressure and volume were recorded using a digital system connected to a Foley catheter inserted through gastrostomy into the stomach. GYP and GYV were defined as the gastric pressure and volume able to yield gastric contents into the esophagus detected by esophageal pH. A sudden pH drop below 3 sustained during 5 min was considered diagnostic for gastric yield. Animals were studied again after seven days. On days 0 and 7, there were no significant differences for GYP (mean ± SD = 7.66 ± 3.02 mmHg vs. 7.07 ± 3.54 mmHg, p = .686) and GYV (636.70 ± 216.74 ml vs. 608.30 ± 276.66 ml; p = .299), respectively. Concordance correlation coefficient (ρc) was significant for GYP (ρc = 0.634, 95% CI = 0.141-0.829, p = .006), but not for GYV (ρc = 0.291, 95% CI = -0.118 to 0.774, p = .196). This study demonstrated an experimental model, assessing the ARB resistance. GYP seems to be a more reliable parameter than GYV for assessment of ARB resistance.

  17. Performance Assessment of a Permeable Reactive Barrier for Ground Water Remediation Fifteen Years After Installation

    EPA Science Inventory

    The fifteen-year performance of a granular iron, permeable reactive barrier (PRB; Elizabeth City, North Carolina) is reviewed with respect to contaminanttreatment (hexavalent chromium and trichloroethylene) and hydraulic performance. Due to in-situ treatment of the chromium sourc...

  18. Performance Assessment of a Permeable Reactive Barrier for Ground Water Remediation Fifteen Years After Installation

    EPA Science Inventory

    The fifteen-year performance of a granular iron, permeable reactive barrier (PRB; Elizabeth City, North Carolina) is reviewed with respect to contaminanttreatment (hexavalent chromium and trichloroethylene) and hydraulic performance. Due to in-situ treatment of the chromium sourc...

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

    EPA Science Inventory

    Permeable reactive barriers (PRBs) are an emerging, alternative in-situ approach for remediating groundwater contamination that combine subsurface fluid flow management with a passive chemical treatment zone. The few pilot and commercial installations which have been implemented ...

  20. Communication barriers for deaf employees: Needs assessment and problem-solving strategies.

    PubMed

    Luft, Pamela

    2000-01-01

    Deaf people experience higher rates of unemployment and underemployment and earn lifetime wages that are between $356,000 and $609,000 less than their comparably educated normally hearing counterparts. This results in a substantial loss of earning power and career identity for members of this underutilized population of workers. This article examines how communication difficulties pose a major barrier to employment retention and advancement for deaf employees. These barriers exist (a) within the employee in terms of nonfluent use of English and reliance upon American Sign Language, (b) with the employment site, and (c) with agency service personnel. Primarily, these barriers reflect a lack of understanding of the cultural and communication needs of deaf people. Strategies to ameliorate these barriers include a model of long-term employment support using an ecological framework.

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

    EPA Science Inventory

    Permeable reactive barriers (PRBs) are an emerging, alternative in-situ approach for remediating groundwater contamination that combine subsurface fluid flow management with a passive chemical treatment zone. The few pilot and commercial installations which have been implemented ...

  2. Transfer reactions for the /sup 50/Ti + /sup 90/Zr system below the Coulomb barrier

    SciTech Connect

    Kim, H.J.; Gomez del Campo, J.; Hindi, M.M.; Shapira, D.; Stelson, P.H.

    1988-11-01

    The analysis of quasielastic cross section data for the /sup 90/Zr projectile plus /sup 50/Ti target system shows that the probability for /sup 50/Ti(/sup 90/Zr, /sup 49/Ti)/sup 91/Zr, 1n-transfer reaction near the barrier is much larger than estimates based on semiclassical theory. The probability for /sup 50/Ti(/sup 90/Zr,/sup 51/V)/sup 89/Y, 1p-transfer reaction, on the other hand, agrees with the same theory. The internuclear distance where the 1n-transfer probability first deviates from tunneling predictions coincides with the threshold of the fusion barrier distribution deduced from the experimental fusion cross sections of the /sup 50/Ti+/sup 90/Zr system, suggesting a common mechanism for the large enhancement of 1n-transfer and fusion cross sections.

  3. A Cognitive Framework for Understanding Barriers to the Productive Use of a Diabetes Home Telemedicine System

    PubMed Central

    Kaufman, David R.; Starren, Justin; Patel, Vimla L.; Morin, Philip C.; Hilliman, Charlyn; Pevzner, Jenia; Weinstock, Ruth S.; Goland, Robin; Shea, Steven

    2003-01-01

    Telemedicine has the potential to transcend geographic and socio-cultural barriers to the delivery of high quality health care to the medically underserved populations. However, there are significant cognitive and usability barriers. This paper presents a multifaceted cognitive evaluation of the IDEATel diabetes education and telemedicine program. The evaluation included a cognitive walkthrough analysis to characterize task complexity and identify potential problems as well as field usability testing in patients’ homes. The study revealed dimensions of the interface that impeded optimal access to system resources. In addition, we found significant obstacles corresponding to perceptual-motoric skills, mental models of the system, and health literacy. The objective of this work is to contribute to a design framework so that participants with a wide range of skills can better manage their chronic illnesses. PMID:14728194

  4. A cognitive framework for understanding barriers to the productive use of a diabetes home telemedicine system.

    PubMed

    Kaufman, David R; Starren, Justin; Patel, Vimla L; Morin, Philip C; Hilliman, Charlyn; Pevzner, Jenia; Weinstock, Ruth S; Goland, Robin; Shea, Steven

    2003-01-01

    Telemedicine has the potential to transcend geographic and socio-cultural barriers to the delivery of high quality health care to the medically underserved populations. However, there are significant cognitive and usability barriers. This paper presents a multifaceted cognitive evaluation of the IDEATel diabetes education and telemedicine program. The evaluation included a cognitive walkthrough analysis to characterize task complexity and identify potential problems as well as field usability testing in patients' homes. The study revealed dimensions of the interface that impeded optimal access to system resources. In addition, we found significant obstacles corresponding to perceptual-motoric skills, mental models of the system, and health literacy. The objective of this work is to contribute to a design framework so that participants with a wide range of skills can better manage their chronic illnesses.

  5. Bone marrow transplantation concurrently reconstitutes donor liver and immune system across host species barrier in mice.

    PubMed

    Qi, Ziping; Li, Lu; Wang, Xuefu; Gao, Xiang; Wang, Xin; Wei, Haiming; Zhang, Jian; Sun, Rui; Tian, Zhigang

    2014-01-01

    Liver immunopathologic mechanisms during hepatotropic infection, malignant transformation, and autoimmunity are still unclear. Establishing a chimeric mouse with a reconstituted liver and immune system derived from a single donor across species is critical to study regional donor immune responses in recipient liver. Using a strain of mice deficient in tyrosine catabolic enzyme fumarylacetoacetate hydrolase (fah-/-) and bone marrow transplantation (BMT), we reconstituted the donor's hepatocytes and immune cells across host species barrier. Syngeneic, allogeneic or even xenogeneic rat BMT rescued most recipient fah-/- mice against liver failure by donor BM-derived FAH+ hepatocytes. Importantly, immune system developed normally in chimeras, and the immune cells together with organ architecture were intact and functional. Thus, donor BM can across host species barrier and concurrently reconstitutes MHC-identical response between immune cells and hepatocytes, giving rise to a new simple and convenient small animal model to study donor's liver immune response in mice.

  6. Bone Marrow Transplantation Concurrently Reconstitutes Donor Liver and Immune System across Host Species Barrier in Mice

    PubMed Central

    Qi, Ziping; Li, Lu; Wang, Xuefu; Gao, Xiang; Wang, Xin; Wei, Haiming; Zhang, Jian; Sun, Rui; Tian, Zhigang

    2014-01-01

    Liver immunopathologic mechanisms during hepatotropic infection, malignant transformation, and autoimmunity are still unclear. Establishing a chimeric mouse with a reconstituted liver and immune system derived from a single donor across species is critical to study regional donor immune responses in recipient liver. Using a strain of mice deficient in tyrosine catabolic enzyme fumarylacetoacetate hydrolase (fah-/-) and bone marrow transplantation (BMT), we reconstituted the donor's hepatocytes and immune cells across host species barrier. Syngeneic, allogeneic or even xenogeneic rat BMT rescued most recipient fah-/- mice against liver failure by donor BM-derived FAH+ hepatocytes. Importantly, immune system developed normally in chimeras, and the immune cells together with organ architecture were intact and functional. Thus, donor BM can across host species barrier and concurrently reconstitutes MHC-identical response between immune cells and hepatocytes, giving rise to a new simple and convenient small animal model to study donor's liver immune response in mice. PMID:25191899

  7. Sub-Barrier Fusion Calculations for the {sup 9}Li+{sup 70}Zn System

    SciTech Connect

    Balantekin, A. B.; Kocak, G.

    2008-11-11

    Sub-barrier fusion cross sections for the {sup 9}Li+{sup 70}Zn system are analyzed within the framework of the coupled channels model. We find that inclusion of the inelastic and one-neutron transfer channels in the coupled-channels calculations fails to reproduce the data. We find that possible formation of a molecular bond accompanied by two-neutron transfer may account for the observed behavior.

  8. Run-up parameterization and beach vulnerability assessment on a barrier island: a downscaling approach

    NASA Astrophysics Data System (ADS)

    Medellín, G.; Brinkkemper, J. A.; Torres-Freyermuth, A.; Appendini, C. M.; Mendoza, E. T.; Salles, P.

    2016-01-01

    We present a downscaling approach for the study of wave-induced extreme water levels at a location on a barrier island in Yucatán (Mexico). Wave information from a 30-year wave hindcast is validated with in situ measurements at 8 m water depth. The maximum dissimilarity algorithm is employed for the selection of 600 representative cases, encompassing different combinations of wave characteristics and tidal level. The selected cases are propagated from 8 m water depth to the shore using the coupling of a third-generation wave model and a phase-resolving non-hydrostatic nonlinear shallow-water equation model. Extreme wave run-up, R2%, is estimated for the simulated cases and can be further employed to reconstruct the 30-year time series using an interpolation algorithm. Downscaling results show run-up saturation during more energetic wave conditions and modulation owing to tides. The latter suggests that the R2% can be parameterized using a hyperbolic-like formulation with dependency on both wave height and tidal level. The new parametric formulation is in agreement with the downscaling results (r2 = 0.78), allowing a fast calculation of wave-induced extreme water levels at this location. Finally, an assessment of beach vulnerability to wave-induced extreme water levels is conducted at the study area by employing the two approaches (reconstruction/parameterization) and a storm impact scale. The 30-year extreme water level hindcast allows the calculation of beach vulnerability as a function of return periods. It is shown that the downscaling-derived parameterization provides reasonable results as compared with the numerical approach. This methodology can be extended to other locations and can be further improved by incorporating the storm surge contributions to the extreme water level.

  9. Runup parameterization and beach vulnerability assessment on a barrier island: a downscaling approach

    NASA Astrophysics Data System (ADS)

    Medellín, G.; Brinkkemper, J. A.; Torres-Freyermuth, A.; Appendini, C. M.; Mendoza, E. T.; Salles, P.

    2015-05-01

    We present a downscaling approach for the study of wave-induced extreme water levels at a location on a barrier island in Yucatan (Mexico). Wave information from a 30 year wave hindcast is validated with in situ measurements at 8 m water depth. The Maximum Dissimilarity Algorithm is employed for the selection of 600 representative cases, encompassing different wave characteristics and tidal level combinations. The selected cases are propagated from 8 m water depth till the shore using the coupling of a third-generation wave model and a phase-resolving non-hydrostatic Nonlinear Shallow Water Equations model. Extreme wave runup, R2%, is estimated for the simulated cases and can be further employed to reconstruct the 30 year period using an interpolation algorithm. Downscaling results show runup saturation during more energetic wave conditions and modulation owing to tides. The latter suggests that the R2% can be parameterized using a hyperbolic-like formulation with dependency on both wave height and tidal level. The new parametric formulation is in agreement with the downscaling results (r2 = 0.78), allowing a fast calculation of wave-induced extreme water levels at this location. Finally, an assessment of beach vulnerability to wave-induced extreme water level is conducted at the study area by employing the two approaches (reconstruction/parametrization) and a storm impact scale. The 30 year extreme water level hindcast allows the calculation of beach vulnerability as a function of return periods. It is shown that the downscaling-derived parameterization provides reasonable results as compared with the numerical approach. This methodology can be extended to other locations and can be further improved by incorporating the storm surge contributions to the extreme water level.

  10. Advanced Land Imager Assessment System

    NASA Technical Reports Server (NTRS)

    Chander, Gyanesh; Choate, Mike; Christopherson, Jon; Hollaren, Doug; Morfitt, Ron; Nelson, Jim; Nelson, Shar; Storey, James; Helder, Dennis; Ruggles, Tim; Kaita, Ed; Levy, Raviv; Ong, Lawrence; Markham, Brian; Schweiss, Robert

    2008-01-01

    The Advanced Land Imager Assessment System (ALIAS) supports radiometric and geometric image processing for the Advanced Land Imager (ALI) instrument onboard NASA s Earth Observing-1 (EO-1) satellite. ALIAS consists of two processing subsystems for radiometric and geometric processing of the ALI s multispectral imagery. The radiometric processing subsystem characterizes and corrects, where possible, radiometric qualities including: coherent, impulse; and random noise; signal-to-noise ratios (SNRs); detector operability; gain; bias; saturation levels; striping and banding; and the stability of detector performance. The geometric processing subsystem and analysis capabilities support sensor alignment calibrations, sensor chip assembly (SCA)-to-SCA alignments and band-to-band alignment; and perform geodetic accuracy assessments, modulation transfer function (MTF) characterizations, and image-to-image characterizations. ALIAS also characterizes and corrects band-toband registration, and performs systematic precision and terrain correction of ALI images. This system can geometrically correct, and automatically mosaic, the SCA image strips into a seamless, map-projected image. This system provides a large database, which enables bulk trending for all ALI image data and significant instrument telemetry. Bulk trending consists of two functions: Housekeeping Processing and Bulk Radiometric Processing. The Housekeeping function pulls telemetry and temperature information from the instrument housekeeping files and writes this information to a database for trending. The Bulk Radiometric Processing function writes statistical information from the dark data acquired before and after the Earth imagery and the lamp data to the database for trending. This allows for multi-scene statistical analyses.

  11. Ex vivo Evans blue assessment of the blood brain barrier in three breast cancer brain metastasis models.

    PubMed

    Do, John; Foster, Deshka; Renier, Corinne; Vogel, Hannes; Rosenblum, Sahar; Doyle, Timothy C; Tse, Victor; Wapnir, Irene

    2014-02-01

    The limited entry of anticancer drugs into the central nervous system represents a special therapeutic challenge for patients with brain metastases and is primarily due to the blood brain barrier (BBB). Albumin-bound Evans blue (EB) dye is too large to cross the BBB but can grossly stain tissue blue when the BBB is disrupted. The course of tumor development and the integrity of the BBB were studied in three preclinical breast cancer brain metastasis (BCBM) models. A luciferase-transduced braintropic clone of MDA-231 cell line was used. Nude mice were subjected to stereotactic intracerebral inoculation, mammary fat pad-derived tumor fragment implantation, or carotid artery injections. EB was injected 30 min prior to euthanasia at various timepoints for each of the BCBM model animals. Serial bioluminescent imaging demonstrated exponential tumor growth in all models. Carotid BCBM appeared as diffuse multifocal cell clusters. EB aided the localization of metastases ex vivo. Tumor implants stained blue at 7 days whereas gross staining was not evident until day 14 in the stereotactic model and day 28 for the carotid model. EB assessment of the integrity of the BBB provides useful information relevant to drug testing in preclinical BCBM models.

  12. Launcher Systems Development Cost: Behavior, Uncertainty, Influences, Barriers and Strategies for Reduction

    NASA Technical Reports Server (NTRS)

    Shaw, Eric J.

    2001-01-01

    This paper will report on the activities of the IAA Launcher Systems Economics Working Group in preparations for its Launcher Systems Development Cost Behavior Study. The Study goals include: improve launcher system and other space system parametric cost analysis accuracy; improve launcher system and other space system cost analysis credibility; and provide launcher system and technology development program managers and other decisionmakers with useful information on development cost impacts of their decisions. The Working Group plans to explore at least the following five areas in the Study: define and explain development cost behavior terms and concepts for use in the Study; identify and quantify sources of development cost and cost estimating uncertainty; identify and quantify significant influences on development cost behavior; identify common barriers to development cost understanding and reduction; and recommend practical, realistic strategies to accomplish reductions in launcher system development cost.

  13. Launcher Systems Development Cost: Behavior, Uncertainty, Influences, Barriers and Strategies for Reduction

    NASA Technical Reports Server (NTRS)

    Shaw, Eric J.

    2001-01-01

    This paper will report on the activities of the IAA Launcher Systems Economics Working Group in preparations for its Launcher Systems Development Cost Behavior Study. The Study goals include: improve launcher system and other space system parametric cost analysis accuracy; improve launcher system and other space system cost analysis credibility; and provide launcher system and technology development program managers and other decisionmakers with useful information on development cost impacts of their decisions. The Working Group plans to explore at least the following five areas in the Study: define and explain development cost behavior terms and concepts for use in the Study; identify and quantify sources of development cost and cost estimating uncertainty; identify and quantify significant influences on development cost behavior; identify common barriers to development cost understanding and reduction; and recommend practical, realistic strategies to accomplish reductions in launcher system development cost.

  14. Chronic systemic IL-1β exacerbates central neuroinflammation independently of the blood-brain barrier integrity.

    PubMed

    Murta, Verónica; Farías, María Isabel; Pitossi, Fernando Juan; Ferrari, Carina Cintia

    2015-01-15

    Peripheral circulating cytokines are involved in immune to brain communication and systemic inflammation is considered a risk factor for flaring up the symptoms in most neurodegenerative diseases. We induced both central inflammatory demyelinating lesion, and systemic inflammation with an interleukin-1β expressing adenovector. The peripheral pro-inflammatory stimulus aggravated the ongoing central lesion independently of the blood-brain barrier (BBB) integrity. This model allows studying the role of specific molecules and cells (neutrophils) from the innate immune system, in the relationship between central and peripheral communication, and on relapsing episodes of demyelinating lesions, along with the role of BBB integrity. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Integrity of the alveolar-capillary barrier and alveolar surfactant system in smokers.

    PubMed Central

    Schmekel, B; Bos, J A; Khan, A R; Wohlfart, B; Lachmann, B; Wollmer, P

    1992-01-01

    BACKGROUND: The permeability of the alveolar-capillary barrier to technetium-99m labelled diethylenetriamine pentaacetate (99mTc DTPA) is known to be greatly increased in smokers, but the underlying mechanism is poorly understood. Abnormal permeability of the alveolar epithelium as well as impaired surfactant function has been suggested. The purpose of this study was to examine transudation of urea and albumin into the alveoli and alveolar surfactant function in smokers and non-smokers and to relate these variables to the rate of alveolar-capillary transfer of 99mTc DTPA. METHODS: Standardised bronchoalveolar lavage was performed and the yield of urea and albumin measured in the lavage fluid. The integrity of the alveolar surfactant system was assessed by measurement of the surface activity and of the yield of phospholipids in alveolar lavage fluid. RESULTS: The mean decay constant for the pulmonary clearance of 99mTc DTPA was 0.028/min in the smokers and 0.009/min in the non-smokers. The recovery of albumin and urea in alveolar lavage fluid was very similar in the two groups. The surface activity of alveolar lavage fluid was lower in smokers than in non-smokers (minimum surface tension 37.9 versus 28.6 mN/m) and the yield of phospholipids was reduced (2.08 versus 3.86 mg). The rate constant for the pulmonary clearance of 99mTc DTPA correlated with the yield of phospholipids at bronchoalveolar lavage. CONCLUSIONS: The study shows that increased alveolar-capillary transfer of 99mTc DTPA in smokers is not accompanied by increased transudation of small or large molecules into the alveoli. The findings support the hypothesis that increased clearance of 99mTc DTPA in smokers is related to surfactant dysfunction. PMID:1412116

  16. Facilitators and Barriers in the Use of a Checklist by Insurance Physicians during Work Ability Assessments in Depressive Disorder

    PubMed Central

    Blok, Sebastiaan; Slebus, Frans G; Sluiter, Judith K; Frings-Dresen, Monique HW

    2011-01-01

    Objectives Depressive disorder (DD) is a complex disease, and the assessment of work ability in patients with DD is also complicated. The checklist depression (CDp) has recently been developed to support such work ability assessments and has been recommended for implementation in insurance medicine, starting with an analysis of the organisational and social contexts. The aim of this study was to identify the potential facilitators and barriers in the use of the CDp by insurance physicians (IPs) during work ability assessments of employees on sick leave due to DD. Methods A qualitative research was conducted based on semi-structured interviews. The participants were IPs with at least one year of work experience in performing work ability assessments. The interviews were audiotaped, transcribed and analysed qualitatively. Results Ten IPs (7 males, 3 females; mean 53 years) were interviewed. Important facilitators, which emerged for use of the CDp, were an oral introduction for colleagues and staff, support from management, valuing the increased transparency in work ability assessments with using the CDp, having adequate time for assessments as well as modification of the appearance (colour, plasticised form) and content (clarifying aspects of the examples) of the assessment tool. The fear of the loss of autonomy, lack of added value of the CDp, high workload, inadequate instructions and lack of time were mentioned as barriers. Conclusion Adequate introduction to the use of CDp and the fear of the loss of autonomy of IPs need special attention in planning its implementation. PMID:22953217

  17. CAIS. Condition Assessment Information System

    SciTech Connect

    Oak, J.C.

    1996-09-30

    CAIS is used by Architects and Engineers to gather facility condition assessment data. This data consist of architectural, civil, structural, electrical, and mechanical systems and components that are a part of the inspected facility. Data is collected using a hand-held, pen-based computer system which is preprogrammed for detailed inventories of individual components. The program is deficiency based for collecting data for repair and replacement observations. Observations are recorded on checklists preformatted to individual site needs, allowing for comments on unusual conditions to be documented on site. Data is transferred to a central database, where it can be reviewed, costed, and reported on using different scenarios. Information can be transferred to the DOE operations offices as well as to the DOE FIMS database for each site.

  18. General practitioners' views on perceived and actual gains, benefits and barriers associated with the implementation of an Australian health assessment for people with intellectual disability.

    PubMed

    Lennox, N G; Brolan, C E; Dean, J; Ware, R S; Boyle, F M; Taylor Gomez, M; van Dooren, K; Bain, C

    2013-10-01

    Health assessments for people with intellectual disability have been implemented in the UK, New Zealand and Australia, and have led to improved health outcomes. The Comprehensive Health Assessment Program (CHAP) has been shown to improve the health of people with intellectual disability. Similar to other health assessments, it is designed to address healthcare needs, many of which are often overlooked in this population, through better communication between the general practitioner (GP), support worker and the person with intellectual disability. This study investigates GP views of the perceived and actual benefits, gains and barriers associated with its uptake and use in practice. As part of a larger randomised controlled trial of the CHAP, 46 GPs in Queensland, Australia, completed two telephone interviews that included open-ended questions about their perceptions of the health assessment. The GPs were enrolled in the intervention arm of the trial. Interviews took place at commencement and conclusion of the trial to gain the views of GPs as they experienced using the CHAP. Thematic analysis was used to identify key themes and patterns from the GP responses. Four themes were identified: better healthcare and uncertain benefits captured GP perceptions of the potential gains associated with use of the CHAP, while two further themes, organisational barriers in the general practice setting and engagement across the healthcare triad highlighted strengths and barriers related to implementation. Anticipated concerns about time raised by GPs at commencement of the trial were borne out in practice, but concerns about communication and cooperation of people with disabilities were not. Matters associated with support worker engagement emerged as an area of concern. GPs perceive the CHAP as a structured and comprehensive approach to the detection of medical problems as well as an aid in overcoming communication barriers between the doctor and the person with disability. Our

  19. Nanoparticles and blood-brain barrier: the key to central nervous system diseases.

    PubMed

    Domínguez, Alazne; Suárez-Merino, Blanca; Goñi-de-Cerio, Felipe

    2014-01-01

    Major central nervous system disorders represent a significant and worldwide public health problem. In fact, the therapeutic success of many pharmaceuticals developed to treat central nervous system diseases is still moderate, since the blood-brain barrier (BBB) limits the access of systemically administered compounds to the brain. Therefore, they require the application of a large total dose of a drug, and cause numerous toxic effects. The development of nanotechnological systems are useful tools to deliver therapeutics and/or diagnostic probes to the brain due to nanocarriers having the potential to improve the therapeutic effect of drugs and to reduce their side effects. This review provides a brief overview of the variety of carriers employed for central nervous system drug and diagnostic probes delivery. Further, this paper focuses on the novel nanocarriers developed to enhance brain delivery across the blood-brain barrier. Special attention is paid to liposomes, micelles, polymeric and lipid-based nanoparticles, dendrimers and carbon nanotubes. The recent developments in nanocarrier implementation through size/charge optimization and surface modifications (PEGylation, targeting delivery, and coating with surfactants) have been discussed. And a detailed description of the nanoscaled pharmaceutical delivery devices employed for the treatment of central nervous system disorders have also been defined. The aim of the review is to evaluate the nanotechnology-based drug delivery strategies to treat different central nervous system disorders.

  20. Mobile munitions assessment system development

    SciTech Connect

    Rowe, L.C.; Watts, K.D.; Jorgensen, C.L.

    1996-05-01

    The United States has been involved in the development, testing, storage and disposal of chemical weapons since World War I. As a result, there are numerous sites which contain the presence of chemical warfare materiel. This materiel is in the form of buried surplus munitions, munitions that did not detonate during testing and other forms. These items pose a significant human health and environmental hazard and must be disposed of properly. The US Army was tasked by the Department of Defense with the remediation of all non-stockpile chemical warfare materiel. To help comply with this tasking, the Army Project Manager for Nonstockpile Chemical Materiel is sponsoring the development of a Mobile Munitions Assessment System (MMAS). The system is being developed by the Idaho National Engineering Laboratory and Dugway Proving Ground. The purpose of the system is to inspect suspect munitions and containers, identify the fill, evaluate the fuzing and firing train and analyze samples from the surrounding area to determine if chemical warfare materiel is present. The information gained from the application of the MMAS and other systems is intended to be used to establish the best method to handle and dispose of a given munition and its contents.

  1. Assessing Global Water System Research

    NASA Astrophysics Data System (ADS)

    Braimoh, Ademola K.; Craswell, Eric T.

    2006-04-01

    Rapid growth of global change science has led to improved knowledge about interdependencies in the global water cycle and recognition that the global water system consists of physical, human, and biogeochemical components [Vörösmarty et al., 2004]. Traditionally, water research is spread over a number of scientific disciplines. However, for water science to effectively inform policy for sustainable water management, research about the dynamics of water in the context of global change needs to be holistic, must integrate the existing knowledge base, and should synthesize knowledge about how the interactions between nature and society at various scales are affecting the global water system. This article assesses the level of interdisciplinarity in water science programs by comparing the activities of international waterrelated projects with the Global Water System Project (GWSP) activity profile (http://www.gwsp.org). The GWSP is a project of the Earth System Science Partnership (ESSP) comprising the International Geosphere-Biosphere Programme (http:// www.igbp.kva.se/cgi-bin/php/frameset.php), the International Human Dimension Programme on Global Environmental Change (www.ihdp.org), the World Climate Research Programme (http://www.wmo.ch/web/wcrp/wcrp-home.html), and the DIVERSITAS international program on biodiversity science (http://www.diversitasinternational.org/). GWSP's attributes include its scientific and policy-informing orientation, global perspective, integrative and interdisciplinary approach, and multitemporal investigation of human impacts on water resources.

  2. A ring barrier-based migration assay to assess cell migration in vitro.

    PubMed

    Das, Asha M; Eggermont, Alexander M M; ten Hagen, Timo L M

    2015-06-01

    Cell migration is a key feature of virtually every biological process, and it can be studied in a variety of ways. Here we outline a protocol for the in vitro study of cell migration using a ring barrier-based assay. A 'barrier' is inserted in the culture chamber, which prevents cells from entering a defined area. Cells of interest are seeded around this barrier, and after the formation of a peripheral monolayer the barrier is removed and migration into the cell-free area is monitored. This assay is highly reproducible and convenient to perform, and it allows the deduction of several parameters of migration, including total and effective migration, velocity and cell polarization. An advantage of this assay over the conventional scratch assay is that the cells move over an unaltered and virgin surface, and thus the effect of matrix components on cell migration can be studied. In addition, the cells are not harmed at the onset of the assay. Through computer automation, four individual barrier assays can be monitored at the same time. The procedure can be used in a 12-well standard plate allowing higher throughput, or it can be modified to perform invasion assays. The basic procedure takes 2-3 d to complete.

  3. Influences of specific ions in groundwater on concrete degradation in subsurface engineered barrier system.

    PubMed

    Lin, Wen-Sheng; Liu, Chen-Wuing; Li, Ming-Hsu

    2016-01-01

    Many disposal concepts currently show that concrete is an effective confinement material used in engineered barrier systems (EBS) at a number of low-level radioactive waste (LLW) disposal sites. Cement-based materials have properties for the encapsulation, isolation, or retardation of a variety of hazardous contaminants. The reactive chemical transport model of HYDROGEOCHEM 5.0 was applied to simulate the effect of hydrogeochemical processes on concrete barrier degradation in an EBS which has been proposed to use in the LLW disposal site in Taiwan. The simulated results indicated that the main processes that are responsible for concrete degradation are the species induced from hydrogen ion, sulfate, and chloride. The EBS with the side ditch drainage system effectively discharges the infiltrated water and lowers the solute concentrations that may induce concrete degradation. The redox processes markedly influence the formations of the degradation materials. The reductive environment in the EBS reduces the formation of ettringite in concrete degradation processes. Moreover, the chemical conditions in the concrete barriers maintain an alkaline condition after 300 years in the proposed LLW repository. This study provides a detailed picture of the long-term evolution of the hydrogeochemical environment in the proposed LLW disposal site in Taiwan.

  4. Effects of sea-level rise on barrier island groundwater system dynamics: ecohydrological implications

    USGS Publications Warehouse

    Masterson, John P.; Fienen, Michael N.; Thieler, E. Robert; Gesch, Dean B.; Gutierrez, Benjamin T.; Plant, Nathaniel G.

    2014-01-01

    We used a numerical model to investigate how a barrier island groundwater system responds to increases of up to 60 cm in sea level. We found that a sea-level rise of 20 cm leads to substantial changes in the depth of the water table and the extent and depth of saltwater intrusion, which are key determinants in the establishment, distribution and succession of vegetation assemblages and habitat suitability in barrier islands ecosystems. In our simulations, increases in water-table height in areas with a shallow depth to water (or thin vadose zone) resulted in extensive groundwater inundation of land surface and a thinning of the underlying freshwater lens. We demonstrated the interdependence of the groundwater response to island morphology by evaluating changes at three sites. This interdependence can have a profound effect on ecosystem composition in these fragile coastal landscapes under long-term changing climatic conditions.

  5. Symmetric splitting for the system 32S+238U at energies near and below the barrier

    NASA Astrophysics Data System (ADS)

    Freifelder, R.; Braun-Munzinger, P.; Deyoung, P.; Schicker, R.; Sen, S.; Stachel, J.

    1987-06-01

    The total capture cross section for the system 32S+238U has been measured at energies from 0.93 to 1.08 times the s-wave interaction barrier by detecting coincident fission fragments following full momentum transfer reactions. The subbarrier cross section cannot be reproduced by a one-dimensional barrier penetration model. Using a quantum mechanical coupled channels model, good agreement is obtained. The measured angular distributions of fission fragments were compared to the predictions of saddle and scission point transition state theory. Saddle point transition state model calculations fail to reproduce the data, while scission point transition state calculations are in agreement with their qualitative trend. Evidence for nonequilibrium processes is presented.

  6. Coastal Bays and Sea Level Rise: a long term analysis of Chincoteague Bay Barrier Island System.

    NASA Astrophysics Data System (ADS)

    Kumar, A.; Murry, N.

    2016-02-01

    The physical setting and dynamic processes of Coastal Bays provide the foundation for a complex and productive ecosystem. Stresses to the Coastal Bays system, and management challenges for the coming century, are related largely to the increasing pace of development in the coastal zone, and the prospect of accelerated sea level rise driven by global warming. The Chincoteague Bay, ideally located behind barrier islands support a critical habitat for migratory shorebirds and waterfowl, many important commercial and recreational fishing and numerous rare and threatened plant and animal species. Against this background, a 50-100 year storm can exert a powerful influence by reshaping and restructuring the barrier islands and Coastal Bays. In this study, we plan to illustrate how Hurricane Sandy exerted such an influence on the Chincoteague Bay. Using long-term tidal data, we will show how storm surges from Hurricane Sandy inundated and altered low lying areas of the region.

  7. Changes in villus-like projections of corneocytes from the facial skin in normal infants with or without infantile eczema; useful parameter to assess barrier function.

    PubMed

    Naoko, Ota; Satoshi, Hirakawa; Fukuyoshi, Mori; Mitsuyoshi, Honda

    2013-11-01

    Skin barrier function changes rapidly during the first year of life in infants. Measuring skin barrier function in infants is difficult because of the burden on patients and their parents or guardians. A simple method for assessing barrier function in infants that can be performed quickly and would enable swift treatment and skin care management. We used laser microscopy to investigate villus-like projections (VPs) observed on the lower surface of corneocytes obtained on tape strips from 18 normal Japanese infants at the ages of 1, 3, and 6 months. We also performed transepidermal water loss and corneocyte size measurements. A dermatologist clinically assessed the cutaneous findings. We rapidly measured skin barrier function changes during the first 6 months of life in infants. During the study period, very slight erythema and pityriasis were the primary reasons for skin rash, which were generally most severe at 3 months. The results showed that barrier function declined at approximately 3 months of age in nearly all subjects. Therefore, we found that normal barrier function of infantile skin becomes temporarily impaired after birth. We conclude that even in patients with very mild skin rashes, multiple objective indices of skin barrier function deteriorate simultaneously. Observation of VPs on the surface of corneocytes using laser microscopy is a rapid, painless, and effective method of monitoring skin barrier function in infants, and VP score offers a useful index for assessing barrier function. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Oxidation and degradation of a plasma-sprayed thermal barrier coating system

    SciTech Connect

    Haynes, J.A.; Ferber, M.K.; Porter, W.D.

    1996-04-01

    The isothermal oxidation behavior of thermal barrier coating (TBC) specimens consisting of single-crystal superalloy substrates, vacuum plasma-sprayed Ni-22Cr-10Al-1Y bond coatings and air plasma-sprayed 7.5 wt.% yttria stabilized zirconia top coatings was evaluated by thermogravimetric analysis at 1150{degrees}C for up to 200 hours. Coating durability was assessed by furnace cycling at 1150{degrees}C. Coatings and reaction products were identified by x-ray diffraction, field-emission scanning electron microscopy and energy dispersive spectroscopy.

  9. Development of backfill material as an engineered barrier in the waste package system- Interim topical report

    SciTech Connect

    Wheelwright, E.J.; Hodges, F.N.; Bray, L.A.; Westsik, J.H. Jr.; Lester, D.H.; Nakai, T.L.; Spaeth, M.E.; Stula, R.T.

    1981-09-01

    A backfill barrier, emplaced between the containerized waste and the host rock, can both protect the other engineered barriers and act as a primary barrier to the release of radionuclides from the waste package. Attributes that a backfill should provide in order to carry out its required function have been identified. Primary attributes are those that have a direct effect upon the release and transport of radionuclides from the waste package. Supportive attributes do not directly affect radionuclide release but are necessary to support the primary attributes. The primary attributes, in order of importance, are: minimize (retard or exclude) the migration of ground water between the host rock and the waste canister system; retard the migration of selected chemical species (corrosive species and radionuclides) in the ground water; control the Eh and pH of the ground water within the waste-package environment. The supportive attributes are: self-seal any cracks or discontinuities in the backfill or interfacing host geology; retain performance properties at all repository temperatures; retain peformance properties during and after receiving repository levels of gamma radiation; conduct heat from the canister system to the host geology; retain mechanical properties and provide resistance to applied mechanical forces; retain morphological stability and compatibility with structural barriers and with the host geology for required period of time. Screening and selection of candidate backfill materials has resulted in a preliminary list of materials for testing. Primary emphasis has been placed on sodium and calcium bentonites and zeolites used in conjunction with quartz sand or crushed host rock. Preliminary laboratory studies have concentrated on permeability, sorption, swelling pressure, and compaction properties of candidate backfill materials.

  10. Prezygotic Barriers to Hybridization in Marine Broadcast Spawners: Reproductive Timing and Mating System Variation

    PubMed Central

    Monteiro, Carla A.; Serrão, Ester A.; Pearson, Gareth A.

    2012-01-01

    Sympatric assemblages of congeners with incomplete reproductive barriers offer the opportunity to study the roles that ecological and non-ecological factors play in reproductive isolation. While interspecific asynchrony in gamete release and gametic incompatibility are known prezygotic barriers to hybridization, the role of mating system variation has been emphasized in plants. Reproductive isolation between the sibling brown algal species Fucus spiralis, Fucus guiryi (selfing hermaphrodite) and Fucus vesiculosus (dioecious) was studied because they form hybrids in parapatry in the rocky intertidal zone, maintain species integrity over a broad geographic range, and have contrasting mating systems. We compared reproductive synchrony (spawning overlap) between the three species at several temporal scales (yearly/seasonal, semilunar/tidal, and hourly during single tides). Interspecific patterns of egg release were coincident at seasonal (single peak in spring to early summer) to semilunar timescales. Synthesis of available data indicated that spawning is controlled by semidiurnal tidal and daily light-dark cues, and not directly by semilunar cycles. Importantly, interspecific shifts in timing detected at the hourly scale during single tides were consistent with a partial ecological prezygotic hybridization barrier. The species displayed patterns of gamete release consistent with a power law distribution, indicating a high degree of reproductive synchrony, while the hypothesis of weaker selective constraints for synchrony in selfing versus outcrossing species was supported by observed spawning in hermaphrodites over a broader range of tidal phase than in outcrossers. Synchronous gamete release is critical to the success of external fertilization, while high-energy intertidal environments may offer only limited windows of reproductive opportunity. Within these windows, however, subtle variations in reproductive timing have evolved with the potential to form ecological

  11. Prezygotic barriers to hybridization in marine broadcast spawners: reproductive timing and mating system variation.

    PubMed

    Monteiro, Carla A; Serrão, Ester A; Pearson, Gareth A

    2012-01-01

    Sympatric assemblages of congeners with incomplete reproductive barriers offer the opportunity to study the roles that ecological and non-ecological factors play in reproductive isolation. While interspecific asynchrony in gamete release and gametic incompatibility are known prezygotic barriers to hybridization, the role of mating system variation has been emphasized in plants. Reproductive isolation between the sibling brown algal species Fucus spiralis, Fucus guiryi (selfing hermaphrodite) and Fucus vesiculosus (dioecious) was studied because they form hybrids in parapatry in the rocky intertidal zone, maintain species integrity over a broad geographic range, and have contrasting mating systems. We compared reproductive synchrony (spawning overlap) between the three species at several temporal scales (yearly/seasonal, semilunar/tidal, and hourly during single tides). Interspecific patterns of egg release were coincident at seasonal (single peak in spring to early summer) to semilunar timescales. Synthesis of available data indicated that spawning is controlled by semidiurnal tidal and daily light-dark cues, and not directly by semilunar cycles. Importantly, interspecific shifts in timing detected at the hourly scale during single tides were consistent with a partial ecological prezygotic hybridization barrier. The species displayed patterns of gamete release consistent with a power law distribution, indicating a high degree of reproductive synchrony, while the hypothesis of weaker selective constraints for synchrony in selfing versus outcrossing species was supported by observed spawning in hermaphrodites over a broader range of tidal phase than in outcrossers. Synchronous gamete release is critical to the success of external fertilization, while high-energy intertidal environments may offer only limited windows of reproductive opportunity. Within these windows, however, subtle variations in reproductive timing have evolved with the potential to form ecological

  12. Assessing the additive risks of PSII herbicide exposure to the Great Barrier Reef.

    PubMed

    Lewis, Stephen E; Schaffelke, Britta; Shaw, Melanie; Bainbridge, Zoë T; Rohde, Ken W; Kennedy, Karen; Davis, Aaron M; Masters, Bronwyn L; Devlin, Michelle J; Mueller, Jochen F; Brodie, Jon E

    2012-01-01

    Herbicide residues have been measured in the Great Barrier Reef lagoon at concentrations which have the potential to harm marine plant communities. Monitoring on the Great Barrier Reef lagoon following wet season discharge show that 80% of the time when herbicides are detected, more than one are present. These herbicides have been shown to act in an additive manner with regards to photosystem-II inhibition. In this study, the area of the Great Barrier Reef considered to be at risk from herbicides is compared when exposures are considered for each herbicide individually and also for herbicide mixtures. Two normalisation indices for herbicide mixtures were calculated based on current guidelines and PSII inhibition thresholds. The results show that the area of risk for most regions is greatly increased under the proposed additive PSII inhibition threshold and that the resilience of this important ecosystem could be reduced by exposure to these herbicides.

  13. Effect of radiant barriers and attic ventilation on residential attics and attic duct systems: New tools for measuring and modeling

    SciTech Connect

    Petrie, T.W.; Childs, P.W.; Christian, J.E.; Wilkes, K.E.

    1998-07-01

    A simple duct system was installed in an attic test module for a large scale climate simulator at a US national laboratory. The goal of the tests and subsequent modeling was to develop an accurate method of assessing duct system performance in the laboratory, enabling limiting conditions to be imposed at will and results to be applied to residential attics with attic duct systems. Steady-state tests were done at a severe summer and a mild winter condition. In all tests the roof surface was heated above ambient air temperatures by infrared lights. The attic test module first included then did not include the duct system. Attic ventilation from eave vents to a ridge vent was varied from none to values achievable by a high level of power ventilation. A radiant barrier was attached to the underside of the roof deck, both with and without the duct system in place. Tests were also done without the radiant barrier, both with and without the duct system. When installed, the insulated ducts ran along the floor of the attic, just above the attic insulation and along the edge of the attic near the eaves and one gable. These tests in a climate simulator achieved careful control and reproducibility of conditions. This elucidated dependencies that would otherwise be hidden by variations in uncontrolled variables. Based on the comparisons with the results of the tests at the mild winter condition and the severe summer condition, model predictions for attic air and insulation temperatures should be accurate within {+-} 10 F ({+-} 6 C). This is judged adequate for design purposes and could be better when exploring the effect of changes in attic and duct parameters at fixed climatic conditions.

  14. Approaches to formalization of the informal waste sector into municipal solid waste management systems in low- and middle-income countries: Review of barriers and success factors.

    PubMed

    Aparcana, Sandra

    2017-03-01

    The Municipal Solid Waste Management (MSWM) sector represents a major challenge for low-and middle-income countries due to significant environmental and socioeconomic issues involving rapid urbanization, their MSWM systems, and the existence of the informal waste sector. Recognizing its role, several countries have implemented various formalization measures, aiming to address the social problems linked to this sector. However, regardless of these initiatives, not all attempts at formalization have proved successful due to the existence of barriers preventing their implementation in the long term. Along with this, there is a frequent lack of knowledge or understanding regarding these barriers and the kind of measures that may enable formalization, thereby attaining a win-win situation for all the stakeholders involved. In this context, policy- and decision-makers in the public and private sectors are frequently confronted with the dilemma of finding workable approaches to formalization, adjusted to their particular MSWM contexts. Building on the review of frequently implemented approaches to formalization, including an analysis of the barriers to and enabling measures for formalization, this paper aims to address this gap by explaining to policy- and decision-makers, and to waste managers in the private sector, certain dynamics that can be observed and that should be taken into account when designing formalization strategies that are adapted to their particular socioeconomic and political-institutional context. This includes possible links between formalization approaches and barriers, the kinds of barriers that need to be removed, and enabling measures leading to successful formalization in the long term. This paper involved a literature review of common approaches to formalization, which were classified into three categories: (1) informal waste workers organized in associations or cooperatives; (2) organized in CBOs or MSEs; and (3) contracted as individual

  15. Critical infrastructure systems of systems assessment methodology.

    SciTech Connect

    Sholander, Peter E.; Darby, John L.; Phelan, James M.; Smith, Bryan; Wyss, Gregory Dane; Walter, Andrew; Varnado, G. Bruce; Depoy, Jennifer Mae

    2006-10-01

    Assessing the risk of malevolent attacks against large-scale critical infrastructures requires modifications to existing methodologies that separately consider physical security and cyber security. This research has developed a risk assessment methodology that explicitly accounts for both physical and cyber security, while preserving the traditional security paradigm of detect, delay, and respond. This methodology also accounts for the condition that a facility may be able to recover from or mitigate the impact of a successful attack before serious consequences occur. The methodology uses evidence-based techniques (which are a generalization of probability theory) to evaluate the security posture of the cyber protection systems. Cyber threats are compared against cyber security posture using a category-based approach nested within a path-based analysis to determine the most vulnerable cyber attack path. The methodology summarizes the impact of a blended cyber/physical adversary attack in a conditional risk estimate where the consequence term is scaled by a ''willingness to pay'' avoidance approach.

  16. Dynamical systems probabilistic risk assessment

    SciTech Connect

    Denman, Matthew R.; Ames, Arlo Leroy

    2014-03-01

    Probabilistic Risk Assessment (PRA) is the primary tool used to risk-inform nuclear power regulatory and licensing activities. Risk-informed regulations are intended to reduce inherent conservatism in regulatory metrics (e.g., allowable operating conditions and technical specifications) which are built into the regulatory framework by quantifying both the total risk profile as well as the change in the risk profile caused by an event or action (e.g., in-service inspection procedures or power uprates). Dynamical Systems (DS) analysis has been used to understand unintended time-dependent feedbacks in both industrial and organizational settings. In dynamical systems analysis, feedback loops can be characterized and studied as a function of time to describe the changes to the reliability of plant Structures, Systems and Components (SSCs). While DS has been used in many subject areas, some even within the PRA community, it has not been applied toward creating long-time horizon, dynamic PRAs (with time scales ranging between days and decades depending upon the analysis). Understanding slowly developing dynamic effects, such as wear-out, on SSC reliabilities may be instrumental in ensuring a safely and reliably operating nuclear fleet. Improving the estimation of a plant's continuously changing risk profile will allow for more meaningful risk insights, greater stakeholder confidence in risk insights, and increased operational flexibility.

  17. Regulatory barriers to equity in a health system in transition: a qualitative study in Bulgaria

    PubMed Central

    2011-01-01

    Background Health reforms in Bulgaria have introduced major changes to the financing, delivery and regulation of health care. As in many other countries of Central and Eastern Europe, these included introducing general practice, establishing a health insurance system, reorganizing hospital services, and setting up new payment mechanisms for providers, including patient co-payments. Our study explored perceptions of regulatory barriers to equity in Bulgarian child health services. Methods 50 qualitative in-depth interviews with users, providers and policy-makers concerned with child health services in Bulgaria, conducted in two villages, one town of 70,000 inhabitants, and the capital Sofia. Results The participants in our study reported a variety of regulatory barriers which undermined the principles of equity and, as far as the health insurance system is concerned, solidarity. These included non-participation in the compulsory health insurance system, informal payments, and charging user fees to exempted patients. The participants also reported seemingly unnecessary treatments in the growing private sector. These regulatory failures were associated with the fast pace of reforms, lack of consultation, inadequate public financing of the health system, a perceived "commercialization" of medicine, and weak enforcement of legislation. A recurrent theme from the interviews was the need for better information about patient rights and services covered by the health insurance system. Conclusions Regulatory barriers to equity and compliance in daily practice deserve more attention from policy-makers when embarking on health reforms. New financing sources and an increasing role of the private sector need to be accompanied by an appropriate and enforceable regulatory framework to control the behavior of health care providers and ensure equity in access to health services. PMID:21923930

  18. Industrial energy systems and assessment opportunities

    NASA Astrophysics Data System (ADS)

    Barringer, Frank Leonard, III

    Industrial energy assessments are performed primarily to increase energy system efficiency and reduce energy costs in industrial facilities. The most common energy systems are lighting, compressed air, steam, process heating, HVAC, pumping, and fan systems, and these systems are described in this document. ASME has produced energy assessment standards for four energy systems, and these systems include compressed air, steam, process heating, and pumping systems. ASHRAE has produced an energy assessment standard for HVAC systems. Software tools for energy systems were developed for the DOE, and there are software tools for almost all of the most common energy systems. The software tools are AIRMaster+ and LogTool for compressed air systems, SSAT and 3E Plus for steam systems, PHAST and 3E Plus for process heating systems, eQUEST for HVAC systems, PSAT for pumping systems, and FSAT for fan systems. The recommended assessment procedures described in this thesis are used to set up an energy assessment for an industrial facility, collect energy system data, and analyze the energy system data. The assessment recommendations (ARs) are opportunities to increase efficiency and reduce energy consumption for energy systems. A set of recommended assessment procedures and recommended assessment opportunities are presented for each of the most common energy systems. There are many assessment opportunities for industrial facilities, and this thesis describes forty-three ARs for the seven different energy systems. There are seven ARs for lighting systems, ten ARs for compressed air systems, eight ARs for boiler and steam systems, four ARs for process heating systems, six ARs for HVAC systems, and four ARs for both pumping and fan systems. Based on a history of past assessments, average potential energy savings and typical implementation costs are shared in this thesis for most ARs. Implementing these ARs will increase efficiency and reduce energy consumption for energy systems in

  19. Asphalt emulsion radon barrier systems for uranium mill tailings: an overview of the technology

    SciTech Connect

    Baker, E.G.; Hartley, J.N.; Freeman, H.D.; Gates, T.E.; Nelson, D.A.; Dunning, R.L.

    1984-03-01

    Pacific Northwest Laboratory (PNL), under contract to the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) office, has developed an asphalt emulsion cover system to reduce the release of radon from uranium mill tailings. The system has been field tested at Grand Junction, Colorado. Results from laboratory and field tests indicate that this system is effective in reducing radon release to near-background levels (<2.5 pCi m/sup -2/s/sup -1/) and has the properties required for long-term effectiveness and stability. Engineering specifications have been developed, and analysis indicates that asphalt emulsion covers are cost-competitive with other cover systems. This report summarizes the technology for asphalt emulsion radon barrier systems. 59 references, 45 figures, 36 tables.

  20. Investigating Barriers to Tuberculosis Evaluation in Uganda Using Geographic Information Systems

    PubMed Central

    Ross, Jennifer M.; Cattamanchi, Adithya; Miller, Cecily R.; Tatem, Andrew J.; Katamba, Achilles; Haguma, Priscilla; Handley, Margaret A.; Lucian Davis, J.

    2015-01-01

    Reducing geographic barriers to tuberculosis (TB) care is a priority in high-burden countries where patients frequently initiate, but do not complete, the multi-day TB evaluation process. Using routine cross-sectional study from six primary-health clinics in rural Uganda from 2009 to 2012, we explored whether geographic barriers affect completion of TB evaluation among adults with unexplained chronic cough. We measured distance from home parish to health center and calculated individual travel time using a geographic information systems technique incorporating roads, land cover, and slope, and measured its association with completion of TB evaluation. In 264,511 patient encounters, 4,640 adults (1.8%) had sputum smear microscopy ordered; 2,783 (60%) completed TB evaluation. Median travel time was 68 minutes for patients with TB examination ordered compared with 60 minutes without (P < 0.010). Travel time differed between those who did and did not complete TB evaluation at only one of six clinics, whereas distance to care did not differ at any of them. Neither distance nor travel time predicted completion of TB evaluation in rural Uganda, although limited detail in road and village maps restricted full implementation of these mapping techniques. Better data are needed on geographic barriers to access clinics offering TB services to improve TB diagnosis. PMID:26217044

  1. Implementing a Lean Management System in Primary Care: Facilitators and Barriers From the Front Lines.

    PubMed

    Hung, Dorothy; Martinez, Meghan; Yakir, Maayan; Gray, Caroline

    2015-01-01

    Although Lean management techniques are increasingly used in health care to improve quality and reduce costs, lessons about how to successfully implement this approach on the front lines of care delivery are not well documented. In this study, we highlight key facilitators and barriers to implementing Lean among frontline primary care providers. This case study took place at a large, ambulatory care delivery system serving nearly 1 million patients. In-depth interviews were conducted with primary care physicians, staff, and administrators to identify key factors impacting Lean redesigns in primary care. Overall, staff engagement and performance management, sensitivity to the professional values and culture of medicine, and perceived adequacy of organizational resources were critical when introducing Lean changes. Specific drivers of change included empowerment of staff at all levels, visual display of performance metrics, and a culture of innovation and collaboration. Barriers included physician resistance to standardized work, difficulty transferring management responsibilities to non-physician staff, and time and staffing required for participating in improvement efforts. Although Lean offers a new approach to delivering care, the implementation process itself is both complex and crucial to success. Understanding early facilitators and barriers can maximize Lean's, potential to improve health care delivery.

  2. Monitoring long-term evolution of engineered barrier systems using magnets: Magnetic response.

    PubMed

    Rigonat, N; Isnard, O; Harley, S L; Butler, I B

    2018-01-05

    Remote and non-destructive monitoring of the stability and performance of Engineered Barrier Systems for Geological Disposal Facility of is gaining considerable importance in establishing the safety cases for Higher Activity Wastes disposal. This study offers an innovative use of mineral magnetism for monitoring groundwater saturation of the barrier. Four mixtures of permanent magnets (Nd-Fe-B, coated and uncoated; SmCo and AlNiCo) and bentonite were reacted for 4, 8 and 12 months with mildly-saline, high-pH leachates, representing the fluids saturating a time-evolved engineered barrier. Coupled hysteresis and thermomagnetic analyses demonstrate how Nd-Fe-B feature a time-dependent transition from square-like ferromagnetic to superparamagnetic loop via pot-bellied and wasp-waist loops, whereas SmCo and AlNiCo do not show so extensive corrosion-related variations of the intrinsic and extrinsic magnetic properties. This study allowed to identify magnetic materials suitable for shorter- (Nd-Fe-B) and longer-term (SmCo and AlNiCo) monitoring purposes. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Investigating Barriers to Tuberculosis Evaluation in Uganda Using Geographic Information Systems.

    PubMed

    Ross, Jennifer M; Cattamanchi, Adithya; Miller, Cecily R; Tatem, Andrew J; Katamba, Achilles; Haguma, Priscilla; Handley, Margaret A; Davis, J Lucian

    2015-10-01

    Reducing geographic barriers to tuberculosis (TB) care is a priority in high-burden countries where patients frequently initiate, but do not complete, the multi-day TB evaluation process. Using routine cross-sectional study from six primary-health clinics in rural Uganda from 2009 to 2012, we explored whether geographic barriers affect completion of TB evaluation among adults with unexplained chronic cough. We measured distance from home parish to health center and calculated individual travel time using a geographic information systems technique incorporating roads, land cover, and slope, and measured its association with completion of TB evaluation. In 264,511 patient encounters, 4,640 adults (1.8%) had sputum smear microscopy ordered; 2,783 (60%) completed TB evaluation. Median travel time was 68 minutes for patients with TB examination ordered compared with 60 minutes without (P < 0.010). Travel time differed between those who did and did not complete TB evaluation at only one of six clinics, whereas distance to care did not differ at any of them. Neither distance nor travel time predicted completion of TB evaluation in rural Uganda, although limited detail in road and village maps restricted full implementation of these mapping techniques. Better data are needed on geographic barriers to access clinics offering TB services to improve TB diagnosis.

  4. Barriers to the use of toxicogenomics data in human health risk assessment: A survey of Canadian risk assessors.

    PubMed

    Vachon, Julien; Campagna, Céline; Rodriguez, Manuel J; Sirard, Marc-André; Levallois, Patrick

    2017-04-01

    Regulatory agencies worldwide need to modernize human health risk assessment (HHRA) to meet challenges of the 21st century. Toxicogenomics is at the core of this improvement. Today, however, the use of toxicogenomics data in HHRA is very limited. The purpose of this survey was to identify barriers to the application of toxicogenomics data in HHRA by human health risk assessors. An online survey targeting Canadian risk assessors gathered information on their knowledge and perception of toxicogenomics, their current and future inclusion of toxicogenomics data in HHRA, and barriers to the use of such data. Twenty-nine (29) participants completed a questionnaire after 2 months of solicitation. The results show that the application of toxicogenomics data in Canada is marginal, with 85% of respondents reporting that they never or rarely used such data. Knowledge of toxicogenomics by Canadian risk assessors is also limited: about two-thirds of respondents (68%) were not at all or only slightly familiar with the concept. Lack of guidelines for toxicogenomics data interpretation, data quality assessment and on their use in HHRA, were found to be major barriers. In conclusion, there is a need for interventions aimed at facilitating the use of toxicogenomics data in HHRA, when available. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Sunscreen formulations may serve as additional water barrier on skin surface: a clinical assessment.

    PubMed

    Shyr, T; Ou-Yang, H

    2016-04-01

    Extended water exposure can cause stratum corneum swelling and a more porous skin barrier. People often wear water-resistant sunscreen formulations during extended period of water activities in the summer to protect skin from harmful UV rays. We wanted to evaluate whether sunscreen formulations can also serve as additional water barriers to help mitigate the disruption in stratum corneum caused by constant exposure to water. We conducted trans-epidermal water loss (TEWL) measurement in a controlled water patch (including salt and chlorine water) model and then applied this relevant model to study the effects of pre-treatments of sunscreen sprays and stick. We also conducted water sorption-desorption test in vivo with and without sunscreens. Finally, we studied the effect of constant water exposure combined with a known irritant, sodium lauryl sulphate (SLS), in a randomized clinical trial. We found that application of sunscreen formulations help mitigate water-induced barrier disruption by repelling water at skin surface. Pre-treatment of sunscreen also statistically decreased the irritation in an acute patch test model. Hydrophobic sunscreen formulations can help protect skin from extended water exposure by serving as additional water barriers. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  6. Gaps between Knowing and Doing: Understanding and Assessing the Barriers to Optimal Health Care

    ERIC Educational Resources Information Center

    Cochrane, Lorna J.; Olson, Curtis A.; Murray, Suzanne; Dupuis, Martin; Tooman, Tricia; Hayes, Sean

    2007-01-01

    Introduction: A significant gap exists between science and clinical practice guidelines, on the one hand, and actual clinical practice, on the other. An in-depth understanding of the barriers and incentives contributing to the gap can lead to interventions that effect change toward optimal practice and thus to better care. Methods: A systematic…

  7. Gaps between Knowing and Doing: Understanding and Assessing the Barriers to Optimal Health Care

    ERIC Educational Resources Information Center

    Cochrane, Lorna J.; Olson, Curtis A.; Murray, Suzanne; Dupuis, Martin; Tooman, Tricia; Hayes, Sean

    2007-01-01

    Introduction: A significant gap exists between science and clinical practice guidelines, on the one hand, and actual clinical practice, on the other. An in-depth understanding of the barriers and incentives contributing to the gap can lead to interventions that effect change toward optimal practice and thus to better care. Methods: A systematic…

  8. An Improved Database System for Program Assessment

    ERIC Educational Resources Information Center

    Haga, Wayne; Morris, Gerard; Morrell, Joseph S.

    2011-01-01

    This research paper presents a database management system for tracking course assessment data and reporting related outcomes for program assessment. It improves on a database system previously presented by the authors and in use for two years. The database system presented is specific to assessment for ABET (Accreditation Board for Engineering and…

  9. Supports and barriers to implementation of routine clinical assessment for children with cerebral palsy: A mixed-methods study.

    PubMed

    Kerr, Claire; Shields, Nora; Quarmby, Lyndsay; Roberts, Karen; Imms, Christine

    2016-12-15

    The purpose of this study is to investigate supports and barriers to evidence-based routine clinical assessment of children with cerebral palsy. This mixed methods study included physiotherapists, occupational therapists and speech pathologists providing services to children with cerebral palsy (3-18 years) within five organizations across Australia. Four organizations initiated standardized routine clinical data collection (Commencing organizations), and one had previously mandated routine assessment (Comparison organization). Participants completed the Supports and Barriers Questionnaire (n = 227) and participated in focus groups (n = 8 groups, 37 participants). Quantitative data were summarized descriptively, qualitative data were analyzed thematically and comparisons between organizations assessed. Organizational structures, resources, therapists within organizations, assessment tools, and children and families were, on average, viewed as supportive of routine clinical assessment. There were no differences between the Comparison and Commencing organizations except 'therapists within the organization' were viewed as more supportive by the Commencing organizations (p = 0.037). Five themes were derived from qualitative analyzes: motivation to adopt routine clinical assessment; acquiring and utilizing expertise; ensuring effective ongoing communication; availability and distribution of resources; and therapist perceptions of child and family wishes. Organizations experience challenges to effective and sustained implementation of routine clinical assessment. Adequate resourcing and positive, clear communication were perceived as critical for success. Implications for Rehabilitation The value of routine clinical assessment of children with cerebral palsy is undisputed. Tailored solutions to organization-specific challenges are required when implementing routine clinical assessment for children with cerebral palsy. Positive, clear communication of

  10. Sensitive Skin: Assessment of the Skin Barrier Using Confocal Raman Microspectroscopy.

    PubMed

    Richters, Renée J H; Falcone, Denise; Uzunbajakava, Natallia E; Varghese, Babu; Caspers, Peter J; Puppels, Gerwin J; van Erp, Piet E J; van de Kerkhof, Peter C M

    2017-01-01

    Sensitive skin (SS), a frequently reported condition in the Western world, has been suggested to be underlined by an impaired skin barrier. The aim of this study was to investigate the skin barrier molecular composition in SS subjects using confocal Raman microspectroscopy (CRS), and to compare it with that of non-SS (NSS) individuals as well as atopic dermatitis (AD) and allergic rhinoconjunctivitis (AR) subjects, who frequently report SS. Subjects with SS (n = 29), NSS (n = 30), AD (n = 11), and AR (n = 27) were included. Stratum corneum (SC) thickness, water, ceramides/fatty acids, and natural moisturizing factor (NMF) were measured by CRS along with transepidermal water loss and capacitance on the ventral forearm, thenar, and cheek. Sebum levels were additionally measured on the forearm and cheek. No differences between SS and NSS subjects were found regarding SC thickness, water, and NMF content, yet a trend towards lower ceramides/fatty acids was observed in the cheek. Compared to AD subjects, the SS group showed higher ceramides/fatty acid content in the forearm, whereas no differences emerged with AR. The correlation of macroscopic biophysical techniques and CRS was weak, yet CRS confirmed the well-known lower content of NMF and water, and thinner SC in subjects with filaggrin mutations. The skin barrier in SS is not impaired in terms of SC thickness, water, NMF, and ceramides/fatty acid content. The failure of biophysical techniques to follow alterations in the molecular composition of the skin barrier revealed by CRS emphasizes a strong need in sensitive and specific tools for in vivo skin barrier analysis. © 2017 S. Karger AG, Basel.

  11. Sensitive Skin: Assessment of the Skin Barrier Using Confocal Raman Microspectroscopy

    PubMed Central

    Richters, Renée J.H.; Falcone, Denise; Uzunbajakava, Natallia E.; Varghese, Babu; Caspers, Peter J.; Puppels, Gerwin J.; van Erp, Piet E.J.; van de Kerkhof, Peter C.M.

    2017-01-01

    Background/Aims Sensitive skin (SS), a frequently reported condition in the Western world, has been suggested to be underlined by an impaired skin barrier. The aim of this study was to investigate the skin barrier molecular composition in SS subjects using confocal Raman microspectroscopy (CRS), and to compare it with that of non-SS (NSS) individuals as well as atopic dermatitis (AD) and allergic rhinoconjunctivitis (AR) subjects, who frequently report SS. Methods Subjects with SS (n = 29), NSS (n = 30), AD (n = 11), and AR (n = 27) were included. Stratum corneum (SC) thickness, water, ceramides/fatty acids, and natural moisturizing factor (NMF) were measured by CRS along with transepidermal water loss and capacitance on the ventral forearm, thenar, and cheek. Sebum levels were additionally measured on the forearm and cheek. Results No differences between SS and NSS subjects were found regarding SC thickness, water, and NMF content, yet a trend towards lower ceramides/fatty acids was observed in the cheek. Compared to AD subjects, the SS group showed higher ceramides/fatty acid content in the forearm, whereas no differences emerged with AR. The correlation of macroscopic biophysical techniques and CRS was weak, yet CRS confirmed the well-known lower content of NMF and water, and thinner SC in subjects with filaggrin mutations. Conclusion The skin barrier in SS is not impaired in terms of SC thickness, water, NMF, and ceramides/fatty acid content. The failure of biophysical techniques to follow alterations in the molecular composition of the skin barrier revealed by CRS emphasizes a strong need in sensitive and specific tools for in vivo skin barrier analysis. PMID:28122376

  12. Energetic and structural consequences of desolvation/solvation barriers to protein folding/unfolding assessed from experimental unfolding rates.

    PubMed

    Rodriguez-Larrea, David; Ibarra-Molero, Beatriz; Sanchez-Ruiz, Jose M

    2006-09-01

    Theoretical work has suggested the existence of solvation/desolvation barriers in protein folding/unfolding processes. We propose that the energetic and structural consequences of such barriers for the folding transition state can be assessed from experimental unfolding rates using well-established structure-energetics relationships. For a set of proteins of size within the 60-130 number-of-residues range, we find energetic effects associated to solvation/desolvation on the order of 10(2) kJ/mol. This supports that the folding transition states may be characterized by large networks of water-unsatisfied, broken internal contacts. In terms of buried surface, we estimate the typical network size to be on the order of several thousands of A2, or approximately 50% of the total change in accessible surface area upon unfolding. The analyses reported here thus suggest a clear structural picture for the different energetic balance of native and folding transition states.

  13. Prevention of secondary conditions in fetal alcohol spectrum disorders: identification of systems-level barriers.

    PubMed

    Petrenko, Christie L M; Tahir, Naira; Mahoney, Erin C; Chin, Nancy P

    2014-08-01

    Fetal alcohol spectrum disorders (FASD) impact 2-5% of the US population and are associated with life-long cognitive and behavioral impairments. Individuals with FASD have high rates of secondary conditions, including mental health problems, school disruptions, and trouble with the law. This study focuses on systems-level barriers that contribute to secondary conditions and interfere with prevention and treatment. Using a phenomenological methodology, semi-structured interviews and focus groups were conducted with parents of children with FASD and service providers. Data were analyzed using a framework approach. Participants emphasized the pervasive lack of knowledge of FASD throughout multiple systems. This lack of knowledge contributes to multi-system barriers including delayed diagnosis, unavailability of services, and difficulty qualifying for, implementing, and maintaining services. FASD is a major public health problem. Broad system changes using a public health approach are needed to increase awareness and understanding of FASD, improve access to diagnostic and therapeutic services, and create responsive institutional policies to prevent secondary conditions. These changes are essential to improve outcomes for individuals with FASD and their families and facilitate dissemination of empirically supported interventions.

  14. Prevention of Secondary Conditions in Fetal Alcohol Spectrum Disorders: Identification of Systems-Level Barriers

    PubMed Central

    Petrenko, Christie L. M.; Tahir, Naira; Mahoney, Erin C.; Chin, Nancy P.

    2013-01-01

    Objective Fetal alcohol spectrum disorders (FASD) impact 2 to 5 percent of the U.S. population and are associated with life-long cognitive and behavioral impairments. Individuals with FASD have high rates of secondary conditions, including mental health problems, school disruptions, and trouble with the law. This study focuses on systems-level barriers that contribute to secondary conditions and interfere with prevention and treatment. Methods Using a phenomenological methodology, semi-structured interviews and focus groups were conducted with parents of children with FASD and service providers. Data were analyzed using a framework approach. Results Participants emphasized the pervasive lack of knowledge of FASD throughout multiple systems. This lack of knowledge contributes to multi-system barriers including delayed diagnosis, unavailability of services, and difficulty qualifying for, implementing, and maintaining services. Conclusions FASD is a major public health problem. Broad system changes using a public health approach are needed to increase awareness and understanding of FASD, improve access to diagnostic and therapeutic services, and create responsive institutional policies to prevent secondary conditions. These changes are essential to improve outcomes for individuals with FASD and their families and facilitate dissemination of empirically supported interventions. PMID:24178158

  15. Understanding the modifiable health systems barriers to hypertension management in Malaysia: a multi-method health systems appraisal approach.

    PubMed

    Risso-Gill, Isabelle; Balabanova, Dina; Majid, Fadhlina; Ng, Kien Keat; Yusoff, Khalid; Mustapha, Feisul; Kuhlbrandt, Charlotte; Nieuwlaat, Robby; Schwalm, J-D; McCready, Tara; Teo, Koon K; Yusuf, Salim; McKee, Martin

    2015-07-03

    The growing burden of non-communicable diseases in middle-income countries demands models of care that are appropriate to local contexts and acceptable to patients in order to be effective. We describe a multi-method health system appraisal to inform the design of an intervention that will be used in a cluster randomized controlled trial to improve hypertension control in Malaysia. A health systems appraisal was undertaken in the capital, Kuala Lumpur, and poorer-resourced rural sites in Peninsular Malaysia and Sabah. Building on two systematic reviews of barriers to hypertension control, a conceptual framework was developed that guided analysis of survey data, documentary review and semi-structured interviews with key informants, health professionals and patients. The analysis followed the patients as they move through the health system, exploring the main modifiable system-level barriers to effective hypertension management, and seeking to explain obstacles to improved access and health outcomes. The study highlighted the need for the proposed intervention to take account of how Malaysian patients seek treatment in both the public and private sectors, and from western and various traditional practitioners, with many patients choosing to seek care across different services. Patients typically choose private care if they can afford to, while others attend heavily subsidised public clinics. Public hypertension clinics are often overwhelmed by numbers of patients attending, so health workers have little time to engage effectively with patients. Treatment adherence is poor, with a widespread belief, stemming from concepts of traditional medicine, that hypertension is a transient disturbance rather than a permanent asymptomatic condition. Drug supplies can be erratic in rural areas. Hypertension awareness and education material are limited, and what exist are poorly developed and ineffective. Despite having a relatively well funded health system offering good access to

  16. Blood-brain barrier-on-a-chip: Microphysiological systems that capture the complexity of the blood-central nervous system interface.

    PubMed

    Phan, Duc Tt; Bender, R Hugh F; Andrejecsk, Jillian W; Sobrino, Agua; Hachey, Stephanie J; George, Steven C; Hughes, Christopher Cw

    2017-01-01

    The blood-brain barrier is a dynamic and highly organized structure that strictly regulates the molecules allowed to cross the brain vasculature into the central nervous system. The blood-brain barrier pathology has been associated with a number of central nervous system diseases, including vascular malformations, stroke/vascular dementia, Alzheimer's disease, multiple sclerosis, and various neurological tumors including glioblastoma multiforme. There is a compelling need for representative models of this critical interface. Current research relies heavily on animal models (mostly mice) or on two-dimensional (2D) in vitro models, neither of which fully capture the complexities of the human blood-brain barrier. Physiological differences between humans and mice make translation to the clinic problematic, while monolayer cultures cannot capture the inherently three-dimensional (3D) nature of the blood-brain barrier, which includes close association of the abluminal side of the endothelium with astrocyte foot-processes and pericytes. Here we discuss the central nervous system diseases associated with blood-brain barrier pathology, recent advances in the development of novel 3D blood-brain barrier -on-a-chip systems that better mimic the physiological complexity and structure of human blood-brain barrier, and provide an outlook on how these blood-brain barrier-on-a-chip systems can be used for central nervous system disease modeling.

  17. Evolution of fusion hindrance for asymmetric systems at deep sub-barrier energies

    NASA Astrophysics Data System (ADS)

    Shrivastava, A.; Mahata, K.; Pandit, S. K.; Nanal, V.; Ichikawa, T.; Hagino, K.; Navin, A.; Palshetkar, C. S.; Parkar, V. V.; Ramachandran, K.; Rout, P. C.; Kumar, Abhinav; Chatterjee, A.; Kailas, S.

    2016-04-01

    Measurements of fusion cross-sections of 7Li and 12C with 198Pt at deep sub-barrier energies are reported to unravel the role of the entrance channel in the occurrence of fusion hindrance. The onset of fusion hindrance has been clearly observed in 12C +198Pt system but not in 7Li +198Pt system, within the measured energy range. Emergence of the hindrance, moving from lighter (6,7Li) to heavier (12C, 16O) projectiles is explained employing a model that considers a gradual transition from a sudden to adiabatic regime at low energies. The model calculation reveals a weak effect of the damping of coupling to collective motion for the present systems as compared to that obtained for systems with heavier projectiles.

  18. Identifying barriers and facilitators to ambulance service assessment and treatment of acute asthma: a focus group study

    PubMed Central

    2014-01-01

    Background Acute asthma is a common reason for patients to seek care from ambulance services. Although better care of acute asthma can prevent avoidable morbidity and deaths, there has been little research into ambulance clinicians’ adherence to national guidelines for asthma assessment and management and how this might be improved. Our research aim was to explore paramedics’ attitudes, perceptions and beliefs about prehospital management of asthma, to identify barriers and facilitators to guideline adherence. Methods We conducted three focus group interviews of paramedics in a regional UK ambulance trust. We used framework analysis supported by NVivo 8 to code and analyse the data. Results Seventeen participants, including paramedics, advanced paramedics or paramedic operational managers at three geographical sites, contributed to the interviews. Analysis led to five themes: (1) guidelines should be made more relevant to ambulance service care; (2) there were barriers to assessment; (3) the approach needed to address conflicts between clinicians’ and patients’ expectations; (4) the complexity of ambulance service processes and equipment needed to be taken into account; (5) and finally there were opportunities for improved prehospital education, information, communication, support and care pathways for asthma. Conclusions This qualitative study provides insight into paramedics’ perceptions of the assessment and management of asthma, including why paramedics may not always follow guidelines for assessment or management of asthma. These findings provide opportunities to strengthen clinical support, patient communication, information transfer between professionals and pathways for prehospital care of patients with asthma. PMID:25086749

  19. Two-layer thermal-barrier systems for Ni-Al-Mo alloy and effects of alloy thermal expansion on system life

    NASA Technical Reports Server (NTRS)

    Stecura, S.

    1982-01-01

    Cyclic furnace and cyclic natural gas-oxygen torch rig tests were conducted to (1) identify a thermal-barrier system for a nickel-aluminum-molybdenum alloy, (2) study the oxidation of the bond coating, and (3) study the effect of the substrate coefficient of thermal expansion on thermal barrier system life. It is found that the latter is affected by the composition of the bond coating, yttria concentration in zirconia, and the coefficient of thermal expansion of the substrate material. In addition, small compositional changes in the bond and thermal barrier coatings have greater effect on thermal barrier system life than the 40% increase in the coefficient of thermal expansion of the substrate material. No simple relation exists between the weight gain caused by bond-coating oxidation with increasing yttria concentration in zirconia and increasing bond coating thickness on the one hand, and thermal barrier system life on the other.

  20. OVERCOMING THE METER BARRIER AND THE FORMATION OF SYSTEMS WITH TIGHTLY PACKED INNER PLANETS (STIPs)

    SciTech Connect

    Boley, A. C.; Morris, M. A.; Ford, E. B.

    2014-09-10

    We present a solution to the long outstanding meter barrier problem in planet formation theory. As solids spiral inward due to aerodynamic drag, they will enter disk regions that are characterized by high temperatures, densities, and pressures. High partial pressures of rock vapor can suppress solid evaporation, and promote collisions between partially molten solids, allowing rapid growth. This process should be ubiquitous in planet-forming disks, which may be evidenced by the abundant class of Systems with Tightly packed Inner Planets discovered by the NASA Kepler Mission.

  1. Interactions between surface discharges induced by volume discharges in a dielectric barrier discharge system

    SciTech Connect

    Gao, Yenan; Dong, Lifang Zhao, Longhu; Wang, Yongjie; Pan, Yuyang; Li, Ben

    2014-10-15

    The interaction between micro-discharges involved in surface discharges (SDs) is studied in dielectric barrier discharge system. Instantaneous images taken by high speed cameras show that the SDs are induced by volume discharges (VDs). They cannot cross the midperpendicular of two neighbouring volume charges at low voltage while they stretch along it at high voltage, indicating that there is interaction between SDs. The differences of plasma parameters between SD and VD are studied by optical emission spectroscopy. The simulation of the electric fields of the wall charges accumulated by VD further confirms the existence of the interaction.

  2. Role of histaminergic system in blood-brain barrier dysfunction associated with neurological disorders.

    PubMed

    Bañuelos-Cabrera, Ivette; Valle-Dorado, María Guadalupe; Aldana, Blanca Irene; Orozco-Suárez, Sandra Adela; Rocha, Luisa

    2014-11-01

    Blood-brain barrier (BBB) disruption has been associated with several acute and chronic brain disorders such as Alzheimer's disease, Parkinson's disease and epilepsy. This represents a critical situation because damaged integrity of the BBB is related to the influx of immune mediators, plasma proteins and other outside elements from blood to the central nervous system (CNS) that may trigger a cascade of events that leads to neuroinflammation. In this review, evidence that mast cells and the release of factors such as histamine play an important role in the neuroinflammatory process associated with brain disorders such as Alzheimer's disease, Parkinson's disease and epilepsy is presented.

  3. Role of barrier layer on dielectric function of graphene double layer system at finite temperature

    NASA Astrophysics Data System (ADS)

    Patel, Digish K.; Ambavale, Sagar K.; Prajapati, Ketan; Sharma, A. C.

    2016-05-01

    We have theoretically investigated the static dielectric function of graphene double layer system (GDLS) at finite temperatures within the random phase approximation. GDLS has been suspended on a substrate and barrier layer of three different materials; h-BN, Al2O3 and HfO2 has been introduced between two graphene sheets of GDLS. We have reported dependence of the overall dielectric function of GDLS on interlayer distance and the effect of the dielectric environment at finite temperatures. Results show close relation between changing environment and behavior of dielectric constant of GDLS.

  4. Burden of Circulatory System Diseases and Ignored Barriers of Knowledge Translation

    PubMed Central

    Ghafouri, Hamed-Basir; Saravani, Shahzad; Shokraneh, Farhad

    2012-01-01

    Circulatory system disease raise third highest disability-adjusted life years among Iranians and ischemic cardiac diseases are main causes for such burden. Despite available evidences on risk factors of the disease, no effective intervention was implemented to control and prevent the disease. This paper non-systematically reviews available literature on the problem, solutions, and barriers of implementation of knowledge translation in Iran. It seems that there are ignored factors such as cultural and motivational issues in knowledge translation interventions but there are hopes for implementation of started projects and preparation of students as next generation of knowledge transferors. PMID:24250994

  5. Nanofiber-based filters as novel barrier systems for nanomaterial exposure scenarios

    NASA Astrophysics Data System (ADS)

    Faccini, M.; Amantia, D.; Vázquez-Campos, S.; Vaquero, C.; López de Ipiña, J. M.; Aubouy, L.

    2011-07-01

    In this article our latest advances in the development of efficient barrier systems against micro- and nano-particulate materials are presented. Nanofibrous polyamide 6 (PA6) mats were fabricated by electrospinning onto a nonwoven viscose substrate. The influence of electrospinning parameters including solution concentration, viscosity, and conductivity, were studied for the production of nonwovens with different fiber size distribution ranging from 74 to 261 nm in diameters. Moreover, the formation of nanowebs (30-40 nm) which are widely distributed among fibers was observed. By varying several process parameters, membranes with different thickness of the nanofiber layer and therefore air permeability and nanoparticle filtration efficiency were obtained.

  6. Entangled trajectory molecular dynamics in multidimensional systems: two-dimensional quantum tunneling through the Eckart barrier.

    PubMed

    Wang, Lifei; Martens, Craig C; Zheng, Yujun

    2012-07-21

    In this paper, we extend the entangled trajectory molecular dynamics (ETMD) method to multidimensional systems. The integrodifferential form of the evolution equation for the Wigner function is employed, allowing general potentials not represented as a polynomial to be treated. As the example, the method is applied to a two-dimensional model of scattering from an Eckart barrier. The results of ETMD are in good agreement with quantum hydrodynamics and exact quantum simulations. By comparing the quantum and classical trajectory in phase space, the quantum tunneling phenomenon is interpreted vividly.

  7. Direct Observation of an Exhumed Earthquake Barrier Preserved in a Pseudotachylyte System

    NASA Astrophysics Data System (ADS)

    Allen, J. L.

    2011-12-01

    The barrier model of earthquake rupture propagation (Das and Aki, 1977) accounts for the retardation or stopping of ruptures as they propagate into a fault segment that resists breaking relative to other segments of the same fault. The barrier model is founded on the premise that zones of relatively high resistance S affect ruptures; it is expressed as the non-dimensional ratio S = (τy - τi)/( τi - τf), where τi is the initial pre-rupture stress, τy is the yield stress, and τf is the dynamic shear resistance (shear stress). Despite models that seek to explain source complexity through fault heterogeneity, the existence of barriers as a physical geologic phenomenon in the subsurface is only known through indirect observations, such as seismogram records and rupture traces at Earth's surface, or by inference from exhumed faults that may not have been seismogenic. In this study, it is proposed that the distribution of pseudotachylyte-bearing fault zones in a segment of the Homestake shear zone (HSZ) provides the first unequivocal verification of the existence of an earthquake barrier at seismogenic depths. The HSZ is preserved as a 25-km-long, 2.5-km-wide transpressional fault system consisting of pseudotachylyte, mylonite, and mylonitic pseudotachylyte exhumed from mid-crustal depths in Proterozoic amphibolite-facies gneisses and migmatites in the Colorado Rockies. Most pseudotachylyte zones in the HSZ are concordant with a subvertical gneissic foliation; however, within one 500 m segment, pseudotachylyte zones discordantly crosscut the foliation. In order to compare rupture behavior within this discordant domain to ruptures within concordant domains, pseudotachylyte thickness was quantified in 9 cross-strike transects in both domains. In addition, melt volume, damage-zone asymmetry, and displacement was quantified and compared in the concordant and discordant domains in 10 individual fault veins and associated melt-filled damage zones, each of which

  8. Barrier-bar system in Cerro Negro, orinoco Petroliferous belt, Venezuela, and its implication in oil exploration and exploitation

    SciTech Connect

    Rodriguez, A.

    1985-02-01

    Barrier bars are important stratigraphic traps for oil and/or gas because of deposition in relatively shallow and often agitated waters, which allow barriers to develop excellent primary porosity and high permeability. Barrier bars can be developed as component facies of other depositional systems such as deltas or as independent interdeltaic systems associated with a major delta. In each case, different facies relationships such as distributary channel, mouth-bar, distal-bar, and prodelta facies would be present in a deltaic setting. Barrier bars, lagoons, washover-fans, and nonmarine facies could occur in an independent interdeltaic system. Different sand geometry patterns and reservoir characteristics are found in each system. In the Cerro Negro area, the sedimentary parameters are composite sand bodies, Ophiomorpha-type burrows, bioturbation structures, shell fragments, and an interfingering of brackish and shallow-marine fauna. Seven continuously cored wells and more than 100 geophysical well logs were used to determine lithofacies associations and to construct computer-drawn maps. These data were used to propose and support an independent interdeltaic barrier-bar system as the depositional model for the Cerro Negro area. Barriers were found to be mainly parallel to a paleoshoreline, and to have porosity values greater than 20% and permeability values greater than 500 md. It is interesting to note that different rates of heavy oil production can be related to the facies present.

  9. Implications of non-equilibrium transport in heterogeneous reactive barrier systems: evidence from laboratory denitrification experiments.

    PubMed

    Herbert, Roger B

    2011-04-01

    Organic substrates in reactive barrier systems are often heterogeneous material mixtures with relatively large contrasts in hydraulic conductivity and porosity over short distances. These short-range variations in material properties imply that preferential flow paths and diffusion between regions of higher and lower hydraulic conductivity may be important for treatment efficiency. This paper presents the results of a laboratory column experiment where denitrification is investigated using a heterogeneous reactive substrate (sawdust mixed with sewage sludge). Displacement experiments with a non-reactive solute at three different flow rates are used to estimate transport parameters using a dual porosity non-equilibrium model. Parameter estimation from breakthrough curves produced relatively consistent values for the fraction of the porosity consisting of mobile water (β) and the mass transfer coefficient (α), with average values of 0.27 and 0.42 d(-1), respectively. The column system removes >95% of the influent nitrate at low and medium flow, but only 50-75% of the influent nitrate at high flow, suggesting that denitrification kinetics and diffusive mass transfer rates are limiting the degree of treatment at lower hydraulic residence times. Reactive barrier systems containing dual porosity media must therefore consider mass transfer times in their design; this is often most easily accommodated by adjusting flowpath length. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. Implications of non-equilibrium transport in heterogeneous reactive barrier systems: Evidence from laboratory denitrification experiments

    NASA Astrophysics Data System (ADS)

    Herbert, Roger B., Jr.

    2011-04-01

    Organic substrates in reactive barrier systems are often heterogeneous material mixtures with relatively large contrasts in hydraulic conductivity and porosity over short distances. These short-range variations in material properties imply that preferential flow paths and diffusion between regions of higher and lower hydraulic conductivity may be important for treatment efficiency. This paper presents the results of a laboratory column experiment where denitrification is investigated using a heterogeneous reactive substrate (sawdust mixed with sewage sludge). Displacement experiments with a non-reactive solute at three different flow rates are used to estimate transport parameters using a dual porosity non-equilibrium model. Parameter estimation from breakthrough curves produced relatively consistent values for the fraction of the porosity consisting of mobile water (β) and the mass transfer coefficient (α), with average values of 0.27 and 0.42 d - 1 , respectively. The column system removes > 95% of the influent nitrate at low and medium flow, but only 50-75% of the influent nitrate at high flow, suggesting that denitrification kinetics and diffusive mass transfer rates are limiting the degree of treatment at lower hydraulic residence times. Reactive barrier systems containing dual porosity media must therefore consider mass transfer times in their design; this is often most easily accommodated by adjusting flowpath length.

  11. Assessment of common interventions and perceived barriers to pressure ulcer prevention in southwest Nigeria.

    PubMed

    Ilesanmi, Rose Ekama; Olabisi, Prisca

    2014-01-01

    We examined the interventions used by nurses to prevent pressure ulcers in 3 hospitals in south west Nigeria and perceived barriers to effective nursing pressure ulcer prevention interventions. One hundred ninety-three nurses were purposively selected from neurological, orthopedic, intensive care, and accident and emergency units of participating hospitals. Study sites were 3 teaching hospitals in south west Nigeria (Lagos State University Teaching Hospital, Lagos; University College Hospital, Ibadan; and Obafemi Awolowo Teaching Hospital Ile-Ife). Data were collected via a structured questionnaire designed for this study. It included 3 sections: demographic information, practices used for pressure ulcer prevention, and perceived barriers to prevention. Sections of the questionnaire that queried interventions and perceived barriers to pressure ulcer prevention were evaluated for face and content validity. Reliability was evaluated via internal consistency; the split half reliability was 0.82. Similar practices regarding pressure ulcer prevention were found across the 3 hospitals. The most commonly used intervention was patient repositioning every 2 hours; the least used intervention was completion of a validated pressure ulcer risk scale. Nurses described using interventions that have not proved effective for pressure ulcer prevention such as massaging bony prominences and application of talcum powder. Nurses identified 2 principal factors that act as barriers to successful prevention of pressure ulcers: inadequate manpower and inadequate supply of linens on the wards. Nurses use a combination of evidence-based interventions, along with interventions that have not proved effective for pressure ulcer prevention. We recommend development of national standards for pressure ulcer prevention in Nigeria that are based on current best evidence and consistent with current international guidelines.

  12. PATTERNS OF PHYSICAL ACTIVITY AMONG AMERICAN INDIAN CHILDREN: AN ASSESSMENT OF BARRIERS AND SUPPORT

    PubMed Central

    Thompson, Janice L.; Davis, Sally M.; Gittelsohn, Joel; Going, Scott; Becenti, Alberta; Metcalfe, Lauve; Stone, Elaine; Harnack, Lisa; Ring, Kim

    2016-01-01

    Estimates indicate that 10% to 50% of American Indian and non-Indian children in the U.S. are obese, defined as a body mass index ≥ 95th percentile of the NHANES II reference data. Pathways is a two-phase, multi-site study to develop and test a school-based obesity prevention program in American Indian schoolchildren in grades three through five. During Phase I feasibility prior to initiation of the Pathways trial, data were collected related to physical activity patterns, and the supports of, and barriers to, physical activity. Nine schools from communities representing six different tribal groups participated in this study. Multiple measures were used for data collection including direct observation, paired child interviews, and in-depth interviews and focus groups with adults. Students completed the self-administered Knowledge, Attitudes, and Behaviors (KAB) survey, and a Physical Activity Questionnaire (PAQ). Barriers to physical activity at schools included a lack of facilities, equipment, and trained staff persons for PE. Adults were not consistently active with their children, but they were highly supportive of their children’s activity level. Children reported a strong enjoyment of physical activity and strong peer support to be physically active. Weather conditions, safety concerns, and homework/chores were common barriers to physical activity reported by children and adult caregivers. The information was used to design culturally and age-appropriate, practical interventions including the five physical activity programs for schoolchildren in the Pathways study. PMID:11759094

  13. Flow barrier system for long-term high-level-waste isolation: Experimental results

    SciTech Connect

    Conca, J.L.; Apted, M.J.; Zhou, W.; Arthur, R.C.; Kessler, J.H.

    1998-10-01

    A flow barrier system (FBS) that includes a Richards barrier acts in an unsaturated hydrogeologic system to prevent the advective flow of water down through the barrier. Thus, an FBS placed above any solid waste material buried in the unsaturated zone could greatly aid in isolating the waste by keeping the waste away from flowing water. The FBS, consisting of a layer of highly conductive, fine-grained material overlying a sloped gravel layer, is proposed to isolate high-level radioactive waste (HLW) at a candidate disposal facility located in the unsaturated zone at Yucca Mountain in Nevada. A series of laboratory experiments were conducted to (a) assure that the FBS of a specific design can divert the anticipated maximum advective flow (under ideal conditions as well as for the case of a disturbed interface between the two layers caused by, for example, improper initial emplacement or faulting due to seismic activity), (b) investigate water inhibition into the gravel, and (c) measure the diffusion coefficient of the tuff gravel under partially saturated conditions. The main results show that (a) the FBS used in the study can divert point-source flow rates as high as 2.6 {times} 10{sup 5} {ell}/yr; (b) this FBS will continue performing with offsets of the interface as great as 50 cm or more; (c) after 12 months of testing, moisture penetrates the gravel only several grain diameters; and (d) the gravel effective diffusion coefficient is <10{sup {minus}11} cm{sup 2}/s under such low partial saturations. These results indicate that a properly designed FBS can be successful at isolating the HLW under the anticipated range of environmental conditions that exist both now and in the future at Yucca Mountain.

  14. Systems and methods for measuring a parameter of a landfill including a barrier cap and wireless sensor systems and methods

    DOEpatents

    Kunerth, Dennis C.; Svoboda, John M.; Johnson, James T.

    2007-03-06

    A method of measuring a parameter of a landfill including a cap, without passing wires through the cap, includes burying a sensor apparatus in the landfill prior to closing the landfill with the cap; providing a reader capable of communicating with the sensor apparatus via radio frequency (RF); placing an antenna above the barrier, spaced apart from the sensor apparatus; coupling the antenna to the reader either before or after placing the antenna above the barrier; providing power to the sensor apparatus, via the antenna, by generating a field using the reader; accumulating and storing power in the sensor apparatus; sensing a parameter of the landfill using the sensor apparatus while using power; and transmitting the sensed parameter to the reader via a wireless response signal. A system for measuring a parameter of a landfill is also provided.

  15. Sub-barrier fusion of {sup 36}S + {sup 64}Ni and other medium-light systems

    SciTech Connect

    Montagnoli, G.; Scarlassara, F.; Stefanini, A. M.; Corradi, L.; Fioretto, E.; Silvestri, R.; Courtin, S.; Haas, F.; Lebhertz, D.; Szilner, S.

    2010-12-15

    Sub-barrier fusion cross sections of {sup 36}S + {sup 64}Ni have been measured down to {approx_equal}3 {mu}b. The logarithmic slope of the fusion excitation function has a steep rise in the barrier region with decreasing energy and saturates at lower energies. The data can be reproduced within the coupled-channels model using a Woods-Saxon potential with a large diffuseness. The slope saturation is analogous to what has been observed for {sup 36}S, {sup 48}Ca + {sup 48}Ca, while for heavier systems the slope increases steadily below the barrier.

  16. Optimization of the NiCrAl-Y/ZrO-Y2O3 thermal barrier system

    NASA Technical Reports Server (NTRS)

    Stecura, S.

    1985-01-01

    The effects of bond and thermal barrier coating compositions, thicknesses, and densities on air plasma spray deposited Ni-Cr-Al-Y/ZrO2-Y2O3 life were evaluated in cyclic furnace oxidation tests at temperatures from 1110 to 1220 C. An empirical relation was developed to give life as a function of the above parameters. The thermal barrier system tested which had the longest life consisted of Ni-35.0 wt% Cr-5.9 wt% Al-0.95 wt% Y bond coating and ZrO2-6.1 wt% Y2O3 thermal barrier coating.

  17. Drug transport into the central nervous system: using newer findings about the blood-brain barriers.

    PubMed

    Banks, William A

    2012-06-01

    The blood-brain barriers (BBBs) represent one of the biggest challenges for the effective delivery of drugs today. Discoveries made in the last 30 years offer new strategies for central nervous system (CNS) drug development, but have yet to be fully incorporated into the field. Here, we examine seven recently discovered aspects of the BBB and how they have been or could be developed for drug delivery. These areas are brain-to-blood (efflux) transporters, immune cell trafficking into the brain under physiologic conditions, mechanisms by which antibodies can access the CNS, Trojan horse delivery systems, blood-to-brain transport systems for biologicals, lectin interactions and ligand modifications that enhance BBB penetration, and secretory capacities of cells comprising the BBBs.

  18. A qualitative assessment of barriers to antiretroviral therapy adherence among adolescents in western Kenya.

    PubMed

    Kunapareddy, Catherine June; Nyandiko, Winstone; Inui, Thomas; Ayaya, Samwel; Marrero, David G; Vreeman, Rachel

    2014-10-01

    Antiretroviral therapy (ART) requires nearly perfect adherence to be effective. This study aims to identify key factors identified by HIV-infected adolescents on ART as contributing to medication adherence in western Kenya. Using a qualitative study design, three adolescent focus groups discussions were conducted at an urban and rural clinic site in western Kenya. The study population included HIV-infected adolescents receiving ART through the USAID-AMPATH HIV care system. A trained facilitator conducted groups in Kiswahili using a semi-structured interview guide probing multiple aspects of experience of taking medicines. Transcribed focus group dialogues were analyzed using constant comparison, progressive coding, and triangulation. The adolescents described a context of negative societal beliefs about HIV, necessitating a lifestyle of secrecy and minimizing the information shared about HIV or ART. Assessing and addressing adolescents' fears and behaviors regarding medication secrecy and disclosure may enable more accurate monitoring of adherence and development of intervention strategies.

  19. A qualitative assessment of barriers to antiretroviral therapy adherence among adolescents in western Kenya

    PubMed Central

    Kunapareddy, Catherine June; Nyandiko, Winstone; Inui, Thomas; Ayaya, Samwel; Marrero, David G.; Vreeman, Rachel

    2015-01-01

    Antiretroviral therapy (ART) requires nearly perfect adherence to be effective. This study aims to identify key factors identified by HIV-infected adolescents on ART as contributing to medication adherence in western Kenya. Using a qualitative study design, three adolescent focus groups discussions were conducted at an urban and rural clinic site in western Kenya. The study population included HIV-infected adolescents receiving ART through the USAID-AMPATH HIV care system. A trained facilitator conducted groups in Kiswahili using a semi-structured interview guide probing multiple aspects of experience of taking medicines. Transcribed focus group dialogues were analyzed using constant comparison, progressive coding, and triangulation. The adolescents described a context of negative societal beliefs about HIV, necessitating a lifestyle of secrecy and minimizing the information shared about HIV or ART. Assessing and addressing adolescents’ fears and behaviors regarding medication secrecy and disclosure may enable more accurate monitoring of adherence and development of intervention strategies. PMID:28367106

  20. Thermal Gradient Cyclic Behavior of a Thermal/Environmental Barrier Coating System on SiC/SiC Ceramic Matrix Composites

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Lee, Kang N.; Miller, Robert A.

    2002-01-01

    Thermal barrier and environmental barrier coatings (TBCs and EBCs) will play a crucial role in future advanced gas turbine engines because of their ability to significantly extend the temperature capability of the ceramic matrix composite (CMC) engine components in harsh combustion environments. In order to develop high performance, robust coating systems for effective thermal and environmental protection of the engine components, appropriate test approaches for evaluating the critical coating properties must be established. In this paper, a laser high-heat-flux, thermal gradient approach for testing the coatings will be described. Thermal cyclic behavior of plasma-sprayed coating systems, consisting of ZrO2-8wt%Y2O3 thermal barrier and NASA Enabling Propulsion Materials (EPM) Program developed mullite+BSAS/Si type environmental barrier coatings on SiC/SiC ceramic matrix composites, was investigated under thermal gradients using the laser heat-flux rig in conjunction with the furnace thermal cyclic tests in water-vapor environments. The coating sintering and interface damage were assessed by monitoring the real-time thermal conductivity changes during the laser heat-flux tests and by examining the microstructural changes after the tests. The coating failure mechanisms are discussed based on the cyclic test results and are correlated to the sintering, creep, and thermal stress behavior under simulated engine temperature and heat flux conditions.

  1. Probabilistic migration modelling focused on functional barrier efficiency and low migration concepts in support of risk assessment.

    PubMed

    Brandsch, Rainer

    2017-10-01

    Migration modelling provides reliable migration estimates from food-contact materials (FCM) to food or food simulants based on mass-transfer parameters like diffusion and partition coefficients related to individual materials. In most cases, mass-transfer parameters are not readily available from the literature and for this reason are estimated with a given uncertainty. Historically, uncertainty was accounted for by introducing upper limit concepts first, turning out to be of limited applicability due to highly overestimated migration results. Probabilistic migration modelling gives the possibility to consider uncertainty of the mass-transfer parameters as well as other model inputs. With respect to a functional barrier, the most important parameters among others are the diffusion properties of the functional barrier and its thickness. A software tool that accepts distribution as inputs and is capable of applying Monte Carlo methods, i.e., random sampling from the input distributions of the relevant parameters (i.e., diffusion coefficient and layer thickness), predicts migration results with related uncertainty and confidence intervals. The capabilities of probabilistic migration modelling are presented in the view of three case studies (1) sensitivity analysis, (2) functional barrier efficiency and (3) validation by experimental testing. Based on the predicted migration by probabilistic migration modelling and related exposure estimates, safety evaluation of new materials in the context of existing or new packaging concepts is possible. Identifying associated migration risk and potential safety concerns in the early stage of packaging development is possible. Furthermore, dedicated material selection exhibiting required functional barrier efficiency under application conditions becomes feasible. Validation of the migration risk assessment by probabilistic migration modelling through a minimum of dedicated experimental testing is strongly recommended.

  2. Transport systems of serine at the brain barriers and in brain parenchymal cells.

    PubMed

    Kasai, Yasuyuki; Tachikawa, Masanori; Hirose, Shirou; Akanuma, Shin-ichi; Hosoya, Ken-ichi

    2011-07-01

    D-Serine is a co-agonist for NMDA-type glutamate receptors. Although D-serine levels in CSF and interstitial fluid (ISF) affect CNS function, the regulatory system remains to be fully understood. Therefore, the purpose of this study was to investigate d-serine transport across the blood-brain barrier (BBB) and blood-CSF barrier (BCSFB) and in brain parenchymal cells. D-Serine microinjected into the cerebrum was not eliminated, suggesting a negligible contribution of D-serine efflux transport at the BBB. In contrast, D-serine was taken up from the circulating blood across the BBB via a carrier-mediated process. D-Serine elimination clearance from CSF was fourfold greater than that of d-mannitol, which is considered to reflect CSF bulk flow. The characteristics of D-serine uptake by isolated choroid plexus were consistent with those of Na(+)-independent alanine-serine-cysteine transporter 1 (asc-1). Uptake of D-serine by brain slices appeared to occur predominantly via asc-1 and Na(+)-dependent alanine-serine-cysteine transporter 2. These findings suggest that the regulatory system of D-serine levels in ISF and CSF involves (i) asc-1 at the BCSFB, acting as a major pathway of D-serine elimination from the CSF, (ii) blood-to-brain and blood-to-CSF influx transport of D-serine across the BBB and BCSFB, and (iii) concentrative uptake of D-serine by brain parenchymal cells.

  3. Integrating observational and modelling systems for the management of the Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Baird, M. E.; Jones, E. M.; Margvelashvili, N.; Mongin, M.; Rizwi, F.; Robson, B.; Schroeder, T.; Skerratt, J.; Steven, A. D.; Wild-Allen, K.

    2016-02-01

    Observational and modelling systems provide two sources of knowledge that must be combined to provide a more complete view than either observations or models alone can provide. Here we describe the eReefs coupled hydrodynamic, sediment and biogeochemical model that has been developed for the Great Barrier Reef; and the multiple observations that are used to constrain the model. Two contrasting examples of model - observational integration are highlighted. First we explore the carbon chemistry of the waters above the reef, for which observations are accurate, but expensive and therefore sparse, while model behaviour is highly skilful. For carbon chemistry, observations are used to constrain model parameterisation and quantify model error, with the model output itself providing the most useable knowledge for management purposes. In contrast, ocean colour provides inaccurate, but cheap and spatially and temporally extensive observations. Thus observations are best combined with the model in a data assimilating framework, where a custom-designed optical model has been developed for the purposes of incorporating ocean colour observations. The future management of Great Barrier Reef water quality will be based on an integration of observing and modelling systems, providing the most robust information available.

  4. Graphene as a diffusion barrier for isomorphous systems: Cu-Ni system

    NASA Astrophysics Data System (ADS)

    Roy, Apurba; Punith Kumar, M. K.; Srivastava, Chandan

    2016-02-01

    Electrochemical exfoliation technique using the pyrophosphate anion derived from tetra sodium pyrophosphate was employed to produce graphene. As-synthesized graphene was then drop dried over a cold rolled Cu sheet. Ni coating was then electrodeposited over bare Cu and graphene-Cu substrates. Both substrates were then isothermally annealed at 800 °C for 3 h. WDS analysis showed substantial atomic diffusion in annealed Ni-Cu sample. Cu-graphene-Ni sample, on the other hand, showed negligible diffusion illustrating the diffusion barrier property of the graphene coating.

  5. Time and materials needed to survey, inject systemic fungicides, and install root-graft barriers for Dutch elm disease management

    Treesearch

    William N., Jr. Cannon; Jack H. Barger; Charles J. Kostichka; Charles J. Kostichka

    1986-01-01

    Dutch elm disease control practice in 15 communities showed a wide range of time and material required to apply control methods. The median time used for each method was: sanitation survey, 9.8 hours per square mile; symptom survey, 96 hours per thousand elms; systemic fungicide injection, 1.4 hours per elm; and root-graft barrier installation, 2.2 hours per barrier (5...

  6. Application of the "Behind the Barriers" resilience conceptual model to a flooded rail transport system

    NASA Astrophysics Data System (ADS)

    Gonzva, Michael; Barroca, Bruno

    2017-04-01

    The vulnerability of guided transport systems facing natural hazards is a burning issue for the urban risks management. Experience feedbacks on guided transport systems show they are particularly vulnerable to natural risks, especially flood risks. Besides, the resilience concept is used as a systemic approach for making an accurate analysis of the effect of these natural risks on rail guided transport systems. In this context, several conceptual models of resilience are elaborated for presenting the various possible resilience strategies applied to urban technical systems. One of this resilience conceptual model is the so-called "Behind The Barriers" model based on the identification of four complementary types of resilience: (i) cognitive resilience, linked to knowledge of the risk and the potential failures; (ii) functional resilience, representing the capacity of a system to protect itself from damage while continuing to provide services; (iii) correlative resilience, that characterises the relationship between service demand and the capacity of the system to respond; (iv) organisational resilience, expressing the capacity to mobilise an area much wider than the one affected. In addition to the work already published during the 7th Resilience Engineering Symposium, the purpose of this paper is to offer an application of a resilience conceptual model, the "Behind the Barriers" model, relating to a specific urban technical system, the public guided transport system, and facing a particular risk, a flood hazard. To do that, the paper is focused on a past incident on a French Intercity railway line as a studied case. Indeed, on June 18th and 19th 2013, the rise of the level of the "Gave de Pau" river, located in the municipality of Coarraze, caused many disorders on the intercity line serving the cities of Tarbes, Pau and Lourdes . Among the disorders caused by the flooding, about 100 meters of railway embankments were collapsed. With a constraint to reopen the

  7. Regulation of Copper Transport Crossing Brain Barrier Systems by Cu-ATPases: Effect of Manganese Exposure

    PubMed Central

    Fu, Xue; Zhang, Yanshu; Jiang, Wendy; Monnot, Andrew Donald; Bates, Christopher Alexander; Zheng, Wei

    2014-01-01

    Regulation of cellular copper (Cu) homeostasis involves Cu-transporting ATPases (Cu-ATPases), i.e., ATP7A and ATP7B. The question as to how these Cu-ATPases in brain barrier systems transport Cu, i.e., toward brain parenchyma, cerebrospinal fluid (CSF), or blood, remained unanswered. This study was designed to characterize roles of Cu-ATPases in regulating Cu transport at the blood-brain barrier (BBB) and blood-CSF barrier (BCB) and to investigate how exposure to toxic manganese (Mn) altered the function of Cu-ATPases, thereby contributing to the etiology of Mn-induced parkinsonian disorder. Studies by quantitative real-time RT-PCR (qPCR), Western blot, and immunocytochemistry revealed that both Cu-ATPases expressed abundantly in BBB and BCB. Transport kinetic studies by in situ brain infusion and ventriculo-cisternal (VC) perfusion in Sprague Dawley rat suggested that the BBB was a major site for Cu entry into brain, whereas the BCB was a predominant route for Cu efflux from the CSF to blood. Confocal evidence showed that the presence of excess Cu or Mn in the choroid plexus cells led to ATP7A relocating toward the apical microvilli facing the CSF, but ATP7B toward the basolateral membrane facing blood. Mn exposure inhibited the production of both Cu-ATPases. Collectively, these data suggest that Cu is transported by the BBB from the blood to brain, which is mediated by ATP7A in brain capillary. By diffusion, Cu ions move from the interstitial fluid into the CSF, where they are taken up by the BCB. Within the choroidal epithelial cells, Cu ions are transported by ATP7B back to the blood. Mn exposure alters these processes, leading to Cu dyshomeostasis-associated neuronal injury. PMID:24614235

  8. Targeting Palmitoyl acyltransferase ZDHHC21 Improves Gut Epithelial Barrier Dysfunction Resulting from Burn Induced Systemic Inflammation.

    PubMed

    Haines, Ricci J; Wang, Chunyan; Yang, Clement Gy; Eitnier, Rebecca A; Wang, Fang; Wu, Mack H

    2017-08-24

    Clinical studies in burn patients demonstrate a close association between leaky guts and increased incidence or severity of sepsis and other complications. Severe thermal injury triggers intestinal inflammation that contributes to intestinal epithelial hyperpermeability, which exacerbates systemic response leading to multiple organ failure and sepsis. In this study, we identified a significant function of a particular palmitoyl acyltransferase (PAT), ZDHHC21, in mediating signaling events required for gut hyperpermeability induced by inflammation. Using qPCR, we show that ZDHHC21 mRNA, production was enhanced by two-fold when intestinal epithelial cells were treated with TNFα/IFNγ in vitro. In addition, pharmacological targeting of PATs with 2-bromopalmitate (2-BP) showed significant improvement in TNFα/IFNγ mediated epithelial barrier dysfunction by using electric cell-substrate impedance sensing (ECIS) assays, as well as FITC-dextran permeability assays. Using the ABE assay and click chemistry, we show that TNFα/IFNγ treatment of intestinal epithelial cells results in enhanced detection of total palmitoylated proteins, and this response is inhibited by 2-BP. Using ZDHHC21 deficient mice or wild-type mice treated with 2-BP, we showed that mice with impaired ZDHHC21 expression or pharmacological inhibition resulted in attenuated intestinal barrier dysfunction caused by thermal injury. Moreover, H&E staining of small intestine, as well as transmission electron microscopy (TEM), showed mice with genetic interruption of ZDHHC21 had attenuated villus structure disorganization associated with thermal injury induced intestinal barrier damage. Taken together, these results suggest an important role of ZDHHC21 in mediating gut hyperpermeability resulting from thermal injury. Copyright © 2017, American Journal of Physiology-Gastrointestinal and Liver Physiology.

  9. In Vitro and Ex Vivo Model Systems to Measure ABC Transporter Activity at the Blood-Brain Barrier.

    PubMed

    de Wit, Nienke M; Kooij, Gijs; de Vries, Helga E

    2016-01-01

    With the aging population the occurrence of central nervous system diseases such as cancer, mental disorders and neurodegenerative diseases, is expected to increase and hence, the demand for effective drugs. However, the passage of drugs across the blood-brain barrier represents a major challenge in accomplishing efficient brain delivery of therapeutic agents. This highly efficient barrier is composed of a monolayer of capillary endothelial cells supported by pericytes and astrocytic end-feet, that together effectively shield the brain from the blood. The brain microvascular endothelial cells form a physical and metabolic barrier where paracellular and transcellular transport of molecules in and out of the brain is closely regulated, allowing nutrients to pass but preventing the entry of harmful neurotoxic substances, including drugs. For this purpose brain endothelial cells express efficient efflux pumps, such as ATP binding cassette (ABC) transporters, which limit the delivery of drugs into the brain. To treat the above-mentioned chronic central nervous system disorders, it is crucial to design compounds that can pass the blood-brain barrier and thus the ABC transporters. In order to achieve this, representative models of the blood-brain barrier with predictive validity are necessary. This review discusses the current in vitro and ex vivo model systems that are used to measure ABC transporter activity in order to study potential in vivo efficacy of blood-brain barrier-drug passage.

  10. Understanding the system in risk assessment

    SciTech Connect

    Craft, R.; Vandewart, R.; Wyss, G.; Funkhouser, D.

    1998-02-01

    In the assessment of a system, understanding the system is central. Even so, most of the current literature takes a narrow view of understanding, making only the catalog of system ``assets`` explicit, while maintaining the balance of the analyst`s understanding inside the analyst`s head. This can lead to problems with non-repeatability and incompleteness of assessment results. This paper introduces the notion of using explicit system models to document the analyst`s understanding of the system and shows that, from these models, standard assessment products, such as fault trees and event trees, can be automatically derived. This paper also presents five ``views`` of a system that can be used to document the analyst`s understanding of the system. These views go well beyond the standard instruction to identify the system`s assets to show that a much richer understanding of the system can be required for effective assessment.

  11. The Landsat-D Assessment System

    NASA Technical Reports Server (NTRS)

    Bracken, P. A.; Billingsley, J. B.; Lynch, T. J.; Quann, J. J.

    1979-01-01

    The overall Landsat-D system is discussed with emphasis on the objectives, configuration, and capabilities of the Landsat-D Assessment System. This system is being developed to support investigations which demonstrate, evaluate, and assess the utility of Landsat-D data for a wide variety of earth observations applications.

  12. A gut-vascular barrier controls the systemic dissemination of bacteria.

    PubMed

    Spadoni, Ilaria; Zagato, Elena; Bertocchi, Alice; Paolinelli, Roberta; Hot, Edina; Di Sabatino, Antonio; Caprioli, Flavio; Bottiglieri, Luca; Oldani, Amanda; Viale, Giuseppe; Penna, Giuseppe; Dejana, Elisabetta; Rescigno, Maria

    2015-11-13

    In healthy individuals, the intestinal microbiota cannot access the liver, spleen, or other peripheral tissues. Some pathogenic bacteria can reach these sites, however, and can induce a systemic immune response. How such compartmentalization is achieved is unknown. We identify a gut-vascular barrier (GVB) in mice and humans that controls the translocation of antigens into the blood stream and prohibits entry of the microbiota. Salmonella typhimurium can penetrate the GVB in a manner dependent on its pathogenicity island (Spi) 2-encoded type III secretion system and on decreased β-catenin-dependent signaling in gut endothelial cells. The GVB is modified in celiac disease patients with elevated serum transaminases, which indicates that GVB dismantling may be responsible for liver damage in these patients. Understanding the GVB may provide new insights into the regulation of the gut-liver axis.

  13. Advanced Oxide Material Systems for 1650 C Thermal/Environmental Barrier Coating Applications

    NASA Technical Reports Server (NTRS)

    Zhu, Dong-Ming; Fox, Dennis S.; Bansal, Narottam P.; Miller, Robert A.

    2004-01-01

    Advanced thermal and environmental barrier coatings (TEBCs) are being developed for low-emission SiC/SiC ceramic matrix composite (CMC) combustor and vane applications to extend the CMC liner and vane temperature capability to 1650 C (3000 F) in oxidizing and water-vapor-containing combustion environments. The advanced 1650 C TEBC system is required to have a better high-temperature stability, lower thermal conductivity, and more resistance to sintering and thermal stress than current coating systems under engine high-heat-flux and severe thermal cycling conditions. In this report, the thermal conductivity and water vapor stability of selected candidate hafnia-, pyrochlore- and magnetoplumbite-based TEBC materials are evaluated. The effects of dopants on the materials properties are also discussed. The test results have been used to downselect the TEBC materials and help demonstrate the feasibility of advanced 1650 C coatings with long-term thermal cycling durability.

  14. Detection of hydroxyl radicals during regeneration of granular activated carbon in dielectric barrier discharge plasma system

    NASA Astrophysics Data System (ADS)

    Tang, Shoufeng; Lu, Na; Shang, Kefeng; Li, Jie; Wu, Yan

    2013-03-01

    To understand the reactions taking place in the dielectric barrier discharge (DBD) plasma system of activated carbon regeneration, the determination of active species is necessary. A method based on High Performance Liquid Chromatography with radical trapping by salicylic acid, has been developed to measure hydroxyl radical (•OH) in the DBD plasma reactor. The effects of applied voltage, treatment time, and gas flow rate and atmosphere were investigated. Experimental results indicated that increasing voltage, treatment time and air flow rate could enhance the formation of •OH. Oxygen atmosphere and a suitable GAC water content were contributed to •OH generation. The results give an insight into plasma chemical processes, and can be helpful to optimize the design and application for the plasma system.

  15. Advanced Oxide Material Systems For 1650 C Thermal/Environmental Barrier Coating Applications

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Fox, Dennis S.; Bansal, Narottam P.; Miller, Robert A.

    2004-01-01

    Advanced thermal/environmental barrier coatings (T/EBCs) are being developed for low emission SiC/SiC ceramic matrix composite (CMC) combustor and vane applications to extend the CMC liner and vane temperature capability to 1650 C (3000 F) in oxidizing and water-vapor containing combustion environments. The 1650 C T/EBC system is required to have better thermal stability, lower thermal conductivity, and improved sintering and thermal stress resistance than current coating systems. In this paper, the thermal conductivity, water vapor stability and cyclic durability of selected candidate zirconia-/hafnia-, pyrochlore- and magnetoplumbite-based T/EBC materials are evaluated. The test results have been used to downselect the T/EBC coating materials, and help demonstrate advanced 1650OC coatings feasibility with long-term cyclic durability.

  16. Barriers to appropriate care for mothers and infants during the perinatal period in rural Afghanistan: A qualitative assessment

    PubMed Central

    Newbrander, William; Natiq, Kayhan; Shahim, Shafiqullah; Hamid, Najibullah; Skena, Naomi Brill

    2013-01-01

    This study, conducted in five rural districts in Afghanistan, used qualitative methods to explore traditional practices of women, families and communities related to maternal and newborn care, and sociocultural and health system issues that create access barriers. The traditional practices discussed include delayed bathing of mothers and delayed breastfeeding of infants, seclusion of women after childbirth, restricted maternal diet, and use of traditional home remedies and self-medication instead of care in health facilities to treat maternal and newborn conditions. This study also looked at community support structures, transportation and care-seeking behaviour for maternal and newborn problems which create access barriers. Sociocultural barriers to better maternal-newborn health include shame about utilisation of maternal and neonatal services, women's inability to seek care without being accompanied by a male relative, and care-seeking from mullahs for serious health concerns. This study also found a high level of post-partum depression. Targeted and more effective behaviour-change communication programmes are needed. This study presents a set of behaviour-change messages to reduce maternal and newborn mortality associated with births occurring at home in rural communities. This study recommends using religious leaders, trained health workers, family health action groups and radio to disseminate these messages. PMID:24003851

  17. Preventing childhood obesity through state policy: qualitative assessment of enablers and barriers.

    PubMed

    Dodson, Elizabeth A; Fleming, Chris; Boehmer, Tegan K; Haire-Joshu, Debra; Luke, Douglas A; Brownson, Ross C

    2009-01-01

    As the prevalence of obesity rapidly climbs among youth in the United States, public health practitioners and policymakers seek effective means of slowing and reversing these trends. Recently, many state laws and regulations addressing childhood obesity have been introduced and enacted. Understanding determinants of such legislation may inform the development and passage of future policies. For this study, key-informant interviews were conducted with 16 legislators and staffers from 11 states in 2005-2006 to examine qualitative factors that enable and impede state-level childhood obesity prevention legislation. Commonly cited factors positively influencing the passage of childhood obesity prevention legislation included national media exposure, introduction of the policy by senior legislators, and gaining the support of key players including parents, physicians, and schools. Noteworthy barriers included powerful lobbyists of companies that produce unhealthy foods and misconceptions about legislating foods at schools. Although the total number of informants was modest, their valuable insights provide policymakers and practitioners with a set of enablers and barriers to be considered when pursuing state-level policy.

  18. Assessing Barriers to the Use of Fall Protection in Small Residential Construction Companies in New Jersey.

    PubMed

    Borjan, Marija; Patel, Toral; Lefkowitz, Daniel; Campbell, Carla; Lumia, Margaret

    2016-05-01

    Three focus groups were conducted with residential construction workers from local New Jersey labor organizations to characterize barriers to fall protection use among residential construction contractors who work for companies with fewer than ten employees. Thirty-six residential construction workers volunteered to participate, the average age was thirty-nine years, and twenty-four (67%) were of Hispanic origin. Twelve (33%) of the participants reported having fallen from greater than 6 ft at work and twenty (56%) of the participants had known someone who has fallen from greater than 6 ft. Sixteen (44%) had not been provided with fall protection equipment by their employer and eighteen (50%) reported their current employer had not provided workplace safety training. Factors that created barriers to use of fall protection equipment such as equipment availability, employee/employer relationships, cultural differences, and company size were identified. Results from this study confirm that falls remain a concern among residential construction workers in small companies. © The Author(s) 2015.

  19. Understanding Barriers and Facilitators to the use of Clinical Information Systems for Intensive Care Units and Anesthesia Record Keeping: A Rapid Ethnography

    PubMed Central

    Saleem, Jason J.; Plew, William R.; Speir, Ross C.; Herout, Jennifer; Wilck, Nancy R.; Ryan, Dale Marie; Cullen, Theresa A.; Scott, Jean M.; Beene, Murielle S.; Phillips, Toni

    2017-01-01

    Objective This study evaluated the current use of commercial-off-the-shelf Clinical Information Systems (CIS) for intensive care units (ICU) and Anesthesia Record Keeping (ARK) for operating rooms and post-anesthesia care recovery settings at three Veterans Affairs Medical Centers (VAMCs). Clinicians and administrative staff use these applications at bedside workstations, in operating rooms, at nursing stations, in physician’s rooms, and in other various settings. The intention of a CIS or an ARK system is to facilitate creation of electronic records of data, assessments, and procedures from multiple medical devices. The US Department of Veterans Affairs (VA) Office of the Chief of Nursing Informatics sought to understand usage barriers and facilitators to optimize these systems in the future. Therefore, a human factors study was carried out to observe the CIS and ARK systems in use at three VAMCs in order to identify best practices and suggested improvements to currently implemented CIS and ARK systems. Methods We conducted a rapid ethnographic study of clinical end-users interacting with the CIS and ARK systems in the critical care and anesthesia care areas in each of three geographically distributed VAMCs. Two observers recorded interactions and/or interview responses from 88 CIS and ARK end-users. We coded and sorted into logical categories field notes from 69 shadowed participants. The team transcribed and combined data from key informant interviews with 19 additional participants with the observation data. We then integrated findings across observations into meaningful patterns and abstracted the data into themes, which translated directly to barriers to effective adoption and optimization of the CIS and ARK systems. Results Effective optimization of the CIS and ARK systems was impeded by: (1) integration issues with other software systems; (2) poor usability; (3) software challenges; (4) hardware challenges; (5) training concerns; (6) unclear roles and

  20. Understanding barriers and facilitators to the use of Clinical Information Systems for intensive care units and Anesthesia Record Keeping: A rapid ethnography.

    PubMed

    Saleem, Jason J; Plew, William R; Speir, Ross C; Herout, Jennifer; Wilck, Nancy R; Ryan, Dale Marie; Cullen, Theresa A; Scott, Jean M; Beene, Murielle S; Phillips, Toni

    2015-07-01

    This study evaluated the current use of commercial-off-the-shelf Clinical Information Systems (CIS) for intensive care units (ICUs) and Anesthesia Record Keeping (ARK) for operating rooms and post-anesthesia care recovery settings at three Veterans Affairs Medical Centers (VAMCs). Clinicians and administrative staff use these applications at bedside workstations, in operating rooms, at nursing stations, in physician's rooms, and in other various settings. The intention of a CIS or an ARK system is to facilitate creation of electronic records of data, assessments, and procedures from multiple medical devices. The US Department of Veterans Affairs (VA) Office of the Chief of Nursing Informatics sought to understand usage barriers and facilitators to optimize these systems in the future. Therefore, a human factors study was carried out to observe the CIS and ARK systems in use at three VAMCs in order to identify best practices and suggested improvements to currently implemented CIS and ARK systems. We conducted a rapid ethnographic study of clinical end-users interacting with the CIS and ARK systems in the critical care and anesthesia care areas in each of three geographically distributed VAMCs. Two observers recorded interactions and/or interview responses from 88 CIS and ARK end-users. We coded and sorted into logical categories field notes from 69 shadowed participants. The team transcribed and combined data from key informant interviews with 19 additional participants with the observation data. We then integrated findings across observations into meaningful patterns and abstracted the data into themes, which translated directly to barriers to effective adoption and optimization of the CIS and ARK systems. Effective optimization of the CIS and ARK systems was impeded by: (1) integration issues with other software systems; (2) poor usability; (3) software challenges; (4) hardware challenges; (5) training concerns; (6) unclear roles and lack of coordination among

  1. Comparing the Dimensions of Modern and Ancient Barrier Island Systems to Understand Controls on Preservation

    NASA Astrophysics Data System (ADS)

    Mulhern, J.; Johnson, C. L.; Stright, L.

    2015-12-01

    Commonly assumed to have low preservation potential, barrier islands are rarely interpreted in the rock record, and there is little consensus on the terminology and depositional models related to their interpretation. Prevalent on transgressive coastlines, the dimensions of modern barriers are used as analogs for the ancient; however, ancient examples are complicated by post-depositional processes, including thickening through amalgamation and removal by ravinement. Contrasting the dimensions of modern and ancient examples lends insight into the development and preservation of transgressive deposits, improving the ability to predict the size and distribution of barrier island sand bodies in the rock record as well as understanding the variables that control their architecture. Interpretation of barrier island deposits from the John Henry Member (Cretaceous Straight Cliffs Fm., Kaiparowits Plateau, southern Utah) motivated an investigation into both ancient and modern barrier islands. Traditional sequence stratigraphic models predict thin condensed deposition during transgression, not accounting for possible thick and laterally extensive accumulations of barrier island deposits. More recent models recognize the possible complexity and heterogeneity of transgressive deposits and the potential for barrier island accumulation. To better understand the relationship between modern and ancient barrier islands, the length (along strike), width (dip direction) and thickness (vertical) of >20 modern and >30 ancient barrier islands were compared. Ancient dimensions were gathered from the literature, while modern dimensions were aggregated from literature and a database of modern barrier islands currently being developed. Initial results suggest that ancient barrier island deposits record the motion of the shoreline during transgression. Ancient barriers are ~2-8 times wider and ~2-3 times thicker than modern islands. The dynamics of barrier island migration and sediment

  2. Assessment in Higher Education: Drivers, Barriers and Directions for Change in the UK

    ERIC Educational Resources Information Center

    Medland, Emma

    2016-01-01

    Assessment is fundamental to student learning and achievement. However, whilst research consistently emphasises the role of assessment in supporting the development of the learner, the reality of assessment processes and practices in higher education is frequently indicated to fall someway short. This article aims to contribute to a shared…

  3. Assessment in Higher Education: Drivers, Barriers and Directions for Change in the UK

    ERIC Educational Resources Information Center

    Medland, Emma

    2016-01-01

    Assessment is fundamental to student learning and achievement. However, whilst research consistently emphasises the role of assessment in supporting the development of the learner, the reality of assessment processes and practices in higher education is frequently indicated to fall someway short. This article aims to contribute to a shared…

  4. Monitoring Local Strain in a Thermal Barrier Coating System Under Thermal Mechanical Gas Turbine Operating Conditions

    NASA Astrophysics Data System (ADS)

    Manero, Albert; Sofronsky, Stephen; Knipe, Kevin; Meid, Carla; Wischek, Janine; Okasinski, John; Almer, Jonathan; Karlsson, Anette M.; Raghavan, Seetha; Bartsch, Marion

    2015-07-01

    Advances in aircraft and land-based turbine engines have been increasing the extreme loading conditions on traditional engine components and have incited the need for improved performance with the use of protective coatings. These protective coatings shield the load-bearing super alloy blades from the high-temperature combustion gases by creating a thermal gradient over their thickness. This addition extends the life and performance of blades. A more complete understanding of the behavior, failure mechanics, and life expectancy for turbine blades and their coatings is needed to enhance and validate simulation models. As new thermal-barrier-coated materials and deposition methods are developed, strides to effectively test, evaluate, and prepare the technology for industry deployment are of paramount interest. Coupling the experience and expertise of researchers at the University of Central Florida, The German Aerospace Center, and Cleveland State University with the world-class synchrotron x-ray beam at the Advanced Photon Source in Argonne National Laboratory, the synergistic collaboration has yielded previously unseen measurements to look inside the coating layer system for in situ strain measurements during representative service loading. These findings quantify the in situ strain response on multilayer thermal barrier coatings and shed light on the elastic and nonelastic properties of the layers and the role of mechanical load and internal cooling variations on the response. The article discusses the experimental configuration and development of equipment to perform in situ strain measurements on multilayer thin coatings and provides an overview of the achievements thus far.

  5. Ultrathin, transferred layers of thermally grown silicon dioxide as biofluid barriers for biointegrated flexible electronic systems

    NASA Astrophysics Data System (ADS)

    Fang, Hui; Zhao, Jianing; Yu, Ki Jun; Song, Enming; Barati Farimani, Amir; Chiang, Chia-Han; Jin, Xin; Xue, Yeguang; Xu, Dong; Du, Wenbo; Seo, Kyung Jin; Zhong, Yiding; Yang, Zijian; Won, Sang Min; Fang, Guanhua; Choi, Seo Woo; Chaudhuri, Santanu; Huang, Yonggang; Ashraful Alam, Muhammad; Viventi, Jonathan; Aluru, N. R.; Rogers, John A.

    2016-10-01

    Materials that can serve as long-lived barriers to biofluids are essential to the development of any type of chronic electronic implant. Devices such as cardiac pacemakers and cochlear implants use bulk metal or ceramic packages as hermetic enclosures for the electronics. Emerging classes of flexible, biointegrated electronic systems demand similar levels of isolation from biofluids but with thin, compliant films that can simultaneously serve as biointerfaces for sensing and/or actuation while in contact with the soft, curved, and moving surfaces of target organs. This paper introduces a solution to this materials challenge that combines (i) ultrathin, pristine layers of silicon dioxide (SiO2) thermally grown on device-grade silicon wafers, and (ii) processing schemes that allow integration of these materials onto flexible electronic platforms. Accelerated lifetime tests suggest robust barrier characteristics on timescales that approach 70 y, in layers that are sufficiently thin (less than 1 μm) to avoid significant compromises in mechanical flexibility or in electrical interface fidelity. Detailed studies of temperature- and thickness-dependent electrical and physical properties reveal the key characteristics. Molecular simulations highlight essential aspects of the chemistry that governs interactions between the SiO2 and surrounding water. Examples of use with passive and active components in high-performance flexible electronic devices suggest broad utility in advanced chronic implants.

  6. Ultrathin, transferred layers of thermally grown silicon dioxide as biofluid barriers for biointegrated flexible electronic systems.

    PubMed

    Fang, Hui; Zhao, Jianing; Yu, Ki Jun; Song, Enming; Farimani, Amir Barati; Chiang, Chia-Han; Jin, Xin; Xue, Yeguang; Xu, Dong; Du, Wenbo; Seo, Kyung Jin; Zhong, Yiding; Yang, Zijian; Won, Sang Min; Fang, Guanhua; Choi, Seo Woo; Chaudhuri, Santanu; Huang, Yonggang; Alam, Muhammad Ashraful; Viventi, Jonathan; Aluru, N R; Rogers, John A

    2016-10-18

    Materials that can serve as long-lived barriers to biofluids are essential to the development of any type of chronic electronic implant. Devices such as cardiac pacemakers and cochlear implants use bulk metal or ceramic packages as hermetic enclosures for the electronics. Emerging classes of flexible, biointegrated electronic systems demand similar levels of isolation from biofluids but with thin, compliant films that can simultaneously serve as biointerfaces for sensing and/or actuation while in contact with the soft, curved, and moving surfaces of target organs. This paper introduces a solution to this materials challenge that combines (i) ultrathin, pristine layers of silicon dioxide (SiO2) thermally grown on device-grade silicon wafers, and (ii) processing schemes that allow integration of these materials onto flexible electronic platforms. Accelerated lifetime tests suggest robust barrier characteristics on timescales that approach 70 y, in layers that are sufficiently thin (less than 1 μm) to avoid significant compromises in mechanical flexibility or in electrical interface fidelity. Detailed studies of temperature- and thickness-dependent electrical and physical properties reveal the key characteristics. Molecular simulations highlight essential aspects of the chemistry that governs interactions between the SiO2 and surrounding water. Examples of use with passive and active components in high-performance flexible electronic devices suggest broad utility in advanced chronic implants.

  7. Ultrathin, transferred layers of thermally grown silicon dioxide as biofluid barriers for biointegrated flexible electronic systems

    PubMed Central

    Fang, Hui; Yu, Ki Jun; Song, Enming; Farimani, Amir Barati; Chiang, Chia-Han; Jin, Xin; Xu, Dong; Du, Wenbo; Seo, Kyung Jin; Zhong, Yiding; Yang, Zijian; Won, Sang Min; Fang, Guanhua; Choi, Seo Woo; Chaudhuri, Santanu; Huang, Yonggang; Alam, Muhammad Ashraful; Viventi, Jonathan; Aluru, N. R.; Rogers, John A.

    2016-01-01

    Materials that can serve as long-lived barriers to biofluids are essential to the development of any type of chronic electronic implant. Devices such as cardiac pacemakers and cochlear implants use bulk metal or ceramic packages as hermetic enclosures for the electronics. Emerging classes of flexible, biointegrated electronic systems demand similar levels of isolation from biofluids but with thin, compliant films that can simultaneously serve as biointerfaces for sensing and/or actuation while in contact with the soft, curved, and moving surfaces of target organs. This paper introduces a solution to this materials challenge that combines (i) ultrathin, pristine layers of silicon dioxide (SiO2) thermally grown on device-grade silicon wafers, and (ii) processing schemes that allow integration of these materials onto flexible electronic platforms. Accelerated lifetime tests suggest robust barrier characteristics on timescales that approach 70 y, in layers that are sufficiently thin (less than 1 μm) to avoid significant compromises in mechanical flexibility or in electrical interface fidelity. Detailed studies of temperature- and thickness-dependent electrical and physical properties reveal the key characteristics. Molecular simulations highlight essential aspects of the chemistry that governs interactions between the SiO2 and surrounding water. Examples of use with passive and active components in high-performance flexible electronic devices suggest broad utility in advanced chronic implants. PMID:27791052

  8. Progress report for project modeling Arctic barrier island-lagoon system response to projected Arctic warming

    USGS Publications Warehouse

    Erikson, Li H.; Gibbs, Ann E.; Richmond, Bruce M.; Storlazzi, Curt; B.M. Jones,

    2012-01-01

    Changes in Arctic coastal ecosystems in response to global warming may be some of the most severe on the planet. A better understanding and analysis of the rates at which these changes are expected to occur over the coming decades is crucial in order to delineate high-priority areas that are likely to be affected by climate changes. In this study we investigate the likelihood of changes to habitat-supporting barrier island – lagoon systems in response to projected changes in atmospheric and oceanographic forcing associated with Arctic warming. To better understand the relative importance of processes responsible for the current and future coastal landscape, key parameters related to increasing arctic temperatures are investigated and used to establish boundary conditions for models that simulate barrier island migration and inundation of deltaic deposits and low-lying tundra. The modeling effort investigates the dominance and relative importance of physical processes shaping the modern Arctic coastline as well as decadal responses due to projected conditions out to the year 2100.

  9. Pathways for Small Molecule Delivery to the Central Nervous System Across the Blood-Brain Barrier

    PubMed Central

    Mikitsh, John L; Chacko, Ann-Marie

    2014-01-01

    The treatment of central nervous system (CNS) disease has long been difficult due to the ineffectiveness of drug delivery across the blood-brain barrier (BBB). This review summarizes important concepts of the BBB in normal versus pathophysiology and how this physical, enzymatic, and efflux barrier provides necessary protection to the CNS during drug delivery, and consequently treatment challenging. Small molecules account for the vast majority of available CNS drugs primarily due to their ability to penetrate the phospholipid membrane of the BBB by passive or carrier-mediated mechanisms. Physiochemical and biological factors relevant for designing small molecules with optimal capabilities for BBB permeability are discussed, as well as the most promising classes of transporters suitable for small-molecule drug delivery. Clinically translatable imaging methodologies for detecting and quantifying drug uptake and targeting in the brain are discussed as a means of further understanding and refining delivery parameters for both drugs and imaging probes in preclinical and clinical domains. This information can be used as a guide to design drugs with preserved drug action and better delivery profiles for improved treatment outcomes over existing therapeutic approaches. PMID:24963272

  10. Effectiveness of compacted soil liner as a gas barrier layer in the landfill final cover system.

    PubMed

    Moon, Seheum; Nam, Kyoungphile; Kim, Jae Young; Hwan, Shim Kyu; Chung, Moonkyung

    2008-01-01

    A compacted soil liner (CSL) has been widely used as a single barrier layer or a part of composite barrier layer in the landfill final cover system to prevent water infiltration into solid wastes for its acceptable hydraulic permeability. This study was conducted to test whether the CSL was also effective in prohibiting landfill gas emissions. For this purpose, three different compaction methods (i.e., reduced, standard, and modified Proctor methods) were used to prepare the soil specimens, with nitrogen as gas, and with water and heptane as liquid permeants. Measured gas permeability ranged from 2.03 x 10(-10) to 4.96 x 10(-9) cm(2), which was a magnitude of two or three orders greater than hydraulic permeability (9.60 x 10(-13) to 1.05 x 10(-11) cm(2)). The difference between gas and hydraulic permeabilities can be explained by gas slippage, which makes gas more permeable, and by soil-water interaction, which impedes water flow and then makes water less permeable. This explanation was also supported by the result that a liquid permeability measured with heptane as a non-polar liquid was similar to the intrinsic gas permeability. The data demonstrate that hydraulic requirement for the CSL is not enough to control the gas emissions from a landfill.

  11. Interim Results of a National Test of the Rapid Assessment of Hospital Procurement Barriers in Donation (RAPiD)

    PubMed Central

    Traino, H. M.; Alolod, G. P.; Shafer, T.; Siminoff, L. A.

    2012-01-01

    Organ donation remains a major public health challenge with over 114 000 people on the waitlist in the United States. Among other factors, extant research highlights the need to improve the identification and timely referral of potential donors by hospital health-care providers (HCPs) to organ procurement organizations (OPOs). We implemented a national test of the Rapid Assessment of hospital Procurement barriers in Donation (RAPiD) to identify assets and barriers to the organ donation and patient referral processes; assess hospital–OPO relationships and offer tailored recommendations for improving these processes. Having partnered with seven OPOs, data were collected at 70 hospitals with high donor potential in the form of direct observations and interviews with 2358 HCPs. We found that donation attitudes and knowledge among HCPs were high, but use of standard referral criteria was lacking. Significant differences were found in the donation-related attitudes, knowledge and behaviors of physicians and emergency department staff as compared to other staff in intensive care units with high organ donor potential. Also, while OPO staff were generally viewed positively, they were often perceived as outsiders rather than members of healthcare teams. Recommendations for improving the referral and donation processes are discussed. PMID:22900761

  12. Protection against malevolent use of vehicles at Nuclear Power Plants. Vehicle barrier system selection guidance

    SciTech Connect

    Nebuda, D.T.

    1994-08-01

    This manual provides a simplified procedure for selecting land vehicle barriers that will stop the design basis vehicle threat adopted by the U.S. Nuclear Regulatory Commission. Proper selection and construction of vehicle barriers should prevent intrusion of the design basis vehicle. In addition, vital safety related equipment should survive a design basis vehicle bomb attack when vehicle barriers are properly selected, sited, and constructed. This manual addresses passive vehicle barriers, active vehicle barriers, and site design features that can be used to reduce vehicle impact velocity.

  13. Burning Invariant Manifold Theory and the Bipartite Digraph Representation of Generalized Dynamical System Formed by One-way Barriers

    NASA Astrophysics Data System (ADS)

    Li, John; Mahoney, John; Mitchell, Kevin; Solomon, Tom

    2013-11-01

    The recently developed Burning Invariant Manifold (BIM) theory took a dynamical system approach to understand front propagation in Advection-Reaction-Diffusion systems and successfully predicted both the short-term and asymptotic front behavior by finding the unstable BIMs which act as barriers to front propagation. Unlike separatrices in traditional dynamical system being two-way barriers, the BIMs are one-way barriers. This asymmetry gives rise to a much richer dynamical behavior than traditional dynamical systems. Through numerical simulations, we found that the stable BIMs are the basin boundaries. Based on the properties of BIM theory, we further derived a theory to investigate a dynamical system consists of one-way barriers and the cooperative behavior of these barriers. This theory reveals the global structure of both stable and unstable BIMs by first using a systematic algorithm to convert the flow to a bipartite digraph and then extracting information of the steady states of fronts and corresponding basins of attraction from the digraph. This work was supported by the US National Science Foundation under grant PHY-0748828 and NSF Fellowship DGE-0937362.

  14. Role of energy dependent interaction potential in sub-barrier fusion of S2814i +Z9040r system

    NASA Astrophysics Data System (ADS)

    Gautam, Manjeet Singh; Sharma, Manoj K.

    2015-08-01

    We have analyzed the importance of the inelastic surface vibrations of colliding nuclei in the sub-barrier fusion enhancement of S2814i +Z9040r system by using the energy dependent Woods-Saxon potential model (EDWSP model) in conjunction with one dimensional Wong formula and the coupled channel formulation using the code CCFULL. The multi-phonon vibrational states of colliding nuclei seem to impart significant contribution. The coupling between relative motion of reactants and these relevant channels in turn produce anomalously large sub-barrier fusion enhancement over the expectations of one dimensional barrier penetration model. Furthermore, the effects of coupling to inelastic surface excitations are imitated due to energy dependence in the Woods-Saxon potential. In EDWSP model calculations, a wide range of diffuseness parameter much larger than the elastic scattering predictions is needed to account the observed fusion enhancement in the close vicinity of Coulomb barrier.

  15. Advanced vehicle systems assessment. Volume 2: Subsystems assessment

    NASA Technical Reports Server (NTRS)

    Hardy, K.

    1985-01-01

    Volume 2 (Subsystems Assessment) is part of a five-volume report entitled Advanced Vehicle Systems Assessment. Volume 2 presents the projected performance capabilities and cost characteristics of applicable subsystems, considering an additional decade of development. Subsystems of interest include energy storage and conversion devices as well as the necessary powertrain components and vehicle subsystems. Volume 2 also includes updated battery information based on the assessment of an independent battery review board (with the aid of subcontractor reports on advanced battery characteristics).

  16. Assessing the potential underestimation of sediment and nutrient loads to the Great Barrier Reef lagoon during floods.

    PubMed

    Wallace, Jim; Karim, Fazlul; Wilkinson, Scott

    2012-01-01

    Much of the sediment and nutrient load to the Great Barrier Reef (GBR) lagoon happens during over bank floods, when discharge can be significantly underestimated by standard river gauges. This paper assesses the potential need for a flood load correction for 28 coastal rivers that discharge into the GBR lagoon. For each river, daily discharge was divided into flows above and below a 'flood' threshold to calculate the mean annual percentage flow above this threshold. Most GBR rivers potentially need a flood load correction as over 15% of their mean annual flow occurs above the minor flood level; only seven rivers need little/no correction as their flood flows were less than 5% of the mean annual flow. Improved assessment of the true load of materials to the GBR lagoon would be an important contribution to the monitoring and reporting of progress towards Reef Plan and associated marine load targets. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. The Great Barrier Reef Ocean Observing System Mooring array: Monitoring the Western Boundary Currents of the Coral Sea and Impacts on the Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Steinberg, C. R.; McAllister, F.; Brinkman, B. W.; Pitcher, C.; Luetchford, J.; Rigby, P.

    2009-05-01

    Since 1987 Great Barrier Reef weather and water temperature observations have been transmitted in near real time using HF radio from pontoons or towers on coral reefs by AIMS. In contrast oceanographic measurements have however been restricted to loggers serviced at quarterly to half yearly downloads. The Great Barrier Reef Ocean Observing System (GBROOS) is a regional node of the Integrated Marine Observing System (IMOS). IMOS is an Australian Government initiative established under the National Collaborative Research Infrastructure Strategy and has been supported by Queensland Government since 2006. GBROOS comprises real time observations from weather stations, oceanographic moorings, underway ship observations, ocean surface radar, satellite image reception and reef based sensor networks. This paper focuses on an array of in-line moorings that have been deployed along the outer Great Barrier Reef in order to monitor the Western Boundary currents of the Coral Sea. The Westward flowing Southern Equatorial Current bifurcates into the poleward flowing East Australian Current and the equatorward North Queensland Current. The 4 mooring pairs consist of a continental slope mooring, nominally in 200m of water and one on the outer continental shelf within the GBR matrix in depths of 30 to 70m. The array is designed to detect any changes in circulation, temperature response, mixed layer depth and ocean-shelf interactions. A review of likely impacts of climate change on the physical oceanography of the GBR is providing a basis upon which to explore what processes may be affected by climate change. Sample data and results from the initial year of observations will be presented.

  18. Minimizing Barriers in Learning for On-Call Radiology Residents-End-to-End Web-Based Resident Feedback System.

    PubMed

    Choi, Hailey H; Clark, Jennifer; Jay, Ann K; Filice, Ross W

    2017-08-24

    Feedback is an essential part of medical training, where trainees are provided with information regarding their performance and further directions for improvement. In diagnostic radiology, feedback entails a detailed review of the differences between the residents' preliminary interpretation and the attendings' final interpretation of imaging studies. While the on-call experience of independently interpreting complex cases is important to resident education, the more traditional synchronous "read-out" or joint review is impossible due to multiple constraints. Without an efficient method to compare reports, grade discrepancies, convey salient teaching points, and view images, valuable lessons in image interpretation and report construction are lost. We developed a streamlined web-based system, including report comparison and image viewing, to minimize barriers in asynchronous communication between attending radiologists and on-call residents. Our system provides real-time, end-to-end delivery of case-specific and user-specific feedback in a streamlined, easy-to-view format. We assessed quality improvement subjectively through surveys and objectively through participation metrics. Our web-based feedback system improved user satisfaction for both attending and resident radiologists, and increased attending participation, particularly with regards to cases where substantive discrepancies were identified.

  19. An assessment of an environmental gradient using coral geochemical records, Whitsunday Islands, Great Barrier Reef, Australia.

    PubMed

    Lewis, S E; Brodie, J E; McCulloch, M T; Mallela, J; Jupiter, S D; Williams, H Stuart; Lough, J M; Matson, E G

    2012-01-01

    Coral cores were collected along an environmental and water quality gradient through the Whitsunday Island group, Great Barrier Reef (Australia), for trace element and stable isotope analysis. The primary aim of the study was to examine if this gradient could be detected in coral records and, if so, whether the gradient has changed over time with changing land use in the adjacent river catchments. Y/Ca was the trace element ratio which varied spatially across the gradient, with concentrations progressively decreasing away from the river mouths. The Ba/Ca and Y/Ca ratios were the only indicators of change in the gradient through time, increasing shortly after European settlement. The Mn/Ca ratio responded to local disturbance related to the construction of tourism infrastructure. Nitrogen isotope ratios showed no apparent trend over time. This study highlights the importance of site selection when using coral records to record regional environmental signals.

  20. Assessment of variations in thermal cycle life data of thermal barrier coated rods

    NASA Astrophysics Data System (ADS)

    Hendricks, R. C.; McDonald, G.

    An analysis of thermal cycle life data for 22 thermal barrier coated (TBC) specimens was conducted. The Zr02-8Y203/NiCrAlY plasma spray coated Rene 41 rods were tested in a Mach 0.3 Jet A/air burner flame. All specimens were subjected to the same coating and subsequent test procedures in an effort to control three parametric groups; material properties, geometry and heat flux. Statistically, the data sample space had a mean of 1330 cycles with a standard deviation of 520 cycles. The data were described by normal or log-normal distributions, but other models could also apply; the sample size must be increased to clearly delineate a statistical failure model. The statistical methods were also applied to adhesive/cohesive strength data for 20 TBC discs of the same composition, with similar results. The sample space had a mean of 9 MPa with a standard deviation of 4.2 MPa.

  1. Uncertainties of α-particle optical potential assessment around and below the Coulomb barrier

    NASA Astrophysics Data System (ADS)

    Avrigeanu, V.; Avrigeanu, M.; Mǎnǎilescu, C.

    2017-06-01

    A competition of the low-energy Coulomb excitation (CE) with the compound nucleus (CN) formation in α-induced reactions below the Coulomb barrier has recently been assumed in order to make possible the description of the latter as well as the α-particle emission by the same optical model (OM) potential. However, we show in the present work that the corresponding partial waves and integration radii provide evidence for the distinct account of the CE cross section and OM total-reaction cross section σR. Thus the largest contribution to CE cross section comes by far from partial waves larger than the ones contributing to the σR values. Finally, effects of statistical model parameters are comparatively discussed.

  2. Quantitative assessment of barriers to the clinical development and adoption of cellular therapies: A pilot study

    PubMed Central

    Rikabi, Sarah; French, Anna; Pinedo-Villanueva, Rafael; Morrey, Mark E; Wartolowska, Karolina; Judge, Andrew; MacLaren, Robert E; Mathur, Anthony; Williams, David J; Wall, Ivan; Birchall, Martin; Reeve, Brock; Atala, Anthony; Barker, Richard W; Cui, Zhanfeng; Furniss, Dominic; Bure, Kim; Snyder, Evan Y; Karp, Jeffrey M; Price, Andrew; Carr, Andrew; Brindley, David A

    2014-01-01

    There has been a large increase in basic science activity in cell therapy and a growing portfolio of cell therapy trials. However, the number of industry products available for widespread clinical use does not match this magnitude of activity. We hypothesize that the paucity of engagement with the clinical community is a key contributor to the lack of commercially successful cell therapy products. To investigate this, we launched a pilot study to survey clinicians from five specialities and to determine what they believe to be the most significant barriers to cellular therapy clinical development and adoption. Our study shows that the main concerns among this group are cost-effectiveness, efficacy, reimbursement, and regulation. Addressing these concerns can best be achieved by ensuring that future clinical trials are conducted to adequately answer the questions of both regulators and the broader clinical community. PMID:25383173

  3. River Protection Project information systems assessment

    SciTech Connect

    JOHNSON, A.L.

    1999-07-28

    The Information Systems Assessment Report documents the results from assessing the Project Hanford Management Contract (PHMC) Hanford Data Integrator 2000 (HANDI 2000) system, Business Management System (BMS) and Work Management System phases (WMS), with respect to the System Engineering Capability Assessment Model (CAM). The assessment was performed in accordance with the expectations stated in the fiscal year (FY) 1999 Performance Agreement 7.1.1, item (2) which reads, ''Provide an assessment report on the selected Integrated Information System by July 31, 1999.'' This report assesses the BMS and WMS as implemented and planned for the River Protection Project (RPP). The systems implementation is being performed under the PHMC HANDI 2000 information system project. The project began in FY 1998 with the BMS, proceeded in FY 1999 with the Master Equipment List portion of the WMS, and will continue the WMS implementation as funding provides. This report constitutes an interim quality assessment providing information necessary for planning RPP's information systems activities. To avoid confusion, HANDI 2000 will be used when referring to the entire system, encompassing both the BMS and WMS. A graphical depiction of the system is shown in Figure 2-1 of this report.

  4. Assessing pre- and post-zygotic barriers between North Atlantic eels (Anguilla anguilla and A. rostrata).

    PubMed

    Jacobsen, M W; Smedegaard, L; Sørensen, S R; Pujolar, J M; Munk, P; Jónsson, B; Magnussen, E; Hansen, M M

    2017-03-01

    Elucidating barriers to gene flow is important for understanding the dynamics of speciation. Here we investigate pre- and post-zygotic mechanisms acting between the two hybridizing species of Atlantic eels: Anguilla anguilla and A. rostrata. Temporally varying hybridization was examined by analyzing 85 species-diagnostic single-nucleotide polymorphisms (SNPs; FST ⩾0.95) in eel larvae sampled in the spawning region in the Sargasso Sea in 2007 (N=92) and 2014 (N=460). We further investigated whether genotypes at these SNPs were nonrandomly distributed in post-F1 hybrids, indicating selection. Finally, we sequenced the mitochondrial ATP6 and nuclear ATP5c1 genes in 19 hybrids, identified using SNP and restriction site associated DNA (RAD) sequencing data, to test a previously proposed hypothesis of cytonuclear incompatibility leading to adenosine triphosphate (ATP) synthase dysfunction and selection against hybrids. No F1 hybrids but only later backcrosses were observed in the Sargasso Sea in 2007 and 2014. This suggests that interbreeding between the two species only occurs in some years, possibly controlled by environmental conditions at the spawning grounds, or that interbreeding has diminished through time as a result of a declining number of spawners. Moreover, potential selection was found at the nuclear and the cytonuclear levels. Nonetheless, one glass eel individual showed a mismatch, involving an American ATP6 haplotype and European ATP5c1 alleles. This contradicted the presence of cytonuclear incompatibility but may be explained by that (1) cytonuclear incompatibility is incomplete, (2) selection acts at a later life stage or (3) other genes are important for protein function. In total, the study demonstrates the utility of genomic data when examining pre- and post-zyotic barriers in natural hybrids.

  5. Microstructure Evolution and Durability of Advanced Environmental Barrier Coating Systems for SiC/SiC Ceramic Matrix Composites

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Evans, Laura J.; McCue, Terry R.; Harder, Bryan

    2016-01-01

    Environmental barrier coated SiC-SiC ceramic matrix composites (CMCs) systems will play a crucial role in next generation turbine engines for hot-section component applications because of their ability to significantly increase engine operating temperatures with improved efficiency, reduce engine weight and cooling requirements. Advanced HfO2 and rare earth silicate environmental barrier coatings (EBCs), along with multicomponent hafnium and rare earth silicide EBC bond coats have been developed. The coating degradation mechanisms in the laboratory simulated engine thermal cycling, and fatigue-creep operating environments are also being investigated. This paper will focus on the microstructural and compositional evolutions of an advanced environmental barrier coating system on a SiC-SiC CMC substrate during the high temperature simulated durability tests, by using a Field Emission Gun Scanning Electron Microscopy, Energy Dispersive Spectroscopy (EDS) and Wavelength Dispersive Spectroscopy (WDS). The effects of Calcium-Magnesium-Alumino-Silicate (CMAS) from road sand or volcano-ash deposits on the degradation mechanisms of the environmental barrier coating systems will also be discussed. The detailed analysis results help understand the EBC-CMC system performance, aiming at the durability improvements to achieve more robust, prime-reliant environmental barrier coatings.

  6. Adaptive NN Control Using Integral Barrier Lyapunov Functionals for Uncertain Nonlinear Block-Triangular Constraint Systems.

    PubMed

    Liu, Yan-Jun; Tong, Shaocheng; Chen, C L Philip; Li, Dong-Juan

    2016-09-19

    A neural network (NN) adaptive control design problem is addressed for a class of uncertain multi-input-multi-output (MIMO) nonlinear systems in block-triangular form. The considered systems contain uncertainty dynamics and their states are enforced to subject to bounded constraints as well as the couplings among various inputs and outputs are inserted in each subsystem. To stabilize this class of systems, a novel adaptive control strategy is constructively framed by using the backstepping design technique and NNs. The novel integral barrier Lyapunov functionals (BLFs) are employed to overcome the violation of the full state constraints. The proposed strategy can not only guarantee the boundedness of the closed-loop system and the outputs are driven to follow the reference signals, but also can ensure all the states to remain in the predefined compact sets. Moreover, the transformed constraints on the errors are used in the previous BLF, and accordingly it is required to determine clearly the bounds of the virtual controllers. Thus, it can relax the conservative limitations in the traditional BLF-based controls for the full state constraints. This conservatism can be solved in this paper and it is for the first time to control this class of MIMO systems with the full state constraints. The performance of the proposed control strategy can be verified through a simulation example.

  7. Medical safety and community practice: necessary elements and barriers to implement a safety learning system.

    PubMed

    O'Beirne, Maeve; Sterling, Pam D

    2009-01-01

    A safety learning system (SLS) is a system that monitors patient safety incident information and analyzes it to develop and implement improvement strategies to increase patient safety. The purpose of this paper is to discuss the necessary elements of a community-based family medicine practice SLS in Alberta Health Services - Calgary zone, and barriers to, and facilitators of, the implementation of this system. An SLS was developed in the research program Medical Safety in Community Practice. To determine the elements necessary to implement an SLS in community-based family medicine practice, we performed a comprehensive literature review, internal investigator discussions and internal investigator and external stakeholder reviews of key design elements. The system is currently being implemented and tested in community-based family practices as part of the program. Steps identified for implementation: included determining key design elements including creating a website and ascertaining a classification system or taxonomy; developing recruitment strategies; establishing an incident analysis methodology; building a knowledge translation strategy; and pursuing sustainability. These elements produced an SLS that is easily incorporated into community-based family medicine clinics.

  8. Using technology to overcome the language barrier: the Cognitive Assessment for Aphasia App.

    PubMed

    Wall, Kylie Janine; Cumming, Toby Borland; Koenig, Sebastian Thomas; Pelecanos, Anita Maria; Copland, David Andrew

    2017-03-08

    We developed and explored the feasibility and user acceptance of the Cognitive Assessment for Aphasia App: a non-immersive virtual reality cognitive assessment for stroke survivors, designed to be inclusive of individuals with aphasia. Participants were assessed on a battery of pen-and-paper cognitive tests and the Cognitive Assessment for Aphasia App. Feasibility was explored by quantifying missing data for test completion, determining user acceptance for the app by measuring participants' preferred testing method, enjoyment and perceived task difficulty and time-taken to complete the test. Sixty-four stroke participants (35 with aphasia, 29 without aphasia) and 32 controls were recruited. Only one participant with aphasia was unable to complete all the Cognitive Assessment for Aphasia App tasks, whereas 13 participants were unable to complete all pen-and-paper tasks. Only 14% of participants preferred the pen-and-paper tests, and preference did not significantly differ between groups. Ninety-five per cent of participants were neutral or enjoyed the app and 4% perceived it to be very difficult. Higher age was negatively associated with user acceptance measures. The study shows preliminary evidence for the Cognitive Assessment for Aphasia App to be a feasible cognitive assessment for stroke survivors with and without aphasia. The app is currently being validated in stroke. Implications for rehabilitation The Cognitive Assessment for Aphasia App is a feasible tool for assessing post-stroke cognition in acute, inpatient rehabilitation and community settings. In research trials examining cognition, individuals with aphasia are often excluded. The Cognitive Assessment for Aphasia App permits the inclusion of these individuals, enhancing generalizability. The Cognitive Assessment for Aphasia App provides an alternative method to assess cognition that is quicker and preferred over standard neuropsychological tests.

  9. Breakup and Elastic Scattering in the {sup 9}Be + {sup 144}Sm system at near barrier energies

    SciTech Connect

    Paes, B.; Garcia, V. N.; Lubian, J.; Gomes, P. R. S.; Padron, I.

    2010-05-21

    Breakup and elastic scattering in the Be + {sup 144}Sm system, at near barrier energies, are investigated. We calculate theoretically the non-capture breakup cross section by performing coupled reaction channel calculations. The energy dependence of the optical potential does not show the usual threshold anomaly found in tightly bound systems.

  10. Design Principles for New Systems of Assessment