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Sample records for persistent contrail occurrence

  1. Basic Diagnosis and Prediction of Persistent Contrail Occurrence using High-resolution Numerical Weather Analyses/Forecasts and Logistic Regression. Part II: Evaluation of Sample Models

    Science.gov (United States)

    Duda, David P.; Minnis, Patrick

    2009-01-01

    Previous studies have shown that probabilistic forecasting may be a useful method for predicting persistent contrail formation. A probabilistic forecast to accurately predict contrail formation over the contiguous United States (CONUS) is created by using meteorological data based on hourly meteorological analyses from the Advanced Regional Prediction System (ARPS) and from the Rapid Update Cycle (RUC) as well as GOES water vapor channel measurements, combined with surface and satellite observations of contrails. Two groups of logistic models were created. The first group of models (SURFACE models) is based on surface-based contrail observations supplemented with satellite observations of contrail occurrence. The second group of models (OUTBREAK models) is derived from a selected subgroup of satellite-based observations of widespread persistent contrails. The mean accuracies for both the SURFACE and OUTBREAK models typically exceeded 75 percent when based on the RUC or ARPS analysis data, but decreased when the logistic models were derived from ARPS forecast data.

  2. Basic Diagnosis and Prediction of Persistent Contrail Occurrence using High-resolution Numerical Weather Analyses/Forecasts and Logistic Regression. Part I: Effects of Random Error

    Science.gov (United States)

    Duda, David P.; Minnis, Patrick

    2009-01-01

    Straightforward application of the Schmidt-Appleman contrail formation criteria to diagnose persistent contrail occurrence from numerical weather prediction data is hindered by significant bias errors in the upper tropospheric humidity. Logistic models of contrail occurrence have been proposed to overcome this problem, but basic questions remain about how random measurement error may affect their accuracy. A set of 5000 synthetic contrail observations is created to study the effects of random error in these probabilistic models. The simulated observations are based on distributions of temperature, humidity, and vertical velocity derived from Advanced Regional Prediction System (ARPS) weather analyses. The logistic models created from the simulated observations were evaluated using two common statistical measures of model accuracy, the percent correct (PC) and the Hanssen-Kuipers discriminant (HKD). To convert the probabilistic results of the logistic models into a dichotomous yes/no choice suitable for the statistical measures, two critical probability thresholds are considered. The HKD scores are higher when the climatological frequency of contrail occurrence is used as the critical threshold, while the PC scores are higher when the critical probability threshold is 0.5. For both thresholds, typical random errors in temperature, relative humidity, and vertical velocity are found to be small enough to allow for accurate logistic models of contrail occurrence. The accuracy of the models developed from synthetic data is over 85 percent for both the prediction of contrail occurrence and non-occurrence, although in practice, larger errors would be anticipated.

  3. Properties of Linear Contrails Detected in 2012 Northern Hemisphere MODIS Imagery

    Science.gov (United States)

    Duda, David P.; Chee, Thad; Khlopenkov, Konstantin; Bedka, Sarah; Spangenberg, Doug; Minnis, Patrick

    2015-01-01

    Observation of linear contrail cirrus coverage and retrieval of their optical properties are valuable data for validating atmospheric climate models that represent contrail formation explicitly. These data can reduce our uncertainty of the regional effects of contrail-generated cirrus on global radiative forcing, and thus improve our estimation of the impact of commercial aviation on climate change. We use an automated contrail detection algorithm (CDA) to determine the coverage of linear persistent contrails over the Northern Hemisphere during 2012. The contrail detection algorithm is a modified form of the Mannstein et al. (1999) method, and uses several channels from thermal infrared MODIS data to reduce the occurrence of false positive detections. A set of contrail masks of varying sensitivity is produced to define the potential range of uncertainty in contrail coverage estimated by the CDA. Global aircraft emissions waypoint data provided by FAA allow comparison of detected contrails with commercial aircraft flight tracks. A pixel-level product based on the advected flight tracks defined by the waypoint data and U-V wind component profiles from the NASA GMAO GEOS-4 reanalysis has been developed to assign a confidence of contrail detection for the contrail mask. To account for possible contrail cirrus missed by the CDA, a post-processing method based on the assumption that pixels adjacent to detected linear contrails will have radiative signatures similar to those of the detected contrails is applied to the Northern Hemisphere data. Results from several months of MODIS observations during 2012 will be presented, representing a near-global climatology of contrail coverage. Linear contrail coverage will be compared with coverage estimates determined previously from 2006 MODIS data.

  4. Do supersonic aircraft avoid contrails?

    Directory of Open Access Journals (Sweden)

    A. Stenke

    2008-02-01

    Full Text Available The impact of a potential future fleet of supersonic aircraft on contrail coverage and contrail radiative forcing is investigated by means of simulations with the general circulation model ECHAM4.L39(DLR including a contrail parameterization. The model simulations consider air traffic inventories of a subsonic fleet and of a combined fleet of sub- and supersonic aircraft for the years 2025 and 2050, respectively. In case of the combined fleet, part of the subsonic fleet is replaced by supersonic aircraft. The combined air traffic scenario reveals a reduction in contrail cover at subsonic cruise levels (10 to 12 km in the northern extratropics, especially over the North Atlantic and North Pacific. At supersonic flight levels (18 to 20 km, contrail formation is mainly restricted to tropical regions. Only in winter is the northern extratropical stratosphere above the 100 hPa level cold enough for the formation of contrails. Total contrail coverage is only marginally affected by the shift in flight altitude. The model simulations indicate a global annual mean contrail cover of 0.372% for the subsonic and 0.366% for the combined fleet in 2050. The simulated contrail radiative forcing is most closely correlated to the total contrail cover, although contrails in the tropical lower stratosphere are found to be optically thinner than contrails in the extratropical upper troposphere. The global annual mean contrail radiative forcing in 2050 (2025 amounts to 24.7 mW m−2 (9.4 mW m−2 for the subsonic fleet and 24.2 mW m−2 (9.3 mW m−2 for the combined fleet. A reduction of the supersonic cruise speed from Mach 2.0 to Mach 1.6 leads to a downward shift in contrail cover, but does not affect global mean total contrail cover and contrail radiative forcing. Hence the partial substitution of subsonic air traffic leads to a shift of contrail occurrence from mid to low latitudes, but the resulting change in

  5. Impact of biofuels on contrail warming

    Science.gov (United States)

    Caiazzo, Fabio; Agarwal, Akshat; Speth, Raymond L.; Barrett, Steven R. H.

    2017-11-01

    Contrails and contrail-cirrus may be the largest source of radiative forcing (RF) attributable to aviation. Biomass-derived alternative jet fuels are a potentially major way to mitigate the climate impacts of aviation by reducing lifecycle CO2 emissions. Given the up to 90% reduction in soot emissions from paraffinic biofuels, the potential for a significant impact on contrail RF due to the reduction in contrail-forming ice nuclei (IN) remains an open question. We simulate contrail formation and evolution to quantify RF over the United States under different emissions scenarios. Replacing conventional jet fuels with paraffinic biofuels generates two competing effects. First, the higher water emissions index results in an increase in contrail occurrence (~ +8%). On the other hand, these contrails are composed of larger diameter crystals (~ +58%) at lower number concentrations (~ -75%), reducing both contrail optical depth (~ -29%) and albedo (~ -32%). The net changes in contrail RF induced by switching to biofuels range from -4% to +18% among a range of assumed ice crystal habits (shapes). In comparison, cleaner burning engines (with no increase in water emissions index) result in changes to net contrail RF ranging between -13% and +5% depending on habit. Thus, we find that even 67% to 75% reductions in aircraft soot emissions are insufficient to substantially reduce warming from contrails, and that the use of biofuels may either increase or decrease contrail warming—contrary to previous expectations of a significant decrease in warming.

  6. A methodology for in-situ and remote sensing of microphysical and radiative properties of contrails as they evolve into cirrus

    Science.gov (United States)

    Jones, H. M.; Haywood, J.; Marenco, F.; O'Sullivan, D.; Meyer, J.; Thorpe, R.; Gallagher, M. W.; Krämer, M.; Bower, K. N.; Rädel, G.; Rap, A.; Woolley, A.; Forster, P.; Coe, H.

    2012-09-01

    Contrails and especially their evolution into cirrus-like clouds are thought to have very important effects on local and global radiation budgets, though are generally not well represented in global climate models. Lack of contrail parameterisations is due to the limited availability of in situ contrail measurements which are difficult to obtain. Here we present a methodology for successful sampling and interpretation of contrail microphysical and radiative data using both in situ and remote sensing instrumentation on board the FAAM BAe146 UK research aircraft as part of the COntrails Spreading Into Cirrus (COSIC) study. Forecast models were utilised to determine flight regions suitable for contrail formation and sampling; regions that were both free of cloud but showed a high probability of occurrence of air mass being supersaturated with respect to ice. The FAAM research aircraft, fitted with cloud microphysics probes and remote sensing instruments, formed a distinctive spiral-shaped contrail in the predicted area by flying in an orbit over the same ground position as the wind advected the contrails to the east. Parts of these contrails were sampled during the completion of four orbits, with sampled contrail regions being between 7 and 30 min old. Lidar measurements were useful for in-flight determination of the location and spatial extent of the contrails, and also to report extinction values that agreed well with those calculated from the microphysical data. A shortwave spectrometer was also able to detect the contrails, though the signal was weak due to the dispersion and evaporation of the contrails. Post-flight the UK Met Office NAME III dispersion model was successfully used as a tool for modelling the dispersion of the persistent contrail; determining its location and age, and determining when there was interference from other measured aircraft contrails or when cirrus encroached on the area later in the flight. The persistent contrails were found to

  7. A methodology for in-situ and remote sensing of microphysical and radiative properties of contrails as they evolve into cirrus

    Directory of Open Access Journals (Sweden)

    H. M. Jones

    2012-09-01

    Full Text Available Contrails and especially their evolution into cirrus-like clouds are thought to have very important effects on local and global radiation budgets, though are generally not well represented in global climate models. Lack of contrail parameterisations is due to the limited availability of in situ contrail measurements which are difficult to obtain. Here we present a methodology for successful sampling and interpretation of contrail microphysical and radiative data using both in situ and remote sensing instrumentation on board the FAAM BAe146 UK research aircraft as part of the COntrails Spreading Into Cirrus (COSIC study.

    Forecast models were utilised to determine flight regions suitable for contrail formation and sampling; regions that were both free of cloud but showed a high probability of occurrence of air mass being supersaturated with respect to ice. The FAAM research aircraft, fitted with cloud microphysics probes and remote sensing instruments, formed a distinctive spiral-shaped contrail in the predicted area by flying in an orbit over the same ground position as the wind advected the contrails to the east. Parts of these contrails were sampled during the completion of four orbits, with sampled contrail regions being between 7 and 30 min old. Lidar measurements were useful for in-flight determination of the location and spatial extent of the contrails, and also to report extinction values that agreed well with those calculated from the microphysical data. A shortwave spectrometer was also able to detect the contrails, though the signal was weak due to the dispersion and evaporation of the contrails. Post-flight the UK Met Office NAME III dispersion model was successfully used as a tool for modelling the dispersion of the persistent contrail; determining its location and age, and determining when there was interference from other measured aircraft contrails or when cirrus encroached on the area later in the flight.

    The

  8. Factors controlling contrail cirrus optical depth

    Directory of Open Access Journals (Sweden)

    B. Kärcher

    2009-08-01

    Full Text Available Aircraft contrails develop into contrail cirrus by depositional growth and sedimentation of ice particles and horizontal spreading due to wind shear. Factors controlling this development include temperature, ice supersaturation, thickness of ice-supersaturated layers, and vertical gradients in the horizontal wind field. An analytical microphysical cloud model is presented and validated that captures these processes. Many individual contrail cirrus are simulated that develop differently owing to the variability in the controlling factors, resulting in large samples of cloud properties that are statistically analyzed. Contrail cirrus development is studied over the first four hours past formation, similar to the ages of line-shaped contrails that were tracked in satellite imagery on regional scales. On these time scales, contrail cirrus optical depth and microphysical variables exhibit a marked variability, expressed in terms of broad and skewed probability distribution functions. Simulated mean optical depths at a wavelength of 0.55 μm range from 0.05-0.5 and a substantial fraction 20-50% of contrail cirrus stay subvisible (optical depth <0.02, depending on meteorological conditions.

    A detailed analysis based on an observational case study over the continental USA suggests that previous satellite measurements of line-shaped persistent contrails have missed about 89%, 50%, and 11% of contrails with optical depths 0-0.05, 0.05-0.1, and 0.1-0.2, respectively, amounting to 65% of contrail coverage of all optical depths. When comparing observations with simulations and when estimating the contrail cirrus climate impact, not only mean values but also the variability in optical depth and microphysical properties need to be considered.

  9. Measurement of Contrails Using ADS-B Data

    Directory of Open Access Journals (Sweden)

    Martin Voráček

    2016-01-01

    Full Text Available Air transport contributes to climate changes not only by greenhouse gas production but also because of production of contrails. The effect of contrails is less scientifically understood compared to greenhouse gases according to IPCC [3]. In order to be able to research the effect of contrails on the atmosphere, it is necessary to identify their realistic frequency of occurrence and to define the relationship between their occurrence and other factors. The effort to identify and monitor contrails and their dependence on the type of air traffic is the objective of SGS project.

  10. A diagnostic study of the global coverage by contrails. Pt. 1. Present day climate. Revised version

    Energy Technology Data Exchange (ETDEWEB)

    Sausen, R.; Gierens, K.; Ponater, M.; Schumann, U.

    1998-03-01

    The global distribution of the contrail formation potential and the contrail cloud coverage are estimated using meteorological analysis data for temperature and humidity (ECMWF re-analyses) and a data base on aircraft fuel consumption. Regions with humidity between ice and liquid saturation and with temperature low enough to let aircraft trigger contrail formation are identified as regions in which persistent contrails may be formed. The frequency with which a region is conditioned for such persistent contrail formation measures the contrail formation potential. The mean contrail cloud coverage is computed by multiplying this frequency with a suitable function of fuel consumption (linear or non-linear). The product is normalized such that the contrail coverage equals the observed value of 0.5% in a domain between 30 W to 30 E, 35 N to 75 N. The results show a large potential for contrail formation in the upper troposphere, in particular in the tropics but also at mid-latitudes. At northern mid-latitudes about 20% of the upper tropospheric air is conditioned to form persistent contrails. Part of this region may be covered by otherwise forming cirrus clouds. When multiplied with fuel consumption of 1992 aviation, large cover by persistent contrail clouds is computed over Europe, the North Atlantic, the continental USA, and south-east Asia. The computed contrail coverage reaches 2% over the USA, and is larger in winter than in summer. The global mean contrail coverage is about 0.11% for linear fuel dependence and the given normalization. The result is only weakly sensitive to the propulsion efficiency of aircraft, but strongly sensitive to aircraft flight altitude. (orig.)

  11. Occurrence and persistence of magnetic elements in the quiet Sun

    Science.gov (United States)

    Giannattasio, F.; Berrilli, F.; Consolini, G.; Del Moro, D.; Gošić, M.; Bellot Rubio, L.

    2018-03-01

    Context. Turbulent convection efficiently transports energy up to the solar photosphere, but its multi-scale nature and dynamic properties are still not fully understood. Several works in the literature have investigated the emergence of patterns of convective and magnetic nature in the quiet Sun at spatial and temporal scales from granular to global. Aims: To shed light on the scales of organisation at which turbulent convection operates, and its relationship with the magnetic flux therein, we studied characteristic spatial and temporal scales of magnetic features in the quiet Sun. Methods: Thanks to an unprecedented data set entirely enclosing a supergranule, occurrence and persistence analysis of magnetogram time series were used to detect spatial and long-lived temporal correlations in the quiet Sun and to investigate their nature. Results: A relation between occurrence and persistence representative for the quiet Sun was found. In particular, highly recurrent and persistent patterns were detected especially in the boundary of the supergranular cell. These are due to moving magnetic elements undergoing motion that behaves like a random walk together with longer decorrelations ( 2 h) with respect to regions inside the supergranule. In the vertices of the supegranular cell the maximum observed occurrence is not associated with the maximum persistence, suggesting that there are different dynamic regimes affecting the magnetic elements.

  12. Importance of representing optical depth variability for estimates of global line-shaped contrail radiative forcing.

    Science.gov (United States)

    Kärcher, Bernd; Burkhardt, Ulrike; Ponater, Michael; Frömming, Christine

    2010-11-09

    Estimates of the global radiative forcing by line-shaped contrails differ mainly due to the large uncertainty in contrail optical depth. Most contrails are optically thin so that their radiative forcing is roughly proportional to their optical depth and increases with contrail coverage. In recent assessments, the best estimate of mean contrail radiative forcing was significantly reduced, because global climate model simulations pointed at lower optical depth values than earlier studies. We revise these estimates by comparing the probability distribution of contrail optical depth diagnosed with a climate model with the distribution derived from a microphysical, cloud-scale model constrained by satellite observations over the United States. By assuming that the optical depth distribution from the cloud model is more realistic than that from the climate model, and by taking the difference between the observed and simulated optical depth over the United States as globally representative, we quantify uncertainties in the climate model's diagnostic contrail parameterization. Revising the climate model results accordingly increases the global mean radiative forcing estimate for line-shaped contrails by a factor of 3.3, from 3.5 mW/m(2) to 11.6 mW/m(2) for the year 1992. Furthermore, the satellite observations and the cloud model point at higher global mean optical depth of detectable contrails than often assumed in radiative transfer (off-line) studies. Therefore, we correct estimates of contrail radiative forcing from off-line studies as well. We suggest that the global net radiative forcing of line-shaped persistent contrails is in the range 8-20 mW/m(2) for the air traffic in the year 2000.

  13. Contrails and Climate Change: An Investigation of the Role of Aviation-Induced-Cloudiness on the Ireland Climate Using AATSR Imagery

    Science.gov (United States)

    Whelan, Gillian M.; Cawkwell, Fiona; Mannstein, Hermann; Minnis, Patrick

    2010-12-01

    Contrails, or 'condensation trails', produced in the wake of jet aircraft have been found to have a small but significant global net climate-warming effect [1]. When atmospheric conditions are favorable (i.e. when ambient atmospheric humidity is high and temperature is below a threshold value of typically less than -40oC), contrails can persist for several hours, grow to become several kilometers long and can also trigger additional cirrus- cloud formation as they spread - which can further impact climate! Due to Ireland's proximity to the North Atlantic Flight Corridor, large volumes of high-altitude overflights cross Ireland daily. Contrails are essentially artificial-linear-ice-clouds at a lower temperature than the surrounding atmosphere and so are visible in 1 Km satellite imagery at the 11 and 12 μm wavelengths; but are better detected in the temperature difference image between these two thermal channels. An automated Contrail Detection Algorithm (CDA) is applied to AATSR thermal imagery over Ireland, and the percentage contrail-coverage of each scene determined. Preliminary results, based on 2008 morning and evening AATSR overpasses show a similar annual average contrail-coverage when present of 0.25% and 0.19% respectively, even though air-traffic density is typically several times higher during the morning overpasses. Cases of excessive contrail-coverage, of up to 2.06% have been observed in combination with extensive cirrus-coverage over Ireland. Results from meteorological data indicate more highly favorable atmospheric conditions for contrail formation and persistence in 00h00 and 06h00 radiosonde ascents; which corresponds to a night-time peak in high-altitude flights over Ireland. Furthermore, exceptionally thick contrail-susceptible-atmospheric layers are found in conjunction with cases of excessive satellite-derived- contrail-coverage.

  14. Occurrence, fate, and persistence of gemfibrozil in water and soil.

    Science.gov (United States)

    Fang, Yu; Karnjanapiboonwong, Adcharee; Chase, Darcy A; Wang, Jiafan; Morse, Audra N; Anderson, Todd A

    2012-03-01

    Pharmaceuticals and personal care products (PPCPs) have emerged as a group of potential environmental contaminants of concern. The occurrence of gemfibrozil, a lipid-regulating drug, was studied in the influent and effluent at a wastewater treatment plant (WWTP) and groundwater below a land application site receiving treated effluent from the WWTP. In addition, the sorption of gemfibrozil in two loam soils and sand was assessed, and biological degradation rates in two soil types under aerobic conditions were also determined. Results showed that concentrations of gemfibrozil in wastewater influent, effluent, and groundwater were in the range of 3.47 to 63.8 µg/L, 0.08 to 19.4 µg/L, and undetectable to 6.86 µg/L, respectively. Data also indicated that gemfibrozil in the wastewater could reach groundwater following land application of the treated effluent. Soil-water distribution coefficients for gemfibrozil, determined by the batch equilibrium method, varied with organic carbon content in the soils. The sorption capacity was silt loam > sandy loam > sand. Under aerobic conditions, dissipation half-lives for gemfibrozil in sandy loam and silt loam soils were 17.8 and 20.6 days, respectively; 25.4 and 11.3% of gemfibrozil was lost through biodegradation from the two soils over 14 days. Copyright © 2011 SETAC.

  15. Large-eddy simulation of contrails

    Energy Technology Data Exchange (ETDEWEB)

    Chlond, A [Max-Planck-Inst. fuer Meteorologie, Hamburg (Germany)

    1998-12-31

    A large eddy simulation (LES) model has been used to investigate the role of various external parameters and physical processes in the life-cycle of contrails. The model is applied to conditions that are typical for those under which contrails could be observed, i.e. in an atmosphere which is supersaturated with respect to ice and at a temperature of approximately 230 K or colder. The sensitivity runs indicate that the contrail evolution is controlled primarily by humidity, temperature and static stability of the ambient air and secondarily by the baroclinicity of the atmosphere. Moreover, it turns out that the initial ice particle concentration and radiative processes are of minor importance in the evolution of contrails at least during the 30 minutes simulation period. (author) 9 refs.

  16. Large-eddy simulation of contrails

    Energy Technology Data Exchange (ETDEWEB)

    Chlond, A. [Max-Planck-Inst. fuer Meteorologie, Hamburg (Germany)

    1997-12-31

    A large eddy simulation (LES) model has been used to investigate the role of various external parameters and physical processes in the life-cycle of contrails. The model is applied to conditions that are typical for those under which contrails could be observed, i.e. in an atmosphere which is supersaturated with respect to ice and at a temperature of approximately 230 K or colder. The sensitivity runs indicate that the contrail evolution is controlled primarily by humidity, temperature and static stability of the ambient air and secondarily by the baroclinicity of the atmosphere. Moreover, it turns out that the initial ice particle concentration and radiative processes are of minor importance in the evolution of contrails at least during the 30 minutes simulation period. (author) 9 refs.

  17. A numerical simulation of a contrail

    Energy Technology Data Exchange (ETDEWEB)

    Levkov, L.; Boin, M.; Meinert, D. [GKSS-Forschungszentrum Geesthacht GmbH, Geesthacht (Germany)

    1997-12-31

    The formation of a contrail from an aircraft flying near the tropopause is simulated using a three-dimensional mesoscale atmospheric model including a very complex scheme of parameterized cloud microphysical processes. The model predicted ice concentrations are in very good agreement with data measured during the International Cirrus Experiment (ICE), 1989. Sensitivity simulations were run to determine humidity forcing on the life time of contrails. (author) 4 refs.

  18. A numerical simulation of a contrail

    Energy Technology Data Exchange (ETDEWEB)

    Levkov, L; Boin, M; Meinert, D [GKSS-Forschungszentrum Geesthacht GmbH, Geesthacht (Germany)

    1998-12-31

    The formation of a contrail from an aircraft flying near the tropopause is simulated using a three-dimensional mesoscale atmospheric model including a very complex scheme of parameterized cloud microphysical processes. The model predicted ice concentrations are in very good agreement with data measured during the International Cirrus Experiment (ICE), 1989. Sensitivity simulations were run to determine humidity forcing on the life time of contrails. (author) 4 refs.

  19. Occurrence and predictors of persistent impaired glucose tolerance after acute ischemic stroke or transient ischemic attack

    OpenAIRE

    Fonville, Susanne; Hertog, Heleen; Zandbergen, Adrienne; Koudstaal, Peter Jan; Lingsma, Hester

    2014-01-01

    textabstractBackground Impaired glucose tolerance is often present in patients with a transient ischemic attack (TIA) or ischemic stroke and doubles the risk of recurrent stroke. This impaired glucose tolerance can be transient, reflecting an acute stress response, or persistent, representing undiagnosed impaired glucose metabolism possibly requiring treatment. We aimed to assess the occurrence of persistent impaired glucose tolerance after a stroke or TIA and to develop a prediction model to...

  20. Remote sensing of contrails and aircraft altered cirrus clouds

    Energy Technology Data Exchange (ETDEWEB)

    Palikonda, R.; Nguyen, L.; Garber, D.P.; Smith, W.L. Jr [Analytical Services and Materials, Inc., Hampton, VA (United States); Minnis, P.; Young, D.F. [National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center

    1997-12-31

    Analyses of satellite imagery are used to show that contrails can develop into fully extended cirrus cloud systems. Contrails can be advective on great distances, but would appear to observers as natural cirrus clouds. The conversion of simple contrails into cirrus may help explain the apparent increase of cloudiness over populated areas since the beginning of commercial jet air travel. Statistics describing the typical growth, advection, and lifetime of contrail cirrus is needed to evaluate their effects on climate. (author) 4 refs.

  1. Remote sensing of contrails and aircraft altered cirrus clouds

    Energy Technology Data Exchange (ETDEWEB)

    Palikonda, R; Nguyen, L; Garber, D P; Smith, Jr, W L [Analytical Services and Materials, Inc., Hampton, VA (United States); Minnis, P; Young, D F [National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center

    1998-12-31

    Analyses of satellite imagery are used to show that contrails can develop into fully extended cirrus cloud systems. Contrails can be advective on great distances, but would appear to observers as natural cirrus clouds. The conversion of simple contrails into cirrus may help explain the apparent increase of cloudiness over populated areas since the beginning of commercial jet air travel. Statistics describing the typical growth, advection, and lifetime of contrail cirrus is needed to evaluate their effects on climate. (author) 4 refs.

  2. Spatial and optical parameters of contrails in the vortex and dispersion regime determined by means of a ground-based scanning lidar

    Energy Technology Data Exchange (ETDEWEB)

    Freudenthaler, V; Homburg, F; Jaeger, H [Fraunhofer-Inst. fuer Atmosphaerische Umweltforschung (IFU), Garmisch-Partenkirchen (Germany)

    1998-12-31

    The spatial growth of individual condensation trails (contrails) of commercial aircrafts in the time range from 15 s to 60 min behind the aircraft is investigated by means of a ground-based scanning backscatter lidar. The growth in width is mainly governed by wind shear and varies between 18 m/min and 140 m/min. The growth of the cross-section varies between 3500 m{sup 2}/min and 25000 m{sup 2}/min. These values are in agreement with results of model calculations and former field measurements. The vertical growth is often limited by boundaries of the humid layer at flight level, but values up to 18 m/min were observed. Optical parameters like depolarization, optical depth and lidar ratio, i.e. the extinction-to-backscatter ratio, have been retrieved from the measurements at a wavelength of 532 nm. The linear depolarization rises from values as low as 0.06 for a young contrail (10 s old) to values around 0.5, typical for aged contrails. The latter indicates the transition from non-crystalline to crystalline particles in persistent contrails within a few minutes. The scatter of depolarization values measured in individual contrails is narrow, independent of the contrails age, and suggests a rather uniform growth of the particles inside a contrail. (author) 18 refs.

  3. Spatial and optical parameters of contrails in the vortex and dispersion regime determined by means of a ground-based scanning lidar

    Energy Technology Data Exchange (ETDEWEB)

    Freudenthaler, V.; Homburg, F.; Jaeger, H. [Fraunhofer-Inst. fuer Atmosphaerische Umweltforschung (IFU), Garmisch-Partenkirchen (Germany)

    1997-12-31

    The spatial growth of individual condensation trails (contrails) of commercial aircrafts in the time range from 15 s to 60 min behind the aircraft is investigated by means of a ground-based scanning backscatter lidar. The growth in width is mainly governed by wind shear and varies between 18 m/min and 140 m/min. The growth of the cross-section varies between 3500 m{sup 2}/min and 25000 m{sup 2}/min. These values are in agreement with results of model calculations and former field measurements. The vertical growth is often limited by boundaries of the humid layer at flight level, but values up to 18 m/min were observed. Optical parameters like depolarization, optical depth and lidar ratio, i.e. the extinction-to-backscatter ratio, have been retrieved from the measurements at a wavelength of 532 nm. The linear depolarization rises from values as low as 0.06 for a young contrail (10 s old) to values around 0.5, typical for aged contrails. The latter indicates the transition from non-crystalline to crystalline particles in persistent contrails within a few minutes. The scatter of depolarization values measured in individual contrails is narrow, independent of the contrails age, and suggests a rather uniform growth of the particles inside a contrail. (author) 18 refs.

  4. Microphysical properties of contrails and natural cirrus clouds

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, B; Wendling, P [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany)

    1998-12-31

    The radiative properties of a condensation trail (contrail) are determined by its microphysical properties. Therefore an understanding of the concentration, size distribution, and shapes of the particles is necessary for an estimation of the climatic impact of contrails. In-situ particle measurements by use of an ice replicator are presented for several contrail and cirrus events. Contrail particles aged about 2 minutes show shapes which are nearly spherical. Typical sizes are 5 to 10 {mu}m. Concentration values reach up to the order of 1000 cm{sup -3}. Aged contrail size distributions are within the variability of those found in natural cirrus clouds. (author) 2 refs.

  5. Parametrization of contrails in a comprehensive climate model

    Energy Technology Data Exchange (ETDEWEB)

    Ponater, M; Brinkop, S; Sausen, R; Schumann, U [Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1998-12-31

    A contrail parametrization scheme for a general circulation model (GCM) is presented. Guidelines for its development were that it should be based on the thermodynamic theory of contrail formation and that it should be consistent with the cloud parametrization scheme of the GCM. Results of a six-year test integration indicate reasonable results concerning the spatial and temporal development of both contrail coverage and contrail optical properties. Hence, the scheme forms a promising basis for the quantitative estimation of the contrail climatic impact. (author) 9 refs.

  6. Parametrization of contrails in a comprehensive climate model

    Energy Technology Data Exchange (ETDEWEB)

    Ponater, M.; Brinkop, S.; Sausen, R.; Schumann, U. [Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    A contrail parametrization scheme for a general circulation model (GCM) is presented. Guidelines for its development were that it should be based on the thermodynamic theory of contrail formation and that it should be consistent with the cloud parametrization scheme of the GCM. Results of a six-year test integration indicate reasonable results concerning the spatial and temporal development of both contrail coverage and contrail optical properties. Hence, the scheme forms a promising basis for the quantitative estimation of the contrail climatic impact. (author) 9 refs.

  7. Microphysical properties of contrails and natural cirrus clouds

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, B.; Wendling, P. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany)

    1997-12-31

    The radiative properties of a condensation trail (contrail) are determined by its microphysical properties. Therefore an understanding of the concentration, size distribution, and shapes of the particles is necessary for an estimation of the climatic impact of contrails. In-situ particle measurements by use of an ice replicator are presented for several contrail and cirrus events. Contrail particles aged about 2 minutes show shapes which are nearly spherical. Typical sizes are 5 to 10 {mu}m. Concentration values reach up to the order of 1000 cm{sup -3}. Aged contrail size distributions are within the variability of those found in natural cirrus clouds. (author) 2 refs.

  8. A Linear Programming Approach to the Development of Contrail Reduction Strategies Satisfying Operationally Feasible Constraints

    Science.gov (United States)

    Wei, Peng; Sridhar, Banavar; Chen, Neil Yi-Nan; Sun, Dengfent

    2012-01-01

    A class of strategies has been proposed to reduce contrail formation in the United States airspace. A 3D grid based on weather data and the cruising altitude level of aircraft is adjusted to avoid the persistent contrail potential area with the consideration to fuel-efficiency. In this paper, the authors introduce a contrail avoidance strategy on 3D grid by considering additional operationally feasible constraints from an air traffic controller's aspect. First, shifting too many aircraft to the same cruising level will make the miles-in-trail at this level smaller than the safety separation threshold. Furthermore, the high density of aircraft at one cruising level may exceed the workload for the traffic controller. Therefore, in our new model we restrict the number of total aircraft at each level. Second, the aircraft count variation for successive intervals cannot be too drastic since the workload to manage climbing/descending aircraft is much larger than managing cruising aircraft. The contrail reduction is formulated as an integer-programming problem and the problem is shown to have the property of total unimodularity. Solving the corresponding relaxed linear programming with the simplex method provides an optimal and integral solution to the problem. Simulation results are provided to illustrate the methodology.

  9. Debris Flow Occurrence and Sediment Persistence, Upper Colorado River Valley, CO.

    Science.gov (United States)

    Grimsley, K J; Rathburn, S L; Friedman, J M; Mangano, J F

    2016-07-01

    Debris flow magnitudes and frequencies are compared across the Upper Colorado River valley to assess influences on debris flow occurrence and to evaluate valley geometry effects on sediment persistence. Dendrochronology, field mapping, and aerial photographic analysis are used to evaluate whether a 19th century earthen, water-conveyance ditch has altered the regime of debris flow occurrence in the Colorado River headwaters. Identifying any shifts in disturbance processes or changes in magnitudes and frequencies of occurrence is fundamental to establishing the historical range of variability (HRV) at the site. We found no substantial difference in frequency of debris flows cataloged at eleven sites of deposition between the east (8) and west (11) sides of the Colorado River valley over the last century, but four of the five largest debris flows originated on the west side of the valley in association with the earthen ditch, while the fifth is on a steep hillslope of hydrothermally altered rock on the east side. These results suggest that the ditch has altered the regime of debris flow activity in the Colorado River headwaters as compared to HRV by increasing the frequency of debris flows large enough to reach the Colorado River valley. Valley confinement is a dominant control on response to debris flows, influencing volumes of aggradation and persistence of debris flow deposits. Large, frequent debris flows, exceeding HRV, create persistent effects due to valley geometry and geomorphic setting conducive to sediment storage that are easily delineated by valley confinement ratios which are useful to land managers.

  10. Contrail observations from space using NOAA-AVHRR data

    Energy Technology Data Exchange (ETDEWEB)

    Mannstein, H. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    The infrared channels of the Advanced Very High Resolution Radiometer (AVHRR) onboard of the weather satellites of the NOAA series allow the detection of contrails. An automated detection scheme is described and tested against computer aided visual classifications by two experts. The algorithm seems to identify contrails within the satellite data with a skill comparable to the human observers. Clusters of contrails within the satellite images are connected to outline regions where the atmospheric properties are favourable for the existence of observable contrails. Air traffic data shows that, over Middle Europe at least, in the main flight levels most of these regions should be marked by detectable contrails. The mean areal coverage of these regions is estimated to be in the range of 10% to 20%, the cloud coverage by detected contrails was 0.9% in 60 AVHRR scenes covering Central Europe. (author) 3 refs.

  11. A simple framework for assessing the trade-off between the climate impact of aviation carbon dioxide emissions and contrails for a single flight

    International Nuclear Information System (INIS)

    A Irvine, E; J Hoskins, B; P Shine, K

    2014-01-01

    Persistent contrails are an important climate impact of aviation which could potentially be reduced by re-routing aircraft to avoid contrailing; however this generally increases both the flight length and its corresponding CO 2 emissions. Here, we provide a simple framework to assess the trade-off between the climate impact of CO 2 emissions and contrails for a single flight, in terms of the absolute global warming potential and absolute global temperature potential metrics for time horizons of 20, 50 and 100 years. We use the framework to illustrate the maximum extra distance (with no altitude changes) that can be added to a flight and still reduce its overall climate impact. Small aircraft can fly up to four times further to avoid contrailing than large aircraft. The results have a strong dependence on the applied metric and time horizon. Applying a conservative estimate of the uncertainty in the contrail radiative forcing and climate efficacy leads to a factor of 20 difference in the maximum extra distance that could be flown to avoid a contrail. The impact of re-routing on other climatically-important aviation emissions could also be considered in this framework. (letters)

  12. Detection of jet contrails from satellite images

    Science.gov (United States)

    Meinert, Dieter

    1994-02-01

    In order to investigate the influence of modern technology on the world climate it is important to have automatic detection methods for man-induced parameters. In this case the influence of jet contrails on the greenhouse effect shall be investigated by means of images from polar orbiting satellites. Current methods of line recognition and amplification cannot distinguish between contrails and rather sharp edges of natural cirrus or noise. They still rely on human control. Through the combination of different methods from cloud physics, image comparison, pattern recognition, and artificial intelligence we try to overcome this handicap. Here we will present the basic methods applied to each image frame, and list preliminary results derived this way.

  13. Linking occurrence and fitness to persistence: Habitat-based approach for endangered Greater Sage-Grouse

    Science.gov (United States)

    Aldridge, Cameron L.; Boyce, Mark S.

    2007-01-01

    Detailed empirical models predicting both species occurrence and fitness across a landscape are necessary to understand processes related to population persistence. Failure to consider both occurrence and fitness may result in incorrect assessments of habitat importance leading to inappropriate management strategies. We took a two-stage approach to identifying critical nesting and brood-rearing habitat for the endangered Greater Sage-Grouse (Centrocercus urophasianus) in Alberta at a landscape scale. First, we used logistic regression to develop spatial models predicting the relative probability of use (occurrence) for Sage-Grouse nests and broods. Secondly, we used Cox proportional hazards survival models to identify the most risky habitats across the landscape. We combined these two approaches to identify Sage-Grouse habitats that pose minimal risk of failure (source habitats) and attractive sink habitats that pose increased risk (ecological traps). Our models showed that Sage-Grouse select for heterogeneous patches of moderate sagebrush cover (quadratic relationship) and avoid anthropogenic edge habitat for nesting. Nests were more successful in heterogeneous habitats, but nest success was independent of anthropogenic features. Similarly, broods selected heterogeneous high-productivity habitats with sagebrush while avoiding human developments, cultivated cropland, and high densities of oil wells. Chick mortalities tended to occur in proximity to oil and gas developments and along riparian habitats. For nests and broods, respectively, approximately 10% and 5% of the study area was considered source habitat, whereas 19% and 15% of habitat was attractive sink habitat. Limited source habitats appear to be the main reason for poor nest success (39%) and low chick survival (12%). Our habitat models identify areas of protection priority and areas that require immediate management attention to enhance recruitment to secure the viability of this population. This novel

  14. On the climatic impact of contrails

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, B; Meerkoetter, R; Wissinger, B; Wendling, P [Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1998-12-31

    The impact of contrail induced cirrus clouds on regional climate is estimated for atmospheric conditions of Southern Germany that are typical for the months of July and October. This is done by the use of a regionalized one-dimensional radiative convective model (RCM). The influence of an increased ice cloud cover is studied by comparing RCM results using averaged climatological values of cloudiness with those of a case with modified cloudiness. It turns out that a 10% increase in ice cloud cover leads to a surface temperature increase of 1.4 K and 1.2 K for the months of July and October, respectively. (author) 14 refs.

  15. On the climatic impact of contrails

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, B.; Meerkoetter, R.; Wissinger, B.; Wendling, P. [Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    The impact of contrail induced cirrus clouds on regional climate is estimated for atmospheric conditions of Southern Germany that are typical for the months of July and October. This is done by the use of a regionalized one-dimensional radiative convective model (RCM). The influence of an increased ice cloud cover is studied by comparing RCM results using averaged climatological values of cloudiness with those of a case with modified cloudiness. It turns out that a 10% increase in ice cloud cover leads to a surface temperature increase of 1.4 K and 1.2 K for the months of July and October, respectively. (author) 14 refs.

  16. Airborne persistent toxic substances (PTSs) in China: occurrence and its implication associated with air pollution.

    Science.gov (United States)

    Wang, Pu; Zhang, Qinghua; Li, Yingming; Matsiko, Julius; Zhang, Ya; Jiang, Guibin

    2017-08-16

    In recent years, China suffered from extensive air pollution due to the rapidly expanding economic and industrial developments. Its severe impact on human health has raised great concern currently. Persistent toxic substances (PTSs), a large group of environmental pollutants, have also received much attention due to their adverse effects on both the ecosystem and public health. However, limited studies have been conducted to reveal the airborne PTSs associated with air pollution at the national scale in China. In this review, we summarized the occurrence and variation of airborne PTSs in China, especially in megacities. These PTSs included polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), halogenated flame retardants (HFRs), perfluorinated compounds (PFCs), organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals. The implication of their occurrence associated with air pollution was discussed, and the emission source of these chemicals was concluded. Most reviewed studies have been conducted in east and south China with more developed economy and industry. Severe contamination of airborne PTSs generally occurred in megacities with large populations, such as Guangzhou, Shanghai and Beijing. However, the summarized results suggested that industrial production and product consumption are the major sources of most PTSs in the urban environment, while unintentional emission during anthropogenic activities is an important contributor to airborne PTSs. It is important that fine particles serve as a major carrier of most airborne PTSs, which facilitates the long-range atmospheric transport (LRAT) of PTSs, and therefore, increases the exposure risk of the human body to these pollutants. This implied that not only the concentration and chemical composition of fine particles but also the absorbed PTSs are of particular concern when air pollution occurs.

  17. Occurrence and persistence of antibiotic resistance genes in river biofilms after wastewater inputs in small rivers

    International Nuclear Information System (INIS)

    Proia, Lorenzo; Schiller, Daniel von; Sànchez-Melsió, Alexandre; Sabater, Sergi; Borrego, Carles M.; Rodríguez-Mozaz, Sara; Balcázar, José Luis

    2016-01-01

    pharmaceutical compounds. - Highlights: • We evaluated the effect of WWTP effluents on small rivers. • We investigated the occurrence of antibiotic resistance genes (ARGs) in biofilms. • WWTP effluents deeply modified the characteristics of the receiving streams. • WWTP effluents favoured the spread and persistence of ARGs in biofilms. • The increase of ARGs in biofilms was noticeable far downstream of the WWTP discharge. - The study of biofilms in rivers revealed that small wastewater treatment plants can be a relevant source of antibiotic resistance genes to benthic communities of freshwater ecosystems.

  18. Aircraft clouds: from chemtrail pseudoscience to the science of contrails

    OpenAIRE

    Mazón Bueso, Jordi; Costa, Marcel; Pino González, David

    2018-01-01

    The most frequent statements and arguments found in pseudoscience websites and forums supporting the existence of so-called aircraft chemtrails can be refuted with a scientific explanation of the processes resulting in the formation of condensation or deposition trails, known as contrails. Thus, the hypothesis that chemtrails exist is disproven by the scientific literature that shows that they are the exact same entity as contrails: They are hydrological phenomena which result from a physical...

  19. Occurrence of Legacy and New Persistent Organic Pollutants in Avian Tissues from King George Island, Antarctica.

    Science.gov (United States)

    Kim, Jun-Tae; Son, Min-Hui; Kang, Jung-Ho; Kim, Jeong-Hoon; Jung, Jin-Woo; Chang, Yoon-Seok

    2015-11-17

    Legacy and new persistent organic pollutants (POPs), including polychlorinated naphthalenes (PCNs), Dechlorane Plus (DPs) and related compounds (Dechloranes), hexabromocyclododecanes (HBCDs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs), were analyzed in avian tissue samples from King George Island, Antarctica. The avian species consisted of the Gentoo penguin (Pygoscelis papua), the Adelie penguin (Pygoscelis adeliae), the South polar skua (Stercorarius maccormicki), and the Brown skua (Stercorarius antarcticus). HBCDs were detected in all samples and ranged from 1.67-713 pg/g-lipid. In the penguin samples, the concentrations of PCNs ranged from 0.69-2.07 ng/g-lipid, whereas those in the skua samples ranged from 7.41-175 ng/g-lipid. The levels of Dechloranes ranged from 0.60-1.30 ng/g-lipid in the penguin samples and from 6.57-47.4 ng/g-lipid in the skua samples. The concentrations and congener distributions of OCPs and PCBs were similar to the results of previous reports. The three new POPs were detected in all samples, and this study was one of the first reports on the occurrence of these pollutants in the Antarctic biota. Because Antarctica is one of the most pristine places on Earth, the detection of new POPs in the Antarctic birds, especially penguins, is direct evidence of the long-range transport of pollutants. Furthermore, the concentration ratios of the penguin to the skua samples (BMFs-p) were greater than 1 in most legacy and new POPs, and the BMFs-p values of the new POPs were comparable to those of some OCPs, suggesting a possibility of biomagnification. Despite the small sample size, the results of this study identified POP contamination of the Antarctic avian species and long-range transport and biomagnification of HBCDs, Dechloranes, and PCNs.

  20. Experiments on contrail formation from fuels with different sulfur content

    Energy Technology Data Exchange (ETDEWEB)

    Busen, R; Kuhn, M; Petzold, A; Schroeder, F; Schumann, U [Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany); Baumgardner, D [National Center for Atmospheric Research, Boulder, CO (United States); Borrmann, S [Mainz Univ. (Germany); Hagen, D; Whitefield, Ph [Missouri Univ., Rolla, MO (United States). Bureau of Mines; Stroem, J [Stockholm Univ. (Sweden)

    1998-12-31

    A series of both flight tests and ground experiments has been performed to evaluate the role of the sulfur contained in kerosene in condensation trail (contrail) formation processes. The results of the first experiments are compiled briefly. The last SULFUR 4 experiment dealing with the influence of the fuel sulfur content and different appertaining conditions is described in detail. Different sulfur mass fractions lead to different particle size spectra. The number of ice particles in the contrail increases by about a factor of 2 for 3000 ppm instead of 6 ppm sulfur fuel content. (author) 10 refs.

  1. Experiments on contrail formation from fuels with different sulfur content

    Energy Technology Data Exchange (ETDEWEB)

    Busen, R.; Kuhn, M.; Petzold, A.; Schroeder, F.; Schumann, U. [Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany); Baumgardner, D. [National Center for Atmospheric Research, Boulder, CO (United States); Borrmann, S. [Mainz Univ. (Germany); Hagen, D.; Whitefield, Ph. [Missouri Univ., Rolla, MO (United States). Bureau of Mines; Stroem, J. [Stockholm Univ. (Sweden)

    1997-12-31

    A series of both flight tests and ground experiments has been performed to evaluate the role of the sulfur contained in kerosene in condensation trail (contrail) formation processes. The results of the first experiments are compiled briefly. The last SULFUR 4 experiment dealing with the influence of the fuel sulfur content and different appertaining conditions is described in detail. Different sulfur mass fractions lead to different particle size spectra. The number of ice particles in the contrail increases by about a factor of 2 for 3000 ppm instead of 6 ppm sulfur fuel content. (author) 10 refs.

  2. Occurrence and predictors of persistent impaired glucose tolerance after acute ischemic stroke or transient ischemic attack

    NARCIS (Netherlands)

    S. Fonville (Susanne); H.M. den Hertog (Heleen); A.A.M. Zandbergen (Adrienne); P.J. Koudstaal (Peter Jan); H.F. Lingsma (Hester)

    2014-01-01

    textabstractBackground Impaired glucose tolerance is often present in patients with a transient ischemic attack (TIA) or ischemic stroke and doubles the risk of recurrent stroke. This impaired glucose tolerance can be transient, reflecting an acute stress response, or persistent, representing

  3. Occurrence and persistence of freshwater turtles in Portugal: problems of scale and implications for conservation

    OpenAIRE

    Segurado, Pedro

    2007-01-01

    Correlative modelling approaches have been used as first approximations to infer the role of environmental and biotic factors underlying species occurrences. However correlative models cannot demonstrate unequivocally causal relationships. Furthermore a number of artefacts may cause some inferred relationships to be spurious. In this thes is I focus my work on these sources of uncertainty. First I demonstrate the joint effect of the kind of modelling technique and species macroecological trai...

  4. Contrails and their impact on shortwave radiation and photovoltaic power production – a regional model study

    Directory of Open Access Journals (Sweden)

    S. Gruber

    2018-05-01

    Full Text Available A high-resolution regional-scale numerical model was extended by a parameterization that allows for both the generation and the life cycle of contrails and contrail cirrus to be calculated. The life cycle of contrails and contrail cirrus is described by a two-moment cloud microphysical scheme that was extended by a separate contrail ice class for a better representation of the high concentration of small ice crystals that occur in contrails. The basic input data set contains the spatially and temporally highly resolved flight trajectories over Central Europe derived from real-time data. The parameterization provides aircraft-dependent source terms for contrail ice mass and number. A case study was performed to investigate the influence of contrails and contrail cirrus on the shortwave radiative fluxes at the earth's surface. Accounting for contrails produced by aircraft enabled the model to simulate high clouds that were otherwise missing on this day. The effect of these extra clouds was to reduce the incoming shortwave radiation at the surface as well as the production of photovoltaic power by up to 10 %.

  5. Investigating Spatial Patterns of Persistent Scatterer Interferometry Point Targets and Landslide Occurrences in the Arno River Basin

    Directory of Open Access Journals (Sweden)

    Ping Lu

    2014-07-01

    Full Text Available Persistent Scatterer Interferometry (PSI has been widely used for landslide studies in recent years. This paper investigated the spatial patterns of PSI point targets and landslide occurrences in the Arno River basin in Central Italy. The main purpose is to analyze whether spatial patterns of Persistent Scatterers (PS can be recognized as indicators of landslide occurrences throughout the whole basin. The bivariate K-function was employed to assess spatial relationships between PS and landslides. The PSI point targets were acquired from almost 4 years (from March 2003 to January 2007 of RADARSAT-1 images. The landslide inventory was collected from 15 years (from 1992–2007 of surveying and mapping data, mainly including remote sensing data, topographic maps and field investigations. The proposed approach is able to assess spatial patterns between a variety of PS and landslides, in particular, to understand if PSI point targets are spatially clustered (spatial attraction or randomly distributed (spatial independency on various types of landslides across the basin. Additionally, the degree and scale distances of PS clustering on a variety of landslides can be characterized. The results rejected the null hypothesis that PSI point targets appear to cluster similarly on four types of landslides (slides, flows, falls and creeps in the Arno River basin. Significant influence of PS velocities and acquisition orbits can be noticed on detecting landslides with different states of activities. Despite that the assessment may be influenced by the quality of landslide inventory and Synthetic Aperture Radar (SAR images, the proposed approach is expected to provide guidelines for studies trying to detect and investigate landslide occurrences at a regional scale through spatial statistical analysis of PS, for which an advanced understanding of the impact of scale distances on landslide clustering is fundamentally needed.

  6. Occurrence and persistence of fungicides in bed sediments and suspended solids from three targeted use areas in the United States.

    Science.gov (United States)

    Smalling, Kelly L; Reilly, Timothy J; Sandstrom, Mark W; Kuivila, Kathryn M

    2013-03-01

    To document the environmental occurrence and persistence of fungicides, a robust and sensitive analytical method was used to measure 34 fungicides and an additional 57 current-use pesticides in bed sediments and suspended solids collected from areas of intense fungicide use within three geographic areas across the United States. Sampling sites were selected near or within agricultural research farms using prophylactic fungicides at rates and types typical of their geographic location. At least two fungicides were detected in 55% of the bed and 83% of the suspended solid samples and were detected in conjunction with herbicides and insecticides. Six fungicides were detected in all samples including pyraclostrobin (75%), boscalid (53%), chlorothalonil (41%) and zoxamide (22%). Pyraclostrobin, a strobilurin fungicide, used frequently in the United States on a variety of crops, was detected more frequently than p,p'-DDE, the primary degradate of p,p'-DDT, which is typically one of the most frequently occurring pesticides in sediments collected within highly agricultural areas. Maximum fungicide concentrations in bed sediments and suspended solids were 198 and 56.7 μg/kg dry weight, respectively. There is limited information on the occurrence, fate, and persistence of many fungicides in sediment and the environmental impacts are largely unknown. The results of this study indicate the importance of documenting the persistence of fungicides in the environment and the need for a better understanding of off-site transport mechanisms, particularly in areas where crops are grown that require frequent treatments to prevent fungal diseases. Published by Elsevier B.V.

  7. Variability of the contrail radiative forcing due to crystal shape

    Science.gov (United States)

    Markowicz, K. M.; Witek, M. L.

    2011-12-01

    The aim of this study is to examine the influence of particles' shape and particles' optical properties on the contrail radiative forcing. Contrail optical properties in the shortwave and longwave range are derived using a ray-tracing geometric method and the discrete dipole approximation method, respectively. Both methods present good correspondence of the single scattering albedo and the asymmetry parameter in a transition range (3-7μm). We compare optical properties defined following simple 10 crystals habits randomly oriented: hexagonal plates, hexagonal columns with different aspect ratio, and spherical. There are substantial differences in single scattering properties between ten crystal models investigated here (e.g. hexagonal columns and plates with different aspect ratios, spherical particles). The single scattering albedo and the asymmetry parameter both vary up to 0.1 between various crystal shapes. Radiative forcing calculations were performed using a model which includes an interface between the state-of-the-art radiative transfer model Fu-Liou and databases containing optical properties of the atmosphere and surface reflectance and emissivity. This interface allows to determine radiative fluxes in the atmosphere and to estimate the contrail radiative forcing for clear- and all-sky (including natural clouds) conditions for various crystal shapes. The Fu-Liou code is fast and therefore it is suitable for computing radiative forcing on a global scale. At the same time it has sufficiently good accuracy for such global applications. A noticeable weakness of the Fu-Liou code is that it does not take into account the 3D radiative effects, e.g. cloud shading and horizontal. Radiative transfer model calculations were performed at horizontal resolution of 5x5 degree and time resolution of 20 min during day and 3 h during night. In order to calculate a geographic distribution of the global and annual mean contrail radiative forcing, the contrail cover must be

  8. Extrapolation of contrail investigations by LIDAR to larger scale measurements. Analysis and calibration of CCD camera and satellite images

    Energy Technology Data Exchange (ETDEWEB)

    Sussmann, R.; Homburg, F.; Freudenthaler, V.; Jaeger, H. [Frauenhofer Inst. fuer Atmosphaerische Umweltforschung, Garmisch-Partenkirchen (Germany)

    1997-12-31

    The CCD image of a persistent contrail and the coincident LIDAR measurement are presented. To extrapolate the LIDAR derived optical thickness to the video field of view an anisotropy correction and calibration has to be performed. Observed bright halo components result from highly regular oriented hexagonal crystals with sizes of 200 {mu}m-2 mm. This explained by measured ambient humidities below the formation threshold of natural cirrus. Optical thickness from LIDAR shows significant discrepancies to the result from coincident NOAA-14 data. Errors result from anisotropy correction and parameterized relations between AVHRR channels and optical properties. (author) 28 refs.

  9. Towards a Model Climatology of Relative Humidity in the Upper Troposphere for Estimation of Contrail and Contrail-Induced Cirrus

    Science.gov (United States)

    Selkirk, Henry B.; Manyin, M.; Ott, L.; Oman, L.; Benson, C.; Pawson, S.; Douglass, A. R.; Stolarski, R. S.

    2011-01-01

    The formation of contrails and contrail cirrus is very sensitive to the relative humidity of the upper troposphere. To reduce uncertainty in an estimate of the radiative impact of aviation-induced cirrus, a model must therefore be able to reproduce the observed background moisture fields with reasonable and quantifiable fidelity. Here we present an upper tropospheric moisture climatology from a 26-year ensemble of simulations using the GEOS CCM. We compare this free-running model's moisture fields to those obtained from the MLS and AIRS satellite instruments, our most comprehensive observational databases for upper tropospheric water vapor. Published comparisons have shown a substantial wet bias in GEOS-5 assimilated fields with respect to MLS water vapor and ice water content. This tendency is clear as well in the GEOS CCM simulations. The GEOS-5 moist physics in the GEOS CCM uses a saturation adjustment that prevents supersaturation, which is unrealistic when compared to in situ moisture observations from MOZAIC aircraft and balloon sondes as we will show. Further, the large-scale satellite datasets also consistently underestimate super-saturation when compared to the in-situ observations. We place these results in the context of estimates of contrail and contrail cirrus frequency.

  10. Occurrence of persistent organic pollutants in marine fish from the Natuna Island, South China Sea.

    Science.gov (United States)

    Hao, Qing; Sun, Yu-Xin; Xu, Xiang-Rong; Yao, Zi-Wei; Wang, You-Shao; Zhang, Zai-Wang; Luo, Xiao-Jun; Mai, Bi-Xian

    2014-08-15

    Five marine fish species were collected from the Natuna Island, South China Sea to investigate the occurrence of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs). Concentrations of PBDEs, PCBs, and DDTs in marine fish ranged from 2.85 to 7.82, 14.3 to 48.1, and 7.99 to 40.3 ng/g lipid weight, respectively. Higher concentrations of PBDEs, PCBs, and DDTs were observed in Snakefish (Trachinocephalus myops), which might be attributed to their different feeding and living habits. PCBs were the predominant POPs in all marine fish, followed by DDTs and PBDEs. BDE 47 and PCB 153 were the predominant congener of PBDEs and PCBs, respectively. Compositional distribution of DDTs indicated the possible presence of fresh input sources around the Natuna Island. The ratios of o,p'-DDT/p,p'-DDT being less than 1 in fish samples suggested that DDT contributions from dicofol seemed considerably low. New input sources of DDT in South China Sea are worth further research. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Contrails over the U.S. and their potential impact on the radiation budget

    Energy Technology Data Exchange (ETDEWEB)

    Minnis, P [National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center; Ayers, J K; Doelling, D R [Analytical Services and Materials, Inc., Hampton, VA (United States)

    1998-12-31

    A methodology for assessing the contrail impact on the radiation budget is developed to use data characterizing the frequency, areal coverage, optical depth, particle size, and altitude of contrails with observations of cloud and surface properties. The method is tested using various scenarios over the United States to estimate contrail-induced albedo changes based on current aircraft fuel usage statistics. The technique can be used for estimating infrared effects and the impact of future fuel-use rates. (author) 11 refs.

  12. Contrails over the U.S. and their potential impact on the radiation budget

    Energy Technology Data Exchange (ETDEWEB)

    Minnis, P. [National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center; Ayers, J.K.; Doelling, D.R. [Analytical Services and Materials, Inc., Hampton, VA (United States)

    1997-12-31

    A methodology for assessing the contrail impact on the radiation budget is developed to use data characterizing the frequency, areal coverage, optical depth, particle size, and altitude of contrails with observations of cloud and surface properties. The method is tested using various scenarios over the United States to estimate contrail-induced albedo changes based on current aircraft fuel usage statistics. The technique can be used for estimating infrared effects and the impact of future fuel-use rates. (author) 11 refs.

  13. Occurrence and Biological Fate of Persistent Organic Contaminants in Yellow Sea Fish

    Directory of Open Access Journals (Sweden)

    Narayanan Kannan

    2010-01-01

    Full Text Available Persistent Organic Pollutants (POPs, namely, Polychlorinated biphenyls (PCBs, DDTs, HCHs, HCB, aldrin, endrin, dieldrin, endosulfan, heptachlors, mirex and chlordane compounds were investigated in muscle and liver tissues of Yellow Sea croakers (Collichthys niveatus and Pseudosciaena crocea from 16 stations on the off shore waters of South Korea within the Yellow Sea Large Marine Ecosystem (YSLME. The sum concentration (minimum-maximum - ng/g lipid wt. was: PCBs: non-detectable to 21; Pesticides non-detectable to 63. Among the 26 individual pesticide compounds measured in fishes, except 1,2,4,5-tetrachlorobenzene (TCBZ, all the other compounds were determined in almost in all samples. The levels in Yellow Sea croakers were similar to levels reported in the Baltic fish. The differential ratios of isomers/congeners in biota in comparison to the original commercial mixtures suggest possible metabolism by cytochrome P450 isozymes. The induction of such drug metabolizing enzymes suggests an ecotoxicological stress. Principle Component Analysis identifies ‘hot spots’ within the sampled area including the Korean off shore sewage dumpsite.

  14. Monitoring occurrence and persistence of Listeria monocytogenes in foods and food processing environments in the Republic of Ireland

    Directory of Open Access Journals (Sweden)

    Dara eLeong

    2014-08-01

    Full Text Available Although rates of listeriosis are low in comparison to other foodborne pathogenic illnesses, listeriosis poses a significant risk to human health as the invasive form can have a mortality rate as high as 30%. Food processors, especially those who produce ready-to-eat products, need to be vigilant against Listeria monocytogenes, the causative pathogen of listeriosis, and as such, the occurrence of L. monocytogenes in food and in the food processing environment needs to be carefully monitored. To examine the prevalence and patterns of contamination in food processing facilities in Ireland, 48 food processors submitted 8 samples every 2 months from March 2013 to March 2014 to be analyzed for L. monocytogenes. No positive samples were detected for 38% of the processing facilities tested. Isolates found at the remaining 62% of facilities were characterized by serotyping and Pulsed Field Gel Electrophoresis (PFGE. A general L. monocytogenes prevalence of 4.6% was seen in all samples analyzed with similar rates seen in food and environmental samples. Differences in prevalence were seen across different food processors, food sectors, sampling months etc. and PFGE analysis allowed for the examination of contamination patterns and for the identification of several persistent strains. Seven of the food processing facilities tested showed contamination with persistent strains and evidence of bacterial transfer from the processing environment to food (the same pulsotype found in both was seen in four of the food processing facilities tested.

  15. Occurrence, Persistence, and Virulence Potential of Listeria ivanovii in Foods and Food Processing Environments in the Republic of Ireland

    Science.gov (United States)

    Morgan, Ciara A.; Hill, Colin; Gahan, Cormac G. M.; Jordan, Kieran

    2015-01-01

    The aim of this study was to assess the occurrence of L. ivanovii in foods and food processing environments in Ireland, to track persistence, and to characterize the disease causing potential of the isolated strains. A total of 2,006 samples (432 food samples and 1,574 environmental swabs) were collected between March 2013 and March 2014 from 48 food business operators (FBOs) belonging to different production sectors (dairy, fish, meat, and fresh-cut vegetable). Six of the forty-eight FBOs had samples positive for L. ivanovii on at least one sampling occasion. L. ivanovii was present in fifteen samples (fourteen environmental samples and one food sample). All but one of those positive samples derived from the dairy sector, where L. ivanovii prevalence was 1.7%. Six distinguishable pulsotypes were obtained by PFGE analysis, with one pulsotype being persistent in the environment of a dairy food business. Sequence analysis of the sigB gene showed that fourteen isolates belonged to L. ivanovii subsp. londoniensis, while only one isolate was L. ivanovii subsp. ivanovii. Cell invasion assays demonstrated that the majority of L. ivanovii strains were comparable to L. monocytogenes EGDe in their ability to invade CACO-2 epithelial cells whilst four isolates had significantly higher invasion efficiencies. PMID:26543856

  16. Monitoring occurrence and persistence of Listeria monocytogenes in foods and food processing environments in the Republic of Ireland.

    Science.gov (United States)

    Leong, Dara; Alvarez-Ordóñez, Avelino; Jordan, Kieran

    2014-01-01

    Although rates of listeriosis are low in comparison to other foodborne pathogenic illness, listeriosis poses a significant risk to human health as the invasive form can have a mortality rate as high as 30%. Food processors, especially those who produce ready-to-eat (RTE) products, need to be vigilant against Listeria monocytogenes, the causative pathogen of listeriosis, and as such, the occurrence of L. monocytogenes in food and in the food processing environment needs to be carefully monitored. To examine the prevalence and patterns of contamination in food processing facilities in Ireland, 48 food processors submitted 8 samples every 2 months from March 2013 to March 2014 to be analyzed for L. monocytogenes. No positive samples were detected at 38% of the processing facilities tested. Isolates found at the remaining 62% of facilities were characterized by serotyping and Pulsed Field Gel Electrophoresis (PFGE). A general L. monocytogenes prevalence of 4.6% was seen in all samples analyzed with similar rates seen in food and environmental samples. Differences in prevalence were seen across different food processors, food sectors, sampling months etc. and PFGE analysis allowed for the examination of contamination patterns and for the identification of several persistent strains. Seven of the food processing facilities tested showed contamination with persistent strains and evidence of bacterial transfer from the processing environment to food (the same pulsotype found in both) was seen in four of the food processing facilities tested.

  17. Occurrence, Persistence, and Virulence Potential of Listeria ivanovii in Foods and Food Processing Environments in the Republic of Ireland

    Directory of Open Access Journals (Sweden)

    Avelino Alvarez-Ordóñez

    2015-01-01

    Full Text Available The aim of this study was to assess the occurrence of L. ivanovii in foods and food processing environments in Ireland, to track persistence, and to characterize the disease causing potential of the isolated strains. A total of 2,006 samples (432 food samples and 1,574 environmental swabs were collected between March 2013 and March 2014 from 48 food business operators (FBOs belonging to different production sectors (dairy, fish, meat, and fresh-cut vegetable. Six of the forty-eight FBOs had samples positive for L. ivanovii on at least one sampling occasion. L. ivanovii was present in fifteen samples (fourteen environmental samples and one food sample. All but one of those positive samples derived from the dairy sector, where L. ivanovii prevalence was 1.7%. Six distinguishable pulsotypes were obtained by PFGE analysis, with one pulsotype being persistent in the environment of a dairy food business. Sequence analysis of the sigB gene showed that fourteen isolates belonged to L. ivanovii subsp. londoniensis, while only one isolate was L. ivanovii subsp. ivanovii. Cell invasion assays demonstrated that the majority of L. ivanovii strains were comparable to L. monocytogenes EGDe in their ability to invade CACO-2 epithelial cells whilst four isolates had significantly higher invasion efficiencies.

  18. Occurrence and persistence of antifouling biocide Irgarol 1051 and its main metabolite in the coastal waters of Southern England

    International Nuclear Information System (INIS)

    Zhou, John L.

    2008-01-01

    The toxicity and persistence of antifouling booster biocides are of major concern. This study reports the occurrence of Irgarol 1051 and its degradation product M1, in coastal waters of Southern England, during 2004-2005. The highest concentrations of Irgarol 1051 were 89 ng/L in water and 45 ng/g dry weight in sediments, with an overall mean (n = 108) of 13 ng/L and 16 ng/g in water and sediments, respectively. As the degradation product of Irgarol 1051, M1 was less widespread, with the highest concentration of 30 ng/L in water and 14 ng/g in sediments, with an overall mean (n = 108) of 5 ng/L and 4 ng/g in water and sediments, respectively. Overall, the concentration of Irgarol 1051 and M1 decreased significantly during the sampling period and in comparison to earlier studies during 2000 to early 2004, indicating that control measures by restricting the use of Irgarol 1051 are effective in reducing its concentrations in coastal waters. The distribution of Irgarol 1051 between sediments and water was significantly related to sediment organic carbon content. In addition, significantly higher concentrations of Irgarol 1051 were detected in paint particles than in sediment. The rate of release of Irgarol 1051 from paint residues is very slow, with a half life of approximately 1 y. Two important findings are emerging, first the importance of organic rich sediments and paint residues as major sites of storage for Irgarol 1051, and secondly Irgarol 1051 may be classified as a persistent organic pollutant due to its long half life

  19. On the regional climatic impact of contrails: microphysical and radiative properties of contrails and natural cirrus clouds

    Directory of Open Access Journals (Sweden)

    B. Strauss

    Full Text Available The impact of contrail-induced cirrus clouds on regional climate is estimated for mean atmospheric conditions of southern Germany in the months of July and October. This is done by use of a regionalized one-dimensional radiative convective model (RCM. The influence of an increased ice cloud cover is studied by comparing RCM results representing climatological values with a modified case. In order to study the sensitivity of this effect on the radiative characteristics of the ice cloud, two types of additional ice clouds were modelled: cirrus and contrails, the latter cloud type containing a higher number of smaller and less of the larger cloud particles. Ice cloud parameters are calculated on the basis of a particle size distribution which covers the range from 2 to 2000 µm, taking into consideration recent measurements which show a remarkable amount of particles smaller than 20 µm. It turns out that a 10% increase in ice cloud cover leads to a surface temperature increase in the order of 1K, ranging from 1.1 to 1.2K in July and from 0.8 to 0.9K in October depending on the radiative characteristics of the air-traffic-induced ice clouds. Modelling the current contrail cloud cover which is near 0.5% over Europe yields a surface temperature increase in the order of 0.05K.

  20. On the regional climatic impact of contrails: microphysical and radiative properties of contrails and natural cirrus clouds

    Directory of Open Access Journals (Sweden)

    B. Strauss

    1997-11-01

    Full Text Available The impact of contrail-induced cirrus clouds on regional climate is estimated for mean atmospheric conditions of southern Germany in the months of July and October. This is done by use of a regionalized one-dimensional radiative convective model (RCM. The influence of an increased ice cloud cover is studied by comparing RCM results representing climatological values with a modified case. In order to study the sensitivity of this effect on the radiative characteristics of the ice cloud, two types of additional ice clouds were modelled: cirrus and contrails, the latter cloud type containing a higher number of smaller and less of the larger cloud particles. Ice cloud parameters are calculated on the basis of a particle size distribution which covers the range from 2 to 2000 µm, taking into consideration recent measurements which show a remarkable amount of particles smaller than 20 µm. It turns out that a 10% increase in ice cloud cover leads to a surface temperature increase in the order of 1K, ranging from 1.1 to 1.2K in July and from 0.8 to 0.9K in October depending on the radiative characteristics of the air-traffic-induced ice clouds. Modelling the current contrail cloud cover which is near 0.5% over Europe yields a surface temperature increase in the order of 0.05K.

  1. Parametric studies of contrail ice particle formation in jet regime using microphysical parcel modeling

    Directory of Open Access Journals (Sweden)

    H.-W. Wong

    2010-04-01

    Full Text Available Condensation trails (contrails formed from water vapor emissions behind aircraft engines are the most uncertain components of the aviation impacts on climate change. To gain improved knowledge of contrail and contrail-induced cirrus cloud formation, understanding of contrail ice particle formation immediately after aircraft engines is needed. Despite many efforts spent in modeling the microphysics of ice crystal formation in jet regime (with a plume age <5 s, systematic understanding of parametric effects of variables affecting contrail ice particle formation is still limited. In this work, we apply a microphysical parcel modeling approach to study contrail ice particle formation in near-field aircraft plumes up to 1000 m downstream of an aircraft engine in the soot-rich regime (soot number emission index >1×1015 (kg-fuel−1 at cruise. The effects of dilution history, ion-mediated nucleation, ambient relative humidity, fuel sulfur contents, and initial soot emissions were investigated. Our simulation results suggest that ice particles are mainly formed by water condensation on emitted soot particles. The growth of ice coated soot particles is driven by water vapor emissions in the first 1000 m and by ambient relative humidity afterwards. The presence of chemi-ions does not significantly contribute to the formation of ice particles in the soot-rich regime, and the effect of fuel sulfur contents is small over the range typical of standard jet fuels. The initial properties of soot emissions play the most critical role, and our calculations suggest that higher number concentration and smaller size of contrail particle nuclei may be able to effectively suppress the formation of contrail ice particles. Further modeling and experimental studies are needed to verify if our findings can provide a possible approach for contrail mitigation.

  2. In-situ observations of young contrails – overview and selected results from the CONCERT campaign

    Directory of Open Access Journals (Sweden)

    C. Voigt

    2010-09-01

    Full Text Available Lineshaped contrails were detected with the research aircraft Falcon during the CONCERT – CONtrail and Cirrus ExpeRimenT – campaign in October/November 2008. The Falcon was equipped with a set of instruments to measure the particle size distribution, shape, extinction and chemical composition as well as trace gas mixing ratios of sulfur dioxide (SO2, reactive nitrogen and halogen species (NO, NOy, HNO3, HONO, HCl, ozone (O3 and carbon monoxide (CO. During 12 mission flights over Europe, numerous contrails, cirrus clouds and a volcanic aerosol layer were probed at altitudes between 8.5 and 11.6 km and at temperatures above 213 K. 22 contrails from 11 different aircraft were observed near and below ice saturation. The observed NO mixing ratios, ice crystal and soot number densities are compared to a process based contrail model. On 19 November 2008 the contrail from a CRJ-2 aircraft was penetrated in 10.1 km altitude at a temperature of 221 K. The contrail had mean ice crystal number densities of 125 cm−3 with effective radii reff of 2.6 μm. The presence of particles with r>50 μm in the less than 2 min old contrail suggests that natural cirrus crystals were entrained in the contrail. Mean HONO/NO (HONO/NOy ratios of 0.037 (0.024 and the fuel sulfur conversion efficiency to H2SO4S of 2.9 % observed in the CRJ-2 contrail are in the range of previous measurements in the gaseous aircraft exhaust. On 31 October 2010 aviation NO emissions could have contributed by more than 40% to the regional scale NO levels in the mid-latitude lowest stratosphere. The CONCERT observations help to better quantify the climate impact from contrails and will be used to investigate the chemical processing of trace gases on contrails.

  3. Microphysical and optical properties of contrails and cirrus

    Energy Technology Data Exchange (ETDEWEB)

    Gayet, J F; Febvre, G [Universite Blaise Pascal, Clermont-Ferand (France). Lab. de Meteorologie Physique; Brogniez, G [Universite des Sciences et Techniques de Lille, (France). Lab. d` Optique Atmospherique; Wendling, P [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Larsen, H [National Inst. for Water and Atmospheric Research, Wellington (New Zealand)

    1998-12-31

    Aircraft contrails have significantly different properties to natural cirrus clouds. Their local and global climate impact cannot be assessed without consideration of these differences. Microphysical data were obtained from the Merlin aircraft equipped with a PMS FSSP-100 for particle spectrum measurements over the 3 {mu}m to 45 {mu}m diameter range; a PMS 2D-C for particle size spectrum and particle shape over the size range from 25 {mu}m to 800 {mu}m and a Johnson-Williams cloud liquid-water probe. Radiative measurements were obtained from a Do228 aircraft which carried the upward looking ALEX-F Lidar operating at a wavelength of 1.06 {mu}m and a Barnes PRT-5 radiometer aligned parallel to the lidar and with a 9 to 11 {mu}m spectral range. The limitation in accuracy of cloud microphysical sensor used in contrail studies are also discussed with subsequent errors on description of cloud radiative properties. (R.P.) 9 refs.

  4. Microphysical and optical properties of contrails and cirrus

    Energy Technology Data Exchange (ETDEWEB)

    Gayet, J.F.; Febvre, G. [Universite Blaise Pascal, Clermont-Ferand (France). Lab. de Meteorologie Physique; Brogniez, G. [Universite des Sciences et Techniques de Lille, (France). Lab. d`Optique Atmospherique; Wendling, P. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Larsen, H. [National Inst. for Water and Atmospheric Research, Wellington (New Zealand)

    1997-12-31

    Aircraft contrails have significantly different properties to natural cirrus clouds. Their local and global climate impact cannot be assessed without consideration of these differences. Microphysical data were obtained from the Merlin aircraft equipped with a PMS FSSP-100 for particle spectrum measurements over the 3 {mu}m to 45 {mu}m diameter range; a PMS 2D-C for particle size spectrum and particle shape over the size range from 25 {mu}m to 800 {mu}m and a Johnson-Williams cloud liquid-water probe. Radiative measurements were obtained from a Do228 aircraft which carried the upward looking ALEX-F Lidar operating at a wavelength of 1.06 {mu}m and a Barnes PRT-5 radiometer aligned parallel to the lidar and with a 9 to 11 {mu}m spectral range. The limitation in accuracy of cloud microphysical sensor used in contrail studies are also discussed with subsequent errors on description of cloud radiative properties. (R.P.) 9 refs.

  5. Sensitivity of surface temperature to radiative forcing by contrail cirrus in a radiative-mixing model

    Directory of Open Access Journals (Sweden)

    U. Schumann

    2017-11-01

    Full Text Available Earth's surface temperature sensitivity to radiative forcing (RF by contrail cirrus and the related RF efficacy relative to CO2 are investigated in a one-dimensional idealized model of the atmosphere. The model includes energy transport by shortwave (SW and longwave (LW radiation and by mixing in an otherwise fixed reference atmosphere (no other feedbacks. Mixing includes convective adjustment and turbulent diffusion, where the latter is related to the vertical component of mixing by large-scale eddies. The conceptual study shows that the surface temperature sensitivity to given contrail RF depends strongly on the timescales of energy transport by mixing and radiation. The timescales are derived for steady layered heating (ghost forcing and for a transient contrail cirrus case. The radiative timescales are shortest at the surface and shorter in the troposphere than in the mid-stratosphere. Without mixing, a large part of the energy induced into the upper troposphere by radiation due to contrails or similar disturbances gets lost to space before it can contribute to surface warming. Because of the different radiative forcing at the surface and at top of atmosphere (TOA and different radiative heating rate profiles in the troposphere, the local surface temperature sensitivity to stratosphere-adjusted RF is larger for SW than for LW contrail forcing. Without mixing, the surface energy budget is more important for surface warming than the TOA budget. Hence, surface warming by contrails is smaller than suggested by the net RF at TOA. For zero mixing, cooling by contrails cannot be excluded. This may in part explain low efficacy values for contrails found in previous global circulation model studies. Possible implications of this study are discussed. Since the results of this study are model dependent, they should be tested with a comprehensive climate model in the future.

  6. Towards a contrail climatology from NOAA-satellite images over Europe

    Energy Technology Data Exchange (ETDEWEB)

    Bakan, S [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Betancor, M [Hamburg Univ. (Germany). Meteorologisches Inst.; Gayler, V [Hamburg Univ. (Germany). Meteorologisches Inst.; Grassl, H [Hamburg Univ. (Germany). Meteorologisches Inst.; [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany)

    1993-11-01

    Contrail cloudiness over Europe and the eastern part of the North Atlantic Ocean was analyzed for the two periods Sept. 1979-Dec. 1981 and Sept. 1989-Aug. 1992 by visual inspection of quicklook photographic prints of NOAA/AVHRR infrared images. The averaged contrail cover exhibits maximum values along the transatlantic flight corridor around 50 N (of almost 2%) and over western Europe resulting in 0.5% contrail cloudiness on the average. A strong yearly cycle appears with a maximum (<2%) in spring and summer over the Atlantic and a smaller maximum (<1%) in winter over southwestern Europe. Comparing the two time periods of one decade separation there is a significant decrease in contrail cloudiness over western Europe and a significant increase over the North Atlantic observable between March and July. Contrail cloud cover during daytime is about twice as high as during nighttime. Contrails are preferably found in larger fields of 1000 km diameter which last usually for more than one day. Causes, possible errors and consequences are discussed. (orig.)

  7. Towards a contrail climatology from NOAA-satellite images over Europe

    International Nuclear Information System (INIS)

    Bakan, S.; Betancor, M.

    1993-01-01

    Contrail cloudiness over Europe and the eastern part of the North Atlantic Ocean was analyzed for the two periods Sept. 1979-Dec. 1981 and Sept. 1989-Aug. 1992 by visual inspection of quicklook photographic prints of NOAA/AVHRR infrared images. The averaged contrail cover exhibits maximum values along the transatlantic flight corridor around 50 N (of almost 2%) and over western Europe resulting in 0.5% contrail cloudiness on the average. A strong yearly cycle appears with a maximum (<2%) in spring and summer over the Atlantic and a smaller maximum (<1%) in winter over southwestern Europe. Comparing the two time periods of one decade separation there is a significant decrease in contrail cloudiness over western Europe and a significant increase over the North Atlantic observable between March and July. Contrail cloud cover during daytime is about twice as high as during nighttime. Contrails are preferably found in larger fields of 1000 km diameter which last usually for more than one day. Causes, possible errors and consequences are discussed. (orig.)

  8. Persistence and co-occurrence of demersal nurseries in the Strait of Sicily (central Mediterranean): Implications for fishery management

    Science.gov (United States)

    Garofalo, G.; Fortibuoni, T.; Gristina, M.; Sinopoli, M.; Fiorentino, F.

    2011-08-01

    This study investigated the nurseries of seven commercially important demersal species of the northern sector of the Strait of Sicily (central Mediterranean): red mullet, European hake, horned octopus, deep-water rose shrimp, greater forkbeard, Norway lobster and giant red shrimp. An eleven-year series of data collected through experimental trawling in the Strait of Sicily during spring and autumn was analyzed. The spatio-temporal persistence of the high-density aggregations (hot spots) of juvenile individuals in their first year of life was investigated to identify habitats that serve as nurseries. The density of recruits within the persistent nurseries was used as a proxy of the unit area contribution of individuals which recruit to the adult population. The spatial distribution patterns of the recruits of most the species were well defined and very stable in the long term. Persistent and potentially highly productive nurseries of European hake, deep-water rose shrimp and greater forkbeard were identified off the southern coast of Sicily. Persistent areas of recruits concentration were also observed for the other species investigated, but their specific potential contribution of individuals to the adult population was not substantial compared to adjacent grounds. The close or overlapped localization of sites which regularly host vulnerable life stages of different exploited species, revealed an area of great ecological significance which probably plays a major role in the dynamics of the fishery resources in the Strait of Sicily. Appropriate spatial protection measures of this area, including marine protected area designation, could complement conventional management approach for ensuring the long-term sustainability of these fisheries and stocks conservation.

  9. The impact of diurnal variations of air traffic on contrail radiative forcing

    Directory of Open Access Journals (Sweden)

    N. Stuber

    2007-06-01

    Full Text Available We combined high resolution aircraft flight data from the EU Fifth Framework Programme project AERO2k with analysis data from the ECMWF's integrated forecast system to calculate diurnally resolved 3-D contrail cover. We scaled the contrail cover in order to match observational data for the Bakan area (eastern-Atlantic/western-Europe.

    We found that less than 40% of the global distance travelled by aircraft is due to flights during local night time. Yet, due to the cancellation of shortwave and longwave effects during daytime, night time flights contribute a disproportional 60% to the global annual mean forcing. Under clear sky conditions the night flights contribute even more disproportionally at 76%. There are pronounced regional variations in night flying and the associated radiative forcing. Over parts of the North Atlantic flight corridor 75% of air traffic and 84% of the forcing occurs during local night, whereas only 35% of flights are during local night in South-East Asia, yet these contribute 68% of the radiative forcing. In general, regions with a significant local contrail radiative forcing are also regions for which night time flights amount to less than half of the daily total of flights. Therefore, neglecting diurnal variations in air traffic/contrail cover by assuming a diurnal mean contrail cover can over-estimate the global mean radiative forcing by up to 30%.

  10. Variability of contrail formation conditions and the implications for policies to reduce the climate impacts of aviation

    International Nuclear Information System (INIS)

    Williams, Victoria; Noland, Robert B.

    2005-01-01

    This paper describes an approach to balance the climate benefits of contrail reduction against the penalties incurred when cruise altitudes are restricted. Altitude restrictions are targeted by selecting, for each 6-h period, the altitude that provides the greatest reduction in contrail for the lowest increase in carbon dioxide emission. Calculations are for western Europe. This paper discusses the variability in contrail formation conditions in the region and presents contrail reductions and carbon dioxide emission increases obtained with this optimised approach, which compare favourably with fixed altitude restrictions. A new method is also developed to estimate contrail fractions within three-dimensional grids. Conclusions discuss potential operational issues associated with a varying altitude restriction policy. (Author)

  11. Reproductive health of bass in the potomac, USA, drainage: part 2. Seasonal occurrence of persistent and emerging organic contaminants

    Science.gov (United States)

    Alvarez, D.A.; Cranor, W.L.; Perkins, S.D.; Schroeder, V.L.; Iwanowicz, L.R.; Clark, R.C.; Guy, C.P.; Pinkney, A.E.; Blazer, V.S.; Mullican, J.E.

    2009-01-01

    The seasonal occurrence of organic contaminants, many of which are potential endocrine disruptors, entering the Potomac River, USA, watershed was investigated using a two-pronged approach during the fall of 2005 and spring of 2006. Passive samplers (semipermeable membrane device and polar organic chemical integrative sampler [POCIS]) were deployed in tandem at sites above and below wastewater treatment plant discharges within the watershed. Analysis of the samplers resulted in detection of 84 of 138 targeted chemicals. The agricultural pesticides atrazine and metolachlor had the greatest seasonal changes in water concentrations, with a 3.1 - to 91 -fold increase in the spring compared with the level in the previous fall. Coinciding with the elevated concentrations of atrazine in the spring were increasing concentrations of the atrazine degradation products desethylatrazine and desisopropylatrazine in the fall following spring and summer application of the parent compound. Other targeted chemicals (organochlorine pesticides, polycyclic aromatic hydrocarbons, and organic wastewater chemicals) did not indicate seasonal changes in occurrence or concentration; however, the overall concentrations and number of chemicals present were greater at the sites downstream of wastewater treatment plant discharges. Several fragrances and flame retardants were identified in these downstream sites, which are characteristic of wastewater effluent and human activities. The bioluminescent yeast estrogen screen in vitro assay of the POCIS extracts indicated the presence of chemicals that were capable of producing an estrogenic response at all sampling sites. ?? 2009 SETA.

  12. Ground-based mobile scanning LIDAR for remote sensing of contrails

    Directory of Open Access Journals (Sweden)

    F. Homburg

    Full Text Available Air traffic is a source of trace gases in the upper troposphere and lower stratosphere. Contrails readily form from water vapor exhausts under favorable meteorological conditions. Since contrails are ice crystal clouds like natural cirrus clouds, they bear a greenhouse potential which has to be investigated. The IFU has built a scanning lidar system employing a pulsed Nd:YAG laser as the emitter and a 52-cm diameter telescope as the receiver. Signals are processed in several channels to investigate depolarization and wavelength dependencies of the light backscattered from ice crystals. These investigations are aimed at the formation and life cycles of contrails, their optical properties, and their climatological consequences in areas of dense air traffic. The experimental lidar setup is described and a sample measurement is shown.

  13. Ground-based mobile scanning LIDAR for remote sensing of contrails

    Directory of Open Access Journals (Sweden)

    V. Freudenthaler

    1994-08-01

    Full Text Available Air traffic is a source of trace gases in the upper troposphere and lower stratosphere. Contrails readily form from water vapor exhausts under favorable meteorological conditions. Since contrails are ice crystal clouds like natural cirrus clouds, they bear a greenhouse potential which has to be investigated. The IFU has built a scanning lidar system employing a pulsed Nd:YAG laser as the emitter and a 52-cm diameter telescope as the receiver. Signals are processed in several channels to investigate depolarization and wavelength dependencies of the light backscattered from ice crystals. These investigations are aimed at the formation and life cycles of contrails, their optical properties, and their climatological consequences in areas of dense air traffic. The experimental lidar setup is described and a sample measurement is shown.

  14. Carbon balance of China constrained by CONTRAIL aircraft CO2 measurements

    Science.gov (United States)

    Jiang, F.; Wang, H. M.; Chen, J. M.; Machida, T.; Zhou, L. X.; Ju, W. M.; Matsueda, H.; Sawa, Y.

    2014-09-01

    Terrestrial carbon dioxide (CO2) flux estimates in China using atmospheric inversion method are beset with considerable uncertainties because very few atmospheric CO2 concentration measurements are available. In order to improve these estimates, nested atmospheric CO2 inversion during 2002-2008 is performed in this study using passenger aircraft-based CO2 measurements over Eurasia from the Comprehensive Observation Network for Trace gases by Airliner (CONTRAIL) project. The inversion system includes 43 regions with a focus on China, and is based on the Bayesian synthesis approach and the TM5 transport model. The terrestrial ecosystem carbon flux modeled by the Boreal Ecosystems Productivity Simulator (BEPS) model and the ocean exchange simulated by the OPA-PISCES-T model are considered as the prior fluxes. The impacts of CONTRAIL CO2 data on inverted China terrestrial carbon fluxes are quantified, the improvement of the inverted fluxes after adding CONTRAIL CO2 data are rationed against climate factors and evaluated by comparing the simulated atmospheric CO2 concentrations with three independent surface CO2 measurements in China. Results show that with the addition of CONTRAIL CO2 data, the inverted carbon sink in China increases while those in South and Southeast Asia decrease. Meanwhile, the posterior uncertainties over these regions are all reduced (2-12%). CONTRAIL CO2 data also have a large effect on the inter-annual variation of carbon sinks in China, leading to a better correlation between the carbon sink and the annual mean climate factors. Evaluations against the CO2 measurements at three sites in China also show that the CONTRAIL CO2 measurements may have improved the inversion results.

  15. Thermophilic methanogenic Archaea in compost material: occurrence, persistence and possible mechanisms for their distribution to other environments.

    Science.gov (United States)

    Thummes, Kathrin; Schäfer, Jenny; Kämpfer, Peter; Jäckel, Udo

    2007-12-01

    Since compost is widely used as soil amendment and the fact that during the processing of compost material high amounts of microorganisms are released into the air, we investigated whether compost may act as a carrier for thermophilic methanogens to temperate soils. All eight investigated compost materials showed a clear methane production potential between 0.01 and 0.98 micromol CH(4) g dw(-1)h(-1) at 50 degrees C. Single strand conformation polymorphism (SSCP) and cloning analysis indicated the presence of Methanosarcina thermophila, Methanoculleus thermophilus, and Methanobacterium formicicum. Bioaerosols collected during the turning of a compost pile showed both a highly similar SSCP profile compared to the corresponding compost material and clear methane production during anoxic incubation in selective medium at 50 degrees C. Both observations indicated a considerable release of thermophilic methanogens into the air. To analyse the persistence of compost-borne thermophilic methanogens in temperate oxic soils, we therefore studied their potential activity in compost and compost/soil mixtures, which was brought to a meadow soil, as well as in an agricultural soil fertilised with compost. After 24h anoxic incubation at 50 degrees C, all samples containing compost showed a clear methanogenic activity, even 1 year after application. In combination with the in vitro observed resilience of the compost-borne methanogens against desiccation and UV radiation we assume that compost material acts as an effective carrier for the distribution of thermophilic methanogens by fertilisation and wind.

  16. Influence of continuous illumination on estrous cycle of rats: time course of changes in levels of gonadotropins and ovarian steroids until occurrence of persistent estrus.

    Science.gov (United States)

    Takeo, Y

    1984-08-01

    Plasma concentrations of LH, FSH, 17 beta-estradiol, estrone and progesterone were determined chronologically by radioimmunoassays in two groups of adult female rats exposed to continuous illumination (LL). Group 1 rats showing vaginal estrous cycles were sacrificed at 3- to 6-hour intervals during late proestrus through early estrus of the first 5 cycles after exposure to LL. Group 2 animals which displayed persistent vaginal estrus in an early period of exposure to LL were killed on the 2nd, 3rd, 4th, 5th and 7th days of vaginal estrus. In Group 1 rats, surges of the hormones, except estrone, took place in all the 5 cycles. The occurrence of peak hormone levels in each cycle was invariably delayed after transfer of animals to LL. According to regression analyses, the lengths of secretion cycles of LH, FSH, 17 beta-estradiol and progesterone in rats under LL were 100.89, 100.46, 101.14 and 101.06 h, respectively. Elevation of 17 beta-estradiol levels was observed prior to the LH surge, and peaks of progesterone and FSH occurred following it. However, the secretion patterns of these hormones appear to be disrupted with length of exposure to LL. In group 2 rats, the mean concentration of LH during persistent estrus was approximately similar to that on the morning of the days of proestrus of the 4-day cycles of rats placed under an alternating 12-hour light-dark regimen (LD), whereas the mean FSH concentration was continuously low. While the concentrations of 17 beta-estradiol and estrone in persistent-estrous rats were elevated, progesterone levels remained low.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Intercomparison of radiative forcing calculations of stratospheric water vapour and contrails

    Energy Technology Data Exchange (ETDEWEB)

    Myhre, Gunnar [Dept. of Geosciences, Univ. of Oslo (Norway); Center for International Climate and Environmental Research-Oslo (CICERO), Oslo (Norway); Kvalevaag, Maria [Dept. of Geosciences, Univ. of Oslo (Norway); Raedel, Gaby; Cook, Jolene; Shine, Keith P. [Dept. of Meteorology, Univ. of Reading (United Kingdom); Clark, Hannah [CNRM/GAME Meteo France, Toulouse (France); Lab. d' Aerologie, Univ. de Toulouse (France); Karcher, Fernand [CNRM/GAME Meteo France, Toulouse (France); Markowicz, Krzysztof; Kardas, Aleksandra; Wolkenberg, Paulina [Inst. of Geophysics, Univ. of Warsaw (Poland); Balkanski, Yves [LSCE/IPSL, Lab. CEA-CNRS-UVSQ (France); Ponater, Michael [Deutsches Zentrum fuer Luft und Raumfahrt (DLR), Inst. fuer Physik der Atmosphaere, Oberpfaffenhofen (Germany); Forster, Piers; Rap, Alexandru [School of Earth and Environment, Univ. of Leeds (United Kingdom); Leon, Ruben Rodriguez de [Manchester Metropolitan Univ. (United Kingdom)

    2009-12-15

    Seven groups have participated in an intercomparison study of calculations of radiative forcing (RF) due to stratospheric water vapour (SWV) and contrails. a combination of detailed radiative transfer schemes and codes for global-scale calculations have been used, as well as a combination of idealized simulations and more realistic global-scale changes in stratospheric water vapour and contrails. Detailed line-by-line codes agree within about 15% for longwave (LW) and shortwave (SW) RF, except in one case where the difference is 30%. Since the LW and SW RF due to contrails and SWV changes are of opposite sign, the differences between the models seen in the individual LW and SW components can be either compensated or strengthened in the net RF. and thus in relative terms uncertainties are much larger for the net RF. Some of the models used for global-scale simulations of changes in SWV and contrails differ substantially in RF from the more detailed radiative transfer schemes. For the global-scale calculations we use a method of weighting the results to calculate a best estimate based on their performance compared to the more detailed radiative transfer schemes in the idealized simulations. (orig.)

  18. Contrail Cirrus Forecasts for the ML-CIRRUS Experiment and Some Comparison Results

    Science.gov (United States)

    Schumann, Ulrich; Graf, Kaspar; Bugliaro, Luca; Dörnbrack, Andreas; Giez, Andreas; Jurkat, Tina; Kaufmann, Stefan; Krämer, Martina; Minikin, Andreas; Schäfler, Andreas; Voigt, Christiane; Wirth, Martin; Zahn, Andreas; Ziereis, Helmut

    2015-04-01

    Model simulations with the contrail cirrus prediction model CoCiP driven by numerical weather prediction (NWP) data provided from the European Centre for Medium Range Forecasts (ECMWF) and global aircraft waypoint data show a mean computed cover (for optical depth larger than 0.1) of 0.23% globally, and 5.4% over mid Europe (Schumann and Graf, JGR, 2013). The computed mean longwave radiative forcing (RF) reaches 3 W m-2 over mid Europe (10°W-20°E and 40°N-55°N), and 0.13 W m-2 globally. The global net RF is about 40-60% smaller because of compensating shortwave cooling induced by contrails during daytime. The results depend on several model details such as the number of ice particles forming from aircraft soot emissions, the contrail plume dispersion, ice particle sedimentation etc., all influencing contrail life time and their optical properties. The quantitative results depend also strongly on ambient relative humidity, vertical motion and on ice water content of other cirrus predicted by the NWP model. In order to test and possibly improve this and other contrail models, high-quality observations are needed to which multi-parameter model output can be compared. The Mid-Latitude Cirrus Experiment ML-CIRRUS was performed (see C. Voigt et al., this conference) with a suite of in-situ and Lidar instruments for airborne measurements on the research aircraft HALO. Before and during the mission, CoCiP was run daily to provide 3-days forecasts of contrail cover using operational ECMWF forecasts and historical traffic data. CoCiP forecast output was made available in an internet tool twice a day for experiment planning. The one-day and two-day contrail forecasts often showed only small differences. Still, most recent forecasts and detailed satellite observations results were transmitted via satellite link to the crew for onboard campaign optimization. After the campaign, a data base of realistic air traffic data has been setup from various sources, and CoCiP was

  19. Occurrence and persistence of organic emerging contaminants and priority pollutants in five sewage treatment plants of Spain: Two years pilot survey monitoring

    International Nuclear Information System (INIS)

    Bueno, M.J. Martínez; Gomez, M.J.; Herrera, S.; Hernando, M.D.; Agüera, A.

    2012-01-01

    This work summarized all results obtained during almost two-years of a monitoring programme carried out in five municipal sewage treatment plants (STPs) located in the north, centre and south-east of Spain. The study evaluated the occurrence and persistence of a group of 100 organic compounds belonging to several chemical groups (pharmaceuticals, personal care products, pesticides and metabolites). The average removal efficiencies of the STPs studied varied from 20% (erythromycin) to 99% (acetaminophen). In analysed samples, we identified a large number of compounds at mean range concentrations between 7–59,495 ng/L and 5–32,720 ng/L for influent and effluent samples, respectively. This study also identified 20 of the mostly detected and persistent compounds in wastewater effluent, of which hydrochlorothiazide, atenolol, gemfibrozil, galaxolide and three metabolites (fenofibric acid, 4-AAA and 4-FAA), presented the highest average contribution percentages, in relation to the total load of contaminants for the different STPs effluent studied. Highlights: ► The results summarize two-years of a monitoring programme. ► 100 organic compounds (priority substances and emerging contaminants) were analysed. ► The removal efficiency of 5 STPs of Spain was evaluated. ► The presence of target compounds in treated wastewater was also checked. ► The most frequently drugs detected were: antibiotics< anti-inflammatories<β-blockers. - Antibiotics and analgesics/anti-inflammatories were the most frequently drugs detected, following by some β-blockers, synthetic fragrances, lipid regulators and diuretics.

  20. In situ observations of contrail micro-physics and implications for their radiative impact

    Energy Technology Data Exchange (ETDEWEB)

    Poellot, M R [North Dakota Univ., Grand Forks, ND (United States); Arnott, W P; Hallett, J [Nevada Univ., Reno, NV (United States). Desert Research Inst.

    1998-12-31

    Increasing levels of air traffic have raised concerns about the potential effects of aircraft exhaust on the climate. Current knowledge is expanded by examining in situ data from 21 contrails sampled at altitudes of 9.3 - 12.5 km and temperatures of -47 deg C to -66 deg C. The airborne equipment allowed measurements of particles as small as 2 {mu}m in diameter, which have not previously been reported. The microphysical characteristics of the contrails, which occurred in both clear and cloudy air, are presented and compared with natural cirrus properties. Computations of the wavelength-dependent radiative properties of the sampled particle distributions are also presented and compared with laboratory measurements. Finally, implications of these findings for climatic assessment are discussed. (R.P.) 9 refs.

  1. A modelling study of the effects of different CCN on contrail formation

    Energy Technology Data Exchange (ETDEWEB)

    Gleitsmann, G; Zellner, R [Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Physikalische und Theoretische Chemie

    1998-12-31

    The formation of cloud condensation nuclei (CCN) in the jet regime of a B747 airliner at cruise has been investigated by modelling calculations using the BOAT model. Both homogeneous condensation of H{sub 2}O/H{sub 2}SO{sub 4}-mixtures and heterogeneous deposition of H{sub 2}O on soot surfaces activated by H{sub 2}SO{sub 4} were taken into account. Whereas the heterogeneous condensation leads to particles with average diameters of about 1.3 {mu}m, the homogeneously condensed H{sub 2}O/H{sub 2}SO{sub 4} particles are much smaller ({<=} 7 nm) and do not contribute to visible contrail formation. Nevertheless, they contribute to the atmospheric background aerosol. Using different SO{sub 2} emission indices, it is concluded that the contrail onset is essentially independent of this quantity and depends mainly on ambient temperature and soot activation kinetics. (author) 15 refs.

  2. A modelling study of the effects of different CCN on contrail formation

    Energy Technology Data Exchange (ETDEWEB)

    Gleitsmann, G.; Zellner, R. [Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Physikalische und Theoretische Chemie

    1997-12-31

    The formation of cloud condensation nuclei (CCN) in the jet regime of a B747 airliner at cruise has been investigated by modelling calculations using the BOAT model. Both homogeneous condensation of H{sub 2}O/H{sub 2}SO{sub 4}-mixtures and heterogeneous deposition of H{sub 2}O on soot surfaces activated by H{sub 2}SO{sub 4} were taken into account. Whereas the heterogeneous condensation leads to particles with average diameters of about 1.3 {mu}m, the homogeneously condensed H{sub 2}O/H{sub 2}SO{sub 4} particles are much smaller ({<=} 7 nm) and do not contribute to visible contrail formation. Nevertheless, they contribute to the atmospheric background aerosol. Using different SO{sub 2} emission indices, it is concluded that the contrail onset is essentially independent of this quantity and depends mainly on ambient temperature and soot activation kinetics. (author) 15 refs.

  3. In situ observations of contrail micro-physics and implications for their radiative impact

    Energy Technology Data Exchange (ETDEWEB)

    Poellot, M.R. [North Dakota Univ., Grand Forks, ND (United States); Arnott, W.P.; Hallett, J. [Nevada Univ., Reno, NV (United States). Desert Research Inst.

    1997-12-31

    Increasing levels of air traffic have raised concerns about the potential effects of aircraft exhaust on the climate. Current knowledge is expanded by examining in situ data from 21 contrails sampled at altitudes of 9.3 - 12.5 km and temperatures of -47 deg C to -66 deg C. The airborne equipment allowed measurements of particles as small as 2 {mu}m in diameter, which have not previously been reported. The microphysical characteristics of the contrails, which occurred in both clear and cloudy air, are presented and compared with natural cirrus properties. Computations of the wavelength-dependent radiative properties of the sampled particle distributions are also presented and compared with laboratory measurements. Finally, implications of these findings for climatic assessment are discussed. (R.P.) 9 refs.

  4. Numerical simulations of contrail-to-cirrus transition – Part 2: Impact of initial ice crystal number, radiation, stratification, secondary nucleation and layer depth

    Directory of Open Access Journals (Sweden)

    S. Unterstrasser

    2010-02-01

    Full Text Available Simulations of contrail-to-cirrus transition were performed with an LES model. In Part 1 the impact of relative humidity, temperature and vertical wind shear was explored in a detailed parametric study. Here, we study atmospheric parameters like stratification and depth of the supersaturated layer and processes which may affect the contrail evolution. We consider contrails in various radiation scenarios herein defined by the season, time of day and the presence of lower-level cloudiness which controls the radiance incident on the contrail layer. Under suitable conditions, controlled by the radiation scenario and stratification, radiative heating lifts the contrail-cirrus and prolongs its lifetime. The potential of contrail-driven secondary nucleation is investigated. We consider homogeneous nucleation and heterogeneous nucleation of preactivated soot cores released from sublimated contrail ice crystals. In our model the contrail dynamics triggered by radiative heating does not suffice to force homogeneous freezing of ambient liquid aerosol particles. Furthermore, our model results suggest that heterogeneous nucleation of preactivated soot cores is unimportant. Contrail evolution is not controlled by the depth of the supersaturated layer as long as it exceeds roughly 500 m. Deep fallstreaks however need thicker layers. A variation of the initial ice crystal number is effective during the whole evolution of a contrail. A cut of the soot particle emission by two orders of magnitude can reduce the contrail timescale by one hour and the optical thickness by a factor of 5. Hence future engines with lower soot particle emissions could potentially lead to a reduction of the climate impact of aviation.

  5. Alternative-Fuel Effects on Contrails & Cruise Emissions (ACCESS-2) Flight Experiment

    Science.gov (United States)

    Anderson, Bruce E.

    2015-01-01

    Although the emission performance of gas-turbine engines burning renewable aviation fuels have been thoroughly documented in recent ground-based studies, there is still great uncertainty regarding how the fuels effect aircraft exhaust composition and contrail formation at cruise altitudes. To fill this information gap, the NASA Aeronautics Research Mission Directorate sponsored the ACCESS flight series to make detailed measurements of trace gases, aerosols and ice particles in the near-field behind the NASA DC-8 aircraft as it burned either standard petroleum-based fuel of varying sulfur content or a 50:50 blend of standard fuel and a hydro-treated esters and fatty acid (HEFA) jet fuel produced from camelina plant oil. ACCESS 1, conducted in spring 2013 near Palmdale CA, focused on refining flight plans and sampling techniques and used the instrumented NASA Langley HU-25 aircraft to document DC-8 emissions and contrails on five separate flights of approx.2 hour duration. ACCESS 2, conducted from Palmdale in May 2014, engaged partners from the Deutsches Zentrum fuer Luft- und Raumfahrt (DLR) and National Research Council-Canada to provide additional scientific expertise and sampling aircraft (Falcon 20 and CT-133, respectively) with more extensive trace gas, particle, or air motion measurement capability. Eight, muliti-aircraft research flights of 2 to 4 hour duration were conducted to document the emissions and contrail properties of the DC-8 as it 1) burned low sulfur Jet A, high sulfur Jet A or low sulfur Jet A/HEFA blend, 2) flew at altitudes between 6 and 11 km, and 3) operated its engines at three different fuel flow rates. This presentation further describes the ACCESS flight experiments, examines fuel type and thrust setting impacts on engine emissions, and compares cruise-altitude observations with similar data acquired in ground tests.

  6. Kinetics of contrail particles formation and heterogeneous reactions on such particles

    Energy Technology Data Exchange (ETDEWEB)

    Kogan, M.N.; Butkovsky, A.V.; Erofeev, A.I.; Freedlender, O.G.; Makashev, N.K. [Central Aerohydrodynamic Inst., Zhukovsky (Russian Federation)

    1997-12-31

    The research of impact of aircraft emissions upon the atmosphere is very complex and difficult problem. More than two decades of intensive investigations of the problem of ozone decay do not permit to make definite conclusions. Many important problems still remain unsolved in the aircraft/atmosphere interaction: engine, nozzle, jet, jet/vortex system interaction, vortex breakdown, contrail formation, meso-scale and global processes, their effects on climate. The particles formation and heterogeneous reactions play an important role in some of these processes. These problems are discussed. (author) 11 refs.

  7. Kinetics of contrail particles formation and heterogeneous reactions on such particles

    Energy Technology Data Exchange (ETDEWEB)

    Kogan, M N; Butkovsky, A V; Erofeev, A I; Freedlender, O G; Makashev, N K [Central Aerohydrodynamic Inst., Zhukovsky (Russian Federation)

    1998-12-31

    The research of impact of aircraft emissions upon the atmosphere is very complex and difficult problem. More than two decades of intensive investigations of the problem of ozone decay do not permit to make definite conclusions. Many important problems still remain unsolved in the aircraft/atmosphere interaction: engine, nozzle, jet, jet/vortex system interaction, vortex breakdown, contrail formation, meso-scale and global processes, their effects on climate. The particles formation and heterogeneous reactions play an important role in some of these processes. These problems are discussed. (author) 11 refs.

  8. Occurrence and fate of the angiotensin II receptor antagonist transformation product valsartan acid in the water cycle--a comparative study with selected β-blockers and the persistent anthropogenic wastewater indicators carbamazepine and acesulfame.

    Science.gov (United States)

    Nödler, Karsten; Hillebrand, Olav; Idzik, Krzysztof; Strathmann, Martin; Schiperski, Ferry; Zirlewagen, Johannes; Licha, Tobias

    2013-11-01

    The substantial transformation of the angiotensin II receptor antagonist valsartan to the transformation product 2'-(2H-tetrazol-5-yl)-[1,1'-biphenyl]-4-carboxylic acid (referred to as valsartan acid) during the activated sludge process was demonstrated in the literature and confirmed in the here presented study. However, there was a severe lack of knowledge regarding the occurrence and fate of this compound in surface water and its behavior during drinking water treatment. In this work a comparative study on the occurrence and persistency of valsartan acid, three frequently used β-blockers (metoprolol, atenolol, and sotalol), atenolol acid (one significant transformation product of atenolol and metoprolol), and the two widely distributed persistent anthropogenic wastewater indicators carbamazepine and acesulfame in raw sewage, treated wastewater, surface water, groundwater, and tap water is presented. Median concentrations of valsartan acid in the analyzed matrices were 101, 1,310, 69, waters valsartan acid was found just as relevant as the analyzed β-blockers and the anticonvulsant carbamazepine. Regarding its persistency in surface waters it was comparable to carbamazepine and acesulfame. Furthermore, removal of valsartan acid during bank filtration was poor, which demonstrated the relevance of this compound for drinking water suppliers. Regarding drinking water treatment (Muelheim Process) the compound was resistant to ozonation but effectively eliminated (≥90%) by subsequent activated carbon filtration. However, without applying activated carbon filtration the compound may enter the drinking water distribution system as it was demonstrated for Berlin tap water. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Are allergic multimorbidities and IgE polysensitization associated with the persistence or re-occurrence of foetal type 2 signalling?

    DEFF Research Database (Denmark)

    Bousquet, J; Anto, J M; Wickman, M

    2015-01-01

    -occurrence of foetal type 2 signalling. Asthma, rhinitis and AD are manifestations of a common systemic immune imbalance (mesodermal origin) with specific patterns of remodelling (ectodermal or endodermal origin). This study proposes a new classification of IgE-mediated allergic diseases that allows the definition...... of novel phenotypes to (i) better understand genetic and epigenetic mechanisms, (ii) better stratify allergic preschool children for prognosis and (iii) propose novel strategies of treatment and prevention....

  10. Reproductive health of bass in the Potomac, U.S.A., drainage: part 2. Seasonal occurrence of persistent and emerging organic contaminants.

    Science.gov (United States)

    Alvarez, David A; Cranor, Walter L; Perkins, Stephanie D; Schroeder, Vickie L; Iwanowicz, Luke R; Clark, Randal C; Guy, Christopher P; Pinkney, Alfred E; Blazer, Vicki S; Mullican, John E

    2009-05-01

    The seasonal occurrence of organic contaminants, many of which are potential endocrine disruptors, entering the Potomac River, USA, watershed was investigated using a two-pronged approach during the fall of 2005 and spring of 2006. Passive samplers (semipermeable membrane device and polar organic chemical integrative sampler [POCIS]) were deployed in tandem at sites above and below wastewater treatment plant discharges within the watershed. Analysis of the samplers resulted in detection of 84 of 138 targeted chemicals. The agricultural pesticides atrazine and metolachlor had the greatest seasonal changes in water concentrations, with a 3.1- to 91-fold increase in the spring compared with the level in the previous fall. Coinciding with the elevated concentrations of atrazine in the spring were increasing concentrations of the atrazine degradation products desethylatrazine and desisopropylatrazine in the fall following spring and summer application of the parent compound. Other targeted chemicals (organochlorine pesticides, polycyclic aromatic hydrocarbons, and organic wastewater chemicals) did not indicate seasonal changes in occurrence or concentration; however, the overall concentrations and number of chemicals present were greater at the sites downstream of wastewater treatment plant discharges. Several fragrances and flame retardants were identified in these downstream sites, which are characteristic of wastewater effluent and human activities. The bioluminescent yeast estrogen screen in vitro assay of the POCIS extracts indicated the presence of chemicals that were capable of producing an estrogenic response at all sampling sites.

  11. Investigating the occurrence of persistent organic pollutants (POPs) in the arctic: their atmospheric behaviour and interaction with the seasonal snow pack

    International Nuclear Information System (INIS)

    Halsall, Crispin J.

    2004-01-01

    POPs in the Arctic are the focus of international concern due to their occurrence and accumulation in Arctic food webs. This paper presents an overview of the major pathways into the Arctic and details contemporary studies that have focused on the occurrence and transfer of POPs between the major Arctic compartments, highlighting areas where there is a lack of quantitative information. The behaviour of these chemicals in the Arctic atmosphere is scrutinised with respect to long-term trends and seasonal behaviour. Subtle differences between the PCBs and OC pesticides are demonstrated and related to sources outside of the Arctic as well as environmental processes within the Arctic. Unlike temperate regions, contaminant fate is strongly affected by the presence of snow and ice. A description of the high Arctic snow pack is given and the physical characteristics that determine chemical fate, namely the specific surface area of snow and wind driven ventilation, are discussed. Using a well-characterised fresh snow event observed at Alert (Canadian high Arctic) [Atmos. Environ. 36(2002) 2767] the flux of γ-HCH out of the snow is predicted following snow ageing. Under conditions of wind (10 m/s) it is estimated that ∼75% of the chemical may be re-emitted to the atmosphere within 24 h following snowfall, compared with just ∼5% under conditions of no wind. The implications of this are raised and areas of further research suggested. - The fluxes and fate of POPs in snowpacks are key to their behaviour in polar systems

  12. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Research Team

    Science.gov (United States)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage raft empennage.

  13. Laboratory and modeling studies on the effects of water and soot emissions and ambient conditions on the properties of contrail ice particles in the jet regime

    Directory of Open Access Journals (Sweden)

    H.-W. Wong

    2013-10-01

    Full Text Available Contrails and contrail-induced cirrus clouds are identified as the most uncertain components in determining aviation impacts on global climate change. Parameters affecting contrail ice particle formation immediately after the engine exit plane (< 5 s in plume age may be critical to ice particle properties used in large-scale models predicting contrail radiative forcing. Despite this, detailed understanding of these parametric effects is still limited. In this paper, we present results from recent laboratory and modeling studies conducted to investigate the effects of water and soot emissions and ambient conditions on near-field formation of contrail ice particles and ice particle properties. The Particle Aerosol Laboratory (PAL at the NASA Glenn Research Center and the Aerodyne microphysical parcel model for contrail ice particle formation were employed. Our studies show that exhaust water concentration has a significant impact on contrail ice particle formation and properties. When soot particles were introduced, ice particle formation was observed only when exhaust water concentration was above a critical level. When no soot or sulfuric acid was introduced, no ice particle formation was observed, suggesting that ice particle formation from homogeneous nucleation followed by homogeneous freezing of liquid water was unfavorable. Soot particles were found to compete for water vapor condensation, and higher soot concentrations emitted into the chamber resulted in smaller ice particles being formed. Chamber conditions corresponding to higher cruising altitudes were found to favor ice particle formation. The microphysical model captures trends of particle extinction measurements well, but discrepancies between the model and the optical particle counter measurements exist as the model predicts narrower ice particle size distributions and ice particle sizes nearly a factor of two larger than measured. These discrepancies are likely due to particle

  14. In-situ observations of interstitial aerosol particles and cloud residues found in contrails

    Energy Technology Data Exchange (ETDEWEB)

    Stroem, J. [Stockholm Univ. (Sweden). Dept. of Meteorology

    1997-12-31

    In spring 1994 a series of flights were conducted in cirrus clouds and contrails over southern Germany. One of the aims of this campaign was to study the phase partitioning of aerosols and water in these clouds. To achieve this separation of particles two complementary sampling probes were mounted on the research aircraft Falcon. These are the Counterflow Virtual Impactor (CVI) or super-micrometer inlet, and the interstitial inlet or submicrometer inlet. The CVI is a device that inertially separates cloud elements larger than a certain aerodynamic size from the surrounding atmosphere into a warm, dry and particle free air. Assuming that each cloud element leaves behind only one residue particle, these measurements yield an equivalent number concentration for cloud particles having an aerodynamic diameter larger than the lower cut size of the CVI. The size distribution of the sampled aerosol and residual particles between 0.1 to 3.5 {mu}m diameter was measured by a PMS PCASP (Passive Cavity Aerosol Spectrometer) working alternatively on both inlets. The gas-phase water vapor content was measured by a cryogenic frost point mirror. (R.P.) 4 refs.

  15. In-situ observations of interstitial aerosol particles and cloud residues found in contrails

    Energy Technology Data Exchange (ETDEWEB)

    Stroem, J [Stockholm Univ. (Sweden). Dept. of Meteorology

    1998-12-31

    In spring 1994 a series of flights were conducted in cirrus clouds and contrails over southern Germany. One of the aims of this campaign was to study the phase partitioning of aerosols and water in these clouds. To achieve this separation of particles two complementary sampling probes were mounted on the research aircraft Falcon. These are the Counterflow Virtual Impactor (CVI) or super-micrometer inlet, and the interstitial inlet or submicrometer inlet. The CVI is a device that inertially separates cloud elements larger than a certain aerodynamic size from the surrounding atmosphere into a warm, dry and particle free air. Assuming that each cloud element leaves behind only one residue particle, these measurements yield an equivalent number concentration for cloud particles having an aerodynamic diameter larger than the lower cut size of the CVI. The size distribution of the sampled aerosol and residual particles between 0.1 to 3.5 {mu}m diameter was measured by a PMS PCASP (Passive Cavity Aerosol Spectrometer) working alternatively on both inlets. The gas-phase water vapor content was measured by a cryogenic frost point mirror. (R.P.) 4 refs.

  16. Environmental occurrences

    International Nuclear Information System (INIS)

    Black, D.G.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report summarizes the onsite and offsite releases of radioactive and regulated materials. The specific agencies notified of the releases depended on the type, amount, and location of the individual occurrences. The more significant of these off-normal environmental occurrences are summarized in this section

  17. Environmental occurrences

    Energy Technology Data Exchange (ETDEWEB)

    Black, D.G.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the onsite and offsite releases of radioactive and regulated materials. The specific agencies notified of the releases depended on the type, amount, and location of the individual occurrences. The more significant of these off-normal environmental occurrences are summarized in this section.

  18. Regional coverage of contrails from satellite data and their radiative forcing; Regionale Kondensstreifen-Bedeckung aus Satellitendaten und ihr Einfluss auf den Strahlungshaushalt

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, R.

    2000-07-01

    An operational contrail detection algorithm is applied to day and night overpasses of the Advanced Very High Resolution Radiometer (AVHRR). From the classification results the daytime and nighttime coverage by linear shaped contrails over Western Europa is derived. The annual daytime average for the analyzed region of 0.75% shows a strong annual cycle with 1.0% coverage during winter and 0.4% during summer. The day/night ratio reaches the factor 3. Using the radiance contrasts in the 11 {mu}m channel for contrail and adjacent pixels an average visible optical depth for the observed contrails of 0.1 is derived. This leads to an annual mean top of atmosphere radiative forcing by contrails over Central Europe in the range of 0.03 W/m{sup 2} to 0.08 W/m{sup 2}, which is about one magnitude smaller than prior studies suggest. The highest annual mean contrail forcing exceeds 0.12 W/m{sup 2} over Northeastern France, Belgium, Great Britain and Hungary. (orig.) [German] Ein operationelles Kondensstreifen-Erkennungsverfahren wird auf Tag- und Nacht-Ueberfluege des Advanced Very High Resolution Radiometer (AVHRR) angewandt. Aus den Klassifizierungsergebnissen wird die mittaegliche und naechtliche Bedeckung durch linienhafte Kondensstreifen ueber Westeuropa abgeleitet. Das Jahresmittel der Bedeckung am Tag betraegt 0,75% und zeigt einen ausgepraegten Jahresgang mit 1% im Winter und 0,4% im Sommer, sowie einen starken Tag/Nacht-Unterschied mit einer Amplitude von 3. Mit Hilfe von Strahldichtekontrasten im 11 {mu}m Kanal zwischen Kondensstreifen und benachbarten Pixeln wird fuer die erkannten Kondensstreifen eine durchschnittliche optische Dicke im sichtbaren Spektralbereich von 0,1 abgeschaetzt. Daraus ergibt sich am Oberrand der Atmosphaere ein mittlerer auf Kondensstreifen zurueckzufuehrender Strahlungsantrieb zwischen 0,03 W/m{sup 2} und 0,08 W/m{sup 2}, was eine Groessenordnung unter den Ergebnissen bisheriger Studien liegt. Die hoechsten Jahresmittel mit mehr als 0,12 W

  19. Bacterial persistence

    Indian Academy of Sciences (India)

    PRAKASH KUMAR

    Drug indifference versus persistence. Studies on the mode of ... is a special case of drug indifference, restricted to a small ... to his model (outlined in detail in Lewis 2008), treatment .... belong to the heat and cold shock response family; many.

  20. [Persistent diarrhea

    Science.gov (United States)

    Andrade, J A; Moreira, C; Fagundes Neto, U

    2000-07-01

    INTRODUCTION: Persistent diarrhea has high impact on infantile morbidity and mortality rates in developing countries. Several studies have shown that 3 to 20% of acute diarrheal episodes in children under 5 years of age become persistent. DEFINITION: Persistent diarrhea is defined as an episode that lasts more than 14 days. ETIOLOGY: The most important agents isolated in persistent diarrhea are: Enteropathogenic E. coli (EPEC), Salmonella, Enteroaggregative E. coli (EAEC), Klebisiella and Cryptosporidium. CLINICAL ASPECTS: In general, the clinical characteristics of patients with persistent diarrhea do not change with the pathogenic agent. Persistent diarrhea seems to represent the final result of a several insults a infant suffers that predisposes to a more severe episode of diarrhea due to a combination of host factors and high rates of enviromental contamination. Therefore, efforts should be made to promptly treat all episodes of diarrhea with apropriate follow-up. THERAPY: The aim of the treatment is to restore hydroelectrolytic deficits and to replace losses until the diarrheal ceases. It is possible in the majority of the cases, using oral rehydration therapy and erly an appropriate type of diet. PREVENTION: It is imperative that management strategies also focus on preventive aspects. The most effective diarrheal prevention strategy in young infants worldwide is promotion of exclusive breast feeding.

  1. Persistent angina

    DEFF Research Database (Denmark)

    Jespersen, L.; Abildstrom, S. Z.; Hvelplund, Anders

    2013-01-01

    To evaluate persistent angina in stable angina pectoris with no obstructive coronary artery disease (CAD) compared to obstructive CAD and its relation to long-term anxiety, depression, quality of life (QOL), and physical functioning. We invited 357 patients (men = 191; women = 166; response rate 83......-obstructive CAD or normal coronary arteries than in patients with obstructive CAD. Persistent angina symptoms were associated with long-term anxiety, depression, impaired physical functioning, and QOL irrespective of the degree of CAD. Contrary to common perception, excluding obstructive CAD in stable angina does...... %) with no prior cardiovascular disease who had a first-time coronary angiography (CAG) in 2008-2009 due to suspected stable angina to participate in a questionnaire survey in 2011 with the Seattle Angina Questionnaire and the Hospital Anxiety and Depression Scale as key elements. Long-term persistent angina (i...

  2. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Research Team . Volume 2; Appendices

    Science.gov (United States)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage (horizontal and vertical tail). This report contains the Appendices to Volume I.

  3. Habit persistence

    DEFF Research Database (Denmark)

    Vinther Møller, Stig

    2009-01-01

    This paper uses an iterated GMM approach to estimate and test the consumption based habit persistence model of Campbell and Cochrane (1999) on the US stock market. The empirical evidence shows that the model is able to explain the size premium, but fails to explain the value premium. Further...

  4. Microbial survey of ready-to-eat salad ingredients sold at retail reveals the occurrence and the persistence of Listeria monocytogenes Sequence Types 2 and 87 in pre-packed smoked salmon.

    Science.gov (United States)

    Chau, Man Ling; Aung, Kyaw Thu; Hapuarachchi, Hapuarachchige Chanditha; Lee, Pei Sze Valarie; Lim, Pei Ying; Kang, Joanne Su Lin; Ng, Youming; Yap, Hooi Ming; Yuk, Hyun-Gyun; Gutiérrez, Ramona Alikiiteaga; Ng, Lee Ching

    2017-02-28

    As the preparation of salads involves extensive handling and the use of uncooked ingredients, they are particularly vulnerable to microbial contamination. This study aimed to determine the microbial safety and quality of pre-packed salads and salad bar ingredients sold in Singapore, so as to identify public health risks that could arise from consuming salads and to determine areas for improvement in the management of food safety. The most frequently encountered organism in pre-packed salad samples was B. cereus, particularly in pasta salads (33.3%, 10/30). The most commonly detected organism in salad bar ingredients was L. monocytogenes, in particular seafood ingredients (44.1%, 15/34), largely due to contaminated smoked salmon. Further investigation showed that 21.6% (37/171) of the pre-packed smoked salmon sold in supermarkets contained L. monocytogenes. Significantly higher prevalence of L. monocytogenes and higher Standard Plate Count were detected in smoked salmon at salad bars compared to pre-packed smoked salmon in supermarkets, which suggested multiplication of the organism as the products move down the supply chain. Further molecular analysis revealed that L. monocytogenes Sequence Type (ST) 2 and ST87 were present in a particular brand of pre-packed salmon products over a 4-year period, implying a potential persistent contamination problem at the manufacturing level. Our findings highlighted a need to improve manufacturing and retail hygiene processes as well as to educate vulnerable populations to avoid consuming food prone to L. monocytogenes contamination.

  5. Persistent Modelling

    DEFF Research Database (Denmark)

    2012-01-01

    The relationship between representation and the represented is examined here through the notion of persistent modelling. This notion is not novel to the activity of architectural design if it is considered as describing a continued active and iterative engagement with design concerns – an evident....... It also provides critical insight into the use of contemporary modelling tools and methods, together with an examination of the implications their use has within the territories of architectural design, realisation and experience....... on this subject, this book makes essential reading for anyone considering new ways of thinking about architecture. In drawing upon both historical and contemporary perspectives this book provides evidence of the ways in which relations between representation and the represented continue to be reconsidered...

  6. Persistent Modelling

    DEFF Research Database (Denmark)

    The relationship between representation and the represented is examined here through the notion of persistent modelling. This notion is not novel to the activity of architectural design if it is considered as describing a continued active and iterative engagement with design concerns – an evident....... It also provides critical insight into the use of contemporary modelling tools and methods, together with an examination of the implications their use has within the territories of architectural design, realisation and experience....... on this subject, this book makes essential reading for anyone considering new ways of thinking about architecture. In drawing upon both historical and contemporary perspectives this book provides evidence of the ways in which relations between representation and the represented continue to be reconsidered...

  7. Spatial patterns of drought persistence in East China

    Science.gov (United States)

    Meng, L.; Ford, T.

    2017-12-01

    East China has experienced a number of severe droughts in recent decades. Understanding the characteristics of droughts and their persistence will provide operational guidelines for water resource management and agricultural production. This study uses a logistic regression model to measure the probability of drought occurrence in the current season given the previous season's Standardized Precipitation Index (SPI) and Southern Oscillation Index (SOI) as well as drought persistence. Results reveal large spatial and seasonal variations in the relationship between the previous season's SPI and the drought occurrence probability in a given season. The drought persistence averaged over the entire study area for all the four seasons is approximately 34% with large variations from season to season and from region to region. The East and Northeast regions have the largest summer drought persistence ( 40%) and lowest fall drought persistence ( 28%). The spatial pattern in winter and spring drought persistence is dissimilar with stronger winter and weaker spring drought persistence in the Southwest and Northeast relative to other regions. Logistic regression analysis indicates a stronger negative relationship in summer-to-fall (or between fall drought occurrence and summer SPI) than other inter-season relationships. This study demonstrates that the impact of previous season SPI and SOI on current season drought varies substantially from region to region and from season to season. This study also shows stronger drought persistence in summer than in other seasons. In other words, the probability of fall drought occurrence is closely related to summer moisture conditions in the East China.

  8. Unusual occurrence report

    International Nuclear Information System (INIS)

    1981-01-01

    The final report provides information on an occurrence which took place in the HEDL Radioactive Liquid Waste System (RLWS), during which radioactive waste water entered the Retention Process Waste System. The RLWS has been cleared of the obstruction and is in full operation. Investigation of the occurrence and testing of the equipment involved is completed

  9. Performance Persistence of Equity Funds in Hungary

    Directory of Open Access Journals (Sweden)

    Dariusz Filip

    2011-03-01

    Full Text Available This study examines the phenomenon of performance persistence of equity funds in Hungary in two time perspectives: 1-year and 6-month perspectives. The empirical results confirm the occurrence of performance dependence in consecutive periods. There is also a strong evidence of short-term persistence in the total horizon of the study (from the beginning of 2000 to the end of 2009, and in several sub-periods. The 1-year persistence was also found in the tested sample and, in general, depended on the measure applied. Furthermore, I observed performance reversal, which can be partly explained by trend changes in the financial markets. The persistence of equity funds performance in Hungary is shaped by market factors rather than the diversity of managerial characteristics.

  10. Persistent Aerial Tracking

    KAUST Repository

    Mueller, Matthias

    2016-01-01

    persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc

  11. Demographics of antibiotic persistence

    DEFF Research Database (Denmark)

    Kollerova, Silvia; Jouvet, Lionel; Steiner, Ulrich

    Persister cells, cells that can survive antibiotic exposure but lack heritable antibiotic resistance, are assumed to play a crucial role for the evolution of antibiotic resistance. Persistence is a stage associated with reduced metabolic activity. Most previous studies have been done on batch...... even play a more prominent role for the evolution of resistance and failures of medical treatment by antibiotics as currently assumed....

  12. Persistent myalgia following whiplash.

    Science.gov (United States)

    Dommerholt, Jan

    2005-10-01

    Persistent myalgia following whiplash is commonly considered the result of poor psychosocial status, illness behavior, or failing coping skills. However, there is much evidence that persistent myalgia may be due to neurophysiologic mechanisms involving peripheral and central sensitization. Myofascial trigger points may play a crucial role in maintaining sensitization. Recent research suggests that the chemical environment of myofascial trigger points is an important factor. Several consequences are reviewed when central pain mechanisms and myofascial trigger points are included in the differential diagnosis and in the management of patients with persistent pain following whiplash.

  13. Introduction: Persistent Modelling

    DEFF Research Database (Denmark)

    Ayres, Phil

    2012-01-01

    This introduction to 'Persistent Modelling – an extended role for architectural representation' identifies how the book probes the relationship between representation and the represented, in an architectural context. It discusses how the book presents an examination and discussion of historical......, familiar contemporary and, perhaps, not so familiar emerging manifestations of this relation. What persists from this probing, fully intact, is that representation and the represented remain inextricably related in our contemporary and emerging practices. What comes into focus is that the nature...

  14. Persistent and recurrent hyperparathyroidism.

    Science.gov (United States)

    Guerin, Carole; Paladino, Nunzia Cinzia; Lowery, Aoife; Castinetti, Fréderic; Taieb, David; Sebag, Fréderic

    2017-06-01

    Despite remarkable progress in imaging modalities and surgical management, persistence or recurrence of primary hyperparathyroidism (PHPT) still occurs in 2.5-5% of cases of PHPT. The aim of this review is to expose the management of persistent and recurrent hyperparathyroidism. A literature search was performed on MEDLINE using the search terms "recurrent" or "persistent" and "hyperparathyroidism" within the past 10 years. We also searched the reference lists of articles identified by this search strategy and selected those we judged relevant. Before considering reoperation, the surgeon must confirm the diagnosis of PHPT. Then, the patient must be evaluated with new imaging modalities. A single adenoma is found in 68% of cases, multiglandular disease in 28%, and parathyroid carcinoma in 3%. Others causes (<1%) include parathyromatosis and graft recurrence. The surgeon must balance the benefits against the risks of a reoperation (permanent hypocalcemia and recurrent laryngeal nerve palsy). If surgery is necessary, a focused approach can be considered in cases of significant imaging foci, but in the case of multiglandular disease, a bilateral neck exploration could be necessary. Patients with multiple endocrine neoplasia syndromes are at high risk of recurrence and should be managed regarding their hereditary pathology. The cure rate of persistent-PHPT or recurrent-PHPT in expert centers is estimated from 93 to 97%. After confirming the diagnosis of PHPT, patients with persistent-PHPT and recurrent-PHPT should be managed in an expert center with all dedicated competencies.

  15. Persistent luminescence nanothermometers

    Science.gov (United States)

    Martín Rodríguez, Emma; López-Peña, Gabriel; Montes, Eduardo; Lifante, Ginés; García Solé, José; Jaque, Daniel; Diaz-Torres, Luis Armando; Salas, Pedro

    2017-08-01

    Persistent phosphorescence nanoparticles emitting in the red and near-infrared spectral regions are strongly demanded as contrast nanoprobes for autofluorescence free bioimaging and biosensing. In this work, we have developed Sr4Al14O25:Eu2+, Cr3+, Nd3+ nanopowders that produce persistent red phosphorescence peaking at 694 nm generated by Cr3+ ions. This emission displays temperature sensitivity in the physiological temperature range (20-60 °C), which makes these nanoparticles potentially useful as fluorescence (contactless) nanothermometers operating without requiring optical excitation. Nd3+ ions, which act as shallow electron traps for the red Cr3+ persistent emission, also display infrared emission bands, extending the fluorescence imaging capability to the second biological window. This unique combination of properties makes these nanoparticles multifunctional luminescent probes with great potential applications in nanomedicine.

  16. Persistent genital arousal disorder

    DEFF Research Database (Denmark)

    Eibye, Simone; Jensen, Hans Mørch

    2014-01-01

    We report a case of a woman suffering from persistent genital arousal disorder (PGAD) after paroxetine cessation. She was admitted to a psychiatric department and diagnosed with agitated depression. Physical investigation showed no gynaecological or neurological explanation; however, a pelvic MRI...

  17. Persistent organic pollutants

    NARCIS (Netherlands)

    Dungen, van den M.W.

    2016-01-01

    Wild caught fish, especially marine fish, can contain high levels of persistent organic pollutants (POPs). In the Netherlands, especially eel from the main rivers have high POP levels. This led to a ban in 2011 on eel fishing due to health concerns. Many of the marine POPs have been related to

  18. Contributions to Persistence Theory

    Directory of Open Access Journals (Sweden)

    Du Dong

    2014-12-01

    Full Text Available Persistence theory discussed in this paper is an application of algebraic topology (Morse Theory [29] to Data Analysis, precisely to qualitative understanding of point cloud data, or PCD for short. PCD can be geometrized as a filtration of simplicial complexes (Vietoris-Rips complex [25] [36] and the homology changes of these complexes provide qualitative information about the data. Bar codes describe the changes in homology with coefficients in a fixed field. When the coefficient field is ℤ2, the calculation of bar codes is done by ELZ algorithm (named after H. Edelsbrunner, D. Letscher, and A. Zomorodian [20]. When the coefficient field is ℝ, we propose an algorithm based on the Hodge decomposition [17]. With Dan Burghelea and Tamal K. Dey we developed a persistence theory which involves level sets discussed in Section 4. We introduce and discuss new computable invariants, the “relevant level persistence numbers” and the “positive and negative bar codes”, and explain how they are related to the bar codes for level persistence. We provide enhancements and modifications of ELZ algorithm to calculate such invariants and illustrate them by examples.

  19. Is corruption really persistent?

    NARCIS (Netherlands)

    Seldadyo, H.; de Haan, J.

    Theoretical and empirical research on corruption generally concludes that corruption is persistent. However, using International Country Risk Guide data for the period 1984-2008 for 101 countries, we find strong evidence that corruption changes over time. In the present study, corruption levels of

  20. Local persistence and blocking in the two-dimensional blume-capel model

    OpenAIRE

    Silva, Roberto da; Dahmen, S. R.

    2004-01-01

    In this paper we study the local persistence of the two-dimensional Blume-Capel Model by extending the concept of Glauber dynamics. We verify that for any value of the ratio alpha = D/J between anisotropy D and exchange J the persistence shows a power law behavior. In particular for alpha 0 (a ¹ 1) we observe the occurrence of blocking.

  1. Persistent Hiccups Following Stapedectomy

    Directory of Open Access Journals (Sweden)

    Aidonis I

    2010-10-01

    Full Text Available Objective: We report a case of a 37 year-old man who developed persistent hiccups after elective stapedectomy. Method and Results: The diagnostic approach is discussed as well as the non-pharmacologic and pharmacologic treatments and overall management. The aim is to stress that there is a variety of potential factors that can induce hiccups perioperatively and in cases like this a step by step approach must be taken. Conclusion: Persistent hiccups are very rare following stapedectomy, control of them is crucial for the successful outcome. The trigger may be more than one factors and the good response to treatment may be due to dealing successfully with more than one thing.

  2. Persistent facial pain conditions

    DEFF Research Database (Denmark)

    Forssell, Heli; Alstergren, Per; Bakke, Merete

    2016-01-01

    Persistent facial pains, especially temporomandibular disorders (TMD), are common conditions. As dentists are responsible for the treatment of most of these disorders, up-to date knowledge on the latest advances in the field is essential for successful diagnosis and management. The review covers...... TMD, and different neuropathic or putative neuropathic facial pains such as persistent idiopathic facial pain and atypical odontalgia, trigeminal neuralgia and painful posttraumatic trigeminal neuropathy. The article presents an overview of TMD pain as a biopsychosocial condition, its prevalence......, clinical features, consequences, central and peripheral mechanisms, diagnostic criteria (DC/TMD), and principles of management. For each of the neuropathic facial pain entities, the definitions, prevalence, clinical features, and diagnostics are described. The current understanding of the pathophysiology...

  3. Persistent Model #2

    DEFF Research Database (Denmark)

    2013-01-01

    Tensegrity structures and Inflatable membranes can be considered analogous. They can both be described as pressure based systems in which a coherent envelope is tensioned through compressive force in order to achieve a state of self-equilibrium. Persistent Model #2 is a full-scale speculative pro...... Modelling and a sustained critical investigation of the roles digital tools can play in extending the ways in which we think, design, realise and experience architecture....

  4. Intergenerational Top Income Persistence

    DEFF Research Database (Denmark)

    Munk, Martin D.; Bonke, Jens; Hussain, M. Azhar

    2016-01-01

    In this paper, we investigate intergenerational top earnings and top income mobility in Denmark. Access to administrative registers allowed us to look at very small fractions of the population. We find that intergenerational mobility is lower in the top when including capital income in the income...... measure— for the rich top 0.1% fathers and sons the elasticity is 0.466. Compared with Sweden, however, the intergenerational top income persistence is about half the size in Denmark....

  5. Numeric invariants from multidimensional persistence

    Energy Technology Data Exchange (ETDEWEB)

    Skryzalin, Jacek [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carlsson, Gunnar [Stanford Univ., Stanford, CA (United States)

    2017-05-19

    In this paper, we analyze the space of multidimensional persistence modules from the perspectives of algebraic geometry. We first build a moduli space of a certain subclass of easily analyzed multidimensional persistence modules, which we construct specifically to capture much of the information which can be gained by using multidimensional persistence over one-dimensional persistence. We argue that the global sections of this space provide interesting numeric invariants when evaluated against our subclass of multidimensional persistence modules. Lastly, we extend these global sections to the space of all multidimensional persistence modules and discuss how the resulting numeric invariants might be used to study data.

  6. China's water pollution by persistent organic pollutants

    International Nuclear Information System (INIS)

    Bao Lianjun; Maruya, Keith A.; Snyder, Shane A.; Zeng, Eddy Y.

    2012-01-01

    Available data were reviewed to assess the status of contamination by persistent organic pollutants (POPs), including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), in drinking water sources and coastal waters of China. The levels of POPs in China's waters were generally at the high end of the global range. A comparison of China's regulatory limits indicated that PCBs in rivers and coastal water may pose potential human health risk. Occurrence of DDTs in some rivers of China may also pose health risk to humans using the regulatory limits of DDTs recommended by the European Union. Future monitoring of POPs in China's waters should be directed towards analytes of concern (e.g. PCBs and PCDD/Fs) and to fill data gaps for analytes (e.g. PBDEs, PCDD/Fs, and chlordane) and in watersheds/regions (e.g. West China) where data are scarce. - Highlights: ► Levels of POPs in China's aquatic systems were generally at the high end of the global range. ► New inputs of DDTs, likely related to the use of dicofol and anti-fouling paints, were found. ► Occurrence of PCBs and DDTs in some water bodies pay pose potential human health risk. ► Long-term monitoring of POPs in China's waters is needed to fill data gaps. - Occurrence, potential sources and ecological and human health risk of persistent organic pollutants in China's waters are reviewed.

  7. Inflation persistence and flexible prices

    OpenAIRE

    Robert Dittmar; William T. Gavin; Finn E. Kydland

    2004-01-01

    If the central bank follows an interest rate rule, then inflation is likely to be persistence, even when prices are fully flexible. Any shock, whether persistent or not, may lead to inflation persistence. In equilibrium, the dynamics of inflation are determined by the evolution of the spread between the real interest rate and the central bank’s target. Inflation persistence in U.S. data can be characterized by a vector autocorrelation function relating inflation and deviations of output from ...

  8. Reflections on Student Persistence

    Directory of Open Access Journals (Sweden)

    Vincent Tinto

    2017-07-01

    Full Text Available The Feature for this issue Reflections on Student Persistence has been prepared by Professor Vincent Tinto, Distinguished University Professor Emeritus at Syracuse University, United States of America (USA and a longtime friend and supporter of STARS. Vincent explores the case for motivation to be considered as a significant aspect of the tertiary student psyche by drawing on theoretical frameworks, research and practical experiences related to the issue. He synthesises this extensive, detailed, rich but often somewhat impenetrable data into a trilogy of clear and credible key dimensions of the motivation construct student self efficacy, sense of belonging and perceived value of the curriculum. This interpretation of the literature is a personal but informed reflection and is a timely piece which highlights the breadth and profundity of the presentations at this year's conference in Adelaide, Australia where students in all their diversity are central to our focus on enhancing the student experience. In this opening article, Vincent refers directly to the STARS papers selected for this Conference issue of the Journal which also address the importance of student persistence, self-efficacy and building the sense of belonging within their own institutional communities (Fernandes, Ford, Rayner & Pretorius; Kahu, Nelson, & Picton; McFarlane, Spes-Skrbis & Taib; Naylor; Smallhorn. Echoing his position on social justice and his advocacy for underserved students, Vincent reminds us that educational equity gaps still exist, and he encourages us to see the issue of persistence through the eyes of the students to support their perseverance and completion and thereby help reduce educational disadvantage.

  9. Persistent marine debris

    International Nuclear Information System (INIS)

    Levy, E.M.

    1992-01-01

    In this paper the distribution of persistent marine debris, adrift on world oceans and stranded on beaches globally, is reviewed and related to the known inputs and transport by the major surface currents. Since naturally occurring processes eventually degrade petroleum in the environment, international measures to reduce the inputs have been largely successful in alleviating oil pollution on a global, if not on a local, scale. Many plastics, however, are so resistant to natural degradation that merely controlling inputs will be insufficient, and more drastic and costly measures will be needed to cope with the emerging global problem posed by these materials

  10. Persistent postsurgical pain

    DEFF Research Database (Denmark)

    Werner, Mads Utke; Bischoff, Joakim Mutahi

    2014-01-01

    The prevalences of severe persistent postsurgical pain (PPP) following breast cancer surgery (BCS), groin hernia repair (GHR), and lung cancer surgery (LCS) are 13, 2, and 4-12 %, respectively. Estimates indicate that 80,000 patients each year in the U.S.A. are affected by severe pain...... duration of surgery, repeat surgery, more invasive surgical techniques, and intraoperative nerve lesion have been associated with PPP. One of the most consistent predictive factors for PPP is high intensity acute postsurgical pain, but also psychological factors including anxiety, catastrophizing trait...

  11. Term Structure Persistence

    OpenAIRE

    Abbritti, M. (Mirko); Gil-Alana, L.A. (Luis A.); Lovcha, Y. (Yuliya); Moreno, A. (Antonio)

    2012-01-01

    Stationary I(0) models employed in yield curve analysis typically imply an unrealistically low degree of volatility in long-run short-rate expectations due to fast mean reversion. In this paper we propose a novel multivariate affine term structure model with a two-fold source of persistence in the yield curve: Long-memory and short-memory. Our model, based on an I(d) specification, nests the I(0) and I(1) models as special cases and the I(0) model is decisively rejected by the data. Our model...

  12. Persistence of Salmonid Redds

    Science.gov (United States)

    Buffington, J. M.; Buxton, T.; Fremier, A. K.; Hassan, M. A.; Yager, E.

    2013-12-01

    The construction of redds by spawning salmonids modifies fluvial processes in ways that are beneficial to egg and embryo survival. Redd topography induces hyporheic flow that oxygenates embryos incubating within the streambed and creates form drag that reduces bed mobility and scour of salmonid eggs. Winnowing of fine material during redd construction also coarsens the streambed, increasing bed porosity and hyporheic flow and reducing bed mobility. In addition to the biological benefits, redds may influence channel morphology by altering channel hydraulics and bed load transport rates depending on the size and extent of redds relative to the size of the channel. A key question is how long do the physical and biological effects of redds last? Field observations indicate that in some basins redds are ephemeral, with redd topography rapidly erased by subsequent floods, while in other basins, redds can persist for years. We hypothesize that redd persistence is a function of basin hydrology, sediment supply, and characteristics of the spawning fish. Hydrology controls the frequency and magnitude of bed mobilizing flows following spawning, while bed load supply (volume and caliber) controls the degree of textural fining and consequent bed mobility after spawning, as well as the potential for burial of redd features. The effectiveness of flows in terms of their magnitude and duration depend on hydroclimate (i.e., snowmelt, rainfall, or transitional hydrographs), while bed load supply depends on basin geology, land use, and natural disturbance regimes (e.g., wildfire). Location within the stream network may also influence redd persistence. In particular, lakes effectively trap sediment and regulate downstream flow, which may promote long-lived redds in stream reaches below lakes. These geomorphic controls are modulated by biological factors: fish species (size of fish controls size of redds and magnitude of streambed coarsening); life history (timing of spawning and

  13. Persistence extends reciprocity.

    Science.gov (United States)

    Kurokawa, Shun

    2017-04-01

    One key potential explanation for the evolution of cooperation is conditional cooperation. This allows cooperation to evolve for cooperators who switch their behavior on the basis of information about the opponent's behavior or reputation. However, information about the opponent's behavior or reputation is sometimes unavailable, and previous studies have assumed that a player cooperates with some default probability when no information about the opponent's previous behavior or reputation is available. This default probability has been interpreted as the player's "optimism". Here, we make use of the fact that even if a player cannot observe the opponent's previous behavior or reputation, he may still condition his future behavior based on his own past behavior and in such a case, he can behave persistently. In this paper, we especially consider the case where information about the opponent's "behavior" is sometimes absent and the iterated prisoner's dilemma game between the same two individuals is played. Here, we examine the evolution of strategies that can refer to the own behavior in the previous round. Using evolutionarily stable strategy (ESS) analysis and analyzing replicator dynamics, we find that conditioning his future behavior based on his own past behavior is beneficial for the evolution. Persistence facilitates the evolution of cooperation. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Persistence of airline accidents.

    Science.gov (United States)

    Barros, Carlos Pestana; Faria, Joao Ricardo; Gil-Alana, Luis Alberiko

    2010-10-01

    This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927-2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non-stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long-run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation. © 2010 The Author(s). Journal compilation © Overseas Development Institute, 2010.

  15. Occurrence of Furnonisins B2 and B4 in Retail Raisins

    DEFF Research Database (Denmark)

    Knudsen, Peter Boldsen; Mogensen, Jesper Mølgaard; Larsen, Thomas Ostenfeld

    2011-01-01

    Concerns that raisins may be contaminated by fumonisins stem from the persistent occurrence of Aspergillus niger spores on raisins and the recent discovery of fumonisin production by A. niger on grapes, which leads to the widespread occurrence of fumonisin B-2 in wine. This study presents an LC-M...... that the fumonisins are produced mainly during the drying process concomitant with the decreasing water activity. Analysis of multiple packages from one manufacturer showed a 3-fold package-to-package variation, suggesting that a few raisins per package are contaminated.......Concerns that raisins may be contaminated by fumonisins stem from the persistent occurrence of Aspergillus niger spores on raisins and the recent discovery of fumonisin production by A. niger on grapes, which leads to the widespread occurrence of fumonisin B-2 in wine. This study presents an LC...

  16. Caliber-Persistent Artery

    Directory of Open Access Journals (Sweden)

    Sabrina Araújo Pinho Costa

    2015-01-01

    Full Text Available Caliber-persistent artery (CPLA of the lip is a common vascular anomaly in which a main arterial branch extends to the surface of the mucous tissue with no reduction in its diameter. It usually manifests as pulsatile papule, is easily misdiagnosed, and is observed more frequently among older people, suggesting that its development may involve a degenerative process associated with aging; CPLA is also characterized by the loss of tone of the adjacent supporting connective tissue. Although the diagnosis is clinical, high-resolution Doppler ultrasound is a useful noninvasive tool for evaluating the lesion. This report describes the case of a 58-year-old male patient who complained of a lesion of the lower lip with bleeding and recurrent ulceration. The patient was successfully treated in our hospital after a diagnosis of CPLA and is currently undergoing a clinical outpatient follow-up with no complaints.

  17. An annoying persistent cough

    Directory of Open Access Journals (Sweden)

    Francesco Cipollini

    2007-03-01

    Full Text Available Chronic cough is a stressful condition and can lead to extensive investigations. We report a case of a 48-year-old woman who had suffered from persistent chronic cough for more than 3 months. She had been treated with cough suppressant. However, her cough was not alleviated by these treatments, and the patient was referred to our hospital. She did not exhibit typical gastroesophageal reflux disease (GERD symptoms heartburn and regurgitation. Esophagoscopy did not disclose reflux esophagitis. The patient was treated with a proton-pump inhibitor, which markedly alleviated her cough. Chronic cough due to GERD was diagnosed. Although the diagnosis of chronic cough due to GERD is not easy when traditionally symptoms are not present, our case report underscores the importance of this association to the differential diagnosis of chronic cough. In these cases a relatively simple test as high dose proton pump-inhibitors trial may be useful to confirm GERD related cough.

  18. New daily persistent headache

    Directory of Open Access Journals (Sweden)

    Alok Tyagi

    2012-01-01

    Full Text Available New daily persistent headache (NDPH is a chronic headache developing in a person who does not have a past history of headaches. The headache begins acutely and reaches its peak within 3 days. It is important to exclude secondary causes, particularly headaches due to alterations in cerebrospinal fluid (CSF pressure and volume. A significant proportion of NDPH sufferers may have intractable headaches that are refractory to treatment. The condition is best viewed as a syndrome rather than a diagnosis. The headache can mimic chronic migraine and chronic tension-type headache, and it is also important to exclude secondary causes, particularly headaches due to alterations in CSF pressure and volume. A large proportion of NDPH sufferers have migrainous features to their headache and should be managed with treatments used for treating migraine. A small group of NDPH sufferers may have intractable headaches that are refractory to treatment.

  19. Persistent idiopathic facial pain

    DEFF Research Database (Denmark)

    Maarbjerg, Stine; Wolfram, Frauke; Heinskou, Tone Bruvik

    2017-01-01

    Introduction: Persistent idiopathic facial pain (PIFP) is a poorly understood chronic orofacial pain disorder and a differential diagnosis to trigeminal neuralgia. To address the lack of systematic studies in PIFP we here report clinical characteristics and neuroimaging findings in PIFP. Methods...... pain 7 (13%), hypoesthesia 23 (48%), depression 16 (30%) and other chronic pain conditions 17 (32%) and a low prevalence of stabbing pain 21 (40%), touch-evoked pain 14 (26%) and remission periods 10 (19%). The odds ratio between neurovascular contact and the painful side was 1.4 (95% Cl 0.4–4.4, p = 0.......565) and the odds ratio between neurovascular contact with displacement of the trigeminal nerve and the painful side was 0.2 (95% Cl 0.0–2.1, p = 0.195). Conclusion: PIFP is separated from trigeminal neuralgia both with respect to the clinical characteristics and neuroimaging findings, as NVC was not associated...

  20. Persistent Aerial Tracking

    KAUST Repository

    Mueller, Matthias

    2016-04-13

    In this thesis, we propose a new aerial video dataset and benchmark for low altitude UAV target tracking, as well as, a photo-realistic UAV simulator that can be coupled with tracking methods. Our benchmark provides the rst evaluation of many state of-the-art and popular trackers on 123 new and fully annotated HD video sequences captured from a low-altitude aerial perspective. Among the compared trackers, we determine which ones are the most suitable for UAV tracking both in terms of tracking accuracy and run-time. We also present a simulator that can be used to evaluate tracking algorithms in real-time scenarios before they are deployed on a UAV "in the field", as well as, generate synthetic but photo-realistic tracking datasets with free ground truth annotations to easily extend existing real-world datasets. Both the benchmark and simulator will be made publicly available to the vision community to further research in the area of object tracking from UAVs. Additionally, we propose a persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc.) integrating multiple UAVs with a stabilized RGB camera. A novel strategy is employed to successfully track objects over a long period, by \\'handing over the camera\\' from one UAV to another. We integrate the complete system into an off-the-shelf UAV, and obtain promising results showing the robustness of our solution in real-world aerial scenarios.

  1. Does probability of occurrence relate to population dynamics?

    Science.gov (United States)

    Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H; Georges, Damien; Dullinger, Stefan; Eckhart, Vincent M; Edwards, Thomas C; Gravel, Dominique; Kunstler, Georges; Merow, Cory; Moore, Kara; Piedallu, Christian; Vissault, Steve; Zimmermann, Niklaus E; Zurell, Damaris; Schurr, Frank M

    2014-12-01

    Hutchinson defined species' realized niche as the set of environmental conditions in which populations can persist in the presence of competitors. In terms of demography, the realized niche corresponds to the environments where the intrinsic growth rate ( r ) of populations is positive. Observed species occurrences should reflect the realized niche when additional processes like dispersal and local extinction lags do not have overwhelming effects. Despite the foundational nature of these ideas, quantitative assessments of the relationship between range-wide demographic performance and occurrence probability have not been made. This assessment is needed both to improve our conceptual understanding of species' niches and ranges and to develop reliable mechanistic models of species geographic distributions that incorporate demography and species interactions. The objective of this study is to analyse how demographic parameters (intrinsic growth rate r and carrying capacity K ) and population density ( N ) relate to occurrence probability ( P occ ). We hypothesized that these relationships vary with species' competitive ability. Demographic parameters, density, and occurrence probability were estimated for 108 tree species from four temperate forest inventory surveys (Québec, Western US, France and Switzerland). We used published information of shade tolerance as indicators of light competition strategy, assuming that high tolerance denotes high competitive capacity in stable forest environments. Interestingly, relationships between demographic parameters and occurrence probability did not vary substantially across degrees of shade tolerance and regions. Although they were influenced by the uncertainty in the estimation of the demographic parameters, we found that r was generally negatively correlated with P occ , while N, and for most regions K, was generally positively correlated with P occ . Thus, in temperate forest trees the regions of highest occurrence

  2. Does probability of occurrence relate to population dynamics?

    Science.gov (United States)

    Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H.; Georges, Damien; Dullinger, Stefan; Eckhart, Vincent M.; Edwards, Thomas C.; Gravel, Dominique; Kunstler, Georges; Merow, Cory; Moore, Kara; Piedallu, Christian; Vissault, Steve; Zimmermann, Niklaus E.; Zurell, Damaris; Schurr, Frank M.

    2014-01-01

    Hutchinson defined species' realized niche as the set of environmental conditions in which populations can persist in the presence of competitors. In terms of demography, the realized niche corresponds to the environments where the intrinsic growth rate (r) of populations is positive. Observed species occurrences should reflect the realized niche when additional processes like dispersal and local extinction lags do not have overwhelming effects. Despite the foundational nature of these ideas, quantitative assessments of the relationship between range-wide demographic performance and occurrence probability have not been made. This assessment is needed both to improve our conceptual understanding of species' niches and ranges and to develop reliable mechanistic models of species geographic distributions that incorporate demography and species interactions.The objective of this study is to analyse how demographic parameters (intrinsic growth rate r and carrying capacity K ) and population density (N ) relate to occurrence probability (Pocc ). We hypothesized that these relationships vary with species' competitive ability. Demographic parameters, density, and occurrence probability were estimated for 108 tree species from four temperate forest inventory surveys (Québec, western USA, France and Switzerland). We used published information of shade tolerance as indicators of light competition strategy, assuming that high tolerance denotes high competitive capacity in stable forest environments.Interestingly, relationships between demographic parameters and occurrence probability did not vary substantially across degrees of shade tolerance and regions. Although they were influenced by the uncertainty in the estimation of the demographic parameters, we found that r was generally negatively correlated with Pocc, while N, and for most regions K, was generally positively correlated with Pocc. Thus, in temperate forest trees the regions of highest occurrence

  3. Classifying Sluice Occurrences in Dialogue

    DEFF Research Database (Denmark)

    Baird, Austin; Hamza, Anissa; Hardt, Daniel

    2018-01-01

    perform manual annotation with acceptable inter-coder agreement. We build classifier models with Decision Trees and Naive Bayes, with accuracy of 67%. We deploy a classifier to automatically classify sluice occurrences in OpenSubtitles, resulting in a corpus with 1.7 million occurrences. This will support....... Despite this, the corpus can be of great use in research on sluicing and development of systems, and we are making the corpus freely available on request. Furthermore, we are in the process of improving the accuracy of sluice identification and annotation for the purpose of created a subsequent version...

  4. Persistent homology of complex networks

    International Nuclear Information System (INIS)

    Horak, Danijela; Maletić, Slobodan; Rajković, Milan

    2009-01-01

    Long-lived topological features are distinguished from short-lived ones (considered as topological noise) in simplicial complexes constructed from complex networks. A new topological invariant, persistent homology, is determined and presented as a parameterized version of a Betti number. Complex networks with distinct degree distributions exhibit distinct persistent topological features. Persistent topological attributes, shown to be related to the robust quality of networks, also reflect the deficiency in certain connectivity properties of networks. Random networks, networks with exponential connectivity distribution and scale-free networks were considered for homological persistency analysis

  5. Rarity and persistence.

    Science.gov (United States)

    Vermeij, Geerat J; Grosberg, Richard K

    2018-01-01

    Rarity is a population characteristic that is usually associated with a high risk of extinction. We argue here, however, that chronically rare species (those with low population densities over many generations across their entire ranges) may have individual-level traits that make populations more resistant to extinction. The major obstacle to persistence at low density is successful fertilisation (union between egg and sperm), and chronically rare species are more likely to survive when (1) fertilisation occurs inside or close to an adult, (2) mate choice involves long-distance signals, (3) adults or their surrogate gamete dispersers are highly mobile, or (4) the two sexes are combined in a single individual. In contrast, external fertilisation and wind- or water-driven passive dispersal of gametes, or sluggish or sedentary adult life habits in the absence of gamete vectors, appear to be incompatible with sustained rarity. We suggest that the documented increase in frequency of these traits among marine genera over geological time could explain observed secular decreases in rates of background extinction. Unanswered questions remain about how common chronic rarity actually is, which traits are consistently associated with chronic rarity, and how chronically rare species are distributed among taxa, and among the world's ecosystems and regions. © 2017 John Wiley & Sons Ltd/CNRS.

  6. First natural occurrence of coesite

    Science.gov (United States)

    Chao, E.C.T.; Shoemaker, E.M.; Madsen, B.M.

    1960-01-01

    Coesite, the high-pressure polymorph of SiO2, hitherto known only as a synthetic compound, is identified as an abundant mineral in sheared Coconino sandstone at Meteor Crater, Arizona. This natural occurrence has important bearing on the recognition of meteorite impact craters in quartz-bearing geologic formations.

  7. Human plague occurrences in Africa

    DEFF Research Database (Denmark)

    Neerinckx, Simon; Bertherat, Eric; Leirs, Herwig

    2010-01-01

    Plague remains a public health concern worldwide, but particularly in Africa. Despite the long-standing history of human plague, it is difficult to get a historical and recent overview of the general situation. We searched and screened available information sources on human plague occurrences in ...

  8. The persistence of depression score

    NARCIS (Netherlands)

    Spijker, J.; de Graaf, R.; Ormel, J.; Nolen, W. A.; Grobbee, D. E.; Burger, H.

    2006-01-01

    Objective: To construct a score that allows prediction of major depressive episode (MDE) persistence in individuals with MDE using determinants of persistence identified in previous research. Method: Data were derived from 250 subjects from the general population with new MDE according to DSM-III-R.

  9. Review: Occurrence of the pathogenic amoeba Naegleria fowleri in groundwater

    Science.gov (United States)

    Bright, Kelly R.; Gerba, Charles P.

    2017-06-01

    Naegleria fowleri is a thermophilic free-living amoeba found worldwide in soils and warm freshwater. It is the causative agent of primary amebic meningoencephalitis, a nearly always fatal disease afflicting mainly children and young adults. Humans are exposed to the organism via swimming, bathing, or other recreational activity during which water is forcefully inhaled into the upper nasal passages. Although many studies have looked at the occurrence of N. fowleri in surface waters, limited information is available regarding its occurrence in groundwater and geothermally heated natural waters such as hot springs. This paper reviews the current literature related to the occurrence of N. fowleri in these waters and the methods employed for its detection. Case reports of potential groundwater exposures are also included. Despite increased interest in N. fowleri in recent years due to well-publicized cases linked to drinking water, many questions still remain unanswered. For instance, why the organism persists in some water sources and not in others is not well understood. The role of biofilms in groundwater wells and plumbing in individual buildings, and the potential for warming due to climate change to expand the occurrence of the organism into new regions, are still unclear. Additional research is needed to address these questions in order to better understand the ecology of N. fowleri and the conditions that result in greater risks to bathers.

  10. PCDDs, PCDFs, and PCBs co-occurrence in TiO2 nanoparticles

    NARCIS (Netherlands)

    Ctistis, Georgios; Schön, Peter; Bakker, Wouter; Luthe, Gregor

    2016-01-01

    In the present study, we report on the co-occurrence of persistent organic pollutants (POPs) adsorbed on nanoparticular titanium dioxide (TiO2). We report on the finding of polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) on the

  11. Persistence, resistance, resonance

    Science.gov (United States)

    Tsadka, Maayan

    form of musical consumption and experience. The three pieces draw lines connecting different aspects of persistence, resistance, and resonance.

  12. Packaging and transportation occurrence reporting

    International Nuclear Information System (INIS)

    Needels, T.S.

    1996-01-01

    The US Department of Energy (DOE) Order 231.1 calls for the maintenance of a database for all unclassified occurrence reports (ORs). ORS provide DOE with notice of incidents and accidents that endanger the public, workers, or DOE facility operations. To fulfill this policy, the DOE Occurrence Reporting and Processing System (ORPS) was established to require DOE facilities to report and process information concerning such events. The Oak Ridge National Laboratory (ORNL) provides DOE with data and analysis of occurrence related to packaging and transportation (P and T) safety. This program produces annual reports, lessons learned bulletins, and information for the packaging and transportation home page on the Internet. The analysis and reports provided can be used as a tool for oversight and a means for DOE sites to be proactive and anticipate problems through shared knowledge and lessons learned. To illustrate, some observable trends based on 3 years of the program are given. In summary, this program shows potential problem areas that need correcting, and possible breakdowns of safety

  13. Teriparatide Induced Delayed Persistent Hypercalcemia

    Directory of Open Access Journals (Sweden)

    Nirosshan Thiruchelvam

    2014-01-01

    Full Text Available Teriparatide, a recombinant PTH, is an anabolic treatment for osteoporosis that increases bone density. Transient hypercalcemia is a reported side effect of teriparatide that is seen few hours following administration of teriparatide and resolves usually within 16 hours of drug administration. Persistent hypercalcemia, although not observed in clinical trials, is rarely reported. The current case describes a rare complication of teriparatide induced delayed persistent hypercalcemia.

  14. Persistence in the Cryptocurrency Market

    OpenAIRE

    Caporale, Guglielmo Maria; Gil-Alaña, Luis A.; Plastun, Alex

    2017-01-01

    This paper examines persistence in the cryptocurrency market. Two different long-memory methods (R/S analysis and fractional integration) are used to analyse it in the case of the four main cryptocurrencies (BitCoin, LiteCoin, Ripple, Dash) over the sample period 2013-2017. The findings indicate that this market exhibits persistence (there is a positive correlation between its past and future values), and that its degree changes over time. Such predictability represents evidence of market ine...

  15. Occurrence and distribution of persistent chlorinated hydrocarbons in the seas around India

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.

    Article deals with an evaluation of the levels of contamination of various organochlorine pesticides such as DDTs, HCHs, aldrin, dieldrin, endrin, and different congeners of polychlorinated biphenyls in different compartment of the ocean (water...

  16. Legionella and Mycobacterium Occurrence/Persistence in Homes and Office Buildings

    Science.gov (United States)

    Legionella and non-tuberculous Mycobacterium species are two of the more important environmental pathogens that cause human health effects. They contribute to the highest economic burden and one of the heaviest disease burdens of all of the waterborne pathogens that pose a risk t...

  17. Colorado quartz: occurrence and discovery

    Science.gov (United States)

    Kile, D.E.; Modreski, P.J.; Kile, D.L.

    1991-01-01

    The many varieties and associations of quartz found throughout the state rank it as one of the premier worldwide localities for that species. This paper briefly outlines the historical importance of the mineral, the mining history and the geological setting before discussing the varieties of quartz present, its crystallography and the geological enviroments in which it is found. The latter include volcanic rocks and near surface igneous rocks; pegmatites; metamorphic and plutonic rocks; hydrothermal veins; skarns and sedimentary deposits. Details of the localities and mode of occurrence of smoky quartz, amethyst, milky quartz, rock crystal, rose quartz, citrine, agate and jasper are then given. -S.J.Stone

  18. Occurrence reporting and processing of operations information

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-21

    DOE O 232.1A, Occurrence Reporting and Processing of Operations Information, and 10 CFR 830.350, Occurrence Reporting and Processing of Operations Information (when it becomes effective), along with this manual, set forth occurrence reporting requirements for Department of Energy (DOE) Departmental Elements and contractors responsible for the management and operation of DOE-owned and -leased facilities. These requirements include categorization of occurrences related to safety, security, environment, health, or operations (``Reportable Occurrences``); DOE notification of these occurrences; and the development and submission of documented follow-up reports. This Manual provides detailed information for categorizing and reporting occurrences at DOE facilities. Information gathered by the Occurrence Reporting and processing System is used for analysis of the Department`s performance in environmental protection, safeguards and security, and safety and health of its workers and the public. This information is also used to develop lessons learned and document events that significantly impact DOE operations.

  19. Occurrence reporting and processing of operations information

    International Nuclear Information System (INIS)

    1997-01-01

    DOE O 232.1A, Occurrence Reporting and Processing of Operations Information, and 10 CFR 830.350, Occurrence Reporting and Processing of Operations Information (when it becomes effective), along with this manual, set forth occurrence reporting requirements for Department of Energy (DOE) Departmental Elements and contractors responsible for the management and operation of DOE-owned and -leased facilities. These requirements include categorization of occurrences related to safety, security, environment, health, or operations (''Reportable Occurrences''); DOE notification of these occurrences; and the development and submission of documented follow-up reports. This Manual provides detailed information for categorizing and reporting occurrences at DOE facilities. Information gathered by the Occurrence Reporting and processing System is used for analysis of the Department's performance in environmental protection, safeguards and security, and safety and health of its workers and the public. This information is also used to develop lessons learned and document events that significantly impact DOE operations

  20. Missed diagnosis-persistent delirium

    Directory of Open Access Journals (Sweden)

    Aseem Mehra

    2014-01-01

    Full Text Available Delirium is in general considered as an acute short lasting reversible neuropsychiatric syndrome. However, there is some evidence to suggest that in a small proportion of cases delirium may be a chronic or persistent condition. However, making this diagnosis requires clinical suspicion and ruling other differential diagnosis. In this report, we present a case of a 55-year-old man who had cognitive symptoms, psychotic symptoms and depressive symptoms along with persistent hypokalemia and glucose intolerance. He was seen by 3 psychiatrists with these symptoms and was initially diagnosed as having depressive disorder and later diagnosis of bipolar affective disorder (current episode mania, and psychosis were considered by the third psychiatrist. However, despite the presence of persistent neurocognitive deficits, evening worsening of symptoms, hypokalemia and glucose intolerance diagnosis of delirium was not suspected.

  1. Energy Savings Lifetimes and Persistence

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, Ian M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schiller, Steven R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Todd, Annika [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Billingsley, Megan A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goldman, Charles A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schwartz, Lisa C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-02-01

    This technical brief explains the concepts of energy savings lifetimes and savings persistence and discusses how program administrators use these factors to calculate savings for efficiency measures, programs and portfolios. Savings lifetime is the length of time that one or more energy efficiency measures or activities save energy, and savings persistence is the change in savings throughout the functional life of a given efficiency measure or activity. Savings lifetimes are essential for assessing the lifecycle benefits and cost effectiveness of efficiency activities and for forecasting loads in resource planning. The brief also provides estimates of savings lifetimes derived from a national collection of costs and savings for electric efficiency programs and portfolios.

  2. Persistence of Antarctic polar stratospheric clouds

    Science.gov (United States)

    Mccormick, M. Patrick; Trepte, C. R.

    1988-01-01

    The persistence of Polar Stratospheric Clouds (PSCs) observed by the Stratospheric Aerosol Measurement (SAM) 2 satellite sensor over a 9-year period is compared and contrasted. Histograms of the SAM 2 1.0 micron extinction ratio data (aerosol extinction normalized by the molecular extinction) at an altitude of 18 km in the Antarctic have been generated for three 10-day periods in the month of September. Statistics for eight different years (1979 to 1982 and 1984 to 1987) are shown in separate panels for each figure. Since the SAM 2 system is a solar occultation experiment, observations are limited to the edge of the polar night and no measurements are made deep within the vortex where temperatures could be colder. For this reason, use is made of the NMC global gridded fields and the known temperature-extinction relationship to infer additional information on the occurrence and areal coverage of PSCs. Calculations of the daily areal coverage of the 195 K isotherm will be presented for this same period of data. This contour level lies in the range of the predicted temperature for onset of the Type 1 particle enhancement mode at 50 mb (Poole and McCormick, 1988b) and should indicate approximately when formation of the binary HNO3-H2O particles begins.

  3. China's water pollution by persistent organic pollutants.

    Science.gov (United States)

    Bao, Lian-Jun; Maruya, Keith A; Snyder, Shane A; Zeng, Eddy Y

    2012-04-01

    Available data were reviewed to assess the status of contamination by persistent organic pollutants (POPs), including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), in drinking water sources and coastal waters of China. The levels of POPs in China's waters were generally at the high end of the global range. A comparison of China's regulatory limits indicated that PCBs in rivers and coastal water may pose potential human health risk. Occurrence of DDTs in some rivers of China may also pose health risk to humans using the regulatory limits of DDTs recommended by the European Union. Future monitoring of POPs in China's waters should be directed towards analytes of concern (e.g. PCBs and PCDD/Fs) and to fill data gaps for analytes (e.g. PBDEs, PCDD/Fs, and chlordane) and in watersheds/regions (e.g. West China) where data are scarce. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Persistence Mechanisms of Conjugative Plasmids

    DEFF Research Database (Denmark)

    Bahl, Martin Iain; Hansen, Lars H.; Sørensen, Søren Johannes

    2009-01-01

    Are plasmids selfish parasitic DNA molecules or an integrated part of the bacterial genome? This chapter reviews the current understanding of the persistence mechanisms of conjugative plasmids harbored by bacterial cells and populations. The diversity and intricacy of mechanisms affecting the suc...

  5. On persistently positively expansive maps

    Directory of Open Access Journals (Sweden)

    Alexander Arbieto

    2010-06-01

    Full Text Available In this paper, we prove that any C¹-persistently positively expansive map is expanding. This improves a result due to Sakai (Sakai 2004.Neste artigo, mostramos que todo mapa C¹-persistentemente positivamente expansivo e expansor. Isto melhora um resultado devido a Sakai (Sakai 2004.

  6. Atmospheric circulation associated with extreme generalized frosts persistence in central-southern South America

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Gabriela V. [Centro de Investigaciones Cientificas y Transferencia de Tecnologia a la Produccion, Diamante (CICYTTTP-CONICET), Diamante, Entre Rios (Argentina); Berri, Guillermo J. [Servicio Meteorologico Nacional - CONICET, Buenos Aires (Argentina)

    2012-03-15

    Generalized frosts (GF) in central-southern South America have a strong impact due to their spatial extension, and they are especially important when they become persistent. This paper aims at identifying the atmospheric circulation features that determine the extreme GF persistence, i.e. very persistent and without persistence, and the differences between them, during the 1961-1990 winters. Since the GF without persistence group outnumbers the other one, two subgroups are composed with events selected from winters with maximum and minimum frequency of GF occurrence, respectively. Additionally, the individual event of July 1988 within the very persistent GF group is analyzed due to its exceptional persistence. GF persistence is mainly conditioned by two large-scale dynamic factors. One is the Rossby wave train propagation across the Pacific Ocean, and the other one is the location with respect to the continent and the magnitude of the confluence in the jet entrance region in subtropical latitudes. A predominantly meridional Rossby wave train propagation with a confluence region to the west of the continent prior to the event favors GF with intermediate (null) persistence depending on the greater (lesser) jet acceleration. This is conditioned by the magnitude of the confluence, which, in turn, depends on the disposition of the wave train propagation pattern. Instead, an essentially zonal propagation with a confluence region to the east of the continent favors the GF persistence for several days, yet if there is no confluence the event does not persist. The greatest persistence of an event combines the confluence/diffluence of the jet entrance/exit region, which depends on the disposition with respect to the continent of the zonally propagating Rossby wave trains. (orig.)

  7. Persistence

    DEFF Research Database (Denmark)

    Hansen, Kis Boisen

    2012-01-01

    The note shows an example of an architure for buildin g stand-alone program, where the programming language is object oriented and the databas system is a relational database system. Together with the notes is an example program.......The note shows an example of an architure for buildin g stand-alone program, where the programming language is object oriented and the databas system is a relational database system. Together with the notes is an example program....

  8. Polycyclic hydrocarbons - occurrence and determination

    International Nuclear Information System (INIS)

    Drzewicz, P.

    2007-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are a special group of atmospheric contaminants included in the persistent toxic substances (PTS) and also in the volatile organic compounds (VOC) groups. PAHs are present in the atmosphere and their origin can be due to anthropogenic activities. The main source of emission of PAH is the combustion of fossil fuels. Their specific characteristics, high volatility, mutagenic and carcinogenic power, easily transportable for long distances with the wind, make them important contaminants despite of the fact that they are present at very low concentrations. The report provides a review of main analytical methods applied in the determination of PAH in air. Special attention was devoted to heterocyclic PAH which contain one or more heteroatom (sulphur, oxygen, nitrogen) in the multiple-fused ring. The presence of heterocyclic PAH requires very complex, laborious and long lasting sample separation methods before analysis. In some cases, application of different temperature programs in gas chromatography allows to determine PAH and heterocyclic PAH in gaseous samples without sample pretreatment. Gas chromatography methods for the determination of PAH and heterocyclic PAH in the gas from combustion of light heating oil has been optimized. (author) [pl

  9. Impact of innate and environmental factors on wheezing persistence during childhood.

    Science.gov (United States)

    Just, Jocelyne; Belfar, Samira; Wanin, Stéphanie; Pribil, Céline; Grimfeld, Alain; Duru, Gérard

    2010-05-01

    Persistent asthma in adults starts often early in childhood and is associated with alterations in respiratory function that occur early in life. The aim of this study was to evaluate the importance of innate and environmental factors associated with occurrence of asthma during childhood in a population of recurrent wheezing infants followed prospectively. A cohort of infants less than 30 months old with recurrent wheezing was established in order to assess severity of respiratory symptoms and to look for the presence of atopy and environmental risk factors. At the age of 6 years, they were reevaluated with respect to remission or persistence of wheezing over the previous 12-month period. Data were available for 219 subjects aged 15 +/- 5 months. In 27% of the infants with recurrent wheeze, wheezing persisted until the age of 6 years. In multivariate analysis, stepwise logit analysis showed that the risk factors for persistent wheezing are eosinophilia >or=470/mm(3), allergenic sensitization, and a father with asthma. Environmental factors present during the first year of life that protect from persistence of wheezing are ( 1 ) breastfeeding for longer than 3 months, ( 2 ) pets at home, and ( 3 ) >or=3 siblings. The detection rate for persistent wheezing in this model is 72%. The persistence score showed good specificity 91% but low sensitivity 35%. This study confirms the role of atopic host factors on wheezing persistence during childhood and detected protective environmental factors.

  10. Search along persistent random walks

    International Nuclear Information System (INIS)

    Friedrich, Benjamin M

    2008-01-01

    Optimal search strategies and their implementations in biological systems are a subject of active research. Here we study a search problem which is motivated by the hunt of sperm cells for the egg. We ask for the probability for an active swimmer to find a target under the condition that the swimmer starts at a certain distance from the target. We find that success probability is maximal for a certain level of fluctuations characterized by the persistence length of the swimming path of the swimmer. We derive a scaling law for the optimal persistence length as a function of the initial target distance and search time by mapping the search on a polymer physics problem

  11. Is Farm Management Skill Persistent?

    OpenAIRE

    Li, Xin; Paulson, Nicholas

    2014-01-01

    Farm management skills can affect farm managers' performance. In this article, farm management performance is analyzed based on yearly Illinois Farm Business Farm Management (FBFM) panel data across 6,760 farms from 1996 through 2011. Two out-of-sample measures of skill are used to analyze the ability of farm managers that consistently perform well over yearly and longer time horizons. Persistence tests show management skills are consistent and predictable. Results also suggest that the most ...

  12. Persistent Authentication in Smart Environments

    DEFF Research Database (Denmark)

    Hansen, Mads Syska; Kirschmeyer, Martin; Jensen, Christian D.

    2008-01-01

    present a proof-of-concept implementation of the proposed mechanism, which employs camera based tracking with a single stationary 3D camera that uses the "time of flight" principle. A preliminary evaluation of the proposed mechanism indicates that persistent authentication is technically possible...... with the proposed hardware. The proposed model is sufficiently general to allow the addition of more cameras or supplemental tracking technologies, which will improve the robustness and scalability of the proposed mechanism....

  13. Long memory and changing persistence

    DEFF Research Database (Denmark)

    Kruse, Robinson; Sibbertsen, Philipp

    We study the empirical behaviour of semi-parametric log-periodogram estimation for long memory models when the true process exhibits a change in persistence. Simulation results confirm theoretical arguments which suggest that evidence for long memory is likely to be found. A recently proposed test...... by Sibbertsen and Kruse (2009) is shown to exhibit noticeable power to discriminate between long memory and a structural change in autoregressive parameters....

  14. How persistent is civilization growth?

    OpenAIRE

    Garrett, Timothy J.

    2011-01-01

    In a recent study (Garrett, 2011), I described theoretical arguments and empirical evidence showing how civilization evolution might be considered from a purely physical basis. One implication is that civilization exhibits the property of persistence in its growth. Here, this argument is elaborated further, and specific near-term forecasts are provided for key economic variables and anthropogenic CO2 emission rates at global scales. Absent some external shock, civilization wealth, energy cons...

  15. Foreshock occurrence before large earthquakes

    Science.gov (United States)

    Reasenberg, P.A.

    1999-01-01

    Rates of foreshock occurrence involving shallow M ??? 6 and M ??? 7 mainshocks and M ??? 5 foreshocks were measured in two worldwide catalogs over ???20-year intervals. The overall rates observed are similar to ones measured in previous worldwide and regional studies when they are normalized for the ranges of magnitude difference they each span. The observed worldwide rates were compared to a generic model of earthquake clustering based on patterns of small and moderate aftershocks in California. The aftershock model was extended to the case of moderate foreshocks preceding large mainshocks. Overall, the observed worldwide foreshock rates exceed the extended California generic model by a factor of ???2. Significant differences in foreshock rate were found among subsets of earthquakes defined by their focal mechanism and tectonic region, with the rate before thrust events higher and the rate before strike-slip events lower than the worldwide average. Among the thrust events, a large majority, composed of events located in shallow subduction zones, had a high foreshock rate, while a minority, located in continental thrust belts, had a low rate. These differences may explain why previous surveys have found low foreshock rates among thrust events in California (especially southern California), while the worldwide observations suggests the opposite: California, lacking an active subduction zone in most of its territory, and including a region of mountain-building thrusts in the south, reflects the low rate apparently typical for continental thrusts, while the worldwide observations, dominated by shallow subduction zone events, are foreshock-rich. If this is so, then the California generic model may significantly underestimate the conditional probability for a very large (M ??? 8) earthquake following a potential (M ??? 7) foreshock in Cascadia. The magnitude differences among the identified foreshock-mainshock pairs in the Harvard catalog are consistent with a uniform

  16. The role of metabolism in bacterial persistence

    Directory of Open Access Journals (Sweden)

    Stephanie M. Amato

    2014-03-01

    Full Text Available Bacterial persisters are phenotypic variants with extraordinary tolerances toward antibiotics. Persister survival has been attributed to inhibition of essential cell functions during antibiotic stress, followed by reversal of the process and resumption of growth upon removal of the antibiotic. Metabolism plays a critical role in this process, since it participates in the entry, maintenance, and exit from the persister phenotype. Here, we review the experimental evidence that demonstrates the importance of metabolism to persistence, highlight the successes and potential for targeting metabolism in the search for anti-persister therapies, and discuss the current methods and challenges to understand persister physiology.

  17. The occurrence of a branchial cleft cyst in the anterior mediastinum: a case report

    International Nuclear Information System (INIS)

    Park, Seong Hoon; Kim, Seong Hoon; Shin, Hyun Woong; Jo, Hyun Chul; Son, Mi Yung; Gong, Joon Hyuk

    2008-01-01

    Branchial cleft cysts and branchial anomalies develop from the branchial cleft apparatus that persists after fetal development. The most common anatomical site for the occurrence of branchial cleft cysts is in the cervical area, generally anterior to the sternomastoid muscle in the upper or middle portion of the neck. A mediastinal branchial cleft cyst is extremely rare and few cases have been reported. We report the case of branchial cleft cyst found in the anterior mediastinum with literature review

  18. The occurrence of a branchial cleft cyst in the anterior mediastinum: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seong Hoon; Kim, Seong Hoon; Shin, Hyun Woong; Jo, Hyun Chul; Son, Mi Yung; Gong, Joon Hyuk [Daegu Fatima Hospital, Daegu (Korea, Republic of)

    2008-08-15

    Branchial cleft cysts and branchial anomalies develop from the branchial cleft apparatus that persists after fetal development. The most common anatomical site for the occurrence of branchial cleft cysts is in the cervical area, generally anterior to the sternomastoid muscle in the upper or middle portion of the neck. A mediastinal branchial cleft cyst is extremely rare and few cases have been reported. We report the case of branchial cleft cyst found in the anterior mediastinum with literature review.

  19. Patch size but not short-term isolation influences occurrence of westslope cutthroat trout above human-made barriers

    Science.gov (United States)

    Douglas P. Peterson; Bruce E. Rieman; Dona L. Horan; Michael K. Young

    2014-01-01

    Habitat fragmentation in aquatic systems has led to widespread isolation of stream fishes. Metapopulation theory predicts that persistence is directly related to local patch size and its characteristics, but because these relationships tend to be taxon-specific, empirical data are important. We assembled 246 observations of occurrence of westslope cutthroat trout (WCT...

  20. UMTRA project list of reportable occurrences

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    This UMTRA Project List of Reportable occurrences is provided to facilitate efficient categorization of reportable occurrences. These guidelines have been established in compliance with DOE minimum reporting requirements under DOE Order 5000.3B. Occurrences are arranged into nine groups relating to US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project operations for active sites. These nine groupings are provided for reference to determined whether an occurrence meets reporting requirement criteria in accordance with the minimum reporting requirements. Event groups and significance categories that cannot or will not occur, and that do not apply to UMTRA Project operations, are omitted. Occurrence categorization shall be as follows: Group 1. Facility Condition; Group 2. Environmental; Group 3. Personnel Safety; Group 4. Personnel Radiation Protection; Group 5. Safeguards and Security; Group 6. Transportation; Group 7. Value Basis Reporting; Group 8. Facility Status; and Group 9. Cross-Category Items.

  1. Report to Congress on abnormal occurrences

    International Nuclear Information System (INIS)

    1990-10-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from April 1 through June 30, 1990. The report discusses six abnormal occurrences, none involving a nuclear power plant. There were five abnormal occurrences at NRC licensees: (1) deficiencies in brachytherapy program; (2) a radiation overexposure of a radiographer; (3) a medical diagnostic misadministration; (4) administration of iodine-131 to a lactating female with subsequent uptake by her infant; and (5) a medical therapy misadministration. An Agreement State (Arizona) reported an abnormal occurrence involving a medical diagnostic misadministration. The report also contains information that updates a previously reported occurrence

  2. Report to Congress on abnormal occurrences

    International Nuclear Information System (INIS)

    1993-06-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health and safety and requires a quarterly report of such events to be made to Congress. This report covers the period January through March 1993. There is one abnormal occurrence at a nuclear power plant disposed in this report that involved a steam generator tube rupture at Palo Verde Unit 2, and none for fuel cycle facilities. Three abnormal occurrences involving medical misadminstrations (two therapeutic and one diagnostic) at NRC-licensed facilities are also discussed in this report. No abnormal occurrences were reported by NRC's Agreement States. The report also contains information updating previously reported abnormal occurrences

  3. UMTRA project list of reportable occurrences

    International Nuclear Information System (INIS)

    1994-04-01

    This UMTRA Project List of Reportable occurrences is provided to facilitate efficient categorization of reportable occurrences. These guidelines have been established in compliance with DOE minimum reporting requirements under DOE Order 5000.3B. Occurrences are arranged into nine groups relating to US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project operations for active sites. These nine groupings are provided for reference to determined whether an occurrence meets reporting requirement criteria in accordance with the minimum reporting requirements. Event groups and significance categories that cannot or will not occur, and that do not apply to UMTRA Project operations, are omitted. Occurrence categorization shall be as follows: Group 1. Facility Condition; Group 2. Environmental; Group 3. Personnel Safety; Group 4. Personnel Radiation Protection; Group 5. Safeguards and Security; Group 6. Transportation; Group 7. Value Basis Reporting; Group 8. Facility Status; and Group 9. Cross-Category Items

  4. RadCon Occurrence Reporting Simplified

    International Nuclear Information System (INIS)

    Denham, D. H.

    1999-01-01

    This narrative and accompanying diagrams provide a simplified summary of the RadCon Occurrence Reporting criteria to allow Environmental Restoration Contractor (ERC) staff to efficiently recognize occurrences and to effectively initiate the implementation of the requirements of U.S. Department of Energy (DOE) Order 232.1A, Occurrence Reporting and Processing of Operations Information, and of the ERC criteria defined in BHI-MA-02, ERC Project Procedures, Procedure 2.6, ''Occurrence Investigation and Reporting.'' These directives promote timely identification, categorization, notification, and reporting to DOE and ERC management of reportable occurrences at DOE-owned or -operated facilities that could (1) affect health and safety of the public, (2) seriously impact the intended purpose of DOE facilities, (3) adversely affect the credibility of DOE, or (4) have a noticeable adverse effect on the environment

  5. MOOCs and Persistence: Definitions and Predictors

    Science.gov (United States)

    Evans, Brent J.; Baker, Rachel B.

    2016-01-01

    The chapter argues for redefining the term "persistence" as it relates to MOOCs and considers how different measures produce different results in the research; it closes with a review of research on persistence in MOOCs.

  6. Persistence and drug tolerance in pathogenic yeast

    DEFF Research Database (Denmark)

    Bojsen, Rasmus Kenneth; Regenberg, Birgitte; Folkesson, Sven Anders

    2017-01-01

    In this review, we briefly summarize the current understanding of how fungal pathogens can persist antifungal treatment without heritable resistance mutations by forming tolerant persister cells. Fungal infections tolerant to antifungal treatment have become a major medical problem. One mechanism...

  7. Occurrence, behavior and effects of nanoparticles in the environment

    International Nuclear Information System (INIS)

    Nowack, Bernd; Bucheli, Thomas D.

    2007-01-01

    The increasing use of engineered nanoparticles (NP) in industrial and household applications will very likely lead to the release of such materials into the environment. Assessing the risks of these NP in the environment requires an understanding of their mobility, reactivity, ecotoxicity and persistency. This review presents an overview of the classes of NP relevant to the environment and summarizes their formation, emission, occurrence and fate in the environment. The engineered NP are thereby compared to natural products such as soot and organic colloids. To date only few quantitative analytical techniques for measuring NP in natural systems are available, which results in a serious lack of information about their occurrence in the environment. Results from ecotoxicological studies show that certain NP have effects on organisms under environmental conditions, though mostly at elevated concentrations. The next step towards an assessment of the risks of NP in the environment should therefore be to estimate the exposure to the different NP. It is also important to notice that most NP in technical applications are functionalized and therefore studies using pristine NP may not be relevant for assessing the behavior of the NP actually used. - The behavior and the effects of natural and engineered nanoparticles in the environment are reviewed

  8. Physical trust-based persistent authentication

    DEFF Research Database (Denmark)

    Fujita, Masahiro; Jensen, Christian D.; Arimura, Shiori

    2015-01-01

    propose a new type of persistent authentication, called Persistent Authentication Based On physical Trust (PABOT). PABOT uses a context of “physical trust relationship” that is built by visual contact between users, and thus can offer a persistent authentication mechanism with better usability and higher...

  9. Distributed Persistent Identifiers System Design

    Directory of Open Access Journals (Sweden)

    Pavel Golodoniuc

    2017-06-01

    Full Text Available The need to identify both digital and physical objects is ubiquitous in our society. Past and present persistent identifier (PID systems, of which there is a great variety in terms of technical and social implementation, have evolved with the advent of the Internet, which has allowed for globally unique and globally resolvable identifiers. PID systems have, by in large, catered for identifier uniqueness, integrity, and persistence, regardless of the identifier’s application domain. Trustworthiness of these systems has been measured by the criteria first defined by Bütikofer (2009 and further elaborated by Golodoniuc 'et al'. (2016 and Car 'et al'. (2017. Since many PID systems have been largely conceived and developed by a single organisation they faced challenges for widespread adoption and, most importantly, the ability to survive change of technology. We believe that a cause of PID systems that were once successful fading away is the centralisation of support infrastructure – both organisational and computing and data storage systems. In this paper, we propose a PID system design that implements the pillars of a trustworthy system – ensuring identifiers’ independence of any particular technology or organisation, implementation of core PID system functions, separation from data delivery, and enabling the system to adapt for future change. We propose decentralisation at all levels — persistent identifiers and information objects registration, resolution, and data delivery — using Distributed Hash Tables and traditional peer-to-peer networks with information replication and caching mechanisms, thus eliminating the need for a central PID data store. This will increase overall system fault tolerance thus ensuring its trustworthiness. We also discuss important aspects of the distributed system’s governance, such as the notion of the authoritative source and data integrity

  10. Occurrence studies of intracranial tumours

    Energy Technology Data Exchange (ETDEWEB)

    Larjavaara, S.

    2011-07-01

    Intracranial tumours are a histopathologically heterogeneous group of tumours. This thesis focused on three types of intracranial tumours; gliomas, meningiomas and vestibular schwannomas (VS). The main objectives of the dissertation were to estimate the occurrence of intracranial tumours by different subtypes, and to assess the validity and completeness of the cancer registry data. The specific aims of the publications were to evaluate the validity of reported incidence rates of meningioma cases, to describe the trends of VS incidence in four Nordic countries, and to define the anatomic distribution of gliomas and to investigate their location in relation to mobile phone use. Completeness of meningioma registration was examined by comparing five separate sources of information, and by defining the frequencies of cases reported to the Finnish Cancer Registry (FCR). Incidence trends of VS were assessed in the four Nordic countries over a twenty-one-year period (1987 - 2007) using cancer registry data. The anatomic site of gliomas was evaluated using both crude locations in the cerebral lobes and, in more detail, a three-dimensional (3D) distribution in the brain. In addition, a study on specific locations of gliomas in relation to the typical position of mobile phones was conducted using two separate approaches: a case-case and a case-specular analysis. The thesis was based on four sets of materials. Data from the international Interphone study were used for the studies on gliomas, while the two other studies were register-based. The dataset for meningiomas included meningioma cases from the FCR and four clinical data sources in Tampere University Hospital (neurosurgical clinic, pathology database, hospital discharge register and autopsy register). The data on VS were obtained from the national cancer registries of Denmark, Finland, Norway and Sweden. The coverage of meningiomas was not comprehensive in any of the data sources. The completeness of FCR was

  11. New-found fundamentals of bacterial persistence.

    Science.gov (United States)

    Kint, Cyrielle I; Verstraeten, Natalie; Fauvart, Maarten; Michiels, Jan

    2012-12-01

    Persister cells display tolerance to high doses of bactericidal antibiotics and typically comprise a small fraction of a bacterial population. Recently, evidence was provided for a causal link between therapy failure and the presence of persister cells in chronic infections, underscoring the need for research on bacterial persistence. A series of recent breakthroughs have shed light on the multiplicity of persister genes, the contribution of gene expression noise to persister formation, the importance of active responses to antibiotic tolerance and heterogeneity among persister cells. Moreover, the development of in vivo model systems has highlighted the clinical relevance of persistence. This review discusses these recent advances and how this knowledge fundamentally changes the way in which we will perceive the problem of antibiotic tolerance in years to come. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Occurrence of pneumomediastinum due to dental procedures.

    Science.gov (United States)

    Aslaner, Mehmet Ali; Kasap, Gül Nihal; Demir, Cihat; Akkaş, Meltem; Aksu, Nalan M

    2015-01-01

    The occurrence of pneumomediastinum and massive subcutaneous emphysema due to dental procedures is quite rare. We present a case of pneumomediastinum and massive subcutaneous emphysema that occurred during third molar tooth extraction with air-turbine handpiece.

  13. The Occurrence of Heamoproteuscolumbae in Pigeons ...

    African Journals Online (AJOL)

    The Occurrence of Heamoproteuscolumbae in Pigeons ( Columbidaelivia ) Based on Microscopy and PCR Based Method Analysis and Identification of New Lineage in the MalAvi Data Base in Kano State, Nigeria.

  14. Occurrence and distribution of Indian primates

    Science.gov (United States)

    Karanth, K.K.; Nichols, J.D.; Hines, J.E.

    2010-01-01

    Global and regional species conservation efforts are hindered by poor distribution data and range maps. Many Indian primates face extinction, but assessments of population status are hindered by lack of reliable distribution data. We estimated the current occurrence and distribution of 15 Indian primates by applying occupancy models to field data from a country-wide survey of local experts. We modeled species occurrence in relation to ecological and social covariates (protected areas, landscape characteristics, and human influences), which we believe are critical to determining species occurrence in India. We found evidence that protected areas positively influence occurrence of seven species and for some species are their only refuge. We found evergreen forests to be more critical for some primates along with temperate and deciduous forests. Elevation negatively influenced occurrence of three species. Lower human population density was positively associated with occurrence of five species, and higher cultural tolerance was positively associated with occurrence of three species. We find that 11 primates occupy less than 15% of the total land area of India. Vulnerable primates with restricted ranges are Golden langur, Arunachal macaque, Pig-tailed macaque, stump-tailed macaque, Phayre's leaf monkey, Nilgiri langur and Lion-tailed macaque. Only Hanuman langur and rhesus macaque are widely distributed. We find occupancy modeling to be useful in determining species ranges, and in agreement with current species ranking and IUCN status. In landscapes where monitoring efforts require optimizing cost, effort and time, we used ecological and social covariates to reliably estimate species occurrence and focus species conservation efforts. ?? Elsevier Ltd.

  15. Persistent cough in an adolescent.

    Science.gov (United States)

    Stein, M T; Harper, G; Chen, J

    1999-12-01

    Jessica, a 14-year-old girl with a history of asthma, went to her pediatrician's office because of a persistent cough. She had been coughing for at least 3 months with occasional cough-free periods of less than a few days. The cough was nonproductive and was not accompanied by fever, rhinorrhea, or facial or chest pain. Jessica and her mother observed that the cough increased with exercise and typically was not present during sleep. She has used two metered-dose inhalers--albuterol and cromolyn--without any change in the cough pattern. For the past 5 years, Jessica has had mild asthma responsive to albuterol. She enjoys running on the cross-country team, soccer, and dancing. She is an average student and denies any change in academic performance. She has never been hospitalized or had an emergency department visit for asthma or pneumonia. There has been no recent travel or exposure to a person with a chronic productive cough, tobacco smoke, or a live-in pet. Jessica lives with her mother and younger sister in a 10-year-old, carpeted apartment without any evidence of mold or recent renovation. In the process of taking the history, the pediatrician noticed that Jessica coughed intermittently, with two or three coughs during each episode. At times, the cough was harsh; at other times, it was a quiet cough, as if she were clearing her throat. She was cooperative, without overt anxiety or respiratory distress. After a complete physical examination with normal findings, the pediatrician interviewed Jessica and her mother alone. Jessica's parents had been divorced for the past 6 years. She lived with her mother but visited her father, and his new family with two young children, every weekend. She spoke about this arrangement comfortably and said that she loved her father and mother but didn't like the tension she experienced at her father's home. "I don't like adults arguing when kids are around." When asked why she thought the cough persisted so long, she commented in a

  16. The 'time of occurrence' in quantum mechanics

    International Nuclear Information System (INIS)

    Srinivas, M.D.; Vijayalakshmi, R.

    1981-01-01

    Apart from serving as a parameter in describing the evolution of a system, time appears also as an observable property of a system in experiments where one measures 'the time of occurrence' of an event associated with the system. However, while the observables normally encountered in quantum theory (and characterized by self-adjoint operators or projection-valued measures) correspond to instantaneous measurements, a time of occurrence measurement involves continuous observations being performed on the system to monitor when the event occurs. It is argued that a time of occurrence observable should be represented by a positive-operator-valued measure on the interval over which the experiment is carried out. It is shown that while the requirement of time-translation invariance and the spectral condition rule out the possibility of a self-adjoint time operator (Pauli's theorem), they do allow for time of occurrence observables to be represented by suitable positive-operator-valued measures. It is also shown that the uncertainty in the time of occurrence of an event satisfies the time-energy uncertainty relation as a consequence of the time-translation invariance, only if the time of occurrence experiment is performed on the entire time axis. (author)

  17. Persistent homology and string vacua

    Energy Technology Data Exchange (ETDEWEB)

    Cirafici, Michele [Center for Mathematical Analysis, Geometry and Dynamical Systems,Instituto Superior Técnico, Universidade de Lisboa,Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Institut des Hautes Études Scientifiques,Le Bois-Marie, 35 route de Chartres, F-91440 Bures-sur-Yvette (France)

    2016-03-08

    We use methods from topological data analysis to study the topological features of certain distributions of string vacua. Topological data analysis is a multi-scale approach used to analyze the topological features of a dataset by identifying which homological characteristics persist over a long range of scales. We apply these techniques in several contexts. We analyze N=2 vacua by focusing on certain distributions of Calabi-Yau varieties and Landau-Ginzburg models. We then turn to flux compactifications and discuss how we can use topological data analysis to extract physical information. Finally we apply these techniques to certain phenomenologically realistic heterotic models. We discuss the possibility of characterizing string vacua using the topological properties of their distributions.

  18. Coping with persistent environmental problems

    DEFF Research Database (Denmark)

    Varjopuro, Riku; Andrulewicz, Eugeniusz; Brandt, Urs Steiner

    2014-01-01

    to a decision to taking action and several years further for actual implementation. Ecosystem responses to measures illustrate that feedback can keep the ecosystem in a certain state and cause a delay in ecosystem response. These delays can operate on decadal scales. Our aim in this paper...... involved in the implementation are keys to improve understanding of the systemic delays. The improved understanding is necessary for the adaptive management of a persistent environmental problem. In addition to the state of the environment, the monitoring and analysis should be targeted also......; (2) implementation delay: the time from the launch of a policy to the actual implementation; (3) ecosystem delay: the time difference between the implementation and an actual measurable effects. A policy process is one characterized by delays. It may take years from problem identification...

  19. Bilateral persistent hyperplastic primary vitreous

    Directory of Open Access Journals (Sweden)

    Jain Tarun

    2009-01-01

    Full Text Available A case of bilateral persistent hyperplastic primary vitreous (PHPV in a 3-month-old male infant, who had bilateral leukokoria, is presented. The child was referred for imaging with a clinical suspicion of retinoblastoma. Gray-scale ultrasound evaluation revealed an echogenic band in the posterior segment of both globes, extending from the posterior surface of the lens capsule to the optic disc. Doppler examination revealed the presence of arterial flow in the band in both globes. Associated echogenic hemorrhage was also seen, which was confirmed by computed tomography. Most cases of PHPV are sporadic and unilateral, and bilateral PHPV is rare. The imaging features in this case suggest the diagnosis of bilateral PHPV and differentiate it from retinoblastoma. This entity, although infrequent, should be considered in the differential diagnosis while evaluating bilateral leukokoria.

  20. Persistence of antimuscarinic drug use

    DEFF Research Database (Denmark)

    Brostrøm, Søren; Hallas, Jesper

    2009-01-01

    PURPOSE: Evidence suggests antimuscarinic drugs for the overactive-bladder syndrome only confer modest improvements in quality of life. We wanted to describe the persistence of therapy, including an extended analysis beyond the 1-year follow-up employed in other studies. METHODS: All prescriptions...... for drugs in ATC category G04BD were retrieved for the period 1999-2006 from a regional database with complete capture of all reimbursed prescriptions. Kaplan-Meyer curves were generated for duration of treatment for each substance and analyzed for determinants of termination. RESULTS: With the exception...... of trospium chloride, all drugs had continuation rates of less than 50% at 6 months, less than 25% at 1 year, and less than 10% at 2 years and longer. Trospium chloride, however, exhibited continuation rates of 46% at 6 months, 36% at 1 year, 22% at 2 years, and 16% at 3 years. CONCLUSIONS: In a setting...

  1. Dematerialization: Variety, caution, and persistence.

    Science.gov (United States)

    Ausubel, Jesse H; Waggoner, Paul E

    2008-09-02

    Dematerialization, represented by declining consumption per GDP of energy or of goods, offers some hope for rising environmental quality with development. The declining proportion of income spent on staples as affluence grows, which income elasticity <1.0 measures, makes dematerialization widespread. Further, as learning improves efficiency of resource use, the intensity of environmental impact per production of staples often declines. We observe that combinations of low income elasticity for staples and of learning by producers cause a variety of dematerializations and declining intensities of impact, from energy use and carbon emission to food consumption and fertilizer use, globally and in countries ranging from the United States and France to China, India, Brazil, and Indonesia. Because dematerialization and intensity of impact are ratios of parameters that may be variously defined and are sometimes difficult to estimate, their fluctuations must be interpreted cautiously. Nevertheless, substantial declining intensity of impact, and especially, dematerialization persisted between 1980 and 2006.

  2. Work factors as predictors of persistent fatigue: a prospective study of nurses' aides.

    Science.gov (United States)

    Eriksen, W

    2006-06-01

    To identify work factors that predict persistent fatigue in nurses' aides. The sample comprised 5547 Norwegian nurses' aides, not on leave when they completed a mailed questionnaire in 1999. Of these, 4645 (83.7%) completed a second questionnaire 15 months later. The outcome measure was the occurrence of persistent fatigue, defined as having felt "usually fatigued" or "always fatigued" in daytime during the previous 14 days. In respondents without persistent fatigue at baseline, medium and high work demands, heavy smoking, being single, and having long term health problems were associated with increased risk of persistent fatigue at follow up. Medium and high rewards for well done work, medium levels of leadership fairness, and regular physical exercise were associated with reduced risk of persistent fatigue at follow up. In respondents with persistent fatigue at baseline, medium and high levels of positive challenges at work, high support from immediate superior, medium feedback about quality of one's work, and changes of work or work tasks that resulted in less heavy work or lower work pace were associated with increased odds of recovery (no persistent fatigue at follow up). Working in a nursing home and being intensely bothered by long term health problems were associated with reduced odds of recovery. High demands and lack of rewards at work may cause persistent fatigue in nurses' aides. Reduction of demands, adequate feedback, and mental stimulation in the form of support and positive challenges may facilitate recovery in those who have persistent fatigue. Leaders in the health services may be in a position to regulate factors that influence the level of fatigue in nurses' aides.

  3. Persistent low-grade inflammation and regular exercise

    DEFF Research Database (Denmark)

    Åström, Maj-brit; Feigh, Michael; Pedersen, Bente Klarlund

    2010-01-01

    against all of these diseases and recent evidence suggests that the protective effect of exercise may to some extent be ascribed to an anti-inflammatory effect of regular exercise. Visceral adiposity contributes to systemic inflammation and is independently associated with the occurrence of CVD, type 2...... diabetes and dementia. We suggest that the anti-inflammatory effects of exercise may be mediated via a long-term effect of exercise leading to a reduction in visceral fat mass and/or by induction of anti-inflammatory cytokines with each bout of exercise.......Persistent low-grade systemic inflammation is a feature of chronic diseases such as cardiovascular disease (CVD), type 2 diabetes and dementia and evidence exists that inflammation is a causal factor in the development of insulin resistance and atherosclerosis. Regular exercise offers protection...

  4. Persistent User Bias in Case-Crossover Studies in Pharmacoepidemiology

    DEFF Research Database (Denmark)

    Hallas, Jesper; Pottegård, Anton; Wang, Shirley

    2016-01-01

    Studying the effect of chronic medication exposure by means of a case-crossover design may result in an upward-biased odds ratio. In this study, our aim was to assess the occurrence of this bias and to evaluate whether it is remedied by including a control group (the case-time-control design...... for the retinal detachment controls were similar, leading to near-null case-time-control estimates for all 3 medication classes. For wrist fracture and stroke, the odds ratios were higher for cases than for controls, and case-time-control odds ratios were consistently above unity, thus implying significant...... residual bias. In case-crossover studies of medications, contamination by persistent users confers a moderate bias upward, which is partly remedied by using a control group. The optimal strategy for dealing with this problem is currently unknown....

  5. Persistence of stapedial artery: a case report

    International Nuclear Information System (INIS)

    Carvalho, Bruna Vilaca de; Gaiotti, Juliana Oggioni; Diniz, Renata Lopes Furletti Caldeira; Ribeiro, Marcelo Almeida; Motta, Emilia Guerra Pinto Coelho; Moreira, Wanderval

    2013-01-01

    Persistent stapedial artery is a rare congenital anomaly that occurs by a failure in the involution of such artery. Most patients with persistent stapedial artery are asymptomatic. The imaging diagnosis is made principally by means of multidetector computed tomography. In the present case, persistent stapedial artery was an incidental computed tomography finding. The authors discuss the embryogenesis, computed tomography findings and the importance of an early diagnosis of such anomaly. (author)

  6. Dualities in persistent (co)homology

    International Nuclear Information System (INIS)

    De Silva, Vin; Morozov, Dmitriy; Vejdemo-Johansson, Mikael

    2011-01-01

    We consider sequences of absolute and relative homology and cohomology groups that arise naturally for a filtered cell complex. We establish algebraic relationships between their persistence modules, and show that they contain equivalent information. We explain how one can use the existing algorithm for persistent homology to process any of the four modules, and relate it to a recently introduced persistent cohomology algorithm. We present experimental evidence for the practical efficiency of the latter algorithm

  7. Diurnal and seasonal occurrence of polar patches

    Directory of Open Access Journals (Sweden)

    A. S. Rodger

    1996-05-01

    Full Text Available Analysis of the diurnal and seasonal variation of polar patches, as identified in two years of HF-radar data from Halley, Antarctica during a period near sunspot maximum, shows that there is a broad maximum in occurrence centred about magnetic noon, not local noon. There are minima in occurrence near midsummer and midwinter, with maxima in occurrence between equinox and winter. There are no significant correlations between the occurrence of polar patches and the corresponding hourly averages of the solar wind and IMF parameters, except that patches usually occur when the interplanetary magnetic field has a southward component. The results can be understood in terms of UT and seasonal differences in the plasma concentration being convected from the dayside ionosphere into the polar cap. In summer and winter the electron concentrations in the polar cap are high and low, respectively, but relatively unstructured. About equinox, a tongue of enhanced ionisation is convected into the polar cap; this tongue is then structured by the effects of the interplanetary magnetic field, but these Halley data cannot be used to separate the various competing mechanisms for patch formation. The observed diurnal and seasonal variation in the occurrence of polar patches are largely consistent with predictions of Sojka et al. (1994 when their results are translated into the southern hemisphere. However, the ionospheric effects of flux transfer events are still considered essential in their formation, a feature not yet included in the Sojka et al. model.

  8. The Occurrence Rate of Hot Jupiters

    Science.gov (United States)

    Rampalli, Rayna; Catanzarite, Joseph; Batalha, Natalie M.

    2017-01-01

    As the first kind of exoplanet to be discovered, hot Jupiters have always been objects of interest. Despite being prevalent in radial velocity and ground-based surveys, they were found to be much rarer based on Kepler observations. These data show a pile-up at radii of 9-22 Rearth and orbital periods of 1-10 days. Computing accurate occurrence rates can lend insight into planet-formation and migration-theories. To get a more accurate look, the idea of reliability was introduced. Each hot Jupiter candidate was assigned a reliability based on its location in the galactic plane and likelihood of being a false positive. Numbers were updated if ground-based follow-up indicated a candidate was indeed a false positive. These reliabilities were introduced into an occurrence rate calculation and yielded about a 12% decrease in occurrence rate for each period bin examined and a 25% decrease across all the bins. To get a better idea of the cause behind the pileup, occurrence rates based on parent stellar metallicity were calculated. As expected from previous work, higher metallicity stars yield higher occurrence rates. Future work includes examining period distributions in both the high metallicity and low metallicity sample for a better understanding and confirmation of the pile-up effect.

  9. Drought Persistence Errors in Global Climate Models

    Science.gov (United States)

    Moon, H.; Gudmundsson, L.; Seneviratne, S. I.

    2018-04-01

    The persistence of drought events largely determines the severity of socioeconomic and ecological impacts, but the capability of current global climate models (GCMs) to simulate such events is subject to large uncertainties. In this study, the representation of drought persistence in GCMs is assessed by comparing state-of-the-art GCM model simulations to observation-based data sets. For doing so, we consider dry-to-dry transition probabilities at monthly and annual scales as estimates for drought persistence, where a dry status is defined as negative precipitation anomaly. Though there is a substantial spread in the drought persistence bias, most of the simulations show systematic underestimation of drought persistence at global scale. Subsequently, we analyzed to which degree (i) inaccurate observations, (ii) differences among models, (iii) internal climate variability, and (iv) uncertainty of the employed statistical methods contribute to the spread in drought persistence errors using an analysis of variance approach. The results show that at monthly scale, model uncertainty and observational uncertainty dominate, while the contribution from internal variability is small in most cases. At annual scale, the spread of the drought persistence error is dominated by the statistical estimation error of drought persistence, indicating that the partitioning of the error is impaired by the limited number of considered time steps. These findings reveal systematic errors in the representation of drought persistence in current GCMs and suggest directions for further model improvement.

  10. Translating Romans: some persistent headaches

    Directory of Open Access Journals (Sweden)

    A.B. du Toit

    2010-07-01

    Full Text Available Translating Romans: some persistent headaches Gone are the days when it was axiomatic that expertise in biblical languages automatically qualified one as a Bible translator. In 1949, Ronald Knox, who for nine years conscientiously struggled with translating the Bible for his generation, published a booklet under the title The trials of a translator. At that stage Bible translation as the subject of scientific study was still in its infancy. Since then, research into the intricacies of communicating the biblical message in an authentic but understandable manner, has made significant progress (cf. Roberts, 2009. However, the frustrations of Bible translators, first of all to really understand what the biblical authors wanted to convey to their original addressees, and then to commu-nicate that message to their own targeted readers in a meaningful way, have not disappeared. In fact, the challenge to meet the vary-ing requirements of the multiple kinds of translation that are present-ly in vogue, has only increased.

  11. Energy savings: persuasion and persistence

    Energy Technology Data Exchange (ETDEWEB)

    Eijadi, David; McDougall, Tom; Leaf, Kris; Douglas, Jim; Steinbock, Jason; Reimer, Paul [The Weidt Group, Minnetonka, MN (United States); Gauthier, Julia [Xcel Energy, Minneapolis, MN (United States); Wild, Doug; Richards McDaniel, Stephanie [BWBR Architects, Inc., Saint Paul, MN (United States)

    2005-07-01

    In this study, the architects, sponsoring utility and energy simulation specialist joined together to investigate the persistence of energy savings in three completed projects: a college library; a municipal transportation facility; and a hospital. The primary question being 'How well did the design decisions made with the help of simulation analysis translate into building operations over several years?' Design simulation and metered performance data are compared for specific energy-saving strategies. The paper provides a brief overview of the basis of selection of the three projects, the energy design assistance methods employed and the decisions made, along with their savings expectations. For each case, design characteristics, modelling assumptions, selected strategies and actual metered performance are outlined. We find evidence of appropriate levels of energy conservation, but they are not the absolute values predicted. In each case, the discrepancies between modelling assumptions and final construction or operating procedures are identified, examined and rectified. The paper illustrates that while owners are saving energy, they are not always getting the full savings potential for what they install. The paper concludes with a re-examination of the overall process. It evaluates the potential for additional savings of individual technologies and related larger utility incentives to design teams and building owners.

  12. Limitations in global information on species occurrences

    Directory of Open Access Journals (Sweden)

    Carsten Meyer

    2016-07-01

    Full Text Available Detailed information on species distributions is crucial for answering central questions in biogeography, ecology, evolutionary biology and conservation. Millions of species occurrence records have been mobilized via international data-sharing networks, but inherent biases, gaps and uncertainties hamper broader application. In my PhD thesis, I presented the first comprehensive analyses of global patterns and drivers of these limitations across different taxonomic groups and spatial scales. Integrating 300 million occurrence records for terrestrial vertebrates and plants with comprehensive taxonomic databases, expert range maps and regional checklists, I demonstrated extensive taxonomic, geographical and temporal biases, gaps and uncertainties. I identified key socio-economic drivers of data bias across different taxonomic groups and spatial scales. The results of my dissertation provide an empirical baseline for effectively accounting for data limitations in distribution models, as well as for prioritizing and monitoring efforts to collate additional occurrence information.

  13. Report on Congress on abnormal occurrences

    International Nuclear Information System (INIS)

    1991-06-01

    Section 208 of the energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from January 1 through March 31, 1991. The report discusses six abnormal occurrences, none of which involved a nuclear power plant. Five of the events occurred at NRC-licensed facilities: one involved a significant degradation of plant safety at a nuclear fuel cycle facility, one involved a medical diagnostic misadministration, and three involved medical therapy misadministrations. An Agreement State (Arizona) reported one abnormal occurrence that involved medical therapy misadministrations

  14. A persistent homology approach to collective behavior in insect swarms

    Science.gov (United States)

    Sinhuber, Michael; Ouellette, Nicholas T.

    Various animals from birds and fish to insects tend to form aggregates, displaying self-organized collective swarming behavior. Due to their frequent occurrence in nature and their implications for engineered, collective systems, these systems have been investigated and modeled thoroughly for decades. Common approaches range from modeling them with coupled differential equations on the individual level up to continuum approaches. We present an alternative, topology-based approach for describing swarming behavior at the macroscale rather than the microscale. We study laboratory swarms of Chironomus riparius, a flying, non-biting midge. To obtain the time-resolved three-dimensional trajectories of individual insects, we use a multi-camera stereoimaging and particle-tracking setup. To investigate the swarming behavior in a topological sense, we employ a persistent homology approach to identify persisting structures and features in the insect swarm that elude a direct, ensemble-averaging approach. We are able to identify features of sub-clusters in the swarm that show behavior distinct from that of the remaining swarm members. The coexistence of sub-swarms with different features resembles some non-biological systems such as active colloids or even thermodynamic systems.

  15. Co-occurrence of chancroid and gonorrhea.

    Science.gov (United States)

    Nawaf, Al-Mutairi; Joshi, Arun; Tayeh, Mohammad

    2006-01-01

    Gonorrhea and chancroid are common sexually transmitted infections in many parts of the world. Still, co-occurrence of these two conditions is uncommonly reported. We present here a patient who presented with painful genital ulcers and urethral discharge simultaneously acquired from a single exposure, which turned out to be chancroid and gonorrhea, respectively. Both conditions responded well to a single intramuscular dose of ceftriaxone 250 mg. This report describes the uncommon occurrence of gonorrhea and chancroid in a patient. Clinical features, relevant investigations, treatment options of these two sexually transmitted infections, and possible implications in view of the human immunodeficiency virus (HIV) pandemic are briefly discussed.

  16. Mastering NServiceBus and persistence

    CERN Document Server

    Helton, Rich

    2014-01-01

    This book is intended for developers, designers, and architects alike who wish to build C# NServiceBus enterprise architectures and learn how ESB persists data and messages to help them attain their goals. No prior knowledge of persistence in NServiceBus is required.

  17. Is bacterial persistence a social trait?

    Directory of Open Access Journals (Sweden)

    Andy Gardner

    Full Text Available The ability of bacteria to evolve resistance to antibiotics has been much reported in recent years. It is less well-known that within populations of bacteria there are cells which are resistant due to a non-inherited phenotypic switch to a slow-growing state. Although such 'persister' cells are receiving increasing attention, the evolutionary forces involved have been relatively ignored. Persistence has a direct benefit to cells because it allows survival during catastrophes-a form of bet-hedging. However, persistence can also provide an indirect benefit to other individuals, because the reduced growth rate can reduce competition for limiting resources. This raises the possibility that persistence is a social trait, which can be influenced by kin selection. We develop a theoretical model to investigate the social consequences of persistence. We predict that selection for persistence is increased when: (a cells are related (e.g. a single, clonal lineage; and (b resources are scarce. Our model allows us to predict how the level of persistence should vary with time, across populations, in response to intervention strategies and the level of competition. More generally, our results clarify the links between persistence and other bet-hedging or social behaviours.

  18. The Persistence of Mutual Fund Performance.

    OpenAIRE

    Grinblatt, Mark; Titman, Sheridan

    1992-01-01

    This paper analyzes how mutual fund performance relates to past performance. These tests are based on a multiple portfolio benchmark that was formed on the basis of securities characteristics. The authors find evidence that differences in performance between funds persist over time and that this persistence is consistent with the ability of fund managers to earn abnormal returns. Copyright 1992 by American Finance Association.

  19. Modelling asymmetric persistence over the business cycle

    NARCIS (Netherlands)

    Ph.H.B.F. Franses (Philip Hans); R. Paap (Richard)

    1998-01-01

    textabstractWe address the issue of time varying persistence of shocks to macroeconomic time series variables by proposing a new and parsimonious time series model. Our model assumes that this time varying persistence depends on a linear combination of lagged explanatory variables, where this

  20. A model for persistency of egg production

    NARCIS (Netherlands)

    Grossman, M.; Gossman, T.N.; Koops, W.J.

    2000-01-01

    The objectives of our study were to propose a new definition for persistency of egg production and to develop a mathematical model to describe the egg production curve, one that includes a new measure for persistency, based on the proposed definition, for use as a selection criterion to improve

  1. Lymphogranuloma venereum causing a persistent genital ulcer.

    Science.gov (United States)

    Marcotte, Terrence; Lee, Yer; Pandori, Mark; Jain, Vivek; Cohen, Stephanie Elise

    2014-04-01

    Lymphogranuloma venereum (LGV) is a sexually transmitted cause of inguinal lymphadenopathy and proctocolitis. We report a patient with a persistent genital ulcer due to LGV (serovar L2b), an unusual presentation among US men who have sex with men. Lymphogranuloma venereum should be considered when evaluating persistent genital ulcers, and LGV-specific testing should be sought.

  2. Persistent Identifiers as Boundary Objects

    Science.gov (United States)

    Parsons, M. A.; Fox, P. A.

    2017-12-01

    In 1989, Leigh Star and Jim Griesemer defined the seminal concept of `boundary objects'. These `objects' are what Latour calls `immutable mobiles' that enable communication and collaboration across difference by helping meaning to be understood in different contexts. As Star notes, they are a sort of arrangement that allow different groups to work together without (a priori) consensus. Part of the idea is to recognize and allow for the `interpretive flexibility' that is central to much of the `constructivist' approach in the sociology of science. Persistent Identifiers (PIDs) can clearly act as boundary objects, but people do not usually assume that they enable interpretive flexibility. After all, they are meant to be unambiguous, machine-interpretable identifiers of defined artifacts. In this paper, we argue that PIDs can fill at least two roles: 1) That of the standardized form, where there is strong agreement on what is being represented and how and 2) that of the idealized type, a more conceptual concept that allows many different representations. We further argue that these seemingly abstract conceptions actually help us implement PIDs more effectively to link data, publications, various other artifacts, and especially people. Considering PIDs as boundary objects can help us address issues such as what level of granularity is necessary for PIDs, what metadata should be directly associated with PIDs, and what purpose is the PID serving (reference, provenance, credit, etc.). In short, sociological theory can improve data sharing standards and their implementation in a way that enables broad interdisciplinary data sharing and reuse. We will illustrate this with several specific examples of Earth science data.

  3. Stochastic convergence of persistence landscapes and silhouettes

    Directory of Open Access Journals (Sweden)

    Frédéric Chazal

    2015-03-01

    Full Text Available Persistent homology is a widely used tool in Topological Data Analysis that encodes multi-scale topological information as a multiset of points in the plane called a persistence diagram. It is difficult to apply statistical theory directly to a random sample of diagrams. Instead, we summarize persistent homology with a persistence landscape, introduced by Bubenik, which converts a diagram into a well-behaved real-valued function. We investigate the statistical properties of landscapes, such as weak convergence of the average landscapes and convergence of the bootstrap. In addition, we introduce an alternate functional summary of persistent homology, which we call the silhouette, and derive an analogous statistical theory.

  4. On persistence interfaces for scientific data stores

    International Nuclear Information System (INIS)

    Malon, D.M.; May, E.N.

    1996-01-01

    A common dilemma among builders of large scientific data stores is whether to use a lightweight object persistence manager or a genuine object-oriented database. There are often good reasons to consider each of these strategies; a few are described in this paper. Too often, however, electing to use a lightweight approach has meant programming to an interface that is entirely different than that expected by commercial object-oriented databases. With the emergence of object database standards, it is possible to provide an interface to persistence managers that does not needlessly inhibit coexistence with (and, perhaps, eventual migration to) object-oriented databases. This paper describes an implementation of a substantial subset of the ODMG-93[1]C++ specification that allows clients to use many of today's lightweight object persistence managers through an interface that conforms to the ODMG standard. We also describe a minimal interface that persistence software should support in order to provide persistence services for ODMG implementations

  5. Persistence Characteristics of Australian Rainfall Anomalies

    Science.gov (United States)

    Simmonds, Ian; Hope, Pandora

    1997-05-01

    Using 79 years (1913-1991) of Australian monthly precipitation data we examined the nature of the persistence of rainfall anomalies. Analyses were performed for four climate regions covering the country, as well as for the entire Australian continent. We show that rainfall over these regions has high temporal variability and that annual rainfall amounts over all five sectors vary in phase and are, with the exception of the north-west region, significantly correlated with the Southern Oscillation Index (SOI). These relationships were particularly strong during the spring season.It is demonstrated that Australian rainfall exhibits statistically significant persistence on monthly, seasonal, and (to a limited extent) annual time-scales, up to lags of 3 months and one season and 1 year. The persistence showed strong seasonal dependence, with each of the five regions showing memory out to 4 or 5 months from winter and spring. Many aspects of climate in the Australasian region are known to have undergone considerable changes about 1950. We show this to be true for persistence also; its characteristics identified for the entire record were present during the 1951--1980 period, but virtually disappeared in the previous 30-year period.Much of the seasonal distribution of rainfall persistence on monthly time-scales, particularly in the east, is due to the influence of the SOI. However, most of the persistence identified in winter and spring in the north-west is independent of the ENSO phenomenon.Rainfall anomalies following extreme dry and wet months, seasons and years (lowest and highest two deciles) persisted more than would be expected by chance. For monthly extreme events this was more marked in the winter semester for the wet events, except in the south-east region. In general, less persistence was found for the extreme seasons. Although the persistence of dry years was less than would have been expected by chance, the wet years appear to display persistence.

  6. Active Longitude and Coronal Mass Ejection Occurrences

    International Nuclear Information System (INIS)

    Gyenge, N.; Kiss, T. S.; Erdélyi, R.; Singh, T.; Srivastava, A. K.

    2017-01-01

    The spatial inhomogeneity of the distribution of coronal mass ejection (CME) occurrences in the solar atmosphere could provide a tool to estimate the longitudinal position of the most probable CME-capable active regions in the Sun. The anomaly in the longitudinal distribution of active regions themselves is often referred to as active longitude (AL). In order to reveal the connection between the AL and CME spatial occurrences, here we investigate the morphological properties of active regions. The first morphological property studied is the separateness parameter, which is able to characterize the probability of the occurrence of an energetic event, such as a solar flare or CME. The second morphological property is the sunspot tilt angle. The tilt angle of sunspot groups allows us to estimate the helicity of active regions. The increased helicity leads to a more complex buildup of the magnetic structure and also can cause CME eruption. We found that the most complex active regions appear near the AL and that the AL itself is associated with the most tilted active regions. Therefore, the number of CME occurrences is higher within the AL. The origin of the fast CMEs is also found to be associated with this region. We concluded that the source of the most probably CME-capable active regions is at the AL. By applying this method, we can potentially forecast a flare and/or CME source several Carrington rotations in advance. This finding also provides new information for solar dynamo modeling.

  7. Active Longitude and Coronal Mass Ejection Occurrences

    Energy Technology Data Exchange (ETDEWEB)

    Gyenge, N.; Kiss, T. S.; Erdélyi, R. [Solar Physics and Space Plasmas Research Centre (SP2RC), School of Mathematics and Statistics, University of Sheffield Hounsfield Road, Hicks Building, Sheffield S3 7RH (United Kingdom); Singh, T.; Srivastava, A. K., E-mail: n.g.gyenge@sheffield.ac.uk [Department of Physics, Indian Institute of Technology (Banaras Hindu University), Varanasi (India)

    2017-03-20

    The spatial inhomogeneity of the distribution of coronal mass ejection (CME) occurrences in the solar atmosphere could provide a tool to estimate the longitudinal position of the most probable CME-capable active regions in the Sun. The anomaly in the longitudinal distribution of active regions themselves is often referred to as active longitude (AL). In order to reveal the connection between the AL and CME spatial occurrences, here we investigate the morphological properties of active regions. The first morphological property studied is the separateness parameter, which is able to characterize the probability of the occurrence of an energetic event, such as a solar flare or CME. The second morphological property is the sunspot tilt angle. The tilt angle of sunspot groups allows us to estimate the helicity of active regions. The increased helicity leads to a more complex buildup of the magnetic structure and also can cause CME eruption. We found that the most complex active regions appear near the AL and that the AL itself is associated with the most tilted active regions. Therefore, the number of CME occurrences is higher within the AL. The origin of the fast CMEs is also found to be associated with this region. We concluded that the source of the most probably CME-capable active regions is at the AL. By applying this method, we can potentially forecast a flare and/or CME source several Carrington rotations in advance. This finding also provides new information for solar dynamo modeling.

  8. Active Longitude and Coronal Mass Ejection Occurrences

    Science.gov (United States)

    Gyenge, N.; Singh, T.; Kiss, T. S.; Srivastava, A. K.; Erdélyi, R.

    2017-03-01

    The spatial inhomogeneity of the distribution of coronal mass ejection (CME) occurrences in the solar atmosphere could provide a tool to estimate the longitudinal position of the most probable CME-capable active regions in the Sun. The anomaly in the longitudinal distribution of active regions themselves is often referred to as active longitude (AL). In order to reveal the connection between the AL and CME spatial occurrences, here we investigate the morphological properties of active regions. The first morphological property studied is the separateness parameter, which is able to characterize the probability of the occurrence of an energetic event, such as a solar flare or CME. The second morphological property is the sunspot tilt angle. The tilt angle of sunspot groups allows us to estimate the helicity of active regions. The increased helicity leads to a more complex buildup of the magnetic structure and also can cause CME eruption. We found that the most complex active regions appear near the AL and that the AL itself is associated with the most tilted active regions. Therefore, the number of CME occurrences is higher within the AL. The origin of the fast CMEs is also found to be associated with this region. We concluded that the source of the most probably CME-capable active regions is at the AL. By applying this method, we can potentially forecast a flare and/or CME source several Carrington rotations in advance. This finding also provides new information for solar dynamo modeling.

  9. Familial occurrence of inflammatory bowel disease

    DEFF Research Database (Denmark)

    Orholm, M; Munkholm, P; Langholz, E

    1991-01-01

    BACKGROUND AND METHODS: We assessed the familial occurrence of inflammatory bowel disease in Copenhagen County, where there has been a long-term interest in the epidemiology of such disorders. In 1987 we interviewed 662 patients in whom inflammatory bowel disease had been diagnosed before 1979, a...

  10. A mathematical model for predicting earthquake occurrence ...

    African Journals Online (AJOL)

    We consider the continental crust under damage. We use the observed results of microseism in many seismic stations of the world which was established to study the time series of the activities of the continental crust with a view to predicting possible time of occurrence of earthquake. We consider microseism time series ...

  11. Occurrence and functioning of phosphate solubilizing ...

    African Journals Online (AJOL)

    Occurrence and functioning of phosphate solubilizing microorganisms from oil palm tree ( Elaeis guineensis ) rhizosphere in Cameroon. ... While the use of soluble mineral phosphate fertilizers is the obvious best means to combat phosphate ... in order to improve agricultural production, using low inputs technology. Isolates ...

  12. Phenotypic occurrence of methicillin-resistant Staphylococcus ...

    African Journals Online (AJOL)

    To assess the occurrence of MRSA among camels in Kano abattoir, a total of 300 nasal swabs were collected from camels at the lairage in Kano abattoir, Kano state, Nigeria to isolate and biochemically characterize Staphylococcus aureus and confirm methicillin-resistant Staphylococcus aureus among isolates using ...

  13. Occurrence of Wounds in Nigerian Horses.

    Science.gov (United States)

    Agina, Onyinyechukwu A; Ihedioha, John I

    2017-01-01

    This study investigated the occurrence of wounds in Nigerian horses. The study population was 1,621 horses sold at the Obollo Afor horse lairage in Enugu State, Nigeria, during a 6-month period: 3 months of dry season and 3 months of rainy season (February-April and June-August 2012). A total of 207 horses were systematically sampled and subjected to a comprehensive physical examination. Those with wounds were marked, recorded, and clinically examined. Of the 207 horses sampled, 21 (10.1%) had wounds. The body distribution of the wounds was 9.5% head, 9.5% forelimbs, 19.1% hind limbs, 4.8% tail, 14.3% flank, 9.5% loin, 19.1% hip, 9.5% barrel, and 4.8% croup. The occurrence of the wounds was not significantly associated with sex or season, but the occurrence in adults was significantly (p horses. It was concluded that the occurrence of wounds is relatively high (10.1%), and mainly the hind limbs, hip, and flank of adult horses are affected. It was recommended that horse guardians and handlers should be properly educated on the care of horses.

  14. Occurrence of Domatia as a systematic character

    NARCIS (Netherlands)

    Steenis, van C.G.G.J.

    1967-01-01

    In our Bulletin no 20, pp. 1272-1273, Dr. M. Jacobs made some notes on the nature and occurrence of domatia. His full paper has now appeared (Proc. Kon. Akad. Wet. A’dam C 69, 1966, 275-316, repr. 1-44) and this means to be a great step forward in the study of these peculiar structures, which are

  15. Occurrence and properties of Petunia peroxidase a

    NARCIS (Netherlands)

    Hendriks, T.

    1989-01-01

    Peroxidases are probably the most extensively studied enzymes in higher plants. Various isoenzymes occur as soluble proteins in the apoplast and in the vacuole, or are bound to membranes and cell walls. Their occurrence is often organ-specific and developmentally controlled, and there is

  16. Disability occurrence and proximity to death

    NARCIS (Netherlands)

    Klijs, Bart; Mackenbach, Johan P.; Kunst, Anton E.

    2010-01-01

    Purpose. This paper aims to assess whether disability occurrence is related more strongly to proximity to death than to age. Method. Self reported disability and vital status were available from six annual waves and a subsequent 12-year mortality follow-up of the Dutch GLOBE longitudinal study.

  17. CO-OCCURRENCE OF DIABETES AND HYPERTENSION ...

    African Journals Online (AJOL)

    cardiovascular disease (CVD), and when they co-exist ... and hypertension among patients with co-occurrence ... are any clinical and metabolic differences between those ... The last 3 readings of their fasting blood .... as insulin resistance, aging, obesity, use of thiazide ... therapy as risk factors for type 2 diabetes mellitus.

  18. Pyrrolizidine alkaloids: occurrence, biology, and chemical synthesis.

    Science.gov (United States)

    Robertson, Jeremy; Stevens, Kiri

    2017-01-04

    Covering: 2013 up to the end of 2015This review covers the isolation and structure of new pyrrolizidines; pyrrolizidine biosynthesis; biological activity, including the occurrence of pyrrolizidines as toxic components or contaminants in foods and beverages; and formal and total syntheses of naturally-occurring pyrrolizidine alkaloids and closely related non-natural analogues.

  19. [Occurrence of Prototheca mastitis in dairy farms in Hesse].

    Science.gov (United States)

    Schlenstedt, R; Zschöck, M; Kloppert, B; Wolter, W

    1997-08-01

    During January 1994 and August 1996 from dairy farms in Hessia a total of 305,609 milk samples were investigated. Prototheca sp. as etiological agent of a mastitis was isolated from milk samples of seven dairy herds. According to our experiences and to several reports from various countries dealing with Prototheca infections in dairy herds, mastitis control programs should include Prototheca algae as potential pathogens. Mastitis due to this organism usually occurs in different semeiologies, one with clinical symptoms, and the other, more common type, as subclinical mastitis. In both cases, Prototheca organisms use to persist in the tissue of the mammary gland also during the dry period and antimicrobial treatment proves to be ineffective. Considering the wide distribution of these algae as saprophytes in the environment and in feces of several domestic animals, predisposing factors like a humid aerobic milieu and unsanitary milking conditions are necessary for Prototheca infections becoming manifest in the udder of dairy cows. Control measures should preferably stress the identification and removal of infected animals, in particular when the disease is sporadic in the herd. Due to the more questionable occurrence of spontaneous healing and the lack of an efficient drug, slaughtering of infected cows appears as a suitable method to eliminate the disease from the herd. Additionally, improvement of the hygiene status concerning feeding and milking management within a herd is as essential as in the control of other opportunistic udder pathogens.

  20. Occurrence, distribution, and seasonality of emerging contaminants in urban watersheds.

    Science.gov (United States)

    Bai, Xuelian; Lutz, Alex; Carroll, Rosemary; Keteles, Kristen; Dahlin, Kenneth; Murphy, Mark; Nguyen, David

    2018-06-01

    The widespread occurrence of natural and synthetic organic chemicals in surface waters can cause ecological risks and human health concerns. This study measured a suite of contaminants of emerging concern (CECs) in water samples collected by the U.S. Environmental Protection Agency Region 8 around the Denver, Colorado, metropolitan area. The results showed that 109 of 144 analyzed pharmaceutical compounds, 42 of 55 analyzed waste-indicator compounds (e.g., flame retardants, hormones, and personal care products), and 39 of 72 analyzed pesticides were detected in the water samples collected monthly between April and November in both 2014 and 2015. Pharmaceutical compounds were most abundant in the surface waters and their median concentrations were measured up to a few hundred nanograms per liter. The CEC concentrations varied depending on sampling locations and seasons. The primary source of CECs was speculated to be wastewater effluent. The CEC concentrations were correlated to streamflow volume and showed significant seasonal effects. The CECs were less persistent during spring runoff season compared with baseflow season at most sampling sites. These results are useful for providing baseline data for surface CEC monitoring and assessing the environmental risks and potential human exposure to CECs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Antibiotics in the surface water of the Yangtze Estuary: occurrence, distribution and risk assessment.

    Science.gov (United States)

    Yan, Caixia; Yang, Yi; Zhou, Junliang; Liu, Min; Nie, Minghua; Shi, Hao; Gu, Lijun

    2013-04-01

    The occurrence and distribution of five groups of antibiotics were investigated in the surface water of Yangtze Estuary over four seasons. Of the 20 antibiotics, only sulfamerazine was not detected at all sampling sites, indicating widespread occurrence of antibiotic residues in the study area. Detection frequencies and concentrations of antibiotics were generally higher in January, indicating that low flow conditions and low temperature might enhance the persistence of antibiotics in water. Antibiotic levels varied with location, with the highest concentrations being observed around river discharge and sewage outfall. Furthermore, a positive correlation between total antibiotic and DOC concentrations revealed the significant role played by DOC. Risk assessment based on single compound exposure showed that sulfapyridine and sulfamethoxazole could cause medium risk to daphnid in the Yangtze Estuary. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Decreasing trend in severe weather occurrence over China during the past 50 years

    Science.gov (United States)

    Zhang, Qinghong; Ni, Xiang; Zhang, Fuqing

    2017-04-01

    Understanding the trend of localized severe weather under the changing climate is of great significance but remains challenging which is at least partially due to the lack of persistent and homogeneous severe weather observations at climate scales while the detailed physical processes of severe weather cannot be resolved in global climate models. Based on continuous and coherent severe weather reports from over 500 manned stations, for the first time, this study shows a significant decreasing trend in severe weather occurrence across China during the past five decades. The total number of severe weather days that have either thunderstorm, hail and/or damaging wind decrease about 50% from 1961 to 2010. It is further shown that the reduction in severe weather occurrences correlates strongly with the weakening of East Asian summer monsoon which is the primary source of moisture and dynamic forcing conducive for warm-season severe weather over China.

  3. Occurrence of Chiral Bioactive Compounds in the Aquatic Environment: A Review

    Directory of Open Access Journals (Sweden)

    Cláudia Ribeiro

    2017-10-01

    Full Text Available In recent decades, the presence of micropollutants in the environment has been extensively studied due to their high frequency of occurrence, persistence and possible adverse effects to exposed organisms. Concerning chiral micropollutants in the environment, enantiomers are frequently ignored and enantiomeric composition often neglected. However, enantioselective toxicity is well recognized, highlighting the need to include enantioselectivity in environmental risk assessment. Additionally, the information about enantiomeric fraction (EF is crucial since it gives insights about: (i environmental fate (i.e., occurrence, distribution, removal processes and (biodegradation; (ii illicit discharges; (iii consumption pattern (e.g., illicit drugs, pharmaceuticals used as recreational drugs, illicit use of pesticides; and (iv enantioselective toxicological effects. Thus, the purpose of this paper is to provide a comprehensive review about the enantioselective occurrence of chiral bioactive compounds in aquatic environmental matrices. These include pharmaceuticals, illicit drugs, pesticides, polychlorinated biphenyls (PCBs and polycyclic musks (PCMs. Most frequently analytical methods used for separation of enantiomers were liquid chromatography and gas chromatography methodologies using both indirect (enantiomerically pure derivatizing reagents and direct methods (chiral stationary phases. The occurrence of these chiral micropollutants in the environment is reviewed and future challenges are outlined.

  4. Laboratory diagnosis of persistent human chlamydial infection

    Directory of Open Access Journals (Sweden)

    Mirja ePuolakkainen

    2013-12-01

    Full Text Available Diagnostic assays for persistent chlamydial infection are much needed to conduct high-quality, large-scale studies investigating the persistent state in vivo, its disease associations and the response to therapy. Yet in most studies the distinction between acute and persistent infection is based on the interpretation of the data obtained by the assays developed to diagnose acute infections or on complex assays available for research only and/or difficult to establish for clinical use. Novel biomarkers for detection of persistent chlamydial infection are urgently needed. Chlamydial whole genome proteome arrays are now available and they can identify chlamydial antigens that are differentially expressed between acute infection and persistent infection. Utilizing these data will lead to the development of novel diagnostic assays. Carefully selected specimens from well-studied patient populations are clearly needed in the process of translating the proteomic data into assays useful for clinical practice. Before such antigens are identified and validated assays become available, we face a challenge of deciding whether the persistent infection truly induced appearance of the proposed marker or do we just base our diagnosis of persistent infection on the presence of the suggested markers. Consequently, we must bear this in mind when interpreting the available data.

  5. Persistent insomnia is associated with mortality risk.

    Science.gov (United States)

    Parthasarathy, Sairam; Vasquez, Monica M; Halonen, Marilyn; Bootzin, Richard; Quan, Stuart F; Martinez, Fernando D; Guerra, Stefano

    2015-03-01

    Insomnia has been associated with mortality risk, but whether this association is different in subjects with persistent vs intermittent insomnia is unclear. Additionally, the role of systemic inflammation in such an association is unknown. We used data from a community-based cohort to determine whether persistent or intermittent insomnia, defined based on persistence of symptoms over a 6-year period, was associated with death during the following 20 years of follow-up. We also determined whether changes in serum C-reactive protein (CRP) levels measured over 2 decades between study initiation and insomnia determination were different for the persistent, intermittent, and never insomnia groups. The results were adjusted for confounders such as age, sex, body mass index, smoking, physical activity, alcohol, and sedatives. Of the 1409 adult participants, 249 (18%) had intermittent and 128 (9%) had persistent insomnia. During a 20-year follow-up period, 318 participants died (118 due to cardiopulmonary disease). In adjusted Cox proportional-hazards models, participants with persistent insomnia (adjusted hazards ratio [HR] 1.58; 95% confidence interval [CI], 1.02-2.45) but not intermittent insomnia (HR 1.22; 95% CI, 0.86-1.74) were more likely to die than participants without insomnia. Serum CRP levels were higher and increased at a steeper rate in subjects with persistent insomnia as compared with intermittent (P = .04) or never (P = .004) insomnia. Although CRP levels were themselves associated with increased mortality (adjusted HR 1.36; 95% CI, 1.01-1.82; P = .04), adjustment for CRP levels did not notably change the association between persistent insomnia and mortality. In a population-based cohort, persistent, and not intermittent, insomnia was associated with increased risk for all-cause and cardiopulmonary mortality and was associated with a steeper increase in inflammation. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Twitter web-service for soft agent reporting in persistent surveillance systems

    Science.gov (United States)

    Rababaah, Haroun; Shirkhodaie, Amir

    2010-04-01

    Persistent surveillance is an intricate process requiring monitoring, gathering, processing, tracking, and characterization of many spatiotemporal events occurring concurrently. Data associated with events can be readily attained by networking of hard (physical) sensors. Sensors may have homogeneous or heterogeneous (hybrid) sensing modalities with different communication bandwidth requirements. Complimentary to hard sensors are human observers or "soft sensors" that can report occurrences of evolving events via different communication devices (e.g., texting, cell phones, emails, instant messaging, etc.) to the command control center. However, networking of human observers in ad-hoc way is rather a difficult task. In this paper, we present a Twitter web-service for soft agent reporting in persistent surveillance systems (called Web-STARS). The objective of this web-service is to aggregate multi-source human observations in hybrid sensor networks rapidly. With availability of Twitter social network, such a human networking concept can not only be realized for large scale persistent surveillance systems (PSS), but also, it can be employed with proper interfaces to expedite rapid events reporting by human observers. The proposed technique is particularly suitable for large-scale persistent surveillance systems with distributed soft and hard sensor networks. The efficiency and effectiveness of the proposed technique is measured experimentally by conducting several simulated persistent surveillance scenarios. It is demonstrated that by fusion of information from hard and soft agents improves understanding of common operating picture and enhances situational awareness.

  7. Idaho National Laboratory Quarterly Occurrence Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Lisbeth Ann [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-11-01

    This report is published quarterly by the Idaho National Laboratory (INL) Quality and Performance Management Organization. The Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS), as prescribed in DOE Order 232.2, “Occurrence Reporting and Processing of Operations Information,” requires a quarterly analysis of events, both reportable and not reportable, for the previous 12 months. This report is the analysis of 85 reportable events (18 from the 4th Qtr FY-15 and 67 from the prior three reporting quarters), as well as 25 other issue reports (including events found to be not reportable and Significant Category A and B conditions) identified at INL during the past 12 months (8 from this quarter and 17 from the prior three quarters).

  8. Familial occurrence of cerebral gigantism, Sotos' syndrome.

    Science.gov (United States)

    Hansen, F J; Friis, B

    1976-05-01

    Since the original description of cerebral gigantism, about 85 cases have been reported. Four papers comment on familial occurrence but never in parents and their children. This paper describes the syndrome in a mother and her child, which, together with facts pointing towards prenatal etiology, such as excessive birthweight, striking mutual resemblance and abnormal dermatoglyphics, points to a genetic defect. Previous endocrine studies are enlarged by the findings of normal serum somatomedin and serum prolactin.

  9. Occurrence of antimicrobial resistance among bacterial pathogens

    OpenAIRE

    Hendriksen, Rene S.; Mevius, Dik J.; Schroeter, Andreas; Teale, Christopher; Jouy, Eric; Butaye, Patrick; Franco, Alessia; Utinane, Andra; Amado, Alice; Moreno, Miguel; Greko, Christina; Stärk, Katharina D.C.; Berghold, Christian; Myllyniemi, Anna-Liisa; Hoszowski, Andrzej

    2008-01-01

    Background: The project "Antibiotic resistance in bacteria of animal origin – II" (ARBAO-II) was funded by the European Union (FAIR5-QLK2-2002-01146) for the period 2003–05. The aim of this project was to establish a program for the continuous monitoring of antimicrobial susceptibility of pathogenic and indicator bacteria from food animals using validated and harmonised methodologies. In this report the first data on the occurrence of antimicrobial resistance among bacteria cau...

  10. Near-total pancreatectomy for persistent hyperinsulinemic ...

    African Journals Online (AJOL)

    of persistent hypoglycemia in infancy with consequences ... (PHHI) is the most common cause of recurrent and per- sistent hypoglycemia in infancy and childhood. Causes .... a high rate of pancreatic surgery in the neonatal-onset group.

  11. The persistent stereotype: children's images of scientists

    Science.gov (United States)

    Emens McAdam, Janice

    1990-03-01

    Through their reading children learn to regard scientists as eccentrics. It is shown that this stereotype has persisted for over thirty years and affects many adult attitudes. Some methods of breaking the author-reader cycle are suggested.

  12. Active Longitude and Solar Flare Occurrences

    Science.gov (United States)

    Gyenge, N.; Ludmány, A.; Baranyi, T.

    2016-02-01

    The aim of the present work is to specify the spatio-temporal characteristics of flare activity observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Geostationary Operational Environmental Satellite (GOES) in connection with the behavior of the longitudinal domain of enhanced sunspot activity known as active longitude (AL). By using our method developed for this purpose, we identified the AL in every Carrington Rotation provided by the Debrecen Photoheliographic Data. The spatial probability of flare occurrence has been estimated depending on the longitudinal distance from AL in the northern and southern hemispheres separately. We have found that more than 60% of the RHESSI and GOES flares is located within +/- 36^\\circ from the AL. Hence, the most flare-productive active regions tend to be located in or close to the active longitudinal belt. This observed feature may allow for the prediction of the geo-effective position of the domain of enhanced flaring probability. Furthermore, we studied the temporal properties of flare occurrence near the AL and several significant fluctuations were found. More precisely, the results of the method are the following fluctuations: 0.8, 1.3, and 1.8 years. These temporal and spatial properties of the solar flare occurrence within the active longitudinal belts could provide us with an enhanced solar flare forecasting opportunity.

  13. Persisting nutritional neuropathy amongst former war prisoners.

    OpenAIRE

    Gill, G V; Bell, D R

    1982-01-01

    Of 898 former Far East prisoners of war, assessed between 1968 and 1981, 49 (5.5%) had evidence of persisting symptomatic neurological disease dating back to their periods of malnutrition in captivity. The commonest syndromes were peripheral neuropathy (often of "burning foot" type), optic atrophy, and sensori-neural deafness. Though nutritional neuropathies disappeared soon after release in most ex-Far East prisoners of war, in some they have persisted up to 36 years since exposure to the nu...

  14. Long - Memory Persistence in African Stock Markets

    Directory of Open Access Journals (Sweden)

    Emmanuel Numapau Gyamfi

    2016-05-01

    Full Text Available Emerging stock markets are said to become efficient with time. This study seeks to investigate this assertion by analyzing long - memory persistence in 8 African stock markets covering the period from 28 August 2000 to 28 August 2015. The Hurst exponent is used as our efficiency measure which is evaluated by the Detrended Fluctuation Analysis (DFA. Our findings show strong evidence of long - memory persistence in the markets studied therefore violating the weak - form Efficient Market Hypothesis (EMH.

  15. Persistent Mullerian Duct Syndrome with Transverse Testicular ...

    African Journals Online (AJOL)

    Eastham JA, McEvoy K, Sullivan R, Chandrasoma P. A case of simultaneous bilateral nonseminomatous testicular tumors in persistent müllerian duct syndrome. J Urol 1992;148:407-8. 8. Shinmura Y, Yokoi T, Tsutsui Y. A case of clear cell adenocarcinoma of the müllerian duct in persistent müllerian duct syndrome: The first ...

  16. Hyperthyroidism as a cause of persistent vomiting.

    Science.gov (United States)

    Hoogendoorn, E H; Cools, B M

    2004-09-01

    A 32-year-old woman presented with persistent vomiting, epigastric pain and weight loss. A sinus tachycardia was the clue to the diagnosis of hyperthyroidism due to Graves' disease. On treatment with propylthiouracil and a beta-blocking agent, her symptoms resolved within one day, even though her free thyroxine level was still high. Hyperthyroidism is an uncommon, but previously reported cause of persistent vomiting.

  17. Hyperthyroidism as a cause of persistent vomiting.

    OpenAIRE

    Hoogendoorn, E.H.; Cools, B.M.

    2004-01-01

    A 32-year-old woman presented with persistent vomiting, epigastric pain and weight loss. A sinus tachycardia was the clue to the diagnosis of hyperthyroidism due to Graves' disease. On treatment with propylthiouracil and a beta-blocking agent, her symptoms resolved within one day, even though her free thyroxine level was still high. Hyperthyroidism is an uncommon, but previously reported cause of persistent vomiting.

  18. "It's overwhelming... everything seems to be too much:" A theory of crisis for individuals with severe persistent mental illness.

    Science.gov (United States)

    Ball, Jeffrey S; Links, Paul S; Strike, Carol; Boydell, Katherine M

    2005-01-01

    Crisis in individuals with severe persistent mental illness (SPMI) is a poorly understood phenomenon for which traditional crisis models do not apply. In this study we explored the crisis experience using in-depth interviews conducted with individuals with severe persistent mental illness from two community support programs. A grounded theory of the crisis experience was developed and the results illustrate that underlying vulnerability sets the stage for crisis occurrence which involves feeling overwhelmed and lacking control and manifests as agitation/anger/aggression, being low, feeling anxious, or euphoria. Immediate responses to crises involve getting help or managing alone and numerous factors contribute to crisis resolution and prevention.

  19. Herbicide Persistence in Seawater Simulation Experiments.

    Directory of Open Access Journals (Sweden)

    Philip Mercurio

    Full Text Available Herbicides are detected year-round in marine waters, including those of the World Heritage listed Great Barrier Reef (GBR. The few previous studies that have investigated herbicide persistence in seawater generally reported half-lives in the order of months, and several studies were too short to detect significant degradation. Here we investigated the persistence of eight herbicides commonly detected in the GBR or its catchments in standard OECD simulation flask experiments, but with the aim to mimic natural conditions similar to those found on the GBR (i.e., relatively low herbicide concentrations, typical temperatures, light and microbial communities. Very little degradation was recorded over the standard 60 d period (Experiment 1 so a second experiment was extended to 365 d. Half-lives of PSII herbicides ametryn, atrazine, diuron, hexazinone and tebuthiuron were consistently greater than a year, indicating high persistence. The detection of atrazine and diuron metabolites and longer persistence in mercuric chloride-treated seawater confirmed that biodegradation contributed to the breakdown of herbicides. The shortest half-life recorded was 88 d for growth-regulating herbicide 2,4-D at 31°C in the dark, while the fatty acid-inhibitor metolachlor exhibited a minimum half-life of 281 d. The presence of moderate light and elevated temperatures affected the persistence of most of the herbicides; however, the scale and direction of the differences were not predictable and were likely due to changes in microbial community composition. The persistence estimates here represent some of the first appropriate data for application in risk assessments for herbicide exposure in tropical marine systems. The long persistence of herbicides identified in the present study helps explain detection of herbicides in nearshore waters of the GBR year round. Little degradation of these herbicides would be expected during the wet season with runoff and associated

  20. Herbicide Persistence in Seawater Simulation Experiments

    Science.gov (United States)

    Mercurio, Philip; Mueller, Jochen F.; Eaglesham, Geoff; Flores, Florita; Negri, Andrew P.

    2015-01-01

    Herbicides are detected year-round in marine waters, including those of the World Heritage listed Great Barrier Reef (GBR). The few previous studies that have investigated herbicide persistence in seawater generally reported half-lives in the order of months, and several studies were too short to detect significant degradation. Here we investigated the persistence of eight herbicides commonly detected in the GBR or its catchments in standard OECD simulation flask experiments, but with the aim to mimic natural conditions similar to those found on the GBR (i.e., relatively low herbicide concentrations, typical temperatures, light and microbial communities). Very little degradation was recorded over the standard 60 d period (Experiment 1) so a second experiment was extended to 365 d. Half-lives of PSII herbicides ametryn, atrazine, diuron, hexazinone and tebuthiuron were consistently greater than a year, indicating high persistence. The detection of atrazine and diuron metabolites and longer persistence in mercuric chloride-treated seawater confirmed that biodegradation contributed to the breakdown of herbicides. The shortest half-life recorded was 88 d for growth-regulating herbicide 2,4-D at 31°C in the dark, while the fatty acid-inhibitor metolachlor exhibited a minimum half-life of 281 d. The presence of moderate light and elevated temperatures affected the persistence of most of the herbicides; however, the scale and direction of the differences were not predictable and were likely due to changes in microbial community composition. The persistence estimates here represent some of the first appropriate data for application in risk assessments for herbicide exposure in tropical marine systems. The long persistence of herbicides identified in the present study helps explain detection of herbicides in nearshore waters of the GBR year round. Little degradation of these herbicides would be expected during the wet season with runoff and associated flood plumes

  1. Persistence of Bacteroides ovatus under simulated sunlight irradiation

    KAUST Repository

    Dong, Shengkun

    2014-07-04

    Background: Bacteroides ovatus, a member of the genus Bacteroides, is considered for use in molecular-based methods as a general fecal indicator. However, knowledge on its fate and persistence after a fecal contamination event remains limited. In this study, the persistence of B. ovatus was evaluated under simulated sunlight exposure and in conditions similar to freshwater and seawater. By combining propidium monoazide (PMA) treatment and quantitative polymerase chain reaction (qPCR) detection, the decay rates of B. ovatus were determined in the presence and absence of exogenous photosensitizers and in salinity up to 39.5 parts per thousand at 27°C. Results: UVB was found to be important for B. ovatus decay, averaging a 4 log10 of decay over 6 h of exposure without the presence of extracellular photosensitizers. The addition of NaNO2, an exogenous sensitizer producing hydroxyl radicals, did not significantly change the decay rate of B. ovatus in both low and high salinity water, while the exogenous sensitizer algae organic matter (AOM) slowed down the decay of B. ovatus in low salinity water. At seawater salinity, the decay rate of B. ovatus was slower than that in low salinity water, except when both NaNO2 and AOM were present. Conclusion: The results of laboratory experiments suggest that if B. ovatus is released into either freshwater or seawater environment in the evening, 50% of it may be intact by the next morning; if it is released at noon, only 50% may be intact after a mere 5 min of full spectrum irradiation on a clear day. This study provides a mechanistic understanding to some of the important environmental relevant factors that influenced the inactivation kinetics of B. ovatus in the presence of sunlight irradiation, and would facilitate the use of B. ovatus to indicate the occurrence of fecal contamination.

  2. Polyfluoroalkyl compounds in the aquatic environment: a review of their occurrence and fate.

    Science.gov (United States)

    Ahrens, Lutz

    2011-01-01

    The occurrence and fate of polyfluoroalkyl compounds (PFCs) in the aquatic environment has been recognized as one of the emerging issues in environmental chemistry. PFCs comprise a diverse group of chemicals that are widely used as processing additives during fluoropolymer production and as surfactants in consumer applications for over 50 years. PFCs are known to be persistent, bioaccumulative and have possible adverse effects on humans and wildlife. As a result, perfluorooctane sulfonate (PFOS) has been added to the persistent organic pollutants (POPs) list of the Stockholm Convention in May 2009. However, their homologues, neutral precursor compounds and new PFCs classes continue to be produced. In general, several PFCs from different classes have been detected ubiquitously in the aqueous environment while the concentrations usually range between pg and ng per litre for individual compounds. Sources of PFCs into the aqueous environment are both point sources (e.g., wastewater treatment plant effluents) and nonpoint sources (e.g., surface runoff). The detected congener composition in environmental samples depends on their physicochemical characteristics and may provide information to their sources and transport pathways. However, the dominant transport pathways of individual PFCs to remote regions have not been conclusively characterised to date. The objective of this article is to give an overview on existing knowledge of the occurrence, fate and processes of PFCs in the aquatic environment. Finally, this article identifies knowledge gaps, presents conclusions and recommendations for future work.

  3. The Occurrence of Erionite at Yucca Mountain

    International Nuclear Information System (INIS)

    NA

    2004-01-01

    The naturally-occurring zeolite mineral erionite has a fibrous morphology and is a known human carcinogen (inhalation hazard). Erionite has been found typically in very small quantities and restricted occurrences in the course of mineralogic characterization of Yucca Mountain as a host for a high-level nuclear waste repository. The first identification of erionite was made in 1984 on the basis of morphology and chemical composition and later confirmed by X-ray diffraction analysis. It was found in the lower vitrophyre (Tptpv3) of the Topopah Spring Tuff in a borehole sidewall sample. Most erionite occurrences identified at Yucca Mountain are in the Topopah Spring Tuff, within an irregular zone of transition between the lower boundary of devitrified tuff and underlying glassy tuff. This zone is fractured and contains intermingled devitrified and vitric tuff. In 1997, a second host of erionite mineralization was identified in the Exploratory Studies Facility within and adjacent to a high-angle fracture/breccia zone transgressing the boundary between the lowermost devitrified tuff (Tpcplnc) and underlying moderately welded vitric tuff (Tpcpv2) of the Tiva Canyon Tuff. The devitrified-vitric transition zones where erionite is found tend to have complex secondary-mineral assemblages, some of very localized occurrence. Secondary minerals in addition to erionite may include smectite, heulandite-clinoptilolite, chabazite, opal-A, opal-CT, cristobalite, quartz, kenyaite, and moganite. Incipient devitrification within the Topopah Spring Tuff transition zone includes patches that are highly enriched in potassium feldspar relative to the precursor volcanic glass. Geochemical conditions during glass alteration may have led to local evolution of potassium-rich fluids. Thermodynamic modeling of zeolite stability shows that erionite and chabazite stability fields occur only at aqueous K concentrations much higher than in present Yucca Mountain waters. The association of erionite

  4. Uranium - the element: its occurrence and uses

    International Nuclear Information System (INIS)

    Awan, I. Z.

    2015-01-01

    Uranium metal and its compounds have been of great interest to physicists and chemists due to its use for both civil and military applications, e.g. production of electricity, use in the medical field and for making nuclear weapons. This review paper describes the occurrence, chemistry and metallurgy of the element 'uranium', its conversion to stable compounds such as yellow cake, uranium tetrafluoride and uranium hexafluoride and the enrichment technologies and uses for both civil and military purposes. The paper is meant for ready reference for students and teachers in connection with the recent spate of interest shown in nuclear power generation in Pakistan and abroad. (author)

  5. Exudate gums: occurrence, production, and applications.

    Science.gov (United States)

    Verbeken, D; Dierckx, S; Dewettinck, K

    2003-11-01

    This paper presents a review of the industrially most relevant exudate gums: gum arabic, gum karya, and gum tragacanth. Exudate gums are obtained as the natural exudates of different tree species and exhibit unique properties in a wide variety of applications. This review covers the chemical structure, occurrence and production of the different gums. It also deals with the size and relative importance of the various players on the world market. Furthermore, it gives an overview of the main application fields of the different gums, both food and non-food.

  6. Malaria and pneumonia occurrence in Lagos, Nigeria: Role of ...

    African Journals Online (AJOL)

    EJIRO

    profound influence on both malaria and pneumonia occurrence and are responsible directly for ... Key words: Malaria occurrence, change points, climate- disease, pneumonia. ..... formation of tall clouds and onset of rainy season, we observe ...

  7. Epithermal gold occurrences in the lakes district of the Main ...

    African Journals Online (AJOL)

    MER). Epithermal gold occurrences related to Quaternary volcanics are at present being closely studied for their precious metal potential. Low sulphidation (Adularia-sericite-type) occurrences have been found. Analyses of 579 core and cutting ...

  8. Generating Dynamic Persistence in the Time Domain

    Science.gov (United States)

    Guerrero, A.; Smith, L. A.; Smith, L. A.; Kaplan, D. T.

    2001-12-01

    Many dynamical systems present long-range correlations. Physically, these systems vary from biological to economical, including geological or urban systems. Important geophysical candidates for this type of behaviour include weather (or climate) and earthquake sequences. Persistence is characterised by slowly decaying correlation function; that, in theory, never dies out. The Persistence exponent reflects the degree of memory in the system and much effort has been expended creating and analysing methods that successfully estimate this parameter and model data that exhibits persistence. The most widely used methods for generating long correlated time series are not dynamical systems in the time domain, but instead are derived from a given spectral density. Little attention has been drawn to modelling persistence in the time domain. The time domain approach has the advantage that an observation at certain time can be calculated using previous observations which is particularly suitable when investigating the predictability of a long memory process. We will describe two of these methods in the time domain. One is a traditional approach using fractional ARIMA (autoregressive and moving average) models; the second uses a novel approach to extending a given series using random Fourier basis functions. The statistical quality of the two methods is compared, and they are contrasted with weather data which shows, reportedly, persistence. The suitability of this approach both for estimating predictability and for making predictions is discussed.

  9. Persistent agents in Axelrod's social dynamics model

    Science.gov (United States)

    Reia, Sandro M.; Neves, Ubiraci P. C.

    2016-01-01

    Axelrod's model of social dynamics has been studied under the effect of external media. Here we study the formation of cultural domains in the model by introducing persistent agents. These are agents whose cultural traits are not allowed to change but may be spread through local neighborhood. In the absence of persistent agents, the system is known to present a transition from a monocultural to a multicultural regime at some critical Q (number of traits). Our results reveal a dependence of critical Q on the occupation probability p of persistent agents and we obtain the phase diagram of the model in the (p,Q) -plane. The critical locus is explained by the competition of two opposite forces named here barrier and bonding effects. Such forces are verified to be caused by non-persistent agents which adhere (adherent agents) to the set of traits of persistent ones. The adherence (concentration of adherent agents) as a function of p is found to decay for constant Q. Furthermore, adherence as a function of Q is found to decay as a power law with constant p.

  10. Terbuthylazine and desethylterbuthylazine: Recent occurrence, mobility and removal techniques.

    Science.gov (United States)

    Tasca, Andrea Luca; Puccini, Monica; Fletcher, Ashleigh

    2018-07-01

    The herbicide terbuthylazine (TBA) has displaced atrazine in most of EU countries, becoming one of the most regularly used pesticides and, therefore, frequently detected in natural waters. The affinity of TBA for soil organic matter suggests prolonged contamination; degradation leads to the release of the metabolite desethylterbuthylazine (DET), which has higher water solubility and binds more weakly to organic matter compared to the parent compound, resulting in higher associated risk for contamination of groundwater resources. Additionally, TBA and DET are chemicals of emerging concern because of their persistence and toxicity towards aquatic organisms; moreover, they are known to have significant endocrine disruption capacity to wildlife and humans. Conventional treatments applied during drinking water production do not lead to the complete removal of these chemicals; activated carbon provides the greatest efficiency, whereas ozonation can generate by-products with comparable oestrogenic activity to atrazine. Hydrogen peroxide alone is ineffective to degrade TBA, while UV/H 2 O 2 advanced oxidation and photocatalysis are the most effective processes for oxidation of TBA. It has been determined that direct photolysis gives the highest degradation efficiency of all UV/H 2 O 2 treatments, while most of the photocatalytic degradation is attributed to OH radicals, and TiO 2 solar-photocatalytic ozonation can lead to almost complete TBA removal in ∼30 min. Constructed wetlands provide a valuable buffer capacity, protecting downstream surface waters from contaminated runoff. TBA and DET occurrence are summarized and removal techniques are critically evaluated and compared, to provide the reader with a comprehensive guide to state-of-the-art TBA removal and potential future treatments. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. 46 CFR 326.4 - Reports of accidents and occurrences.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Reports of accidents and occurrences. 326.4 Section 326... MARINE PROTECTION AND INDEMNITY INSURANCE UNDER AGREEMENTS WITH AGENTS § 326.4 Reports of accidents and occurrences. The Agent shall report every accident or occurrence of a P&I nature promptly to both the Director...

  12. Formulating accident occurrence as a survival process.

    Science.gov (United States)

    Chang, H L; Jovanis, P P

    1990-10-01

    A conceptual framework for accident occurrence is developed based on the principle of the driver as an information processor. The framework underlies the development of a modeling approach that is consistent with the definition of exposure to risk as a repeated trial. Survival theory is proposed as a statistical technique that is consistent with the conceptual structure and allows the exploration of a wide range of factors that contribute to highway operating risk. This survival model of accident occurrence is developed at a disaggregate level, allowing safety researchers to broaden the scope of studies which may be limited by the use of traditional aggregate approaches. An application of the approach to motor carrier safety is discussed as are potential applications to a variety of transportation industries. Lastly, a typology of highway safety research methodologies is developed to compare the properties of four safety methodologies: laboratory experiments, on-the-road studies, multidisciplinary accident investigations, and correlational studies. The survival theory formulation has a mathematical structure that is compatible with each safety methodology, so it may facilitate the integration of findings across methodologies.

  13. [Congenital talipes equinovarus--family occurrence].

    Science.gov (United States)

    Kołecka, Ewa; Niedzielski, Kryspin Ryszard; Cukras, Zbigniew; Piotrowicz, Małgorzata

    2011-01-01

    Although congenital talipes equinovarus (CTEV) is one of the most frequently occurring congenital defects of locomotor organs, its ethiopathogenesis is still not fully known. Amongst the others, the inheritance patterns of that defect are not fully known, and that restricts genetic therapeutics and development of new treatment technologies. The aim of this study was analysis of family lineages of 205 children with CTEV (298 feet) treated at our centre in the years 1998-2008. The family occurrence of CTEV was found in 16 cases (8% of analysed group). 6 lineages, in which CTEV occurred in successive generations, were analysed in detail. Particularly interesting is the lineage of the family 1, in which the defect occurred in three successive generations. In case of that family, an autosomal dominant inheritance pattern is possible. Previously that pattern of CTEV inheritance was described only for isolated populations of Polynesians. In own material the family occurrence of CTEV was found to be less frequent than in bibliographic references. The defect occurred twice as often in boys, while the severe form was more frequently observed in girls, and that is consisted with data in the available bibliography. The analysis of presented lineages of families with CTEV did not allow unambiguous defining of the inheritance pattern for that defect. To confirm the autosomal dominant pattern of CTEV inheritance in the family in which the defect occurred in three successive generations, genetic tests would be necessary.

  14. The Economy of Persistence: Mario the Tailor

    Directory of Open Access Journals (Sweden)

    Prudence Black

    2016-03-01

    Full Text Available Mario Conte has had a tailor shop in King Street, Newtown since the mid 1960s. Taking an interview with Mario as its point of departure, this article describes the persistence of a skilled worker whose practices and techniques remain the same in a world that has long changed. While inattentive to what rules might be used to decorate a shop window, Mario continues to make and sew in the way that he learnt in post-war Italy. Mario’s persistence could be described as all the skills and other elements that need to be in place to keep him working, in particular the tradition of tailoring techniques he has remained true to over the last fifty years. The hand stitching of his tailoring is like a metronome of that persistence.

  15. Understanding mild persistent asthma in children

    DEFF Research Database (Denmark)

    Bisgaard, Hans; Szefler, Stanley J

    2005-01-01

    Limitations in asthma prevalence studies and difficulties in diagnosing pediatric asthma lead to uncertainty over the full extent of mild persistent asthma in children and adolescents. Although recent surveys have reported that the majority of pediatric patients with asthma in the United States...... and Europe have symptoms consistent with mild disease, these surveys have limitations in design. Thus, the true prevalence of mild asthma remains unknown. It is unclear whether children with mild persistent asthma progress to more severe asthma, but the risk of severe asthma exacerbations seems...... to be unrelated to the symptom severity. Clinical studies restricted to pediatric patients with mild asthma are limited, but available data do suggest substantial morbidity of mild persistent asthma in this population and support inhaled corticosteroid intervention. There is a need for further investigation...

  16. International perspectives on retention and persistence

    Directory of Open Access Journals (Sweden)

    Gary Burkholder

    2014-06-01

    Full Text Available Access to higher education globally is increasing dramatically; attainment of tertiary degrees is a high priority, as educational attainment is associated with increased personal incomes as well as growth of the middle class in developing countries. The purpose of this essay is to briefly examine retention and persistence issues from a global perspective, review some retention strategies that have been employed at schools outside the United States, and to identify several key factors that related to retention and persistence globally, including access, infrastructure, financial consideration, and readiness for tertiary education.  There exists an opportunity to utilize knowledge gained in the evolution of the higher education system in the United States to help address the problems associated with retention and persistence.   DOI: 10.18870/hlrc.v4i2.208

  17. Persistent toxic substances: sources, fates and effects.

    Science.gov (United States)

    Wong, Ming H; Armour, Margaret-Ann; Naidu, Ravi; Man, Ming

    2012-01-01

    Persistent toxic substances (PTS) include the Stockholm persistent organic pollutants, like dichlorodiphenyltrichloroethane, polychlorinated biphenyls, dioxin/furan, etc., and organometallic compounds, like organomercury, organotin, and organolead, which all share the same characteristics of being persistent, toxic, bioaccumulative, and able to travel long distances through different media. The adverse health effects of some of the emerging chemicals like pentabromodiphenyl ether, bisphenol A, and di(2-ethylhexyl)phthalate, which are widely used in daily appliances (e.g., TVs, computers, mobile phones, plastic baby bottles), have become a public health concern due to more evidence now available showing their adverse effects like disturbance of the endocrine system and cancer. This article is an attempt to review the current status of PTS in our environment, citing case studies in China and North America, and whether our existing drinking water treatment and wastewater treatment processes are adequate in removing them from water. Some management issues of these emerging chemicals of concern are also discussed.

  18. Modeling Real Exchange Rate Persistence in Chile

    Directory of Open Access Journals (Sweden)

    Leonardo Salazar

    2017-07-01

    Full Text Available The long and persistent swings in the real exchange rate have for a long time puzzled economists. Recent models built on imperfect knowledge economics seem to provide a theoretical explanation for this persistence. Empirical results, based on a cointegrated vector autoregressive (CVAR model, provide evidence of error-increasing behavior in prices and interest rates, which is consistent with the persistence observed in the data. The movements in the real exchange rate are compensated by movements in the interest rate spread, which restores the equilibrium in the product market when the real exchange rate moves away from its long-run benchmark value. Fluctuations in the copper price also explain the deviations of the real exchange rate from its long-run equilibrium value.

  19. Review on the occurrence and profiles of polybrominated diphenyl ethers in the Philippines.

    Science.gov (United States)

    Mackintosh, Susan A; Wallace, Joshua S; Gross, Michael S; Navarro, Denise D; Pérez-Fuentetaja, Alicia; Alaee, Mehran; Montecastro, Doris; Aga, Diana S

    2015-12-01

    The environmental occurrence of polybrominated diphenyl ethers (PBDEs) has been a subject of concern for the past decade because they are persistent, bioaccumulative, and toxic. These compounds have been listed as persistent organic pollutants (POPs) by the Stockholm Convention and are expected to disperse in the global environment even after their use and production. While the occurrence of PBDEs has been well characterized in environmental and biological samples from North America, Europe, and some Asian countries (i.e. China, Japan, and Korea), there is a scarcity of available data in developing Asian countries, such as the Philippines. Examination of PBDE contamination in the Philippine environment is particularly important because regulations have only recently been implemented on the production and use of PBDEs in this country. Additionally, the Philippines receives e-waste from Western countries, which is becoming a major source of organic contaminants in the tropical Asian regions. Ultimately, the Philippines may be a hot spot for contributing to on-going global PBDE pollution due to long-range atmospheric transport. This paper presents a review of the available literature on PBDEs in both environmental and biological samples collected from the Philippines. It is also intended to provide an overview on the levels and congener profiles of PBDEs in samples from the Philippines and to compare these data with other Asian countries. New data are presented on PBDE occurrence and congener profiles in fish commonly consumed by Filipinos and in particulate matter samples collected in Metro Manila, the capital of the Philippines. Both studies contribute to the available knowledge of PBDEs in the Philippines. We aim to stress the importance of future studies in countries receiving e-wastes, such as the Philippines, and suggest what future directions might be taken to enhance the available data on the presence of PBDEs in the Philippine environment. Copyright © 2015

  20. Stochastic persistence and stationary distribution in an SIS epidemic model with media coverage

    Science.gov (United States)

    Guo, Wenjuan; Cai, Yongli; Zhang, Qimin; Wang, Weiming

    2018-02-01

    This paper aims to study an SIS epidemic model with media coverage from a general deterministic model to a stochastic differential equation with environment fluctuation. Mathematically, we use the Markov semigroup theory to prove that the basic reproduction number R0s can be used to control the dynamics of stochastic system. Epidemiologically, we show that environment fluctuation can inhibit the occurrence of the disease, namely, in the case of disease persistence for the deterministic model, the disease still dies out with probability one for the stochastic model. So to a great extent the stochastic perturbation under media coverage affects the outbreak of the disease.

  1. The origins of lactase persistence in Europe.

    Directory of Open Access Journals (Sweden)

    Yuval Itan

    2009-08-01

    Full Text Available Lactase persistence (LP is common among people of European ancestry, but with the exception of some African, Middle Eastern and southern Asian groups, is rare or absent elsewhere in the world. Lactase gene haplotype conservation around a polymorphism strongly associated with LP in Europeans (-13,910 C/T indicates that the derived allele is recent in origin and has been subject to strong positive selection. Furthermore, ancient DNA work has shown that the--13,910*T (derived allele was very rare or absent in early Neolithic central Europeans. It is unlikely that LP would provide a selective advantage without a supply of fresh milk, and this has lead to a gene-culture coevolutionary model where lactase persistence is only favoured in cultures practicing dairying, and dairying is more favoured in lactase persistent populations. We have developed a flexible demic computer simulation model to explore the spread of lactase persistence, dairying, other subsistence practices and unlinked genetic markers in Europe and western Asia's geographic space. Using data on--13,910*T allele frequency and farming arrival dates across Europe, and approximate Bayesian computation to estimate parameters of interest, we infer that the--13,910*T allele first underwent selection among dairying farmers around 7,500 years ago in a region between the central Balkans and central Europe, possibly in association with the dissemination of the Neolithic Linearbandkeramik culture over Central Europe. Furthermore, our results suggest that natural selection favouring a lactase persistence allele was not higher in northern latitudes through an increased requirement for dietary vitamin D. Our results provide a coherent and spatially explicit picture of the coevolution of lactase persistence and dairying in Europe.

  2. The origins of lactase persistence in Europe.

    Science.gov (United States)

    Itan, Yuval; Powell, Adam; Beaumont, Mark A; Burger, Joachim; Thomas, Mark G

    2009-08-01

    Lactase persistence (LP) is common among people of European ancestry, but with the exception of some African, Middle Eastern and southern Asian groups, is rare or absent elsewhere in the world. Lactase gene haplotype conservation around a polymorphism strongly associated with LP in Europeans (-13,910 C/T) indicates that the derived allele is recent in origin and has been subject to strong positive selection. Furthermore, ancient DNA work has shown that the--13,910*T (derived) allele was very rare or absent in early Neolithic central Europeans. It is unlikely that LP would provide a selective advantage without a supply of fresh milk, and this has lead to a gene-culture coevolutionary model where lactase persistence is only favoured in cultures practicing dairying, and dairying is more favoured in lactase persistent populations. We have developed a flexible demic computer simulation model to explore the spread of lactase persistence, dairying, other subsistence practices and unlinked genetic markers in Europe and western Asia's geographic space. Using data on--13,910*T allele frequency and farming arrival dates across Europe, and approximate Bayesian computation to estimate parameters of interest, we infer that the--13,910*T allele first underwent selection among dairying farmers around 7,500 years ago in a region between the central Balkans and central Europe, possibly in association with the dissemination of the Neolithic Linearbandkeramik culture over Central Europe. Furthermore, our results suggest that natural selection favouring a lactase persistence allele was not higher in northern latitudes through an increased requirement for dietary vitamin D. Our results provide a coherent and spatially explicit picture of the coevolution of lactase persistence and dairying in Europe.

  3. Inferring differential evolutionary processes of plant persistence traits in Northern Hemisphere Mediterranean fire-prone ecosystems

    Science.gov (United States)

    Pausas, J.G.; Keeley, J.E.; Verdu, M.

    2006-01-01

    1 Resprouting capacity (R) and propagule-persistence (P) are traits that are often considered to have evolved where there are predictable crown fires. Because several indicators suggest a stronger selective pressure for such traits in California than in the Mediterranean Basin, we hypothesize that plant species should have evolved to become R+ and P+ more frequently in California than in the Mediterranean Basin. 2 To test this hypothesis we studied the phylogenetic association between R and P states in both California and the Mediterranean Basin using published molecular phylogenies. 3 The results suggest that R and P evolved differently in the two regions. The occurrence of the states differs significantly between regions for trait P, but not for trait R. The different patterns (towards R+ and P+ in California and towards R+ and P- in the Mediterranean Basin) are reflected in the higher abundance and the wider taxonomic distribution of species with both persistence traits (R+P+ species) in California. 4 The differential acquisition of fire persistence mechanisms at the propagule level (P+) supports the idea that fire selective pressures has been higher in California than in the Mediterranean Basin. 5 Our comparative phylogenetic-informed analysis contributes to an understanding of the differential role of the Quaternary climate in determining fire persistence traits in different Mediterranean-type ecosystems and, thus, to the debate on the evolutionary convergence of traits. ?? 2006 British Ecological Society.

  4. The natural course of anxiety symptoms in early adolescence: factors related to persistence.

    Science.gov (United States)

    Voltas, Núria; Hernández-Martínez, Carmen; Arija, Victoria; Canals, Josefa

    2017-11-01

    Anxiety disorders are the most common mental health problems during childhood and adolescence. This study examined the course of anxiety symptoms in early adolescents from the general population over three phases. Prospective cohort study. Two hundred and forty-two participants (mean-age of 13.52) from a baseline sample of 1514 (mean-age of 10.23) were followed up three times. Of the 1514 children, those with emotional risk and controls without risk constituted the second-phase sample (n = 562; mean-age of 11.25). The Screen for Child Anxiety Related Emotional Disorders-SCARED was administered in all three phases. Fifty-six percent and 32% of respondents showed total scores above the SCARED cutoff point at one and three years follow-up, respectively. Eight percent showed fluctuating symptoms. Fifty-five percent of respondents showed high scores for any subtype of anxiety over three years. Social phobia and generalized anxiety symptoms were the most prevalent and persistent. Participants with persistent separation anxiety showed the highest co-occurrence with symptoms of other psychopathological disorders. Participants with persistent anxiety showed lower academic performance. Being male was a protective factor against persistence. The data support anxiety maintenance during early adolescence. Early adolescence is a critical period which may involve other serious academic, social, and family problems.

  5. Persisting nutritional neuropathy amongst former war prisoners.

    Science.gov (United States)

    Gill, G V; Bell, D R

    1982-01-01

    Of 898 former Far East prisoners of war, assessed between 1968 and 1981, 49 (5.5%) had evidence of persisting symptomatic neurological disease dating back to their periods of malnutrition in captivity. The commonest syndromes were peripheral neuropathy (often of "burning foot" type), optic atrophy, and sensori-neural deafness. Though nutritional neuropathies disappeared soon after release in most ex-Far East prisoners of war, in some they have persisted up to 36 years since exposure to the nutritional insult. PMID:6292369

  6. PERSISTENCY ANALYSIS OF PARTICIPANTS OF PENSION PLANS

    OpenAIRE

    ROBERTA DE SOUZA CHUN

    2007-01-01

    O tema central deste trabalho é apresentar modelos de persistência. As probabilidades de persistência na carteira de um produto de determinada empresa de seguros e previdência serão estudadas de forma agregada, de tal forma que se torna possível a elaboração de outros estudos, como por exemplo, de análise de lucratividade, mesmo com poucos dados, o que inviabiliza a elaboração de tábuas de múltiplos decrementos. Serão avaliadas as possíveis causas de saí...

  7. Amnestically Induced Persistence in Random Walks

    Science.gov (United States)

    Cressoni, J. C.; da Silva, Marco Antonio Alves; Viswanathan, G. M.

    2007-02-01

    We study how the Hurst exponent α depends on the fraction f of the total time t remembered by non-Markovian random walkers that recall only the distant past. We find that otherwise nonpersistent random walkers switch to persistent behavior when inflicted with significant memory loss. Such memory losses induce the probability density function of the walker’s position to undergo a transition from Gaussian to non-Gaussian. We interpret these findings of persistence in terms of a breakdown of self-regulation mechanisms and discuss their possible relevance to some of the burdensome behavioral and psychological symptoms of Alzheimer’s disease and other dementias.

  8. The Persistence of Long Work Hours

    OpenAIRE

    Robert Drago; David Black; Mark Wooden

    2005-01-01

    Previous research hypothesizes that long working hours are related to consumerism, the ideal worker norm, high levels of human capital, and a high cost-of-job-loss. The authors test these hypotheses using panel data on working hours for an Australian sample of full-time employed workers. Analyses include a static cross-sectional model and a persistence model for long hours over time. The results suggest that long hours (50 or more hours in a usual week) are often persistent, and provide stron...

  9. Fusariotoxins in Avian Species: Toxicokinetics, Metabolism and Persistence in Tissues

    Directory of Open Access Journals (Sweden)

    Philippe Guerre

    2015-06-01

    Full Text Available Fusariotoxins are mycotoxins produced by different species of the genus Fusarium whose occurrence and toxicity vary considerably. Despite the fact avian species are highly exposed to fusariotoxins, the avian species are considered as resistant to their toxic effects, partly because of low absorption and rapid elimination, thereby reducing the risk of persistence of residues in tissues destined for human consumption. This review focuses on the main fusariotoxins deoxynivalenol, T-2 and HT-2 toxins, zearalenone and fumonisin B1 and B2. The key parameters used in the toxicokinetic studies are presented along with the factors responsible for their variations. Then, each toxin is analyzed separately. Results of studies conducted with radiolabelled toxins are compared with the more recent data obtained with HPLC/MS-MS detection. The metabolic pathways of deoxynivalenol, T-2 toxin, and zearalenone are described, with attention paid to the differences among the avian species. Although no metabolite of fumonisins has been reported in avian species, some differences in toxicokinetics have been observed. All the data reviewed suggest that the toxicokinetics of fusariotoxins in avian species differs from those in mammals, and that variations among the avian species themselves should be assessed.

  10. Report to Congress on abnormal occurrences, October--December 1992

    International Nuclear Information System (INIS)

    1993-03-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from October 1 through December 31, 1992. There are two abnormal occurrences at nuclear power plants and six abnormal occurrences involving medical misadministration (all therapeutic) at NRC-licensed facilities discussed in this report. No abnormal occurrences were reported by the NRC's Agreement States. The report also contains information updating three previously reported abnormal occurrences

  11. Report to congress on abnormal occurrences: January--March 1992

    International Nuclear Information System (INIS)

    1992-07-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to congress. This report covers the period from January 1 through March 31, 1992. The abnormal occurrences involving medical therapy misadministrations at NRC-licensed facilities are discussed in this report. There were no abnormal occurrences at a nuclear power plant, and none were reported by NRC's Agreement States. The report also contains information updating some previously reported abnormal occurrences

  12. A probabilistic model for snow avalanche occurrence

    Science.gov (United States)

    Perona, P.; Miescher, A.; Porporato, A.

    2009-04-01

    Avalanche hazard forecasting is an important issue in relation to the protection of urbanized environments, ski resorts and of ski-touring alpinists. A critical point is to predict the conditions that trigger the snow mass instability determining the onset and the size of avalanches. On steep terrains the risk of avalanches is known to be related to preceding consistent snowfall events and to subsequent changes in the local climatic conditions. Regression analysis has shown that avalanche occurrence indeed correlates to the amount of snow fallen in consecutive three snowing days and to the state of the settled snow at the ground. Moreover, since different type of avalanches may occur as a result of the interactions of different factors, the process of snow avalanche formation is inherently complex and with some degree of unpredictability. For this reason, although several models assess the risk of avalanche by accounting for all the involved processes with a great detail, a high margin of uncertainty invariably remains. In this work, we explicitly describe such an unpredictable behaviour with an intrinsic noise affecting the processes leading snow instability. Eventually, this sets the basis for a minimalist stochastic model, which allows us to investigate the avalanche dynamics and its statistical properties. We employ a continuous time process with stochastic jumps (snowfalls), deterministic decay (snowmelt and compaction) and state dependent avalanche occurrence (renewals) as a minimalist model for the determination of avalanche size and related intertime occurrence. The physics leading to avalanches is simplified to the extent where only meteorological data and terrain data are necessary to estimate avalanche danger. We explore the analytical formulation of the process and the properties of the probability density function of the avalanche process variables. We also discuss what is the probabilistic link between avalanche size and preceding snowfall event and

  13. Crossing seas and occurrence of rogue waves

    Science.gov (United States)

    Bitner-Gregersen, Elzbieta; Toffoli, Alessandro

    2017-04-01

    The study is addressing crossing wave systems which may lead to formation of rogue waves. Onorato et al. (2006, 2010) have shown using the Nonlinear Schr?dringer (NLS) equations that the modulational instability and rogue waves can be triggered by a peculiar form of directional sea state, where two identical, crossing, narrow-banded random wave systems interact with each other. Such results have been underpinned by numerical simulations of the Euler equations solved with a Higher Order Spectral Method (HOSM) and experimental observations (Toffoli et al., 2011). They substantiate a dependence of the angle between the mean directions of propagation of the two crossing wave systems, with a maximum rogue wave probability for angles of approximately 40 degrees. Such an unusual sea state of two almost identical wave systems (approximately the same significant wave height and mean frequency) with high steepness and different directions was observed during the accident to the cruise ship Louis Majesty (Cavaleri et al. 2012). Occurrence of wind sea and swell having almost the same spectral period and significant wave height and crossing at the angle 40o low and intermediate wave conditions. They have not been found in a location off coast of Australia and Nigeria. There are some indications that in the future climate we may expect an increase number of occurrence of rogue-prone crossing sea states in some ocean regions An adopted partitioning procedure of a wave spectrum will impact the results. References Bitner-Gregersen, E.M. and Toffoli, A., 2014. Probability of occurrence of rogue sea states and consequences for design of marine structures. Special Issue of Ocean Dynamics, ISSN 1616-7341, 64(10), DOI 10.1007/s10236-014-0753-2. Cavaleri, L., Bertotti, L., Torrisi, L. Bitner-Gregersen, E., Serio, M. and Onorato, M., 2012. Rogue Waves in Crossing Seas: The Louis Majesty accident. J. Geophysical Research, 117, C00J10, doi:10.1029/2012JC007923 Onorato, M., A. Osborne, A

  14. Occurrence of ochratoxin A in commodities and processed food - A review of EU occurrence data

    DEFF Research Database (Denmark)

    Jørgensen, Kevin

    2005-01-01

    A brief review on the occurrence of ochratoxin A in commodities and processed food on the European market (meat and meat products, cereal and cereal products, spices, beer, cocoa and derived products, coffee, wine, dried vine fruits, grape juice) is given in an historical perspective based on two...

  15. Integration of species persistence, costs and conflicts

    DEFF Research Database (Denmark)

    Strange, Niels; Theilade, Ida; Thea, So

    2007-01-01

    -industries, encroachment, illegal logging, over-harvesting and forest fire as well as the use of chemicals during war. The purpose of the paper is to: (i) apply reserve selection methods to design more robust conservation networks when knowledge of species occurrence is incomplete and habitat is threatened, and (ii...

  16. Using Benchmarking To Strengthen the Assessment of Persistence.

    Science.gov (United States)

    McLachlan, Michael S; Zou, Hongyan; Gouin, Todd

    2017-01-03

    Chemical persistence is a key property for assessing chemical risk and chemical hazard. Current methods for evaluating persistence are based on laboratory tests. The relationship between the laboratory based estimates and persistence in the environment is often unclear, in which case the current methods for evaluating persistence can be questioned. Chemical benchmarking opens new possibilities to measure persistence in the field. In this paper we explore how the benchmarking approach can be applied in both the laboratory and the field to deepen our understanding of chemical persistence in the environment and create a firmer scientific basis for laboratory to field extrapolation of persistence test results.

  17. Towards a Formal Occurrence Logic based on Predicate Logic

    DEFF Research Database (Denmark)

    Badie, Farshad; Götzsche, Hans

    2015-01-01

    In this discussion we will concentrate on the main characteristics of an alternative kind of logic invented by Hans Götzsche: Occurrence Logic, which is not based on truth functionality. Our approach is based on temporal logic developed and elaborated by A. N. Prior. We will focus on characterising...... argumentation based on formal Occurrence Logic concerning events and occurrences, and illustrate the relations between Predicate Logic and Occurrence Logic. The relationships (and dependencies) is conducive to an approach that can analyse the occurrences of ”logical statements based on different logical...... principles” in different moments. We will also conclude that the elaborated Götzsche’s Occurrence Logic could be able to direct us to a truth-functional independent computer-based logic for analysing argumentation based on events and occurrences....

  18. Geospatial Analysis Application to Forecast Wildfire Occurrences in South Carolina

    Directory of Open Access Journals (Sweden)

    Stephen L. Sperry

    2012-05-01

    Full Text Available Wildfire occurrence and intensity have increased over the last few decades and, at times, have been national news. Wildfire occurrence is somewhat predictable based on physical factors like meteorological conditions, fuel loads, and vegetation dynamics. Socioeconomic factors have been not been widely used in wildfire occurrence models. We used a geospatial (or geographical information system analysis approach to identify socioeconomic variables that contribute to wildfire occurrence. Key variables considered were population change, population density, poverty rate, educational level, geographic mobility, and road density (transportation network. Hot spot analysis was the primary research tool. Wildfire occurrence seemed to be positively related to low population densities, low levels of population change, high poverty rate, low educational attainment level, and low road density. Obviously, some of these variables are correlated and this is a complex problem. However, socioeconomic variables appeared to contribute to wildfire occurrence and should be considered in development of wildfire occurrence forecasting models.

  19. Occurrence of keratinophilic fungi on Indian birds.

    Science.gov (United States)

    Dixit, A K; Kushwaha, R K

    1991-01-01

    Keratinophilic fungi were isolated from feathers of most common Indian birds, viz. domestic chicken (Gallus domesticus), domestic pigeon (Columba livia), house sparrow (Passer domesticus), house crow (Corvus splendens), duck (Anas sp.), rose-ringed parakeet (Psittacula krameri). Out of 87 birds, 58 yielded 4 keratinophilic fungal genera representing 13 fungal species and one sterile mycelium. The isolated fungi were cultured on Sabouraud's dextrose agar at 28 +/- 2 degrees C. Chrysosporium species were isolated on most of the birds. Chrysosporium lucknowense and Chrysosporium tropicum were the most common fungal species associated with these Indian birds. Maximum occurrence of fungi (47%) was recorded on domestic chickens and the least number of keratinophilic fungi was isolated from the domestic pigeon and duck. The average number of fungi per bird was found to be the 0.44.

  20. Radioactive mineral occurrences in the Bancroft area

    Energy Technology Data Exchange (ETDEWEB)

    Satterly, J

    1958-12-31

    The report summarizes three years of field work conducted in the Bancroft area investigating occurrences of radioactive minerals, and also includes accounts of properties in the area for which drill logs and survey reports have been filed. It begins with a history of exploration and development of radioactive mineral deposits in the area, a review of the area`s general geology (Grenville metasediments, plutonic rocks), and general descriptions of the types of radioactive mineral deposits found in the area (deposits in granitic and syenitic bodies, metasomatic deposits in limy rocks, hydrothermal deposits). It also describes the mineralogy of radioactive minerals found in the area and the Geiger counter technique used in the investigation. The bulk of the report consists of descriptions of radioactive mineral properties and mine workings, containing (where available) information on exploration history, general and economic geology, and production.

  1. Lichen explants and natural occurrence of lichens

    Energy Technology Data Exchange (ETDEWEB)

    Kirschbaum, A; Klee, R

    1971-01-01

    Studies with lichen explants and with naturally occurring lichens, conducted in the Lower Main region in West Germany within the framework of an air hydgienic and meteorologic model study of that region, are described. Parmelia physodes explants from oak trees growing in nonpolluted areas were exposed in polluted areas, such as in an industrial area, an airport, a petroleum refinery, and near a large chemical plant. The degree of air pollution in the exposure site was evaluated by the degree of the lichen damage in seven grades. The large-scale average distribution of air pollution in the survey area was studied by surveying the natural occurrence of lichen species on 10 apple trees in area units of 6.25 sq km each. The lichen explant and lichen survey methods compared by the study of naturally occurring lichens were near the exposure site of lichen explants.

  2. Diptera, Drosophilidae: historical occurrence in Brazil

    Directory of Open Access Journals (Sweden)

    Valente, V. L. S.

    2008-01-01

    Full Text Available This study presents a literature review of Drosophilidae (Diptera species occurrence in Brazil. The number of speciesrecorded is 304, with Drosophila being the genus with the greatest number of species, followed by Zygothrica,Hirtodrosophila and Diathoneura, which belong to the Drosophilinae subfamily. Drosophila was shown to be the mostinvestigated taxon in the family, with the best resolved species distribution. The low number of records of species fromother genera indicates the paucity of studies specifically designed to investigate these species. Records of species forsome regions of the country like the north and northeast, as well as for some biomes like Caatinga, Pantanal and thePampas, are likewise rare. Apart from the banana bait, different collection methods may be necessary, like thecollection at other oviposition resources, the use of baits other than fermenting fruit, and the adoption of samplingapproaches that do not use baits.

  3. Occurrence of Endoparasites in Indigenous Zambian Dogs

    Directory of Open Access Journals (Sweden)

    Bruce-Miller M.

    2016-09-01

    Full Text Available This study was conducted in the country of Zambia, Southern Africa, to investigate the occurrence of endo-parasites in indigenous Zambian dogs. Faecal samples were collected from 41 indigenous Zambian dogs from different areas of the Mbabala region in the Southern province of Zambia during the “hot wet” season, although at the time that the samples were collected, the country was experiencing a drought. Faecal samples were analysed using the concentration flotation method with zinc sulphate for the determination of the presence of gastrointestinal parasites. The most prevalent parasites were species from the family Ancylostomatidae (65.0 % infection rate which followed by: Isospora canis (9.8 %, Dipylidium caninum (4.8 %, and Toxascaris leonina (2.4 %. There were in addition, two cases of co-infections with the family Ancylostomatidae and D. caninum, as well as the family Ancylostomatidae and I. canis.

  4. Occurrence of Surface Water Contaminations: An Overview

    Science.gov (United States)

    Shahabudin, M. M.; Musa, S.

    2018-04-01

    Water is a part of our life and needed by all organisms. As time goes by, the needs by human increased transforming water quality into bad conditions. Surface water contaminated in various ways which is pointed sources and non-pointed sources. Pointed sources means the source are distinguished from the source such from drains or factory but the non-pointed always occurred in mixed of elements of pollutants. This paper is reviewing the occurrence of the contaminations with effects that occurred around us. Pollutant factors from natural or anthropology factors such nutrients, pathogens, and chemical elements contributed to contaminations. Most of the effects from contaminated surface water contributed to the public health effects also to the environments.

  5. Occurrence of Parthenogenesis in Potato Tuber Moth

    Science.gov (United States)

    Liu, Yan; Hu, Chun-Hua; Wang, Chun-Ya; Xiong, Yan; Li, Zong-Kai; Xiao, Chun

    2018-01-01

    Abstract Parthenogenesis, a natural form of asexual reproduction produced from unfertilized eggs, occurs in many insects in Hemiptera and Hymenoptera, but very rarely in Lepidoptera. The current study aimed to test the larval density dependent occurrence of parthenogenesis in potato tuber moth, Phthorimaea operculella (Zeller; Lepidoptera: Gelechiidae) under laboratory conditions. More than 10% of females out of 25 tested females that developed from the high larval density treatment at 45 larvae per tuber were capable to reproduce asexually. Both male and female offspring were produced parthenogenetically. The sexually reproductive offspring of a laboratory parthenogenetic population had a lower egg hatch rate, shorter larval stage, and shorter male life span when compared with the non-parthenogenetic population. This suggests that the sexually reproductive offspring of parthenogenetic population have a decreased overall fitness compared to the sexually reproductive offspring of non-parthenogenetic population.

  6. Occurrence and biosynthesis of carotenoids in phytoplankton.

    Science.gov (United States)

    Huang, Jim Junhui; Lin, Shaoling; Xu, Wenwen; Cheung, Peter Chi Keung

    2017-09-01

    Naturally occurring carotenoids are important sources of antioxidants, anti-cancer compounds and anti-inflammatory agents and there is thus considerable market demand for their pharmaceutical applications. Carotenoids are widely distributed in marine and freshwater organisms including microalgae, phytoplankton, crustaceans and fish, as well as in terrestrial plants and birds. Recently, phytoplankton-derived carotenoids have received much attention due to their abundance, rapid rate of biosynthesis and unique composition. The carotenoids that accumulate in particular phytoplankton phyla are synthesized by specific enzymes and play unique physiological roles. This review focuses on studies related to the occurrence of carotenoids in different phytoplankton phyla and the molecular aspects of their biosynthesis. Recent biotechnological advances in the isolation and characterization of some representative carotenoid synthases in phytoplankton are also discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. The occurrence of Salmonella in airline meals.

    Science.gov (United States)

    Hatakka, M; Asplund, K

    1993-01-01

    The occurrence of Salmonella in airline meals was studied in 1989-1992. Samples were collected from flight kitchens in 29 countries. The material consisted of 400 cold dishes and 1,288 hot dishes as well as salads, cheese plates and deserts. Total number of samples was 2211. Salmonella spp. were isolated from 6 samples; 1 contaminated sample was a cold dish prepared in Bangkok, 1 was a hot dish prepared in Mombasa and the remaining 4 contaminated samples were hot dishes prepared within one week in Beijing. The isolated serotypes were S. ohio, S. manchester and S. braenderup. The contaminated cold dish prepared by a flight kitchen in Bangkok was found to be connected with a Salmonella outbreak which occurred in Finland in 1990. Cold airline dishes containing food of animal origin seems to be more risky as a source of Salmonella infections among airline passengers.

  8. Nonstationarity in the occurrence rate of floods in the Tarim River basin, China, and related impacts of climate indices

    Science.gov (United States)

    Gu, Xihui; Zhang, Qiang; Singh, Vijay P.; Chen, Xi; Liu, Lin

    2016-07-01

    Amplification of floods in the Xinjiang, China, has been observed, but reports on their changing properties and underlying mechanisms are not available. In this study, occurrence rates of floods in the Tarim River basin, the largest inland arid river basin in China, were analyzed using the Kernel density estimation technique and bootstrap resampling method. Also analyzed were the occurrence rates of precipitation extremes using the POT (Peak over Threshold)-based sampling method. Both stationary and non-stationary models were developed using GAMLSS (Generalized Additive Models for Location, Scale and Shape) to model flood frequency with time, climate index, precipitation and temperature as major predictors. Results indicated: (1) two periods with increasing occurrence of floods, i.e., the late 1960s and the late 1990s with considerable fluctuations around 2-3 flood events during time intervals between the late 1960s and the late 1990s; (2) changes in the occurrence rates of floods were subject to nonstationarity. A persistent increase of flood frequency and magnitude was observed during the 1990s and reached a peak value; (3) AMO (Atlantic Multidecadal Oscillation) and AO (Atlantic Oscillation) in winter were the key influencing climate indices impacting the occurrence rates of floods. However, NAO (North Atlantic Oscillation) and SOI (South Oscillation Index) are two principle factors that influence the occurrence rates of regional floods. The AIC (Akaike Information Criterion) values indicated that compared to the influence of climate indices, occurrence rates of floods seemed to be more sensitive to temperature and precipitation changes. Results of this study are important for flood management and development of mitigation measures.

  9. The Enigmatic Persistence of Anorexia Nervosa

    Science.gov (United States)

    Walsh, B. Timothy

    2014-01-01

    Objective In this review, based on recent advances in cognitive neuroscience, the author presents a formulation in which the marked persistence of anorexia nervosa can be usefully understood as a well-ingrained maladaptive habit. Method The author reviewed the relevant literature on the development and course of anorexia nervosa and interpreted critical features in light of developments in cognitive neuroscience. Results Anorexia nervosa is a well characterized disorder with remarkable persistence both across history and among affected individuals. Food restriction, the salient behavioral feature of the disorder, often begins innocently but gradually takes on a life of its own. Over time, it becomes highly entrenched and resistant to change through either psychological or pharmacological treatment. Cognitive neuroscience has described two related but distinct processes that underlie the acquisition of new patterns of behavior, namely, action-outcome and stimulus-response learning. It is likely that both processes are engaged in the development of anorexia nervosa and that stimulus-response learning (that is, habit formation) is critical to the persistence of the dieting behavior. Conclusions The formulation of the dieting behavior characteristic of anorexia nervosa as a well-entrenched habit provides a basis for understanding the striking persistence of this disorder. This model helps explain the resistance of anorexia nervosa to interventions that have established efficacy in related disorders and implies that addressing the dieting behavior is critical, especially early in the course of the illness, before it has become ingrained. PMID:23429750

  10. Nitrogen uptake dynamics of a persistent cyanobacterium ...

    African Journals Online (AJOL)

    Worldwide, persistent cyanobacterial blooms are becoming more frequent and are often associated with effects of global climate change. In June 2009, a widespread bloom of the unicellular cyanobacterium, Cyanothece sp., appeared in North Lake and False Bay of Lake St Lucia – a large (360 km2) estuarine lake system ...

  11. Persistent Functional Languages: Toward Functional Relational Databases

    NARCIS (Netherlands)

    Wevers, L.

    2014-01-01

    Functional languages provide new approaches to concurrency control, based on techniques such as lazy evaluation and memoization. We have designed and implemented a persistent functional language based on these ideas, which we plan to use for the implementation of a relational database system. With

  12. Persistent pain after mastectomy with reconstruction.

    LENUS (Irish Health Repository)

    Hickey, Oonagh T

    2011-09-01

    To determine the prevalence of persistent postsurgical pain (PPSP) and its influence on functional status, and to examine associations between PPSP and single nucleotide polymorphisms of the catechol-O-methyltransferase (COMT) gene and the guanosine triphosphate cyclohydrolase 1 (GCH1) gene following mastectomy and reconstruction.

  13. Persistent ovarian masses and pregnancy outcomes.

    Science.gov (United States)

    Goh, William A; Rincon, Monica; Bohrer, Justin; Tolosa, Jorge E; Sohaey, Roya; Riaño, Rene; Davis, James; Zalud, Ivica

    2013-07-01

    To determine if persistent ovarian masses in pregnancy are associated with increased adverse outcomes. This is a retrospective cohort of 126 pregnant women with a persistent ovarian mass measuring 5 cm or greater who delivered at two university hospitals between 2001 and 2009. Maternal outcomes included gestational age (GA) at diagnosis, delivery and surgery as well as miscarriage, preterm birth (PTB), ovarian torsion and hospital admission for pain. Neonatal outcomes included birth weight, respiratory distress syndrome (RDS), intra-ventricular hemorrhage (IVH), death and sepsis. A total of 1225 ovarian masses were identified (4.9%) in 24,868 patients. A persistent ovarian mass was found in 0.7%. Average GA at diagnosis was 17.8 weeks. Miscarriage rate was 3.3%. Average GA at delivery was 37.9 weeks. Of the patients, 8.5% had ovarian torsion, 10.3% had admission for pain and 9.3% had PTBs. The mean cesarean delivery rate was 46.3%. The average neonatal weight was 3273 g. There was one neonatal death in this cohort. The rate of RDS was 2.8%, IVH 0.9% and neonatal sepsis 1.9%. The most common surgical pathologic diagnosis was dermoids (37.6%). No overt malignancies were seen. A persistent ovarian mass in pregnancy does not confer an increased risk of adverse pregnancy outcomes.

  14. Persistence of Change: Fume Hood Campaign Lessons

    Science.gov (United States)

    Feder, Elah; Robinson, Jennifer; Wakefield, Sarah

    2012-01-01

    Purpose: Sustainability initiatives typically operate for a limited time period, but it is often unclear whether they have lasting effects. The purpose of this paper is to examine a laboratory fume hood campaign, in order to identify factors that might contribute or detract from long-term change persistence. Design/methodology/approach: The…

  15. Treatment of persistent pain from torture

    DEFF Research Database (Denmark)

    Williams, Amanda C de C; Amris, Kirstine

    2017-01-01

    the nature of persistent pain means that pain is largely overlooked and untreated in torture survivors. We carried out a systematic review on treatments for pain from torture, but found few studies and little use of current understanding and evidence. We discuss this in the context of treating pain...

  16. Reserve design to maximize species persistence

    Science.gov (United States)

    Robert G. Haight; Laurel E. Travis

    2008-01-01

    We develop a reserve design strategy to maximize the probability of species persistence predicted by a stochastic, individual-based, metapopulation model. Because the population model does not fit exact optimization procedures, our strategy involves deriving promising solutions from theory, obtaining promising solutions from a simulation optimization heuristic, and...

  17. Retrospective review of neonates with persistent pulmonary ...

    African Journals Online (AJOL)

    Persistent pulmonary hypertension of the newborn (PPHN) is a clinical condition characterised by severe respiratory failure and hypoxaemia.[1] Its incidence is estimated at around 2 per 1 000 live births worldwide and it is associated with a high morbidity and mortality.[2,3] Despite the progress in treating PPHN, it remains a.

  18. A Neonate with persistent hypoglycemia and seizures.

    African Journals Online (AJOL)

    MBY

    disorder was diagnosed and managed with limited success as the episodes hydroglycemic seizures persisted. ... the presence of hyperinsulinemia as the cause of the hypoglycemic dependent seizures. Case Presentation. A three day old girl was admitted to the neonatal .... the Prader-Willi syndrome, has been reported.

  19. Persistent Pain and Sensory Abnormalities after Abdominoplasty

    DEFF Research Database (Denmark)

    Presman, Benjamin; Finnerup, Kenneth; Andresen, Sven Robert

    2015-01-01

    and characteristics of persistent pain after abdominoplasty, which is one of the most frequent cosmetic surgical procedures. METHODS: In September 2014, a link to a web-based questionnaire was mailed to 217 patients who had undergone abdominoplasty between 2006 and 2014 at the Department of Plastic Surgery, Aalborg...

  20. The Myth of Persistence of Vision Revisited.

    Science.gov (United States)

    Anderson, Joseph; Anderson, Barbara

    1993-01-01

    Argues that "persistence of vision" myth (the succession of still images perceived as continuous motion) has a place in the history of film scholarship but can no longer be given currency in film theory. Suggests replacement of the concept of the passive viewer implied by the myth by an enlightened understanding of how viewers actually…

  1. Forecasting autoregressive time series under changing persistence

    DEFF Research Database (Denmark)

    Kruse, Robinson

    Changing persistence in time series models means that a structural change from nonstationarity to stationarity or vice versa occurs over time. Such a change has important implications for forecasting, as negligence may lead to inaccurate model predictions. This paper derives generally applicable...

  2. Persistence Modeling for Assessing Marketing Strategy Performance

    NARCIS (Netherlands)

    M.G. Dekimpe (Marnik); D.M. Hanssens (Dominique)

    2003-01-01

    textabstractThe question of long-run market response lies at the heart of any marketing strategy that tries to create a sustainable competitive advantage for the firm or brand. A key challenge, however, is that only short-run results of marketing actions are readily observable. Persistence modeling

  3. Persistent trophoblast disease following partial molar pregnancy.

    NARCIS (Netherlands)

    Wielsma, S.; Kerkmeijer, L.G.W.; Bekkers, R.L.M.; Pyman, J.; Tan, J.; Quinn, M.

    2006-01-01

    OBJECTIVE: Human chorionic gonadotrophin (hCG) follow-up data were analysed retrospectively in all patients registered in the Hydatidiform Mole Registry at the Royal Women's Hospital, Melbourne from January 1992 to January 2001 to determine the risk of persistent trophoblast disease following

  4. Intermediates, Catalysts, Persistence, and Boundary Steady States

    DEFF Research Database (Denmark)

    Marcondes de Freitas, Michael; Feliu, Elisenda; Wiuf, Carsten

    2017-01-01

    networks without breaking known necessary or sufficient conditions for persistence, by iteratively removing socalled intermediates and catalysts from the network. The procedures are easy to apply and, in many cases, lead to highly simplified network structures, such as monomolecular networks. For specific...

  5. Diversity of Lactase Persistence Alleles in Ethiopia

    DEFF Research Database (Denmark)

    Jones, BL; Raga, TO; Liebert, Anke

    2013-01-01

    The persistent expression of lactase into adulthood in humans is a recent genetic adaptation that allows the consumption of milk from other mammals after weaning. In Europe, a single allele (−13910∗T, rs4988235) in an upstream region that acts as an enhancer to the expression of the lactase gene ...

  6. Hyperthyroidism as a cause of persistent vomiting.

    NARCIS (Netherlands)

    Hoogendoorn, E.H.; Cools, B.M.

    2004-01-01

    A 32-year-old woman presented with persistent vomiting, epigastric pain and weight loss. A sinus tachycardia was the clue to the diagnosis of hyperthyroidism due to Graves' disease. On treatment with propylthiouracil and a beta-blocking agent, her symptoms resolved within one day, even though her

  7. Ethnic Differences in Persistence with COPD Medications

    DEFF Research Database (Denmark)

    Hu, Yusun; Cantarero-Arévalo, Lourdes; Frølich, Anne

    2017-01-01

    BACKGROUND: Long-acting bronchodilators (LABDs) are recommended as a first-line maintenance therapy in patients with moderate or severe chronic obstructive pulmonary disease (COPD). The aim of the study was to explore potential ethnic differences in persistence with LABD in COPD patients. METHODS...

  8. Novel protocol for persister cells isolation.

    Directory of Open Access Journals (Sweden)

    Silvia J Cañas-Duarte

    Full Text Available Bacterial persistence, where a fraction of a population presents a transient resistance to bactericidal substances, has great medical importance due to its relation with the appearance of antibiotic resistances and untreatable bacterial chronic infections. The mechanisms behind this phenomenon remain largely unknown in spite of recent advances, in great part because of the difficulty in isolating the very small fraction of the population that is in this state at any given time. Current protocols for persister isolation have resulted in possible biases because of the induction of this state by the protocol itself. Here we present a novel protocol that allows rapid isolation of persister cells both from exponential and stationary phase. Moreover, it is capable of differentiating between type I and type II persister cells, which should allow the field to move beyond its current state of studying only one type. While this protocol prompts a revision of many of the current results, it should greatly facilitate further advances in the field.

  9. Persistence of Value-Driven Attentional Capture

    Science.gov (United States)

    Anderson, Brian A.; Yantis, Steven

    2013-01-01

    Stimuli that have previously been associated with the delivery of reward involuntarily capture attention when presented as unrewarded and task-irrelevant distractors in a subsequent visual search task. It is unknown how long such effects of reward learning on attention persist. One possibility is that value-driven attentional biases are plastic…

  10. Retrospective review of neonates with persistent pulmonary ...

    African Journals Online (AJOL)

    Background. Persistent pulmonary hypertension of the newborn (PPHN) is a clinical syndrome characterised by high pulmonary pressures, low systemic pressures and severe hypoxaemia due to circulation transition failure after birth. Objective. To determine the incidence of and describe the risk factors, infant ...

  11. Judgment of facial expressions and depression persistence

    NARCIS (Netherlands)

    Hale, WW

    1998-01-01

    In research it has been demonstrated that cognitive and interpersonal processes play significant roles in depression development and persistence. The judgment of emotions displayed in facial expressions by depressed patients allows for a better understanding of these processes. In this study, 48

  12. Persistence of environmental DNA in freshwater ecosystems.

    Directory of Open Access Journals (Sweden)

    Tony Dejean

    Full Text Available The precise knowledge of species distribution is a key step in conservation biology. However, species detection can be extremely difficult in many environments, specific life stages and in populations at very low density. The aim of this study was to improve the knowledge on DNA persistence in water in order to confirm the presence of the focus species in freshwater ecosystems. Aquatic vertebrates (fish: Siberian sturgeon and amphibian: Bullfrog tadpoles were used as target species. In control conditions (tanks and in the field (ponds, the DNA detectability decreases with time after the removal of the species source of DNA. DNA was detectable for less than one month in both conditions. The density of individuals also influences the dynamics of DNA detectability in water samples. The dynamics of detectability reflects the persistence of DNA fragments in freshwater ecosystems. The short time persistence of detectable amounts of DNA opens perspectives in conservation biology, by allowing access to the presence or absence of species e.g. rare, secretive, potentially invasive, or at low density. This knowledge of DNA persistence will greatly influence planning of biodiversity inventories and biosecurity surveys.

  13. Occurrence of transformation products in the environment

    Science.gov (United States)

    Kolpin, Dana W.; Battaglin, William A.; Conn, Kathleen E.; Furlong, Edward T.; Glassmeyer, Susan T.; Kalkhoff, Stephen J.; Meyer, Michael T.; Schnoebelen, Douglas J.; Boxall, Alistair B.A.

    2009-01-01

    Historically, most environmental occurrence research has focused on the parent compounds of organic contaminants. Research, however, has documented that the environmental transport of chemicals, such as pesticides and emerging contaminants, are substantially underestimated if transformation products are not considered. Although most examples described herein were drawn from research conducted by the U.S. Geological Survey, such results are generally reflective of those found in other parts of the world. Results from a study of 51 streams in the Midwestern United States found that transformation products were seven of the ten most frequently detected pesticide compounds in late spring runoff (after application of pre-emergent herbicides), and nine of the ten most frequently detected compounds in fall season runoff (during and after harvest). In fact, 70% of the total herbicide concentration in water from the Mississippi River Basin was from transformation products. Results from a study of 86 municipal wells in Iowa found the frequency of detection increased from 17%, when pesticide parent compounds were considered, to 53%, when both parents and transformation products were considered. Transformation products were 12 of the 15 most frequently detected compounds for this groundwater study. Although studies on transformation products of synthetic organic compounds other than pesticides are not as common, wastewater treatment plant discharges have repeatedly been shown to contribute such transformation products to streams. In addition, select detergent transformation products have been commonly found in solid waste in the 1000's mg/kg. These findings and many others document that transformation products must be considered to fully assess the potential environmental occurrence of chemical contaminants and their transport and fate in various compartments of the hydrologic system. ?? 2008 Springer-Verlag Berlin Heidelberg.

  14. Fracture occurrence from radionuclides in the skeleton

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, R.D.; Taylor, G.N.; Miller, S.C.

    2000-06-01

    Because skeletal fractures were an important finding among persons contaminated with {sup 226}Ra, experience with fractures among dogs in the colony was summarized to determine the projected significance for persons contaminated with bone-seeking radionuclides. Comparison by Fisher's Exact Test of lifetime fracture occurrence in the skeletons of beagles injected as young adults suggested that for animals given {sup 226}Ra, {sup 228}Ra, {sup 228}Th, or {sup 239}Pu citrate, there was probably an excess over controls in fractures of the ribs, leg bones, spinous processes, and pelvis (os coxae) plus the mandible for dogs given {sup 226}Ra and the scapulae for dogs given {sup 228}Ra or 228 Th. Regression analysis indicated that significantly elevated fracture occurrence was especially notable at the higher radiation doses, at about 50 Gy average skeletal dose for {sup 239}Pu, 140 Gy for {sup 226}Ra, about 40 Gy for {sup 228}Ra, and more than 15 Gy for {sup 228}Th. The average number of fractures per dog was significantly elevated over that noted in controls for the highest radiation doses of {sup 239}Pu and {sup 226}Ra and for the higher doses of {sup 228}Ra and {sup 228}Th. For those dogs given {sup 90}Sr citrate, there was virtually no important difference from control beagles not given radionuclides, even at group mean cumulative skeletal radiation doses up to 101 Gy. Because of a large proportion of dogs with fractures that died with bone malignancy (even at dosage levels lower than those exhibiting an excess average number of fractures per dog), they conclude that fracture would not be an important endpoint at lower levels of plutonium contamination in humans such as would be expected to occur from occupational or environmental exposure.

  15. Occurrence and average behavior of pulsating aurora

    Science.gov (United States)

    Partamies, N.; Whiter, D.; Kadokura, A.; Kauristie, K.; Nesse Tyssøy, H.; Massetti, S.; Stauning, P.; Raita, T.

    2017-05-01

    Motivated by recent event studies and modeling efforts on pulsating aurora, which conclude that the precipitation energy during these events is high enough to cause significant chemical changes in the mesosphere, this study looks for the bulk behavior of auroral pulsations. Based on about 400 pulsating aurora events, we outline the typical duration, geomagnetic conditions, and change in the peak emission height for the events. We show that the auroral peak emission height for both green and blue emission decreases by about 8 km at the start of the pulsating aurora interval. This brings the hardest 10% of the electrons down to about 90 km altitude. The median duration of pulsating aurora is about 1.4 h. This value is a conservative estimate since in many cases the end of event is limited by the end of auroral imaging for the night or the aurora drifting out of the camera field of view. The longest durations of auroral pulsations are observed during events which start within the substorm recovery phases. As a result, the geomagnetic indices are not able to describe pulsating aurora. Simultaneous Antarctic auroral images were found for 10 pulsating aurora events. In eight cases auroral pulsations were seen in the southern hemispheric data as well, suggesting an equatorial precipitation source and a frequent interhemispheric occurrence. The long lifetimes of pulsating aurora, their interhemispheric occurrence, and the relatively high-precipitation energies make this type of aurora an effective energy deposition process which is easy to identify from the ground-based image data.

  16. Persistence of Mycoplasma genitalium following azithromycin therapy.

    Directory of Open Access Journals (Sweden)

    Catriona S Bradshaw

    Full Text Available BACKGROUND: To determine clinical outcomes and cure rates for M.genitalium genital infection in men and women following azithromycin 1 g. METHODOLOGY: Patients attending Melbourne Sexual Health Centre between March 2005 and November 2007 with urethritis/epididymitis, cervicitis/pelvic inflammatory disease and sexual contacts of M.genitalium were tested for M.genitalium by polymerase chain reaction (PCR. M.genitalium-infection was treated with 1 g of azithromycin and a test-of-cure (toc was performed one month post-azithromycin. Response to azithromycin, and response to moxifloxacin (400 mg daily for 10 days in individuals with persistent infection post-azithromycin, was determined. PRINCIPAL FINDINGS: Of 1538 males and 313 females tested, 161 males (11% and 30 females (10% were infected with M.genitalium. A toc was available on 131 (69% infected individuals (median = 36 days [range 12-373]. Of 120 individuals prescribed azithromycin only pre-toc, M.genitalium was eradicated in 101 (84%, 95% confidence intervals [CI]: 77-90% and persisted in 19 (16%, 95% CI: 10-23%. Eleven individuals with persistent infection (9%, 95% CI: 5-15% had no risk of reinfection from untreated-partners, while eight (7%, 95% CI: 3-12% may have been at risk of reinfection from doxycycline-treated or untreated-partners. Moxifloxacin was effective in eradicating persistent infection in all cases not responding to azithromycin. Patients with persistent-M.genitalium were more likely to experience persistent symptoms (91%, compared to patients in whom M.genitalium was eradicated (17%, p<0.0001. CONCLUSION: Use of azithromycin 1 g in M.genitalium-infected patients was associated with unacceptable rates of persistent infection, which was eradicated with moxifloxacin. These findings highlight the importance of follow-up in M.genitalium-infected patients prescribed azithromycin, and the need to monitor for the development of resistance. Research to determine optimal first and

  17. Multiscale Persistent Functions for Biomolecular Structure Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Kelin [Nanyang Technological University (Singapore). Division of Mathematical Sciences, School of Physical, Mathematical Sciences and School of Biological Sciences; Li, Zhiming [Central China Normal University, Wuhan (China). Key Laboratory of Quark and Lepton Physics (MOE) and Institute of Particle Physics; Mu, Lin [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computer Science and Mathematics Division

    2017-11-02

    Here in this paper, we introduce multiscale persistent functions for biomolecular structure characterization. The essential idea is to combine our multiscale rigidity functions (MRFs) with persistent homology analysis, so as to construct a series of multiscale persistent functions, particularly multiscale persistent entropies, for structure characterization. To clarify the fundamental idea of our method, the multiscale persistent entropy (MPE) model is discussed in great detail. Mathematically, unlike the previous persistent entropy (Chintakunta et al. in Pattern Recognit 48(2):391–401, 2015; Merelli et al. in Entropy 17(10):6872–6892, 2015; Rucco et al. in: Proceedings of ECCS 2014, Springer, pp 117–128, 2016), a special resolution parameter is incorporated into our model. Various scales can be achieved by tuning its value. Physically, our MPE can be used in conformational entropy evaluation. More specifically, it is found that our method incorporates in it a natural classification scheme. This is achieved through a density filtration of an MRF built from angular distributions. To further validate our model, a systematical comparison with the traditional entropy evaluation model is done. Additionally, it is found that our model is able to preserve the intrinsic topological features of biomolecular data much better than traditional approaches, particularly for resolutions in the intermediate range. Moreover, by comparing with traditional entropies from various grid sizes, bond angle-based methods and a persistent homology-based support vector machine method (Cang et al. in Mol Based Math Biol 3:140–162, 2015), we find that our MPE method gives the best results in terms of average true positive rate in a classic protein structure classification test. More interestingly, all-alpha and all-beta protein classes can be clearly separated from each other with zero error only in our model. Finally, a special protein structure index (PSI) is proposed, for the first

  18. Persistence of undergraduate women in STEM fields

    Science.gov (United States)

    Pedone, Maggie Helene

    The underrepresentation of women in science, technology, engineering, and mathematics (STEM) is a complex problem that continues to persist at the postsecondary level, particularly in computer science and engineering fields. This dissertation explored the pre-college and college level factors that influenced undergraduate women's persistence in STEM. This study also examined and compared the characteristics of undergraduate women who entered STEM fields and non-STEM fields in 2003-2004. The nationally representative Beginning Postsecondary Students Longitudinal Study (BPS:04/09) data set was used for analysis. BPS:04/09 study respondents were surveyed three times (NPSAS:04, BPS:04/06, BPS:04/09) over a six-year period, which enabled me to explore factors related to long-term persistence. Astin's Input-Environment-Output (I-E-O) model was used as the framework to examine student inputs and college environmental factors that predict female student persistence (output) in STEM. Chi-square tests revealed significant differences between undergraduate women who entered STEM and non-STEM fields in 2003-2004. Differences in student demographics, prior academic achievement, high school course-taking patterns, and student involvement in college such as participation in study groups and school clubs were found. Notably, inferential statistics showed that a significantly higher proportion of female minority students entered STEM fields than non-STEM fields. These findings challenge the myth that underrepresented female minorities are less inclined to enter STEM fields. Logistic regression analyses revealed thirteen significant predictors of persistence for undergraduate women in STEM. Findings showed that undergraduate women who were younger, more academically prepared, and academically and socially involved in college (e.g., lived on campus, interacted with faculty, participated in study groups, fine arts activities, and school sports) were more likely to persist in STEM

  19. Persistence drives gene clustering in bacterial genomes

    Directory of Open Access Journals (Sweden)

    Rocha Eduardo PC

    2008-01-01

    Full Text Available Abstract Background Gene clustering plays an important role in the organization of the bacterial chromosome and several mechanisms have been proposed to explain its extent. However, the controversies raised about the validity of each of these mechanisms remind us that the cause of this gene organization remains an open question. Models proposed to explain clustering did not take into account the function of the gene products nor the likely presence or absence of a given gene in a genome. However, genomes harbor two very different categories of genes: those genes present in a majority of organisms – persistent genes – and those present in very few organisms – rare genes. Results We show that two classes of genes are significantly clustered in bacterial genomes: the highly persistent and the rare genes. The clustering of rare genes is readily explained by the selfish operon theory. Yet, genes persistently present in bacterial genomes are also clustered and we try to understand why. We propose a model accounting specifically for such clustering, and show that indispensability in a genome with frequent gene deletion and insertion leads to the transient clustering of these genes. The model describes how clusters are created via the gene flux that continuously introduces new genes while deleting others. We then test if known selective processes, such as co-transcription, physical interaction or functional neighborhood, account for the stabilization of these clusters. Conclusion We show that the strong selective pressure acting on the function of persistent genes, in a permanent state of flux of genes in bacterial genomes, maintaining their size fairly constant, that drives persistent genes clustering. A further selective stabilization process might contribute to maintaining the clustering.

  20. Rotenone persistence model for montane streams

    Science.gov (United States)

    Brown, Peter J.; Zale, Alexander V.

    2012-01-01

    The efficient and effective use of rotenone is hindered by its unknown persistence in streams. Environmental conditions degrade rotenone, but current label instructions suggest fortifying the chemical along a stream based on linear distance or travel time rather than environmental conditions. Our objective was to develop models that use measurements of environmental conditions to predict rotenone persistence in streams. Detailed measurements of ultraviolet radiation, water temperature, dissolved oxygen, total dissolved solids (TDS), conductivity, pH, oxidation–reduction potential (ORP), substrate composition, amount of organic matter, channel slope, and travel time were made along stream segments located between rotenone treatment stations and cages containing bioassay fish in six streams. The amount of fine organic matter, biofilm, sand, gravel, cobble, rubble, small boulders, slope, pH, TDS, ORP, light reaching the stream, energy dissipated, discharge, and cumulative travel time were each significantly correlated with fish death. By using logistic regression, measurements of environmental conditions were paired with the responses of bioassay fish to develop a model that predicted the persistence of rotenone toxicity in streams. This model was validated with data from two additional stream treatment reaches. Rotenone persistence was predicted by a model that used travel time, rubble, and ORP. When this model predicts a probability of less than 0.95, those who apply rotenone can expect incomplete eradication and should plan on fortifying rotenone concentrations. The significance of travel time has been previously identified and is currently used to predict rotenone persistence. However, rubble substrate, which may be associated with the degradation of rotenone by adsorption and volatilization in turbulent environments, was not previously considered.

  1. Extending and implementing the Persistent ID pillars

    Science.gov (United States)

    Car, Nicholas; Golodoniuc, Pavel; Klump, Jens

    2017-04-01

    The recent double decade anniversary of scholarly persistent identifier use has triggered journal special editions such as "20 Years of Persistent Identifiers". For such a publication, it is apt to consider the longevity of some persistent identifier (PID) mechanisms (Digital Object Identifiers) and the partial disappearance of others (Life Sciences IDs). We have previously postulated a set of "PID Pillars" [1] which are design principles aimed at ensuring PIDs can survive technology and social change and thus persist for the long term that we have drawn from our observations of PIDs at work over many years. The principles: describe how to ensure identifiers' system and organisation independence; codify the delivery of essential PID system functions; mandate a separation of PID functions from data delivery mechanisms; and require generation of policies detailing how change is handled. In this presentation, first we extend on our previous work of introducing the pillars by refining their descriptions, giving specific suggestions for each and presenting some work that addresses them. Second, we propose a baseline data model for persistent identifiers that, if used, would assist the separation of PID metadata and PID system functioning. This would allow PID system function specifics to change over time (e.g. resolver services or even resolution protocols) and yet preserve the PIDs themselves. Third, we detail our existing PID system — the PID Service [2] — that partially implements the pillars and describe both its successes and shortcomings. Finally, we describe our planned next-generation system that will aim to use the baseline data model and fully implement the pillars.

  2. How to decode Unemployment Persistence: An econometric framework for identifying and comparing the sources of persistence

    DEFF Research Database (Denmark)

    Møller, Niels Framroze

    2016-01-01

    Most econometric analyses of persistence focus on the existence of non-stationary unemployment but not the origin of this. The present research contains a multivariate econometric framework for identifying and comparing different sources of unemployment persistence (e.g. hysteresis versus a slowly...... moving equilibrium rate). A small example, considering historical data (1988-2006) for the UK, demonstrates how the method can be applied in practice. Although this primarily serves as an illustration, the evidence clearly suggests that persistence was due to a slowly moving equilibrium (driven...

  3. Frequent occurrence of nonprimate hepacivirus infections in Thoroughbred breeding horses - A cross-sectional study for the occurrence of infections and potential risk factors.

    Science.gov (United States)

    Reichert, Claudia; Campe, Amely; Walter, Stephanie; Pfaender, Stephanie; Welsch, Kathrin; Ruddat, Inga; Sieme, Harald; Feige, Karsten; Steinmann, Eike; Cavalleri, Jessika M V

    2017-05-01

    Recently, several new hepaciviruses have been identified of which the nonprimate hepacivirus (NPHV) - the closest relative to hepatitis C virus (HCV) discovered to date - is highly prevalent in horses. However, potential risk factors for the transmission of NPHV among horses remain still unknown. Therefore, the objective of this study was to investigate the occurrence of NPHV infections in Thoroughbreds in northern and western Germany and to identify potential risk factors associated with NPHV infections. Using a cross-sectional study design, a total of 733 serum samples from Thoroughbred broodmares and stallions from northern and western Germany were analyzed for the presence of anti-NPHV nonstructural protein 3 (NS3) antibodies and NPHV RNA using the luciferase immunoprecipitation system (LIPS) and a quantitative real-time PCR, respectively. Information regarding signalment, stud farm, breeding history and international transportation history of each horse were collected and evaluated. A frequent occurrence of NPHV was found in the study population with 453 seropositive horses (61.8%) and 134 horses (18.3%) carrying NPHV RNA. Furthermore, statistical analysis revealed that the probability of being infected decreased for horses with a transportation history with increasing age by 20% each year. For horses that stayed in Germany no association between age and infection could be observed. In conclusion, the high occurrence of NPHV infections in breeding Thoroughbreds suggests circulating NPHV infections, endemic herds or persistent shedding in these animals and revealed the association of age and international transportation as risk factor for NPHV infections. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Identification of clinical and paraclinical findings predictive for headache occurrence during spontaneous subarachnoid hemorrhage.

    Science.gov (United States)

    Ljubisavljevic, Srdjan; Milosevic, Vuk; Stojanov, Aleksandar; Ljubisavljevic, Marina; Dunjic, Olivera; Zivkovic, Miroslava

    2017-07-01

    Headache is recognized as the main but unwarranted symptom of subarachnoid hemorrhage (SAH). There are no enough findings identified as predictive for headache occurrence in SAH. We evaluated the clinical and paraclinical factors predictive for headache occurrence in SAH. We retrospectively analyzed medical records of 431 consecutive non traumatic SAH patients (264 females and 167 males), ages from 19 to 91 years, presenting with headache (70.3%) and without headache (29.7%) during period of 11years. Among all tested parameters, as negative predictors for headache occurrence were recognized: patients' ages (OR 0.97 [95%CI: 0.96-0.99], p=0.025), persistence of coagulation abnormality (OR 0.23 [95%CI: 0.08-0.67], p=0.006), atrial fibrilation (OR 0.23 [95%CI: 0.09-0.59], p=0.002), chronic renal failure (OR 0.26 [95%CI: 0.09-0.76], p=0.014) and more diseases (OR 0.11 [95%CI: 0.04-0.32], p<0.0001), as higher clinical score (OR 0.94 [95%CI: 0.90-0.99], p=0.018) including positive neurological findings (OR 0.34 [95%CI: 0.21-0.55], p<0.001) and loss of consciousness (OR 0.22 [95%CI: 0.12-0.39], p<0.001) at the SAH onset, while the complaint of neck stiffness was identified as its positive predictor (OR 1.93 [95%CI: 1.19-3.10], p=0.007). Although diagnosis based solely on clinical presentation is not reliable and speculative, our findings could provide physicians with evidence to consider SAH not only in conditions of its headache occurrence but also in those with headache absence. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. The occurrence of emerging trace organic chemicals in wastewater effluents in Saudi Arabia

    KAUST Repository

    Alidina, Mazahirali

    2014-04-01

    Emerging trace organic chemicals (TOrCs) released into the environment via discharge of wastewater effluents have been detected in rivers and lakes worldwide, raising concerns due to their potential persistence, toxicity and bioaccumulation. This study provides the first reconnaissance of TOrC occurrence in wastewater effluents within Saudi Arabia. Four wastewater treatment plants (WWTPs 1-4) located in Western Saudi Arabia were sampled hourly over twelve-hour periods, for a total of six sampling events. All samples were analyzed for a wide range of TOrC encompassing pharmaceuticals, personal care products and household chemicals. Treatment and capacities of the plants varied from non-nitrifying to full biological nutrient removal providing a representative cross section of different types of plants operational within the country. A comparison of TOrC occurrence in effluents in Saudi Arabia with respective effluent qualities in the United States revealed similar levels for most TOrC. Overall, the occurrence of TOrC was higher at two of the plants. The higher TOrC concentrations at WWTP 1 are likely due to the non-nitrifying biological treatment process. The unique TOrC occurrence observed in the WWTP 3 effluent was unlike any other plant and was attributed to the influence of a large number of international visitors in its sewershed. The occurrence of TOrC in this plant was not expected to be representative of the occurrence elsewhere in the country. Bimodal diurnal variation expected for a range of TOrC was not observed, though some hourly variation in TOrC loading was noted for WWTP 3. Since water reclamation and reuse have received increasing interest in Saudi Arabia within the last few years, results from this study provide a good foundation in deciding whether advanced treatment is necessary to attenuate TOrC deemed to be of concern in effluents, or if natural treatment such as managed aquifer recharge provides sufficient protection to public health. © 2014

  6. Unusual occurrences in fast breeder test reactor

    International Nuclear Information System (INIS)

    Kapoor, R.P.; Srinivasan, G.; Ellappan, T.R.; Ramalingam, P.V.; Vasudevan, A.T.; Iyer, M.A.K.; Lee, S.M.; Bhoje, S.B.

    2000-01-01

    Fast Breeder Test Reactor (FBTR) is a 40 MWt/13.2 MWe sodium cooled mixed carbide fuelled reactor. Its main aim is to generate experience in the design, construction and operation of fast reactors including sodium systems and to serve as an irradiation facility for the development of fuel and structural materials for future fast reactors. It achieved first criticality in Oct 85 with Mark I core (70% PuC - 30% UC). Steam generator was put in service in Jan 93 and power was raised to 10.5 MWt in Dec 93. Turbine generator was synchronised to the grid in Jul 97. The indigenously developed mixed carbide fuel has achieved a burnup of 44,000 MW-d/t max at a linear heat rating of 320 W/cm max without any fuel clad failure. The commissioning and operation of sodium systems and components have been smooth and performance of major components, viz., sodium pumps, intermediate heat exchangers and once through sodium heated steam generators (SG) have been excellent. There have been three minor incidents of Na/NaK leaks during the past 14 years, which are described in the paper. There have been no incident of a tube leak in SG. However, three incidents of water leaks from water / steam headers have been detailed. The plant has encountered some unusual occurrences, which were critically analysed and remedial measures, in terms of system and procedural modifications, incorporated to prevent recurrence. This paper describes unusual occurrences of fuel handling incident of May 1987, main boiler feed pump seizure in Apr 1992, reactivity transients in Nov 1994 and Apr 1995, and malfunctioning of the core cover plate mechanism in Jul 1995. These incidents have resulted in long plant shutdowns. During the course of investigation, various theoretical and experimental studies were carried out for better understanding of the phenomena and several inspection techniques and tools were developed resulting in enriching the technology of sodium cooled reactors. FBTR has 36 neutronic and process

  7. Beachrock occurrence, characteristics, formation mechanisms and impacts

    Science.gov (United States)

    Vousdoukas, M. I.; Velegrakis, A. F.; Plomaritis, T. A.

    2007-11-01

    Beachrocks are hard coastal sedimentary formations consisting of various beach sediments, lithified through the precipitation of carbonate cements. The objectives of this contribution are to (a) collate and review information on the reported occurrences, characteristics and formation mechanisms of beachrocks and (b) consider their impacts on the coastal zone. The analysis of the available information has shown that (a) beachrock formation is a global and diachronic phenomenon and (b) the great majority of beachrocks are found in tropical/subtropical and low temperate latitude, microtidal coasts. The cementing agents of beachrocks are composed predominantly of the metastable carbonate phases High Magnesian Calcite (HMC) and Aragonite (Ar), appearing in a diverse crystalline morphology. It has been suggested that cement precipitation in the coastal environment is controlled by: (i) the physicochemical conditions; (ii) the presence of organic compounds and microbes; (iii) the magnitude and distribution of the wave energy along the coast; and (iv) the textural characteristics of the constituent sediments. Various theories have been proposed to explain beachrock formation itself, linking the phenomenon to either physicochemical or biological processes. These theories, however, do not seem to be of universal validity and acceptance, as each is able to explain only some of the reported occurrences. The presence of beachrocks appears to affect beach morphodynamics by: (i) 'locking' the beach profile; (ii) modifying the nearshore hydrodynamics; (iii) changing the porous character of the beach and, thus, its response to wave forcing; and (iv) differential bed erosion at the margins of the beachrock outcrops that can alter significantly the long- and, particularly, the cross-shore sediment transport. Therefore, although relict submerged beachrock outcrops may provide some coastal protection by reducing the wave energy impinging onto the coastline, modern beachrocks may

  8. Persistence of interest in science, technology, engineering and mathematics: An analysis of persisting and non-persisting students

    Science.gov (United States)

    White, Jeffry L.

    While there has been an increase in enrollment, interest in science, technology, engineering, and mathematics (STEM) has been declining on college campuses since 1967. Higher enrollment does not transfer to an increase in the number of minorities in the STEM fields. The majority-minority enrollment ratio is nearly 2:1 but the gap widens to 4:1 when it comes to graduation. In fact, underrepresented minorities (URM) earned only 12% of the STEM degrees awarded in 1998. When the higher attrition and lower graduation rates of URM are scrutinized, upwards of 60% changed majors or dropped out of STEM. Further investigation reveals the most frequently cited reasons for departure were loss of initial interest, developed a greater interest in another field, or were turned off by the STEM disciplines. A primarily exploratory study was conducted into the conditions necessary for academic interest in the STEM fields to persist. A model based on student engagement (Astin, 1977) and interest operations (Prenzel, 1988a) theories was used with a random sample of URM at universities participating in the Ohio Science and Engineering Alliance. Survey research was employed to investigate interest development and the effect of student retention programs and activities on such interest. The latter part of the study could not be fully examined when 95% reported not utilizing retention services. For the section on interest, an online survey using a 5-point Likert scale was validated using principal components analysis. A binominal logistic regression was used to predict membership in one of two possible groups: persisters and students at-risk for not persisting. The major conclusions are: (1) While 3 variables (feelings, learning and difficulty) were statistically significant only one, feelings was substantively significant. (2) Persistence increased 80.9% for each 1-unit increase in feelings and 9.9% for learning. (3) Persistence decreased 19.8% for each one-unit increase in difficulty

  9. Missing relationship of moyamoya and persistent primitive artery in Europeans. Another distinctive feature or artifact?

    Science.gov (United States)

    Wenz, Holger; Wenz, Ralf; Förster, Alex; Fontana, Johann; Kerl, Hans Ulrich; Groden, Christoph; Scharf, Johann

    2015-11-01

    Previous studies found higher incidence of persistent primitive arteries in Asian moyamoya (MM) patients than in the general population, which was thought to be a characteristic trait of the MM entity in general. We analyzed incidence of persistent primitive arteries and demographics of patients with European MM treated in one single center. First, we compared our large dataset to existing literature and second, we raised the question whether European MM demonstrates similar high prevalence of persistent primitive arteries as it was previously presented within Asian MM. All European MM on whom revascularization surgery was performed from 1999 to 2013 were included. Demographics and associated diseases were obtained by retrospective chart review. Two independent readers evaluated 122 MM angiograms to determine the occurrence of persistent primitive arteries as well as the Suzuki score. We identified 112 cases with MM disease, 10 with MM syndrome. Mean age at time of diagnosis was 38.2 (range 6-64 years); a peak incidence in early childhood was not observed. Ninety (73.8%) were women, associated systemic diseases were found in four patients. Seven cases (5.7%) presented with unilaterally affected vessels. The majority of patients (71; 58.2%) were graded Suzuki Score 3. One 14-year-old boy with moyamoya presented with a primitive trigeminal artery (0.89%). We did not find a bimodal age distribution, but only a second peak during adulthood. Unlike previous studies on Asian moyamoya patients, our collective does not exhibit a higher prevalence of persistent primitive arteries than the normal population.

  10. Emotional persistence in online chatting communities

    Science.gov (United States)

    Garas, Antonios; Garcia, David; Skowron, Marcin; Schweitzer, Frank

    2012-05-01

    How do users behave in online chatrooms, where they instantaneously read and write posts? We analyzed about 2.5 million posts covering various topics in Internet relay channels, and found that user activity patterns follow known power-law and stretched exponential distributions, indicating that online chat activity is not different from other forms of communication. Analysing the emotional expressions (positive, negative, neutral) of users, we revealed a remarkable persistence both for individual users and channels. I.e. despite their anonymity, users tend to follow social norms in repeated interactions in online chats, which results in a specific emotional ``tone'' of the channels. We provide an agent-based model of emotional interaction, which recovers qualitatively both the activity patterns in chatrooms and the emotional persistence of users and channels. While our assumptions about agent's emotional expressions are rooted in psychology, the model allows to test different hypothesis regarding their emotional impact in online communication.

  11. Persistent hyperlactacidaemia: about a clinical case.

    Science.gov (United States)

    Oliveira, Ana Rita Saraiva; Valente, Rosalina; Ramos, José; Ventura, Lurdes

    2013-05-22

    Lactate is the endogenous end product of the anaerobic glycolysis, whose production is favoured in situations of hypoperfusion or mitochondrial dysfunction. Leigh syndrome is a rare, progressive encephalomyopathy that represents a spectrum of mitochondrial genetic diseases phenotypically distinct, but with neuroradiological and pathological uniform presentation. We present the case of a 7-month-old infant, with a history of prematurity, psychomotor retardation and epilepsy, admitted to the paediatric intensive care unit (PICU) due to cardio-respiratory arrest because of respiratory infection. Hyperlactacidaemia was detected and was persistent. The study of redox potential was normal but MRI with spectroscopy identified bilateral and symmetrical lesions involving thalamic and basal ganglia, with small lactate peaks at T2 flair, findings that were suggestive of Leigh syndrome. Subsequent enzymatic study identified lack of pyruvate dehydrogenase. Persistent hyperlactacidaemia, in the appropriate clinical context, should lead to the screening of mitochondrial diseases.

  12. Persistent pulmonary hypertension of the newborn.

    Science.gov (United States)

    Nair, P M C; Bataclan, Maria Flordeliz A

    2004-06-01

    This article attempts to define a complicated, yet not rare disease of the neonate, which presents with extreme hypoxemia due to increased pulmonary vascular resistance, resulting in diversion of the pulmonary venous blood through persistent fetal channels, namely ductus arteriosus and foramen ovale. Pathophysiology, diagnostic approach and the various modalities of management are analyzed. Persistent pulmonary hypertension of the newborn is multi-factorial, which is reflected in the management as well. These babies are extremely labile to hypoxia and should be stabilized with minimum handling. One hundred percent oxygen and ventilation are the mainstay of treatment. The role of hyperventilation, alkalinization, various non-specific vasodilators such as tolazoline, magnesium sulphate, selective vasodilators such as inhaled nitric oxide, adenosine and the role of high frequency oscillatory ventilation and extra corporeal membrane oxygenation are discussed. With the newer modalities of management, the outlook has improved with mortality of less than 20% and fewer long-term deficits.

  13. Patients with persistent medically unexplained physical symptoms

    DEFF Research Database (Denmark)

    A, Aamland; Malterud, Kirsti; Werner, E.

    2014-01-01

    for all variables and split analysis on gender and age. RESULTS: The GPs registered 526 patients among their total of 17 688 consultations, giving a consultation prevalence of persistent MUPS of 3%. The mean age of patients was 46 years, and 399 (76%) were women. The most frequent group of symptoms...... was musculoskeletal problems, followed by asthenia/fatigue. There was no significant gender difference in symptom pattern. Almost half of the patients were currently working (45%), significantly more men. The major GP management strategy was supportive counseling. CONCLUSION: A consultation prevalence rate of 3......% implies that patients with persistent MUPS are common in general practice. Our study disclosed heterogeneity among the patients such as differences in employment status, which emphasizes the importance of personalized focus rather than unsubstantiated stereotyping of "MUPS patients" as a group....

  14. Persistent Identifiers for Dutch cultural heritage institutions

    Science.gov (United States)

    Ras, Marcel; Kruithof, Gijsbert

    2016-04-01

    Over the past years, more and more collections belonging to archives, libraries, media, museums, and knowledge institutes are being digitised and made available online. These are exciting times for ALM institutions. They are realising that, in the information society, their collections are goldmines. Unfortunately most heritage institutions in the Netherlands do not yet meet the basic preconditions for long-term availability of their collections. The digital objects often have no long lasting fixed reference yet. URL's and web addresses change. Some digital objects that were referenced in Europeana and other portals can no longer be found. References in scientific articles have a very short life span, which is damaging for scholarly research. In 2015, the Dutch Digital Heritage Network (NDE) has started a two-year work program to co-ordinate existing initiatives in order to improve the (long-term) accessibility of the Dutch digital heritage for a wide range of users, anytime, anyplace. The Digital Heritage Network is a partnership established on the initiative of the Ministry of Education, Culture and Science. The members of the NDE are large, national institutions that strive to professionally preserve and manage digital data, e.g. the National Library, The Netherlands Institute for Sound and Vision, the Netherlands Cultural Heritage Agency, the Royal Netherlands Academy of Arts and Sciences, the National Archive of the Netherlands and the DEN Foundation, and a growing number of associations and individuals both within and outside the heritage sector. By means of three work programmes the goals of the Network should be accomplished and improve the visibility, the usability and the sustainability of digital heritage. Each programme contains of a set of projects. Within the sustainability program a project on creating a model for persistent identifiers is taking place. The main goals of the project are (1) raise awareness among cultural heritage institutions on the

  15. Persistent Aerial Tracking system for UAVs

    KAUST Repository

    Mueller, Matthias

    2016-12-19

    In this paper, we propose a persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc.) integrating multiple UAVs with a stabilized RGB camera. A novel strategy is employed to successfully track objects over a long period, by ‘handing over the camera’ from one UAV to another. We evaluate several state-of-the-art trackers on the VIVID aerial video dataset and additional sequences that are specifically tailored to low altitude UAV target tracking. Based on the evaluation, we select the leading tracker and improve upon it by optimizing for both speed and performance, integrate the complete system into an off-the-shelf UAV, and obtain promising results showing the robustness of our solution in real-world aerial scenarios.

  16. Persistent Aerial Tracking system for UAVs

    KAUST Repository

    Mueller, Matthias; Sharma, Gopal; Smith, Neil; Ghanem, Bernard

    2016-01-01

    In this paper, we propose a persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc.) integrating multiple UAVs with a stabilized RGB camera. A novel strategy is employed to successfully track objects over a long period, by ‘handing over the camera’ from one UAV to another. We evaluate several state-of-the-art trackers on the VIVID aerial video dataset and additional sequences that are specifically tailored to low altitude UAV target tracking. Based on the evaluation, we select the leading tracker and improve upon it by optimizing for both speed and performance, integrate the complete system into an off-the-shelf UAV, and obtain promising results showing the robustness of our solution in real-world aerial scenarios.

  17. Geometry Helps to Compare Persistence Diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Kerber, Michael; Morozov, Dmitriy; Nigmetov, Arnur

    2015-11-16

    Exploiting geometric structure to improve the asymptotic complexity of discrete assignment problems is a well-studied subject. In contrast, the practical advantages of using geometry for such problems have not been explored. We implement geometric variants of the Hopcroft--Karp algorithm for bottleneck matching (based on previous work by Efrat el al.), and of the auction algorithm by Bertsekas for Wasserstein distance computation. Both implementations use k-d trees to replace a linear scan with a geometric proximity query. Our interest in this problem stems from the desire to compute distances between persistence diagrams, a problem that comes up frequently in topological data analysis. We show that our geometric matching algorithms lead to a substantial performance gain, both in running time and in memory consumption, over their purely combinatorial counterparts. Moreover, our implementation significantly outperforms the only other implementation available for comparing persistence diagrams.

  18. Imaging approach to persistent neonatal jaundice

    International Nuclear Information System (INIS)

    Kirks, D.; Coleman, R.E.; Filston, H.C.; Rosenberg, E.R.; Merten, D.F.

    1984-01-01

    Fifteen patients with persistent neonatal jaundice were evaluated by sonography and radionuclide scintigraphy. The sonographic features of both neonatal hepatitis and biliary atresia are nonspecific. Hepatobiliary scintigraphy after phenobarbital pretreatment in patients with neonatal hepatitis demonstrates normal hepatic extraction and delayed tracer excretion into the gastrointestinal tract. If there is neonatal hepatitis with severe hepatocellular damage, the hepatic extraction of tracer activity is decreased and excretion may be delayed or absent. Patients under 3 months of age with biliary atresia have normal hepatic extraction of tracer with no excretion into the gastrointestinal tract. Sonography in patients with a choledochal cyst shows a cystic mass in the porta hepatis with associated bile-duct dilatation. Hepatobiliary scintigraphy confirms that the choledochal cyst communicates with the biliary system. Initial sonography demonstrates hepatobiliary anatomy; subsequent phenobarbital-enhanced radionuclide scintigraphy determines hepatobiliary function. An expedient diagnostic approach is recommended for the evaluation of persistent neonatal jaundice

  19. Foreshock occurrence rates before large earthquakes worldwide

    Science.gov (United States)

    Reasenberg, P.A.

    1999-01-01

    Global rates of foreshock occurrence involving shallow M ??? 6 and M ??? 7 mainshocks and M ??? 5 foreshocks were measured, using earthquakes listed in the Harvard CMT catalog for the period 1978-1996. These rates are similar to rates ones measured in previous worldwide and regional studies when they are normalized for the ranges of magnitude difference they each span. The observed worldwide rates were compared to a generic model of earthquake clustering, which is based on patterns of small and moderate aftershocks in California, and were found to exceed the California model by a factor of approximately 2. Significant differences in foreshock rate were found among subsets of earthquakes defined by their focal mechanism and tectonic region, with the rate before thrust events higher and the rate before strike-slip events lower than the worldwide average. Among the thrust events a large majority, composed of events located in shallow subduction zones, registered a high foreshock rate, while a minority, located in continental thrust belts, measured a low rate. These differences may explain why previous surveys have revealed low foreshock rates among thrust events in California (especially southern California), while the worldwide observations suggest the opposite: California, lacking an active subduction zone in most of its territory, and including a region of mountain-building thrusts in the south, reflects the low rate apparently typical for continental thrusts, while the worldwide observations, dominated by shallow subduction zone events, are foreshock-rich.

  20. Widespread Natural Occurrence of Hydroxyurea in Animals.

    Science.gov (United States)

    Fraser, David I; Liu, Kyle T; Reid, Bryan J; Hawkins, Emily; Sevier, Andrew; Pyle, Michelle; Robinson, Jacob W; Ouellette, Pierre H R; Ballantyne, James S

    2015-01-01

    Here we report the widespread natural occurrence of a known antibiotic and antineoplastic compound, hydroxyurea in animals from many taxonomic groups. Hydroxyurea occurs in all the organisms we have examined including invertebrates (molluscs and crustaceans), fishes from several major groups, amphibians and mammals. The species with highest concentrations was an elasmobranch (sharks, skates and rays), the little skate Leucoraja erinacea with levels up to 250 μM, high enough to have antiviral, antimicrobial and antineoplastic effects based on in vitro studies. Embryos of L. erinacea showed increasing levels of hydroxyurea with development, indicating the capacity for hydroxyurea synthesis. Certain tissues of other organisms (e.g. skin of the frog (64 μM), intestine of lobster (138 μM) gills of the surf clam (100 μM)) had levels high enough to have antiviral effects based on in vitro studies. Hydroxyurea is widely used clinically in the treatment of certain human cancers, sickle cell anemia, psoriasis, myeloproliferative diseases, and has been investigated as a potential treatment of HIV infection and its presence at high levels in tissues of elasmobranchs and other organisms suggests a novel mechanism for fighting disease that may explain the disease resistance of some groups. In light of the known production of nitric oxide from exogenously applied hydroxyurea, endogenous hydoxyurea may play a hitherto unknown role in nitric oxide dynamics.

  1. Geology and occurrence of radon precursors

    International Nuclear Information System (INIS)

    Schmalz, R.F.

    1990-01-01

    The discovery that radioactive radon gas may occur as a significant indoor contaminant in houses and in the workplace has had far-reaching consequences in public health, real estate marketing, the construction industry, health and liability insurance underwriting, and in legislation at the federal and state levels. Many factors are known to affect radon level inside a building - its location, construction, ventilation, and substructure; the climate of the region in which it is located and the life styles of it occupants, for example. Despite the importance of assessing the hazard radon contamination may represent, the economic cost and the time required to screen hundreds of millions of individual buildings make such an effort impracticable. The effectiveness of large-scale regional screening to evaluate radon potential depends on an understanding of the chemical and physical properties of the gas, and of the geological and geochemical factors which control the distribution of its radioactive progenitors, radium, uranium and thorium. It is the purpose of this paper to review and summarize our present knowledge of these large-scale controls on radon occurrence

  2. Simultaneous Occurrence of Dens Invaginatus and Fusion

    Directory of Open Access Journals (Sweden)

    Amit Mhapuskar

    2013-01-01

    Full Text Available Although Dens invaginatus and fusion are well-known and well established dental anomalies, they are rarely seen in supernumerary teeth. In this article, simultaneous occurrence of Dens invaginatus and fusion between maxillary lateral incisor and a supernumerary tooth is described. Dens invaginatus is clinically significant due to the possibility of the pulpal involvement; pulpitis, necrotic pulps and chronic periapical lesions are often associated with this anomaly without clinical symptoms. Fusion has a negative impact on the aesthetics, especially when it occurs in maxillary anterior teeth. It is difficult to clinically make differential diagnosis between fused teeth and geminated teeth, especially when these anomalies take place together with hypodontia or supernumerary tooth. It has been found that sequel of such teeth may result in delayed eruption, ectopic eruption or even impaction of permanent teeth; hence proper diagnosis by clinical and radiographic methods and intervention at appropriate time is of paramount importance. The accurate knowledge of variations in morphology of tooth and pulp cavity greatly assists the dentist in planning successful treatment options.

  3. Widespread Natural Occurrence of Hydroxyurea in Animals.

    Directory of Open Access Journals (Sweden)

    David I Fraser

    Full Text Available Here we report the widespread natural occurrence of a known antibiotic and antineoplastic compound, hydroxyurea in animals from many taxonomic groups. Hydroxyurea occurs in all the organisms we have examined including invertebrates (molluscs and crustaceans, fishes from several major groups, amphibians and mammals. The species with highest concentrations was an elasmobranch (sharks, skates and rays, the little skate Leucoraja erinacea with levels up to 250 μM, high enough to have antiviral, antimicrobial and antineoplastic effects based on in vitro studies. Embryos of L. erinacea showed increasing levels of hydroxyurea with development, indicating the capacity for hydroxyurea synthesis. Certain tissues of other organisms (e.g. skin of the frog (64 μM, intestine of lobster (138 μM gills of the surf clam (100 μM had levels high enough to have antiviral effects based on in vitro studies. Hydroxyurea is widely used clinically in the treatment of certain human cancers, sickle cell anemia, psoriasis, myeloproliferative diseases, and has been investigated as a potential treatment of HIV infection and its presence at high levels in tissues of elasmobranchs and other organisms suggests a novel mechanism for fighting disease that may explain the disease resistance of some groups. In light of the known production of nitric oxide from exogenously applied hydroxyurea, endogenous hydoxyurea may play a hitherto unknown role in nitric oxide dynamics.

  4. Persistent hepatitis virus infection and immune homeostasis

    OpenAIRE

    ZHOU Yun

    2014-01-01

    Homeostasis between the host and viruses is naturally maintained. On the one hand, the immune system activates the immune response to kill or eliminate viruses; on the other hand, the immune system controls the immune response to maintain immune homeostasis. The cause of persistent infections with hepatitis viruses such as HBV and HCV is that viral molecules damage the immune system of the host and their variants escape immune clearance. Long-term coexistence of the host and viruses is the pr...

  5. The persistence of marketing effects on sales

    OpenAIRE

    Dekimpe, Marnik; Hanssens, DM

    1993-01-01

    Are marketing efforts able to affect long-term trends in sales or other performance measures? Answering this question is essential for the creation of marketing strategies that deliver a sustainable competitive advantage. This paper introduces persistence modeling to derive long-term marketing effectiveness from time-series observations on sales and marketing expenditures. First, we use unit-root tests to determine whether sales are stable or evolving (trending) over time. If they are evolvin...

  6. Mobility-induced persistent chimera states

    Science.gov (United States)

    Petrungaro, Gabriela; Uriu, Koichiro; Morelli, Luis G.

    2017-12-01

    We study the dynamics of mobile, locally coupled identical oscillators in the presence of coupling delays. We find different kinds of chimera states in which coherent in-phase and antiphase domains coexist with incoherent domains. These chimera states are dynamic and can persist for long times for intermediate mobility values. We discuss the mechanisms leading to the formation of these chimera states in different mobility regimes. This finding could be relevant for natural and technological systems composed of mobile communicating agents.

  7. Understanding and Responding to Persistently High Unemployment

    Science.gov (United States)

    2012-02-01

    Persistent Effects of Job Displacement: The Importance of Multiple Job Losses,” Journal of Labor Economics , vol. 15, no. 1, part 1 (January 1997), pp...Capital: Evidence from Displaced Workers,” Journal of Labor Economics , vol. 13, no. 4 (October 1995), pp. 653–677.one-third had trouble meeting...Effects of Worker Displacement,” Journal of Labor Economics , vol. 26, no. 3 (July 2008), pp. 455–483. completed its most recent economic forecast), that

  8. Actinomyces associated with persistent vaginal granulation tissue.

    OpenAIRE

    Wai, Clifford Y; Nihira, Mikio A; Drewes, Peter G; Chang, Joe S; Siddiqui, Momin T; Hemsell, David L

    2005-01-01

    BACKGROUND: We report a case of symptomatic actinomycosis associated with vaginal suture erosion and granulation tissue refractory to conservative management, in an outpatient setting. CASE: Three months after total vaginal hysterectomy and uterosacral ligament vaginal vault suspension, a woman complained of painless, intermittent vaginal discharge and spotting. Despite cauterization of granulation tissue, vaginal spotting persisted for another month. On re-examination, braided polyester sutu...

  9. Persistent postsurgical pain: risk factors and prevention

    DEFF Research Database (Denmark)

    Kehlet, Henrik; Jensen, Troels Staehelin; Woolf, Clifford J.

    2006-01-01

    therapy for postoperative pain should be investigated, since the intensity of acute postoperative pain correlates with the risk of developing a persistent pain state. Finally, the role of genetic factors should be studied, since only a proportion of patients with intraoperative nerve damage develop...... chronic pain. Based on information about the molecular mechanisms that affect changes to the peripheral and central nervous system in neuropathic pain, several opportunities exist for multimodal pharmacological intervention. Here, we outline strategies for identification of patients at risk...

  10. Information persistence using XML database technology

    Science.gov (United States)

    Clark, Thomas A.; Lipa, Brian E. G.; Macera, Anthony R.; Staskevich, Gennady R.

    2005-05-01

    The Joint Battlespace Infosphere (JBI) Information Management (IM) services provide information exchange and persistence capabilities that support tailored, dynamic, and timely access to required information, enabling near real-time planning, control, and execution for DoD decision making. JBI IM services will be built on a substrate of network centric core enterprise services and when transitioned, will establish an interoperable information space that aggregates, integrates, fuses, and intelligently disseminates relevant information to support effective warfighter business processes. This virtual information space provides individual users with information tailored to their specific functional responsibilities and provides a highly tailored repository of, or access to, information that is designed to support a specific Community of Interest (COI), geographic area or mission. Critical to effective operation of JBI IM services is the implementation of repositories, where data, represented as information, is represented and persisted for quick and easy retrieval. This paper will address information representation, persistence and retrieval using existing database technologies to manage structured data in Extensible Markup Language (XML) format as well as unstructured data in an IM services-oriented environment. Three basic categories of database technologies will be compared and contrasted: Relational, XML-Enabled, and Native XML. These technologies have diverse properties such as maturity, performance, query language specifications, indexing, and retrieval methods. We will describe our application of these evolving technologies within the context of a JBI Reference Implementation (RI) by providing some hopefully insightful anecdotes and lessons learned along the way. This paper will also outline future directions, promising technologies and emerging COTS products that can offer more powerful information management representations, better persistence mechanisms and

  11. Anomaly equations and the persistent mass condition

    International Nuclear Information System (INIS)

    Cohen, E.; Frishman, Y.

    1982-01-01

    Vector SU(Nsub(c)) gauge theories with nsub(f) flavors in the fundamental representation are considered. We prove that if the persistent mass condition is assumed, the two anomaly equations are identical and flavor independent for nsub(f) >= 3. Integer solutions exist only for nsub(f) = 2. The necessity of a separate discussion for 2 <= nsub(f) <= Nsub(c) is explained. (orig.)

  12. [Persistent duodenal septum in an adult].

    Science.gov (United States)

    Helwing, E; Echtermeyer, V; Otten, G

    1977-02-01

    A case of duodenal obstruction by a congenital duodenal web in a 34-year-old woman is presented. A mucosal diaphragm obstructed the duodenum. It showed an excentric opening of 0.8 cm diameter, but the dilated diaphragm caused a total stop during the last months. Despite a typical history, exact X-ray, and endoscopic examination, the correct preoperative diagnosis was not found, because nobody thought it possible, that a mucosal diapharm of the duodenum could persist for 34 years.

  13. Endorectal magnetic resonance imaging in persistent hemospermia

    International Nuclear Information System (INIS)

    Prando, Adilson

    2008-01-01

    Objective: To present the spectrum of abnormalities found at endorectal magnetic resonance imaging (E-MRI), in patients with persistent hemospermia. Materials and methods: A review of E-MRI findings observed in 86 patients with persistent hemospermia was performed and results compared with those reported in the literature. Follow-up was possible in 37 of 86 (43%) patients with hemospermia. Results: E-MRI showed abnormal findings in 52 of 86 (60%) patients with hemospermia. These findings were: a) hemorrhagic seminal vesicle and ejaculatory duct, isolated (n = 11 or 21%) or associated with complicated midline prostatic cyst (n = 10 or 19.0%); b) hemorrhagic chronic seminal vesiculitis, isolated (n = 14 or 27%) or associated with calculi within dilated ejaculatory ducts (n = 2 or 4 %); c) hemorrhagic seminal vesicle associated with calculi within dilated ejaculatory duct (n = 4 or 7.7%) or within seminal vesicle (n = 4 or 7.7%); d) non-complicated midline prostatic cyst (n = 6 or 11.5%); and e) prostate cancer (n = 1 or 2%). Successful treatment was more frequent in patients with chronic inflammatory and/or obstructive abnormalities. Conclusion: E-MRI should be considered the modality of choice, for the evaluation of patients with persistent hemospermia. (author)

  14. Endorectal magnetic resonance imaging in persistent hemospermia

    Energy Technology Data Exchange (ETDEWEB)

    Prando, Adilson [Vera Cruz Hospital, Campinas, SP (Brazil). Dept. of Radiology and Diagnostic Imaging

    2008-03-15

    Objective: To present the spectrum of abnormalities found at endorectal magnetic resonance imaging (E-MRI), in patients with persistent hemospermia. Materials and methods: A review of E-MRI findings observed in 86 patients with persistent hemospermia was performed and results compared with those reported in the literature. Follow-up was possible in 37 of 86 (43%) patients with hemospermia. Results: E-MRI showed abnormal findings in 52 of 86 (60%) patients with hemospermia. These findings were: a) hemorrhagic seminal vesicle and ejaculatory duct, isolated (n = 11 or 21%) or associated with complicated midline prostatic cyst (n = 10 or 19.0%); b) hemorrhagic chronic seminal vesiculitis, isolated (n = 14 or 27%) or associated with calculi within dilated ejaculatory ducts (n = 2 or 4 %); c) hemorrhagic seminal vesicle associated with calculi within dilated ejaculatory duct (n = 4 or 7.7%) or within seminal vesicle (n = 4 or 7.7%); d) non-complicated midline prostatic cyst (n = 6 or 11.5%); and e) prostate cancer (n = 1 or 2%). Successful treatment was more frequent in patients with chronic inflammatory and/or obstructive abnormalities. Conclusion: E-MRI should be considered the modality of choice, for the evaluation of patients with persistent hemospermia. (author)

  15. Lactase Non-persistence and Lactose Intolerance.

    Science.gov (United States)

    Bayless, Theodore M; Brown, Elizabeth; Paige, David M

    2017-05-01

    To evaluate the clinical and nutritional significance of genetically determined lactase non-persistence and potential lactose and milk intolerance in 65-70% of the world's adult population. Milk consumption is decreasing in the USA and is the lowest in countries with a high prevalence of lactase non-persistence. The dairy industry and Minnesota investigators have made efforts to minimize the influence of lactose intolerance on milk consumption. Some lactose intolerant individuals, without co-existent irritable bowel syndrome, are able to consume a glass of milk with a meal with no or minor symptoms. The high frequency of lactase persistence in offspring of Northern European countries and in some nomadic African tribes is due to mutations in the promoter of the lactase gene in association with survival advantage of milk drinking. Educational and commercial efforts to improve calcium and Vitamin D intake have focused on urging consumption of tolerable amounts of milk with a meal, use of lowered lactose-content foods including hard cheeses, yogurt, and lactose-hydrolyzed milk products.

  16. Persistent physical symptoms as perceptual dysregulation

    DEFF Research Database (Denmark)

    Henningsen, Peter; Gündel, Harald; Kop, Willem J

    2018-01-01

    OBJECTIVE: The mechanisms underlying the perception and experience of persistent physical symptoms are not well understood, and in the models, the specific relevance of peripheral input versus central processing, or of neurobiological versus psychosocial factors in general, is not clear.In this a......OBJECTIVE: The mechanisms underlying the perception and experience of persistent physical symptoms are not well understood, and in the models, the specific relevance of peripheral input versus central processing, or of neurobiological versus psychosocial factors in general, is not clear.......In this article, we propose a model for this clinical phenomenon that is designed to be coherent with an underlying, relatively new model of the normal brain functions involved in the experience of bodily signals. METHODS: Based on a review of recent literature we describe central elements of this model and its...... of predictions and sensory input. Two possibilities exist: adaptation of the generative model underlying the predictions or alteration of the sensory input via autonomic nervous activation (in the case of interoception). Following this model, persistent physical symptoms can be described as "failures...

  17. Persistent producer-scrounger relationships in bats.

    Science.gov (United States)

    Harten, Lee; Matalon, Yasmin; Galli, Naama; Navon, Hagit; Dor, Roi; Yovel, Yossi

    2018-02-01

    Social foraging theory suggests that group-living animals gain from persistent social bonds, which lead to increased tolerance in competitive foraging and information sharing. Bats are among the most social mammals, often living in colonies of tens to thousands of individuals for dozens of years, yet little is known about their social foraging dynamics. We observed three captive bat colonies for over a year, quantifying >13,000 social foraging interactions. We found that individuals consistently used one of two foraging strategies, either producing (collecting) food themselves or scrounging it directly from the mouth of other individuals. Individual foraging types were consistent over at least 16 months except during the lactation period when females shifted toward producing. Scroungers intentionally selected whom to interact with when socially foraging, thus generating persistent nonrandom social relationships with two to three specific producers. These persistent producer-scrounger relationships seem to reduce aggression over time. Finally, scrounging was highly correlated with vigilance, and we hypothesize that vigilant-prone individuals turn to scrounging in the wild to mitigate the risk of landing on a potentially unsafe fruit tree. We find the bat colony to be a rich and dynamic social system, which can serve as a model to study the role that social foraging plays in the evolution of mammalian sociality. Our results highlight the importance of considering individual tendencies when exploring social behavior patterns of group-living animals. These tendencies further emphasize the necessity of studying social networks over time.

  18. Overview of persistent pain in older adults.

    Science.gov (United States)

    Molton, Ivan R; Terrill, Alexandra L

    2014-01-01

    With the shifting age demographics of the U.S. population, more psychologists will be asked to provide clinical services to older adults. Given the high prevalence of persistent pain in aging, in many cases this will mean providing empirically supported interventions for pain and the interference it creates. The purpose of this review is to provide a broad overview of the scope and impact of persistent pain in older people and to discuss mechanisms by which persistent geriatric pain can lead to suffering and disability. We consider the unique context of pain in older adulthood and review differences between older and younger people in terms of pain perception, the social network, beliefs about pain, pain-related coping, and adherence to pain medication. Finally, we discuss special issues affecting pain management in older adults, including dementia, polypharmacy, and barriers to accessing adequate pain care. This review also highlights a need for greater provider training in pain management to meet the needs of a changing U.S. population. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  19. Sputum Neutrophilia in Severe Persistent Asthmatics

    International Nuclear Information System (INIS)

    Naseem, A.; Zaidi, S. B. H.; Liaqat, J.; Iftikhar, R.

    2014-01-01

    Objective: To determine the frequency of sputum neutrophilia in patients with severe persistent bronchial asthma. Study Design: A cross-sectional study. Place and Duration of Study: Department of Medicine, Military Hospital, Rawalpindi, from November 2009 to November 2010. Methodology: Cases of severe persistent bronchial asthma, aged between 12 and 40 years, were included. Sputum samples were collected by induction with hypertonic saline (4.5%). All samples were centrifuged and differential neutrophil count was calculated. Data was analyzed using SPSS 11. Results: Out of 195 patients, there were 129 (66.2%) males and 66 (33.8%) females. The mean age was 27.01 A +- 6.92 years. Mean sputum neutrophilic count was 126.47 A +- 16.52 x 106/ml and the mean neutrophilic percentage was 63.187 A +- 8.3363. Sputum neutrophilia was present in 84 patients (43.1%), out of whom, 56 were males and 28 females. In patients with sputum neutrophilia, mean neutrophilic count was 142.40 A +- 8.49 x 106/ml and the mean neutrophilic percentage was 71.2024 A +- 4.2441%. Conclusion: Sputum neutrophilia is a frequent finding in cases with severe persistent bronchial asthma. Presence of sputum neutrophilia in such cases can lessen the inappropriate use of corticosteroids with their associated long-term side effects. (author)

  20. University Experiences and Women Engineering Student Persistence

    Science.gov (United States)

    Ayers, LoAnn Debra Gienger

    Riverside University (a pseudonym), like many universities, has not significantly increased the number of women who graduate with bachelor's degrees in engineering. The purpose of the study is to understand how the university experiences of women students influence the decision to persist in an undergraduate engineering degree and to understand the role of self-perception in how the students perceive experiences as supporting or hindering their persistence in the major. Archival data, documents and artifacts, observations, individual interviews, and a focus group with women engineering students provide insights into students' perceived barriers and supports of student success. Analysis of the data results in two major themes. First, students' self-confidence and self-efficacy influence how women assimilate university experiences as either supportive or diminishing of academic success. Second, university policies and practices shape the campus environment within which student experiences are formed and influence a student's level of institutional, academic, and social integration. The results of the study indicate opportunities for university leadership to enhance strategies that positively shape students' institutional, academic and social integration as precursors toward increasing the number of women students who successfully complete undergraduate engineering degrees at Riverside University. Future research is indicated to better understand how gender and gender identity intersects with other demographic factors, such as socio-economic status, immigration status, and life stage (e.g., traditional versus non-traditional students), to support or deter the persistence of engineering students to degree completion.

  1. Reoperation for persistent or recurrent secondary hyperparathyroidism.

    Science.gov (United States)

    Abruzzo, Alida; Gioviale, Maria Concetta; Damiano, Giuseppe; Palumbo, Vincenzo Davide; Buscemi, Salvatore; Lo Monte, Giulia; Gulotta, Leonardo; Buscemi, Giuseppe; Lo Monte, Attilio Ignazio

    2017-10-23

    Secondary hyperparathyroidism is a common acquired disorder seen in chronic renal failure. Its pathophysiology is mainly due to hyperphosphatemia and vitamin D deficiency and resistance. When medical treatment fails, subtotal and total parathyroidectomy with autotransplantation are the standard procedures, although both are associated with high recurrence rates. 4 patients experienced persistence and 9 relapse. The first 4 were subjected to reoperation after 6 months for the persistence of symptoms due to the finding of a supernumerary adenomatous gland while the remaining patients at the reoperation showed in 5 cases 2 more glands in over thymic position, and 4 an hyperplasia of the residual glandular tissue. A classic cervicotomy was sufficient to remove the residual parathyroid in patients with persistent hyperparathyroidism. For cases of recurrent hyperparathyroidism it was enough a medial approach and sometimes lateral for the complete excision of the hyperplastic tissue. The advent of the intraoperative technique of parathyroid hormone dosage allowed a better performance of the surgical technique for the last 3 patients undergoing reoperation. After reoperation all patients had immediate regression of clinical symptoms with normalization of serum calcium and PTH levels. On the basis of these considerations, diagnostic imaging has a not negligible role because during the first intervention helps to have an idea of the possible location of the glands and thus to avoid the risk of recurrence and relapse due to ectopic or supernumerary tissue.

  2. Report to Congress on abnormal occurrences, April--June 1989

    International Nuclear Information System (INIS)

    1989-10-01

    The Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. For this reporting period, there was one abnormal occurrence at nuclear power plants licensed to operate involving significant deficiencies in management controls at Slurry Nuclear Power Station. There was one abnormal occurrence under other NRC-issued licenses; the event involved a medical therapy misadministration. One other abnormal occurrence, involving industrial radiography overexposures, was reported by an Agreement State (Texas). 40 refs

  3. Multivariate Hawkes process models of the occurrence of regulatory elements

    DEFF Research Database (Denmark)

    Carstensen, L; Sandelin, A; Winther, Ole

    2010-01-01

    distribution of the occurrences of these TREs along the genome. RESULTS: We present a model of TRE occurrences known as the Hawkes process. We illustrate the use of this model by analyzing two different publically available data sets. We are able to model, in detail, how the occurrence of one TRE is affected....... For each of the two data sets we provide two results: first, a qualitative description of the dependencies among the occurrences of the TREs, and second, quantitative results on the favored or avoided distances between the different TREs. CONCLUSIONS: The Hawkes process is a novel way of modeling the joint...

  4. The occurrence and frequency of genomic mutations that mediate ...

    African Journals Online (AJOL)

    The occurrence and frequency of genomic mutations that mediate Isoniazid and Rifampicin resistance in Mycobacterium tuberculosis isolates from untreated pulmonary Tuberculosis cases in urban Blantyre, Malawi.

  5. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Science.gov (United States)

    2010-04-01

    ...: Accidental Radiation Occurrence Reports (HFZ-240), Office of Communication, Education, and Radiation Programs, 9200 Corporate Blvd., Rockville, MD 20850, and the reports and their envelopes shall be distinctly...

  6. Adolescents' experience of complex persistent pain.

    Science.gov (United States)

    Sørensen, Kari; Christiansen, Bjørg

    2017-04-01

    Persistent (chronic) pain is a common phenomenon in adolescents. When young people are referred to a pain clinic, they usually have amplified pain signals, with pain syndromes of unconfirmed ethology, such as fibromyalgia and complex regional pain syndrome (CRPS). Pain is complex and seems to be related to a combination of illness, injury, psychological distress, and environmental factors. These young people are found to have higher levels of distress, anxiety, sleep disturbance, and lower mood than their peers and may be in danger of entering adulthood with mental and physical problems. In order to understand the complexity of persistent pain in adolescents, there seems to be a need for further qualitative research into their lived experiences. The aim of this study was to explore adolescents' experiences of complex persistent pain and its impact on everyday life. The study has an exploratory design with individual in-depth interviews with six youths aged 12-19, recruited from a pain clinic at a main referral hospital in Norway. A narrative approach allowed the informants to give voice to their experiences concerning complex persistent pain. A hermeneutic analysis was used, where the research question was the basis for a reflective interpretation. Three main themes were identified: (1) a life with pain and unpleasant bodily expressions; (2) an altered emotional wellbeing; and (3) the struggle to keep up with everyday life. The pain was experienced as extremely strong, emerging from a minor injury or without any obvious causation, and not always being recognised by healthcare providers. The pain intensity increased as the suffering got worse, and the sensation was hard to describe with words. Parts of their body could change in appearance, and some described having pain-attacks or fainting. The feeling of anxiety was strongly connected to the pain. Despair and uncertainty contributed to physical disability, major sleep problems, school absence, and withdrawal from

  7. Trustworthy persistent identifier systems of the future

    Science.gov (United States)

    Golodoniuc, Pavel; Klump, Jens; Car, Nicholas

    2016-04-01

    Over the last two decades, persistent identifier (PID) systems have seen some significant changes in their governance policies, system capabilities, and technology. The development of most systems was driven by two main application areas, namely archives and libraries. Guidelines and criteria for trustworthy PID systems have been clearly devised (Bütikofer, 2009) and many PID system implementations for the identification of static digital objects have been built (e.g., PURL). However systems delivering persistent identifiers for dynamic datasets are not yet mature. There has been a rapid proliferation of different PID systems caused by the specific technical or organisational requirements of various communities that could not be met by existing systems such as DOI, ISBN, and EAN. Many of these different systems were limited by their inability to provide native means of persistent identifier resolution. This has prompted a decoupling of PID-associated data from the resolution service and this is where the Handle system has played a significant role. The Handle allowed to build a distributed system of independently managed resolver services. A trustworthy PID system must be designed to outlive the objects it provides persistent identifiers for, which may cease to exist or otherwise be deprecated, and the technology used to implement it, which will certainly need to change with time. We propose that such a system should rest on four pillars of agreements - (i) definitions, (ii) policies, (iii) services, and (iv) data services, to ensure longevity. While we believe all four pillars are equally important, we intentionally leave regulating aspects of issuing of identifiers and their registration out of the scope of this paper and focus on the agreements that have to be established between PID resolver services and the data sources indicated by the persistent identifiers. We propose an approach to development of PID systems that combines the use of (a) the Handle system

  8. Frequency and Cause of Persistent Symptoms in Celiac Disease Patients on a Long-term Gluten-free Diet.

    Science.gov (United States)

    Stasi, Elisa; Marafini, Irene; Caruso, Roberta; Soderino, Federica; Angelucci, Erika; Del Vecchio Blanco, Giovanna; Paoluzi, Omero A; Calabrese, Emma; Sedda, Silvia; Zorzi, Francesca; Pallone, Francesco; Monteleone, Giovanni

    2016-03-01

    To estimate the frequency and cause of nonresponsive celiac disease (CD). Treatment of CD is based on life-long adherence to a gluten-free diet (GFD). Some celiac patients experience persistence of symptoms despite a GFD. This condition is defined as nonresponsive CD. Celiac patients on a GFD for at least 12 months underwent diet compliance assessment, laboratory tests, breath tests, endoscopic, and histologic evaluations according to the symptoms/signs reported. Seventy of 321 (21.8%) patients had persistent or recurrent symptoms/signs. The cause of symptom persistence was evaluated in 56 of 70 patients. Thirteen of 56 (23%) patients were antiendomysial antibody positive. Among the patients with negative serology, 1 had fibromyalgia, and 3 had evidence that disproved the diagnosis of CD. The remaining 39 patients with negative serology underwent duodenal biopsy sampling, which evidenced histologic alterations in 24 patients. Among the 15 patients with normal histology 3 were lactose intolerant, 9 had irritable bowel syndrome, 2 had gastroesophageal reflux disease, and in 1 patient a cause for the persistent symptom was not identified. In patients with confirmed diagnosis of CD, exposure to dietary gluten was the main cause of persistence of symptoms/signs, and consistently after dietary modification, symptoms resolved in 63% of the patients at later time points during follow-up. Nonresponsive CD occurs in nearly one fifth of celiac patients on GFD and its occurrence suggests further investigations to optimize the management of celiac patients.

  9. Interplanetary Parameters Leading to Relativistic Electron Enhancement and Persistent Depletion Events at Geosynchronous Orbit and Potential for Prediction

    Science.gov (United States)

    Pinto, Victor A.; Kim, Hee-Jeong; Lyons, Larry R.; Bortnik, Jacob

    2018-02-01

    We have identified 61 relativistic electron enhancement events and 21 relativistic electron persistent depletion events during 1996 to 2006 from the Geostationary Operational Environmental Satellite (GOES) 8 and 10 using data from the Energetic Particle Sensor (EPS) >2 MeV fluxes. We then performed a superposed epoch time analysis of the events to find the characteristic solar wind parameters that determine the occurrence of such events, using the OMNI database. We found that there are clear differences between the enhancement events and the persistent depletion events, and we used these to establish a set of threshold values in solar wind speed, proton density and interplanetary magnetic field (IMF) Bz that can potentially be useful to predict sudden increases in flux. Persistent depletion events are characterized by a low solar wind speed, a sudden increase in proton density that remains elevated for a few days, and a northward turning of IMF Bz shortly after the depletion starts. We have also found that all relativistic electron enhancement or persistent depletion events occur when some geomagnetic disturbance is present, either a coronal mass ejection or a corotational interaction region; however, the storm index, SYM-H, does not show a strong connection with relativistic electron enhancement events or persistent depletion events. We have tested a simple threshold method for predictability of relativistic electron enhancement events using data from GOES 11 for the years 2007-2010 and found that around 90% of large increases in electron fluxes can be identified with this method.

  10. Postpartum consultation: Occurrence, requirements and expectations

    Directory of Open Access Journals (Sweden)

    Carlgren Ingrid

    2008-07-01

    Full Text Available Abstract Background As a matter of routine, midwives in Sweden have spoken with women about their experiences of labour in a so-called 'postpartum consultation'. However, the possibility of offering women this kind of consultation today is reduced due to shortage of both time and resources. The aim of this study was to explore the occurrence, women's requirements of, and experiences of a postpartum consultation, and to identify expectations from women who wanted but did not have a consultation with the midwife assisting during labour. Methods All Swedish speaking women who gave birth to a live born child at a University Hospital in western Sweden were consecutively included for a phone interview over a three-week period. An additional phone interview was conducted with the women who did not have a postpartum consultation, but who wanted to talk with the midwife assisting during labour. Data from the interviews were analysed using qualitative content analysis. Results Of the 150 interviewed women, 56% (n = 84 had a postpartum consultation of which 61.9% (n = 52 had this with the midwife assisting during labour. Twenty of the 28 women who did not have a consultation with anyone still desired to talk with the midwife assisting during labour. Of these, 19 were interviewed. The content the women wanted to talk about was summarized in four categories: to understand the course of events during labour; to put into words, feelings about undignified management; to describe own behaviour and feelings, and to describe own fear. Conclusion The survey shows that the frequency of postpartum consultation is decreasing, that the majority of women who give birth today still require it, but only about half of them receive it. It is crucial to develop a plan for these consultations that meets both the women's needs and the organization within current maternity care.

  11. Occurrence of Legionella in UK household showers.

    Science.gov (United States)

    Collins, Samuel; Stevenson, David; Bennett, Allan; Walker, Jimmy

    2017-04-01

    Household water systems have been proposed as a source of sporadic, community acquired Legionnaires' disease. Showers represent a frequently used aerosol generating device in the domestic setting yet little is known about the occurrence of Legionella spp. in these systems. This study has investigated the prevalence of Legionella spp. by culture and qPCR in UK household showers. Ninety nine showers from 82 separate properties in the South of England were sampled. Clinically relevant Legionella spp. were isolated by culture in 8% of shower water samples representing 6% of households. Legionella pneumophila sg1 ST59 was isolated from two showers in one property and air sampling demonstrated its presence in the aerosol state. A further 31% of showers were positive by Legionella spp. qPCR. By multi-variable binomial regression modelling Legionella spp. qPCR positivity was associated with the age of the property (p=0.02), the age of the shower (p=0.01) and the frequency of use (p=0.09). The concentration of Legionella spp. detected by qPCR was shown to decrease with increased frequency of use (p=0.04) and more frequent showerhead cleaning (p=0.05). There was no association between Legionella spp. qPCR positivity and the cold water supply or the showerhead material (p=0.65 and p=0.71, respectively). Household showers may be important reservoirs of clinically significant Legionella and should be considered in source investigations. Simple public health advice may help to mitigate the risk of Legionella exposure in the domestic shower environment. Crown Copyright © 2016. Published by Elsevier GmbH. All rights reserved.

  12. Familial occurrence of pigment dispersion syndrome.

    Science.gov (United States)

    Bovell, A M; Damji, K F; Dohadwala, A A; Hodge, W G; Allingham, R R

    2001-02-01

    Pigment dispersion syndrome affects up to 4% of the white population. It is characterized by the presence of transillumination defects, Krukenberg's spindle and dense trabecular meshwork pigmentation. Open-angle glaucoma will develop in as many as 50% of affected patients. In this study we describe the familial occurrence of pigment dispersion syndrome in six North American pedigrees and the phenotypic characteristics with respect to pigment dispersion syndrome and glaucoma. Probands with pigment dispersion syndrome were identified in glaucoma clinics at university eye centres in Ottawa and Durham, NC. Families with two or more affected members were evaluated. All willing members in each family underwent a thorough clinical examination and were classified as affected with pigment dispersion syndrome, suspect or unaffected. The previous medical records were reviewed to obtain the past medical and ocular history, including risk factors for glaucoma. All six families are white. Three families show at least two generations of affected members. Of the 43 subjects examined 58% were women. All 14 affected members showed moderate to heavy trabecular meshwork pigmentation and either Krukenberg's spindle or transillumination defects. The affected members were also considerably more myopic (mean spherical equivalent for the right eye -4.72 dioptres) than the suspect group or the unaffected group (mean spherical equivalent -0.79 D and +1.19 D respectively) (p pigment dispersion syndrome. Our ultimate goal is to identify the gene(s) that causes this disorder in order to clarify its molecular etiology and pathophysiology. This may give rise to a molecular classification of the disease as well as provide the foundation for genetic testing and new treatment approaches.

  13. Integrating occurrence and detectability patterns based on interview data: a case study for threatened mammals in Equatorial Guinea

    Science.gov (United States)

    Martínez-Martí, Chele; Jiménez-Franco, María V.; Royle, J. Andrew; Palazón, José A.; Calvo, José F.

    2016-01-01

    Occurrence models that account for imperfect detection of species are increasingly used for estimating geographical range, for determining species-landscape relations and to prioritize conservation actions worldwide. In 2010, we conducted a large-scale survey in Río Muni, the mainland territory of Equatorial Guinea, which aimed to estimate the probabilities of occurrence and detection of threatened mammals based on environmental covariates, and to identify priority areas for conservation. Interviews with hunters were designed to record presence/absence data of seven species (golden cat, leopard, forest elephant, forest buffalo, western gorilla, chimpanzee and mandrill) in 225 sites throughout the region. We fitted single season occupancy models and recently developed models which also include false positive errors (i.e. species detected in places where it actually does not occur), which should provide more accurate estimates for most species, which are susceptible to mis-identification. Golden cat and leopard had the lowest occurrence rates in the region, whereas primates had the highest rates. All species, except gorilla, were affected negatively by human settlements. The southern half of Río Muni showed the highest occurrence of the species studied, and conservation strategies for ensuring the persistence of threatened mammals should be focused on this area.

  14. Lidocaine Patch (5%) in Treatment of Persistent Inguinal Postherniorrhaphy Pain

    DEFF Research Database (Denmark)

    Bischoff, Joakim M; Petersen, Marian; Uçeyler, Nurcan

    2013-01-01

    Evidence-based pharmacological treatment options for patients with persistent inguinal postherniorrhaphy pain are lacking.......Evidence-based pharmacological treatment options for patients with persistent inguinal postherniorrhaphy pain are lacking....

  15. Factors associated with persistent airflow limitation in severe asthma

    NARCIS (Netherlands)

    ten Brinke, A.; Zwinderman, A. H.; Sterk, P. J.; Rabe, K. F.; Bel, E. H.

    2001-01-01

    Persistent airflow limitation can develop in nonsmoking patients with asthma. However, the prevalence and risk factors for airways obstruction with incomplete reversibility in asthma are unknown. We assessed the prevalence of persistent airflow limitation (defined as postbronchodilator FEV(1) or

  16. A minimally invasive option for the treatment of persistent ...

    African Journals Online (AJOL)

    . Hospital, King Saud ... We present two patients with persistent esophageal leak after compli- .... easy, and quite effective in the management of persistent ... 6 Rakocz M, Mazar A, Varon D, Spierer S, Blinder D, Martinowitz U. Dental extractions ...

  17. Variable Persister Gene Interactions with (pppGpp for Persister Formation in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Shuang Liu

    2017-09-01

    Full Text Available Persisters comprise a group of phenotypically heterogeneous metabolically quiescent bacteria with multidrug tolerance and contribute to the recalcitrance of chronic infections. Although recent work has shown that toxin-antitoxin (TA system HipAB depends on stringent response effector (pppGppin persister formation, whether other persister pathways are also dependent on stringent response has not been explored. Here we examined the relationship of (pppGpp with 15 common persister genes (dnaK, clpB, rpoS, pspF, tnaA, sucB, ssrA, smpB, recA, umuD, uvrA, hipA, mqsR, relE, dinJ using Escherichia coli as a model. By comparing the persister levels of wild type with their single gene knockout and double knockout mutants with relA, we divided their interactions into five types, namely A “dependent” (dnaK, recA, B “positive reinforcement” (rpoS, pspF, ssrA, recA, C “antagonistic” (clpB, sucB, umuD, uvrA, hipA, mqsR, relE, dinJ, D “epistasis” (clpB, rpoS, tnaA, ssrA, smpB, hipA, and E “irrelevant” (dnaK, clpB, rpoS, tnaA, sucB, smpB, umuD, uvrA, hipA, mqsR, relE, dinJ. We found that the persister gene interactions are intimately dependent on bacterial culture age, cell concentrations (diluted versus undiluted culture, and drug classifications, where the same gene may belong to different groups with varying antibiotics, culture age or cell concentrations. Together, this study represents the first attempt to systematically characterize the intricate relationships among the different mechanisms of persistence and as such provide new insights into the complexity of the persistence phenomenon at the level of persister gene network interactions.

  18. Evidence synthesis on the occurrence, causes, consequences, prevention and management of bullying and harassment behaviours to inform decision making in the NHS

    OpenAIRE

    Illing, Jan; Carter, Madeline; Thompson, Neill; Crampton, Paul; Morrow, Gill; Howse, Jenny; Cooke, A.; Burford, Bryan

    2013-01-01

    Background\\ud Workplace bullying is a persistent problem in the NHS with negative implications for individuals, teams, and organisations. Bullying is a complex phenomenon and there is a lack of evidence on the best approaches to manage the problem.\\ud \\ud Aims\\ud Research questions\\ud \\ud What is known about the occurrence, causes, consequences and management of bullying and inappropriate behaviour in the workplace?\\ud \\ud Objectives\\ud Summarise the reported prevalence of workplace bullying ...

  19. Prediction of antibody persistency from antibody titres to natalizumab

    DEFF Research Database (Denmark)

    Jensen, Poul Erik H; Koch-Henriksen, Nils; Sellebjerg, Finn

    2012-01-01

    In a subgroup of patients with multiple sclerosis natalizumab therapy causes generation of anti-natalizumab antibodies that may be transient or persistent. It is recommended to discontinue natalizumab therapy in persistently antibody-positive patients.......In a subgroup of patients with multiple sclerosis natalizumab therapy causes generation of anti-natalizumab antibodies that may be transient or persistent. It is recommended to discontinue natalizumab therapy in persistently antibody-positive patients....

  20. Bilateral synchronous benign ovarian neoplasm: A rare occurrence ...

    African Journals Online (AJOL)

    Bilateral synchronous ovarian tumours are defined as the occurrence of two or more histologically distinct tumours in the ovaries. Synchronous tumours of the female genital tract are rare and the association of mature cystic teratoma with contralateral serous cystadenoma is uncommon. We report the rare occurrence of a ...

  1. Seasonal Variation in the Occurrence of Pregnancy-Induced ...

    African Journals Online (AJOL)

    Pregnancy-Induced Hypertension (PIH) is one of the leading causes of maternal, neonatal and infant mortality. Several studies have suggested that the occurrence of PIH may be dependent on environmental factors. Although, several countries have documented the prevalence of PIH, little is known about the occurrence ...

  2. Word and phoneme frequency of occurrence in conversational ...

    African Journals Online (AJOL)

    Frequency of occurrence of Setswana consonant phonemes in a conversational sample of 49 358 Setswana-words was deter- mined. The percentage of occurrence of each consonant in each of the three positions of words was found to be 53.9% in the initial, 41.8% in the medial and 4.1% in the final positions. In addition ...

  3. Forest Fire Occurrence in Southern Counties, 1966-1975

    Science.gov (United States)

    M.L. Doolittle

    1977-01-01

    Forest fire occurrence data for individual protection units generally are unavailable outside particular state organization. Number of fires, area protected and fire occurrence rate (fires per 1,000,000 acres) from 1966 to 1975, are presented in tables for the 993 counties under protection in 13 southern states. These data are compared with data for the preceeding...

  4. BEAM-BASED MEASUREMENTS OF PERSISTENT CURRENT DECAY IN RHIC

    International Nuclear Information System (INIS)

    FISCHER, W.; JAIN, A.; TEPIKIAN, S.

    2001-01-01

    The two RHIC rings are equipped with superconducting dipole magnets. At injection, induced persistent currents in these magnets lead to a sextupole component. As the persistent currents decay with time, the horizontal and vertical chromaticities change. From magnet measurements of persistent current decays, chromaticity changes in the machine are estimated and compared with chromaticity measurements

  5. Persistent Structural Priming from Language Comprehension to Language Production

    Science.gov (United States)

    Bock, Kathryn; Dell, Gary S.; Chang, Franklin; Onishi, Kristine H.

    2007-01-01

    To examine the relationship between syntactic processes in language comprehension and language production, we compared structural persistence from sentence primes that speakers heard to persistence from primes that speakers produced. [Bock, J. K., & Griffin, Z. M. (2000). The persistence of structural priming: transient activation or implicit…

  6. Bacterial persistence: some new insights into an old phenomenon

    Indian Academy of Sciences (India)

    PRAKASH KUMAR

    the involvement of the alarmone (p) ppGpp in the generation of persisters. However, the precise mechanisms are ... Bigger noticed that treatment of cultures of Staphylococcus aureus with high concentrations of ...... Li Y and Zhang Y 2007 pho U is a persister switch involved in persister formation and tolerance to multiple ...

  7. Volatility persistence in crude oil markets

    International Nuclear Information System (INIS)

    Charles, Amélie; Darné, Olivier

    2014-01-01

    Financial market participants and policy-makers can benefit from a better understanding of how shocks can affect volatility over time. This study assesses the impact of structural changes and outliers on volatility persistence of three crude oil markets – Brent, West Texas Intermediate (WTI) and Organization of Petroleum Exporting Countries (OPEC) – between January 2, 1985 and June 17, 2011. We identify outliers using a new semi-parametric test based on conditional heteroscedasticity models. These large shocks can be associated with particular event patterns, such as the invasion of Kuwait by Iraq, the Operation Desert Storm, the Operation Desert Fox, and the Global Financial Crisis as well as OPEC announcements on production reduction or US announcements on crude inventories. We show that outliers can bias (i) the estimates of the parameters of the equation governing volatility dynamics; (ii) the regularity and non-negativity conditions of GARCH-type models (GARCH, IGARCH, FIGARCH and HYGARCH); and (iii) the detection of structural breaks in volatility, and thus the estimation of the persistence of the volatility. Therefore, taking into account the outliers on the volatility modelling process may improve the understanding of volatility in crude oil markets. - Highlights: • We study the impact of outliers on volatility persistence of crude oil markets. • We identify outliers and patches of outliers due to specific events. • We show that outliers can bias (i) the estimates of the parameters of GARCH models, (ii) the regularity and non-negativity conditions of GARCH-type models, (iii) the detection of structural breaks in volatility of crude oil markets

  8. Report to Congress on abnormal occurrences, July--September 1992

    International Nuclear Information System (INIS)

    1992-12-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from July 1 through September 30, 1992. There were no abnormal occurrences at a nuclear power plant. Two abnormal occurrences involving medical misadministrations (both therapeutic) and one involving overexposure of a radiographer at NRC-licensed facilities were discussed in this report. In addition, another abnormal occurrence was reported by an NRC Agreement State. The report also contains information updating a previously reported abnormal occurrence

  9. Report to Congress on abnormal occurrences, April--June 1977

    International Nuclear Information System (INIS)

    1977-01-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report, the ninth in the series, covers the period from April 1 to June 30, 1977. The NRC has determined that during this period: there were two abnormal occurrences at the 64 nuclear power plants licensed to operate, one involved a breach of a plant's physical security system and the other involved degraded fuel rods; there were no abnormal occurrences at fuel cycle facilities (other than nuclear power plants); and there were two abnormal occurrences at other licensee facilities, one involved improper radioactive source handling procedures and the other involved overexposure of two radiographers. Information updating previously reported abnormal occurrences is also included

  10. Report to Congress on abnormal occurrences, January--March 1977

    International Nuclear Information System (INIS)

    1977-01-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report, the eighth in the series, covers the period from January 1 to March 31, 1977. The NRC has determined that during this period: there were no abnormal occurrences at the 63 nuclear power plants licensed to operate; there were no abnormal occurrences at fuel cycle facilities (other than nuclear power plants); and there was one abnormal occurrence at other licensee facilities. The event involved an inadvertent radiation exposure to two painters while working in an area where industrial radiography was being performed. This report also contains information updating previously reported abnormal occurrences

  11. Report to Congress on abnormal occurrences, January--March 1989

    International Nuclear Information System (INIS)

    1989-08-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health and safety and requires a Quarterly report of such events to be made to Congress. This report covers the period January 1 to March 31, 1989. For this reporting period, there were two abnormal occurrences at nuclear power plants licensed to operate. The first had generic implications and involved a plug failure resulting in a steam generator tube leak at North Anna Unit 1. The second involved a steam generator tube rupture at McGuire Unit 1. There were three abnormal occurrences under other NRC-issued licenses. Two involved medical therapy misadministrations and one involved a medical diagnostic misadministration. There were no abnormal occurrences reported by the Agreement States. The report also contains information updating some previously reported abnormal occurrences

  12. Report to Congress on abnormal occurrences, October--December 1991

    International Nuclear Information System (INIS)

    1992-03-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence of an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health and safety and requires a quarterly report of such events to be made to Congress. This report covers the period October through December 1991. Five abnormal occurrences at NRC-licensed facilities are discussed in this report. None of these occurrences involved a nuclear power plant. Four involved medical therapy misadministrations and one involved a medical diagnostic misadministration. The NRC's Agreement States reported three abnormal occurrences. Two involved exposures of non-radiation workers and one involved a medical therapy misadministration. The report also contains information that updates some previously reported abnormal occurrences

  13. Report to Congress on abnormal occurrences, April--June 1988

    International Nuclear Information System (INIS)

    1988-12-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from April 1 to June 30, 1988. For this reporting period, there were no abnormal occurrences at nuclear power plants licensed to operate. There were two abnormal occurrences at other NRC licensees: a significant breakdown in management and procedural controls at a medical facility and a medical diagnostic misadministration. There was one abnormal occurrence reported by an Agreement State (Texas) involving radioactive material released during a transportation accident. The report also contains information updating some previously reported abnormal occurrences

  14. Report to Congress on abnormal occurrences, July--September 1988

    International Nuclear Information System (INIS)

    1989-01-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from July 1 to September 30, 1988. For this reporting period, there were no abnormal occurrences at nuclear power plants licensed to operate. There were two abnormal occurrences under other NRC-issued licenses: multiple medical therapy misadministrations at a single hospital and a medical diagnostic misadministration. There was one abnormal occurrence reported by an Agreement State (Texas) involving a medical diagnostic misadministration. The report also contains information updating some previously reported abnormal occurrences

  15. MR imaging of persistent primitive trigeminal artery

    International Nuclear Information System (INIS)

    Ashikaga, Ryuichiro; Araki, Yutaka; Ono, Yukihiko; Ishida, Osamu; Mabuchi, Nobuhisa.

    1997-01-01

    The persistent trigeminal artery is the most common anomaly of the primitive carotid-vertebrobasilar anastomoses. We reviewed MR images and MR angiographies of 11 patients with primitive trigeminal artery. In 8 of the 11 cases, PTA were identified with conventional long TR spin-echo images. In 8 of 11 cases, a hypoplastic basilar trunk associated with PTA was seen on both MR images and MR angiographies. In 7 of 11 cases, a hypoplasia or agenesis of the ipsilateral posterior communicating artery was seen on MR angiographies. (author)

  16. Calculation of persistent currents in superconducting magnets

    Directory of Open Access Journals (Sweden)

    C. Völlinger

    2000-12-01

    Full Text Available This paper describes a semianalytical hysteresis model for hard superconductors. The model is based on the critical state model considering the dependency of the critical current density on the varying local field in the superconducting filaments. By combining this hysteresis model with numerical field computation methods, it is possible to calculate the persistent current multipole errors in the magnet taking local saturation effects in the magnetic iron parts into consideration. As an application of the method, the use of soft magnetic iron sheets (coil protection sheets mounted between the coils and the collars for partial compensation of the multipole errors during the ramping of the magnets is investigated.

  17. Trust and persistence for Internet resources

    Directory of Open Access Journals (Sweden)

    Maurizio Lunghi

    2013-01-01

    Full Text Available Internet has changed our way of working, communicating, living, producing and accessing information, everything available on an open and flexible infrastructure accessible to all the users mainly free of cost. However in some cases, it’s not only important to find information but also having information about its authenticity, integrity, provenance and relations with other pieces of information. Systems for certification using URN technology like the persistent identifiers for digital objects, for authors and for bodies can extremely help in order to refine the quality of information retrievable from Internet and to increase largely its usability and potential development.

  18. Persistently increased intestinal fraction of alkaline phosphatase

    DEFF Research Database (Denmark)

    Nathan, E; Baatrup, G; Berg, H

    1984-01-01

    Persistent elevation of the intestinal fraction of the alkaline phosphatase (API) as an isolated finding has to our knowledge not been reported previously. It was found in a boy followed during a period of 5.5 years. The only symptom was transient periodic fatigue observed at home, but not apparent...... during hospitalization. His blood type was O, RH+, Le (a-, b+) and he was a secretor of H-substance, which may be associated with rising API activity after fat-loading. In this case API was unchanged after fat-loading. Neither intestinal nor liver diseases were found, and no other cause for the elevated...

  19. Distributed design approach in persistent identifiers systems

    Science.gov (United States)

    Golodoniuc, Pavel; Car, Nicholas; Klump, Jens

    2017-04-01

    The need to identify both digital and physical objects is ubiquitous in our society. Past and present persistent identifier (PID) systems, of which there is a great variety in terms of technical and social implementations, have evolved with the advent of the Internet, which has allowed for globally unique and globally resolvable identifiers. PID systems have catered for identifier uniqueness, integrity, persistence, and trustworthiness, regardless of the identifier's application domain, the scope of which has expanded significantly in the past two decades. Since many PID systems have been largely conceived and developed by small communities, or even a single organisation, they have faced challenges in gaining widespread adoption and, most importantly, the ability to survive change of technology. This has left a legacy of identifiers that still exist and are being used but which have lost their resolution service. We believe that one of the causes of once successful PID systems fading is their reliance on a centralised technical infrastructure or a governing authority. Golodoniuc et al. (2016) proposed an approach to the development of PID systems that combines the use of (a) the Handle system, as a distributed system for the registration and first-degree resolution of persistent identifiers, and (b) the PID Service (Golodoniuc et al., 2015), to enable fine-grained resolution to different information object representations. The proposed approach solved the problem of guaranteed first-degree resolution of identifiers, but left fine-grained resolution and information delivery under the control of a single authoritative source, posing risk to the long-term availability of information resources. Herein, we develop these approaches further and explore the potential of large-scale decentralisation at all levels: (i) persistent identifiers and information resources registration; (ii) identifier resolution; and (iii) data delivery. To achieve large-scale decentralisation

  20. Persistence of innovation in unstable environments

    DEFF Research Database (Denmark)

    Suarez, Diana Valeria

    2014-01-01

    of the environment impact on the type of profitable innovations, and past innovations might not be suitable for the new environment. As a result, firm's innovative behavior might change, which means that the firm's set of decisions about engaging in the seek for innovations or not and, if so, the set of investments...... during 1998-2006, which coincides with a period of macroeconomic instability. Results suggest that persistence has to be analyzed in terms of a dynamic firm's innovative behavior - regardless of its results - and how it allows the firm to accumulate competences and resources, which increases the odds...... of successfully responding to changes in the environment and continuing to innovate....

  1. Grails Persistence with GORM and GSQL

    CERN Document Server

    Fischer, Robert

    2009-01-01

    Unique to the popular Grails web framework is its architecture. While other frameworks are built from the ground up, Grails leverages existing and proven technologies that already have advanced functionality built in. One of the key technologies in this architecture is Hibernate, on top of which Grails builds its GORM (Grails Object Relational Mapping) model layer. This provides Grails a persistence solution. Published with the developer in mind, firstPress technical briefs explore emerging technologies that have the potential to be critical for tomorrow's industry. Apress keeps developers one

  2. Neonatal thyrotoxicosis presenting as persistent pulmonary hypertension

    Science.gov (United States)

    Obeid, Rawad; Kalra, Vaneet Kumar; Arora, Prem; Quist, Felix; Moltz, Kathleen C; Chouthai, Nitin Shashikant

    2012-01-01

    Neonatal hyperthyroidism is a rare condition caused either by transplacental passage of thyroid-stimulating immunoglobulins from a mother with Graves’ disease or by activating mutations of the thyrotropin receptors and α-subunit of G-protein. The clinical features may vary. We report a case of neonatal thyrotoxicosis in an infant born to a mother with Graves’ disease, who presented with cardiorespiratory failure and persistent pulmonary hypertension (PPHN). PPHN resolved with specific antithyroid treatment and extracorporeal membrane oxygenation was not required. PMID:22669869

  3. Gravity in one dimension - Persistence of correlation

    International Nuclear Information System (INIS)

    Miller, B.N.; Reidl, C.J. Jr.

    1990-01-01

    Central questions are concerning the thermalization time-scale in a one-dimensional, self-gravitating system are addressed in the present consideration of the persistent correlation between the positions and velocities of the mass-sheets. An algorithm developed for testing thermalization in the one-dimensional gravitating system was applied to the logistic map as a control; the parameter value associated with global chaos yields complete agreement with theoretical prediction. The implications of these results for gravitational interaction in higher dimension should be considered. 26 refs

  4. Explaining evolution via constrained persistent perfect phylogeny

    Science.gov (United States)

    2014-01-01

    Background The perfect phylogeny is an often used model in phylogenetics since it provides an efficient basic procedure for representing the evolution of genomic binary characters in several frameworks, such as for example in haplotype inference. The model, which is conceptually the simplest, is based on the infinite sites assumption, that is no character can mutate more than once in the whole tree. A main open problem regarding the model is finding generalizations that retain the computational tractability of the original model but are more flexible in modeling biological data when the infinite site assumption is violated because of e.g. back mutations. A special case of back mutations that has been considered in the study of the evolution of protein domains (where a domain is acquired and then lost) is persistency, that is the fact that a character is allowed to return back to the ancestral state. In this model characters can be gained and lost at most once. In this paper we consider the computational problem of explaining binary data by the Persistent Perfect Phylogeny model (referred as PPP) and for this purpose we investigate the problem of reconstructing an evolution where some constraints are imposed on the paths of the tree. Results We define a natural generalization of the PPP problem obtained by requiring that for some pairs (character, species), neither the species nor any of its ancestors can have the character. In other words, some characters cannot be persistent for some species. This new problem is called Constrained PPP (CPPP). Based on a graph formulation of the CPPP problem, we are able to provide a polynomial time solution for the CPPP problem for matrices whose conflict graph has no edges. Using this result, we develop a parameterized algorithm for solving the CPPP problem where the parameter is the number of characters. Conclusions A preliminary experimental analysis shows that the constrained persistent perfect phylogeny model allows to

  5. Archway for Radiation and Micrometeorite Occurrence Resistance

    Science.gov (United States)

    Giersch, Louis R.

    2012-01-01

    The environmental conditions of the Moon require mitigation if a long-term human presence is to be achieved for extended periods of time. Radiation, micrometeoroid impacts, high-velocity debris, and thermal cycling represent threats to crew, equipment, and facilities. For decades, local regolith has been suggested as a candidate material to use in the construction of protective barriers. A thickness of roughly 3m is sufficient protection from both direct and secondary radiation from cosmic rays and solar protons; this thickness is sufficient to reduce radiation exposure even during solar flares. NASA has previously identified a need for innovations that will support lunar habitats using lightweight structures because the reduction of structural mass translates directly into additional up and down mass capability that would facilitate additional logistics capacity and increased science return for all mission phases. The development of non-pressurized primary structures that have synergy with the development of pressurized structures is also of interest. The use of indigenous or in situ materials is also a well-known and active area of research that could drastically improve the practicality of human exploration beyond low-Earth orbit. The Archway for Radiation and Micrometeorite Occurrence Resistance (ARMOR) concept is a new, multifunctional structure that acts as radiation shielding and micrometeorite impact shielding for long-duration lunar surface protection of humans and equipment. ARMOR uses a combination of native regolith and a deployed membrane jacket to yield a multifunctional structure. ARMOR is a robust and modular system that can be autonomously assembled on-site prior to the first human surface arrival. The system provides protection by holding a sufficiently thick (3 m) archshaped shell of local regolith around a central cavity. The regolith is held in shape by an arch-shaped jacket made of strong but deployable material. No regolith processing is

  6. Antimicrobial resistance dashboard application for mapping environmental occurrence and resistant pathogens.

    Science.gov (United States)

    Stedtfeld, Robert D; Williams, Maggie R; Fakher, Umama; Johnson, Timothy A; Stedtfeld, Tiffany M; Wang, Fang; Khalife, Walid T; Hughes, Mary; Etchebarne, Brett E; Tiedje, James M; Hashsham, Syed A

    2016-03-01

    An antibiotic resistance (AR) Dashboard application is being developed regarding the occurrence of antibiotic resistance genes (ARG) and bacteria (ARB) in environmental and clinical settings. The application gathers and geospatially maps AR studies, reported occurrence and antibiograms, which can be downloaded for offline analysis. With the integration of multiple data sets, the database can be used on a regional or global scale to identify hot spots for ARGs and ARB; track and link spread and transmission, quantify environmental or human factors influencing presence and persistence of ARG harboring organisms; differentiate natural ARGs from those distributed via human or animal activity; cluster and compare ARGs connections in different environments and hosts; and identify genes that can be used as proxies to routinely monitor anthropogenic pollution. To initially populate and develop the AR Dashboard, a qPCR ARG array was tested with 30 surface waters, primary influent from three waste water treatment facilities, ten clinical isolates from a regional hospital and data from previously published studies including river, park soil and swine farm samples. Interested users are invited to download a beta version (available on iOS or Android), submit AR information using the application, and provide feedback on current and prospective functionalities. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Citizen Science Program Shows Urban Areas Have Lower Occurrence of Frog Species, but Not Accelerated Declines.

    Directory of Open Access Journals (Sweden)

    Martin J Westgate

    Full Text Available Understanding the influence of landscape change on animal populations is critical to inform biodiversity conservation efforts. A particularly important goal is to understand how urban density affects the persistence of animal populations through time, and how these impacts can be mediated by habitat provision; but data on this question are limited for some taxa. Here, we use data from a citizen science monitoring program to investigate the effect of urbanization on patterns of frog species richness and occurrence over 13 years. Sites surrounded by a high proportion of bare ground (a proxy for urbanization had consistently lower frog occurrence, but we found no evidence that declines were restricted to urban areas. Instead, several frog species showed declines in rural wetlands with low-quality habitat. Our analysis shows that urban wetlands had low but stable species richness; but also that population trajectories are strongly influenced by vegetation provision in both the riparian zone and the wider landscape. Future increases in the extent of urban environments in our study area are likely to negatively impact populations of several frog species. However, existing urban areas are unlikely to lose further frog species in the medium term. We recommend that landscape planning and management focus on the conservation and restoration of rural wetlands to arrest current declines, and the revegetation of urban wetlands to facilitate the re-expansion of urban-sensitive species.

  8. Occurrence and distribution of organophosphorus flame retardants and plasticizers in anthropogenically affected groundwater.

    Science.gov (United States)

    Regnery, J; Püttmann, W; Merz, C; Berthold, G

    2011-02-01

    Occurrence and distribution of chlorinated and non-chlorinated organophosphates in 72 groundwater samples from Germany under different recharge/infiltration conditions were investigated. Tris(2-chloro-1-methylethyl) phosphate (TCPP) and tris(2-chloroethyl) phosphate (TCEP) were the most frequently detected organophosphates in groundwater samples. Highest individual organophosphate concentrations (>0.1 µg L(-1)) were determined in groundwater polluted by infiltrating leachate and groundwater recharged via riverbank filtration of organophosphate-loaded recipients. In samples from springs and deep groundwater monitoring wells that are not affected by surface waters, organophosphate concentrations were mostly below the limit of detection. The occurrence (3-9 ng L(-1)) of TCPP and TCEP in samples from aquifers with groundwater ages between 20 and 45 years indicates the persistence of both compounds within the aquifer. At urban sites organophosphate-loaded precipitation, surface runoff, and leakage of wastewater influenced groundwater quality. For rural sites, where groundwater recharge is only influenced by precipitation, organophosphates were very rarely detectable in groundwater.

  9. Stability, occurrence and step morphology of polymorphs and polytypes of stearic acid. I. Stability and occurrence

    Science.gov (United States)

    Sato, Kiyotaka; Kobayashi, Masamichi; Morishita, Hirofumi

    1988-02-01

    The thermodynamical stability and occurrence of three different structural modifications: monoclinic and pseudo-orthorhombic polytypes of the B polymorph, called B(mon) and B(orth II) respectively, and monoclinic C polymorph, C(mon), of stearic acid have been examined. The solubility measurements, overgrowth and isothermal crystallization proved that B(orth II) and C(mon) are most stable below and above 32°C, respectively, whereas B(mon) is always metastable, turning to be more stable than C(mon) below between 23 and 24°C. It was confirmed by micro-probe Raman spectroscopy that the polytypic structure of the newly-overgrown crystal on the (001) faces of the seed crystal of B(mon) changed from the original monoclinic to pseudo-orthorhombic, B(orth II), at very small supersaturations above 23°C. This conversion was caused by the solubility difference. The occurrence experiment indicated a slight tendency that B(mon) crystallized more than B(orth II) at lower temperatures.

  10. Gate-controlled switching between persistent and inverse persistent spin helix states

    International Nuclear Information System (INIS)

    Yoshizumi, K.; Sasaki, A.; Kohda, M.; Nitta, J.

    2016-01-01

    We demonstrate gate-controlled switching between persistent spin helix (PSH) state and inverse PSH state, which are detected by quantum interference effect on magneto-conductance. These special symmetric spin states showing weak localization effect give rise to a long spin coherence when the strength of Rashba spin-orbit interaction (SOI) is close to that of Dresselhaus SOI. Furthermore, in the middle of two persistent spin helix states, where the Rashba SOI can be negligible, the bulk Dresselhaus SOI parameter in a modulation doped InGaAs/InAlAs quantum well is determined.

  11. Gate-controlled switching between persistent and inverse persistent spin helix states

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizumi, K.; Sasaki, A.; Kohda, M.; Nitta, J. [Department of Materials Science, Tohoku University, Sendai 980-8579 (Japan)

    2016-03-28

    We demonstrate gate-controlled switching between persistent spin helix (PSH) state and inverse PSH state, which are detected by quantum interference effect on magneto-conductance. These special symmetric spin states showing weak localization effect give rise to a long spin coherence when the strength of Rashba spin-orbit interaction (SOI) is close to that of Dresselhaus SOI. Furthermore, in the middle of two persistent spin helix states, where the Rashba SOI can be negligible, the bulk Dresselhaus SOI parameter in a modulation doped InGaAs/InAlAs quantum well is determined.

  12. THE OCCURRENCE OF DISINFECTION BY-PRODUCTS OF HEALTH CONCERN IN DRINKING WATER: RESULTS OF A NATIONWIDE DBP OCCURRENCE STUDY

    Science.gov (United States)

    The motivation for this Nationwide Disinfection By-product (DBP) Occurrence Study was two-fold: First, more than 500 DBPs have been reported in the literature, yet there is almost no quantitative occurrence information for most. As a result, there is significant uncertainty ove...

  13. Understanding the Occurrence and Transport of Current-use Pesticides in the San Francisco Estuary Watershed

    Directory of Open Access Journals (Sweden)

    Kathryn Kuivila

    2008-10-01

    Full Text Available The occurrence and potential effects of current-use pesticides are of concern in the San Francisco Estuary watershed but our understanding of the spatial and temporal distribution of contamination is limited. This paper summarizes almost two decades of historical data and uses it to describe our current knowledge of the processes controlling the occurrence of current-use pesticides in the watershed. Monitoring studies analyze fewer than half of the pesticides applied in the watershed and most of our knowledge is about inputs of dissolved pesticides in the upper watershed. The four major seasonal patterns of riverine inputs of pesticides to the estuary can be identified by usage and transport mechanism. Dormant spray insecticides applied to orchards and herbicides applied to a variety of crops are transported by rainfall during the winter. Alfalfa pesticides are detected following rainfall and irrigation return flow in the spring, and rice pesticides are detected following release of rice field water in the summer. Irrigation return flows transport a variety of herbicides during the summer. In addition, pesticides applied on Delta islands can cause elevated pesticide concentrations in localized areas. Although not as well characterized, urban creeks appear to have their own patterns of insecticide concentrations causing toxicity throughout most of the year. Current-use pesticides have also been detected on suspended and bed sediments throughout the watershed but limited data make it difficult to determine occurrence patterns. Data gaps include the lack of analysis of many pesticides (or degradates, changing pesticide use, limited information on pesticide transport within the Delta, and an incomplete understanding of the transport and persistence of sediment-associated pesticides. Future monitoring programs should be designed to address these data gaps.

  14. Estimates of connectivity reveal non-equilibrium epiphyte occurrence patterns almost 180 years after habitat decline.

    Science.gov (United States)

    Johansson, Victor; Snäll, Tord; Ranius, Thomas

    2013-06-01

    Habitat loss is a major cause of species decline and extinction. Immediately after habitat loss, species occurrences are not in equilibrium with the new landscape and more closely reflect the previous landscape structure. Species with slow colonisation-extinction dynamics may display long time-lags before reaching a new equilibrium. We investigated the importance of connectivity to current and historical dispersal sources with the aim of explaining the occurrence pattern of epiphytic lichens with different traits among 104 old oaks. We used oak survey data collected from 1830 and 2009 for a Swedish landscape where oak densities declined drastically shortly after 1830. We fitted a commonly used connectivity measure and estimated the confidence interval for the spatial scale parameter. Small differences in the spatial scale parameter resulted in large differences in model fit. Connectivity to trees in 1830 better explained the occurrence of three of the four species compared to the connectivity in 2009. The explanatory power of the historical landscape structure was highest for the species with traits that may result in a low colonisation rate--both a narrow niche (here few suitable trees) and large dispersal propagules. The results suggest that oak-dependent epiphytic lichens have not reached equilibrium with the spatial landscape structure 180 years after the drastic decline in habitat. For the long-term persistence of epiphytes associated with old trees, conservation efforts should focus on (1) protecting and restoring stands where specialised species with large dispersal propagules (i.e. with low colonisation rates) occur today and (2) promoting tree regeneration in their near vicinity.

  15. Wildlife in the Matrix: Spatio-Temporal Patterns of Herbivore Occurrence in Karnataka, India

    Science.gov (United States)

    Karanth, Krithi K.

    2016-01-01

    Wildlife reserves are becoming increasingly isolated from the surrounding human-dominated landscapes particularly in Asia. It is imperative to understand how species are distributed spatially and temporally in and outside reserves, and what factors influence their occurrence. This study surveyed 7500 km2 landscape surrounding five reserves in the Western Ghats to examine patterns of occurrence of five herbivores: elephant, gaur, sambar, chital, and pig. Species distributions are modeled spatio-temporally using an occupancy approach. Trained field teams conducted 3860 interview-based occupancy surveys in a 10-km buffer surrounding these five reserves in 2012. I found gaur and wild pig to be the least and most wide-ranging species, respectively. Elephant and chital exhibit seasonal differences in spatial distribution unlike the other three species. As predicted, distance to reserve, the reserve itself, and forest cover were associated with higher occupancy of all species, and higher densities of people negatively influenced occurrence of all species. Park management, species protection, and conflict mitigation efforts in this landscape need to incorporate temporal and spatial understanding of species distributions. All species are known crop raiders and conflict prone locations with resources (such as water and forage) have to be monitored and managed carefully. Wildlife reserves and adjacent areas are critical for long-term persistence and habitat use for all five herbivores and must be monitored to ensure wildlife can move freely. Such a large-scale approach to map and monitor species distributions can be adapted to other landscapes to identify and monitor critical habitats shared by people and wildlife.

  16. PERSISTENT ORGANIC POLLUTANS (POPS DAN KONVENSI STOCKHOLM

    Directory of Open Access Journals (Sweden)

    Lina Warlina

    2010-07-01

    Full Text Available Persistent organic pollutants (POPs are toxic chemicals that adversely affect human health and the environment around the world. Because they can be transported by wind and water, most POPs generated in one country can affect people and wildlife far from where they are used and released. They persist for long periods of time in the environment and can accumulate and pass from one species to the next through the food chain. To address this global concern, many countries in the world joined forces with 90 other countries and the European Community to sign a groundbreaking United Nations treaty in Stockholm, Sweden, in May 2001, known as the Stockholm Convention. One of important agreement is all countries agreed to reduce or eliminate the production, use, and/or release of 12 key POPs. The Convention specifies a scientific review process that could lead to the addition of other POPs chemicals of global concern. POPs include a range of substances that include intentionally produced chemicals currently or once used in agriculture, disease control, manufacturing, or industrial processes. Also it can be produced by unintentionally produced chemicals, such as dioxins, that result from some industrial processes and from combustion (for example, municipal and medical waste incineration and backyard burning of trash.

  17. Persistent viral infections and immune aging.

    Science.gov (United States)

    Brunner, Stefan; Herndler-Brandstetter, Dietmar; Weinberger, Birgit; Grubeck-Loebenstein, Beatrix

    2011-07-01

    Immunosenescence comprises a set of dynamic changes occurring to both, the innate as well as the adaptive immune system that accompany human aging and result in complex manifestations of still poorly defined deficiencies in the elderly population. One of the most prominent alterations during aging is the continuous involution of the thymus gland which is almost complete by the age of 50. Consequently, the output of naïve T cells is greatly diminished in elderly individuals which puts pressure on homeostatic forces to maintain a steady T cell pool for most of adulthood. In a great proportion of the human population, this fragile balance is challenged by persistent viral infections, especially Cytomegalovirus (CMV), that oblige certain T cell clones to monoclonally expand repeatedly over a lifetime which then occupy space within the T cell pool. Eventually, these inflated memory T cell clones become exhausted and their extensive accumulation accelerates the age-dependent decline of the diversity of the T cell pool. As a consequence, infectious diseases are more frequent and severe in elderly persons and immunological protection following vaccination is reduced. This review therefore aims to shed light on how various types of persistent viral infections, especially CMV, influence the aging of the immune system and highlight potential measures to prevent the age-related decline in immune function. Copyright © 2010 Elsevier B.V. All rights reserved.

  18. Cosmic radiation exposure and persistent cognitive dysfunction

    Science.gov (United States)

    Parihar, Vipan K.; Allen, Barrett D.; Caressi, Chongshan; Kwok, Stephanie; Chu, Esther; Tran, Katherine K.; Chmielewski, Nicole N.; Giedzinski, Erich; Acharya, Munjal M.; Britten, Richard A.; Baulch, Janet E.; Limoli, Charles L.

    2016-01-01

    The Mars mission will result in an inevitable exposure to cosmic radiation that has been shown to cause cognitive impairments in rodent models, and possibly in astronauts engaged in deep space travel. Of particular concern is the potential for cosmic radiation exposure to compromise critical decision making during normal operations or under emergency conditions in deep space. Rodents exposed to cosmic radiation exhibit persistent hippocampal and cortical based performance decrements using six independent behavioral tasks administered between separate cohorts 12 and 24 weeks after irradiation. Radiation-induced impairments in spatial, episodic and recognition memory were temporally coincident with deficits in executive function and reduced rates of fear extinction and elevated anxiety. Irradiation caused significant reductions in dendritic complexity, spine density and altered spine morphology along medial prefrontal cortical neurons known to mediate neurotransmission interrogated by our behavioral tasks. Cosmic radiation also disrupted synaptic integrity and increased neuroinflammation that persisted more than 6 months after exposure. Behavioral deficits for individual animals correlated significantly with reduced spine density and increased synaptic puncta, providing quantitative measures of risk for developing cognitive impairment. Our data provide additional evidence that deep space travel poses a real and unique threat to the integrity of neural circuits in the brain. PMID:27721383

  19. PERSISTENCE MAPPING USING EUV SOLAR IMAGER DATA

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, B. J. [NASA Goddard Space Flight Center, Code 671, Greenbelt, MD 20771 (United States); Young, C. A., E-mail: barbara.j.thompson@nasa.gov [NASA Goddard Space Flight Center, Code 670, Greenbelt, MD 20771 (United States)

    2016-07-01

    We describe a simple image processing technique that is useful for the visualization and depiction of gradually evolving or intermittent structures in solar physics extreme-ultraviolet imagery. The technique is an application of image segmentation, which we call “Persistence Mapping,” to isolate extreme values in a data set, and is particularly useful for the problem of capturing phenomena that are evolving in both space and time. While integration or “time-lapse” imaging uses the full sample (of size N ), Persistence Mapping rejects ( N − 1)/ N of the data set and identifies the most relevant 1/ N values using the following rule: if a pixel reaches an extreme value, it retains that value until that value is exceeded. The simplest examples isolate minima and maxima, but any quantile or statistic can be used. This paper demonstrates how the technique has been used to extract the dynamics in long-term evolution of comet tails, erupting material, and EUV dimming regions.

  20. Microbial Biofilms: Persisters, Tolerance and Dosing

    Science.gov (United States)

    Cogan, N. G.

    2005-03-01

    Almost all moist surfaces are colonized by microbial biofilms. Biofilms are implicated in cross-contamination of food products, biofouling, medical implants and various human infections such as dental cavities, ulcerative colitis and chronic respiratory infections. Much of current research is focused on the recalcitrance of biofilms to typical antibiotic and antimicrobial treatments. Although the polymer component of biofilms impedes the penetration of antimicrobials through reaction-diffusion limitation, this does not explain the observed tolerance, it merely delays the action of the agent. Heterogeneities in growth-rate also slow the eradication of the bacteria since most antimicrobials are far less effective for non-growing, or slowly growing bacteria. This also does not fully describe biofilm tolerance, since heterogeneities arr primairly a result of nutrient consumption. In this investigation, we describe the formation of `persister' cells which neither grow nor die in the presence of antibiotics. We propose that the cells are of a different phenotype than typical bacterial cells and the expression of the phenotype is regulated by the growth rate and the antibiotic concentration. We describe several experiments which describe the dynamics of persister cells and which motivate a dosing protocol that calls for periodic dosing of the population. We then introduce a mathematical model, which describes the effect of such a dosing regiment and indicates that the relative dose/withdrawal times are important in determining the effectiveness of such a treatment. A reduced model is introduced and the similar behavior is demonstrated analytically.

  1. Accuracy of circulating histones in predicting persistent organ failure and mortality in patients with acute pancreatitis.

    Science.gov (United States)

    Liu, T; Huang, W; Szatmary, P; Abrams, S T; Alhamdi, Y; Lin, Z; Greenhalf, W; Wang, G; Sutton, R; Toh, C H

    2017-08-01

    Early prediction of acute pancreatitis severity remains a challenge. Circulating levels of histones are raised early in mouse models and correlate with disease severity. It was hypothesized that circulating histones predict persistent organ failure in patients with acute pancreatitis. Consecutive patients with acute pancreatitis fulfilling inclusion criteria admitted to Royal Liverpool University Hospital were enrolled prospectively between June 2010 and March 2014. Blood samples were obtained within 48 h of abdominal pain onset and relevant clinical data during the hospital stay were collected. Healthy volunteers were enrolled as controls. The primary endpoint was occurrence of persistent organ failure. The predictive values of circulating histones, clinical scores and other biomarkers were determined. Among 236 patients with acute pancreatitis, there were 156 (66·1 per cent), 57 (24·2 per cent) and 23 (9·7 per cent) with mild, moderate and severe disease respectively, according to the revised Atlanta classification. Forty-seven healthy volunteers were included. The area under the receiver operating characteristic (ROC) curve (AUC) for circulating histones in predicting persistent organ failure and mortality was 0·92 (95 per cent c.i. 0·85 to 0·99) and 0·96 (0·92 to 1·00) respectively; histones were at least as accurate as clinical scores or biochemical markers. For infected pancreatic necrosis and/or sepsis, the AUC was 0·78 (0·62 to 0·94). Histones did not predict or correlate with local pancreatic complications, but correlated negatively with leucocyte cell viability (r = -0·511, P = 0·001). Quantitative assessment of circulating histones in plasma within 48 h of abdominal pain onset can predict persistent organ failure and mortality in patients with acute pancreatitis. Early death of immune cells may contribute to raised circulating histone levels in acute pancreatitis. © 2017 The Authors. BJS published by John Wiley & Sons Ltd on behalf of BJS

  2. Persistence of Women in Online Degree-Completion Programs

    Directory of Open Access Journals (Sweden)

    Terry Müller

    2008-06-01

    Full Text Available Although online courses at postsecondary institutions promise adults access, flexibility, and convenience, many barriers to online learning remain. This article presents findings from a qualitative case study, which explored the phenomenon of undergraduate and graduate women learners’ persistence in online degree-completion programs at a college in the Northeast of the United States. Research questions asked why women learners persisted or failed to persist, and how factors supporting or hindering persistence influenced learners. Interviews with a purposeful sample of 20 participants revealed the complexity of variables affecting learners’ persistence to graduation. Findings suggested that multiple responsibilities, insufficient interaction with faculty, technology, and coursework ranked highest as barriers to women’s persistence. Strong motivation to complete degrees, engagement in the learning community, and appreciation for the convenience of an online degree-completion option facilitated persistence.

  3. Technical assistance contractor occurrence reporting and processing system

    International Nuclear Information System (INIS)

    1996-08-01

    Members of the Uranium Mill Tailings Remedial Action (UMTRA) Project Technical Assistance Contractor (TAC) are responsible to notify management of TAC occurrence reporting and processing system (ORPS) classified occurrences .An ORPS occurrence is an unexpected or unplanned event on DOE property which causes bodily harm, death, damage to government property, exposure to toxic or hazardous substances above acceptable limits to workers, the environment, or general public. Examples of potential reportable occurrences include, but not limited to, site personnel exposures to airborne contaminants, incidents which could expose the general public to high levels of radiation or other contaminants, a vehicle accident resulting in property damage or personnel injuries. Listed TAC manager/staff contacts, with the assistance of TAC ORPS Program Coordinators, will determine if the occurrence is reportable under Department of Energy (DOE) Order M 232.1-2. The reportable occurrences will be classified as emergency, unusual, or off-normal. If determined to be reportable, listed TAC manager/staff will verbally report the details of the occurrence to the DOE Duty Officer within 2 hours of initial notification, and provide a written report of the event by noon the following work day

  4. Occurrence, fate and transformation of emerging contaminants in water: An overarching review of the field

    International Nuclear Information System (INIS)

    Wilkinson, John; Hooda, Peter S.; Barker, James; Barton, Stephen; Swinden, Julian

    2017-01-01

    Many of the products and drugs used commonly contain chemical components which may persist through sewage treatment works (STW) and eventually enter the aquatic environment as parent compounds, metabolites, or transformation products. Pharmaceuticals and personal care products (PPCPs) and other emerging contaminants (ECs) have been detected in waters (typically ng/L) as well as more recently bound to sediment and plastic particles (typically ng/g). Despite significant advancement of knowledge since the late 1990s, the fate of these contaminants/transformation products once introduced into the aquatic environment remains relatively unresolved. This review provides a unique focus on the fate of seven major groups of PPCPs/ECs in the aquatic environment, which is frequently not found in similar works which are often compound or topic-specific and limited in background knowledge. Key findings include: a) some replacements for regulation precluded/banned chemicals may be similarly persistent in the environment as those they replace, b) the adsorption of potentially bioactive chemicals to micro- and nanoplastics is a significant topic with risks to aquatic organisms potentially greater than previously thought, and c) micro-/nanoplastics are likely to remain of significant concern for centuries after regulatory limitations on their use become active due to the slow degradation of macro-plastics into smaller components. An interdisciplinary perspective on recent advances in the field is presented here in a unique way which highlights both the principle science and direction of research needed to elucidate the fate and transport patterns of aquatic PPCPs/ECs. Unlike similar reviews, which are often topic-specific, here we aim to present an overarching review of the field with focus on the occurrence, transformation and fate of emerging contaminants. Environmental presence of seven major classes of contaminants (analygesics, antibiotics, antineoplastics, beta

  5. Equinoctial spread-F occurrence at low latitudes in different longitude sectors under moderate and high solar activity

    Science.gov (United States)

    Pietrella, M.; Pezzopane, M.; Fagundes, P. R.; de Jesus, R.; Supnithi, P.; Klinngam, S.; Ezquer, R. G.; Cabrera, M. A.

    2017-11-01

    A comparative study aimed to investigate the equatorial and low-latitude spread-F occurrences for moderate solar activity (MSA) and high solar activity (HSA), was carried out considering concurrent observations made in some ionospheric stations, which identify three separate longitudinal sectors: Chiang Mai (CGM; 18.8° N, 98.9° E, mag. Lat. 13.2° N) and Chumphon (CPN; 10.7° N, 99.4° E, mag. Lat. 3.2° N), Thailand; Palmas (PAL; 10.2° S, 311.8° E, mag. Lat. 0.9° S) and São José dos Campos (SJC; 23.2° S, 314.1° E, mag. Lat. 14.0° S), Brazil; Tucumán (TUC; 26.9° S, 294.6° E, mag. Lat. 16.8° S), Argentina. Spread-F phenomena recorded during the equinoctial months of September and October 2010, March and April 2011, for MSA, March and April 2014, September and October 2014, for HSA, were classified in two different modes: range spread-F (RSF) and frequency spread-F (FSF). The satellite trace (ST) occurrence was also investigated as possible precursor of spread-F events. When comparing the results of equatorial (CPN and PAL) and low-latitude (CGM, SJC, and TUC) stations, some common features independently of the solar activity emerge: (1) a prevalence of RSF signatures is observed in the time interval 20:00-03:00 LT, while FSF occurrences prevail in the time interval 03:00-06:00 LT; (2) STs are confirmed to be a possible precursor of RSF occurrences. For HSA, at equatorial latitudes, spread-F occurrences in the Thai sector (CPN) are higher than those observed in the Brazilian sector (PAL). When comparing the results of low-latitude stations of CGM, SJC, and TUC some unusual aspects characterizing the morphology of spread-F occurrences emerge: (1) contrary to the Thai and Argentine sectors, in the Brazilian sector (SJC), RSF and FSF appearances in September, for HSA, are observed with relatively long persistence times between about 03:00-06:00 LT and 01:00-03:00 LT respectively, while balanced RSF and FSF occurrences with short persistence times are

  6. On the probability of occurrence of rogue waves

    Directory of Open Access Journals (Sweden)

    E. M. Bitner-Gregersen

    2012-03-01

    Full Text Available A number of extreme and rogue wave studies have been conducted theoretically, numerically, experimentally and based on field data in the last years, which have significantly advanced our knowledge of ocean waves. So far, however, consensus on the probability of occurrence of rogue waves has not been achieved. The present investigation is addressing this topic from the perspective of design needs. Probability of occurrence of extreme and rogue wave crests in deep water is here discussed based on higher order time simulations, experiments and hindcast data. Focus is given to occurrence of rogue waves in high sea states.

  7. Swimming and Persons with Mild Persistant Asthma

    Directory of Open Access Journals (Sweden)

    Mirjana Arandelovic

    2007-01-01

    Full Text Available The aim of our study was to analyze the effect of recreational swimming on lung function and bronchial hyperresponsiveness (BHR in patients with mild persistent asthma. This study included 65 patients with mild persistent asthma, who were divided into two groups: experimental group A (n = 45 and control group B (n = 20. Patients from both groups were treated with low doses of inhaled corticosteroids (ICS and short-acting β2 agonists salbutamol as needed. Our program for patients in group A was combined asthma education with swimming (twice a week on a 1-h basis for the following 6 months. At the end of the study, in Group A, we found a statistically significant increase of lung function parameters FEV1 (forced expiratory volume in 1 sec (3.55 vs. 3.65 (p < 0.01, FVC (forced vital capacity (4.27 vs. 4.37 (p < 0.05, PEF (peak expiratory flow (7.08 vs. 7.46 (p < 0.01, and statistically significant decrease of BHR (PD20 0.58 vs. 2.01 (p < 0.001. In Group B, there was a statistically significant improvement of FEV1 3.29 vs. 3.33 (p < 0.05 and although FVC, FEV1/FVC, and PEF were improved, it was not significant. When Groups A and B were compared at the end of the study, there was a statistically significant difference of FVC (4.01 vs. 4.37, FEV1 (3.33 vs. 3.55, PEF (6.79 vs.7.46, and variability (p <0.001, and statistically significantly decreased BHR in Group A (2.01 vs. 1.75 (p < 0.001. Engagement of patients with mild persistent asthma in recreational swimming in nonchlorinated pools, combined with regular medical treatment and education, leads to better improvement of their parameters of lung function and also to more significant decrease of their airway hyperresponsiveness compared to patients treated with traditional medicine

  8. Persistent Identifiers, Discoverability and Open Science (Communication)

    Science.gov (United States)

    Murphy, Fiona; Lehnert, Kerstin; Hanson, Brooks

    2016-04-01

    Early in 2016, the American Geophysical Union announced it was incorporating ORCIDs into its submission workflows. This was accompanied by a strong statement supporting the use of other persistent identifiers - such as IGSNs, and the CrossRef open registry 'funding data'. This was partly in response to funders' desire to track and manage their outputs. However the more compelling argument, and the reason why the AGU has also signed up to the Center for Open Science's Transparency and Openness Promotion (TOP) Guidelines (http://cos.io/top), is that ultimately science and scientists will be the richer for these initiatives due to increased opportunities for interoperability, reproduceability and accreditation. The AGU has appealed to the wider community to engage with these initiatives, recognising that - unlike the introduction of Digital Object Identifiers (DOIs) for articles by CrossRef - full, enriched use of persistent identifiers throughout the scientific process requires buy-in from a range of scholarly communications stakeholders. At the same time, across the general research landscape, initiatives such as Project CRediT (contributor roles taxonomy), Publons (reviewer acknowledgements) and the forthcoming CrossRef DOI Event Tracker are contributing to our understanding and accreditation of contributions and impact. More specifically for earth science and scientists, the cross-functional Coalition for Publishing Data in the Earth and Space Sciences (COPDESS) was formed in October 2014 and is working to 'provide an organizational framework for Earth and space science publishers and data facilities to jointly implement and promote common policies and procedures for the publication and citation of data across Earth Science journals'. Clearly, the judicious integration of standards, registries and persistent identifiers such as ORCIDs and International Geo Sample Numbers (IGSNs) to the research and research output processes is key to the success of this venture

  9. Stability under persistent perturbation by white noise

    International Nuclear Information System (INIS)

    Kalyakin, L

    2014-01-01

    Deterministic dynamical system which has an asymptotical stable equilibrium is considered under persistent perturbation by white noise. It is well known that if the perturbation does not vanish in the equilibrium position then there is not Lyapunov's stability. The trajectories of the perturbed system diverge from the equilibrium to arbitrarily large distances with probability 1 in finite time. New concept of stability on a large time interval is discussed. The length of interval agrees the reciprocal quantity of the perturbation parameter. The measure of stability is the expectation of the square distance from the trajectory till the equilibrium position. The method of parabolic equation is applied to both estimate the expectation and prove such stability. The main breakthrough is the barrier function derived for the parabolic equation. The barrier is constructed by using the Lyapunov function of the unperturbed system

  10. Persistent Organic Pollutants and Type 2 Diabetes

    DEFF Research Database (Denmark)

    Wu, Hongyu; Bertrand, Kimberly A; Choi, Anna L

    2013-01-01

    and summarize existing evidence in a meta-analysis. METHODS: Plasma polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethylene (DDE), and hexachlorobenzene (HCB) concentrations were measured in 1,095 women who were free of diabetes at blood draw in 1989......BACKGROUND: Prospective data regarding persistent organic pollutants (POPs) and risk of type 2 diabetes (T2D) are limited, and the results for individual POPs are not entirely consistent across studies. OBJECTIVES: To prospectively examine plasma POP concentrations in relation to incident T2D......-1990 and participated in two case-control studies in the Nurses' Health Study. We identified 48 incident T2D cases through June 30, 2008. We conducted a literature search in MEDLINE and EMBASE through December 2011 to identify prospective studies on POPs in relation to diabetes. We used a fixed-effects model...

  11. Cognitive implications of facilitating echoic persistence.

    Science.gov (United States)

    Baldwin, Carryl L

    2007-06-01

    Seventeen participants performed a tone-pattern-matching task at different presentation levels while concurrently engaged in a simulated-driving task. Presentation levels of 60, 65, and 70 dBC (SPL) were combined factorially with tone-matching delays of 2, 3, and 4 sec. Intensity had no effect on performance in single-task conditions and short-delay conditions. However, when the participants were engaged concurrently in the driving task, a significant interaction between presentation level and delay was observed. In the longest delay condition, the participants performed the tone-pattern-matching task more efficiently (more quickly and without additional errors) as presentation intensity increased. These findings demonstrate the interaction between sensory and cognitive processes and point to a direct-intensity relationship where intensity affects the persistence of echoic memory. Implications for facilitating auditory processing and improving auditory interfaces in complex systems (i.e., transportation environments), particularly for older and hearing-impaired listeners, are discussed.

  12. Persistent organic pollutants in the Muda area

    International Nuclear Information System (INIS)

    Zuriati Zakaria; Md Pauzi Abdullah; Laily Din

    2002-01-01

    A screening for the presence of Persistent Organic Pollutants (POP) in Malaysia was undertaken by the Universiti Kebangsaan Malaysia as part of the Department of Environment's assessment process to study the extent of bioaccumulation or the transboundary effect of POPs in the country. Water, sediment and fish samples were tested for the presence of nine compounds which were aldrin, dieldrin, chlordane, DDT, hexachlordane, hexachlorobenzene, mirex, toxaphene and heptachlor. The Muda area was one of the areas investigated where samplings were conducted at Sungai Tajar, Sungai Tala and Sungai Fadang. Analyses of the samples showed that residues of DDT, aldrin, dieldrin, endrin and BHC were present in the sediment.The water samples also showed the presence of aldrin and dieldrin. (Author)

  13. Remote Biometrics for Robust Persistent Authentication

    DEFF Research Database (Denmark)

    Ingwar, Mads Ingerslew; Jensen, Christian D.

    2014-01-01

    This paper examines the problem of providing a robust non-invasive authentication service for mobile users in a smart environment. We base our work on the persistent authentication model (PAISE), which relies on available sensors to track principals from the location where they authenticate, e.......g., through a smart card based access control system, to the location where the authentication is required by a location-based service. The PAISE model is extended with remote biometrics to prevent the decay of authentication confidence when authenticated users encounter and interact with other users...... in the environment. The result is a calm approach to authentication, where mobile users are transparently authenticated towards the system, which allows the provision of location-based services. The output of the remote biometrics are fused using error-rate-based fusion to solve a common problem that occurs in score...

  14. Persistence of malathion residues in stored wheat

    International Nuclear Information System (INIS)

    Farghaly, M.; Zayed, S.M.A.D.

    1990-01-01

    The persistence of succinate- 14 C-malathion in stored wheat was investigated under local conditions during a storage period of 32 weeks. The insecticide penetrated readily into the seed and up to 16% of the applied dose was found to be bound after 32 weeks in storage. Total terminal residues declined to 9.3 and 21.0 mg/kg from initially applied doses of 12.2 and 24.4 mg/kg respectively. A small percentage of malaoxon was detected only during the early weeks after treatment (3-5%). Malathion was the major constituent of the extractable residues. In addition, seven degradation products were detected and identified. (author). 6 refs, 2 figs, 2 tabs

  15. Persisting effect of community approaches to resuscitation

    DEFF Research Database (Denmark)

    Nielsen, Anne Møller; Isbye, Dan Lou; Lippert, Freddy Knudsen

    2014-01-01

    BACKGROUND: On the Danish island of Bornholm an intervention was carried out during 2008-2010 aiming at increasing out-of-hospital cardiac arrest (OHCA) survival. The intervention included mass media focus on resuscitation and widespread educational activities. The aim of this study was to compare....... There was no significant change in all-rhythm 30-day survival for non-EMS witnessed OHCAs with presumed cardiac aetiology (6.7% [95% CI 3-13] in the follow-up period; vs. 4.6% [95% CI 1-12], p=0.76). CONCLUSION: In a 3-year follow-up period after an intervention engaging laypersons in resuscitation through mass education...... in BLS combined with a media focus on resuscitation, we observed a persistent significant increase in the bystander BLS rate for all OHCAs with presumed cardiac aetiology. There was no significant difference in 30-day survival....

  16. Predictive risk factors for persistent postherniotomy pain

    DEFF Research Database (Denmark)

    Aasvang, Eske K; Gmaehle, Eliza; Hansen, Jeanette B

    2010-01-01

    BACKGROUND: Persistent postherniotomy pain (PPP) affects everyday activities in 5-10% of patients. Identification of predisposing factors may help to identify the risk groups and guide anesthetic or surgical procedures in reducing risk for PPP. METHODS: A prospective study was conducted in 464...... patients undergoing open or laparoscopic transabdominal preperitoneal elective groin hernia repair. Primary outcome was identification of risk factors for substantial pain-related functional impairment at 6 months postoperatively assessed by the validated Activity Assessment Scale (AAS). Data on potential...... risk factors for PPP were collected preoperatively (pain from the groin hernia, preoperative AAS score, pain from other body regions, and psychometric assessment). Pain scores were collected on days 7 and 30 postoperatively. Sensory functions including pain response to tonic heat stimulation were...

  17. Determinants of persistent asthma in young adults

    DEFF Research Database (Denmark)

    Traulsen, Lisbet Krogh; Halling, Anders; Bælum, Jesper

    2018-01-01

    Objective: The aim of the study was to evaluate determinants for the prognosis of asthma in a population-based cohort of young adults. Design: The study was a nine-year clinical follow up of 239 asthmatic subjects from an enriched population-based sample of 1,191 young adults, aged 20-44 years, who...... participated in an interviewer-administered questionnaire and clinical examination at baseline in 2003-2006. From the interview, an asthma score was generated as the simple sum of affirmative answers to five main asthma-like symptoms in order to analyse symptoms of asthma as a continuum. The clinical...... examination comprised spirometry, bronchial challenge or bronchodilation, and skin prick test. Results: Among the 239 individuals with asthma at baseline 164 (69%) had persistent asthma at follow up, while 68 (28%) achieved remission of asthma and seven (3%) were diagnosed with COPD solely. Determinants...

  18. Uranium occurrences and exploration experience in India

    International Nuclear Information System (INIS)

    Chaki, A.

    2010-01-01

    As per the Indian Government laws, minerals containing uranium are classified as strategic and uranium exploration and mining is an exclusive subject of the Central Government. Exploration for atomic minerals began in India in the year 1949 and, over a period of sixty years, India has created a large pool of uranium scientists and, at present, more than 500 scientists are employed by the Government of India for exploration of atomic minerals in India. In line with other countries, India's efforts in the 1960s, 1970s and 1980s were focused in the exploration for vein-type mineralization and succeeded in the discovery in three provinces, viz. Singhbhum Shear Zone (SSZ), Jharkhand; Umra, Rajasthan and Lesser Himalayas of Uttarakhand and Himachal Pradesh. Of these, the SSZ has emerged as a major uranium province with 17 low-grade, low- to medium-tonnage deposits. Presently, the only uranium producing mines are situated in this province. Simultaneously, many uranium occurrences and deposits of QPC, vein and metasomatite types, essentially of low grade, low tonnage, were located all over the country. In the early eighties, the Cretaceous Mahadek basin in the northeastern state of Meghalaya was recognized as a potential province for sandstone-type uranium mineralization and, within a span of fifteen years, five low- to medium-grade, low-tonnage deposits were established. The 180-km long belt of Cretaceous fluviatile felspathic sandstones along the southern fringe of Shillong plateau below a moderate cover of tertiary sediments holds potential for more resources. Ground and airborne geophysical techniques are being looked at to provide vital clues on depositional controls for future sub-surface exploration. In the mean time, a major uranium province in the southern part of Proterozoic Cuddapah basin was discovered, where uranium mineralization is hosted in dolomitic limestone. The mineralization is stratabound and occurs intermittently over a strike length of nearly 160 km

  19. Occurrence of genus Monostroma (Ulvales, Chlorophyta) from Ratnagiri (Maharashtra)

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A; Agadi, V.V.; Dhargalkar, V.K.

    The occurrence of a genus Monostroma has been recorded from the Shirgaon creek at Ratnagiri along the central west coast of India. The Monostroma sp. was found in the brackish water environment with low salinity, high nutrients and thick mangrove...

  20. Rare occurrence of the left maxillary horizontal third molar impaction ...

    African Journals Online (AJOL)

    Rare occurrence of the left maxillary horizontal third molar impaction, the right maxillary third molar vertical impaction and the left mandibular third molar vertical impaction with inferior alveolar nerve proximity in a 30 year old female: a case report.

  1. Scandium: its occurrence, chemistry, physics, metallurgy, biology, and technology

    International Nuclear Information System (INIS)

    Horovitz, C.T.

    1975-01-01

    This book describes the following aspects of scandium: discovery and history, occurrence in nature, geochemistry and mineralogy, chemical, physical and technological properties, fabrication and metallurgy, its biological significance and toxicology, and its uses. (Extensive references for each chapter)

  2. Heavy mineral occurrence off Hazira, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Vora, K.H.; Mislankar, P.G.; Gujar, A.R.

    The occurrence of heavy mineral placers on the west coast of India are well known from Konkan and Malabar Coast. However, a geological and geophysical investigation (including echosounding and side scan sonar profiles and 7 samples) off Hazira...

  3. Report to Congress on abnormal occurrences, April--June 1992

    International Nuclear Information System (INIS)

    1992-09-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from April 1 through June 30, 1992. Five abnormal occurrences are discussed in this report. One involved an extended loss of high-head safety injection capability at the Shearon Harris Nuclear Power Plant. The other four involved medical misadministrations (three therapeutic and one diagnostic) at NRC-licensed facilities. No abnormal occurrences were reported by NRC's Agreement States. The report also contains information updating a previously reported abnormal occurrence

  4. Occurrence of helically coiled microfossil Obruchevella in the Owk ...

    Indian Academy of Sciences (India)

    In the Owk Shale, four species of Obruchevella, viz., O. delicata, O. parva, O. minor and O. .... Asterisk indicate the level of the occurrence of carbonaceous fossils. (c) Locality ...... A B (Moscow: Nauka), English translation published in. 1990 ...

  5. Method Development, Monitoring, and Occurrence of Microcystins in Ambient Water

    Science.gov (United States)

    The occurrence and intensity of cyanobacterial harmful blooms have become increasingly common over the last few decades. Cyanobacteria are a worldwide concern in areas with eutrophic water conditions. Cyanotoxins generated from cyanobacteria are harmful ecologically, cause econom...

  6. Occurrence of Porphyra vietnamensis (Bangiales, Rhodophyta) along the Goa coast

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.; Agadi, V.V.; Untawale, A.G.

    The occurrence of a red alga, Porphyra vietnamensis has been studied along the Goa Coast (west coast of India). The growth period was observed during the monsoon (July-October) and optimum growth was recorded during August, when temperature...

  7. Some attributes of snow occurrence and snowmelt/sublimation rates ...

    African Journals Online (AJOL)

    Some attributes of snow occurrence and snowmelt/sublimation rates in the Lesotho ... and trimmed MODIS SNOMAP image using the ArcGIS Spatial Analyst tool. ... and hydrology, earth surface processes, and rural livelihoods in the Lesotho ...

  8. General characterization of the uranium occurrence in the formation Esperanza

    International Nuclear Information System (INIS)

    Olivera, J.; Sanchez, J.; Alcalde, J.; Pena, B.; Geler, T.

    1995-01-01

    The main geological, geophysical (Radiometric survey, gamma spectrometric survey, measurement of Rn 222), geochemical and mineralogical characteristics in uranium occurrences, located in the Esperanza formation in Pinar del Rio, Cuba are showed

  9. Occurrence of thraustochytrid fungi in corals and coral mucus

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, S.; Balasubramanian

    Occurrence of thraustochytrid fungi in corals, fresh coral mucus and floating and attached mucus detritus from the Lakshadweep Islands in the Arabian Sea was studied. Corallochytrium limacisporum Raghukumar, Thraustochytrium motivum Goldstein...

  10. The global compendium of Aedes aegypti and Ae. albopictus occurrence

    Science.gov (United States)

    Kraemer, Moritz U. G.; Sinka, Marianne E.; Duda, Kirsten A.; Mylne, Adrian; Shearer, Freya M.; Brady, Oliver J.; Messina, Jane P.; Barker, Christopher M.; Moore, Chester G.; Carvalho, Roberta G.; Coelho, Giovanini E.; van Bortel, Wim; Hendrickx, Guy; Schaffner, Francis; Wint, G. R. William; Elyazar, Iqbal R. F.; Teng, Hwa-Jen; Hay, Simon I.

    2015-07-01

    Aedes aegypti and Ae. albopictus are the main vectors transmitting dengue and chikungunya viruses. Despite being pathogens of global public health importance, knowledge of their vectors’ global distribution remains patchy and sparse. A global geographic database of known occurrences of Ae. aegypti and Ae. albopictus between 1960 and 2014 was compiled. Herein we present the database, which comprises occurrence data linked to point or polygon locations, derived from peer-reviewed literature and unpublished studies including national entomological surveys and expert networks. We describe all data collection processes, as well as geo-positioning methods, database management and quality-control procedures. This is the first comprehensive global database of Ae. aegypti and Ae. albopictus occurrence, consisting of 19,930 and 22,137 geo-positioned occurrence records respectively. Both datasets can be used for a variety of mapping and spatial analyses of the vectors and, by inference, the diseases they transmit.

  11. Report to Congress on abnormal occurrences, October-December 1987

    International Nuclear Information System (INIS)

    1988-03-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from October 1 to December 31, 1987. The report states that for this reporting period, these was one abnormal occurrence at the NRC licensees; the item involved the suspension of license of an oil and gas well tracer company for noncompliance with NRC regulatory requirements. There were no abnormal occurrences report by the Agreement States. The report also contains information updating some previously reported abnormal occurrences

  12. Report to Congress on abnormal occurrences, July--September 1991

    International Nuclear Information System (INIS)

    1991-12-01

    Section 108 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health and safety and requires a quarterly report of such events to be made to Congress. This report covers the period July through September 1991. The report discusses two abnormal occurrences at NRC-licensed facilities, neither involving a nuclear power plant. One involved radiation exposures to members of the public from a lost radioactive source and the other involved a medical diagnostic midadministration. The Agreement States reported no abnormal occurrences. The report also contains information that updates some previously reported abnormal occurrences

  13. Differences in body composition and occurrence of postural ...

    African Journals Online (AJOL)

    Differences in body composition and occurrence of postural deviations in boys from two ... African Journal for Physical Activity and Health Sciences ... procedures of the International Society for the Advancement of Kinanthropometry (ISAK).

  14. Nitrification in Chloraminated Drinking Water Distribution Systems - Occurrence

    Science.gov (United States)

    This chapter discusses available information on nitrification occurrence in drinking water chloraminated distribution systems. Chapter 4 provides an introduction to causes and controls for nitrification in chloraminated drinking water systems. Both chapters are intended to serve ...

  15. Report to Congress on abnormal occurrences, January-March 1983

    International Nuclear Information System (INIS)

    1983-09-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from January 1 to March 31, 1983. The report states that for this report period, there were three abnormal occurrences at the nuclear power plants licensed by the NRC to operate. The first involved a main feedwater line break due to water hammer. The second involved management and procedural control deficiencies. The third involved failure of the automatic reactor trip system. There were no abnormal occurrences for the other NRC licensees. There were six abnormal occurrences at Agreement State licensees. One involved an individual who ingested and was contaminated by radioactive material. Four involved lost or stolen radioactive sources. One involved radioactive contamination of a metals production facility

  16. the occurrence of post partum anoestrus in bonsmara cows

    African Journals Online (AJOL)

    duration of post partum anoestrus than gain in body mass. Post pactum ... and Bos Taurus cattle to improve fertility and milk pro- duction in high .... The occurrence of post partum anoestrus in beef cows under ranching conditions. Proc.

  17. Occurrence and recalcitrance of polyethylene bag waste in Nigerian ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-13

    Sep 13, 2010 ... Full Length Research Paper. Occurrence and ... by this product as microbial degradation proved ineffective. ... chemically synthesized organic compounds, most of ... have strong ability to resist toxic substances, including.

  18. Sinkhole occurrence in consequence of heavy rainstorms

    Science.gov (United States)

    Parise, Mario; Pisano, Luca; Vennari, Carmela

    2016-04-01

    hazards. References Ford, D.C. & Williams P.W. (2007). Karst geomorphology and hydrology. 2nd ed. John Wiley & Sons, Chichester, U.K. Gutierrez, F., J. Guerrero J. & Lucha P. (2008) A genetic classification of sinkholes illustrated from evaporite paleo-karst exposures in Spain. Environmental Geology, 53, 993-1006. Gutierrez F., Parise M., De Waele J. & Jourde H. (2014) A review on natural and human-induced geohazards and impacts in karst. Earth-Science Reviews, 138, 61-88. Martinotti M.E., Pisano L., Trabace M., Marchesini I., Peruccacci S., Rossi M., Amoruso G., Loiacono P., Vennari C., Vessia G., Parise M. & Brunetti M. (2015) Extreme rainfall events in karst environments: the case study of September 2014 in the Gargano area (southern Italy). Geophysical Research Abstracts, 17, 2683. Parise M. (2008) Rock failures in karst. In: Cheng Z., Zhang J., Li Z., Wu F. & Ho K. (Eds.), Landslides and Engineered Slopes. Proc. 10th International Symposium on Landslides, Xi'an (China), June 30 - July 4, 2008, 1, 275-280. Parise M. (2012) A present risk from past activities: sinkhole occurrence above underground quarries. Carbonates and Evaporites, 27 (2), 109-118. Parise M. (2015a) A procedure for evaluating the susceptibility to natural and anthropogenic sinkholes. Georisk, 9 (4), 272-285. Parise M. (2015b) Karst geo-hazards: causal factors, human actions, and management issues. Acta Carsologica, 44 (2). Parise M. & Vennari C. (2013) A chronological catalogue of sinkholes in Italy: the first step toward a real evaluation of the sinkhole hazard. In: Land L., Doctor D.H. & Stephenson B. (Eds.), Proceedings of the 13th Multidisciplinary Conference on Sinkholes and the Engineering and Environmental Impacts of Karst, Carlsbad (New Mexico, USA), 6-10 May 2013, National Cave and Karst Research Institute, 383-392. Parise M., Ravbar N., Živanovic V., Mikszewski A., Kresic N., Madl-Szonyi J. & Kukuric N. (2015) Hazards in Karst and Managing Water Resources Quality. Chapter 17 in: Z

  19. Occurrence and removal of estrogens in Brazilian wastewater treatment plants

    International Nuclear Information System (INIS)

    Pessoa, Germana P.; Souza, Neyliane C. de; Vidal, Carla B.; Alves, Joana A.C.; Firmino, Paulo Igor M.; Nascimento, Ronaldo F.; Santos, André B. dos

    2014-01-01

    This paper evaluated the occurrence and removal efficiency of four estrogenic hormones in five biological wastewater treatment plants (WWTPs), located in the State of Ceará, Brazil. The five WWTPs comprised: two systems consisted of one facultative pond followed by two maturation ponds, one facultative pond, one activated sludge (AS) system followed by a chlorination step, and one upflow anaerobic sludge blanket (UASB) reactor followed by a chlorination step. Estrogen occurrence showed a wide variation among the analyzed influent and effluent samples. Estrone (E1) showed the highest occurrence in the influent (76%), whereas both 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) presented a 52% occurrence, and the compound 17β-estradiol 17-acetate (E2-17A), a 32% one. The occurrence in the effluent samples was 48% for E1, 28% for E2, 12% for E2-17A, and 40% for EE2. The highest concentrations of E1 and EE2 hormones in the influent were 3050 and 3180 ng L −1 , respectively, whereas E2 and E2-17A had maximum concentrations of 776 and 2300 ng L −1 , respectively. The lowest efficiencies for the removal of estrogenic hormones were found in WWTP consisted of waste stabilization ponds, ranging from 54 to 79.9%. The high-rate systems (AS and UASB), which have chlorination as post-treatment, presented removal efficiencies of approximately 95%. - Highlights: • The occurrence of four endocrine disrupting chemicals was evaluated. • The removal efficiency of four hormones in low-cost plants was examined. • Estrogen occurrence showed a wide variation in influent and effluent samples. • Estrone showed the highest occurrence in the influent and the effluent samples. • WSP treatment was observed to be less effective for removing estrogens

  20. Predicted occurrence rate of severe transportation accidents involving large casks

    International Nuclear Information System (INIS)

    Dennis, A.W.

    1978-01-01

    A summary of the results of an investigation of the severities of highway and railroad accidents as they relate to the shipment of large radioactive materials casks is discussed. The accident environments considered are fire, impact, crash, immersion, and puncture. For each of these environments, the accident severities and their predicted frequencies of occurrence are presented. These accident environments are presented in tabular and graphic form to allow the reader to evaluate the probabilities of occurrence of the accident parameter severities he selects

  1. Problems involved in calculating the probability of rare occurrences

    International Nuclear Information System (INIS)

    Tittes, E.

    1986-01-01

    Also with regard to the characteristics such as occurrence probability or occurrence rate, there are limits which have to be observed, or else probability data and thus the concept of determinable risk itself will lose its practical value. The mathematical models applied for probability assessment are based on data supplied by the insurance companies, reliability experts in the automobile industry, or by planning experts in the field of traffic or information supply. (DG) [de

  2. Occurrence and removal of estrogens in Brazilian wastewater treatment plants

    Energy Technology Data Exchange (ETDEWEB)

    Pessoa, Germana P. [Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bl. 713, CEP: 60455-900, Fortaleza, CE (Brazil); Souza, Neyliane C. de [Department Sanitary and Environmental Engineering, State University of Paraíba, Rua Juvêncio Arruda, S/N, Campus Universitário, Bodocongó, CEP: 58109-790, Campina Grande, PB (Brazil); Vidal, Carla B.; Alves, Joana A.C.; Firmino, Paulo Igor M. [Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bl. 713, CEP: 60455-900, Fortaleza, CE (Brazil); Nascimento, Ronaldo F. [Department of Analytical Chemistry and Physical Chemistry, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bl. 940, CEP: 60451-970, Fortaleza, CE (Brazil); Santos, André B. dos, E-mail: andre23@ufc.br [Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bl. 713, CEP: 60455-900, Fortaleza, CE (Brazil)

    2014-08-15

    This paper evaluated the occurrence and removal efficiency of four estrogenic hormones in five biological wastewater treatment plants (WWTPs), located in the State of Ceará, Brazil. The five WWTPs comprised: two systems consisted of one facultative pond followed by two maturation ponds, one facultative pond, one activated sludge (AS) system followed by a chlorination step, and one upflow anaerobic sludge blanket (UASB) reactor followed by a chlorination step. Estrogen occurrence showed a wide variation among the analyzed influent and effluent samples. Estrone (E1) showed the highest occurrence in the influent (76%), whereas both 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) presented a 52% occurrence, and the compound 17β-estradiol 17-acetate (E2-17A), a 32% one. The occurrence in the effluent samples was 48% for E1, 28% for E2, 12% for E2-17A, and 40% for EE2. The highest concentrations of E1 and EE2 hormones in the influent were 3050 and 3180 ng L{sup −1}, respectively, whereas E2 and E2-17A had maximum concentrations of 776 and 2300 ng L{sup −1}, respectively. The lowest efficiencies for the removal of estrogenic hormones were found in WWTP consisted of waste stabilization ponds, ranging from 54 to 79.9%. The high-rate systems (AS and UASB), which have chlorination as post-treatment, presented removal efficiencies of approximately 95%. - Highlights: • The occurrence of four endocrine disrupting chemicals was evaluated. • The removal efficiency of four hormones in low-cost plants was examined. • Estrogen occurrence showed a wide variation in influent and effluent samples. • Estrone showed the highest occurrence in the influent and the effluent samples. • WSP treatment was observed to be less effective for removing estrogens.

  3. Identification of Chinese medicine syndromes in persistent insomnia associated with major depressive disorder: a latent tree analysis.

    Science.gov (United States)

    Yeung, Wing-Fai; Chung, Ka-Fai; Zhang, Nevin Lian-Wen; Zhang, Shi Ping; Yung, Kam-Ping; Chen, Pei-Xian; Ho, Yan-Yee

    2016-01-01

    Chinese medicine (CM) syndrome (zheng) differentiation is based on the co-occurrence of CM manifestation profiles, such as signs and symptoms, and pulse and tongue features. Insomnia is a symptom that frequently occurs in major depressive disorder despite adequate antidepressant treatment. This study aims to identify co-occurrence patterns in participants with persistent insomnia and major depressive disorder from clinical feature data using latent tree analysis, and to compare the latent variables with relevant CM syndromes. One hundred and forty-two participants with persistent insomnia and a history of major depressive disorder completed a standardized checklist (the Chinese Medicine Insomnia Symptom Checklist) specially developed for CM syndrome classification of insomnia. The checklist covers symptoms and signs, including tongue and pulse features. The clinical features assessed by the checklist were analyzed using Lantern software. CM practitioners with relevant experience compared the clinical feature variables under each latent variable with reference to relevant CM syndromes, based on a previous review of CM syndromes. The symptom data were analyzed to build the latent tree model and the model with the highest Bayes information criterion score was regarded as the best model. This model contained 18 latent variables, each of which divided participants into two clusters. Six clusters represented more than 50 % of the sample. The clinical feature co-occurrence patterns of these six clusters were interpreted as the CM syndromes Liver qi stagnation transforming into fire, Liver fire flaming upward, Stomach disharmony, Hyperactivity of fire due to yin deficiency, Heart-kidney noninteraction, and Qi deficiency of the heart and gallbladder. The clinical feature variables that contributed significant cumulative information coverage (at least 95 %) were identified. Latent tree model analysis on a sample of depressed participants with insomnia revealed 13 clinical

  4. Report to Congress on abnormal occurrences, January--March 1978

    International Nuclear Information System (INIS)

    1978-01-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. The report, the twelfth in the series, covers the period from January 1 to March 31, 1978. The following incidents or events in that time period were determined by the Commission to be significant and reportable: (1) There was one abnormal occurrence at the 68 nuclear power plants licensed to operate. The event involved insulation failures in containment electrical penetrations. (2) There were no abnormal occurrences at fuel cycle facilities (other than nuclear power plants). (3) There were no abnormal occurrences at other license facilities. (4) There was one abnormal occurrence reported by an Agreement State Licensee. The event involved an overexposure of a radiographer. The report also contains information updating previously reported abnormal occurrences

  5. Report to Congress on abnormal occurrences, July--September 1989

    International Nuclear Information System (INIS)

    1990-01-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report covers the period from July 1 to September 30, 1989. For this reporting period, there were five abnormal occurrences. One abnormal occurrence took place at a licensed nuclear power plant and involved significant deficiencies associated with the containment recirculation sump at the Trojan facility. The other four abnormal occurrences took place under other NRC-issued licenses: the first involved a medical diagnostic misadministration; the second involved a medical therapy misadministration; the third involved a radiation overexposure of a radiographer; and the fourth involved a significant breakdown and careless disregard of the radiation safety program at three of a licensee's manufacturing facilities. The Agreement States reported no abnormal occurrences during the reporting period. The report also contains information that updates some previously reported abnormal occurrences. 17 refs

  6. Report to Congress on abnormal occurrences, April--June 1978

    International Nuclear Information System (INIS)

    1978-01-01

    Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event which the Nuclear Regulatory Commission determines to be significant from the standpoint of public health or safety and requires a quarterly report of such events to be made to Congress. This report, the thirteenth in the series, covers the period from April 1 to June 30, 1978. The following incidents or events in that period were determined by the Commission to be significant and reportable: (1) There were two abnormal occurrences at the 69 nuclear power plants licensed to operate. One involved a generic concern pertaining to fuel assembly control rod guide tube integrity. The second involved an overexposure of two radiation protection technicians. (2) There were no abnormal occurrences at fuel cycle facilities (other than nuclear power plants). (3) There were no abnormal occurrences at other licensee facilities. (4) There was one abnormal occurrence reported by an agreement state. The event involved willful violations of regulations and subsequent termination of a license. This report also contains information updating previously reported abnormal occurrences

  7. Biofilm formation and phenotypic variation enhance predation-driven persistence of Vibrio cholerae

    DEFF Research Database (Denmark)

    Matz, Carsten; McDougald, D.; Moreno, A.M.

    2005-01-01

    Persistence of the opportunistic bacterial pathogen Vibrio cholerae in aquatic environments is the principal cause for seasonal occurrence of cholera epidemics. This causality has been explained by postulating that V. cholerae forms biofilms in association with animate and inanimate surfaces....... Alternatively, it has been proposed that bacterial pathogens are an integral part of the natural microbial food web and thus their survival is constrained by protozoan predation. Here, we report that both explanations are interrelated. our data show that biofilms are the protective agent enabling V. cholerae...... to survive protozoan grazing while their planktonic counterparts are eliminated. Grazing on planktonic V. cholerae was found to select for the biofilm-enhancing rugose phase variant, which is adapted to the surf ace-associated niche by the production of exopolymers. Interestingly, grazing resistance in V...

  8. Inflation persistence in African countries: Does inflation targeting matter?

    OpenAIRE

    Phiri, Andrew

    2016-01-01

    This study investigates inflation persistence in annual CPI inflation collected between 1994 and 2014 for 46 African countries. We group these countries into panels according to whether they are inflation targeters or not and conduct estimations for pre and post inflation targeting periods. Interestingly enough, we find that inflation persistence was much higher for inflation targeters in periods before adopting their inflation targeting regimes and inflation persistence dropped by 40 percent...

  9. Factors associated with the occurrence of Triatoma sordida (Hemiptera: Reduviidae in rural localities of Central-West Brazil

    Directory of Open Access Journals (Sweden)

    Juliana Chedid Nogared Rossi

    2015-04-01

    Full Text Available This study estimates the factors of artificial environments (houses and peridomestic areas associated with Triatoma sordida occurrence. Manual searches for triatomines were performed in 136 domiciliary units (DUs in two rural localities of Central-West Brazil. For each DU, 32 structural, 23 biotic and 28 management variables were obtained. Multiple logistic regression analysis was performed in order to identify statistically significant variables associated with occurrence of T. sordida in the study areas. A total of 1,057 specimens (99% in peridomiciles, mainly chicken coops of T. sordida were collected from 63 DUs (infestation: 47%; density: ~8 specimens/DU; crowding: ~17 specimens/infested DU; colonisation: 81%. Only six (0.6% out of 945 specimens examined were infected with Trypanosoma cruzi. The final adjusted logistic regression model indicated that the probability of T. sordida occurrence was higher in DU with wooden chicken coops, presence of > 30 animals in wooden corrals, presence of wood piles and presence of food storeroom. The results show the persistence of T. sordida in peridomestic habitats in rural localities of Central-West Brazil. However, the observed low intradomestic colonisation and minimal triatomine infection rates indicate that T. sordida has low potential to sustain high rates of T. cruzi transmission to residents of these localities.

  10. The modality effect and echoic persistence.

    Science.gov (United States)

    Watkins, O C; Watkins, M J

    1980-09-01

    a 20-sec silent copying task interpolated before free recall reduced visual recency more than auditory recency, and so enhanced the modality effect. This suggests that, contrary to prevailing opinion, the modality effect in delayed recall is not the result of a memory that is modality-independent. In Experiment 6 a modality effect found with serial recall after an unfilled interval of 18 sec was unaffected by visual distractor task, but almost eliminated by an auditory distractor task, given just prior to recall. It thus seems that the modality effect in delayed recall is the result of information persisting in echoic form until recall. It is concluded that echoic information can persist for many seconds and is used directly at the time of recall.

  11. Degassing Processes at Persistently Active Explosive Volcanoes

    Science.gov (United States)

    Smekens, Jean-Francois

    Among volcanic gases, sulfur dioxide (SO2) is by far the most commonly measured. More than a monitoring proxy for volcanic degassing, SO 2 has the potential to alter climate patterns. Persistently active explosive volcanoes are characterized by short explosive bursts, which often occur at periodic intervals numerous times per day, spanning years to decades. SO 2 emissions at those volcanoes are poorly constrained, in large part because the current satellite monitoring techniques are unable to detect or quantify plumes of low concentration in the troposphere. Eruption plumes also often show high concentrations of ash and/or aerosols, which further inhibit the detection methods. In this work I focus on quantifying volcanic gas emissions at persistently active explosive volcanoes and their variations over short timescales (minutes to hours), in order to document their contribution to natural SO2 flux as well as investigate the physical processes that control their behavior. In order to make these measurements, I first develop and assemble a UV ground-based instrument, and validate it against an independently measured source of SO2 at a coal-burning power plant in Arizona. I establish a measurement protocol and demonstrate that the instrument measures SO 2 fluxes with Indonesia), a volcano that has been producing cycles of repeated explosions with periods of minutes to hours for the past several decades. Semeru produces an average of 21-71 tons of SO2 per day, amounting to a yearly output of 8-26 Mt. Using the Semeru data, along with a 1-D transient numerical model of magma ascent, I test the validity of a model in which a viscous plug at the top of the conduit produces cycles of eruption and gas release. I find that it can be a valid hypothesis to explain the observed patterns of degassing at Semeru. Periodic behavior in such a system occurs for a very narrow range of conditions, for which the mass balance between magma flux and open-system gas escape repeatedly

  12. HIV Persistence in Adipose Tissue Reservoirs.

    Science.gov (United States)

    Couturier, Jacob; Lewis, Dorothy E

    2018-02-01

    The purpose of this review is to examine the evidence describing adipose tissue as a reservoir for HIV-1 and how this often expansive anatomic compartment contributes to HIV persistence. Memory CD4 T cells and macrophages, the major host cells for HIV, accumulate in adipose tissue during HIV/SIV infection of humans and rhesus macaques. Whereas HIV and SIV proviral DNA is detectable in CD4 T cells of multiple fat depots in virtually all infected humans and monkeys examined, viral RNA is less frequently detected, and infected macrophages may be less prevalent in adipose tissue. However, based on viral outgrowth assays, adipose-resident CD4 T cells are latently infected with virus that is replication-competent and infectious. Additionally, adipocytes interact with CD4 T cells and macrophages to promote immune cell activation and inflammation which may be supportive for HIV persistence. Antiviral effector cells, such as CD8 T cells and NK/NKT cells, are abundant in adipose tissue during HIV/SIV infection and typically exceed CD4 T cells, whereas B cells are largely absent from adipose tissue of humans and monkeys. Additionally, CD8 T cells in adipose tissue of HIV patients are activated and have a late differentiated phenotype, with unique TCR clonotypes of less diversity relative to blood CD8 T cells. With respect to the distribution of antiretroviral drugs in adipose tissue, data is limited, but there may be class-specific penetration of fat depots. The trafficking of infected immune cells within adipose tissues is a common event during HIV/SIV infection of humans and monkeys, but the virus may be mostly transcriptionally dormant. Viral replication may occur less in adipose tissue compared to other major reservoirs, such as lymphoid tissue, but replication competence and infectiousness of adipose latent virus are comparable to other tissues. Due to the ubiquitous nature of adipose tissue, inflammatory interactions among adipocytes and CD4 T cells and macrophages, and

  13. Quantification of image persistence in a digital angiography system

    International Nuclear Information System (INIS)

    Okkalides, D.P.; Raptou, P.D.

    1993-01-01

    Image persistence, as a characteristic of video imaging systems affecting the quality of fast moving fluoroscopic images, is shown to vary considerably. A simple quantitative method for measuring image persistence in a digital angiography system is presented, together with a series of image intensifier exposure-response curves. For the Saticon tube, used with the Siemens 3VA Digitron, it was found that persistence increased for low exposure rates and may increase to 31% at a 120 ms interval. In addition, a sharp increase in image persistence, from 8.3% to 33%, was observed within 18 months from installation of the system. (author)

  14. Packaging- and transportation-related occurrence reports: 1993 annual report

    International Nuclear Information System (INIS)

    Welch, M.J.; Dickerson, L.S.; Jennings, S.D.

    1994-06-01

    The US Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS) is an interactive computer system designed to support DOE-owned or -operated facilities in reporting and processing of information concerning occurrences related to facility operations. The requirements for reporting and the extent of the occurrences to be reported are defined in DOE Order 5000.3B, Occurrence Reporting and Processing of Operations Information (hereafter referred to as DOE 5000.3B). The centralized data base, which is managed by the Idaho National Engineering Laboratory (INEL), provides computerized support for the collection, distribution, updating, analysis, and sign-off of information in the occurrence reports (ORs). The Oak Ridge National Laboratory (ORNL) Packaging and Transportation Safety (PATS) Program has been made responsible for retrieving reports and information pertaining to transportation and packaging incidents/accidents from the centralized ORPS data base. This annual report details the methodology that PATS uses to conduct searches of the ORPS for pertinent information, the form of the reporting to EH-332, review and examination of trends observed in ORs related to transportation and packaging safety, a presentation and discussion of the root-cause codes of ORPS and the nature of occurrence codes of PATS, timely processing of notification reports to final stage, and analysis of 10% of the reported ORs that were finalized to determine whether the actions taken to close out the occurrences were sufficient to ensure remediation of the incident and to prevent a recurrence. Data in the report are presented by calendar years

  15. SCORPION II persistent surveillance system update

    Science.gov (United States)

    Coster, Michael; Chambers, Jon

    2010-04-01

    This paper updates the improvements and benefits demonstrated in the next generation Northrop Grumman SCORPION II family of persistent surveillance and target recognition systems produced by the Xetron Campus in Cincinnati, Ohio. SCORPION II reduces the size, weight, and cost of all SCORPION components in a flexible, field programmable system that is easier to conceal and enables integration of over fifty different Unattended Ground Sensor (UGS) and camera types from a variety of manufacturers, with a modular approach to supporting multiple Line of Sight (LOS) and Beyond Line of Sight (BLOS) communications interfaces. Since 1998 Northrop Grumman has been integrating best in class sensors with its proven universal modular Gateway to provide encrypted data exfiltration to Common Operational Picture (COP) systems and remote sensor command and control. In addition to feeding COP systems, SCORPION and SCORPION II data can be directly processed using a common sensor status graphical user interface (GUI) that allows for viewing and analysis of images and sensor data from up to seven hundred SCORPION system gateways on single or multiple displays. This GUI enables a large amount of sensor data and imagery to be used for actionable intelligence as well as remote sensor command and control by a minimum number of analysts.

  16. Persistent Scatterer Interferometry using Sentinel-1 Data

    Science.gov (United States)

    Monserrat, Oriol; Crosetto, Michele; Devanthery, Nuria; Cuevas-Gonzalez, Maria; Qihuan, Huang; Barra, Anna; Crippa, Bruno

    2016-04-01

    This work will be focused on the deformation measurement and monitoring using SAR imagery from the C-band Sentinel-1, a space mission funded by the European Union and carried out by the European Space Agency (ESA) within the Copernicus Programme. The work will firstly address the data processing and analysis procedure implemented by the authors. This includes both Persistent Scatterer Interferometry (PSI) tools to analyse large stacks of SAR images (say, typically more than 20 images), and Differential SAR Interferometry (DInSAR) tools to analyse short SAR image stacks. The work will discuss the characteristics of the main products derived by using Sentinel-1 DInSAR and PSI: deformation maps, deformation velocity maps, deformation time series, residual topographic error, etc. The analysis will be carried out over different types of land use area, e.g. urban, peri-urban and rural areas. The deformation monitoring based on Sentinel-1 data will be compared with the monitoring based on data from pre-existing missions, e.g. C-band ERS and Envisat, X-band TerraSAR-X and CosmoSkyMed, etc. The comparison will concern different study areas, mainly located in Italy and Spain.

  17. Making web annotations persistent over time

    Energy Technology Data Exchange (ETDEWEB)

    Sanderson, Robert [Los Alamos National Laboratory; Van De Sompel, Herbert [Los Alamos National Laboratory

    2010-01-01

    As Digital Libraries (DL) become more aligned with the web architecture, their functional components need to be fundamentally rethought in terms of URIs and HTTP. Annotation, a core scholarly activity enabled by many DL solutions, exhibits a clearly unacceptable characteristic when existing models are applied to the web: due to the representations of web resources changing over time, an annotation made about a web resource today may no longer be relevant to the representation that is served from that same resource tomorrow. We assume the existence of archived versions of resources, and combine the temporal features of the emerging Open Annotation data model with the capability offered by the Memento framework that allows seamless navigation from the URI of a resource to archived versions of that resource, and arrive at a solution that provides guarantees regarding the persistence of web annotations over time. More specifically, we provide theoretical solutions and proof-of-concept experimental evaluations for two problems: reconstructing an existing annotation so that the correct archived version is displayed for all resources involved in the annotation, and retrieving all annotations that involve a given archived version of a web resource.

  18. Problems persist for French refining sector

    International Nuclear Information System (INIS)

    Beck, R.J.

    1992-01-01

    This paper reports that France's refiners face a continuing shortfall of middle distillate capacity and a persistent surplus of heavy fuel oil. That's the main conclusion of the official Hydrocarbon Directorate's report on how France's refining sector performed in 1991. Imports up---The directorate noted that although net production of refined products in French refineries rose to 1.534 million b/d in 1991 from 1.48 million b/d in 1990, products imports jumped 9.7% to 602,000 b/d in the period. The glut of heavy fuel oil eased to some extent last year because French nuclear power capacity, heavily dependent on ample water supplies, was crimped by drought. That spawned fuel switching. The most note worthy increase in imports was for motor diesel, climbing to 176,000 b/d from 148,000 b/d in 1990. Tax credits are spurring French consumption of that fuel. For the first time, consumption of motor diesel in 1991 outstripped that of gasoline at 374,000 b/d and 356,000 b/d respectively

  19. Persistent hyperplastic primary vitreous: imaging evaluation

    International Nuclear Information System (INIS)

    Jacob, Beatriz Mahmud; Teixeira, Kim-Ir-Sen Santos; Figueiredo, Sizenildo da Silva; Nobrega, Bruno Barcelos da

    2003-01-01

    Persistent hyperplastic primary vitreous (PHPV) is a congenital developmental anomaly of the eye that primarily affects premature infants. PHPV results from failure of regression of the embryogenic primary vitreous and hyaloid vasculature, and proliferation of connective tissue. Three types of PHPV may be found: anterior, posterior and a combination of anterior and posterior. The clinical findings include leukocoria (white pupillary reflex) and microphthalmic eye. This anomaly is usually unilateral and unassociated with other systemic findings. The differential diagnosis between PHPV and other ocular diseases may be difficult due to similar features such as leukocoria, detached retina, retinal folds and cataract. Other diseases with similar features include retinoblastoma, isolated congenital cataract, retinopathy of prematurity and pseudo gliomas or leukocorias. Direct visualization of the remnants of the fetal hyaloid vascular system offers the best evidence of PHPV. However, diagnosis using the ophthalmoscope is sometimes impossible because of opaque tissues. In this circumstance an indirect visualization by ultrasound, computed tomography or magnetic resonance imaging may be useful. These imaging methods provide valuable information for the differentiation from other diseases, particularly retinoblastoma. The authors present a review of the literature and an iconographic study of the imaging findings in patients with PHPV. (author)

  20. Persistent consequences of atypical early number concepts

    Directory of Open Access Journals (Sweden)

    Michèle M. M. Mazzocco

    2013-09-01

    Full Text Available How does symbolic number knowledge performance help identify young children at risk for poor mathematics achievement outcomes? In research and practice, classification of mathematics learning disability (MLD, or dyscalculia is typically based on composite scores from broad measures of mathematics achievement. These scores do predict later math achievement levels, but do not specify the nature of math difficulties likely to emerge among students at greatest risk for long-term mathematics failure. Here we report that gaps in 2nd and 3rd graders’ number knowledge predict specific types of errors made on math assessments at Grade 8. Specifically, we show that early whole number misconceptions predict slower and less accurate performance, and atypical computational errors, on Grade 8 arithmetic tests. We demonstrate that basic number misconceptions can be detected by idiosyncratic responses to number knowledge items, and that when such misconceptions are evident during primary school they persist throughout the school age years, with variable manifestation throughout development. We conclude that including specific qualitative assessments of symbolic number knowledge in primary school may provide greater specificity of the types of difficulties likely to emerge among students at risk for poor mathematics outcomes.