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Sample records for long-term gps tracking

  1. Long-term GPS tracking of ocean sunfish Mola mola offers a new direction in fish monitoring.

    PubMed

    Sims, David W; Queiroz, Nuno; Humphries, Nicolas E; Lima, Fernando P; Hays, Graeme C

    2009-10-09

    Satellite tracking of large pelagic fish provides insights on free-ranging behaviour, distributions and population structuring. Up to now, such fish have been tracked remotely using two principal methods: direct positioning of transmitters by Argos polar-orbiting satellites, and satellite relay of tag-derived light-level data for post hoc track reconstruction. Error fields associated with positions determined by these methods range from hundreds of metres to hundreds of kilometres. However, low spatial accuracy of tracks masks important details, such as foraging patterns. Here we use a fast-acquisition global positioning system (Fastloc GPS) tag with remote data retrieval to track long-term movements, in near real time and position accuracy of <70 m, of the world's largest bony fish, the ocean sunfish Mola mola. Search-like movements occurred over at least three distinct spatial scales. At fine scales, sunfish spent longer in highly localised areas with faster, straighter excursions between them. These 'stopovers' during long-distance movement appear consistent with finding and exploiting food patches. This demonstrates the feasibility of GPS tagging to provide tracks of unparalleled accuracy for monitoring movements of large pelagic fish, and with nearly four times as many locations obtained by the GPS tag than by a conventional Argos transmitter. The results signal the potential of GPS-tagged pelagic fish that surface regularly to be detectors of resource 'hotspots' in the blue ocean and provides a new capability for understanding large pelagic fish behaviour and habitat use that is relevant to ocean management and species conservation.

  2. Long-Term GPS Tracking of Ocean Sunfish Mola mola Offers a New Direction in Fish Monitoring

    PubMed Central

    Sims, David W.; Queiroz, Nuno; Humphries, Nicolas E.; Lima, Fernando P.; Hays, Graeme C.

    2009-01-01

    Satellite tracking of large pelagic fish provides insights on free-ranging behaviour, distributions and population structuring. Up to now, such fish have been tracked remotely using two principal methods: direct positioning of transmitters by Argos polar-orbiting satellites, and satellite relay of tag-derived light-level data for post hoc track reconstruction. Error fields associated with positions determined by these methods range from hundreds of metres to hundreds of kilometres. However, low spatial accuracy of tracks masks important details, such as foraging patterns. Here we use a fast-acquisition global positioning system (Fastloc GPS) tag with remote data retrieval to track long-term movements, in near real time and position accuracy of <70 m, of the world's largest bony fish, the ocean sunfish Mola mola. Search-like movements occurred over at least three distinct spatial scales. At fine scales, sunfish spent longer in highly localised areas with faster, straighter excursions between them. These ‘stopovers’ during long-distance movement appear consistent with finding and exploiting food patches. This demonstrates the feasibility of GPS tagging to provide tracks of unparalleled accuracy for monitoring movements of large pelagic fish, and with nearly four times as many locations obtained by the GPS tag than by a conventional Argos transmitter. The results signal the potential of GPS-tagged pelagic fish that surface regularly to be detectors of resource ‘hotspots’ in the blue ocean and provides a new capability for understanding large pelagic fish behaviour and habitat use that is relevant to ocean management and species conservation. PMID:19816576

  3. Long-term visual tracking based on correlation filters

    NASA Astrophysics Data System (ADS)

    Wei, Quanlu; Lao, Songyang; Bai, Liang

    2017-03-01

    In order to accomplish the long term visual tracking task in complex scenes, solve problems of scale variation, appearance variation and tracking failure, a long term tracking algorithm is given based on the framework of collaborative correlation tracking. Firstly, we integrate several powerful features to boost the represent ability based on the kernel correlation filter, and extend the filter by embedding a scale factor into the kernelized matrix to handle the scale variation. Then, we use the Peak-Sidelobe Ratio to decide whether the object is tracked successfully, and a CUR filter for re-detection the object in case of tracking failure is learnt with random sampling. Corresponding experiment is performed on 17 challenging benchmark video sequences. Compared with the 8 existing state-of-the-art algorithms based on discriminative learning method, the results show that the proposed algorithm improves the tracking performance on several indexes, and is robust to complex scenes for long term visual tracking.

  4. Fast and long term lipid droplet tracking with CARS microscopy.

    PubMed

    Jüngst, Christian; Winterhalder, Martin J; Zumbusch, Andreas

    2011-06-01

    Photobleaching of organic fluorophores commonly used in fluorescence microscopy puts a limit to the number of images which can be acquired. Label-free imaging techniques therefore offer advantages both for rapid image acquisition and for long-term observations. CARS microscopy is a label-free imaging technique offering molecule specific contrast. Here we demonstrate that CARS microscopy allows video-rate tracking of intracellular transport of lipid droplets, but also continuous long-term observation of cells over several hours.

  5. GPS Climatology: Long-term PWV Records from a Dense GPS Array (Invited)

    NASA Astrophysics Data System (ADS)

    Heki, K.; Yoshida, K.

    2009-12-01

    More than ten years has passed since people recognized meteorological value of atmospheric delays observed by Global Positioning System (GPS) together with station coordinates. Precipitable water vapor (PWV) data are obtained from ~1000 receivers of GPS Earth Observation Network (GEONET) in Japan in near real time. After years of basic studies of GPS meteorology, Japan Meteorological Agency has recently started to incorporate GPS-PWV routinely into its atmospheric model for numerical weather prediction. Here we expand the concept and study longer term behaviors of the atmospheric water vapor, i.e. GPS climatology. We use zenith total delays (ZTD) at GPS stations over the last 12 years. We also use surface meteorological data from ~200 observatories to isolate delays due to water vapor (zenith wet delay, ZWD) by removing those by dry air (hydrostatic delay). ZWD is proportional to PWV, and we explore climatological signals in PWV, e.g. interannual changes due to El Nino/Southern Oscillation (ENSO), longer-term changes such as North Atlantic Oscillation (NAO), Pacific Decadal Oscillation (PDO), and secular increase due to global warming. Average temperature over Japan in this period shows relatively rapid increase in late 1990’s and 2000’s and moderate decrease in the first half of 2000’s. PWV showed similar long-term signals to the surface temperature changes as well as strong seasonal signatures. These changes negatively correlate with indices of PDO, an inter-decadal climate oscillation in the northern Pacific Ocean bringing colder climates in its western part during positive phases. Unlike surface temperature, PWV did not show significant net increase during the studied period. NAO is considered to be a part of Arctic Oscillation (AO), and strongly influence winter climate in northern Japan. Negative temperature anomalies prevailed there in the 2000-2001 winter, when the NAO index was negative, but such anomalies were not evident in PWV. In addition to such

  6. GPS Metric Tracking Unit

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As Global Positioning Satellite (GPS) applications become more prevalent for land- and air-based vehicles, GPS applications for space vehicles will also increase. The Applied Technology Directorate of Kennedy Space Center (KSC) has developed a lightweight, low-cost GPS Metric Tracking Unit (GMTU), the first of two steps in developing a lightweight, low-cost Space-Based Tracking and Command Subsystem (STACS) designed to meet Range Safety's link margin and latency requirements for vehicle command and telemetry data. The goals of STACS are to improve Range Safety operations and expand tracking capabilities for space vehicles. STACS will track the vehicle, receive commands, and send telemetry data through the space-based asset, which will dramatically reduce dependence on ground-based assets. The other step was the Low-Cost Tracking and Data Relay Satellite System (TDRSS) Transceiver (LCT2), developed by the Wallops Flight Facility (WFF), which allows the vehicle to communicate with a geosynchronous relay satellite. Although the GMTU and LCT2 were independently implemented and tested, the design collaboration of KSC and WFF engineers allowed GMTU and LCT2 to be integrated into one enclosure, leading to the final STACS. In operation, GMTU needs only a radio frequency (RF) input from a GPS antenna and outputs position and velocity data to the vehicle through a serial or pulse code modulation (PCM) interface. GMTU includes one commercial GPS receiver board and a custom board, the Command and Telemetry Processor (CTP) developed by KSC. The CTP design is based on a field-programmable gate array (FPGA) with embedded processors to support GPS functions.

  7. Long-term object tracking combined offline with online learning

    NASA Astrophysics Data System (ADS)

    Hu, Mengjie; Wei, Zhenzhong; Zhang, Guangjun

    2016-04-01

    We propose a simple yet effective method for long-term object tracking. Different from the traditional visual tracking method, which mainly depends on frame-to-frame correspondence, we combine high-level semantic information with low-level correspondences. Our framework is formulated in a confidence selection framework, which allows our system to recover from drift and partly deal with occlusion. To summarize, our algorithm can be roughly decomposed into an initialization stage and a tracking stage. In the initialization stage, an offline detector is trained to get the object appearance information at the category level, which is used for detecting the potential target and initializing the tracking stage. The tracking stage consists of three modules: the online tracking module, detection module, and decision module. A pretrained detector is used for maintaining drift of the online tracker, while the online tracker is used for filtering out false positive detections. A confidence selection mechanism is proposed to optimize the object location based on the online tracker and detection. If the target is lost, the pretrained detector is utilized to reinitialize the whole algorithm when the target is relocated. During experiments, we evaluate our method on several challenging video sequences, and it demonstrates huge improvement compared with detection and online tracking only.

  8. Recognition of ships for long-term tracking

    NASA Astrophysics Data System (ADS)

    van den Broek, Sebastiaan P.; Bouma, Henri; Veerman, Henny E. T.; Benoist, Koen W.; den Hollander, Richard J. M.; Schwering, Piet B. W.

    2014-06-01

    Long-term tracking is important for maritime situational awareness to identify currently observed ships as earlier encounters. In cases of, for example, piracy and smuggling, past location and behavior analysis are useful to determine whether a ship is of interest. Furthermore, it is beneficial to make this assessment with sensors (such as cameras) at a distance, to avoid costs of bringing an own asset closer to the ship for verification. The emphasis of the research presented in this paper, is on the use of several feature extraction and matching methods for recognizing ships from electro-optical imagery within different categories of vessels. We compared central moments, SIFT with localization and SIFT with Fisher Vectors. From the evaluation on imagery of ships, an indication of discriminative power is obtained between and within different categories of ships. This is used to assess the usefulness in persistent tracking, from short intervals (track improvement) to larger intervals (re-identifying ships). The result of this assessment on real data is used in a simulation environment to determine how track continuity is improved. The simulations showed that even limited recognition will improve tracking, connecting both tracks at short intervals as well as over several days.

  9. Long term frequency stability analysis of the GPS NAVSTAR 6 Cesium clock

    NASA Technical Reports Server (NTRS)

    Mccaskill, T. B.; Stebbins, S.; Carson, C.; Buisson, J.

    1982-01-01

    Time domain measurements, taken between the NAVSTAR 6 Spacecraft Vehicle (SV) and the Vandenberg Global Positioning System (GPS) Monitor Site, by a pseudo random noise receiver, were collected over an extended period of time and analyzed to estimate the long term frequency stability of the NAVSTAR 6 onboard frequency standard, referenced to the Vandenberg MS frequency standard. The technique employed separates the clock offset from the composite signal by first applying corrections for equipment delays, ionospheric delay, tropospheric delay, Earth rotation and the relativistic effect. The data are edited and smoothed using the predicted SV ephemeris to calculate the geometric delay. Then all available passes from each of the four GPS monitor stations, are collected at 1-week intervals and used to calculate the NAVSTAR orbital elements. The procedure is then completed by subtracting the corrections and the geometric delay, using the final orbital elements, from the composite signal, thus leaving the clock offset and random error.

  10. Long-term evolution of navigation satellite orbits: GPS/GLONASS/GALILEO

    NASA Astrophysics Data System (ADS)

    Chao, C.; Gick, R.

    Earlier studies conducted a The Aerospace Corporation discovered that the GPSt Block II satellites placed in disposal orbits can eventually, perhaps in 20 to 40 years, reenter into the operating constellation. This is because the disposal orbits, while circular initially, evolve int o orbits with significant eccentricity mostly as the result of sun-moon gravitational perturbations. Options of minimizing the eccentricity growth include reducing initial eccentricity of the disposal orbit and inserting into an orbit with a favorable argument of perigee. A recent study was performed to examine whether the same long-term eccentricity evolution exists for the disposal orbits of other navigation satellite systems such as GLONASS and GALILEO. The non-operational GPS Block I satellites are included in the study as well, because the orbits are at 63.4 deg inclination, which is different from that of the GPS Block II satellites. Similar to the earlier studies, long-term perturbations and stability of these orbits were understood through analytical and numerical investigations. Two-hundred-year semi-analytic integration revealed interesting facts about the orbit stability. Initially near circular, these types of orbits may evolve into orbits with large eccentricity (as much as 0.7 over 150 years). Analytical approximations through doubly-averaged equations reveal that the cause is due to the resonance induced by Sun/moon and J2 secular perturbations. A total of 113 non-operational GLONASS satellites and upper stages and 10 GPS/Block I satellites were propagated for 200 years using a high-precision semi-analytical propagator (MEANPROP). Results show that the GLONASS satellites will start to enter the operating GPS constellation after 40 years. The uncovered resonance effect is strongly dependent on o bit inclination and altitude. The effect becomes morer pronounced for GALILEO orbits due to a higher altitude, 3000 km above GPS. Strategies to minimize the significant

  11. Evaluation of long term solar activity effects on GPS derived TEC

    NASA Astrophysics Data System (ADS)

    Mansoori, Azad A.; Khan, Parvaiz A.; Ahmad, Rafi; Atulkar, Roshni; M, Aslam A.; Bhardwaj, Shivangi; Malvi, Bhupendra; Purohit, P. K.; Gwal, A. K.

    2016-10-01

    The solar activity hence the solar radiance follows a long term periodic variability with eleven years periodicity, known as solar cycle. This drives the long term variability of the ionosphere. In the present problem we investigate the long term behaviour of the ionosphere with the eleven year cyclic solar activity. Under the present study we characterize the ionospheric variability by Total Electron Content (TEC) using measurements made by Global Positioning System (GPS) and solar cycle variability by various solar activity indices. We make use of five solar activity indices viz. sunspot number (Rz), solar radio Flux (F10.7 cm), EUV Flux (26-34 nm), flare index and CME occurrences. The long term variability of these solar activity indices were then compared and correlated with the variability of ionospheric TEC, at a mid latitude station, Usuda (36.13N, 138.36E), of Japan, during the solar cycle 23 and ascending phase of cycle 24. From our study, we found that long term changes in the ionospheric TEC vary synchronously with corresponding changes in the solar activity indices. The correlation analysis shows that all the solar activity indices exhibit a very strong correlation with TEC (R =0.76 -0.99). Moreover the correlation between the two is stronger in the descending phase of the solar cycle. The correlation is found to be remarkably strongest during the deep minimum of the solar cycle 24 i.e. between 2007- 2009. Also we noticed a hysteresis effect exists with solar radio flux (F10.7 cm) and solar EUV flux (26-34 nm). This effect is absent with other parameters.

  12. Evaluating multimodel variability of humidity over Europe using long term GPS network and ground base datasets

    NASA Astrophysics Data System (ADS)

    Bastin, Sophie; Bock, Olivier; Parracho, Ana

    2016-04-01

    Thanks to efforts made to reanalyse observed data to produce long-term homogenized datasets of new parameters or multi-parameters in recent years, we can better characterize, evaluate and analyse the water cycle in models at different scales. In this paper, a few MED-CORDEX simulations covering the ERA-interim period are evaluated against reprocessed IWV from GPS datasets over the European domain, from 1995 to 2008. The humidity is an important component of the water cycle, and models often have difficulties representing it. The high quality, consistent, long-term IWV dataset recently produced from GPS at more than 100 stations over Europe, with about half of the stations having nearly 15 years of data over the period from 1995 to 2010 is therefore used to evaluate the simulated IWV at seasonal, interannual and possibly diurnal time scales. Regional features are then identified, corresponding to different climate regimes. Other datasets, such as reanalysis of multi-parameters observed at one site (SIRTA, Palaiseau, France) over more than 10 years, or more regional networks are used to explain the dispersion of IWV among the different models and their biases against observations. The relationship between IWV and surface temperature is also evaluated locally to assess how much the sources of humidity from advection or surface fluxes are enough to reach the total capacity of the atmosphere in humidity when temperature increases. Over arid areas, this relation can depart from the Clausius-Clapeyron relation when temperature becomes too high. The ability of models to reproduce this relation during present climate is of high importance to estimate future climate.

  13. Long-term antidepressant use: a qualitative study on perspectives of patients and GPs in primary care.

    PubMed

    Bosman, Renske C; Huijbregts, Klaas M; Verhaak, Peter Fm; Ruhé, Henricus G; van Marwijk, Harm Wj; van Balkom, Anton Jlm; Batelaan, Neeltje M

    2016-10-01

    Antidepressant use is often prolonged in patients with anxiety and/or depressive disorder(s) compared with recommendations in treatment guidelines to discontinue after sustained remission. To unravel the motivations of patients and GPs causing long-term antidepressant use and to gain insight into possibilities to prevent unnecessary long-term use. Qualitative study using semi-structured, in-depth interviews with patients and GPs in the Netherlands. Patients with anxiety and/or depressive disorder(s) (n = 38) and GPs (n = 26) were interviewed. Innovatively, the interplay between patients and their GPs was also investigated by means of patient-GP dyads (n = 20). The motives and barriers of patients and GPs to continue or discontinue antidepressants were related to the availability of supportive guidance during discontinuation, the personal circumstances of the patient, and considerations of the patient or GP. Importantly, dyads indicated a large variation in policies of general practices around long-term use and continuation or discontinuation of antidepressants. Dyads further indicated that patients and GPs seemed unaware of each other's (mismatching) expectations regarding responsibility to initiate discussing continuation or discontinuation. Although motives and barriers to antidepressant continuation or discontinuation were related to the same themes for patients and GPs, dyads indicated discrepancies between them. Discussion between patients and GPs about antidepressant use and continuation or discontinuation may help clarify mutual expectations and opinions. Agreements between a patient and their GP can be included in a patient-tailored treatment plan. © British Journal of General Practice 2016.

  14. A Long-Term Comparison Between GPS Carrier-Phase and Two-Way Satellite Time Transfer

    DTIC Science & Technology

    1998-12-01

    90th Annual Precise Time and Time Interval (PTTI) Meeting A LONG-TERM COMPARISON BETWEEN GPS CARRIER-PHASE AND TWO-WAY SATELLITE TIME TRANSFER...7881 e-mail kristine.larson@colorado.edu Lisa Nelson, Judah Levine, and Tom Parker NIST Time and Frequency Division Boulder, CO 80303 Edward D...Powers Time Service ~ e ~ a r t m e n t , USNO Washington, DC 20392 Abstract We have conducted GPS carrier-phase time -transfer experiments

  15. Accuracy of Tracking Forest Machines with GPS

    Treesearch

    M.W. Veal; S.E. Taylor; T.P. McDonald; D.K. McLemore; M.R. Dunn

    2001-01-01

    This paper describes the results of a study that measured the accuracy of using GPS to track movement offorest machines. Two different commercially available GPS receivers (Trimble ProXR and GeoExplorer II) were used to track wheeled skidders under three different canopy conditions at two different vehicle speeds. Dynamic GPS data were compared to position data...

  16. Sensitivity of train stochastic dynamics to long-term evolution of track irregularities

    NASA Astrophysics Data System (ADS)

    Lestoille, N.; Soize, C.; Funfschilling, C.

    2016-05-01

    The influence of the track geometry on the dynamic response of the train is of great concern for the railway companies, because they have to guarantee the safety of the train passengers in ensuring the stability of the train. In this paper, the long-term evolution of the dynamic response of the train on a stretch of the railway track is studied with respect to the long-term evolution of the track geometry. The characterisation of the long-term evolution of the train response allows the railway companies to start off maintenance operations of the track at the best moment. The study is performed using measurements of the track geometry, which are carried out very regularly by a measuring train. A stochastic model of the studied stretch of track is created in order to take into account the measurement uncertainties in the track geometry. The dynamic response of the train is simulated with a multibody software. A noise is added in output of the simulation to consider the uncertainties in the computational model of the train dynamics. Indicators on the dynamic response of the train are defined, allowing to visualize the long-term evolution of the stability and the comfort of the train, when the track geometry deteriorates.

  17. Animal Tracking ARGOS vs GPS

    NASA Astrophysics Data System (ADS)

    Robinson, P. W.; Costa, D.; Arnould, J.; Weise, M.; Kuhn, C.; Simmons, S. E.; Villegas, S.; Tremblay, Y.

    2006-12-01

    ARGOS satellite tracking technology has enabled a tremendous increase in our understanding of the movement patterns of a diverse array of marine vertebrates from Sharks to marine mammals. Our current understanding has moved from simple descriptions of large scale migratory patterns to much more sophisticated comparisons of animal movements and behavior relative to oceanic features. Further, animals are increasingly used to carry sensors that can acquire water column temperature and salinity profiles. However, a major limitation of this work is the spatial precision of ARGOS locations. ARGOS provides 7 location qualities that range from 3,2,1,0,A,B,Z and correspond to locations with a precision of 150m to tens of kilometers. Until recently, GPS technology could not be effectively used with marine mammals because they did not spend sufficient time at the surface to allow complete acquisition of satellite information. The recent development of Fastloc technology has allowed the development of GPS tags that can be deployed on marine mammals. Here we compare the location quality and frequency derived from standard ARGOS PTTs to Fastloc GPS locations acquired from 11 northern elephant seals, 5 California and 5 Galapagos sea lions and 1 Cape and 3 Australian fur seals. Our results indicate that GPS technology will greatly enhance our ability to understand the movement patterns of marine vertebrates and the in-situ oceanographic data they collect.

  18. A C++ Framework for Conducting High-Speed, Long-Term Particle Tracking Simulations

    SciTech Connect

    Kabel, A.C.; /SLAC

    2006-02-06

    For the purpose of conducting parallel, long-term tracking studies of storage rings such as the ones described in [3], [4], maximum execution speed is essential. We describe an approach involving metaprogramming techniques in C++ which results in execution speeds rivaling hand-optimized assembler code for a particular tracking lattice while retaining the generality and flexibility of an all-purpose tracking code.

  19. 25 years long-term deformation at Mt. Etna Continuous Borehole Tilt and Vertical GPS Displacements recordings

    NASA Astrophysics Data System (ADS)

    Bonaccorso, Alessandro; Bonforte, Alessandro; Gambino, Salvatore

    2016-04-01

    In the 1980s, shallow borehole tilt measurements saw a reprise in the monitoring of geodynamic active areas, while from the beginning of the 1990s the Global Positioning System (GPS) development also provided the opportunity to repeat geodetic measurements in geodynamic and volcanic areas. At Mt. Etna, the continuous measurements from shallow borehole tiltmeters have been successfully used to infer the mechanisms of magma accumulation and intrusive processes that foreran and accompanied the several eruptions occurring during the last thirty years on this very active volcano. The long-term deformation, associated with unrest and/or eruptive phases, is expected to be larger than tectonic deformation and therefore significant long-lived trends could be detected. For the first time, we present 25 years (1990 - 2014) of continuous borehole tilt recorded at Etna volcano at different stations and vertical displacement periodically measured by GPS. We analyze long-term series that comprise several main flank eruptions, which we believe are unique in the landscape of instrumental monitoring of geodynamic active areas. The good similarity of the patterns obtained from the two independent long-term measurements (borehole tilt and GPS) confirms the long-term stability of the borehole signals, the overall reliability of vertical GPS variations and provides robust support to the interpretation on the volcano dynamics. The tilt and GPS data series reveal that during this lengthy period, there were two primary volcanic phases: i) a major recharging in the period 1994 - 2001 that culminated with the two major explosive-effusive flank eruptions in 2001 and 2002-2003, and ii) a subsequent prolonged period of re-equilibrium that was accompanied by three other effusive flank eruptions and 44 episodes of lava fountains in 2011-2013. This highlights that, in the long-term (tens of years), a single strong recharge phase may not imply a following single main eruption, but could even

  20. Low speed, long term tracking electric drive system has zero backlash

    NASA Technical Reports Server (NTRS)

    Richter, H. L.; Stoller, F. W.

    1967-01-01

    Electric drive system provides low speed, long term tracking of targets that move at a sidereal rate. It utilizes eddy-current energized actuators that are free from radio frequency interference generation and a solid state feedback amplifier with provisions for antibacklash biasing.

  1. Accuracy of tracking forest machines with GPS

    Treesearch

    M.W. Veal; S.E. Taylor; T.P. McDonald; D.K. McLemore; M.R. Dunn

    2001-01-01

    This paper describes the results of a study that measured the accuracy of using GPS to track movement of forest machines. Two different commercially available GPS receivers (Trimble ProXR and GeoExplorer II) were used to track\\r\

  2. Prediction of Individual Social-Demographic Role Based on Travel Behavior Variability Using Long-Term GPS Data

    DOE PAGES

    Zhu, Lei; Gonder, Jeffrey; Lin, Lei

    2017-08-16

    With the development of and advances in smartphones and global positioning system (GPS) devices, travelers’ long-term travel behaviors are not impossible to obtain. This study investigates the pattern of individual travel behavior and its correlation with social-demographic features. For different social-demographic groups (e.g., full-time employees and students), the individual travel behavior may have specific temporal-spatial-mobile constraints. The study first extracts the home-based tours, including Home-to-Home and Home-to-Non-Home, from long-term raw GPS data. The travel behavior pattern is then delineated by home-based tour features, such as departure time, destination location entropy, travel time, and driving time ratio. The travel behavior variabilitymore » describes the variances of travelers’ activity behavior features for an extended period. After that, the variability pattern of an individual’s travel behavior is used for estimating the individual’s social-demographic information, such as social-demographic role, by a supervised learning approach, support vector machine. In this study, a long-term (18-month) recorded GPS data set from Puget Sound Regional Council is used. The experiment’s result is very promising. In conclusion, the sensitivity analysis shows that as the number of tours thresholds increases, the variability of most travel behavior features converges, while the prediction performance may not change for the fixed test data.« less

  3. Prediction of Individual Social-Demographic Role Based on Travel Behavior Variability Using Long-Term GPS Data

    SciTech Connect

    Zhu, Lei; Gonder, Jeffrey; Lin, Lei

    2017-01-01

    With the development of and advances in smartphones and global positioning system (GPS) devices, travelers’ long-term travel behaviors are not impossible to obtain. This study investigates the pattern of individual travel behavior and its correlation with social-demographic features. For different social-demographic groups (e.g., full-time employees and students), the individual travel behavior may have specific temporal-spatial-mobile constraints. The study first extracts the home-based tours, including Home-to-Home and Home-to-Non-Home, from long-term raw GPS data. The travel behavior pattern is then delineated by home-based tour features, such as departure time, destination location entropy, travel time, and driving time ratio. The travel behavior variability describes the variances of travelers’ activity behavior features for an extended period. After that, the variability pattern of an individual’s travel behavior is used for estimating the individual’s social-demographic information, such as social-demographic role, by a supervised learning approach, support vector machine. In this study, a long-term (18-month) recorded GPS data set from Puget Sound Regional Council is used. The experiment’s result is very promising. The sensitivity analysis shows that as the number of tours thresholds increases, the variability of most travel behavior features converges, while the prediction performance may not change for the fixed test data.

  4. Long-Term Tracking of a Specific Vehicle Using Airborne Optical Camera Systems

    NASA Astrophysics Data System (ADS)

    Kurz, F.; Rosenbaum, D.; Runge, H.; Cerra, D.; Mattyus, G.; Reinartz, P.

    2016-06-01

    In this paper we present two low cost, airborne sensor systems capable of long-term vehicle tracking. Based on the properties of the sensors, a method for automatic real-time, long-term tracking of individual vehicles is presented. This combines the detection and tracking of the vehicle in low frame rate image sequences and applies the lagged Cell Transmission Model (CTM) to handle longer tracking outages occurring in complex traffic situations, e.g. tunnels. The CTM model uses the traffic conditions in the proximities of the target vehicle and estimates its motion to predict the position where it reappears. The method is validated on an airborne image sequence acquired from a helicopter. Several reference vehicles are tracked within a range of 500m in a complex urban traffic situation. An artificial tracking outage of 240m is simulated, which is handled by the CTM. For this, all the vehicles in the close proximity are automatically detected and tracked to estimate the basic density-flow relations of the CTM model. Finally, the real and simulated trajectories of the reference vehicles in the outage are compared showing good correspondence also in congested traffic situations.

  5. Highly Fluorescent and Photostable Polymeric Nanofibers as Scaffolds for Cell Interfacing and Long-Term Tracking.

    PubMed

    Diao, Hua Jia; Wang, Kai; Long, Hong Yan; Wang, Mingfeng; Chew, Sing Yan

    2016-03-09

    Highly fluorescent polymeric nanofibers fabricated via electrospinning of PCL-DPP-PCL (photostable polycaprolactones-di(thiophene-2-yl)-diketopyrrolopyrrole-photostable polycaprolactones) and commercial PCL mixture show superior photostability and cytocompatibility for long-term tracking of cell-substrate interaction. As a proof of concept, these PCL-DPP-PCL nanofibers enable clear visualization of intricate cell-substrate interactions such as oligodendrocyte myelination.

  6. NASA's GPS tracking system for Aristoteles

    NASA Astrophysics Data System (ADS)

    Davis, E. S.; Hajj, G.; Kursinski, E. R.; Kyriacou, C.; Meehan, T. K.; Melbourne, William G.; Neilan, R. E.; Young, L. E.; Yunck, Thomas P.

    1991-12-01

    NASA 's Global Positioning System (GPS) tracking system for Artistoteles receivers and a GPS flight receiver aboard Aristoteles is described. It will include a global network of GPS ground receivers and a GPS flight receiver aboard Aristoteles. The flight receiver will operate autonomously; it will provide real time navigation solutions for Aristoteles and tracking data needed by ESOC for operational control of the satellite. The GPS flight and ground receivers will currently and continuously track all visible GPS satellites. These observations will yield high accuracy differential positions and velocities of Aristoteles in a terrestrial frame defined by the locations of the globally distributed ground work. The precise orbits and tracking data will be made available to science investigators as part of the geophysical data record. The characteristics of the GPS receivers, both flight and ground based, that NASA will be using to support Aristoteles are described. The operational aspects of the overall tracking system, including the data functions and the resulting data products are summarized. The expected performance of the tracking system is compared to Aristoteles requirements and the need to control key error sources such as multipath is identified.

  7. Long-Term Instability of GPS-Based Time Transfer and Proposals for Improvements

    DTIC Science & Technology

    2011-01-01

    VARIATIONS OF THE RECEIVER CALIBRATIONS In the analysis, the standard CGGTTS and PPP data were combined to produce hourly or daily data, and these were...provide GPS data (RINEX and CGGTTS ) from a DICOM GTR50 receiver and just started to operate a Septentrio PolaRx4, which will in the future provide GPS...The BIPM is developing a standard CGGTTS code- based, common-clock CV comparison procedure to continuously check the stabilities of the equipment

  8. Operational improvements of long-term predicted ephemerides of the Tracking and Data Relay Satellites (TDRSs)

    NASA Technical Reports Server (NTRS)

    Kostoff, J. L.; Ward, D. T.; Cuevas, O. O.; Beckman, R. M.

    1995-01-01

    Tracking and Data Relay Satellite (TDRS) orbit determination and prediction are supported by the Flight Dynamics Facility (FDF) of the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD). TDRS System (TDRSS)-user satellites require predicted TDRS ephemerides that are up to 10 weeks in length. Previously, long-term ephemerides generated by the FDF included predictions from the White Sands Complex (WSC), which plans and executes TDRS maneuvers. TDRSs typically have monthly stationkeeping maneuvers, and predicted postmaneuver state vectors are received from WSC up to a month in advance. This paper presents the results of an analysis performed in the FDF to investigate more accurate and economical long-term ephemerides for the TDRSs. As a result of this analysis, two new methods for generating long-term TDRS ephemeris predictions have been implemented by the FDF. The Center-of-Box (COB) method models a TDRS as fixed at the center of its stationkeeping box. Using this method, long-term ephemeris updates are made semiannually instead of weekly. The impulse method is used to model more maneuvers. The impulse method yields better short-term accuracy than the COB method, especially for larger stationkeeping boxes. The accuracy of the impulse method depends primarily on the accuracy of maneuver date forecasting.

  9. Sensing Human Activity: GPS Tracking

    PubMed Central

    van der Spek, Stefan; van Schaick, Jeroen; de Bois, Peter; de Haan, Remco

    2009-01-01

    The enhancement of GPS technology enables the use of GPS devices not only as navigation and orientation tools, but also as instruments used to capture travelled routes: as sensors that measure activity on a city scale or the regional scale. TU Delft developed a process and database architecture for collecting data on pedestrian movement in three European city centres, Norwich, Rouen and Koblenz, and in another experiment for collecting activity data of 13 families in Almere (The Netherlands) for one week. The question posed in this paper is: what is the value of GPS as ‘sensor technology’ measuring activities of people? The conclusion is that GPS offers a widely useable instrument to collect invaluable spatial-temporal data on different scales and in different settings adding new layers of knowledge to urban studies, but the use of GPS-technology and deployment of GPS-devices still offers significant challenges for future research. PMID:22574061

  10. Minimal hardware Bluetooth tracking for long-term at-home elder supervision.

    PubMed

    Kelly, Damian; McLoone, Sean; Farrell, Ronan

    2010-01-01

    The ability to automatically detect the location of an elder within their own home is a significant enabler of remote elder supervision and interaction applications. This location information is typically generated via a myriad of sensors throughout the home environment. Even with high sensor redundancy, there are still situations where traditional elder monitoring systems are unable to resolve the location of the elder. This work develops a minimal infrastructure radio-frequency localisation system for long-term elder location tracking. An RFID room-labelling technique is employed and with it, the localisation system developed in this work is shown to exhibit superior performance to more traditional localisation systems in realistic long-term deployments.

  11. Long-term effects of an educational seminar on antibiotic prescribing by GPs: a randomised controlled trial

    PubMed Central

    Le Corvoisier, Philippe; Renard, Vincent; Roudot-Thoraval, Françoise; Cazalens, Thierry; Veerabudun, Kalaivani; Canoui-Poitrine, Florence; Montagne, Olivier; Attali, Claude

    2013-01-01

    Background High levels of outpatient antibiotic use remain observed in many European countries. Several studies have shown a strong relationship between antibiotic use and bacterial resistance. Aim To assess the long-term effect of a standardised educational seminar on antibiotic prescriptions by GPs. Design and setting Randomised controlled trial of 171 GPs (of 203 initially randomised) in France. Method GPs in the control group (n = 99) received no antibiotic prescription recommendation. Intervention group GPs (n = 72) attended an interactive seminar presenting evidence-based guidelines on antibiotic prescription for respiratory infections. The proportion of prescriptions containing an antibiotic in each group and related costs were compared to the baseline up to 30 months following the intervention. Data were obtained from the National Health Insurance System database. Results In the intervention group, 4–6 months after the intervention, there was a significant decrease in the proportion of prescriptions containing an antibiotic from 15.2 ± 5.4% to 12.3 ± 5.8% (−2.8% [95% CI = −3.8 to −1.9], P<0.001). By contrast, an increase was observed in controls from 15.3 ± 6.0 to 16.4 ± 6.7% (+1.1% [95% CI = +0.4 to +1.8], P<0.01), resulting in a between-group difference of 3.93% ([95% CI = 2.75 to 5.11], P<0.001). The between-group difference was maintained 30 months after intervention (1.99% [95% CI = 0.56 to 3.42], P<0.01). Persistence of the intervention effect over the entire study period was confirmed in a hierarchical multivariate analysis. Conclusion This randomised trial shows that a standardised and interactive educational seminar results in a long-term reduction in antibiotic prescribing and could justify a large-scale implementation of this intervention. PMID:23834882

  12. Video tracking algorithm of long-term experiment using stand-alone recording system

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Jen; Li, Yan-Chay; Huang, Ke-Nung; Jen, Sun-Lon; Young, Ming-Shing

    2008-08-01

    Many medical and behavioral applications require the ability to monitor and quantify the behavior of small animals. In general these animals are confined in small cages. Often these situations involve very large numbers of cages. Modern research facilities commonly monitor simultaneously thousands of animals over long periods of time. However, conventional systems require one personal computer per monitoring platform, which is too complex, expensive, and increases power consumption for large laboratory applications. This paper presents a simplified video tracking algorithm for long-term recording using a stand-alone system. The feature of the presented tracking algorithm revealed that computation speed is very fast data storage requirements are small, and hardware requirements are minimal. The stand-alone system automatically performs tracking and saving acquired data to a secure digital card. The proposed system is designed for video collected at a 640×480 pixel with 16 bit color resolution. The tracking result is updated every 30 frames/s. Only the locomotive data are stored. Therefore, the data storage requirements could be minimized. In addition, detection via the designed algorithm uses the Cb and Cr values of a colored marker affixed to the target to define the tracked position and allows multiobject tracking against complex backgrounds. Preliminary experiment showed that such tracking information stored by the portable and stand-alone system could provide comprehensive information on the animal's activity.

  13. Long-term energetic-particle databases from geosynchronous and GPS orbits

    SciTech Connect

    Reedy, R.C.; Belian, R.D.; Clayton, T.E.

    1998-03-01

    The Los Alamos National Laboratory has flown thirteen energetic particle instruments on geosynchronous satellites since 1976 and on seven GPS satellites since 1983. These instruments measure electrons and protons over a wide range of energies. The various instruments and the particles and energies that they measure are described. The measured fluxes are stored at Los Alamos in several databases that are available to outside users.

  14. Development of long-term event memory in preverbal infants: an eye-tracking study.

    PubMed

    Nakano, Tamami; Kitazawa, Shigeru

    2017-03-08

    The development of long-term event memory in preverbal infants remains elusive. To address this issue, we applied an eye-tracking method that successfully revealed in great apes that they have long-term memory of single events. Six-, 12-, 18- and 24-month-old infants watched a video story in which an aggressive ape-looking character came out from one of two identical doors. While viewing the same video again 24 hours later, 18- and 24-month-old infants anticipatorily looked at the door where the character would show up before it actually came out, but 6- and 12-month-old infants did not. Next, 12-, 18- and 24-month-old infants watched a different video story, in which a human grabbed one of two objects to hit back at the character. In their second viewing after a 24-hour delay, 18- and 24-month-old infants increased viewing time on the objects before the character grabbed one. In this viewing, 24-month-old infants preferentially looked at the object that the human had used, but 18-month-old infants did not show such preference. Our results show that infants at 18 months of age have developed long-term event memory, an ability to encode and retrieve a one-time event and this ability is elaborated thereafter.

  15. Development of long-term event memory in preverbal infants: an eye-tracking study

    PubMed Central

    Nakano, Tamami; Kitazawa, Shigeru

    2017-01-01

    The development of long-term event memory in preverbal infants remains elusive. To address this issue, we applied an eye-tracking method that successfully revealed in great apes that they have long-term memory of single events. Six-, 12-, 18- and 24-month-old infants watched a video story in which an aggressive ape-looking character came out from one of two identical doors. While viewing the same video again 24 hours later, 18- and 24-month-old infants anticipatorily looked at the door where the character would show up before it actually came out, but 6- and 12-month-old infants did not. Next, 12-, 18- and 24-month-old infants watched a different video story, in which a human grabbed one of two objects to hit back at the character. In their second viewing after a 24-hour delay, 18- and 24-month-old infants increased viewing time on the objects before the character grabbed one. In this viewing, 24-month-old infants preferentially looked at the object that the human had used, but 18-month-old infants did not show such preference. Our results show that infants at 18 months of age have developed long-term event memory, an ability to encode and retrieve a one-time event and this ability is elaborated thereafter. PMID:28272489

  16. Long-term time-lapse multimodal microscopy for tracking cell dynamics in live tissue

    NASA Astrophysics Data System (ADS)

    Graf, Benedikt W.; Valero, Maria C.; Chaney, Eric J.; Marjanovic, Marina; Boppart, Marni D.; Boppart, Stephen A.

    2011-02-01

    High speed intravital microscopy has emerged as an essential tool for studying cellular dynamics in live tissue. A limitation of this technique, however, is that the timescale that a sample can be continuously imaged is limited by practical considerations to several hours. Long term observation of live tissue is of great interest for a variety of research areas. We present methods for observing long term cellular dynamics in live tissue based on three-dimensional registration of time-lapse intravital microscopy images. For these experiments we utilized a custom multimodal microscope that allows simultaneous and co-registered acquisition of optical coherence (OCM) and multiphoton (MPM) microscopy images. OCM allows the structure of a sample to be visualized based on backscattered light while MPM excited fluorescence allows individual cells and cell function to be visualized. The OCM images of tissue structure are used to register data sets taken at different time points. The transformations of the OCM images are applied to MPM images to determine the migration of cell populations. This method of image registration is applied to in vivo tracking of bone-marrow derived GFP-labeled stem cells in mouse skin following bone marrow transplants from GFP donors into species-matched wildtype hosts. The use of three-dimensional image registration of time-lapse microscopy images enables tracking these cells after local cutaneous injury, and for investigating the role of skin stem cells in wound healing.

  17. On the feasibility of tracking with differential-algebra maps in long-term stability studies for large hadron colliders

    SciTech Connect

    Kleiss, R.; Schmidt, F.; Yan, Y.

    1992-01-01

    A time-saving alternative to conventional element-by-element tracking in long-term stability studies is the use of truncated Taylor maps. This report discusses how the non-symplecticity of a moderately high-order truncated Taylor map affects its reliability when the map is used for tracking over several thousand turns. Various machines and two different map-constructing programs are compared. It is found that the discrepancies between the Taylor map results and those obtained by direct tracking grow with amplitude. Thus, such maps are not guaranteed to be sufficient for long-term tracking over millions of turns without suitable symplectification.

  18. High-dynamic GPS tracking

    NASA Technical Reports Server (NTRS)

    Hinedi, S.; Statman, J. I.

    1988-01-01

    The results of comparing four different frequency estimation schemes in the presence of high dynamics and low carrier-to-noise ratios are given. The comparison is based on measured data from a hardware demonstration. The tested algorithms include a digital phase-locked loop, a cross-product automatic frequency tracking loop, and extended Kalman filter, and finally, a fast Fourier transformation-aided cross-product frequency tracking loop. The tracking algorithms are compared on their frequency error performance and their ability to maintain lock during severe maneuvers at various carrier-to-noise ratios. The measured results are shown to agree with simulation results carried out and reported previously.

  19. Long-term Behavioral Tracking of Freely Swimming Weakly Electric Fish

    PubMed Central

    Jun, James J.; Longtin, André; Maler, Leonard

    2014-01-01

    Long-term behavioral tracking can capture and quantify natural animal behaviors, including those occurring infrequently. Behaviors such as exploration and social interactions can be best studied by observing unrestrained, freely behaving animals. Weakly electric fish (WEF) display readily observable exploratory and social behaviors by emitting electric organ discharge (EOD). Here, we describe three effective techniques to synchronously measure the EOD, body position, and posture of a free-swimming WEF for an extended period of time. First, we describe the construction of an experimental tank inside of an isolation chamber designed to block external sources of sensory stimuli such as light, sound, and vibration. The aquarium was partitioned to accommodate four test specimens, and automated gates remotely control the animals' access to the central arena. Second, we describe a precise and reliable real-time EOD timing measurement method from freely swimming WEF. Signal distortions caused by the animal's body movements are corrected by spatial averaging and temporal processing stages. Third, we describe an underwater near-infrared imaging setup to observe unperturbed nocturnal animal behaviors. Infrared light pulses were used to synchronize the timing between the video and the physiological signal over a long recording duration. Our automated tracking software measures the animal's body position and posture reliably in an aquatic scene. In combination, these techniques enable long term observation of spontaneous behavior of freely swimming weakly electric fish in a reliable and precise manner. We believe our method can be similarly applied to the study of other aquatic animals by relating their physiological signals with exploratory or social behaviors. PMID:24637642

  20. A smart homecage system with 3D tracking for long-term behavioral experiments.

    PubMed

    Byunghun Lee; Kiani, Mehdi; Ghovanloo, Maysam

    2014-01-01

    A wirelessly-powered homecage system, called the EnerCage-HC, that is equipped with multi-coil wireless power transfer, closed-loop power control, optical behavioral tracking, and a graphic user interface (GUI) is presented for long-term electrophysiology experiments. The EnerCage-HC system can wirelessly power a mobile unit attached to a small animal subject and also track its behavior in real-time as it is housed inside a standard homecage. The EnerCage-HC system is equipped with one central and four overlapping slanted wire-wound coils (WWCs) with optimal geometries to form 3-and 4-coil power transmission links while operating at 13.56 MHz. Utilizing multi-coil links increases the power transfer efficiency (PTE) compared to conventional 2-coil links and also reduces the number of power amplifiers (PAs) to only one, which significantly reduces the system complexity, cost, and dissipated heat. A Microsoft Kinect installed 90 cm above the homecage localizes the animal position and orientation with 1.6 cm accuracy. An in vivo experiment was conducted on a freely behaving rat by continuously delivering 24 mW to the mobile unit for > 7 hours inside a standard homecage.

  1. Long-term microfluidic tracking of coccoid cyanobacterial cells reveals robust control of division timing.

    PubMed

    Yu, Feiqiao Brian; Willis, Lisa; Chau, Rosanna Man Wah; Zambon, Alessandro; Horowitz, Mark; Bhaya, Devaki; Huang, Kerwyn Casey; Quake, Stephen R

    2017-02-14

    Cyanobacteria are important agents in global carbon and nitrogen cycling and hold great promise for biotechnological applications. Model organisms such as Synechocystis sp. and Synechococcus sp. have advanced our understanding of photosynthetic capacity and circadian behavior, mostly using population-level measurements in which the behavior of individuals cannot be monitored. Synechocystis sp. cells are small and divide slowly, requiring long-term experiments to track single cells. Thus, the cumulative effects of drift over long periods can cause difficulties in monitoring and quantifying cell growth and division dynamics. To overcome this challenge, we enhanced a microfluidic cell-culture device and developed an image analysis pipeline for robust lineage reconstruction. This allowed simultaneous tracking of many cells over multiple generations, and revealed that cells expand exponentially throughout their cell cycle. Generation times were highly correlated for sister cells, but not between mother and daughter cells. Relationships between birth size, division size, and generation time indicated that cell-size control was inconsistent with the "sizer" rule, where division timing is based on cell size, or the "timer" rule, where division occurs after a fixed time interval. Instead, single cell growth statistics were most consistent with the "adder" rule, in which division occurs after a constant increment in cell volume. Cells exposed to light-dark cycles exhibited growth and division only during the light period; dark phases pause but do not disrupt cell-cycle control. Our analyses revealed that the "adder" model can explain both the growth-related statistics of single Synechocystis cells and the correlation between sister cell generation times. We also observed rapid phenotypic response to light-dark transitions at the single cell level, highlighting the critical role of light in cyanobacterial cell-cycle control. Our findings suggest that by monitoring the growth

  2. Long-Term Tracking of Corotating Density Structures Using Heliospheric Imaging

    NASA Astrophysics Data System (ADS)

    Plotnikov, I.; Rouillard, A. P.; Davies, J. A.; Bothmer, V.; Eastwood, J. P.; Gallagher, P.; Harrison, R. A.; Kilpua, E.; Möstl, C.; Perry, C. H.; Rodriguez, L.; Lavraud, B.; Génot, V.; Pinto, R. F.; Sanchez-Diaz, E.

    2016-08-01

    stream interface measured in situ by an average of 55 km s^{-1} at ST-A and 84 km s^{-1} at STEREO-B (ST-B). We show that the speeds of the corotating density structures derived using our fitting technique track well the long-term variation of the radial speed of the slow solar wind during solar minimum years (2007 - 2008). Furthermore, we demonstrate that these features originate near the coronal neutral line that eventually becomes the heliospheric current sheet.

  3. TAGGING, TRACKING AND LOCATING WITHOUT GPS

    SciTech Connect

    Cordaro, J.; Coleman, T.; Shull, D.

    2012-07-08

    The Savannah River National Laboratory (SRNL) was requested to lead a Law Enforcement Working Group that was formed to collaborate on common operational needs. All agencies represented on the working group ranked their need to tag, track, and locate a witting or unwitting target as their highest priority. Specifically, they were looking for technologies more robust than Global Positioning Satellite (GPS), could communicate back to the owner, and worked where normal cell phone communications did not work or were unreliable. SRNL brought together multiple technologies in a demonstration that was held in in various Alaska venues, including metropolitan, wilderness, and at-sea that met the working group's requirements. Using prototypical technologies from Boeing, On Ramp, and Fortress, SRNL was able to demonstrate the ability to track personnel and material in all scenarios including indoors, in heavily wooden areas, canyons, and in parking garages. In all cases GPS signals were too weak to measure. Bi-directional communication was achieved in areas that Wi-Fi, cell towers, or traditional radios would not perform. The results of the exercise will be presented. These technologies are considered ideal for tracking high value material such has nuclear material with a platform that allows seamless tracking anywhere in the world, indoors or outdoors.

  4. Atmospheric oscillations comparison on long term tropospheric delay time series derived from ray-tracing and GPS

    NASA Astrophysics Data System (ADS)

    Nikolaidou, Thalia; Santos, Marcelo

    2017-04-01

    The caused time delay induced by the atmosphere on the GNSS signals (NAD), depends primarily on the amount of atmosphere the signal traverses till it reaches to the Earth's surface and can exceed t 20 m for low elevation angles (around 3 degrees). For a particular ray i.e. satellite/quasar-antenna link, the delay depends on the atmospheric parameters of total pressure, temperature, and the partial pressure of water vapor. Because of that, numerical weather models (NWM) have already proven beneficial for atmospheric modelling and geodesy. By direct raytracing, inside NWM, the VMF1 and the University of New Brunswick VMF1 (UNB-VMF1) (Urquhart et al. 2011), access the 3D variation of the meteorological parameters that determine the delay thus being the state-the-art mapping functions used today. The raytracing procedure is capable of providing NADs delays for any point on the Earth's surface. In this study we study the impact of regional numerical weather models, with high spatial and temporal resolution, namely 25km and 6h. These models outweigh the currently used NWM by having about 2.6 times better spatial resolution. Raytracing through such NWM, using the independent raytracing algorithm develop at UNB (Nievinski, 2009), we acquire superior quality NADs with regional application. We ray-trace for the International GNSS service (IGS) network stations for a time span of 11 years. Benchmarking against the IGS troposphere product is performed to access the accuracy of our results. A periodicity analysis is conducted to examine the signature of atmospheric oscillations on the NAD time series. In order to recognize the NAD periodicities, we compared our product against the GPS-derived IGS troposphere product. Systematic effects within each single technique are identified and long-term NAD stability is accessed.

  5. Using natural archives to track sources and long-term trends of pollution: an introduction

    USGS Publications Warehouse

    Jules Blais,; Rosen, Michael R.; John Smol,

    2015-01-01

    This book explores the myriad ways that environmental archives can be used to study the distribution and long-term trajectories of contaminants. The volume first focuses on reviews that examine the integrity of the historic record, including factors related to hydrology, post-depositional diffusion, and mixing processes. This is followed by a series of chapters dealing with the diverse archives available for long-term studies of environmental pollution.

  6. Robust GPS carrier tracking under ionospheric scintillation

    NASA Astrophysics Data System (ADS)

    Susi, M.; Andreotti, M.; Aquino, M. H.; Dodson, A.

    2013-12-01

    Small scale irregularities present in the ionosphere can induce fast and unpredictable fluctuations of Radio Frequency (RF) signal phase and amplitude. This phenomenon, known as scintillation, can degrade the performance of a GPS receiver leading to cycle slips, increasing the tracking error and also producing a complete loss of lock. In the most severe scenarios, if the tracking of multiple satellites links is prevented, outages in the GPS service can also occur. In order to render a GPS receiver more robust under scintillation, particular attention should be dedicated to the design of the carrier tracking stage, that is the receiver's part most sensitive to these types of phenomenon. This paper exploits the reconfigurability and flexibility of a GPS software receiver to develop a tracking algorithm that is more robust under ionospheric scintillation. For this purpose, first of all, the scintillation level is monitored in real time. Indeed the carrier phase and the post correlation terms obtained by the PLL (Phase Locked Loop) are used to estimate phi60 and S4 [1], the scintillation indices traditionally used to quantify the level of phase and amplitude scintillations, as well as p and T, the spectral parameters of the fluctuations PSD. The effectiveness of the scintillation parameter computation is confirmed by comparing the values obtained by the software receiver and the ones provided by a commercial scintillation monitoring, i.e. the Septentrio PolarxS receiver [2]. Then the above scintillation parameters and the signal carrier to noise density are exploited to tune the carrier tracking algorithm. In case of very weak signals the FLL (Frequency Locked Loop) scheme is selected in order to maintain the signal lock. Otherwise an adaptive bandwidth Phase Locked Loop (PLL) scheme is adopted. The optimum bandwidth for the specific scintillation scenario is evaluated in real time by exploiting the Conker formula [1] for the tracking jitter estimation. The performance

  7. Tracking genetically engineered lymphocytes long-term reveals the dynamics of T cell immunological memory.

    PubMed

    Oliveira, Giacomo; Ruggiero, Eliana; Stanghellini, Maria Teresa Lupo; Cieri, Nicoletta; D'Agostino, Mattia; D'Agostino, Mattio; Fronza, Raffaele; Lulay, Christina; Dionisio, Francesca; Mastaglio, Sara; Greco, Raffaella; Peccatori, Jacopo; Aiuti, Alessandro; Ambrosi, Alessandro; Biasco, Luca; Bondanza, Attilio; Lambiase, Antonio; Traversari, Catia; Vago, Luca; von Kalle, Christof; Schmidt, Manfred; Bordignon, Claudio; Ciceri, Fabio; Bonini, Chiara

    2015-12-09

    Long-lasting immune protection from pathogens and cancer requires the generation of memory T cells able to survive long-term. To unravel the immunological requirements for long-term persistence of human memory T cells, we characterized and traced, over several years, T lymphocytes genetically modified to express the thymidine kinase (TK) suicide gene that were infused in 10 patients after haploidentical hematopoietic stem cell transplantation (HSCT). At 2 to 14 years after infusion and in the presence of a broad and resting immune system, we could still detect effectors/effector memory (TEM/EFF), central memory (TCM), and stem memory (TSCM) TK(+) cells, circulating at low but stable levels in all patients. Longitudinal analysis of cytomegalovirus (CMV)- and Flu-specific TK(+) cells indicated that antigen recognition was dominant in driving in vivo expansion and persistence at detectable levels. The amount of infused TSCM cells positively correlated with early expansion and with the absolute counts of long-term persisting gene-marked cells. By combining T cell sorting with sequencing of integration (IS), TCRα and TCRβ clonal markers, we showed that T cells retrieved long-term were enriched in clones originally shared in different memory T cell subsets, whereas dominant long-term clonotypes appeared to preferentially originate from infused TSCM and TCM clones. Together, these results indicate that long-term persistence of gene-modified memory T cells after haploidentical HSCT is influenced by antigen exposure and by the original phenotype of infused cells. Cancer adoptive immunotherapy might thus benefit from cellular products enriched in lymphocytes with an early-differentiated phenotype.

  8. Tracking short-term biodistribution and long-term clearance of SPIO tracers in magnetic particle imaging.

    PubMed

    Keselman, Paul; Yu, Elaine; Zhou, Xinyi; Goodwill, Patrick; Chandrasekharan, Prashant; Ferguson, R Matthew; Khandhar, Amit; Kemp, Scott; Krishnan, Kannan; Zheng, Bo; Conolly, Steven

    2017-02-08

    Magnetic Particle Imaging (MPI) is an emerging tracer-based medical imaging modality that images non-radioactive, kidney-safe superparamagnetic iron oxide (SPIO) tracers. MPI offers quantitative, high-contrast and high-SNR images, so MPI has exceptional promise for applications such as cell tracking, angiography, brain perfusion, cancer detection, traumatic brain injury and pulmonary imaging. In assessing MPI's utility for applications mentioned above, it is important to be able to assess tracer short-term biodistribution as well as long-term clearance from the body. Here, we describe the biodistribution and clearance for two commonly used tracers in MPI: Ferucarbotran (Meito Sangyo Co., Japan) and LS-oo8 (LodeSpin Labs, Seattle, WA). We successfully demonstrate that 3D MPI is able to quantitatively assess short-term biodistribution, as well as long-term tracking and clearance of these tracers in vivo.

  9. Tracking short-term biodistribution and long-term clearance of SPIO tracers in magnetic particle imaging

    NASA Astrophysics Data System (ADS)

    Keselman, Paul; Yu, Elaine Y.; Zhou, Xinyi Y.; Goodwill, Patrick W.; Chandrasekharan, Prashant; Ferguson, R. Matthew; Khandhar, Amit P.; Kemp, Scott J.; Krishnan, Kannan M.; Zheng, Bo; Conolly, Steven M.

    2017-05-01

    Magnetic particle imaging (MPI) is an emerging tracer-based medical imaging modality that images non-radioactive, kidney-safe superparamagnetic iron oxide (SPIO) tracers. MPI offers quantitative, high-contrast and high-SNR images, so MPI has exceptional promise for applications such as cell tracking, angiography, brain perfusion, cancer detection, traumatic brain injury and pulmonary imaging. In assessing MPI’s utility for applications mentioned above, it is important to be able to assess tracer short-term biodistribution as well as long-term clearance from the body. Here, we describe the biodistribution and clearance for two commonly used tracers in MPI: Ferucarbotran (Meito Sangyo Co., Japan) and LS-oo8 (LodeSpin Labs, Seattle, WA). We successfully demonstrate that 3D MPI is able to quantitatively assess short-term biodistribution, as well as long-term tracking and clearance of these tracers in vivo.

  10. Long-term tracking of budding yeast cells in brightfield microscopy: CellStar and the Evaluation Platform

    PubMed Central

    Versari, Cristian; Stoma, Szymon; Batmanov, Kirill; Llamosi, Artémis; Mroz, Filip; Kaczmarek, Adam; Deyell, Matt

    2017-01-01

    With the continuous expansion of single cell biology, the observation of the behaviour of individual cells over extended durations and with high accuracy has become a problem of central importance. Surprisingly, even for yeast cells that have relatively regular shapes, no solution has been proposed that reaches the high quality required for long-term experiments for segmentation and tracking (S&T) based on brightfield images. Here, we present CellStar, a tool chain designed to achieve good performance in long-term experiments. The key features are the use of a new variant of parametrized active rays for segmentation, a neighbourhood-preserving criterion for tracking, and the use of an iterative approach that incrementally improves S&T quality. A graphical user interface enables manual corrections of S&T errors and their use for the automated correction of other, related errors and for parameter learning. We created a benchmark dataset with manually analysed images and compared CellStar with six other tools, showing its high performance, notably in long-term tracking. As a community effort, we set up a website, the Yeast Image Toolkit, with the benchmark and the Evaluation Platform to gather this and additional information provided by others. PMID:28179544

  11. Long-term tracking of budding yeast cells in brightfield microscopy: CellStar and the Evaluation Platform.

    PubMed

    Versari, Cristian; Stoma, Szymon; Batmanov, Kirill; Llamosi, Artémis; Mroz, Filip; Kaczmarek, Adam; Deyell, Matt; Lhoussaine, Cédric; Hersen, Pascal; Batt, Gregory

    2017-02-01

    With the continuous expansion of single cell biology, the observation of the behaviour of individual cells over extended durations and with high accuracy has become a problem of central importance. Surprisingly, even for yeast cells that have relatively regular shapes, no solution has been proposed that reaches the high quality required for long-term experiments for segmentation and tracking (S&T) based on brightfield images. Here, we present CellStar, a tool chain designed to achieve good performance in long-term experiments. The key features are the use of a new variant of parametrized active rays for segmentation, a neighbourhood-preserving criterion for tracking, and the use of an iterative approach that incrementally improves S&T quality. A graphical user interface enables manual corrections of S&T errors and their use for the automated correction of other, related errors and for parameter learning. We created a benchmark dataset with manually analysed images and compared CellStar with six other tools, showing its high performance, notably in long-term tracking. As a community effort, we set up a website, the Yeast Image Toolkit, with the benchmark and the Evaluation Platform to gather this and additional information provided by others.

  12. Amateur Spectroscopy of Hot Stars. Long term tracking of circumstellar emission

    NASA Astrophysics Data System (ADS)

    Pollmann, E.

    2005-12-01

    The spectroscopic monitoring programs carried out by the Spectroscopy Group of the German ``Vereinigung der Sternfreunde'' are reviewed in light of current research. Potential benefits for the professional community in collaborating and obtain long-term monitoring data otherwise unaccessible due to telescope time restrictions are summarized. The contribution highlights results on specific objects of wide interest, such as the well investigated Be stars zeta Tauri or the S Doradus type variable P Cygni.

  13. Automated long-term tracking and social behavioural phenotyping of animal colonies within a semi-natural environment.

    PubMed

    Weissbrod, Aharon; Shapiro, Alexander; Vasserman, Genadiy; Edry, Liat; Dayan, Molly; Yitzhaky, Assif; Hertzberg, Libi; Feinerman, Ofer; Kimchi, Tali

    2013-01-01

    Social behaviour has a key role in animal survival across species, ranging from insects to primates and humans. However, the biological mechanisms driving natural interactions between multiple animals, over long-term periods, are poorly studied and remain elusive. Rigorous and objective quantification of behavioural parameters within a group poses a major challenge as it requires simultaneous monitoring of the positions of several individuals and comprehensive consideration of many complex factors. Automatic tracking and phenotyping of interacting animals could thus overcome the limitations of manual tracking methods. Here we report a broadly applicable system that automatically tracks the locations of multiple, uniquely identified animals, such as mice, within a semi-natural setting. The system combines video and radio frequency identified tracking data to obtain detailed behavioural profiles of both individuals and groups. We demonstrate the usefulness of these data in characterizing individual phenotypes, interactions between pairs and the collective social organization of groups.

  14. A typical Ztrack'' long-term tracking result for the SSC aperture study

    SciTech Connect

    Yan, Y.; Bourianoff, G. ); Schachinger, L. )

    1990-12-01

    A large amount of supercomputer CPU time has been used for tracking particles in the Superconducting Super Collider (SSC) using a vectorized, multi-tasked post-Teapot tracking program called Ztrack.'' Typically, hundreds of particles with appropriate initial displacements (relative to the closed orbits) are tracked for a hundred thousand turns. One then simply makes a survival plot (turn at which particle is lost versus initial displacements) to determine the dynamic aperture. Occasionally, particles are tracked to a million turns for very selective cases. These numerical studies aid in determining the best aperture for the SSC. 6 refs., 1 fig., 1 tab.

  15. Application of GPS tracking techniques to orbit determination for TDRS

    NASA Technical Reports Server (NTRS)

    Haines, B. J.; Lichten, S. M.; Malla, R. P.; Wu, S. C.

    1993-01-01

    In this paper, we evaluate two fundamentally different approaches to TDRS orbit determination utilizing Global Positioning System (GPS) technology and GPS-related techniques. In the first, a GPS flight receiver is deployed on the TDRSS spacecraft. The TDRS ephemerides are determined using direct ranging to the GPS spacecraft, and no ground network is required. In the second approach, the TDRSS spacecraft broadcast a suitable beacon signal, permitting the simultaneous tracking of GPS and TDRSS satellites from a small ground network. Both strategies can be designed to meet future operational requirements for TDRS-2 orbit determination.

  16. Automated long-term tracking of freely moving animal and functional brain imaging based on fiber optic microscopy

    NASA Astrophysics Data System (ADS)

    Cha, Jaepyeong; Cheon, Gyeong Woo; Kang, Jin U.

    2015-03-01

    In this study, we demonstrate an automated data acquisition/analysis platform for both long-term motion tracking and functional brain imaging in freely moving mice. Our system utilizes a fiber-bundle based fluorescence microscope for 24 hours imaging of cellular activities within the brain while also monitoring corresponding animal behaviors using a NIR camera. Synchronized software and automation of analysis allow quantification of all animal behaviors and their brain activities over extended periods of time. Our platform can be used for interrogation of the brain activities in different behavioral states and is also well-suited for longitudinal studies of cellular activities in freely moving animals.

  17. Long-term temporal tracking of speech rate affects spoken-word recognition.

    PubMed

    Baese-Berk, Melissa M; Heffner, Christopher C; Dilley, Laura C; Pitt, Mark A; Morrill, Tuuli H; McAuley, J Devin

    2014-08-01

    Humans unconsciously track a wide array of distributional characteristics in their sensory environment. Recent research in spoken-language processing has demonstrated that the speech rate surrounding a target region within an utterance influences which words, and how many words, listeners hear later in that utterance. On the basis of hypotheses that listeners track timing information in speech over long timescales, we investigated the possibility that the perception of words is sensitive to speech rate over such a timescale (e.g., an extended conversation). Results demonstrated that listeners tracked variation in the overall pace of speech over an extended duration (analogous to that of a conversation that listeners might have outside the lab) and that this global speech rate influenced which words listeners reported hearing. The effects of speech rate became stronger over time. Our findings are consistent with the hypothesis that neural entrainment by speech occurs on multiple timescales, some lasting more than an hour. © The Author(s) 2014.

  18. Preparedness in Long-Term Care: A Novel Approach to Address Gaps in Evacuation Tracking.

    PubMed

    Prot, Emilie Y; Clements, Bruce

    2017-02-01

    With an aging population, the number of elderly individuals residing in long-term care (LTC) facilities will continue to grow and pose unique challenges to disaster preparedness and response. With this rapidly growing vulnerable population, it becomes imperative to identify enhanced and novel preparedness strategies and measures. LTC residents not only have complicated medical needs, including the timing of dispensing multiple medications, but frequently have cognitive and mobility deficits as well. In nearly every major disaster, elderly populations have suffered disproportionate morbidity and mortality. This is often due to elderly evacuees getting overlooked in the chaos of an initial response. Instituting measures to rapidly recognize this population in a crowd during an evacuation will reduce their risk. This commentary reviews the LTC facility evacuation challenges of the 2013 explosion of the West Fertilizer Company plant in West, Texas, and offers a novel solution of mandating the wearing of pink vests by all nursing home residents in case of an evacuation. The pink vests quickly alert disaster rescue and response workers of LTC residents with special needs. (Disaster Med Public Health Preparedness. 2017;11:28-30).

  19. Tracking Plasticity: Effects of Long-Term Rehearsal in Expert Dancers Encoding Music to Movement

    PubMed Central

    Bar, Rachel J.; DeSouza, Joseph F. X.

    2016-01-01

    Our knowledge of neural plasticity suggests that neural networks show adaptation to environmental and intrinsic change. In particular, studies investigating the neuroplastic changes associated with learning and practicing motor tasks have shown that practicing such tasks results in an increase in neural activation in several specific brain regions. However, studies comparing experts and non-experts suggest that experts employ less neuronal activation than non-experts when performing a familiar motor task. Here, we aimed to determine the long-term changes in neural networks associated with learning a new dance in professional ballet dancers over 34 weeks. Subjects visualized dance movements to music while undergoing fMRI scanning at four time points over 34-weeks. Results demonstrated that initial learning and performance at seven weeks led to increases in activation in cortical regions during visualization compared to the first week. However, at 34 weeks, the cortical networks showed reduced activation compared to week seven. Specifically, motor learning and performance over the 34 weeks showed the typical inverted-U-shaped function of learning. Further, our result demonstrate that learning of a motor sequence of dance movements to music in the real world can be visualized by expert dancers using fMRI and capture highly significant modeled fits of the brain network variance of BOLD signals from early learning to expert level performance. PMID:26824475

  20. Tracking Plasticity: Effects of Long-Term Rehearsal in Expert Dancers Encoding Music to Movement.

    PubMed

    Bar, Rachel J; DeSouza, Joseph F X

    2016-01-01

    Our knowledge of neural plasticity suggests that neural networks show adaptation to environmental and intrinsic change. In particular, studies investigating the neuroplastic changes associated with learning and practicing motor tasks have shown that practicing such tasks results in an increase in neural activation in several specific brain regions. However, studies comparing experts and non-experts suggest that experts employ less neuronal activation than non-experts when performing a familiar motor task. Here, we aimed to determine the long-term changes in neural networks associated with learning a new dance in professional ballet dancers over 34 weeks. Subjects visualized dance movements to music while undergoing fMRI scanning at four time points over 34-weeks. Results demonstrated that initial learning and performance at seven weeks led to increases in activation in cortical regions during visualization compared to the first week. However, at 34 weeks, the cortical networks showed reduced activation compared to week seven. Specifically, motor learning and performance over the 34 weeks showed the typical inverted-U-shaped function of learning. Further, our result demonstrate that learning of a motor sequence of dance movements to music in the real world can be visualized by expert dancers using fMRI and capture highly significant modeled fits of the brain network variance of BOLD signals from early learning to expert level performance.

  1. Long-Term Movement of Satellite-Tracked Buoys in the Beaufort Sea.

    DTIC Science & Technology

    1981-06-01

    REPORT 6. Pffor,,,qOrgen,e.en Code 8. Per/orm0nq Orgern0=° , 0o s Reo.r N. 7 . A tire s) D.L. MURPHY, P.A. TEBEAU, and I.M. LISSAUER CGR&DC 12/81 9 ...Cy NC 0,- X - 0--ece 0 o ~z w m > C Dh. > U) z, CL NII CD E E C Z2 0C ii Ca 0 C V c 0 1 E 06 .C- z 5 0 lea a O z B S& LL L C. CL zL L OL 9 a. 1 C(AII z...Small Buoy Hull Used in this Study 5 4 Release Site in the Southeastern Beaufort Sea 7 5 Tracks of Buoys Released on 9 August 1979 8 6 Tracks of Buoys

  2. Long-term tracking of neutrally buoyant tracer particles in two-dimensional fluid flows

    NASA Astrophysics Data System (ADS)

    Pervez, M. S.; Solomon, T. H.

    1994-07-01

    An experimental technique has been developed to produce and to track neutrally buoyant particles in a two-dimensional fluid flow. The key aspect of the technique is the ability to track particles for extended intervals (over an hour), which is essential for quantitative studies of transport and mixing. The approach is composed of two stages. In the first stage, digital image processing hardware partially processes the images, reducing the data rate to 50 kbyte/s (typically) and allowing several hours of data to be stored on a conventional computer disk. In the second stage, programs extract particle trajectories from the reduced data. The approach is tested in an experiment on planetary-type flows in a rotating annulus. In an appendix, a technique is discussed for fabricating wax or crayon particles with arbitrary density.

  3. Comparison of long-term financial implications for five veterinary career tracks.

    PubMed

    Gordon, Meg E; Lloyd, James W; Harris-Kober, Donna L

    2010-08-15

    To compare present values of expected income streams for 5 distinct veterinary medical career tracks. Present value model. AVMA survey data. Present values of expected income streams (net of debt repayment) were created and ranked. Sensitivity to each independent variable was assessed. Career present value at 34 years after graduation (CPV(34)) was highest for board-certified specialist (SP; $2,272,877), followed by practice owner (PO; $2,119,596), practice owner buying into practice after 10 years (PO-10; $1,736,333), SP working three-fourths time (SP3/4; $1,702,744), and general practitioner (GP; $1,221,131). Compared with CPV(34) for SP, other career tracks yielded values of 93.3% (PO), 76.4% (PO-10), 74.9% (SP3/4), and 53.7% (GP). The model was robust to debt, interest rate, loan term, and discount rate but was sensitive to mean starting incomes and mean incomes. Greatest return on time and money invested by a veterinary student is through practicing full-time as an SP or through being a PO. Being an SP or SP3/4 was substantially more lucrative than being a GP and was comparable to being a PO. Practice ownership and working as an SP3/4 may be options for balancing financial gain with free time. Specialty training and practice ownership may be career tracks with the best potential repayment options for veterinarians with a large educational debt. Regardless of the amount of debt, the type of practice, mean incomes in a particular field, personal lifestyle, and professional interests are important factors when deciding among career tracks.

  4. Interseismic deformation along the Mexican Subduction Zone: GPS-constrained coupling, and relationships with seismic and aseismic fault behavior, long term deformation and fault properties

    NASA Astrophysics Data System (ADS)

    Rousset, B.; Graham, S. E.; Cubas, N.; Radiguet, M.; Lasserre, C.; Socquet, A.; Campillo, M.; Walpersdorf, A.; Cotte, N.; DeMets, C.

    2013-12-01

    Recent observations have shown that a large diversity of mechanisms accommodates the deformation on subduction zones interfaces, especially with the discovery of slow slip events. Our study aims at comparing Oaxaca and Guerrero areas in the Mexican subduction zone. In these two areas, slow slip events have been discovered in the vicinity of seismic gaps, as well as tremor activity. We derive a regional, interseismic coupling map based on continuous GPS. It reveals lateral variations of coupling at shallow depth (0-25 km, offshore), with two well coupled zones (coupling > 0.7) alternating with two low coupled zones (coupling < 0.3). Below the continent, the entire zone is highly coupled (>0.7 as well), with a down dip, northern limit between coupled and uncoupled areas that is laterally homogeneous, at a distance of 170 km from the trench. Coupling spatial variations are first analyzed with respect to the spatial extension of Slow Slip Events, Tremors and Earthquakes. The analysis of the long-term morphology (bathymetry, topography, sedimentation, gravity) also highlights longitudinal variations, consistent in overall with the GPS-derived coupling variations. This suggests that these coupling variations are, to the first order, persistent over geological time scales (10^6 yr), and representative of fault plane properties that influence the building of the morphology. A mechanical analysis based on the critical tapper theory aims at reconciling geodetic observations and long term observations by determining lateral variations of frictional properties on critical areas of the subduction interface.

  5. Updated Long Term Fault Slip Rates and Seismic Hazard in the Central Alborz, Iran: New Constraints From InSAR and GPS

    NASA Astrophysics Data System (ADS)

    Weston, J. M.; Shirzaei, M.

    2015-12-01

    The Alborz mountain range, located south of the Caspian Sea, accommodates 30% of the 25 mm/yr convergence between Arabia and Eurasia. The resulting shortening and left lateral motion is distributed over several active fault zones within the Central Alborz. Despite earlier efforts using only GPS data, little is known about the long term rate of vertical deformation and aseismic slip. Several historical earthquakes have affected this region, some of the largest of these events occurred on the Mosha fault which is close to the capital city, Tehran, which has a population of over eight million. Thus, constraining the interseismic slip rates in this region is particularly important. In this study we complement existing horizontal velocities from a regional GPS network, with line of sight velocities from interferometric synthetic aperture radar (InSAR), to provide additional constraints on the vertical deformation and enhance the spatial coverage. Assuming a seismogenic depth of 30 km, based on microseismicity data, we solve for the geometry and long term slip rates on four major fault strands in this region. We obtain a long term slip rate of ~ 3 mm/yr for the Mosha and North Alborz faults, and ~ 10 mm/yr for the Khazar fault and Parchin faults. These rates and fault geometries are in agreement with earlier works, and fit the GPS data well. However, close to the fault traces there are large residuals in the InSAR data, suggesting that there is shallow creep (< 30 km). Therefore, we carry out a subsequent inversion using only the residual InSAR displacements to solve for the distribution of creep within the seismogenic zones on these faults. We find that the Mosha and North Alborz faults remain locked between 0 - 30 km depth, whilst the Parchin and Khazar faults are creeping. This new observation of fault creep has direct implications for the seismic hazard in the region. On the Mosha fault we estimate a slip deficit equivalent to a Mw 7.0 event. The combination of In

  6. Long-term exhumation history of the Inner Mongolian Plateau constrained by apatite fission track analysis

    NASA Astrophysics Data System (ADS)

    Li, Ke; Jolivet, Marc; Zhang, Zhicheng; Li, Jianfeng; Tang, Wenhao

    2016-01-01

    The Inner Mongolian Plateau, along the southeastern flank of the wider Mongolian Plateau, is a vast undulating surface ranging in elevation between 900 and 1500 m above sea level. The peculiar topography of this area is assumed to be closely related to its complex tectono-thermal evolution since Late Paleozoic. The lithospheric structure of the Plateau includes three continental blocks: the Mandula and the Bart Obo blocks form the southern margin of the Central Asian Orogenic Belt in that area, and to the south, the Plateau includes the northern margin of the North China Craton. Apatite fission track (AFT) ages and track length distributions from 13 basement outcrops situated in the main tectonic blocks forming the Inner Mongolian Plateau were determined in order to reconstruct its denudation history. The thermal histories inferred from these data imply multi-phased, differential exhumation/burying processes from the Late Paleozoic to the Early Cretaceous. This complex thermal history is largely related to the Early/Middle Triassic closure of the Paleo-Asian Ocean, the Jurassic closure of the Mongol-Okhotsk Ocean, and the Early Cretaceous orogenic collapse of the Mongol-Okhotsk belt. Finally, since Late Cretaceous, no further major tectonic movement occurred and the Inner Mongolian Plateau has been largely peneplained.

  7. GPS-based system for satellite tracking and geodesy

    NASA Technical Reports Server (NTRS)

    Bertiger, Willy I.; Thornton, Catherine L.

    1989-01-01

    High-performance receivers and data processing systems developed for GPS are reviewed. The GPS Inferred Positioning System (GIPSY) and the Orbiter Analysis and Simulation Software (OASIS) are described. The OASIS software is used to assess GPS system performance using GIPSY for data processing. Consideration is given to parameter estimation for multiday arcs, orbit repeatability, orbit prediction, daily baseline repeatability, agreement with VLBI, and ambiguity resolution. Also, the dual-frequency Rogue receiver, which can track up to eight GPS satellites simultaneously, is discussed.

  8. Biocompatible fluorescent supramolecular nanofibrous hydrogel for long-term cell tracking and tumor imaging applications

    NASA Astrophysics Data System (ADS)

    Wang, Huaimin; Mao, Duo; Wang, Youzhi; Wang, Kai; Yi, Xiaoyong; Kong, Deling; Yang, Zhimou; Liu, Qian; Ding, Dan

    2015-11-01

    Biocompatible peptide-based supramolecular hydrogel has recently emerged as a new and promising system for biomedical applications. In this work, Rhodamine B is employed as a new capping group of self-assembling peptide, which not only provides the driving force for supramolecular nanofibrous hydrogel formation, but also endows the hydrogel with intrinsic fluroescence signal, allowing for various bioimaging applications. The fluorescent peptide nanofibrous hydrogel can be formed via disulfide bond reduction. After dilution of the hydrogel with aqueous solution, the fluorescent nanofiber suspension can be obtained. The resultant nanofibers are able to be internalized by the cancer cells and effectively track the HeLa cells for as long as 7 passages. Using a tumor-bearing mouse model, it is also demonstrated that the fluorescent supramolecular nanofibers can serve as an efficient probe for tumor imaging in a high-contrast manner.

  9. Biocompatible fluorescent supramolecular nanofibrous hydrogel for long-term cell tracking and tumor imaging applications

    PubMed Central

    Wang, Huaimin; Mao, Duo; Wang, Youzhi; Wang, Kai; Yi, Xiaoyong; Kong, Deling; Yang, Zhimou; Liu, Qian; Ding, Dan

    2015-01-01

    Biocompatible peptide-based supramolecular hydrogel has recently emerged as a new and promising system for biomedical applications. In this work, Rhodamine B is employed as a new capping group of self-assembling peptide, which not only provides the driving force for supramolecular nanofibrous hydrogel formation, but also endows the hydrogel with intrinsic fluroescence signal, allowing for various bioimaging applications. The fluorescent peptide nanofibrous hydrogel can be formed via disulfide bond reduction. After dilution of the hydrogel with aqueous solution, the fluorescent nanofiber suspension can be obtained. The resultant nanofibers are able to be internalized by the cancer cells and effectively track the HeLa cells for as long as 7 passages. Using a tumor-bearing mouse model, it is also demonstrated that the fluorescent supramolecular nanofibers can serve as an efficient probe for tumor imaging in a high-contrast manner. PMID:26573372

  10. Detecting seasonal and long-term vertical displacement in the North China Plain using GRACE and GPS

    NASA Astrophysics Data System (ADS)

    Wang, Linsong; Chen, Chao; Du, Jinsong; Wang, Tongqing

    2017-06-01

    In total, 29 continuous Global Positioning System (GPS) time series data together with data from Gravity Recovery and Climate Experiment (GRACE) are analysed to determine the seasonal displacements of surface loadings in the North China Plain (NCP). Results show significant seasonal variations and a strong correlation between GPS and GRACE results in the vertical displacement component; the average correlation and weighted root-mean-squares (WRMS) reduction between GPS and GRACE are 75.6 and 28.9 % respectively, when atmospheric and non-tidal ocean effects were removed, but the annual peak-to-peak amplitude of GPS (1.2-6.3 mm) is greater than the data (1.0-2.2 mm) derived from GRACE. We also calculate the trend rate as well as the seasonal signal caused by the mass load change from GRACE data; the rate of GRACE-derived terrestrial water storage (TWS) loss (after multiplying by the scaling factor) in the NCP was 3.39 cm yr-1 (equivalent to 12.42 km3 yr-1) from 2003 to 2009. For a 10-year time span (2003 to 2012), the rate loss of TWS was 2.57 cm yr-1 (equivalent to 9.41 km3 yr-1), which is consistent with the groundwater storage (GWS) depletion rate (the rate losses of GWS were 2.49 and 2.72 cm yr-1 during 2003-2009 and 2003-2012 respectively) estimated from GRACE-derived results after removing simulated soil moisture (SM) data from the Global Land Data Assimilation System (GLDAS)/Noah model. We also found that GRACE-derived GWS changes are in disagreement with the groundwater level changes from observations of shallow aquifers from 2003 to 2009, especially between 2010 and 2013. Although the shallow groundwater can be recharged from the annual climate-driven rainfall, the important facts indicate that GWS depletion is more serious in deep aquifers. The GRACE-derived result shows an overall uplift in the whole region at the 0.37-0.95 mm yr-1 level from 2004 to 2009, but the rate of change direction is inconsistent in different GPS stations at the -0.40-0.51 mm yr-1

  11. A Mobile GPS Application: Mosque Tracking with Prayer Time Synchronization

    NASA Astrophysics Data System (ADS)

    Hashim, Rathiah; Ikhmatiar, Mohammad Sibghotulloh; Surip, Miswan; Karmin, Masiri; Herawan, Tutut

    Global Positioning System (GPS) is a popular technology applied in many areas and embedded in many devices, facilitating end-users to navigate effectively to user's intended destination via the best calculated route. The ability of GPS to track precisely according to coordinates of specific locations can be utilized to assist a Muslim traveler visiting or passing an unfamiliar place to find the nearest mosque in order to perform his prayer. However, not many techniques have been proposed for Mosque tracking. This paper presents the development of GPS technology in tracking the nearest mosque using mobile application software embedded with the prayer time's synchronization system on a mobile application. The prototype GPS system developed has been successfully incorporated with a map and several mosque locations.

  12. Long term three dimensional tracking of orthodontic patients using registered cone beam CT and photogrammetry.

    PubMed

    Boulanger, Pierre; Flores-Mir, Carlos; Ramirez, Juan F; Mesa, Elizabeth; Branch, John W

    2009-01-01

    The measurements from registered images obtained from Cone Beam Computed Tomography (CBCT) and a photogrammetric sensor are used to track three-dimensional shape variations of orthodontic patients before and after their treatments. The methodology consists of five main steps: (1) the patient's bone and skin shapes are measured in 3D using the fusion of images from a CBCT and a photogrammetric sensor. (2) The bone shape is extracted from the CBCT data using a standard marching cube algorithm. (3) The bone and skin shape measurements are registered using titanium targets located on the head of the patient. (4) Using a manual segmentation technique the head and lower jaw geometry are extracted separately to deal with jaw motion at the different record visits. (5) Using natural features of the upper head the two datasets are then registered with each other and then compared to evaluate bone, teeth, and skin displacements before and after treatments. This procedure is now used at the University of Alberta orthodontic clinic.

  13. Evaluation of solar radio bursts' effect on GPS receiver signal tracking within International GPS Service network

    NASA Astrophysics Data System (ADS)

    Chen, Zhiyu; Gao, Yang; Liu, Zhizhao

    2005-06-01

    The direct interference from solar radio bursts (SRB) has not usually been considered as a potential threat to global positioning system (GPS) signal tracking, since the flux densities of most bursts are below 40,000 solar flux units (sfu), a threat threshold to GPS L1 frequency proposed by Klobuchar et al. (1999). Recent analysis indicated that a much lower threshold should be adopted for codeless or semicodeless dual-frequency GPS receivers. In this investigation, severe signal corruptions were found at dayside International GPS Service GPS receiver stations during a large solar radio burst that accompanied the super flare of 28 October 2003. Almost no GPS L2 signals were tracked during the solar flux peak time for areas near the subsolar point. Correlation analysis was performed between the rate of loss of lock on GPS L2 frequency and solar radio flux density at different bands, and a correlation index as high as 0.75 is revealed in the 1415 MHz solar radiation band, which is located between the two GPS operating frequencies L2 (1227.60 MHz) and L1 (1575.42 MHz). The correlation analysis indicates that GPS signal losses of lock were primarily caused by microwave in-band interference and that the threat threshold of SRB effects on the GPS system should be re-evaluated, since the flux density of the burst at 1415 MHz was just 4,000-12,000 sfu, which is far below the previously proposed threat threshold. The signal-tracking performance of different types of GPS receivers during such a super flare event is also presented.

  14. Long-Term Global Distributions of Mesoscale Variations in Atmospheric Radio Refraction Obtained from the GPS Champ Satellite Data

    NASA Astrophysics Data System (ADS)

    Gavrilov, N. M.; Manuilova, R. O.

    2016-12-01

    We obtain average global distributions of the variances of the mesoscale variations in the atmospheric radio-refraction index (refractive index) at altitudes of 5-35 km from the data of the radio-occultation experiments performed during operation of the low-orbit GPS CHAMP satellite in the period 2001-2009. The filtering of the vertical profiles of the radio-refraction index allows one to determine the variances of the variations with vertical scales below 8 km. The latitudinal-temporal distributions of the zonal-mean variances of the index demonstrate significant interannual variations at various altitudes. Seasonal variations in the variances of radio refraction are studied. Quasi-biennial oscillations at low latitudes are revealed. Acoustic-gravity waves and turbulent and convective motions in the atmosphere can cause a spread of the radio-refraction index.

  15. Long-Term Periodicity of the Mars Exospheric Density from MRO and Mars Odyssey Radio Tracking Data

    NASA Astrophysics Data System (ADS)

    Genova, A.; Goossens, S. J.; Lemoine, F. G.; Mazarico, E.; Smith, D. E.; Zuber, M. T.

    2014-12-01

    The Mars Odyssey and Mars Reconnaissance Orbiter (MRO) missions have collected more than 11 years of continuous tracking data of spacecraft in orbit around Mars. The radio science data are generally used to determine the static and seasonal gravity field of the central body. However, these two spacecraft are in different sun-synchronous orbits that cover a wide range of altitudes (250-410 km) where investigation of the atmosphere and climate of Mars so far have not been supported by in situ and remote sensing measurements. The drag perturbation acting on the probes provides indirect measurements of the Martian atmospheric density. Therefore, we focused our work on the determination of the long-term periodicity of the atmospheric constituents in the Mars exosphere with Mars Odyssey and MRO radio tracking data. We implemented the Drag Temperature Model (DTM) -Mars model into our Precise Orbit Determination (POD) program GEODYN-II to adequately reproduce variations in temperature and (partial) density along ODY and MRO trajectories. The recovery of Mars' atmospheric dynamics using Doppler tracking data requires the accurate modeling of all forces acting on the spacecraft. The main non-conservative force, apart from drag, is solar radiation pressure. Spacecraft panel reflectivities and the radiation pressure-scaling factor are not estimated, but we adjusted empirical once-per-revolution along-track periodic accelerations (cosine and sine) over each orbital arc to mitigate solar radiation pressure mismodeling. After converging the orbital data arcs, and editing out all the data during superior conjunctions, we combined the MRO and Mars Odyssey arcs in a global solution where we estimated spacecraft initial states, time-correlated drag scale factors, and annual and semi-annual variability of the major constituents in the Mars upper atmosphere. We will show that the updated DTM-Mars model provides a better prediction of the long-term variability of the dominant species

  16. Radio-tracking manatees from land and space: tag design, implementation, and lessons learned from long-term study

    USGS Publications Warehouse

    Deutsch, C.J.; Bonde, R.K.; Reid, J.P.

    1998-01-01

    West Indian manatees (Trichechus manatus) were tracked along the Atlantic coast of Florida and Georgia (N = 83 manatees, n = 439 tag deployments, 1986-1996) and in eastern Puerto Rico (N = 8, n = 43, 1992-1996) using conventional and satellite-based radio-telemetry systems. A floating radio-tag, attached by a flexible tether to a padded belt around the base of the tail, enabled us to track manatees in saltwater environments. The tag incorporated VHF (very high frequency) and ultrasonic transmitters for field tracking and tag recovery, and an Argos satellite-monitored transmitter for remote tracking. We located each animal in the field about twice per week, received more than 60 000 good-quality Argos locations, and recovered tags in over 90% of deployments. The tag was designed to detach from the belt when entangled to prevent injury or drowning, and this often led to premature termination of tracking bouts. We had considerable success, however, in retagging belted manatees without recapture (97% of 392 retagging events). Most individuals were radio-tagged more than once (median = 3.0, maximum = 43) for a median total duration of 7.5 months (maximum = 6.8 yr). Data obtained through Argos have been valuable in addressing questions relating to long-distance movements, site fidelity, and identification of high-use areas. Fine-scale analyses of manatee habitat use and movements may require restricting the data set to the highest location quality or developing new analytical techniques to incorporate locational error. Field tracking provided useful ancillary data on life-history parameters, but sample sizes were small and survival estimates imprecise. Modification of the existing tag design to include Global Positioning System (GPS) functionality, with its finer spatial and temporal resolution, will offer new opportunities to address critical research and management problems facing this endangered species.

  17. Accurate tracking of high dynamic vehicles with translated GPS

    NASA Astrophysics Data System (ADS)

    Blankshain, Kenneth M.

    The GPS concept and the translator processing system (TPS) which were developed for accurate and cost-effective tracking of various types of high dynamic expendable vehicles are described. A technique used by the translator processing system (TPS) to accomplish very accurate high dynamic tracking is presented. Automatic frequency control and fast Fourier transform processes are combined to track 100 g acceleration and 100 g/s jerk with 1-sigma velocity measurement error less than 1 ft/sec.

  18. GPS-based tracking system for TOPEX orbit determination

    NASA Technical Reports Server (NTRS)

    Melbourne, W. G.

    1984-01-01

    A tracking system concept is discussed that is based on the utilization of the constellation of Navstar satellites in the Global Positioning System (GPS). The concept involves simultaneous and continuous metric tracking of the signals from all visible Navstar satellites by approximately six globally distributed ground terminals and by the TOPEX spacecraft at 1300-km altitude. Error studies indicate that this system could be capable of obtaining decimeter position accuracies and, most importantly, around 5 cm in the radial component which is key to exploiting the full accuracy potential of the altimetric measurements for ocean topography. Topics covered include: background of the GPS, the precision mode for utilization of the system, past JPL research for using the GPS in precision applications, the present tracking system concept for high accuracy satellite positioning, and results from a proof-of-concept demonstration.

  19. Fluorescent Nanodiamond: A Versatile Tool for Long-Term Cell Tracking, Super-Resolution Imaging, and Nanoscale Temperature Sensing.

    PubMed

    Hsiao, Wesley Wei-Wen; Hui, Yuen Yung; Tsai, Pei-Chang; Chang, Huan-Cheng

    2016-03-15

    Fluorescent nanodiamond (FND) has recently played a central role in fueling new discoveries in interdisciplinary fields spanning biology, chemistry, physics, and materials sciences. The nanoparticle is unique in that it contains a high density ensemble of negatively charged nitrogen-vacancy (NV(-)) centers as built-in fluorophores. The center possesses a number of outstanding optical and magnetic properties. First, NV(-) has an absorption maximum at ∼550 nm, and when exposed to green-orange light, it emits bright fluorescence at ∼700 nm with a lifetime of longer than 10 ns. These spectroscopic properties are little affected by surface modification but are distinctly different from those of cell autofluorescence and thus enable background-free imaging of FNDs in tissue sections. Such characteristics together with its excellent biocompatibility render FND ideal for long-term cell tracking applications, particularly in stem cell research. Next, as an artificial atom in the solid state, the NV(-) center is perfectly photostable, without photobleaching and blinking. Therefore, the NV-containing FND is suitable as a contrast agent for super-resolution imaging by stimulated emission depletion (STED). An improvement of the spatial resolution by 20-fold is readily achievable by using a high-power STED laser to deplete the NV(-) fluorescence. Such improvement is crucial in revealing the detailed structures of biological complexes and assemblies, including cellular organelles and subcellular compartments. Further enhancement of the resolution for live cell imaging is possible by manipulating the charge states of the NV centers. As the "brightest" member of the nanocarbon family, FND holds great promise and potential for bioimaging with unprecedented resolution and precision. Lastly, the NV(-) center in diamond is an atom-like quantum system with a total electron spin of 1. The ground states of the spins show a crystal field splitting of 2.87 GHz, separating the ms = 0 and

  20. When and where does mortality occur in migratory birds? Direct evidence from long-term satellite tracking of raptors.

    PubMed

    Klaassen, Raymond H G; Hake, Mikael; Strandberg, Roine; Koks, Ben J; Trierweiler, Christiane; Exo, Klaus-Michael; Bairlein, Franz; Alerstam, Thomas

    2014-01-01

    Information about when and where animals die is important to understand population regulation. In migratory animals, mortality might occur not only during the stationary periods (e.g. breeding and wintering) but also during the migration seasons. However, the relative importance of population limiting factors during different periods of the year remains poorly understood, and previous studies mainly relied on indirect evidence. Here, we provide direct evidence about when and where migrants die by identifying cases of confirmed and probable deaths in three species of long-distance migratory raptors tracked by satellite telemetry. We show that mortality rate was about six times higher during migration seasons than during stationary periods. However, total mortality was surprisingly similar between periods, which can be explained by the fact that risky migration periods are shorter than safer stationary periods. Nevertheless, more than half of the annual mortality occurred during migration. We also found spatiotemporal patterns in mortality: spring mortality occurred mainly in Africa in association with the crossing of the Sahara desert, while most mortality during autumn took place in Europe. Our results strongly suggest that events during the migration seasons have an important impact on the population dynamics of long-distance migrants. We speculate that mortality during spring migration may account for short-term annual variation in survival and population sizes, while mortality during autumn migration may be more important for long-term population regulation (through density-dependent effects). © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

  1. Transient Ischemic Attack Fast-track and Long-Term Stroke Risk: Role of Diffusion-Weighted Magnetic Resonance Imaging.

    PubMed

    Anticoli, Sabrina; Pezzella, Francesca Romana; Pozzessere, Claudio; Gallelli, Luca; Bravi, Maria Cristina; Caso, Valeria; Siniscalchi, Antonio

    2015-09-01

    fast-track had similar long-term risks of stroke. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  2. Impact of GPS tracking data of LEO satellites on global GPS solutions

    NASA Astrophysics Data System (ADS)

    Rothacher, M.; Svehla, D.

    Already at present quite a few Low Earth Orbiting (LEO) satellites (SAC-C, CHAMP, JASON-1, GRACE-1 and GRACE-2) are equipped with one or more GPS receivers for precise orbit determination or other applications (atmospheric sounding, gravity field recovery, . . . ). This trend will continue in the near future (e.g., with the GOCE and COSMIC missions) and we will soon have an entire "constellation" of LEO satellites tracked by GPS at our disposal. In this contribution we want to study the impact of LEO GPS measurements (from a single LEO satellite or from a LEO constellation) on global GPS solutions, where GPS satellite orbits and clocks, Earth rotation parameters (ERPs), station coordinates and troposphere zenith delays are determined simultaneously using the data of the global network of the International GPS Service (IGS). In order to assess the impact of the LEO GPS data on global IGS results, we have to perform a combined analysis of the space-borne and the ground-based GPS data. Such a combination may benefit on one hand from the differences between a ground station and a LEO, e.g., (1) the different tracking geometry (coverage of isolated geographical areas by LEOs, rapidly changing geometry, . . . ), (2) that LEOs connect all ground stations within 1-2 hours, (3) that baselines between LEO and ground stations may be longer than station-station baselines, (4) that no tropospheric delays have to be estimated for LEOs, and (5) that LEOs orbit the Earth within the ionosphere and may therefore contribute to global ionosphere models. On the other hand we have to deal with difficult aspects of precise orbit determination for the LEOs: only if we succeed to obtain very accurate dynamic or reduced-dynamic orbits for the LEOs, we will have a chance at all to improve the global GPS results. We present first results concerning the influence of LEO data on GPS orbits, ERPs, site coordinates, and troposphere zenith delays using both, variance-covariance analyses based on

  3. Usefulness of commercially available GPS data-loggers for tracking human movement and exposure to dengue virus.

    PubMed

    Vazquez-Prokopec, Gonzalo M; Stoddard, Steven T; Paz-Soldan, Valerie; Morrison, Amy C; Elder, John P; Kochel, Tadeusz J; Scott, Thomas W; Kitron, Uriel

    2009-11-30

    Our understanding of the effects of human movement on dengue virus spread remains limited in part due to the lack of precise tools to monitor the time-dependent location of individuals. We determined the utility of a new, commercially available, GPS data-logger for long-term tracking of human movements in Iquitos, Peru. We conducted a series of evaluations focused on GPS device attributes key to reliable use and accuracy. GPS observations from two participants were later compared with semi-structured interview data to assess the usefulness of GPS technology to track individual mobility patterns. Positional point and line accuracy were 4.4 and 10.3 m, respectively. GPS wearing mode increased spatial point error by 6.9 m. Units were worn on a neck-strap by a carpenter and a moto-taxi driver for 14-16 days. The application of a clustering algorithm (I-cluster) to the raw GPS positional data allowed the identification of locations visited by each participant together with the frequency and duration of each visit. The carpenter moved less and spent more time in more fixed locations than the moto-taxi driver, who visited more locations for a shorter period of time. GPS and participants' interviews concordantly identified 6 common locations, whereas GPS alone identified 4 locations and participants alone identified 10 locations. Most (80%) of the locations identified by participants alone were places reported as visited for less than 30 minutes. The present study demonstrates the feasibility of a novel, commercially available GPS data-logger for long-term tracking of humans and shows the potential of these units to quantify mobility patterns in relationship with dengue virus transmission risk in a tropical urban environment. Cost, battery life, size, programmability and ease of wear are unprecedented from previously tested units, proving the usefulness of GPS-dataloggers for linking movement of individuals and transmission risk of dengue virus and other infectious agents

  4. Usefulness of commercially available GPS data-loggers for tracking human movement and exposure to dengue virus

    PubMed Central

    2009-01-01

    Background Our understanding of the effects of human movement on dengue virus spread remains limited in part due to the lack of precise tools to monitor the time-dependent location of individuals. We determined the utility of a new, commercially available, GPS data-logger for long-term tracking of human movements in Iquitos, Peru. We conducted a series of evaluations focused on GPS device attributes key to reliable use and accuracy. GPS observations from two participants were later compared with semi-structured interview data to assess the usefulness of GPS technology to track individual mobility patterns. Results Positional point and line accuracy were 4.4 and 10.3 m, respectively. GPS wearing mode increased spatial point error by 6.9 m. Units were worn on a neck-strap by a carpenter and a moto-taxi driver for 14-16 days. The application of a clustering algorithm (I-cluster) to the raw GPS positional data allowed the identification of locations visited by each participant together with the frequency and duration of each visit. The carpenter moved less and spent more time in more fixed locations than the moto-taxi driver, who visited more locations for a shorter period of time. GPS and participants' interviews concordantly identified 6 common locations, whereas GPS alone identified 4 locations and participants alone identified 10 locations. Most (80%) of the locations identified by participants alone were places reported as visited for less than 30 minutes. Conclusion The present study demonstrates the feasibility of a novel, commercially available GPS data-logger for long-term tracking of humans and shows the potential of these units to quantify mobility patterns in relationship with dengue virus transmission risk in a tropical urban environment. Cost, battery life, size, programmability and ease of wear are unprecedented from previously tested units, proving the usefulness of GPS-dataloggers for linking movement of individuals and transmission risk of dengue

  5. A Cre-lox approach for transient transgene expression in neural precursor cells and long-term tracking of their progeny in vitro and in vivo

    PubMed Central

    Geoffroy, Cédric G; Raineteau, Olivier

    2007-01-01

    Background Neural precursor cells (NPCs) can be isolated from various regions of the postnatal central nervous system (CNS). Manipulation of gene expression in these cells offers a promising strategy to manipulate their fate both in vitro and in vivo. In this study, we developed a technique that allows the transient manipulation of single/multiple gene expression in NPCs in vitro, and the long-term tracking of their progeny both in vitro and in vivo. Results In order to combine the advantages of transient transfection with the long-term tracking of the transfected cells progeny, we developed a new approach based on the cre-lox technology. We first established a fast and reliable protocol to isolate and culture NPCs as monolayer, from the spinal cord of neonatal transgenic Rosa26-YFP cre-reporter mice. These cells could be reliably transfected with single/multiple plasmids by nucleofection. Nucleofection with mono- or bicistronic plasmids containing the Cre recombinase gene resulted in efficient recombination and the long-term expression of the YFP-reporter gene. The transient cre-expression was non-toxic for the transfected cells and did not alter their intrinsic properties. Finally, we demonstrated that cre-transfected cells could be transplanted into the adult brain, where they maintained YFP expression permitting long-term tracking of their migration and differentiation. Conclusion This approach allows single/multiple genes to be manipulated in NPCs, while at the same time allowing long-term tracking of the transfected cells progeny to be analyzed both in vitro and in vivo. PMID:17504531

  6. Fast-Acquisition/Weak-Signal-Tracking GPS Receiver for HEO

    NASA Technical Reports Server (NTRS)

    Wintemitz, Luke; Boegner, Greg; Sirotzky, Steve

    2004-01-01

    A report discusses the technical background and design of the Navigator Global Positioning System (GPS) receiver -- . a radiation-hardened receiver intended for use aboard spacecraft. Navigator is capable of weak signal acquisition and tracking as well as much faster acquisition of strong or weak signals with no a priori knowledge or external aiding. Weak-signal acquisition and tracking enables GPS use in high Earth orbits (HEO), and fast acquisition allows for the receiver to remain without power until needed in any orbit. Signal acquisition and signal tracking are, respectively, the processes of finding and demodulating a signal. Acquisition is the more computationally difficult process. Previous GPS receivers employ the method of sequentially searching the two-dimensional signal parameter space (code phase and Doppler). Navigator exploits properties of the Fourier transform in a massively parallel search for the GPS signal. This method results in far faster acquisition times [in the lab, 12 GPS satellites have been acquired with no a priori knowledge in a Low-Earth-Orbit (LEO) scenario in less than one second]. Modeling has shown that Navigator will be capable of acquiring signals down to 25 dB-Hz, appropriate for HEO missions. Navigator is built using the radiation-hardened ColdFire microprocessor and housing the most computationally intense functions in dedicated field-programmable gate arrays. The high performance of the algorithm and of the receiver as a whole are made possible by optimizing computational efficiency and carefully weighing tradeoffs among the sampling rate, data format, and data-path bit width.

  7. A GPS measurement system for precise satellite tracking and geodesy

    NASA Technical Reports Server (NTRS)

    Yunck, T. P.; Wu, S.-C.; Lichten, S. M.

    1985-01-01

    NASA is pursuing two key applications of differential positioning with the Global Positioning System (GPS): sub-decimeter tracking of earth satellites and few-centimeter determination of ground-fixed baselines. Key requirements of the two applications include the use of dual-frequency carrier phase data, multiple ground receivers to serve as reference points, simultaneous solution for use position and GPS orbits, and calibration of atmospheric delays using water vapor radiometers. Sub-decimeter tracking will be first demonstrated on the TOPEX oceanographic satellite to be launched in 1991. A GPS flight receiver together with at least six ground receivers will acquire delta range data from the GPS carriers for non-real-time analysis. Altitude accuracies of 5 to 10 cm are expected. For baseline measurements, efforts will be made to obtain precise differential pseudorange by resolving the cycle ambiguity in differential carrier phase. This could lead to accuracies of 2 or 3 cm over a few thousand kilometers. To achieve this, a high-performance receiver is being developed, along with improved calibration and data processing techniques. Demonstrations may begin in 1986.

  8. Development of an integrated obesity management waist belt system composed of calorie tracking and waist circumference measuring module for long term monitoring.

    PubMed

    Jang, Yongwon; Noh, Hyung Wook; Lee, I B; Song, Yoonseon; Jang, Won Ick; Lee, Sooyeul

    2011-01-01

    A waist belt type simple device was designed to monitor the individuals who are obese and want to maintain their consumed calories and waist circumference changes. Relatively long term monitoring with this device could help them maintain their health conditions. This devised system is composed of calorie tracking and waist circumference module. This study suggests feasible and meaningful results. If users' data are collected largely with this developed system, we can reveal the relationship between obesity and daily life pattern.

  9. Development of New Filter and Tracking Schemes for Weak GPS Signal Tracking

    NASA Astrophysics Data System (ADS)

    Kazemi, Pejman Lotfali

    Various emerging applications require location of users in challenging environments where typical GPS receivers suffer degraded performance or complete failure. Special algorithms and techniques are required to track weak GPS signals, where the signal is typically weaker by 10 to 40 dB compared to the nominal or line-of-sight signal strength. This thesis endeavours to propose solutions that can potentially offer performance improvements over conventional techniques. Optimum digital tracking filters for loops of first to fourth order, for rate only and phase and rate feedback NCO are derived. It is shown that, contrary to conventional methods, the loops remain stable for high B LT (the product of loop noise bandwidth and loop update interval) values and for both types of aforementioned NCOs. By using these filters, a significant improvement for high BLT can be achieved, allowing one to operate in ranges where previous methods cannot operate. As a result, stable loops with longer integration times (update interval) can be easily designed and the tracking sensitivity is improved accordingly. For the cases when external data aiding is not available, a decision feedback principle is used herein, in which the data bits are estimated through the tracking process itself. An enhanced digital phase locked loop with a frequency rate estimator is also developed. The NCO with phase rate and frequency rate feedback is introduced and based on this NCO and the transfer function of the frequency rate estimator, the tracking loop is optimized in order to minimize the phase noise variance. By utilizing this loop, the performance of low update rate loops in terms of phase mismatch and bit error rate can be improved. A multistage tracking scheme is also implemented to overcome the problem of tracking weak GPS signals in indoor environments. In this technique several tracking schemes are serially cascaded. It is shown that this technique combined with a developed optimum delay locked

  10. Modeling and performance analysis of GPS vector tracking algorithms

    NASA Astrophysics Data System (ADS)

    Lashley, Matthew

    This dissertation provides a detailed analysis of GPS vector tracking algorithms and the advantages they have over traditional receiver architectures. Standard GPS receivers use a decentralized architecture that separates the tasks of signal tracking and position/velocity estimation. Vector tracking algorithms combine the two tasks into a single algorithm. The signals from the various satellites are processed collectively through a Kalman filter. The advantages of vector tracking over traditional, scalar tracking methods are thoroughly investigated. A method for making a valid comparison between vector and scalar tracking loops is developed. This technique avoids the ambiguities encountered when attempting to make a valid comparison between tracking loops (which are characterized by noise bandwidths and loop order) and the Kalman filters (which are characterized by process and measurement noise covariance matrices) that are used by vector tracking algorithms. The improvement in performance offered by vector tracking is calculated in multiple different scenarios. Rule of thumb analysis techniques for scalar Frequency Lock Loops (FLL) are extended to the vector tracking case. The analysis tools provide a simple method for analyzing the performance of vector tracking loops. The analysis tools are verified using Monte Carlo simulations. Monte Carlo simulations are also used to study the effects of carrier to noise power density (C/N0) ratio estimation and the advantage offered by vector tracking over scalar tracking. The improvement from vector tracking ranges from 2.4 to 6.2 dB in various scenarios. The difference in the performance of the three vector tracking architectures is analyzed. The effects of using a federated architecture with and without information sharing between the receiver's channels are studied. A combination of covariance analysis and Monte Carlo simulation is used to analyze the performance of the three algorithms. The federated algorithm without

  11. A review of GPS-based tracking techniques for TDRS orbit determination

    NASA Technical Reports Server (NTRS)

    Haines, B. J.; Lichten, S. M.; Malla, R. P.; Wu, S.-C.

    1993-01-01

    This article evaluates two fundamentally different approaches to the Tracking and Data Relay Satellite (TDRS) orbit determination utilizing Global Positioning System (GPS) technology and GPS-related techniques. In the first, a GPS flight receiver is deployed on the TDRS. The TDRS ephemerides are determined using direct ranging to the GPS spacecraft, and no ground network is required. In the second approach, the TDRS's broadcast a suitable beacon signal, permitting the simultaneous tracking of GPS and Tracking and Data Relay Satellite System satellites by ground receivers. Both strategies can be designed to meet future operational requirements for TDRS-II orbit determination.

  12. Relation between strain dyssynchrony index determined by comprehensive assessment using speckle-tracking imaging and long-term outcome after cardiac resynchronization therapy for patients with heart failure.

    PubMed

    Tatsumi, Kazuhiro; Tanaka, Hidekazu; Matsumoto, Kensuke; Kaneko, Akihiro; Tsuji, Takayuki; Ryo, Keiko; Fukuda, Yuko; Norisada, Kazuko; Onishi, Tetsuari; Yoshida, Akihiro; Kawai, Hiroya; Hirata, Ken-Ichi

    2012-04-15

    Strain dyssynchrony index (SDI), which was a marker of dyssynchrony and residual myocardial contractility, can predict left ventricular reverse remodeling short-term after cardiac resynchronization therapy (CRT). We investigated SDI-predicted long-term outcome after CRT in patients with heart failure (HF). We studied 74 patients with HF who underwent CRT. SDI was calculated as the average difference between peak and end-systolic strain from 6 segments for radial and circumferential SDIs and 18 segments for longitudinal SDI using 2-dimensional speckle-tracking strain. Based on our previous findings, the predefined cutoff for significant dyssynchrony and residual myocardial contractility was a radial SDI ≥6.5%, a circumferential SDI ≥3.2%, and a longitudinal SDI ≥3.6%. The predefined principal outcome variable was the combined end point of death or hospitalization owing to deteriorating HF. Long-term follow-up after CRT was tracked over 4 years. The primary end point of prespecified events occurred in 14 patients (19%). An association with a favorable long-term outcome after CRT was observed in patients with significant radial, circumferential, and longitudinal SDIs (p <0.001, <0.005, and 0.010 vs patients without significant SDIs, respectively). Furthermore, cardiovascular event-free rate after CRT in patients with positivity of 3 for the 3 SDIs was 100% better than that in patients with positivity of 1 (52%, p <0.005) or 0 (31%, p <0.001) for the 3 SDIs. In conclusion, SDIs can successfully predict long-term outcome after CRT in patients with HF. Moreover, the approach combining the 3 types of SDI leads to a more accurate prediction than the use of individual parameters. These findings may have clinical implications in patients with CRT.

  13. Post-disposal orbital evolution of satellites and upper stages used by the GPS and GLONASS navigation constellations: The long-term impact on the Medium Earth Orbit environment

    NASA Astrophysics Data System (ADS)

    Pardini, Carmen; Anselmo, Luciano

    2012-08-01

    The long-term evolution and environmental impact in MEO of all the abandoned spacecraft and upper stages associated with the GPS and GLONASS navigation constellations were analyzed. The orbits of the disposed objects, as of 1 May 2011, were propagated for 200 years and snapshots of their evolving distribution were obtained, together with an estimation of the changing collision probability with the spacecraft of the operational navigation systems existing or planned in MEO, i.e., GLONASS, GPS, Beidou and Galileo. The probability that the abandoned objects considered will collide with the operational spacecraft of the navigation constellations is very low, even taking into account the intrinsic eccentricity instability of the disposal orbits. Assuming the present or envisaged configuration of the constellations in MEO, the probability of collision, integrated over 200 years, would be <1/300 with a GLONASS spacecraft, <1/15,000 with a GPS or Beidou spacecraft, and <1/250,000 with a Galileo spacecraft. The worst disposal strategy consists in abandoning satellites and upper stages close to the altitude of the operational constellation (GLONASS), while a re-orbiting a few hundred km away (GPS) is able to guarantee an effective long-term dilution of the collision risk, irrespective of the eccentricity instability due to geopotential and luni-solar perturbations. The disposal strategies applied so far to the GPS satellites should be able to guarantee for at least a few centuries a sustainable MEO environment free of collisions among intact objects. Consequently, there would be no need to adopt disposal schemes targeting also the optimal value of the eccentricity vector. However, it should be pointed out that the GPS disposal strategy was devised well in advance of the Beidou constellation announcement, so most of the abandoned satellites were re-orbited fairly close to the altitude of the new Chinese system. A new re-orbiting approach will be therefore needed in the future.

  14. Long-Term MR Cell Tracking of Neural Stem Cells Grafted in Immunocompetent Versus Immunodeficient Mice Reveals Distinct Differences in Contrast Between Live and Dead Cells

    PubMed Central

    Berman, Stacey Cromer; Galpoththawela, Chulani; Gilad, Assaf A.; Bulte, Jeff W. M.; Walczak, Piotr

    2011-01-01

    Neural stem cell (NSC)-based therapy is actively being pursued in preclinical and clinical disease models. Magnetic resonance imaging (MRI) cell tracking promises to optimize current cell transplantation paradigms, however, it is limited by dilution of contrast agent during cellular proliferation, transfer of label from dying cells to surrounding endogenous host cells, and/or biodegradation of the label. Here, we evaluated the applicability of magnetic resonance imaging for long-term tracking of transplanted neural stem cells labeled with superparamagnetic iron oxide and transfected with the bioluminescence reporter gene luciferase. Mouse neural stem cells were transplanted into immunodeficient, graft-accepting Rag2 mice or immunocompetent, graft-rejecting Balb/c mice. Hypointense voxel signals and bioluminescence were monitored over a period of 93 days. Unexpectedly, in mice that rejected the cells, the hypointense MR signal persisted throughout the entire time-course, whereas in the nonrejecting mice, the contrast cleared at a faster rate. In immunocompetent, graft-rejecting Balb/c mice, infiltrating leukocytes, and microglia were found surrounding dead cells and internalizing superparamagnetic iron oxide clusters. The present results indicate that live cell proliferation and associated label dilution may dominate contrast clearance as compared with cell death and subsequent transfer and retention of superparamagnetic iron oxide within phagocytes and brain interstitium. Thus, interpretation of signal changes during long-term MR cell tracking is complex and requires caution. PMID:20928883

  15. Tracking interspecies transmission and long-term evolution of an ancient retrovirus using the genomes of modern mammals.

    PubMed

    Diehl, William E; Patel, Nirali; Halm, Kate; Johnson, Welkin E

    2016-03-08

    Mammalian genomes typically contain hundreds of thousands of endogenous retroviruses (ERVs), derived from ancient retroviral infections. Using this molecular 'fossil' record, we reconstructed the natural history of a specific retrovirus lineage (ERV-Fc) that disseminated widely between ~33 and ~15 million years ago, corresponding to the Oligocene and early Miocene epochs. Intercontinental viral spread, numerous instances of interspecies transmission and emergence in hosts representing at least 11 mammalian orders, and a significant role for recombination in diversification of this viral lineage were also revealed. By reconstructing the canonical retroviral genes, we identified patterns of adaptation consistent with selection to maintain essential viral protein functions. Our results demonstrate the unique potential of the ERV fossil record for studying the processes of viral spread and emergence as they play out across macro-evolutionary timescales, such that looking back in time may prove insightful for predicting the long-term consequences of newly emerging viral infections.

  16. Using ionospheric scintillation indices to estimate GPS receiver tracking performance

    NASA Astrophysics Data System (ADS)

    Elmas, Zeynep G.; Aquino, Marcio; Dodson, Alan

    2010-05-01

    The Institute of Engineering Surveying and Space Geodesy (IESSG), at the University of Nottingham, has been involved with ionospheric scintillation research and its impact on users of Global Navigation Satellite Systems (GNSS) since 2001. The IESSG hosts a comprehensive archive of scintillation data recorded during the last high of the solar cycle (2001-2003) by four GSV4004 receivers (GPS Silicon Valley) in the UK and Norway, at geographic latitudes varying from 53N to 71N. The scintillation data that forms this ~3-year archive is given solely by the widely used scintillation indices S4 and σφ (in particular the latter's 60 second version). Aquino et al (2007) describe a strategy devised to enable the combination of these scintillation indices and the spectral parameters T (the spectral strength of the phase noise at 1 Hz) and p (the spectral slope), extracted from high-rate GPS phase and amplitude data, with state-of-the-art receiver tracking models in order to study receiver tracking performance under scintillation conditions. Strangeways (2009) later devised a method to calculate the scintillation parameters T and p over a range of Fresnel frequencies based only on the scintillation indices, i.e. when high rate data is not available, as in the case of the IESSG archive of 2001-2003. This paper shows initial investigations on the retrieval of the spectral parameters p and T from actual GPS scintillation indices recorded more recently in Trondheim (app. Lat 64N, Long 10E) on 23 April 2008. T and p values are estimated from S4 and σφ and compared with actual spectral parameters obtained from high rate data that are now being recorded. The paper then takes investigations a step further, by comparing the output of a state of the art tracking model when the estimated and actual spectral parameters are used as input, respectively. This paper gives an initial insight on the applicability of the method to mitigate the effects of the ionospheric scintillation on

  17. Orbit determination of the Sentinel satellites - preparations for GPS L2C-tracking

    NASA Astrophysics Data System (ADS)

    Peter, Heike; Fernández, Jaime; Fernández, Carlos; Féménias, Pierre

    2017-04-01

    presents the Copernicus POD Service in terms of operations and orbital accuracy achieved by the different orbit products of the different missions. The long-term evolution and progress of the service is presented and the impact and challenges following a future switch to L2C tracking are analysed.

  18. Magnetic Particle Imaging tracks the long-term fate of in vivo neural cell implants with high image contrast.

    PubMed

    Zheng, Bo; Vazin, Tandis; Goodwill, Patrick W; Conway, Anthony; Verma, Aradhana; Saritas, Emine Ulku; Schaffer, David; Conolly, Steven M

    2015-09-11

    We demonstrate that Magnetic Particle Imaging (MPI) enables monitoring of cellular grafts with high contrast, sensitivity, and quantitativeness. MPI directly detects the intense magnetization of iron-oxide tracers using low-frequency magnetic fields. MPI is safe, noninvasive and offers superb sensitivity, with great promise for clinical translation and quantitative single-cell tracking. Here we report the first MPI cell tracking study, showing 200-cell detection in vitro and in vivo monitoring of human neural graft clearance over 87 days in rat brain.

  19. Magnetic Particle Imaging tracks the long-term fate of in vivo neural cell implants with high image contrast

    PubMed Central

    Zheng, Bo; Vazin, Tandis; Goodwill, Patrick W.; Conway, Anthony; Verma, Aradhana; Ulku Saritas, Emine; Schaffer, David; Conolly, Steven M.

    2015-01-01

    We demonstrate that Magnetic Particle Imaging (MPI) enables monitoring of cellular grafts with high contrast, sensitivity, and quantitativeness. MPI directly detects the intense magnetization of iron-oxide tracers using low-frequency magnetic fields. MPI is safe, noninvasive and offers superb sensitivity, with great promise for clinical translation and quantitative single-cell tracking. Here we report the first MPI cell tracking study, showing 200-cell detection in vitro and in vivo monitoring of human neural graft clearance over 87 days in rat brain. PMID:26358296

  20. Towards a long-term Science Exploitation Plan for the Sea and Land Surface Temperature Radiometer on Sentinel-3 and the Along-Track Scanning Radiometers

    NASA Astrophysics Data System (ADS)

    Remedios, John J.; Llewellyn-Jones, David

    2014-05-01

    The Sea and Land Surface Temperature Radiometer (SLSTR) on Sentinel-3 is the latest satellite instrument in a series of dual-angle optical and thermal sensors, the Along-Track Scanning Radiometers (ATSRs). Operating on Sentinel-3, the SLSTR has a number of significant improvements compared to the original ATSRs including wider swaths for nadir and dual angles, emphasis on all surface temperature domains, dedicated fire channels and additional cloud channels. The SLSTR therefore provides some excellent opportunities to extend science undertaken with the ATSRs whilst also providing long-term data sets to investigate climate change. The European Space Agency, together with the Department of Energy and Climate Change, sponsored the production of an Exploitation Plan for the ATSRs. In the last year, this been extended to cover the SLSTR also. The plan enables UK and European member states to plan activities related to SLSTR in a long-term context. Covering climate change, oceanography, land surface, atmosphere and cryosphere science, particular attention is paid to the exploitation of long-term data sets. In the case of SLSTR, relevant products include sea, land, lake and ice surface temperatures; aerosols and clouds; fires and gas flares; land surface reflectances. In this presentation, the SLSTR and ATSR science Exploitation Plan will be outlined with emphasis on SLSTR science opportunities, on appropriate co-ordinating mechanisms and on example implementation plans. Particular attention will be paid to the challenges of linking ATSR records with SLSTR to provide consistent long-term data sets, and on the international context of such data sets. The exploitation plan approach to science may prove relevant and useful for other Sentinel instruments.

  1. Molecular tracking of Candida albicans in a neonatal intensive care unit: long-term colonizations versus catheter-related infections.

    PubMed Central

    Ruiz-Diez, B; Martinez, V; Alvarez, M; Rodriguez-Tudela, J L; Martinez-Suarez, J V

    1997-01-01

    Nosocomial neonatal candidiasis is a major problem in infants requiring intensive therapy. The subjects of this retrospective study were nine preterm infants admitted to the neonatal intensive care unit of the Hospital Central de Asturias between March 1993 and August 1994. The infants were infected with or colonized by Candida albicans. Five patients developed C. albicans bloodstream infections. A total of 36 isolates (including isolates from catheters and parenteral nutrition) were examined for molecular relatedness by PCR fingerprinting and restriction fragment length polymorphism (RFLP) analysis. The core sequence of phage M13 was used as a single primer in the PCR-based fingerprinting procedure, and RFLP analysis was performed with C. albicans-specific DNA probe 27A. Both techniques were evaluated with a panel of eight C. albicans reference strains, and each technique showed eight different patterns. With the 36 isolates from neonates, each technique enabled us to identify by PCR and RFLP analysis seven and six different patterns, respectively. The combination of these two methods (composite DNA type) identified eight different profiles. A strain with one of these profiles was present in three patients and in their respective catheters. Patients infected with or colonized by this isolate profile were clustered in time. Among the other patients, each patient was infected over time and at multiple anatomic sites with a C. albicans strain with a distinct DNA type. We conclude that C. albicans was most commonly producing long-term colonizations, although horizontal transmission probably due to catheters also occurred. PMID:9399489

  2. Long-term satellite tracking reveals variable seasonal migration strategies of basking sharks in the north-east Atlantic

    PubMed Central

    Doherty, P. D.; Baxter, J. M.; Gell, F. R.; Godley, B. J.; Graham, R. T.; Hall, G.; Hall, J.; Hawkes, L. A.; Henderson, S. M.; Johnson, L.; Speedie, C.; Witt, M. J.

    2017-01-01

    Animal migration is ubiquitous in nature with individuals within a population often exhibiting varying movement strategies. The basking shark (Cetorhinus maximus) is the world’s second largest fish species, however, a comprehensive understanding of their long-term wider-ranging movements in the north-east Atlantic is currently lacking. Seventy satellite tags were deployed on basking sharks over four years (2012–2015) off the west coast of Scotland and the Isle of Man. Data from 28 satellite tags with attachment durations of over 165 days reveal post-summer ranging behaviours. Tagged sharks moved a median minimum straight-line distance of 3,633 km; achieving median displacement of 1,057 km from tagging locations. Tagged individuals exhibited one of three migration behaviours: remaining in waters of UK, Ireland and the Faroe Islands; migrating south to the Bay of Biscay or moving further south to waters off the Iberian Peninsula, and North Africa. Sharks used both continental shelf areas and oceanic habitats, primarily in the upper 50–200 m of the water column, spanning nine geo-political zones and the High Seas, demonstrating the need for multi-national cooperation in the management of this species across its range. PMID:28216646

  3. Tracking interspecies transmission and long-term evolution of an ancient retrovirus using the genomes of modern mammals

    PubMed Central

    Diehl, William E; Patel, Nirali; Halm, Kate; Johnson, Welkin E

    2016-01-01

    Mammalian genomes typically contain hundreds of thousands of endogenous retroviruses (ERVs), derived from ancient retroviral infections. Using this molecular 'fossil' record, we reconstructed the natural history of a specific retrovirus lineage (ERV-Fc) that disseminated widely between ~33 and ~15 million years ago, corresponding to the Oligocene and early Miocene epochs. Intercontinental viral spread, numerous instances of interspecies transmission and emergence in hosts representing at least 11 mammalian orders, and a significant role for recombination in diversification of this viral lineage were also revealed. By reconstructing the canonical retroviral genes, we identified patterns of adaptation consistent with selection to maintain essential viral protein functions. Our results demonstrate the unique potential of the ERV fossil record for studying the processes of viral spread and emergence as they play out across macro-evolutionary timescales, such that looking back in time may prove insightful for predicting the long-term consequences of newly emerging viral infections. DOI: http://dx.doi.org/10.7554/eLife.12704.001 PMID:26952212

  4. Long-term satellite tracking reveals variable seasonal migration strategies of basking sharks in the north-east Atlantic.

    PubMed

    Doherty, P D; Baxter, J M; Gell, F R; Godley, B J; Graham, R T; Hall, G; Hall, J; Hawkes, L A; Henderson, S M; Johnson, L; Speedie, C; Witt, M J

    2017-02-20

    Animal migration is ubiquitous in nature with individuals within a population often exhibiting varying movement strategies. The basking shark (Cetorhinus maximus) is the world's second largest fish species, however, a comprehensive understanding of their long-term wider-ranging movements in the north-east Atlantic is currently lacking. Seventy satellite tags were deployed on basking sharks over four years (2012-2015) off the west coast of Scotland and the Isle of Man. Data from 28 satellite tags with attachment durations of over 165 days reveal post-summer ranging behaviours. Tagged sharks moved a median minimum straight-line distance of 3,633 km; achieving median displacement of 1,057 km from tagging locations. Tagged individuals exhibited one of three migration behaviours: remaining in waters of UK, Ireland and the Faroe Islands; migrating south to the Bay of Biscay or moving further south to waters off the Iberian Peninsula, and North Africa. Sharks used both continental shelf areas and oceanic habitats, primarily in the upper 50-200 m of the water column, spanning nine geo-political zones and the High Seas, demonstrating the need for multi-national cooperation in the management of this species across its range.

  5. Head Tracking for 3D Audio Using a GPS-Aided MEMS IMU

    DTIC Science & Technology

    2005-03-01

    Aircraft, Directional Signals, GPS/INS Fusion , GPS/INS Integration, Head Tracking Systems, IMU (Inertial Measurement Unit), Inertial Sensors, MEMS...HEAD TRACKING FOR 3D AUDIO USING A GPS-AIDED MEMS IMU THESIS Jacque M. Joffrion, Captain, USAF AFIT/GE/ENG/05-09 DEPARTMENT OF THE AIR FORCE AIR...the United States Government. AFIT/GE/ENG/05-09 HEAD TRACKING FOR 3D AUDIO USING A GPS-AIDED MEMS IMU THESIS Presented to the Faculty of the Department

  6. Long-term 15N tracking from biological N fixation across different plant and humus components of the boreal forest

    NASA Astrophysics Data System (ADS)

    Arroniz-Crespo, Maria; Jones, David L.; Zackrisson, Olle; Nilsson, Marie-Charlotte; DeLuca, Thomas H.

    2014-05-01

    Biological N2 fixation by cyanobacteria associated with feather mosses is an important cog in the nitrogen (N) cycle of boreal forests; still, our understanding of the turnover and fate of N fixed by this association remains greatly incomplete. The 15N signature of plants and soil serves as a powerful tool to explore N dynamics in forest ecosystems. In particular, in the present study we aimed to investigate the contribution of N2 fixation to δ15N signatures of plants and humus component of the boreal forest. Here we present results from a long-term (7 years) tacking of labelled 15N2 across the humus layer, seedlings of the tree species Pinus sylvestris, two common dwarf shrub species (Empetrum hermaphroditum and Vaccinium vitis-idaea) and the feather moss Pleurozium schreibery. The enriched experiment was conducted in 2005 in a natural boreal forest in northern Sweden. Two different treatments (10% 15N2 headspace enrichment and control) were setup in nine different plots (0.5 x 0.5 m) within the forest. We observed a significant reduction of δ15N signature of the 15N-enriched moss that could be explained by a growth dilution effect. Nevertheless, after 5 years since 15N2 enrichment some of the label 15N was still detected on the moss and in particular in the dead tissue. We could not detect a clear transfer of the labelled 15N2 from the moss-cyanobacteria system to other components of the ecosystem. However, we found consistence relationship through time between increments of δ15N signature of some of the forest components in plots which exhibited higher N fixation rates in the moss. In particular, changes in natural abundance δ15N that could be associated with N fixation were more apparent in the humus layer, the dwarf shrub Vaccinium vitis-idaea and the pine seedlings when comparing across plots and years.

  7. Multiple Single-Unit Long-Term Tracking on Organotypic Hippocampal Slices Using High-Density Microelectrode Arrays

    PubMed Central

    Gong, Wei; Senčar, Jure; Bakkum, Douglas J.; Jäckel, David; Obien, Marie Engelene J.; Radivojevic, Milos; Hierlemann, Andreas R.

    2016-01-01

    A novel system to cultivate and record from organotypic brain slices directly on high-density microelectrode arrays (HD-MEA) was developed. This system allows for continuous recording of electrical activity of specific individual neurons at high spatial resolution while monitoring at the same time, neuronal network activity. For the first time, the electrical activity patterns of single neurons and the corresponding neuronal network in an organotypic hippocampal slice culture were studied during several consecutive weeks at daily intervals. An unsupervised iterative spike-sorting algorithm, based on PCA and k-means clustering, was developed to assign the activities to the single units. Spike-triggered average extracellular waveforms of an action potential recorded across neighboring electrodes, termed “footprints” of single-units were generated and tracked over weeks. The developed system offers the potential to study chronic impacts of drugs or genetic modifications on individual neurons in slice preparations over extended times. PMID:27920665

  8. [(89)Zr]oxinate4 for long-term in vivo cell tracking by positron emission tomography.

    PubMed

    Charoenphun, Putthiporn; Meszaros, Levente K; Chuamsaamarkkee, Krisanat; Sharif-Paghaleh, Ehsan; Ballinger, James R; Ferris, Trevor J; Went, Michael J; Mullen, Gregory E D; Blower, Philip J

    2015-02-01

    (111)In (typically as [(111)In]oxinate3) is a gold standard radiolabel for cell tracking in humans by scintigraphy. A long half-life positron-emitting radiolabel to serve the same purpose using positron emission tomography (PET) has long been sought. We aimed to develop an (89)Zr PET tracer for cell labelling and compare it with [(111)In]oxinate3 single photon emission computed tomography (SPECT). [(89)Zr]Oxinate4 was synthesised and its uptake and efflux were measured in vitro in three cell lines and in human leukocytes. The in vivo biodistribution of eGFP-5T33 murine myeloma cells labelled using [(89)Zr]oxinate4 or [(111)In]oxinate3 was monitored for up to 14 days. (89)Zr retention by living radiolabelled eGFP-positive cells in vivo was monitored by FACS sorting of liver, spleen and bone marrow cells followed by gamma counting. Zr labelling was effective in all cell types with yields comparable with (111)In labelling. Retention of (89)Zr in cells in vitro after 24 h was significantly better (range 71 to >90%) than (111)In (43-52%). eGFP-5T33 cells in vivo showed the same early biodistribution whether labelled with (111)In or (89)Zr (initial pulmonary accumulation followed by migration to liver, spleen and bone marrow), but later translocation of radioactivity to kidneys was much greater for (111)In. In liver, spleen and bone marrow at least 92% of (89)Zr remained associated with eGFP-positive cells after 7 days in vivo. [(89)Zr]Oxinate4 offers a potential solution to the emerging need for a long half-life PET tracer for cell tracking in vivo and deserves further evaluation of its effects on survival and behaviour of different cell types.

  9. High-resolution positional tracking for long-term analysis of Drosophila sleep and locomotion using the "tracker" program.

    PubMed

    Donelson, Nathan C; Donelson, Nathan; Kim, Eugene Z; Slawson, Justin B; Vecsey, Christopher G; Huber, Robert; Griffith, Leslie C

    2012-01-01

    Drosophila melanogaster has been used for decades in the study of circadian behavior, and more recently has become a popular model for the study of sleep. The classic method for monitoring fly activity involves counting the number of infrared beam crosses in individual small glass tubes. Incident recording methods such as this can measure gross locomotor activity, but they are unable to provide details about where the fly is located in space and do not detect small movements (i.e. anything less than half the enclosure size), which could lead to an overestimation of sleep and an inaccurate report of the behavior of the fly. This is especially problematic if the fly is awake, but is not moving distances that span the enclosure. Similarly, locomotor deficiencies could be incorrectly classified as sleep phenotypes. To address these issues, we have developed a locomotor tracking technique (the "Tracker" program) that records the exact location of a fly in real time. This allows for the detection of very small movements at any location within the tube. In addition to circadian locomotor activity, we are able to collect other information, such as distance, speed, food proximity, place preference, and multiple additional parameters that relate to sleep structure. Direct comparisons of incident recording and our motion tracking application using wild type and locomotor-deficient (CASK-β null) flies show that the increased temporal resolution in the data from the Tracker program can greatly affect the interpretation of the state of the fly. This is especially evident when a particular condition or genotype has strong effects on the behavior, and can provide a wealth of information previously unavailable to the investigator. The interaction of sleep with other behaviors can also be assessed directly in many cases with this method.

  10. A Generic Receiver Tracking Model for GPS Ionospheric Amplitude Scintillation

    NASA Astrophysics Data System (ADS)

    Paula, E. R.; Moraes, A. D.; Perrella, W. J.; Galera Monico, J. F.

    2012-12-01

    Ionospheric scintillations result in rapid variations in phase and amplitude of the radio signal, which propagates through the ionosphere. Depending on the temporal and spatial situation, the scintillation can represent a problem in the availability and precision of the Global Navigation Satellite Systems (GNSS). Scintillations affect the receiver performance, specially the tracking loop level. Depending on the scintillation level, the receiver might increase the measurement errors or even can lead to a loss of lock of the carrier and code loops. In extreme cases, the scintillation can result in full disrupting of the receiver. In this work we introduce a generic model to evaluate the effects of ionospheric amplitude scintillation on GPS receiver tracking loops. This model is based on α-μ distribution, which can be seen as a generalized fading model, that includes a variety of distributions such as Gamma, Nakagami-m, Exponential, Weibull, one-sided Gaussian and Rayleigh. Differently from the model based only on Nakagami-m, this one is not limited to S4< 0,71 which allows using it to predict amplitude scintillation effects for stronger scenarios. The estimation of α-μ coefficients, the empirical parameterization based on field measurements and the typical values estimated based on observations made during the last solar maximum are presented and discussed.

  11. Long-Term Care

    MedlinePlus

    ... this page please turn Javascript on. Long-Term Care What Is Long-Term Care? Long-term care involves a variety of services ... the Escape (Esc) button on your keyboard.) Most Care Provided at Home Long-term care is provided ...

  12. Long-term tracking of hepatitis B viral load and the relationship with risk for hepatocellular carcinoma in men.

    PubMed

    Wu, Chih-Feng; Yu, Ming-Whei; Lin, Chih-Lin; Liu, Chun-Jen; Shih, Wei-Liang; Tsai, Keh-Sung; Chen, Chien-Jen

    2008-01-01

    Little is known about the longitudinal course of hepatitis B virus (HBV) load and its relationship with the development of hepatocellular carcinoma (HCC). We conducted a case-cohort study nested within a cohort of 2874 HBV surface antigen-positive male Taiwanese government employees aged 30 years or older. HBV genotype and DNA levels (i.e. viral load) were tested using polymerase chain reaction-based assays on plasma samples from 112 cases and 1031 non-cases. Prediagnostic plasma levels of HBV DNA were measured in multiple samples collected from each man (total 7706 samples), taken over periods of up to 16 years before diagnosis. Baseline viral load influenced HBV genotype-specific HCC risks and predicted the persistence of high viral load (>/=4.39 log copies/ml) that can cause HCC. Moderate to high tracking of viral load was observed within 9 years. Hepatitis B e antigen (P < 0.0001), genotype C HBV infection (P = 0.0369) and longitudinal alanine aminotransferase (ALT) elevation (defined as ALT abnormality in >/=50% of the visits) (P = 0.0005) were positively related to longer duration of persistence for high viral load. After multivariate adjustment, HBV genotype C [odds ratio (OR) = 5.97, 95% confidence interval (CI) = 3.44-10.34], high viral load detected at >/=50% of the visits (compared with sustained low viral load: OR = 5.04, 95% CI = 2.31-11.00) and longitudinal ALT elevation (compared with sustained normal ALT levels: OR = 2.84, 95% CI = 1.46-5.51) accounted for 43.5, 57.2 and 24.9% of HCCs, respectively. The results suggest that maintenance of viral load <4.39 log copies/ml was associated with sustained normalization of ALT levels and decreased risk of HCC.

  13. Hindered submicron mobility and long-term storage of presynaptic dense-core granules revealed by single-particle tracking.

    PubMed

    Scalettar, B A; Jacobs, C; Fulwiler, A; Prahl, L; Simon, A; Hilken, L; Lochner, J E

    2012-09-01

    Dense-core granules (DCGs) are organelles found in neuroendocrine cells and neurons that house, transport, and release a number of important peptides and proteins. In neurons, DCG cargo can include the secreted neuromodulatory proteins tissue plasminogen activator (tPA) and/or brain-derived neurotrophic factor (BDNF), which play a key role in modulating synaptic efficacy in the hippocampus. This function has spurred interest in DCGs that localize to synaptic contacts between hippocampal neurons, and several studies recently have established that DCGs localize to, and undergo regulated exocytosis from, postsynaptic sites. To complement this work, we have studied presynaptically localized DCGs in hippocampal neurons, which are much more poorly understood than their postsynaptic analogs. Moreover, to enhance relevance, we visualized DCGs via fluorescence labeling of exogenous and endogenous tPA and BDNF. Using single-particle tracking, we determined trajectories of more than 150 presynaptically localized DCGs. These trajectories reveal that mobility of DCGs in presynaptic boutons is highly hindered and that storage is long-lived. We also computed mean-squared displacement curves, which can be used to elucidate mechanisms of transport. Over shorter time windows, most curves are linear, demonstrating that DCG transport in boutons is driven predominantly by diffusion. The remaining curves plateau with time, consistent with motion constrained by a submicron-sized corral. These results have relevance to recent models of presynaptic organization and to recent hypotheses about DCG cargo function. The results also provide estimates for transit times to the presynaptic plasma membrane that are consistent with measured times for onset of neurotrophin release from synaptically localized DCGs. Copyright © 2011 Wiley Periodicals, Inc.

  14. Hindered submicron mobility and long-term storage of presynaptic dense-core granules revealed by single-particle tracking

    PubMed Central

    Scalettar, B. A.; Jacobs, C.; Fulwiler, A.; Prahl, L.; Simon, A.; Hilken, L.; Lochner, J. E.

    2012-01-01

    Dense-core granules (DCGs) are organelles found in neuroendocrine cells and neurons that house, transport, and release a number of important peptides and proteins. In neurons, DCG cargo can include the secreted neuromodulatory proteins tissue plasminogen activator (tPA) and/or brain-derived neurotrophic factor (BDNF), which play a key role in modulating synaptic efficacy in the hippocampus. This function has spurred interest in DCGs that localize to synaptic contacts between hippocampal neurons, and several studies recently have established that DCGs localize to, and undergo regulated exocytosis from, postsynaptic sites. To complement this work, we have studied presynaptically-localized DCGs in hippocampal neurons, which are much more poorly understood than their postsynaptic analogs. Moreover, to enhance relevance, we visualized DCGs via fluorescence labeling of exogenous and endogenous tPA and BDNF. Using single-particle tracking, we determined trajectories of more than 150 presynaptically-localized DCGs. These trajectories reveal that mobility of DCGs in presynaptic boutons is highly hindered and that storage is long-lived. We also computed mean-squared displacement curves, which can be used to elucidate mechanisms of transport. Over shorter time windows, most curves are linear, demonstrating that DCG transport in boutons is driven predominantly by diffusion. The remaining curves plateau with time, consistent with motion constrained by a submicron-sized corral. These results have relevance to recent models of presynaptic organization and to recent hypotheses about DCG cargo function. The results also provide estimates for transit times to the presynaptic plasma membrane that are consistent with measured times for onset of neurotrophin release from synaptically-localized DCGs. PMID:21976424

  15. The Maximum Compaction Depth of the Aquifers in the Houston-Galveston Area: a result from long-term GPS and extensometer observations

    NASA Astrophysics Data System (ADS)

    Yu, J.; Wang, G.; Kearns, T.; Yang, L.

    2014-12-01

    This study investigated the recent subsidence observed at different depths in the Houston-Galveston area. The subsidence was recorded by using 13 borehole extensometers and 76 GPS antennas. Four of the GPS antennas are mounted on the deep-anchored (549, 591, 661 and 936 m below the land surface) inner pipes of borehole extensometers. They are located at approximately the same depth as the bottom of Evangeline aquifer. There are two pairs of closely-spaced ( about 100 m) extensometers. They were completed at different depths and show the variation of compaction rate in depth. We conclude that recent subsidence (1993-2012) in the Houston-Galveston area was dominated by the compaction of sediments within 600 m below the land surface. Deep-anchored GPS data shows stable vertical movement indicating no measurable compaction at the depth of the Jasper aquifer or within deeper strata. Depending on the location of specific sites, the compaction could occur from a depth as shallow as that within the Chicot aquifer to the maximum depth at the middle of the Evangeline aquifer.

  16. Improvements in Dynamic GPS Positions Using Track Averaging

    DTIC Science & Technology

    1999-08-01

    Global Positioning System ( GPS ), Precise Positioning System (PPS) solution under dynamic...SUBJECT TERMS 15. NUMBER OF GPS , Global Positioning System , Dynamic Positioning PAGES 31 16. PRICE CODE 17. SECURITY CLASSIFICATION 18. SECURITY... Global Positioning System ( GPS ), Precise Positioning System (PPS) solution under dynamic conditions through averaging is investigated. Static

  17. GPS snow-depth meter using geometry-free linear combination: Long-term comparison with conventional snow-depth meter

    NASA Astrophysics Data System (ADS)

    Ozeki, M.; Heki, K.

    2010-12-01

    Multipath is the interference between direct and reflected waves from GPS satellites, and has been utilized to measure physical status of the ground surface as a reflector, e.g. soil moisture (Larson et al.,2008), snow depth (Larson et al.,2009), and vegetation (Small et al.,2010). The past studies used signal-to-noise ratio (SNR) to measure amplitudes and phases of such multipath. Here we report a method to measure snow depth using the ionospheric linear combination (often called L4), the simple difference between L1 and L2. L4 is geometry-free because it does not depend on coordinates of GPS sites and satellites, or atmospheric delays. As the GPS satellite moves in the sky, elevation changes, and L1/L2 (and L4 also) phases of reflected waves also change in particular periods. Such multipath-origin phase fluctuation shows large amplitudes when the satellite is low. The fluctuation periods depend on the antenna height, i.e. an antenna with smaller height shows a longer period (because the change of excess path length gets slower). Thus multipath period can be used to constrain the depth of snow, which causes apparent reduction in antenna height. In this study, we used data at a GEONET site 020877 in Shinshinotsu, northeast of Sapporo, from January to April in 2009. During this period, this antenna stood in an open ground, and we could analyze multipath signals of multiple satellites. We used data over two hour’s period before satellites sank or after they rose, and the estimated snow depth represents average over a circle with diameter of ~100 m. Observing time window was shifted forward four minutes every day, to keep the direction of satellite same. We analyzed the spectrum of the observed short-period changes of L4. They usually have two frequency peaks corresponding to L1 and L2 multipath. The L2 multipath frequency is ~4 mHz and this corresponds to the snow-free GPS antenna height of 5 meters. The frequency becomes lower as snow pack develops in winter, and

  18. Geodetic observations at Bezymianny Volcano, Kamchatka: The eruptions from 2005-2010 and long-term, long-wavelength subsidence as seen by the PIRE GPS network

    NASA Astrophysics Data System (ADS)

    Grapenthin, R.; Freymueller, J. T.; Serovetnikov, S. S.; Titkov, N.

    2012-04-01

    Bezymianny Volcano in Kamchatka reactivated after a roughly 1000 year hiatus in 1956 with an eruption that culminated into a directed blast due to a flank collapse. About 0.6 km3 of material were removed from the edifice. Today, eruptive activity occurs roughly every 6 months with a violent explosion lasting for 2 - 20 minutes that creates lava flows and pyroclastic flows. Here, we present the first detailed geodetic study focusing on Bezymianny Volcano in the context of a multi-disciplinary study from 2005-2010 that includes seismology, geology and volcanic gases. In 2005 the volcano was instrumented with an array of 6 campaign and 8 continuous GPS stations, none of which are telemetered. The campaign sites have been measured during annual summer fieldwork during which we also recovered data of the continuous sites. The first eruption recorded by a partial continuous GPS network was the December 24, 2006, event. Between then and the last data recovery in summer of 2010 six additional eruptions occurred. We analyze the data in the International Terrestrial Reference Frame (ITRF 2008) using the GIPSY/OASIS II software and find a relatively uniform network wide subsidence of about 7-9 mm/yr for the observation period from 2005 to 2010. This could be induced by continuous depressurization of a deeply seated magma reservoir, likely beneath Kluichevskoy volcano to the north of Bezymianny. We explore other possible sources such as regional surface loading due to deposition of eruptive products in this very productive volcanic region. Surface load effects could be induced by the new dome growing inside Bezymianny's horseshoe shaped crater and other material emplaced during the regular eruptions. Loading effects due to the young Kliuchevskoy volcano, the tallest volcano in Asia, are also considered. Analysis of daily averages of displacements around times of eruptions shows little to no inflation or deflation signal at distances as close as 1.5 km from the edifice related

  19. 82 FR 18736 - Impact of Long Term Evolution Signals on Global Positioning System Receivers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2017-04-21

    ... Long Term Evolution Signals on Global Positioning System Receivers AGENCY: National Institute of... project ``Impact of Long Term Evolution (LTE) signals on Global Positioning System (GPS) Devices''. At...

  20. GPS tracking for mapping seabird mortality induced by light pollution

    PubMed Central

    Rodríguez, Airam; Rodríguez, Beneharo; Negro, Juan J.

    2015-01-01

    Light pollution and its consequences on ecosystems are increasing worldwide. Knowledge on the threshold levels of light pollution at which significant ecological impacts emerge and the size of dark refuges to maintain natural nocturnal processes is crucial to mitigate its negative consequences. Seabird fledglings are attracted by artificial lights when they leave their nest at night, causing high mortality. We used GPS data-loggers to track the flights of Cory’s shearwater Calonectris diomedea fledglings from nest-burrows to ground, and to evaluate the light pollution levels of overflown areas on Tenerife, Canary Islands, using nocturnal, high-resolution satellite imagery. Birds were grounded at locations closer than 16 km from colonies in their maiden flights, and 50% were rescued within a 3 km radius from the nest-site. Most birds left the nests in the first three hours after sunset. Rescue locations showed radiance values greater than colonies, and flight distance was positively related to light pollution levels. Breeding habitat alteration by light pollution was more severe for inland colonies. We provide scientific-based information to manage dark refuges facilitating that fledglings from inland colonies reach the sea successfully. We also offer methodological approaches useful for other critically threatened petrel species grounded by light pollution. PMID:26035530

  1. GPS tracking for mapping seabird mortality induced by light pollution.

    PubMed

    Rodríguez, Airam; Rodríguez, Beneharo; Negro, Juan J

    2015-06-02

    Light pollution and its consequences on ecosystems are increasing worldwide. Knowledge on the threshold levels of light pollution at which significant ecological impacts emerge and the size of dark refuges to maintain natural nocturnal processes is crucial to mitigate its negative consequences. Seabird fledglings are attracted by artificial lights when they leave their nest at night, causing high mortality. We used GPS data-loggers to track the flights of Cory's shearwater Calonectris diomedea fledglings from nest-burrows to ground, and to evaluate the light pollution levels of overflown areas on Tenerife, Canary Islands, using nocturnal, high-resolution satellite imagery. Birds were grounded at locations closer than 16 km from colonies in their maiden flights, and 50% were rescued within a 3 km radius from the nest-site. Most birds left the nests in the first three hours after sunset. Rescue locations showed radiance values greater than colonies, and flight distance was positively related to light pollution levels. Breeding habitat alteration by light pollution was more severe for inland colonies. We provide scientific-based information to manage dark refuges facilitating that fledglings from inland colonies reach the sea successfully. We also offer methodological approaches useful for other critically threatened petrel species grounded by light pollution.

  2. Chondrocyte gene expression is affected by very small iron oxide particles-labeling in long-term in vitro MRI tracking.

    PubMed

    Foldager, Casper Bindzus; Pedersen, Michael; Ringgaard, Steffen; Bünger, Cody; Lind, Martin

    2011-03-01

    To investigate the effect and dose response of very small iron oxide particles (VSOP) labeling of human chondrocytes for long-term in vitro MRI tracking. Chondrocytes were isolated from cartilage biopsies from four patients. The cells for the dose-response study were labeled with 25, 50, or 100 μg/mL VSOP. Quantitative gene expression and cellular proliferation were compared with unlabeled controls at day 1, 3, and 7. The cells suited for MRI tracking were labeled with 50 μg/mL VSOP and embedded in alginate beads, followed by MRI (using T2-weighted sequences) at day 0, 1, 3, 7, 14, 21, 28, and histology was performed at each time-point. Histology revealed that VSOP particles were intracellularly confined at all time-points, whereas no extracellular VSOPs were observed. A mean reduction in T2-value of 25.1 ms (±SD 3.5 ms) was found on T2-maps. The chondrocyte-specific genes aggrecan, collagen type 2, and sox9 were all affected by labeling, the two latter in a dose-dependent manner. VSOPs had no effect on proliferation. VSOP labeling of chondrocytes affected gene expression but not proliferation. The labeled chondrocytes could be recognized by MRI for 4 weeks without significant changes in the T2 relaxation time. Copyright © 2011 Wiley-Liss, Inc.

  3. Superparamagnetic Iron Oxide Nanoparticles Function as a Long-Term, Multi-Modal Imaging Label for Non-Invasive Tracking of Implanted Progenitor Cells

    PubMed Central

    Pacak, Christina A.; Hammer, Peter E.; MacKay, Allison A.; Dowd, Rory P.; Wang, Kai-Roy; Masuzawa, Akihiro; Sill, Bjoern; McCully, James D.; Cowan, Douglas B.

    2014-01-01

    The purpose of this study was to determine the ability of superparamagnetic iron oxide (SPIO) nanoparticles to function as a long-term tracking label for multi-modal imaging of implanted engineered tissues containing muscle-derived progenitor cells using magnetic resonance imaging (MRI) and X-ray micro-computed tomography (μCT). SPIO-labeled primary myoblasts were embedded in fibrin sealant and imaged to obtain intensity data by MRI or radio-opacity information by μCT. Each imaging modality displayed a detection gradient that matched increasing SPIO concentrations. Labeled cells were then incorporated in fibrin sealant, injected into the atrioventricular groove of rat hearts, and imaged in vivo and ex vivo for up to 1 year. Transplanted cells were identified in intact animals and isolated hearts using both imaging modalities. MRI was better able to detect minuscule amounts of SPIO nanoparticles, while μCT more precisely identified the location of heavily-labeled cells. Histological analyses confirmed that iron oxide particles were confined to viable, skeletal muscle-derived cells in the implant at the expected location based on MRI and μCT. These analyses showed no evidence of phagocytosis of labeled cells by macrophages or release of nanoparticles from transplanted cells. In conclusion, we established that SPIO nanoparticles function as a sensitive and specific long-term label for MRI and μCT, respectively. Our findings will enable investigators interested in regenerative therapies to non-invasively and serially acquire complementary, high-resolution images of transplanted cells for one year using a single label. PMID:25250622

  4. Developing a protocol for long-term population monitoring and habitat projections for a climate-sensitive sentinel species to track ecosystem change and species range shifts

    NASA Astrophysics Data System (ADS)

    Beers, A.

    2016-12-01

    As a response to ongoing climate change, many species have started to shift their ranges poleward and toward higher elevations and mountain environments are predicted to experience especially rapid climatic changes. Because of this, there is likely a greater risk of habitat loss and local extinctions for species at high elevations compared to species at lower elevations. Among those potentially threatened habitat specialists is the American pika (Ochotona princeps), a climate sensitive indicator of climate change effects which may already be experiencing climate driven extirpations. Pikas are considered sentinels, indicators of greater ecosystem change. Changes in their distribution speaks to changes in availability of resources they require and shifts in the environment. Pika presence is closely tied to sub-surface ice features that act as a temperature buffer and water source. Those sub-surface ice features are critical in water cycling and long-term water storage and drive downstream hydrological and ecological processes. Understanding how this species responds to climate change therefore provides a model to inform landscape level conservation and management decisions. Pikas may be particularly vulnerable in parts of Colorado, including Rocky Mountain National Park (ROMO) and the Niwot Ridge LTER (NWT), where they may face population collapse as habitat suitability and connectivity both decline in response to various possible climate change scenarios, in large part because of cold stress and declining functional connectivity. Because of their potential role as an ecosystem indicator, their risk for decline, and how limitations to their survival likely vary across their range, management groups can use place based models of habitat suitability for pikas or other sentinel species in designing long term monitoring protocols to detect ecosystem responses to climate change. In this project we used remotely sensed data, occupancy surveys, and a random tessellation

  5. Long-Term Landscape Evolution of the Northparkes Region of the Lachlan Fold Belt, Australia: Constraints from Fission Track and Paleomagnetic Data.

    PubMed

    O'Sullivan; Gibson; Kohn; Pillans; Pain

    2000-01-01

    Apatite fission track thermochronology (AFTT) and paleomagnetic (PM) results have been used to constrain the Late Paleozoic to Cenozoic landscape evolution of the Lachlan Fold Belt (LFB) around the Northparkes copper-gold deposit in east-central New South Wales. The present-day landscape of this region of the LFB is relatively flat with little expression of the underlying rock and has previously been interpreted to indicate long-term stability of the region since the end of LFB orogenesis in the Early Carboniferous. This was presumably borne out by PM analyses from thick weathered horizons within open pits at the mine, which suggested that significant periods of weathering, and hence relative landscape stability, prevailed during the Early to middle Carboniferous and at some time during the Cenozoic. Results from AFTT analyses, however, indicate that the region must have experienced significant episodes of cooling/denudation during the mid-Permian to mid-Triassic and during the early Cenozoic, as well as episodes of heating/burial during the Late Carboniferous to mid-Permian and during the late Mesozoic. When combined, the AFTT and PM results are in fact consistent and indicate that since the late Paleozoic the landscape of the LFB around the Northparkes deposit has evolved through multiple episodes of denudation and deposition as well as periods of relative stability during which the thick weathering horizons formed. Together these results establish a complementary chronological framework that constrains the Late Palaeozoic to Cenozoic landscape evolution of the Northparkes region and highlights the importance of using dual data sets in elucidating the long-term landscape evolution of similar "stable" terranes.

  6. Superparamagnetic iron oxide nanoparticles function as a long-term, multi-modal imaging label for non-invasive tracking of implanted progenitor cells.

    PubMed

    Pacak, Christina A; Hammer, Peter E; MacKay, Allison A; Dowd, Rory P; Wang, Kai-Roy; Masuzawa, Akihiro; Sill, Bjoern; McCully, James D; Cowan, Douglas B

    2014-01-01

    The purpose of this study was to determine the ability of superparamagnetic iron oxide (SPIO) nanoparticles to function as a long-term tracking label for multi-modal imaging of implanted engineered tissues containing muscle-derived progenitor cells using magnetic resonance imaging (MRI) and X-ray micro-computed tomography (μCT). SPIO-labeled primary myoblasts were embedded in fibrin sealant and imaged to obtain intensity data by MRI or radio-opacity information by μCT. Each imaging modality displayed a detection gradient that matched increasing SPIO concentrations. Labeled cells were then incorporated in fibrin sealant, injected into the atrioventricular groove of rat hearts, and imaged in vivo and ex vivo for up to 1 year. Transplanted cells were identified in intact animals and isolated hearts using both imaging modalities. MRI was better able to detect minuscule amounts of SPIO nanoparticles, while μCT more precisely identified the location of heavily-labeled cells. Histological analyses confirmed that iron oxide particles were confined to viable, skeletal muscle-derived cells in the implant at the expected location based on MRI and μCT. These analyses showed no evidence of phagocytosis of labeled cells by macrophages or release of nanoparticles from transplanted cells. In conclusion, we established that SPIO nanoparticles function as a sensitive and specific long-term label for MRI and μCT, respectively. Our findings will enable investigators interested in regenerative therapies to non-invasively and serially acquire complementary, high-resolution images of transplanted cells for one year using a single label.

  7. Geodynamical Processes between Antarctica and India as revealed by very long baselines between the continents estimated from continuous and long-term GPS measurements

    NASA Astrophysics Data System (ADS)

    N, R.; Ec, M.; Akilan, A.

    2006-12-01

    To holistically understand the geodynamical and crustal deformation processes in the south of Indian peninsula between India and Antarctica, two global networks have been chosen that geodetically connect the two continents, the IGS Station at Diego Garcia (DGAR) being the common station between the two networks. 8 years of data from 1997 to 2005 were used. Very long baselines have been estimated from HYDE to other chosen IGS stations in and around India including DGAR. Similarly in the other network, very long baselines have been estimated from Kerguelen to other stations in and around Antarctica again including DGAR. Since the baseline length between HYDE, India and MAITRI, Antarctica is more than 10,000 km, it is mandatory to form these two different networks to improve the accuracy of the baseline measurements by GPS. This is to circumvent the limitation in the estimation of maximum base line length by GPS is of 6,900 km only due to the availability of less number of double difference observables in the GPS data analysis. Our analysis and results show increase of baseline lengths between Kerguelen in Antarctic plate and other stations and shortening of baseline lengths between HYDE in Indian plate and other common stations. By this global network analyses, the stations HYDE and MAITRI are geodetically tied through DGAR. With this geodetic tie up, having got the first geodetic signatures of the geodynamical processes between India and Antarctica, continuous monitoring and estimation would help enhancing the understanding the crustal deformation processes between these two continents despite many plates, micro plates and ridges in this study region.These estimations reveal clearly that the stations in the Australian plate are moving away from the Indian plate conforming to the recent Plate tectonic theory that India and Australia lie in two different plates with a diffuse boundary separating them. GPS derived velocity vectors for the Australian Plate also

  8. A Low Cost GPS System for Real-Time Tracking of Sounding Rockets

    NASA Technical Reports Server (NTRS)

    Markgraf, M.; Montenbruck, O.; Hassenpflug, F.; Turner, P.; Bull, B.; Bauer, Frank (Technical Monitor)

    2001-01-01

    In an effort to minimize the need for costly, complex, tracking radars, the German Space Operations Center has set up a research project for GPS based tracking of sounding rockets. As part of this project, a GPS receiver based on commercial technology for terrestrial applications has been modified to allow its use under the highly dynamical conditions of a sounding rocket flight. In addition, new antenna concepts are studied as an alternative to proven but costly wrap-around antennas.

  9. Living alongside railway tracks: Long-term effects of nocturnal noise on sleep and cardiovascular reactivity as a function of age.

    PubMed

    Tassi, Patricia; Rohmer, Odile; Schimchowitsch, Sarah; Eschenlauer, Arnaud; Bonnefond, Anne; Margiocchi, Florence; Poisson, Franck; Muzet, Alain

    2010-10-01

    Very few studies were devoted to permanent effects of nocturnal railway noise on sleep and cardiovascular reactivity. We investigated the effects of nocturnal railway noise on sleep and cardiovascular response in young and middle-aged adults living for many years either near a railway track or in a quiet area. Forty subjects (50% males) divided into two age groups (juniors: 26.2+/-3.6 and seniors: 56.2+/-4.2) participated in this experiment. Half of them lived near a railway track (RW group: 2.6 to 19 years) and the other half in a quiet environment (QE group: 8.1 to 14.2 years). After an adaptation night, all subjects underwent two nights in the laboratory: one control night and one noisy night (30 by-passes of a freight train). Sleep and cardiovascular modifications were assessed in response to noise. Sleep fragmentation indices were lower in RW subjects compared to QE whatever their age. In response to noise, there was a higher cardiovascular response rate to noise in RW juniors and a lower cardiovascular response rate in RW seniors compared to their age-paired QE counterparts. In conclusion, permanent exposure to nocturnal railway noise leads to decreased sleep fragmentation and to cardiovascular habituation. It is suggested that during the initial period experienced by residents living near railway tracks, nocturnal railway noise could induce a sensitization process on the autonomic response to noise reflecting a startle/defense reflex due to its functional significance, which progressively turns to habituation in the long-term if no adverse effect is experienced.

  10. Long-term outcomes of stereotactic body radiation therapy (SBRT) with fiducial tracking for inoperable stage I non-small cell lung cancer (NSCLC).

    PubMed

    Lischalk, Jonathan W; Woo, Stephanie M; Kataria, Shaan; Aghdam, Nima; Paydar, Ima; Repka, Michael C; Anderson, Eric D; Collins, Brian T

    2016-01-01

    Stereotactic body radiation therapy (SBRT) for stage I non-small cell lung cancer (NSCLC) is considered standard of care in the medically inoperable patient population. Multiple methods of SBRT delivery exist including fiducial-based tumor tracking, which allows for smaller treatment margins and avoidance of patient immobilization devices. We explore the long-term clinical outcomes of this novel fiducial-based SBRT method. In this single institutional retrospective review, we detail the outcomes of medically inoperable pathologically confirmed stage I NSCLC. Patients were treated with the Cyberknife SBRT system using a planning target volume (PTV) defined as a 5-mm expansion from gross tumor volume (GTV) without creation of an internal target volume (ITV). Dose was delivered in three or five equal fractions of 10 to 20 Gy. Pretreatment and posttreatment pulmonary function test (PFT) changes and evidence of late radiological rib fractures were analyzed for the majority of patients. Actuarial local control, locoregional control, distant control, and overall survival were calculated using the Kaplan-Meier method. Sixty-one patients with a median age of 75 years were available for analysis. The majority (80 %) of patients were deemed to be medically inoperable due to underlying pulmonary dysfunction. Eleven patients (18 %) developed symptomatic pneumothoraces secondary to fiducial placement under CT guidance, which precipitously dropped to 0 % following transition to bronchoscopic fiducial placement. The 2-year rib fracture risk was 21.4 % with a median time to rib fracture of 2.9 years. PFTs averaged over all patients and parameters demonstrated small absolute declines, 5.7 % averaged PFT decline, at approximately 1 year of follow-up, but only the diffusing capacity of lung for carbon monoxide (DLCO) demonstrated a statistically significant decline (10.29 vs. 9.01 mL/min/mmHg, p = 0.01). Five-year local control, locoregional control, and overall survival

  11. Monitoring distances travelled by horses using GPS tracking collars.

    PubMed

    Hampson, B A; Morton, J M; Mills, P C; Trotter, M G; Lamb, D W; Pollitt, C C

    2010-05-01

    The aims of this work were to (1) develop a low-cost equine movement tracking collar based on readily available components, (2) conduct preliminary studies assessing the effects of both paddock size and internal fence design on the movements of domestic horses, with and without foals at foot, and (3) describe distances moved by mares and their foals. Additional monitoring of free-ranging feral horses was conducted to allow preliminary comparisons with the movement of confined domestic horses. A lightweight global positioning system (GPS) data logger modified from a personal/vehicle tracker and mounted on a collar was used to monitor the movement of domestic horses in a range of paddock sizes and internal fence designs for 6.5-day periods. In the paddocks used (0.8-16 ha), groups of domestic horses exhibited a logarithmic response in mean daily distance travelled as a function of increasing paddock size, tending asymptotically towards approximately 7.5 km/day. The distance moved by newborn foals was similar to their dams, with total distance travelled also dependent on paddock size. Without altering available paddock area, paddock design, with the exception of a spiral design, did not significantly affect mean daily distance travelled. Feral horses (17.9 km/day) travelled substantially greater mean daily distances than domestic horses (7.2 km/day in 16-ha paddock), even when allowing for larger paddock size. Horses kept in stables or small yards and paddocks are quite sedentary in comparison with their feral relatives. For a given paddock area, most designs did not significantly affect mean daily distance travelled.

  12. Navigating the Return Trip from the Moon Using Earth-Based Ground Tracking and GPS

    NASA Technical Reports Server (NTRS)

    Berry, Kevin; Carpenter, Russell; Moreau, Michael C.; Lee, Taesul; Holt, Gregg N.

    2009-01-01

    NASA s Constellation Program is planning a human return to the Moon late in the next decade. From a navigation perspective, one of the most critical phases of a lunar mission is the series of burns performed to leave lunar orbit, insert onto a trans-Earth trajectory, and target a precise re-entry corridor in the Earth s atmosphere. A study was conducted to examine sensitivity of the navigation performance during this phase of the mission to the type and availability of tracking data from Earth-based ground stations, and the sensitivity to key error sources. This study also investigated whether GPS measurements could be used to augment Earth-based tracking data, and how far from the Earth GPS measurements would be useful. The ability to track and utilize weak GPS signals transmitted across the limb of the Earth is highly dependent on the configuration and sensitivity of the GPS receiver being used. For this study three GPS configurations were considered: a "standard" GPS receiver with zero dB antenna gain, a "weak signal" GPS receiver with zero dB antenna gain, and a "weak signal" GPS receiver with an Earth-pointing direction antenna (providing 10 dB additional gain). The analysis indicates that with proper selection and configuration of the GPS receiver on the Orion spacecraft, GPS can potentially improve navigation performance during the critical final phases of flight prior to Earth atmospheric entry interface, and may reduce reliance on two-way range tracking from Earth-based ground stations.

  13. Apatite fission track dating and long-term landscape evolution of the South Atlantic passive continental margin in the region of the Sierras Septentrionales in eastern Argentina

    NASA Astrophysics Data System (ADS)

    Pfister, S.; Glasmacher, P. A.; Kollenz, S.

    2013-12-01

    To understand the evolution of the passive continental margin in Argentina apatite fission track dating is an appropriate method, which will lead to new conclusions in this area. The Tandilia System, also called Sierras Septentrionales, is located south of the Río de la Plato Craton in eastern Argentina in the state of Buenos Aires. North of the hills Salado basin is orientated whereas the Claromeó basin is located south of the mountain range. In contrary to most basins along the southamerican passive continental margin the Tandilia-System and the neighbouring basins trend perpendicular to the coast line. The topography ranges between 50 and 250m within the study area and is therefore fairly flat. The igneous-metamorphic basement is pre-proterozoic in age build up of mainly granitic-tonalitic gneisses, migmatites, amphibolites, some ultramafic rocks and granitoid plutons and is overlain by a series of Neoproterozoic to early Paleozoic sediments (Cingolani, 2010). The aim of the study is to evaluate the long-term landscape evolution of the passive continental margin in eastern Argentina in terms of thermal history and exhumation. For that purpose samples were taken from the Sierra Septentrionales basement analyzed for the apatite-FT method. The results so far indicate apatite fission track ages between 146.2 (10.1) Ma and 200.4 (12.7) Ma, which shows all samples have been reseted. Still ongoing length measurements will lead to 2D thermo kinematic Hefty (Ketcham, 2005; Ketcham et al., 2009; Ketcham, 2007) models. This will leads to further more insights on the cooling history and tectonic activities in the research area. References: Cingolani C. A. (2010): The Tandilia System of Argentina as a southern extension of the Río de la Plata craton: an overview. Int. J. Earth Sci. (Geol. Rundsch.) (2011) 100:221-242, doi 10.1007/s00531-010-0611-5. Ketcham, R. A. (2005): Forward and inverse modeling of low-temperature thermochronometry data, in Low

  14. Spatiotemporal slip distributions of three long-term slow slip events beneath the Bungo Channel, southwest Japan, inferred from inversion analyses of GPS data

    NASA Astrophysics Data System (ADS)

    Yoshioka, Shoichi; Matsuoka, Yoshiko; Ide, Satoshi

    2015-06-01

    We estimated spatiotemporal slip distributions from three long-term slow slip events (L-SSEs) that occurred beneath the Bungo Channel at the convergent plate boundary between the subducting oceanic Philippine Sea plate and the continental Amurian plate in southwest Japan between 1997 and 1998, 2002 and 2004 and 2009 and 2011. For this purpose, we employed an inversion method using a Bayesian Information Criterion (ABIC), which included the following three prior constraints: the spatial slip distribution was smooth to some extent, slip directions were mostly oriented in the direction of plate convergence and the temporal change in slip was smooth to some extent. Our results revealed that the three L-SSEs had a common feature: slipped regions expanded southwestward at accelerating slip velocities. We also found that major slipped regions migrated southwestward by approximately 50-100 km yr-1. In contrast, southwestward and northeastward migration of the slipped regions, whose direction differed from event to event, was also identified before or after the periods when the slip velocities were at their greatest. Comparing the obtained spatiotemporal slip distributions of the three L-SSEs with slip-deficit rate distributions obtained in our previous study, we investigated the accumulation process of the slip deficit caused by slip-deficit rate distributions and the release processes of the slip deficit caused by the obtained spatiotemporal slip distributions of the three L-SSEs. At the western plate interface of the Bungo Channel, as the slip-deficit rate was small and the amounts of slips associated with the three L-SSEs were large, most of the accumulated slip deficit was estimated to have been released. In contrast, at the eastern plate interface, as the slip-deficit rate was large and the amounts of slips associated with the three L-SSEs were small, the slip deficit was estimated to have accumulated effectively. These results suggest that the slipped regions of the

  15. Long-term in vivo single-cell tracking reveals the switch of migration patterns in adult-born juxtaglomerular cells of the mouse olfactory bulb

    PubMed Central

    Liang, Yajie; Li, Kaizhen; Riecken, Kristoffer; Maslyukov, Anatoliy; Gomez-Nicola, Diego; Kovalchuk, Yury; Fehse, Boris; Garaschuk, Olga

    2016-01-01

    The behavior of adult-born cells can be easily monitored in cell culture or in lower model organisms, but longitudinal observation of individual mammalian adult-born cells in their native microenvironment still proves to be a challenge. Here we have established an approach named optical cell positioning system for long-term in vivo single-cell tracking, which integrates red-green-blue cell labeling with repeated angiography. By combining this approach with in vivo two-photon imaging technique, we characterized the in vivo migration patterns of adult-born neurons in the olfactory bulb. In contrast to the traditional view of mere radial migration of adult-born cells within the bulb, we found that juxtaglomerular cells switch from radial migration to long distance lateral migration upon arrival in their destination layer. This unique long-distance lateral migration has characteristic temporal (stop-and-go) and spatial (migratory, unidirectional or multidirectional) patterns, with a clear cell age-dependent decrease in the migration speed. The active migration of adult-born cells coincides with the time period of initial fate determination and is likely to impact on the integration sites of adult-born cells, their odor responsiveness, as well as their survival rate. PMID:27174051

  16. Constraints on the mechanism of long-term, steady subsidence at Medicine Lake volcano, northern California, from GPS, leveling, and InSAR

    USGS Publications Warehouse

    Poland, Michael P.; Burgmann, Roland; Dzurisin, Daniel; Lisowski, Michael; Masterlark, Timothy; Owen, Susan; Fink, Jonathan

    2006-01-01

    Leveling surveys across Medicine Lake volcano (MLV) have documented subsidence that is centered on the summit caldera and decays symmetrically on the flanks of the edifice. Possible mechanisms for this deformation include fluid withdrawal from a subsurface reservoir, cooling/crystallization of subsurface magma, loading by the volcano and dense intrusions, and crustal thinning due to tectonic extension (Dzurisin et al., 1991 [Dzurisin, D., Donnelly-Nolan, J.M., Evans, J.R., Walter, S.R., 1991. Crustal subsidence, seismicity, and structure near Medicine Lake Volcano, California. Journal of Geophysical Research 96, 16, 319-16, 333.]; Dzurisin et al., 2002 [Dzurisin, D., Poland, M.P., Bürgmann, R., 2002. Steady subsidence of Medicine Lake Volcano, Northern California, revealed by repeated leveling surveys. Journal of Geophysical Research 107, 2372, doi:10.1029/2001JB000893.]). InSAR data that approximate vertical displacements are similar to the leveling results; however, vertical deformation data alone are not sufficient to distinguish between source mechanisms. Horizontal displacements from GPS were collected in the Mt. Shasta/MLV region in 1996, 1999, 2000, 2003, and 2004. These results suggest that the region is part of the western Oregon block that is rotating about an Euler pole in eastern Oregon. With this rotation removed, most sites in the network have negligible velocities except for those near MLV caldera. There, measured horizontal velocities are less than predicted from ∼10 km deep point and dislocation sources of volume loss based on the leveling data; therefore volumetric losses simulated by these sources are probably not causing the observed subsidence at MLV. This result demonstrates that elastic models of subsurface volume change can provide misleading results where additional geophysical and geological constraints are unavailable, or if only vertical deformation is known. The deformation source must be capable of causing broad vertical deformation

  17. Constraints on the mechanism of long-term, steady subsidence at Medicine Lake volcano, northern California, from GPS, leveling, and InSAR

    NASA Astrophysics Data System (ADS)

    Poland, Michael; Bürgmann, Roland; Dzurisin, Daniel; Lisowski, Michael; Masterlark, Timothy; Owen, Susan; Fink, Jonathan

    2006-02-01

    Leveling surveys across Medicine Lake volcano (MLV) have documented subsidence that is centered on the summit caldera and decays symmetrically on the flanks of the edifice. Possible mechanisms for this deformation include fluid withdrawal from a subsurface reservoir, cooling/crystallization of subsurface magma, loading by the volcano and dense intrusions, and crustal thinning due to tectonic extension (Dzurisin et al., 1991 [Dzurisin, D., Donnelly-Nolan, J.M., Evans, J.R., Walter, S.R., 1991. Crustal subsidence, seismicity, and structure near Medicine Lake Volcano, California. Journal of Geophysical Research 96, 16, 319-16, 333.]; Dzurisin et al., 2002 [Dzurisin, D., Poland, M.P., Bürgmann, R., 2002. Steady subsidence of Medicine Lake Volcano, Northern California, revealed by repeated leveling surveys. Journal of Geophysical Research 107, 2372, doi:10.1029/2001JB000893.]). InSAR data that approximate vertical displacements are similar to the leveling results; however, vertical deformation data alone are not sufficient to distinguish between source mechanisms. Horizontal displacements from GPS were collected in the Mt. Shasta/MLV region in 1996, 1999, 2000, 2003, and 2004. These results suggest that the region is part of the western Oregon block that is rotating about an Euler pole in eastern Oregon. With this rotation removed, most sites in the network have negligible velocities except for those near MLV caldera. There, measured horizontal velocities are less than predicted from ˜10 km deep point and dislocation sources of volume loss based on the leveling data; therefore volumetric losses simulated by these sources are probably not causing the observed subsidence at MLV. This result demonstrates that elastic models of subsurface volume change can provide misleading results where additional geophysical and geological constraints are unavailable, or if only vertical deformation is known. The deformation source must be capable of causing broad vertical deformation

  18. A demonstration of unified TDRS/GPS tracking and orbit determination

    NASA Astrophysics Data System (ADS)

    Haines, B.; Lichten, S.; Srinivasan, J.; Young, L.

    1995-05-01

    We describe results from an experiment in which TDRS and GPS satellites were tracked simultaneously from a small (3 station) ground network in the western United States. We refer to this technique as 'GPS-like tracking' (GLT) since the user satellite - in this case TDRS - is essentially treated as a participant in the GPS constellation. In the experiment, the TDRS K(sub space-to-ground link (SGL) was tracked together with GPS L-band signals in enhanced geodetic-quality GPS receivers (TurboRogue). The enhanced receivers simultaneously measured and recorded both the TDRS SGL and the GPS carrier phases with sub-mm precision, enabling subsequent precise TDRS orbit determination with differential GPS techniques. A small number of calibrated ranging points from routine operations at the TDRS ground station (White Sands, NM) were used to supplement the GLT measurements in order to improve determination of the TDRS longitude. Various tests performed on TDRS ephemerides derived from data collected during this demonstration - including comparisons with the operational precise orbit generated by NASA Goddard Space Flight Center - provide evidence that the TDRS orbits have been determined to better than 25 m with the GLT technique.

  19. A demonstration of unified TDRS/GPS tracking and orbit determination

    NASA Technical Reports Server (NTRS)

    Haines, B.; Lichten, S.; Srinivasan, J.; Young, L.

    1995-01-01

    We describe results from an experiment in which TDRS and GPS satellites were tracked simultaneously from a small (3 station) ground network in the western United States. We refer to this technique as 'GPS-like tracking' (GLT) since the user satellite - in this case TDRS - is essentially treated as a participant in the GPS constellation. In the experiment, the TDRS K(sub space-to-ground link (SGL) was tracked together with GPS L-band signals in enhanced geodetic-quality GPS receivers (TurboRogue). The enhanced receivers simultaneously measured and recorded both the TDRS SGL and the GPS carrier phases with sub-mm precision, enabling subsequent precise TDRS orbit determination with differential GPS techniques. A small number of calibrated ranging points from routine operations at the TDRS ground station (White Sands, NM) were used to supplement the GLT measurements in order to improve determination of the TDRS longitude. Various tests performed on TDRS ephemerides derived from data collected during this demonstration - including comparisons with the operational precise orbit generated by NASA Goddard Space Flight Center - provide evidence that the TDRS orbits have been determined to better than 25 m with the GLT technique.

  20. Long-term landscape evolution of the South Atlantic "passive" continental margin in Eastern Argentina using apatite fission-track thermochronology

    NASA Astrophysics Data System (ADS)

    Pfister, Sabrina; Kollenz, Sebastian; Glasmacher, Ulrich A.

    2015-04-01

    To understand the evolution of the "passive" continental margin in Argentina low temperature thermochronology is an appropriate method, which might lead to new insights in this area. The Tandilia System, also called Sierras Septentrionales, is located south of the Río de la Plato Craton in eastern Argentina in the state of Buenos Aires. North of the hills the Salado basin is located whereas the Claromecó basin is situated south of the mountain range. In contrary to most basins along the South American "passive" continental margin, the Tandilia-System and the neighbouring basins trend perpendicular to the coast line. The topography is fairly flat with altitudes up to 350 m. The igneous-metamorphic basement is pre-Proterozoic in age and build up of mainly granitic-tonalitic gneisses, migmatites, amphibolites, some ultramafic rocks and granitoid plutons. It is overlain by a series of Neoproterozoic to early Paleozoic sedimentary rocks (Cingolani 2011), like siliciclastic rocks, dolostones, shales and limestones (Demoulin 2005). The aim of the study is to quantify the long-term landscape evolution of the "passive" continental margin in eastern Argentina in terms of thermal, exhumation and tectonic evolution. For that purpose, samples were taken from the basement of the Sierra Septentrionales and analyzed with the apatite fission-track method. Further 2-D thermokinematic modeling was conducted with the computer code HeFTy (Ketcham 2005; Ketcham 2007; Ketcham et al. 2009). Because there are different hypotheses in literature regarding the geological evolution of this area two different models were generated, one after Demoulin et al. (2005) and another after Zalba et al.(2007). All samples were taken from the Neoproterozoic igneous-metamorphic basement. Apatite fission-track ages range from 101.6 (9.4) to 228.9 (22.3) Ma, and, therefore, are younger than their formation age, indicating all samples have been thermally reset. Six samples accomplished enough confined

  1. Left ventricular function after takotsubo is not fully recovered in long-term follow-up: A speckle tracking echocardiography study.

    PubMed

    Nowak, Radoslaw; Fijalkowska, Marta; Gilis-Malinowska, Natasza; Jaguszewski, Milosz; Galaska, Rafal; Rojek, Agnieszka; Narkiewicz, Krzysztof; Gruchala, Marcin; Fijalkowski, Marcin

    2017-01-01

    Complete improvement of left ventricle (LV) systolic function is an essential feature of takotsubo cardiomyopathy (TTC). It is suggested that 2-dimensional speckle tracking echocardiography (2D STE) can evaluate LV dysfunction more accurately than conventional echocardiography. Thus, the purpose of this research was to assertain whether LV function recovery is complete after the acute phase of TTC using 2D STE commencing 6 to 9 months after discharge. Thirty patients (29 females, 67 ± 11 years) with an apical ballooning TTC pattern 225.5 ± 27.4 days after their index event were enrolled. The control group consisted of 20 (19 females, 64 ± 9 years) age- and sex-matched volunteers without structural heart disease. Classic echocardiographic parameters, longitudinal strain and LV twist parameters were assessed and compared between the groups. There were no differences in traditional LV systolic, diastolic parameters and in global peak longitudinal strain. In comparison to controls, patients with TTC had lower mean apical rotation (14.4° ± 6.5° vs. 18.3° ± 6.7°; p = 0.048), slower mean peak early diastolic apical rotation rate (-85.1-°/s ± 40.9-°/s vs -119.4-°/s ± 41.9-°/s; p = 0.006) and higher pre-stretch index in the apex (2.16, IQR 0.33-5.50 vs. 0.00, IQR 0.00-2.95, p = 0.008). The improvement of LV function in patients with TTC as assessed by 2D STE may not always be complete. Some residual abnormalities in LV apex function were observed in long-term recovery following TTC episodes.

  2. New approaches for tracking earth orbiters using modified GPS ground receivers

    NASA Technical Reports Server (NTRS)

    Lichten, S. M.; Young, L. E.; Nandi, S.; Haines, B. J.; Dunn, C. E.; Edwards, C. D.

    1993-01-01

    A Global Positioning System (GPS) flight receiver provides a means to precisely determine orbits for satellites in low to moderate altitude orbits. Above a 5000-km altitude, however, relatively few GPS satellites are visible. New approaches to orbit determination for satellites at higher altitudes could reduce DSN antenna time needed to provide navigation and orbit determination support to future missions. Modification of GPS ground receivers enables a beacon from the orbiter to be tracked simultaneously with GPS data. The orbit accuracy expected from this GPS-like tracking (GLT) technique is expected to be in the range of a few meters or better for altitudes up to 100,000 km with a global ground network. For geosynchronous satellites, however, there are unique challenges due to geometrical limitations and to the lack of strong dynamical signature in tracking data. We examine two approaches for tracking the Tracking and Data Relay Satellite System (TDRSS) geostationary orbiters. One uses GLT with a global network; the other relies on a small 'connected element' ground network with a distributed clock for short-baseline differential carrier phase (SB Delta Phi). We describe an experiment planned for late 1993, which will combine aspects of both GLT and SB Delta Phi, to demonstrate a new approach for tracking the Tracking and Data Relay Satellites (TDRSs) that offers a number of operationally convenient and attractive features. The TDRS demonstration will be in effect a proof-of-concept experiment for a new approach to tracking spacecraft which could be applied more generally to deep-space as well as near-Earth regimes.

  3. Long Term Prognosis

    MedlinePlus

    ... TERM PROGNOSIS The long-term outlook of pediatric cardiomyopathy continues to be unpredictable because it occurs with ... a child also depends on the type of cardiomyopathy and the stage the disease is first diagnosed. ...

  4. Comparison of Right Ventricle Systolic Function between Long-Term Anabolic-Androgenic Steroid User and Nonuser Bodybuilder Athletes: A Study of Two-Dimensional Speckle Tracking Echocardiography.

    PubMed

    Alizade, Elnur; Avci, Anil; Tabakcı, Mehmet Mustafa; Toprak, Cuneyt; Zehir, Regayip; Acar, Goksel; Kargin, Ramazan; Emiroğlu, Mehmet Yunas; Akçakoyun, Mustafa; Pala, Selçuk

    2016-08-01

    Right ventricular (RV) effects of long-term use of anabolic-androgenic steroids (AAS) are not clearly known. The aim of this study was to assess RV systolic functions by two-dimensional speckle tracking echocardiography (2DSTE) in AAS user and nonuser bodybuilders. A total of 33 competitive male bodybuilders (15 AAS users, 18 AAS nonusers) were assessed. To assess RV systolic functions, all participants underwent standard two-dimensional and Doppler echocardiography, and 2DSTE. Interventricular septal thickness, left ventricle posterior wall thickness, relative wall thickness, and left ventricle mass index were significantly higher in AAS users than nonusers. While standard diastolic parameters were not statistically different between the groups, tissue Doppler parameters including RV E' and E'/A' were lower in AAS users than nonusers (10.1 ± 2.0 vs. 12.7 ± 2.1; P = 0.001, 1.1 ± 0.1 vs. 1.5 ± 0.4; P = 0.009, respectively). Tricuspid annular plane systolic excursion, RV fractional area change, and RV S' were in normal ranges. However, RV S' was found to be lower in users than nonusers (12.2 ± 2.2 vs. 14.6 ± 2.8, P = 0.011). RV free wall longitudinal strain and strain rate were decreased in AAS users in comparison with nonusers (-20.2 ± 3.1 vs. -23.3 ± 3.5; P = 0.012, -3.2 ± 0.1 vs. -3.4 ± 0.1; P = 0.022, respectively). In addition, there were good correlations between 2DSTE parameters and RV S', E', and E'/A'. Despite normal standard systolic echo parameters, peak systolic RV free wall strain and strain rate were reduced in AAS user bodybuilders in comparison with nonusers. Strain and strain rate by 2DSTE may be useful for early determination of subclinical RV dysfunction in AAS user bodybuilders. © 2016, Wiley Periodicals, Inc.

  5. Feathered Detectives: Real-Time GPS Tracking of Scavenging Gulls Pinpoints Illegal Waste Dumping.

    PubMed

    Navarro, Joan; Grémillet, David; Afán, Isabel; Ramírez, Francisco; Bouten, Willem; Forero, Manuela G

    2016-01-01

    Urban waste impacts human and environmental health, and waste management has become one of the major challenges of humanity. Concurrently with new directives due to manage this human by-product, illegal dumping has become one of the most lucrative activities of organized crime. Beyond economic fraud, illegal waste disposal strongly enhances uncontrolled dissemination of human pathogens, pollutants and invasive species. Here, we demonstrate the potential of novel real-time GPS tracking of scavenging species to detect environmental crime. Specifically, we were able to detect illegal activities at an officially closed dump, which was visited recurrently by 5 of 19 GPS-tracked yellow-legged gulls (Larus michahellis). In comparison with conventional land-based surveys, GPS tracking allows a much wider and cost-efficient spatiotemporal coverage, even of the most hazardous sites, while GPS data accessibility through the internet enables rapid intervention. Our results suggest that multi-species guilds of feathered detectives equipped with GPS and cameras could help fight illegal dumping at continental scales. We encourage further experimental studies, to infer waste detection thresholds in gulls and other scavenging species exploiting human waste dumps.

  6. Feathered Detectives: Real-Time GPS Tracking of Scavenging Gulls Pinpoints Illegal Waste Dumping

    PubMed Central

    Grémillet, David; Afán, Isabel; Ramírez, Francisco; Bouten, Willem; Forero, Manuela G.

    2016-01-01

    Urban waste impacts human and environmental health, and waste management has become one of the major challenges of humanity. Concurrently with new directives due to manage this human by-product, illegal dumping has become one of the most lucrative activities of organized crime. Beyond economic fraud, illegal waste disposal strongly enhances uncontrolled dissemination of human pathogens, pollutants and invasive species. Here, we demonstrate the potential of novel real-time GPS tracking of scavenging species to detect environmental crime. Specifically, we were able to detect illegal activities at an officially closed dump, which was visited recurrently by 5 of 19 GPS-tracked yellow-legged gulls (Larus michahellis). In comparison with conventional land-based surveys, GPS tracking allows a much wider and cost-efficient spatiotemporal coverage, even of the most hazardous sites, while GPS data accessibility through the internet enables rapid intervention. Our results suggest that multi-species guilds of feathered detectives equipped with GPS and cameras could help fight illegal dumping at continental scales. We encourage further experimental studies, to infer waste detection thresholds in gulls and other scavenging species exploiting human waste dumps. PMID:27448048

  7. Long-term denudation rates in the central Himalayas: What can we learn from detrital zircon fission-track dating and specific-stream power modeling?

    NASA Astrophysics Data System (ADS)

    Bookhagen, B.; Burbank, D. W.; Brewer, I. D.; Garver, J. I.

    2005-12-01

    The central Himalaya encompasses areas characterized by high rates of rock uplift and erosion. It is also heavily influenced by the Indian summer monsoon, which modulates the sediment-transport capacity of Himalayan rivers. In order to constrain long-term denudation rates, we analyzed detrital zircon fission-track samples from 6 major river catchments that span 800 km along the southern flank of the central Himalaya. The age distribution of each sample (~70 zircons counted) reflects spatial variations in catchment denudation at million year time scales. Five catchments have similar grain-age distributions with a primary population of ages centered at 5±1 Ma. Several of these catchments display a secondary population of ages ranging from 12-15 Ma. However, the biggest catchment (Karnali) in a central position is characterized by a dominant population of older grain ages centered at ~10 Ma. Here, we seek to explain these puzzling results by using stream power modeling based on high-resolution space-borne precipitation (TRMM) and topography (SRTM). We use precipitation to predict discharges and thus derive a more realistic stream-power model, with higher values in the eastern catchments and lower values in the more arid, northern regions that are draining parts of the Tibetan Plateau. The precipitation distribution shows two distinctive orogen-parallel bands of high rainfall values: (1) at the orographic barriers of ~1 km elevation in frontal part of the Lesser Himalaya; and (2) around 2-3 km of elevation on the southern flank of the Greater Himalaya. This more northerly band is discontinuous along the range, and is nearly absent in the Karnali catchment, thus creating drier conditions and lower specific discharges. We hypothesize that regions of high specific stream power will coincide spatially with the dominant sources of eroded sediment. Given that cooling ages depend on both altitude and latitudinal position in a laterally advecting orogen, spatial differences

  8. Quantifying movement demands of AFL football using GPS tracking.

    PubMed

    Wisbey, Ben; Montgomery, Paul G; Pyne, David B; Rattray, Ben

    2010-09-01

    Global positioning system (GPS) monitoring of movement patterns is widespread in elite football including the Australian Football League (AFL). However documented analysis of this activity is lacking. We quantified the movement patterns of AFL football and differences between nomadic (midfield), forward and defender playing positions, and determined whether the physical demands have increased over a four season period. Selected premiership games were monitored during the 2005 (n=80 game files), 2006 (n=244), 2007 (n=632) and 2008 (n=793) AFL seasons. Players were fitted with a shoulder harness containing a GPS unit. GPS data were downloaded after games and the following measures extracted: total distance (km), time in various speed zones, maximum speed, number of surges, accelerations, longest continuous efforts and a derived exertion index representing playing intensity. In 2008 nomadic players covered per game 3.4% more total distance (km), had 4.8% less playing time (min), a 17% higher exertion index (per min), and 23% more time running >18kmh(-1) than forwards and defenders (all p<0.05). Physical demands were substantially higher in the 2008 season compared with 2005: an 8.4% increase in mean speed, a 14% increase in intensity (exertion index) and a 9.0% decrease in playing time (all p<0.05). Nomadic players in AFL work substantially harder than forwards and defenders in covering more ground and at higher running intensities. Increases in the physical demands of AFL football were evident between 2005 and 2008. The increasing speed of the game has implications for game authorities, players and coaching staff.

  9. PFISR GPS tracking mode for researching high-latitude ionospheric electron density gradients associated with GPS scintillation

    NASA Astrophysics Data System (ADS)

    Loucks, D. C.; Palo, S. E.; Pilinski, M.; Crowley, G.; Azeem, S. I.; Hampton, D. L.

    2016-12-01

    Ionospheric behavior in the high-latitudes can significantly impact Ultra High Frequency (UHF) signals in the 300 MHz to 3 GHz band, resulting in degradation of Global Positioning System (GPS) position solutions and satellite communications interruptions. To address these operational concerns, a need arises to identify and understand the ionospheric structure that leads to disturbed conditions in the Arctic. Structures in the high-latitude ionosphere are known to change on the order of seconds or less, can be decameters to kilometers in scale, and elongate across magnetic field lines at auroral latitudes. Nominal operations at Poker Flat Incoherent Scatter Radar (PFISR) give temporal resolution on the order of minutes, and range resolution on the order of tens of kilometers, while specialized GPS receivers available for ionospheric sensing have a 100Hz observation sampling rate. One of these, ASTRA's Connected Autonomous Space Environment Sensor (CASES) is used for this study. We have developed a new GPS scintillation tracking mode for PFISR to address open scientific questions regarding temporal and spatial electron density gradients. The mode will be described, a number of experimental campaigns will be analyzed, and results and lessons learned will be presented.

  10. Impact of tracking loop settings of the Swarm GPS receiver on gravity field recovery

    NASA Astrophysics Data System (ADS)

    Dahle, C.; Arnold, D.; Jäggi, A.

    2017-06-01

    The Swarm mission consists of three identical satellites equipped with GPS receivers and orbiting in near-polar low Earth orbits. Thus, they can be used to determine the Earth's gravity field by means of high-low satellite-to-satellite tracking (hl-SST). However, first results by several groups have revealed systematic errors both in precise science orbits and resulting gravity field solutions which are caused by ionospheric disturbances affecting the quality of Swarm GPS observations. Looking at gravity field solutions, the errors lead to systematic artefacts located in two bands north and south of the geomagnetic equator. In order to reduce these artefacts, erroneous GPS observations can be identified and rejected before orbit and gravity field processing, but this may also lead to slight degradations of orbit and low degree gravity field coefficient quality. Since the problems were believed to be receiver-specific, the GPS tracking loop bandwidths onboard Swarm have been widened several times starting in May 2015. The influence of these tracking loop updates on Swarm orbits and, particularly, gravity field solutions is investigated in this work. The main findings are that the first updates increasing the bandwidth from 0.25 Hz to 0.5 Hz help to significantly improve the quality of Swarm gravity fields and that the improvements are even larger than those achieved by GPS data rejection. It is also shown that these improvements are indeed due to an improved quality of GPS observations around the geomagnetic equator, and not due to missing observations in these regions. As the ionospheric activity is rather low in the most recent months, the effect of the tracking loop updates in summer 2016 cannot be properly assessed yet. Nevertheless, the quality of Swarm gravity field solutions has already improved after the first updates which is especially beneficial in view of filling the upcoming gap between the GRACE and GRACE Follow-on missions with hl-SST gravity products.

  11. Vector map geo-location using GPS tracks

    NASA Astrophysics Data System (ADS)

    Bao, Yuanlu; Xu, Hao; Liu, Zhenan

    2007-06-01

    Geographic Information Systems, especially accurate digital traffic maps, have been becoming widely used in the Intelligent Transportation Systems. The GPS data usually are more accurate than the pre-existing base map data. This paper introduces a new cartography procedure for making digital map from a start-up paper map, which has no geography data (longitude and latitude). Contrary to traditional map-making which is first a precise survey-cartography and follow-on digital controlled mapping, the new procedure is first extracting layer from a raster map and vectorization, follow-on geo-adjusting for pinpointing all nodes on the vector map. There are two key processes in the new digital map-making technique. First, the map layer extraction is controlled by output feedback for optimal recognition of road network. Second, a dynamic topological mapping is developed for geo-location and improving the accuracy of vector traffic map by utilizing some recorded GPS data as the controlled pinpoint samples. Different from those traditional geolocation methods such as affine mapping, and the rubber-streeting with manual point-by-point matching, the new adjusting is decomposed into a series of optimal topological sub-mapping on relative sub-map region. Based on pinpointing one sample point to its accuracy location, the sub-mapping adjusts all nodes within the sub-map region.

  12. Long Term Quadrotor Stabilization

    DTIC Science & Technology

    2011-03-01

    navigation satellite systems ( GNSS ), such as the Global Position- ing System (GPS), are either unavailable or unusable due to low signal strength or...Programmable Gate Array GNSS Global Navigation Satellite Systems GPS Global Positioning System IMU Inertial Measurement Unit LADAR Laser Detection and...desired that these vehicles be able to navigate in the absence of any type of global navigation satellite system ( GNSS ) because these environments make

  13. Performance Evaluation of Block Acquisition and Tracking Algorithms Using an Open Source GPS Receiver Platform

    NASA Technical Reports Server (NTRS)

    Ramachandran, Ganesh K.; Akopian, David; Heckler, Gregory W.; Winternitz, Luke B.

    2011-01-01

    Location technologies have many applications in wireless communications, military and space missions, etc. US Global Positioning System (GPS) and other existing and emerging Global Navigation Satellite Systems (GNSS) are expected to provide accurate location information to enable such applications. While GNSS systems perform very well in strong signal conditions, their operation in many urban, indoor, and space applications is not robust or even impossible due to weak signals and strong distortions. The search for less costly, faster and more sensitive receivers is still in progress. As the research community addresses more and more complicated phenomena there exists a demand on flexible multimode reference receivers, associated SDKs, and development platforms which may accelerate and facilitate the research. One of such concepts is the software GPS/GNSS receiver (GPS SDR) which permits a facilitated access to algorithmic libraries and a possibility to integrate more advanced algorithms without hardware and essential software updates. The GNU-SDR and GPS-SDR open source receiver platforms are such popular examples. This paper evaluates the performance of recently proposed block-corelator techniques for acquisition and tracking of GPS signals using open source GPS-SDR platform.

  14. Using GPS-enabled cell phones to track the travel patterns of adolescents

    PubMed Central

    Wiehe, Sarah E; Carroll, Aaron E; Liu, Gilbert C; Haberkorn, Kelly L; Hoch, Shawn C; Wilson, Jeffery S; Fortenberry, J Dennis

    2008-01-01

    Background Few tools exist to directly measure the microsocial and physical environments of adolescents in circumstances where participatory observation is not practical or ethical. Yet measuring these environments is important as they are significantly associated with adolescent health-risk. For example, health-related behaviors such as cigarette smoking often occur in specific places where smoking may be relatively surreptitious. Results We assessed the feasibility of using GPS-enabled cell phones to track adolescent travel patterns and gather daily diary data. We enrolled 15 adolescent women from a clinic-based setting and asked them to carry the phones for 1 week. We found that these phones can accurately and reliably track participant locations, as well as record diary information on adolescent behaviors. Participants had variable paths extending beyond their immediate neighborhoods, and denied that GPS-tracking influenced their activity. Conclusion GPS-enabled cell phones offer a feasible and, in many ways, ideal modality of monitoring the location and travel patterns of adolescents. In addition, cell phones allow space- and time-specific interaction, probing, and intervention which significantly extends both research and health promotion beyond a clinical setting. Future studies can employ GPS-enabled cell phones to better understand adolescent environments, how they are associated with health-risk behaviors, and perhaps intervene to change health behavior. PMID:18495025

  15. Using GPS-enabled cell phones to track the travel patterns of adolescents.

    PubMed

    Wiehe, Sarah E; Carroll, Aaron E; Liu, Gilbert C; Haberkorn, Kelly L; Hoch, Shawn C; Wilson, Jeffery S; Fortenberry, J Dennis

    2008-05-21

    Few tools exist to directly measure the microsocial and physical environments of adolescents in circumstances where participatory observation is not practical or ethical. Yet measuring these environments is important as they are significantly associated with adolescent health-risk. For example, health-related behaviors such as cigarette smoking often occur in specific places where smoking may be relatively surreptitious. We assessed the feasibility of using GPS-enabled cell phones to track adolescent travel patterns and gather daily diary data. We enrolled 15 adolescent women from a clinic-based setting and asked them to carry the phones for 1 week. We found that these phones can accurately and reliably track participant locations, as well as record diary information on adolescent behaviors. Participants had variable paths extending beyond their immediate neighborhoods, and denied that GPS-tracking influenced their activity. GPS-enabled cell phones offer a feasible and, in many ways, ideal modality of monitoring the location and travel patterns of adolescents. In addition, cell phones allow space- and time-specific interaction, probing, and intervention which significantly extends both research and health promotion beyond a clinical setting. Future studies can employ GPS-enabled cell phones to better understand adolescent environments, how they are associated with health-risk behaviors, and perhaps intervene to change health behavior.

  16. Error analysis of real time and post processed or bit determination of GFO using GPS tracking

    NASA Technical Reports Server (NTRS)

    Schreiner, William S.

    1991-01-01

    The goal of the Navy's GEOSAT Follow-On (GFO) mission is to map the topography of the world's oceans in both real time (operational) and post processed modes. Currently, the best candidate for supplying the required orbit accuracy is the Global Positioning System (GPS). The purpose of this fellowship was to determine the expected orbit accuracy for GFO in both the real time and post-processed modes when using GPS tracking. This report presents the work completed through the ending date of the fellowship.

  17. Travel patterns during pregnancy: comparison between Global Positioning System (GPS) tracking and questionnaire data

    PubMed Central

    2013-01-01

    Background Maternal exposures to traffic-related air pollution have been associated with adverse pregnancy outcomes. Exposures to traffic-related air pollutants are strongly influenced by time spent near traffic. However, little is known about women’s travel activities during pregnancy and whether questionnaire-based data can provide reliable information on travel patterns during pregnancy. Objectives Examine women’s in-vehicle travel behavior during pregnancy and examine the difference in travel data collected by questionnaire and global positioning system (GPS) and their potential for exposure error. Methods We measured work-related travel patterns in 56 pregnant women using a questionnaire and one-week GPS tracking three times during pregnancy (<20 weeks, 20–30 weeks, and >30 weeks of gestation). We compared self-reported activities with GPS-derived trip distance and duration, and examined potentially influential factors that may contribute to differences. We also described in-vehicle travel behavior by pregnancy periods and influences of demographic and personal factors on daily travel times. Finally, we estimated personal exposure to particle-bound polycyclic aromatic hydrocarbon (PB-PAH) and examined the magnitude of exposure misclassification using self-reported vs. GPS travel data. Results Subjects overestimated both trip duration and trip distance compared to the GPS data. We observed moderately high correlations between self-reported and GPS-recorded travel distance (home to work trips: r = 0.88; work to home trips: r = 0.80). Better agreement was observed between the GPS and the self-reported travel time for home to work trips (r = 0.77) than work to home trips (r = 0.64). The subjects on average spent 69 and 93 minutes traveling in vehicles daily based on the GPS and self-reported data, respectively. Longer daily travel time was observed among participants in early pregnancy, and during certain pregnancy periods in women with

  18. Travel patterns during pregnancy: comparison between Global Positioning System (GPS) tracking and questionnaire data.

    PubMed

    Wu, Jun; Jiang, Chengsheng; Jaimes, Guillermo; Bartell, Scott; Dang, Andy; Baker, Dean; Delfino, Ralph J

    2013-10-09

    Maternal exposures to traffic-related air pollution have been associated with adverse pregnancy outcomes. Exposures to traffic-related air pollutants are strongly influenced by time spent near traffic. However, little is known about women's travel activities during pregnancy and whether questionnaire-based data can provide reliable information on travel patterns during pregnancy. Examine women's in-vehicle travel behavior during pregnancy and examine the difference in travel data collected by questionnaire and global positioning system (GPS) and their potential for exposure error. We measured work-related travel patterns in 56 pregnant women using a questionnaire and one-week GPS tracking three times during pregnancy (<20 weeks, 20-30 weeks, and >30 weeks of gestation). We compared self-reported activities with GPS-derived trip distance and duration, and examined potentially influential factors that may contribute to differences. We also described in-vehicle travel behavior by pregnancy periods and influences of demographic and personal factors on daily travel times. Finally, we estimated personal exposure to particle-bound polycyclic aromatic hydrocarbon (PB-PAH) and examined the magnitude of exposure misclassification using self-reported vs. GPS travel data. Subjects overestimated both trip duration and trip distance compared to the GPS data. We observed moderately high correlations between self-reported and GPS-recorded travel distance (home to work trips: r = 0.88; work to home trips: r = 0.80). Better agreement was observed between the GPS and the self-reported travel time for home to work trips (r = 0.77) than work to home trips (r = 0.64). The subjects on average spent 69 and 93 minutes traveling in vehicles daily based on the GPS and self-reported data, respectively. Longer daily travel time was observed among participants in early pregnancy, and during certain pregnancy periods in women with higher education attainment, higher income

  19. Lightweight GPS-tags, one giant leap for wildlife tracking? An assessment approach.

    PubMed

    Recio, Mariano R; Mathieu, Renaud; Denys, Paul; Sirguey, Pascal; Seddon, Philip J

    2011-01-01

    Recent technological improvements have made possible the development of lightweight GPS-tagging devices suitable to track medium-to-small sized animals. However, current inferences concerning GPS performance are based on heavier designs, suitable only for large mammals. Lightweight GPS-units are deployed close to the ground, on species selecting micro-topographical features and with different behavioural patterns in comparison to larger mammal species. We assessed the effects of vegetation, topography, motion, and behaviour on the fix success rate for lightweight GPS-collar across a range of natural environments, and at the scale of perception of feral cats (Felis catus). Units deployed at 20 cm above the ground in sites of varied vegetation and topography showed that trees (native forest) and shrub cover had the largest influence on fix success rate (89% on average); whereas tree cover, sky availability, number of satellites and horizontal dilution of position (HDOP) were the main variables affecting location error (±39.5 m and ±27.6 m before and after filtering outlier fixes). Tests on HDOP or number of satellites-based screening methods to remove inaccurate locations achieved only a small reduction of error and discarded many accurate locations. Mobility tests were used to simulate cats' motion, revealing a slightly lower performance as compared to the fixed sites. GPS-collars deployed on 43 cats showed no difference in fix success rate by sex or season. Overall, fix success rate and location error values were within the range of previous tests carried out with collars designed for larger species. Lightweight GPS-tags are a suitable method to track medium to small size species, hence increasing the range of opportunities for spatial ecology research. However, the effects of vegetation, topography and behaviour on location error and fix success rate need to be evaluated prior to deployment, for the particular study species and their habitats.

  20. Lightweight GPS-Tags, One Giant Leap for Wildlife Tracking? An Assessment Approach

    PubMed Central

    Recio, Mariano R.; Mathieu, Renaud; Denys, Paul; Sirguey, Pascal; Seddon, Philip J.

    2011-01-01

    Recent technological improvements have made possible the development of lightweight GPS-tagging devices suitable to track medium-to-small sized animals. However, current inferences concerning GPS performance are based on heavier designs, suitable only for large mammals. Lightweight GPS-units are deployed close to the ground, on species selecting micro-topographical features and with different behavioural patterns in comparison to larger mammal species. We assessed the effects of vegetation, topography, motion, and behaviour on the fix success rate for lightweight GPS-collar across a range of natural environments, and at the scale of perception of feral cats (Felis catus). Units deployed at 20 cm above the ground in sites of varied vegetation and topography showed that trees (native forest) and shrub cover had the largest influence on fix success rate (89% on average); whereas tree cover, sky availability, number of satellites and horizontal dilution of position (HDOP) were the main variables affecting location error (±39.5 m and ±27.6 m before and after filtering outlier fixes). Tests on HDOP or number of satellites-based screening methods to remove inaccurate locations achieved only a small reduction of error and discarded many accurate locations. Mobility tests were used to simulate cats' motion, revealing a slightly lower performance as compared to the fixed sites. GPS-collars deployed on 43 cats showed no difference in fix success rate by sex or season. Overall, fix success rate and location error values were within the range of previous tests carried out with collars designed for larger species. Lightweight GPS-tags are a suitable method to track medium to small size species, hence increasing the range of opportunities for spatial ecology research. However, the effects of vegetation, topography and behaviour on location error and fix success rate need to be evaluated prior to deployment, for the particular study species and their habitats. PMID:22163286

  1. GPS

    NASA Technical Reports Server (NTRS)

    Webb, Frank H.

    2006-01-01

    Geodetic networks support the TRF requirements of NASA ESE missions. Each of SLR, VLBI, GPS substantially and uniquely contributes to TRF determination. NASA's SLR, VLBI, and GPS groups collaborate toward wide-ranging improvements in the next 5 years. NASA leverages considerable resources through its significant activity in international services. NASA faces certain challenges in continuing and advancing these activities. The Terrestrial Reference Frame (TRF) is an accurate, stable set of positions and velocities. The TRF provides the stable coordinate system that allows us to link measurements over space and time. The geodetic networks provide data for determination of the TRF as well as direct science observations.

  2. A Low Cost GPS System for Real-Time Tracking of Sounding Rockets

    NASA Technical Reports Server (NTRS)

    Markgraf, M.; Montenbruck, O.; Hassenpflug, F.; Turner, P.; Bull, B.; Bauer, Frank (Technical Monitor)

    2001-01-01

    This paper describes the development as well as the on-ground and the in-flight evaluation of a low cost Global Positioning System (GPS) system for real-time tracking of sounding rockets. The flight unit comprises a modified ORION GPS receiver and a newly designed switchable antenna system composed of a helical antenna in the rocket tip and a dual-blade antenna combination attached to the body of the service module. Aside from the flight hardware a PC based terminal program has been developed to monitor the GPS data and graphically displays the rocket's path during the flight. In addition an Instantaneous Impact Point (IIP) prediction is performed based on the received position and velocity information. In preparation for ESA's Maxus-4 mission, a sounding rocket test flight was carried out at Esrange, Kiruna, on 19 Feb. 2001 to validate existing ground facilities and range safety installations. Due to the absence of a dedicated scientific payload, the flight offered the opportunity to test multiple GPS receivers and assess their performance for the tracking of sounding rockets. In addition to the ORION receiver, an Ashtech G12 HDMA receiver and a BAE (Canadian Marconi) Allstar receiver, both connected to a wrap-around antenna, have been flown on the same rocket as part of an independent experiment provided by the Goddard Space Flight Center. This allows an in-depth verification and trade-off of different receiver and antenna concepts.

  3. Subnanosecond GPS-based clock synchronization and precision deep-space tracking

    NASA Technical Reports Server (NTRS)

    Dunn, C. E.; Lichten, S. M.; Jefferson, D. C.; Border, J. S.

    1992-01-01

    Interferometric spacecraft tracking is accomplished by the Deep Space Network (DSN) by comparing the arrival time of electromagnetic spacecraft signals at ground antennas separated by baselines on the order of 8000 km. Clock synchronization errors within and between DSN stations directly impact the attainable tracking accuracy, with a 0.3-nsec error in clock synchronization resulting in an 11-nrad angular position error. This level of synchronization is currently achieved by observing a quasar which is angularly close to the spacecraft just after the spacecraft observations. By determining the differential arrival times of the random quasar signal at the stations, clock offsets and propagation delays within the atmosphere and within the DSN stations are calibrated. Recent developments in time transfer techniques may allow medium accuracy (50-100 nrad) spacecraft tracking without near-simultaneous quasar-based calibrations. Solutions are presented for a worldwide network of Global Positioning System (GPS) receivers in which the formal errors for DSN clock offset parameters are less than 0.5 nsec. Comparisons of clock rate offsets derived from GPS measurements and from very long baseline interferometry (VLBI), as well as the examination of clock closure, suggest that these formal errors are a realistic measure of GPS-based clock offset precision and accuracy. Incorporating GPS-based clock synchronization measurements into a spacecraft differential ranging system would allow tracking without near-simultaneous quasar observations. The impact on individual spacecraft navigation-error sources due to elimination of quasar-based calibrations is presented. System implementation, including calibration of station electronic delays, is discussed.

  4. The effect of tracking network configuration on GPS baseline estimates for the CASA Uno experiment

    NASA Technical Reports Server (NTRS)

    Wolf, S. Kornreich; Dixon, T. H.; Freymueller, J. T.

    1990-01-01

    The effect of the tracking network on long (greater than 100 km) GPS baseline estimates was estimated using various subsets of the global tracking network initiated by the first Central and South America (CASA Uno) experiment. It was found that best results could be obtained with a global tacking network consisting of three U.S. stations, two sites in the southwestern Pacific, and two sites in Europe. In comparison with smaller subsets, this global network improved the baseline repeatability, the resolution of carrier phase cycle ambiguities, and formal errors of the orbit estimates.

  5. The effect of tracking network configuration on GPS baseline estimates for the CASA Uno experiment

    NASA Technical Reports Server (NTRS)

    Wolf, S. Kornreich; Dixon, T. H.; Freymueller, J. T.

    1990-01-01

    The effect of the tracking network on long (greater than 100 km) GPS baseline estimates was estimated using various subsets of the global tracking network initiated by the first Central and South America (CASA Uno) experiment. It was found that best results could be obtained with a global tacking network consisting of three U.S. stations, two sites in the southwestern Pacific, and two sites in Europe. In comparison with smaller subsets, this global network improved the baseline repeatability, the resolution of carrier phase cycle ambiguities, and formal errors of the orbit estimates.

  6. Comparison of global positioning system (GPS) tracking and parent-report diaries to characterize children's time-location patterns.

    PubMed

    Elgethun, Kai; Yost, Michael G; Fitzpatrick, Cole T E; Nyerges, Timothy L; Fenske, Richard A

    2007-03-01

    Respondent error, low resolution, and study participant burden are known limitations of diary timelines used in exposure studies such as the National Human Exposure Assessment Survey (NHEXAS). Recent advances in global positioning system (GPS) technology have produced tracking devices sufficiently portable, functional and affordable to utilize in exposure assessment science. In this study, a differentially corrected GPS (dGPS) tracking device was compared to the NHEXAS diary timeline. The study also explored how GPS can be used to evaluate and improve such diary timelines by determining which location categories and which respondents are least likely to record "correct" time-location responses. A total of 31 children ages 3-5 years old wore a dGPS device for all waking hours on a weekend day while their parents completed the NHEXAS diary timeline to document the child's time-location pattern. Parents misclassified child time-location approximately 48% of the time using the NHEXAS timeline in comparison to dGPS. Overall concordance between methods was marginal (kappa=0.33-0.35). The dGPS device found that on average, children spent 76% of the 24-h study period in the home. The diary underestimated time the child spent in the home by 17%, while overestimating time spent inside other locations, outside at home, outside in other locations, and time spent in transit. Diary data for time spent outside at home and time in transit had the lowest response concordance with dGPS. The diaries of stay-at-home mothers and mothers working unskilled labor jobs had lower concordance with dGPS than did those of the other participants. The ability of dGPS tracking to collect continuous rather than categorical (ordinal) data was also demonstrated. It is concluded that automated GPS tracking measurements can improve the quality and collection efficiency of time-location data in exposure assessment studies, albeit for small cohorts.

  7. Adaptive Kalman filtering methods for tracking GPS signals in high noise/high dynamic environments

    NASA Astrophysics Data System (ADS)

    Zuo, Qiyao; Yuan, Hong; Lin, Baojun

    2007-11-01

    GPS C/A signal tracking algorithms have been developed based on adaptive Kalman filtering theory. In the research, an adaptive Kalman filter is used to substitute for standard tracking loop filters. The goal is to improve estimation accuracy and tracking stabilization in high noise and high dynamic environments. The linear dynamics model and the measurements model are designed to estimate code phase, carrier phase, Doppler shift, and rate of change of Doppler shift. Two adaptive algorithms are applied to improve robustness and adaptive faculty of the tracking, one is Sage adaptive filtering approach and the other is strong tracking method. Both the new algorithms and the conventional tracking loop have been tested by using simulation data. In the simulation experiment, the highest jerk of the receiver is set to 10G m/s 3 with the lowest C/No 30dBHz. The results indicate that the Kalman filtering algorithms are more robust than the standard tracking loop, and performance of tracking loop using the algorithms is satisfactory in such extremely adverse circumstances.

  8. Deriving Animal Behaviour from High-Frequency GPS: Tracking Cows in Open and Forested Habitat

    PubMed Central

    de Weerd, Nelleke; van Langevelde, Frank; van Oeveren, Herman; Nolet, Bart A.; Kölzsch, Andrea; Prins, Herbert H. T.; de Boer, W. Fred

    2015-01-01

    The increasing spatiotemporal accuracy of Global Navigation Satellite Systems (GNSS) tracking systems opens the possibility to infer animal behaviour from tracking data. We studied the relationship between high-frequency GNSS data and behaviour, aimed at developing an easily interpretable classification method to infer behaviour from location data. Behavioural observations were carried out during tracking of cows (Bos Taurus) fitted with high-frequency GPS (Global Positioning System) receivers. Data were obtained in an open field and forested area, and movement metrics were calculated for 1 min, 12 s and 2 s intervals. We observed four behaviour types (Foraging, Lying, Standing and Walking). We subsequently used Classification and Regression Trees to classify the simultaneously obtained GPS data as these behaviour types, based on distances and turning angles between fixes. GPS data with a 1 min interval from the open field was classified correctly for more than 70% of the samples. Data from the 12 s and 2 s interval could not be classified successfully, emphasizing that the interval should be long enough for the behaviour to be defined by its characteristic movement metrics. Data obtained in the forested area were classified with a lower accuracy (57%) than the data from the open field, due to a larger positional error of GPS locations and differences in behavioural performance influenced by the habitat type. This demonstrates the importance of understanding the relationship between behaviour and movement metrics, derived from GNSS fixes at different frequencies and in different habitats, in order to successfully infer behaviour. When spatially accurate location data can be obtained, behaviour can be inferred from high-frequency GNSS fixes by calculating simple movement metrics and using easily interpretable decision trees. This allows for the combined study of animal behaviour and habitat use based on location data, and might make it possible to detect deviations

  9. Deriving Animal Behaviour from High-Frequency GPS: Tracking Cows in Open and Forested Habitat.

    PubMed

    de Weerd, Nelleke; van Langevelde, Frank; van Oeveren, Herman; Nolet, Bart A; Kölzsch, Andrea; Prins, Herbert H T; de Boer, W Fred

    2015-01-01

    The increasing spatiotemporal accuracy of Global Navigation Satellite Systems (GNSS) tracking systems opens the possibility to infer animal behaviour from tracking data. We studied the relationship between high-frequency GNSS data and behaviour, aimed at developing an easily interpretable classification method to infer behaviour from location data. Behavioural observations were carried out during tracking of cows (Bos Taurus) fitted with high-frequency GPS (Global Positioning System) receivers. Data were obtained in an open field and forested area, and movement metrics were calculated for 1 min, 12 s and 2 s intervals. We observed four behaviour types (Foraging, Lying, Standing and Walking). We subsequently used Classification and Regression Trees to classify the simultaneously obtained GPS data as these behaviour types, based on distances and turning angles between fixes. GPS data with a 1 min interval from the open field was classified correctly for more than 70% of the samples. Data from the 12 s and 2 s interval could not be classified successfully, emphasizing that the interval should be long enough for the behaviour to be defined by its characteristic movement metrics. Data obtained in the forested area were classified with a lower accuracy (57%) than the data from the open field, due to a larger positional error of GPS locations and differences in behavioural performance influenced by the habitat type. This demonstrates the importance of understanding the relationship between behaviour and movement metrics, derived from GNSS fixes at different frequencies and in different habitats, in order to successfully infer behaviour. When spatially accurate location data can be obtained, behaviour can be inferred from high-frequency GNSS fixes by calculating simple movement metrics and using easily interpretable decision trees. This allows for the combined study of animal behaviour and habitat use based on location data, and might make it possible to detect deviations

  10. Automated time activity classification based on global positioning system (GPS) tracking data

    PubMed Central

    2011-01-01

    Background Air pollution epidemiological studies are increasingly using global positioning system (GPS) to collect time-location data because they offer continuous tracking, high temporal resolution, and minimum reporting burden for participants. However, substantial uncertainties in the processing and classifying of raw GPS data create challenges for reliably characterizing time activity patterns. We developed and evaluated models to classify people's major time activity patterns from continuous GPS tracking data. Methods We developed and evaluated two automated models to classify major time activity patterns (i.e., indoor, outdoor static, outdoor walking, and in-vehicle travel) based on GPS time activity data collected under free living conditions for 47 participants (N = 131 person-days) from the Harbor Communities Time Location Study (HCTLS) in 2008 and supplemental GPS data collected from three UC-Irvine research staff (N = 21 person-days) in 2010. Time activity patterns used for model development were manually classified by research staff using information from participant GPS recordings, activity logs, and follow-up interviews. We evaluated two models: (a) a rule-based model that developed user-defined rules based on time, speed, and spatial location, and (b) a random forest decision tree model. Results Indoor, outdoor static, outdoor walking and in-vehicle travel activities accounted for 82.7%, 6.1%, 3.2% and 7.2% of manually-classified time activities in the HCTLS dataset, respectively. The rule-based model classified indoor and in-vehicle travel periods reasonably well (Indoor: sensitivity > 91%, specificity > 80%, and precision > 96%; in-vehicle travel: sensitivity > 71%, specificity > 99%, and precision > 88%), but the performance was moderate for outdoor static and outdoor walking predictions. No striking differences in performance were observed between the rule-based and the random forest models. The random forest model was fast and easy to execute

  11. The usefulness of GPS bicycle tracking data for evaluating the impact of infrastructure change on cycling behaviour.

    PubMed

    Heesch, Kristiann C; Langdon, Michael

    2016-09-01

    Issue addressed: A key strategy to increase active travel is the construction of bicycle infrastructure. Tools to evaluate this strategy are limited. This study assessed the usefulness of a smartphone GPS tracking system for evaluating the impact of this strategy on cycling behaviour.Methods: Cycling usage data were collected from Queenslanders who used a GPS tracking app on their smartphone from 2013-2014. 'Heat' and volume maps of the data were reviewed, and GPS bicycle counts were compared with surveillance data and bicycle counts from automatic traffic-monitoring devices.Results: Heat maps broadly indicated that changes in cycling occurred near infrastructure improvements. Volume maps provided changes in counts of cyclists due to these improvements although errors were noted in geographic information system (GIS) geo-coding of some GPS data. Large variations were evident in the number of cyclists using the app in different locations. These variations limited the usefulness of GPS data for assessing differences in cycling across locations.Conclusion: Smartphone GPS data are useful in evaluating the impact of improved bicycle infrastructure in one location. Using GPS data to evaluate differential changes in cycling across multiple locations is problematic when there is insufficient traffic-monitoring devices available to triangulate GPS data with bicycle traffic count data.So what?: The use of smartphone GPS data with other data sources is recommended for assessing how infrastructure improvements influence cycling behaviour.

  12. Modeling long-term collider performance

    SciTech Connect

    Ritson, D. Superconducting Super Collider Lab., Dallas, TX )

    1991-07-01

    A model for the SSC arcs is described with multipole lattice field errors agglomerated into 32 lattice points, and with first order lattice errors and modulation provided by discrete transfer elements. Numerical solutions for long term dynamic aperture studies are obtained by multipole kick-drift tracking. The CPU time required to track through one turn is minimal, and comparable to that required to implement a one-turn fifth-order Taylor series map. Comparisons with tracking results using a fine grained representation of the lattice are made, and found to be satisfactory. The effects of tune modulation are studied and can substantially degrade long-term dynamic aperture. The effects of small relativistic momentum corrections, usually neglected for the large momenta at the SSC, are shown to have negligible influence on tracking results. 5 refs., 7 figs.

  13. Long-Term Stability of Social Participation

    ERIC Educational Resources Information Center

    Hyyppa, Markku T.; Maki, Juhani; Alanen, Erkki; Impivaara, Olli; Aromaa, Arpo

    2008-01-01

    The long-term stability of social participation was investigated in a representative urban population of 415 men and 579 women who had taken part in the nationwide Mini-Finland Health Survey in the years 1978-1980 and were re-examined 20 years later. Stability was assessed by means of the following tracking coefficients: kappa, proportion of…

  14. Optimization of the effective GPS data rate

    NASA Technical Reports Server (NTRS)

    Mcintyre, David S.

    1990-01-01

    Ohio University's Avionics Engineering Center is performing research directed towards the integration of the NAVSTAR Global Positioning System (GPS) and the Inertial Navigation System (INS) for attitude and heading determination. The integration of GPS/INS offers synergistic benefits. INS gyro drift error can be compensated by the long-term stability of GPS by means of an in-flight data monitoring algorithm. Using GPS data as a reference is more advantageous than implementing an additional INS since GPS offers a dissimilar redundancy to the attitude and heading determination configuration. In converse, the short-term stability of the INS can be used to correct or substitute for faulty GPS data due to tracking loop phase lag or data gaps because of satellite shielding. The optimization of the effective GPS data rate is essential for the proper execution of an integrated GPS/INS in-flight algorithm. GPS attitude and heading information must be consistently available during INS outages. Present research efforts involve the development of an in-flight algorithm that maximizes the potential of integrated GPS/INS. This algorithm determines the acceptable limits of phase lag that the GPS tracking loop introduces to the flight control system (FCS) during the transmission of information. Once these calculated limits are exceeded, INS data are used to insure the continuous availability of attitude and heading information to the flight control system.

  15. Beyond the usual mapping functions in GPS, VLBI and Deep Space tracking.

    NASA Astrophysics Data System (ADS)

    Barriot, Jean-Pierre; Serafini, Jonathan; Sichoix, Lydie

    2014-05-01

    We describe here a new algorithm to model the water contents of the atmosphere (including ZWD) from GPS slant wet delays relative to a single receiver. We first make the assumption that the water vapor contents are mainly governed by a scale height (exponential law), and secondly that the departures from this decaying exponential can be mapped as a set of low degree 3D Zernike functions (w.r.t. space) and Tchebyshev polynomials (w.r.t. time.) We compare this new algorithm with previous algorithms known as mapping functions in GPS, VLBI and Deep Space tracking and give an example with data acquired over a one day time span at the Geodesy Observatory of Tahiti.

  16. Dendritic morphogenesis of cerebellar Purkinje cells through extension and retraction revealed by long-term tracking of living cells in vitro.

    PubMed

    Tanaka, M; Yanagawa, Y; Obata, K; Marunouchi, T

    2006-08-25

    Cerebellar Purkinje cells have the most elaborate dendritic trees among the neurons in the CNS. To investigate the dynamic aspects of dendritic morphogenesis of Purkinje cells, we performed a long-term analysis of living cells in cerebellar cell cultures derived from glutamate decarboxylase 67-green fluorescent protein mice. Most Purkinje cells had several primary dendrites during the 25-day culture period. Repeated observation of green fluorescent protein-expressing Purkinje cells over a period of 10-25 days in vitro demonstrated that not only extension, but also retraction of primary dendrites occurred during this culture period. Interestingly, both extension and retraction of primary dendrites were active between 10 and 15 days in vitro, and retraction of a primary dendrite occurred concomitantly with elongation of other primary dendrites in the same cell. Analysis of the morphological characteristics of the retracted primary dendrites demonstrated that shorter and less branched primary dendrites tended to retract. Furthermore, treatment with an inhibitor of calcium/calmodulin-dependent protein kinase II reduced the number of primary dendrites specifically during 5-15 days in vitro, the culture period when the extension and retraction of primary dendrites occurred actively. Blockade of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/kainate-type glutamate receptors also reduced the number of primary dendrites during the same culture period, while inhibition of glutamate transporters increased the number. These findings suggest that the final morphology of Purkinje cells is achieved not only through extension, but also through retraction of their dendrites, and that calcium/calmodulin-dependent protein kinase II and neuronal activity are involved in this dendritic morphogenesis.

  17. An analysis of the operational GFS simplified Arakawa Schubert parameterization within a WRF framework: A Hurricane Sandy (2012) long-term track forecast perspective

    NASA Astrophysics Data System (ADS)

    Bassill, Nick P.

    2015-01-01

    Sandy (2012) is known as an incredibly destructive storm and one defined meteorologically by its large size, and its significant forecast track spreads among various operational models roughly 1 week before landfall. While the operational European Centre for Medium-Range Weather Forecasts model accurately depicted a northeastern United States landfall, the Global Forecasting System (GFS) model consistently forecast a track toward the North Atlantic Ocean. Using a Weather Research and Forecasting (WRF) model framework, Bassill suggested that these differences were primarily a function of differences between the two models' cumulus parameterization (CP). This study also uses a WRF model framework to examine the simplified Arakawa Schubert CP used in the GFS model. It is found that increasing the deep convective entrainment coefficient produces more realistic forecast tracks for forecasts initialized roughly 1 week before landfall. This occurs through a reorientation of the precipitation (and associated latent heating) around Sandy during a critical time period in which it was interacting with a series of upper troughs to its west and northwest. Reorienting the latent heating reshapes the upper tropospheric steering pattern toward the one that is more negatively tilted and consistent with observations.

  18. Inertial and GPS data integration for positioning and tracking of GPR

    NASA Astrophysics Data System (ADS)

    Chicarella, Simone; D'Alvano, Alessandro; Ferrara, Vincenzo; Frezza, Fabrizio; Pajewski, Lara

    2015-04-01

    Nowadays many applications and studies use a Global Positioning System (GPS) to integrate Ground-Penetrating Radar (GPR) data [1-2]. The aim is the production of detailed detection maps that are geo-referenced and superimposable on geographic maps themes. GPS provides data to determine static positioning, and to track the mobile detection system path on the land. A low-cost standard GPS, like GPS-622R by RF Solutions Ltd, allows accuracy around 2.5 m CEP (Circular Error Probability), and a maximum update rate of 10 Hz. These accuracy and update rate are satisfying values when we evaluate positioning datum, but they are unsuitable for precision tracking of a speedy-mobile GPR system. In order to determine the relative displacements with respect to an initial position on the territory, an Inertial Measurement Unit (IMU) can be used. Some inertial-system applications for GPR tracking have been presented in recent studies [3-4]. The integration of both GPS and IMU systems is the aim of our work, in order to increase GPR applicability, e.g. the case of a GPR mounted on an unmanned aerial vehicle for the detection of people buried under avalanches [5]. In this work, we will present the design, realization and experimental characterization of our electronic board that includes GPS-622R and AltIMU-10 v3 by Pololu. The latter comprises an inertial-measurement unit and an altimeter. In particular, the IMU adopts L3GD20 gyro and LSM303D accelerometer and magnetometer; the digital barometer LPS331AP provides data for altitude evaluation. The prototype of our system for GPR positioning and tracking is based on an Arduino microcontroller board. Acknowledgement This work benefited from networking activities carried out within the EU funded COST Action TU1208 'Civil Engineering Applications of Ground Penetrating Radar. ' References [1] M. Solla, X. Núñez-Nieto, M. Varela-González, J. Martínez-Sánchez, and P. Arias, 'GPR for Road Inspection: georeferencing and efficient

  19. Fine-scale tracking of marine turtles using GPS-Argos PTTs.

    PubMed

    Yasuda, Tohya; Arai, Nobuaki

    2005-05-01

    High-accuracy location data of wildlife telemetry using conventional satellite location systems are difficult to obtain. However, such data are necessary to clarify the nature of movements and home range sizes of animals. In order to measure the high-accuracy location data, we developed new GPS-Argos Platform Terminal Transmitters (PTTs) which transmit both the conventional location and GPS location simultaneously. Two experiments, one in an artificial rearing pond and the other in the open sea, were performed. First, two hawksbill turtles were tracked with the PTTs in a 5 ha breeding pond in Thailand. Their home ranges using both data were calculated and found to be 2.96 ha and 0.93 ha by the GPS data, and 156,740 ha and 184,478 ha by a conventional data. Secondly, a female green turtle attached with the GPS-Argos was released from the coast of Pangnga Province, Thailand. There was a relationship between depth and speed of travel based on the GPS data. The data from the PTT showed that the turtle moved south along the coastline at the depth of less than 20 m for 5 days, and then stayed at a depth of less than 10 m for 4 days. However, we could not find any clear relationship using conventional data. Only a meandering movement at a variety of depths was observed. The results of the two experiments indicated the PTTs have an enormous potential for enhancing our understanding of fine-scale movement patterns and home ranges of marine turtles.

  20. Tracking magma volume recovery at okmok volcano using GPS and an unscented kalman filter

    USGS Publications Warehouse

    Fournier, T.; Freymueller, Jeffrey T.; Cervelli, Peter

    2009-01-01

    Changes beneath a volcano can be observed through position changes in a GPS network, but distinguishing the source of site motion is not always straightforward. The records of continuous GPS sites provide a favorable data set for tracking magma migration. Dense campaign observations usually provide a better spatial picture of the overall deformation field, at the expense of an episodic temporal record. Combining these observations provides the best of both worlds. A Kalman filter provides a means for integrating discrete and continuous measurements and for interpreting subtle signals. The unscented Kalman filter (UKF) is a nonlinear method for time-dependent observations. We demonstrate the application of this technique to deformation data by applying it to GPS data collected at Okmok volcano. Seven years of GPS observations at Okmok are analyzed using a Mogi source model and the UKF. The deformation source at Okmok is relatively stable at 2.5 km depth below sea level, located beneath the center of the caldera, which means the surface deformation is caused by changes in the strength of the source. During the 7 years of GPS observations more than 0.5 m of uplift has occurred, a majority of that during the time period January 2003 to July 2004. The total volume recovery at Okmok since the last eruption in 1997 is ??60-80%. The UKF allows us to solve simultaneously for the time-dependence of the source strength and for the location without a priori information about the source. ?? 2009 by the American Geophysical Union.

  1. Long-term testing

    SciTech Connect

    Ferber, M.; Graves, G.A. Jr.

    1994-12-31

    Land-based gas turbines are significantly different from automotive gas turbines in that they are designed to operate for 50,000 h or greater (compared to 5,000--10,000 h). The primary goal of this research is to determine the long-term survivability of ceramic materials for industrial gas turbine applications. Research activities in this program focus on the evaluation of the static tensile creep and stress rupture (SR) behavior of three commercially available structural ceramics which have been identified by the gas turbine manufacturers as leading candidates for use in industrial gas turbines. For each material investigated, a minimum of three temperatures and four stresses will be used to establish the stress and temperature sensitivities of the creep and SR behavior. Because existing data for many candidate structural ceramics are limited to testing times less than 2,000 h, this program will focus on extending these data to times on the order of 10,000 h, which represents the lower limit of operating time anticipated for ceramic blades and vanes in gas turbine engines. A secondary goal of the program will be to investigate the possibility of enhancing life prediction estimates by combining interrupted tensile SR tests and tensile dynamic fatigue tests in which tensile strength is measured as a function of stressing rate. The third goal of this program will be to investigate the effects of water vapor upon the SR behavior of the three structural ceramics chosen for the static tensile studies by measuring the flexural strength as a function of stressing rate at three temperatures.

  2. Flight Performance Evaluation of Three GPS Receivers for Sounding Rocket Tracking

    NASA Technical Reports Server (NTRS)

    Bull, Barton; Diehl, James; Montenbruck, Oliver; Markgraf, Markus; Bauer, Frank (Technical Monitor)

    2001-01-01

    In preparation for the European Space Agency Maxus-4 mission, a sounding rocket test flight was carried out at Esrange,, near Kiruna, Sweden on February 19, 2001 to validate existing ground facilities and range safety installations. Due to the absence of a dedicated scientific payload, the flight offered the opportunity to test multiple GPS receivers and assess their performance for the tracking of sounding rockets. The receivers included an Ashtech G12 HDMA receiver, a BAE (Canadian Marconi) Allstar receiver and a Mitel Orion receiver. All of them provide CIA code tracking on the L1 frequency to determine the user position and make use of Doppler measurements to derive the instantaneous velocity. Among the receivers, the G12 has been optimized for use under highly dynamic conditions and has earlier been flown successfully on NASA sounding rockets [Bull, ION-GPS-2000]. The Allstar is representative of common single frequency receivers for terrestrial applications and received no particular modification, except for the disabling of the common altitude and velocity constraints that would otherwise inhibit its use for space application. The Orion receiver, finally, employs the same Mitel chipset as the Allstar, but has received various firmware modifications by DLR to safeguard it against signal losses and improve its tracking performance [Montenbruck et al., ION-GPS-2000]. While the two NASA receivers were driven by a common wrap-around antenna, the DLR experiment made use of a switchable antenna system comprising a helical antenna in the tip of the rocket and two blade antennas attached to the body of the vehicle. During the boost a peak acceleration of roughly 17g's was achieved which resulted in a velocity of about 1100 m/s at the end of the burn. At apogee, the rocket reached a maximum altitude of over 80 km. A detailed analysis of the attained flight data will be given in the paper together with a evaluation of different receiver designs and antenna concepts.

  3. Flight Performance Evaluation of Three GPS Receivers for Sounding Rocket Tracking

    NASA Technical Reports Server (NTRS)

    Bull, Barton; Diehl, James; Montenbruck, Oliver; Markgraf, Markus; Bauer, Frank (Technical Monitor)

    2001-01-01

    In preparation for the European Space Agency Maxus-4 mission, a sounding rocket test flight was carried out at Esrange,, near Kiruna, Sweden on February 19, 2001 to validate existing ground facilities and range safety installations. Due to the absence of a dedicated scientific payload, the flight offered the opportunity to test multiple GPS receivers and assess their performance for the tracking of sounding rockets. The receivers included an Ashtech G12 HDMA receiver, a BAE (Canadian Marconi) Allstar receiver and a Mitel Orion receiver. All of them provide CIA code tracking on the L1 frequency to determine the user position and make use of Doppler measurements to derive the instantaneous velocity. Among the receivers, the G12 has been optimized for use under highly dynamic conditions and has earlier been flown successfully on NASA sounding rockets [Bull, ION-GPS-2000]. The Allstar is representative of common single frequency receivers for terrestrial applications and received no particular modification, except for the disabling of the common altitude and velocity constraints that would otherwise inhibit its use for space application. The Orion receiver, finally, employs the same Mitel chipset as the Allstar, but has received various firmware modifications by DLR to safeguard it against signal losses and improve its tracking performance [Montenbruck et al., ION-GPS-2000]. While the two NASA receivers were driven by a common wrap-around antenna, the DLR experiment made use of a switchable antenna system comprising a helical antenna in the tip of the rocket and two blade antennas attached to the body of the vehicle. During the boost a peak acceleration of roughly 17g's was achieved which resulted in a velocity of about 1100 m/s at the end of the burn. At apogee, the rocket reached a maximum altitude of over 80 km. A detailed analysis of the attained flight data will be given in the paper together with a evaluation of different receiver designs and antenna concepts.

  4. High-Resolution Positional Tracking for Long-Term Analysis of Drosophila Sleep and Locomotion Using the “Tracker” Program

    PubMed Central

    Slawson, Justin B.; Vecsey, Christopher G.; Huber, Robert; Griffith, Leslie C.

    2012-01-01

    Drosophila melanogaster has been used for decades in the study of circadian behavior, and more recently has become a popular model for the study of sleep. The classic method for monitoring fly activity involves counting the number of infrared beam crosses in individual small glass tubes. Incident recording methods such as this can measure gross locomotor activity, but they are unable to provide details about where the fly is located in space and do not detect small movements (i.e. anything less than half the enclosure size), which could lead to an overestimation of sleep and an inaccurate report of the behavior of the fly. This is especially problematic if the fly is awake, but is not moving distances that span the enclosure. Similarly, locomotor deficiencies could be incorrectly classified as sleep phenotypes. To address these issues, we have developed a locomotor tracking technique (the “Tracker” program) that records the exact location of a fly in real time. This allows for the detection of very small movements at any location within the tube. In addition to circadian locomotor activity, we are able to collect other information, such as distance, speed, food proximity, place preference, and multiple additional parameters that relate to sleep structure. Direct comparisons of incident recording and our motion tracking application using wild type and locomotor-deficient (CASK-β null) flies show that the increased temporal resolution in the data from the Tracker program can greatly affect the interpretation of the state of the fly. This is especially evident when a particular condition or genotype has strong effects on the behavior, and can provide a wealth of information previously unavailable to the investigator. The interaction of sleep with other behaviors can also be assessed directly in many cases with this method. PMID:22615954

  5. GPS Sounding Rocket Development at NASA with Simultaneous Multi-Payload Tracking Application

    NASA Technical Reports Server (NTRS)

    Bull, Barton; Martel, Hugh

    2000-01-01

    An inverse differential GPS system has been developed for Sounding Rocket use which includes the flight unit and a ground station capable of extracting GPS data from sounding rocket telemetry, performing a real time differential solution and graphically displaying the rocket's path relative to a predicted trajectory plot. Accuracy has been proven to within less than 10 meters. Postprocessing has increased the precision to within 10 - 20 centimeters. The system has been successfully flown several times and delivered to the Sounding Program Office for routine field use. In addition to providing position, velocity and time GPS data has been used on sounding rockets for vehicle performance analysis, effecting a one hundred fold improvement in data time tagging, and steering an optical tracking device to intercept payloads launched from over the horizon. Precise velocity separation information and timing has been provided to multiple payload systems. Future plans include its use for Range Safety and enabling of interferometric techniques. The technology and software developed also has potential application to small satellite navigation and formation flying.

  6. GPS tracking devices reveal foraging strategies of black-legged kittiwakes

    USGS Publications Warehouse

    Kotzerka, Jana; Garthe, Stefan; Hatch, Scott A.

    2010-01-01

    The Black-legged Kittiwake Rissa tridactyla is the most abundant gull species in the world, but some populations have declined in recent years, apparently due to food shortage. Kittiwakes are surface feeders and thus can compensate for low food availability only by increasing their foraging range and/or devoting more time to foraging. The species is widely studied in many respects, but long-distance foraging and the limitations of conventional radio telemetry have kept its foraging behavior largely out of view. The development of Global Positioning System (GPS) loggers is advancing rapidly. With devices as small as 8 g now available, it is possible to use this technology for tracking relatively small species of oceanic birds like kittiwakes. Here we present the first results of GPS telemetry applied to Black-legged Kittiwakes in 2007 in the North Pacific. All but one individual foraged in the neritic zone north of the island. Three birds performed foraging trips only close to the colony (within 13 km), while six birds had foraging ranges averaging about 40 km. The maximum foraging range was 59 km, and the maximum distance traveled was 165 km. Maximum trip duration was 17 h (mean 8 h). An apparently bimodal distribution of foraging ranges affords new insight on the variable foraging behaviour of Black-legged Kittiwakes. Our successful deployment of GPS loggers on kittiwakes holds much promise for telemetry studies on many other bird species of similar size and provides an incentive for applying this new approach in future studies.

  7. Impact of magnetic labeling on human and mouse stem cells and their long-term magnetic resonance tracking in a rat model of Parkinson disease.

    PubMed

    Stroh, Albrecht; Boltze, Johannes; Sieland, Katharina; Hild, Katharina; Gutzeit, Cindy; Jung, Tobias; Kressel, Jenny; Hau, Susann; Reich, Doreen; Grune, Tilman; Zimmer, Claus

    2009-01-01

    Magnetic resonance imaging (MRI) of magnetically labeled stem cells has become a valuable tool in the understanding and evaluation of experimental stem cell-based therapies of degenerative central nervous system disorders. This comprehensive study assesses the impact of magnetic labeling of both human and rodent stem cell-containing populations on multiple biologic parameters as maintenance of stemness and oxidative stress levels. Cells were efficiently magnetically labeled with very small superparamagnetic iron oxide particles. Only under the condition of tailored labeling strategies can the impact of magnetic labeling on vitality, proliferation, pluripotency, and oxidative stress levels be minimized. In a rat model of Parkinson disease, magnetically labeled mouse embryonic stem cells were tracked by high-field MRI for 6 months. Significant interindividual differences concerning the spatial distribution of cells became evident. Histologically, transplanted green fluorescent protein-positive iron oxide-labeled cells were clearly identified. No significant increase in oxidative stress levels at the implantation site and no secondary uptake of magnetic label by host phagocytotic cells were observed. Our study strongly suggests that molecular MRI approaches must be carefully tailored to the respective cell population to exert minimal physiologic impact, ensuring the feasibility of this imaging approach for clinical applications.

  8. Performance enhancement for a GPS vector-tracking loop utilizing an adaptive iterated extended Kalman filter.

    PubMed

    Chen, Xiyuan; Wang, Xiying; Xu, Yuan

    2014-12-09

    This paper deals with the problem of state estimation for the vector-tracking loop of a software-defined Global Positioning System (GPS) receiver. For a nonlinear system that has the model error and white Gaussian noise, a noise statistics estimator is used to estimate the model error, and based on this, a modified iterated extended Kalman filter (IEKF) named adaptive iterated Kalman filter (AIEKF) is proposed. A vector-tracking GPS receiver utilizing AIEKF is implemented to evaluate the performance of the proposed method. Through road tests, it is shown that the proposed method has an obvious accuracy advantage over the IEKF and Adaptive Extended Kalman filter (AEKF) in position determination. The results show that the proposed method is effective to reduce the root-mean-square error (RMSE) of position (including longitude, latitude and altitude). Comparing with EKF, the position RMSE values of AIEKF are reduced by about 45.1%, 40.9% and 54.6% in the east, north and up directions, respectively. Comparing with IEKF, the position RMSE values of AIEKF are reduced by about 25.7%, 19.3% and 35.7% in the east, north and up directions, respectively. Compared with AEKF, the position RMSE values of AIEKF are reduced by about 21.6%, 15.5% and 30.7% in the east, north and up directions, respectively.

  9. Long-Term Monitoring of Waterborne Pathogens and Microbial Source Tracking Markers in Paired Agricultural Watersheds under Controlled and Conventional Tile Drainage Management

    PubMed Central

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A.; Gannon, Victor; Gottschall, Natalie; Jokinen, Cassandra C.; Jones, Tineke H.; Khan, Izhar U. H.; Marti, Romain; Sunohara, Mark D.; Topp, Edward

    2014-01-01

    Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization. PMID:24727274

  10. Tracking the turbidity maximum zone in the Loire Estuary (France) based on a long-term, high-resolution and high-frequency monitoring network

    NASA Astrophysics Data System (ADS)

    Jalón-Rojas, Isabel; Schmidt, Sabine; Sottolichio, Aldo; Bertier, Christine

    2016-04-01

    A unique dataset of turbidity from 7 years of continuous monitoring at six stations, distributed evenly along a 62-km long transect, is presented to discuss, for the first time, the present-day dynamics of the turbidity maximum zone (TMZ) in the Loire Estuary. This system is considered one of the largest macrotidal, hyper-turbid estuaries of the European coast, mainly as the result of intense engineering works in the last two centuries. Besides accurate TMZ tracking, from tidal to multi-annual time scales, the high temporal and spatial resolution of measurements allows us to address TMZ aspects scarcely reported in the literature on estuarine sedimentary dynamics. In the Loire Estuary, TMZ moves upstream during periods of low discharge and its upstream boundary may reach up to 62 km from the mouth. The TMZ displacement is faster during its downstream flushing by river floods than during its upstream migration by tidal pumping (respectively 1.6 km day-1 and 0.9 km day-1 during 2011). However, the expulsion of the TMZ from the upper reaches requires higher discharge levels than its installation (respective discharge thresholds of 497-1034 m3 s-1 and 300-360 m3 s-1). This is due to the presence of mobile mud remaining after the TMZ presence, as confirmed by clockwise turbidity-discharge hysteresis patterns. While the installation threshold barely varies over years, the expulsion threshold is higher during years with a more concentrated and persistent TMZ. The interannual variability of the TMZ concentration and persistence is explained by the water volume transported during the previous high discharge period and the duration of the low discharge period, respectively, as recently shown for the Gironde Estuary, leading to a better understanding of TMZ features in macrotidal estuaries. The summer-averaged river flow is introduced as a hydrological indicator of the upstream boundary of the TMZ. In the context of global change, these three discharge-based indicators of TMZ

  11. A Real Time Differential GPS Tracking System for NASA Sounding Rockets

    NASA Technical Reports Server (NTRS)

    Bull, Barton; Bauer, Frank (Technical Monitor)

    2000-01-01

    Sounding rockets are suborbital launch vehicles capable of carrying scientific payloads to several hundred miles in altitude. These missions return a variety of scientific data including: chemical makeup and physical processes taking place in the atmosphere, natural radiation surrounding the Earth, data on the Sun, stars, galaxies and many other phenomena. In addition, sounding rockets provide a reasonably economical means of conducting engineering tests for instruments and devices to be used on satellites and other spacecraft prior to their use in these more expensive missions. Typically around thirty of these rockets are launched each year, from established ranges at Wallops Island, Virginia; Poker Flat Research Range, Alaska; White Sands Missile Range, New Mexico and from a number of ranges outside the United States. Many times launches are conducted from temporary launch ranges in remote parts of the world requiring considerable expense to transport and operate tracking radars. In order to support these missions, an inverse differential GPS system has been developed. The flight system consists of a small, inexpensive receiver, a preamplifier and a wrap-around antenna. A rugged, compact, portable ground station extracts GPS data from the raw payload telemetry stream, performs a real time differential solution and graphically displays the rocket's path relative to a predicted trajectory plot. In addition to generating a real time navigation solution, the system has been used for payload recovery, timing, data timetagging, precise tracking of multiple payloads and slaving of optical tracking systems for over the horizon acquisition. This paper discusses, in detail, the flight and ground hardware, as well as data processing and operational aspects of the system, and provides evidence of the system accuracy.

  12. A Real Time Differential GPS Tracking System for NASA Sounding Rockets

    NASA Technical Reports Server (NTRS)

    Bull, Barton; Bauer, Frank (Technical Monitor)

    2000-01-01

    Sounding rockets are suborbital launch vehicles capable of carrying scientific payloads to several hundred miles in altitude. These missions return a variety of scientific data including: chemical makeup and physical processes taking place in the atmosphere, natural radiation surrounding the Earth, data on the Sun, stars, galaxies and many other phenomena. In addition, sounding rockets provide a reasonably economical means of conducting engineering tests for instruments and devices to be used on satellites and other spacecraft prior to their use in these more expensive missions. Typically around thirty of these rockets are launched each year, from established ranges at Wallops Island, Virginia; Poker Flat Research Range, Alaska; White Sands Missile Range, New Mexico and from a number of ranges outside the United States. Many times launches are conducted from temporary launch ranges in remote parts of the world requiring considerable expense to transport and operate tracking radars. In order to support these missions, an inverse differential GPS system has been developed. The flight system consists of a small, inexpensive receiver, a preamplifier and a wrap-around antenna. A rugged, compact, portable ground station extracts GPS data from the raw payload telemetry stream, performs a real time differential solution and graphically displays the rocket's path relative to a predicted trajectory plot. In addition to generating a real time navigation solution, the system has been used for payload recovery, timing, data timetagging, precise tracking of multiple payloads and slaving of optical tracking systems for over the horizon acquisition. This paper discusses, in detail, the flight and ground hardware, as well as data processing and operational aspects of the system, and provides evidence of the system accuracy.

  13. Long-term environmental stewardship.

    SciTech Connect

    Nagy, Michael David

    2010-08-01

    The purpose of this Supplemental Information Source Document is to effectively describe Long-Term Environmental Stewardship (LTES) at Sandia National Laboratories/New Mexico (SNL/NM). More specifically, this document describes the LTES and Long-Term Stewardship (LTS) Programs, distinguishes between the LTES and LTS Programs, and summarizes the current status of the Environmental Restoration (ER) Project.

  14. Long-term urethral catheterisation.

    PubMed

    Turner, Bruce; Dickens, Nicola

    This article discusses long-term urethral catheterisation, focusing on the relevant anatomy and physiology, indications for the procedure, catheter selection and catheter care. It is important that nurses have a good working knowledge of long-term catheterisation as the need for this intervention will increase with the rise in chronic health conditions and the ageing population.

  15. Presynaptic long-term plasticity

    PubMed Central

    Yang, Ying; Calakos, Nicole

    2013-01-01

    Long-term synaptic plasticity is a major cellular substrate for learning, memory, and behavioral adaptation. Although early examples of long-term synaptic plasticity described a mechanism by which postsynaptic signal transduction was potentiated, it is now apparent that there is a vast array of mechanisms for long-term synaptic plasticity that involve modifications to either or both the presynaptic terminal and postsynaptic site. In this article, we discuss current and evolving approaches to identify presynaptic mechanisms as well as discuss their limitations. We next provide examples of the diverse circuits in which presynaptic forms of long-term synaptic plasticity have been described and discuss the potential contribution this form of plasticity might add to circuit function. Finally, we examine the present evidence for the molecular pathways and cellular events underlying presynaptic long-term synaptic plasticity. PMID:24146648

  16. Identifying Mobility Types in Cognitively Heterogeneous Older Adults Based on GPS-Tracking: What Discriminates Best?

    PubMed

    Wettstein, Markus; Wahl, Hans-Werner; Shoval, Noam; Auslander, Gail; Oswald, Frank; Heinik, Jeremia

    2015-12-01

    Heterogeneity in older adults' mobility and its correlates have rarely been investigated based on objective mobility data and in samples including cognitively impaired individuals. We analyzed mobility profiles within a cognitively heterogeneous sample of N = 257 older adults from Israel and Germany based on GPS tracking technology. Participants were aged between 59 and 91 years (M = 72.9; SD = 6.4) and were either cognitively healthy (CH, n = 146), mildly cognitively impaired (MCI, n = 76), or diagnosed with an early-stage dementia of the Alzheimer's type (DAT, n = 35). Based on cluster analysis, we identified three mobility types ("Mobility restricted," "Outdoor oriented," "Walkers"), which could be predicted based on socio-demographic indicators, activity, health, and cognitive impairment status using discriminant analysis. Particularly demented individuals and persons with worse health exhibited restrictions in mobility. Our findings contribute to a better understanding of heterogeneity in mobility in old age.

  17. Behavioural plasticity in wintering Mediterranean ospreys revealed by stable isotopes analyses and GPS tracking.

    NASA Astrophysics Data System (ADS)

    Monti, Flavio; Robert, Aloïs; Dominici, Jean-Marie; Sforzi, Andrea; Triay Bagur, Rafel; Muñoz Navarro, Antoni; Guillou, Gaël; Bentaleb, Ilham; Duriez, Olivier

    2015-04-01

    To infer wintering ecology in Mediterranean ospreys (Pandion haliaetus) we relied on a dual and complementary approach, using both GPS tracking and multi stable isotope tracer approaches. A control sample of feathers from 80 individuals (mostly chicks) was collected over a large latitudinal gradient (from Lapland to Africa) to assess the variability of carbon, nitrogen and sulphur stable isotope ratios between breeding sites and habitat types across the Western Palearctic. Then, C, N and S isotopic compositions from an experimental set of 18 Mediterranean adults were examined to infer wintering ground locations and habitat types used during the inter-breeding period. Additionally, 12 adult ospreys were fitted with GPS devices and tracked during migration and the wintering season. By combining the two techniques we evidenced a partial migratory population with 41.7% of tagged individuals being resident and 58.3% that actually migrated. Ospreys spent the winter at temperate latitudes and showed a high plasticity in habitat selection. They made use of marine bays, coastal lagoons/marshland and inland freshwater sites. Movements and home range areas were reduced during the season. Wintering grounds were largely spread over the coasts of different countries of the basin, rather than concentrated in one single area. Such behavioural plasticity in the choice of location and habitat type suggests the implementing of broad-scale approaches for the protection of important areas for ospreys in winter. To contribute at assuring a right level of conservation of the osprey populations in the Mediterranean basin, a harmonization of the management protocols of wetland sites among countries is necessary.

  18. Re-creating daily mobility histories for health research from raw GPS tracks: Validation of a kernel-based algorithm using real-life data.

    PubMed

    Kestens, Yan; Thierry, Benoit; Chaix, Basile

    2016-07-01

    GPS tracking is increasingly used to document daily mobility, allowing refined analysis of daily exposures and health behaviour. Validation of algorithms processing raw GPS data to identify activity locations and trips are lacking. Propose novel ways to evaluate GPS processing algorithms data while validating an existing kernel-based algorithm with real-life GPS tracks. Seven-day GPS tracking and GPS-prompted recall interviews were conducted among 234 adult participants of the RECORD GPS Study. Raw GPS data was transformed using a kernel-based algorithm. Two match and nine mismatch configurations are analysed. Algorithm detection of activity locations and trips were validated. Some 95.8% of available GPS time was correctly classified as an activity location or a trip. The algorithm falsely identified a trip for 2.2% of the tracking time, and falsely identified an activity location 0.7% of time. Missed trips and missed activity locations counted for less than .4% of the time. The tested kernel-based algorithm provides histories of activity locations and trips that are highly concordant with GPS-prompted follow-up interviews. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Patterns of GPS tracks suggest nocturnal foraging by incubating Peruvian pelicans (Pelecanus thagus).

    PubMed

    Zavalaga, Carlos B; Dell'Omo, Giacomo; Becciu, Paolo; Yoda, Ken

    2011-01-01

    Most seabirds are diurnal foragers, but some species may also feed at night. In Peruvian pelicans (Pelecanus thagus), the evidence for nocturnal foraging is sparse and anecdotal. We used GPS-dataloggers on five incubating Peruvian pelicans from Isla Lobos de Tierra, Perú, to examine their nocturnality, foraging movements and activities patterns at sea. All instrumented pelicans undertook nocturnal trips during a 5-7 day tracking period. Eighty-seven percent of these trips (n = 13) were strictly nocturnal, whereas the remaining occurred during the day and night. Most birds departed from the island after sunset and returned a few hours after sunrise. Birds traveled south of the island for single-day trips at a maximum range of 82.8 km. Overall, 22% of the tracking period was spent at sea, whereas the remaining time was spent on the island. In the intermediate section of the trip (between inbound and outbound commutes), birds spent 77% of the trip time in floating bouts interspersed by short flying bouts, the former being on average three times longer than the latter. Taken together, the high sinuosity of the bird's tracks during floating bouts, the exclusively nocturnal trips of most individuals, and the fact that all birds returned to the island within a few hours after sunrise suggest that pelicans were actively feeding at night. The nocturnal foraging strategy of Peruvian pelicans may reduce food competition with the sympatric and strictly diurnal Guanay cormorants (Phalacrocorax bougainvillii), Peruvian boobies (Sula variegata) and Blue-footed boobies (S. nebouxii), which were present on the island in large numbers. Likewise, plankton bioluminescence might be used by pelicans as indirect cues to locate anchovies during their upward migration at night. The foraging success of pelicans at night may be enhanced by seizing prey close to the sea surface using a sit-and-wait strategy.

  20. Patterns of GPS Tracks Suggest Nocturnal Foraging by Incubating Peruvian Pelicans (Pelecanus thagus)

    PubMed Central

    Zavalaga, Carlos B.; Dell'Omo, Giacomo; Becciu, Paolo; Yoda, Ken

    2011-01-01

    Most seabirds are diurnal foragers, but some species may also feed at night. In Peruvian pelicans (Pelecanus thagus), the evidence for nocturnal foraging is sparse and anecdotal. We used GPS-dataloggers on five incubating Peruvian pelicans from Isla Lobos de Tierra, Perú, to examine their nocturnality, foraging movements and activities patterns at sea. All instrumented pelicans undertook nocturnal trips during a 5–7 day tracking period. Eighty-seven percent of these trips (n = 13) were strictly nocturnal, whereas the remaining occurred during the day and night. Most birds departed from the island after sunset and returned a few hours after sunrise. Birds traveled south of the island for single-day trips at a maximum range of 82.8 km. Overall, 22% of the tracking period was spent at sea, whereas the remaining time was spent on the island. In the intermediate section of the trip (between inbound and outbound commutes), birds spent 77% of the trip time in floating bouts interspersed by short flying bouts, the former being on average three times longer than the latter. Taken together, the high sinuosity of the bird's tracks during floating bouts, the exclusively nocturnal trips of most individuals, and the fact that all birds returned to the island within a few hours after sunrise suggest that pelicans were actively feeding at night. The nocturnal foraging strategy of Peruvian pelicans may reduce food competition with the sympatric and strictly diurnal Guanay cormorants (Phalacrocorax bougainvillii), Peruvian boobies (Sula variegata) and Blue-footed boobies (S. nebouxii), which were present on the island in large numbers. Likewise, plankton bioluminescence might be used by pelicans as indirect cues to locate anchovies during their upward migration at night. The foraging success of pelicans at night may be enhanced by seizing prey close to the sea surface using a sit-and-wait strategy. PMID:21647444

  1. Flight Performance Evaluation of Three GPS Receivers for Sounding Rocket Tracking

    NASA Technical Reports Server (NTRS)

    Bull, Barton; Diehl, James; Montenbruck, Oliver; Markgraf, Markus; Bauer, Frank (Technical Monitor)

    2002-01-01

    In preparation for the European Space Agency Maxus-4 mission, a sounding rocket test flight was carried out at Esrange, near Kiruna, Sweden on February 19, 2001 to validate existing ground facilities and range safety installations. Due to the absence of a dedicated scientific payload, the flight offered the opportunity to test multiple GPS receivers and assess their performance for the tracking of sounding rockets. The receivers included an Ashtech G12 HDMA receiver, a BAE (Canadian Marconi) Allstar receiver and a Mitel Orion receiver. All of them provide C/A code tracking on the L1 frequency to determine the user position and make use of Doppler measurements to derive the instantaneous velocity. Among the receivers, the G12 has been optimized for use under highly dynamic conditions and has earlier been flown successfully on NASA sounding rockets. The Allstar is representative of common single frequency receivers for terrestrial applications and received no particular modification, except for the disabling of the common altitude and velocity constraints that would otherwise inhibit its use for space application. The Orion receiver, finally, employs the same Mitel chipset as the Allstar, but has received various firmware modifications by DLR to safeguard it against signal losses and improve its tracking performance. While the two NASA receivers were driven by a common wrap-around antenna, the DLR experiment made use of a switchable antenna system comprising a helical antenna in the tip of the rocket and two blade antennas attached to the body of the vehicle. During the boost a peak acceleration of roughly l7g's was achieved which resulted in a velocity of about 1100 m/s at the end of the burn. At apogee, the rocket reached an altitude of over 80 km. A detailed analysis of the attained flight data is given together with a evaluation of different receiver designs and antenna concepts.

  2. High Precision and Real Time Tracking of Low Earth Orbiters With GPS: Case Studies With TOPEX/POSEIDON and EUVE

    NASA Technical Reports Server (NTRS)

    Yunck, Thomas P.; Bertiger, Winy I.; Gold, Kenn; Guinn, Joseph; Reichert, Angie; Watkins, Michael

    1995-01-01

    TOPEX/POSEIDON carries a dual-frequency 6 channel GPS receiver while EUVE has a 12 channel single frequency receiver. Flying at an altitude of 1334 km, TOPEX/POSEIDON performs precise ocean altimetry, which demands the highest possible accuracy in determining the radial orbit component in post-processing. Radial RMS accuracies of about 2 cm were realized using reduced dynamic tracking techniques. In this approach, orbit errors due to force are substantially reduced by exploiting the geometric strength of GPS to solve for a set of stochastic forces. On EUVE, the emphasis was on evaluating real time positioning techniques with a single frequency receiver. The capability for real time 3D accuracies of 15 m in the presence of Selective Availability was shown. This was validated by comparing to a post-processed differential GPS truth orbit believed accurate to about 1 m.!.

  3. Examining the spatial congruence between data obtained with a novel activity location questionnaire, continuous GPS tracking, and prompted recall surveys

    PubMed Central

    2013-01-01

    Background Place and health researchers are increasingly interested in integrating individuals’ mobility and the experience they have with multiple settings in their studies. In practice, however, few tools exist which allow for rapid and accurate gathering of detailed information on the geographic location of places where people regularly undertake activities. We describe the development and validation of a new activity location questionnaire which can be useful in accounting for multiple environmental influences in large population health investigations. Methods To develop the questionnaire, we relied on a literature review of similar data collection tools and on results of a pilot study wherein we explored content validity, test-retest reliability, and face validity. To estimate convergent validity, we used data from a study of users of a public bicycle share program conducted in Montreal, Canada in 2011. We examined the spatial congruence between questionnaire data and data from three other sources: 1) one-week GPS tracks; 2) activity locations extracted from the GPS tracks; and 3) a prompted recall survey of locations visited during the day. Proximity and convex hull measures were used to compare questionnaire-derived data and GPS and prompted recall survey data. Results In the sample, 75% of questionnaire-reported activity locations were located within 400 meters of an activity location recorded on the GPS track or through the prompted recall survey. Results from convex hull analyses suggested questionnaire activity locations were more concentrated in space than GPS or prompted-recall locations. Conclusions The new questionnaire has high convergent validity and can be used to accurately collect data on regular activity spaces in terms of locations regularly visited. The methods, measures, and findings presented provide new material to further study mobility in place and health research. PMID:24025119

  4. Long-term parenteral nutrition

    PubMed Central

    Ladefoged, Karin; Jarnum, Stig

    1978-01-01

    Nineteen patients (11 women and eight men) aged 20-68 received long-term parenteral nutrition, mostly at home, for six to 63 months (mean 19 months). Indications for LTPN were extensive, active Crohn's disease in three patients, intestinocutaneous fistulas in three, and short-bowel syndrome in the remaining 13 patients. Subclavian or intra-atrial (Broviac) catheters were most commonly used, for which the average life was four and seven months respectively. Complications of long-term parenteral nutrition included pneumothorax in four out of 48 subclavian vein punctures. Catheter-induced thrombosis of central veins was shown by phlebography 17 times in nine patients, and eight episodes of total occlusion occurred. Two of these patients had pulmonary infarction. Nineteen episodes of catheter sepsis occurred in 11 patients, but only one was fatal. Complications related to intestinal disease included intra-abdominal abscesses and intestinal fistulas, and disturbances of liver function. Five patients died, though in only two was death related to long-term parenteral nutrition. One of these patients died from catheter sepsis, the other had subdural haematoma possibly caused by anticoagulant treatment. Eight of the 14 surviving patients still needed parenteral nutrition. All received a disability pension, but six had an acceptable quality of life with almost normal social activities. Despite problems such as difficulties in maintaining standardised infusion programmes, it was concluded that long-term parenteral nutrition at home is practicable and consistent with an acceptable quality of life. ImagesFIG 2 PMID:98199

  5. A magnetic pulse does not affect homing pigeon navigation: a GPS tracking experiment.

    PubMed

    Holland, Richard; Filannino, Caterina; Gagliardo, Anna

    2013-06-15

    The cues by which homing pigeons are able to return to a home loft after displacement to unfamiliar release sites remain debated. A number of experiments in which migratory birds have been treated with a magnetic pulse have produced a disruption in their orientation, which argues that a ferrimagnetic sense is used for navigation in birds. One previous experiment has also indicated an effect of magnetic pulses on homing pigeon navigation, although with inconsistent results. Previous studies have shown that some magnetic-related information is transmitted by the trigeminal nerve to the brain in some bird species, including the homing pigeon. The function of this information is still unclear. It has been suggested that this information is important for navigation. Previous studies with trigeminal nerve lesioned homing pigeons have clearly shown that the lack of trigeminally mediated information, even if magnetic, is not crucial for homing performance. However, this result does not completely exclude the possibility that other ferrimagnetic receptors in the homing pigeon play a role in navigation. Additionally, recent studies on homing pigeons suggested the existence of a ferrimagnetic sense in a novel location presumably located in the inner ear (lagena). In the present study, we tested whether any ferrimagnetic magnetoreceptors, irrespective of their location in the bird's head, are involved in pigeons' homing. To do this, we treated homing pigeons with a strong magnetic pulse before release, tracked birds with GPS loggers and analyzed whether this treatment affected homing performance. In the single previous magnetic pulse experiment on homing pigeons, only initial orientation at a release site was considered and the results were inconsistent. We observed no effect of the magnetic pulse at any of the sites used on initial orientation, homing performance, tortuosity or track efficiency, which does not support a role for the ferrimagnetic sense in homing pigeon

  6. The Precise Orbit and the Challenge of Long Term Stability

    NASA Technical Reports Server (NTRS)

    Lemoine, Frank G.; Cerri, Luca; Otten, Michiel; Bertiger, William; Zelensky, Nikita; Willis, Pascal

    2012-01-01

    The computation of a precise orbit reference is a fundamental component of the altimetric measurement. Since the dawn of the modern altimeter age, orbit accuracy has been determined by the quality of the GPS, SLR, and DORIS tracking systems, the fidelity of the measurement and force models, and the choice of parameterization for the orbit solutions, and whether a dynamic or a reduced-dynamic strategy is used to calculate the orbits. At the start of the TOPEX mission, the inaccuracies in the modeling of static gravity, dynamic ocean tides, and the nonconservative forces dominated the orbit error budget. Much of the error due to dynamic mismodeling can be compensated by reduced-dynamic tracking techniques depending on the measurement system strength. In the last decade, the launch of the GRACE mission has eliminated the static gravity field as a concern, and the background force models and the terrestrial reference frame have been systematically refined. GPS systems have realized many improvements, including better modeling of the forces on the GPS spacecraft, large increases in the ground tracking network, and improved modeling of the GPS measurements. DORIS systems have achieved improvements through the use of new antennae, more stable monumentation, and of satellite receivers that can track multiple beacons, and as well as through improved modeling of the nonconservative forces. Many of these improvements have been applied in the new reprocessed time series of orbits produced for the ERS satellites, Envisat, TOPEX/Poseidon and the Jason satellites, and as well as for the most recent Cryosat-2 and HY2A. We now face the challenge of maintaining a stable orbit reference for these altimetric satellites. Changes in the time-variable gravity field of the Earth and how these are modelled have been shown to affect the orbit evolution, and the calibration of the altimetric data with tide gauges. The accuracy of the reference frame realizations, and their projection into

  7. Augmented Reality for Searching Potential Assets in Medan using GPS based Tracking

    NASA Astrophysics Data System (ADS)

    Muchtar, M. A.; Syahputra, M. F.; Syahputra, N.; Ashrafia, S.; Rahmat, R. F.

    2017-01-01

    Every city is required to introduce its variety of potential assets so that the people know how to utilize or to develop their area. Potential assets include infrastructure, facilities, people, communities, organizations, customs that affects the characteristics and the way of life in Medan. Due to lack of socialization and information, most of people in Medan only know a few parts of the assets. Recently, so many mobile apps provide search and mapping locations used to find the location of potential assets in user’s area. However, the available information, such as text and digital maps, sometimes do not much help the user clearly and dynamically. Therefore, Augmented Reality technology able to display information in real world vision is implemented in this research so that the information can be more interactive and easily understood by user. This technology will be implemented in mobile apps using GPS based tracking and define the coordinate of user’s smartphone as a marker so that it can help people dynamically and easily find the location of potential assets in the nearest area based on the direction of user’s view on camera.

  8. Comparing children's GPS tracks with geospatial proxies for exposure to junk food.

    PubMed

    Sadler, Richard C; Gilliland, Jason A

    2015-01-01

    Various geospatial techniques have been employed to estimate children's exposure to environmental cardiometabolic risk factors, including junk food. But many studies uncritically rely on exposure proxies which differ greatly from actual exposure. Misrepresentation of exposure by researchers could lead to poor decisions and ineffective policymaking. This study conducts a GIS-based analysis of GPS tracks--'activity spaces'--and 21 proxies for activity spaces (e.g. buffers, container approaches) for a sample of 526 children (ages 9-14) in London, Ontario, Canada. These measures are combined with a validated food environment database (including fast food and convenience stores) to create a series of junk food exposure estimates and quantify the errors resulting from use of different proxy methods. Results indicate that exposure proxies consistently underestimate exposure to junk foods by as much as 68%. This underestimation is important to policy development because children are exposed to more junk food than estimated using typical methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Altered orientation and flight paths of pigeons reared on gravity anomalies: a GPS tracking study.

    PubMed

    Blaser, Nicole; Guskov, Sergei I; Meskenaite, Virginia; Kanevskyi, Valerii A; Lipp, Hans-Peter

    2013-01-01

    The mechanisms of pigeon homing are still not understood, in particular how they determine their position at unfamiliar locations. The "gravity vector" theory holds that pigeons memorize the gravity vector at their home loft and deduct home direction and distance from the angular difference between memorized and actual gravity vector. However, the gravity vector is tilted by different densities in the earth crust leading to gravity anomalies. We predicted that pigeons reared on different gravity anomalies would show different initial orientation and also show changes in their flight path when crossing a gravity anomaly. We reared one group of pigeons in a strong gravity anomaly with a north-to-south gravity gradient, and the other group of pigeons in a normal area but on a spot with a strong local anomaly with a west-to-east gravity gradient. After training over shorter distances, pigeons were released from a gravitationally and geomagnetically normal site 50 km north in the same direction for both home lofts. As expected by the theory, the two groups of pigeons showed divergent initial orientation. In addition, some of the GPS-tracked pigeons also showed changes in their flight paths when crossing gravity anomalies. We conclude that even small local gravity anomalies at the birth place of pigeons may have the potential to bias the map sense of pigeons, while reactivity to gravity gradients during flight was variable and appeared to depend on individual navigational strategies and frequency of position updates.

  10. Altered Orientation and Flight Paths of Pigeons Reared on Gravity Anomalies: A GPS Tracking Study

    PubMed Central

    Blaser, Nicole; Guskov, Sergei I.; Meskenaite, Virginia; Kanevskyi, Valerii A.; Lipp, Hans-Peter

    2013-01-01

    The mechanisms of pigeon homing are still not understood, in particular how they determine their position at unfamiliar locations. The “gravity vector” theory holds that pigeons memorize the gravity vector at their home loft and deduct home direction and distance from the angular difference between memorized and actual gravity vector. However, the gravity vector is tilted by different densities in the earth crust leading to gravity anomalies. We predicted that pigeons reared on different gravity anomalies would show different initial orientation and also show changes in their flight path when crossing a gravity anomaly. We reared one group of pigeons in a strong gravity anomaly with a north-to-south gravity gradient, and the other group of pigeons in a normal area but on a spot with a strong local anomaly with a west-to-east gravity gradient. After training over shorter distances, pigeons were released from a gravitationally and geomagnetically normal site 50 km north in the same direction for both home lofts. As expected by the theory, the two groups of pigeons showed divergent initial orientation. In addition, some of the GPS-tracked pigeons also showed changes in their flight paths when crossing gravity anomalies. We conclude that even small local gravity anomalies at the birth place of pigeons may have the potential to bias the map sense of pigeons, while reactivity to gravity gradients during flight was variable and appeared to depend on individual navigational strategies and frequency of position updates. PMID:24194860

  11. Affordable Freight Logistics Transport Information Management Optimisation and Asset Tracking Solution Using Smartphone GPS Capabilities

    NASA Astrophysics Data System (ADS)

    Muna, Joseph T.; Prescott, Kevin

    2011-08-01

    Traditionally, freight transport and telematics solutions that exploit the GPS capabilities of in- vehicle devices to provide innovative Location Based Services (LBS) including track and trace transport systems have been the preserve of a select cluster of transport operators and organisations with the financial resources to develop the requisite custom software and hardware on which they are deployed. The average cost of outfitting a typical transport vehicle or truck with the latest Intelligent Transport System (ITS) increases the cost of the vehicle by anything from a couple to several thousand Euros, depending on the complexity and completeness of the solution. Though this does not generally deter large fleet transport owners since they typically get Return on Investment (ROI) based on economies of scale, it presents a barrier for the smaller independent entities that constitute the majority of freight transport operators [1].The North Sea Freight Intelligent Transport Solution (NS FRITS), a project co-funded by the European Commission Interreg IVB North Sea Region Programme, aims to make acquisition of such transport solutions easier for those organisations that cannot afford the expensive, bespoke systems used by their larger competitors.The project addresses transport security threats by developing a system capable of informing major actors along the freight logistics supply chain, of changing circumstances within the region's major transport corridors and between transport modes. The project also addresses issues of freight volumes, inter-modality, congestion and eco-mobility [2].

  12. Sample-Wise Aiding in GPS/INS Ultra-Tight Integration for High-Dynamic, High-Precision Tracking

    PubMed Central

    Kou, Yanhong; Zhang, Han

    2016-01-01

    By aiding GPS receiver tracking loops with INS estimates of signal dynamics, GPS/INS ultra-tight coupling can improve the navigation performance in challenging environments. Traditionally the INS data are injected into the loops once every loop update interval, which limits the levels of dynamics accommodated. This paper presents a sample-wise aiding method, which interpolates the aiding Doppler into each digital sample of the local signal to further eliminate the dynamic errors. The relationship between the tracking error and the aiding rate is derived analytically. Moreover, the effects of sample-wise aiding using linear and spline interpolations are simulated and compared with traditional aiding under different INS data update rates. Finally, extensive tests based on a digital IF (intermediate frequency) signal simulator and a software receiver validate the theoretical equations and demonstrate that the dynamic stress error can be significantly reduced by sample-wise aiding. PMID:27077858

  13. Open-loop GPS signal tracking at low elevation angles from a ground-based observation site

    NASA Astrophysics Data System (ADS)

    Beyerle, Georg; Zus, Florian

    2017-01-01

    A 1-year data set of ground-based GPS signal observations aiming at geometric elevation angles below +2° is analysed. Within the "GLESER" measurement campaign about 2600 validated setting events were recorded by the "OpenGPS" open-loop tracking receiver at an observation site located at 52.3808° N, 13.0642° E between January and December 2014. The measurements confirm the feasibility of open-loop signal tracking down to geometric elevation angles of -1 to -1.5° extending the corresponding closed-loop tracking range by up to 1°. The study is based on the premise that observations of low-elevation events by a ground-based receiver may serve as test cases for space-based radio occultation measurements, even if the latter proceed at a significantly faster temporal scale. The results support the conclusion that the open-loop Doppler model has negligible influence on the derived carrier frequency profile for strong signal-to-noise density ratios above about 30 dB Hz. At lower signal levels, however, the OpenGPS receiver's dual-channel design, which tracks the same signal using two Doppler models differing by 10 Hz, uncovers a notable bias. The repeat patterns of the GPS orbit traces in terms of azimuth angle reveal characteristic signatures in both signal amplitude and Doppler frequency with respect to the topography close to the observation site. Mean vertical refractivity gradients, extracted from ECMWF meteorological fields, correlate weakly to moderately with observed signal amplitude fluctuations at geometric elevation angles between +1 and +2°. Results from multiple phase screen simulations support the interpretation that these fluctuations are at least partly produced by atmospheric multipath; at negative elevation angles diffraction at the ground surface seems to contribute.

  14. Long-term data archiving

    SciTech Connect

    Moore, David Steven

    2009-01-01

    Long term data archiving has much value for chemists, not only to retain access to research and product development records, but also to enable new developments and new discoveries. There are some recent regulatory requirements (e.g., FDA 21 CFR Part 11), but good science and good business both benefit regardless. A particular example of the benefits of and need for long term data archiving is the management of data from spectroscopic laboratory instruments. The sheer amount of spectroscopic data is increasing at a scary rate, and the pressures to archive come from the expense to create the data (or recreate it if it is lost) as well as its high information content. The goal of long-term data archiving is to save and organize instrument data files as well as any needed meta data (such as sample ID, LIMS information, operator, date, time, instrument conditions, sample type, excitation details, environmental parameters, etc.). This editorial explores the issues involved in long-term data archiving using the example of Raman spectral databases. There are at present several such databases, including common data format libraries and proprietary libraries. However, such databases and libraries should ultimately satisfy stringent criteria for long term data archiving, including readability for long times into the future, robustness to changes in computer hardware and operating systems, and use of public domain data formats. The latter criterion implies the data format should be platform independent and the tools to create the data format should be easily and publicly obtainable or developable. Several examples of attempts at spectral libraries exist, such as the ASTM ANDI format, and the JCAMP-DX format. On the other hand, proprietary library spectra can be exchanged and manipulated using proprietary tools. As the above examples have deficiencies according to the three long term data archiving criteria, Extensible Markup Language (XML; a product of the World Wide Web

  15. GPS tracking data of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast.

    PubMed

    Stienen, Eric W M; Desmet, Peter; Aelterman, Bart; Courtens, Wouter; Feys, Simon; Vanermen, Nicolas; Verstraete, Hilbran; de Walle, Marc Van; Deneudt, Klaas; Hernandez, Francisco; Houthoofdt, Robin; Vanhoorne, Bart; Bouten, Willem; Buijs, Roland-Jan; Kavelaars, Marwa M; Müller, Wendt; Herman, David; Matheve, Hans; Sotillo, Alejandro; Lens, Luc

    2016-01-01

    In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5 million occurrences, recorded by 101 GPS trackers mounted on 75 Lesser Black-backed Gulls and 26 Herring Gulls breeding at the Belgian and Dutch coast. The trackers were developed by the University of Amsterdam Bird Tracking System (UvA-BiTS, http://www.uva-bits.nl). These automatically record and transmit bird movements, which allows us and others to study their habitat use and migration behaviour in great detail. Our bird tracking network is operational since 2013. It is funded for LifeWatch by the Hercules Foundation and maintained in collaboration with UvA-BiTS and the Flanders Marine Institute (VLIZ). The recorded data are periodically released in bulk as open data (http://dataset.inbo.be/bird-tracking-gull-occurrences), and are also accessible through CartoDB and the Global Biodiversity Information Facility (GBIF).

  16. GPS tracking data of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast

    PubMed Central

    Stienen, Eric W.M.; Desmet, Peter; Aelterman, Bart; Courtens, Wouter; Feys, Simon; Vanermen, Nicolas; Verstraete, Hilbran; de Walle, Marc Van; Deneudt, Klaas; Hernandez, Francisco; Houthoofdt, Robin; Vanhoorne, Bart; Bouten, Willem; Buijs, Roland-Jan; Kavelaars, Marwa M.; Müller, Wendt; Herman, David; Matheve, Hans; Sotillo, Alejandro; Lens, Luc

    2016-01-01

    Abstract In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5 million occurrences, recorded by 101 GPS trackers mounted on 75 Lesser Black-backed Gulls and 26 Herring Gulls breeding at the Belgian and Dutch coast. The trackers were developed by the University of Amsterdam Bird Tracking System (UvA-BiTS, http://www.uva-bits.nl). These automatically record and transmit bird movements, which allows us and others to study their habitat use and migration behaviour in great detail. Our bird tracking network is operational since 2013. It is funded for LifeWatch by the Hercules Foundation and maintained in collaboration with UvA-BiTS and the Flanders Marine Institute (VLIZ). The recorded data are periodically released in bulk as open data (http://dataset.inbo.be/bird-tracking-gull-occurrences), and are also accessible through CartoDB and the Global Biodiversity Information Facility (GBIF). PMID:26877689

  17. Tracking down a solution: exploring the acceptability and value of wearable GPS devices for older persons, individuals with a disability and their support persons.

    PubMed

    Williamson, Brittany; Aplin, Tammy; de Jonge, Desleigh; Goyne, Matthew

    2017-11-01

    To explore the acceptability and value of three wearable GPS devices for older persons and individuals with a disability and safety concerns when accessing the community. This pilot study explored six wearers' and their support persons' experience of using three different wearable GPS devices (a pendant, watch, and mini GPS phone), each for a two-week period. Participants identified safety as the main value of using a wearable GPS device. The acceptability and value of these devices was strongly influenced by device features, ease of use, cost, appearance, the reliability of the GPS coordinates, the wearer's health condition and the users familiarity with technology. Overall, participants indicated that they preferred the pendant. Wearable GPS devices are potentially useful in providing individuals who have safety concerns with reassurance and access to assistance as required. To ensure successful utilization, future device design and device selection should consider the user's familiarity with technology and their health condition. This study also revealed that not all wearable GPS devices provide continuous location tracking. It is therefore critical to ensure that the device's location tracking functions address the wearer's requirements and reason for using the device. Implications for Rehabilitation The acceptability and usability of wearable GPS devices is strongly influenced by the device features, ease of use, cost, appearance, the reliability of the device to provide accurate and timely GPS coordinates, as well as the health condition of the wearer and their familiarity with technology. Wearable GPS devices need to be simple to use and support and training is essential to ensure they are successfully utilized. Not all wearable GPS devices provide continuous location tracking and accuracy of location is impacted by line of sight to satellites. Therefore, care needs to be taken when choosing a suitable device, to ensure that the device's location tracking

  18. Evaluation of micro-GPS receivers for tracking small-bodied mammals

    PubMed Central

    Shipley, Lisa A.; Forbey, Jennifer S.; Olsoy, Peter J.

    2017-01-01

    GPS telemetry markedly enhances the temporal and spatial resolution of animal location data, and recent advances in micro-GPS receivers permit their deployment on small mammals. One such technological advance, snapshot technology, allows for improved battery life by reducing the time to first fix via postponing recovery of satellite ephemeris (satellite location) data and processing of locations. However, no previous work has employed snapshot technology for small, terrestrial mammals. We evaluated performance of two types of micro-GPS (< 20 g) receivers (traditional and snapshot) on a small, semi-fossorial lagomorph, the pygmy rabbit (Brachylagus idahoensis), to understand how GPS errors might influence fine-scale assessments of space use and habitat selection. During stationary tests, microtopography (i.e., burrows) and satellite geometry had the largest influence on GPS fix success rate (FSR) and location error (LE). There was no difference between FSR while animals wore the GPS collars above ground (determined via light sensors) and FSR generated during stationary, above-ground trials, suggesting that animal behavior other than burrowing did not markedly influence micro-GPS errors. In our study, traditional micro-GPS receivers demonstrated similar FSR and LE to snapshot receivers, however, snapshot receivers operated inconsistently due to battery and software failures. In contrast, the initial traditional receivers deployed on animals experienced some breakages, but a modified collar design consistently functioned as expected. If such problems were resolved, snapshot technology could reduce the tradeoff between fix interval and battery life that occurs with traditional micro-GPS receivers. Our results suggest that micro-GPS receivers are capable of addressing questions about space use and resource selection by small mammals, but that additional techniques might be needed to identify use of habitat structures (e.g., burrows, tree cavities, rock crevices) that

  19. Evaluation of micro-GPS receivers for tracking small-bodied mammals.

    PubMed

    McMahon, Laura A; Rachlow, Janet L; Shipley, Lisa A; Forbey, Jennifer S; Johnson, Timothy R; Olsoy, Peter J

    2017-01-01

    GPS telemetry markedly enhances the temporal and spatial resolution of animal location data, and recent advances in micro-GPS receivers permit their deployment on small mammals. One such technological advance, snapshot technology, allows for improved battery life by reducing the time to first fix via postponing recovery of satellite ephemeris (satellite location) data and processing of locations. However, no previous work has employed snapshot technology for small, terrestrial mammals. We evaluated performance of two types of micro-GPS (< 20 g) receivers (traditional and snapshot) on a small, semi-fossorial lagomorph, the pygmy rabbit (Brachylagus idahoensis), to understand how GPS errors might influence fine-scale assessments of space use and habitat selection. During stationary tests, microtopography (i.e., burrows) and satellite geometry had the largest influence on GPS fix success rate (FSR) and location error (LE). There was no difference between FSR while animals wore the GPS collars above ground (determined via light sensors) and FSR generated during stationary, above-ground trials, suggesting that animal behavior other than burrowing did not markedly influence micro-GPS errors. In our study, traditional micro-GPS receivers demonstrated similar FSR and LE to snapshot receivers, however, snapshot receivers operated inconsistently due to battery and software failures. In contrast, the initial traditional receivers deployed on animals experienced some breakages, but a modified collar design consistently functioned as expected. If such problems were resolved, snapshot technology could reduce the tradeoff between fix interval and battery life that occurs with traditional micro-GPS receivers. Our results suggest that micro-GPS receivers are capable of addressing questions about space use and resource selection by small mammals, but that additional techniques might be needed to identify use of habitat structures (e.g., burrows, tree cavities, rock crevices) that

  20. Radio-tracking large wilderness mammals: integration of GPS and Argos technologies

    USGS Publications Warehouse

    Schwartz, Charles C.; Arthur, Steve M.

    1999-01-01

    We tested 30 prototype global positioning system (GPS) radiocollars on brown bears (Ursus arctos) over a 3-year period on the Kenai Peninsula, Alaska. Collars were of 2 design types: GPS units with an Argos (Argos Data collection and Location System) satellite uplink (n = 19) and GPS units where the data were stored on board (n = 10) for retrieval at a later date. All units also contained a conventional VHF (very high frequency) transmitter and weighed 1.7 kg. GPS-Argos units obtained 10-82% of expected GPS fixes, and fix rate declined significantly (P < 0.05) with time after deployment. Argos uplink success (proportion of successful transmissions of stored data) was linearly related to GPS fix rate (r = 0.91, P < 0.001). Storeon-board units obtained significantly more successful fixes when compared with the GPS-Argos units (t = -4.009, P < 0.001). Fix success rate for deployed store-on-board collars ranged from 13-96%; because of the increased number of attempted fixes per day, these collars obtained fixes on 97% of days deployed. Accuracy of the GPS units was less than predicted by the NAVSTAR GPS technology using the course acquisition code. Reduced accuracy was likely a result of the proportion of 2-dimensional versus 3-dimensional fixes obtained, although we could not determine this statistic from recorded data. Increased overstory closure was the only variable measured that partially explained the reduced likelihood of a successful fix. Stem density, stem diameter, and overstory height measured within 3 m of the collar did not affect fix success. GPS fix success rates for collars attached to bears varied more and were lower than fix rates for stationary collars placed in various vegetation types, suggesting that the bear, terrain, and movement all influence both fix and uplink success rate. Application of this new technology to grizzly and brown bear research and comparisons to studies with moose (Alces alces) are discussed.

  1. Validation of GPS atmospheric water vapor with WVR data in satellite tracking mode

    NASA Astrophysics Data System (ADS)

    Shangguan, M.; Heise, S.; Bender, M.; Dick, G.; Ramatschi, M.; Wickert, J.

    2015-01-01

    Slant-integrated water vapor (SIWV) data derived from GPS STDs (slant total delays), which provide the spatial information on tropospheric water vapor, have a high potential for assimilation to weather models or for nowcasting or reconstruction of the 3-D humidity field with tomographic techniques. Therefore, the accuracy of GPS STD is important, and independent observations are needed to estimate the quality of GPS STD. In 2012 the GFZ (German Research Centre for Geosciences) started to operate a microwave radiometer in the vicinity of the Potsdam GPS station. The water vapor content along the line of sight between a ground station and a GPS satellite can be derived from GPS data and directly measured by a water vapor radiometer (WVR) at the same time. In this study we present the validation results of SIWV observed by a ground-based GPS receiver and a WVR. The validation covers 184 days of data with dry and wet humidity conditions. SIWV data from GPS and WVR generally show good agreement with a mean bias of -0.4 kg m-2 and an rms (root mean square) of 3.15 kg m-2. The differences in SIWV show an elevation dependent on an rms of 7.13 kg m-2 below 15° but of 1.76 kg m-2 above 15°. Nevertheless, this elevation dependence is not observed regarding relative deviations. The relation between the differences and possible influencing factors (elevation angles, pressure, temperature and relative humidity) are analyzed in this study. Besides the elevation, dependencies between the atmospheric humidity conditions, temperature and the differences in SIWV are found.

  2. Head Tracking for Using a GPS-Aided 3D Audio MEMS IMU

    DTIC Science & Technology

    2006-02-01

    running on a PC-104 embedded placed on the side window of the test aircraft. , computer with a Linux operating system, which has proven Inertial...since the GPS antenna was removed, by the porting of the system to Linux /C++) which within one meter of the IMU (well within the GPS position...Reality. In from Dell Computer Corporation, Round Rock, Texas; laser Presence: Teleoperators and Virtual Enviroments , pp. 355- tracker from Faro

  3. Long term performance of radon mitigation systems

    SciTech Connect

    Prill, R.; Fisk, W.J.

    2002-03-01

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

  4. Long-term oxygen therapy.

    PubMed

    Christopher, Kent L; Porte, Phillip

    2011-02-01

    This article provides an overview of the status of long-term oxygen therapy (LTOT). In the United States, payment cutbacks are occurring as a result of congressionally mandated competitive bidding and capped rental programs. These Medicare programs are discussed. These legislative and regulatory changes may result in reduced patient access to appropriate oxygen-delivery systems that meet medical needs, including optimal ambulation. Prescribing LTOT is addressed in this article, as is the need for adequate patient education. The importance of appropriate monitoring and reassessment is presented. The use of an LTOT collaborative care model is discussed. Although the new intermittent flow oxygen-delivery systems have potential benefits, there is consensus that each patient should be tested on the specific device because of variability in delivery and patient response. Feasible locations for patient education and monitoring are identified.

  5. Asthma Medicines: Long-Term Control

    MedlinePlus

    ... Size Email Print Share Asthma Medicines: Long-term Control Page Content Article Body Corticosteroids Synthetic versions of ... form, they are used exclusively for long-term control; they are not very effective for acute symptoms. ...

  6. Consumer Direction in Long-Term Care.

    ERIC Educational Resources Information Center

    Generations, 2000

    2000-01-01

    Issue includes 17 theme articles on long-term care, covering legal issues, federal role, state programs, demonstration programs, family caregivers, home health care, home care workers, culturally appropriate long-term care, financial support, and cognitive impairments. (SK)

  7. Real-time ultrasound-guided PCNL using a novel SonixGPS needle tracking system.

    PubMed

    Li, Xiang; Long, Qingzhi; Chen, Xingfa; He, Dalin; Dalin, He; He, Hui

    2014-08-01

    SonixGPS is a successful ultrasound guidance position system. It helps to improve accuracy in performing complex puncture operations. This study firstly used SonixGPS to perform kidney calyx access in PCNL to investigate its effectiveness and safety. This was a prospectively randomized controlled study performed from September 2011 to October 2012. A total of 97 patients were prospectively randomized into two groups using random number generated from SAS software. 47 Patients were enrolled in conventional ultrasound-guided (US-guided) group and 50 patients were classified into SonixGPS-guided group. Nine patients were lost during follow-up. Hence, a total of 88 patients were qualified and analyzed. Preoperative examinations included urine analysis, urine culture, kidney function, coagulation profile and routine analysis of blood. Ultrasonography was used to evaluate the degree of hydronephrosis. The intraoperative findings, including blood loss, operating time, time to successful puncture, the number of attempts for successful puncture and hospital stay were recorded. The stone clearance rate and complications were analyzed. The present study showed no significant difference between the two groups in terms of demographic data, preoperative markers, stone clearance rate and the stone composition. However, the time to successful puncture, the number of trials for successful puncture, operating time and hospital length of stay were significantly decreased in the SonixGPS-guided group. Furthermore, the hemoglobin decrease was also obviously lower in the SonixGPS group than that in conventional US-guided group. SonixGPS needle tacking system guided PCNL is safe and effective in treating upper urinary tract stones. This novel technology makes puncturing more accuracy and can significantly decrease the incidence of relative hemorrhage and accelerate recovery.

  8. Open-loop GPS signal tracking at low elevation angles from a ground-based observation site

    NASA Astrophysics Data System (ADS)

    Beyerle, Georg; Zus, Florian

    2016-04-01

    For more than a decade space-based global navigation satellite system (GNSS) radio occultation (RO) observations are used by meteorological services world-wide for their numerical weather prediction models. In addition, climate studies increasingly rely on validated GNSS-RO data sets of atmospheric parameters. GNSS-RO profiles typically cover an altitude range from the boundary layer up to the upper stratosphere; their highest accuracy and precision, however, are attained at the tropopause level. In the lower troposphere, multipath ray propagation tend to induce signal amplitude and frequency fluctuations which lead to the development and implementation of open-loop signal tracking methods in GNSS-RO receiver firmwares. In open-loop mode the feed-back values for the carrier tracking loop are derived not from measured data, but from a Doppler frequency model which usually is extracted from an atmospheric climatology. In order to ensure that this receiver-internal parameter set, does not bias the carrier phase path observables, dual-channel open-loop GNSS-RO signal tracking was suggested. Following this proposal the ground-based "GLESER" (GPS low-elevation setting event recorder) campaign was established. Its objective was to disproof the existence of model-induced frequency biases using ground-based GPS observations at very low elevation angles. Between January and December 2014 about 2600 validated setting events, starting at geometric elevation angles of +2° and extending to -1°… - 1.5°, were recorded by the single frequency "OpenGPS" GPS receiver at a measurement site located close to Potsdam, Germany (52.3808°N, 13.0642°E). The study is based on the assumption that these ground-based observations may be used as proxies for space-based RO measurements, even if the latter occur on a one order of magnitude faster temporal scale. The "GLESER" data analysis shows that the open-loop Doppler model has negligible influence on the derived frequency profile

  9. Long Term Surface Salinity Measurements

    NASA Technical Reports Server (NTRS)

    Schmitt, Raymond W.; Brown, Neil L.

    2005-01-01

    Our long-term goal is to establish a reliable system for monitoring surface salinity around the global ocean. Salinity is a strong indicator of the freshwater cycle and has a great influence on upper ocean stratification. Global salinity measurements have potential to improve climate forecasts if an observation system can be developed. This project is developing a new internal field conductivity cell that can be protected from biological fouling for two years. Combined with a temperature sensor, this foul-proof cell can be deployed widely on surface drifters. A reliable in-situ network of surface salinity sensors will be an important adjunct to the salinity sensing satellite AQUARIUS to be deployed by NASA in 2009. A new internal-field conductivity cell has been developed by N Brown, along with new electronics. This sensor system has been combined with a temperature sensor to make a conductivity - temperature (UT) sensor suitable for deployment on drifters. The basic sensor concepts have been proven on a high resolution CTD. A simpler (lower cost) circuit has been built for this application. A protection mechanism for the conductivity cell that includes antifouling protection has also been designed and built. Mr. A.Walsh of our commercial partner E-Paint has designed and delivered time-release formulations of antifoulants for our application. Mr. G. Williams of partner Clearwater Instrumentation advised on power and communication issues and supplied surface drifters for testing.

  10. AB055. Long term NIV

    PubMed Central

    Siopi, Dimitra

    2016-01-01

    During the last decades, non-invasive mechanical ventilation has evolved into one of the most evidence-based areas of respiratory medicine, with many indications in acute or chronic respiratory failure. From the first application of negative pressure models during poliomyelitis epidemics to the new sophisticated positive pressure models, and the development of the “intelligent ventilators”, there has been a long time course. Undoubtedly the spur was given by better understanding of respiratory physiology during sleep and the shift of healthcare towards a chronic base. Novel randomized controlled trials (RCTs) established the use of NIV in acute respiratory failure due to exacerbations of COPD, as well as acute pulmonary edema and weaning from invasive mechanical ventilation. Long-term NIV has been used in neuromuscular diseases for many decades, first in Duchenne muscular dystrophy, and then spreading to other disorders of this category, increasing survival in inherited neuromuscular diseases. NIV should be initiated early in the course of the disease, when symptomatic nocturnal hypoventilation is detected. Combined with cough augmentation (physiotherapy, insufflation-exsufflation devices) and percutaneous gastrostomy feeding, it can delay tracheostomy and invasive ventilation. In ALS patients NIV improves the quality of life and increases survival, especially when there is no bulbar involvement. The right time to initiate ventilation in this group of patients is not well established since it is difficult to detect signs and symptom of respiratory impairment. Patients seem to benefit from an early application of NIV, and their personal decisions should always be considered before any intervention. In patients with chest wall disorders NIV—despite the fact that RCTs are lacking—has proved its value in many uncontrolled trials and numerous reports. It seems to improve the work of breathing, sleep architecture, nocturnal and daytime arterial blood gases. The

  11. Stapedectomy - long-term report.

    PubMed

    Shea, J J

    1982-01-01

    The long-term results with large fenestra stapedectomy with vein graft and Teflon piston are compared with results with the small fenestra stapedectomy with teflon piston directly into the vestibule. There were 1,943 operations in the former group and 2,155 in the latter when compared in 1970. One hundred consecutive patients from the beginning of each group with follow-up to present were compared. Results were generally the same with no great change in 15 and 20 years as compared to those at 5 years. The complication of perilymph fistula was caused by creating an opening in the footplate much larger than the prosthesis and was eliminated by interposing a living oval window seal if the opening was much larger than the prosthesis and a flap of lining membrane from the promontory when it was not. Other factors that influence a good result are discussed, including the type and the diameter of the piston used, the type of living oval window seal and the method of attachment to the incus. The small fenestra operation was found to be superior to the large, not only for the hearing gain achieved, but the case of performance and the freedom from complications due to migration of the prosthesis and/or the oval window seal. At present we have done about all that can be done for the conductive components. What remains is the sensorineural component which our studies indicate may be due to an autoimmune response.

  12. Long-term corrosion studies

    SciTech Connect

    Gdowski, G.

    1998-05-29

    The scope of this activity is to assess the long-term corrosion properties of metallic materials under consideration for fabricating waste package containers. Three classes of metals are to be assessed: corrosion resistant, intermediate corrosion resistant, and corrosion allowance. Corrosion properties to be evaluated are general, pitting and crevice corrosion, stress-corrosion cracking, and galvanic corrosion. The performance of these materials will be investigated under conditions that are considered relevant to the potential emplacement site. Testing in four aqueous solutions, and vapor phases above them, and at two temperatures are planned for this activity. (The environmental conditions, test metals, and matrix are described in detail in Section 3.0.) The purpose and objective of this activity is to obtain the kinetic and mechanistic information on degradation of metallic alloys currently being considered for waste package containers. This information will be used to provide assistance to (1) waste package design (metal barrier selection) (E-20-90 to E-20-92), (2) waste package performance assessment activities (SIP-PA-2), (3) model development (E-20-75 to E-20-89). and (4) repository license application.

  13. Long-Term Planning in Higher Education.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific and Cultural Organization, Bangkok (Thailand). Principal Regional Office for Asia and the Pacific.

    This report presents the concepts and issues discussed at a Regional Symposium on Long-term Planning in Higher Education held in Dhaka, Bangladesh, September 21-30, 1986. Chapter 1 explores some fundamental issues about the rationale for the objectives of long-term planning. It defines long-term planning in higher education, considers its…

  14. Long Term TOA - M Data and Information

    Atmospheric Science Data Center

    2015-06-30

    A Long-Term TOA and Constrained Surface Radiation Budget Project A Long-Term TOA and Constrained Surface Readiation Budget Dataset Using Merged CERES, ... and apply the knowledge to existing data to develop long-term (nearly 30 years) consistent and calibrated data product (TOA irradiances ...

  15. Private Long-Term Care Insurance: Value to Claimants and Implications for Long-Term Care Financing

    ERIC Educational Resources Information Center

    Doty, Pamela; Cohen, Marc A.; Miller, Jessica; Shi, Xiaomei

    2010-01-01

    Purpose: The purpose of this study was to obtain a profile of individuals with private long-term care (LTC) insurance as they begin using paid LTC services and track their patterns of service use, satisfaction with services and insurance, claims denial rates, and transitions over a 28-month period. Design and Methods: Ten LTC insurance companies…

  16. Private Long-Term Care Insurance: Value to Claimants and Implications for Long-Term Care Financing

    ERIC Educational Resources Information Center

    Doty, Pamela; Cohen, Marc A.; Miller, Jessica; Shi, Xiaomei

    2010-01-01

    Purpose: The purpose of this study was to obtain a profile of individuals with private long-term care (LTC) insurance as they begin using paid LTC services and track their patterns of service use, satisfaction with services and insurance, claims denial rates, and transitions over a 28-month period. Design and Methods: Ten LTC insurance companies…

  17. Complex Road Intersection Modelling Based on Low-Frequency GPS Track Data

    NASA Astrophysics Data System (ADS)

    Huang, J.; Deng, M.; Zhang, Y.; Liu, H.

    2017-09-01

    It is widely accepted that digital map becomes an indispensable guide for human daily traveling. Traditional road network maps are produced in the time-consuming and labour-intensive ways, such as digitizing printed maps and extraction from remote sensing images. At present, a large number of GPS trajectory data collected by floating vehicles makes it a reality to extract high-detailed and up-to-date road network information. Road intersections are often accident-prone areas and very critical to route planning and the connectivity of road networks is mainly determined by the topological geometry of road intersections. A few studies paid attention on detecting complex road intersections and mining the attached traffic information (e.g., connectivity, topology and turning restriction) from massive GPS traces. To the authors' knowledge, recent studies mainly used high frequency (1 s sampling rate) trajectory data to detect the crossroads regions or extract rough intersection models. It is still difficult to make use of low frequency (20-100 s) and easily available trajectory data to modelling complex road intersections geometrically and semantically. The paper thus attempts to construct precise models for complex road intersection by using low frequency GPS traces. We propose to firstly extract the complex road intersections by a LCSS-based (Longest Common Subsequence) trajectory clustering method, then delineate the geometry shapes of complex road intersections by a K-segment principle curve algorithm, and finally infer the traffic constraint rules inside the complex intersections.

  18. Black Petrels (Procellaria parkinsoni) Patrol the Ocean Shelf-Break: GPS Tracking of a Vulnerable Procellariiform Seabird

    PubMed Central

    Freeman, Robin; Dennis, Todd; Landers, Todd; Thompson, David; Bell, Elizabeth; Walker, Mike; Guilford, Tim

    2010-01-01

    Background Determining the foraging movements of pelagic seabirds is fundamental for their conservation. However, the vulnerability and elusive lifestyles of these animals have made them notoriously difficult to study. Recent developments in satellite telemetry have enabled tracking of smaller seabirds during foraging excursions. Methodology/Principal Findings Here, we report the first successful precision tracking of a c. 700 g seabird, the vulnerable Black Petrel, Procellaria parkinsoni, foraging at sea during the breeding season, using miniature GPS-logging technology. Employing a combination of high-resolution fixes and low-power duty-cycles, we present data from nine individual foraging excursions tracked during the chick-rearing period in February 2006. Conclusions/Significance We provide a snapshot of the species' foraging range and behaviour in relation to detailed underlying bathymetry off the coast of New Zealand, finding a significant relationship between foraging movements and regions of the shelf-break. We also highlight the potential of more sophisticated analyses to identify behavioural phenomena from position data alone. PMID:20174652

  19. The effect of feeding time on dispersal of Virola seeds by toucans determined from GPS tracking and accelerometers

    NASA Astrophysics Data System (ADS)

    Kays, Roland; Jansen, Patrick A.; Knecht, Elise M. H.; Vohwinkel, Reinhard; Wikelski, Martin

    2011-11-01

    Seed dispersal is critical to understanding forest dynamics but is hard to study because tracking seeds is difficult. Even for the best-studied dispersal system of the Neotropics, Virola nobilis, the dispersal kernel remains unknown. We combined high-resolution GPS/3D-acceleration bird tracking, seed-retention experiments, and field observations to quantify dispersal of V. nobilis by their principal dispersers, Ramphastos toucans. We inferred feeding events from movement data, and then estimated spatio-temporally explicit seed-dispersal kernels. Wild toucans moved an average of 1.8 km d -1 with two distinct activity peaks. Seed retention time in captive toucans averaged 25.5 min (range 4-98 min). Estimated seed dispersal distance averaged 144 ± 147 m, with a 56% likelihood of dispersal >100 m, two times further than the behaviour-naive estimate from the same data. Dispersal was furthest for seeds ingested in the morning, and increased with seed retention time, but only up to 60 min after feeding. Our study supports the long-standing hypothesis that toucans are excellent dispersers of Virola seeds. To maximize seed dispersal distances trees should ripen fruit in the morning when birds move the most, and produce fruits with gut-processing times around 60 min. Our study demonstrates how new tracking technology can yield nuanced seed dispersal kernels for animals that cannot be directly observed.

  20. Long-term solar-terrestrial observations

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The results of an 18-month study of the requirements for long-term monitoring and archiving of solar-terrestrial data is presented. The value of long-term solar-terrestrial observations is discussed together with parameters, associated measurements, and observational problem areas in each of the solar-terrestrial links (the sun, the interplanetary medium, the magnetosphere, and the thermosphere-ionosphere). Some recommendations are offered for coordinated planning for long-term solar-terrestrial observations.

  1. [Perspectives in long-term care insurance].

    PubMed

    Pick, P

    2007-03-01

    Twelve years after its introduction, long-term care insurance is back on the agenda and up for political reform. This paper shows why long-term care insurance needs to be reformed. The two central aspects on which reform projects focus are addressed: firstly, the structural improvement of nursing care and long-term care insurance and, secondly, the creation of a sustained financing. The principal conclusion is that, while there is a broad consensus about the structural improvement of long-term care insurance, opinions differ widely in the matter of its sustained financing. As a consequence, a coherent financing concept has yet to emerge.

  2. Tracking the movement of Hawaiian volcanoes; Global Positioning System (GPS) measurement

    USGS Publications Warehouse

    Dvorak, J.J.

    1992-01-01

    At some well-studied volcanoes, surface movements of at least several centimeters take place out to distances of about 10 km from the summit of the volcano. Widespread deformation of this type is relatively easy to monitor, because the necessary survey stations can be placed at favorable sites some distance from the summit of the volcano. Examples of deformation of this type include Kilauea and Mauna Loa in Hawaii, Krafla in Iceland, Long Valley in California, Camp Flegrei in Italy, and Sakurajima in Japan. In contrast, surface movement at some other volcanoes, usually volcanoes with steep slopes, is restricted to places within about 1 km of their summits. Examples of this class of volcanoes include Mount St. Helens in Washington, Etna in Italy, and Tangkuban Parahu in Indonesia. Local movement on remote, rugged volcanoes of this type is difficult to observe using conventional methods of measuring ground movement, which generally require a clear line-of-sight between points of interest. However, a revolutionary new technique, called the Global Positional System (GPS), provides a very efficient, alternative method of making such measurements. GPS, which uses satellites and ground-based receivers to accurately record slight crustal movements, is rapidly becoming the method of choice to measure deformation at volcanoes. 

  3. Virtual Models of Long-Term Care

    ERIC Educational Resources Information Center

    Phenice, Lillian A.; Griffore, Robert J.

    2012-01-01

    Nursing homes, assisted living facilities and home-care organizations, use web sites to describe their services to potential consumers. This virtual ethnographic study developed models representing how potential consumers may understand this information using data from web sites of 69 long-term-care providers. The content of long-term-care web…

  4. Virtual Models of Long-Term Care

    ERIC Educational Resources Information Center

    Phenice, Lillian A.; Griffore, Robert J.

    2012-01-01

    Nursing homes, assisted living facilities and home-care organizations, use web sites to describe their services to potential consumers. This virtual ethnographic study developed models representing how potential consumers may understand this information using data from web sites of 69 long-term-care providers. The content of long-term-care web…

  5. Long Term Preservation of Digital Information.

    ERIC Educational Resources Information Center

    Lorie, Raymond A.

    The preservation of digital data for the long term presents a variety of challenges from technical to social and organizational. The technical challenge is to ensure that the information, generated today, can survive long term changes in storage media, devices, and data formats. This paper presents a novel approach to the problem. It distinguishes…

  6. Long-Term Nutrition: A Clinician's Guide to Successful Long-Term Enteral Access in Adults.

    PubMed

    Bechtold, Matthew L; Mir, Fazia A; Boumitri, Christine; Palmer, Lena B; Evans, David C; Kiraly, Laszlo N; Nguyen, Douglas L

    2016-09-22

    Long-term nutrition support requires long-term enteral access. To ensure the success of long-term enteral access, many factors need to be taken into consideration. This article represents a guide to placing and maintaining access in patients requiring long-term nutrition and addresses many of the common questions regarding long-term enteral access, such as indications, types of access, feeding after access placed, and recognition and treatment of potential complications. This guide will help the clinician establish and maintain access to maximize nutrition in patients requiring long-term nutrition.

  7. High Efficiency GPS Block III L1 band Envelope Tracking Power Amplifier

    DTIC Science & Technology

    2016-03-31

    envelope sign igh efficiency lope tracking a -III L1-ba katani1, Jo entric Techno position resol block-III sa an current GP provide the specially in th...RF s abstract, the of an L-band power amplif e envelope tr used by radio . In Fig. 3 the and Bock-III 5 ar function, wh expansion. A ately 5 times... power amp pe tracking ar s with digi educes the iso iplexer greatly cking (ET) a f non-constan cking, the supp d by the lope of the RF throughout th s

  8. Paying for long-term care.

    PubMed Central

    Estes, C L; Bodenheimer, T

    1994-01-01

    Everyone agrees that insurance for long-term care is inadequate in the United States. Disagreement exists, however, on whether such insurance should be provided through the private or public sector. Private insurance generally uses the experience-rating principle that persons with higher risk of illness are charged higher premiums. For private insurance for long-term care, this principle creates a dilemma. Most policies will be purchased by the elderly; yet, because the elderly have a high risk of needing long-term care, only about 20% of them can afford the cost of premiums. A public-private partnership by which the government partially subsidizes private long-term-care insurance is unlikely to resolve this dilemma. Only a social insurance program for long-term care can provide universal, affordable, and equitable coverage. PMID:8128712

  9. IPPP GPS for tracking loading deformations induced by the storm Xynthia

    NASA Astrophysics Data System (ADS)

    Ferenc, Marcell; Nicolas, Joëlle; Durand, Frédéric; Li, Zhao; Boy, Jean-Paul; Perosanz, Félix; van Dam, Tonie

    2015-04-01

    Xynthia was a violent windstorm that progressed over Western Europe between the 27th of February and the 1st of March 2010. The huge low-pressure system (pressure drop of 40 mbar and storm surge of 1.5 m at La Rochelle tide gauge) crossed France from the southwest to the northeast over the course of about 20 hours. In this study, we first investigate the detailed spatial and temporal characteristics of the Xynthia storm. Then we analyse the effect of this storm on sub-daily 3D GPS (Global Positioning System) position time series computed with the iPPP (integer fixed ambiguity Precise Point Positioning) GINS-PC software method using the REPRO 2 products for about 100 stations of the French GNSS permanent network (RGP). We compare the GPS observations with the predicted time series derived from different geodynamical models for non-tidal atmospheric, oceanic and hydrological loading effects. These predicted time series are computed using different environmental data sets. For atmospheric pressure we used the ECMWF (the European Centre for Medium-Range Weather Forecasts) or MERRA (Modern-Era Retrospective Analysis for Research and Applications) pressure fields. Concerning the ocean's response we use different hypotheses such as inverse barometer (IB), non-IB or a dynamic ocean's response to winds and pressure forcing applying 2 Dimensions Gravity Waves model (MOG2D). We perform a spatial analysis to study the different behaviour of the coastal and inland sites. This study allows us to identify the ocean's dynamics on the continental shelf during the passage of this fast moving low pressure system. For comparison, these analyses are also performed for calm periods.

  10. Tracking Low Earth Orbit Small Debris with GPS Satellites as Bistatic Radar

    NASA Astrophysics Data System (ADS)

    Mahmud, M.; Qaisar, S.; Benson, C.

    2016-09-01

    Space debris is a growing problem and collisions are potentially lethal to satellites. Trajectories for small objects are predicted based on infrequent measurements, and the scale and therefore cost of maneuver required to avoid collisions is a function of trajectory accuracy. Frequent and precise observations will improve trajectory accuracy. In this paper, we extend on aspects of the feasibility of tracking space debris in Low Earth Orbit using emissions from GNSS satellites as bistatic radar illuminators. The wavelengths of GNSS signals are of order 20 cm and our primary focus is to track debris smaller than this, thereby maintaining phase stability of the scattered signals, enabling very long coherent processing intervals. However, the signals scattered by debris will be very weak at a terrestrial receiver, requiring the computationally expensive integration of a large number of signals, over an extended duration and with a large phased array. Detection of such weak signals in the presence of relatively strong direct-arrival signals requires extremely high cross-correlation protection. We show that sufficient cross-correlation protection can be obtained due to the large and varying Doppler shift, and also illustrate a novel processing approach utilizing downshifting of the collected signal to audio frequency. This technique dramatically reduces the cost and complexity of updating debris trajectories. The processing cost of preserving an uncertainty volume of many hundreds of meters around the predicted debris track is very modest, and searching within that uncertainty volume is undertaken at audio sampling rates. Moreover, we explore techniques that further lower the already modest cost of the non-linear search within the preserved uncertainty volume. We conclude with an outline of a system using these techniques that could provide centimetre level tracking of large quantities of small orbital objects at a modest cost.

  11. Hospital diversification into long-term care.

    PubMed

    Shah, A; Fennell, M; Mor, V

    2001-01-01

    In the 1990s, acute care hospitals in the United States encountered an unstable operating environment created by a series of transformations in the health care delivery system and long-term-care market. Confronted with an array of economic pressures and demographic changes, hospitals were motivated to engage in long-term-care diversification, such as establishing a long-term-care unit or providing home health services, as a means of entering new markets and ensuring financial stability. This article examines the organizational, market, and community factors associated with this strategic activity among a national sample of urban and rural hospitals.

  12. Habitat use of bats in relation to wind turbines revealed by GPS tracking

    NASA Astrophysics Data System (ADS)

    Roeleke, Manuel; Blohm, Torsten; Kramer-Schadt, Stephanie; Yovel, Yossi; Voigt, Christian C.

    2016-07-01

    Worldwide, many countries aim at countering global climate change by promoting renewable energy. Yet, recent studies highlight that so-called green energy, such as wind energy, may come at environmental costs, for example when wind turbines kill birds and bats. Using miniaturized GPS loggers, we studied how an open-space foraging bat with high collision risk with wind turbines, the common noctule Nyctalus noctula (Schreber, 1774), interacts with wind turbines. We compared actual flight trajectories to correlated random walks to identify habitat variables explaining the movements of bats. Both sexes preferred wetlands but used conventionally managed cropland less than expected based on availability. During midsummer, females traversed the land on relatively long flight paths and repeatedly came close to wind turbines. Their flight heights above ground suggested a high risk of colliding with wind turbines. In contrast, males recorded in early summer commuted straight between roosts and foraging areas and overall flew lower than the operating range of most turbine blades, suggesting a lower collision risk. Flight heights of bats suggest that during summer the risk of collision with wind turbines was high for most studied bats at the majority of currently installed wind turbines. For siting of wind parks, preferred bat habitats and commuting routes should be identified and avoided.

  13. Aging in Activity Space: Results From Smartphone-Based GPS-Tracking of Urban Seniors.

    PubMed

    York Cornwell, Erin; Cagney, Kathleen A

    2017-09-01

    Prior research emphasizes the importance of the residential neighborhood context during later life but little attention has been afforded to other areas that older adults encounter as they move beyond their residential environments for daily activities and social interactions. This study examines the predominance of the residential context within older adults' everyday lives. We provided 60 older adults in four New York City neighborhoods with iPhones, which captured Global Positioning Systems (GPS) locations at 5-min intervals over 1 week (n = 55,561) and 17 ecological momentary assessments (EMAs) over 4 days (n = 757) to assess real-time activities. Older adults in our sample spent nearly 40% of their time outside of their residential tracts and they visited 28 other tracts, on average. Exercising, shopping, socializing, and social activities were especially likely to take place outside of residential tracts. Differences in residential and nonresidential poverty exposure vary across gender, race/ethnicity, education, car ownership, and residential areas. Measuring activity space, rather than relying on residential tracts, allows examination of the social environments that are relevant for older adults' everyday lives. Variation in characteristics of activity spaces may be an underexplored source of differences in health and well-being during later life.

  14. Habitat use of bats in relation to wind turbines revealed by GPS tracking

    PubMed Central

    Roeleke, Manuel; Blohm, Torsten; Kramer-Schadt, Stephanie; Yovel, Yossi; Voigt, Christian C.

    2016-01-01

    Worldwide, many countries aim at countering global climate change by promoting renewable energy. Yet, recent studies highlight that so-called green energy, such as wind energy, may come at environmental costs, for example when wind turbines kill birds and bats. Using miniaturized GPS loggers, we studied how an open-space foraging bat with high collision risk with wind turbines, the common noctule Nyctalus noctula (Schreber, 1774), interacts with wind turbines. We compared actual flight trajectories to correlated random walks to identify habitat variables explaining the movements of bats. Both sexes preferred wetlands but used conventionally managed cropland less than expected based on availability. During midsummer, females traversed the land on relatively long flight paths and repeatedly came close to wind turbines. Their flight heights above ground suggested a high risk of colliding with wind turbines. In contrast, males recorded in early summer commuted straight between roosts and foraging areas and overall flew lower than the operating range of most turbine blades, suggesting a lower collision risk. Flight heights of bats suggest that during summer the risk of collision with wind turbines was high for most studied bats at the majority of currently installed wind turbines. For siting of wind parks, preferred bat habitats and commuting routes should be identified and avoided. PMID:27373219

  15. Habitat use of bats in relation to wind turbines revealed by GPS tracking.

    PubMed

    Roeleke, Manuel; Blohm, Torsten; Kramer-Schadt, Stephanie; Yovel, Yossi; Voigt, Christian C

    2016-07-04

    Worldwide, many countries aim at countering global climate change by promoting renewable energy. Yet, recent studies highlight that so-called green energy, such as wind energy, may come at environmental costs, for example when wind turbines kill birds and bats. Using miniaturized GPS loggers, we studied how an open-space foraging bat with high collision risk with wind turbines, the common noctule Nyctalus noctula (Schreber, 1774), interacts with wind turbines. We compared actual flight trajectories to correlated random walks to identify habitat variables explaining the movements of bats. Both sexes preferred wetlands but used conventionally managed cropland less than expected based on availability. During midsummer, females traversed the land on relatively long flight paths and repeatedly came close to wind turbines. Their flight heights above ground suggested a high risk of colliding with wind turbines. In contrast, males recorded in early summer commuted straight between roosts and foraging areas and overall flew lower than the operating range of most turbine blades, suggesting a lower collision risk. Flight heights of bats suggest that during summer the risk of collision with wind turbines was high for most studied bats at the majority of currently installed wind turbines. For siting of wind parks, preferred bat habitats and commuting routes should be identified and avoided.

  16. Comparison of a novel real-time SonixGPS needle-tracking ultrasound technique with traditional ultrasound for vascular access in a phantom gel model.

    PubMed

    Kopac, Daniel S; Chen, Jerry; Tang, Raymond; Sawka, Andrew; Vaghadia, Himat

    2013-09-01

    . Use of the novel SonixGPS needle-tracking ultrasound system (UltraSonix, Richmond, BC, Canada) was not associated with a higher success rate of vascular puncture compared with the traditional ultrasound-guided technique. Assessment of mental task load significantly favored the use of the ultrasound GPS over the traditional ultrasound technique. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  17. Long Term Effects of Food Poisoning

    MedlinePlus

    ... develop chronic arthritis. Brain and nerve damage A Listeria infection can lead to meningitis, an inflammation of ... brain. If a newborn infant is infected with Listeria , long-term consequences may include mental retardation, seizures, ...

  18. Mental Health in Long Term Care Settings.

    ERIC Educational Resources Information Center

    Shore, Herbert

    1978-01-01

    There are many ways in which long-term care facilities attempt to cope with the mental health problems of the elderly. The author reviews five factors crucial to effective care for the aged in these facilities. (Author/RK)

  19. Roadmap to Long-Term Monitoring Optimization

    EPA Pesticide Factsheets

    This roadmap focuses on optimization of established long-term monitoring programs for groundwater. Tools and techniques discussed concentrate on methods for optimizing the monitoring frequency and spatial (three-dimensional) distribution of wells ...

  20. Long-term-care legal update.

    PubMed

    Fiesta, J

    1998-04-01

    As more nurses move from the acute care setting to long-term-care and home health care, different practice issues arise. To maximize liability protection, nurses must understand the legal issues unique to each delivery system.

  1. Evidence-based long term care design.

    PubMed

    Calkins, Margaret P

    2009-01-01

    Research on the impact of the built environment in long-term care settings continues to grow. This article focuses on work conducted and published since 2000, when an earlier review on research on dementia and design was published. The vast majority of research that addressed neurological conditions in residents in long-term care settings (assisted living and nursing homes) relates to Alzheimer's disease and related dementias.

  2. Tracking Mallards (Anas platyrhynchos) with GPS Satellite Transmitters Along Their Migration Route Through Northeast Asia.

    PubMed

    Shin, Jeong-Hwa; Lee, Ki-Sup; Kim, Seol-Hee; Hwang, Jong-Kyung; Woo, Chanjin; Kim, Jiyeon; Kim, Jung-Hyun; Suh, Jae-Hwa; Jeong, Jipseol; Wang, Seung-Jun; Chung, Hyen-Mi; Yu, Seung-do; Choi, Kyung-Hee; Mo, In-Pil

    2016-05-01

    In this study, Global Positioning System satellite transmitters were attached to three mallards (Anas platyrhynchos) wintering in South Korea to track their migration routes, stopover sites, breeding sites, and migration patterns. We successfully tracked only one mallard (no. 108917) from November 15, 2011, to November 29, 2013, and determined separate migration routes in two cases of spring migration and one case of fall migration. The mallard repeatedly migrated to the same final destination, even though the travel path varied. We identified six stopover sites: Hunhe River, Liaohe River, Yinma River, Yalu River, Songjeon Bay, and Dahuofang Reservoir in China and South Korea. The wintering sites of two migration cases were discovered to be identical (Gokgyo River in Asan, South Korea). The terminal sites, which were presumed to be breeding grounds, were the same in both cases (Hinggan League in Inner Mongolia Autonomous Region, China). On the basis of the migration routes identified in this study, we suggest that future efforts to control highly pathogenic avian influenza (HPAI) should not only include avian influenza surveillance but also implement flyway-based strategies, with regard to all countries affected by potential HPAI outbreaks.

  3. Long Term Outcomes after Pediatric Liver Transplantation

    PubMed Central

    2013-01-01

    Long term outcomes after liver transplantation are major determinants of quality of life and of the value of this heroic treatment. As short term outcomes are excellent, our community is turning to take a harder look at long term outcomes. The purpose of this paper is to review these outcomes, and highlight proposed treatments, as well as pressing topics needing to be studied. A systemic review of the English literature was carried in PubMed, covering all papers addressing long term outcomes in pediatric liver transplant from 2000-2013. Late outcomes after pediatric liver transplant affect the liver graft in the form of chronic liver dysfunction. The causes include rejection particularly humoral rejection, but also de novo autoimmune hepatitis, and recurrent disease. The metabolic syndrome is a major factor in long term cardiovascular complication risk. Secondary infections, kidney dysfunction and malignancy remain a reality of those patients. There is growing evidence of late cognitive and executive function delays affecting daily life productivity as well as likely adherence. Finally, despite a good health status, quality of life measures are comparable to those of children with chronic diseases. Long term outcomes are the new frontier in pediatric liver transplantation. Much is needed to improve graft survival, but also to avoid systemic morbidities from long term immunosuppression. Quality of life is a new inclusive measure that will require interventions and innovative approaches respectful not only on the patients but also of their social circle. PMID:24511516

  4. GPS Tracking of Free-Ranging Pigs to Evaluate Ring Strategies for the Control of Cysticercosis/Taeniasis in Peru.

    PubMed

    Pray, Ian W; Swanson, Dallas J; Ayvar, Viterbo; Muro, Claudio; Moyano, Luz M; Gonzalez, Armando E; Garcia, Hector H; O'Neal, Seth E

    2016-04-01

    Taenia solium, a parasitic cestode that affects humans and pigs, is the leading cause of preventable epilepsy in the developing world. T. solium eggs are released into the environment through the stool of humans infected with an adult intestinal tapeworm (a condition called taeniasis), and cause cysticercosis when ingested by pigs or other humans. A control strategy to intervene within high-risk foci in endemic communities has been proposed as an alternative to mass antihelminthic treatment. In this ring strategy, antihelminthic treatment is targeted to humans and pigs residing within a 100 meter radius of a pig heavily-infected with cysticercosis. Our aim was to describe the roaming ranges of pigs in this region, and to evaluate whether the 100 meter radius rings encompass areas where risk factors for T. solium transmission, such as open human defecation and dense pig activity, are concentrated. In this study, we used Global Positioning System (GPS) devices to track pig roaming ranges in two rural villages of northern Peru. We selected 41 pigs from two villages to participate in a 48-hour tracking period. Additionally, we surveyed all households to record the locations of open human defecation areas. We found that pigs spent a median of 82.8% (IQR: 73.5, 94.4) of their time roaming within 100 meters of their homes. The size of home ranges varied significantly by pig age, and 93% of the total time spent interacting with open human defecation areas occurred within 100 meters of pig residences. These results indicate that 100 meter radius rings around heavily-infected pigs adequately capture the average pig's roaming area (i.e., home range) and represent an area where the great majority of exposure to human feces occurs.

  5. GPS Tracking of Free-Ranging Pigs to Evaluate Ring Strategies for the Control of Cysticercosis/Taeniasis in Peru

    PubMed Central

    Pray, Ian W.; Swanson, Dallas J.; Ayvar, Viterbo; Muro, Claudio; Moyano, Luz M.; Gonzalez, Armando E.; Garcia, Hector H.; O’Neal, Seth E.

    2016-01-01

    Background Taenia solium, a parasitic cestode that affects humans and pigs, is the leading cause of preventable epilepsy in the developing world. T. solium eggs are released into the environment through the stool of humans infected with an adult intestinal tapeworm (a condition called taeniasis), and cause cysticercosis when ingested by pigs or other humans. A control strategy to intervene within high-risk foci in endemic communities has been proposed as an alternative to mass antihelminthic treatment. In this ring strategy, antihelminthic treatment is targeted to humans and pigs residing within a 100 meter radius of a pig heavily-infected with cysticercosis. Our aim was to describe the roaming ranges of pigs in this region, and to evaluate whether the 100 meter radius rings encompass areas where risk factors for T. solium transmission, such as open human defecation and dense pig activity, are concentrated. Methodology/Principal Findings In this study, we used Global Positioning System (GPS) devices to track pig roaming ranges in two rural villages of northern Peru. We selected 41 pigs from two villages to participate in a 48-hour tracking period. Additionally, we surveyed all households to record the locations of open human defecation areas. We found that pigs spent a median of 82.8% (IQR: 73.5, 94.4) of their time roaming within 100 meters of their homes. The size of home ranges varied significantly by pig age, and 93% of the total time spent interacting with open human defecation areas occurred within 100 meters of pig residences. Conclusions/Significance These results indicate that 100 meter radius rings around heavily-infected pigs adequately capture the average pig’s roaming area (i.e., home range) and represent an area where the great majority of exposure to human feces occurs. PMID:27035825

  6. Mobility and Active Ageing in Suburban Environments: Findings from In-Depth Interviews and Person-Based GPS Tracking.

    PubMed

    Zeitler, Elisabeth; Buys, Laurie; Aird, Rosemary; Miller, Evonne

    2012-01-01

    Background. Governments face a significant challenge to ensure that community environments meet the mobility needs of an ageing population. Therefore, it is critical to investigate the effect of suburban environments on the choice of transportation and its relation to participation and active ageing. Objective. This research explores if and how suburban environments impact older people's mobility and their use of different modes of transport. Methods. Data derived from GPS tracking, travel diaries, brief questionnaires, and semistructured interviews were gathered from thirteen people aged from 56 to 87 years, living in low-density suburban environments in Brisbane, Australia. Results. The suburban environment influenced the choice of transportation and out-of-home mobility. Both walkability and public transportation (access and usability) impact older people's transportation choices. Impracticality of active and public transportation within suburban environments creates car dependency in older age. Conclusion. Suburban environments often create barriers to mobility, which impedes older people's engagement in their wider community and ability to actively age in place. Further research is needed to develop approaches towards age-friendly suburban environments which will encourage older people to remain active and engaged in older age.

  7. Long-term prescribing of antidepressants in the older population: a qualitative study

    PubMed Central

    Dickinson, Rebecca; Knapp, Peter; House, Allan O; Dimri, Vandana; Zermansky, Arnold; Petty, Duncan; Holmes, John; Raynor, David K

    2010-01-01

    Background High rates of long-term antidepressant prescribing have been identified in the older population. Aims To explore the attitudes of older patients and their GPs to taking long-term antidepressant therapy, and their accounts of the influences on long-term antidepressant use. Design of study Qualitative study using in-depth semi-structured interviews. Setting One primary care trust in North Bradford. Method Thirty-six patients aged ≥75 years and 10 GPs were interviewed. Patients were sampled to ensure diversity in age, sex, antidepressant type, and home circumstances. Results Participants perceived significant benefits and expressed little apprehension about taking long-term antidepressants, despite being aware of the psychological and social factors involved in onset and persistence of depression. Barriers to discontinuation were identified following four themes: pessimism about the course and curability of depression; negative expectations and experiences of ageing; medicine discontinuation perceived by patients as a threat to stability; and passive (therapeutic momentum) and active (therapeutic maintenance) decisions to accept the continuing need for medication. Conclusion There is concern at a public health level about high rates of long-term antidepressant prescribing, but no evidence was found of a drive for change either from the patients or the doctors interviewed. Any apprehension was more than balanced by attitudes and behaviours supporting continuation. These findings will need to be incorporated into the planning of interventions aimed at reducing long-term antidepressant prescribing in older people. PMID:20353660

  8. Long-Term Space Weather Forecasting: Parameters and Accuracy Needed for the Ionosphere/Thermosphere

    NASA Astrophysics Data System (ADS)

    Schunk, R. W.; Scherliess, L.; Sojka, J. J.; Thompson, D. C.; Zhu, L.

    2010-12-01

    Many of the problems associated with space weather pertain to the ionosphere-thermosphere system. Space weather can affect over-the-horizon (OTH) radars, HF communications, surveying and navigation systems, surveillance, spacecraft charging, orbital calculations, power grids, pipelines, and the FAA’s Wide-Area Augmentation System (WAAS). As shown by the meteorologists and oceanographers, the best weather models are physics-based data assimilation models. As the physics-based models improve and more data are included in the assimilation scheme, the data assimilation models have been shown to provide more reliable specifications and forecasts. Therefore, in an effort to mitigate the adverse effects of space weather, we developed and are continuing to develop four data assimilation models, including two for the ionosphere (GAIM-GM and GAIM-FP), one for the high-latitude ionosphere dynamics and electrodynamics (IDED), and one for the thermosphere. The ionosphere models assimilate bottom-side Ne profiles from 100 ionosondes, slant TEC from 1000 ground GPS/TEC stations, in situ Ne from 4 DMSP satellites, occultation data from multiple satellites, and line-of-sight UV emissions measured by satellites. The IDED model assimilates cross-track ion velocities from the 4 DMSP satellites, line-of-sight ion velocities from the SuperDarn radar system, and magnetic perturbations from 100 ground magnetometers and from the Iridium constellation of satellites. These data assimilation models provide reliable specifications and short-term forecasts. However, for long-term forecasts it is useful to have a chain of coupled physics-based models from the Sun’s surface to the ionosphere-thermosphere system. Some of the issues that we will address with regard to long-term forecasting include the role a data assimilation model plays in providing a reliable specification, the resolution needed to describe important space weather features, the parameters needed for applications, and the

  9. Long-term symptom relief after septoplasty.

    PubMed

    Sundh, Carolina; Sunnergren, Ola

    2015-10-01

    The results for long-term symptom relief after septoplasty are contradictory in reviewed publications but the findings suggest that results are unsatisfactory. In this study, we analyzed and compared short- and long-term symptom relief after septoplasty and factors possibly associated with symptom relief. 111 patients that underwent septoplasty between 2008 and 2010 were included in the study. Medical charts were reviewed for preoperative characteristics and assessments. Data on short-term symptom relief (6 months) were retrieved from the Swedish National Quality Registry for Septoplasty; data on long-term symptom relief (34-70 months) were collected through a questionnaire. Upon the 34-70 month follow-up, 53% of the patients reported that symptoms either remained or had worsened and 83% reported nasal obstruction. Degree of symptom relief was significantly higher among patients not reporting nasal obstruction than among patients reporting nasal obstruction at long-term follow-up. The proportion of patients that reported "my symptoms are gone" declined from 53% after 6 months to 18% after 34-70 months. None of the factors taken into consideration, age at surgery, gender, follow-up time, primary operation/reoperation, history of nasal trauma, self-reported allergy, rhinometric obstruction, or same sided rhinometric, clinical and subjective nasal obstruction were associated with symptom relief. The long-term results after septoplasty are unsatisfactory. A majority of patients report that their symptoms remain after septoplasty.

  10. Long-term outcomes of autoimmune pancreatitis

    PubMed Central

    Ikeura, Tsukasa; Miyoshi, Hideaki; Shimatani, Masaaki; Uchida, Kazushige; Takaoka, Makoto; Okazaki, Kazuichi

    2016-01-01

    Autoimmune pancreatitis (AIP) has been considered a favorable-prognosis disease; however, currently, there is limited information on natural course of AIP during long-term follow-up. Recently published studies regarding the long-term outcomes of AIP has demonstrated the developments of pancreatic stone formation, exocrine insufficiency, and endocrine insufficiency are observed in 5%-41%, 34%-82%, and 38%-57% of patients having the disease. Furthermore, the incidence rate of developing pancreatic cancer ranges from 0% to 4.8% during the long-term follow-up. The event of death from AIP-related complications other than accompanying cancer is likely to be rare. During follow-up of AIP patients, careful surveillance for not only relapse of the disease but also development of complications at regular intervals is needed. PMID:27678359

  11. Valuing a long-term care facility.

    PubMed

    Mellen, C M

    1992-10-01

    The business valuation industry generally uses at least one of three basic approaches to value a long-term care facility: the cost approach, sales comparison approach, or income approach. The approach that is chosen and the resulting weight that is applied to it depend largely on the circumstances involved. Because a long-term care facility is a business enterprise, more weight usually is given to the income approach which factors into the estimate of value both the tangible and intangible assets of the facility.

  12. Keratoprosthesis: a long-term review.

    PubMed Central

    Barnham, J. J.; Roper-Hall, M. J.

    1983-01-01

    A keratoprosthesis (KP), is an artificial cornea which is inserted into an opacified cornea in an attempt to restore useful vision or, less commonly, to make the eye comfortable in painful keratopathy. Results o a retrospective study of 35 patients, with 55 KP insertions, are reviewed with regard to visual acuity, length of time vision is maintained, retention time, and complication. Overall there were a number of long-term real successes, eith retention of the KP and maintenance of improved vision in eyes not amenable to conventional treatment. Careful long-term follow-up was needed, with further surgical procedures often being necessary. Images PMID:6860613

  13. Long-term Outcomes after Severe Shock

    PubMed Central

    Pratt, Cristina M.; Hirshberg, Eliotte L.; Jones, Jason P.; Kuttler, Kathryn G.; Lanspa, Michael J.; Wilson, Emily L.; Hopkins, Ramona O.; Brown, Samuel M.

    2014-01-01

    Background Severe shock is a life-threatening condition with very high short-term mortality. Whether the long-term outcomes among survivors of severe shock are similar to long-term outcomes of other critical illness survivors is unknown. We therefore sought to assess long-term survival and functional outcomes among 90-day survivors of severe shock and determine whether clinical predictors were associated with outcomes. Methods Seventy-six patients who were alive 90 days after severe shock (received ≥1 mcg/kg/min of norepinephrine equivalent) were eligible for the study. We measured three-year survival and long-term functional outcomes using the Medical Outcomes Study 36-Item Short-Form Health Survey, the EuroQOL 5-D-3L, the Hospital Anxiety and Depression Scale, the Impact of Event Scale-Revised and an employment instrument. We also assessed the relationship between in-hospital predictors and long-term outcomes. Results The mean long-term survival was 5.1 years: 82% (62/76) of patients survived, of whom 49 were eligible for follow-up. Patients who died were older than patients who survived. Thirty-six patients completed a telephone interview a mean of five years after hospital admission. The patients’ Physical Functioning scores were below US population norms (p<0.001), whereas mental health scores were similar to population norms. Nineteen percent of the patients had symptoms of depression, 39% had symptoms of anxiety and 8% had symptoms of posttraumatic stress disorder. Thirty-six percent were disabled, and 17% were working full time. Conclusions Early survivors of severe shock had a high three-year survival rate. Patients’ long term physical and psychological outcomes were similar to those reported for cohorts of less severely ill ICU survivors. Anxiety and depression were relatively common, but only a few patients had symptoms of posttraumatic stress disorder. This study supports the observation that acute illness severity does not determine long-term

  14. [Fetal pain: immediate and long term consequences].

    PubMed

    Houfflin Debarge, Véronique; Dutriez, Isabelle; Pusniak, Benoit; Delarue, Eléonore; Storme, Laurent

    2010-06-01

    Several situations are potentially painful for fetuses, such as malformations and invasive procedures. Nociceptive pathways are known to be functional at 26 weeks. Even if it is not possible to evaluate the fetal experience of pain, it is essential to examine its immediate and long-term consequences. As early as the beginning of the second trimester, hemodynamic and hormonal responses are observed following fetal nociceptive stimulation, In experimental studies, long-term changes have been noted in the corticotrop axis, subsequent responses to pain, and behavior after perinatal nociceptive stimulation.

  15. Long-term outcomes after severe shock.

    PubMed

    Pratt, Cristina M; Hirshberg, Eliotte L; Jones, Jason P; Kuttler, Kathryn G; Lanspa, Michael J; Wilson, Emily L; Hopkins, Ramona O; Brown, Samuel M

    2015-02-01

    Severe shock is a life-threatening condition with very high short-term mortality. Whether the long-term outcomes among survivors of severe shock are similar to long-term outcomes of other critical illness survivors is unknown. We therefore sought to assess long-term survival and functional outcomes among 90-day survivors of severe shock and determine whether clinical predictors were associated with outcomes. Seventy-six patients who were alive 90 days after severe shock (received ≥1 μg/kg per minute of norepinephrine equivalent) were eligible for the study. We measured 3-year survival and long-term functional outcomes using the Medical Outcomes Study 36-Item Short-Form Health Survey, the EuroQOL 5-D-3L, the Hospital Anxiety and Depression Scale, the Impact of Event Scale-Revised, and an employment instrument. We also assessed the relationship between in-hospital predictors and long-term outcomes. The mean long-term survival was 5.1 years; 82% (62 of 76) of patients survived, of whom 49 were eligible for follow-up. Patients who died were older than patients who survived. Thirty-six patients completed a telephone interview a mean of 5 years after hospital admission. The patients' Physical Functioning scores were below U.S. population norms (P < 0.001), whereas mental health scores were similar to population norms. Nineteen percent of the patients had symptoms of depression, 39% had symptoms of anxiety, and 8% had symptoms of posttraumatic stress disorder. Thirty-six percent were disabled, and 17% were working full-time. Early survivors of severe shock had a high 3-year survival rate. Patients' long-term physical and psychological outcomes were similar to those reported for cohorts of less severely ill intensive care unit survivors. Anxiety and depression were relatively common, but only a few patients had symptoms of posttraumatic stress disorder. This study supports the observation that acute illness severity does not determine long-term outcomes. Even extremely

  16. Applying activity-based costing in long-term care.

    PubMed

    Wodchis, W P

    1998-01-01

    As greater numbers of the elderly use health services, and as health care costs climb, effective financial tracking is essential. Cost management in health care can benefit if costs are linked to the care activities where they are incurred. Activity-based costing (ABC) provides a useful approach. The framework aligns costs (inputs), through activities (process), to outputs and outcomes. It allocates costs based on client care needs rather than management structure. The ABC framework was tested in a residential care facility and in supportive housing apartments. The results demonstrate the feasibility and advantages of ABC for long term care agencies, including community-based care.

  17. Investigating long-term subsidence at Medicine Lake Volcano, CA, using multitemporal InSAR

    NASA Astrophysics Data System (ADS)

    Parker, Amy L.; Biggs, Juliet; Lu, Zhong

    2014-11-01

    Long-term volcanic subsidence provides insight into intereruptive processes, which comprise the longest portion of the eruptive cycle. Ground-based geodetic surveys of Medicine Lake Volcano (MLV), northern CA, document subsidence at rates of ˜-10 mm yr-1 between 1954 and 2004. The long observation period plus the duration and stable magnitude of this signal presents an ideal opportunity to study long-term volcanic deformation, but this first requires accurate knowledge of the geometry and magnitude of the source. Best-fitting analytical source models to past levelling and GPS data sets show conflicting source parameters-primarily the model depth. To overcome this, we combine multiple tracks of InSAR data, each with a different look angle, to improve upon the spatial resolution of ground-based measurements. We compare the results from InSAR to those of past geodetic studies, extending the geodetic record to 2011 and demonstrating that subsidence at MLV continues at ˜-10 mm yr-1. Using geophysical inversions, we obtain the best-fitting analytical source model-a sill located at 9-10 km depth beneath the caldera. This model geometry is similar to those of past studies, providing a good fit to the high spatial density of InSAR measurements, while accounting for the high ratio of vertical to horizontal deformation derived from InSAR and recorded by existing levelling and GPS data sets. We discuss possible causes of subsidence and show that this model supports the hypothesis that deformation at MLV is driven by tectonic extension, gravitational loading, plus a component of volume loss at depth, most likely due to cooling and crystallization within the intrusive complex that underlies the edifice. Past InSAR surveys at MLV, and throughout the Cascades, are of variable success due to dense vegetation, snow cover and atmospheric artefacts. In this study, we demonstrate how InSAR may be successfully used in this setting by applying a suite of multitemporal analysis methods

  18. Long-Term Memory and Learning

    ERIC Educational Resources Information Center

    Crossland, John

    2011-01-01

    The English National Curriculum Programmes of Study emphasise the importance of knowledge, understanding and skills, and teachers are well versed in structuring learning in those terms. Research outcomes into how long-term memory is stored and retrieved provide support for structuring learning in this way. Four further messages are added to the…

  19. Long-Term Memory and Learning

    ERIC Educational Resources Information Center

    Crossland, John

    2011-01-01

    The English National Curriculum Programmes of Study emphasise the importance of knowledge, understanding and skills, and teachers are well versed in structuring learning in those terms. Research outcomes into how long-term memory is stored and retrieved provide support for structuring learning in this way. Four further messages are added to the…

  20. Professionalism in Long-Term Care Settings

    ERIC Educational Resources Information Center

    Lubinski, Rosemary

    2006-01-01

    Speech-language pathologists who serve elders in a variety of long-term care settings have a variety of professional skills and responsibilities. Fundamental to quality service is knowledge of aging and communication changes and disorders associated with this process, institutional alternatives, and the changing nature of today's elders in…

  1. Long-Term Impacts of Educational Interventions

    ERIC Educational Resources Information Center

    Deming, David James

    2010-01-01

    The school accountability movement has led to a marked increase in the use of standardized test scores to measure school and teacher productivity, yet little is known about the correlation between test score gains and improvements in long-term outcomes. In the first chapter of my dissertation, I study the impact of a school choice policy in…

  2. Long-term studies of dopamine agonists.

    PubMed

    Hubble, Jean P

    2002-02-26

    Dopamine agonists have long been used as adjunctive therapy for the treatment of Parkinson's disease (PD). In more recent years these drugs have also been proved safe and effective as initial therapy in lieu of levodopa in the treatment of PD. Long-term levodopa therapy is associated with motor complications, including fluctuating response patterns and dyskinesia. By initially introducing a dopamine agonist as symptomatic drug therapy, it may be possible to postpone the use of levodopa and delay or prevent the development of motor complications. Recently, four clinical trials have explored this hypothesis by comparing the long-term response and side effects of levodopa with dopamine agonist therapy. The drugs studied have included ropinirole, pramipexole, cabergoline, and pergolide. In each of these projects, the occurrence of motor complications, such as wearing off and dyskinesia, was significantly less in the subjects assigned to initiation of therapy with a dopamine agonist. The addition of levodopa could be postponed by many months or even several years. Therefore, these long-term studies of dopamine agonists support the initiation of a dopamine agonist instead of levodopa in an effort to postpone levodopa-related motor complications. This therapeutic approach may be particularly appropriate in PD patients with a long treatment horizon on the basis of age and general good health. The extension phase of the long-term study comparing pramipexole with levodopa is ongoing, and follow-up information may help to establish the value of this treatment strategy.

  3. Long Term Care Aide. Course Outline.

    ERIC Educational Resources Information Center

    Wilbee, Judy

    This course outline is intended to assist the instructor in the development of a curriculum for a long-term care aide program by specifying one component of the curriculum--the objectives. These objectives, or competencies expected as outcomes for student performance on completion of the program, describe the capabilities an individual must…

  4. Long-term lysimeter data on evapotranspiration

    USDA-ARS?s Scientific Manuscript database

    Long term crop evapotranspiration (ET) data measured using large weighing lysimeters have only been gathered in a few places in the world, yet are of great importance for ground truthing of many models of plant water use, mesoscale climate, remote sensing estimation of ET, climate change and climate...

  5. Who Recommends Long-Term Care Matters

    ERIC Educational Resources Information Center

    Kane, Robert L.; Bershadsky, Boris; Bershadsky, Julie

    2006-01-01

    Purpose: Making good consumer decisions requires having good information. This study compared long-term-care recommendations among various types of health professionals. Design and Methods: We gave randomly varied scenarios to a convenience national sample of 211 professionals from varying disciplines and work locations. For each scenario, we…

  6. Professionalism in Long-Term Care Settings

    ERIC Educational Resources Information Center

    Lubinski, Rosemary

    2006-01-01

    Speech-language pathologists who serve elders in a variety of long-term care settings have a variety of professional skills and responsibilities. Fundamental to quality service is knowledge of aging and communication changes and disorders associated with this process, institutional alternatives, and the changing nature of today's elders in…

  7. Evaluating Long-Term Disability Insurance Plans.

    ERIC Educational Resources Information Center

    Powell, Jan

    1992-01-01

    This report analyzes the factors involved in reviewing benefits and services of employer-sponsored group long-term disability plans for higher education institutions. Opening sections describe the evolution of disability insurance and its shape today. Further sections looks at the complex nature of "value" within a plan, relationship…

  8. LONG TERM HYDROLOGICAL IMPACT ASSESSMENT (LTHIA)

    EPA Science Inventory

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

  9. Long-Term Stability of Tutor Performance.

    ERIC Educational Resources Information Center

    Dolmans, Diana H. J. M.; And Others

    1996-01-01

    Examined the extent to which tutor ratings remained stable in the long term by evaluating 291 ratings of 140 tutors at Maastricht University in the Netherlands between 1992 and 1995. The results indicated that, if the aggregated score and overall judgement are used to interpret the precision of individual scores, four and two occasions,…

  10. Urethroplasty for hypospadias: long-term results.

    PubMed

    Glassman, C N; Machlus, B J; Kelalis, P P

    1980-06-01

    A retrospective study of patients who had undergone multi-staged hypospadias repair at the Mayo Clinic was undertaken to identify long-term problems associated with this surgery. Patients were queried concerning their satisfaction with quality of urinary stream; penile erection and ejaculation; sexual function and fertility; and cosmetic appearance.

  11. LONG TERM HYDROLOGICAL IMPACT ASSESSMENT (LTHIA)

    EPA Science Inventory

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

  12. Very Long Term Memory for Tacit Knowledge.

    ERIC Educational Resources Information Center

    Allen, Rhianon; Reber, Arthur S.

    1980-01-01

    Very long-term memory for abstract materials was examined for subjects who had served in a synthetic grammar learning experiment two years earlier. Knowledge of these grammars was retained. The form and structure of knowledge and the manner in which it is put to use remained similar to the original. (Author/RD)

  13. Long-term opioid therapy reconsidered.

    PubMed

    Von Korff, Michael; Kolodny, Andrew; Deyo, Richard A; Chou, Roger

    2011-09-06

    In the past 20 years, primary care physicians have greatly increased prescribing of long-term opioid therapy. However, the rise in opioid prescribing has outpaced the evidence regarding this practice. Increased opioid availability has been accompanied by an epidemic of opioid abuse and overdose. The rate of opioid addiction among patients receiving long-term opioid therapy remains unclear, but research suggests that opioid misuse is not rare. Recent studies report increased risks for serious adverse events, including fractures, cardiovascular events, and bowel obstruction, although further research on medical risks is needed. New data indicate that opioid-related risks may increase with dose. From a societal perspective, higher-dose regimens account for the majority of opioids dispensed, so cautious dosing may reduce both diversion potential and patient risks for adverse effects. Limiting long-term opioid therapy to patients for whom it provides decisive benefits could also reduce risks. Given the warning signs and knowledge gaps, greater caution and selectivity are needed in prescribing long-term opioid therapy. Until stronger evidence becomes available, clinicians should err on the side of caution when considering this treatment.

  14. Long-term fixed income market structure

    NASA Astrophysics Data System (ADS)

    Grilli, Luca

    2004-02-01

    Long-term fixed income market securities present a strong positive correlation in daily returns. By using a metrical approach and considering “modified” time series, I show how it is possible to show a more complex structure which depends strictly on the maturity date.

  15. Long-term function after restorative proctocolectomy.

    PubMed

    Wheeler, J M D; Banerjee, A; Ahuja, N; Jewell, D P; Mortensen, N J McC

    2005-05-01

    Early functional outcome after restorative proctocolectomy and formation of an ileoanal pouch is known to be good, but there are minimal data on the long-term function of the pouch. The aim of this study was to look at the long-term functional outcome in patients who had undergone restorative proctocolectomy and formation of an ileoanal pouch. A total of 151 consecutive patients (96 males, 55 females) who underwent ileoanal pouch surgery between April 1983 and May 1993 were identified. Functional outcomes from the previous 12 months were appraised by a standardized questionnaire. The median age at surgery was 31 years (range, 6-63 years), with a median follow-up of 142 months (range, 100-221 months). Eighteen patients have had their pouches excised, with another patient being defunctioned. Therefore 19 patients (13 percent) had suffered pouch failure. Altogether, 115 patients were available for follow-up, and 98 patients (85 percent) returned questionnaires. The median pouch-emptying frequency was five times (range, 1-17) during the day and one time (range, 0-6) at night. A total of 74 percent of patients had perfect continence during the day. Most of the patients had no life-style restrictions related to the pouch, and 98 percent of patients would recommend a pouch to others. Long-term functional outcome after ileoanal pouch surgery is good in most patients. For patients requiring proctocolectomy, ileoanal pouch surgery can now be recommended as an excellent long-term option.

  16. Long-Term Impacts of Educational Interventions

    ERIC Educational Resources Information Center

    Deming, David James

    2010-01-01

    The school accountability movement has led to a marked increase in the use of standardized test scores to measure school and teacher productivity, yet little is known about the correlation between test score gains and improvements in long-term outcomes. In the first chapter of my dissertation, I study the impact of a school choice policy in…

  17. Long-Term Stability of Tutor Performance.

    ERIC Educational Resources Information Center

    Dolmans, Diana H. J. M.; And Others

    1996-01-01

    Examined the extent to which tutor ratings remained stable in the long term by evaluating 291 ratings of 140 tutors at Maastricht University in the Netherlands between 1992 and 1995. The results indicated that, if the aggregated score and overall judgement are used to interpret the precision of individual scores, four and two occasions,…

  18. Who Recommends Long-Term Care Matters

    ERIC Educational Resources Information Center

    Kane, Robert L.; Bershadsky, Boris; Bershadsky, Julie

    2006-01-01

    Purpose: Making good consumer decisions requires having good information. This study compared long-term-care recommendations among various types of health professionals. Design and Methods: We gave randomly varied scenarios to a convenience national sample of 211 professionals from varying disciplines and work locations. For each scenario, we…

  19. Long-term disability in anxiety disorders.

    PubMed

    Hendriks, Sanne M; Spijker, Jan; Licht, Carmilla M M; Hardeveld, Florian; de Graaf, Ron; Batelaan, Neeltje M; Penninx, Brenda W J H; Beekman, Aartjan T F

    2016-07-19

    This longitudinal study aims to investigate differences in long-term disability between social anxiety disorder (SAD), panic disorder with agoraphobia (PDA), panic disorder without agoraphobia (PD), generalized anxiety disorder (GAD) and multiple anxiety disorders (multiple AD), focusing on the effects of different course trajectories (remission, recurrence and chronic course) and specific symptom dimensions (anxiety arousal and avoidance behaviour). Data were used from participants with no psychiatric diagnosis (healthy controls, n = 647) or with a current anxiety disorder (SAD, n = 191; PDA, n = 90; PD, n = 84; GAD, n = 110; multiple AD, n = 480). Severity of anxiety arousal and avoidance behaviour symptoms was measured using the Beck Anxiety Inventory and the Fear Questionnaire. The World Health Organization Disability Assessment Schedule II was used to measure disability. Long-term disability was most prevalent in participants with SAD and multiple AD, and lowest in PDA and PD. GAD had an intermediate position. Anxiety arousal and avoidance behaviour were associated with more long-term disability in anxiety disorders than course trajectories. Various anxiety disorders have different disability levels over 4 years of time, therefore diagnostic distinction is important for treatment focus. Anxiety arousal and avoidance behaviour are major predictors for long-term disability in anxiety disorders.

  20. Long-Term Care Research and Policy

    ERIC Educational Resources Information Center

    Kemper, Peter

    2003-01-01

    This article provides a framework for understanding how long-term care (LTC) research contributes to policy, develops a typology of research contributions to policy with examples of each type, and suggests ways to ensure that contributions continue in the future. The article draws on in-depth interviews with LTC experts working at the interface…

  1. The long term characteristics of greenschist

    NASA Astrophysics Data System (ADS)

    Jang, Bo-An

    2016-04-01

    The greenschist in the Jinping II Hydropower Station in southwest China exhibits continuous creep behaviour because of the geological conditions in the region. This phenomenon illustrates the time-dependent deformation and progressive damage that occurs after excavation. In this study, the responses of greenschist to stress over time were determined in a series of laboratory tests on samples collected from the access tunnel walls at the construction site. The results showed that the greenschist presented time-dependent behaviour under long-term loading. The samples generally experienced two stages: transient creep and steady creep, but no accelerating creep. The periods of transient creep and steady creep increased with increasing stress levels. The long-term strength of the greenschist was identified based on the variation of creep strain and creep rate. The ratio of long-term strength to conventional strength was around 80% and did not vary much with confining pressures. A quantitative method for predicting the failure period of greenschist, based on analysis of the stress-strain curve, is presented and implemented. At a confining pressure of 40 MPa, greenschist was predicted to fail in 5000 days under a stress of 290 MPa and to fail in 85 days under the stress of 320 MPa, indicating that the long-term strength identified by the creep rate and creep strain is a reliable estimate.

  2. Navstar Global Positioning System (GPS) clock program: Present and future

    NASA Technical Reports Server (NTRS)

    Tennant, D. M.

    1981-01-01

    Global Positioning System (GPS) program status are discussed and plans for ensuring the long term continuation of the program are presented. Performance of GPS clocks is presented in terms of on orbit data as portrayed by GPS master control station kalman filter processing. The GPS Clock reliability program is reviewed in depth and future plans fo the overall clock program are published.

  3. Workshop on long-term contraceptives.

    PubMed

    1996-01-01

    The National Population Council Secretariat (NPCS) of Ghana held a three-day workshop on long-term contraceptives in 1996 in collaboration with the Ministry of Health, the Association of Voluntary Surgical Contraception, and the Johns Hopkins Population Communication Services. The session was funded by USAID. The executive director of NPCS, Dr. Richard Turkson, said that the slow rate of contraceptive acceptance was an obstacle to population control despite political concern that rapid population growth exerted an adverse impact on the economy. Only 10% of married women were using long-term or permanent methods of contraception. The hope was voiced that the participants would devise practical and cost-effective education, information, and communication (IEC) strategies to boost the demand for long-term contraceptive methods among sexually active people in Ghana. It was essential that these strategies and activities were based on a realist assessment of the demographic and social situation of the country. The examination of case studies in cultures similar to Ghana would also offer valuable lessons. The factors that hinder the acceptance of long-term methods include misconceptions, myths, and false rumors rooted in a general lack of knowledge among the people. Participants were urged to come up with strategies to counter these problems, and service providers were encouraged to improve their knowledge about contraceptive methods and counseling skills. Male involvement in contraception was also advocated. Statistics show that most Ghanians practicing contraception were using short-term methods such as foaming tablets, pills, and condoms. However, it is necessary to shift to long-term methods such as injectables, implants, and sterilization in order to achieve significant reductions in fertility.

  4. Long-term biological investigations in space.

    PubMed

    Lotz, R G; Fuchs, H; Bertsche, U

    1975-01-01

    Missions in space within the next two decades will be of longer duration than those carried out up to the present time, and the effects of such long-term flights on biological organisms are unknown. Results of biological experiments that have been performed to date cannot be extrapolated to results in future flights because of the unknown influence of adaptation over a long period of time. Prior experiments with Axolotl, fishes, and vertebrates by our research team (in part with sounding rockets) showed that these specimens did not appear to be suitable for long-term missions on which minimization of expense, technique, and energy is required. Subsequent investigations have shown the suitability of the leech (Hirudo medicinalis), which consumes blood of mammals up to ten times its own weight (1 g) and can live more than 2 years without further food supply. Emphasis in the experiments with Hirudo medicinalis is placed on metabolic rhythm and motility. Resorption and diffusion in tissue, development, and growth under long-term effects of cosmic proton radiation and zero-gravity are other focal points. The constancy of cellular life in the mature animals is a point in favor of these specimens. We have also taken into account the synergistic effects of the space environment on the problems just mentioned. The life-support system constructed for the leech has been tested successfully in four sounding rocket flights and, on that basis, has been prepared for a long-term mission. Long-term investigations out of the terrestrial biosphere will provide us with information concerning the degree of adaptation of certain physiological and biochemical functions and as to what extent biological readjustment or repair processes can occur under the specific stress conditions of space flight.

  5. Long-Term Hearing Results After Ossiculoplasty.

    PubMed

    Cox, Matthew D; Trinidade, Aaron; Russell, James Shep; Dornhoffer, John L

    2017-04-01

    To determine if the OOPS index is predictive of long-term hearing results after ossiculoplasty. Case series with retrospective chart review. Tertiary care otology practice. Adult and pediatric patients (3-88 years of age). Ossiculoplasty with cartilage tympanoplasty, with or without mastoidectomy. Primary outcome measures included short-term hearing results (pure-tone average air-bone gap [PTA-ABG] measured between 60 days and 1 year after surgery), long-term hearing results (PTA-ABG measured ≥5 years after surgery), and the rate of successful ABG closure to ≤20 dB. Secondary measures included the need for revision surgery, delayed tympanic membrane graft failure, worsening conductive hearing loss (after an initially satisfactory hearing result), and recurrence of cholesteatoma. There was no significant difference between adults and children for short-term hearing results (average post-op PTA-ABG was 18.9 dB vs. 19.8 dB, respectively; p = 0.544), long-term hearing results (average final PTA-ABG was 19.3 dB vs. 19.4 dB, respectively; p = 0.922), or rate of ABG closure to less than 20 dB (63.1% vs. 58.0%, p = 0.282). Spearman's rank-order correlation (ρ) identified a strong positive correlation between OOPS index score and average post-operative PTA-ABG (ρ = 0.983; p < 0.001; 2-tailed), as well as average long-term PTA-ABG (ρ = 0.950, p < 0.001; 2-tailed). The OOPS index makes it possible to accurately prognosticate hearing outcomes in adult and pediatric patients undergoing ossiculoplasty in both the short term and the long term.

  6. Tracking Architecture Based on Dual-Filter with State Feedback and Its Application in Ultra-Tight GPS/INS Integration.

    PubMed

    Zhang, Xi; Miao, Lingjuan; Shao, Haijun

    2016-05-02

    If a Kalman Filter (KF) is applied to Global Positioning System (GPS) baseband signal preprocessing, the estimates of signal phase and frequency can have low variance, even in highly dynamic situations. This paper presents a novel preprocessing scheme based on a dual-filter structure. Compared with the traditional model utilizing a single KF, this structure avoids carrier tracking being subjected to code tracking errors. Meanwhile, as the loop filters are completely removed, state feedback values are adopted to generate local carrier and code. Although local carrier frequency has a wide fluctuation, the accuracy of Doppler shift estimation is improved. In the ultra-tight GPS/Inertial Navigation System (INS) integration, the carrier frequency derived from the external navigation information is not viewed as the local carrier frequency directly. That facilitates retaining the design principle of state feedback. However, under harsh conditions, the GPS outputs may still bear large errors which can destroy the estimation of INS errors. Thus, an innovative integrated navigation filter is constructed by modeling the non-negligible errors in the estimated Doppler shifts, to ensure INS is properly calibrated. Finally, field test and semi-physical simulation based on telemetered missile trajectory validate the effectiveness of methods proposed in this paper.

  7. Tracking Architecture Based on Dual-Filter with State Feedback and Its Application in Ultra-Tight GPS/INS Integration

    PubMed Central

    Zhang, Xi; Miao, Lingjuan; Shao, Haijun

    2016-01-01

    If a Kalman Filter (KF) is applied to Global Positioning System (GPS) baseband signal preprocessing, the estimates of signal phase and frequency can have low variance, even in highly dynamic situations. This paper presents a novel preprocessing scheme based on a dual-filter structure. Compared with the traditional model utilizing a single KF, this structure avoids carrier tracking being subjected to code tracking errors. Meanwhile, as the loop filters are completely removed, state feedback values are adopted to generate local carrier and code. Although local carrier frequency has a wide fluctuation, the accuracy of Doppler shift estimation is improved. In the ultra-tight GPS/Inertial Navigation System (INS) integration, the carrier frequency derived from the external navigation information is not viewed as the local carrier frequency directly. That facilitates retaining the design principle of state feedback. However, under harsh conditions, the GPS outputs may still bear large errors which can destroy the estimation of INS errors. Thus, an innovative integrated navigation filter is constructed by modeling the non-negligible errors in the estimated Doppler shifts, to ensure INS is properly calibrated. Finally, field test and semi-physical simulation based on telemetered missile trajectory validate the effectiveness of methods proposed in this paper. PMID:27144570

  8. A Search for Long-term Slow Slip Along the Cascadia Subduction Zone

    NASA Astrophysics Data System (ADS)

    Nuyen, C.; Schmidt, D. A.

    2016-12-01

    Japan's Nankai Trough and the Cascadia Subduction Zone are often compared as analogous systems due to their striking similarities, which include relatively high thermal gradients, young incoming plates, and the occurrence of short-term slow slip episodes (SSEs). However, a lack of long-term SSEs in Cascadia sets it apart from Nankai, which experiences both short- and long-term SSEs. This disparity between Cascadia and Nankai begs the question of whether long-term SSEs are in fact absent in Cascadia. We examine GPS data from the PBO and PANGA networks to determine whether or not Cascadia has hosted a long-term SSE in the past 20 years. A preliminary review of the time series does not reveal any large-scale multi-year transients, such as has been documented in Japan and Alaska where over 5 cm of surface displacement is seen over multiple years. In order to more clearly recognize possible small amplitude long-term SSEs in Cascadia, the GPS data are reduced as follows: time series are cleaned by removing (1) continental water loading terms, (2) transient displacements of known short-term SSEs, and (3) common mode signals that span the network. After cleaning, the GPS data are manually inspected for coherent trends between stations. To further identify small amplitude slip events that persist for months-to-years, we invert the cleaned time series in Cascadia for fault slip using a principle component analysis-based inversion method. We also perform a suite of synthetic forward models to better understand how a long-term slow slip event might appear in the time series. Results from this research have direct implications for Cascadia in terms of moment release, stress redistributions, and seismic cycles. In a broader sense, these results also influence the global knowledge of SSEs by giving a better understanding of the full range of slip modes in Cascadia.

  9. Long-term consequences of foodborne infections.

    PubMed

    Batz, Michael B; Henke, Evan; Kowalcyk, Barbara

    2013-09-01

    Foodborne infections with Campylobacter, E. coli O157:H7, Listeria monocytogenes, Salmonella, Shigella, Toxoplasma gondii, and other pathogens can result in long-term sequelae to numerous organ systems. These include irritable bowel syndrome, inflammatory bowel disease, reactive arthritis, hemolytic uremic syndrome, chronic kidney disease, Guillain-Barré Syndrome, neurological disorders from acquired and congenital listeriosis and toxoplasmosis, and cognitive and developmental deficits due to diarrheal malnutrition or severe acute illness. A full understanding of the long-term sequelae of foodborne infection is important both for individual patient management by clinicians, as well as to inform food safety and public health decision making. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Case presentation: long-term treatment.

    PubMed

    Glucksman, Myron L

    2013-01-01

    The long-term (14 years) psychodynamic psychotherapy and pharmacotherapy of a depressed, suicidal, self-mutilating female patient is described. Her diagnoses included Chronic Posttraumatic Stress Disorder, Borderline Personality Disorder, and Recurrent Major Depression. Treatment was punctuated with repeated hospitalizations for self-mutilation (cutting) and suicidal ideation. A major determinant for her psychopathology was sexual abuse by her father from ages 6 to 14. This resulted in feelings of guilt and rage that she repressed and acted out through self-mutilating and suicidal behavior. A prolonged negative transference gradually became ambivalent, then positive. This was associated with her internalization of the healing qualities of the therapeutic relationship. She also gained insight into the reasons for her need to punish herself. Her initial self-representation as unworthy and bad was transformed into perceiving herself as a worthwhile, loving person. This case illustrates the role of long-term treatment for a complex, life-threatening, psychiatric disorder.

  11. [Ambulatory long-term EEG monitors].

    PubMed

    John, K; Komärek, V; Lehovský, M

    1990-06-01

    Ambulatory EEG monitoring is indicated in patients with attacks of uncertain origin. The method is useful to distinguish non-epileptic and epileptic attacks and to differentiate the kind of epileptic seizures which is important for the choice of antiepileptic drugs and for prognosis. It is necessary to describe in detail behaviour and seizures of patient during monitoring. EEG long term monitoring is only useful if attacks were seen frequently, at least once or twice a week.

  12. LOP - Long-Term Orbit Predictor

    NASA Technical Reports Server (NTRS)

    Kwok, Johnny H.

    1992-01-01

    Long-Term Orbit Preditor (LOP) trajectory-propagation computer program is useful tool in analysis of lifetime of orbiting spacecraft. Suitable for studying planetary-orbit missions with reconnaissance (flyby) and exploratory (mapping) trajectories. Includes sample data for study of drift cycle of geosynchronous station, strategy for radar mapping of Venus, frozen orbit about Mars, and orbit characterized by repeating ground trace. Executed faster than such programs based on Cowell's method. Written in FORTRAN 77.

  13. Long term economic relationships from cointegration maps

    NASA Astrophysics Data System (ADS)

    Vicente, Renato; Pereira, Carlos de B.; Leite, Vitor B. P.; Caticha, Nestor

    2007-07-01

    We employ the Bayesian framework to define a cointegration measure aimed to represent long term relationships between time series. For visualization of these relationships we introduce a dissimilarity matrix and a map based on the sorting points into neighborhoods (SPIN) technique, which has been previously used to analyze large data sets from DNA arrays. We exemplify the technique in three data sets: US interest rates (USIR), monthly inflation rates and gross domestic product (GDP) growth rates.

  14. Long-term sequelae of electrical injury

    PubMed Central

    Wesner, Marni L.; Hickie, John

    2013-01-01

    Abstract Objective To summarize the current evidence-based knowledge about the long-term sequelae of injuries from electrical current. Quality of evidence MEDLINE was searched for English-language articles published in the past 20 years using the following search terms: electrical, injuries, wound, trauma, accident, sequelae, long-term, follow-up, and aftereffects. For obvious reasons, it is unethical to randomly study electrical injury in controlled clinical trials. By necessity, this topic is addressed in less-rigorous observational and retrospective work and case studies. Therefore, the strength of the literature pertaining to the long-term sequelae of electrical injury is impaired by the necessity of retrospective methods and case studies that typically describe small cohorts. Main message There are 2 possible consequences of electrical injury: the person either survives or dies. For those who survive electrical injury, the immediate consequences are usually obvious and often require extensive medical intervention. The long-term sequelae of the electrical injury might be more subtle, pervasive, and less well defined, but can include neurologic, psychological, and physical symptoms. In the field of compensation medicine, determining causation and attributing outcome to an injury that might not result in objective clinical findings becomes a considerable challenge. Conclusion The appearance of these consequences of electrical injury might be substantially delayed, with onset 1 to 5 or more years after the electrical injury. This poses a problem for patients and health care workers, making it hard to ascribe symptoms to a remote injury when they might not arise until well after the incident event. PMID:24029506

  15. Breakthroughs in long term care design.

    PubMed

    Hiatt, L

    1991-01-01

    In summary, here is what design is trying to accomplish in long term care facilities: Functional access; Privacy as entitlement; Sensory optimization to improve vision and hearing; Reduced walking and wheeling distances that still allow people to be mobile; Effective or functional placement of space and equipment; The option of smaller scale, so neither residents nor staff feel like they are hanging out with a unit full of, perhaps 68, people all the time; Flexibility and adaptability

  16. Long-term course of opioid addiction.

    PubMed

    Hser, Yih-Ing; Evans, Elizabeth; Grella, Christine; Ling, Walter; Anglin, Douglas

    2015-01-01

    Opioid addiction is associated with excess mortality, morbidities, and other adverse conditions. Guided by a life-course framework, we review the literature on the long-term course of opioid addiction in terms of use trajectories, transitions, and turning points, as well as other factors that facilitate recovery from addiction. Most long-term follow-up studies are based on heroin addicts recruited from treatment settings (mostly methadone maintenance treatment), many of whom are referred by the criminal justice system. Cumulative evidence indicates that opioid addiction is a chronic disorder with frequent relapses. Longer treatment retention is associated with a greater likelihood of abstinence, whereas incarceration is negatively related to subsequent abstinence. Over the long term, the mortality rate of opioid addicts (overdose being the most common cause) is about 6 to 20 times greater than that of the general population; among those who remain alive, the prevalence of stable abstinence from opioid use is low (less than 30% after 10-30 years of observation), and many continue to use alcohol and other drugs after ceasing to use opioids. Histories of sexual or physical abuse and comorbid mental disorders are associated with the persistence of opioid use, whereas family and social support, as well as employment, facilitates recovery. Maintaining opioid abstinence for at least five years substantially increases the likelihood of future stable abstinence. Recent advances in pharmacological treatment options (buprenorphine and naltrexone) include depot formulations offering longer duration of medication; their impact on the long-term course of opioid addiction remains to be assessed.

  17. Development of a hybrid solar tracking device using a GPS and a photo-sensor capable of operating at low solar radiation intensity

    NASA Astrophysics Data System (ADS)

    Lee, Hyo Geun; Kim, Sang Suk; Kim, Sung Jo; Park, Su-Jin; Yun, Chang-wuk; Im, Gil-pyeong

    2015-09-01

    The PhotoVoltaic System, which is and environmentally-sound source of sustainable energy among most representaion of what alternative energy resources, is in the limelight [1]. Especially, the concentration photovoltaic system (CPV) is more effective than the general photovoltaic system. However, In existing CPV systems tracking the sun position when insolation is low or rapidly changing due to clouds and fog is pratically impossible. For this reason, obtain satisfactory power generation is difficult. In this reserely a hybrid method for tracking the sun's altitude/latitude angles by combining a GPS sensor with an existing tracking system was developed. This study tested the accuracy of tracking when the hybrid tracking system was applied to a 5 kW photovoltaic system, Currently, this study is performing tests to demonstrate the tracking accuracy by testing CPV modules instead of applying general PV modules for the system. In the future, the application of this system in a define MCPV(MCPV) module will improve the efficiency of power generation.

  18. Infective endocarditis: determinants of long term outcome

    PubMed Central

    Netzer, R O M; Altwegg, S C; Zollinger, E; Täuber, M; Carrel, T; Seiler, C

    2002-01-01

    Objective: To evaluate predictors of long term prognosis in infective endocarditis. Design: Retrospective cohort study. Setting: Tertiary care centre. Patients: 212 consecutive patients with infective endocarditis between 1980 and 1995 Main outcome measures: Overall and cardiac mortality; event-free survival; and the following events: recurrence, need for late valve surgery, bleeding and embolic complications, cerebral dysfunction, congestive heart failure. Results: During a mean follow up period of 89 months (range 1–244 months), 56% of patients died. In 180 hospital survivors, overall and cardiac mortality amounted to 45% and 24%, respectively. By multivariate analysis, early surgical treatment, infection by streptococci, age < 55 years, absence of congestive heart failure, and > 6 symptoms or signs of endocarditis during active infection were predictive of improved overall long term survival. Independent determinants of event-free survival were infection by streptococci and age < 55 years. Event-free survival was 17% at the end of follow up both in medically–surgically treated patients and in medically treated patients. Conclusions: Long term survival following infective endocarditis is 50% after 10 years and is predicted by early surgical treatment, age < 55 years, lack of congestive heart failure, and the initial presence of more symptoms of endocarditis. PMID:12067947

  19. Long-term OH variability of Miras

    NASA Astrophysics Data System (ADS)

    Etoka, S.; Le Squeren, A. M.

    2000-10-01

    We present here the results and interpretation of a long-term OH variability program conducted with the French {Nançay} Radiotelescope from 1980 to 1995. It concerns seven Mira stars: R Aql, RS Vir, S CrB, R LMi, RR Aql, U Her and UX Cyg. This study deals with the three OH maser lines observed in the Miras at 1612, 1665 and 1667 MHz. These OH variable stars have periods ranging from 290 to 580 days. The study presents the first insight of the long-term temporal behaviour of OH integrated flux variations as well as spectral component variations. The main aims are to determine the temporal behaviour of the OH maser emission and the longevity and variability of the spectral components. We find that the shapes of the OH curve are closer to the IR than the optical shapes and that the emissions at 1665 and 1667 MHz have a very similar behaviour while the emission at 1612 MHz behaves differently. The 1612 MHz emission shows smoother temporal variations and greater component longevity than the main line emission, leading to the conclusion that the 1612 MHz emission is coming from an outer part of the circumstellar shell and is more saturated than the main line emission. The study also shows the existence of inhomogeneities, especially differences between the front and back parts of the shell can be seen, and that OH variability curves undergo long term variations over several cycles.

  20. Electrodes for long-term esophageal electrocardiography.

    PubMed

    Niederhauser, Thomas; Haeberlin, Andreas; Marisa, Thanks; Jungo, Michael; Goette, Josef; Jacomet, Marcel; Abacherli, Roger; Vogel, Rolf

    2013-09-01

    The emerging application of long-term and high-quality ECG recording requires alternative electrodes to improve the signal quality and recording capability of surface skin electrodes. The esophageal ECG has the potential to overcome these limitations but necessitates novel recorder and lead designs. The electrode material is of particular interest, since the material has to ensure conflicting requirements like excellent biopotential recording properties and inertness. To this end, novel electrode materials like PEDOT and silver-PDMS as well as established electrode materials such as stainless steel, platinum, gold, iridium oxide, titanium nitride, and glassy carbon were investigated by long-term electrochemical impedance spectroscopy and model-based signal analysis using the derived in vitro interfacial properties in conjunction with a dedicated ECG amplifier. The results of this novel approach show that titanium nitride and iridium oxide featuring microstructured surfaces did not degrade when exposed to artificial acidic saliva. These materials provide low electrode potential drifts and insignificant signal distortion superior to surface skin electrodes making them compatible with accepted standards for ambulatory ECG. They are superior to the noble and polarizable metals such as platinum, silver, and gold that induced more signal distortions and are superior to esophageal stainless steel electrodes that corrode in artificial saliva. The study provides rigorous criteria for the selection of electrode materials for prolonged ECG recording by combining long-term in vitro electrode material properties with ECG signal quality assessment.

  1. Long-term prophylaxis in bipolar disorder.

    PubMed

    Taylor, Matthew J; Goodwin, Guy M

    2006-01-01

    Bipolar disorder is a major cause of disability, and the prevention of relapse is a key management goal. Pharmacological interventions, effectively delivered through enhanced clinical care, are central to long-term management. This article summarises the available evidence for a range of pharmacological options, and provides guidance on common issues in clinical management in line with current practice guidelines. The use of medications for long-term prophylaxis should be considered in all patients meeting criteria for bipolar I disorder. Increasing high-quality evidence from randomised trials informs management decisions relating to both novel agents, such as lamotrigine and olanzapine, and longer-established therapies, such as lithium and valproate, in monotherapy. Medications taken long-term in bipolar disorder differ in the extent to which they protect against manic and depressive relapse. Consequently, the emerging challenge is to understand how combination treatments can enhance efficacy and effectiveness based on data from controlled trials rather than random polypharmacy. Clinical care can be enhanced with effective education about the illness, and the use of strategies to improve treatment adherence and the recognition and management of stressors or prodromal symptoms. Where available, a range of specific psychological interventions can be effective as an adjunct to medication. When discontinuation of prophylaxis is necessary, gradual tapering of dose over weeks or months is recommended.

  2. Long term therapy of generalized anxiety disorder.

    PubMed

    Rouillon, Frédéric

    2004-04-01

    Generalized anxiety disorder (GAD) is a common (lifetime prevalence: 5.1%), recurrent condition, which often heralds other psychiatric disorders, notably depression. As by definition it is a disorder progressing over months, treatment should be designed on a long term basis. And yet, few studies have been conducted beyond the classical 6-8 weeks characterizing the acute treatment phase. This is especially true of anxiolytics, but also of antidepressants, with the exception of paroxetine and venlafaxine, which are the only drugs approved in this indication in Western countries. The efficacy of psychotherapy, notably relaxation and cognitive-behavioral therapy, is established in the treatment of GAD, but its preferred indications and possible combination with antidepressants are still to be specified. Long term, not to say very long term studies of GAD, as well as depression, will still be required in the future to improve its management and specify therapeutic modalities (combination treatment, optimal duration, continuous or intermittent therapy, choice of psychotherapeutic techniques or agents, em leader ). Early and adequately prolonged treatment should not only result in more numerous remission periods, but also in decreased frequency of co-morbidities whether depressive, addictive, or of another nature, and should also reduce the social impact of GAD.

  3. Titanium for long-term tritium storage

    SciTech Connect

    Heung, L.K.

    1994-12-01

    Due to the reduction of nuclear weapon stockpile, there will be an excess of tritium returned from the field. The excess tritium needs to be stored for future use, which might be several years away. A safe and cost effective means for long term storage of tritium is needed. Storing tritium in a solid metal tritide is preferred to storing tritium as a gas, because a metal tritide can store tritium in a compact form and the stored tritium will not be released until heat is applied to increase its temperature to several hundred degrees centigrade. Storing tritium as a tritide is safer and more cost effective than as a gas. Several candidate metal hydride materials have been evaluated for long term tritium storage. They include uranium, La-Ni-Al alloys, zirconium and titanium. The criteria used include material cost, radioactivity, stability to air, storage capacity, storage pressure, loading and unloading conditions, and helium retention. Titanium has the best combination of properties and is recommended for long term tritium storage.

  4. A Long-Term Counterinsurgency Strategy

    DTIC Science & Technology

    2010-01-01

    strategic utility. “That utility reposes most essentially in two qualities, economy of force and expansion of strategic choice,” asserts Colin Gray...advent of INS/GPS weapons with programmable attack azimuth and impact angle capabilities independent of delivery platform and profile has virtually

  5. Feasibility study on the spatial and temporal movement of Samburu's cattle and wildlife in Kenya using GPS radio-tracking, remote sensing and GIS.

    PubMed

    Raizman, E A; Rasmussen, H Barner; King, L E; Ihwagi, F W; Douglas-Hamilton, I

    2013-08-01

    The study was conducted to assess the technical feasibility of studying the spatial and temporal interaction of traditionally herded livestock and wildlife using global positioning system (GPS) tracking technology in Northern Kenya. Two types of collars were used on nine cows: radio frequency and global system for mobile communications (GSM) collars and GPS-satellite (SAT) collars. Full results of cattle tracking were available for eight cows (3 GSM and 5 SAT) tracked between July 2008 and September 2010. A cumulative total of 1556 tracking days was recorded over the 17 month period. On average cows walked 10,203 m/day (average total monthly distance walked was 234 km). Significant seasonal differences were found; on average cows walked 9.607 m and 10,392 m per day in the rainy and the dry seasons, respectively. This difference was also significant for total monthly and daily distance walked between the dry and the rainy season. On average cows walked daily 9607 m and 10,392 m on the rainy and the dry season respectively. During the dry months a 48 h cycle was observed with cows walking 15-25 km to water every 2nd day but only 5-8 km/day between watering days. There was a 24% overlap of cattle range with both elephants and zebras. This study demonstrated the feasibility of tracking cattle using radio collars. It shows the complexity of spatial use by cattle and wildlife. Such information can be used to understand the dynamics of disease transmission between livestock and wildlife.

  6. Timber beams subjected to long - term loading

    NASA Astrophysics Data System (ADS)

    Sógel, K.

    2010-09-01

    Wood is a significant structural material, which is often used for timber bearing structures. Elements of timber structures must especially satisfy safety requirements, which are expressed by the ultimate limit states in the established standards. The structure must also satisfy the serviceability limit states. Local and global deformations make it impossible for the structure to serve the purpose it was designed for. It is important to take the deflections and their possible increase into account in the design to provide a structure which can be used during the whole period of service. Based on earlier examinations, it is known that a timber element over the course of long-term loading shows creep behavior. The structure of wood is able to adapt to the conditions of the surrounding environment. The properties of wood are especially affected by the relative humidity of the air and then by the type, intensity and duration of the loading. The most important factors affecting the serviceability of timber structures are volume changes caused by humidity and additional deflections caused by the effects of long-term loading. These phenomena emphasize the importance of serviceability limit states for timber structures. The paper deals with a long-term experimental investigation of timber girders that are currently often used. The aim was to obtain the deflection curves and mark the time dependence and the final deflections. The paper will also define the approximations for simulating the time-dependent deflections and obtain the creep coefficients for calculating the final deflections of the girders investigated.

  7. Long-Term Recency in Anterograde Amnesia

    PubMed Central

    Talmi, Deborah; Caplan, Jeremy B.; Richards, Brian; Moscovitch, Morris

    2015-01-01

    Amnesia is usually described as an impairment of a long-term memory (LTM) despite an intact short-term memory (STM). The intact recency effect in amnesia had supported this view. Although dual-store models of memory have been challenged by single-store models based on interference theory, this had relatively little influence on our understanding and treatment of amnesia, perhaps because the debate has centred on experiments in the neurologically intact population. Here we tested a key prediction of single-store models for free recall in amnesia: that people with amnesia will exhibit a memory advantage for the most recent items even when all items are stored in and retrieved from LTM, an effect called long-term recency. People with amnesia and matched controls studied, and then free-recalled, word lists with a distractor task following each word, including the last (continual distractor task, CDFR). This condition was compared to an Immediate Free Recall (IFR, no distractors) and a Delayed Free Recall (DFR, end-of-list distractor only) condition. People with amnesia demonstrated the full long-term recency pattern: the recency effect was attenuated in DFR and returned in CDFR. The advantage of recency over midlist items in CDFR was comparable to that of controls, confirming a key prediction of single-store models. Memory deficits appeared only after the first word recalled in each list, suggesting the impairment in amnesia may emerge only as the participant’s recall sequence develops, perhaps due to increased susceptibility to output interference. Our findings suggest that interference mechanisms are preserved in amnesia despite the overall impairment to LTM, and challenge strict dual-store models of memory and their dominance in explaining amnesia. We discuss the implication of our findings for rehabilitation. PMID:26046770

  8. Long-Term Recency in Anterograde Amnesia.

    PubMed

    Talmi, Deborah; Caplan, Jeremy B; Richards, Brian; Moscovitch, Morris

    2015-01-01

    Amnesia is usually described as an impairment of a long-term memory (LTM) despite an intact short-term memory (STM). The intact recency effect in amnesia had supported this view. Although dual-store models of memory have been challenged by single-store models based on interference theory, this had relatively little influence on our understanding and treatment of amnesia, perhaps because the debate has centred on experiments in the neurologically intact population. Here we tested a key prediction of single-store models for free recall in amnesia: that people with amnesia will exhibit a memory advantage for the most recent items even when all items are stored in and retrieved from LTM, an effect called long-term recency. People with amnesia and matched controls studied, and then free-recalled, word lists with a distractor task following each word, including the last (continual distractor task, CDFR). This condition was compared to an Immediate Free Recall (IFR, no distractors) and a Delayed Free Recall (DFR, end-of-list distractor only) condition. People with amnesia demonstrated the full long-term recency pattern: the recency effect was attenuated in DFR and returned in CDFR. The advantage of recency over midlist items in CDFR was comparable to that of controls, confirming a key prediction of single-store models. Memory deficits appeared only after the first word recalled in each list, suggesting the impairment in amnesia may emerge only as the participant's recall sequence develops, perhaps due to increased susceptibility to output interference. Our findings suggest that interference mechanisms are preserved in amnesia despite the overall impairment to LTM, and challenge strict dual-store models of memory and their dominance in explaining amnesia. We discuss the implication of our findings for rehabilitation.

  9. Using a Partial Sum Method and GPS Tracking Data to Identify Area Restricted Search by Artisanal Fishers at Moored Fish Aggregating Devices in the Commonwealth of Dominica

    PubMed Central

    Alvard, Michael; Carlson, David; McGaffey, Ethan

    2015-01-01

    Foragers must often travel from a central place to exploit aggregations of prey. These patches can be identified behaviorally when a forager shifts from travel to area restricted search, identified by a decrease in speed and an increase in sinuosity of movement. Faster, more directed movement is associated with travel. Differentiating foraging behavior at patches from travel to patches is important for a variety of research questions and has now been made easier by the advent of small, GPS devices that can track forager movement with high resolution. In the summer and fall of 2012, movement data were collected from GPS devices placed on foraging trips originating in the artisanal fishing village of Desa Ikan (pseudonym), on the east coast of the Caribbean island nation of the Commonwealth Dominica. Moored FADs are human-made structures anchored to the ocean floor with fish attraction material on or near the surface designed to effectively create a resource patch. The ultimate goal of the research is to understand how property rights are emerging after the introduction of fish aggregating device (FAD) technology at the site in 1999. This paper reports on research to identify area-restricted search foraging behavior at FAD patches. For 22 foraging trips simultaneous behavioral observations were made to ground-truth the GPS movement data. Using a cumulative sum method, area restricted search was identified as negative deviations from the mean travel speed and the method was able to correctly identify FAD patches in every case. PMID:25647288

  10. Using a partial sum method and GPS tracking data to identify area restricted search by artisanal fishers at moored fish aggregating devices in the Commonwealth of Dominica.

    PubMed

    Alvard, Michael; Carlson, David; McGaffey, Ethan

    2015-01-01

    Foragers must often travel from a central place to exploit aggregations of prey. These patches can be identified behaviorally when a forager shifts from travel to area restricted search, identified by a decrease in speed and an increase in sinuosity of movement. Faster, more directed movement is associated with travel. Differentiating foraging behavior at patches from travel to patches is important for a variety of research questions and has now been made easier by the advent of small, GPS devices that can track forager movement with high resolution. In the summer and fall of 2012, movement data were collected from GPS devices placed on foraging trips originating in the artisanal fishing village of Desa Ikan (pseudonym), on the east coast of the Caribbean island nation of the Commonwealth Dominica. Moored FADs are human-made structures anchored to the ocean floor with fish attraction material on or near the surface designed to effectively create a resource patch. The ultimate goal of the research is to understand how property rights are emerging after the introduction of fish aggregating device (FAD) technology at the site in 1999. This paper reports on research to identify area-restricted search foraging behavior at FAD patches. For 22 foraging trips simultaneous behavioral observations were made to ground-truth the GPS movement data. Using a cumulative sum method, area restricted search was identified as negative deviations from the mean travel speed and the method was able to correctly identify FAD patches in every case.

  11. USNO GPS program

    NASA Technical Reports Server (NTRS)

    Putkovich, K.

    1981-01-01

    Initial test results indicated that the Global Positioning System/Time Transfer Unit (GPS/TTU) performed well within the + or - 100 nanosecond range required by the original system specification. Subsequent testing involved the verification of GPS time at the master control site via portable clocks and the acquisition and tracking of as many passes of the space vehicles currently in operation as possible. A description and discussion of the testing, system modifications, test results obtained, and an evaluation of both GPS and the GPS/TTU are presented.

  12. Long-term management of prolactinomas.

    PubMed

    Schlechte, Janet A

    2007-08-01

    Prolactinomas are a frequent cause of gonadal dysfunction and infertility, especially in young women. The regulation of prolactin secretion and the efficacy of dopamine agonists in the therapy of prolactinomas are well established. The current challenges in management of prolactinomas are related to follow-up after successful therapy. Issues and questions to be addressed in this approach to long-term management of prolactinomas include the frequency of radiographic monitoring, effect of pregnancy and menopause, safety of estrogen in women taking oral contraceptives, and the potential for discontinuation of dopamine agonist therapy.

  13. Human Behaviour in Long-Term Missions

    NASA Technical Reports Server (NTRS)

    1997-01-01

    In this session, Session WP1, the discussion focuses on the following topics: Psychological Support for International Space Station Mission; Psycho-social Training for Man in Space; Study of the Physiological Adaptation of the Crew During A 135-Day Space Simulation; Interpersonal Relationships in Space Simulation, The Long-Term Bed Rest in Head-Down Tilt Position; Psychological Adaptation in Groups of Varying Sizes and Environments; Deviance Among Expeditioners, Defining the Off-Nominal Act in Space and Polar Field Analogs; Getting Effective Sleep in the Space-Station Environment; Human Sleep and Circadian Rhythms are Altered During Spaceflight; and Methodological Approach to Study of Cosmonauts Errors and Its Instrumental Support.

  14. Long-Term Wind Power Variability

    SciTech Connect

    Wan, Y. H.

    2012-01-01

    The National Renewable Energy Laboratory started collecting wind power data from large commercial wind power plants (WPPs) in southwest Minnesota with dedicated dataloggers and communication links in the spring of 2000. Over the years, additional WPPs in other areas were added to and removed from the data collection effort. The longest data stream of actual wind plant output is more than 10 years. The resulting data have been used to analyze wind power fluctuations, frequency distribution of changes, the effects of spatial diversity, and wind power ancillary services. This report uses the multi-year wind power data to examine long-term wind power variability.

  15. Transverse dimension and long-term stability.

    PubMed

    Vanarsdall, R L

    1999-09-01

    This article emphasizes the critical importance of the skeletal differential between the width of the maxilla and the width of the mandible. Undiagnosed transverse discrepancy leads to adverse periodontal response, unstable dental camouflage, and less than optimal dentofacial esthetics. Hundreds of adult retreatment patients corrected for significant maxillary transverse deficiency using surgically assisted maxillary expansion (similar to osseous distraction) has produced excellent stability. Eliciting tooth movement for children (orthopedics, lip bumper, Cetlin plate) in all three planes of space by muscles, eruption, and growth, develops the broader arch form (without the mechanical forces of fixed or removable appliances) and has also demonstrated impressive long term stability.

  16. Terminating a long-term clinical trial.

    PubMed

    Klimt, C R; Canner, P L

    1979-05-01

    Long-term trials often include more than one active treatment group. These may be discontinued independently if found ineffective or possibly harmful. Certain subgroups of patients may be discovered, in the course of a clinical trial, who do not respond satisfactorily and are, therefore, excluded during the course of a trial. Yet anouther kind of termination comes when we have a therapeutic breakthrough or when hope has to be abandoned for demonstrating beneficial effects for one, several, or all treatments included in a trial. Examples from the authors' experience are presented, as are successful and unsuccessful techniques in managing terminations of various types.

  17. Terminating a long-term clinical trial.

    PubMed

    Klimt, C R

    1981-05-01

    Long-term clinical trials often include more than one active treatment group. These may be discontinued independently if found to be ineffective or possibly harmful. Certain subgroups of patients may be discovered, in the course of a clinical trial, who do not respond satisfactorily and are, therefore, excluded during the course of a trial. Yet another kind of termination comes when we have a therapeutic breakthrough or when hope has to be abandoned for demonstrating beneficial effects for one, several, or all treatments included in a trial. Examples from the authors' experience are presented, as are successful and unsuccessful techniques in managing terminations of various types.

  18. A long-term climatology of medicanes

    NASA Astrophysics Data System (ADS)

    Cavicchia, Leone; von Storch, Hans; Gualdi, Silvio

    2014-09-01

    Medicanes, intense and destructive mesoscale cyclones exhibiting several similarities with tropical hurricanes, are known to struck occasionally the Mediterranean Sea. Thanks to a high-resolution dynamical downscaling effort, we are able to study for the first time the long-term climatology of those rare storms in a systematic way. The distribution of medicanes frequency in space and time is discussed, and the environmental factors responsible for their formation are investigated. We find that medicanes develop in those areas of the Mediterranean region where intrusions of cold air in the upper troposphere can produce configurations of thermodynamical disequilibrium of the atmosphere similar to those associated with the formation of tropical cyclones.

  19. Performance considerations in long-term spaceflight

    NASA Technical Reports Server (NTRS)

    Akins, F. R.

    1979-01-01

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

  20. Long-term movement patterns of a coral reef predator

    NASA Astrophysics Data System (ADS)

    Heupel, M. R.; Simpfendorfer, C. A.

    2015-06-01

    Long-term monitoring is required to fully define periodicity and patterns in animal movement. This is particularly relevant for defining what factors are driving the presence, location, and movements of individuals. The long-term movement and space use patterns of grey reef sharks, Carcharhinus amblyrhynchos, were examined on a whole of reef scale in the southern Great Barrier Reef to define whether movement and activity space varied through time. Twenty-nine C. amblyrhynchos were tracked for over 2 years to define movement patterns. All individuals showed high residency within the study site, but also had high roaming indices. This indicated that individuals remained in the region and used all of the monitored habitat (i.e., the entire reef perimeter). Use of space was consistent through time with high reuse of areas most of the year. Therefore, individuals maintained discrete home ranges, but undertook broader movements around the reef at times. Mature males showed greatest variation in movement with larger activity spaces and movement into new regions during the mating season (August-September). Depth use patterns also differed, suggesting behaviour or resource requirements varied between sexes. Examination of the long-term, reef-scale movements of C. amblyrhynchos has revealed that reproductive activity may play a key role in space use and activity patterns. It was unclear whether mating behaviour or an increased need for food to sustain reproductive activity and development played a greater role in these patterns. Reef shark movement patterns are becoming more clearly defined, but research is still required to fully understand the biological drivers for the observed patterns.

  1. The Effects of L2C Signal Tracking on High-Precision Carrier Phase GPS Positioning: Implications for the Next Generation of GNSS Systems

    NASA Astrophysics Data System (ADS)

    Blume, F.; Berglund, H.; Estey, L.

    2012-12-01

    In December 2005, the L2C signal was introduced to improve the accuracy, tracking and redundancy of the GPS system for civilian users. The L2C signal also provides improved SNR data when compared with the L2P(Y) legacy signal. However, GNSS network operators have been hesitant to use the new signal as it is not well determined how positions derived from L2 carrier phase measurements are affected. L2C carrier phase is in quadrature with L2P(Y); some manufacturers correct for this when logging L2C phase while others do not. In cases where both L2C and L2P(Y) are logged simultaneously, translation software must be used carefully in order to select which phase is used in positioning. Modifications were made to UNAVCO's teqc pre-processing software to eliminate confusion, however GNSS networks such as the IGS still suffer occasional data loss due to improperly configured GPS receivers or data flow routines. To date L2C analyses have been restricted to special applications such as snow depth and soil moisture using SNR data, as some high-precision data analysis packages are not compatible with L2C. We use several different methods to determine the effect that tracking and logging L2C has on carrier phase measurements and positioning for various receiver models and configurations. Twenty-four hour zero-length baseline solutions using L2 show sub- millimeter differences in mean positions for both horizontal and vertical components. Direct comparisons of the L2 phase observable from RINEX files with and without the L2C observable show sub-millicycle differences. The magnitude of the variations increased at low elevations. The behavior of the L2P(Y) phase observations or positions from a given receiver were not affected by the enabling of L2C tracking. We find that the use of the L2C-derived carrier phase in real-time applications can be disastrous in cases where receiver brands are mixed between those that correct for quadrature and those that do not (Figure 1). Until

  2. Long-Term Care Policy: Singapore's Experience.

    PubMed

    Chin, Chee Wei Winston; Phua, Kai-Hong

    2016-01-01

    Singapore, like many developed countries, is facing the challenge of a rapidly aging population and the increasing need to provide long-term care (LTC) services for elderly in the community. The Singapore government's philosophy on care for the elderly is that the family should be the first line of support, and it has relied on voluntary welfare organizations (VWOs) or charities for the bulk of LTC service provision. For LTC financing, it has emphasized the principles of co-payment and targeting of state support to the low-income population through means-tested government subsidies. It has also instituted ElderShield, a national severe disability insurance scheme. This paper discusses some of the challenges facing LTC policy in Singapore, particularly the presence of perverse financial incentives for hospitalization, the pitfalls of over-reliance on VWOs, and the challenges facing informal family caregivers. It discusses the role of private LTC insurance in LTC financing, bearing in mind demand- and supply-side failures that have plagued the private LTC insurance market. It suggests the need for more standardized needs assessment and portable LTC benefits, with reference to the Japanese Long-Term Care Insurance program, and also discusses the need to provide more support to informal family caregivers.

  3. Sleep facilitates long-term face adaptation

    PubMed Central

    Ditye, Thomas; Javadi, Amir Homayoun; Carbon, Claus-Christian; Walsh, Vincent

    2013-01-01

    Adaptation is an automatic neural mechanism supporting the optimization of visual processing on the basis of previous experiences. While the short-term effects of adaptation on behaviour and physiology have been studied extensively, perceptual long-term changes associated with adaptation are still poorly understood. Here, we show that the integration of adaptation-dependent long-term shifts in neural function is facilitated by sleep. Perceptual shifts induced by adaptation to a distorted image of a famous person were larger in a group of participants who had slept (experiment 1) or merely napped for 90 min (experiment 2) during the interval between adaptation and test compared with controls who stayed awake. Participants' individual rapid eye movement sleep duration predicted the size of post-sleep behavioural adaptation effects. Our data suggest that sleep prevented decay of adaptation in a way that is qualitatively different from the effects of reduced visual interference known as ‘storage’. In the light of the well-established link between sleep and memory consolidation, our findings link the perceptual mechanisms of sensory adaptation—which are usually not considered to play a relevant role in mnemonic processes—with learning and memory, and at the same time reveal a new function of sleep in cognition. PMID:23986109

  4. Craniopharyngioma in Children: Long-term Outcomes

    PubMed Central

    STEINBOK, Paul

    2015-01-01

    The survival rate for childhood craniopharyngioma has been improving, with more long-term survivors. Unfortunately it is rare for the patient to be normal, either from the disease itself or from the effects of treatment. Long-term survivors of childhood craniopharyngioma suffer a number of impairments, which include visual loss, endocrinopathy, hypothalamic dysfunction, cerebrovascular problems, neurologic and neurocognitive dysfunction. Pituitary insufficiency is present in almost 100%. Visual and hypothalamic dysfunction is common. There is a high risk of metabolic syndrome and increased risk of cerebrovascular disease, including stroke and Moyamoya syndrome. Cognitive, psychosocial, and emotional problems are prevalent. Finally, there is a higher risk of premature death among survivors of craniopharyngioma, and often this is not from tumor recurrence. It is important to consider craniopharyngioma as a chronic disease. There is no perfect treatment. The treatment has to be tailored to the individual patient to minimize dysfunction caused by tumor and treatments. So “cure” of the tumor does not mean a normal patient. The management of the patient and family needs multidisciplinary evaluation and should involve ophthalmology, endocrinology, neurosurgery, oncology, and psychology. Furthermore, it is also important to address emotional issues and social integration. PMID:26345668

  5. Long-term Trend of Sunspot Numbers

    NASA Astrophysics Data System (ADS)

    Gao, P. X.

    2016-10-01

    Using the Hilbert-Huang Transform method, we investigate the long-term trend of yearly mean total sunspot numbers in the time interval of 1700-2015, which come from the World Data Center—the sunspot Index and long-term solar observations. The main findings of this study are summarized below. (1) From the adaptive trend, which is extracted from the yearly mean total sunspot numbers, we can find that the value gradually increases during the time period 1700-1975, then decreases gradually from 1975 to 2015. (2) The Centennial Gleissberg Cycle is extracted from the yearly mean total sunspot numbers and confirms that a new grand minimum is in progress; the Dalton Minimum, the Gleissberg Minimum, and low level of solar activity during solar cycle 24 (the part of the new grand minimum) all can be understood as minima of the Centennial Gleissberg Cycle. (3) Based on the adaptive (overall) trend, and the 100-year and longer timescale trend of yearly mean total sunspot numbers, we can infer that the level of solar activity during the new grand minimum may be close to that during the Gleissberg Minimum, slightly higher than that during the Dalton Minimum, and significantly higher than that during the Maunder Minimum. Our results do not support the suggestion that a new grand minimum, somewhat resembling the Maunder Minimum, is in progress.

  6. Sleep facilitates long-term face adaptation.

    PubMed

    Ditye, Thomas; Javadi, Amir Homayoun; Carbon, Claus-Christian; Walsh, Vincent

    2013-10-22

    Adaptation is an automatic neural mechanism supporting the optimization of visual processing on the basis of previous experiences. While the short-term effects of adaptation on behaviour and physiology have been studied extensively, perceptual long-term changes associated with adaptation are still poorly understood. Here, we show that the integration of adaptation-dependent long-term shifts in neural function is facilitated by sleep. Perceptual shifts induced by adaptation to a distorted image of a famous person were larger in a group of participants who had slept (experiment 1) or merely napped for 90 min (experiment 2) during the interval between adaptation and test compared with controls who stayed awake. Participants' individual rapid eye movement sleep duration predicted the size of post-sleep behavioural adaptation effects. Our data suggest that sleep prevented decay of adaptation in a way that is qualitatively different from the effects of reduced visual interference known as 'storage'. In the light of the well-established link between sleep and memory consolidation, our findings link the perceptual mechanisms of sensory adaptation--which are usually not considered to play a relevant role in mnemonic processes--with learning and memory, and at the same time reveal a new function of sleep in cognition.

  7. Clinical review: Long-term noninvasive ventilation

    PubMed Central

    Robert, Dominique; Argaud, Laurent

    2007-01-01

    Noninvasive positive ventilation has undergone a remarkable evolution over the past decades and is assuming an important role in the management of both acute and chronic respiratory failure. Long-term ventilatory support should be considered a standard of care to treat selected patients following an intensive care unit (ICU) stay. In this setting, appropriate use of noninvasive ventilation can be expected to improve patient outcomes, reduce ICU admission, enhance patient comfort, and increase the efficiency of health care resource utilization. Current literature indicates that noninvasive ventilation improves and stabilizes the clinical course of many patients with chronic ventilatory failure. Noninvasive ventilation also permits long-term mechanical ventilation to be an acceptable option for patients who otherwise would not have been treated if tracheostomy were the only alternative. Nevertheless, these results appear to be better in patients with neuromuscular/-parietal disorders than in chronic obstructive pulmonary disease. This clinical review will address the use of noninvasive ventilation (not including continuous positive airway pressure) mainly in diseases responsible for chronic hypoventilation (that is, restrictive disorders, including neuromuscular disease and lung disease) and incidentally in others such as obstructive sleep apnea or problems of central drive. PMID:17419882

  8. Long term changes in the polar vortices

    NASA Astrophysics Data System (ADS)

    Braathen, Geir O.

    2015-04-01

    As the amount of halogens in the stratosphere is slowly declining and the ozone layer slowly recovers it is of interest to see how the meteorological conditions in the vortex develop over the long term since such changes might alter the foreseen ozone recovery. In conjunction with the publication of the WMO Antarctic and Arctic Ozone Bulletins, WMO has acquired the ERA Interim global reanalysis data set for several meteorological parameters. This data set goes from 1979 - present. These long time series of data can be used for several useful studies of the long term development of the polar vortices. Several "environmental indicators" for vortex change have been calculated, and a climatology, as well as trends, for these parameters will be presented. These indicators can act as yardsticks and will be useful for understanding past and future changes in the polar vortices and how these changes affect polar ozone depletion. Examples of indicators are: vortex mean temperature, vortex minimum temperature, vortex mean PV, vortex "importance" (PV*area), vortex break-up time, mean and maximum wind speed. Data for both the north and south polar vortices have been analysed at several isentropic levels from 350 to 850 K. A possible link between changes in PV and sudden stratospheric warmings will be investigated, and the results presented.

  9. Long-term Caspian Sea level change

    NASA Astrophysics Data System (ADS)

    Chen, J. L.; Pekker, T.; Wilson, C. R.; Tapley, B. D.; Kostianoy, A. G.; Cretaux, J.-F.; Safarov, E. S.

    2017-07-01

    Caspian Sea level (CSL) has undergone substantial fluctuations during the past several hundred years. The causes over the entire historical period are uncertain, but we investigate here large changes seen in the past several decades. We use climate model-predicted precipitation (P), evaporation (E), and observed river runoff (R) to reconstruct long-term CSL changes for 1979-2015 and show that PER (P-E + R) flux predictions agree very well with observed CSL changes. The observed rapid CSL increase (about 12.74 cm/yr) and significant drop ( -6.72 cm/yr) during the periods 1979-1995 and 1996-2015 are well accounted for by integrated PER flux predictions of +12.38 and -6.79 cm/yr, respectively. We show that increased evaporation rates over the Caspian Sea play a dominant role in reversing the increasing trend in CSL during the past 37 years. The current long-term decline in CSL is expected to continue into the foreseeable future, under global warming scenarios.

  10. Long term efficacy of a pen injector.

    PubMed

    Dinneen, S F; Cronin, C C; O'Sullivan, D J

    1991-09-01

    We assessed the long term efficacy of Novopen as a form of insulin administration. Records were obtained on 48 patients who were treated with Novopen between January '86 and October '88. Six patients were excluded due to insufficient data. The study group of 42 patients comprised 22 females and 20 males of average age 33 years (range 17-66). Mean Hb.A1 rose from 10.6% to 12.1% after Novopen therapy, a rise of 14.1%. This rise is both clinically and statistically significant (p less than 0.001; 99% confidence limits 0.59-2.78). Increases in weight and insulin dose were also noted, but did not reach statistical significance. The majority of patients felt Novopen was superior to twice daily insulin in terms of ease of administration (81%) and flexibility of lifestyle (95%), and all who were using Novopen wished to continue with it. More than 50% of patients admitted to altering their dietary habits while using Novopen. Despite continuing patient satisfaction with this form of insulin administration, its long-term use may be associated with sub-optimal metabolic control.

  11. Climate Predictability and Long Term Memory

    NASA Astrophysics Data System (ADS)

    Zhu, X.; Blender, R.; Fraedrich, K.; Liu, Z.

    2010-09-01

    The benefit of climate Long Term Memory (LTM) for long term prediction is assessed using data from a millennium control simulation with the atmosphere ocean general circulation model ECHAM5/MPIOM. The forecast skills are evaluated for surface temperature time series at individual grid points. LTM is characterised by the Hurst exponent in the power-law scaling of the fluctuation function which is determined by detrended fluctuation analysis (DFA). LTM with a Hurst exponent close to 0.9 occurs mainly in high latitude oceans, which are also characterized by high potential predictability. Climate predictability is diagnosed in terms of potentially predictable variance fractions. Explicit prediction experiments for various time steps are conducted on a grid point basis using an auto-correlation (AR1) predictor: in regions with LTM, prediction skills are beyond that expected from red noise persistence; exceptions occur in some areas in the southern oceans and over the northern hemisphere continents. Extending the predictability analysis to the fully forced simulation shows large improvement in prediction skills.

  12. Long-term phenotypic evolution of bacteria.

    PubMed

    Plata, Germán; Henry, Christopher S; Vitkup, Dennis

    2015-01-15

    For many decades comparative analyses of protein sequences and structures have been used to investigate fundamental principles of molecular evolution. In contrast, relatively little is known about the long-term evolution of species' phenotypic and genetic properties. This represents an important gap in our understanding of evolution, as exactly these proprieties play key roles in natural selection and adaptation to diverse environments. Here we perform a comparative analysis of bacterial growth and gene deletion phenotypes using hundreds of genome-scale metabolic models. Overall, bacterial phenotypic evolution can be described by a two-stage process with a rapid initial phenotypic diversification followed by a slow long-term exponential divergence. The observed average divergence trend, with approximately similar fractions of phenotypic properties changing per unit time, continues for billions of years. We experimentally confirm the predicted divergence trend using the phenotypic profiles of 40 diverse bacterial species across more than 60 growth conditions. Our analysis suggests that, at long evolutionary distances, gene essentiality is significantly more conserved than the ability to utilize different nutrients, while synthetic lethality is significantly less conserved. We also find that although a rapid phenotypic evolution is sometimes observed within the same species, a transition from high to low phenotypic similarity occurs primarily at the genus level.

  13. Long term perfusion system supporting adipogenesis

    PubMed Central

    Abbott, Rosalyn D.; Raja, Waseem K.; Wang, Rebecca Y.; Stinson, Jordan A.; Glettig, Dean L.; Burke, Kelly A.; Kaplan, David L.

    2015-01-01

    Adipose tissue engineered models are needed to enhance our understanding of disease mechanisms and for soft tissue regenerative strategies. Perfusion systems generate more physiologically relevant and sustainable adipose tissue models, however adipocytes have unique properties that make culturing them in a perfusion environment challenging. In this paper we describe the methods involved in the development of two perfusion culture systems (2D and 3D) to test their applicability for long term in vitro adipogenic cultures. It was hypothesized that a silk protein biomaterial scaffold would provide a 3D framework, in combination with perfusion flow, to generate a more physiologically relevant sustainable adipose tissue engineered model than 2D cell culture. Consistent with other studies evaluating 2D and 3D culture systems for adipogenesis we found that both systems successfully model adipogensis, however 3D culture systems were more robust, providing the mechanical structure required to contain the large, fragile adipocytes that were lost in 2D perfused culture systems. 3D perfusion also stimulated greater lipogenesis and lipolysis and resulted in decreased secretion of LDH compared to 2D perfusion. Regardless of culture configuration (2D or 3D) greater glycerol was secreted with the increased nutritional supply provided by perfusion of fresh media. These results are promising for adipose tissue engineering applications including long term cultures for studying disease mechanisms and regenerative approaches, where both acute (days to weeks) and chronic (weeks to months) cultivation are critical for useful insight. PMID:25843606

  14. Long-term experience with indapamide.

    PubMed

    Beling, S; Vukovich, R A; Neiss, E S; Zisblatt, M; Webb, E; Losi, M

    1983-07-01

    Indapamide, 2.5 mg administered once daily for periods up to 36 months, was found to be safe and effective for the long-term control of mild to moderate hypertension. The effects of hydrochlorothiazide, 50 mg, and indapamide, 2.5 mg, were studied in two randomized, double-blind, multicenter trials. Data from the two multicenter trials (20 study sites) were pooled for purposes of comparison. Significant reductions in systolic and diastolic blood pressure, with patients in both supine and standing positions, occurred in both groups within the first 8 weeks of treatment. This effect was maintained throughout the active treatment period. Success, as determined by the therapeutic success rate (percentage of patients with decreases of standing phase V diastolic blood pressure of at least 10 mm Hg or to below 90 mm Hg), occurred in 53% of the patients given hydrochlorothiazide and in 56% of the indapamide-treated patients. During the study period, the nature, frequency, and severity of adverse reactions were similar for both groups. There was no clinically significant difference between the treatment groups for the laboratory assessments. Patients who completed the multicenter trials were eligible for participation in an ongoing long-term extension study of the safety of indapamide. Data are available for periods up to 36 months and demonstrate neither augmentation of clinical or laboratory adverse effects nor any potentially harmful indicators that could be attributed to prolonged treatment.

  15. Long Term Changes in the Polar Vortices

    NASA Astrophysics Data System (ADS)

    Braathen, Geir O.

    2016-04-01

    As the amount of halogens in the stratosphere is slowly declining and the ozone layer slowly recovers it is of interest to see how the meteorological conditions in the vortex develop over the long term since such changes might alter the foreseen ozone recovery. In conjunction with the publication of the WMO Antarctic and Arctic Ozone Bulletins, WMO has acquired the ERA Interim global reanalysis data set for several meteorological parameters. This data set goes from 1979 - present. These long time series of data can be used for several useful studies of the long term development of the polar vortices. Several "environmental indicators" for vortex change have been calculated, and a climatology, as well as trends, for these parameters will be presented. These indicators can act as yardsticks and will be useful for understanding past and future changes in the polar vortices and how these changes affect polar ozone depletion. Examples of indicators are: vortex mean temperature, vortex minimum temperature, vortex mean PV, vortex "importance" (PV*area), vortex break-up time, mean and maximum wind speed. Data for both the north and south polar vortices have been analysed at several isentropic levels from 350 to 850 K. A possible link between changes in PV and sudden stratospheric warmings will be investigated, and the results presented. The unusual meteorological conditions of the 2015 south polar vortex and the 2010/11 and 2015/16 north polar vortices will be compared to other recent years.

  16. Long term effects of Escherichia coli mastitis.

    PubMed

    Blum, Shlomo E; Heller, Elimelech D; Leitner, Gabriel

    2014-07-01

    Escherichia coli is one of the most frequently diagnosed causes of bovine mastitis, and is typically associated with acute, clinical mastitis. The objective of the present study was to evaluate the long term effects of intramammary infections by E. coli on milk yield and quality, especially milk coagulation. Twenty-four Israeli Holstein cows diagnosed with clinical mastitis due to intramammary infection by E. coli were used in this study. Mean lactation number, days in milk (DIM) and daily milk yield (DMY) at the time of infection was 3.3 ± 1.3, 131.7 days ± 78.6 and 45.7 L ± 8.4, respectively. DMY, milk constituents, somatic cells count (SCC), differential leukocytes count and coagulation parameters were subsequently assessed. Two patterns of inflammation were identified: 'short inflammation', characterized by <15% decrease in DMY and <30 days until return to normal (n = 5), and 'long inflammation', characterized by >15% decrease in DMY and >30 days to reach a new maximum DMY (n = 19). The estimated mean loss of marketable milk during the study was 200 L/cow for 'short inflammation' cases, and 1,500 L/cow for 'long inflammation' ones. Significant differences between 'short' and 'long inflammation' effects were found in almost all parameters studied. Long-term detrimental effects on milk quality were found regardless of clinical or bacteriological cure of affected glands.

  17. GPS navigation experiment using high precision GPS timing receivers

    NASA Technical Reports Server (NTRS)

    Buisson, J. A.; Oaks, O. J.; Lister, M. J.; Wardrip, S. C.; Leschiutta, S.; Galliano, P. G.; Cordara, D.; Pettiti, V.; Detoma, E.; Dachel, P.

    1985-01-01

    Global Positioning System (GPS) Time Transfer receivers were developed by the Naval Research Laboratory (NRL) to provide synchronization for the NASA Global Laser Tracking Network (GLTN). The capabilities of the receiver are being expanded mainly through software modification to: Demonstrate the position location capabilities of a single channel receiver unsign the GPS C/A code; and Demonstrate the time/navigation capability of the receiver onboard a moving platform, by sequential tracking of GPS satellites.

  18. Short- and Long-Term Propagation of Spacecraft Orbits

    NASA Technical Reports Server (NTRS)

    Smith, John C., Jr.; Sweetser, Theodore; Chung, Min-Kun; Yen, Chen-Wan L.; Roncoli, Ralph B.; Kwok, Johnny H.; Vincent, Mark A.

    2008-01-01

    The Planetary Observer Planning Software (POPS) comprises four computer programs for use in designing orbits of spacecraft about planets. These programs are the Planetary Observer High Precision Orbit Propagator (POHOP), the Planetary Observer Long-Term Orbit Predictor (POLOP), the Planetary Observer Post Processor (POPP), and the Planetary Observer Plotting (POPLOT) program. POHOP and POLOP integrate the equations of motion to propagate an initial set of classical orbit elements to a future epoch. POHOP models shortterm (one revolution) orbital motion; POLOP averages out the short-term behavior but requires far less processing time than do older programs that perform long-term orbit propagations. POPP postprocesses the spacecraft ephemeris created by POHOP or POLOP (or optionally can use a less accurate internal ephemeris) to search for trajectory-related geometric events including, for example, rising or setting of a spacecraft as observed from a ground site. For each such event, POPP puts out such user-specified data as the time, elevation, and azimuth. POPLOT is a graphics program that plots data generated by POPP. POPLOT can plot orbit ground tracks on a world map and can produce a variety of summaries and generic ordinate-vs.-abscissa plots of any POPP data.

  19. Procedures and applications of long-term intravital microscopy.

    PubMed

    Prunier, Chloé; Chen, Na; Ritsma, Laila; Vrisekoop, Nienke

    2017-09-01

    Intravital microscopy (IVM) is increasingly used in biomedical research to study dynamic processes at cellular and subcellular resolution in their natural environment. Long-term IVM especially can be applied to visualize migration and proliferation over days to months within the same animal without recurrent surgeries. Skin can be repetitively imaged without surgery. To intermittently visualize cells in other organs, such as liver, mammary gland and brain, different imaging windows including the abdominal imaging window (AIW), dermal imaging window (DIW) and cranial imaging window (CIW) have been developed. In this review, we describe the procedure of window implantation and pros and cons of each technique as well as methods to retrace a position of interest over time. In addition, different fluorescent biosensors to facilitate the tracking of cells for different purposes, such as monitoring cell migration and proliferation, are discussed. Finally, we consider new techniques and possibilities of how long-term IVM can be even further improved in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Imaging windows for long-term intravital imaging

    PubMed Central

    Alieva, Maria; Ritsma, Laila; Giedt, Randy J; Weissleder, Ralph; van Rheenen, Jacco

    2014-01-01

    Intravital microscopy is increasingly used to visualize and quantitate dynamic biological processes at the (sub)cellular level in live animals. By visualizing tissues through imaging windows, individual cells (e.g., cancer, host, or stem cells) can be tracked and studied over a time-span of days to months. Several imaging windows have been developed to access tissues including the brain, superficial fascia, mammary glands, liver, kidney, pancreas, and small intestine among others. Here, we review the development of imaging windows and compare the most commonly used long-term imaging windows for cancer biology: the cranial imaging window, the dorsal skin fold chamber, the mammary imaging window, and the abdominal imaging window. Moreover, we provide technical details, considerations, and trouble-shooting tips on the surgical procedures and microscopy setups for each imaging window and explain different strategies to assure imaging of the same area over multiple imaging sessions. This review aims to be a useful resource for establishing the long-term intravital imaging procedure. PMID:28243510

  1. Managing soils for long-term productivity

    PubMed Central

    Syers, J. K.

    1997-01-01

    Meeting the goal of long-term agricultural productivity requires that soil degradation be halted and reversed. Soil fertility decline is a key factor in soil degradation and is probably the major cause of declining crop yields. There is evidence that the contribution of declining soil fertility to soil degradation has been underestimated.
    Sensitivity to soil degradation is implicit in the assessment of the sustainability of land management practices, with wide recognition of the fact that soils vary in their ability to resist change and recover subsequent to stress. The concept of resilience in relation to sustainability requires further elaboration and evaluation.
    In the context of soil degradation, a decline in soil fertility is primarily interpreted as the depletion of organic matter and plant nutrients. Despite a higher turnover rate of organic matter in the tropics there is no intrinsic difference between the organic matter content of soils from tropical and temperate regions. The level of organic matter in a soil is closely related to the above and below ground inputs. In the absence of adequate organic material inputs and where cultivation is continuous, soil organic matter declines progressively. Maintaining the quantity and quality of soil organic matter should be a guiding principle in developing management practices.
    Soil microbial biomass serves as an important reservoir of nitrogen (N), phosphorus (P) and sulphur (S), and regulates the cycling of organic matter and nutrients. Because of its high turnover rate, microbial biomass reacts quickly to changes in management and is a sensitive indicator for monitoring and predicting changes in soil organic matter. Modelling techniques have been reasonably successful in predicting changes in soil organic matter with different organic material inputs, but there is little information from the tropics.
    Nutrient depletion through harvested crop components and residue removal, and by leaching and soil

  2. On "GPS weeknumber rollover".

    NASA Astrophysics Data System (ADS)

    Chen, Hongqing

    1998-12-01

    The relation between GPS system time and weeknumber is introduced, and it is explained that the limited number of (10 bits) used in the GPS navigation message causes the problem of GPS weeknumber rollover which is similar to that the millennium problem will occur when the year number becomes 00 from 99. The GPS weeknumber has the maximum of 1023 so that it will rollover from 1023 to 0 at the midnight of August 21 - 22, 1999. The GPS users should check if the receivers can work correctly once the "rollover" occurs. If the equipments or softwares for the GPS receiver are not perfect. The receiver will interpret the new week 0 as January 6, 1980, and some receivers may display wrong information or wrong locating results, even stop tracking any satellite. The GPS users should contact the manufacturer of the GPS receiver to determine if the GPS receiver will be affected by the GPS weeknumber rollover. It should be noted that the problem of time rollover often occurs for timing service.

  3. Neurotoxicity testing during long-term studies.

    PubMed

    Ivens, I

    1990-01-01

    Several tests and methods for the investigation of neurotoxicity were performed with female Wistar rats for up to 187 days. The methods were validated by testing 10 rats treated with beta,beta'-iminodipropionitrile (IDPN) and 10 control rats. Cage side observation of the animals revealed signs of altered behavior and motor dysfunction of the IDPN-treated rats. Results of a neuromuscular screen indicated changes in gait, righting reflex, grip strength and performance of the negative geotropism test. Investigation of the animals in activity monitors and on the accelerating rotarod showed changes of several parameters. The motor nerve conduction velocity, measured 6 months after the first treatment, was reduced by 6.7 meters per second in the IDPN group compared to controls. From the results of the tests it can be concluded that the methods chosen can be used during long-term studies but may be most useful for animals not older than 12 months.

  4. Long term cryogenic storage facility systems study

    NASA Technical Reports Server (NTRS)

    Schuster, John R.

    1987-01-01

    The Long Term Cryogenic Storage Facility Systems Study (LTCSFSS) is a Phase A study of a large capacity propellant depot for the space based, cryogenic orbital transfer vehicle. The study is being performed for Marshall Space Flight Center by General Dynamics Space Systems Division and has five principal objectives: (1) Definition of preliminary concept designs for four storage facility concepts; (2) Selection of preferred concepts through the application of trade studies to candidate propellant management system components; (3) Preparation of a conceptual design for an orbital storage facility; (4) Development of supporting research and technology requirements; and (5) Development of a test program to demonstrate facility performance. The initial study has been completed, and continuation activities are just getting under way to provide greater detail in key areas and accommodate changes in study guidelines and assumptions.

  5. Reducing long-term reservoir performance uncertainty

    SciTech Connect

    Lippmann, M.J.

    1988-04-01

    Reservoir performance is one of the key issues that have to be addressed before going ahead with the development of a geothermal field. In order to select the type and size of the power plant and design other surface installations, it is necessary to know the characteristics of the production wells and of the produced fluids, and to predict the changes over a 10--30 year period. This is not a straightforward task, as in most cases the calculations have to be made on the basis of data collected before significant fluid volumes have been extracted from the reservoir. The paper describes the methodology used in predicting the long-term performance of hydrothermal systems, as well as DOE/GTD-sponsored research aimed at reducing the uncertainties associated with these predictions. 27 refs., 1 fig.

  6. Long-term monitoring for closed sites

    SciTech Connect

    Golchert, N.W.; Sedlet, J.; Veluri, V.R.

    1985-01-01

    A procedure is presented for planning and implementing a long-term environmental monitoring program for closed low-level radioactive waste disposal sites. The initial task in this procedure is to collect the available information on the legal/regulatory requirements, site and area characteristics, source term, pathway analysis, and prior monitoring results. This information is coupled with parameters such as half-life and retardation factors to develop a monitoring program. As examples, programs are presented for a site that has had little or no waste migration, and for sites where waste has been moved by suface water, by ground water, and by air. Sampling techniques and practices are discussed relative to how a current program would be structured and projections are made on techniques and practices expected to be available in the future. 8 refs., 2 figs.

  7. Emotional behavior in long-term marriage.

    PubMed

    Carstensen, L L; Gottman, J M; Levenson, R W

    1995-03-01

    In exploring the emotional climate of long-term marriages, this study used an observational coding system to identify specific emotional behaviors expressed by middle-aged and older spouses during discussions of a marital problem. One hundred and fifty-six couples differing in age and marital satisfaction were studied. Emotional behaviors expressed by couples differed as a function of age, gender, and marital satisfaction. In older couples, the resolution of conflict was less emotionally negative and more affectionate than in middle-aged marriages. Differences between husbands and wives and between happy and unhappy marriages were also found. Wives were more affectively negative than husbands, whereas husbands were more defensive than wives, and unhappy marriages involved greater exchange of negative affect than happy marriages.

  8. Long Term Hydrological (Radiological) Site Monitoring Data

    EPA Pesticide Factsheets

    Quality Data Asset includes all current and historical data on the quality of water with regard to the presence of water pollutants of all kinds regulated by the Clean Water Act. Under the new Interagency Agreement with the Department of Energy (DOE), the Radiation & Indoor Environments National Laboratory (R&IE), Office of Radiation and Indoor Air (ORIA), EPA, located in Las Vegas, NV, conducts a Long-Term Hydrological Monitoring Program (LTHMP) providing laboratory sampling/analysis and Quality Assurance and Control to measure radioactivity concentrations in the water sources near the sites of former underground nuclear explosions. The results of the LTHMP provide assurance that radioactive material from the tests have not migrated into water supplies.

  9. Long-term U. S. energy outlook

    SciTech Connect

    Friesen, G.

    1984-01-01

    Each year Chase Econometrics offers its clients a brief summary of the assumptions underlying the long-term energy forecast for the U.S. To illustrate the uncertainty involved in forecasting for the period to the year 2000, they choose to compare forecasts with some recent projections prepared by the Department of Energy's Office of Policy, Planning and Analysis for the annual National Energy Policy Plan supplement. Particular emphasis is placed on Scenario B, which is the mid-range reference case. As the introduction to the supplement emphasizes, the NEPP projections should not be considered a statement of the policy goals of the Reagan Administration. They represent an analysis of the possible evolution of U.S. energy markets, given current information and existing policies. The purpose of providing Scenario B as a reference case as well as Scenarios A and C as alternate cases is to show the sensitivity of oil price projections to small swings in energy demand.

  10. Advanced long term cryogenic storage systems

    NASA Technical Reports Server (NTRS)

    Brown, Norman S.

    1987-01-01

    Long term, cryogenic fluid storage facilities will be required to support future space programs such as the space-based Orbital Transfer Vehicle (OTV), Telescopes, and Laser Systems. An orbital liquid oxygen/liquid hydrogen storage system with an initial capacity of approximately 200,000 lb will be required. The storage facility tank design must have the capability of fluid acquisition in microgravity and limit cryogen boiloff due to environmental heating. Cryogenic boiloff management features, minimizing Earth-to-orbit transportation costs, will include advanced thick multilayer insulation/integrated vapor cooled shield concepts, low conductance support structures, and refrigeration/reliquefaction systems. Contracted study efforts are under way to develop storage system designs, technology plans, test article hardware designs, and develop plans for ground/flight testing.

  11. Withdrawal from long-term benzodiazepine treatment.

    PubMed Central

    Petursson, H; Lader, M H

    1981-01-01

    Long-term, normal-dose benzodiazepine treatment was discontinued in 16 patients who were suspected of being dependent on their medication. The withdrawal was gradual, placebo-controlled, and double-blind. All the patients experienced some form of withdrawal reaction, which ranged from anxiety and dysphoria to moderate affective and perceptual changes. Symptom ratings rose as the drugs were discontinued, but usually subsided to prewithdrawal levels over the next two to four weeks. Other features of the withdrawal included disturbance of sleep and appetite and noticeable weight loss. Electroencephalography showed appreciable reduction in fast-wave activity as the drugs were withdrawn, and an improvement in psychological performance was recorded by the Digit Symbol Substitution Test. Because of the risk of dependence on benzodiazepines these agents should probably not be given as regular daily treatment for chronic anxiety. PMID:6114776

  12. [Enteral nutrition through long-term jejunostomy].

    PubMed

    Fernández, T; Neira, P; Enríquez, C

    2008-01-01

    We present the case of a female patient suffering a peritonitis episode after subtotal gastrectomy due to gastric neoplasm in relation to lesser curvature necrosis extending to the anterior esophageal wall. This an uncommon andsevere complication that made mandatory further aggressive surgery: transection of the abdominal esophagus, transection of the gastric stump, and cervical esophagostomy with creation of a jejunostomy with a needle catheter for feeding. This digestive tube access technique is generally used during major abdominal post-surgery until oral intake is reestablished. Our patient has been 187 days with this therapy since reconstruction of the GI tract was ruled out due to tumoral infiltration of the colon and tumor recurrence at the gastrohepatic omentum. To date, there has been no complication from permanence and/or long-term use of this technique.

  13. [Childhood liver transplantation. Long-term results].

    PubMed

    Jara, Paloma; Hierro, Loreto

    2010-05-01

    Liver transplantation allows long-term survival (10 years or more) in 75% of children receiving transplants before 2000. The risk of mortality after the first year is 4-10% in the next 10-20 years. Chronic rejection affects 6%. The need for late retransplantation is 3-5%. However, the follow-up of these patients involves the management of diverse problems in the graft (immunological, biliary, vascular) and others related to the use of immunosuppressants (renal dysfunction, lymphoproliferative syndrome). The transition from pediatric to adult care generates special needs. Adolescence and young adulthood are associated with a lack of compliance. Adult specialists should be aware of the special features of the original diagnosis and the surgical techniques used in childhood transplantation. Final quality of life is good overall but is lower than that in healthy young persons.

  14. Long-term leaching of photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Nover, Jessica; Zapf-Gottwick, Renate; Feifel, Carolin; Koch, Michael; Metzger, Jörg W.; Werner, Jürgen H.

    2017-08-01

    Some photovoltaic module technologies use toxic materials. We report long-term leaching on photovoltaic module pieces of 5 × 5 cm2 size. The pieces are cut out from modules of the four major commercial photovoltaic technologies: crystalline and amorphous silicon, cadmium telluride as well as from copper indium gallium diselenide. To simulate different environmental conditions, leaching occurs at room temperature in three different water-based solutions with pH 3, 7, and 11. No agitation is performed to simulate more representative field conditions. After 360 days, about 1.4% of lead from crystalline silicon module pieces and 62% of cadmium from cadmium telluride module pieces are leached out in acidic solutions. The leaching depends heavily on the pH and the redox potential of the aqueous solutions and it increases with time. The leaching behavior is predictable by thermodynamic stability considerations. These predictions are in good agreement with the experimental results.

  15. Technology for long-term care.

    PubMed

    Tak, Sunghee H; Benefield, Lazelle E; Mahoney, Diane Feeney

    2010-01-01

    Severe staff shortages in long-term care (LTC) make it difficult to meet the demands of the growing aging population. Further, technology-savvy Baby Boomers are expected to reshape the current institutional environments toward gaining more freedom and control in their care and lives. Voices from business, academia, research, advocacy organizations, and government bodies suggest that innovative technological approaches are the linchpin that may prepare society to cope with these projected demands. In this article, we review the current state of aging-related technology, identify potential areas for efficacy testing on improving the quality of life of LTC residents in future research, and discuss barriers to implementation of LTC technology. Finally, we present a vision of future technology use that could transform current care practices.

  16. Radiation risk during long-term spaceflight.

    PubMed

    Petrov, V M

    2002-01-01

    Cosmonauts' exposure to cosmic rays during long-term spaceflight can cause unfavorable effects in health and risk for the crew members' lives. All unfavorable effects induced by exposure should be taken into consideration for the risk estimation. They should include both the acute deterministic effects and delayed effects called stochastic. On the ground the limitation of unfavorable consequences of acute exposure is achieved by means of establishing dose limits. But in space applications this approach can't be acceptable. Establishing a fixed dose limit is adequate to introducing indefinite reserve coefficient and therefore ineffective usage of spacecraft resource. The method of radiation risk calculation caused by acute and delayed effects of cosmonauts' exposure is discussed and substantiated in the report. Peculiarities of the impact of permanent radiation sources (galactic cosmic rays and trapped radiation) and the variable one (solar cosmic rays) are taken into consideration. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  17. Long-term control of root growth

    SciTech Connect

    Burton, F.G.; Cataldo, D.A.; Cline, J.F.; Skiens, W.E.

    1992-05-26

    A method and system for long-term control of root growth without killing the plants bearing those roots involves incorporating a 2,6-dinitroaniline in a polymer and disposing the polymer in an area in which root control is desired. This results in controlled release of the substituted aniline herbicide over a period of many years. Herbicides of this class have the property of preventing root elongation without translocating into other parts of the plant. The herbicide may be encapsulated in the polymer or mixed with it. The polymer-herbicide mixture may be formed into pellets, sheets, pipe gaskets, pipes for carrying water, or various other forms. The invention may be applied to other protection of buried hazardous wastes, protection of underground pipes, prevention of root intrusion beneath slabs, the dwarfing of trees or shrubs and other applications. The preferred herbicide is 4-difluoromethyl-N,N-dipropyl-2,6-dinitro-aniline, commonly known as trifluralin. 7 figs.

  18. Long-term control of root growth

    DOEpatents

    Burton, Frederick G.; Cataldo, Dominic A.; Cline, John F.; Skiens, W. Eugene

    1992-05-26

    A method and system for long-term control of root growth without killing the plants bearing those roots involves incorporating a 2,6-dinitroaniline in a polymer and disposing the polymer in an area in which root control is desired. This results in controlled release of the substituted aniline herbicide over a period of many years. Herbicides of this class have the property of preventing root elongation without translocating into other parts of the plant. The herbicide may be encapsulated in the polymer or mixed with it. The polymer-herbicide mixture may be formed into pellets, sheets, pipe gaskets, pipes for carrying water, or various other forms. The invention may be applied to other protection of buried hazardous wastes, protection of underground pipes, prevention of root intrusion beneath slabs, the dwarfing of trees or shrubs and other applications. The preferred herbicide is 4-difluoromethyl-N,N-dipropyl-2,6-dinitro-aniline, commonly known as trifluralin.

  19. Long-term dynamics of Typha populations

    USGS Publications Warehouse

    Grace, J.B.; Wetzel, R.G.

    1998-01-01

    The zonation of Typha populations in an experimental pond in Michigan was re-examined 15 years after the original sampling to gain insight into the long-term dynamics. Current distributions of Typha populations were also examined in additional experimental ponds at the site that have been maintained for 23 years. The zonation between T. latifolia and T. angustifolia in the previously studied pond 15 years after the initial sampling revealed that the density and distribution of shoots had not changed significantly. Thus, it appears that previously reported results (based on 7- year old populations) have remained consistent over time. Additional insight into the interaction between these two taxa was sought by comparing mixed and monoculture stands in five experimental ponds that have remained undisturbed for their 23-year history. The maximum depth of T. latifolia, the shallow- water species, was not significantly reduced when growing in the presence of the more flood tolerant T. angustifolia. In contrast, the minimum depth of T. angustifolia was reduced from 0 to 37 cm when in the presence of T. latifolia. When total populations were compared between monoculture and mixed stands, the average density of T. angustifolia shoots was 59.4 percent lower in mixed stands while the density of T. latifolia was 32 percent lower, with T. angustifolia most affected at shallow depths (reduced by 92 percent) and T. latifolia most affected at the deepest depths (reduced by 60 percent). These long-term observations indicate that competitive displacement between Typha taxa has remained stable over time.

  20. Reconstructing the long-term aa index

    NASA Astrophysics Data System (ADS)

    Clilverd, Mark A.; Clarke, Ellen; Ulich, Thomas; Linthe, Joachim; Rishbeth, Henry

    2005-07-01

    The robustness of the aa geomagnetic index is of critical importance to the debate about the previously reported doubling of the solar coronal magnetic field in the last 100 years, inferred from an increasing trend in this index. To test the trend in aa, we have reconstructed the aa index using two long-running European stations (Sodankylä from 1914 and Niemegk from 1890) to provide data for the northern component of the index that are independent of data from the UK observatories used in the "official" aa index. Both the fully "reconstructed" aa series, based on Sodankylä (67°N, L = 5.2 RE) and Niemegk (52°N, L = 2.3 RE) data in combination with the official aa Southern Hemisphere data, confirm the increasing trend in the index. The Niemegk-based index shows little solar cycle variation in its deviation from the official index, probably because of the midlatitude location of the station. The high-latitude station, Sodankylä, is more affected by active geomagnetic conditions during solar maximum because of the proximity of the auroral oval to the station. Nevertheless, its index also clearly confirms the increasing trend in the aa index and hence supports the idea of a long-term increase in solar coronal magnetic field strength. As an added test, we reconstructed the aa index from a single site using data from two long-running UK stations, Eskdalemuir and Lerwick, applying a technique known as interhourly variation (IHV) proposed by Svalgaard et al. (2004). The resulting series is designed to be primarily sensitive to solar wind conditions. Both the reconstructed aaIHV also showed an increasing trend with time and high consistency with the official aa index. Overall, we conclude that the robustness of the trend in the aa index supports the idea of a long-term increase in solar coronal magnetic field strength.

  1. Posterior urethral valves: long-term outcome.

    PubMed

    Caione, Paolo; Nappo, Simona Gerocarni

    2011-10-01

    Posterior urethral valves represent the most common cause of bladder outlet obstruction in infancy that impairs renal and bladder function. Long-term outcome of patients with previous PUV is evaluated. Patients over 18 years of age, treated from 1982 to 1995 before the age of 3 years were considered. Previous surgery, renal function, bladder activity, urinary incontinence, and fertility/sexual activity were evaluated. Clinical interview, creatinine clearance, uroflowmetry with ultrasound post-void urine residue, and self-administered questionnaire were recorded. Out of 45 identified records, 24 patients (53.3%) accepted to be enrolled (age 18-34 years, mean 23 years). The mean follow-up was 19.5 years (16-30 years). Out of the 21 excluded patients, 20 did not reply to the clinical interview and 1 died at age of 6 years. All the 24 patients had early endoscopic section of PUV; nine also received transient ureterocutaneostomy or vesicostomy. Ureteroneocystostomy was performed in five patients and ureterocystoplasty with unilateral nephrectomy in two. At follow-up chronic renal failure was detected in 13 patients (54.1%) and 9 (37.5%) had arterial hypertension. End-stage renal disease developed in five patients (20.8%): three had successful renal transplantation and two were in dialysis. Lower urinary tract symptoms were present in seven patients (29.1%). No significant fertility deficit and sexual dysfunction were observed in 23 patients, while 1 patient was azoospermic. No paternity was reported so far. Long-term outcome of patients with previously treated PUV is mandatory. Kidney, bladder, and sexual functions should be monitored till adulthood to verify any modified behaviour.

  2. Long term results of pneumatic retinopexy

    PubMed Central

    Ellakwa, Amin F

    2012-01-01

    Background Rhegmatogenous retinal detachment is a commonly encountered retinal problem where rapid treatment can prevent irreversible vision loss. Pneumatic retinopexy (PR) is a simple, minimally invasive procedure for retinal reattachment. Purpose This study aimed to assess the long-term anatomical and functional outcome of pneumatic retinopexy in primary rhegmatogenous retinal detachment. Patients and methods A prospective interventional study was performed. Subjects with rhegmatogenous retinal detachment who underwent pneumatic retinopexy from May 2006 to May 2007 at Menoufiya University Hospital were included in this study with at least 3 years follow-up. Results A total of 40 cases were included in the study. The mean age of patients was 44.25 ± 10.85 years. Reattachment of the retina was achieved in 100% of cases. In 75% of cases, the primary intervention was successful. However, the retina redetached in 20% of these during the first 6 months, requiring reinjection or another procedure. Three years after the first intervention, follow-up measurement of the mean visual acuity of the eyes without reoperation was 0.40 ± 0.21 while the mean visual acuity of the eyes which needed additional operations was 0.22 ± 0.13. Conclusion Sixty percent of the cases obtained long-term retinal reattachment with a single operation success (SOS), with good visual recovery and less morbidity than other more invasive procedures like scleral buckling or pars plana vitrectomy, translating to higher productivity for the patient. This procedure, being quicker than the alternatives, also saves the surgeon’s time, making PR a good choice for managing primary rhegmatogenous retinal detachment in developing countries. PMID:22275808

  3. Managing Records for the Long Term - 12363

    SciTech Connect

    Montgomery, John V.; Gueretta, Jeanie

    2012-07-01

    The U.S. Department of Energy (DOE) is responsible for managing vast amounts of information documenting historical and current operations. This information is critical to the operations of the DOE Office of Legacy Management. Managing legacy records and information is challenging in terms of accessibility and changing technology. The Office of Legacy Management is meeting these challenges by making records and information management an organizational priority. The Office of Legacy Management mission is to manage DOE post-closure responsibilities at former Cold War weapons sites to ensure the future protection of human health and the environment. These responsibilities include environmental stewardship and long-term preservation and management of operational and environmental cleanup records associated with each site. A primary organizational goal for the Office of Legacy Management is to 'Preserve, Protect, and Share Records and Information'. Managing records for long-term preservation is an important responsibility. Adequate and dedicated resources and management support are required to perform this responsibility successfully. Records tell the story of an organization and may be required to defend an organization in court, provide historical information, identify lessons learned, or provide valuable information for researchers. Loss of records or the inability to retrieve records because of poor records management processes can have serious consequences and even lead to an organisation's downfall. Organizations must invest time and resources to establish a good records management program because of its significance to the organization as a whole. The Office of Legacy Management will continue to research and apply innovative ways of doing business to ensure that the organization stays at the forefront of effective records and information management. DOE is committed to preserving records that document our nation's Cold War legacy, and the Office of Legacy

  4. Dynamics of long-term genomic selection

    PubMed Central

    2010-01-01

    Background Simulation and empirical studies of genomic selection (GS) show accuracies sufficient to generate rapid gains in early selection cycles. Beyond those cycles, allele frequency changes, recombination, and inbreeding make analytical prediction of gain impossible. The impacts of GS on long-term gain should be studied prior to its implementation. Methods A simulation case-study of this issue was done for barley, an inbred crop. On the basis of marker data on 192 breeding lines from an elite six-row spring barley program, stochastic simulation was used to explore the effects of large or small initial training populations with heritabilities of 0.2 or 0.5, applying GS before or after phenotyping, and applying additional weight on low-frequency favorable marker alleles. Genomic predictions were from ridge regression or a Bayesian analysis. Results Assuming that applying GS prior to phenotyping shortened breeding cycle time by 50%, this practice strongly increased early selection gains but also caused the loss of many favorable QTL alleles, leading to loss of genetic variance, loss of GS accuracy, and a low selection plateau. Placing additional weight on low-frequency favorable marker alleles, however, allowed GS to increase their frequency earlier on, causing an initial increase in genetic variance. This dynamic led to higher long-term gain while mitigating losses in short-term gain. Weighted GS also increased the maintenance of marker polymorphism, ensuring that QTL-marker linkage disequilibrium was higher than in unweighted GS. Conclusions Losing favorable alleles that are in weak linkage disequilibrium with markers is perhaps inevitable when using GS. Placing additional weight on low-frequency favorable alleles, however, may reduce the rate of loss of such alleles to below that of phenotypic selection. Applying such weights at the beginning of GS implementation is important. PMID:20712894

  5. GPS-PWV Estimation and Analysis for CGPS Sites Operating in Mexico

    NASA Astrophysics Data System (ADS)

    Gutierrez, O.; Vazquez, G. E.; Bennett, R. A.; Adams, D. K.

    2014-12-01

    Eighty permanent Global Positioning System (GPS) tracking stations that belong to several networks spanning Mexico intended for diverse purposes and applications were used to estimate precipitable water vapor (PWV) using measurement series covering the period of 2000-2014. We extracted the GPS-PWV from the ionosphere-free double-difference carrier phase observations, processed using the GAMIT software. The GPS data were processed with a 30 s sampling rate, 15-degree cutoff angle, and precise GPS orbits disseminated by IGS. The time-varying part of the zenith wet delay was estimated using the Global Mapping Function (GMF), while the constant part is evaluated using the Neil tropospheric model. The data reduction to compute the zenith wet delay follows the step piecewise linear strategy, which is subsequently transformed to PWV estimated every 2-hr. Although there exist previous isolated studies for estimating PWV in Mexico, this study is an attempt to perform a more complete and comprehensive analysis of PWV estimation throughout the Mexican territory. Our resulting GPS-based PWV were compared to available PWV values for 30 stations that operate in Mexico and report the PWV to Suominet. This comparison revealed differences of 1 to 2 mm between the GPS-PWV solution and the PWV reported by Suominet. Accurate values of GPS-PWV will help enhance Mexico ability to investigate water vapor advection, convective and frontal rainfall and long-term climate variability.

  6. The comparison of the long term results of international time synchronization determinated by the two technologies of time transfer.

    NASA Astrophysics Data System (ADS)

    Hu, Jinlun

    The author carried out comparison and analysis for the long term results of international time synchronization which are determinated by the two technologies of time transfer (Loran-C and GPS). Some results of Shanghai Observatory time laboratory have been obtained.

  7. The Starkey project: long-term research for long-term management solutions.

    Treesearch

    Thomas M. Quigley; Michael J. Wisdom

    2004-01-01

    The Starkey Project is a unique, long-term research program designed to study the effects of key resource uses of national forests on mule deer (Odocoileus hemionus) and elk (Cervus elaphus) habitats and populations located at the Starkey Experimental Forest and Range (Starkey). The purpose of the project was to fill knowledge...

  8. Aggregated GPS tracking of vehicles and its use as a proxy of traffic-related air pollution emissions

    NASA Astrophysics Data System (ADS)

    Chen, Shimon; Bekhor, Shlomo; Yuval; Broday, David M.

    2016-10-01

    Most air quality models use traffic-related variables as an input. Previous studies estimated nearby vehicular activity through sporadic traffic counts or via traffic assignment models. Both methods have previously produced poor or no data for nights, weekends and holidays. Emerging technologies allow the estimation of traffic through passive monitoring of location-aware devices. Examples of such devices are GPS transceivers installed in vehicles. In this work, we studied traffic volumes that were derived from such data. Additionally, we used these data for estimating ambient nitrogen dioxide concentrations, using a non-linear optimisation model that includes basic dispersion properties. The GPS-derived data show great potential for use as a proxy for pollutant emissions from motor-vehicles.

  9. Contribution of various microenvironments to the daily personal exposure to ultrafine particles: Personal monitoring coupled with GPS tracking

    NASA Astrophysics Data System (ADS)

    Bekö, Gabriel; Kjeldsen, Birthe Uldahl; Olsen, Yulia; Schipperijn, Jasper; Wierzbicka, Aneta; Karottki, Dorina Gabriela; Toftum, Jørn; Loft, Steffen; Clausen, Geo

    2015-06-01

    Exposure to ultrafine particles (UFP) may have adverse health effects. Central monitoring stations do not represent the personal exposure to UFP accurately. Few studies have previously focused on personal exposure to UFP. Sixty non-smoking residents living in Copenhagen, Denmark were asked to carry a backpack equipped with a portable monitor, continuously recording particle number concentrations (PN), in order to measure the real-time individual exposure over a period of ˜48 h. A GPS logger was carried along with the particle monitor and allowed us to estimate the contribution of UFP exposure occurring in various microenvironments (residence, during active and passive transport, other indoor and outdoor environments) to the total daily exposure. On average, the fractional contribution of each microenvironment to the daily integrated personal exposure roughly corresponded to the fractions of the day the subjects spent in each microenvironment. The home environment accounted for 50% of the daily personal exposure. Indoor environments other than home or vehicles contributed with ˜40%. The highest median UFP concentration was obtained during passive transport (vehicles). However, being in transit or outdoors contributed 5% or less to the daily exposure. Additionally, the subjects recorded in a diary the periods when they were at home. With this approach, 66% of the total daily exposure was attributable to the home environment. The subjects spent 28% more time at home according to the diary, compared to the GPS. These results may indicate limitations of using diaries, but also possible inaccuracy and miss-classification in the GPS data.

  10. Ambient Tremor Triggered by Long-term Slow Slip Event in Bungo Channel, Southwest Japan

    NASA Astrophysics Data System (ADS)

    Obara, K.; Hirose, H.; Matsuzawa, T.; Tanaka, S.; Maeda, T.

    2014-12-01

    Episodic tremor and slip (ETS) is a stick-slip in the transition zone between locked and stable sliding zones on the plate interface in Southwest Japan and Cascadia. ETS episode with duration of several days usually recurs at interval of several months at each segment. On the other hand, in the Bungo channel region where is the western edge of the ETS zone in SW Japan, tremor activity continued for several months during the long-term slow slip event (SSE) in 2003 and 2010. In this paper, the relationship between long-term SSE and surrounded triggered tremor is discussed. Tremor triggered by the long-term SSE is spatially localized in the narrow width of about 10 km at the shallowest part of the tremor zone, and at the neighboring area just downdip from the source fault of the SSE. The frequency distribution of tremor along the dip direction during the SSE period is consistent with the spatial distribution of total slip estimated for 2010 SSE. Therefore, the slip of the long-term SSE penetrated in the ETS zone may generate tremor. The daily number of the activated tremor is 12-14 during the SSE; however, it is 40-50 for regular ETS episode during the inter-SSE period. On the other hand, slip rates of the long-term SSE and ETS are typically 1 mm/d and 3 mm/d, respectively. Therefore, tremor rate may be controlled by slip rate. After SSEs in 2003 and 2010, tremor activity seems to slightly increase in the east region within 50 km from the triggered tremor area. Such 7-year period variation in tremor activity is observed in only the shallower side of the tremor zone. Moreover, pattern of the long-term variation seems to slightly migrate to east during a few years. We interpret that a tiny transient slip after the long-term SSE slowly propagates between transition and locked zones. Tremor activity at the shallowest part of the tremor zone in the Bungo channel continued longer than that of regular ETS in the late 2006 during the inter-SSE period. Associated tiny GPS

  11. Long-term soil monitoring at U.S. Geological Survey reference watersheds

    USGS Publications Warehouse

    McHale, Michael R.; Siemion, Jason; Lawrence, Gregory B.; Mast, M. Alisa

    2014-01-01

    Monitoring the environment by making repeated measurements through time is essential to evaluate and track the health of ecosystems (fig. 1). Long-term datasets produced by such monitoring are indispensable for evaluating the effectiveness of environmental legislation and for designing mitigation strategies to address environmental changes in an era when human activities are altering the environment locally and globally.

  12. Unhappily Ever After: Effects of Long-Term, Low-Quality Marriages on Well-Being

    ERIC Educational Resources Information Center

    Hawkins, Daniel N.; Booth, Alan

    2005-01-01

    The present study shows that long-term, low-quality marriages have significant negative effects on overall well-being. We utilize a nationally representative longitudinal study with a multi-item marital quality scale that allows us to track unhappy marriages over a 12-year period and to assess marital happiness along many dimensions. Remaining…

  13. 17 CFR 256.224 - Other long-term debt.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 6. Long-Term Debt § 256.224 Other long-term debt. This account shall include all long...

  14. 17 CFR 256.224 - Other long-term debt.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 6. Long-Term Debt § 256.224 Other long-term debt. This account shall include all long...

  15. Treatment for childhood cancer -- long-term risks

    MedlinePlus

    ... ency/patientinstructions/000849.htm Treatment for childhood cancer - long-term risks To use the sharing features on this ... has. Being aware of your child's risk of long-term health problems can help you follow-up with ...

  16. 22 CFR 228.12 - Long-term leases.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SERVICES FINANCED BY USAID Conditions Governing Source and Nationality of Commodity Procurement Transactions for USAID Financing § 228.12 Long-term leases. Any commodity obtained under a long-term lease...

  17. 22 CFR 228.18 - Long-term leases.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... USAID Conditions Governing Source and Nationality of Commodity and Service Procurement Transactions for USAID Financing § 228.18 Long-term leases. Any commodity obtained under a long-term lease agreement as...

  18. 22 CFR 228.18 - Long-term leases.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... USAID Conditions Governing Source and Nationality of Commodity and Service Procurement Transactions for USAID Financing § 228.18 Long-term leases. Any commodity obtained under a long-term lease agreement as...

  19. 22 CFR 228.18 - Long-term leases.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... USAID Conditions Governing Source and Nationality of Commodity and Service Procurement Transactions for USAID Financing § 228.18 Long-term leases. Any commodity obtained under a long-term lease agreement as...

  20. 22 CFR 228.12 - Long-term leases.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SERVICES FINANCED BY USAID Conditions Governing Source and Nationality of Commodity Procurement Transactions for USAID Financing § 228.12 Long-term leases. Any commodity obtained under a long-term lease...

  1. LONG-TERM MONITORING SENSOR NETWORK

    SciTech Connect

    Stephen P. Farrington; John W. Haas; Neal Van Wyck

    2003-10-16

    Long-term monitoring (LTM) associated with subsurface contamination sites is a key element of Long Term Stewardship and Legacy Management across the Department of Energy (DOE) complex. However, both within the DOE and elsewhere, LTM is an expensive endeavor, often exceeding the costs of the remediation phase of a clean-up project. The primary contributors to LTM costs are associated with labor. Sample collection, storage, preparation, analysis, and reporting can add a significant financial burden to project expense when extended over many years. Development of unattended, in situ monitoring networks capable of providing quantitative data satisfactory to regulatory concerns has the potential to significantly reduce LTM costs. But survival and dependable operation in a difficult environment is a common obstacle to widespread use across the DOE complex or elsewhere. Deploying almost any sensor in the subsurface for extended periods of time will expose it to chemical and microbial degradation. Over the time-scales required for in situ LTM, even the most advanced sensor systems may be rendered useless. Frequent replacement or servicing (cleaning) of sensors is expensive and labor intensive, offsetting most, if not all, of the cost savings realized with unattended, in situ sensors. To enable facile, remote monitoring of contaminants and other subsurface parameters over prolonged periods, Applied Research Associates, Inc has been working to develop an advanced LTM sensor network consisting of three key elements: (1) an anti-fouling sensor chamber that can accommodate a variety of chemical and physical measurement devices based on electrochemical, optical and other techniques; (2) two rapid, cost effective, and gentle means of emplacing sensor packages either at precise locations directly in the subsurface or in pre-existing monitoring wells; and (3) a web browser-based data acquisition and control system (WebDACS) utilizing field-networked microprocessor-controlled smart

  2. Robotics for Long-Term Monitoring

    SciTech Connect

    Shahin, Sarkis; Duran, Celso

    2002-07-01

    While long-term monitoring and stewardship means many things to many people, DOE has defined it as The physical controls, institutions, information, and other mechanisms needed to ensure protection of people and the environment at sites where DOE has completed or plans to complete cleanup (e.g., landfill closures, remedial actions, and facility stabilization). Across the United States, there are thousands of contaminated sites with multiple contaminants released from multiple sources where contaminants have transported and commingled. The U.S. government and U.S. industry are responsible for most of the contamination and are landowners of many of these contaminated properties. These sites must be surveyed periodically for various criteria including structural deterioration, water intrusion, integrity of storage containers, atmospheric conditions, and hazardous substance release. The surveys, however, are intrusive, time-consuming, and expensive and expose survey personnel to radioactive contamination. In long-term monitoring, there's a need for an automated system that will gather and report data from sensors without costly human labor. In most cases, a SCADA (Supervisory Control and Data Acquisition) unit is used to collect and report data from a remote location. A SCADA unit consists of an embedded computer with data acquisition capabilities. The unit can be configured with various sensors placed in different areas of the site to be monitored. A system of this type is static, i.e., the sensors, once placed, cannot be moved to other locations within the site. For those applications where the number of sampling locations would require too many sensors, or where exact location of future problems is unknown, a mobile sensing platform is an ideal solution. In many facilities that undergo regular inspections, the number of video cameras and air monitors required to eliminate the need for human inspections is very large and far too costly. HCET's remote harsh

  3. Long-term Changes in Tropospheric Ozone

    NASA Astrophysics Data System (ADS)

    Oltmans, S.; Lefohn, A.; Galbally, I.; Scheel, E.; Bodeker, G.; Brunke, E.; Claude, H.; Tarasick, D.; Simmonds, P.; Anlauf, K.; Schmidlin, F.; Akagi, K.; Redondas, A.

    2006-05-01

    Tropospheric ozone measurements from a selected network of surface and ozonesonde sites are used to give a broad geographic picture of long-term variations. The picture of long-term tropospheric ozone changes is a varied one in terms of both the sign and magnitude of trends and in the possible causes for the changes. At mid latitudes of the S.H. three time series of ~20 years in length agree in showing increases that are strongest in the austral spring (August-October). Profile measurements show this increase extending through the mid troposphere but not into the highest levels of the troposphere. In the N.H. in the Arctic a period of declining ozone in the troposphere through the 1980s into the mid 1990s has reversed and the overall change is small. The decadal-scale variations in the troposphere in this region are related in part to changes in the lowermost stratosphere. At mid latitudes in the N.H., continental Europe and Japan showed significant increases in the 1970s and 1980s. Over North America rises in the 1970s are less than those seen in Europe and Japan, suggesting significant regional differences. In all three of these mid latitude, continental regions tropospheric ozone amounts appear to have leveled off or in some cases declined in the more recent decades. Over the North Atlantic three widely separated sites show significant increases since the late 1990s that may have peaked in recent years. In the N.H. tropics both the surface record and the ozonesondes in Hawaii show a significant increase in the autumn months in the most recent decade compared to earlier periods that drives the overall increase seen in the 30 year record. This appears to be related to a shift in the transport pattern during this season with more frequent flow from higher latitudes in the latest decade. The pattern of change, with the largest increases in the N.H. coming prior to the mid 1980s, suggests that increased positive radiative forcing due to tropospheric ozone was felt

  4. Evaluating Long-Term Care Through the Humanbecoming Lens.

    PubMed

    Hart, Judith D

    2015-10-01

    The author describes evaluating long-term care from the humanbecoming perspective. Three core ideas are presented related to dignity and living quality, and how the humanbecoming perspective can be incorporated into long-term care evaluations that make a difference to the residents, caregivers, management, and to the outcomes of long-term care. This approach from the humanbecoming perspective can enrich evaluative information, influence long-term care outcomes, and ensure human dignity for all concerned.

  5. Long-term Variability of Beach Cusps

    NASA Astrophysics Data System (ADS)

    Pianca, C.; Holman, R. A.; Siegle, E.

    2016-02-01

    The most curious morphological features observed on beaches are the cusps. Due to their rhythmic spacing, beach cusps have attracted many observers and many, often contradictory, theories as to their form. Moreover, most of the research about beach cusps has focused on their formation. Few had available long time series to study such things as the variability of alongshore and cross-shore position and spacing on the cusp field, the presence, longevity and interactions between higher and lower sets of cusps, and the processes by which cusp fields extend, shrink or change length scale. The purpose of this work is to use long-term data sets of video images from two study sites, an intermediate (Duck, USA, 26 years) and a reflective beach (Massaguaçu, Brazil, 3 years), to investigate the temporal and spatial changes of cusps conditions. Time-evolving shoreline data were first extracted using an algorithm called ASLIM (Pianca et al 2015). Cusps were then identified based on the band-passed variability of time exposure image data about this shoreline as a function of elevation relative to MSL. The identified beaches cusps will be analyzed for cusp spacing, positions (upper or lower cusps), alongshore variability, merging events, percentage of cusp events, patterns of the events and time scales of variability. Finally, the relationship of these characteristics to environmental conditions (wave, tides, beach conditions) will be studied.

  6. Long-term adequacy of metal resources

    USGS Publications Warehouse

    Singer, D.A.

    1977-01-01

    Although the earth's crust contains vast quantities of metals, extraction technologies and associated costs are inextricably bound to three fundamental geological factors - the amount of metal available in the earth's crust in each range of grades, the mineralogical form and chemical state of the metal, and the spatial distribution of the metal. The energy required to recover a given amount of metal increases substantially as grade declines. Most metal is produced from sulphide or oxide minerals, whereas most metal in the crust may be locked in the structures of the more refractory silicates. Recovery from silicate minerals could require orders of magnitude more energy than that used at present as also could exploitation of small, widely scattered or thin, deeply buried deposits. Although specific information on the fundamental factors is not available, each factor must in turn tend to further restrict exploitation. Independence of average grade and tonnage for many deposit types further reduces the availability of rock as a source of metal. In the long term, effects of these factors will be large increases in price for many metals. ?? 1977.

  7. Long term results of childhood dysphonia treatment.

    PubMed

    Mackiewicz-Nartowicz, Hanna; Sinkiewicz, Anna; Bielecka, Arleta; Owczarzak, Hanna; Mackiewicz-Milewska, Magdalena; Winiarski, Piotr

    2014-05-01

    The aim of this study was to assess the long term results of treatment and rehabilitation of childhood dysphonia. This study included a group of adolescents (n=29) aged from 15 to 20 who were treated due to pediatric hyperfunctional dysphonia and soft vocal fold nodules during their pre-mutational period (i.e. between 5 and 12 years of age). The pre-mutational therapy was comprised of proper breathing pattern training, voice exercises and psychological counseling. Laryngostroboscopic examination and perceptual analysis of voice were performed in each patient before treatment and one to four years after mutation was complete. The laryngostroboscopic findings, i.e. symmetry, amplitude, mucosal wave and vocal fold closure, were graded with NAPZ scale, and the GRBAS scale was used for the perceptual voice analysis. Complete regression of the childhood dysphonia was observed in all male patients (n=14). Voice disorders regressed completely also in 8 out of 15 girls, but symptoms of dysphonia documented on perceptual scale persisted in the remaining seven patients. Complex voice therapy implemented in adolescence should be considered as either the treatment or preventive measure of persistent voice strain, especially in girls. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  8. Long-term corrosion testing pan.

    SciTech Connect

    Wall, Frederick Douglas; Brown, Neil R.

    2008-08-01

    This document describes the testing and facility requirements to support the Yucca Mountain Project long-term corrosion testing needs. The purpose of this document is to describe a corrosion testing program that will (a) reduce model uncertainty and variability, (b) reduce the reliance upon overly conservative assumptions, and (c) improve model defensibility. Test matrices were developed for 17 topical areas (tasks): each matrix corresponds to a specific test activity that is a subset of the total work performed in a task. A future document will identify which of these activities are considered to be performance confirmation activities. Detailed matrices are provided for FY08, FY09 and FY10 and rough order estimates are provided for FY11-17. Criteria for the selection of appropriate test facilities were developed through a meeting of Lead Lab and DOE personnel on October 16-17, 2007. These criteria were applied to the testing activities and recommendations were made for the facility types appropriate to carry out each activity. The facility requirements for each activity were assessed and activities were identified that can not be performed with currently available facilities. Based on this assessment, a total of approximately 10,000 square feet of facility space is recommended to meet all future testing needs, given that all testing is consolidated to a single location. This report is a revision to SAND2007-7027 to address DOE comments and add a series of tests to address NWTRB recommendations.

  9. Long-term data storage in diamond.

    PubMed

    Dhomkar, Siddharth; Henshaw, Jacob; Jayakumar, Harishankar; Meriles, Carlos A

    2016-10-01

    The negatively charged nitrogen vacancy (NV(-)) center in diamond is the focus of widespread attention for applications ranging from quantum information processing to nanoscale metrology. Although most work so far has focused on the NV(-) optical and spin properties, control of the charge state promises complementary opportunities. One intriguing possibility is the long-term storage of information, a notion we hereby introduce using NV-rich, type 1b diamond. As a proof of principle, we use multicolor optical microscopy to read, write, and reset arbitrary data sets with two-dimensional (2D) binary bit density comparable to present digital-video-disk (DVD) technology. Leveraging on the singular dynamics of NV(-) ionization, we encode information on different planes of the diamond crystal with no cross-talk, hence extending the storage capacity to three dimensions. Furthermore, we correlate the center's charge state and the nuclear spin polarization of the nitrogen host and show that the latter is robust to a cycle of NV(-) ionization and recharge. In combination with super-resolution microscopy techniques, these observations provide a route toward subdiffraction NV charge control, a regime where the storage capacity could exceed present technologies.

  10. Long-term physiological consequences of pneumonectomy.

    PubMed

    Deslauriers, Jean; Ugalde, Paula; Miro, Santiago; Deslauriers, Deborah R; Ferland, Sylvie; Bergeron, Sébastien; Lacasse, Yves; Provencher, Steeve

    2011-01-01

    Ever since the first successful pneumonectomy for lung cancer was performed in 1933, a number of largely historical reports have attempted to look at the physiological consequences of this operation in order to define patient long-term functional status. The pertinence of these contributions is, however, limited because most were performed in patients who had their pneumonectomy for benign diseases or were carried out in small and heterogeneous populations. Thus, several surgical myths and beliefs such as phrenic nerve interruption at the time of operation might be desirable, marked hyperinflation of the residual lung is associated with reduced lung function, and patients develop pulmonary hypertension over time and have poor exercise tolerance have persisted over the years. Our findings based on a study of 100 patients evaluated 5 or more years after surgery (mean follow-up time, 9.1 ± 2.8 years [5.0-14.7 years]) show that most patients can adjust to living with only one lung and are thus able to live a near-normal life. Although diaphragmatic paralysis is characterized by significant alterations in respiratory function, hyperinflation of the residual lung is beneficial. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Long-term predictions using natural analogues

    SciTech Connect

    Ewing, R.C.

    1995-09-01

    One of the unique and scientifically most challenging aspects of nuclear waste isolation is the extrapolation of short-term laboratory data (hours to years) to the long time periods (10{sup 3}-10{sup 5} years) required by regulatory agencies for performance assessment. The direct validation of these extrapolations is not possible, but methods must be developed to demonstrate compliance with government regulations and to satisfy the lay public that there is a demonstrable and reasonable basis for accepting the long-term extrapolations. Natural systems (e.g., {open_quotes}natural analogues{close_quotes}) provide perhaps the only means of partial {open_quotes}validation,{close_quotes} as well as data that may be used directly in the models that are used in the extrapolation. Natural systems provide data on very large spatial (nm to km) and temporal (10{sup 3}-10{sup 8} years) scales and in highly complex terranes in which unknown synergisms may affect radionuclide migration. This paper reviews the application (and most importantly, the limitations) of data from natural analogue systems to the {open_quotes}validation{close_quotes} of performance assessments.

  12. Long-term corrosion testing plan.

    SciTech Connect

    Wall, Frederick Douglas; Brown, Neil R.

    2009-02-01

    This document describes the testing and facility requirements to support the Yucca Mountain Project long-term corrosion testing program. The purpose of this document is to describe a corrosion testing program that will (a) reduce model uncertainty and variability, (b) reduce the reliance upon overly conservative assumptions, and (c) improve model defensibility. Test matrices were developed for 17 topical areas (tasks): each matrix corresponds to a specific test activity that is a subset of the total work performed in a task. A future document will identify which of these activities are considered to be performance confirmation activities. Detailed matrices are provided for FY08, FY09 and FY10 and rough order estimates are provided for FY11-17. Criteria for the selection of appropriate test facilities were developed through a meeting of Lead Lab and DOE personnel on October 16-17, 2007. These criteria were applied to the testing activities and recommendations were made for the facility types appropriate to carry out each activity. The facility requirements for each activity were assessed and activities were identified that can not be performed with currently available facilities. Based on this assessment, a total of approximately 10,000 square feet of facility space is recommended to accommodate all future testing, given that all testing is consolidated to a single location. This report is a revision to SAND2008-4922 to address DOE comments.

  13. Long-term treatment outcome in acromegaly.

    PubMed

    Holdaway, I M; Rajasoorya, C R; Gamble, G D; Stewart, A W

    2003-08-01

    A number of groups have developed guidelines to indicate whether an individual with acromegaly has been cured by treatment. However, studies to date do not provide a robust definition of biochemical remission of the disorder based on correlation with long-term outcome. Available data suggest that those with a random serum growth hormone (GH) level of <2.5 microg/l, or a glucose-suppressed GH level of <1 microg/l following treatment have mortality figures indistinguishable from the general population. However, the confidence limits for these mortality estimates are quite wide. It remains possible that growth hormone levels lower than 1 microg/l for random samples, or even lower when using ultrasensitive GH assays, may indicate superior outcome, but this remains to be confirmed. There are limited data relating serum insulin-like growth factor-I (IGF-I) levels to outcome, although normalisation of serum IGF-I clearly improves outcome compared with continued elevation of measurements after treatment. Current evidence suggests that a post-treatment random serum GH <2.5 microg/l and a normal serum IGF-I value defines biochemical cure. Available data suggest that achieving similar growth hormone levels after treatment also reduces the prevalence of chronic complications of the disorder, which is subsequently reflected in improved mortality.

  14. Dental hygienists and long-term care.

    PubMed

    Ablah, C R; Pickard, R B

    1998-01-01

    This study examined the willingness of dental hygienists to work in long-term care (LTC) facilities providing oral health care to the elderly. In August 1995, a mail survey of all 839 licensed and practicing dental hygienists in Kansas was conducted. Respondents were asked about their reasons for choosing dental hygiene as a career, perceptions of the adequacy of their education, satisfaction with their work, interest in working with elderly patients, and whether general supervision would influence their willingness to practice in LTC settings. Response rate was 69 percent, with 582 usable questionnaires returned. Data were analyzed using descriptive statistics and chi-square tests of significance. The results showed an overwhelming majority (94 percent) of respondents would be willing to work, at least on occasion, in a LTC facility. However, few were interested in full-time geriatric practice. Those indicating a willingness to practice regularly with the elderly, at least part time, were typically less experienced in their field and more likely to perceive their education as having adequately prepared them to care for older patients. The findings demonstrate dental hygienists' willingness to provide dental care for older adults. To optimize this resource, appropriate education is needed so that students and current practitioners master the distinctive skills necessary to care for this population.

  15. Long-Term Consequences of Neonatal Injury

    PubMed Central

    Beggs, Simon

    2015-01-01

    The maturation of the central nervous system’s (CNS’s) sensory connectivity is driven by modality-specific sensory input in early life. For the somatosensory system, this input is the physical, tactile interaction with the environment. Nociceptive circuitry is functioning at the time of birth; however, there is still considerable organization and refinement of this circuitry that occurs postnatally, before full discrimination of tactile and noxious input is possible. This fine-tuning involves separation of tactile and nociceptive afferent input to the spinal cord’s dorsal horn and the maturation of local and descending inhibitory circuitry. Disruption of that input in early postnatal life (for example, by tissue injury or other noxious stimulus), can have a profound influence on subsequent development, and consequently the mature functioning of pain systems. In this review, the impact of neonatal surgical incision on nociceptive circuitry is discussed in terms of the underlying developmental neurobiology. The changes are complex, occurring at multiple anatomical sites within the CNS, and including both neuronal and glial cell populations. The altered sensory input from neonatal injury selectively modulates neuronal excitability within the spinal cord, disrupts inhibitory control, and primes the immune system, all of which contribute to the adverse long-term consequences of early pain exposure. PMID:26174217

  16. Intermediate- and long-term earthquake prediction.

    PubMed

    Sykes, L R

    1996-04-30

    Progress in long- and intermediate-term earthquake prediction is reviewed emphasizing results from California. Earthquake prediction as a scientific discipline is still in its infancy. Probabilistic estimates that segments of several faults in California will be the sites of large shocks in the next 30 years are now generally accepted and widely used. Several examples are presented of changes in rates of moderate-size earthquakes and seismic moment release on time scales of a few to 30 years that occurred prior to large shocks. A distinction is made between large earthquakes that rupture the entire downdip width of the outer brittle part of the earth's crust and small shocks that do not. Large events occur quasi-periodically in time along a fault segment and happen much more often than predicted from the rates of small shocks along that segment. I am moderately optimistic about improving predictions of large events for time scales of a few to 30 years although little work of that type is currently underway in the United States. Precursory effects, like the changes in stress they reflect, should be examined from a tensorial rather than a scalar perspective. A broad pattern of increased numbers of moderate-size shocks in southern California since 1986 resembles the pattern in the 25 years before the great 1906 earthquake. Since it may be a long-term precursor to a great event on the southern San Andreas fault, that area deserves detailed intensified study.

  17. Intermediate- and long-term earthquake prediction.

    PubMed Central

    Sykes, L R

    1996-01-01

    Progress in long- and intermediate-term earthquake prediction is reviewed emphasizing results from California. Earthquake prediction as a scientific discipline is still in its infancy. Probabilistic estimates that segments of several faults in California will be the sites of large shocks in the next 30 years are now generally accepted and widely used. Several examples are presented of changes in rates of moderate-size earthquakes and seismic moment release on time scales of a few to 30 years that occurred prior to large shocks. A distinction is made between large earthquakes that rupture the entire downdip width of the outer brittle part of the earth's crust and small shocks that do not. Large events occur quasi-periodically in time along a fault segment and happen much more often than predicted from the rates of small shocks along that segment. I am moderately optimistic about improving predictions of large events for time scales of a few to 30 years although little work of that type is currently underway in the United States. Precursory effects, like the changes in stress they reflect, should be examined from a tensorial rather than a scalar perspective. A broad pattern of increased numbers of moderate-size shocks in southern California since 1986 resembles the pattern in the 25 years before the great 1906 earthquake. Since it may be a long-term precursor to a great event on the southern San Andreas fault, that area deserves detailed intensified study. Images Fig. 1 PMID:11607658

  18. Transuranic waste: long-term planning

    SciTech Connect

    Young, K.C.

    1985-07-01

    Societal concerns for the safe handling and disposal of toxic waste are behind many of the regulations and the control measures in effect today. Transuranic waste, a specific category of toxic (radioactive) waste, serves as a good example of how regulations and controls impact changes in waste processing - and vice versa. As problems would arise with waste processing, changes would be instituted. These changes improved techniques for handling and disposal of transuranic waste, reduced the risk of breached containment, and were usually linked with regulatory changes. Today, however, we face a greater public awareness of and concern for toxic waste control; thus, we must anticipate potential problems and work on resolving them before they can become real problems. System safety analyses are valuable aids in long-term planning for operations involving transuranic as well as other toxic materials. Examples of specific system safety analytical methods demonstrate how problems can be anticipated and resolution initiated in a timely manner having minimal impacts upon allocation of resource and operational goals. 7 refs., 1 fig.

  19. The long-term variability of Vega

    NASA Astrophysics Data System (ADS)

    Butkovskaya, V.; Plachinda, S.; Valyavin, G.; Baklanova, D.; Lee, B.-C.

    2011-12-01

    Over the time of 60 years Vega (α Lyrae = HD 172167, A0V) has been generally accepted as a standard star in the near-infrared, optical, and ultraviolet regions. But is the spectrophotometric standard Vega really non-variable star? Researchers give very different answers to this question. We aim to search a periodicity in our results of spectropolarimetric study of Vega, namely periodic variations in equivalent width of the spectral lines and longitudinal magnetic field measurements. High-accuracy spectropolarimetric observations of Vega have been performed during 26 nights from 1997 to 2010 using the Coudé spectrograph of the 2.6-m Shain reflector at the Crimean Astrophysical Observatory (CrAO, Ukraine) and during 4 nights in 2007 and 2008 using the echelle spectrograph BOES at the Bohyunsan Optical Astronomy Observatory (BOAO, South Korea). The long-term (year-to-year) variability of Vega was confirmed. It was concluded that this variability does not have magnetic nature. The paper is dedicated to the memory of V.P. Merezhin.

  20. Economic efficiency, IRPs and long term contracts

    SciTech Connect

    Sutherland, R.J.

    1993-04-30

    There is no market failure that warrants utility regulation of the construction of new generating plants, the supply of energy efficiency or the purchase of fuel under contract. The natural monopoly problem applies to the distribution of electricity and gas, not to generation, energy conservation, or gas purchases. Utility regulation magnifies a market failure, which is the principal agent problem. Regulatory allowance of utilities signing long term fixed price contracts and undertaking conservation measures result in costs and risks being shifted to ratepayers that would not occur under competitive market conditions. Economic efficiency would be enhanced if cost of service regulation of electric and gas utilities were replaced by a competitive market process for the construction of new power plants, utility conservation programs and contracts to purchase fuel. Conservation measures could be supplied by energy service companies. Gas merchants could provide gas and energy conservation directly to ultimate customers, if they had access to LDC pipelines. With a competitive market established to sell gas and energy services, contracts and conservation measures would not require cost-of- service regulation.

  1. Long-Term Soft Denture Lining Materials

    PubMed Central

    Chladek, Grzegorz; Żmudzki, Jarosław; Kasperski, Jacek

    2014-01-01

    Long-term soft denture lining (LTSDL) materials are used to alleviate the trauma associated with wearing complete dentures. Despite their established clinical efficacy, the use of LTSDLs has been limited due to the unfavorable effects of the oral environment on some of their mechanical and performance characteristics. The unresolved issue of LTSDL colonization by Candida albicans is particularly problematic. Silicone-based LTSDL (SLTSDL) materials, which are characterized by more stable hardness, sorption and solubility than acrylic-based LTSDLs (ALTSDLs), are currently the most commonly used LTSDLs. However, SLTSDLs are more prone to debonding from the denture base. Moreover, due to their limitations, the available methods for determining bond strength do not fully reflect the actual stability of these materials under clinical conditions. SLTSDL materials exhibit favorable viscoelastic properties compared with ALTSDLs. Furthermore, all of the lining materials exhibit an aging solution-specific tendency toward discoloration, and the available cleansers are not fully effective and can alter the mechanical properties of LTSDLs. Future studies are needed to improve the microbiological resistance of LTSDLs, as well as some of their performance characteristics. PMID:28788163

  2. Long-term data storage in diamond

    PubMed Central

    Dhomkar, Siddharth; Henshaw, Jacob; Jayakumar, Harishankar; Meriles, Carlos A.

    2016-01-01

    The negatively charged nitrogen vacancy (NV−) center in diamond is the focus of widespread attention for applications ranging from quantum information processing to nanoscale metrology. Although most work so far has focused on the NV− optical and spin properties, control of the charge state promises complementary opportunities. One intriguing possibility is the long-term storage of information, a notion we hereby introduce using NV-rich, type 1b diamond. As a proof of principle, we use multicolor optical microscopy to read, write, and reset arbitrary data sets with two-dimensional (2D) binary bit density comparable to present digital-video-disk (DVD) technology. Leveraging on the singular dynamics of NV− ionization, we encode information on different planes of the diamond crystal with no cross-talk, hence extending the storage capacity to three dimensions. Furthermore, we correlate the center’s charge state and the nuclear spin polarization of the nitrogen host and show that the latter is robust to a cycle of NV− ionization and recharge. In combination with super-resolution microscopy techniques, these observations provide a route toward subdiffraction NV charge control, a regime where the storage capacity could exceed present technologies. PMID:27819045

  3. Long-term potentiation: peeling the onion.

    PubMed

    Nicoll, Roger A; Roche, Katherine W

    2013-11-01

    Since the discovery of long-term potentiation (LTP), thousands of papers have been published on this phenomenon. With this massive amount of information, it is often difficult, especially for someone not directly involved in the field, not to be overwhelmed. The goal of this review is to peel away as many layers as possible, and probe the core properties of LTP. We would argue that the many dozens of proteins that have been implicated in the phenomenon are not essential, but rather modulate, often in indirect ways, the threshold and/or magnitude of LTP. What is required is NMDA receptor activation followed by CaMKII activation. The consequence of CaMKII activation is the rapid recruitment of AMPA receptors to the synapse. This recruitment is independent of AMPA receptor subunit type, but absolutely requires an adequate pool of surface receptors. An important unresolved issue is how exactly CaMKII activation leads to modifications in the PSD to allow rapid enrichment. This article is part of the Special Issue entitled 'Glutamate Receptor-Dependent Synaptic Plasticity'.

  4. Neurological long term consequences of deep diving.

    PubMed Central

    Todnem, K; Nyland, H; Skeidsvoll, H; Svihus, R; Rinck, P; Kambestad, B K; Riise, T; Aarli, J A

    1991-01-01

    Forty commercial saturation divers, mean age 34.9 (range 24-49) years, were examined one to seven years after their last deep dive (190-500 metres of seawater). Four had by then lost their divers' licence because of neurological problems. Twenty seven (68%) had been selected by neurological examination and electroencephalography before the deep dives. The control group consisted of 100 men, mean age 34.0 (range 22-48) years. The divers reported significantly more symptoms from the nervous system. Concentration difficulties and paraesthesia in feet and hands were common. They had more abnormal neurological findings by neurological examination compatible with dysfunction in the lumbar spinal cord or roots. They also had a larger proportion of abnormal electroencephalograms than the controls. The neurological symptoms and findings were highly significantly correlated with exposure to deep diving (depth included), but even more significantly correlated to air and saturation diving and prevalence of decompression sickness. Visual evoked potentials, brainstem auditory evoked potentials, and magnetic resonance imaging of the brain did not show more abnormal findings in the divers. Four (10%) divers had had episodes of cerebral dysfunction during or after the dives; two had had seizures, one had had transitory cerebral ischaemia and one had had transitory global amnesia. It is concluded that deep diving may have a long term effect on the nervous system of the divers. PMID:2025592

  5. Long-term in vivo pineal microdialysis.

    PubMed

    Sun, Xing; Liu, Tiecheng; Deng, Jie; Borjigin, Jimo

    2003-09-01

    This study describes the development of a new technique for long-term measurement of daily 5-hydroxytryptamine (5-HT) and melatonin contents in the pineal gland of freely moving rats. The technique features a number of novel improvements over previous protocols. It allows visualization of the pineal gland for accurate targeting of the guide cannula, which minimizes bleeding; incurs no direct injury to the surrounding brain tissues; and causes no interference with the sympathetic innervation from the superior cervical ganglia. Robust releases of melatonin and indole precursors were continuously monitored quantitatively and reproducibly for more than 2 wk in the same animal. In addition, effects of pharmacological agents on in vivo pineal circadian rhythms can be studied reproducibly over time, and gene expression profiles can be correlated with physiological consequences in single animals. Using these approaches, it is found that beta-adrenergic activation leads to decreased release of 5-HT, and that increased cAMP signaling in vivo results in activation of N-acetyltransferase gene induction and melatonin production. These studies will enhance the understanding of signaling pathways that regulate pineal 5-HT and melatonin synthesis and secretion.

  6. [Long-term stability of orthodontic treatment].

    PubMed

    Kuijpers-Jagtman, A M; Al Yami, E A; van 't Hof, M A

    2000-04-01

    Aim of this study was to assess long-term stability of orthodontic treatment in a sample of 1016 patients until 10 years postretention. Treatment outcome was measured with the PAR-index at 6 different stages. The mean age of the patients was 12.0 +/- 3.1 year at the start of treatment to 26.3 +/- 2.9 year 10 years postretention. The results show that 67% of the orthodontic treatment result, as measured with the PAR-index, was maintained 10 years postretention. The PAR-scores for the midline and the open bite remained about the same over the years. However, the scores for the lateral occlusion, overjet, reversed overjet, overbite, and contact point displacement of the upper and lower front teeth increased gradually over time. Nearly 50% of the total relapse took place the first two years after retention. The largest change was found for the position of the lower incisors. Ten years postretention their position was even worse than at the start of treatment.

  7. Legislation on Long-Term Care Insurance. Report No. 11.

    ERIC Educational Resources Information Center

    Wisconsin State Legislative Council, Madison.

    This report presents Wisconsin state legislation on long-term care insurance. Part I summarizes key provisions of six 1987 assembly bills concerned with long-term care insurance. Part II describes activities of the Wisconsin State Legislative Council's Special Committee on Long-Term Health Care Insurance. Part III provides background information…

  8. 3 CFR - Long-Term Gulf Coast Restoration Support Plan

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 3 The President 1 2011-01-01 2011-01-01 false Long-Term Gulf Coast Restoration Support Plan Presidential Documents Other Presidential Documents Memorandum of June 30, 2010 Long-Term Gulf Coast... help the Gulf Coast and its people recover from this tragedy. A long-term plan to restore the unique...

  9. Long-term variations of muon flux angular distribution

    NASA Astrophysics Data System (ADS)

    Shutenko, V. V.; Astapov, I. I.; Barbashina, N. S.; Dmitrieva, A. N.; Kokoulin, R. P.; Kompaniets, K. G.; Petrukhin, A. A.; Yashin, I. I.

    2013-02-01

    Intensity of the atmospheric muon flux depends on a number of factors: energy spectrum of primary cosmic rays (PCR), heliospheric conditions, state of the magnetosphere and atmosphere of the Earth. The wide-aperture muon hodoscope URAGAN (Moscow, Russia, 55.7° N, 37.7° E, 173 m a.s.l.) makes it possible to investigate not only variations of the intensity of muon flux, but also temporal changes of its angular distribution. For the analysis of angular distribution variations, the vector of local anisotropy is used. The vector of local anisotropy is the sum of individual vectors (directions of the reconstructed muon tracks) normalized to the total number of reconstructed tracks. The vector of local anisotropy and its projections show different sensitivities to parameters of the processes of modulation of PCR in the heliosphere and the Earth's magnetosphere, and the passage of secondary cosmic rays through the terrestrial atmosphere. In the work, results of the analysis of long-term variations of hourly average projections of the vector of local anisotropy obtained from the URAGAN data during experimental series of 2007-2011 are presented.

  10. Scientific Understanding from Long Term Observations: Insights from the Long Term Ecological Research (LTER) Program

    NASA Astrophysics Data System (ADS)

    Gosz, J.

    2001-12-01

    The network dedicated to Long Term Ecological Research (LTER) in the United States has grown to 24 sites since it was formed in 1980. Long-term research and monitoring are performed on parameters thatare basic to all ecosystems and are required to understand patterns, processes, and relationship to change. Collectively, the sites in the LTER Network provide opportunities to contrast marine, coastal, and continental regions, the full range of climatic gradients existing in North America, and aquatic and terrestrial habitats in a range of ecosystem types. The combination of common core areas and long-term research and monitoring in many habitats have allowed unprecedented abilities to understand and compare complex temporal and spatial dynamics associated with issues like climate change, effects of pollution, biodiversity and landuse. For example, McMurdo Dry Valley in the Antarctic has demonstrated an increase in glacier mass since 1993 which coincides with a period of cooler than normal summers and more than average snowfall. In contrast, the Bonanza Creek and Toolik Lake sites in Alaska have recorded a warming period unprecedented in the past 200 years. Nitrogen deposition effects have been identified through long-term watershed studies on biogeochemical cycles, especially at Coweeta Hydrological Lab, Harvard Forest, and the Hubbard Brook Experimental Forest. In aquatic systems, such as the Northern Temperate Lakes site, long-term data revealed time lags in effects of invaders and disturbance on lake communities. Biological recovery from an effect such as lake acidification was shown to lag behind chemical recovery. The long-term changes documented over 2 decades have been instrumental in influencing management practices in many of the LTER areas. In Puerto Rico, the Luquillo LTER demonstrated that dams obstruct migrations of fish and freshwater shrimp and water abstraction at low flows can completely obliterate downstream migration of juveniles and damage

  11. The neuronal response at extended timescales: long-term correlations without long-term memory

    PubMed Central

    Soudry, Daniel; Meir, Ron

    2014-01-01

    Long term temporal correlations frequently appear at many levels of neural activity. We show that when such correlations appear in isolated neurons, they indicate the existence of slow underlying processes and lead to explicit conditions on the dynamics of these processes. Moreover, although these slow processes can potentially store information for long times, we demonstrate that this does not imply that the neuron possesses a long memory of its input, even if these processes are bidirectionally coupled with neuronal response. We derive these results for a broad class of biophysical neuron models, and then fit a specific model to recent experiments. The model reproduces the experimental results, exhibiting long term (days-long) correlations due to the interaction between slow variables and internal fluctuations. However, its memory of the input decays on a timescale of minutes. We suggest experiments to test these predictions directly. PMID:24744724

  12. The effect of minimum impact education on visitor spatial behavior in parks and protected areas: An experimental investigation using GPS-based tracking.

    PubMed

    Kidd, Abigail M; Monz, Christopher; D'Antonio, Ashley; Manning, Robert E; Reigner, Nathan; Goonan, Kelly A; Jacobi, Charles

    2015-10-01

    The unmanaged impacts of recreation and tourism can often result in unacceptable changes in resource conditions and quality of the visitor experience. Minimum impact visitor education programs aim to reduce the impacts of recreation by altering visitor behaviors. Specifically, education seeks to reduce impacts resulting from lack of knowledge both about the consequences of one's actions and impact-minimizing best practices. In this study, three different on-site minimum impact education strategies ("treatments") and a control condition were applied on the trails and summit area of Sargent Mountain in Acadia National Park, Maine. Treatment conditions were designed to encourage visitors to stay on marked trails and minimize off-trail travel. Treatments included a message delivered via personal contact, and both an ecological-based message and an amenity-based message posted on signs located alongside the trail. A control condition of current trail markings and directional signs was also assessed. The efficacy of the messaging was evaluated through the use of Global Positioning System (GPS) tracking of visitor spatial behavior on/off trails. Spatial analysis of GPS tracks revealed statistically significant differences among treatments, with the personal contact treatment yielding significantly less dispersion of visitors on the mountain summit. Results also indicate that the signs deployed in the study were ineffective at limiting off-trail use beyond what can be accomplished with trail markers and directional signs. These findings suggest that personal contact by a uniformed ranger or volunteer may be the most effective means of message delivery for on-site minimum impact education. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Recommended features of protocols for long-term ecological monitoring

    USGS Publications Warehouse

    Oakley, Karen L.; Boudreau, Susan L.; Humphrey, Sioux-Z

    2001-01-01

    In 1991, the National Park Service (NPS) selected seven parks to serve as prototypes for development of a long-term ecological monitoring program. Denali National Park and Preserve was one of the prototype parks selected. The principal focus of this national program was to detect and document resource changes and to understand the forces driving those changes. One of the major tasks of each prototype park was to develop monitoring protocols. In this paper, we discuss some lessons learned and what we believe to be the most important features of protocols.One of the many lessons we have learned is that monitoring protocols vary greatly in content and format. This variation leads to confusion about what information protocols should contain and how they should be formatted. Problems we have observed in existing protocols include (1) not providing enough detail, (2) omitting critical topics (such as data management), and (3) mixing explanation with instructions. Once written, protocols often sit on the shelf to collect dust, allowing methods changes to occur without being adequately considered, tested, or documented. Because a lengthy and costly research effort is often needed to develop protocols, a vision of what the final product should look like is helpful. Based on our involvement with the prototype monitoring program for Denali (Oakley and Boudreau 2000), we recommend key features of protocols, including a scheme for linking protocols to data in the data management system and for tracking protocol revisions. A protocol system is crucial for producing long-term data sets of known quality that meet program objectives.

  14. Design of microdevices for long-term live cell imaging

    NASA Astrophysics Data System (ADS)

    Chen, Huaying; Rosengarten, Gary; Li, Musen; Nordon, Robert E.

    2012-06-01

    Advances in fluorescent live cell imaging provide high-content information that relates a cell's life events to its ancestors. An important requirement to track clonal growth and development is the retention of motile cells derived from an ancestor within the same microscopic field of view for days to weeks, while recording fluorescence images and controlling the mechanical and biochemical microenvironments that regulate cell growth and differentiation. The aim of this study was to design a microwell device for long-term, time-lapse imaging of motile cells with the specific requirements of (a) inoculating devices with an average of one cell per well and (b) retaining progeny of cells within a single microscopic field of view for extended growth periods. A two-layer PDMS microwell culture device consisting of a parallel-plate flow cell bonded on top of a microwell array was developed for cell capture and clonal culture. Cell deposition statistics were related to microwell geometry (plate separation and well depth) and the Reynolds number. Computational fluid dynamics was used to simulate flow in the microdevices as well as cell-fluid interactions. Analysis of the forces acting upon a cell was used to predict cell docking zones, which were confirmed by experimental observations. Cell-fluid dynamic interactions are important considerations for design of microdevices for long-term, live cell imaging. The analysis of force and torque balance provides a reasonable approximation for cell displacement forces. It is computationally less intensive compared to simulation of cell trajectories, and can be applied to a wide range of microdevice geometries to predict the cell docking behavior.

  15. Modeling Maintenance of Long-Term Potentiation in Clustered Synapses: Long-Term Memory without Bistability

    PubMed Central

    Smolen, Paul

    2015-01-01

    Memories are stored, at least partly, as patterns of strong synapses. Given molecular turnover, how can synapses maintain strong for the years that memories can persist? Some models postulate that biochemical bistability maintains strong synapses. However, bistability should give a bimodal distribution of synaptic strength or weight, whereas current data show unimodal distributions for weights and for a correlated variable, dendritic spine volume. Thus it is important for models to simulate both unimodal distributions and long-term memory persistence. Here a model is developed that connects ongoing, competing processes of synaptic growth and weakening to stochastic processes of receptor insertion and removal in dendritic spines. The model simulates long-term (>1 yr) persistence of groups of strong synapses. A unimodal weight distribution results. For stability of this distribution it proved essential to incorporate resource competition between synapses organized into small clusters. With competition, these clusters are stable for years. These simulations concur with recent data to support the “clustered plasticity hypothesis” which suggests clusters, rather than single synaptic contacts, may be a fundamental unit for storage of long-term memory. The model makes empirical predictions and may provide a framework to investigate mechanisms maintaining the balance between synaptic plasticity and stability of memory. PMID:25945261

  16. Modeling maintenance of long-term potentiation in clustered synapses: long-term memory without bistability.

    PubMed

    Smolen, Paul

    2015-01-01

    Memories are stored, at least partly, as patterns of strong synapses. Given molecular turnover, how can synapses maintain strong for the years that memories can persist? Some models postulate that biochemical bistability maintains strong synapses. However, bistability should give a bimodal distribution of synaptic strength or weight, whereas current data show unimodal distributions for weights and for a correlated variable, dendritic spine volume. Thus it is important for models to simulate both unimodal distributions and long-term memory persistence. Here a model is developed that connects ongoing, competing processes of synaptic growth and weakening to stochastic processes of receptor insertion and removal in dendritic spines. The model simulates long-term (>1 yr) persistence of groups of strong synapses. A unimodal weight distribution results. For stability of this distribution it proved essential to incorporate resource competition between synapses organized into small clusters. With competition, these clusters are stable for years. These simulations concur with recent data to support the "clustered plasticity hypothesis" which suggests clusters, rather than single synaptic contacts, may be a fundamental unit for storage of long-term memory. The model makes empirical predictions and may provide a framework to investigate mechanisms maintaining the balance between synaptic plasticity and stability of memory.

  17. A security/safety survey of long term care facilities.

    PubMed

    Acorn, Jonathan R

    2010-01-01

    What are the major security/safety problems of long term care facilities? What steps are being taken by some facilities to mitigate such problems? Answers to these questions can be found in a survey of IAHSS members involved in long term care security conducted for the IAHSS Long Term Care Security Task Force. The survey, the author points out, focuses primarily on long term care facilities operated by hospitals and health systems. However, he believes, it does accurately reflect the security problems most long term facilities face, and presents valuable information on security systems and practices which should be also considered by independent and chain operated facilities.

  18. LONG TERM IN SITU DISPOSAL ENGINEERING STUDY

    SciTech Connect

    ADAMS; CARLSON; BROCKMAN

    2003-07-23

    Patent application pulled per Ken Norris (FH General Counsel). The objective of this study is to devise methods, produce conceptual designs, examine and select alternatives, and estimate costs for the demonstration of long-term (300-year) in situ disposal of an existing waste disposal site. The demonstration site selected is the 216-A-24 Crib near the 200 East Area. The site contains a fission product inventory and has experienced plant, animal, and inadvertent than intrusion. Of the potential intrusive events and transport pathways at the site, potential human intrusion has been given primary consideration in barrier design. Intrusion by wind, plants, and animals has been given secondary consideration. Groundwater modeling for a number of barrier configurations has been carried out to help select a barrier that will minimize water infiltration and waste/water contact time. The estimated effective lifetime and cost of 20 barrier schemes, using a variety of materials, have been evaluated. The schemes studied include single component surface barriers, multicomponent barriers, and massively injected grout barriers. Five barriers with high estimated effective lifetimes and relatively low costs have been selected for detailed evaluation. They are basalt riprap barriers, massive soil barriers, salt basin barriers, multi-component fine/coarse barriers, and cemented basalt barriers. A variety of materials and configurations for marking the site have also been considered. A decision analysis was completed to select a barrier scheme for demonstration. The analysis indicated that the basalt riprap alternative would be the preferred choice for a full-scale demonstration. The recommended approach is to demonstrate the basalt riprap barrier at the 216-A-24 Crib as soon as possible. Methods and costs of assessing effectiveness of the demonstration are also described. Preliminary design modifications and costs for applying the five selected barrier schemes to other site types are

  19. Long-term Behavior of DNAPL Residuals

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Illangasekare, T.; Kitanidis, P. K.

    2012-12-01

    Understanding and being able to predict the long-term behavior of DNAPL (i.e., TCE) residuals in the source zone are significant in the evaluation of plume spreading. We apply both theoretical analysis and pore-scale simulations to investigate the mass transfer and the effect of reductive dechlorination, in which the contaminant behaves as electron acceptor. At the upfront of the source zone, where the boundary layer has not fully developed, the mass transfer increases as a power-law function of the Peclet number, and is enhanced by biodegradation. These results are consistent with past findings. Under certain conditions, further downstream inside the source zone, the rate of dissolution is slower due to the diluted mass from upstream. Widely applied first-order biodegradation implicitly assumes that the reaction solely depends on the concentration of the contaminant. However, in the slow dilution region, the limitation of electron donor on biodegradation is not negligible. For the reaction between an electron donor and an electron acceptor with intrinsic second-order kinetics, the late-time bio-reaction demonstrates a first-order decay macroscopically with respect to the mass of electron donor, not with respect to that of the contaminant. The late-time decay rate only depends on the intrinsic rate and the solubility of the contaminant. During the intermediate time, affecting by both the concentrations of electron donor and electron acceptor, the first-order decay is not valid. We show that the electron donor decays as exp(-t^2), instead of exp(-t). Moreover, the intermediate-time decay rate is a function of the spatial distribution of DNAPL residuals and the initial conditions.he relationship of the Sherwood number and Peclet number (Comparison of pore-scale simulations and best-fitting curve) he decay of electron donor as a function of t^2

  20. Long term cultivation of larger benthic Foraminifera

    NASA Astrophysics Data System (ADS)

    Wöger, Julia; Eder, Wolfgang; Kinoshita, Shunichi; Antonino, Briguglio; Carles, Ferrandes-Cañadell; Hohenegger, Johann

    2015-04-01

    Benthic Foraminifera are used in a variety of applications employing numerous different methods, i.e. ecological monitoring, studying the effects of ocean acidification, reconstructing palaeo-bathymetry or investigating palaeo-salinity and palaeo-temperature to name only a few. To refine our understanding of ecological influences on larger benthic foraminiferal biology and to review inferences from field observations, culture experiments have become an indispensable tool. While culture experiments on smaller benthic foraminifera have become increasingly frequent in the past century, reports of the cultivation of symbiont bearing larger Foraminifera are rare. Generally, cultivation experiments can be divided into two groups: Culturing of populations and cultivation of single specimens allowing individual investigation. The latter differ form the former by several restrictions resulting from the need to limit individual motility without abridging microenvironmental conditions in the Foraminiferans artificial habitat, necessary to enable the individual to development as unfettered as possible. In this study we present first experiences and preliminary results of the long-term cultivation of larger benthic Foraminifera conducted at the 'Tropical Biosphere Research Station Sesoko Island, University of the Ryukyus', Japan, trying to reproduce natural conditions as closely as possible. Individuals of three species of larger benthic Foraminifera (Heterostegina depressa, Palaeonummulites venosus and Operculina complanata) have been cultured since April 2014. At the time of the general assembly the cultivation experiments will have been going on for more than one year, with the aim to investigate growth rates, longevities and reproduction strategies for comparison with results statistically inferred from application of the of the 'natural laboratory' method. The most important factor influencing foraminiferal health and development was found to be light intensity and light

  1. GPU-optimized Code for Long-term Simulations of Beam-beam Effects in Colliders

    SciTech Connect

    Roblin, Yves; Morozov, Vasiliy; Terzic, Balsa; Aturban, Mohamed A.; Ranjan, D.; Zubair, Mohammed

    2013-06-01

    We report on the development of the new code for long-term simulation of beam-beam effects in particle colliders. The underlying physical model relies on a matrix-based arbitrary-order symplectic particle tracking for beam transport and the Bassetti-Erskine approximation for beam-beam interaction. The computations are accelerated through a parallel implementation on a hybrid GPU/CPU platform. With the new code, a previously computationally prohibitive long-term simulations become tractable. We use the new code to model the proposed medium-energy electron-ion collider (MEIC) at Jefferson Lab.

  2. Long term effects of oral contraception.

    PubMed

    Koetsawang, S; Chiemprasert, T; Premyodhin, M

    1972-01-01

    This study attempts to assess the long-term effects of oral contraceptives on Asian women. At the Family Planning Clinic, Siniray Hospital, Thailand, 181 of the more than 800 women who had used oral contraceptives for more than 4 years prior to May 31, 1971, were studied. All had completed premedical examinations before beginning the drugs. In addition to being studied for changes in body weight, blood pressure, hematocrit, liver function, thyroid function, oral glucose tolerance, and blood urea nitrogen, they were interviewed on their experience with oral contraception. Most were between ages 25-29 years, had only primary education, were housewives, and more than half were in the lower income group. Living children ranged from 1 to 10 with 52.5% having 4 or more. They had been started on a variety or oral contraceptives but in the last 2 years all were given Ovral (norgestrel .5 mg with ethinyl estradiol .05 mg). A total of 10,830 cycles were recorded. Only 9 requested anotehr method. Culdoscopic tubal sterilization was done on 6 and 3 discontinued because they wanted to get pregnant. All had heard rumors of adverse effects but few believed them because 89.3% had no adverse effects. 81.2% said they were in better physical and mental condition because of absence of pregnancy and a majority reported better socioeconomic status. Neurotic complaints were noted in 6.1%. Libido was unchanged in a majority, decreased in a few, but rarely increased. Weight gain of 2.5 kg or more was present in 68%. Slight increase in blood pressure was noted in 17.1%, mostly in those starting with increased pressure. Hematocrit values changed only slightly may have been due to other causes. Liver function tests showed prolonged bromsulphthalein retention in a considerable number. Thyroid function tests were normal except for increased TBG level in 17.8%. Carbohydrate metabolism remained normal in all but a few. Pretreatment glucose tolerance tests not been recorded. Normal findings were

  3. LOP- LONG-TERM ORBIT PREDICTOR

    NASA Technical Reports Server (NTRS)

    Kwok, J. H.

    1994-01-01

    The Long-Term Orbit Predictor (LOP) trajectory propagation program is a useful tool in lifetime analysis of orbiting spacecraft. LOP is suitable for studying planetary orbit missions with reconnaissance (flyby) and exploratory (mapping) trajectories. Sample data is included for a geosynchronous station drift cycle study, a Venus radar mapping strategy, a frozen orbit about Mars, and a repeat ground trace orbit. LOP uses the variation-of-parameters method in formulating the equations of motion. Terms involving the mean anomaly are removed from numerical integrations so that large step sizes, on the order of days, are possible. Consequently, LOP executes much faster than programs based on Cowell's method, such as the companion program ASAP (the Artificial Satellite Analysis Program, NPO-17522, also available through COSMIC). The program uses a force model with a gravity field of up to 21 by 21, lunisolar perturbation, drag, and solar radiation pressure. The input includes classical orbital elements (either mean or oscillating), orbital elements of the sun relative to the planet, reference time and dates, drag coefficients, gravitational constants, planet radius, rotation rate. The printed output contains the classical elements for each time step or event step, and additional orbital data such as true anomaly, eccentric anomaly, latitude, longitude, periapsis altitude, and the rate of change per day of certain elements. Selected output is additionally written to a plot file for postprocessing by the user. LOP is written in FORTRAN 77 for batch execution on IBM PC compatibles running MS-DOS with a minimum of 256K RAM. Recompiling the source requires the Lahey F77 v2.2 compiler. The LOP package includes examples that use LOTUS 1-2-3 for graphical displays, but any graphics software package should be able to handle the ASCII plot file. The program is available on two 5.25 inch 360K MS-DOS format diskettes. The program was written in 1986 and last updated in 1989. LOP is

  4. LOP- LONG-TERM ORBIT PREDICTOR

    NASA Technical Reports Server (NTRS)

    Kwok, J. H.

    1994-01-01

    The Long-Term Orbit Predictor (LOP) trajectory propagation program is a useful tool in lifetime analysis of orbiting spacecraft. LOP is suitable for studying planetary orbit missions with reconnaissance (flyby) and exploratory (mapping) trajectories. Sample data is included for a geosynchronous station drift cycle study, a Venus radar mapping strategy, a frozen orbit about Mars, and a repeat ground trace orbit. LOP uses the variation-of-parameters method in formulating the equations of motion. Terms involving the mean anomaly are removed from numerical integrations so that large step sizes, on the order of days, are possible. Consequently, LOP executes much faster than programs based on Cowell's method, such as the companion program ASAP (the Artificial Satellite Analysis Program, NPO-17522, also available through COSMIC). The program uses a force model with a gravity field of up to 21 by 21, lunisolar perturbation, drag, and solar radiation pressure. The input includes classical orbital elements (either mean or oscillating), orbital elements of the sun relative to the planet, reference time and dates, drag coefficients, gravitational constants, planet radius, rotation rate. The printed output contains the classical elements for each time step or event step, and additional orbital data such as true anomaly, eccentric anomaly, latitude, longitude, periapsis altitude, and the rate of change per day of certain elements. Selected output is additionally written to a plot file for postprocessing by the user. LOP is written in FORTRAN 77 for batch execution on IBM PC compatibles running MS-DOS with a minimum of 256K RAM. Recompiling the source requires the Lahey F77 v2.2 compiler. The LOP package includes examples that use LOTUS 1-2-3 for graphical displays, but any graphics software package should be able to handle the ASCII plot file. The program is available on two 5.25 inch 360K MS-DOS format diskettes. The program was written in 1986 and last updated in 1989. LOP is

  5. Pulmonary complications after long term amiodarone treatment.

    PubMed Central

    Roca, J; Heras, M; Rodriguez-Roisin, R; Magriñà, J; Xaubet, A; Sanz, G

    1992-01-01

    BACKGROUND: Amiodarone hydrochloride is an antiarrhythmic agent useful in arrhythmias refractory to standard therapy. Although interstitial pneumonitis is known to be its most serious side effect, several aspects of amiodarone lung toxicity are still controversial. METHODS: Pulmonary side effects were examined in a sample of 61 symptomless patients (mean (SD) age 55 (7) years) who had had long term treatment with amiodarone (daily maintenance dose 400 mg), selected from 482 men attending the University of Barcelona myocardial infarction project. To allow for the confounding effects of coronary artery disease and tobacco history on lung function, 46 patients who had taken amiodarone for more than one year were matched with a control group from the same population. Subjects underwent measurement of lung volumes, arterial blood gas analysis and an incremental bicycle exercise test. RESULTS: Most lung function values were close to predicted values, though there was a small increase in resting alveolar-arterial oxygen tension difference (A-aDO2) at rest (4.8 (1.4) kPa in both groups). There were no differences in the results of forced spirometry or static lung volumes between the two groups, or in the fall in A-aDO2 from rest to exercise. There was a small difference between the amiodarone and the control group in transfer factor for carbon monoxide corrected for lung volume (KCO 1.67 (0.3) and 1.83 (0.3) mmol min-1 kPa-1 l-1 respectively) and in exercise capacity (140 (25) and 120 (30)w). Only three patients showed lung function impairment consistent with pneumonitis. No relation between lung function measures and cumulative doses of amiodarone or desethylamiodarone was found. CONCLUSIONS: The prevalence of clinically evident pulmonary side effects was 4.9%, which is lower than that reported in studies in which higher daily maintenance doses of amiodarone were given. The slightly lower KCO values and lower work load achieved by the patients taking amiodarone suggest a

  6. Long-Term Space Astrophysics Program

    NASA Technical Reports Server (NTRS)

    Nowark, Michael A.

    2001-01-01

    This is the final report for our Long-Term Space Astrophysics Program (NRA 94-OSS-12) grant NAG 5-3225. The proposal is entitled 'Spectral and Temporal Properties of Black Hole Candidates', and began funding in May 1995, and ran through 31 Aug 2000. The project summary from the original proposal was as follows: 'We will study the spectral and temporal properties of black hole candidates (BHC) by using data from archival sources (e.g., EXOSAT, Ginga, ROSAT) and proposed follow-up observations with modern instruments (e.g., ASCA, XTE). Our spectral studies will focus on identifying the basic characteristics and luminosities of the emission components in the various 'states' of BHC. We hope to understand and quantify the global energetics of these states. Our temporal studies will focus on expanding and classifying our knowledge of BHC variability properties in each state. We will explore the nature of quasi-periodic oscillations in BHC. We will combine our spectral and temporal studies by analyzing time lags and variability coherence between energy channels. In addition, we will investigate ways of correlating observed variability behavior with specific emission components.' We have accomplished many of these goals laid out within the original proposal. As originally proposed, we have utilized both archival and proprietary satellite data. In terms of archival data, we have utilized data from the Advanced Satellite for Cosmology and Astrophysics (ASCA), ROSAT, and the Rossi X-ray Timing Explorer (RXTE). We also obtained proprietary data from ASCA, RXTE, and the Extreme Ultraviolet Explorer (EUVE). In terms of sources, we have examined a wide variety of both galactic black hole candidates and extra-galactic black holes. For the galactic black holes we have observed and analyzed both the low/hard state and the high/soft state. We have performed both spectral and timing analyses on all of these objects. In addition, we have also examined a number of neutron stars or

  7. Integrating different tracking systems in football: multiple camera semi-automatic system, local position measurement and GPS technologies.

    PubMed

    Buchheit, Martin; Allen, Adam; Poon, Tsz Kit; Modonutti, Mattia; Gregson, Warren; Di Salvo, Valter

    2014-12-01

    Abstract During the past decade substantial development of computer-aided tracking technology has occurred. Therefore, we aimed to provide calibration equations to allow the interchangeability of different tracking technologies used in soccer. Eighty-two highly trained soccer players (U14-U17) were monitored during training and one match. Player activity was collected simultaneously with a semi-automatic multiple-camera (Prozone), local position measurement (LPM) technology (Inmotio) and two global positioning systems (GPSports and VX). Data were analysed with respect to three different field dimensions (small, <30 m(2) to full-pitch, match). Variables provided by the systems were compared, and calibration equations (linear regression models) between each system were calculated for each field dimension. Most metrics differed between the 4 systems with the magnitude of the differences dependant on both pitch size and the variable of interest. Trivial-to-small between-system differences in total distance were noted. However, high-intensity running distance (>14.4 km · h(-1)) was slightly-to-moderately greater when tracked with Prozone, and accelerations, small-to-very largely greater with LPM. For most of the equations, the typical error of the estimate was of a moderate magnitude. Interchangeability of the different tracking systems is possible with the provided equations, but care is required given their moderate typical error of the estimate.

  8. Stochastic Induction of Long-Term Potentiation and Long-Term Depression

    PubMed Central

    Antunes, G.; Roque, A. C.; Simoes-de-Souza, F. M.

    2016-01-01

    Long-term depression (LTD) and long-term potentiation (LTP) of granule-Purkinje cell synapses are persistent synaptic alterations induced by high and low rises of the intracellular calcium ion concentration ([Ca2+]), respectively. The occurrence of LTD involves the activation of a positive feedback loop formed by protein kinase C, phospholipase A2, and the extracellular signal-regulated protein kinase pathway, and its expression comprises the reduction of the population of synaptic AMPA receptors. Recently, a stochastic computational model of these signalling processes demonstrated that, in single synapses, LTD is probabilistic and bistable. Here, we expanded this model to simulate LTP, which requires protein phosphatases and the increase in the population of synaptic AMPA receptors. Our results indicated that, in single synapses, while LTD is bistable, LTP is gradual. Ca2+ induced both processes stochastically. The magnitudes of the Ca2+ signals and the states of the signalling network regulated the likelihood of LTP and LTD and defined dynamic macroscopic Ca2+ thresholds for the synaptic modifications in populations of synapses according to an inverse Bienenstock, Cooper and Munro (BCM) rule or a sigmoidal function. In conclusion, our model presents a unifying mechanism that explains the macroscopic properties of LTP and LTD from their dynamics in single synapses. PMID:27485552

  9. Long-term depression of excitatory synaptic transmission and its relationship to long-term potentiation.

    PubMed

    Artola, A; Singer, W

    1993-11-01

    In many brain areas, including the cerebellar cortex, neocortex, hippocampus, striatum and nucleus accumbens, brief activation of an excitatory pathway can produce long-term depression (LTD) of synaptic transmission. In most preparations, induction of LTD has been shown to require a minimum level of postsynaptic depolarization and a rise in the intracellular Ca2+ concentration [Ca2+]i in the postsynaptic neurone. Thus, induction conditions resemble those described for the initiation of associative long-term potentiation (LTP). However, data from structures susceptible to both LTD and LTP suggest that a stronger depolarization and a greater increase in [Ca2+]i are required to induce LTP than to initiate LTD. The source of Ca2+ appears to be less critical for the differential induction of LTP and LTD than the amplitude of the Ca2+ surge, since the activation of voltage- and ligand-gated Ca2+ conductances as well as the release from intracellular stores have all been shown to contribute to both LTD and LTP induction. LTD is induceable even at inactive synapses if [Ca2+]i is raised to the appropriate level by antidromic or heterosynaptic activation, or by raising the extracellular Ca2+ concentration [Ca2+]o. These conditions suggest a rule (called here the ABS rule) for activity-dependent synaptic modifications that differs from the classical Hebb rule and that can account for both homosynaptic LTD and LTP as well as for heterosynaptic competition and associativity.

  10. Visual working memory buffers information retrieved from visual long-term memory.

    PubMed

    Fukuda, Keisuke; Woodman, Geoffrey F

    2017-05-16

    Human memory is thought to consist of long-term storage and short-term storage mechanisms, the latter known as working memory. Although it has long been assumed that information retrieved from long-term memory is represented in working memory, we lack neural evidence for this and need neural measures that allow us to watch this retrieval into working memory unfold with high temporal resolution. Here, we show that human electrophysiology can be used to track information as it is brought back into working memory during retrieval from long-term memory. Specifically, we found that the retrieval of information from long-term memory was limited to just a few simple objects' worth of information at once, and elicited a pattern of neurophysiological activity similar to that observed when people encode new information into working memory. Our findings suggest that working memory is where information is buffered when being retrieved from long-term memory and reconcile current theories of memory retrieval with classic notions about the memory mechanisms involved.

  11. Multi-source energy harvester for wildlife tracking

    NASA Astrophysics Data System (ADS)

    Wu, You; Zuo, Lei; Zhou, Wanlu; Liang, Changwei; McCabe, Michael

    2014-03-01

    Sufficient power supply to run GPS machinery and transmit data on a long-term basis remains to be the key challenge for wildlife tracking technology. Traditional way of replacing battery periodically is not only time and money consuming but also dangerous to live-trapping wild animals. In this paper, an innovative wildlife tracking device with multi-source energy harvester with advantage of high efficiency and reliability is investigated and developed. This multi-source energy harvester entails a solar energy harvester and an innovative rotational electromagnetic energy harvester is mounted on the "wildlife tracking collar" which will remarkably extend the duration of wild life tracking. A feedforward and feedback control of DC-DC converter circuit is adopted to passively realize the Maximum Power Point Tracking (MPPT) logic for the solar energy harvester. The rotational electromagnetic energy harvester can mechanically rectify the irregular bidirectional motion into unidirectional motion has been modeled and demonstrated.

  12. Long-Term Monitoring of Global Climate Forcings and Feedbacks

    NASA Technical Reports Server (NTRS)

    Hansen, J. (Editor); Rossow, W. (Editor); Fung, I. (Editor)

    1993-01-01

    A workshop on Long-Term Monitoring of Global Climate Forcings and Feedbacks was held February 3-4, 1992, at NASA's Goddard Institute for Space Studies to discuss the measurements required to interpret long-term global temperature changes, to critique the proposed contributions of a series of small satellites (Climsat), and to identify needed complementary monitoring. The workshop concluded that long-term (several decades) of continuous monitoring of the major climate forcings and feedbacks is essential for understanding long-term climate change.

  13. Consider long-term care as service alternative.

    PubMed

    Loria, L S

    1987-04-01

    The increasing demand for elderly care services, pressures on inpatient average length of stay and payment levels, and potential financial rewards from providing additional services, makes long-term care look attractive to hospitals. Long-term care, however, is not for every hospital. Before deciding to establish long-term care services, management should examine how the service fits within the hospital's strategic plan. The action plan below provides guidance in evaluating a decision to use hospital facilities for long-term care. Examine how long-term care services fit within the hospital's strategic plan. Study area demographics and competitors to assess the need and supply of long-term care services. Survey the medical staff, consumers and payers to determine attitudes, perceptions and interests regarding long-term care services. Develop a facility plan that identifies areas of excess capacity that can be most easily converted into long-term care with minimal effects on hospital operations. Prepare a financial feasibility analysis of the contribution margin and return on investment attributable to long-term care services. Include an impact analysis on hospital operations. Establish a management task force to develop a detailed implementation plan including assigned individual responsibilities and related timetable. Develop an effective marketing plan designed to generate increased patient market share.

  14. Jason-1 Precise Orbit Determination from GPS Tracking: Method, Performance and Calibration of the Lc Phase Center Offset

    NASA Technical Reports Server (NTRS)

    Luthcke, Scott B.

    2002-01-01

    Jason-1, launched on December 7, 2001, is continuing the time series of centimeter level Ocean topography observations as the follow-on to the highly successful TOPEX/POSEIDON (T/P) radar altimeter satellite. The precision orbit determination (POD) is a critical component to meeting the Ocean topography goals of the mission. T/P has demonstrated that the time variation of Ocean topography can be determined with an accuracy of a few centimeters, thanks to the availability of highly accurate orbits based primarily on SLR+DORIS tracking. The Jason-1 mission is intended to continue measurement of the Ocean surface with the same, if not better accuracy.

  15. A new image for long-term care.

    PubMed

    Wager, Richard; Creelman, William

    2004-04-01

    To counter widely held negative images of long-term care, managers in the industry should implement quality-improvement initiatives that include six key strategies: Manage the expectations of residents and their families. Address customers' concerns early. Build long-term customer satisfaction. Allocate resources to achieve exceptional outcomes in key areas. Respond to adverse events with compassion. Reinforce the facility's credibility.

  16. Long-Term Orientation and Educational Performance. Working Paper 174

    ERIC Educational Resources Information Center

    Figlio, David; Giuliano, Paola; Özek, Umut; Sapienza, Paola

    2017-01-01

    We use remarkable population-level administrative education and birth records from Florida to study the role of Long-Term Orientation on the educational attainment of immigrant students living in the US. Controlling for the quality of schools and individual characteristics, students from countries with long-term oriented attitudes perform better…

  17. Developmental Dyslexia and Explicit Long-Term Memory

    ERIC Educational Resources Information Center

    Menghini, Deny; Carlesimo, Giovanni Augusto; Marotta, Luigi; Finzi, Alessandra; Vicari, Stefano

    2010-01-01

    The reduced verbal long-term memory capacities often reported in dyslexics are generally interpreted as a consequence of their deficit in phonological coding. The present study was aimed at evaluating whether the learning deficit exhibited by dyslexics was restricted only to the verbal component of the long-term memory abilities or also involved…

  18. Long-Term Retention of Electronic Theses and Dissertations.

    ERIC Educational Resources Information Center

    Teper, Thomas H.; Kraemer, Beth

    2002-01-01

    Examines the increasing trend of universities to pursue electronic thesis and dissertation (ETD) programs. Although the goal of most programs is similar, procedural variations impact a program's long-term success. As primary research generators, responsibility for providing long-term access to unique materials must be borne by universities.…

  19. Developmental Dyslexia and Explicit Long-Term Memory

    ERIC Educational Resources Information Center

    Menghini, Deny; Carlesimo, Giovanni Augusto; Marotta, Luigi; Finzi, Alessandra; Vicari, Stefano

    2010-01-01

    The reduced verbal long-term memory capacities often reported in dyslexics are generally interpreted as a consequence of their deficit in phonological coding. The present study was aimed at evaluating whether the learning deficit exhibited by dyslexics was restricted only to the verbal component of the long-term memory abilities or also involved…

  20. Perceptions of control and long-term recovery from rape.

    PubMed

    Regehr, C; Cadell, S; Jansen, K

    1999-01-01

    The relationship between perceptions of control and symptoms of both long-term depression and post-traumatic stress was examined. Enduring beliefs of personal competence and control were found to be associated with lower rates of depression and stress and to be stronger predictors of long-term recovery than were rape-specific attributions. Implications for clinical practice are discussed.

  1. Factors Affecting Long-Term Abstinence from Substances Use

    ERIC Educational Resources Information Center

    Elsheikh, Salah Elgaily

    2008-01-01

    Objective: The purpose of this study is to explore the attitudes of abstainers from drug use that relate to the factors leading to long-term abstinence. Materials and Methods: Cross-sectional study was carried out in Al-Amal Hospital to examine, which attitudes of abstainers related to long-term abstinence. A random survey was conducted on 62…

  2. Adaptive Long-Term Monitoring at Environmental Restoration Sites

    DTIC Science & Technology

    2009-11-01

    bounds value that is a potential concern. .............. 27 Figure 6. Conceptual example to illustrate temporal interpolation issue...Force Base HMSI Hazard Management Systems, Inc. IDW inverse distance weighting LTM long term monitoring LTMO long-term monitoring...provided the best representation of the plumes with Model Builder. • SO provided useful trade-off curves of sampling cost versus the interpolation

  3. Initiating Long-Term Soil Productivity Research in Missouri

    Treesearch

    Felix Ponder

    1997-01-01

    Management practices necessary for sustaining long-term soil productivity (LTSP) afforest lands are being defined from a network of coordinated, long-term experiments established in vartous ecosystems across the United States and British Columbia according to the same basic study plan. The study was established in the Ozark Region of southeastem Missouri in Shannon...

  4. 47 CFR 54.303 - Long term support.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... base-level of Long Term Support for 1998, the Administrator shall calculate the difference between the.... (2) To calculate Long Term Support for calendar year 1998, the Administrator shall adjust the base...; and (4) The line port costs in excess of basic analog service pursuant to § 69.130 of this...

  5. 47 CFR 54.303 - Long term support.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... base-level of Long Term Support for 1998, the Administrator shall calculate the difference between the.... (2) To calculate Long Term Support for calendar year 1998, the Administrator shall adjust the base...; and (4) The line port costs in excess of basic analog service pursuant to § 69.130 of this...

  6. [Developing the core competencies of long-term care professionals].

    PubMed

    Chen, Huey-Tzy; Lee, Kuang-Ting

    2012-12-01

    Longer average life expectancies and an ageing society have made long-term care an urgent and important issue in Taiwan. Although the implementation of Long-Term Care Ten-year Project four years ago has begun showing success in terms of assessing Taiwan's needs in terms of long-term care services and resources, there has been little forward progress in terms of training, recruiting and maintaining more competent professionals in the long-term care sector. This paper explores the current state of long-term care competency in Taiwan and educational strategies in place to improve the competency of long-term care professionals. Results indicate that the term geriatric competency embraces sub-competencies in direct care, communication, assessment, teamwork, cultural sensitivities and career care competencies. The term long-term care competency embraces the sub-competencies of supervision, management, information technology, resource management, and organizational skill. As a main contributor to effective long-term care, the nursing profession must employ effective strategies to develop competency-based education. Also, the profession must have an adequate supply of competent manpower to effectively respond to Taiwan's aging society.

  7. Ensuring climate information guides long-term development

    NASA Astrophysics Data System (ADS)

    Jones, Lindsey; Dougill, Andrew; Jones, Richard G.; Steynor, Anna; Watkiss, Paul; Kane, Cheikh; Koelle, Bettina; Moufouma-Okia, Wilfran; Padgham, Jon; Ranger, Nicola; Roux, Jean-Pierre; Suarez, Pablo; Tanner, Thomas; Vincent, Katharine

    2015-09-01

    Many sub-Saharan countries are failing to include climate information in long-term development planning. Ensuring climate-resilient development requires a step change in how medium- to long-term climate information is produced, communicated and utilized in sub-Saharan Africa and elsewhere.

  8. Short- and Long-Term Consequences of Adolescent Work.

    ERIC Educational Resources Information Center

    Mihalic, Sharon Wofford; Elliott, Delbert

    1997-01-01

    Examines the short- and long-term consequences of working during adolescence. Responses from 1,725 adolescents reveal that the negative short-term effects are in the domains of school, family and friend bonding, beliefs, and substance use. The long-term beneficial effect is that the duration of early work helps employability in adulthood. (GR)

  9. 7 CFR 1773.44 - Long-term debt.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 12 2014-01-01 2013-01-01 true Long-term debt. 1773.44 Section 1773.44 Agriculture... (CONTINUED) POLICY ON AUDITS OF RUS BORROWERS RUS Required Audit Procedures and Documentation § 1773.44 Long-term debt. The CPA's workpapers must document that he/she: (a) Confirmed RUS, FFB, and RTB debt to...

  10. 7 CFR 1773.44 - Long-term debt.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 12 2011-01-01 2011-01-01 false Long-term debt. 1773.44 Section 1773.44 Agriculture... (CONTINUED) POLICY ON AUDITS OF RUS BORROWERS RUS Required Audit Procedures and Documentation § 1773.44 Long-term debt. The CPA's workpapers must document that he/she: (a) Confirmed RUS, FFB, and RTB debt to...

  11. Long Term Agroecosystem Research in the southern plains

    USDA-ARS?s Scientific Manuscript database

    The Southern Plains (SP) site of the Long Term Agroecosystem Research (LTAR) network is headquartered at USDA-ARS’s Grazinglands Research Laboratory (GRL) in El Reno, Oklahoma. The GRL was established in 1948. A long-term watershed and climate research program was established in the Little Washita ...

  12. Long-term forest ecosystem research: a programmatic view

    Treesearch

    Wayne Swank; James Vose

    2010-01-01

    Long-term research provides the building blocks of knowledge needed to address natural resource and environmental issues. "Long-term" has frequently been considered to span decades with a time frame that usually encompasses at least one generation of scientists and frequently two or more generations. In the rich history of forest science, the origin of long-...

  13. The Effect of Modality on Long-Term Recognition Memory.

    ERIC Educational Resources Information Center

    Dean, Raymond S.; And Others

    1988-01-01

    The effects of visual and auditory modes of input on long-term memory were examined in two experiments, each with 40 and 80 undergraduates, respectively. In both experiments, visual stimulus attributes were a more salient dimension than were auditory features in the long-term encoding and retrieval process. (SLD)

  14. Long-Term Dynamics of Autonomous Fractional Differential Equations

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Xu, Wei; Xu, Yong; Han, Qun

    This paper aims to investigate long-term dynamic behaviors of autonomous fractional differential equations with effective numerical method. The long-term dynamic behaviors predict where systems are heading after long-term evolution. We make some modification and transplant cell mapping methods to autonomous fractional differential equations. The mapping time duration of cell mapping is enlarged to deal with the long memory effect. Three illustrative examples, i.e. fractional Lotka-Volterra equation, fractional van der Pol oscillator and fractional Duffing equation, are studied with our revised generalized cell mapping method. We obtain long-term dynamics, such as attractors, basins of attraction, and saddles. Compared with some existing stability and numerical results, the validity of our method is verified. Furthermore, we find that the fractional order has its effect on the long-term dynamics of autonomous fractional differential equations.

  15. Environmental Management Long-Term Stewardship Transition Guidance

    SciTech Connect

    Kristofferson, Keith

    2001-11-01

    Long-term stewardship consists of those actions necessary to maintain and demonstrate continued protection of human health and the environment after the completion of facility cleanup. Long-term stewardship is administered and overseen by the U.S. Department of Energy Environmental Management Office of Science and Technology. This report describes the background of long-term stewardship and gives general guidance about considerations when ownership and/or responsibility of a site should be transferred to a long-term stewardship program. This guidance document will assist the U.S. Department of Energy in: (a) ensuring that the long-term stewardship program leads transition planning with respect to facility and site areas, and (b) describing the classes and types of criteria and data required to initiate transition for areas and sites where the facility mission has ended and cleanup is complete.

  16. A perspective on long-term care for the elderly

    PubMed Central

    Scanlon, William J.

    1988-01-01

    Long-term care represents a significant burden to the approximately 7 million elderly in need, their families, and the Medicaid program. Concerns exist about access, quality, cost, and the distribution of the burden of care. In this article each area is discussed, highlighting the principal issues, identifying the unique aspects that pertain to long-term care, and exploring the implications for research and policy development. Future trends, especially the growth of the elderly population, are expected to affect significantly the provision of long-term care. The considerable uncertainty about how these trends may impact on long-term care is described, and the critical role social choice will play in shaping the future long-term care system is emphasized. PMID:10312975

  17. The relationship between interannual and long-term cloud feedbacks

    SciTech Connect

    Zhou, Chen; Zelinka, Mark D.; Dessler, Andrew E.; Klein, Stephen A.

    2015-12-11

    The analyses of Coupled Model Intercomparison Project phase 5 simulations suggest that climate models with more positive cloud feedback in response to interannual climate fluctuations also have more positive cloud feedback in response to long-term global warming. Ensemble mean vertical profiles of cloud change in response to interannual and long-term surface warming are similar, and the ensemble mean cloud feedback is positive on both timescales. However, the average long-term cloud feedback is smaller than the interannual cloud feedback, likely due to differences in surface warming pattern on the two timescales. Low cloud cover (LCC) change in response to interannual and long-term global surface warming is found to be well correlated across models and explains over half of the covariance between interannual and long-term cloud feedback. In conclusion, the intermodel correlation of LCC across timescales likely results from model-specific sensitivities of LCC to sea surface warming.

  18. [Long-term care insurance in taiwan: theory and challenges].

    PubMed

    Lee, Jwo-Leun; Lung, Chi-Hsuan; Liu, Li-Fan

    2010-08-01

    Long-term care insurance, now being intensively discussed as part of the formal governmental agenda, is widely expected to be inaugurated by 2011. As all entitled citizens will be enrolled compulsorily in accordance with social insurance rules, tight scrutiny in the planning process is strongly advised. Equity of financial mechanisms and the efficiency of the delivery system for long-term care should also be carefully considered and maximized. This study explores major empirical suggestions for Taiwan's long-term care insurance scheme from a primarily theoretical point of view. The three relevant issues deliberated in this paper include risk sharing and financial equity in long-term care insurance and long-term care system delivery efficiency. Content focuses on concepts that may be easily misunderstood or misinterpreted by medical professionals.

  19. The GPS Space Service Volume

    NASA Technical Reports Server (NTRS)

    Bauer, F. H.; Moreau, M. C.; Dahle-Melsaether, M. E.; Petrofski, W. P.; Stanton, B. J.; Thomason, S.; Harris, G. A.; Sena, R. P.; Temple, L. Parker, III

    2006-01-01

    Prior to the advent of artificial satellites, the concept of navigating in space and the desire to understand and validate the laws of planetary and satellite motion dates back centuries. At the initiation of orbital flight in 1957, space navigation was dominated by inertial and groundbased tracking methods, underpinned by the laws of planetary motion. It was early in the 1980s that GPS was first explored as a system useful for refining the position, velocity, and timing (PVT) of other spacecraft equipped with GPS receivers. As a result, an entirely new GPS utility was developed beyond its original purpose of providing PVT services for land, maritime, and air applications. Spacecraft both above and below the GPS constellation now receive the GPS signals, including the signals that spill over the limb of the Earth. The use of radionavigation satellite services for space navigation in High Earth Orbits is in fact a capability unique to GPS. Support to GPS space applications is being studied and planned as an important improvement to GPS. This paper discusses the formalization of PVT services in space as part of an overall GPS improvement effort. It describes the GPS Space Service Volume (SSV) and compares it to the Terrestrial Service Volume (TSV). It also discusses SSV coverage with the current GPS constellation, coverage characteristics as a function of altitude, expected power levels, and coverage figures of merit.

  20. Control of a self guided tracked vehicle for hazardous waste removal using GPS positioning and ultrasonic collision avoidance

    SciTech Connect

    Roy, B.; Lokhorst, D.; Fung, P.; Rice, P.

    1996-12-31

    In 1994 a large hydraulic telerobotic tracked transport vehicle (TTV) was built for Lockheed Idaho Technologies by a team of companies consisting of RAHCO International of Spokane, Spar Aerospace of Toronto and RSI Research of Victoria. The TTV was developed as a part of the Department of Energy`s Buried Waste Integrated Demonstration Program to transport low level transuranic waste in a safe, dust-free manner minimizing the potential spread of airborne contaminants. The TTV was controlled from a remote control station by an operator relying on video and sensor feedback. This paper describes the control system of SGTV, a self guided version of the TTV developed in 1995 to travel autonomously between loading and off-loading points while automatically avoiding obstacles in its path. Self-guidance is divided between a supervisory Mission Planning and Control computer (WC) and an on-board system of five networked computers.

  1. Long-term greenhouse gas measurements from aircraft

    NASA Astrophysics Data System (ADS)

    Karion, A.; Sweeney, C.; Wolter, S.; Newberger, T.; Chen, H.; Andrews, A.; Kofler, J.; Neff, D.; Tans, P.

    2012-10-01

    In March 2009 the NOAA/ESRL/GMD Carbon Cycle and Greenhouse Gases Group collaborated with the US Coast Guard (USCG) to establish the Alaska Coast Guard (ACG) sampling site, a unique addition to NOAA's atmospheric monitoring network. This collaboration takes advantage of USCG bi-weekly Arctic Domain Awareness (ADA) flights, conducted with Hercules C-130 aircraft from March to November each year. NOAA has installed window-replacement inlet plates on two USCG C-130 aircraft and deploys a pallet with NOAA instrumentation on each ADA flight. Flights typically last 8 h and cover a very large area, traveling from Kodiak, AK in the south up to Barrow, AK in the north, and making altitude profiles near the coast as well as in the interior. NOAA instrumentation on each flight includes: a flask sampling system, a continuous CO2/CH4/CO/H2O analyzer, a continuous ozone analyzer, and an ambient temperature and humidity sensor. GPS time and location from the aircraft's navigation system are also collected. Air samples collected in flight are analyzed at NOAA/ESRL for the major greenhouse gases and a variety of halocarbons and hydrocarbons that influence climate, stratospheric ozone, and air quality. Instruments on this aircraft are designed and deployed to be able to collect air samples and data autonomously, so that NOAA personnel visit the site only for installation at the beginning of each season. We present an assessment of the cavity ring-down spectroscopy (CRDS) CO2/CH4/CO/H2O analyzer performance operating on an aircraft over a three-year period. We describe the overall system for making accurate greenhouse gas measurements using a CRDS analyzer on an aircraft with minimal operator interaction. Short and long-term stability of the CRDS analyzer over a seven-month deployment period is better than 0.15 ppm, 2 ppb, and 5 ppb for CO2, CH4, CO respectively, considering differences of on-board reference tank measurements from a laboratory calibration performed prior to

  2. A Demonstration of GPS Landslide Monitoring Using Online Positioning User Service (OPUS)

    NASA Astrophysics Data System (ADS)

    Wang, G.

    2011-12-01

    Global Positioning System (GPS) technologies have been frequently applied to landslide study, both as a complement, and as an alternative to conventional surveying methods. However, most applications of GPS for landslide monitoring have been limited to the academic community for research purposes. High-accuracy GPS has not been widely equipped in geotechnical companies and used by technicians. The main issue that limits the applications of GPS in the practice of high-accuracy landslide monitoring is the complexity of GPS data processing. This study demonstrated an approach using the Online Positioning User Service (OPUS) (http://www.ngs.noaa.gov/OPUS) provided by the National Geodetic Survey (NGS) of National Oceanic and Atmospheric Administration (NOAA) to process GPS data and conduct long-term landslide monitoring in the Puerto Rico and Virgin Islands Region. Continuous GPS data collected at a creeping landslide site during two years were used to evaluate different scenarios for landslide surveying: continuous or campaign, long duration or short duration, morning or afternoon (different weather conditions). OPUS uses Continuously Operating Reference Station (CORS) managed by NGS (http://www.ngs.noaa.giv/CORS/) as references and user data as a rover to solve a position. There are 19 CORS permanent GPS stations in the Puerto Rico and Virgin Islands region. The dense GPS network provides a precise and reliable reference frame for subcentimeter-accuracy landslide monitoring in this region. Our criterion for the accuracy was the root-mean-square (RMS) of OPUS solutions over a 2-year period with respect to true landslide displacement time series overt the same period. The true landslide displacements were derived from a single-baseline (130 m) GPS processing by using 24-hour continuous data. If continuous GPS surveying is performed in the field, then OPUS static processing can provide 0.6 cm horizontal and 1.1 cm vertical precision with few outliers. If repeated

  3. GPS instrumentation for the Trident weapon system

    NASA Astrophysics Data System (ADS)

    Grossman, J.; Jacobson, L.; Wells, L.

    With the planned full operational deployment of the Navstar Global Positioning System (GPS), many applications for the system are beginning to be developed. This paper discusses the concept of GPS instrumentation for the Trident II (D-5) program as well as the background for the Navy's use of existing GPS assets for test evaluation of the Trident I (C-4) Weapon System. Included are the concepts of translated GPS used for real-time tracking for missile range safety as well as for posttest performance evaluation (metric tracking) of the Trident guidance system. The use of GPS pseudosatellite signals to enhance the robustness of the tracking system to provide range safety information is presented. GPS time transfer capabilities are to be used to ensure efficient time synchronization operation for all stations. The unique design features associated with using GPS for range instrumentation are highlighted.

  4. The Womanly World of Long Term Care: The Plight of the Long Term Care Worker. Gray Paper.

    ERIC Educational Resources Information Center

    Older Women's League, Washington, DC.

    Long-term care workers (those who are paid to provide custodial care for long-term patients in nursing homes or at home) must care for a growing number of increasingly disabled or dependent persons. They are working for agencies and institutions under growing pressure to increase productivity. They face new training and competency requirements,…

  5. Abstracts 1987. New Horizons in Long Term Care: A Report on the Long Term Care Research and Demonstration Projects.

    ERIC Educational Resources Information Center

    Illinois State Dept. of Public Aid, Springfield.

    This booklet provides a description of 14 projects which were awarded funds during fiscal year 1987 for collaborative research in long-term care to find new ways to treat long-term care patients in Illinois nursing homes. It includes the organization or institution receiving the award, an abstract of the research proposal, and the name of the…

  6. The Womanly World of Long Term Care: The Plight of the Long Term Care Worker. Gray Paper.

    ERIC Educational Resources Information Center

    Older Women's League, Washington, DC.

    Long-term care workers (those who are paid to provide custodial care for long-term patients in nursing homes or at home) must care for a growing number of increasingly disabled or dependent persons. They are working for agencies and institutions under growing pressure to increase productivity. They face new training and competency requirements,…

  7. Application of the open-source mantle convection code ASPECT to long-term tectonic simulations

    NASA Astrophysics Data System (ADS)

    Naliboff, J.; Brune, S.

    2016-12-01

    The open-source mantle convection code ASPECT (Computational Infrastructure for Geodynamics) provides a robust foundation for numerically examining a wide range of geodynamic processes. ASPECT's strength arises from its massive scalability, use of AMR (adaptive mesh refinement), advanced solvers, community support and modular design, the latter of which permits straightforward modification of discrete components of the code, such as constitutive relationships. Here, we present preliminary work that uses such adaptions to model long-term tectonic problems (lithospheric and upper mantle dynamics) with ASPECT. Crustal- and lithospheric-scale deformation is modeled using a recently implemented visco-plastic constitutive relationship, with viscous flow characterized by diffusion and/or dislocation creep and plastic failure following a Drucker-Prager yield criterion model. Distinct compositional layers and their associated material properties are tracked through field- or tracer-based methods, which also allow tracking of time-dependent properties such as accumulated strain. Preliminary 2-D models of long-term (> 10 Myr) continental extension successfully reproduce results of prior studies with rift basin structure largely dependent on initial lithospheric structure, extension velocity and strain-softening parameterization. Building on these preliminary results, our presentation will focus on ASPECT's viability and performance for modeling long-term tectonics within the context of 2-D vs. 3-D simulations, CPU scaling, distinct solver methods, adaptive mesh refinement and field- vs. tracer-based methods. Our primary goal in addressing these topics is to highlight ASPECT's current functionality and address key areas of future development associated with modeling long-term tectonics. Additionally, we hope to spur discussion regarding a long-term tectonics benchmark that addresses the strong resolution-dependence of simulations using plasticity formulations based on the

  8. Fracture risk assessment in long-term care: a survey of long-term care physicians.

    PubMed

    Wall, Michelle; Lohfeld, Lynne; Giangregorio, Lora; Ioannidis, George; Kennedy, Courtney C; Moser, Andrea; Papaioannou, Alexandra; Morin, Suzanne N

    2013-10-18

    The majority of frail elderly who live in long-term care (LTC) are not treated for osteoporosis despite their high risk for fragility fractures. Clinical Practice Guidelines for the diagnosis and management of osteoporosis provide guidance for the management of individuals 50 years and older at risk for fractures, however, they cannot benefit LTC residents if physicians perceive barriers to their application. Our objectives are to explore current practices to fracture risk assessment by LTC physicians and describe barriers to applying the recently published Osteoporosis Canada practice guidelines for fracture assessment and prevention in LTC. A cross-sectional survey was conducted with the Ontario Long-Term Care Physicians Association using an online questionnaire. The survey included questions that addressed members' attitudes, knowledge, and behaviour with respect to fracture risk assessment in LTC. Closed-ended responses were analyzed using descriptive statistics and thematic framework analysis for open-ended responses. We contacted 347 LTC physicians; 25% submitted completed surveys (81% men, mean age 60 (Standard Deviation [SD] 11) years, average 32 [SD 11] years in practice). Of the surveyed physicians, 87% considered prevention of fragility fractures to be important, but a minority (34%) reported using validated fracture risk assessment tools, while 33% did not use any. Clinical risk factors recommended by the OC guidelines for assessing fracture risk considered applicable included; glucocorticoid use (99%), fall history (93%), age (92%), and fracture history (91%). Recommended clinical measurements considered applicable included: weight (84%), thyroid-stimulating hormone (78%) and creatinine (73%) measurements, height (61%), and Get-Up-and-Go test (60%). Perceived barriers to assessing fracture risk included difficulty acquiring necessary information, lack of access to tests (bone mineral density, x-rays) or obtaining medical history; resource constraints

  9. Long-term use of stimulants in children with attention deficit hyperactivity disorder: safety, efficacy, and long-term outcome.

    PubMed

    Hechtman, Lily; Greenfield, Brian

    2003-01-01

    The purpose of this review is to summarize existing data on the long-term safety and efficacy of stimulant treatment, and how long-term stimulant treatment of children with attention deficit hyperactivity disorder (ADHD) affects their outcome. Existing controlled studies of children with ADHD treated and untreated with stimulants, as well as long-term prospective follow-up studies, are reviewed. Children with ADHD treated with stimulants for as long as 2 years continue to benefit from the treatment, with improvements observed in ADHD symptoms, comorbid oppositional defiant disorder, and academic and social functioning, with no significant problems of tolerance or adverse effects. Long-term, prospective follow-up studies into adulthood show that stimulant treatment in childhood has slight benefits regarding social skills and self-esteem. Long-term adverse effects from stimulant treatment in childhood regarding adult height or future substance abuse have not been supported by existing studies.

  10. Applications of GPS-tracked personal and fixed-location PM(2.5) continuous exposure monitoring.

    PubMed

    Sloan, Chantel D; Philipp, Tyler J; Bradshaw, Rebecca K; Chronister, Sara; Barber, W Bradford; Johnston, James D

    2016-01-01

    Continued development of personal air pollution monitors is rapidly improving government and research capabilities for data collection. In this study, we tested the feasibility of using GPS-enabled personal exposure monitors to collect personal exposure readings and short-term daily PM2.5 measures at 15 fixed locations throughout a community. The goals were to determine the accuracy of fixed-location monitoring for approximating individual exposures compared to a centralized outdoor air pollution monitor, and to test the utility of two different personal monitors, the RTI MicroPEM V3.2 and TSI SidePak AM510. For personal samples, 24-hr mean PM2.5 concentrations were 6.93 μg/m³ (stderr = 0.15) and 8.47 μg/m³ (stderr = 0.10) for the MicroPEM and SidePak, respectively. Based on time-activity patterns from participant journals, exposures were highest while participants were outdoors (MicroPEM = 7.61 µg/m³, stderr = 1.08, SidePak = 11.85 µg/m³, stderr = 0.83) or in restaurants (MicroPEM = 7.48 µg/m³, stderr = 0.39, SidePak = 24.93 µg/m³, stderr = 0.82), and lowest when participants were exercising indoors (MicroPEM = 4.78 µg/m³, stderr = 0.23, SidePak = 5.63 µg/m³, stderr = 0.08). Mean PM(2.5) at the 15 fixed locations, as measured by the SidePak, ranged from 4.71 µg/m³ (stderr = 0.23) to 12.38 µg/m³ (stderr = 0.45). By comparison, mean 24-h PM(2.5) measured at the centralized outdoor monitor ranged from 2.7 to 6.7 µg/m³ during the study period. The range of average PM(2.5) exposure levels estimated for each participant using the interpolated fixed-location data was 2.83 to 19.26 µg/m³ (mean = 8.3, stderr = 1.4). These estimated levels were compared with average exposure from personal samples. The fixed-location monitoring strategy was useful in identifying high air pollution microclimates throughout the county. For 7 of 10 subjects, the fixed-location monitoring strategy more closely approximated individuals' 24-hr breathing zone exposures than

  11. Long-term employment and health inequalities in Canadian communities.

    PubMed

    Safaei, Jalil

    2008-01-01

    This study examines the long-term unemployment rate and various health outcomes across Canadian communities to estimate employment-related health inequalities in these communities. The study uses cross-sectional community-level health data along with data on the long-term employment rate for various communities across Canada to quantify health inequalities among these communities. The health outcomes that are considered in this study include total and disease specific mortality rates; health conditions such as high blood pressure, diabetes, injuries, and self rated health; and life expectancies at birth and at age 65. Health inequalities are estimated using the concentration index, which is used to measure health inequalities along socioeconomic dimensions. The concentration index is estimated by a regression of weighted relative health (ill health) over weighted cumulative relative rank of the populations. All the estimates are provided separately for males and females. The findings of the study support the existence of inequalities in community health outcomes as related to the long-term employment rates in those communities. Communities with lower long term employment rates (higher unemployment rates) have poorer health outcomes in terms of higher mortality rates, worse health conditions, and shorter life expectancies. Health inequalities related to long-term employment have important policy implications. They call for policies that would increase and maintain long term employment rates as part of a broader socioeconomic approach to health. Long term employment ensures income security and prevents the psychosocial experiences leading to mental and physical ill health.

  12. Long-Term Stewardship Baseline Report and Transition Guidance

    SciTech Connect

    Kristofferson, Keith

    2001-11-01

    Long-term stewardship consists of those actions necessary to maintain and demonstrate continued protection of human health and the environment after facility cleanup is complete. As the Department of Energy’s (DOE) lead laboratory for environmental management programs, the Idaho National Engineering and Environmental Laboratory (INEEL) administers DOE’s long-term stewardship science and technology efforts. The INEEL provides DOE with technical, and scientific expertise needed to oversee its long-term environmental management obligations complexwide. Long-term stewardship is administered and overseen by the Environmental Management Office of Science and Technology. The INEEL Long-Term Stewardship Program is currently developing the management structures and plans to complete INEEL-specific, long-term stewardship obligations. This guidance document (1) assists in ensuring that the program leads transition planning for the INEEL with respect to facility and site areas and (2) describes the classes and types of criteria and data required to initiate transition for areas and sites where the facility mission has ended and cleanup is complete. Additionally, this document summarizes current information on INEEL facilities, structures, and release sites likely to enter long-term stewardship at the completion of DOE’s cleanup mission. This document is not intended to function as a discrete checklist or local procedure to determine readiness to transition. It is an overarching document meant as guidance in implementing specific transition procedures. Several documents formed the foundation upon which this guidance was developed. Principal among these documents was the Long-Term Stewardship Draft Technical Baseline; A Report to Congress on Long-Term Stewardship, Volumes I and II; Infrastructure Long-Range Plan; Comprehensive Facility Land Use Plan; INEEL End-State Plan; and INEEL Institutional Plan.

  13. Space ventures and society long-term perspectives

    NASA Technical Reports Server (NTRS)

    Brown, W. M.

    1985-01-01

    A futuristic evaluation of mankind's potential long term future in space is presented. Progress in space will not be inhibited by shortages of the Earth's physical resources, since long term economic growth will be focused on ways to constrain industrial productivity by changing social values, management styles, or government competence. Future technological progress is likely to accelerate with an emphasis on international cooperation, making possible such large joint projects as lunar colonies or space stations on Mars. The long term future in space looks exceedingly bright even in relatively pessimistic scenarios. The principal driving forces will be technological progress, commercial and public-oriented satellites, space industrialization, space travel, and eventually space colonization.

  14. Medical care evaluation studies in long-term care facilities.

    PubMed

    Zimmer, J G

    1979-02-01

    This report describes the selection, design, conduct, analysis, and application of medical care evaluation studies in long-term care facilities (skilled nursing homes) in a regional program in the Rochester region of upstate New York. Eight examples are presented to highlight methodologic approaches and problems. They are classified under four general headings: Administration Audits, Diagnosis-specific Studies, Care Modality-specific Studies, and General Outcome Indicators. The implementation of results and recommendations from the studies is discussed and an application of "tracer" methodology for assessing the components of care activities in long-term facilities is described. Problems and challenges in long-term quality care are outlined.

  15. Long-term correlations in the surface behavior of dolphins

    NASA Astrophysics Data System (ADS)

    Cancho, R. Ferrer i.; Lusseau, D.

    2006-06-01

    Here we study the sequences of surface behavioral patterns of dolphins (Tursiops sp.) and find long-term correlations. We show that the long-term correlations are not of a trivial nature, i.e. they cannot be explained by the repetition of the same surface behavior many times in a row. Our findings suggest that dolphins have a long collective memory extending back at least to the 7-th past behavior. As far as we know, this is the first evidence of long-term correlations in the behavior of a non-human species.

  16. Genetic testing for Alzheimer's and long-term care insurance.

    PubMed

    Taylor, Donald H; Cook-Deegan, Robert M; Hiraki, Susan; Roberts, J Scott; Blazer, Dan G; Green, Robert C

    2010-01-01

    A genetic marker known as apolipoprotein E provides a clear signal of a person's risk of developing Alzheimer's disease and thus that person's future need for long-term care. People who find that they have the variant of the trait that increases Alzheimer's disease risk are more likely to purchase long-term care insurance after receiving this information. If the information is widely introduced into the insurance market, coverage rates could be affected in different ways, depending on who possesses that information. Policymakers will eventually need to confront the issue of the use of this and other markers in the pricing of long-term care insurance.

  17. Improving the accuracy of estimates of animal path and travel distance using GPS drift-corrected dead reckoning.

    PubMed

    Dewhirst, Oliver P; Evans, Hannah K; Roskilly, Kyle; Harvey, Richard J; Hubel, Tatjana Y; Wilson, Alan M

    2016-09-01

    Route taken and distance travelled are important parameters for studies of animal locomotion. They are often measured using a collar equipped with GPS. Collar weight restrictions limit battery size, which leads to a compromise between collar operating life and GPS fix rate. In studies that rely on linear interpolation between intermittent GPS fixes, path tortuosity will often lead to inaccurate path and distance travelled estimates. Here, we investigate whether GPS-corrected dead reckoning can improve the accuracy of localization and distance travelled estimates while maximizing collar operating life. Custom-built tracking collars were deployed on nine freely exercising domestic dogs to collect high fix rate GPS data. Simulations were carried out to measure the extent to which combining accelerometer-based speed and magnetometer heading estimates (dead reckoning) with low fix rate GPS drift correction could improve the accuracy of path and distance travelled estimates. In our study, median 2-dimensional root-mean-squared (2D-RMS) position error was between 158 and 463 m (median path length 16.43 km) and distance travelled was underestimated by between 30% and 64% when a GPS position fix was taken every 5 min. Dead reckoning with GPS drift correction (1 GPS fix every 5 min) reduced 2D-RMS position error to between 15 and 38 m and distance travelled to between an underestimation of 2% and an overestimation of 5%. Achieving this accuracy from GPS alone would require approximately 12 fixes every minute and result in a battery life of approximately 11 days; dead reckoning reduces the number of fixes required, enabling a collar life of approximately 10 months. Our results are generally applicable to GPS-based tracking studies of quadrupedal animals and could be applied to studies of energetics, behavioral ecology, and locomotion. This low-cost approach overcomes the limitation of low fix rate GPS and enables the long-term deployment of lightweight GPS collars.

  18. Using GPS and activity tracking to reveal the influence of adolescents' food environment exposure on junk food purchasing.

    PubMed

    Sadler, Richard C; Clark, Andrew F; Wilk, Piotr; O'Connor, Colleen; Gilliland, Jason A

    2016-06-09

    This study examines the influence of adolescents' exposure to unhealthy food outlets on junk food purchasing during trips between home and school, with particular attention to how exposure and purchasing differ according to child's biological sex, mode of transportation, and direction to or from school. Between 2010 and 2013, students (n = 654) aged 9-13 years from 25 schools in London and Middlesex County, ON, completed a socio-demographic survey and an activity diary (to identify food purchases), and were observed via a global positioning system for 2 weeks (to track routes for trips to/from school). Spatial data on routes and purchase data were integrated with a validated food outlet database in a geographic information system, and exposure was measured as the minutes a child spent within 50 m of an unhealthy food outlet (i.e., fast food restaurants, variety stores). For trips involving junk food exposure (n = 4588), multilevel logistic regression was used to assess the relationship between exposure and purchasing. Multilevel analyses indicated that adolescents' duration of exposure to unhealthy food outlets between home and school had a significant effect on the likelihood of junk food purchasing. This relationship remained significant when the data were stratified by sex (female/male), trip direction (to/from school) and travel mode (active/car), with the exception of adolescents who travelled by bus. Policies and programs that mitigate the concentration of unhealthy food outlets close to schools are critical for encouraging healthy eating behaviours among children and reducing diet-related health issues such as obesity.

  19. Predicting patterns of long-term adaptation and extinction with population genetics.

    PubMed

    Bertram, J; Gomez, K; Masel, J

    2017-02-01

    Population genetics struggles to model extinction; standard models track the relative rather than absolute fitness of genotypes, while the exceptions describe only the short-term transition from imminent doom to evolutionary rescue. But extinction can result from failure to adapt not only to catastrophes, but also to a backlog of environmental challenges. We model long-term adaptation to long series of small challenges, where fitter populations reach higher population sizes. The population's long-term fitness dynamic is well approximated by a simple stochastic Markov chain model. Long-term persistence occurs when the rate of adaptation exceeds the rate of environmental deterioration for some genotypes. Long-term persistence times are consistent with typical fossil species persistence times of several million years. Immediately preceding extinction, fitness declines rapidly, appearing as though a catastrophe disrupted a stably established population, even though gradual evolutionary processes are responsible. New populations go through an establishment phase where, despite being demographically viable, their extinction risk is elevated. Should the population survive long enough, extinction risk later becomes constant over time. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  20. Equity of access under Korean national long-term care insurance: implications for long-term care reform.

    PubMed

    Park, Ju Moon

    2015-09-15

    The national long-term care insurance was implemented in July 2008. Few studies have been conducted with representative national survey data since the long-term care insurance was introduced. Therefore, this study examines the extent to which equity in the use of long-term care has been achieved in Korea. The Aday-Andersen model was used as a conceptual model, based on the Korean Health Panel Study which was conducted in 2011. Descriptive and logistic regression analysis was performed to examine the relationship between the dependent and independent variables and the relative importance of factors as predictors of utilization. The results of this study indicated that those who rated his or her health to be fair, good, and very good, had no limited activities, were disabled, and had insurance coverage were more likely to use long-term care services, respectively. Their decision to use long-term care was primarily affected by need (health status, limited activity, disability) and enabling (insurance coverage) factors. The findings also indicated that the introduction of a national long-term care insurance program did not yield a fully equitable distribution of services. Long-term care reforms in Korea should continue to concentrate on expanding insurance coverage and reducing the inequities reflected in disparities in consumer cost-sharing and associated patterns of utilization across plans. The subsequent impact on managed care and expenditures need to be more fully understood.