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Sample records for high rate events

  1. Measuring target detection performance in paradigms with high event rates.

    PubMed

    Bendixen, Alexandra; Andersen, Søren K

    2013-05-01

    Combining behavioral and neurophysiological measurements inevitably implies mutual constraints, such as when the neurophysiological measurement requires fast-paced stimulus presentation and hence the attribution of a behavioral response to a particular preceding stimulus becomes ambiguous. We develop and test a method for validly assessing behavioral detection performance in spite of this ambiguity. We examine four approaches taken in the literature to treat such situations. We analytically derive a new variant of computing the classical parameters of signal detection theory, hit and false alarm rates, adapted to fast-paced paradigms. Each of the previous approaches shows specific shortcomings (susceptibility towards response window choice, biased estimates of behavioral detection performance). Superior performance of our new approach is demonstrated for both simulated and empirical behavioral data. Further evidence is provided by reliable correspondence between behavioral performance and the N2b component as an electrophysiological indicator of target detection. The appropriateness of our approach is substantiated by both theoretical and empirical arguments. We demonstrate an easy-to-implement solution for measuring target detection performance independent of the rate of event presentation. Thus overcoming the measurement bias of previous approaches, our method will help to clarify the behavioral relevance of different measures of cortical activation. Copyright © 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  2. High frame-rate neutron radiography of dynamic events

    NASA Astrophysics Data System (ADS)

    Bossi, R. H.; Robinson, A. H.; Barton, J. P.

    1981-11-01

    A system was developed to perform neutron radiographic analysis of dynamic events having a duration of several milliseconds. The system is operated in the range of 2000 to 10,000 frames/second. Synchronization provided high speed motion neutron radiographs for evaluation of the firing cycle of 7.62 mm munition rounds within a steel rifle barrel. The system was also used to demonstrate the ability to produce neutron radiographic movies of two phase flow. The equipment uses the Oregon State University TRIGA reactor capable of pulsing to 3000 MW peak power, a neutron beam collimator, a scintillator neutron conversion screen coupled to an image intensifier, and a 16 mm high speed movie camera. The peak neutron flux incident at the object position is approximately 4 x 10 to the 11th power n/sq cm with a pulse full width at half maximum, of 9 ms. The scintillator conversion screens and on the effects of statistical limitations on the image quality were studied and modulation transfer function analysis was used to assist in the evaluation of the system performance.

  3. Extragalactic High-energy Transients: Event Rate Densities and Luminosity Functions

    NASA Astrophysics Data System (ADS)

    Sun, Hui; Zhang, Bing; Li, Zhuo

    2015-10-01

    Several types of extragalactic high-energy transients have been discovered, which include high-luminosity and low-luminosity long-duration gamma-ray bursts (GRBs), short-duration GRBs, supernova shock breakouts (SBOs), and tidal disruption events (TDEs) without or with an associated relativistic jet. In this paper, we apply a unified method to systematically study the redshift-dependent event rate densities and the global luminosity functions (GLFs; ignoring redshift evolution) of these transients. We introduce some empirical formulae for the redshift-dependent event rate densities for different types of transients and derive the local specific event rate density, which also represents its GLF. Long GRBs (LGRBs) have a large enough sample to reveal features in the GLF, which is best charaterized as a triple power law (PL). All the other transients are consistent with having a single-power-law (SPL) LF. The total event rate density depends on the minimum luminosity, and we obtain the following values in units of Gpc-3 yr-1: {0.8}-0.1+0.1 for high-luminosity LGRBs above 1050 erg s-1 {164}-65+98 for low-luminosity LGRBs above 5 × 1046 erg s-1 {1.3}-0.3+0.4, {1.2}-0.3+0.4, and {3.3}-0.8+1.0 above 1050 erg s-1 for short GRBs with three different merger delay models (Gaussian, lognormal, and PL); {1.9}-1.2+2.4× {10}4 above 1044 erg s-1 for SBOs, {4.8}-2.1+3.2× {10}2 for normal TDEs above 1044 erg s-1 and {0.03}-0.02+0.04 above 1048 erg s-1 for TDE jets as discovered by Swift. Intriguingly, the GLFs of different kinds of transients, which cover over 12 orders of magnitude, are consistent with an SPL with an index of -1.6.

  4. Extra-galactic high-energy transients: event rate density and luminosity function

    NASA Astrophysics Data System (ADS)

    Sun, Hui; Zhang, Bing; Li, Zhuo

    2015-08-01

    Several types of extra-galactic high-energy transients have been discovered, which include high-luminosity and low-luminosity long-duration gamma-ray bursts (GRBs), short-duration GRBs, supernova shock breakouts (SBOs), and tidal disruption events (TDEs) without or with a relativistic jet. In this paper, we apply a unified method to systematically study the reshift-dependent event rate densities and luminosity functions of these extra-galactic high-energy transients. We consider star formation history as the tracer of the redshift distribution for long GRBs and SBOs. For short GRBs, we consider the compact star merger model to introduce several possible merger delay time distribution models. For TDEs, we consider the mass distribution of supermassive black holes as a function of redshift. We derive some empirical formulae for the redshift-dependent event rate density for different types of transients. Based on the observed events, we derive the local specific event rate density, ρ0,L ∝ dρ0/dL for each type of transient, which represents its luminosity function. All the transients are consistent with having a single power law luminosity function, except the high luminosity long GRBs (HL-lGRBs), whose luminosity function can be well described by a broken power law. The total event rate density for a particular transient depends on the luminosity threshold, and we obtain the following values in units of Gpc-3 yr-1: 2.82^{+0.41}_{-0.36} for HL-lGRBs above 4×1049 erg s-1 218^{+130}_{-86} for low luminosity long GRBs above 6×1046 erg s-1 3.18^{+0.88}_{-0.70}, 2.87^{+0.80}_{-0.64}, and 6.25^{+1.73}_{-1.38} above 5×1049 erg s-1 for short GRBs with three different merger delay models (Gaussian, log-normal, and power law); 2.0^{+2.6}_{-1.3}×104 above 9×1043 erg s-1 for SBOs, 3.0^{+1.0}_{-0.8}×105 for normal TDEs above 1042 erg s-1 and 6.2^{+8.2}_{-4.0} above 3×1047 erg s-1for TDE jets as discovered by Swift. Intriguingly, the global specific event rate densities

  5. A video event trigger for high frame rate, high resolution video technology

    NASA Technical Reports Server (NTRS)

    Williams, Glenn L.

    1991-01-01

    When video replaces film the digitized video data accumulates very rapidly, leading to a difficult and costly data storage problem. One solution exists for cases when the video images represent continuously repetitive 'static scenes' containing negligible activity, occasionally interrupted by short events of interest. Minutes or hours of redundant video frames can be ignored, and not stored, until activity begins. A new, highly parallel digital state machine generates a digital trigger signal at the onset of a video event. High capacity random access memory storage coupled with newly available fuzzy logic devices permits the monitoring of a video image stream for long term or short term changes caused by spatial translation, dilation, appearance, disappearance, or color change in a video object. Pretrigger and post-trigger storage techniques are then adaptable for archiving the digital stream from only the significant video images.

  6. Characterization of an ultraviolet imaging detector with high event rate ROIC (HEROIC) readout

    NASA Astrophysics Data System (ADS)

    Nell, Nicholas; France, Kevin; Harwit, Alex; Bradley, Scott; Franka, Steve; Freymiller, Ed; Ebbets, Dennis

    2016-07-01

    We present characterization results from a photon counting imaging detector consisting of one microchannel plate (MCP) and an array of two readout integrated circuits (ROIC) that record photon position. The ROICs used in the position readout are the high event rate ROIC (HEROIC) devices designed to handle event rates up to 1 MHz per pixel, recently developed by the Ball Aerospace and Technologies Corporation in collaboration with the University of Colorado. An opaque cesium iodide (CsI) photocathode sensitive in the far-ultraviolet (FUV; 122-200 nm), is deposited on the upper surface of the MCP. The detector is characterized in a chamber developed by CU Boulder that is capable of illumination with vacuum-ultraviolet (VUV) monochromatic light and measurement of absolute ux with a calibrated photodiode. Testing includes investigation of the effects of adjustment of internal settings of the HEROIC devices including charge threshold, gain, and amplifier bias. The detector response to high count rates is tested. We report initial results including background, uniformity, and quantum detection efficiency (QDE) as a function of wavelength.

  7. High cardiovascular event rates occur within the first weeks of starting hemodialysis

    PubMed Central

    Eckardt, Kai-Uwe; Gillespie, Iain A; Kronenberg, Florian; Richards, Sharon; Stenvinkel, Peter; Anker, Stefan D; Wheeler, David C; de Francisco, Angel L; Marcelli, Daniele; Froissart, Marc; Floege, Jürgen; Aljama, P; Anker, S; Drueke, T B; Eckardt, K -U; Floege, J; de Francisco, A; Kronenberg, F; Macdougall, I C; Malyszko, J; Schernthaner, G; Stenvinkel, P; Wheeler, D C; Molemans, B; Canaud, B

    2015-01-01

    Early mortality is high in hemodialysis (HD) patients, but little is known about early cardiovascular event (CVE) rates after HD initiation. To study this we analyzed data in the AROii cohort of incident HD patients from over 300 European Fresenius Medical Care dialysis centers. Weekly rates of a composite of CVEs during the first year and monthly rates of the composite and its constituents (coronary artery, cerebrovascular, peripheral arterial, congestive heart failure, and sudden cardiac death) during the first 2 years after HD initiation were assessed. Of 6308 patients that started dialysis within 7 days, 1449 patients experienced 2405 CVEs over the next 2 years. The first-year CVE rate (30.2/100 person-years; 95% CI, 28.7–31.7) greatly exceeded the second-year rate (19.4/100; 95% CI, 18.1–20.8). Composite CVEs were highest during the first week with increased risk compared with the second year, persisting until the fifth month. Except for sudden cardiac death, temporal patterns of rates for all CVE categories were very similar, with highest rates during the first month and a high-risk period extending to 4 months. Higher or lower cumulative weekly dialysis dose, lower blood flow, and lower net ultrafiltration during dialysis were associated with CVE during the high-risk period, but not during the post high-risk period. Thus, the incidence of CVE in the first weeks after HD initiation is much higher than during subsequent periods which raises concerns that HD initiation may trigger CVEs. PMID:25923984

  8. High cardiovascular event rates occur within the first weeks of starting hemodialysis.

    PubMed

    Eckardt, Kai-Uwe; Gillespie, Iain A; Kronenberg, Florian; Richards, Sharon; Stenvinkel, Peter; Anker, Stefan D; Wheeler, David C; de Francisco, Angel L; Marcelli, Daniele; Froissart, Marc; Floege, Jürgen

    2015-11-01

    Early mortality is high in hemodialysis (HD) patients, but little is known about early cardiovascular event (CVE) rates after HD initiation. To study this we analyzed data in the AROii cohort of incident HD patients from over 300 European Fresenius Medical Care dialysis centers. Weekly rates of a composite of CVEs during the first year and monthly rates of the composite and its constituents (coronary artery, cerebrovascular, peripheral arterial, congestive heart failure, and sudden cardiac death) during the first 2 years after HD initiation were assessed. Of 6308 patients that started dialysis within 7 days, 1449 patients experienced 2405 CVEs over the next 2 years. The first-year CVE rate (30.2/100 person-years; 95% CI, 28.7-31.7) greatly exceeded the second-year rate (19.4/100; 95% CI, 18.1-20.8). Composite CVEs were highest during the first week with increased risk compared with the second year, persisting until the fifth month. Except for sudden cardiac death, temporal patterns of rates for all CVE categories were very similar, with highest rates during the first month and a high-risk period extending to 4 months. Higher or lower cumulative weekly dialysis dose, lower blood flow, and lower net ultrafiltration during dialysis were associated with CVE during the high-risk period, but not during the post high-risk period. Thus, the incidence of CVE in the first weeks after HD initiation is much higher than during subsequent periods which raises concerns that HD initiation may trigger CVEs.

  9. High event rate ROICs (HEROICs) for astronomical UV photon counting detectors

    NASA Astrophysics Data System (ADS)

    Harwit, Alex; France, Kevin; Argabright, Vic; Franka, Steve; Freymiller, Ed; Ebbets, Dennis

    2014-07-01

    The next generation of astronomical photocathode / microchannel plate based UV photon counting detectors will overcome existing count rate limitations by replacing the anode arrays and external cabled electronics with anode arrays integrated into imaging Read Out Integrated Circuits (ROICs). We have fabricated a High Event Rate ROIC (HEROIC) consisting of a 32 by 32 array of 55 μm square pixels on a 60 μm pitch. The pixel sensitivity (threshold) has been designed to be globally programmable between 1 × 103 and 1 × 106 electrons. To achieve the sensitivity of 1 × 103 electrons, parasitic capacitances had to be minimized and this was achieved by fabricating the ROIC in a 65 nm CMOS process. The ROIC has been designed to support pixel counts up to 4096 events per integration period at rates up to 1 MHz per pixel. Integration time periods can be controlled via an external signal with a time resolution of less than 1 microsecond enabling temporally resolved imaging and spectroscopy of astronomical sources. An electrical injection port is provided to verify functionality and performance of each ROIC prior to vacuum integration with a photocathode and microchannel plate amplifier. Test results on the first ROICs using the electrical injection port demonstrate sensitivities between 3 × 103 and 4 × 105 electrons are achieved. A number of fixes are identified for a re-spin of this ROIC.

  10. High dose rates obtained outside ISS in June 2015 during SEP event

    NASA Astrophysics Data System (ADS)

    Dachev, T. P.; Tomov, B. T.; Matviichuk, Yu. N.; Dimitrov, Pl. G.; Bankov, N. G.

    2016-06-01

    The R3DR2 instrument performed measurements in the European Space Agency (ESA) EXPOSE-R2 platform outside the Russian "Zvezda" module of the International Space Station (ISS) in the period 24 October 2014-11 January 2016. It is the Liulin-type deposited energy spectrometer (DES) (Dachev et al., 2015a). Took place in November 2014, this was the first attempt to monitor a small solar energetic particle (SEP) event outside ISS using the Liulin-type DES (Dachev et al., 2015d). In this study, we describe the dosimetric characteristics of the largest SEP event, observed on 22 June 2015 with the R3DR2 instrument outside ISS. The main finding of this study is that SEP protons with a minimum energy of approximately 7 MeV at the surface of the R3DR2 detector produced high dose rates, reaching >5000 μGy h-1, while the inner radiation belt maximum dose was at the level of 2200 μGy h-1. If a virtual external vehicle activity (EVA) was performed in the same period of the SEP maximum on 22 June 2015, the doses obtained in the skin of cosmonauts/astronauts can reach 2.84 mGy after 6.5 h, which is similar to the average absorbed dose inside ISS for 15 days (Reitz et al., 2005). A comparison with other extreme events measured with Liulin-type instruments shows that SEPs similar to that observed on 22 June 2015 could be one of the most dangerous events for the cosmonauts/astronauts involved in EVA.

  11. High dose rates obtained outside ISS in June 2015 during SEP event.

    PubMed

    Dachev, T P; Tomov, B T; Matviichuk, Yu N; Dimitrov, Pl G; Bankov, N G

    2016-06-01

    The R3DR2 instrument performed measurements in the European Space Agency (ESA) EXPOSE-R2 platform outside the Russian "Zvezda" module of the International Space Station (ISS) in the period 24 October 2014-11 January 2016. It is the Liulin-type deposited energy spectrometer (DES) (Dachev et al., 2015a). Took place in November 2014, this was the first attempt to monitor a small solar energetic particle (SEP) event outside ISS using the Liulin-type DES (Dachev et al., 2015d). In this study, we describe the dosimetric characteristics of the largest SEP event, observed on 22 June 2015 with the R3DR2 instrument outside ISS. The main finding of this study is that SEP protons with a minimum energy of approximately 7MeV at the surface of the R3DR2 detector produced high dose rates, reaching >5000µGyh(-1), while the inner radiation belt maximum dose was at the level of 2200µGyh(-1). If a virtual external vehicle activity (EVA) was performed in the same period of the SEP maximum on 22 June 2015, the doses obtained in the skin of cosmonauts/astronauts can reach 2.84mGy after 6.5h, which is similar to the average absorbed dose inside ISS for 15days (Reitz et al., 2005). A comparison with other extreme events measured with Liulin-type instruments shows that SEPs similar to that observed on 22 June 2015 could be one of the most dangerous events for the cosmonauts/astronauts involved in EVA. Copyright © 2016 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

  12. Ion-ion coincidence imaging at high event rate using an in-vacuum pixel detector

    NASA Astrophysics Data System (ADS)

    Long, Jingming; Furch, Federico J.; Durá, Judith; Tremsin, Anton S.; Vallerga, John; Schulz, Claus Peter; Rouzée, Arnaud; Vrakking, Marc J. J.

    2017-07-01

    A new ion-ion coincidence imaging spectrometer based on a pixelated complementary metal-oxide-semiconductor detector has been developed for the investigation of molecular ionization and fragmentation processes in strong laser fields. Used as a part of a velocity map imaging spectrometer, the detection system is comprised of a set of microchannel plates and a Timepix detector. A fast time-to-digital converter (TDC) is used to enhance the ion time-of-flight resolution by correlating timestamps registered separately by the Timepix detector and the TDC. In addition, sub-pixel spatial resolution (<6 μm) is achieved by the use of a center-of-mass centroiding algorithm. This performance is achieved while retaining a high event rate (104 per s). The spectrometer was characterized and used in a proof-of-principle experiment on strong field dissociative double ionization of carbon dioxide molecules (CO2), using a 400 kHz repetition rate laser system. The experimental results demonstrate that the spectrometer can detect multiple ions in coincidence, making it a valuable tool for studying the fragmentation dynamics of molecules in strong laser fields.

  13. High energy neutrinos from gamma ray bursts: Event rates in neutrino telescopes

    NASA Astrophysics Data System (ADS)

    Alvarez-Muñiz, J.; Halzen, F.; Hooper, D. W.

    2000-11-01

    Following Waxman and Bahcall we calculate the event rate, energy and zenith angle dependence of neutrinos produced in the fireball model of gamma ray bursts (GRB). We emphasize the primary importance of (i) burst-to-burst fluctuations and (ii) absorption of the neutrinos in the Earth. From the astronomical point of view, we draw attention to the sensitivity of neutrino measurements to the boost Lorentz factor of the fireball Γ, which is central to the fireball model, and only indirectly determined by follow-up observations. Fluctuations result in single bursts emitting multiple neutrinos, making it possible to determine the flavor composition of a beam observed after a baseline of thousands of megaparsecs.

  14. Elliptical Accretion and Low Luminosity from High Accretion Rate Stellar Tidal Disruption Events

    NASA Astrophysics Data System (ADS)

    Svirski, Gilad; Piran, Tsvi; Krolik, Julian

    2017-05-01

    Models for tidal disruption events (TDEs) in which a supermassive black hole disrupts a star commonly assume that the highly eccentric streams of bound stellar debris promptly form a circular accretion disc at the pericentre scale. However, the bolometric peak luminosity of most TDE candidates, ˜ 1044 erg s- 1, implies that we observe only ˜1 per cent of the energy expected from radiatively efficient accretion. Even the energy that must be lost to circularize the returning tidal flow is larger than the observed energy. Recently, Piran et al. suggested that the observed optical TDE emission is powered by shocks at the apocentre between freshly infalling material and earlier arriving matter. This model explains the small radiated energy, the low temperature and the large radius implied by the observations as well as the t-5/3 light curve. However the question of the system's low bolometric efficiency remains unanswered. We suggest that the high orbital energy and low angular momentum of the flow make it possible for magnetic stresses to reduce the matter's already small angular momentum to the point at which it can fall ballistically into the supermassive black hole before circularization. As a result, the efficiency is only ˜1-10 per cent of a standard accretion disc's efficiency. Thus, the intrinsically high eccentricity of the tidal debris naturally explains why most TDE candidates are fainter than expected.

  15. Elliptical Accretion and Low Luminosity from High Accretion Rate Stellar Tidal Disruption Events

    NASA Astrophysics Data System (ADS)

    Svirski, Gilad; Piran, Tsvi; Krolik, Julian

    2017-01-01

    Models for tidal disruption events (TDEs) in which a supermassive black hole disrupts a star commonly assume that the highly eccentric streams of bound stellar debris promptly form a circular accretion disk at the pericenter scale. However, the bolometric peak luminosity of most TDE candidates, ˜ 10^{44} {erg s^{-1}}, implies that we observe only ˜1% of the energy expected from radiatively efficient accretion. Even the energy that must be lost to circularize the returning tidal flow is larger than the observed energy. Recently, Piran et al. (2015) suggested that the observed optical TDE emission is powered by shocks at the apocenter between freshly infalling material and earlier arriving matter. This model explains the small radiated energy, the low temperature, and the large radius implied by the observations as well as the t-5/3 light curve. However the question of the system's low bolometric efficiency remains unanswered. We suggest that the high orbital energy and low angular momentum of the flow make it possible for magnetic stresses to reduce the matter's already small angular momentum to the point at which it can fall ballistically into the SMBH before circularization. As a result, the efficiency is only ˜1-10% of a standard accretion disk's efficiency. Thus, the intrinsically high eccentricity of the tidal debris naturally explains why most TDE candidates are fainter than expected.

  16. Short period airglow temperature and emission rate oscillations in the high Arctic MLT region during stratospheric warming events

    NASA Astrophysics Data System (ADS)

    Lederman, J. I.

    2015-12-01

    The airglow is a photochemical glow in the upper atmosphere that occurs in thin layers corresponding to different chemical processes. The O2 Atmospheric airglow layer exists at about 94 km altitude and the hydroxyl layer at about 87 km. The intensity of the light gives information about the concentration of atomic oxygen there, while the shape of the spectrum gives accurate values of the temperature. In this investigation, these are measured above Eureka in the Canadian Arctic (80N, 86W) using an instrument called SATI (Spectral Airglow Temperature Imager). The optical data are employed to characterize short period oscillations in rotational temperatures and integral emission rates of OH (6,2) Meinel and O2 (0,1) Atm. bands during a stratospheric warming event from January 2015. In this presentation, SATI observations coupled with wind radiosonde data at Eureka and the ECMWF model are used to compare the January 2015 warming with the major stratospheric warming event of January 2009, thereby providing a window into high frequency atmospheric wave dynamics at play between altitudes of 20 km - 100 km.

  17. Optimisation and Validation of the ARAMIS Digital Image Correlation System for Use in Large-scale High-strain-rate Events

    DTIC Science & Technology

    2013-08-01

    strain-rate synergistic blast and fragmentation event. The ARAMIS system uses 3D digital photogrammetry to track surface deformation of an object...high-speed photogrammetry . These issues included adequate lighting conditions, the use of mirrors, large stand-off distances, speckle pattern...Ackermann, F. (1984) Digital Image Correlation: Performance and Potential Application in Photogrammetry . The Photogrammetric Record 11 (64) pp 429-439 2

  18. Combination of High Rate, Real-time GNSS and Accelerometer Observations - Preliminary Results Using a Shake Table and Historic Earthquake Events.

    NASA Astrophysics Data System (ADS)

    Jackson, Michael; Passmore, Paul; Zimakov, Leonid; Raczka, Jared

    2014-05-01

    One of the fundamental requirements of an Earthquake Early Warning (EEW) system (and other mission critical applications) is to quickly detect and process the information from the strong motion event, i.e. event detection and location, magnitude estimation, and the peak ground motion estimation at the defined targeted site, thus allowing the civil protection authorities to provide pre-programmed emergency response actions: Slow down or stop rapid transit trains and high-speed trains; shutoff of gas pipelines and chemical facilities; stop elevators at the nearest floor; send alarms to hospitals, schools and other civil institutions. An important question associated with the EEW system is: can we measure displacements in real time with sufficient accuracy? Scientific GNSS networks are moving towards a model of real-time data acquisition, storage integrity, and real-time position and displacement calculations. This new paradigm allows the integration of real-time, high-rate GNSS displacement information with acceleration and velocity data to create very high-rate displacement records. The mating of these two instruments allows the creation of a new, very high-rate (200 Hz) displacement observable that has the full-scale displacement characteristics of GNSS and high-precision dynamic motions of seismic technologies. It is envisioned that these new observables can be used for earthquake early warning studies and other mission critical applications, such as volcano monitoring, building, bridge and dam monitoring systems. REF TEK a Division of Trimble has developed the integrated GNSS/Accelerograph system, model 160-09SG, which consists of REF TEK's fourth generation electronics, a 147-01 high-resolution ANSS Class A accelerometer, and Trimble GNSS receiver and antenna capable of real time, on board Precise Point Positioning (PPP) techniques with satellite clock and orbit corrections delivered to the receiver directly via L-band satellite communications. The test we

  19. SeismoGeodesy: Combination of High Rate, Real-time GNSS and Accelerometer Observations and Rapid Seismic Event Notification for Earth Quake Early Warning and Volcano Monitoring

    NASA Astrophysics Data System (ADS)

    Jackson, Michael; Zimakov, Leonid; Moessmer, Matthias

    2015-04-01

    Scientific GNSS networks are moving towards a model of real-time data acquisition, epoch-by-epoch storage integrity, and on-board real-time position and displacement calculations. This new paradigm allows the integration of real-time, high-rate GNSS displacement information with acceleration and velocity data to create very high-rate displacement records. The mating of these two instruments allows the creation of a new, very high-rate (200 Hz) displacement observable that has the full-scale displacement characteristics of GNSS and high-precision dynamic motions of seismic technologies. It is envisioned that these new observables can be used for earthquake early warning studies, volcano monitoring, and critical infrastructure monitoring applications. Our presentation will focus on the characteristics of GNSS, seismic, and strong motion sensors in high dynamic environments, including historic earthquakes replicated on a shake table over a range of displacements and frequencies. We will explore the optimum integration of these sensors from a filtering perspective including simple harmonic impulses over varying frequencies and amplitudes and under the dynamic conditions of various earthquake scenarios. We will also explore the tradeoffs between various GNSS processing schemes including real-time precise point positioning (PPP) and real-time kinematic (RTK) as applied to seismogeodesy. In addition we will discuss implementation of a Rapid Seismic Event Notification System that provides quick delivery of digital data from seismic stations to the acquisition and processing center and a full data integrity model for real-time earthquake notification that provides warning prior to significant ground shaking.

  20. Consequence of a sudden wind event on the dynamics of a coastal phytoplankton community: an insight into specific population growth rates using a single cell high frequency approach

    PubMed Central

    Dugenne, Mathilde; Thyssen, Melilotus; Nerini, David; Mante, Claude; Poggiale, Jean-Christophe; Garcia, Nicole; Garcia, Fabrice; Grégori, Gérald J.

    2014-01-01

    Phytoplankton is a key component in marine ecosystems. It is responsible for most of the marine primary production, particularly in eutrophic lagoons, where it frequently blooms. Because they are very sensitive to their environment, the dynamics of these microbial communities has to be observed over different time scales, however, assessment of short term variability is often out of reach of traditional monitoring methods. To overcome these limitations, we set up a Cytosense automated flow cytometer (Cytobuoy b.v.), designed for high frequency monitoring of phytoplankton composition, abundance, cell size, and pigment content, in one of the largest Mediterranean lagoons, the Berre lagoon (South-Eastern France). During October 2011, it recorded the cell optical properties of 12 groups of pico-, nano-, and microphytoplankton. Daily variations in the cluster optical properties were consistent with individual changes observed using microscopic imaging, during the cell cycle. We therefore used an adaptation of the size-structured matrix population model, developed by Sosik et al. (2003) to process the single cell analysis of the clusters and estimate the division rates of 2 dinoflagellate populations before, during, and after a strong wind event. The increase in the estimated in situ daily cluster growth rates suggest that physiological changes in the cells can prevail over the response of abundance. PMID:25309523

  1. Performance of a Micro-Strip Gas Chamber for event wise, high rate thermal neutron detection with accurate 2D position determination

    NASA Astrophysics Data System (ADS)

    Mindur, B.; Alimov, S.; Fiutowski, T.; Schulz, C.; Wilpert, T.

    2014-12-01

    A two-dimensional (2D) position sensitive detector for neutron scattering applications based on low-pressure gas amplification and micro-strip technology was built and tested with an innovative readout electronics and data acquisition system. This detector contains a thin solid neutron converter and was developed for time- and thus wavelength-resolved neutron detection in single-event counting mode, which improves the image contrast in comparison with integrating detectors. The prototype detector of a Micro-Strip Gas Chamber (MSGC) was built with a solid natGd/CsI thermal neutron converter for spatial resolutions of about 100 μm and counting rates up to 107 neutrons/s. For attaining very high spatial resolutions and counting rates via micro-strip readout with centre-of-gravity evaluation of the signal amplitude distributions, a fast, channel-wise, self-triggering ASIC was developed. The front-end chips (MSGCROCs), which are very first signal processing components, are read out into powerful ADC-FPGA boards for on-line data processing and thereafter via Gigabit Ethernet link into the data receiving PC. The workstation PC is controlled by a modular, high performance dedicated software suite. Such a fast and accurate system is crucial for efficient radiography/tomography, diffraction or imaging applications based on high flux thermal neutron beam. In this paper a brief description of the detector concept with its operation principles, readout electronics requirements and design together with the signals processing stages performed in hardware and software are presented. In more detail the neutron test beam conditions and measurement results are reported. The focus of this paper is on the system integration, two dimensional spatial resolution, the time resolution of the readout system and the imaging capabilities of the overall setup. The detection efficiency of the detector prototype is estimated as well.

  2. Public High School Four-Year On-Time Graduation Rates and Event Dropout Rates: School Years 2010-11 and 2011-12. First Look. NCES 2014-391

    ERIC Educational Resources Information Center

    Stetser, Marie C.; Stillwell, Robert

    2014-01-01

    This National Center for Education Statistics (NCES) First Look report introduces new data for two separate measures of 4-year on-time graduation rates as well as event dropout rates for school year (SY) 2010-11 and SY 2011-12. Specifically this report provides the following: (1) Four-year adjusted cohort graduation rate (ACGR) data reported by…

  3. High rates of venous thromboembolic events in patients undergoing systemic therapy for urothelial carcinoma: A systematic review and meta-analysis.

    PubMed

    Gopalakrishna, Ajay; Longo, Thomas A; Fantony, Joseph J; Doshi, Uma; Harrison, Michael R; Van Noord, Megan; Inman, Brant A

    2016-09-01

    Patients undergoing systemic therapy for urothelial carcinoma (UC) are at increased risk for venous thromboembolic (VTE) events. The objective of the current study was to determine the rate of VTE events in patients undergoing systemic therapy for UC and assess factors affecting this rate. This study was registered with the PROSPERO database (CRD42015025774). We searched Pubmed, MEDLINE, EMBASE, The Cochrane Library, CINAHL, and Web of Science libraries through August 2014. As per PRISMA guidelines, 2 reviewers independently reviewed titles and abstracts. Disagreements were arbitrated by a third reviewer. After full text review, data were abstracted and pooled using a random effects model. Authors were contacted for clarification of data. To determine VTE risk factors, subgroup analyses and meta-regression were conducted. We identified 3,635 publications in the initial search, of which 410 met inclusion criteria for full text review. Of these, we were able to obtain data on the outcome of interest for 62 publications. A total of 5,082 patients, of which 77% were male, underwent systemic therapy for UC, with 373 VTE events. The proportion of patients who had had prior surgery, chemotherapy, or radiation was 55%, 25%, and 9%, respectively. Fixed effects and random effects models were used to estimate the VTE rate, yielding event rates of 6.7% and 5.4%, respectively. VTE occurs frequently in patients undergoing systemic therapy for UC. The VTE rate was affected by the country of origin, history of radiation, as well as by the systemic treatment class. The study was limited by the incomplete reporting of all variables of interest. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. THE PRODUCTION RATE OF SN Ia EVENTS IN GLOBULAR CLUSTERS

    SciTech Connect

    Washabaugh, Pearce C.; Bregman, Joel N. E-mail: jbregman@umich.edu

    2013-01-01

    In globular clusters, dynamical evolution produces luminous X-ray emitting binaries at a rate about 200 times greater than in the field. If globular clusters also produce SN Ia at a high rate, it would account for many of the SN Ia production in early-type galaxies and provide insight into their formation. Here we use archival Hubble Space Telescope (HST) images of nearby galaxies that have hosted an SN Ia to examine the rate at which globular clusters produce these events. The location of the SN Ia is registered on an HST image obtained before the event or after the supernova (SN) faded. Of the 36 nearby galaxies examined, 21 had sufficiently good data to search for globular cluster hosts. None of the 21 SNe have a definite globular cluster counterpart, although there are some ambiguous cases. This places an upper limit to the enhancement rate of SN Ia production in globular clusters of about 42 at the 95% confidence level, which is an order of magnitude lower than the enhancement rate for luminous X-ray binaries. Even if all of the ambiguous cases are considered as having a globular cluster counterpart, the upper bound for the enhancement rate is 82 at the 95% confidence level, still a factor of several below that needed to account for half of the SN Ia events. Barring unforeseen selection effects, we conclude that globular clusters are not responsible for producing a significant fraction of the SN Ia events in early-type galaxies.

  5. Pressure-strain-rate events in homogeneous turbulent shear flow

    NASA Technical Reports Server (NTRS)

    Brasseur, James G.; Lee, Moon J.

    1988-01-01

    A detailed study of the intercomponent energy transfer processes by the pressure-strain-rate in homogeneous turbulent shear flow is presented. Probability density functions (pdf's) and contour plots of the rapid and slow pressure-strain-rate show that the energy transfer processes are extremely peaky, with high-magnitude events dominating low-magnitude fluctuations, as reflected by very high flatness factors of the pressure-strain-rate. A concept of the energy transfer class was applied to investigate details of the direction as well as magnitude of the energy transfer processes. In incompressible flow, six disjoint energy transfer classes exist. Examination of contours in instantaneous fields, pdf's and weighted pdf's of the pressure-strain-rate indicates that in the low magnitude regions all six classes play an important role, but in the high magnitude regions four classes of transfer processes, dominate. The contribution to the average slow pressure-strain-rate from the high magnitude fluctuations is only 50 percent or less. The relative significance of high and low magnitude transfer events is discussed.

  6. High event rate after a first percutaneous coronary intervention in patients with diabetes mellitus: results from the Swedish coronary angiography and angioplasty registry.

    PubMed

    Ritsinger, Viveca; Saleh, Nawsad; Lagerqvist, Bo; Norhammar, Anna

    2015-06-01

    Patients with diabetes mellitus have reduced longevity after acute coronary syndromes and revascularization. However, knowledge of the long-term complication rates and patterns from an everyday life setting is lacking. Consecutive patients undergoing percutaneous coronary intervention included in the Swedish Coronary Angiography Angioplasty Registry (SCAAR) between 2006 and 2010 and with no previous revascularization were prospectively followed up for combined cardiovascular events (first of all-cause mortality, myocardial infarction, stroke, and heart failure) until December 31, 2010. The mean follow-up period was 920 days (SD, 530 days). Differences in background and procedural characteristics were adjusted for in a multivariate Cox regression model. Of 58 891 patients, mean age 67 years, 19% had diabetes mellitus; 27% of them were on diet treatment, 33% on oral glucose lowering, and 40% on insulin treatment. At admission, cardiovascular risk factors, multiple coronary vessel, and left main stem disease were more frequent in patients with diabetes mellitus and their revascularization was less often complete. The adjusted risk for combined cardiovascular events was higher in patients on insulin (hazard ratio [95% confidence interval], 1.63 [1.55-1.72]), on oral treatment (1.23 [1.15-1.31]), and on diet alone (1.21 [1.12-1.29]) compared with patients without diabetes mellitus. Insulin-treated patients ran an increased risk of restenosis (1.54 [1.39-1.71]) and stent thrombosis (1.56 [1.25-1.96]). The prognosis after a first percutaneous coronary intervention is more severe in patients with diabetes mellitus, in particular, in patients treated with insulin, with higher rates of mortality, cardiovascular events, and stent thrombosis over the following 5 years. © 2015 American Heart Association, Inc.

  7. High population increase rates.

    PubMed

    1991-09-01

    In addition to its economic and ethnic difficulties, the USSR faces several pressing demographic problems, including high population increase rates in several of its constituent republics. It has now become clear that although the country's rigid centralized planning succeeded in covering the basic needs of people, it did not lead to welfare growth. Since the 1970s, the Soviet economy has remained sluggish, which as led to increase in the death and birth rates. Furthermore, the ideology that held that demography could be entirely controlled by the country's political and economic system is contradicted by current Soviet reality, which shows that religion and ethnicity also play a significant role in demographic dynamics. Currently, Soviet republics fall under 2 categories--areas with high or low natural population increase rates. Republics with low rates consist of Christian populations (Armenia, Moldavia, Georgia, Byelorussia, Russia, Lithuania, Estonia, Latvia, Ukraine), while republics with high rates are Muslim (Tadzhikistan, Uzbekistan, Turkmenistan, Kirgizia, Azerbaijan Kazakhstan). The later group has natural increase rates as high as 3.3%. Although the USSR as a whole is not considered a developing country, the later group of republics fit the description of the UNFPA's priority list. Another serious demographic issue facing the USSR is its extremely high rate of abortion. This is especially true in the republics of low birth rates, where up to 60% of all pregnancies are terminated by induced abortions. Up to 1/5 of the USSR's annual health care budget is spent on clinical abortions -- money which could be better spent on the production of contraceptives. Along with the recent political and economic changes, the USSR is now eager to deal with its demographic problems.

  8. Coastal landslide material loss rates associated with severe climatic events

    USGS Publications Warehouse

    Hapke, C.J.; Green, K.R.

    2006-01-01

    Deep-seated landslides along the California coast deliver large amounts of material to the nearshore littoral environment. Landslide movement, a combined result of slope base undercutting by waves and ground saturation, is highly episodic. Movement occurs primarily during periods of high rainfall and large waves, such as those associated with El Nin??o events. This analysis applies remote-sensing techniques to quantify the volumetric net loss rates at three specific landslide sites along the Big Sur coast over three approximately decadal time periods, two of which contained the largest El Nin??o events of the twentieth century. High-resolution historical terrain models were compared in order to provide surface-elevation change data for each landslide complex. To determine the material influx to the littoral system, the landslide complexes were divided into upper and lower slopes, and the surface-elevation change was converted to a volume loss. Some material lost from the upper slope was deposited at the slope base, not into the littoral system. We describe a method to calculate the net loss that omits the deposition volumes from the upper slope. Loss rates were found to be substantially higher during the periods in which El Nin??o events occurred. This is especially true during the period of the 1997-1998 El Nin??o, when 75% of the total material volume was lost, and loss rates were much as sixteen times higher than during non-El Nin??o periods. ?? 2006 Geological Society of America.

  9. Cross section dependence of event rates at neutrino telescopes.

    PubMed

    Hussain, S; Marfatia, D; McKay, D W; Seckel, D

    2006-10-20

    We examine the dependence of event rates at neutrino telescopes on the neutrino-nucleon cross section for neutrinos with energy above 1 PeV, and contrast the results with those for cosmic ray experiments. Scaling of the standard model cross sections leaves the rate of upward events essentially unchanged. Details, such as detector depth and cross section inelasticity, can influence rates. Numerical estimates of upward shower, muon, and tau event rates in the IceCube detector confirm these results.

  10. FRB Event Rate Predictions for the Ooty Wide Field Array

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, Siddhartha; Bera, Apurba; Bharadwaj, Somnath; Ramesh Bhat, N. D.; Chengalur, Jayaram N.

    2017-03-01

    We developed a generic formalism to estimate the event rate and the redshift distribution of Fast Radio Bursts (FRBs) in our previous publication (Bera et al. 2016), considering FRBs are of an extragalactic origin. In this paper, we present (a) the predicted pulse widths of FRBs by considering two different scattering models, (b) the minimum total energy required to detect events, (c) the redshift distribution and (d) the detection rates of FRBs for the Ooty Wide Field Array (OWFA). The energy spectrum of FRBs is modelled as a power law with an exponent - α and our analysis spans a range -3≤ α≤5. We find that OWFA will be capable of detecting FRBs with α≥0. The redshift distribution and the event rates of FRBs are estimated by assuming two different energy distribution functions; a Delta function and a Schechter luminosity function with an exponent -2≤ γ≤2. We consider an empirical scattering model based on pulsar observations (model I) as well as a theoretical model (model II) expected for the intergalactic medium. The redshift distributions peak at a particular redshift z p for a fixed value of α, which lie in the range 0.3≤ z p ≤1 for the scattering model I and remain flat and extend up to high redshifts ( z≲5) for the scattering model II.

  11. Events per person-time (incidence rate): a misleading statistic?

    PubMed

    Kraemer, Helena Chmura

    2009-03-15

    Results in risk studies based on events per person-time (EPT, technically 'incidence rate') often prove non-confirmable. The circumstances in which the EPT-ratio is unquestionably both valid and optimal to compare a high- and low-risk group, a constant hazards situation, are discussed. However, the constant hazards situation seldom applies in medical research. When the constant hazards situation does not apply, even under optimal circumstances, with fixed entry time and follow-up time for all those not experiencing the event and absence of censoring, EPT-ratio yields at best ambiguous, at worst misleading, results. More careful design and survival analyses are recommended in place of use of EPTs.

  12. A semiparametric additive rates model for recurrent event data.

    PubMed

    Schaubel, Douglas E; Zeng, Donglin; Cai, Jianwen

    2006-12-01

    Recurrent event data often arise in biomedical studies, with examples including hospitalizations, infections, and treatment failures. In observational studies, it is often of interest to estimate the effects of covariates on the marginal recurrent event rate. The majority of existing rate regression methods assume multiplicative covariate effects. We propose a semiparametric model for the marginal recurrent event rate, wherein the covariates are assumed to add to the unspecified baseline rate. Covariate effects are summarized by rate differences, meaning that the absolute effect on the rate function can be determined from the regression coefficient alone. We describe modifications of the proposed method to accommodate a terminating event (e.g., death). Proposed estimators of the regression parameters and baseline rate are shown to be consistent and asymptotically Gaussian. Simulation studies demonstrate that the asymptotic approximations are accurate in finite samples. The proposed methods are applied to a state-wide kidney transplant data set.

  13. Possible high magnification microlensing event

    NASA Astrophysics Data System (ADS)

    Udalski, Andrzej; Szymanski, Michal

    1998-05-01

    The OGLE team informs about a microlensing event in progress - OGLE-1998-BUL-15 (18:07:20.83, -27:34:10.8, J2000) which is presently about 4 days before maximum and is rising rapidly (already more than 2 mag above the normal level). Preliminary fit to the light curve predicts possible maximum magnification as large as 10 mag and maximum on JD=2450945.2. Follow up observations, both photometric and spectroscopic, are strongly encouraged.

  14. Possibly high amplification microlensing event

    NASA Astrophysics Data System (ADS)

    Szymanski, Michal; Udalski, Andrzej

    1998-06-01

    The OGLE team informs about a microlensing event in progress - OGLE-1998-BUL-18 (17:54:21.79, -29:53:24.0, J2000) which is presently about 2 days before maximum. It is relatively bright star (I0=15.5), rising rapidly. Preliminary microlensing fit to the light curve predicts large maximum magnification to be reached on JD=2450971.831 (1998-06-07.33 UT) Follow-up observations, both photometric and spectroscopic, are strongly encouraged.

  15. A fast data acquisition system for the study of transient events by high repetition rate time-of-flight mass spectrometry

    NASA Technical Reports Server (NTRS)

    Lincoln, K. A.; Bechtel, R. D.

    1986-01-01

    Recent advances in commercially available data acquisition electronics embodying high speed A/D conversion coupled to increased memory storage have now made practical (at least within time intervals of a third of a millisecond or more) the capturing of all of the data generated by a high repetition rate time-of-flight mass spectrometer producing complete spectra every 25 to 35 microseconds. Such a system was assembled and interfaced with a personal computer for control and management of data. The applications are described for recording time-resolved spectra of individual vapor plumes induced from the pulsed-laser heating of material. Each laser pulse triggers the system to generate automatically a 3-dimensional (3-D) presentation of the time-resolved spectra with m/z labeling of the major mass peaks, plus an intensity versus time display of both the laser pulse and the resulting vapor pulse. The software also permits storing of data and its presentation in various additional forms.

  16. High Data Rate Quantum Cryptography

    NASA Astrophysics Data System (ADS)

    Kwiat, Paul; Christensen, Bradley; McCusker, Kevin; Kumor, Daniel; Gauthier, Daniel

    2015-05-01

    While quantum key distribution (QKD) systems are now commercially available, the data rate is a limiting factor for some desired applications (e.g., secure video transmission). Most QKD systems receive at most a single random bit per detection event, causing the data rate to be limited by the saturation of the single-photon detectors. Recent experiments have begun to explore using larger degree of freedoms, i.e., temporal or spatial qubits, to optimize the data rate. Here, we continue this exploration using entanglement in multiple degrees of freedom. That is, we use simultaneous temporal and polarization entanglement to reach up to 8.3 bits of randomness per coincident detection. Due to current technology, we are unable to fully secure the temporal degree of freedom against all possible future attacks; however, by assuming a technologically-limited eavesdropper, we are able to obtain 23.4 MB/s secure key rate across an optical table, after error reconciliation and privacy amplification. In this talk, we will describe our high-rate QKD experiment, with a short discussion on our work towards extending this system to ship-to-ship and ship-to-shore communication, aiming to secure the temporal degree of freedom and to implement a 30-km free-space link over a marine environment.

  17. A Framework for Collaborative Review of Candidate Events in High Data Rate Streams: the V-Fastr Experiment as a Case Study

    NASA Astrophysics Data System (ADS)

    Hart, Andrew F.; Cinquini, Luca; Khudikyan, Shakeh E.; Thompson, David R.; Mattmann, Chris A.; Wagstaff, Kiri; Lazio, Joseph; Jones, Dayton

    2015-01-01

    “Fast radio transients” are defined here as bright millisecond pulses of radio-frequency energy. These short-duration pulses can be produced by known objects such as pulsars or potentially by more exotic objects such as evaporating black holes. The identification and verification of such an event would be of great scientific value. This is one major goal of the Very Long Baseline Array (VLBA) Fast Transient Experiment (V-FASTR), a software-based detection system installed at the VLBA. V-FASTR uses a “commensal” (piggy-back) approach, analyzing all array data continually during routine VLBA observations and identifying candidate fast transient events. Raw data can be stored from a buffer memory, which enables a comprehensive off-line analysis. This is invaluable for validating the astrophysical origin of any detection. Candidates discovered by the automatic system must be reviewed each day by analysts to identify any promising signals that warrant a more in-depth investigation. To support the timely analysis of fast transient detection candidates by V-FASTR scientists, we have developed a metadata-driven, collaborative candidate review framework. The framework consists of a software pipeline for metadata processing composed of both open source software components and project-specific code written expressly to extract and catalog metadata from the incoming V-FASTR data products, and a web-based data portal that facilitates browsing and inspection of the available metadata for candidate events extracted from the VLBA radio data.

  18. A framework for collaborative review of candidate events in high data rate streams: The V-FASTR experiment as a case study

    SciTech Connect

    Hart, Andrew F.; Cinquini, Luca; Khudikyan, Shakeh E.; Thompson, David R.; Mattmann, Chris A.; Wagstaff, Kiri; Lazio, Joseph; Jones, Dayton

    2015-01-01

    “Fast radio transients” are defined here as bright millisecond pulses of radio-frequency energy. These short-duration pulses can be produced by known objects such as pulsars or potentially by more exotic objects such as evaporating black holes. The identification and verification of such an event would be of great scientific value. This is one major goal of the Very Long Baseline Array (VLBA) Fast Transient Experiment (V-FASTR), a software-based detection system installed at the VLBA. V-FASTR uses a “commensal” (piggy-back) approach, analyzing all array data continually during routine VLBA observations and identifying candidate fast transient events. Raw data can be stored from a buffer memory, which enables a comprehensive off-line analysis. This is invaluable for validating the astrophysical origin of any detection. Candidates discovered by the automatic system must be reviewed each day by analysts to identify any promising signals that warrant a more in-depth investigation. To support the timely analysis of fast transient detection candidates by V-FASTR scientists, we have developed a metadata-driven, collaborative candidate review framework. The framework consists of a software pipeline for metadata processing composed of both open source software components and project-specific code written expressly to extract and catalog metadata from the incoming V-FASTR data products, and a web-based data portal that facilitates browsing and inspection of the available metadata for candidate events extracted from the VLBA radio data.

  19. Mass gathering medicine: event factors predicting patient presentation rates.

    PubMed

    Locoh-Donou, Samuel; Yan, Guofen; Berry, Thomas; O'Connor, Robert; Sochor, Mark; Charlton, Nathan; Brady, William

    2016-08-01

    This study was conducted to identify the event characteristics of mass gatherings that predict patient presentation rates held in a southeastern US university community. We conducted a retrospective review of all event-based emergency medical services (EMS) records from mass gathering patient presentations over an approximate 23 month period, from October 24, 2009 to August 27, 2011. All patrons seen by EMS were included. Event characteristics included: crowd size, venue percentage filled seating, venue location (inside/outside), venue boundaries (bounded/unbounded), presence of free water (i.e., without cost), presence of alcohol, average heat index, presence of climate control (i.e., air conditioning), and event category (football, concerts, public exhibitions, non-football athletic events). We identified 79 mass gathering events, for a total of 670 patient presentations. The cumulative patron attendance was 917,307 persons. The patient presentation rate (PPR) for each event was calculated as the number of patient presentations per 10,000 patrons in attendance. Overdispersed Poisson regression was used to relate this rate to the event characteristics while controlling for crowd size. In univariate analyses, increased rates of patient presentations were strongly associated with outside venues [rate ratio (RR) = 3.002, p < 0.001], unbounded venues (RR = 2.839, p = 0.001), absence of free water (RR = 1.708, p = 0.036), absence of climate control (RR = 3.028, p < 0.001), and a higher heat index (RR = 1.211 per 10-unit heat index increase, p = 0.003). The presence of alcohol was not significantly associated with the PPR. Football events had the highest PPR, followed sequentially by public exhibitions, concerts, and non-football athletic events. In multivariate models, the strong predictors from the univariate analyses retained their predictive significance for the PPR, together with heat index and percent seating. In the setting of mass event

  20. Neutron-induced single event burnout in high voltage electronics

    SciTech Connect

    Normand, E.; Wert, J.L.; Oberg, D.L.; Majewski, P.P.; Voss, P.; Wender, S.A.

    1997-12-01

    Energetic neutrons with an atmospheric neutron spectrum, which were demonstrated to induce single event burnout in power MOSFETs, have been shown to induce burnout in high voltage (>3,000V) electronics when operated at voltages as low as 50% of rated voltage. The laboratory failure rates correlate well with field failure rates measured in Europe.

  1. HIGH ENERGY RATE EXTRUSION.

    DTIC Science & Technology

    Thin structural shapes can now be produced by high velocity extrusion equipment. Tooling, dies, die coatings, lubricants and general processing...degrees was important in reducing the initial peak stresses to a controllable level and tooling failures were reduced by using high strength (Rc 55-60...the high inertial forces present) can be lessened and eliminated in many cases by the selection of low reduction ratios (15:1 or below) and low impact speeds. (Author)

  2. Single Event Rates for Devices Sensitive to Particle Energy

    NASA Technical Reports Server (NTRS)

    Edmonds, L. D.; Scheick, L. Z.; Banker, M. W.

    2012-01-01

    Single event rates (SER) can include contributions from low-energy particles such that the linear energy transfer (LET) is not constant. Previous work found that the environmental description that is most relevant to the low-energy contribution to the rate is a "stopping rate per unit volume" even when the physical mechanisms for a single-event effect do not require an ion to stop in some device region. Stopping rate tables are presented for four heavy-ion environments that are commonly used to assess device suitability for space applications. A conservative rate estimate utilizing limited test data is derived, and the example of SEGR rate in a power MOSFET is presented.

  3. Combination of High Rate, Real-Time GNSS and Accelerometer Observations and Rapid Seismic Event Notification for Earthquake Early Warning and Volcano Monitoring with a Focus on the Pacific Rim.

    NASA Astrophysics Data System (ADS)

    Zimakov, L. G.; Passmore, P.; Raczka, J.; Alvarez, M.; Jackson, M.

    2014-12-01

    Scientific GNSS networks are moving towards a model of real-time data acquisition, epoch-by-epoch storage integrity, and on-board real-time position and displacement calculations. This new paradigm allows the integration of real-time, high-rate GNSS displacement information with acceleration and velocity data to create very high-rate displacement records. The mating of these two instruments allows the creation of a new, very high-rate (200 sps) displacement observable that has the full-scale displacement characteristics of GNSS and high-precision dynamic motions of seismic technologies. It is envisioned that these new observables can be used for earthquake early warning studies, volcano monitoring, and critical infrastructure monitoring applications. Our presentation will focus on the characteristics of GNSS, seismic, and strong motion sensors in high dynamic environments, including historic earthquakes in Southern California and the Pacific Rim, replicated on a shake table, over a range of displacements and frequencies. We will explore the optimum integration of these sensors from a filtering perspective including simple harmonic impulses over varying frequencies and amplitudes and under the dynamic conditions of various earthquake scenarios. In addition we will discuss implementation of a Rapid Seismic Event Notification System that provides quick delivery of digital data from seismic stations to the acquisition and processing center and a full data integrity model for real-time earthquake notification that provides warning prior to significant ground shaking.

  4. The annoyance of multiple noisy events. [ratings for simulated flyovers

    NASA Technical Reports Server (NTRS)

    Ahumada, A., Jr.; Nagel, D. C.

    1979-01-01

    A total of 24 subjects (17 M, 7 F) was tested in an experimental study of annoyance rating of multiple noisy events (30 sets of noise bursts). The scaling technique known as functional measurement was used to determine whether annoyance integrates additively over events and if so, to measure the power law exponent which relates the levels of the events to the additive scale values. To this end, groups of three noises were presented at three levels in a factorial arrangement to check the additivity hypothesis and to estimate the scaling function. Also, a series of sets of noises of constant level but varying in set size were considered. The functional measurement of annoyance ratings of sets of three simulated flyovers showed that the integration of annoyance can be represented as an additive process in terms of scale values that are power functions of the sound power with a power-law exponent near 0.7.

  5. Predicting Proton-Induced Single Event Upsets Rates

    NASA Astrophysics Data System (ADS)

    Reed, Robert Andrew

    Microelectronic devices are susceptible to single event effects in some space radiation environments. A traversal by a single energetic particle that leads to a change in the information stored on a single memory element is known as a single event upset. The cross section for producing an upset can vary with the angle of incidence of the proton, depending on the dimensions of the sensitive volume and the critical charge. Satellites encounter a high proton flux region when they traverse the inner radiation belts in space. The goal of this research was to develop an algorithm for predicting proton-induced memory upset rates for orbits that cross these belts that includes the angular variations in the upset cross section. This required extending an existing Monte-Carlo code that simulates proton -induced spallation reactions in silicon to be capable of handling protons incident at any angle of incidence. These codes were used to predict upset cross sections. The radiation environment was modeled as a set of monoenergetic omnidirectional proton beams where the relative flux at each energy was predicted by AP8. The shielding that surrounds a device was assumed to be a six sided shell. Protons that traverse the shell will enter the device with a new energy. A shielding code was developed that translated each omnidirectional exposure into a new spectrum of energies. Each spectrum was used as input into the Monte-Carlo code which determined the angle-average upset cross section for that incident proton energy (i.e., the proton's energy before traversing the shielding). The upset rate was predicted from the cross section predictions and the flux prediction of AP8. Applying the codes to specific devices requires knowledge of the dimensions of the sensitive volume and the critical charge, i.e., the threshold energy that must be deposited in the sensitive volume to upset the device. These parameters were determined for four devices flown as part of the Microelectronic Package

  6. Moving Beyond JUPITER: Will Inhibiting Inflammation Reduce Vascular Event Rates?

    PubMed Central

    Ridker, Paul M

    2013-01-01

    The recent JUPITER trial demonstrated that potent statin therapy reduces by 50 percent the risk of heart attack and stroke among men and women with low levels of LDL-cholesterol who are at increased vascular risk due to elevated levels of CRP, a biomarker of low-grade systemic inflammation. In JUPITER, both absolute risk and the absolute risk reduction with statin therapy in JUPITER were related to the level of CRP whereas no such relationship was observed for LDL-C. Further, on-treatment levels of CRP and LDL-C were independently associated with residual risk, and the genetic determinants of statin-induced CRP reduction differed from the genetic determinants of statin-induced LDL reduction. Despite these data, it is impossible in any statin trial to establish whether the clinical benefits of treatment are due to LDL-reduction alone, to inflammation inhibition, or to a combination of both processes To address the hypothesis that lowering inflammation will lower vascular event rates, two large-scale placebo controlled trials using targeted anti-inflammatory agents for the secondary prevention of myocardial infarction have been initiated. The first trial, the Canakinumab Anti-Inflammatory Thrombosis Outcomes Study (CANTOS) is evaluating whether interleukin-1β (IL-1β) inhibition as compared to placebo can reduce rates of recurrent myocardial infarction, stroke, and cardiovascular death among stable coronary artery disease patients who remain at high vascular risk due to persistent elevations of hsCRP (≥2 mg/L) despite contemporary secondary prevention strategies. The second trial, the Cardiovascular Inflammation Reduction Trial (CIRT) has been funded by the NHLBI and will evaluate whether low dose methotrexate (target dose 20 mg/week) as compared to placebo will reduce major vascular events among a group of post-myocardial infarction patients with either diabetes or metabolic syndrome, groups known to have high risk on the basis of a persistent pro

  7. Net reclassification index at event rate: properties and relationships.

    PubMed

    Pencina, Michael J; Steyerberg, Ewout W; D'Agostino, Ralph B

    2016-07-18

    The net reclassification improvement (NRI) is an attractively simple summary measure quantifying improvement in performance because of addition of new risk marker(s) to a prediction model. Originally proposed for settings with well-established classification thresholds, it quickly extended into applications with no thresholds in common use. Here we aim to explore properties of the NRI at event rate. We express this NRI as a difference in performance measures for the new versus old model and show that the quantity underlying this difference is related to several global as well as decision analytic measures of model performance. It maximizes the relative utility (standardized net benefit) across all classification thresholds and can be viewed as the Kolmogorov-Smirnov distance between the distributions of risk among events and non-events. It can be expressed as a special case of the continuous NRI, measuring reclassification from the 'null' model with no predictors. It is also a criterion based on the value of information and quantifies the reduction in expected regret for a given regret function, casting the NRI at event rate as a measure of incremental reduction in expected regret. More generally, we find it informative to present plots of standardized net benefit/relative utility for the new versus old model across the domain of classification thresholds. Then, these plots can be summarized with their maximum values, and the increment in model performance can be described by the NRI at event rate. We provide theoretical examples and a clinical application on the evaluation of prognostic biomarkers for atrial fibrillation. Copyright © 2016 John Wiley & Sons, Ltd.

  8. High-Energy Solar Particle Events in Cycle 24

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.; Makela, P.; Yashiro, S.; Xie, H.; Akiyama, S.; Thakur, N.

    2015-01-01

    The Sun is already in the declining phase of cycle 24, but the paucity of high-energy solar energetic particle (SEP) events continues with only two ground level enhancement (GLE) events as of March 31, 2015. In an attempt to understand this, we considered all the large SEP events of cycle 24 that occurred until the end of 2014. We compared the properties of the associated CMEs with those in cycle 23. We found that the CME speeds in the sky plane were similar, but almost all those cycle-24 CMEs were halos. A significant fraction of (16%) of the frontside SEP events were associated with eruptive prominence events. CMEs associated with filament eruption events accelerate slowly and attain peak speeds beyond the typical GLE release heights. When we considered only western hemispheric events that had good connectivity to the CME nose, there were only 8 events that could be considered as GLE candidates. One turned out to be the first GLE event of cycle 24 (2012 May 17). In two events, the CMEs were very fast (>2000 km/s) but they were launched into a tenuous medium (high Alfven speed). In the remaining five events, the speeds were well below the typical GLE CME speed (2000 km/s). Furthermore, the CMEs attained their peak speeds beyond the typical heights where GLE particles are released. We conclude that several factors contribute to the low rate of high-energy SEP events in cycle 24: (i) reduced efficiency of shock acceleration (weak heliospheric magnetic field), (ii) poor latitudinal and longitudinal connectivity), and (iii) variation in local ambient conditions (e.g., high Alfven speed).

  9. High-Energy Solar Particle Events in Cycle 24

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.; Makela, P.; Yashiro, S.; Xie, H.; Akiyama, S.; Thakur, N.

    2015-01-01

    The Sun is already in the declining phase of cycle 24, but the paucity of high-energy solar energetic particle (SEP) events continues with only two ground level enhancement (GLE) events as of March 31, 2015. In an attempt to understand this, we considered all the large SEP events of cycle 24 that occurred until the end of 2014. We compared the properties of the associated CMEs with those in cycle 23. We found that the CME speeds in the sky plane were similar, but almost all those cycle-24 CMEs were halos. A significant fraction of (16%) of the frontside SEP events were associated with eruptive prominence events. CMEs associated with filament eruption events accelerate slowly and attain peak speeds beyond the typical GLE release heights. When we considered only western hemispheric events that had good connectivity to the CME nose, there were only 8 events that could be considered as GLE candidates. One turned out to be the first GLE event of cycle 24 (2012 May 17). In two events, the CMEs were very fast (>2000 km/s) but they were launched into a tenuous medium (high Alfven speed). In the remaining five events, the speeds were well below the typical GLE CME speed (2000 km/s). Furthermore, the CMEs attained their peak speeds beyond the typical heights where GLE particles are released. We conclude that several factors contribute to the low rate of high-energy SEP events in cycle 24: (i) reduced efficiency of shock acceleration (weak heliospheric magnetic field), (ii) poor latitudinal and longitudinal connectivity), and (iii) variation in local ambient conditions (e.g., high Alfven speed).

  10. The High Latitude D Region During Electron Precipitation Events

    NASA Technical Reports Server (NTRS)

    Hargreaves, J. K.; Collis, P. N.; Korth, A.

    1984-01-01

    The fluxes of energetic electrons entering the high-latitude atmosphere during auroral radio absorption events and their effect on the electron density in the auroral D region are discussed. An attempt was made to calculate the radio absorption during precipitation events from the fluxes of energetic electrons measured at geosynchronous orbit, and then to consider the use of absorption measurements to indicate the magnetospheric particle fluxes, the production rates, and electron densities in the D region.

  11. Negative affect predicts adults' ratings of the current, but not childhood, impact of adverse childhood events.

    PubMed

    LaNoue, Marianna; Graeber, David A; Helitzer, Deborah L; Fawcett, Jan

    2013-10-01

    Adverse childhood events (ACE's) have been empirically related to a wide range of negative health and mental health outcomes. However, not all individuals who experience ACE's follow a trajectory of poor outcomes, and not all individuals perceive the impact of ACE's as necessarily negative. The purpose of this study was to investigate positive and negative affect as predictors of adults' ratings of both the childhood and adult impact of their childhood adversity. Self-report data on ACE experiences, including number, severity, and 'impact' were collected from 158 community members recruited on the basis of having adverse childhood experiences. Results indicated that, regardless of event severity and number of different types of adverse events experienced, high levels of negative affect were the strongest predictor of whether the adult impact of the adverse childhood events was rated as negative. All individuals rated the childhood impact of events the same. Implications are discussed.

  12. High Rate Digital Demodulator ASIC

    NASA Technical Reports Server (NTRS)

    Ghuman, Parminder; Sheikh, Salman; Koubek, Steve; Hoy, Scott; Gray, Andrew

    1998-01-01

    The architecture of High Rate (600 Mega-bits per second) Digital Demodulator (HRDD) ASIC capable of demodulating BPSK and QPSK modulated data is presented in this paper. The advantages of all-digital processing include increased flexibility and reliability with reduced reproduction costs. Conventional serial digital processing would require high processing rates necessitating a hardware implementation in other than CMOS technology such as Gallium Arsenide (GaAs) which has high cost and power requirements. It is more desirable to use CMOS technology with its lower power requirements and higher gate density. However, digital demodulation of high data rates in CMOS requires parallel algorithms to process the sampled data at a rate lower than the data rate. The parallel processing algorithms described here were developed jointly by NASA's Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL). The resulting all-digital receiver has the capability to demodulate BPSK, QPSK, OQPSK, and DQPSK at data rates in excess of 300 Mega-bits per second (Mbps) per channel. This paper will provide an overview of the parallel architecture and features of the HRDR ASIC. In addition, this paper will provide an over-view of the implementation of the hardware architectures used to create flexibility over conventional high rate analog or hybrid receivers. This flexibility includes a wide range of data rates, modulation schemes, and operating environments. In conclusion it will be shown how this high rate digital demodulator can be used with an off-the-shelf A/D and a flexible analog front end, both of which are numerically computer controlled, to produce a very flexible, low cost high rate digital receiver.

  13. High Rate GPS on Volcanoes

    NASA Astrophysics Data System (ADS)

    Mattia, M.

    2005-12-01

    The high rate GPS data processing can be considered as the "new deal" in geodetic monitoring of active volcanoes. Before an eruption, infact, transient episodes of ground displacements related to the dynamics of magmatic fluids can be revealed through a careful analysis of high rate GPS data. In the very first phases of an eruption the real time processing of high rate GPS data can be used by the authorities of Civil Protection to follow the opening of fractures field on the slopes of the volcanoes. During an eruption large explosions, opening of vents, migration of fractures fields, landslides and other dangerous phenomena can be followed and their potential of damage estimated by authorities. Examples from the recent eruption of Stromboli volcano and from the current activities of high rate GPS monitoring on Mt. Etna are reported, with the aim to show the great potential and the perspectives of this technique.

  14. Statistical studies of impulsive events at high latitudes

    NASA Technical Reports Server (NTRS)

    Lin, Z. M.; Bering, E. A.; Benbrook, J. R.; Liao, B.; Lanzerotti, L. J.; Maclennan, C. G.; Wolfe, A. N.; Friis-Christensen, E.

    1995-01-01

    A statistical study has been made of the high-latitude impulsive events that were observed during the 1985-1986 South Pole Balloon Campaign. The events were selected by searching for unipolar pulses greater than or equal to 10 nT above background in the vertical component of the magnetic field on the ground and/or pedestal or 'W' shaped horizontal electric field perturbations greater than or equal to 10 mV/m in amplitude and accompanied by perturbations in the vertical electric field at balloon altitude. A main event list comprising 112 events was compiled from the 468 hours of data available. Three aspects of the events were examined: the solar wind conditions prior to the event, local time of observation, and intrinsic properties of the events. The local time distribution was obtained from the 112 entry main event list and was found to be nearly uniform across the dayside, with no midday gap. The event rate found using our low-amplitude selection criteria was 0.7 event/hr, comparable to expectations based on in situ studies of the magnetopause. A total of 42 events were found for which data were available from Interplanetary Monitoring Platform (IMP) 8. Of these events, 12 occurred when the Z(sub GSM) component (B(sub Z)) of the interplanetary magnetic field (IMF) was northward and 30 occurred when B(sub Z) was southward or fluctuating. Only three of the B(sub Z) northward cases and only five of the B(sub Z) southward cases were preceded by pressure pulses greater than 0.4 nPa in amplitude. Ten of the events were studied in detail by means of a model-fitting method discussed elsewhere. This method infers values of several parameters, including the total current flowing in a coaxial or monopole system and a two-dimensional dipole system. The intrinsic properties of the events showed that only approximately 10% of the total current contributed to momentum transfer to the high-latitude ionosphere, that the direction of the motion depended more on local time of

  15. Imaging transient events at high angular resolution

    NASA Astrophysics Data System (ADS)

    Schaefer, Gail H.

    2016-08-01

    Resolving the spatial structure of transient events provides insights into their physical nature and origin. Recent observations using long baseline optical/infrared interferometry have revealed the size, shape, and angular expansion of bright novae within a few days after their outbursts. This has implications for understanding the timescale for the development of asymmetric features in novae ejecta. Additionally, combining spectroscopic measurements of the expansion velocity with the angular expansion rate provides a way to measure a geometric distance to the nova. In this paper, I provide a review of interferometric observations of novae, with a focus on recent results on the expansion and spatial structure of nova V339 Del in 2013. I also discuss other promising applications of interferometry to transient sources, such as measuring the image size and centroid displacements to measure planetary masses in gravitational microlensing events. Given the timescales of transient events, it is critical for interferometric arrays to respond rapidly to targets of opportunity in order to optimize the instrumental sensitivity and baselines required to resolve the source while its brightness and size change over time.

  16. Dose Escalation Improves Cancer-Related Events at 10 Years for Intermediate- and High-Risk Prostate Cancer Patients Treated With Hypofractionated High-Dose-Rate Boost and External Beam Radiotherapy

    SciTech Connect

    Martinez, Alvaro A.; Gonzalez, Jose; Ye Hong; Ghilezan, Mihai; Shetty, Sugandh; Kernen, Kenneth; Gustafson, Gary; Krauss, Daniel; Vicini, Frank; Kestin, Larry

    2011-02-01

    Purpose: To evaluate the 10-year outcomes of intermediate- and high-risk prostate cancer patients treated with a prospective dose escalation hypofractionated trial of pelvic external beam radiation therapy (P-EBRT) with a high-dose-rate (HDR) brachytherapy boost. Methods and Materials: From 1992 to 2007, 472 patients were treated with a HDR boost at William Beaumont Hospital. They had at least one of the following: a prostate-specific antigen (PSA) level of >10 ng/ml, a Gleason score of {>=}7, or clinical stage {>=}T2b. Patients received 46-Gy P-EBRT and an HDR boost. The HDR dose fractionation was divided into two dose levels. The prostate biologically equivalent dose (BED) low-dose-level group received <268 Gy, and the high-dose group received >268 Gy . Phoenix biochemical failure (BF) definition was used. Results: Median follow-up was 8.2 years (range, 0.4-17 years). The 10-year biochemical failure rate of 43.1% vs. 18.9%, (p < 0.001), the clinical failure rate of 23.4% vs. 7.7%, (p < 0.001), and the distant metastasis of 12.4% vs. 5.7%, (p = 0.028) were all significantly better for the high-dose level group. On Cox multivariate analysis, higher BED levels (p = 0.017; hazard ratio [HR]= 0.586), pretreatment PSA assays (p < 0.001, HR = 1.022), and Gleason scores (p = 0.004) were significant variables for reduced biochemical failure. Higher dose levels (p, 0.002; HR, 0.397) and Gleason scores (p < 0.001) were significant for clinical failure. Grade 3 genitourinary complications were 2% and 3%, respectively, and grade 3 gastrointestinal complication was <0.5%. Conclusions: This prospective trial using P-EBRT with HDR boost and hypofractionated dose escalation demonstrates a strong dose-response relationship for intermediate- and high-risk prostate cancer patients. The improvement at 10 years for locoregional control with higher radiation doses (BED, > 268Gy) has significantly decreased biochemical and clinical failures as well as distant metastasis.

  17. Comparison of single event upset rates for microelectronic memory devices during interplanetary solar particle events

    NASA Astrophysics Data System (ADS)

    McKerracher, P. L.; Kinnison, J. D.; Maurer, R. H.

    Variability in the methods and models used for single event upset calculations in microelectronic memory devices can lead to a range of possible upset rates. Using heavy ion and proton data for selected DRAM and SRAM memories, we have calculated an array of upset rates in order to compare the Adams worst case interplanetary solar flare model to a model proposed by scientists at the Jet Propulsion Laboratory. In addition, methods of upset rate calculation are compared: the Cosmic Ray Effects on Microelectronics CREME code and a Monte Carlo algorithm developed at the Applied Physics Laboratory. The results show that use of a more realistic, although still conservative, model of the space environment can have significant cost saving benefits.

  18. Comparison of single event upset rates for microelectronic memory devices during interplanetary solar particle events

    NASA Technical Reports Server (NTRS)

    Mckerracher, P. L.; Kinnison, J. D.; Maurer, R. H.

    1993-01-01

    Variability in the methods and models used for single event upset calculations in microelectronic memory devices can lead to a range of possible upset rates. Using heavy ion and proton data for selected DRAM and SRAM memories, we have calculated an array of upset rates in order to compare the Adams worst case interplanetary solar flare model to a model proposed by scientists at the Jet Propulsion Laboratory. In addition, methods of upset rate calculation are compared: the Cosmic Ray Effects on Microelectronics CREME code and a Monte Carlo algorithm developed at the Applied Physics Laboratory. The results show that use of a more realistic, although still conservative, model of the space environment can have significant cost saving benefits.

  19. A high rate proportional chamber

    SciTech Connect

    Henderson, R.; Fraszer, W.; Openshaw, R.; Sheffer, G.; Salomon, M.; Dew, S.; Marans, J.; Wilson, P.

    1987-02-01

    Gas mixtures with high specific ionization allow the use of small interelectrode distances while still maintaining full efficiency. With the short electron drift distances the timing resolution is also improved. The authors have built and operated two 25 cm/sup 2/ chambers with small interelectrode distances. Also single wire detector cells have been built to test gas mixture lifetimes. Various admixtures of CF/sub 4/, DME, Isobutane, Ethane and Argon have been tested. Possible applications of such chambers are as beam profile monitors, position tagging of rare events and front end chambers in spectrometers.

  20. Predicting binary merger event rates for advanced LIGO/Virgo

    NASA Astrophysics Data System (ADS)

    Holz, Daniel; Belczynski, Chris; O'Shaughnessy, Richard; Bulik, Tomek; LIGO Collaboration

    2016-03-01

    We discuss estimates of the rates of mergers of binary systems composed of neutron stars and/or stellar mass black holes. We use the StarTrack population synthesis code, and make predictions for the detection rate of compact binary coalescences with the advanced LIGO/Virgo gravitational wave detectors. Because these instruments are sensitive to massive (M > 20M⊙) stellar-mass binary black holes mergers out to high redshift (z > 1), we discuss the cosmological effects which must be taken into account when calculating LIGO detection rates, including a generalization of the calculation of the ``peanut factor'' and the sensitive time-volume.

  1. High Data Rate Instrument Study

    NASA Technical Reports Server (NTRS)

    Schober, Wayne; Lansing, Faiza; Wilson, Keith; Webb, Evan

    1999-01-01

    The High Data Rate Instrument Study was a joint effort between the Jet Propulsion Laboratory (JPL) and the Goddard Space Flight Center (GSFC). The objectives were to assess the characteristics of future high data rate Earth observing science instruments and then to assess the feasibility of developing data processing systems and communications systems required to meet those data rates. Instruments and technology were assessed for technology readiness dates of 2000, 2003, and 2006. The highest data rate instruments are hyperspectral and synthetic aperture radar instruments which are capable of generating 3.2 Gigabits per second (Gbps) and 1.3 Gbps, respectively, with a technology readiness date of 2003. These instruments would require storage of 16.2 Terebits (Tb) of information (RF communications case of two orbits of data) or 40.5 Tb of information (optical communications case of five orbits of data) with a technology readiness date of 2003. Onboard storage capability in 2003 is estimated at 4 Tb; therefore, all the data created cannot be stored without processing or compression. Of the 4 Tb of stored data, RF communications can only send about one third of the data to the ground, while optical communications is estimated at 6.4 Tb across all three technology readiness dates of 2000, 2003, and 2006 which were used in the study. The study includes analysis of the onboard processing and communications technologies at these three dates and potential systems to meet the high data rate requirements. In the 2003 case, 7.8% of the data can be stored and downlinked by RF communications while 10% of the data can be stored and downlinked with optical communications. The study conclusion is that only 1 to 10% of the data generated by high data rate instruments will be sent to the ground from now through 2006 unless revolutionary changes in spacecraft design and operations such as intelligent data extraction are developed.

  2. Conditional Probabilities for Large Events Estimated by Small Earthquake Rate

    NASA Astrophysics Data System (ADS)

    Wu, Yi-Hsuan; Chen, Chien-Chih; Li, Hsien-Chi

    2016-01-01

    We examined forecasting quiescence and activation models to obtain the conditional probability that a large earthquake will occur in a specific time period on different scales in Taiwan. The basic idea of the quiescence and activation models is to use earthquakes that have magnitudes larger than the completeness magnitude to compute the expected properties of large earthquakes. We calculated the probability time series for the whole Taiwan region and for three subareas of Taiwan—the western, eastern, and northeastern Taiwan regions—using 40 years of data from the Central Weather Bureau catalog. In the probability time series for the eastern and northeastern Taiwan regions, a high probability value is usually yielded in cluster events such as events with foreshocks and events that all occur in a short time period. In addition to the time series, we produced probability maps by calculating the conditional probability for every grid point at the time just before a large earthquake. The probability maps show that high probability values are yielded around the epicenter before a large earthquake. The receiver operating characteristic (ROC) curves of the probability maps demonstrate that the probability maps are not random forecasts, but also suggest that lowering the magnitude of a forecasted large earthquake may not improve the forecast method itself. From both the probability time series and probability maps, it can be observed that the probability obtained from the quiescence model increases before a large earthquake and the probability obtained from the activation model increases as the large earthquakes occur. The results lead us to conclude that the quiescence model has better forecast potential than the activation model.

  3. Role of high shear rate in thrombosis.

    PubMed

    Casa, Lauren D C; Deaton, David H; Ku, David N

    2015-04-01

    Acute arterial occlusions occur in high shear rate hemodynamic conditions. Arterial thrombi are platelet-rich when examined histologically compared with red blood cells in venous thrombi. Prior studies of platelet biology were not capable of accounting for the rapid kinetics and bond strengths necessary to produce occlusive thrombus under these conditions where the stasis condition of the Virchow triad is so noticeably absent. Recent experiments elucidate the unique pathway and kinetics of platelet aggregation that produce arterial occlusion. Large thrombi form from local release and conformational changes in von Willebrand factor under very high shear rates. The effect of high shear hemodynamics on thrombus growth has profound implications for the understanding of all acute thrombotic cardiovascular events as well as for vascular reconstructive techniques and vascular device design, testing, and clinical performance. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  4. Source rupture process of the 5 September 2012 Costa Rica Mw=7.6 thrust event from joint inversion of high-rate GPS, strong motion, and teleseismic P wave data

    NASA Astrophysics Data System (ADS)

    Lay, T.; Yue, H.; Rivera, L. A.; Schwartz, S. Y.; Protti, M.

    2013-05-01

    On 5 September 2012, a large thrust event (Mw=7.6) ruptured a densely instrumented seismic gap on the shallow plate boundary beneath the Nicoya Peninsula, Costa Rica. Networks of strong motion accelerometers, broadband and short-period sensors, and high-rate (5-sps) GPS stations recorded ground motions directly above the rupture zone, providing a unique opportunity to study the detailed source process of a large shallow megathrust rupture using nearby land observations. An inland and relatively deep hypocenter (10.086°N, 85.305°W, 40 km) was estimated by the USGS, and teleseismic W-phase inversions also indicate a relatively large (30-40 km) centroid depth. Hypocenter relocation performed using the local seismic network data indicates that the event initiated with small emergent seismic waves from a hypocenter ~10 km offshore (9.80°N, 85.53°W) 15 km deep on the megathrust. The local origin time (14:42:05) is 3 s earlier than the USGS origin time, compatible with the shallower source depth. A joint finite-fault inversion of 0.2 Hz lowpass-filtered hr-GPS recordings, <0.4 Hz ground velocity recordings from regional strong-motion sensors, and teleseismic P waves reveals that the primary slip zone is located beneath the Nicoya coastline up-dip from the USGS location. Complete ground motions are computed for the hr-GPS stations using a 1D regional velocity model and a wavenumber integration program from Robert Herrmann. The large-slip region extends ~50 km along strike and ~30 km along dip, with a centroid depth of ~23 km. The maximum slip is ~4 meters and Mw=7.6, consistent with teleseismic estimates. The inversion indicates that the rupture propagated down-dip from the offshore hypocenter with a rupture velocity of ~2.5 km/s. The inversion has limited resolution of any offshore slip, but slip occurred in a region about 30 km offshore along the northern half of the rupture zone. We consider the relationship between coseismic slip location, aftershocks and adjacent

  5. Rates of minor adverse events and health resource utilization postcolonoscopy.

    PubMed

    Marquez Azalgara, Vladimir; Sewitch, Maida J; Joseph, Lawrence; Barkun, Alan N

    2014-12-01

    Little is known about minor adverse events (MAEs) following outpatient colonoscopies and associated health care resource utilization. To estimate the rates of incident MAE at two, 14 and 30 days postcolonoscopy, and associated health care resource utilization. A secondary aim was to identify factors associated with cumulative 30-day MAE incidence. A longitudinal cohort study was conducted among individuals undergoing an outpatient colonoscopy at the Montreal General Hospital (Montreal, Quebec). Before colonoscopy, consecutive individuals were enrolled and interviewed to obtain data regarding age, sex, comorbidities, use of antiplatelets/anticoagulants and previous symptoms. Endoscopy reports were reviewed for intracolonoscopy procedures (biopsy, polypectomy). Telephone or Internet follow-up was used to obtain data regarding MAEs (abdominal pain, bloating, diarrhea, constipation, nausea, vomiting, blood in the stools, rectal or anal pain, headaches, other) and health resource use (visits to emergency department, primary care doctor, gastroenterologist; consults with nurse, pharmacist or telephone hotline). Rates of incident MAEs and health resources utilization were estimated using Bayesian hierarchical modelling to account for patient clustering within physician practices. Of the 705 individuals approached, 420 (59.6%) were enrolled. Incident MAE rates at the two-, 14- and 30-day follow-ups were 17.3% (95% credible interval [CrI] 8.1% to 30%), 10.5% (95% CrI 2.9% to 23.7%) and 3.2% (95% CrI 0.01% to 19.8%), respectively. The 30-day rate of health resources utilization was 1.7%, with 0.95% of participants seeking the services of a physician. No predictors of the cumulative 30-day incidence of MAEs were identified. The incidence of MAEs was highest in the 48 h following colonoscopy and uncommon after two weeks, supporting the Canadian Association of Gastroenterology's recommendation for assessment of late complications at 14 days. Predictors of new onset of MAEs were

  6. Rates of minor adverse events and health resource utilization postcolonoscopy

    PubMed Central

    Azalgara, Vladimir Marquez; Sewitch, Maida J; Joseph, Lawrence; Barkun, Alan N

    2014-01-01

    BACKGROUND: Little is known about minor adverse events (MAEs) following outpatient colonoscopies and associated health care resource utilization. OBJECTIVE: To estimate the rates of incident MAE at two, 14 and 30 days postcolonoscopy, and associated health care resource utilization. A secondary aim was to identify factors associated with cumulative 30-day MAE incidence. METHODS: A longitudinal cohort study was conducted among individuals undergoing an outpatient colonoscopy at the Montreal General Hospital (Montreal, Quebec). Before colonoscopy, consecutive individuals were enrolled and interviewed to obtain data regarding age, sex, comorbidities, use of antiplatelets/anticoagulants and previous symptoms. Endoscopy reports were reviewed for intracolonoscopy procedures (biopsy, polypectomy). Telephone or Internet follow-up was used to obtain data regarding MAEs (abdominal pain, bloating, diarrhea, constipation, nausea, vomiting, blood in the stools, rectal or anal pain, headaches, other) and health resource use (visits to emergency department, primary care doctor, gastroenterologist; consults with nurse, pharmacist or telephone hotline). Rates of incident MAEs and health resources utilization were estimated using Bayesian hierarchical modelling to account for patient clustering within physician practices. RESULTS: Of the 705 individuals approached, 420 (59.6%) were enrolled. Incident MAE rates at the two-, 14- and 30-day follow-ups were 17.3% (95% credible interval [CrI] 8.1% to 30%), 10.5% (95% CrI 2.9% to 23.7%) and 3.2% (95% CrI 0.01% to 19.8%), respectively. The 30-day rate of health resources utilization was 1.7%, with 0.95% of participants seeking the services of a physician. No predictors of the cumulative 30-day incidence of MAEs were identified. DISCUSSION: The incidence of MAEs was highest in the 48 h following colonoscopy and uncommon after two weeks, supporting the Canadian Association of Gastroenterology’s recommendation for assessment of late

  7. High data rate optical crosslinks

    NASA Astrophysics Data System (ADS)

    Boroson, Don M.; Bondurant, Roy S.

    1992-03-01

    Optical technologies, due to their extremely short wavelengths, can be designed to be much more compact than RF when addressing high data rate crosslinks and multiple apertures approaching the multi-Gbps operational range. Currently available optical technologies can furnish hundreds-of- Mbps in a package of less than 100 lbs and several cubic feet. Attention is presently given to communications and spatial acquisition/tracking system analysis, the character of such space-qualified optics hardware as the requisite laser transmitter, and advanced hardware prototypes.

  8. Evaluation of vaccine seroresponse rates and adverse event rates through Bayesian and frequentist methods.

    PubMed

    Liu, Jin; Chen, Feng; Zhu, Feng-Cai; Bai, Jian-Ling; Li, Jing-Xin; Yu, Hao; Liu, Pei; Zeng, Ping

    2015-01-01

    In the evaluation of vaccine seroresponse rates and adverse reaction rates, extreme test results often occur, with substantial adverse event rates of 0% and/or seroresponse rates of 100%, which has produced several data challenges. Few studies have used both the Bayesian and frequentist methods on the same sets of data that contain extreme test cases to evaluate vaccine safety and immunogenicity. In this study, Bayesian methods were introduced, and the comparison with frequentist methods was made based on practical cases from randomized controlled vaccine trials and a simulation experiment to examine the rationality of the Bayesian methods. The results demonstrated that the Bayesian non-informative method obtained lower limits (for extreme cases of 100%) and upper limits (for extreme cases of zero), which were similar to the limits that were identified with the frequentist method. The frequentist rate estimates and corresponding confidence intervals (CIs) for extreme cases of 0 or 100% always equaled and included 0 or 100%, respectively, whereas the Bayesian estimations varied depending on the sample size, with none equaling zero or 100%. The Bayesian method obtained more reasonable interval estimates of the rates with extreme data compared with the frequentist method, whereas the frequentist method objectively expressed the outcomes of clinical vaccine trials. The two types of statistical results are complementary, and it is proposed that the Bayesian and frequentist methods should be combined to more comprehensively evaluate clinical vaccine trials.

  9. High event-free survival rate with minimum-dose-anthracycline treatment in childhood acute promyelocytic leukaemia: a nationwide prospective study by the Japanese Paediatric Leukaemia/Lymphoma Study Group.

    PubMed

    Takahashi, Hiroyuki; Watanabe, Tomoyuki; Kinoshita, Akitoshi; Yuza, Yuki; Moritake, Hiroshi; Terui, Kiminori; Iwamoto, Shotaro; Nakayama, Hideki; Shimada, Akira; Kudo, Kazuko; Taki, Tomohiko; Yabe, Miharu; Matsushita, Hiromichi; Yamashita, Yuka; Koike, Kazutoshi; Ogawa, Atsushi; Kosaka, Yoshiyuki; Tomizawa, Daisuke; Taga, Takashi; Saito, Akiko M; Horibe, Keizo; Nakahata, Tatsutoshi; Miyachi, Hayato; Tawa, Akio; Adachi, Souichi

    2016-08-01

    We evaluated the efficacy of treatment using reduced cumulative doses of anthracyclines in children with acute promyelocytic leukaemia (APL) in the Japanese Paediatric Leukaemia/Lymphoma Study Group AML-P05 study. All patients received two and three subsequent courses of induction and consolidation chemotherapy respectively, consisting of all-trans retinoic acid (ATRA), cytarabine and anthracyclines, followed by maintenance therapy with ATRA. Notably, a single administration of anthracyclines was introduced in the second induction and all consolidation therapies to minimize total doses of anthracycline. The 3-year event-free (EFS) and overall survival rates for 43 eligible children were 83·6% [95% confidence interval (CI): 68·6-91·8%] and 90·7% (95% CI: 77·1-96·4%), respectively. Although two patients died of intracranial haemorrhage or infection during induction phases, no cardiac adverse events or treatment-related deaths were observed during subsequent phases. Patients not displaying M1 marrow after the first induction therapy, or those under 5 years of age at diagnosis, showed inferior outcomes (3-year EFS rate; 33·3% (95% CI: 19·3-67·6%) and 54·6% (95% CI: 22·9-78·0%), respectively). In conclusion, a single administration of anthracycline during each consolidation phase was sufficient for treating childhood APL. In younger children, however, conventional ATRA and chemotherapy may be insufficient so that alternative therapies should be considered. © 2016 John Wiley & Sons Ltd.

  10. High Resolution, High Frame Rate Video Technology

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Papers and working group summaries presented at the High Resolution, High Frame Rate Video (HHV) Workshop are compiled. HHV system is intended for future use on the Space Shuttle and Space Station Freedom. The Workshop was held for the dual purpose of: (1) allowing potential scientific users to assess the utility of the proposed system for monitoring microgravity science experiments; and (2) letting technical experts from industry recommend improvements to the proposed near-term HHV system. The following topics are covered: (1) State of the art in the video system performance; (2) Development plan for the HHV system; (3) Advanced technology for image gathering, coding, and processing; (4) Data compression applied to HHV; (5) Data transmission networks; and (6) Results of the users' requirements survey conducted by NASA.

  11. Hartmann's reversal is associated with high postoperative adverse events.

    PubMed

    Aydin, H Nail; Remzi, Feza H; Tekkis, Paris P; Fazio, Victor W

    2005-11-01

    The aim of this study was to ascertain the preva lence and pattern of surgical and medical adverse events in patients undergoing Hartmann's reversal for diverticular dis ease. A comparison of postoperative outcomes is made be tween Hartmann's reversal and primary resection and anas tomosis. Data were collected from patients who underwent successful Hartmann's reversal (Group 1 n=121) and primary resection and anastomosis (Group 2 n=731) for diverticular disease in a single center from January 1981 to May 2003. Multivariate logistic regression was used to compare early postoperative mortality, medical and surgical complications and readmission rates between the two groups. Hartmann's reversal was associ ated with a higher prevalence of surgical or medical com plications compared with primary resection and anastomo sis (43.8 percent and 9.1 percent for Hartmann's reversal vs. 26.0 percent and 4.8 percent for primary resection and anastomosis). There was no difference in the readmissior rates (7.2 percent vs. 7.6 percent, respectively, P = 0.88) or early postoperative mortality (1.7 percent vs. 0.7 percent, P = 0.25) between Hartmann's reversal and primary resection and anastomosis. The need for reoperation, prolonged ileus respiratory tract infections, and renal failure were more common adverse events in the Hartmann's reversal group (P < 0.01). Having controlled for the number of comorbid conditions, extent of diverticular disease, severity of peri toneal contamination (Mannheim Peritonitis Index), and op erative urgency, patients who underwent Hartmann's rever sal were 2.1 times more likely to have adverse surgical events during their postoperative period (95 percent confidence interval for odds ratio = 1.3-3.3). Hartmann's reversal is a complex surgical procedure that is associated with a high prevalence of postoperative adverse events in comparison with primary resection and anastomosis. To minimize the prevalence of such adverse events, patients who undergo

  12. Fractional field equations for highly improbable events

    NASA Astrophysics Data System (ADS)

    Kleinert, H.

    2013-06-01

    Free and weakly interacting particles perform approximately Gaussian random walks with collisions. They follow a second-quantized nonlinear Schrödinger equation, or relativistic versions of it. By contrast, the fields of strongly interacting particles extremize more involved effective actions obeying fractional wave equations with anomalous dimensions. Their particle orbits perform universal Lévy walks with heavy tails, in which rare events are much more frequent than in Gaussian random walks. Such rare events are observed in exceptionally strong windgusts, monster or rogue waves, earthquakes, and financial crashes. While earthquakes may destroy entire cities, the latter have the potential of devastating entire economies.

  13. LIMITS ON THE EVENT RATES OF FAST RADIO TRANSIENTS FROM THE V-FASTR EXPERIMENT

    SciTech Connect

    Wayth, Randall B.; Tingay, Steven J.; Deller, Adam T.; Brisken, Walter F.; Thompson, David R.; Wagstaff, Kiri L.; Majid, Walid A.

    2012-07-10

    We present the first results from the V-FASTR experiment, a commensal search for fast transient radio bursts using the Very Long Baseline Array (VLBA). V-FASTR is unique in that the widely spaced VLBA antennas provide a discriminant against non-astronomical signals and a mechanism for the localization and identification of events that is not possible with single dishes or short baseline interferometers. Thus, far V-FASTR has accumulated over 1300 hr of observation time with the VLBA, between 90 cm and 3 mm wavelength (327 MHz-86 GHz), providing the first limits on fast transient event rates at high radio frequencies (>1.4 GHz). V-FASTR has blindly detected bright individual pulses from seven known pulsars but has not detected any single-pulse events that would indicate high-redshift impulsive bursts of radio emission. At 1.4 GHz, V-FASTR puts limits on fast transient event rates comparable with the PALFA survey at the Arecibo telescope, but generally at lower sensitivities, and comparable to the 'fly's eye' survey at the Allen Telescope Array, but with less sky coverage. We also illustrate the likely performance of the Phase 1 SKA dish array for an incoherent fast transient search fashioned on V-FASTR.

  14. Properties of high-transverse-energy hadronic events

    SciTech Connect

    Brown, B.; Devenski, P.; Gronemeyer, S.

    1982-03-01

    Cross sections and event structure for events produced in pp and pA collisions with high transverse momentum are presented. The events were studied using the large acceptance Fermilab Multiparticle Spectrometer. The pp cross sections are substantially larger than predictions from the 4-jet QCD model. Production at high transverse momentum from nuclear targets increases more rapidly than the atomic mass number. The majority of the pp events are non-planar. After applying cuts to the data there is a tendency for high transverse momentum events to be more planar than ones with lower transverse momentum.

  15. 2K×2K resolution element photon counting MCP sensor with >200 kHz event rate capability

    NASA Astrophysics Data System (ADS)

    Vallerga, J. V.; Siegmund, O. H. W.

    2000-03-01

    Siegmund Scientific undertook a NASA Small Business Innovative Research (SBIR) contract to develop a versatile, high-performance photon (or particle) counting detector combining recent technical advances in all aspects of Microchannel Plate (MCP) detector development in a low cost, commercially viable package that can support a variety of applications. The detector concept consists of a set of MCPs whose output electron pulses are read out with a crossed delay line (XDL) anode and associated high-speed event encoding electronics. The delay line anode allows high-resolution photon event centroiding at very high event rates and can be scaled to large formats (>40 mm) while maintaining good linearity and high temporal stability. The optimal sensitivity wavelength range is determined by the choice of opaque photocathodes. Specific achievements included: spatial resolution of <25 μm FWHM; formats from 25 to 40 mm with digitized pixel sizes of ∼3 μm; total detector rates of >200 000 events s-1; local rates of >100 events s-1 per resolution element; event timing of <1 ns; and low background counting rates (<1 event cm-2 s-1).

  16. Gait Event Detection during Stair Walking Using a Rate Gyroscope

    PubMed Central

    Formento, Paola Catalfamo; Acevedo, Ruben; Ghoussayni, Salim; Ewins, David

    2014-01-01

    Gyroscopes have been proposed as sensors for ambulatory gait analysis and functional electrical stimulation systems. These applications often require detection of the initial contact (IC) of the foot with the floor and/or final contact or foot off (FO) from the floor during outdoor walking. Previous investigations have reported the use of a single gyroscope placed on the shank for detection of IC and FO on level ground and incline walking. This paper describes the evaluation of a gyroscope placed on the shank for determination of IC and FO in subjects ascending and descending a set of stairs. Performance was compared with a reference pressure measurement system. The absolute mean difference between the gyroscope and the reference was less than 45 ms for IC and better than 135 ms for FO for both activities. Detection success was over 93%. These results provide preliminary evidence supporting the use of a gyroscope for gait event detection when walking up and down stairs. PMID:24651724

  17. Gait event detection during stair walking using a rate gyroscope.

    PubMed

    Formento, Paola Catalfamo; Acevedo, Ruben; Ghoussayni, Salim; Ewins, David

    2014-03-19

    Gyroscopes have been proposed as sensors for ambulatory gait analysis and functional electrical stimulation systems. These applications often require detection of the initial contact (IC) of the foot with the floor and/or final contact or foot off (FO) from the floor during outdoor walking. Previous investigations have reported the use of a single gyroscope placed on the shank for detection of IC and FO on level ground and incline walking. This paper describes the evaluation of a gyroscope placed on the shank for determination of IC and FO in subjects ascending and descending a set of stairs. Performance was compared with a reference pressure measurement system. The absolute mean difference between the gyroscope and the reference was less than 45 ms for IC and better than 135 ms for FO for both activities. Detection success was over 93%. These results provide preliminary evidence supporting the use of a gyroscope for gait event detection when walking up and down stairs.

  18. Correlation of Lightning Flash Rates with a Microburst Event

    NASA Technical Reports Server (NTRS)

    Altino, Karen M.; Knupp, Kevin R.; Goodman, Steven J.

    2004-01-01

    In 1986 the MIST (Microburst and Severe - Thunderstorm) field study took place over northern Alabama. It was noted that the time of day when a peak in microburst activity was observed usually took place around 2000 UTC. It was further confirmed through the examination of the various PAM (Portable Automated Mesonet) stations that this was also the time of day where temperatures would reach their peak. On the afternoon of 18 August 2002, as the temperature approached a daily high temperature of 32 C, the first radar indication of the HSV microburst-producing storm initiated at 2020 UTC.

  19. High counting rate resistive-plate chamber

    NASA Astrophysics Data System (ADS)

    Peskov, V.; Anderson, D. F.; Kwan, S.

    1993-05-01

    Parallel-plate avalanche chambers (PPAC) are widely used in physics experiments because they are fast (less than 1 ns) and have very simple construction: just two parallel metallic plates or mesh electrodes. Depending on the applied voltage they may work either in spark mode or avalanche mode. The advantage of the spark mode of operation is a large signal amplitude from the chamber, the disadvantage is that there is a large dead time (msec) for the entire chamber after an event. The main advantage of the avalanche mode is high rate capability 10(exp 5) counts/mm(sup 2). A resistive-plate chamber (RPC) is similar to the PPAC in construction except that one or both of the electrodes are made from high resistivity (greater than 10(exp 10) Omega(cm) materials. In practice RPC's are usually used in the spark mode. Resistive electrodes are charged by sparks, locally reducing the actual electric field in the gap. The size of the charged surface is about 10 mm(sup 2), leaving the rest of the detector unaffected. Therefore, the rate capability of such detectors in the spark mode is considerably higher than conventional spark counters. Among the different glasses tested the best results were obtained with electron type conductive glasses, which obey Ohm's law. Most of the work with such glasses was done with high pressure parallel-plate chambers (10 atm) for time-of-flight measurements. Resistive glasses have been expensive and produced only in small quantities. Now resistive glasses are commercially available, although they are still expensive in small scale production. From the positive experience of different groups working with the resistive glasses, it was decided to review the old idea to use this glass for the RPC. This work has investigated the possibility of using the RPC at 1 atm and in the avalanche mode. This has several advantages: simplicity of construction, high rate capability, low voltage operation, and the ability to work with non-flammable gases.

  20. Higher event rate in patients with known CAD despite a normal myocardial perfusion scan

    PubMed Central

    Fatima, Nosheen; Zaman, Unaiza; Zaman, Areeba; Balcoh, Dad J.; Rasheed, S Zahed

    2014-01-01

    Objective The negative predictive value of a normal single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is very high. However, prognostic implication of a normal SPECT MPI in patients with known coronary artery disease (CAD) is not clear. Objective of this study was to evaluate the cardiac event rate in patients with known CAD who had a normal stress SPECT MPI. Methods This prospective study accrued 428 consecutive patients with a history of CAD [revascularization or previous myocardial infarction (MI)] who had a normal stress (dynamic exercise or dipyridamole intervention) and rest Tc-99m-MIBI SPECT MPI. These patients were followed for 2-5 years (median: 3.1 years) for all-cause and cardiac mortality and non-fatal MI. Univariate and multivariate analyses were performed to identify predictors of outcome. Results During a follow-up period, all-cause mortality was found in 60 patients (14%) and 41 (10%) died of cardiac reasons. Non-fatal MI was found in 77 (18%) patients. Annualized cardiac mortality and non-fatal MI rates were 2% and 3.6% respectively. Smoking, congestive heart failure (CHF) and failure to achieve 85% age predicted heart rate were found to be predictors for all-cause and cardiac mortality. Diabetes, dyslipidemia, smoking and limited functional capacity (<7 METS) were found to be predictors for non-fatal MI. Conclusions Patients with known CAD had higher cardiac event rates despite a normal stress SPECT MPI. Diabetes, dyslipidemia, smoking and limited functional capacity were the predictors for fatal and non-fatal cardiac events. A cost effective but comprehensive surveillance strategy is warranted. PMID:25009792

  1. Solar system events at high spatial resolution

    SciTech Connect

    Baines, K H; Gavel, D T; Getz, A M; Gibbartd, S G; MacIntosh, B; Max, C E; McKay, C P; Young, E F; de Pater, I

    1999-02-19

    Until relatively recent advances in technology, astronomical observations from the ground were limited in image resolution by the blurring effects of earth's atmosphere. The blur extent, ranging typically from 0.5 to 2 seconds of arc at the best astronomical sights, precluded ground-based observations of the details of the solar system's moons, asteroids, and outermost planets. With the maturing of a high resolution image processing technique called speckle imaging the resolution limitation of the atmosphere can now be largely overcome. Over the past three years they have used speckle imaging to observe Titan, a moon of Saturn with an atmospheric density comparable to Earth's, Io, the volcanically active innermost moon of Jupiter, and Neptune, a gas giant outer planet which has continually changing planet-encircling storms. These observations were made at the world's largest telescope, the Keck telescope in Hawaii and represent the highest resolution infrared images of these objects ever taken.

  2. Trends in rates of acetaminophen-related adverse events in the United States.

    PubMed

    Major, Jacqueline M; Zhou, Esther H; Wong, Hui-Lee; Trinidad, James P; Pham, Tracy M; Mehta, Hina; Ding, Yulan; Staffa, Judy A; Iyasu, Solomon; Wang, Cunlin; Willy, Mary E

    2016-05-01

    The goal of this study is to summarize trends in rates of adverse events attributable to acetaminophen use, including hepatotoxicity and mortality. A comprehensive analysis of data from three national surveillance systems estimated rates of acetaminophen-related events identified in different settings, including calls to poison centers (2008-2012), emergency department visits (2004-2012), and inpatient hospitalizations (1998-2011). Rates of acetaminophen-related events were calculated per setting, census population, and distributed drug units. Rates of poison center calls with acetaminophen-related exposures decreased from 49.5/1000 calls in 2009 to 43.5/1000 calls in 2012. Rates of emergency department visits for unintentional acetaminophen-related adverse events decreased from 58.0/1000 emergency department visits for adverse drug events in 2009 to 50.2/1000 emergency department visits in 2012. Rates of hospital inpatient discharges with acetaminophen-related poisoning decreased from 119.8/100 000 hospitalizations in 2009 to 108.6/100 000 hospitalizations in 2011. After 2009, population rates of acetaminophen-related events per 1 million census population decreased for poison center calls and hospitalizations, while emergency department visit rates remained stable. However, when accounting for drug sales, the rate of acetaminophen-related events (per 1 million distributed drug units) increased after 2009. Prior to 2009, the rates of acetaminophen-related hospitalizations had been slowly increasing (p-trend = 0.001). Acetaminophen-related adverse events continue to be a public health burden. Future studies with additional time points are necessary to confirm trends and determine whether recent risk mitigation efforts had a beneficial impact on acetaminophen-related adverse events. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. Published 2015. This article is a U.S. Government work and is in the public

  3. Initiating Event Rates at U.S. Nuclear Power Plants. 1988 - 2013

    SciTech Connect

    Schroeder, John A.; Bower, Gordon R.

    2014-02-01

    Analyzing initiating event rates is important because it indicates performance among plants and also provides inputs to several U.S. Nuclear Regulatory Commission (NRC) risk-informed regulatory activities. This report presents an analysis of initiating event frequencies at U.S. commercial nuclear power plants since each plant’s low-power license date. The evaluation is based on the operating experience from fiscal year 1988 through 2013 as reported in licensee event reports. Engineers with nuclear power plant experience staff reviewed each event report since the last update to this report for the presence of valid scrams or reactor trips at power. To be included in the study, an event had to meet all of the following criteria: includes an unplanned reactor trip (not a scheduled reactor trip on the daily operations schedule), sequence of events starts when reactor is critical and at or above the point of adding heat, occurs at a U.S. commercial nuclear power plant (excluding Fort St. Vrain and LaCrosse), and is reported by a licensee event report. This report displays occurrence rates (baseline frequencies) for the categories of initiating events that contribute to the NRC’s Industry Trends Program. Sixteen initiating event groupings are trended and displayed. Initiators are plotted separately for initiating events with different occurrence rates for boiling water reactors and pressurized water reactors. p-values are given for the possible presence of a trend over the most recent 10 years.

  4. Event Rates in Randomized Clinical Trials Evaluating Cardiovascular Interventions and Devices.

    PubMed

    Mahmoud, Karim D; Lennon, Ryan J; Holmes, David R

    2015-08-01

    Randomized clinical trials (RCTs) are considered the gold standard for evidence-based medicine. However, an accurate estimation of the event rate is crucial for their ability to test clinical hypotheses. Overestimation of event rates reduces the required sample size but can compromise the statistical power of the RCT. Little is known about the prevalence, extent, and impact of overestimation of event rates. The latest RCTs on 10 preselected topics in the field of cardiovascular interventions and devices were selected, and actual primary event rates in the control group were compared with their respective event rate estimations. We also assessed what proportion of the nonsignificant RCTs was truly able to exclude a relevant treatment effect. A total of 27 RCTs randomizing 19,436 patients were included. The primary event rate in the control group was overestimated in 20 of the 27 RCTs (74.1%) resulting in a substantial relative difference between observed and estimated event rates (mean -22.9%, 95% confidence interval -33.5% to -12.2%; median -16.3%, 95% confidence interval -30.3% to -6.5%). Event rates were particularly overestimated in RCTs on biodegradable polymer drug-eluting coronary stents and renal artery stenting. Of the 14 single end point superiority trials with nonsignificant results, only 3 (21.4%) actually resulted in truly negative conclusions. In conclusion, event rates in RCTs evaluating cardiovascular interventions and devices are frequently overestimated. This under-reported phenomenon has fundamental impact on the design of RCTs and can have an adverse impact on the statistical power of these trials to answer important questions about therapeutic strategies.

  5. Consideration of wear rates at high velocity

    NASA Astrophysics Data System (ADS)

    Hale, Chad S.

    The development of the research presented here is one in which high velocity relative sliding motion between two bodies in contact has been considered. Overall, the wear environment is truly three-dimensional. The attempt to characterize three-dimensional wear was not economically feasible because it must be analyzed at the micro-mechanical level to get results. Thus, an engineering approximation was carried out. This approximation was based on a metallographic study identifying the need to include viscoplasticity constitutive material models, coefficient of friction, relationships between the normal load and velocity, and the need to understand wave propagation. A sled test run at the Holloman High Speed Test Track (HHSTT) was considered for the determination of high velocity wear rates. In order to adequately characterize high velocity wear, it was necessary to formulate a numerical model that contained all of the physical events present. The experimental results of a VascoMax 300 maraging steel slipper sliding on an AISI 1080 steel rail during a January 2008 sled test mission were analyzed. During this rocket sled test, the slipper traveled 5,816 meters in 8.14 seconds and reached a maximum velocity of 1,530 m/s. This type of environment was never considered previously in terms of wear evaluation. Each of the features of the metallography were obtained through micro-mechanical experimental techniques. The byproduct of this analysis is that it is now possible to formulate a model that contains viscoplasticity, asperity collisions, temperature and frictional features. Based on the observations of the metallographic analysis, these necessary features have been included in the numerical model, which makes use of a time-dynamic program which follows the movement of a slipper during its experimental test run. The resulting velocity and pressure functions of time have been implemented in the explicit finite element code, ABAQUS. Two-dimensional, plane strain models

  6. High-Strain Rate Testing of Gun Propellants

    DTIC Science & Technology

    1988-12-01

    specimen is loaded beyond the elastic range. Instrumentation of the bars allows recording of the strain history in the bars during the test event. The...strain history on the input bar gives a record of the strain rate history in the sample. )The output bar strain history is proportional to the stress... history in the sample.) The data were compared to the results reported in the literature of earlier high strain rate tests on the same propellants. The

  7. Indoor acrolein emission and decay rates resulting from domestic cooking events

    NASA Astrophysics Data System (ADS)

    Seaman, Vincent Y.; Bennett, Deborah H.; Cahill, Thomas M.

    2009-12-01

    Acrolein (2-propenal) is a common constituent of both indoor and outdoor air, can exacerbate asthma in children, and may contribute to other chronic lung diseases. Recent studies have found high indoor levels of acrolein and other carbonyls compared to outdoor ambient concentrations. Heated cooking oils produce considerable amounts of acrolein, thus cooking is likely an important source of indoor acrolein. A series of cooking experiments were conducted to determine the emission rates of acrolein and other volatile carbonyls for different types of cooking oils (canola, soybean, corn and olive oils) and deep-frying different food items. Similar concentrations and emission rates of carbonyls were found when different vegetable oils were used to deep-fry the same food product. The food item being deep-fried was generally not a significant source of carbonyls compared to the cooking oil. The oil cooking events resulted in high concentrations of acrolein that were in the range of 26.4-64.5 μg m -3. These concentrations exceed all the chronic regulatory exposure limits and many of the acute exposure limits. The air exchange rate and the decay rate of the carbonyls were monitored to estimate the half-life of the carbonyls. The half-life for acrolein was 14.4 ± 2.6 h, which indicates that indoor acrolein concentrations can persist for considerable time after cooking in poorly-ventilated homes.

  8. Statistical Properties of SEE Rate Calculation in the Limits of Large and Small Event Counts

    NASA Technical Reports Server (NTRS)

    Ladbury, Ray

    2007-01-01

    This viewgraph presentation reviews the Statistical properties of Single Event Effects (SEE) rate calculations. The goal of SEE rate calculation is to bound the SEE rate, though the question is by how much. The presentation covers: (1) Understanding errors on SEE cross sections, (2) Methodology: Maximum Likelihood and confidence Contours, (3) Tests with Simulated data and (4) Applications.

  9. Understanding Ozark Forest Litter Variability Through a Synthesis of Accumulation Rates and Fire Events

    Treesearch

    Michael C. Stambaugh; Richard P. Guyette; Keith W. Grabner; Jeremy Kolaks

    2006-01-01

    Measuring success of fuels management is improved by understanding rates of litter accumulation and decay in relation to disturbance events. Despite the broad ecological importance of litter, little is known about the parameters of accumulation and decay rates in Ozark forests. Previously published estimates were used to derive accumulation rates and combined litter...

  10. Temporal and spatial variations of high-impact weather events in China during 1959-2014

    NASA Astrophysics Data System (ADS)

    Shi, Jun; Wen, Kangmin; Cui, Linli

    2017-07-01

    The variation and trend in the frequency and duration of four types of high-impact weather (HIW) events were examined using daily surface climate data and linear regression method, and results show that for both the frequency and the duration, the trends of hot weather events were not significant in most parts of China, though for the China as a whole, they had increased with rates of 0.4 days and 0.1 spells of hot weather per decade respectively. The frequency of cold weather events had decreased significantly in most parts of China, particularly in northern, northeastern, and western China, where it increased at rates of 2-8 days per decade in most stations, but the duration of cold weather events were not significant in most parts of China. The frequency of gale weather events had decreased in almost all of China, with a rate of 3.7 days per decade for the China as a whole, and the duration of gale weather events had decreased mainly in northeastern and northern China, western Xinjiang, southwestern Sichuan, and some coastal areas of Liaoning, Shandong, Zhejiang, and Fujian. The frequency of rainstorm weather events was not significant in most parts of China, and the duration of rainstorm weather events was not significant in the whole of China. With global climate change, there would be an increase in the hot and rainstorm weather events, so mitigation/adaptation strategies for such weather events are essential for local government and social public.

  11. Temporal and spatial variations of high-impact weather events in China during 1959-2014

    NASA Astrophysics Data System (ADS)

    Shi, Jun; Wen, Kangmin; Cui, Linli

    2016-04-01

    The variation and trend in the frequency and duration of four types of high-impact weather (HIW) events were examined using daily surface climate data and linear regression method, and results show that for both the frequency and the duration, the trends of hot weather events were not significant in most parts of China, though for the China as a whole, they had increased with rates of 0.4 days and 0.1 spells of hot weather per decade respectively. The frequency of cold weather events had decreased significantly in most parts of China, particularly in northern, northeastern, and western China, where it increased at rates of 2-8 days per decade in most stations, but the duration of cold weather events were not significant in most parts of China. The frequency of gale weather events had decreased in almost all of China, with a rate of 3.7 days per decade for the China as a whole, and the duration of gale weather events had decreased mainly in northeastern and northern China, western Xinjiang, southwestern Sichuan, and some coastal areas of Liaoning, Shandong, Zhejiang, and Fujian. The frequency of rainstorm weather events was not significant in most parts of China, and the duration of rainstorm weather events was not significant in the whole of China. With global climate change, there would be an increase in the hot and rainstorm weather events, so mitigation/adaptation strategies for such weather events are essential for local government and social public.

  12. Relationship between medication event rates and the Leapfrog computerized physician order entry evaluation tool

    PubMed Central

    Leung, Alexander A; Keohane, Carol; Lipsitz, Stuart; Zimlichman, Eyal; Amato, Mary; Simon, Steven R; Coffey, Michael; Kaufman, Nathan; Cadet, Bismarck; Schiff, Gordon; Seger, Diane L; Bates, David W

    2013-01-01

    Objective The Leapfrog CPOE evaluation tool has been promoted as a means of monitoring computerized physician order entry (CPOE). We sought to determine the relationship between Leapfrog scores and the rates of preventable adverse drug events (ADE) and potential ADE. Materials and methods A cross-sectional study of 1000 adult admissions in five community hospitals from October 1, 2008 to September 30, 2010 was performed. Observed rates of preventable ADE and potential ADE were compared with scores reported by the Leapfrog CPOE evaluation tool. The primary outcome was the rate of preventable ADE and the secondary outcome was the composite rate of preventable ADE and potential ADE. Results Leapfrog performance scores were highly related to the primary outcome. A 43% relative reduction in the rate of preventable ADE was predicted for every 5% increase in Leapfrog scores (rate ratio 0.57; 95% CI 0.37 to 0.88). In absolute terms, four fewer preventable ADE per 100 admissions were predicted for every 5% increase in overall Leapfrog scores (rate difference −4.2; 95% CI −7.4 to −1.1). A statistically significant relationship between Leapfrog scores and the secondary outcome, however, was not detected. Discussion Our findings support the use of the Leapfrog tool as a means of evaluating and monitoring CPOE performance after implementation, as addressed by current certification standards. Conclusions Scores from the Leapfrog CPOE evaluation tool closely relate to actual rates of preventable ADE. Leapfrog testing may alert providers to potential vulnerabilities and highlight areas for further improvement. PMID:23599225

  13. Variety Is Not the Spice of Life for People with Autism Spectrum Disorders: Frequency Ratings of Central, Variable and Inappropriate Aspects of Common Real-Life Events

    ERIC Educational Resources Information Center

    Loth, Eva; Happe, Francesca; Gomez, Juan Carlos

    2010-01-01

    This study used a novel rating task to investigate whether high-functioning individuals with autism spectrum disorder (ASD) have difficulties distinguishing essential from variable aspects of familiar events. Participants read stories about everyday events and judged how often central, variable, and inappropriate event-components normally occur in…

  14. Variety Is Not the Spice of Life for People with Autism Spectrum Disorders: Frequency Ratings of Central, Variable and Inappropriate Aspects of Common Real-Life Events

    ERIC Educational Resources Information Center

    Loth, Eva; Happe, Francesca; Gomez, Juan Carlos

    2010-01-01

    This study used a novel rating task to investigate whether high-functioning individuals with autism spectrum disorder (ASD) have difficulties distinguishing essential from variable aspects of familiar events. Participants read stories about everyday events and judged how often central, variable, and inappropriate event-components normally occur in…

  15. Sufficient dimension reduction on the mean and rate functions of recurrent events.

    PubMed

    Zhao, Xiaobing; Zhou, Xian

    2014-09-20

    The counting process with a Cox-type intensity function has been extensively applied to analyze recurrent event data, which assume that the underlying counting process is a time-transformed Poisson process and that the covariates have multiplicative or additive effects on the mean and rate functions of the counting process. The existing statistical inference, however, often encounters difficulties due to high-dimensional covariates, such as in gene expression and single nucleotide polymorphism data that have revolutionized our understanding of cancer recurrence and other diseases. In this paper, a technique of sufficient dimension reduction is applied to the mean and rate function for the number of occurrences of events over time. A two-step procedure is proposed to estimate the model components: first, a nonparametric estimator is proposed for the baseline, and then the basis of the central subspace and its dimension are estimated through a modified slicing inverse regression. On the basis of the estimated structural dimension and on the basis of the central subspace, we can estimate the regression function by using the local linear regression. A simulation is performed to confirm and assess the theoretical findings, and an application is demonstrated on a set of chronic granulomatous disease data. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Meta-analysis of safety for low event-rate binomial trials.

    PubMed

    Shuster, Jonathan J; Guo, Jennifer D; Skyler, Jay S

    2012-03-01

    This article focuses on meta-analysis of low event-rate binomial trials. We introduce two forms of random effects: (1) 'studies at random' (SR), where we assume no more than independence between studies; and (2) 'effects at random' (ER), which forces the effect size distribution to be independent of the study design. On the basis of the summary estimates of proportions, we present both unweighted and study-size weighted methods, which, under SR, target different population parameters. We demonstrate mechanistically that the popular DerSimonian-Laird (DL) method, as DL actually warned in their paper, should never be used in this setting. We conducted a survey of the major cardiovascular literature on low event-rate studies and found that DL using odds ratios or relative risks to be the clear method of choice. We looked at two high profile examples from diabetes and cancer, respectively, where the choice of weighted versus unweighted methods makes a large difference. A large simulation study supports the accuracy of the coverage of our approximate confidence intervals. We recommend that before looking at their data, users should prespecify which target parameter they intend to estimate (weighted vs. unweighted) but estimate the other as a secondary analysis. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.

  17. Meta-analysis of safety for low event-rate binomial trials

    PubMed Central

    Shuster, Jonathan J; Guo, Jennifer D.; Skyler, Jay S.

    2013-01-01

    SUMMARY This article focuses on meta-analysis of low event-rate binomial trials. We introduce two forms of random effects: (1) “Studies at Random” (SR), where we assume no more than independence between studies; and (2) “Effects at random” (ER), which forces the effect size distribution to be independent of the study design. Based upon summary estimates of proportions, we present both unweighted and study size weighted methods, which under SR target different population parameters. We demonstrate mechanistically that the popular DerSimonian-Laird (DL) method, as DL actually warned in their paper, should never be used in this setting. We conducted a survey of the major cardiovascular literature on low event rate studies and found that DL using odds ratios or relative risks to be the clear method of choice. We looked at two high profile examples from diabetes and cancer, respectively, where the choice of weighted vs. unweighted methods makes a large difference. A large simulation study supports the accuracy of coverage of our approximate confidence intervals. We recommend that before looking at their data, users should pre-specify which target parameter they intend to estimate (weighted vs. unweighted), but estimate the other as a secondary analysis. PMID:24339834

  18. The single event upset environment for avionics at high latitude

    SciTech Connect

    Sims, A.J.; Dyer, C.S.; Peerless, C.L. . Space and Communications Dept.); Johansson, K.; Pettersson, H. ); Farren, J. . Harwell Lab.)

    1994-12-01

    Modern avionic systems for civil and military applications are becoming increasingly reliant upon embedded microprocessors and associated memory devices. The phenomenon of single event upset (SEU) is well known in space systems and designers have generally been careful to use SEU tolerant devices or to implement error detection and correction (EDAC) techniques where appropriate. In the past, avionics designers have had no reason to consider SEU effects but is clear that the more prevalent use of memory devices combined with increasing levels of IC integration will make SEU mitigation an important design consideration for future avionic systems. To this end, it is necessary to work towards producing models of the avionics SEU environment which will permit system designers to choose components and EDAC techniques which are based on predictions of SEU rates correct to much better than an order of magnitude. Measurements of the high latitude SEU environment at avionics altitude have been made on board a commercial airliner. Results are compared with models of primary and secondary cosmic rays and atmospheric neutrons. Ground based SEU tests of static RAMs are used to predict rates in flight.

  19. Diamond detector for high rate monitors of fast neutrons beams

    SciTech Connect

    Giacomelli, L.; Rebai, M.; Cippo, E. Perelli; Tardocchi, M.; Fazzi, A.; Andreani, C.; Pietropaolo, A.; Frost, C. D.; Rhodes, N.; Schooneveld, E.; Gorini, G.

    2012-06-19

    A fast neutron detection system suitable for high rate measurements is presented. The detector is based on a commercial high purity single crystal diamond (SDD) coupled to a fast digital data acquisition system. The detector was tested at the ISIS pulsed spallation neutron source. The SDD event signal was digitized at 1 GHz to reconstruct the deposited energy (pulse amplitude) and neutron arrival time; the event time of flight (ToF) was obtained relative to the recorded proton beam signal t{sub 0}. Fast acquisition is needed since the peak count rate is very high ({approx}800 kHz) due to the pulsed structure of the neutron beam. Measurements at ISIS indicate that three characteristics regions exist in the biparametric spectrum: i) background gamma events of low pulse amplitudes; ii) low pulse amplitude neutron events in the energy range E{sub dep}= 1.5-7 MeV ascribed to neutron elastic scattering on {sup 12}C; iii) large pulse amplitude neutron events with E{sub n} < 7 MeV ascribed to {sup 12}C(n,{alpha}){sup 9}Be and 12C(n,n')3{alpha}.

  20. Galactic Distribution of Planets From High-Magnification Microlensing Events

    NASA Astrophysics Data System (ADS)

    Gould, Andrew; Yee, Jennifer; Carey, Sean

    2015-10-01

    We will use Spitzer to measure microlens parallaxes for ~14 microlensing events that are high-magnification (as seen from Earth), in order to determine the Galactic distribution of planets. Simultaneous observations from Spitzer and Earth yield parallaxes because they are separated by ~1 AU, which is of order the size of the Einstein radius projected on the observer plane. Hence, Earth and Spitzer see substantially different lightcurves for the same event. These Spitzer parallaxes enable measurements of the distances to the lenses (and their masses), which is a crucial element for measuring the Galactic distribution of planets. High-mag events are exceptionally sensitive to planets: Gould+ (2010) detected 6 planets from 13 high-mag events. However, previously it was believed impossible to measure their parallaxes using Spitzer: scheduling constraints imply a 3-10 day delay from event recognition to first observation, while high-mag events are typically recognized only 1-2 days before peak. By combining aggressive observing protocols, a completely new photometry pipeline, and new mathematical techniques, we successfully measured parallaxes for 7 events with peak magnification A>100 and another ~7 with 50high-mag events. From this sample, we expect to detect ~4 planets (the number is smaller than Gould+ 2010 because our Spitzer sample will have lower mean magnification). These ~4 planets represent significant progress toward the ~12 necessary to measure the Galactic distribution. All lightcurves will be reduced using our customized software and then made public (unrestricted use), within 2 months of the completion of observations (as we did for our 2015 observations).

  1. Consequence Prioritization Process for Potential High Consequence Events (HCE)

    SciTech Connect

    Freeman, Sarah G.

    2016-10-31

    This document describes the process for Consequence Prioritization, the first phase of the Consequence-Driven Cyber-Informed Engineering (CCE) framework. The primary goal of Consequence Prioritization is to identify potential disruptive events that would significantly inhibit an organization’s ability to provide the critical services and functions deemed fundamental to their business mission. These disruptive events, defined as High Consequence Events (HCE), include both events that have occurred or could be realized through an attack of critical infrastructure owner assets. While other efforts have been initiated to identify and mitigate disruptive events at the national security level, such as Presidential Policy Directive 41 (PPD-41), this process is intended to be used by individual organizations to evaluate events that fall below the threshold for a national security. Described another way, Consequence Prioritization considers threats greater than those addressable by standard cyber-hygiene and includes the consideration of events that go beyond a traditional continuity of operations (COOP) perspective. Finally, Consequence Prioritization is most successful when organizations adopt a multi-disciplinary approach, engaging both cyber security and engineering expertise, as in-depth engineering perspectives are required to recognize and characterize and mitigate HCEs. Figure 1 provides a high-level overview of the prioritization process.

  2. Achieving High Resolution Timer Events in Virtualized Environment.

    PubMed

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs-Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service). Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events.

  3. Structure of turbulence at high shear rate

    NASA Technical Reports Server (NTRS)

    Lee, Moon Joo; Kim, John; Moin, Parviz

    1990-01-01

    The structure of homogeneous turbulence subject to high shear rate has been investigated by using three-dimensional, time-dependent numerical simulations of the Navier-Stokes equations. This study indicates that high shear rate alone is sufficient for generation of the streaky structures, and that the presence of a solid boundary is not necessary. Evolution of the statistical correlations is examined to determine the effect of high shear rate on the development of anisotropy in turbulence. It is shown that the streamwise fluctuating motions are enhanced so profoundly that a highly anisotropic turbulence state with a 'one-component' velocity field and 'two-component' vorticity field develops asymptotically as total shear increases. Because of high-shear rate, rapid distortion theory predicts remarkably well the anisotropic behavior of the structural quantities.

  4. High burn rate solid composite propellants

    NASA Astrophysics Data System (ADS)

    Manship, Timothy D.

    High burn rate propellants help maintain high levels of thrust without requiring complex, high surface area grain geometries. Utilizing high burn rate propellants allows for simplified grain geometries that not only make production of the grains easier, but the simplified grains tend to have better mechanical strength, which is important in missiles undergoing high-g accelerations. Additionally, high burn rate propellants allow for a higher volumetric loading which reduces the overall missile's size and weight. The purpose of this study is to present methods of achieving a high burn rate propellant and to develop a composite propellant formulation that burns at 1.5 inches per second at 1000 psia. In this study, several means of achieving a high burn rate propellant were presented. In addition, several candidate approaches were evaluated using the Kepner-Tregoe method with hydroxyl terminated polybutadiene (HTPB)-based propellants using burn rate modifiers and dicyclopentadiene (DCPD)-based propellants being selected for further evaluation. Propellants with varying levels of nano-aluminum, nano-iron oxide, FeBTA, and overall solids loading were produced using the HTPB binder and evaluated in order to determine the effect the various ingredients have on the burn rate and to find a formulation that provides the burn rate desired. Experiments were conducted to compare the burn rates of propellants using the binders HTPB and DCPD. The DCPD formulation matched that of the baseline HTPB mix. Finally, GAP-plasticized DCPD gumstock dogbones were attempted to be made for mechanical evaluation. Results from the study show that nano-additives have a substantial effect on propellant burn rate with nano-iron oxide having the largest influence. Of the formulations tested, the highest burn rate was a 84% solids loading mix using nano-aluminum nano-iron oxide, and ammonium perchlorate in a 3:1(20 micron: 200 micron) ratio which achieved a burn rate of 1.2 inches per second at 1000

  5. Safety Events in High Risk Prehospital Neonatal Calls.

    PubMed

    Duby, Rebecca; Hansen, Matt; Meckler, Garth; Skarica, Barbara; Lambert, William; Guise, Jeanne-Marie

    2017-08-31

    The objective of this study was to quantify and characterize patient safety events during high-risk neonatal transports in the prehospital setting. We conducted a retrospective chart review of all "lights and sirens" ambulance transports of neonates ≤30 days old over a four-year period in a metropolitan area. Each case was independently reviewed for potential patient safety events that may have occurred in clinical assessment and decision making, resuscitation, airway management, fluid or medication administration, procedures performed, and/or equipment used. Twenty-six patients ≤30 days old were transported by ambulance using lights and sirens during the four-year study period. Overall, safety events occurred in 19 patients and severe safety events (potentially causing permanent injury or harm, including death) occurred in ten. The incidence of safety events related to medication administrations was 90% (70% severe), resuscitation 64.7% (47.1% severe), procedures 64.7% (35.3% severe), fluid administration 50% (25% severe), clinical assessment and decision making 50% (30.8% severe), airway management 47.6% (28.6% severe), equipment use 25.5% (10.0% severe), and systems processes 19.2% (7.7% severe). High-risk neonatal calls are infrequent and prone to a high incidence of serious patient safety events.

  6. Three-year follow-up and event rates in the international REduction of Atherothrombosis for Continued Health Registry.

    PubMed

    Alberts, Mark J; Bhatt, Deepak L; Mas, Jean-Louis; Ohman, E Magnus; Hirsch, Alan T; Röther, Joachim; Salette, Geneviève; Goto, Shinya; Smith, Sidney C; Liau, Chiau-Suong; Wilson, Peter W F; Steg, Ph Gabriel

    2009-10-01

    To determine 3-year event rates in outpatients with vascular disease enrolled in the REduction of Atherothrombosis for Continued Health (REACH) Registry. REACH enrolled 67 888 outpatients with atherothrombosis [established coronary artery disease (CAD), cerebrovascular disease, or peripheral arterial disease (PAD)], or with at least three atherothrombotic risk factors, from 44 countries. Among the 55 499 patients at baseline with symptomatic disease, 39 675 were eligible for 3-year follow-up, and 32 247 had data available (81% retention rate). Among the symptomatic patients at 3 years, 92% were taking an antithrombotic agent, 91% an antihypertensive, and 76% were on lipid-lowering therapy. For myocardial infarction (MI)/stroke/vascular death, 1- and 3-year event rates for all patients were 4.2 and 11.0%, respectively. Event rates (MI/stroke/vascular death) were significantly higher for patients with symptomatic disease vs. those with risk factors only at 1 year (4.7 vs. 2.3%, P < 0.001) and at 3 years (12.0 vs. 6.0%, P < 0.001). One and 3-year rates of MI/stroke/vascular death/rehospitalization were 14.4 and 28.4%, respectively, for patients with symptomatic disease. Rehospitalization for a vascular event other than MI/stroke/vascular death was common at 3 years (19.0% overall; 33.6% for PAD; 23.0% for CAD). For patients with symptomatic vascular disease in one vascular bed vs. multiple vascular beds, 3-year event rates for MI/stroke/vascular death/rehospitalization were 25.5 vs. 40.5% (P < 0.001). Despite contemporary therapy, outpatients with symptomatic atherothrombotic vascular disease experience high rates of recurrent vascular events and rehospitalizations.

  7. Three-year follow-up and event rates in the international REduction of Atherothrombosis for Continued Health Registry

    PubMed Central

    Alberts, Mark J.; Bhatt, Deepak L.; Mas, Jean-Louis; Ohman, E. Magnus; Hirsch, Alan T.; Röther, Joachim; Salette, Geneviève; Goto, Shinya; Smith, Sidney C.; Liau, Chiau-Suong; Wilson, Peter W.F.; Steg, Ph. Gabriel

    2009-01-01

    Aims To determine 3-year event rates in outpatients with vascular disease enrolled in the REduction of Atherothrombosis for Continued Health (REACH) Registry. Methods and results REACH enrolled 67 888 outpatients with atherothrombosis [established coronary artery disease (CAD), cerebrovascular disease, or peripheral arterial disease (PAD)], or with at least three atherothrombotic risk factors, from 44 countries. Among the 55 499 patients at baseline with symptomatic disease, 39 675 were eligible for 3-year follow-up, and 32 247 had data available (81% retention rate). Among the symptomatic patients at 3 years, 92% were taking an antithrombotic agent, 91% an antihypertensive, and 76% were on lipid-lowering therapy. For myocardial infarction (MI)/stroke/vascular death, 1- and 3-year event rates for all patients were 4.2 and 11.0%, respectively. Event rates (MI/stroke/vascular death) were significantly higher for patients with symptomatic disease vs. those with risk factors only at 1 year (4.7 vs. 2.3%, P < 0.001) and at 3 years (12.0 vs. 6.0%, P < 0.001). One and 3-year rates of MI/stroke/vascular death/rehospitalization were 14.4 and 28.4%, respectively, for patients with symptomatic disease. Rehospitalization for a vascular event other than MI/stroke/vascular death was common at 3 years (19.0% overall; 33.6% for PAD; 23.0% for CAD). For patients with symptomatic vascular disease in one vascular bed vs. multiple vascular beds, 3-year event rates for MI/stroke/vascular death/rehospitalization were 25.5 vs. 40.5% (P < 0.001). Conclusion Despite contemporary therapy, outpatients with symptomatic atherothrombotic vascular disease experience high rates of recurrent vascular events and rehospitalizations. PMID:19720633

  8. Forecasting Dose Rate from a Solar Particle Event Using Localized Weighted Regression

    NASA Astrophysics Data System (ADS)

    Nichols, Theodore; Hines, J. W.; Townsend, Lawrence W.; Neal, John

    Predicting the dose rate from a Solar Particle Event (SPE) is important to provide adequate warning to astronauts. Dose from an SPE can be large enough to produce either stochastic or deterministic effects. Localized weighted regression (LWR) is the model being used to forecast the dose and the temporal profile from an SPE. LWR is a non-parametric memory based technique; it compares a new query to stored sets of exemplar data to make its predictions. The only input into the system is dose readings from a dosimeter. Allowing the method to provide forecasts anywhere in the solar system. LWR is able to forecast early in an SPE the dose rate for the event. For many events the total dose is predicted within a factor of two within 20 minutes of the event beginning. SPEs that are within the training parameters have temporal predictions within a few hours of the start of the event. Using a LWR model, forecasts of dose rate are able to be made a few hours after the start of the event. Most types of events the model is able to forecast within about 10

  9. High-rate lithium thionyl chloride cells

    NASA Technical Reports Server (NTRS)

    Goebel, F.

    1982-01-01

    A high-rate C cell with disc electrodes was developed to demonstrate current rates which are comparable to other primary systems. The tests performed established the limits of abuse beyond which the cell becomes hazardous. Tests include: impact, shock, and vibration tests; temperature cycling; and salt water immersion of fresh cells.

  10. Multichannel analyzers at high rates of input

    NASA Technical Reports Server (NTRS)

    Rudnick, S. J.; Strauss, M. G.

    1969-01-01

    Multichannel analyzer, used with a gating system incorporating pole-zero compensation, pile-up rejection, and baseline-restoration, achieves good resolution at high rates of input. It improves resolution, reduces tailing and rate-contributed continuum, and eliminates spectral shift.

  11. Deconvolution of high rate flicker electroretinograms.

    PubMed

    Alokaily, A; Bóhorquez, J; Özdamar, Ö

    2014-01-01

    Flicker electroretinograms are steady-state electroretinograms (ERGs) generated by high rate flash stimuli that produce overlapping periodic responses. When a flash stimulus is delivered at low rates, a transient response named flash ERG (FERG) representing the activation of neural structures within the outer retina is obtained. Although FERGs and flicker ERGs are used in the diagnosis of many retinal diseases, their waveform relationships have not been investigated in detail. This study examines this relationship by extracting transient FERGs from specially generated quasi steady-state flicker and ERGs at stimulation rates above 10 Hz and similarly generated conventional flicker ERGs. The ability to extract the transient FERG responses by deconvolving flicker responses to temporally jittered stimuli at high rates is investigated at varying rates. FERGs were obtained from seven normal subjects stimulated with LED-based displays, delivering steady-state and low jittered quasi steady-state responses at five rates (10, 15, 32, 50, 68 Hz). The deconvolution method enabled a successful extraction of "per stimulus" unit transient ERG responses for all high stimulation rates. The deconvolved FERGs were used successfully to synthesize flicker ERGs obtained at the same high stimulation rates.

  12. ISS Update: High Rate Communications System

    NASA Image and Video Library

    ISS Update Commentator Pat Ryan interviews Diego Serna, Communications and Tracking Officer, about the High Rate Communications System. Questions? Ask us on Twitter @NASA_Johnson and include the ha...

  13. The influence of disturbance events on survival and dispersal rates of Florida box turtles.

    PubMed

    Dodd, C Kenneth; Ozgul, Arpat; Oli, Madan K

    2006-10-01

    Disturbances have the potential to cause long-term effects to ecosystem structure and function, and they may affect individual species in different ways. Long-lived vertebrates such as turtles may be at risk from such events, inasmuch as their life histories preclude rapid recovery should extensive mortality occur. We applied capture-mark-recapture models to assess disturbance effects on a population of Florida box turtles (Terrapene carolina bauri) on Egmont Key, Florida, USA. Near the midpoint of the study, a series of physical disturbances affected the island, from salt water overwash associated with several tropical storms to extensive removal of nonindigenous vegetation. These disturbances allowed us to examine demographic responses of the turtle population and to determine if they affected dispersal throughout the island. Adult survival rates did not vary significantly either between sexes or among years of the study. Survival rates did not vary significantly between juvenile and adult turtles, or among years of the study. Furthermore, neither adult nor juvenile survival rates differed significantly between pre- and post-disturbance. However, dispersal rates varied significantly among the four major study sites, and dispersal rates were higher during the pre-disturbance sampling periods compared to post-disturbance. Our results suggest few long-term effects on the demography of the turtle population. Florida box turtles responded to tropical storms and vegetation control by moving to favorable habitats minimally affected by the disturbances and remaining there. As long as turtles and perhaps other long-lived vertebrates can disperse to non-disturbed habitat, and high levels of mortality do not occur in a population, a long life span may allow them to wait out the impact of disturbance with potentially little effect on long-term population processes.

  14. The influence of disturbance events on survival and dispersal rates of Florida box turtles

    USGS Publications Warehouse

    Dodd, C.K.; Ozgul, A.; Oli, M.K.

    2006-01-01

    Disturbances have the potential to cause long-term effects to ecosystem structure and function, and they may affect individual species in different ways. Long-lived vertebrates such as turtles may be at risk from such events, inasmuch as their life histories preclude rapid recovery should extensive mortality occur. We applied capture–mark–recapture models to assess disturbance effects on a population of Florida box turtles (Terrapene carolina bauri) on Egmont Key, Florida, USA. Near the midpoint of the study, a series of physical disturbances affected the island, from salt water overwash associated with several tropical storms to extensive removal of nonindigenous vegetation. These disturbances allowed us to examine demographic responses of the turtle population and to determine if they affected dispersal throughout the island. Adult survival rates did not vary significantly either between sexes or among years of the study. Survival rates did not vary significantly between juvenile and adult turtles, or among years of the study. Furthermore, neither adult nor juvenile survival rates differed significantly between pre- and post-disturbance. However, dispersal rates varied significantly among the four major study sites, and dispersal rates were higher during the pre-disturbance sampling periods compared to post-disturbance. Our results suggest few long-term effects on the demography of the turtle population. Florida box turtles responded to tropical storms and vegetation control by moving to favorable habitats minimally affected by the disturbances and remaining there. As long as turtles and perhaps other long-lived vertebrates can disperse to non-disturbed habitat, and high levels of mortality do not occur in a population, a long life span may allow them to wait out the impact of disturbance with potentially little effect on long-term population processes.

  15. Turbulence structure at high shear rate

    NASA Technical Reports Server (NTRS)

    Lee, Moon Joo; Kim, John; Moin, Parviz

    1987-01-01

    The structure of homogeneous turbulence in the presence of a high shear rate is studied using results obtained from three-dimensional time-dependent numerical simulations of the Navier-Stokes equations on a grid of 512 x 128 x 128 node points. It is shown that high shear rate enhances the streamwise fluctuating motion to such an extent that a highly anisotropic turbulence state with a one-dimensional velocity field and two-dimensional small-scale turbulence develops asymptotically as total shear increases. Instantaneous velocity fields show that high shear rate in homogeneous turbulent shear flow produces structures which are similar to the streaks present in the viscous sublayer of turbulent boundary layers.

  16. Ultra High Strain Rate Nanoindentation Testing.

    PubMed

    Sudharshan Phani, Pardhasaradhi; Oliver, Warren Carl

    2017-06-17

    Strain rate dependence of indentation hardness has been widely used to study time-dependent plasticity. However, the currently available techniques limit the range of strain rates that can be achieved during indentation testing. Recent advances in electronics have enabled nanomechanical measurements with very low noise levels (sub nanometer) at fast time constants (20 µs) and high data acquisition rates (100 KHz). These capabilities open the doors for a wide range of ultra-fast nanomechanical testing, for instance, indentation testing at very high strain rates. With an accurate dynamic model and an instrument with fast time constants, step load tests can be performed which enable access to indentation strain rates approaching ballistic levels (i.e., 4000 1/s). A novel indentation based testing technique involving a combination of step load and constant load and hold tests that enables measurement of strain rate dependence of hardness spanning over seven orders of magnitude in strain rate is presented. A simple analysis is used to calculate the equivalent uniaxial response from indentation data and compared to the conventional uniaxial data for commercial purity aluminum. Excellent agreement is found between the indentation and uniaxial data over several orders of magnitude of strain rate.

  17. Heart rate response to "off-road" running events in female athletes

    PubMed Central

    Creagh, U.; Reilly, T.; Nevill, A. M.

    1998-01-01

    INTRODUCTION: Despite the growing popularity of off-road running events, little information is available about the physiological stress of such activities. The demands of such events are unique in terms of the rough surface of the terrain encountered as well as the underfoot vegetation and the gradient. OBJECTIVES: The aim of this study was to investigate the physiological response of female athletes, as measured by heart rate, to three common off-road running events: cross country running (n = 15), fell running (n = 20), and orienteering (n = 25). METHODS: Heart rate responses were recorded during cross country and fell races, and orienteering by means of short range radiotelemetry. Road running (n = 21) was also studied as a reference. RESULTS: The mean heart rates for each event varied with the differing demands of the terrain. The highest (182 (10) beats/minute; mean (SD)) was for road running and the lowest (172 (10) beats/minute) for orienteering. Orienteering evoked a significantly more variable response than all other events (F4,100 = 112.4; p<0.01), with a range of 44 beats/minute (142-186 beats/minute) in the heart rate. This may be due to both the variability of the terrain and the additional technical aspect of this sport. There was a positive trend in the slope of the regression lines of heart rate against time for both road and cross country running, which was not evident in the fell runners or the orienteers. The latter events demonstrated no consistent pattern. CONCLUSIONS: It is concluded that running off-road elicits a heart rate response that varies with the altering demands of surface, vegetation, and gradient. 


 PMID:9562161

  18. Thrombus Formation at High Shear Rates.

    PubMed

    Casa, Lauren D C; Ku, David N

    2017-06-21

    The final common pathway in myocardial infarction and ischemic stroke is occlusion of blood flow from a thrombus forming under high shear rates in arteries. A high-shear thrombus forms rapidly and is distinct from the slow formation of coagulation that occurs in stagnant blood. Thrombosis at high shear rates depends primarily on the long protein von Willebrand factor (vWF) and platelets, with hemodynamics playing an important role in each stage of thrombus formation, including vWF binding, platelet adhesion, platelet activation, and rapid thrombus growth. The prediction of high-shear thrombosis is a major area of biofluid mechanics in which point-of-care testing and computational modeling are promising future directions for clinically relevant research. Further research in this area will enable identification of patients at high risk for arterial thrombosis, improve prevention and treatment based on shear-dependent biological mechanisms, and improve blood-contacting device design to reduce thrombosis risk.

  19. Size, duration, and rate of growth of nocturnal lightning events appearing on space shuttle video tapes

    NASA Technical Reports Server (NTRS)

    Breslawski, Christine

    1990-01-01

    An analysis of video tapes of nocturnal lightning events, taken aboard space shuttle flights STS-8, STS-9, STS-41D, and STS-51J, shows flashes with dimensions ranging from approximately 1 km by 1 km to 440 km by 110 km. Of particular interest are the flashes whose dimensions exceeded 100 km, as flashes of this size are seldom reported. In general, larger flashes were found to have longer durations, take longer to reach their maximum extent, and reach their maximum extent at a smaller percent of their total duration than smaller flashes. Sixty four percent of the flashes occurred with one to five other events appearing in the same video frame. These simultaneous events were an average of 60 km apart from each other. If a breakdown process is propagating between the simultaneous flashes, it would be travelling at a rate of 10(exp 5)m/sec. Plots of the area of an event over its duration show peaks in the area curve which may be indicative if lightning strokes. There was an average of 3.6 peaks per flash. In general, the longer the flash duration, the more peaks there were in the area curve. The area curves of the lightning events fall into one of five shape categories. It is suggested that the shape of the area curve may indicate whether an event is an intracloud or cloud to ground lightning flash. Some of the lightning events had a persistent bright spot. These events had an average duration which was greater than that of events without the bright spot. On average, the bright spot events had a maximum area which was larger than that of the flashes without the bright spot.

  20. High Bit Rate Experiments Over ACTS

    NASA Technical Reports Server (NTRS)

    Bergman, Larry A.; Gary, J. Patrick; Edelsen, Burt; Helm, Neil; Cohen, Judith; Shopbell, Patrick; Mechoso, C. Roberto; Chung-Chun; Farrara, M.; Spahr, Joseph

    1996-01-01

    This paper describes two high data rate experiments chat are being developed for the gigabit NASA Advanced Communications Technology Satellite (ACTS). The first is a telescience experiment that remotely acquires image data at the Keck telescope from the Caltech campus. The second is a distributed global climate application that is run between two supercomputer centers interconnected by ACTS. The implementation approach for each is described along with the expected results. Also. the ACTS high data rate (HDR) ground station is also described in detail.

  1. High Bit Rate Experiments Over ACTS

    NASA Technical Reports Server (NTRS)

    Bergman, Larry A.; Gary, J. Patrick; Edelsen, Burt; Helm, Neil; Cohen, Judith; Shopbell, Patrick; Mechoso, C. Roberto; Chung-Chun; Farrara, M.; Spahr, Joseph

    1996-01-01

    This paper describes two high data rate experiments chat are being developed for the gigabit NASA Advanced Communications Technology Satellite (ACTS). The first is a telescience experiment that remotely acquires image data at the Keck telescope from the Caltech campus. The second is a distributed global climate application that is run between two supercomputer centers interconnected by ACTS. The implementation approach for each is described along with the expected results. Also. the ACTS high data rate (HDR) ground station is also described in detail.

  2. High Amplitude Events in relation to Interplanetary disturbances

    NASA Astrophysics Data System (ADS)

    Mishra, Rajesh Kumar; Agarwal Mishra, Rekha

    2012-07-01

    The Sun emits the variable solar wind which interacts with the very local interstellar medium to form the heliosphere. Hence variations in solar activity strongly influence interplanetary space, from the Sun's surface out to the edge of the heliosphere. Superimposed on the solar wind are mass ejections from the Sun and/or its corona which, disturb the interplanetary medium - hence the name "interplanetary disturbances". Interplanetary disturbances are the sources of large-scale particle acceleration, of disturbances in the Earth's magnetosphere, of modulations of galactic cosmic rays in short, they are the prime focus for space weather studies. The investigation deals with the study of cosmic ray intensity, solar wind plasma and interplanetary magnetic field parameters variation due to interplanetary disturbances (magnetic clouds) during an unusual class of days i.e. high amplitude anisotropic wave train events. The high amplitude anisotropic wave train events in cosmic ray intensity has been identified using the data of ground based Goose Bay neutron monitor and studied during the period 1981-94. Even though, the occurrence of high amplitude anisotropic wave trains does not depend on the onset of interplanetary magnetic clouds. But the possibility of occurrence of these events cannot be overlooked during the periods of interplanetary magnetic cloud events. It is observed that solar wind velocity remains higher (> 300) than normal and interplanetary magnetic field B remains lower than normal on the onset of interplanetary magnetic cloud during the passage of these events. It is also noted from the superposed epoch analysis of cosmic ray intensity and geomagnetic activity for high amplitude anisotropic wave train events during the onset of interplanetary magnetic clouds that the increase in cosmic ray intensity and decrease in geomagnetic activity start not at the onset of magnetic clouds but after few days. The north south component of IMF (Bz), IMF (B), proton

  3. TMF ultra-high rate discharge performance

    SciTech Connect

    Nelson, B.

    1997-12-01

    BOLDER Technologies Corporation has developed a valve-regulated lead-acid product line termed Thin Metal Film (TMF{trademark}) technology. It is characterized by extremely thin plates and close plate spacing that facilitate high rates of charge and discharge with minimal temperature increases, at levels unachievable with other commercially-available battery technologies. This ultra-high rate performance makes TMF technology ideal for such applications as various types of engine start, high drain rate portable devices and high-current pulsing. Data are presented on very high current continuous and pulse discharges. Power and energy relationships at various discharge rates are explored and the fast-response characteristics of the BOLDER{reg_sign} cell are qualitatively defined. Short-duration recharge experiments will show that devices powered by BOLDER batteries can be in operation for more than 90% of an extended usage period with multiple fast recharges. The BOLDER cell is ideal for applications such as engine-start, a wide range of portable devices including power tools, hybrid electric vehicles and pulse-power devices. Applications such as this are very attractive, and are well served by TMF technology, but an area of great interest and excitement is ultrahigh power delivery in excess of 1 kW/kg.

  4. High Resolution Modeling of Tropical Cyclones Using Rare Event Simulation

    NASA Astrophysics Data System (ADS)

    Plotkin, D. A.; Abbot, D. S.; Weare, J.

    2014-12-01

    Tropical cyclones (TCs) present a challenge to modeling using general circulation models (GCMs) because they involve processes and structures that are too fine for GCMs to resolve. TCs have fine structures - e.g. the eye, eyewall, and rain bands - with length scales on the order of 10 km, while GCMs have typical resolutions on the order of 50-100 km. High resolution GCM runs that are sufficiently long to exhibit multiple TCs can be prohibitively computationally expensive. Thus, while GCMs exhibit TC-like vortices with similar spatial and temporal frequencies to observed TCs, the ability of GCMs to reproduce fine TC structures remains largely untested. In this study, we use recently developed rare event analysis and simulation methods to selectively simulate TCs under GCMs at very high resolution. These rare event simulation methods have been developed mostly in the context of computational chemistry, but are broadly applicable. They allow (either by careful manipulation of the model or by selection of trajectories) direct and detailed interrogation of the event of interest without introducing error and without the need to simulated for long periods of time to see the event. By creating targeted, high resolution GCM simulations with many TCs, we hope to determine whether or not GCMs can capture fine TC structures such as eyewalls and individual rain bands.

  5. Achieving High Resolution Timer Events in Virtualized Environment

    PubMed Central

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs—Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service). Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events. PMID:26177366

  6. Regression analysis of mixed recurrent-event and panel-count data with additive rate models.

    PubMed

    Zhu, Liang; Zhao, Hui; Sun, Jianguo; Leisenring, Wendy; Robison, Leslie L

    2015-03-01

    Event-history studies of recurrent events are often conducted in fields such as demography, epidemiology, medicine, and social sciences (Cook and Lawless, 2007, The Statistical Analysis of Recurrent Events. New York: Springer-Verlag; Zhao et al., 2011, Test 20, 1-42). For such analysis, two types of data have been extensively investigated: recurrent-event data and panel-count data. However, in practice, one may face a third type of data, mixed recurrent-event and panel-count data or mixed event-history data. Such data occur if some study subjects are monitored or observed continuously and thus provide recurrent-event data, while the others are observed only at discrete times and hence give only panel-count data. A more general situation is that each subject is observed continuously over certain time periods but only at discrete times over other time periods. There exists little literature on the analysis of such mixed data except that published by Zhu et al. (2013, Statistics in Medicine 32, 1954-1963). In this article, we consider the regression analysis of mixed data using the additive rate model and develop some estimating equation-based approaches to estimate the regression parameters of interest. Both finite sample and asymptotic properties of the resulting estimators are established, and the numerical studies suggest that the proposed methodology works well for practical situations. The approach is applied to a Childhood Cancer Survivor Study that motivated this study.

  7. Investigating rare events with nonequilibrium work measurements. II. Transition and reaction rates.

    PubMed

    Moradi, Mahmoud; Sagui, Celeste; Roland, Christopher

    2014-01-21

    We present a formalism for investigating transition pathways and transition probabilities for rare events in biomolecular systems. The formalism is based on combining Transition Path Theory with the results of nonequilibrium work relations, and shows that the equilibrium and nonequilibrium transition rates are in fact related. Aside from its fundamental importance, this allows for the calculation of relative equilibrium reaction rates with driven nonequilibrium simulations such as Steered Molecular Dynamics. The workings of the formalism are illustrated with a few typical numerical examples.

  8. High Resolution Measurement of the Glycolytic Rate

    PubMed Central

    Bittner, Carla X.; Loaiza, Anitsi; Ruminot, Iván; Larenas, Valeria; Sotelo-Hitschfeld, Tamara; Gutiérrez, Robin; Córdova, Alex; Valdebenito, Rocío; Frommer, Wolf B.; Barros, L. Felipe

    2010-01-01

    The glycolytic rate is sensitive to physiological activity, hormones, stress, aging, and malignant transformation. Standard techniques to measure the glycolytic rate are based on radioactive isotopes, are not able to resolve single cells and have poor temporal resolution, limitations that hamper the study of energy metabolism in the brain and other organs. A new method is described in this article, which makes use of a recently developed FRET glucose nanosensor to measure the rate of glycolysis in single cells with high temporal resolution. Used in cultured astrocytes, the method showed for the first time that glycolysis can be activated within seconds by a combination of glutamate and K+, supporting a role for astrocytes in neurometabolic and neurovascular coupling in the brain. It was also possible to make a direct comparison of metabolism in neurons and astrocytes lying in close proximity, paving the way to a high-resolution characterization of brain energy metabolism. Single-cell glycolytic rates were also measured in fibroblasts, adipocytes, myoblasts, and tumor cells, showing higher rates for undifferentiated cells and significant metabolic heterogeneity within cell types. This method should facilitate the investigation of tissue metabolism at the single-cell level and is readily adaptable for high-throughput analysis. PMID:20890447

  9. High rate, high reliability Li/SO2 cells

    NASA Astrophysics Data System (ADS)

    Chireau, R.

    1982-03-01

    The use of the lithium/sulfur dioxide system for aerospace applications is discussed. The high rate density in the system is compared to some primary systems: mercury zinc, silver zinc, and magnesium oxide. Estimates are provided of the storage life and shelf life of typical lithium sulfur batteries. The design of lithium cells is presented and criteria are given for improving the output of cells in order to achieve high rate and high reliability.

  10. Measurement Differences from Rating Posttraumatic Stress Disorder Symptoms in Response to Differentially Distressing Traumatic Events

    ERIC Educational Resources Information Center

    Elhai, Jon D.; Fine, Thomas H.

    2012-01-01

    The authors explored differences in posttraumatic stress disorder (PTSD) symptoms as a result of rating symptoms from two separate, differentially distressing traumatic events. In an initial sample of 400 nonclinical participants, the authors inquired through a web survey about previous psychological trauma, instructing participants to nominate…

  11. Measurement Differences from Rating Posttraumatic Stress Disorder Symptoms in Response to Differentially Distressing Traumatic Events

    ERIC Educational Resources Information Center

    Elhai, Jon D.; Fine, Thomas H.

    2012-01-01

    The authors explored differences in posttraumatic stress disorder (PTSD) symptoms as a result of rating symptoms from two separate, differentially distressing traumatic events. In an initial sample of 400 nonclinical participants, the authors inquired through a web survey about previous psychological trauma, instructing participants to nominate…

  12. High Rate for Type IC Supernovae

    SciTech Connect

    Muller, R.A.; Marvin-Newberg, H.J.; Pennypacker, Carl R.; Perlmutter, S.; Sasseen, T.P.; Smith, C.K.

    1991-09-01

    Using an automated telescope we have detected 20 supernovae in carefully documented observations of nearby galaxies. The supernova rates for late spiral (Sbc, Sc, Scd, and Sd) galaxies, normalized to a blue luminosity of 10{sup 10} L{sub Bsun}, are 0.4 h{sup 2}, 1.6 h{sup 2}, and 1.1 h{sup 2} per 100 years for SNe type la, Ic, and II. The rate for type Ic supernovae is significantly higher than found in previous surveys. The rates are not corrected for detection inefficiencies, and do not take into account the indications that the Ic supernovae are fainter on the average than the previous estimates; therefore the true rates are probably higher. The rates are not strongly dependent on the galaxy inclination, in contradiction to previous compilations. If the Milky Way is a late spiral, then the rate of Galactic supernovae is greater than 1 per 30 {+-} 7 years, assuming h = 0.75. This high rate has encouraging consequences for future neutrino and gravitational wave observatories.

  13. [Hopes of high dose-rate radiotherapy].

    PubMed

    Fouillade, Charles; Favaudon, Vincent; Vozenin, Marie-Catherine; Romeo, Paul-Henri; Bourhis, Jean; Verrelle, Pierre; Devauchelle, Patrick; Patriarca, Annalisa; Heinrich, Sophie; Mazal, Alejandro; Dutreix, Marie

    2017-04-01

    In this review, we present the synthesis of the newly acquired knowledge concerning high dose-rate irradiations and the hopes that these new radiotherapy modalities give rise to. The results were presented at a recent symposium on the subject. Copyright © 2017. Published by Elsevier Masson SAS.

  14. Baltimore District Tackles High Suspension Rates

    ERIC Educational Resources Information Center

    Maxwell, Lesli A.

    2007-01-01

    This article reports on how the Baltimore District tackles its high suspension rates. Driven by an increasing belief that zero-tolerance disciplinary policies are ineffective, more educators are embracing strategies that do not exclude misbehaving students from school for offenses such as insubordination, disrespect, cutting class, tardiness, and…

  15. Baltimore District Tackles High Suspension Rates

    ERIC Educational Resources Information Center

    Maxwell, Lesli A.

    2007-01-01

    This article reports on how the Baltimore District tackles its high suspension rates. Driven by an increasing belief that zero-tolerance disciplinary policies are ineffective, more educators are embracing strategies that do not exclude misbehaving students from school for offenses such as insubordination, disrespect, cutting class, tardiness, and…

  16. Understanding High School Graduation Rates in Georgia

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  17. Understanding High School Graduation Rates in Oklahoma

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  18. Understanding High School Graduation Rates in Kentucky

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  19. Understanding High School Graduation Rates in Nevada

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  20. Understanding High School Graduation Rates in Kansas

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  1. Understanding High School Graduation Rates in Connecticut

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  2. Understanding High School Graduation Rates in Indiana

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  3. Understanding High School Graduation Rates in Alaska

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  4. Understanding High School Graduation Rates in Hawaii

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  5. Understanding High School Graduation Rates in Wisconsin

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  6. Understanding High School Graduation Rates in Utah

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  7. Understanding High School Graduation Rates in Alabama

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  8. Understanding High School Graduation Rates in Maryland

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  9. Understanding High School Graduation Rates in Tennessee

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  10. Understanding High School Graduation Rates in Nebraska

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  11. Understanding High School Graduation Rates in Missouri

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  12. Understanding High School Graduation Rates in Arizona

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  13. Understanding High School Graduation Rates in Montana

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  14. Understanding High School Graduation Rates in Iowa

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  15. Understanding High School Graduation Rates in Vermont

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  16. Understanding High School Graduation Rates in California

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  17. Understanding High School Graduation Rates in Mississippi

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  18. Understanding High School Graduation Rates in Ohio

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  19. Understanding High School Graduation Rates in Illinois

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  20. Understanding High School Graduation Rates in Louisiana

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  1. Understanding High School Graduation Rates in Virginia

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  2. Understanding High School Graduation Rates in Florida

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  3. Understanding High School Graduation Rates in Delaware

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  4. Understanding High School Graduation Rates in Idaho

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  5. Understanding High School Graduation Rates in Maine

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  6. Understanding High School Graduation Rates in Massachusetts

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  7. Understanding High School Graduation Rates in Michigan

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  8. Understanding High School Graduation Rates in Pennsylvania

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  9. Understanding High School Graduation Rates in Oregon

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  10. Understanding High School Graduation Rates in Washington

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  11. Understanding High School Graduation Rates in Minnesota

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  12. Understanding High School Graduation Rates in Wyoming

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  13. Understanding High School Graduation Rates in Texas

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  14. Understanding High School Graduation Rates in Arkansas

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  15. Understanding High School Graduation Rates in Colorado

    ERIC Educational Resources Information Center

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  16. High rate constitutive modeling of aluminium alloy tube

    NASA Astrophysics Data System (ADS)

    Salisbury, C. P.; Worswick, M. J.; Mayer, R.

    2006-08-01

    As the need for fuel efficient automobiles increases, car designers are investigating light-weight materials for automotive bodies that will reduce the overall automobile weight. Aluminium alloy tube is a desirable material to use in automotive bodies due to its light weight. However, aluminium suffers from lower formability than steel and its energy absorption ability in a crash event after a forming operation is largely unknown. As part of a larger study on the relationship between crashworthiness and forming processes, constitutive models for 3mm AA5754 aluminium tube were developed. A nominal strain rate of 100/s is often used to characterize overall automobile crash events, whereas strain rates on the order of 1000/s can occur locally. Therefore, tests were performed at quasi-static rates using an Instron test fixture and at strain rates of 500/s to 1500/s using a tensile split Hopkinson bar. High rate testing was then conducted at rates of 500/s, 1000/s and 1500/s at 21circC, 150circC and 300circC. The generated data was then used to determine the constitutive parameters for the Johnson-Cook and Zerilli-Armstrong material models.

  17. A miniature high repetition rate shock tube.

    PubMed

    Tranter, R S; Lynch, P T

    2013-09-01

    A miniature high repetition rate shock tube with excellent reproducibility has been constructed to facilitate high temperature, high pressure, gas phase experiments at facilities such as synchrotron light sources where space is limited and many experiments need to be averaged to obtain adequate signal levels. The shock tube is designed to generate reaction conditions of T > 600 K, P < 100 bars at a cycle rate of up to 4 Hz. The design of the apparatus is discussed in detail, and data are presented to demonstrate that well-formed shock waves with predictable characteristics are created, repeatably. Two synchrotron-based experiments using this apparatus are also briefly described here, demonstrating the potential of the shock tube for research at synchrotron light sources.

  18. High resolution simulations of extreme weather event in south Sardinia

    NASA Astrophysics Data System (ADS)

    Dessy, C.

    2010-05-01

    In the last decade, like most region of Mediterranean Europe, Sardinia has experienced severe precipitation events generating flash floods resulting in loss of lives and large economic damage. A numerical meteorological operational set-up is applied in the local weather service with the aim to improve the operational short range weather forecast of the Service with particular attention to intense, mostly rare and potentially severe, events. On the early hours of 22 October 2008 an intense and almost stationary mesoscale convective system interested particularly the south of Sardinia, heavy precipitation caused a flash flood with fatalities and numerous property damages. The event was particularly intense: about 400 mm of rain in 12 hours (a peak of 150 mm in an hour) were misured by the regional network of weather stations and these values appear extremely meaningfulls since those are about seven times the climatological monthly rainfall for that area and nearly the climatological annual rainfall. With the aim to improve significantly quantitative precipitation forecasting, it was evaluated a different set-up of a high resolution convection resolving model (MM5) initialised with different initial and boundary conditions (ECMWF and NCAR). In this paper it is discussed the meteorological system related to the mentioned event by using different numerical weather models (GCM and LAM) combined with conventional data, radar Doppler and Meteosat images. Preliminary results say that a different set-up of a non hydrostatic model can forecast severe convection events in advance of about one day and produce more realistic rainfall than that current operational and also improve the weather forecasts to respect the ECMWF-GCM. So it could drive an operational alert system in order to limit the risks associated with heavy precipitation events.

  19. Adaptable, high recall, event extraction system with minimal configuration

    PubMed Central

    2015-01-01

    Background Biomedical event extraction has been a major focus of biomedical natural language processing (BioNLP) research since the first BioNLP shared task was held in 2009. Accordingly, a large number of event extraction systems have been developed. Most such systems, however, have been developed for specific tasks and/or incorporated task specific settings, making their application to new corpora and tasks problematic without modification of the systems themselves. There is thus a need for event extraction systems that can achieve high levels of accuracy when applied to corpora in new domains, without the need for exhaustive tuning or modification, whilst retaining competitive levels of performance. Results We have enhanced our state-of-the-art event extraction system, EventMine, to alleviate the need for task-specific tuning. Task-specific details are specified in a configuration file, while extensive task-specific parameter tuning is avoided through the integration of a weighting method, a covariate shift method, and their combination. The task-specific configuration and weighting method have been employed within the context of two different sub-tasks of BioNLP shared task 2013, i.e. Cancer Genetics (CG) and Pathway Curation (PC), removing the need to modify the system specifically for each task. With minimal task specific configuration and tuning, EventMine achieved the 1st place in the PC task, and 2nd in the CG, achieving the highest recall for both tasks. The system has been further enhanced following the shared task by incorporating the covariate shift method and entity generalisations based on the task definitions, leading to further performance improvements. Conclusions We have shown that it is possible to apply a state-of-the-art event extraction system to new tasks with high levels of performance, without having to modify the system internally. Both covariate shift and weighting methods are useful in facilitating the production of high recall systems

  20. The Effects of Significant International Sports Events on Hungarian Suicide Rates.

    PubMed

    Bozsonyi, Karoly; Osvath, Peter; Fekete, Sandor; Bálint, Lajos

    2016-03-01

    Several studies found a significant relationship between important sport events and suicidal behavior. We set out to investigate whether there is a significant relationship between the raw suicide rate and the most important international sports events (Olympic Games, FIFA World Cup, UEFA European Championship) in such an achievement-oriented society as the Hungarian one, where these sport events receive great attention. We examined suicide cases occurring over 15,706 days between January 1, 1970, and December 31, 2012 (43 years), separately for each gender. Because of the age-specific characteristics of suicide, the effects of these sport events were analyzed for the middle-aged (30-59 years old) and the elderly (over 60 years old) generations as well as for gender-specific population groups. The role of international sport events was examined with the help of time-series intervention analysis after cyclical and seasonal components were removed. Intervention analysis was based on the ARIMA model. Our results showed that only the Olympic Games had a significant effect in the middle-aged population. Neither in the older male nor in any of the female age groups was a relationship between suicide and Olympic Games detected. The Olympic Games seem to decrease the rate of suicide among middle-aged men, slightly but significantly.

  1. High strain rate behaviour of polypropylene microfoams

    NASA Astrophysics Data System (ADS)

    Gómez-del Río, T.; Garrido, M. A.; Rodríguez, J.; Arencón, D.; Martínez, A. B.

    2012-08-01

    Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc.) or personal safety (helmets, knee-pads, etc.). In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry) is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s-1) in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB). Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  2. Mental workload measurement: Event-related potentials and ratings of workload and fatigue

    NASA Technical Reports Server (NTRS)

    Biferno, M. A.

    1985-01-01

    Event-related potentials were elicited when a digitized word representing a pilot's call-sign was presented. This auditory probe was presented during 27 workload conditions in a 3x3x3 design where the following variables were manipulated: short-term load, tracking task difficulty, and time-on-task. Ratings of workload and fatigue were obtained between each trial of a 2.5-hour test. The data of each subject were analyzed individually to determine whether significant correlations existed between subjective ratings and ERP component measures. Results indicated that a significant number of subjects had positive correlations between: (1) ratings of workload and P300 amplitude, (2) ratings of workload and N400 amplitude, and (3) ratings of fatigue and P300 amplitude. These data are the first to show correlations between ratings of workload or fatigue and ERP components thereby reinforcing their validity as measures of mental workload and fatigue.

  3. Highly stable high-rate discriminator for nuclear counting

    NASA Technical Reports Server (NTRS)

    English, J. J.; Howard, R. H.; Rudnick, S. J.

    1969-01-01

    Pulse amplitude discriminator is specially designed for nuclear counting applications. At very high rates, the threshold is stable. The output-pulse width and the dead time change negligibly. The unit incorporates a provision for automatic dead-time correction.

  4. High-Rate Capable Floating Strip Micromegas

    NASA Astrophysics Data System (ADS)

    Bortfeldt, Jonathan; Bender, Michael; Biebel, Otmar; Danger, Helge; Flierl, Bernhard; Hertenberger, Ralf; Lösel, Philipp; Moll, Samuel; Parodi, Katia; Rinaldi, Ilaria; Ruschke, Alexander; Zibell, André

    2016-04-01

    We report on the optimization of discharge insensitive floating strip Micromegas (MICRO-MEsh GASeous) detectors, fit for use in high-energy muon spectrometers. The suitability of these detectors for particle tracking is shown in high-background environments and at very high particle fluxes up to 60 MHz/cm2. Measurement and simulation of the microscopic discharge behavior have demonstrated the excellent discharge tolerance. A floating strip Micromegas with an active area of 48 cm × 50 cm with 1920 copper anode strips exhibits in 120 GeV pion beams a spatial resolution of 50 μm at detection efficiencies above 95%. Pulse height, spatial resolution and detection efficiency are homogeneous over the detector. Reconstruction of particle track inclination in a single detector plane is discussed, optimum angular resolutions below 5° are observed. Systematic deviations of this μTPC-method are fully understood. The reconstruction capabilities for minimum ionizing muons are investigated in a 6.4 cm × 6.4 cm floating strip Micromegas under intense background irradiation of the whole active area with 20 MeV protons at a rate of 550 kHz. The spatial resolution for muons is not distorted by space charge effects. A 6.4 cm × 6.4 cm floating strip Micromegas doublet with low material budget is investigated in highly ionizing proton and carbon ion beams at particle rates between 2 MHz and 2 GHz. Stable operation up to the highest rates is observed, spatial resolution, detection efficiencies, the multi-hit and high-rate capability are discussed.

  5. Phosphor thermometry at high repetition rates

    NASA Astrophysics Data System (ADS)

    Fuhrmann, N.; Brübach, J.; Dreizler, A.

    2013-09-01

    Phosphor thermometry is a semi-invasive surface temperature measurement technique utilizing the luminescence properties of thermographic phosphors. Typically these ceramic materials are coated onto the object of interest and are excited by a short UV laser pulse. Photomultipliers and high-speed camera systems are used to transiently detect the subsequently emitted luminescence decay point wise or two-dimensionally resolved. Based on appropriate calibration measurements, the luminescence lifetime is converted to temperature. Up to now, primarily Q-switched laser systems with repetition rates of 10 Hz were employed for excitation. Accordingly, this diagnostic tool was not applicable to resolve correlated temperature transients at time scales shorter than 100 ms. For the first time, the authors realized a high-speed phosphor thermometry system combining a highly repetitive laser in the kHz regime and a fast decaying phosphor. A suitable material was characterized regarding its temperature lifetime characteristic and precision. Additionally, the influence of laser power on the phosphor coating in terms of heating effects has been investigated. A demonstration of this high-speed technique has been conducted inside the thermally highly transient system of an optically accessible internal combustion engine. Temperatures have been measured with a repetition rate of one sample per crank angle degree at an engine speed of 1000 rpm. This experiment has proven that high-speed phosphor thermometry is a promising diagnostic tool for the resolution of surface temperature transients.

  6. Comparison of military and civilian reporting rates for smallpox vaccine adverse events.

    PubMed

    McMahon, A W; Zinderman, C; Ball, R; Gupta, G; Braun, M M

    2007-06-01

    US smallpox vaccination (SMA) started most recently in December 2002. Military and civilian personnel report adverse events (AEs) to the Vaccine Adverse Event Reporting System (VAERS), a surveillance system that relies on spontaneous reports. Although reported rates of probable myo/pericarditis after SMA in the literature are similar between military personnel and civilian healthcare workers, some civilian AE reporting rates after SMA appeared higher than those in the military. Determine if SMA-associated reporting rates are different in civilians than in the military, considering age, sex, seriousness, and expectedness of the AE, as well as self-reporting. Numerators were SMA reports in VAERS from 12/12/02 to 3/1/04. Limitations of VAERS include underreporting and lack of diagnostic confirmation. Denominators were number of military and civilian vaccinees. Reporting rates stratified by age and sex of serious and non-serious AEs were significantly higher in civilian than military personnel ages <55 years (rate ratios 4-27). These rate ratios decreased with increasing age. Reporting rates in VAERS differed significantly and substantially in civilians compared to military personnel <55 years of age. Differences in stimulated passive surveillance systems, and AE reporting practices, including the 'threshold' for reporting most likely explain these findings. These results suggest that in the case of smallpox vaccine AEs, there may be systematic differences in reporting completeness between the civilian and military sectors, and that passive surveillance data should be interpreted with caution. Copyright (c) 2006 John Wiley & Sons, Ltd.

  7. High strain rate characterization of polymers

    NASA Astrophysics Data System (ADS)

    Siviour, Clive R.

    2017-01-01

    This paper reviews the literature on the response of polymers to high strain rate deformation. The main focus is on the experimental techniques used to characterize this response. The paper includes a small number of examples as well as references to experimental data over a wide range of rates, which illustrate the key features of rate dependence in these materials; however this is by no means an exhaustive list. The aim of the paper is to give the reader unfamiliar with the subject an overview of the techniques available with sufficient references from which further information can be obtained. In addition to the `well established' techniques of the Hopkinson bar, Taylor Impact and Transverse impact, a discussion of the use of time-temperature superposition in interpreting and experimentally replicating high rate response is given, as is a description of new techniques in which mechanical parameters are derived by directly measuring wave propagation in specimens; these are particularly appropriate for polymers with low wave speeds. The vast topic of constitutive modelling is deliberately excluded from this review.

  8. High temperature electrochemical corrosion rate probes

    SciTech Connect

    Bullard, Sophie J.; Covino, Bernard S., Jr.; Holcomb, Gordon R.; Ziomek-Moroz, M.

    2005-09-01

    Corrosion occurs in the high temperature sections of energy production plants due to a number of factors: ash deposition, coal composition, thermal gradients, and low NOx conditions, among others. Electrochemical corrosion rate (ECR) probes have been shown to operate in high temperature gaseous environments that are similar to those found in fossil fuel combustors. ECR probes are rarely used in energy production plants at the present time, but if they were more fully understood, corrosion could become a process variable at the control of plant operators. Research is being conducted to understand the nature of these probes. Factors being considered are values selected for the Stern-Geary constant, the effect of internal corrosion, and the presence of conductive corrosion scales and ash deposits. The nature of ECR probes will be explored in a number of different atmospheres and with different electrolytes (ash and corrosion product). Corrosion rates measured using an electrochemical multi-technique capabilities instrument will be compared to those measured using the linear polarization resistance (LPR) technique. In future experiments, electrochemical corrosion rates will be compared to penetration corrosion rates determined using optical profilometry measurements.

  9. Do co-intoxicants increase adverse event rates in the first 24 hours in patients resuscitated from acute opioid overdose?

    PubMed

    Mirakbari, Seyed Mostafa; Innes, Grant D; Christenson, Jim; Tilley, Jessica; Wong, Hubert

    2003-01-01

    Patients frequently arrive in emergency departments (EDs) after being resuscitated from opioid overdose. Autopsy studies suggest that multidrug intoxication is a major risk factor for adverse outcomes after acute heroin overdose in patients. If this is true, there may be high-risk drug combinations that identify patients who require more intensive monitoring and prolonged observation. Our objective was to determine the impact of co-intoxication with alcohol, cocaine, or CNS depressant drugs on short-term adverse event rates in patients resuscitated from acute opioid overdose. Data were extracted from the database of a prospective opioid overdose cohort study conducted between May 1997 and 1999. Patients were prospectively enrolled if they received naloxone for presumed opioid overdose. Investigators gathered clinical, demographic, and other predictor variables, including co-intoxicants used. Patients were followed to identify prespecified adverse outcome events occurring within 24 h, and multiple logistic regression was used to determine the association of concomitant drug use on short-term adverse event rates. Of 1155 patients studied, 58 (5%) had pure opioid overdose and 922 (80%) reported co-intoxicants, including alcohol, cocaine, and CNS depressants. Overall, out of 1056 patients with known outcome status there were 123 major adverse events (11.6%) and 194 minor adverse events (18.4%). After adjustment for age, gender, HIV status, cardiovascular disease, pulmonary disease and diabetes, we found that coadministration of alcohol, cocaine, or CNS depressants, alone or in combination, was not associated with increased risk of death or adverse events during the 24 h follow-up period. In patients resuscitated from acute opioid overdose, short-term outcomes are similar for patients with pure opioid overdose and multidrug intoxications. A history of cointoxication cannot be used to identify high-risk patients who require more intensive ED monitoring or prolonged

  10. Analytical Modeling of High Rate Processes.

    DTIC Science & Technology

    2007-11-02

    TYPE AND DATES COVERED 1 13 Apr 98 Final (01 Sep 94 - 31 Aug 97) 4. TITLE AND SUBTITLE 5 . FUNDING NUMBERS Analytical Modeling of High Rate Processes...20332- 8050 FROM: S. E. Jones, University Research Professor Department of Aerospace Engineering and Mechanics University of Alabama SUBJECT: Final...Mr. Sandor Augustus and Mr. Jeffrey A. Drinkard. There are no outstanding commitments. The balance in the account, as of July 31 , 1997, was $102,916.42

  11. HIGH ENERGY RATE EXTRUSION OF URANIUM

    DOEpatents

    Lewis, L.

    1963-07-23

    A method of extruding uranium at a high energy rate is described. Conditions during the extrusion are such that the temperature of the metal during extrusion reaches a point above the normal alpha to beta transition, but the metal nevertheless remains in the alpha phase in accordance with the Clausius- Clapeyron equation. Upon exiting from the die, the metal automatically enters the beta phase, after which the metal is permitted to cool. (AEC)

  12. Reserve, flowing electrolyte, high rate lithium battery

    NASA Astrophysics Data System (ADS)

    Puskar, M.; Harris, P.

    Flowing electrolyte Li/SOCl2 tests in single cell and multicell bipolar fixtures have been conducted, and measurements are presented for electrolyte flow rates, inlet and outlet temperatures, fixture temperatures at several points, and the pressure drop across the fixture. Reserve lithium batteries with flowing thionyl-chloride electrolytes are found to be capable of very high energy densities with usable voltages and capacities at current densities as high as 500 mA/sq cm. At this current density, a battery stack 10 inches in diameter is shown to produce over 60 kW of power while maintaining a safe operating temperature.

  13. Misinformation can influence memory for recently experienced, highly stressful events.

    PubMed

    Morgan, C A; Southwick, Steven; Steffian, George; Hazlett, Gary A; Loftus, Elizabeth F

    2013-01-01

    A large body of research has demonstrated that exposure to misinformation can lead to distortions in human memory for genuinely experienced objects or people. The current study examined whether misinformation could affect memory for a recently experienced, personally relevant, highly stressful event. In the present study we assessed the impact of misinformation on memory in over 800 military personnel confined in the stressful, mock POW camp phase of Survival School training. Misinformation introduced after the negatively affected memory for the details of the event (such as the presence of glasses or weapons), and also affected the accuracy of identification of an aggressive interrogator. In some conditions more than half of the subjects exposed to a misleading photograph falsely identified a different individual as their interrogator after the interrogation was over. These findings demonstrate that memories for stressful events are highly vulnerable to modification by exposure to misinformation, even in individuals whose level of training and experience might be thought to render them relatively immune to such influences. Published by Elsevier Ltd.

  14. SLHC, the High-Luminosity Upgrade (public event)

    ScienceCinema

    None

    2016-07-12

    In the morning of June 23rd a public event is organised in CERN's Council Chamber with the aim of providing the particle physics community with up-to-date information about the strategy for the LHC luminosity upgrade and to describe the current status of preparation work. The presentations will provide an overview of the various accelerator sub-projects, the LHC physics prospects and the upgrade plans of ATLAS and CMS. This event is organised in the framework of the SLHC-PP project, which receives funding from the European Commission for the preparatory phase of the LHC High Luminosity Upgrade project. Informing the public is among the objectives of this EU-funded project. A simultaneous transmission of this meeting will be broadcast, available at the following address: http://webcast.cern.ch/

  15. High rate pulse processing algorithms for microcalorimeters

    SciTech Connect

    Rabin, Michael; Hoover, Andrew S; Bacrania, Mnesh K; Tan, Hui; Breus, Dimitry; Henning, Wolfgang; Sabourov, Konstantin; Collins, Jeff; Warburton, William K; Dorise, Bertrand; Ullom, Joel N

    2009-01-01

    It has been demonstrated that microcalorimeter spectrometers based on superconducting transition-edge-sensor can readily achieve sub-100 eV energy resolution near 100 keV. However, the active volume of a single microcalorimeter has to be small to maintain good energy resolution, and pulse decay times are normally in the order of milliseconds due to slow thermal relaxation. Consequently, spectrometers are typically built with an array of microcalorimeters to increase detection efficiency and count rate. Large arrays, however, require as much pulse processing as possible to be performed at the front end of the readout electronics to avoid transferring large amounts of waveform data to a host computer for processing. In this paper, they present digital filtering algorithms for processing microcalorimeter pulses in real time at high count rates. The goal for these algorithms, which are being implemented in the readout electronics that they are also currently developing, is to achieve sufficiently good energy resolution for most applications while being (a) simple enough to be implemented in the readout electronics and (b) capable of processing overlapping pulses and thus achieving much higher output count rates than the rates that existing algorithms are currently achieving. Details of these algorithms are presented, and their performance was compared to that of the 'optimal filter' that is the dominant pulse processing algorithm in the cryogenic-detector community.

  16. High Strain Rate Behavior of Polyurea Compositions

    NASA Astrophysics Data System (ADS)

    Joshi, Vasant; Milby, Christopher

    2011-06-01

    Polyurea has been gaining importance in recent years due to its impact resistance properties. The actual compositions of this viscoelastic material must be tailored for specific use. It is therefore imperative to study the effect of variations in composition on the properties of the material. High-strain-rate response of three polyurea compositions with varying molecular weights has been investigated using a Split Hopkinson Pressure Bar arrangement equipped with titanium bars. The polyurea compositions were synthesized from polyamines (Versalink, Air Products) with a multi-functional isocyanate (Isonate 143L, Dow Chemical). Amines with molecular weights of 1000, 650, and a blend of 250/1000 have been used in the current investigation. The materials have been tested up to strain rates of 6000/s. Results from these tests have shown interesting trends on the high rate behavior. While higher molecular weight composition show lower yield, they do not show dominant hardening behavior. On the other hand, the blend of 250/1000 show higher load bearing capability but lower strain hardening effects than the 600 and 1000 molecular weight amine based materials. Refinement in experimental methods and comparison of results using aluminum Split Hopkinson Bar is presented.

  17. High strain rate behavior of polyurea compositions

    NASA Astrophysics Data System (ADS)

    Joshi, Vasant S.; Milby, Christopher

    2012-03-01

    High-strain-rate response of three polyurea compositions with varying molecular weights has been investigated using a Split Hopkinson Pressure Bar arrangement equipped with aluminum bars. Three polyurea compositions were synthesized from polyamines (Versalink, Air Products) with a multi-functional isocyanate (Isonate 143L, Dow Chemical). Amines with molecular weights of 1000, 650, and a blend of 250/1000 have been used in the current investigation. These materials have been tested to strain rates of over 6000/s. High strain rate results from these tests have shown varying trends as a function of increasing strain. While higher molecular weight composition show lower yield, they do not show dominant hardening behavior at lower strain. On the other hand, the blend of 250/1000 show higher load bearing capability but lower strain hardening effects than the 600 and 1000 molecular weight amine based materials. Results indicate that the initial increase in the modulus of the blend of 250/1000 may lead to the loss of strain hardening characteristics as the material is compressed to 50% strain, compared to 1000 molecular weight amine based material.

  18. High Strain Rate Behavior of Nanoporous Tantalum

    NASA Astrophysics Data System (ADS)

    Ruestes, Carlos J.; Bringa, Eduardo M.; Stukowski, Alexander; Rodriguez Nieva, Joaquin F.; Bertolino, Graciela; Tang, Yizhe; Meyers, Marc A.

    2012-02-01

    Nano-scale failure under extreme conditions is not well understood. In addition to porosity arising from mechanical failure at high strain rates, porous structures also develop due to radiation damage. Therefore, understanding the role of porosity on mechanical behavior is important for the assessment and development of materials like metallic foams, and materials for new fission and fusion reactors, with improved mechanical properties. We carry out molecular dynamics (MD) simulations of a Tantalum (a model body-centered cubic metal) crystal with a collection of nanovoids under compression. The effects of high strain rate, ranging from 10^7s-1 to 10^10s-1, on the stress strain curve and on dislocation activity are examined. We find massive total dislocation densities, and estimate a much lower density of mobile dislocations, due to the formation of junctions. Despite the large stress and strain rate, we do not observe twin formation, since nanopores are effective dislocation production sources. A significant fraction of dislocations survive unloading, unlike what happens in fcc metals, and future experiments might be able to study similar recovered samples and find clues to their plastic behavior during loading.

  19. High strain-rate magnetoelasticity in Galfenol

    NASA Astrophysics Data System (ADS)

    Domann, J. P.; Loeffler, C. M.; Martin, B. E.; Carman, G. P.

    2015-09-01

    This paper presents the experimental measurements of a highly magnetoelastic material (Galfenol) under impact loading. A Split-Hopkinson Pressure Bar was used to generate compressive stress up to 275 MPa at strain rates of either 20/s or 33/s while measuring the stress-strain response and change in magnetic flux density due to magnetoelastic coupling. The average Young's modulus (44.85 GPa) was invariant to strain rate, with instantaneous stiffness ranging from 25 to 55 GPa. A lumped parameters model simulated the measured pickup coil voltages in response to an applied stress pulse. Fitting the model to the experimental data provided the average piezomagnetic coefficient and relative permeability as functions of field strength. The model suggests magnetoelastic coupling is primarily insensitive to strain rates as high as 33/s. Additionally, the lumped parameters model was used to investigate magnetoelastic transducers as potential pulsed power sources. Results show that Galfenol can generate large quantities of instantaneous power (80 MW/m3 ), comparable to explosively driven ferromagnetic pulse generators (500 MW/m3 ). However, this process is much more efficient and can be cyclically carried out in the linear elastic range of the material, in stark contrast with explosively driven pulsed power generators.

  20. High strain rate deformation of layered nanocomposites.

    PubMed

    Lee, Jae-Hwang; Veysset, David; Singer, Jonathan P; Retsch, Markus; Saini, Gagan; Pezeril, Thomas; Nelson, Keith A; Thomas, Edwin L

    2012-01-01

    Insight into the mechanical behaviour of nanomaterials under the extreme condition of very high deformation rates and to very large strains is needed to provide improved understanding for the development of new protective materials. Applications include protection against bullets for body armour, micrometeorites for satellites, and high-speed particle impact for jet engine turbine blades. Here we use a microscopic ballistic test to report the responses of periodic glassy-rubbery layered block-copolymer nanostructures to impact from hypervelocity micron-sized silica spheres. Entire deformation fields are experimentally visualized at an exceptionally high resolution (below 10 nm) and we discover how the microstructure dissipates the impact energy via layer kinking, layer compression, extreme chain conformational flattening, domain fragmentation and segmental mixing to form a liquid phase. Orientation-dependent experiments show that the dissipation can be enhanced by 30% by proper orientation of the layers.

  1. High strain rate deformation of layered nanocomposites

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Hwang; Veysset, David; Singer, Jonathan P.; Retsch, Markus; Saini, Gagan; Pezeril, Thomas; Nelson, Keith A.; Thomas, Edwin L.

    2012-11-01

    Insight into the mechanical behaviour of nanomaterials under the extreme condition of very high deformation rates and to very large strains is needed to provide improved understanding for the development of new protective materials. Applications include protection against bullets for body armour, micrometeorites for satellites, and high-speed particle impact for jet engine turbine blades. Here we use a microscopic ballistic test to report the responses of periodic glassy-rubbery layered block-copolymer nanostructures to impact from hypervelocity micron-sized silica spheres. Entire deformation fields are experimentally visualized at an exceptionally high resolution (below 10 nm) and we discover how the microstructure dissipates the impact energy via layer kinking, layer compression, extreme chain conformational flattening, domain fragmentation and segmental mixing to form a liquid phase. Orientation-dependent experiments show that the dissipation can be enhanced by 30% by proper orientation of the layers.

  2. Civilian residential fire fatality rates: Six high-rate states versus six low-rate states

    NASA Astrophysics Data System (ADS)

    Hall, J. R., Jr.; Helzer, S. G.

    1983-08-01

    Results of an analysis of 1,600 fire fatalities occurring in six states with high fire-death rates and six states with low fire-death rates are presented. Reasons for the differences in rates are explored, with special attention to victim age, sex, race, and condition at time of ignition. Fire cause patterns are touched on only lightly but are addressed more extensively in the companion piece to this report, "Rural and Non-Rural Civilian Residential Fire Fatalities in Twelve States', NBSIR 82-2519.

  3. High frame-rate digital radiographic videography

    SciTech Connect

    King, N.S.P.; Cverna, F.H.; Albright, K.L.; Jaramillo, S.A.; Yates, G.J.; McDonald, T.E.; Flynn, M.J.; Tashman, S.

    1994-09-01

    High speed x-ray imaging can be an important tool for observing internal processes in a wide range of applications. In this paper we describe preliminary implementation of a system having the eventual goal of observing the internal dynamics of bone and joint reactions during loading. Two Los Alamos National Laboratory (LANL) gated and image intensified camera systems were used to record images from an x-ray image convertor tube to demonstrate the potential of high frame-rate digital radiographic videography in the analysis of bone and joint dynamics of the human body. Preliminary experiments were done at LANL to test the systems. Initial high frame-rate imaging (from 500 to 1000 frames/s) of a swinging pendulum mounted to the face of an X-ray image convertor tube demonstrated high contrast response and baseline sensitivity. The systems were then evaluated at the Motion Analysis Laboratory of Henry Ford Health Systems Bone and Joint Center. Imaging of a 9 inch acrylic disk with embedded lead markers rotating at approximately 1000 RPM, demonstrated the system response to a high velocity/high contrast target. By gating the P-20 phosphor image from the X-ray image convertor with a second image intensifier (II) and using a 100-microsecond wide optical gate through the second II, enough prompt light decay from the x-ray image convertor phosphor had taken place to achieve reduction of most of the motion blurring. Measurement of the marker velocity was made by using video frames acquired at 500 frames/s. The data obtained from both experiments successfully demonstrated the feasibility of the technique. Several key areas for improvement are discussed along with salient test results and experiment details.

  4. High-frame-rate digital radiographic videography

    NASA Astrophysics Data System (ADS)

    King, Nicholas S. P.; Cverna, Frank H.; Albright, Kevin L.; Jaramillo, Steven A.; Yates, George J.; McDonald, Thomas E.; Flynn, Michael J.; Tashman, Scott

    1994-10-01

    High speed x-ray imaging can be an important tool for observing internal processes in a wide range of applications. In this paper we describe preliminary implementation of a system having the eventual goal of observing the internal dynamics of bone and joint reactions during loading. Two Los Alamos National Laboratory (LANL) gated and image intensified camera systems were used to record images from an x-ray image convertor tube to demonstrate the potential of high frame-rate digital radiographic videography in the analysis of bone and joint dynamics of the human body. Preliminary experiments were done at LANL to test the systems. Initial high frame-rate imaging (from 500 to 1000 frames/s) of a swinging pendulum mounted to the face of an X-ray image convertor tube demonstrated high contrast response and baseline sensitivity. The systems were then evaluated at the Motion Analysis Laboratory of Henry Ford Health Systems Bone and Joint Center. Imaging of a 9 inch acrylic disk with embedded lead markers rotating at approximately 1000 RPM, demonstrated the system response to a high velocity/high contrast target. By gating the P-20 phosphor image from the X-ray image convertor with a second image intensifier (II) and using a 100 microsecond wide optical gate through the second II, enough prompt light decay from the x-ray image convertor phosphor had taken place to achieve reduction of most of the motion blurring. Measurement of the marker velocity was made by using video frames acquired at 500 frames/s. The data obtained from both experiments successfully demonstrated the feasibility of the technique. Several key areas for improvement are discussed along with salient test results and experiment details.

  5. Age-specific vibrissae growth rates: a tool for determining the timing of ecologically important events in Steller sea lions

    USGS Publications Warehouse

    Rea, L.D.; Christ, A.M.; Hayden, A.B.; Stegall, V.K.; Farley, S.D.; Stricker, Craig A.; Mellish, J.E.; Maniscalco, John M.; Waite, J.N.; Burkanov, V.N.; Pitcher, K.W.

    2015-01-01

    Steller sea lions (SSL; Eumetopias jubatus) grow their vibrissae continually, providing a multiyear record suitable for ecological and physiological studies based on stable isotopes. An accurate age-specific vibrissae growth rate is essential for registering a chronology along the length of the record, and for interpreting the timing of ecologically important events. We utilized four methods to estimate the growth rate of vibrissae in fetal, rookery pup, young-of-the-year (YOY), yearling, subadult, and adult SSL. The majority of vibrissae were collected from SSL live-captured in Alaska and Russia between 2000 and 2013 (n = 1,115), however, vibrissae were also collected from six adult SSL found dead on haul-outs and rookeries during field excursions to increase the sample size of this underrepresented age group. Growth rates of vibrissae were generally slower in adult (0.44 ± 0.15 cm/mo) and subadult (0.61 ± 0.10 cm/mo) SSL than in YOY (0.87 ± 0.28 cm/mo) and fetal (0.73 ± 0.05 cm/mo) animals, but there was high individual variability in these growth rates within each age group. Some variability in vibrissae growth rates was attributed to the somatic growth rate of YOY sea lions between capture events (P = 0.014, r2 = 0.206, n = 29).

  6. Fluctuations in Wikipedia access-rate and edit-event data

    NASA Astrophysics Data System (ADS)

    Kämpf, Mirko; Tismer, Sebastian; Kantelhardt, Jan W.; Muchnik, Lev

    2012-12-01

    Internet-based social networks often reflect extreme events in nature and society by drastic increases in user activity. We study and compare the dynamics of the two major complex processes necessary for information spread via the online encyclopedia ‘Wikipedia’, i.e., article editing (information upload) and article access (information viewing) based on article edit-event time series and (hourly) user access-rate time series for all articles. Daily and weekly activity patterns occur in addition to fluctuations and bursting activity. The bursts (i.e., significant increases in activity for an extended period of time) are characterized by a power-law distribution of durations of increases and decreases. For describing the recurrence and clustering of bursts we investigate the statistics of the return intervals between them. We find stretched exponential distributions of return intervals in access-rate time series, while edit-event time series yield simple exponential distributions. To characterize the fluctuation behavior we apply detrended fluctuation analysis (DFA), finding that most article access-rate time series are characterized by strong long-term correlations with fluctuation exponents α≈0.9. The results indicate significant differences in the dynamics of information upload and access and help in understanding the complex process of collecting, processing, validating, and distributing information in self-organized social networks.

  7. Addressing Angular Single-Event Effects in the Estimation of On-Orbit Error Rates

    DOE PAGES

    Lee, David S.; Swift, Gary M.; Wirthlin, Michael J.; ...

    2015-12-01

    Our study describes complications introduced by angular direct ionization events on space error rate predictions. In particular, prevalence of multiple-cell upsets and a breakdown in the application of effective linear energy transfer in modern-scale devices can skew error rates approximated from currently available estimation models. Moreover, this paper highlights the importance of angular testing and proposes a methodology to extend existing error estimation tools to properly consider angular strikes in modern-scale devices. Finally, these techniques are illustrated with test data provided from a modern 28 nm SRAM-based device.

  8. Reduced growth rate of Montastrea annularis following the 1987 1988 coral-bleaching event

    NASA Astrophysics Data System (ADS)

    Goreau, T. J.; Macfarlane, A. H.

    1990-04-01

    Montastrea annularis, the major Caribbean reef building coral, was severely affected by the unprecedented 1987 1988 bleaching event. Most colonies on the fore reef were affected but few were bleached in the back reef. Skeletal growth rates of M. annularis populations were measured non-destructively in the field at Discovery Bay, Jamaica, from the peak of bleaching in Nov. 1987 until recovery was almost complete, in May 1988. Unbleached corals grew at normal rates. Partially bleached corals survived but skeletal growth ceased through this period.

  9. Addressing Angular Single-Event Effects in the Estimation of On-Orbit Error Rates

    SciTech Connect

    Lee, David S.; Swift, Gary M.; Wirthlin, Michael J.; Draper, Jeffrey

    2015-12-01

    Our study describes complications introduced by angular direct ionization events on space error rate predictions. In particular, prevalence of multiple-cell upsets and a breakdown in the application of effective linear energy transfer in modern-scale devices can skew error rates approximated from currently available estimation models. Moreover, this paper highlights the importance of angular testing and proposes a methodology to extend existing error estimation tools to properly consider angular strikes in modern-scale devices. Finally, these techniques are illustrated with test data provided from a modern 28 nm SRAM-based device.

  10. Fuel droplet burning rates at high pressures.

    NASA Technical Reports Server (NTRS)

    Canada, G. S.; Faeth, G. M.

    1973-01-01

    Combustion of methanol, ethanol, propanol-1, n-pentane, n-heptane, and n-decane was observed in air under natural convection conditions, at pressures up to 100 atm. The droplets were simulated by porous spheres, with diameters in the range from 0.63 to 1.90 cm. The pressure levels of the tests were high enough so that near-critical combustion was observed for methanol and ethanol. Due to the high pressures, the phase-equilibrium models of the analysis included both the conventional low-pressure approach as well as high-pressure versions, allowing for real gas effects and the solubility of combustion-product gases in the liquid phase. The burning-rate predictions of the various theories were similar, and in fair agreement with the data. The high-pressure theory gave the best prediction for the liquid-surface temperatures of ethanol and propanol-1 at high pressure. The experiments indicated the approach of critical burning conditions for methanol and ethanol at pressures on the order of 80 to 100 atm, which was in good agreement with the predictions of both the low- and high-pressure analysis.

  11. Microalgal separation from high-rate ponds

    SciTech Connect

    Nurdogan, Y.

    1988-01-01

    High rate ponding (HRP) processes are playing an increasing role in the treatment of organic wastewaters in sunbelt communities. Photosynthetic oxygenation by algae has proved to cost only one-seventh as much as mechanical aeration for activated sludge systems. During this study, an advanced HRP, which produces an effluent equivalent to tertiary treatment has been studied. It emphasizes not only waste oxidation but also algal separation and nutrient removal. This new system is herein called advanced tertiary high rate ponding (ATHRP). Phosphorus removal in HRP systems is normally low because algal uptake of phosphorus is about one percent of their 200-300 mg/L dry weights. Precipitation of calcium phosphates by autofluocculation also occurs in HRP at high pH levels, but it is generally not complete due to insufficient calcium concentration in the pond. In the case of Richmond where the studies were conducted, the sewage is very low in calcium. Therefore, enhancement of natural autoflocculation was studied by adding small amounts of lime to the pond. Through this simple procedure phosphorus and nitrogen removals were virtually complete justifying the terminology ATHRP.

  12. Morphology of high-multiplicity events in heavy ion collisions

    NASA Astrophysics Data System (ADS)

    Naselsky, P.; Christensen, C. H.; Christensen, P. R.; Damgaard, P. H.; Frejsel, A.; Gaardhøje, J. J.; Hansen, A.; Hansen, M.; Kim, J.; Verkhodanov, O.; Wiedemann, U. A.

    2012-08-01

    We discuss opportunities that may arise from subjecting high-multiplicity events in relativistic heavy ion collisions to an analysis similar to the one used in cosmology for the study of fluctuations of the cosmic microwave background (CMB). To this end, we discuss examples of how pertinent features of heavy ion collisions including global characteristics, signatures of collective flow, and event-wise fluctuations are visually represented in a Mollweide projection commonly used in CMB analysis, and how they are statistically analyzed in an expansion over spherical harmonic functions. If applied to the characterization of purely azimuthal dependent phenomena such as collective flow, the expansion coefficients of spherical harmonics are seen to contain redundancies compared to the set of harmonic flow coefficients commonly used in heavy ion collisions. Our exploratory study indicates, however, that these redundancies may offer novel opportunities for a detailed characterization of those event-wise fluctuations that remain after subtraction of the dominant collective flow signatures. By construction, the proposed approach allows also for the characterization of more complex collective phenomena like higher-order flow and other sources of fluctuations, and it may be extended to the characterization of phenomena of noncollective origin such as jets.

  13. Accurate Event-Driven Motion Compensation in High-Resolution PET Incorporating Scattered and Random Events

    PubMed Central

    Dinelle, Katie; Cheng, Ju-Chieh; Shilov, Mikhail A.; Segars, William P.; Lidstone, Sarah C.; Blinder, Stephan; Rousset, Olivier G.; Vajihollahi, Hamid; Tsui, Benjamin M. W.; Wong, Dean F.; Sossi, Vesna

    2010-01-01

    With continuing improvements in spatial resolution of positron emission tomography (PET) scanners, small patient movements during PET imaging become a significant source of resolution degradation. This work develops and investigates a comprehensive formalism for accurate motion-compensated reconstruction which at the same time is very feasible in the context of high-resolution PET. In particular, this paper proposes an effective method to incorporate presence of scattered and random coincidences in the context of motion (which is similarly applicable to various other motion correction schemes). The overall reconstruction framework takes into consideration missing projection data which are not detected due to motion, and additionally, incorporates information from all detected events, including those which fall outside the field-of-view following motion correction. The proposed approach has been extensively validated using phantom experiments as well as realistic simulations of a new mathematical brain phantom developed in this work, and the results for a dynamic patient study are also presented. PMID:18672420

  14. Event Rate for LISA Gravitational Wave Signals from Black Hole-Massive Black Hole Coalescences

    NASA Technical Reports Server (NTRS)

    Bender, Peter L.

    2002-01-01

    Earlier work under a previous grant had been mainly on investigating the event rate for coalescences of white dwarfs or neutron stars with massive black holes (MBHs) in galactic nuclei. Under the new grant, two studies were undertaken. One was an approximate extension of the earlier study to stellar mass black holes as the lighter object, with masses in the range of roughly 3 to 20 solar mass rather than about 1 solar mass. The other was an improved estimate of the confusion noise due to galactic binaries against which the signals from BH-MBH coalescences would have to be detected. In the earlier work, the mass of the white dwarfs (WDs) and neutron stars (NSs) was assumed to be about the same as that of the evolved stars in the density cusp around the galactic center MBH. However, with the BH mass being substantially larger, the sinking down of pHs toward the center (mass segregation) became important, and was included in the model. A single representative mass of 7 solar mass was used. The other main difference involved what happened after the compact object got scattered in close enough to the MBH to start losing appreciable energy and angular momentum by gravitational radiation. For WDs or NSs, it had been found in most cases that the object would be perturbed considerably by other stars in the cusp before much energy had been lost. Thus the angular momentum would either increase enough so that gravitational radiation would be cut off, or would decrease enough so that the WD or NS would plunge into the MBH in just a few revolutions. The latter event would mean that the signal-to noise ratio would not have time to build up, and the event would not be detectable. The ratio of gradual energy loss events to plunges was found to be roughly one to a few percent, and thus substantially decreased the expected rate of detectable events.

  15. Innovations in high rate condensate polishing systems

    SciTech Connect

    O`Brien, M.

    1995-01-01

    Test work is being conducted at two major east coast utilities to evaluate flow distribution in high flow rate condensate polishing service vessels. The work includes core sample data used to map the flow distribution in vessels as originally manufactured. Underdrain modifications for improved flow distribution are discussed with data that indicates performance increases of the service vessel following the modifications. The test work is on going, with preliminary data indicating that significant improvements in cycle run length are possible with underdrain modifications. The economic benefits of the above modifications are discussed.

  16. Modelling high data rate communication network access protocol

    NASA Technical Reports Server (NTRS)

    Khanna, S.; Foudriat, E. C.; Paterra, Frank; Maly, Kurt J.; Overstreet, C. Michael

    1990-01-01

    Modeling of high data rate communication systems is different from the low data rate systems. Three simulations were built during the development phase of Carrier Sensed Multiple Access/Ring Network (CSMA/RN) modeling. The first was a model using SIMCRIPT based upon the determination and processing of each event at each node. The second simulation was developed in C based upon isolating the distinct object that can be identified as the ring, the message, the node, and the set of critical events. The third model further identified the basic network functionality by creating a single object, the node which includes the set of critical events which occur at the node. The ring structure is implicit in the node structure. This model was also built in C. Each model is discussed and their features compared. It should be stated that the language used was mainly selected by the model developer because of his past familiarity. Further the models were not built with the intent to compare either structure or language but because the complexity of the problem and initial results contained obvious errors, so alternative models were built to isolate, determine, and correct programming and modeling errors. The CSMA/RN protocol is discussed in sufficient detail to understand modeling complexities. Each model is described along with its features and problems. The models are compared and concluding observations and remarks are presented.

  17. High performance static latches with complete single event upset immunity

    DOEpatents

    Corbett, W.T.; Weaver, H.T.

    1994-04-26

    An asymmetric response latch providing immunity to single event upset without loss of speed is described. The latch has cross-coupled inverters having a hardened logic state and a soft state, wherein the logic state of the first inverter can only be changed when the voltage on the coupling node of that inverter is low and the logic state of the second inverter can only be changed when the coupling of that inverter is high. One of more of the asymmetric response latches may be configured into a memory cell having complete immunity, which protects information rather than logic states. 5 figures.

  18. High performance static latches with complete single event upset immunity

    DOEpatents

    Corbett, Wayne T.; Weaver, Harry T.

    1994-01-01

    An asymmetric response latch providing immunity to single event upset without loss of speed. The latch has cross-coupled inverters having a hardened logic state and a soft state, wherein the logic state of the first inverter can only be changed when the voltage on the coupling node of that inverter is low and the logic state of the second inverter can only be changed when the coupling of that inverter is high. One of more of the asymmetric response latches may be configured into a memory cell having complete immunity, which protects information rather than logic states.

  19. High resolution modelling of extreme precipitation events in urban areas

    NASA Astrophysics Data System (ADS)

    Siemerink, Martijn; Volp, Nicolette; Schuurmans, Wytze; Deckers, Dave

    2015-04-01

    The present day society needs to adjust to the effects of climate change. More extreme weather conditions are expected, which can lead to longer periods of drought, but also to more extreme precipitation events. Urban water systems are not designed for such extreme events. Most sewer systems are not able to drain the excessive storm water, causing urban flooding. This leads to high economic damage. In order to take appropriate measures against extreme urban storms, detailed knowledge about the behaviour of the urban water system above and below the streets is required. To investigate the behaviour of urban water systems during extreme precipitation events new assessment tools are necessary. These tools should provide a detailed and integral description of the flow in the full domain of overland runoff, sewer flow, surface water flow and groundwater flow. We developed a new assessment tool, called 3Di, which provides detailed insight in the urban water system. This tool is based on a new numerical methodology that can accurately deal with the interaction between overland runoff, sewer flow and surface water flow. A one-dimensional model for the sewer system and open channel flow is fully coupled to a two-dimensional depth-averaged model that simulates the overland flow. The tool uses a subgrid-based approach in order to take high resolution information of the sewer system and of the terrain into account [1, 2]. The combination of using the high resolution information and the subgrid based approach results in an accurate and efficient modelling tool. It is now possible to simulate entire urban water systems using extreme high resolution (0.5m x 0.5m) terrain data in combination with a detailed sewer and surface water network representation. The new tool has been tested in several Dutch cities, such as Rotterdam, Amsterdam and The Hague. We will present the results of an extreme precipitation event in the city of Schiedam (The Netherlands). This city deals with

  20. Childhood events and circumstances influencing high school completion.

    PubMed

    Haveman, R; Wolfe, B; Spaulding, J

    1991-02-01

    This paper is an empirical exploration of the effects of a variety of family and economic circumstances experienced during childhood on one indicator of success in young adulthood--high school completion. The estimates suggest that parental education and mother's work are positive and significant determinants of high school completion, whereas growing up in a family with more children (who compete for resources), being persistently poor and on welfare, and moving one's residence as a child have significant negative impacts on high school completion. The effects of some family stress and economic events differ depending on the age of the child when they occur. The results support the economic model of investment in children, as well as the welfare culture and socialization models.

  1. Cervix cancer brachytherapy: high dose rate.

    PubMed

    Miglierini, P; Malhaire, J-P; Goasduff, G; Miranda, O; Pradier, O

    2014-10-01

    Cervical cancer, although less common in industrialized countries, is the fourth most common cancer affecting women worldwide and the fourth leading cause of cancer death. In developing countries, these cancers are often discovered at a later stage in the form of locally advanced tumour with a poor prognosis. Depending on the stage of the disease, treatment is mainly based on a chemoradiotherapy followed by uterovaginal brachytherapy ending by a potential remaining tumour surgery or in principle for some teams. The role of irradiation is crucial to ensure a better local control. It has been shown that the more the delivered dose is important, the better the local results are. In order to preserve the maximum of organs at risk and to allow this dose escalation, brachytherapy (intracavitary and/or interstitial) has been progressively introduced. Its evolution and its progressive improvement have led to the development of high dose rate brachytherapy, the advantages of which are especially based on the possibility of outpatient treatment while maintaining the effectiveness of other brachytherapy forms (i.e., low dose rate or pulsed dose rate). Numerous innovations have also been completed in the field of imaging, leading to a progress in treatment planning systems by switching from two-dimensional form to a three-dimensional one. Image-guided brachytherapy allows more precise target volume delineation as well as an optimized dosimetry permitting a better coverage of target volumes.

  2. High resolution Ge/Li/ spectrometer reduces rate-dependent distortions at high counting rates

    NASA Technical Reports Server (NTRS)

    Brenner, R.; Larsen, R. N.; Mann, H. M.; Rudnick, S. J.; Sherman, I. S.; Strauss, M. G.

    1968-01-01

    Modified spectrometer system with a low-noise preamplifier reduces rate-dependent distortions at high counting rates, 25,000 counts per second. Pole-zero cancellation minimizes pulse undershoots due to multiple time constants, baseline restoration improves resolution and prevents spectral shifts.

  3. High-Rate Digital Receiver Board

    NASA Technical Reports Server (NTRS)

    Ghuman, Parminder; Bialas, Thomas; Brambora, Clifford; Fisher, David

    2004-01-01

    A high-rate digital receiver (HRDR) implemented as a peripheral component interface (PCI) board has been developed as a prototype of compact, general-purpose, inexpensive, potentially mass-producible data-acquisition interfaces between telemetry systems and personal computers. The installation of this board in a personal computer together with an analog preprocessor enables the computer to function as a versatile, highrate telemetry-data-acquisition and demodulator system. The prototype HRDR PCI board can handle data at rates as high as 600 megabits per second, in a variety of telemetry formats, transmitted by diverse phase-modulation schemes that include binary phase-shift keying and various forms of quadrature phaseshift keying. Costing less than $25,000 (as of year 2003), the prototype HRDR PCI board supplants multiple racks of older equipment that, when new, cost over $500,000. Just as the development of standard network-interface chips has contributed to the proliferation of networked computers, it is anticipated that the development of standard chips based on the HRDR could contribute to reductions in size and cost and increases in performance of telemetry systems.

  4. High dose rate brachytherapy for oral cancer

    PubMed Central

    YamazakI, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. PMID:23179377

  5. Search for Electronic Recoil Event Rate Modulation with 4 Years of XENON100 Data.

    PubMed

    Aprile, E; Aalbers, J; Agostini, F; Alfonsi, M; Amaro, F D; Anthony, M; Arneodo, F; Barrow, P; Baudis, L; Bauermeister, B; Benabderrahmane, M L; Berger, T; Breur, P A; Brown, A; Brown, E; Bruenner, S; Bruno, G; Budnik, R; Bütikofer, L; Calvén, J; Cardoso, J M R; Cervantes, M; Cichon, D; Coderre, D; Colijn, A P; Conrad, J; Cussonneau, J P; Decowski, M P; de Perio, P; Di Gangi, P; Di Giovanni, A; Diglio, S; Eurin, G; Fei, J; Ferella, A D; Fieguth, A; Franco, D; Fulgione, W; Gallo Rosso, A; Galloway, M; Gao, F; Garbini, M; Geis, C; Goetzke, L W; Greene, Z; Grignon, C; Hasterok, C; Hogenbirk, E; Itay, R; Kaminsky, B; Kessler, G; Kish, A; Landsman, H; Lang, R F; Lellouch, D; Levinson, L; Lin, Q; Lindemann, S; Lindner, M; Lopes, J A M; Manfredini, A; Maris, I; Marrodán Undagoitia, T; Masbou, J; Massoli, F V; Masson, D; Mayani, D; Messina, M; Micheneau, K; Miguez, B; Molinario, A; Murra, M; Naganoma, J; Ni, K; Oberlack, U; Pakarha, P; Pelssers, B; Persiani, R; Piastra, F; Pienaar, J; Pizzella, V; Piro, M-C; Plante, G; Priel, N; Rauch, L; Reichard, S; Reuter, C; Rizzo, A; Rosendahl, S; Rupp, N; Dos Santos, J M F; Sartorelli, G; Scheibelhut, M; Schindler, S; Schreiner, J; Schumann, M; Scotto Lavina, L; Selvi, M; Shagin, P; Silva, M; Simgen, H; Sivers, M V; Stein, A; Thers, D; Tiseni, A; Trinchero, G; Tunnell, C; Wang, H; Wei, Y; Weinheimer, C; Wulf, J; Ye, J; Zhang, Y

    2017-03-10

    We report on a search for electronic recoil event rate modulation signatures in the XENON100 data accumulated over a period of 4 yr, from January 2010 to January 2014. A profile likelihood method, which incorporates the stability of the XENON100 detector and the known electronic recoil background model, is used to quantify the significance of periodicity in the time distribution of events. There is a weak modulation signature at a period of 431_{-14}^{+16} day in the low energy region of (2.0-5.8) keV in the single scatter event sample, with a global significance of 1.9σ; however, no other more significant modulation is observed. The significance of an annual modulation signature drops from 2.8σ, from a previous analysis of a subset of this data, to 1.8σ with all data combined. Single scatter events in the low energy region are thus used to exclude the DAMA/LIBRA annual modulation as being due to dark matter electron interactions via axial vector coupling at 5.7σ.

  6. Search for Electronic Recoil Event Rate Modulation with 4 Years of XENON100 Data

    NASA Astrophysics Data System (ADS)

    Aprile, E.; Aalbers, J.; Agostini, F.; Alfonsi, M.; Amaro, F. D.; Anthony, M.; Arneodo, F.; Barrow, P.; Baudis, L.; Bauermeister, B.; Benabderrahmane, M. L.; Berger, T.; Breur, P. A.; Brown, A.; Brown, E.; Bruenner, S.; Bruno, G.; Budnik, R.; Bütikofer, L.; Calvén, J.; Cardoso, J. M. R.; Cervantes, M.; Cichon, D.; Coderre, D.; Colijn, A. P.; Conrad, J.; Cussonneau, J. P.; Decowski, M. P.; de Perio, P.; di Gangi, P.; di Giovanni, A.; Diglio, S.; Eurin, G.; Fei, J.; Ferella, A. D.; Fieguth, A.; Franco, D.; Fulgione, W.; Gallo Rosso, A.; Galloway, M.; Gao, F.; Garbini, M.; Geis, C.; Goetzke, L. W.; Greene, Z.; Grignon, C.; Hasterok, C.; Hogenbirk, E.; Itay, R.; Kaminsky, B.; Kessler, G.; Kish, A.; Landsman, H.; Lang, R. F.; Lellouch, D.; Levinson, L.; Lin, Q.; Lindemann, S.; Lindner, M.; Lopes, J. A. M.; Manfredini, A.; Maris, I.; Marrodán Undagoitia, T.; Masbou, J.; Massoli, F. V.; Masson, D.; Mayani, D.; Messina, M.; Micheneau, K.; Miguez, B.; Molinario, A.; Murra, M.; Naganoma, J.; Ni, K.; Oberlack, U.; Pakarha, P.; Pelssers, B.; Persiani, R.; Piastra, F.; Pienaar, J.; Pizzella, V.; Piro, M.-C.; Plante, G.; Priel, N.; Rauch, L.; Reichard, S.; Reuter, C.; Rizzo, A.; Rosendahl, S.; Rupp, N.; Dos Santos, J. M. F.; Sartorelli, G.; Scheibelhut, M.; Schindler, S.; Schreiner, J.; Schumann, M.; Scotto Lavina, L.; Selvi, M.; Shagin, P.; Silva, M.; Simgen, H.; Sivers, M. V.; Stein, A.; Thers, D.; Tiseni, A.; Trinchero, G.; Tunnell, C.; Wang, H.; Wei, Y.; Weinheimer, C.; Wulf, J.; Ye, J.; Zhang, Y.; Xenon Collaboration

    2017-03-01

    We report on a search for electronic recoil event rate modulation signatures in the XENON100 data accumulated over a period of 4 yr, from January 2010 to January 2014. A profile likelihood method, which incorporates the stability of the XENON100 detector and the known electronic recoil background model, is used to quantify the significance of periodicity in the time distribution of events. There is a weak modulation signature at a period of 43 1-14+16 day in the low energy region of (2.0-5.8) keV in the single scatter event sample, with a global significance of 1.9 σ ; however, no other more significant modulation is observed. The significance of an annual modulation signature drops from 2.8 σ , from a previous analysis of a subset of this data, to 1.8 σ with all data combined. Single scatter events in the low energy region are thus used to exclude the DAMA/LIBRA annual modulation as being due to dark matter electron interactions via axial vector coupling at 5.7 σ .

  7. High Probabilities of Planet Detection during Microlensing Events.

    NASA Astrophysics Data System (ADS)

    Peale, S. J.

    2000-10-01

    The averaged probability of detecting a planetary companion of a lensing star during a gravitational microlensing event toward the Galactic center when the planet-lens mass ratio is 0.001 is shown to have a maximum exceeding 20% for a distribution of source-lens impact parameters that is determined by the efficiency of event detection, and a maximum exceeding 10% for a uniform distribution of impact parameters. The probability varies as the square root of the planet-lens mass ratio. A planet is assumed detectable if the perturbation of the light curve exceeds 2/(S/N) for a significant number of data points, where S/N is the signal-to noise ratio for the photometry of the source. The probability peaks at a planetary semimajor axis a that is close to the mean Einstein ring radius of the lenses of about 2 AU along the line of sight, and remains significant for 0.6<= a<= 10 AU. The low value of the mean Einstein ring radius results from the dominance of M stars in the mass function of the lenses. The probability is averaged over the distribution of the projected position of the planet onto the lens plane, over the lens mass function, over the distribution of impact parameters, over the distribution of lens along the line of sight to the source star, over the I band luminosity function of the sources adjusted for the source distance, and over the source distribution along the line of sight. If two or more parameters of the lensing event are known, such as the I magnitude of the source and the impact parameter, the averages over these parameters can be omitted and the probability of detection determined for a particular event. The calculated probabilities behave as expected with variations in the line of sight, the mass function of the lenses, the extinction and distance to and magnitude of the source, and with a more demanding detection criterion. The relatively high values of the probabilities are robust to plausible variations in the assumptions. The high

  8. Hypoglycemia Event Rates: A Comparison Between Real-World Data and Randomized Controlled Trial Populations in Insulin-Treated Diabetes.

    PubMed

    Elliott, Lisa; Fidler, Carrie; Ditchfield, Andrea; Stissing, Trine

    2016-03-01

    Hypoglycemia is the most common adverse effect of diabetes therapy, particularly insulin treatment. Hypoglycemia is associated with considerable clinical and economic burden, and may be under-reported. The aim of this study was to com pare the frequency of hypoglycemic events reported in real-world settings with those reported in clinical trials. We conducted a structured literature review in PubMed to identify hypoglycemic event rates in patients with type 1 diabetes mellitus (T1DM) and insulin-treated type 2 diabetes mellitus (T2DM) from real-world data (RWD) and randomized controlled trials (RCTs). The search was restricted to English language, full-text publications from 2010 onwards, reporting on treatment of T1DM or T2DM with basal only, basal-bolus, or premix insulin. The final dataset included 30 studies (11 RWD studies and 19 RCTs). Six studies (RWD, n = 2; RCT, n = 4) reported hypoglycemia event rates in people with T1DM. For all reported categories of hypoglycemia (severe, non-severe, and nocturnal), rates were consistently higher in RWD studies compared with RCTs. Twenty-five studies (RWD, n = 10; RCT, n = 15) reported hypoglycemia event rates in people with insulin-treated T2DM. For T2DM basal-oral therapy; the highest rates were observed in RWD studies, although there was an overlap with RCT rates. For basal-bolus therapy, there was considerable between-study variability but higher rates of severe and non-severe hypoglycemia were generally observed in RWD studies. For T2DM premix insulin, reported rates of hypoglycemia in RWD studies and RCTs were similar. We found that higher rates of hypoglycemia are observed in real-world settings compared with clinical trial settings, although there is a large degree of overlap. Due to the inherent constraints of RCTs, they are likely to underestimate the burden of hypoglycemia in clinical practice. Further, high-quality RWD are needed to determine a more accurate incidence of hypoglycemia in clinical

  9. Inference on the rate ratio of recurrent events for the matched pairs design.

    PubMed

    Sumi, Mariko; Tango, Toshiro

    2010-12-30

    As statistical methods for testing the null hypothesis of no difference between two groups for the matched pairs design, the paired-t test, Wilcoxon signed rank sum test and McNemar test are well known. However, there is no simple test for the comparison of incidence rate of recurrent events. This paper proposes a simple statistical method and a sample size formula for the comparison of counts of recurrent events over a specified period of observation under the matched pairs design, where the subject-specific incidence of recurrent events is assumed to follow a time-homogeneous Poisson process. As a special case, the proposed method is found to be virtually equivalent in form to Mantel-Haenszel method for a common rate ratio among the set of stratified tables based on person-time data. The proposed methods are illustrated with the within-arm comparison of data from a clinical trial of 59 epileptics with baseline count data. Copyright © 2010 John Wiley & Sons, Ltd.

  10. Financial system loss as an example of high consequence, high frequency events

    SciTech Connect

    McGovern, D.E.

    1996-07-01

    Much work has been devoted to high consequence events with low frequency of occurrence. Characteristic of these events are bridge failure (such as that of the Tacoma Narrows), building failure (such as the collapse of a walkway at a Kansas City hotel), or compromise of a major chemical containment system (such as at Bhopal, India). Such events, although rare, have an extreme personal, societal, and financial impact. An interesting variation is demonstrated by financial losses due to fraud and abuse in the money management system. The impact can be huge, entailing very high aggregate costs, but these are a result of the contribution of many small attacks and not the result of a single (or few) massive events. Public awareness is raised through publicized events such as the junk bond fraud perpetrated by Milikin or gross mismanagement in the failure of the Barings Bank through unsupervised trading activities by Leeson in Singapore. These event,s although seemingly large (financial losses may be on the order of several billion dollars), are but small contributors to the estimated $114 billion loss to all types of financial fraud in 1993. This paper explores the magnitude of financial system losses and identifies new areas for analysis of high consequence events including the potential effect of malevolent intent.

  11. Summary of Aqua, Aura, and Terra High Interest Events

    NASA Technical Reports Server (NTRS)

    Newman, Lauri

    2015-01-01

    Single-obs tracking Sparsely tracked objects are an unfortunate reality of CARA operations Terra vs. 32081: new track with bad data was included in OD solution for secondary object and risk became high CARA and JSpOC discussed tracking and OSAs threw out the bad data. Event no longer presented high risk based on new OD Improvement: CARA now sends JSpOC a flag indicating when a single obs is included, so OSAs can evaluate if manual update to OD is required. Missing ASW OCMsAura vs. 87178, TCA: 317 at 08:04 UTC. Post-maneuver risk (conjunction was identified in OO results)CARA confirmed with JSpOC that ASW OCMs should have been received in addition to OO OCMsJSpOC corrected the manual error in their script that prevented the data from being delivered to CARAJSpOC QAd their other scripts to ensure this error did not exist in other places.

  12. The "Sapienza University Mortality and Morbidity Event Rate (SUMMER) study in diabetes": Study protocol.

    PubMed

    Barchetta, I; Capoccia, D; Baroni, M G; Buzzetti, R; Cavallo, M G; De Cosmo, S; Leonetti, F; Leotta, S; Morano, S; Morviducci, L; Prudente, S; Pugliese, G; Trischitta, V

    2016-02-01

    The rate of mortality in diabetic patients, especially of cardiovascular origin, is about twice as much that of nondiabetic individuals. Thus, the pathogenic factors shaping the risk of mortality in such patients must be unraveled in order to target intensive prevention and treatment strategies. The "Sapienza University Mortality and Morbidity Event Rate (SUMMER) study in diabetes" is aimed at identifying new molecular promoters of mortality and major vascular events in patients with type 2 diabetes mellitus (T2DM). The "SUMMER study in diabetes" is an observational, prospective, and collaborative study conducted on at least 5000 consecutive patients with T2DM, recruited from several diabetes clinics of Central-Southern Italy and followed up for a minimum of 5 years. The primary outcome is all-cause mortality; the secondary outcomes are cardiovascular mortality, acute myocardial infarction, stroke, and dialysis. A biobank will be created for genomic, transcriptomic, and metabolomic analysis, in order to unravel new molecular predictors of mortality and vascular morbidity. The "SUMMER study in diabetes" is aimed at identifying new molecular promoters of mortality and major vascular events in patients with T2DM. These novel pathogenic factors will most likely be instrumental in unraveling new pathways underlying such dramatic events. In addition, they will also be used as additional markers to increase the performance of the already existing risk-scoring models for predicting the above-mentioned outcomes in T2DM, as well as for setting up new preventive and treatment strategies, possibly tailored to specific pathogenic backgrounds. ClinicalTrials.gov, NCT02311244; URL https://clinicaltrials.gov/ct2/show/NCT02311244?term=SUMMER&rank=5. Copyright © 2015 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published

  13. The effects of hydraulics, geomorphology, and storm events on metabolism rates in an agricultural river

    NASA Astrophysics Data System (ADS)

    O'Connor, B. L.; Harvey, J. W.; McPhillips, L. E.

    2009-12-01

    Physical factors such as discharge, geomorphology, and sediment transport strongly influence metabolism rates in agricultural rivers with sparse tree canopies where sunlight is not limiting. These physical processes establish a mosaic of sediment habitats of varying particle sizes, permeabilities, and biological communities that control primary production and respiration rates. In this study, we examined the combined factors of hydraulic conditions, sediment texture, and hyporheic exchange on the spatial and temporal variability of metabolism rates in an agricultural river located in central Iowa. Hydraulic conditions were quantified using field velocity measurements and two-dimensional hydraulic modeling. Sediment texture was assessed using a grid-based survey identifying dominant particle size classes, as well as aerial coverage of green algae and fine benthic organic material. Hyporheic exchange potential was quantified using an effective diffusion scaling relationship based on sediment and flow conditions. Patch-scale metabolism rates varied spatially according to patterns in hydraulic and sediment characteristics, but were of the same order of magnitude as reach-scale gross primary productivity and community respiration measurements. Two discharge-related storm perturbation regimes to the reach-scale metabolism rates were identified using diurnal dissolved oxygen data measured at the study reach over three years. Rainfall events of < 3 cm disrupted the metabolism rates for 1-2 days as a result of increased turbidity, whereas rainfall events of > 3 cm disrupted metabolism rates for several days to weeks due to bed mobilization and the restructuring of the sediment habitats. A combination of hydraulic modeling, habitat mapping, and reach-scale metabolism measurements were used to produce a two-dimensional analysis of a turbidity-related disturbance event that occurred in late fall 2007. Results from this study suggest that physical processes establish, destroy

  14. Comparative determinants of 4-year cardiovascular event rates in stable outpatients at risk of or with atherothrombosis.

    PubMed

    Bhatt, Deepak L; Eagle, Kim A; Ohman, E Magnus; Hirsch, Alan T; Goto, Shinya; Mahoney, Elizabeth M; Wilson, Peter W F; Alberts, Mark J; D'Agostino, Ralph; Liau, Chiau-Suong; Mas, Jean-Louis; Röther, Joachim; Smith, Sidney C; Salette, Geneviève; Contant, Charles F; Massaro, Joseph M; Steg, Ph Gabriel

    2010-09-22

    Clinicians and trialists have difficulty with identifying which patients are highest risk for cardiovascular events. Prior ischemic events, polyvascular disease, and diabetes mellitus have all been identified as predictors of ischemic events, but their comparative contributions to future risk remain unclear. To categorize the risk of cardiovascular events in stable outpatients with various initial manifestations of atherothrombosis using simple clinical descriptors. Outpatients with coronary artery disease, cerebrovascular disease, or peripheral arterial disease or with multiple risk factors for atherothrombosis were enrolled in the global Reduction of Atherothrombosis for Continued Health (REACH) Registry and were followed up for as long as 4 years. Patients from 3647 centers in 29 countries were enrolled between 2003 and 2004 and followed up until 2008. Final database lock was in April 2009. Rates of cardiovascular death, myocardial infarction, and stroke. A total of 45,227 patients with baseline data were included in this 4-year analysis. During the follow-up period, a total of 5481 patients experienced at least 1 event, including 2315 with cardiovascular death, 1228 with myocardial infarction, 1898 with stroke, and 40 with both a myocardial infarction and stroke on the same day. Among patients with atherothrombosis, those with a prior history of ischemic events at baseline (n = 21,890) had the highest rate of subsequent ischemic events (18.3%; 95% confidence interval [CI], 17.4%-19.1%); patients with stable coronary, cerebrovascular, or peripheral artery disease (n = 15,264) had a lower risk (12.2%; 95% CI, 11.4%-12.9%); and patients without established atherothrombosis but with risk factors only (n = 8073) had the lowest risk (9.1%; 95% CI, 8.3%-9.9%) (P < .001 for all comparisons). In addition, in multivariable modeling, the presence of diabetes (hazard ratio [HR], 1.44; 95% CI, 1.36-1.53; P < .001), an ischemic event in the previous year (HR, 1.71; 95% CI, 1

  15. High spin rate magnetic controller for nanosatellites

    NASA Astrophysics Data System (ADS)

    Slavinskis, A.; Kvell, U.; Kulu, E.; Sünter, I.; Kuuste, H.; Lätt, S.; Voormansik, K.; Noorma, M.

    2014-02-01

    This paper presents a study of a high rate closed-loop spin controller that uses only electromagnetic coils as actuators. The controller is able to perform spin rate control and simultaneously align the spin axis with the Earth's inertial reference frame. It is implemented, optimised and simulated for a 1-unit CubeSat ESTCube-1 to fulfil its mission requirements: spin the satellite up to 360 deg s-1 around the z-axis and align its spin axis with the Earth's polar axis with a pointing error of less than 3°. The attitude of the satellite is determined using a magnetic field vector, a Sun vector and angular velocity. It is estimated using an Unscented Kalman Filter and controlled using three electromagnetic coils. The algorithm is tested in a simulation environment that includes models of space environment and environmental disturbances, sensor and actuator emulation, attitude estimation, and a model to simulate the time delay caused by on-board calculations. In addition to the normal operation mode, analyses of reduced satellite functionality are performed: significant errors of attitude estimation due to non-operational Sun sensors; and limited actuator functionality due to two non-operational coils. A hardware-in-the-loop test is also performed to verify on-board software.

  16. Application of high-rate cutting tools

    NASA Astrophysics Data System (ADS)

    Moriarty, John L., Jr.

    1989-03-01

    Widespread application of the newest high-rate cutting tools to the most appropriate jobs is slowed by the sheer magnitude of developments in tool types, materials, workpiece applications, and by the rapid pace of change. Therefore, a study of finishing and roughing sizes of coated carbide inserts having a variety of geometries for single point turning was completed. The cutting tools were tested for tool life, chip quality, and workpiece surface finish at various cutting conditions with medium alloy steel. An empirical wear-life data base was established, and a computer program was developed to facilitate technology transfer, assist selection of carbide insert grades, and provide machine operating parameters. A follow-on test program was implemented suitable for next generation coated carbides, rotary cutting tools, cutting fluids, and ceramic tool materials.

  17. Heart Rate Deceleration as a Function of Viewing Complex Visual Events in Eighteen-Month-Old Infants.

    ERIC Educational Resources Information Center

    Gilmore, Lowry M.; And Others

    This research project assessed: (1) the practicality of recording heart rate in 18-month-old infants as they watched events filmed on color, silent motion picture films; and (2) the validity and sensitivity of heart rate change as an index of differential attention arousal elicited by changes within and between complex visual events. The research…

  18. Cardiovascular risk and events in 17 low-, middle-, and high-income countries.

    PubMed

    Yusuf, Salim; Rangarajan, Sumathy; Teo, Koon; Islam, Shofiqul; Li, Wei; Liu, Lisheng; Bo, Jian; Lou, Qinglin; Lu, Fanghong; Liu, Tianlu; Yu, Liu; Zhang, Shiying; Mony, Prem; Swaminathan, Sumathi; Mohan, Viswanathan; Gupta, Rajeev; Kumar, Rajesh; Vijayakumar, Krishnapillai; Lear, Scott; Anand, Sonia; Wielgosz, Andreas; Diaz, Rafael; Avezum, Alvaro; Lopez-Jaramillo, Patricio; Lanas, Fernando; Yusoff, Khalid; Ismail, Noorhassim; Iqbal, Romaina; Rahman, Omar; Rosengren, Annika; Yusufali, Afzalhussein; Kelishadi, Roya; Kruger, Annamarie; Puoane, Thandi; Szuba, Andrzej; Chifamba, Jephat; Oguz, Aytekin; McQueen, Matthew; McKee, Martin; Dagenais, Gilles

    2014-08-28

    More than 80% of deaths from cardiovascular disease are estimated to occur in low-income and middle-income countries, but the reasons are unknown. We enrolled 156,424 persons from 628 urban and rural communities in 17 countries (3 high-income, 10 middle-income, and 4 low-income countries) and assessed their cardiovascular risk using the INTERHEART Risk Score, a validated score for quantifying risk-factor burden without the use of laboratory testing (with higher scores indicating greater risk-factor burden). Participants were followed for incident cardiovascular disease and death for a mean of 4.1 years. The mean INTERHEART Risk Score was highest in high-income countries, intermediate in middle-income countries, and lowest in low-income countries (P<0.001). However, the rates of major cardiovascular events (death from cardiovascular causes, myocardial infarction, stroke, or heart failure) were lower in high-income countries than in middle- and low-income countries (3.99 events per 1000 person-years vs. 5.38 and 6.43 events per 1000 person-years, respectively; P<0.001). Case fatality rates were also lowest in high-income countries (6.5%, 15.9%, and 17.3% in high-, middle-, and low-income countries, respectively; P=0.01). Urban communities had a higher risk-factor burden than rural communities but lower rates of cardiovascular events (4.83 vs. 6.25 events per 1000 person-years, P<0.001) and case fatality rates (13.52% vs. 17.25%, P<0.001). The use of preventive medications and revascularization procedures was significantly more common in high-income countries than in middle- or low-income countries (P<0.001). Although the risk-factor burden was lowest in low-income countries, the rates of major cardiovascular disease and death were substantially higher in low-income countries than in high-income countries. The high burden of risk factors in high-income countries may have been mitigated by better control of risk factors and more frequent use of proven pharmacologic

  19. Ascidian Mitogenomics: Comparison of Evolutionary Rates in Closely Related Taxa Provides Evidence of Ongoing Speciation Events

    PubMed Central

    Griggio, Francesca; Voskoboynik, Ayelet; Iannelli, Fabio; Justy, Fabienne; Tilak, Marie-Ka; Xavier, Turon; Pesole, Graziano; Douzery, Emmanuel J.P.; Mastrototaro, Francesco; Gissi, Carmela

    2014-01-01

    Ascidians are a fascinating group of filter-feeding marine chordates characterized by rapid evolution of both sequences and structure of their nuclear and mitochondrial genomes. Moreover, they include several model organisms used to investigate complex biological processes in chordates. To study the evolutionary dynamics of ascidians at short phylogenetic distances, we sequenced 13 new mitogenomes and analyzed them, together with 15 other available mitogenomes, using a novel approach involving detailed whole-mitogenome comparisons of conspecific and congeneric pairs. The evolutionary rate was quite homogeneous at both intraspecific and congeneric level, and the lowest congeneric rates were found in cryptic (morphologically undistinguishable) and in morphologically very similar species pairs. Moreover, congeneric nonsynonymous rates (dN) were up to two orders of magnitude higher than in intraspecies pairs. Overall, a clear-cut gap sets apart conspecific from congeneric pairs. These evolutionary peculiarities allowed easily identifying an extraordinary intraspecific variability in the model ascidian Botryllus schlosseri, where most pairs show a dN value between that observed at intraspecies and congeneric level, yet consistently lower than that of the Ciona intestinalis cryptic species pair. These data suggest ongoing speciation events producing genetically distinct B. schlosseri entities. Remarkably, these ongoing speciation events were undetectable by the cox1 barcode fragment, demonstrating that, at low phylogenetic distances, the whole mitogenome has a higher resolving power than cox1. Our study shows that whole-mitogenome comparative analyses, performed on a suitable sample of congeneric and intraspecies pairs, may allow detecting not only cryptic species but also ongoing speciation events. PMID:24572017

  20. Multianode cylindrical proportional counter for high count rates

    DOEpatents

    Hanson, J.A.; Kopp, M.K.

    1980-05-23

    A cylindrical, multiple-anode proportional counter is provided for counting of low-energy photons (< 60 keV) at count rates of greater than 10/sup 5/ counts/sec. A gas-filled proportional counter cylinder forming an outer cathode is provided with a central coaxially disposed inner cathode and a plurality of anode wires disposed in a cylindrical array in coaxial alignment with and between the inner and outer cathodes to form a virtual cylindrical anode coaxial with the inner and outer cathodes. The virtual cylindrical anode configuration improves the electron drift velocity by providing a more uniform field strength throughout the counter gas volume, thus decreasing the electron collection time following the detection of an ionizing event. This avoids pulse pile-up and coincidence losses at these high count rates. Conventional RC position encoding detection circuitry may be employed to extract the spatial information from the counter anodes.

  1. Multianode cylindrical proportional counter for high count rates

    DOEpatents

    Hanson, James A.; Kopp, Manfred K.

    1981-01-01

    A cylindrical, multiple-anode proportional counter is provided for counting of low-energy photons (<60 keV) at count rates of greater than 10.sup.5 counts/sec. A gas-filled proportional counter cylinder forming an outer cathode is provided with a central coaxially disposed inner cathode and a plurality of anode wires disposed in a cylindrical array in coaxial alignment with and between the inner and outer cathodes to form a virtual cylindrical anode coaxial with the inner and outer cathodes. The virtual cylindrical anode configuration improves the electron drift velocity by providing a more uniform field strength throughout the counter gas volume, thus decreasing the electron collection time following the detection of an ionizing event. This avoids pulse pile-up and coincidence losses at these high count rates. Conventional RC position encoding detection circuitry may be employed to extract the spatial information from the counter anodes.

  2. Low resistance bakelite RPC study for high rate working capability

    DOE PAGES

    Dai, T.; Han, L.; Hou, S.; ...

    2014-11-19

    This paper presents series efforts to lower resistance of bakelite electrode plate to improve the RPC capability under high rate working condition. New bakelite material with alkali metallic ion doping has been manufactured and tested. This bakelite is found unstable under large charge flux and need further investigation. A new structure of carbon-embedded bakelite RPC has been developed, which can reduce the effective resistance of electrode by a factor of 10. The prototype of the carbon-embedded chamber could function well under gamma radiation source at event rate higher than 10 kHz/cm2. The preliminary tests show that this kind of newmore » structure performs as efficiently as traditional RPCs.« less

  3. Low resistance bakelite RPC study for high rate working capability

    SciTech Connect

    Dai, T.; Han, L.; Hou, S.; Liu, M.; Li, Q.; Song, H.; Xia, L.; Zhang, Z.

    2014-11-19

    This paper presents series efforts to lower resistance of bakelite electrode plate to improve the RPC capability under high rate working condition. New bakelite material with alkali metallic ion doping has been manufactured and tested. This bakelite is found unstable under large charge flux and need further investigation. A new structure of carbon-embedded bakelite RPC has been developed, which can reduce the effective resistance of electrode by a factor of 10. The prototype of the carbon-embedded chamber could function well under gamma radiation source at event rate higher than 10 kHz/cm2. The preliminary tests show that this kind of new structure performs as efficiently as traditional RPCs.

  4. High-level simulation of JWST event-driven operations

    NASA Astrophysics Data System (ADS)

    Henry, R.; Kinzel, W.

    2012-09-01

    The James Webb Space Telescope (JWST) has an event-driven architecture: an onboard Observation Plan Executive (OPE) executes an Observation Plan (OP) consisting of a sequence of observing units (visits). During normal operations, ground action to update the OP is only expected to be necessary about once a week. This architecture is designed to tolerate uncertainty in visit duration, and occasional visit failures due to inability to acquire guide stars, without creating gaps in the observing timeline. The operations concept is complicated by the need for occasional scheduling of timecritical science and engineering visits that cannot tolerate much slippage without inducing gaps, and also by onboard momentum management. A prototype Python tool called the JWST Observation Plan Execution Simulator (JOPES) has recently been developed to simulate OP execution at a high level and analyze the response of the Observatory and OPE to both nominal and contingency scenarios. Incorporating both deterministic and stochastic behavior, JOPES has potential to be a powerful tool for several purposes: requirements analysis, system verification, systems engineering studies, and test data generation. It has already been successfully applied to a study of overhead estimation bias: whether to use conservative or average-case estimates for timing components that are inherently uncertain, such as those involving guide-star acquisition. JOPES is being enhanced to support interfaces to the operational Proposal Planning Subsystem (PPS) now being developed, with the objective of "closing the loop" between testing and simulation by feeding simulated event logs back into the PPS.

  5. High Data Rate Architecture (HiDRA)

    NASA Technical Reports Server (NTRS)

    Hylton, Alan; Raible, Daniel

    2016-01-01

    high-rate laser terminals. These must interface with the existing, aging data infrastructure. The High Data Rate Architecture (HiDRA) project is designed to provide networked store, carry, and forward capability to optimize data flow through both the existing radio frequency (RF) and new laser communications terminal. The networking capability is realized through the Delay Tolerant Networking (DTN) protocol, and is used for scheduling data movement as well as optimizing the performance of existing RF channels. HiDRA is realized as a distributed FPGA memory and interface controller that is itself controlled by a local computer running DTN software. Thus HiDRA is applicable to other arenas seeking to employ next-generation communications technologies, e.g. deep space. In this paper, we describe HiDRA and its far-reaching research implications.

  6. Hospitalized Patients at High Risk for Obstructive Sleep Apnea Have More Rapid Response System Events and Intervention Is Associated with Reduced Events

    PubMed Central

    Sharma, Sunil; Chowdhury, Anindita; Tang, Lili; Willes, Leslee; Glynn, Brian; Quan, Stuart F.

    2016-01-01

    Background Rapid response system (RRS) is a safety tool designed for early detection and intervention of a deteriorating patient on the general floor in the hospital. Obstructive sleep apnea (OSA) has been associated with significant cardiovascular complications. We hypothesized that patients with high-risk of OSA have higher rate of RRS events and intervention with positive airway pressure therapy in these patients can mitigate the RRS events. Methods As part of a clinical pathway, during a 15 month period, patients with BMI ≥ 30 kg/m2 in select medical services were screened with a validated sleep questionnaire. Patients were characterized as high or low risk based on the screening questionnaire. RRS rates were compared between the groups. Subsequently the impact of PAP therapy on RRS events was evaluated. Results Out of the 2,590 patients screened, 1,973 (76%) were identified as high-risk. RRS rates calculated per 1,000 admissions, were 43.60 in the High-Risk OSA group versus 25.91 in the Low-Risk OSA Group. The PAP therapy compliant group had significantly reduced RRS event rates compared to non-compliant group and group with no PAP therapy (16.99 vs. 53.40 vs. 56.21) (p < 0.01). Conclusion In a large cohort of patients at a tertiary care hospital, we show an association of increased rate of RRS events in high-risk OSA patients and reduction of the risk with PAP intervention in the compliant group. PMID:27168330

  7. Systematic Uncertainties in High-Rate Germanium Data

    SciTech Connect

    Gilbert, Andrew J.; Fast, James E.; Fulsom, Bryan G.; Pitts, William K.; VanDevender, Brent A.; Wood, Lynn S.

    2016-10-06

    For many nuclear material safeguards inspections, spectroscopic gamma detectors are required which can achieve high event rates (in excess of 10^6 s^-1) while maintaining very good energy resolution for discrimination of neighboring gamma signatures in complex backgrounds. Such spectra can be useful for non-destructive assay (NDA) of spent nuclear fuel with long cooling times, which contains many potentially useful low-rate gamma lines, e.g., Cs-134, in the presence of a few dominating gamma lines, such as Cs-137. Detectors in use typically sacrifice energy resolution for count rate, e.g., LaBr3, or visa versa, e.g., CdZnTe. In contrast, we anticipate that beginning with a detector with high energy resolution, e.g., high-purity germanium (HPGe), and adapting the data acquisition for high throughput will be able to achieve the goals of the ideal detector. In this work, we present quantification of Cs-134 and Cs-137 activities, useful for fuel burn-up quantification, in fuel that has been cooling for 22.3 years. A segmented, planar HPGe detector is used for this inspection, which has been adapted for a high-rate throughput in excess of 500k counts/s. Using a very-high-statistic spectrum of 2.4*10^11 counts, isotope activities can be determined with very low statistical uncertainty. However, it is determined that systematic uncertainties dominate in such a data set, e.g., the uncertainty in the pulse line shape. This spectrum offers a unique opportunity to quantify this uncertainty and subsequently determine required counting times for given precision on values of interest.

  8. Significance of "high probability/low damage" versus "low probability/high damage" flood events

    NASA Astrophysics Data System (ADS)

    Merz, B.; Elmer, F.; Thieken, A. H.

    2009-06-01

    The need for an efficient use of limited resources fosters the application of risk-oriented design in flood mitigation. Flood defence measures reduce future damage. Traditionally, this benefit is quantified via the expected annual damage. We analyse the contribution of "high probability/low damage" floods versus the contribution of "low probability/high damage" events to the expected annual damage. For three case studies, i.e. actual flood situations in flood-prone communities in Germany, it is shown that the expected annual damage is dominated by "high probability/low damage" events. Extreme events play a minor role, even though they cause high damage. Using typical values for flood frequency behaviour, flood plain morphology, distribution of assets and vulnerability, it is shown that this also holds for the general case of river floods in Germany. This result is compared to the significance of extreme events in the public perception. "Low probability/high damage" events are more important in the societal view than it is expressed by the expected annual damage. We conclude that the expected annual damage should be used with care since it is not in agreement with societal priorities. Further, risk aversion functions that penalise events with disastrous consequences are introduced in the appraisal of risk mitigation options. It is shown that risk aversion may have substantial implications for decision-making. Different flood mitigation decisions are probable, when risk aversion is taken into account.

  9. Combining Gravitational Wave Events with their Electromagnetic Counterparts: A Realistic Joint False-Alarm Rate

    NASA Astrophysics Data System (ADS)

    Ackley, Kendall; Eikenberry, Stephen; Klimenko, Sergey; LIGO Team

    2017-01-01

    We present a false-alarm rate for a joint detection of gravitational wave (GW) events and associated electromagnetic (EM) counterparts for Advanced LIGO and Virgo (LV) observations during the first years of operation. Using simulated GW events and their recostructed probability skymaps, we tile over the error regions using sets of archival wide-field telescope survey images and recover the number of astrophysical transients to be expected during LV-EM followup. With the known GW event injection coordinates we inject artificial electromagnetic (EM) sources at that site based on theoretical and observational models on a one-to-one basis. We calculate the EM false-alarm probability using an unsupervised machine learning algorithm based on shapelet analysis which has shown to be a strong discriminator between astrophysical transients and image artifacts while reducing the set of transients to be manually vetted by five orders of magnitude. We also show the performance of our method in context with other machine-learned transient classification and reduction algorithms, showing comparability without the need for a large set of training data opening the possibility for next-generation telescopes to take advantage of this pipeline for LV-EM followup missions.

  10. Variation in the rates of adverse events between hospitals and hospital departments.

    PubMed

    Zegers, Marieke; De Bruijne, Martine C; Spreeuwenberg, Peter; Wagner, Cordula; Van Der Wal, Gerrit; Groenewegen, Peter P

    2011-04-01

    The objective of this study was to analyze the variation in the rates of adverse events (AEs), and preventable AEs, between hospitals and hospital departments in order to investigate the room for improvement in reducing AEs at both levels. In addition, we explored the extent to which patient, department and hospital characteristics explain differences in the rates of AEs. Structured retrospective patient record review of hospital admissions. Twenty-one Dutch hospitals. Population A representative random sample of 7113 hospital admissions in 2004. Variation in AEs, and preventable AEs, between hospitals and hospital departments and the explanatory factors of the variation. The rates of AEs varied between hospitals (P = 0.05) and hospital departments (P < 0.05). The rates of preventable AEs only varied significantly between hospital departments. The clustering of preventable AEs in hospital departments was more than twice that found in hospitals (ICC 9.5 versus 3.5%). The type of hospital explained 35% of the inter-hospital variance in AEs. Patient and department characteristics explained 23% of the inter-department variance in preventable AEs. In addition to interventions to improve the overall patient safety within a hospital, interventions tailored for specific departments are necessary to reduce their patient safety risks. Monitoring and comparing the performance of hospitals should not be limited to the hospital level, but should be extended to the individual department since there can be significant differences in the rates of preventable AEs between different departments within the same hospital.

  11. Rates and genomic consequences of spontaneous mutational events in Drosophila melanogaster.

    PubMed

    Schrider, Daniel R; Houle, David; Lynch, Michael; Hahn, Matthew W

    2013-08-01

    Because spontaneous mutation is the source of all genetic diversity, measuring mutation rates can reveal how natural selection drives patterns of variation within and between species. We sequenced eight genomes produced by a mutation-accumulation experiment in Drosophila melanogaster. Our analysis reveals that point mutation and small indel rates vary significantly between the two different genetic backgrounds examined. We also find evidence that ∼2% of mutational events affect multiple closely spaced nucleotides. Unlike previous similar experiments, we were able to estimate genome-wide rates of large deletions and tandem duplications. These results suggest that, at least in inbred lines like those examined here, mutational pressures may result in net growth rather than contraction of the Drosophila genome. By comparing our mutation rate estimates to polymorphism data, we are able to estimate the fraction of new mutations that are eliminated by purifying selection. These results suggest that ∼99% of duplications and deletions are deleterious--making them 10 times more likely to be removed by selection than nonsynonymous mutations. Our results illuminate not only the rates of new small- and large-scale mutations, but also the selective forces that they encounter once they arise.

  12. Accuracy of High-Rate GPS for Seismology

    NASA Technical Reports Server (NTRS)

    Elosegui, P.; Davis, J. L.; Oberlander, D.; Baena, R.; Ekstrom, G.

    2006-01-01

    We built a device for translating a GPS antenna on a positioning table to simulate the ground motions caused by an earthquake. The earthquake simulator is accurate to better than 0.1 mm in position, and provides the "ground truth" displacements for assessing the technique of high-rate GPS. We found that the root-mean-square error of the 1-Hz GPS position estimates over the 15-min duration of the simulated seismic event was 2.5 mm, with approximately 96% of the observations in error by less than 5 mm, and is independent of GPS antenna motion. The error spectrum of the GPS estimates is approximately flicker noise, with a 50% decorrelation time for the position error of approx.1.6 s. We that, for the particular event simulated, the spectrum of dependent error in the GPS measurements. surface deformations exceeds the GPS error spectrum within a finite band. More studies are required to determine whether a generally optimal bandwidth exists for a target group of seismic events.

  13. [High vaccination rates among children of Amsterdam].

    PubMed

    van der Wal, M F; Diepenmaat, A C; Pauw-Plomp, H; van Weert-Waltman, M L

    2001-01-20

    To examine if in Amsterdam there are social or cultural groups of children with a relatively low vaccination coverage for diphtheria, pertussis, tetanus and poliomyelitis (DPTP) and mumps, measles and rubella (MMR). Descriptive cross-sectional study. In the Department of Child Health Care of the Municipal Health Service of Amsterdam all 83,217 children aged 2-12 years living in Amsterdam on the 1st of January 2000 were analysed for vaccination and sociodemographic data collected routinely by the Department of Child Health Care. The sociodemographic data concerned sex, year of birth, country of birth of the mother and child, name of the school and postal code of the home address. Schools were grouped by (religious) affiliation on the basis of the Amsterdam school guide 1999/2000. Based on postal codes children were classified by the neighbourhoods in which they were living. Neighbourhoods were grouped by socio-economic status based on data from the Central Bureau for Statistics. The overall vaccination rates of DPTP and MMR were 92.4% and 93.5% respectively. No important variation in vaccination coverage was identified between more and less affluent neighbourhoods. The uptake rate among foreign children was sometimes slightly higher and sometimes slightly lower compared with native children. Especially foreign children born abroad (Surinam, Antilles, Morocco, Turkey) were not fully vaccinated: 70.9% were fully immunized for DPTP, 79.5% for MMR. Children who visited anthroposophical schools were considerably less frequently fully immunized compared with children visiting other schools: for DPTP and MMR 81.0 and 59.9% respectively versus 94.4 en 95.3% for children attending general municipal schools. The vaccination coverage was high in children in Amsterdam. Further improvement of the vaccination uptake might be achieved by a more outreaching attitude to children born abroad, and by more intensely informing sceptical parents about the benefits and (supposed) dangers

  14. Higher rates of neuropsychiatric adverse events leading to dolutegravir discontinuation in women and older patients.

    PubMed

    Hoffmann, C; Welz, T; Sabranski, M; Kolb, M; Wolf, E; Stellbrink, H-J; Wyen, C

    2017-01-01

    Dolutegravir (DTG), a second-generation integrase strand transfer inhibitor (INSTI), is now among the most frequently used antiretroviral agents. However, recent reports have raised concerns about potential neurotoxicity. We performed a retrospective analysis of a cohort of HIV-infected patients who had initiated an INSTI in two large German out-patient clinics between 2007 and 2016. We compared discontinuation rates because of adverse events (AEs) within 2 years of starting treatment with dolutegravir, raltegravir or elvitegravir/cobicistat. We also evaluated factors associated with dolutegravir discontinuation. A total of 1950 INSTI-based therapies were initiated in 1704 patients eligible for analysis within the observation period. The estimated rates of any AE and of neuropsychiatric AEs leading to discontinuation within 12 months were 7.6% and 5.6%, respectively, for dolutegravir (n = 985), 7.6% and 0.7%, respectively, for elvitegravir (n = 287), and 3.3% and 1.9%, respectively, for raltegravir (n = 678). Neuropsychiatric AEs leading to dolutegravir discontinuation were observed more frequently in women [hazard ratio (HR) 2.64; 95% confidence interval (CI) 1.23-5.65; P = 0.012], in patients older than 60 years (HR: 2.86; 95% CI: 1.42-5.77; P = 0.003) and in human leucocyte antigen (HLA)-B*5701-negative patients who initiated abacavir at the same time (HR: 2.42; 95% CI: 1.38-4.24; P = 0.002). In this large cohort, the rate of discontinuation of dolutegravir because of neuropsychiatric adverse events was significantly higher than for other INSTIs, at almost 6% within 12 months. Despite the limitations of this retrospective study, the almost three-fold higher discontinuation rates observed amongst women and older patients underscore the need for further investigation, especially in patient populations usually underrepresented in clinical trials. © 2016 British HIV Association.

  15. Photocathodes for High Repetition Rate Light Sources

    SciTech Connect

    Ben-Zvi, Ilan

    2014-04-20

    This proposal brought together teams at Brookhaven National Laboratory (BNL), Lawrence Berkeley National Laboratory (LBNL) and Stony Brook University (SBU) to study photocathodes for high repetition rate light sources such as Free Electron Lasers (FEL) and Energy Recovery Linacs (ERL). Below details the Principal Investigators and contact information. Each PI submits separately for a budget through his corresponding institute. The work done under this grant comprises a comprehensive program on critical aspects of the production of the electron beams needed for future user facilities. Our program pioneered in situ and in operando diagnostics for alkali antimonide growth. The focus is on development of photocathodes for high repetition rate Free Electron Lasers (FELs) and Energy Recovery Linacs (ERLs), including testing SRF photoguns, both normal-­conducting and superconducting. Teams from BNL, LBNL and Stony Brook University (SBU) led this research, and coordinated their work over a range of topics. The work leveraged a robust infrastructure of existing facilities and the support was used for carrying out the research at these facilities. The program concentrated in three areas: a) Physics and chemistry of alkali-­antimonide cathodes (BNL – LBNL) b) Development and testing of a diamond amplifier for photocathodes (SBU -­ BNL) c) Tests of both cathodes in superconducting RF photoguns (SBU) and copper RF photoguns (LBNL) Our work made extensive use of synchrotron radiation materials science techniques, such as powder-­ and single-­crystal diffraction, x-­ray fluorescence, EXAFS and variable energy XPS. BNL and LBNL have many complementary facilities at the two light sources associated with these laboratories (NSLS and ALS, respectively); use of these will be a major thrust of our program and bring our understanding of these complex materials to a new level. In addition, CHESS at Cornell will be used to continue seamlessly throughout the NSLS dark period and

  16. Extreme Events: low and high total ozone over Arosa, Switzerland

    NASA Astrophysics Data System (ADS)

    Rieder, H. E.; Staehelin, J.; Maeder, J. A.; Ribatet, M.; Stübi, R.; Weihs, P.; Holawe, F.; Peter, T.; Davison, A. C.

    2009-04-01

    The frequency distribution of days with extreme low (termed ELOs) and high (termed EHOs) total ozone is analyzed for the world's longest total ozone record (Arosa, Switzerland - for details see Staehelin et al.,1998a,b), with new tools from extreme value theory (e.g. Coles, 2001; Ribatet, 2007). A heavy-tail focused approach is used through the fitting of the Generalized Pareto Distribution (GPD) to the Arosa time series. Asymptotic arguments (Pickands, 1975) justify the use of the GPD for modeling exceedances over a high (or below a low) enough threshold (Coles, 2001). The analysis shows that the GPD is appropriate for modeling the frequency distribution in total ozone above or below a mathematically well-defined threshold. While previous studies focused on so termed ozone mini-holes and mini-highs (e.g. Bojkov and Balis, 2001, Koch et al., 2005), this study is the first to present a mathematical description of extreme events in low and high total ozone for a northern mid-latitudes site (Rieder et al., 2009). The results show (a) an increase in days with extreme low (ELOs) and (b) a decrease in days with extreme high total ozone (EHOs) during the last decades, (c) that the general trend in total ozone is strongly determined by these extreme events and (d) that fitting the GPD is an appropriate method for the estimation of the frequency distribution of so-called ozone mini-holes. Furthermore, this concept allows one to separate the effect of Arctic ozone depletion from that of in situ mid-latitude ozone loss. As shown by this study, ELOs and EHOs have a strong influence on mean values in total ozone and the "extremes concept" could be further used also for validation of Chemistry-Climate-Models (CCMs) within the scientific community. References: Bojkov, R. D., and Balis, D.S.: Characteristics of episodes with extremely low ozone values in the northern middle latitudes 1975-2000, Ann. Geophys., 19, 797-807, 2001. Coles, S.: An Introduction to Statistical Modeling of

  17. Adverse Events of Extracorporeal Ultrasound-Guided High Intensity Focused Ultrasound Therapy

    PubMed Central

    Yu, Tinghe; Luo, Jun

    2011-01-01

    Background High-intensity focused ultrasound (HIFU) is considered to be an alternative to surgery. Extracorporeal ultrasound-guided HIFU (USgFU) has been clinically used to treat solid tumors. Preliminary trials in a small sample of a Western population suggested that this modality was safe. Most trials are performed in China thereby providing comprehensive data for understanding the safety profile. The aim of this study was to evaluate adverse events of USgFU therapy. Methods and Findings Clinical data were searched in 2 Chinese databases. Adverse events of USgFU were summarized and compared with those of magnetic resonance-guided HIFU (MRgFU; for uterine, bone or breast tumor) and transrectal ultrasound-guided HIFU (for prostate cancer or benign prostate hyperplasia). USgFU treatment was performed using 7 types of device. Side effects were evaluated in 13262 cases. There were fewer adverse events in benign lesions than in malignant lesions (11.81% vs. 21.65%, p<0.0001). Rates of adverse events greatly varied between the disease types (0–280%, p<0.0001) and between the applied HIFU devices in both malignant (10.58–44.38%, p<0.0001) and benign lesions (1.67–17.57%, p<0.0001). Chronological analysis did not demonstrate a decrease in the rate of adverse events. Based upon evaluable adverse events, incidences in USgFU were consistent with those in MRgFU or transrectal HIFU. Some side effects frequently occurred following transrectal HIFU were not reported in USgFU. Several events including intrahepatic metastasis, intraoperative high fever, and occlusions of the superior mesenteric artery should be of particular concern because they have not been previously noted. The types of adverse events suggested that they were ultrasonic lesions. Conclusion The frequency of adverse events depended on the location of the lesion and the type of HIFU device; however, side effects of USgFU were not yet understood. USgFU did not decrease the incidence of adverse events compared

  18. The relationship between the nuclei population and the cavitation event rate for cavitation on a Schiebe body

    SciTech Connect

    Liu, Z.; Brennen, C.E.

    1994-12-31

    Simultaneous measurements were made of the cavitation event rates on a Schiebe body and the nuclei number distributions in the oncoming stream in the Low Turbulence Water Tunnel at Caltech. Cavitation inception occurred at an average cavitation number of 0.57. Cavitation event rates increased dramatically as the cavitation number was decreased. It was also found that both the magnitude and the shape of the nuclei distribution changed substantially with the operating condition. These changes had very strong effect on the event rate and therefore on cavitation inception number based on a fixed event rate. At the same cavitation number, the changes in the event rate due to different free stream nuclei populations can be as much as a decade. The changes in the shape of the nuclei distribution occurred mostly in the nuclei size range above 15 {micro}m. The nuclei concentration tended to increase as cavitation number was decreased. And the cavitation event rate increased with he free stream nuclei concentration. The measured nuclei density distributions are used in an analytical model which attempts to correlate the even rate with the nuclei population. The predicted event rates are compared with those observed experimentally.

  19. Mapping from frame-driven to frame-free event-driven vision systems by low-rate rate coding and coincidence processing--application to feedforward ConvNets.

    PubMed

    Pérez-Carrasco, José Antonio; Zhao, Bo; Serrano, Carmen; Acha, Begoña; Serrano-Gotarredona, Teresa; Chen, Shouchun; Linares-Barranco, Bernabé

    2013-11-01

    Event-driven visual sensors have attracted interest from a number of different research communities. They provide visual information in quite a different way from conventional video systems consisting of sequences of still images rendered at a given "frame rate." Event-driven vision sensors take inspiration from biology. Each pixel sends out an event (spike) when it senses something meaningful is happening, without any notion of a frame. A special type of event-driven sensor is the so-called dynamic vision sensor (DVS) where each pixel computes relative changes of light or "temporal contrast." The sensor output consists of a continuous flow of pixel events that represent the moving objects in the scene. Pixel events become available with microsecond delays with respect to "reality." These events can be processed "as they flow" by a cascade of event (convolution) processors. As a result, input and output event flows are practically coincident in time, and objects can be recognized as soon as the sensor provides enough meaningful events. In this paper, we present a methodology for mapping from a properly trained neural network in a conventional frame-driven representation to an event-driven representation. The method is illustrated by studying event-driven convolutional neural networks (ConvNet) trained to recognize rotating human silhouettes or high speed poker card symbols. The event-driven ConvNet is fed with recordings obtained from a real DVS camera. The event-driven ConvNet is simulated with a dedicated event-driven simulator and consists of a number of event-driven processing modules, the characteristics of which are obtained from individually manufactured hardware modules.

  20. Single event upsets in semiconductor devices induced by highly ionising particles.

    PubMed

    Sannikov, A V

    2004-01-01

    A new model of single event upsets (SEUs), created in memory cells by heavy ions and high energy hadrons, has been developed. The model takes into account the spatial distribution of charge collection efficiency over the cell area not considered in previous approaches. Three-dimensional calculations made by the HADRON code have shown good agreement with experimental data for the energy dependence of proton SEU cross sections, sensitive depths and other SEU observables. The model is promising for prediction of SEU rates for memory chips exposed in space and in high-energy experiments as well as for the development of a high-energy neutron dosemeter based on the SEU effect.

  1. High resolution, high rate x-ray spectrometer

    DOEpatents

    Goulding, F.S.; Landis, D.A.

    1983-07-14

    It is an object of the invention to provide a pulse processing system for use with detected signals of a wide dynamic range which is capable of very high counting rates, with high throughput, with excellent energy resolution and a high signal-to-noise ratio. It is a further object to provide a pulse processing system wherein the fast channel resolving time is quite short and substantially independent of the energy of the detected signals. Another object is to provide a pulse processing system having a pile-up rejector circuit which will allow the maximum number of non-interfering pulses to be passed to the output. It is also an object of the invention to provide new methods for generating substantially symmetrically triangular pulses for use in both the main and fast channels of a pulse processing system.

  2. High rate PLD of diamond-like-carbon utilizing high repetition rate visible lasers

    SciTech Connect

    McLean, W. II; Fehring, E.J.; Dragon, E.P.; Warner, B.E.

    1994-09-15

    Pulsed Laser Deposition (PLD) has been shown to be an effective method for producing a wide variety of thin films of high-value-added materials. The high average powers and high pulse repetition frequencies of lasers under development at LLNL make it possible to scale-up PLD processes that have been demonstrated in small systems in a number of university, government, and private laboratories to industrially meaningful, economically feasible technologies. A copper vapor laser system at LLNL has been utilized to demonstrate high rate PLD of high quality diamond-like-carbon (DLC) from graphite targets. The deposition rates for PLD obtained with a 100 W laser were {approx} 2000 {mu}m{center_dot}cm{sup 2}/h, or roughly 100 times larger than those reported by chemical vapor deposition (CVD) or physical vapor deposition (PVD) methods. Good adhesion of thin (up to 2 pm) films has been achieved on a small number of substrates that include SiO{sub 2} and single crystal Si. Present results indicate that the best quality DLC films can be produced at optimum rates at power levels and wavelengths compatible with fiber optic delivery systems. If this is also true of other desirable coating systems, this PLD technology could become an extremely attractive industrial tool for high value added coatings.

  3. Metabolic Rates of ATP Transfer Through Creatine Kinase (CK Flux) Predict Clinical Heart Failure Events and Death

    PubMed Central

    Bottomley, Paul A.; Panjrath, Gurusher S.; Lai, Shenghan; Hirsch, Glenn A.; Wu, Katherine; Najjar, Samer S.; Steinberg, Angela; Gerstenblith, Gary; Weiss, Robert G.

    2015-01-01

    Morbidity and mortality from heart failure (HF) are high, and current risk stratification approaches for predicting HF progression are imperfect. Adenosine triphosphate (ATP) is required for normal cardiac contraction, and abnormalities in creatine kinase (CK) energy metabolism, the primary myocardial energy reserve reaction, have been observed in experimental and clinical HF. However, the prognostic value of abnormalities in ATP production rates through CK in human HF has not been investigated. Fifty-eight HF patients with nonischemic cardiomyopathy underwent 31P magnetic resonance spectroscopy (MRS) to quantify cardiac high-energy phosphates and the rate of ATP synthesis through CK (CK flux) and were prospectively followed for a median of 4.7 years. Multiple-event analysis (MEA) was performed for HF-related events including all-cause and cardiac death, HF hospitalization, cardiac transplantation, and ventricular-assist device placement. Among baseline demographic, clinical, and metabolic parameters, MEA identified four independent predictors of HF events: New York Heart Association (NYHA) class, left ventricular ejection fraction (LVEF), African-American race, and CK flux. Reduced myocardial CK flux was a significant predictor of HF outcomes, even after correction for NYHA class, LVEF, and race. For each increase in CK flux of 1 μmol g−1 s−1, risk of HF-related composite outcomes decreased by 32 to 39%. These findings suggest that reduced CK flux may be a potential HF treatment target. Newer imaging strategies, including noninvasive 31P MRS that detect altered ATP kinetics, could thus complement risk stratification in HF and add value in conditions involving other tissues with high energy demands, including skeletal muscle and brain. PMID:24337482

  4. Performance Evaluation of High-Rate GPS Seismometers

    NASA Astrophysics Data System (ADS)

    Kato, T.; Ebinuma, T.

    2011-12-01

    up to 10G acceleration to emulate high frequency and high acceleration earthquake motion. The simulation results showed that the amplitude was too small when the frequency was higher than 5Hz, and kinematic solutions were buried under the noise level. The jerk was also too high in such high frequency region, and no receiver was capable of maintaining signal lock. Many receivers lost signal under the acceleration higher than 4G. We also found that the accuracy of high-rate GPS observations was independent of sampling rate of the receivers, and the 50Hz sampling rate provides better resolution to the kinematic solutions. Our experiment suggested that, in the given environment and receiver sets, higher sampling interval was recommended to measure the ground motion in higher resolution. On the other hand, the dynamic characteristics of the signal tracking loop put a limit on the frequency and the acceleration of the antenna motion, and it would be quite difficult to capture the ground vibration with higher than 5Hz in frequency and 4G in acceleration. We will further continue our experiments to find the optimal configurations of the high-rate GPS receivers to monitor seismic events.

  5. Application of the IHI Global Trigger Tool in measuring the adverse event rate in a Turkish healthcare setting.

    PubMed

    Kurutkan, Mehmet Nurullah; Usta, Esra; Orhan, Fatih; Simsekler, M C Emre

    2015-01-01

    The goal of this study was to measure an adverse event rate and determine the potential usefulness of the Institute for Healthcare Improvement's Global Trigger Tool (GTT). Besides using the GTT to measure the adverse event rate, a comparison was also made with the internal Voluntary Reporting Notification System (VRNS) to identify and compare the strengths and weaknesses of the two approaches. Retrospective data were collected from reported patient safety incidents covering a one-year period at Duzce University Hospital, Turkey. Using a range of selection criteria, a total of 219 patient records were selected and then reviewed by a trained GTT team, to investigate the positive triggers in the content of the patient records. It was determined that adverse events per 1000 patient days totalled 80.72. Adverse events per 100 admissions were 29.39, and the rate of admissions with adverse events was 16.67%. The comparison between the GTT and the VRNS showed that the GTT is 19 times more sensitive than the VRNS in the adverse event evaluation process. This is the first published study of the rate of adverse events in a Turkish healthcare setting using the GTT. It was found that the GTT was applicable in this setting, yielding more accurate measurement of the adverse event rate. However, the content of the GTT should be adjusted regarding the standards and documentations used in the Turkish healthcare system to be more useful.

  6. PS foams at high pressure drop rates

    NASA Astrophysics Data System (ADS)

    Tammaro, Daniele; De Maio, Attilio; Carbone, Maria Giovanna Pastore; Di Maio, Ernesto; Iannace, Salvatore

    2014-05-01

    In this paper, we report data on PS foamed at 100 °C after CO2 saturation at 10 MPa in a new physical foaming batch that achieves pressure drop rates up to 120 MPa/s. Results show how average cell size of the foam nicely fit a linear behavior with the pressure drop rate in a double logarithmic plot. Furthermore, foam density initially decreases with the pressure drop rate, attaining a constant value at pressure drop rates higher than 40 MPa/s. Interestingly, furthermore, we observed that the shape of the pressure release curve has a large effect on the final foam morphology, as observed in tests in which the maximum pressure release rate was kept constant but the shape of the curve changed. These results allow for a fine tuning of the foam density and morphology for specific applications.

  7. Comparison of brand versus generic antiepileptic drug adverse event reporting rates in the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS).

    PubMed

    Rahman, Md Motiur; Alatawi, Yasser; Cheng, Ning; Qian, Jingjing; Plotkina, Annya V; Peissig, Peggy L; Berg, Richard L; Page, David; Hansen, Richard A

    2017-09-01

    Despite the cost saving role of generic anti-epileptic drugs (AEDs), debate exists as to whether generic substitution of branded AEDs may lead to therapeutic failure and increased toxicity. This study compared adverse event (AE) reporting rates for brand vs. authorized generic (AG) vs. generic AEDs. Since AGs are pharmaceutically identical to brand but perceived as generics, the generic vs. AG comparison minimized potential bias against generics. Events reported to the U.S. Food and Drug Administration Adverse Event Reporting System between January 2004 to March 2015 with lamotrigine, carbamazepine, and oxcarbazepine listed as primary or secondary suspect were classified as brand, generic, or AG based on the manufacturer. Disproportionality analyses using the reporting odds ratio (ROR) assessed the relative rate of reporting of labeled AEs compared to reporting these events with all other drugs. The Breslow-Day statistic compared RORs across brand, AG, and other generics using a Bonferroni-corrected P<0.01. A total of 27,150 events with lamotrigine, 13,950 events with carbamazepine, and 5077 events with oxcarbazepine were reported, with generics accounting for 27%, 41%, and 32% of reports, respectively. Although RORs for the majority of known AEs were different between brand and generics for all three drugs of interest (Breslow-Day P<0.001), RORs generally were similar for AG and generic comparisons. Generic lamotrigine and carbamazepine were more commonly involved in reports of suicide or suicidal ideation compared with the respective AGs based on a multiple comparison-adjusted P<0.01. Similar AED reporting rates were observed for the AG and generic comparisons for most outcomes and drugs, suggesting that brands and generics have similar reporting rates after accounting for generic perception biases. Disproportional suicide reporting was observed for generics compared with AGs and brand, although this finding needs further study. Copyright © 2017 Elsevier B

  8. High voltage high repetition rate pulse using Marx topology

    NASA Astrophysics Data System (ADS)

    Hakki, A.; Kashapov, N.

    2015-06-01

    The paper describes Marx topology using MOSFET transistors. Marx circuit with 10 stages has been done, to obtain pulses about 5.5KV amplitude, and the width of the pulses was about 30μsec with a high repetition rate (PPS > 100), Vdc = 535VDC is the input voltage for supplying the Marx circuit. Two Ferrite ring core transformers were used to control the MOSFET transistors of the Marx circuit (the first transformer to control the charging MOSFET transistors, the second transformer to control the discharging MOSFET transistors).

  9. Nitrogen Accumulation and Partitioning in High Arctic Tundra from Extreme Atmospheric N Deposition Events

    NASA Astrophysics Data System (ADS)

    Phoenix, G. K.; Osborn, A.; Blaud, A.; Press, M. C.; Choudhary, S.

    2013-12-01

    Arctic ecosystems are threatened by pollution from extreme atmospheric nitrogen (N) deposition events. These events occur from the long-range transport of reactive N from pollution sources at lower latitudes and can deposit up to 80% of the annual N deposition in just a few days. To date, the fate and impacts of these extreme pollutant events has remained unknown. Using a field simulation study, we undertook the first assessment of the fate of acutely deposited N on arctic tundra. Extreme N deposition events were simulated on field plots at Ny-Ålesund, Svalbard (79oN) at rates of 0, 0.04, 0.4 and 1.2 g N m-2 yr-1 applied as NH4NO3 solution over 4 days, with 15N tracers used in the second year to quantify the fate of the deposited N in the plant, soil, microbial and leachate pools. Separate applications of 15NO3- and 15NH4+ were also made to determine the importance of N form in the fate of N. Recovery of the 15N tracer at the end of the first growing season approached 100% of the 15N applied irrespective of treatment level, demonstrating the considerable capacity of High Arctic tundra to capture pollutant N from extreme deposition events. Most incorporation of the 15N was found in bryophytes, followed by the dominant vascular plant (Salix polaris) and the microbial biomass of the soil organic layer. Total recovery remained high in the second growing season (average of 90%), indicating highly conservative N retention. Between the two N forms, recovery of 15NO3- and 15NH4+ were equal in the non-vascular plants, whereas in the vascular plants (particularly Salix polaris) recovery of 15NO3- was four times higher than of 15NH4+. Overall, these findings show that High Arctic tundra has considerable capacity to capture and retain the pollutant N deposited in acute extreme deposition events. Given they can represent much of the annual N deposition, extreme deposition events may be more important than increased chronic N deposition as a pollution source. Furthermore

  10. Leading a highly visible hospital through a serious reportable event.

    PubMed

    Erickson, Jeanette Ives

    2012-03-01

    Most preventable adverse events result from systemic causes, not human error. The senior vice president for patient care/chief nurse at a leading hospital recounts the unnecessary death of a patient and the investigation that followed. Citing the critical importance of a "just culture," this case study offers a blueprint for managing a serious reportable event.

  11. HIgh Rate X-ray Fluorescence Detector

    SciTech Connect

    Grudberg, Peter Matthew

    2013-04-30

    The purpose of this project was to develop a compact, modular multi-channel x-ray detector with integrated electronics. This detector, based upon emerging silicon drift detector (SDD) technology, will be capable of high data rate operation superior to the current state of the art offered by high purity germanium (HPGe) detectors, without the need for liquid nitrogen. In addition, by integrating the processing electronics inside the detector housing, the detector performance will be much less affected by the typically noisy electrical environment of a synchrotron hutch, and will also be much more compact than current systems, which can include a detector involving a large LN2 dewar and multiple racks of electronics. The combined detector/processor system is designed to match or exceed the performance and features of currently available detector systems, at a lower cost and with more ease of use due to the small size of the detector. In addition, the detector system is designed to be modular, so a small system might just have one detector module, while a larger system can have many you can start with one detector module, and add more as needs grow and budget allows. The modular nature also serves to simplify repair. In large part, we were successful in achieving our goals. We did develop a very high performance, large area multi-channel SDD detector, packaged with all associated electronics, which is easy to use and requires minimal external support (a simple power supply module and a closed-loop water cooling system). However, we did fall short of some of our stated goals. We had intended to base the detector on modular, large-area detectors from Ketek GmbH in Munich, Germany; however, these were not available in a suitable time frame for this project, so we worked instead with pnDetector GmbH (also located in Munich). They were able to provide a front-end detector module with six 100 m^2 SDD detectors (two monolithic arrays of three elements each) along with

  12. Bipolar high-repetition-rate high-voltage nanosecond pulser

    SciTech Connect

    Tian Fuqiang; Wang Yi; Shi Hongsheng; Lei Qingquan

    2008-06-15

    The pulser designed is mainly used for producing corona plasma in waste water treatment system. Also its application in study of dielectric electrical properties will be discussed. The pulser consists of a variable dc power source for high-voltage supply, two graded capacitors for energy storage, and the rotating spark gap switch. The key part is the multielectrode rotating spark gap switch (MER-SGS), which can ensure wider range modulation of pulse repetition rate, longer pulse width, shorter pulse rise time, remarkable electrical field distortion, and greatly favors recovery of the gap insulation strength, insulation design, the life of the switch, etc. The voltage of the output pulses switched by the MER-SGS is in the order of 3-50 kV with pulse rise time of less than 10 ns and pulse repetition rate of 1-3 kHz. An energy of 1.25-125 J per pulse and an average power of up to 10-50 kW are attainable. The highest pulse repetition rate is determined by the driver motor revolution and the electrode number of MER-SGS. Even higher voltage and energy can be switched by adjusting the gas pressure or employing N{sub 2} as the insulation gas or enlarging the size of MER-SGS to guarantee enough insulation level.

  13. Bipolar high-repetition-rate high-voltage nanosecond pulser.

    PubMed

    Tian, Fuqiang; Wang, Yi; Shi, Hongsheng; Lei, Qingquan

    2008-06-01

    The pulser designed is mainly used for producing corona plasma in waste water treatment system. Also its application in study of dielectric electrical properties will be discussed. The pulser consists of a variable dc power source for high-voltage supply, two graded capacitors for energy storage, and the rotating spark gap switch. The key part is the multielectrode rotating spark gap switch (MER-SGS), which can ensure wider range modulation of pulse repetition rate, longer pulse width, shorter pulse rise time, remarkable electrical field distortion, and greatly favors recovery of the gap insulation strength, insulation design, the life of the switch, etc. The voltage of the output pulses switched by the MER-SGS is in the order of 3-50 kV with pulse rise time of less than 10 ns and pulse repetition rate of 1-3 kHz. An energy of 1.25-125 J per pulse and an average power of up to 10-50 kW are attainable. The highest pulse repetition rate is determined by the driver motor revolution and the electrode number of MER-SGS. Even higher voltage and energy can be switched by adjusting the gas pressure or employing N(2) as the insulation gas or enlarging the size of MER-SGS to guarantee enough insulation level.

  14. Estimating the ratio of multivariate recurrent event rates with application to a blood transfusion study.

    PubMed

    Ning, Jing; Rahbar, Mohammad H; Choi, Sangbum; Piao, Jin; Hong, Chuan; Del Junco, Deborah J; Rahbar, Elaheh; Fox, Erin E; Holcomb, John B; Wang, Mei-Cheng

    2015-07-09

    In comparative effectiveness studies of multicomponent, sequential interventions like blood product transfusion (plasma, platelets, red blood cells) for trauma and critical care patients, the timing and dynamics of treatment relative to the fragility of a patient's condition is often overlooked and underappreciated. While many hospitals have established massive transfusion protocols to ensure that physiologically optimal combinations of blood products are rapidly available, the period of time required to achieve a specified massive transfusion standard (e.g. a 1:1 or 1:2 ratio of plasma or platelets:red blood cells) has been ignored. To account for the time-varying characteristics of transfusions, we use semiparametric rate models for multivariate recurrent events to estimate blood product ratios. We use latent variables to account for multiple sources of informative censoring (early surgical or endovascular hemorrhage control procedures or death). The major advantage is that the distributions of latent variables and the dependence structure between the multivariate recurrent events and informative censoring need not be specified. Thus, our approach is robust to complex model assumptions. We establish asymptotic properties and evaluate finite sample performance through simulations, and apply the method to data from the PRospective Observational Multicenter Major Trauma Transfusion study.

  15. Search for Event Rate Modulation in XENON100 Electronic Recoil Data

    NASA Astrophysics Data System (ADS)

    Aprile, E.; Aalbers, J.; Agostini, F.; Alfonsi, M.; Anthony, M.; Arazi, L.; Arisaka, K.; Arneodo, F.; Balan, C.; Barrow, P.; Baudis, L.; Bauermeister, B.; Breur, P. A.; Brown, A.; Brown, E.; Bruenner, S.; Bruno, G.; Budnik, R.; Bütikofer, L.; Cardoso, J. M. R.; Cervantes, M.; Coderre, D.; Colijn, A. P.; Contreras, H.; Cussonneau, J. P.; Decowski, M. P.; de Perio, P.; di Giovanni, A.; Duchovni, E.; Fattori, S.; Ferella, A. D.; Fieguth, A.; Fulgione, W.; Gao, F.; Garbini, M.; Geis, C.; Goetzke, L. W.; Grignon, C.; Gross, E.; Hampel, W.; Hasterok, C.; Itay, R.; Kaether, F.; Kaminsky, B.; Kessler, G.; Kish, A.; Landsman, H.; Lang, R. F.; Le Calloch, M.; Lellouch, D.; Levinson, L.; Levy, C.; Lindemann, S.; Lindner, M.; Lopes, J. A. M.; Lyashenko, A.; Macmullin, S.; Marrodán Undagoitia, T.; Masbou, J.; Massoli, F. V.; Mayani, D.; Melgarejo Fernandez, A. J.; Meng, Y.; Messina, M.; Micheneau, K.; Miguez, B.; Molinario, A.; Murra, M.; Naganoma, J.; Ni, K.; Oberlack, U.; Orrigo, S. E. A.; Pakarha, P.; Persiani, R.; Piastra, F.; Pienaar, J.; Plante, G.; Priel, N.; Rauch, L.; Reichard, S.; Reuter, C.; Rizzo, A.; Rosendahl, S.; Dos Santos, J. M. F.; Sartorelli, G.; Schindler, S.; Schreiner, J.; Schumann, M.; Scotto Lavina, L.; Selvi, M.; Shagin, P.; Simgen, H.; Teymourian, A.; Thers, D.; Tiseni, A.; Trinchero, G.; Tunnell, C.; Wall, R.; Wang, H.; Weber, M.; Weinheimer, C.; Zhang, Y.; Xenon Collaboration

    2015-08-01

    We have searched for periodic variations of the electronic recoil event rate in the (2-6) keV energy range recorded between February 2011 and March 2012 with the XENON100 detector, adding up to 224.6 live days in total. Following a detailed study to establish the stability of the detector and its background contributions during this run, we performed an unbinned profile likelihood analysis to identify any periodicity up to 500 days. We find a global significance of less than 1 σ for all periods, suggesting no statistically significant modulation in the data. While the local significance for an annual modulation is 2.8 σ , the analysis of a multiple-scatter control sample and the phase of the modulation disfavor a dark matter interpretation. The DAMA/LIBRA annual modulation interpreted as a dark matter signature with axial-vector coupling of weakly interacting massive particles to electrons is excluded at 4.8 σ .

  16. Computational method to estimate Single Event Upset rates in an accelerator environment

    NASA Astrophysics Data System (ADS)

    Huhtinen, M.; Faccio, F.

    2000-08-01

    We present a new method to estimate Single Event Upsets (SEU) in a hadron accelerator environment, which is characterized by a complicated radiation spectrum. Our method is based on first principles, i.e. an explicit generation and transport of nuclear fragments and detailed accounting for energy loss by ionization. However, instead of simulating also the behaviour of the circuit, we use a Weibull fit to experimental heavy-ion SEU data in order to quantify the SEU sensitivity of the circuit. Thus, in principle, we do not need to know details about the circuit and our method is almost free of adjustable parameters - we only need a reasonable guess for the Sensitive Volume (SV) size. We show by a comparison with experimental data that our method predicts the SEU cross sections for protons rather accurately. We then indicate with an example how our method could be applied to predict SEU rates at the forthcoming LHC experiments.

  17. Evaluating system for SRAM-based FPGA single event upset rate

    NASA Astrophysics Data System (ADS)

    Wang, Yunlong; Bao, Bin

    2016-09-01

    This paper takes static random-access-memory (SRAM)-based field-programmable-gate-array (FPGA) as the research object. Attention is focused on the configuration memory of this kind of FPGA, and the research has been devoted to the contents of the configuration memory and the configuration circuit to manage its contents. The single event upset (SEU) happening in the configuration memory doesn't lead to a functional failure necessarily. The dynamic SEU is SEU which happens in the configuration memory and causes necessarily function failure. This paper introduces a test method of dynamic SUE rate for the SRAM-based FPGA by designing a FPGA with self-test function.

  18. GPU accelerated processing of astronomical high frame-rate videosequences

    NASA Astrophysics Data System (ADS)

    Vítek, Stanislav; Švihlík, Jan; Krasula, Lukáš; Fliegel, Karel; Páta, Petr

    2015-09-01

    Astronomical instruments located around the world are producing an incredibly large amount of possibly interesting scientific data. Astronomical research is expanding into large and highly sensitive telescopes. Total volume of data rates per night of operations also increases with the quality and resolution of state-of-the-art CCD/CMOS detectors. Since many of the ground-based astronomical experiments are placed in remote locations with limited access to the Internet, it is necessary to solve the problem of the data storage. It mostly means that current data acquistion, processing and analyses algorithm require review. Decision about importance of the data has to be taken in very short time. This work deals with GPU accelerated processing of high frame-rate astronomical video-sequences, mostly originating from experiment MAIA (Meteor Automatic Imager and Analyser), an instrument primarily focused to observing of faint meteoric events with a high time resolution. The instrument with price bellow 2000 euro consists of image intensifier and gigabite ethernet camera running at 61 fps. With resolution better than VGA the system produces up to 2TB of scientifically valuable video data per night. Main goal of the paper is not to optimize any GPU algorithm, but to propose and evaluate parallel GPU algorithms able to process huge amount of video-sequences in order to delete all uninteresting data.

  19. Single event effects in high-energy accelerators

    NASA Astrophysics Data System (ADS)

    García Alía, Rubén; Brugger, Markus; Danzeca, Salvatore; Cerutti, Francesco; de Carvalho Saraiva, Joao Pedro; Denz, Reiner; Ferrari, Alfredo; Foro, Lionel L.; Peronnard, Paul; Røed, Ketil; Secondo, Raffaello; Steckert, Jens; Thurel, Yves; Toccafondo, Iacocpo; Uznanski, Slawosz

    2017-03-01

    The radiation environment encountered at high-energy hadron accelerators strongly differs from the environment relevant for space applications. The mixed-field expected at modern accelerators is composed of charged and neutral hadrons (protons, pions, kaons and neutrons), photons, electrons, positrons and muons, ranging from very low (thermal) energies up to the TeV range. This complex field, which is extensively simulated by Monte Carlo codes (e.g. FLUKA) is due to beam losses in the experimental areas, distributed along the machine (e.g. collimation points) and deriving from the interaction with the residual gas inside the beam pipe. The resulting intensity, energy distribution and proportion of the different particles largely depends on the distance and angle with respect to the interaction point as well as the amount of installed shielding material. Electronics operating in the vicinity of the accelerator will therefore be subject to both cumulative damage from radiation (total ionizing dose, displacement damage) as well as single event effects which can seriously compromise the operation of the machine. This, combined with the extensive use of commercial-off-the-shelf components due to budget, performance and availability reasons, results in the need to carefully characterize the response of the devices and systems to representative radiation conditions.

  20. Cheetah: A high frame rate, high resolution SWIR image camera

    NASA Astrophysics Data System (ADS)

    Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

    2008-10-01

    A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

  1. 8.2 ky event associated with high precipitation in the eastern Caribbean

    NASA Astrophysics Data System (ADS)

    Winter, A.; Vieten, R.; Miller, T.; Mangini, A.; Scholz, D.

    2013-12-01

    We present data from speleothems collected in Venezuela and Puerto Rico showing that the eastern Caribbean was anomalously moist during the 8.2ka event. Evidence from high-resolution analyses of Greenland ice core (GISP2) shows that at the same time northern Europe and the north Atlantic were cooler by 3 - 6° C. The trigger for the 8.2ka event is thought to be pulsed meltwater discharges from a multi-event drainage of proglacial lakes associated with the decaying Laurentide Ice Sheet margin. The meltwater apparently slowed the thermohaline circulation decreasing warmth to northern Europe. At the same time moisture transfer to the northern latitudes may have slowed resulting in the observed lower latitude precipitation patterns. The eastern Caribbean seems to be especially sensitive to the changes in the strength of the Atlantic meridional overturning circulation (AMOC). Higher precipitation values may also have increased lowland flooding along the coastal areas of north eastern South America, already affected by early Holocene sea-level change, and are linked to social territory reshuffling which stimulated the earliest migrations into the Caribbean Archipelago shortly afterwards. Our age models based on precise MC-ICPMS 230Th/U-dating indicate that the eastern Caribbean stalagmites all grew at about the same rate of 15 cm through the 8.2 ka event, much faster than during any other growth period, except today when they are also growing at an accelerated rate.

  2. High data rate systems for the future

    NASA Technical Reports Server (NTRS)

    Chitwood, John

    1991-01-01

    Information systems in the next century will transfer data at rates that are much greater than those in use today. Satellite based communication systems will play an important role in networking users. Typical data rates; use of microwave, millimeter wave, or optical systems; millimeter wave communication technology; modulators/exciters; solid state power amplifiers; beam waveguide transmission systems; low noise receiver technology; optical communication technology; and the potential commercial applications of these technologies are discussed.

  3. Relating Spontaneously Reported Extrapyramidal Adverse Events to Movement Disorder Rating Scales.

    PubMed

    Widschwendter, Christian G; Karayal, Onur N; Kolluri, Sheela; Vanderburg, Douglas; Kemmler, Georg; Fleischhacker, W Wolfgang

    2015-06-26

    While antipsychotic-induced extrapyramidal symptoms (EPS) and akathisia remain important concerns in the treatment of patients with schizophrenia, the relationship between movement disorder rating scales and spontaneously reported EPS-related adverse events (EPS-AEs) remains unexplored. Data from four randomized, placebo- and haloperidol-controlled ziprasidone trials were analyzed to examine the relationship between spontaneously reported EPS-AEs with the Simpson Angus Scale (SAS) and Barnes Akathisia Rating Scale (BARS). Categorical summaries were created for each treatment group to show the frequencies of subjects with EPS-AEs in each of the SAS and BARS categories at weeks 1, 3, and 6, and agreement between ratings was quantified by means of weighted kappa (κ). In general, we found greater frequencies of EPS-AEs with increasing severity of the SAS and BARS scores. The EPS-AEs reported with a "none" SAS score ranged from 0 to 22.2%, with a "mild" SAS score from 3.3 to 29.0%, and with a "moderate" SAS score from 0 to 100%. No subjects in any treatment group reported "severe" SAS scores or corresponding EPS-AEs. Agreement between SAS scores and EPS-AEs was poor for ziprasidone and placebo (κ < 0.2) and only slightly better for haloperidol. The EPS-AEs reported with "non questionable" BARS scores ranged from 1.9 to 9.8%, with "mild moderate" BARS scores from 12.8 to 54.6%, and with "marked severe" scores from 0 to 100%. Agreement was modest for ziprasidone and placebo (κ < 0.4) and moderate for haloperidol (κ < 0.6). These findings may reflect either underreporting of AEs by investigators and subjects or erroneous rating scale evaluations. © The Author 2015. Published by Oxford University Press on behalf of CINP.

  4. Subjective rating of weak tactile stimuli is parametrically encoded in event-related potentials.

    PubMed

    Auksztulewicz, Ryszard; Blankenburg, Felix

    2013-07-17

    Neural signatures of somatosensory awareness have often been studied by examining EEG responses to hardly detectable stimuli. Previous reports consistently showed that event-related potentials (ERPs) measured over early somatosensory cortex diverge for detected and missed perithreshold stimuli at 80-100 ms after stimulus onset. So far, however, all previous studies have operationalized somatosensory awareness as binary stimulus detection. Here, we investigated whether ERP components attributed to neuronal activity in early somatosensory cortices would parametrically reflect subjective ratings of stimulus awareness. EEG (64 channel) was recorded in human participants (N = 20), with perithreshold electrical stimulation applied to the left median nerve. Participants indicated perceptibility on a continuous visual rating scale, and stimulation intensity was readjusted in each block to a perithreshold level. The aim of the analysis was to investigate which brain areas reflect the subsequent perceptual awareness ratings parametrically, and how early such parametric effects occur. Parametric ERP effects were found as early as 86 ms after stimulus onset. This parametric modulation of ERP amplitude was source localized to secondary somatosensory cortex, and attributed to feedforward processing between primary and secondary somatosensory cortex by means of dynamic causal modeling (DCM). Furthermore, later in the analysis window, the subjective rating of stimuli correlated with the amplitude of the N140 component and with a broadly distributed P300 component. By DCM modeling, these late effects were explained in terms of recurrent processing within the network of somatosensory and premotor cortices. Our results indicate that early neural activity in the somatosensory cortex can reflect the subjective quality of tactile perception.

  5. Generating High-Energy Events with Comets, Asteroids, and Planets

    NASA Astrophysics Data System (ADS)

    Di Stefano, Rosanne

    2015-08-01

    Many stellar remnants are likely to harbor systems of planetoids: comets, asteroids, and planets. Planetoids also travel freely through interstellar space. A combination of processes can therefore lead to tidal disruption events or collisions between planetoids and compact objects. These collisions can produce events that release a great deal of energy over a short time, and they are potentially detectable, even in external galaxies, by wide-field gamma-ray, X-ray, and optical surveys. We discuss the signatures and the possibility that these events could produce Type Ia supernovae.

  6. High Dose-Rate Versus Low Dose-Rate Brachytherapy for Lip Cancer

    SciTech Connect

    Ghadjar, Pirus; Bojaxhiu, Beat; Simcock, Mathew; Terribilini, Dario; Isaak, Bernhard; Gut, Philipp; Wolfensberger, Patrick; Broemme, Jens O.; Geretschlaeger, Andreas; Behrensmeier, Frank; Pica, Alessia; Aebersold, Daniel M.

    2012-07-15

    Purpose: To analyze the outcome after low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy for lip cancer. Methods and Materials: One hundred and three patients with newly diagnosed squamous cell carcinoma of the lip were treated between March 1985 and June 2009 either by HDR (n = 33) or LDR brachytherapy (n = 70). Sixty-eight patients received brachytherapy alone, and 35 received tumor excision followed by brachytherapy because of positive resection margins. Acute and late toxicity was assessed according to the Common Terminology Criteria for Adverse Events 3.0. Results: Median follow-up was 3.1 years (range, 0.3-23 years). Clinical and pathological variables did not differ significantly between groups. At 5 years, local recurrence-free survival, regional recurrence-free survival, and overall survival rates were 93%, 90%, and 77%. There was no significant difference for these endpoints when HDR was compared with LDR brachytherapy. Forty-two of 103 patients (41%) experienced acute Grade 2 and 57 of 103 patients (55%) experienced acute Grade 3 toxicity. Late Grade 1 toxicity was experienced by 34 of 103 patients (33%), and 5 of 103 patients (5%) experienced late Grade 2 toxicity; no Grade 3 late toxicity was observed. Acute and late toxicity rates were not significantly different between HDR and LDR brachytherapy. Conclusions: As treatment for lip cancer, HDR and LDR brachytherapy have comparable locoregional control and acute and late toxicity rates. HDR brachytherapy for lip cancer seems to be an effective treatment with acceptable toxicity.

  7. Mapping from Frame-Driven to Frame-Free Event-Driven Vision Systems by Low-Rate Rate-Coding and Coincidence Processing. Application to Feed Forward ConvNets.

    PubMed

    Perez-Carrasco, J A; Zhao, B; Serrano, C; Acha, B; Serrano-Gotarredona, T; Chen, S; Linares-Barranco, B

    2013-04-10

    Event-driven visual sensors have attracted interest from a number of different research communities. They provide visual information in quite a different way from conventional video systems consisting of sequences of still images rendered at “frame rate”. Event-driven vision sensors take inspiration from biology. A special type of Event-driven sensor is the so called Dynamic-Vision-Sensor (DVS) where each pixel computes relative changes of light, or “temporal contrast”. Pixel events become available with micro second delays with respect to “reality”. These events can be processed “as they flow” by a cascade of event (convolution) processors. As a result, input and output event flows are practically coincident, and objects can be recognized as soon as the sensor provides enough meaningful events. In this paper we present a methodology for mapping from a properly trained neural network in a conventional Frame-driven representation, to an Event-driven representation. The method is illustrated by studying Event-driven Convolutional Neural Networks (ConvNet) trained to recognize rotating human silhouettes or high speed poker card symbols. The Event-driven ConvNet is fed with recordings obtained from a real DVS camera. The Event-driven ConvNet is simulated with a dedicated Event-driven simulator, and consists of a number of Event-driven processing modules the characteristics of which are obtained from individually manufactured hardware modules.

  8. Observations of hydrotectonic stress/strain events at a basement high at the Nicoya outer rise

    NASA Astrophysics Data System (ADS)

    Tryon, M. D.; Brown, K. M.

    2005-12-01

    There is substantial and growing evidence from heat flow and coring investigations that the oceanic plate off Costa Rica is highly hydrologically active and that this activity is responsible for one of the most anomalously cold thermal environments encountered in the oceanic environment. Recent work by Fisher, et al. has identified limited regions above certain topographic highs with extremely high heat flows. Pore water profiles from cores above these thinly sedimented basement highs suggest upward flow on the order of ~1 cm/yr. These highs may be the principal regions of out-flow from the basement in this region and, thus, can potentially be used to constrain the general level of hydrologic activity. The nine Chemical and Aqueous Transport (CAT) meters we deployed at one of the highest heatflow sites provide a temporal record of both in-flow and out-flow of aqueous fluids at rates as low as 0.1 mm/yr. Our objective was to provide a direct measurement of long term flow rates to address the following questions: (1) What are the characteristic fluid fluxes at basement highs of the low heat flow region of the northern Costa Rican incoming plate, and (2) is this flow temporally variable? The results of the instrument deployments agree quite closely in general with the coring results in that the background rates are on the order of 1 cm/yr or less. There is, however, considerable detail in the temporal records which suggest small scale tectonic stress transients causing temporary increases in flow rate. While this is certainly not an area of major tectonic activity, the site is located at the top of the outer rise where one would expect bending-related stress and fault reactivation to occur. The CAT meters are capable of detecting minute strain events in the underlying sediments and therefore may be detecting small localized strain events. Two periods of increased flow lasting a few weeks each occur during the 5 month deployment and are indicated on all of the

  9. High-Resolution Structural Monitoring of Ionospheric Absorption Events

    DTIC Science & Technology

    2013-07-01

    Astronomy Observatory . The small circle is the instantaneous field-of-view of the CANOPUS riometer at Pinawa; this field-of-view is swept around the...precipitation events. Although limitations arising from initial data quality and radio frequency interference (RFI) have slowed implementation, the...precipitation events, radio interferometry, ionosphere 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a

  10. Event Rate for Extreme Mass Ratio Burst Signals in the Laser Interferometer Space Antenna Band

    NASA Astrophysics Data System (ADS)

    Rubbo, Louis J.; Holley-Bockelmann, Kelly; Finn, Lee Samuel

    2006-09-01

    Stellar mass compact objects in short-period (P<~103 s) orbits about a 104.5-107.5 Msolar massive black hole (MBH) are thought to be a significant continuous-wave source of gravitational radiation for the ESA/NASA Laser Interferometer Space Antenna (LISA) gravitational wave detector. These extreme mass ratio inspiral sources began in long-period, nearly parabolic orbits that have multiple close encounters with the MBH. The gravitational radiation emitted during the close encounters may be detectable by LISA as a gravitational wave burst if the characteristic passage timescale is less than 105 s. Scaling a static, spherical model to the size and mass of the Milky Way bulge, we estimate an event rate of ~15 yr-1 for such burst signals, detectable by LISA with signal-to-noise ratio greater than 5, originating in our Galaxy. When extended to include Virgo Cluster galaxies, our estimate increases to a gravitational wave burst rate of ~18 yr-1. We conclude that these extreme mass ratio burst sources may be a steady and significant source of gravitational radiation in the LISA data streams.

  11. The Risk of Cardiovascular Events After an Acute Coronary Event Remains High, Especially During the First Year, Despite Revascularization.

    PubMed

    Abu-Assi, Emad; López-López, Andrea; González-Salvado, Violeta; Redondo-Diéguez, Alfredo; Peña-Gil, Carlos; Bouzas-Cruz, Noelia; Raposeiras-Roubín, Sergio; Riziq-Yousef Abumuaileq, Rami; García-Acuña, José M; González-Juanatey, José R

    2016-01-01

    There is little information on the incidence and predictors of infarction, stroke, or cardiovascular death after acute coronary syndrome. We investigated these aspects and developed tools for predicting these events according to the time of their occurrence. A retrospective study was conducted of 4858 patients who survived an acute coronary event. We analyzed the incidence and predictors of acute myocardial infarction, stroke, or cardiovascular death during the first year (n=4858) vs successive years (n=4345 patients free of composite events during the first year). There were 329 events in the first year (cumulative incidence function: 7.3% person-years) and 616 in successive years (21.5% person-years; follow-up 4.9±2.4 years). The risk of events during the first year per tertile was 2.5% person-years in the low-risk tertile (< 3 points), 4.8% person-years in the intermediate-risk tertile (3-6 points), and 15.5% person-years in the high-risk tertile (> 6 points) (P<.001). The risk of events in the cohort that had a combined event in successive years increased from 10.7% person-years in the low-risk tertile (< 3 points) to 40.3% person-years in the high-risk tertile (> 6 points) (P<.001). The 2 scales showed the following predictive indexes: C statistic, 0.74 and 0.69, respectively; P (Hosmer-Lemeshow test)≥0.44 CONCLUSION: The risk of recurrence of cardiovascular events remains high after acute coronary syndrome. The level of risk can be easily quantified with acceptable predictive ability. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  12. Multiple channels of ADCs for high bit rate coherent optical OFDM with low sampling rate

    NASA Astrophysics Data System (ADS)

    Wen, He; Cheng, Lin; Zheng, Xiaoping; Zhang, Hanyi; Guo, Yili

    2009-11-01

    Multiple channels of ADCs for high bit rate CO-OFDM system is proposed by jointly processing outputs of all channels with a simple algorithm. The required sampling rate of ADCs is reduced lower than Nyquist rate.

  13. Monty Roberts’ Public Demonstrations: Preliminary Report on the Heart Rate and Heart Rate Variability of Horses Undergoing Training during Live Audience Events

    PubMed Central

    Loftus, Loni; Marks, Kelly; Jones-McVey, Rosie; Gonzales, Jose L.; Fowler, Veronica L.

    2016-01-01

    demonstrations within the United Kingdom. RR and HRV was measured in the stable before training and during training. The HRV variables standard deviation of the RR interval (SDRR), root mean square of successive RR differences (RMSSD), geometric means standard deviation 1 (SD1) and 2 (SD2), along with the low and high frequency ratio (LF/HF ratio) were calculated. The minimum, average and maximum RR intervals were significantly lower in training (indicative of an increase in heart rate as measured in beats-per-minute) than in the stable (p = 0.0006; p = 0.01; p = 0.03). SDRR, RMSSD, SD1, SD2 and the LF/HF ratio were all significantly lower in training than in the stable (p = 0.001; p = 0.049; p = 0.049; p = 0.001; p = 0.01). When comparing the HR and HRV of horses during Join-up® to overall training, there were no significant differences in any variable with the exception of maximum RR which was significantly lower (p = 0.007) during Join-up®, indicative of short increases in physical exertion (canter) associated with this training exercise. In conclusion, training of horses during public demonstrations is a low-moderate physiological, rather than psychological stressor for horses. The physiological stress responses observed within this study were comparable or less to those previously reported in the literature for horses being trained outside of public audience events. Furthermore, there is no evidence that the use of Join-up® alters HR and HRV in a way to suggest that this training method negatively affects the psychological welfare of horses. PMID:27618108

  14. Luminescence chronologies for sediments recording paleoseismic events and slip rate for the central Garlock fault, California, USA

    NASA Astrophysics Data System (ADS)

    Okubo, S. G.; Wolf, E.; Roder, B. J.; Rhodes, E. J.; McGill, S. F.; Dolan, J. F.; Mcauliffe, L. J.; Lawson, M. J.; Barrera, W. A.

    2012-12-01

    Luminescence dating has a significant role to play in providing chronological control for lacustrine and alluvial sediments that record both tectonic and climatic events. However, poor characteristics in some environments mean that the well-established method of OSL (optically stimulated luminescence) dating of quartz is not well-suited for the material available. In order to overcome this significant limitation, a range of methods based on the IRSL (infra-red stimulated luminescence) and ITL (isothermal thermoluminescence) of K-feldspar are currently under development. The site of El Paso Peaks, California has an established C-14 chronology spanning the last 7,000 years for a series of playa sediments comprising silts and fine sands, with occasional incursions of coarser sands and gravels from the alluvial fan that forms one side of the small ephemeral lake basin. Another barrier is formed by a shutter ridge of the left-lateral central Garlock fault, and this succession of sediments records at least six seismic events. Following collection of a suite of 24 luminescence samples distributed throughout the upper part of this succession, this site provides a rare opportunity to test different luminescence dating protocols in a rigorous fashion. At the site of Christmas Canyon West, a few miles further east, numerous small offsets of depositional and erosional alluvial fan features provide the opportunity to determine slip rates for a variety of timescales spanning the past couple of thousand years, besides forming a record of the timing of several discrete depositional episodes representing local high precipitation events. We review the challenges involved in developing a reliable luminescence chronology for sediment deposition in these contexts, and in relating this chronology to significant environmental events.

  15. Stroke and thromboembolic event rates in atrial fibrillation according to different guideline treatment thresholds: A nationwide cohort study

    PubMed Central

    Nielsen, Peter Brønnum; Larsen, Torben Bjerregaard; Skjøth, Flemming; Overvad, Thure Filskov; Lip, Gregory Y. H.

    2016-01-01

    Contemporary guidelines suggest anticoagulant treatment decisions in atrial fibrillation (AF) patients to be based on risk stratification for stroke. However, guidelines do not agree on the threshold for treatment initiation. We explored the variation in thromboembolic event rates in a non-anticoagulated AF population, according to different guideline threshold and methodological approaches. AF patients between 1998 and 2014 free from anticoagulant treatment were identified. Event rates for ischemic stroke and ischemic stroke/systemic embolism were explored. The overall ischemic stroke rate was 3.20 per 100 person-years (‘formal rate assessment’). For patients with a CHA2DS2-VASc score of 1 the ischemic stroke rate was 0.97 when using a ‘formal rate assessment’, 0.62 when using a ‘conditioning on the future’ approach, and 0.93 when using a ‘censoring approach’. Rates for thromboembolism for the ‘European treatment threshold’ (CHA2DS2-VASc score of 1, males only) ranged 1.17 to 1.53. Rates for the ‘U.S. treatment threshold’ (CHA2DS2-VASc of 2) ranged from 1.95 to 2.33. Thromboembolic event rates differed markedly in non-anticoagulated AF patients according to the conflicting European and U.S. guideline treatment thresholds. Second, the choice of methodological approach has implications, thus we recommend using the censoring approach for event rate estimation among AF patients not on treatment. PMID:27265586

  16. Rates and types of events reported to established incident reporting systems in two US hospitals

    PubMed Central

    Nuckols, Teryl K; Bell, Douglas S; Liu, Honghu; Paddock, Susan M; Hilborne, Lee H

    2007-01-01

    Background US hospitals have had voluntary incident reporting systems for many years, but the effectiveness of these systems is unknown. To facilitate substantial improvements in patient safety, the systems should capture incidents reflecting the spectrum of adverse events that are known to occur in hospitals. Objective To characterise the incidents from established voluntary hospital reporting systems. Design Observational study examining about 1000 reports of hospitalised patients at each of two hospitals. Patients and setting 16 575 randomly selected patients from an academic and a community hospital in the US in 2001. Main outcome measures Rates of incidents reported per hospitalised patient and characteristics of reported incidents. Results 9% of patients had at least one reported incident; 17 incidents were reported per 1000 patient‐days in hospital. Nurses filed 89% of reports, physicians 1.9% and other providers 8.9%. The most common types were medication incidents (29%), falls (14%), operative incidents (15%) and miscellaneous incidents (16%); 59% seemed preventable and preventability was not clear for 32%. Among the potentially preventable incidents, 43% involved nurses, 16% physicians and 19% other types of providers. Qualitative examination of reports indicated that very few involved prescribing errors or high‐risk procedures. Conclusions Hospital reporting systems receive many reports, but capture a spectrum of incidents that differs from the adverse events known to occur in hospitals, thereby substantially underdetecting physician incidents, particularly those involving operations, high‐risk procedures and prescribing errors. Increasing the reporting of physician incidents will be essential to enhance the effectiveness of hospital reporting systems; therefore, barriers to reporting such incidents must be minimised. PMID:17545340

  17. The Combustion of HMX. [burning rate at high pressures

    NASA Technical Reports Server (NTRS)

    Boggs, T. L.; Price, C. F.; Atwood, A. I.; Zurn, D. E.; Eisel, J. L.

    1980-01-01

    The burn rate of HMX was measured at high pressures (p more than 1000 psi). The self deflagration rate of HMX was determined from 1 atmosphere to 50,000 psi. The burning rate shows no significant slope breaks.

  18. The Combustion of HMX. [burning rate at high pressures

    NASA Technical Reports Server (NTRS)

    Boggs, T. L.; Price, C. F.; Atwood, A. I.; Zurn, D. E.; Eisel, J. L.

    1980-01-01

    The burn rate of HMX was measured at high pressures (p more than 1000 psi). The self deflagration rate of HMX was determined from 1 atmosphere to 50,000 psi. The burning rate shows no significant slope breaks.

  19. Single-Event Upsets Caused by High-Energy Protons

    NASA Technical Reports Server (NTRS)

    Price, W. E.; Nichols, D. K.; Smith, L. S.; Soli, G. A.

    1986-01-01

    Heavy secondary ions do not significantly alter device responses. Conclusion that external reaction products cause no significant alteration of single-event-upset response based on comparison of data obtained from both lidded and unlidded devices and for proton beams impinging at angles ranging from 0 degrees to 180 degrees with respect to chip face. Study also found single-event-upset cross section increases only modestly as proton energy increased to 590 MeV, characteristic of maximum energies expected in belts of trapped protons surrounding Earth and Jupiter.

  20. The effect of sporting events on emergency department attendance rates in a district general hospital in Northern Ireland.

    PubMed

    McGreevy, A; Millar, L; Murphy, B; Davison, G W; Brown, R; O'Donnell, M E

    2010-10-01

    Previous studies have reported a conflicting relationship between the effect of live and televised sporting events on attendance rates to emergency departments (ED). The objectives of this study were to investigate the relationship of major sporting events on emergency department attendance rates and to determine the potential effects of such events on service provision. A retrospective analysis of ED attendances to a district general hospital (DGH) and subsequent admissions over a 24-h period following live and televised sporting activities was performed over a 5-year period. Data were compiled from the hospital's emergency record books including the number of attendances, patient demographics, clinical complaint and outcome. Review patients were excluded. Analysis of sporting events was compiled for live local, regional and national events as well as world-wide televised sporting broadcasts. A total of 137,668 (80,445 men) patients attended from April 2002 to July 2007. Mean attendance rate per day was 80 patients (men = 47). Mean admission rate was 13.6 patients per day. Major sporting events during the study period included; Soccer: 4 FA Cup and 1 World Cup (WC) finals; Rugby: 47 Six Nations, 25 Six nations games involving Ireland, 1 WC final, 2 WC semi-finals, 2 WC quarter-finals and 4 WC games involving Ireland; and Gaelic Football [Gaelic Athletic Association (GAA)]: 5 All-Ireland finals, 11 semi-finals, 11 quarter-finals and 5 provincial finals. There was a significantly higher patient admission rate during the soccer FA Cup final, Rugby Six Nations and games involving Ireland and for GAA semi- and quarter-final games (p = 0.001-0.01). There was no difference identified in total attendance or non-admission rates for sporting events throughout the study period. Although there was no correlation identified between any of these sporting events and total emergency department attendances (r < 0.15, p > 0.07), multinomial logistic regression demonstrated that FA

  1. New high rate lead acid battery

    NASA Astrophysics Data System (ADS)

    Juergens, Tristan; Ruderman, Michael A.; Brodd, Ralph J.

    1994-05-01

    A new approach to the design of lead acid batteries has been developed based on the use of very thin lead foil current collectors. The basic cell construction and the performance characteristics for the new cell are described. Spiral wrap cells based on this electrode concept exhibit extremely high power output with excellent capacity maintenance. Additionally, these cells exhibit very flat voltage at all currents, and are capable of very rapid recharge. Applications for this high power technology cover a broad spectrum such as portable power tools, UPS systems, electrically heated catalytic converters, military pulse power applications, and electric and hybrid vehicles.

  2. The role of dose rate in radiation cancer risk: evaluating the effect of dose rate at the molecular, cellular and tissue levels using key events in critical pathways following exposure to low LET radiation.

    PubMed

    Brooks, Antone L; Hoel, David G; Preston, R Julian

    2016-08-01

    This review evaluates the role of dose rate on cell and molecular responses. It focuses on the influence of dose rate on key events in critical pathways in the development of cancer. This approach is similar to that used by the U.S. EPA and others to evaluate risk from chemicals. It provides a mechanistic method to account for the influence of the dose rate from low-LET radiation, especially in the low-dose region on cancer risk assessment. Molecular, cellular, and tissues changes are observed in many key events and change as a function of dose rate. The magnitude and direction of change can be used to help establish an appropriate dose rate effectiveness factor (DREF). Extensive data on key events suggest that exposure to low dose-rates are less effective in producing changes than high dose rates. Most of these data at the molecular and cellular level support a large (2-30) DREF. In addition, some evidence suggests that doses delivered at a low dose rate decrease damage to levels below that observed in the controls. However, there are some data human and mechanistic data that support a dose-rate effectiveness factor of 1. In summary, a review of the available molecular, cellular and tissue data indicates that not only is dose rate an important variable in understanding radiation risk but it also supports the selection of a DREF greater than one as currently recommended by ICRP ( 2007 ) and BEIR VII (NRC/NAS 2006 ).

  3. Ultra High Bit-Rate Communications for Future Space Missions

    NASA Astrophysics Data System (ADS)

    Dudelzak, A. E.; Jha, V. K.; Pasmanik, G. A.

    2002-01-01

    systems. Needs of applications such as real-time surveillance of dynamic situations on the ground or in near space, video data on event scenes in search and rescue, real-time video communications with spacecraft, etc. can only be provided with signal carrying frequencies in the optical wavelength range. Today's optical free-space communication technologies promise to reach the performance quality of the ground optical fiber networks. Recent developments based on using the optical phase conjugation and photo- dynamic holography phenomena allow transmission of high data volumes (such as dynamic imagery and real-time video communications) between moving communication terminals. surveillance and communications with spacecraft (both within and beyond solar system) using non-linear optical systems. The advantage of the discussed concept is that it may not require lasers (as sources of the signal-carrying electromagnetic waves) on both communicating terminals. A combination of a limited number of ground-based laser stations with compact, light-weight passive non-linear optical systems on high and low orbits or on long-range spacecraft provides for reliable, ultra-high rate, economic systems for voice, data and video communications as well as real-time observations of Earth, near and deep space. presented.

  4. UKIRT Microlensing Surveys as a Pathfinder for WFIRST: The Detection of Five Highly Extinguished Low-∣b∣ Events

    NASA Astrophysics Data System (ADS)

    Shvartzvald, Y.; Bryden, G.; Gould, A.; Henderson, C. B.; Howell, S. B.; Beichman, C.

    2017-02-01

    Optical microlensing surveys are restricted from detecting events near the Galactic plane and center, where the event rate is thought to be the highest due to the high optical extinction of these fields. In the near-infrared (NIR), however, the lower extinction leads to a corresponding increase in event detections and is a primary driver for the wavelength coverage of the WFIRST microlensing survey. During the 2015 and 2016 bulge observing seasons, we conducted NIR microlensing surveys with UKIRT in conjunction with and in support of the Spitzer and Kepler microlensing campaigns. Here, we report on five highly extinguished ({A}H=0.81{--}1.97), low-Galactic latitude (-0.98≤slant b≤slant -0.36) microlensing events discovered from our 2016 survey. Four of them were monitored with an hourly cadence by optical surveys but were not reported as discoveries, likely due to the high extinction. Our UKIRT surveys and suggested future NIR surveys enable the first measurement of the microlensing event rate in the NIR. This wavelength regime overlaps with the bandpass of the filter in which the WFIRST microlensing survey will conduct its highest-cadence observations, making this event rate derivation critically important for optimizing its yield.

  5. High Count Rate Electron Probe Microanalysis.

    PubMed

    Geller, Joseph D; Herrington, Charles

    2002-01-01

    Reducing the measurement uncertainty of quantitative analyses made using electron probe microanalyzers (EPMA) requires a careful study of the individual uncertainties from each definable step of the measurement. Those steps include measuring the incident electron beam current and voltage, knowing the angle between the electron beam and the sample (takeoff angle), collecting the emitted x rays from the sample, comparing the emitted x-ray flux to known standards (to determine the k-ratio) and transformation of the k-ratio to concentration using algorithms which includes, as a minimum, the atomic number, absorption, and fluorescence corrections. This paper discusses the collection and counting of the emitted x rays, which are diffracted into the gas flow or sealed proportional x-ray detectors. The representation of the uncertainty in the number of collected x rays collected reduces as the number of counts increase. The uncertainty of the collected signal is fully described by Poisson statistics. Increasing the number of x rays collected involves either counting longer or at a higher counting rate. Counting longer means the analysis time increases and may become excessive to get to the desired uncertainty. Instrument drift also becomes an issue. Counting at higher rates has its limitations, which are a function of the detector physics and the detecting electronics. Since the beginning of EPMA analysis, analog electronics have been used to amplify and discriminate the x-ray induced ionizations within the proportional counter. This paper will discuss the use of digital electronics for this purpose. These electronics are similar to that used for energy dispersive analysis of x rays with either Si(Li) or Ge(Li) detectors except that the shaping time constants are much smaller.

  6. High neutral transverse energy events at the CERN ISR

    SciTech Connect

    Cox, P. T.

    1983-01-01

    The CERN-Oxford-Rockefeller (COR) collaboration has obtained neutral transverse energy, E/sub T//sup 0/, spectra in pp collisions at ..sqrt..s = 30.5, 45.0, and 62.3 GeV. Evidence is presented for the increasing dominance of 2-jet events as E/sub T//sup 0/ increases.

  7. A flexible high-rate USB2 data acquisition system for PET and SPECT imaging

    SciTech Connect

    J. Proffitt, W. Hammond, S. Majewski, V. Popov, R.R. Raylman, A.G. Weisenberger, R. Wojcik

    2006-02-01

    A new flexible data acquisition system has been developed to instrument gamma-ray imaging detectors designed by the Jefferson Lab Detector and Imaging Group. Hardware consists of 16-channel data acquisition modules installed on USB2 carrier boards. Carriers have been designed to accept one, two, and four modules. Application trigger rate and channel density determines the number of acquisition boards and readout computers used. Each channel has an independent trigger, gated integrator and a 2.5 MHz 12-bit ADC. Each module has an FPGA for analog control and signal processing. Processing includes a 5 ns 40-bit trigger time stamp and programmable triggering, gating, ADC timing, offset and gain correction, charge and pulse-width discrimination, sparsification, event counting, and event assembly. The carrier manages global triggering and transfers module data to a USB buffer. High-granularity time-stamped triggering is suitable for modular detectors. Time stamped events permit dynamic studies, complex offline event assembly, and high-rate distributed data acquisition. A sustained USB data rate of 20 Mbytes/s, a sustained trigger rate of 300 kHz for 32 channels, and a peak trigger rate of 2.5 MHz to FIFO memory were achieved. Different trigger, gating, processing, and event assembly techniques were explored. Target applications include >100 kHz coincidence rate PET detectors, dynamic SPECT detectors, miniature and portable gamma detectors for small-animal and clinical use.

  8. Transition event statistics in genetics and disordered kinetics. Theoretical approaches for extracting rate distributions from experimental data.

    PubMed

    Vlad, Marcel O; Oefner, Peter; Ross, John

    2006-09-28

    We study the analogies between the theory of rate processes in disordered systems and the overdispersed molecular clocks in evolutionary biology. A biological "molecular clock" expresses the statistics of the number of amino acid or nucleotide substitutions during evolution. Random variations of the evolution rates lead to statistical (overdispersed) molecular clocks which are described by random point processes with random substitution rates. We find that the models for overdispersed molecular clocks are equivalent to those of the random-rate or random channel models used in disordered kinetics. The number of transport (reaction) events in disordered kinetics plays the same role as the number of substitution events in molecular biology. We study the connections between the (observed) statistics of the transition events and the statistics of random rate coefficients and random channels; a unified approach is developed which is valid both in molecular biology and in disordered kinetics. We develop methods for extracting statistical information about the variations of rate coefficients from experimental or observed data regarding the fluctuations of the numbers of substitution, reaction, or transport events. For systems with static disorder, the observed statistics of the number of reaction events, expressed in terms of probabilities at a given time or by the cumulants of the number of transition events at a given time, contains the information necessary for evaluating the cumulants or the probability density of the rate coefficients or the density of states for random channel kinetics. For dynamic disorder this is not possible; further information about multitime probability distributions of the reaction events is needed.

  9. Seismic velocity change and slip rate during the 2006 Guerrero (Mexico) slow slip event

    NASA Astrophysics Data System (ADS)

    Rivet, Diane; Radiguet, Mathilde; Campillo, Michel; Cotton, Fabrice; Shapiro, Nikolai; Krishna Singh, Shri; Kostoglodov, Vladimir

    2010-05-01

    We measure temporal change of the seismic velocity in the crust below the Guerrero region during the 2006 slow sleep event (SSE). We use repeated cross-correlations of ambient seismic noise recorded at 26 broad-band stations of the MesoAmerica Seismic Experiment (MASE). The cross-correlations are computed over 90 days with a moving window of 10 days from January 2005 to July 2007. To insure measurements independent of noise source variations, we only take into account the travel time change within the coda. For period of 8 to 20s, we observe a decrease in velocity starting in April 2006 with a maximum change of -0.3% of the initial velocity in June 2006. At these periods, the Rayleigh waves are sensitive to velocity changes down to the lower crust. In the other hand, we compute the deformation rate below the MASE array from a slip propagation model of the SSE observed by means of the displacement time-series of 15 continuous GPS stations. Slip initiates in the western part of the Guerrero Gap and propagates southeastward. The propagation velocity is of the order of 1 km/day. We then compare the seismic velocity change measured from continuous seismological data with the deformation rate inferred from geodetic measurements below the MASE array. We obtain a good agreement between the time of maximal seismic velocity change (July 2006) and the time of maximum deformation associated with the SSE (July to August 2006). This result shows that the long-term velocity change associated with the SSE can be detected using continuous seismic recordings. Since the SSE does not emit seismic waves, which interact with the superficial layers, the result indicates that the velocity change is due to deformation at depth.

  10. Heart rate regulation during cycle-ergometer exercise via event-driven biofeedback.

    PubMed

    Argha, Ahmadreza; Su, Steven W; Celler, Branko G

    2017-03-01

    This paper is devoted to the problem of regulating the heart rate response along a predetermined reference profile, for cycle-ergometer exercises designed for training or cardio-respiratory rehabilitation. The controller designed in this study is a non-conventional, non-model-based, proportional, integral and derivative (PID) controller. The PID controller commands can be transmitted as biofeedback auditory commands, which can be heard and interpreted by the exercising subject to increase or reduce exercise intensity. However, in such a case, for the purposes of effectively communicating to the exercising subject a change in the required exercise intensity, the timing of this feedback signal relative to the position of the pedals becomes critical. A feedback signal delivered when the pedals are not in a suitable position to efficiently exert force may be ineffective and this may, in turn, lead to the cognitive disengagement of the user from the feedback controller. This note examines a novel form of control system which has been expressly designed for this project. The system is called an "actuator-based event-driven control system". The proposed control system was experimentally verified using 24 healthy male subjects who were randomly divided into two separate groups, along with cross-validation scheme. A statistical analysis was employed to test the generalisation of the PID tunes, derived based on the average transfer functions of the two groups, and it revealed that there were no significant differences between the mean values of root mean square of the tracking error of two groups (3.9 vs. 3.7 bpm, [Formula: see text]). Furthermore, the results of a second statistical hypothesis test showed that the proposed PID controller with novel synchronised biofeedback mechanism has better performance compared to a conventional PID controller with a fixed-rate biofeedback mechanism (Group 1: 3.9 vs. 5.0 bpm, Group 2: 3.7 vs. 4.4 bpm, [Formula: see text]).

  11. Errors in administrative-reported ventilator-associated pneumonia rates: are never events really so?

    PubMed

    Thomas, Bradley W; Maxwell, Robert A; Dart, Benjamin W; Hartmann, Elizabeth H; Bates, Dustin L; Mejia, Vicente A; Smith, Philip W; Barker, Donald E

    2011-08-01

    Ventilator-associated pneumonia (VAP) is a common problem in an intensive care unit (ICU), although the incidence is not well established. This study aims to compare the VAP incidence as determined by the treating surgical intensivist with that detected by the hospital Infection Control Service (ICS). Trauma and surgical patients admitted to the surgical critical care service were prospectively evaluated for VAP during a 5-month time period. Collected data included the surgical intensivist's clinical VAP (SIS-VAP) assessment using Centers for Disease Control and Prevention (CDC) VAP criteria. As part of the hospital's VAP surveillance program, these patients' medical records were also reviewed by the ICS for VAP (ICS-VAP) using the same CDC VAP criteria. All patients suspected of having VAP underwent bronchioalveolar lavage (BAL). The SIS-VAP and ICS-VAP were then compared with BAL-VAP. Three hundred twenty-nine patients were admitted to the ICU during the study period. One hundred thirty-three were intubated longer than 48 hours and comprised our study population. Sixty-two patients underwent BAL evaluation for the presence of VAP on 89 occasions. SIS-VAP was diagnosed in 38 (28.5%) patients. ICS-VAP was identified in 11 (8.3%) patients (P < 0.001). The incidence of VAP by BAL criteria was 23.3 per cent. When compared with BAL, SIS-VAP had 61.3 per cent sensitivity and ICS-VAP had 29 per cent sensitivity. VAP rates reported by hospital administrative sources are significantly less accurate than physician-reported rates and dramatically underestimate the incidence of VAP. Proclaiming VAP as a never event for critically ill for surgical and trauma patients appears to be a fallacy.

  12. Low-event-rate meta-analyses of clinical trials: implementing good practices.

    PubMed

    Shuster, Jonathan J; Walker, Michael A

    2016-06-30

    Meta-analysis of clinical trials is a methodology to summarize information from a collection of trials about an intervention, in order to make informed inferences about that intervention. Random effects allow the target population outcomes to vary among trials. Since meta-analysis is often an important element in helping shape public health policy, society depends on biostatisticians to help ensure that the methodology is sound. Yet when meta-analysis involves randomized binomial trials with low event rates, the overwhelming majority of publications use methods currently not intended for such data. This statistical practice issue must be addressed. Proper methods exist, but they are rarely applied. This tutorial is devoted to estimating a well-defined overall relative risk, via a patient-weighted random-effects method. We show what goes wrong with methods based on 'inverse-variance' weights, which are almost universally used. To illustrate similarities and differences, we contrast our methods, inverse-variance methods, and the published results (usually inverse-variance) for 18 meta-analyses from 13 Journal of the American Medical Association articles. We also consider the 2007 case of rosiglitazone (Avandia), where important public health issues were at stake, involving patient cardiovascular risk. The most widely used method would have reached a different conclusion. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

  13. Event Rate for LISA Gravitational Wave Signals from Black Hole-Massive Black Hole Coalescences

    NASA Technical Reports Server (NTRS)

    Bender, Peter L.; Salamon, Michael H. (Technical Monitor)

    2002-01-01

    Earlier work under a previous grant had been mainly on investigating the event rate for coalescences of white dwarfs or neutron stars with massive black holes (MBHs) in galactic nuclei. Under the new grant, two studies were undertaken. One was an approximate extension of the earlier study to stellar mass black holes as the lighter object, with masses in the range of roughly 3 to 20 M_sun, rather than about 1 M_sun. The other was an improved estimate of the confusion noise due to galactic binaries against which the signals from BH-MDH coalescences would have to be detected. In the earlier work, the mass of the white dwarfs (WDs) and neutron stars (NSs) was assumed to be about the same as that of the unevolved stars in the density cusp around the galactic center MBH. However, with the BH mass being substantially larger, the sinking down of BHs toward the center (mass segregation) became important and was included in the model. A single representative mass of 7 M_sun was used.

  14. "Owning" the personal past: Adolescents' and adults' autobiographical narratives and ratings of memories of recent and distant events.

    PubMed

    Bauer, Patricia J; Hättenschwiler, Nicole; Larkina, Marina

    2016-01-01

    Adults and adolescents are characterised as having different perspectives on their personal or autobiographical memories. Adults are recognised as having vivid recollections of past events and as appreciating the meaning and significance of their autobiographical memories. In development, these qualities are noted as absent as late as adolescence. To evaluate the assumption of developmental differences, we directly compared autobiographical memories of adults and adolescents drawn from each of several periods in the past, using measures of narrative quality (coded independently) and participants' own subjective ratings of their memories. Adults' narratives of events from the previous year and for the "most significant" event of their lives were coded as more thematically coherent relative to those of adolescents'; the groups did not differ on thematic coherence of narratives of early-life events (ages 1-5 and 6-10 years). The ratings that adults and adolescents provided of their autobiographical memories were similar overall; differences were more apparent for early-life events than for more recent events and indicated stronger mnemonic experiences among adolescents than adults. The pattern of findings suggests that whereas adults have more sophisticated narrative tools for describing the significance of events and their relation to the corpus of autobiographical memories, adolescents as well as adults have vivid recollective experiences as well as personal and subjective perspective on the events of their lives and their memories thereof.

  15. High pressure, high strain rate material strength studies

    NASA Astrophysics Data System (ADS)

    Remington, B. A.; Arsenlis, A.; Barton, N.; Belof, J.; Cavallo, R.; Maddox, B.; Park, H.-S.; Prisbrey, S.; Rudd, R.; Comley, A.; Meyers, M.; Wark, J.

    2011-10-01

    Constitutive models for material strength are currently being tested at high pressures by comparing 2D simulations with experiments measuring the Rayleigh-Taylor (RT) instability evolution in solid-state samples of vanadium (V), tantalum (Ta), and iron (Fe). The multiscale strength models being tested combine molecular dynamics, dislocation dynamics, and continuum simulations. Our analysis for the V experiments suggests that the material deformation at these conditions falls into the phonon drag regime, whereas for Ta, the deformation resides mainly in the thermal activation regime. Recent Fe-RT experiments suggest perturbation growth about the alpha-epsilon (bcc-hcp) phase transition threshold has been observed. Using the LLNL multiscale models, we decompose the strength as a function of strain rate into its dominant components of thermal activation, phonon drag, and work hardening. We have also developed a dynamic diffraction diagnostic technique to measure strength directly from shock compressed single crystal samples. Finally, recovery experiments allow a comparison of residual dislocation density with predictions from the multiscale model. This work performed under the auspices of the U.S. DoE by LLNL Security, LLC under Contract DE-AC52-07NA27344.

  16. High performance interconnection between high data rate networks

    NASA Technical Reports Server (NTRS)

    Foudriat, E. C.; Maly, K.; Overstreet, C. M.; Zhang, L.; Sun, W.

    1992-01-01

    The bridge/gateway system needed to interconnect a wide range of computer networks to support a wide range of user quality-of-service requirements is discussed. The bridge/gateway must handle a wide range of message types including synchronous and asynchronous traffic, large, bursty messages, short, self-contained messages, time critical messages, etc. It is shown that messages can be classified into three basic classes, synchronous and large and small asynchronous messages. The first two require call setup so that packet identification, buffer handling, etc. can be supported in the bridge/gateway. Identification enables resequences in packet size. The third class is for messages which do not require call setup. Resequencing hardware based to handle two types of resequencing problems is presented. The first is for a virtual parallel circuit which can scramble channel bytes. The second system is effective in handling both synchronous and asynchronous traffic between networks with highly differing packet sizes and data rates. The two other major needs for the bridge/gateway are congestion and error control. A dynamic, lossless congestion control scheme which can easily support effective error correction is presented. Results indicate that the congestion control scheme provides close to optimal capacity under congested conditions. Under conditions where error may develop due to intervening networks which are not lossless, intermediate error recovery and correction takes 1/3 less time than equivalent end-to-end error correction under similar conditions.

  17. High dose rate brachytherapy source measurement intercomparison.

    PubMed

    Poder, Joel; Smith, Ryan L; Shelton, Nikki; Whitaker, May; Butler, Duncan; Haworth, Annette

    2017-06-01

    This work presents a comparison of air kerma rate (AKR) measurements performed by multiple radiotherapy centres for a single HDR (192)Ir source. Two separate groups (consisting of 15 centres) performed AKR measurements at one of two host centres in Australia. Each group travelled to one of the host centres and measured the AKR of a single (192)Ir source using their own equipment and local protocols. Results were compared to the (192)Ir source calibration certificate provided by the manufacturer by means of a ratio of measured to certified AKR. The comparisons showed remarkably consistent results with the maximum deviation in measurement from the decay-corrected source certificate value being 1.1%. The maximum percentage difference between any two measurements was less than 2%. The comparisons demonstrated the consistency of well-chambers used for (192)Ir AKR measurements in Australia, despite the lack of a local calibration service, and served as a valuable focal point for the exchange of ideas and dosimetry methods.

  18. High Strain Rate Response of an Elastomer

    NASA Astrophysics Data System (ADS)

    Jiao, Tong; Clifton, Rodney J.; Grunschel, Stephen E.

    2006-07-01

    Pressure-shear plate impact experiments are used to study the nonlinear dynamic response of an elastomer at shearing rates of 105 - 106 s-1. Samples with thicknesses in the range 100 μm - 400 μm are cast between two hard steel plates. Because of the comparatively low impedance of the elastomer, longitudinal waves reverberating through the thickness of the sample — and recorded with a laser interferometer — are used to determine the isentrope of the material under uniaxial strain compression. Once the sample is fully compressed a shear wave arrives and imposes a simple shearing deformation. From the transverse velocity, measured interferometrically at the rear surface of the sandwich target, the shear stress and the transverse velocity at the rear surface of the sample are determined. These measurements provide an indication of the shearing resistance of the material under pressure. When the longitudinal unloading wave arrives from the rear surface of the target, these same measurements provide an indication of the shearing resistance of the material at zero pressure. Because the sample adheres to the bounding plates the reflection of unloading waves from both the rear surface of the flyer and the rear surface of the target allows the sample to be strained in uniaxial extension. Thus, from a single experiment, one obtains the response of the elastomer in uniaxial strain compression, simple shear and uniaxial strain extension.

  19. A comparison of coronary heart disease event rates among urban Australian Aboriginal people and a matched non-Aboriginal population.

    PubMed

    Bradshaw, Pamela J; Alfonso, Helman S; Finn, Judith; Owen, Julie; Thompson, Peter L

    2011-04-01

    Age-specific death from cardiovascular disease among Australian Aboriginals is estimated to be four to seven times that of general population, and the major cause of premature death. There is little reliable information on the incidence of coronary heart disease (CHD). This study compares CHD event rates in urban-dwelling Aboriginal people and the general population. The Perth Aboriginal Atherosclerosis Risk Study (PAARS) cohort was assessed at baseline (1998/1999) and 913 participants followed-up to 2006. A comparison group of age-matched, sex-matched and postcode-matched non-Aboriginals (n=3582) were selected from the Perth, Western Australia, Electoral Roll. Electronic record linkage captured prior CHD and first CHD events in both groups. The rates of first CHD events (hospital admission or CHD death) per 1000 person years (PY) and incidence rate ratios (IRR) were calculated. The event rate for the PAARS population was 14.9 per 1000 PY (95% CI 12.3 to 18.2) versus 2.4 (1.9 to 3.1) for the general population. The IRR was 6.1 (4.5 to 8.4). For Aboriginal men the rate was 15.0 (11.2 to 20.0) versus 3.8 (2.5 to 5.0) per 1000 PY, with age-specific rates being two to five times that of non-Aboriginals. Incidence for Aboriginal women was 15.0 (11.5 to 19.5) versus 1.4 (0.9 to 2.1) with age-specific rates being 8-25 times that of non-Aboriginals. Age and sex-specific CHD event rates in urban Aboriginals far exceeded that of a matched general population. Events occurred at a much younger age among the Aboriginal participants and were equally excessive among men and women.

  20. High-deposition-rate ceramics synthesis

    SciTech Connect

    Allendorf, M.D.; Osterheld, T.H.; Outka, D.A.

    1995-05-01

    Parallel experimental and computational investigations are conducted in this project to develop validated numerical models of ceramic synthesis processes. Experiments are conducted in the High-Temperature Materials Synthesis Laboratory in Sandia`s Combustion Research Facility. A high-temperature flow reactor that can accommodate small preforms (1-3 cm diameter) generates conditions under which deposition can be observed, with flexibility to vary both deposition temperature (up to 1500 K) and pressure (as low as 10 torr). Both mass spectrometric and laser diagnostic probes are available to provide measurements of gas-phase compositions. Experiments using surface analytical techniques are also applied to characterize important processes occuring on the deposit surface. Computational tools developed through extensive research in the combustion field are employed to simulate the chemically reacting flows present in typical industrial reactors. These include the CHEMKIN and Surface-CHEMKIN suites of codes, which permit facile development of complex reaction mechanisms and vastly simplify the implementation of multi-component transport and thermodynamics. Quantum chemistry codes are also used to estimate thermodynamic and kinetic data for species and reactions for which this information is unavailable.

  1. Lactate and rate of perceived exertion responses of athletes training for and competing in a mixed martial arts event.

    PubMed

    Amtmann, John A; Amtmann, Kelly A; Spath, William K

    2008-03-01

    Lactate and rate of perceived exertion (RPE) was monitored in 6 male subjects training for and competing in a mixed martial arts event held in Butte, Montana, to determine 1) the metabolic demands of the sport and 2) the effectiveness of the prebout interval training programs chosen to help prepare the competitors for this event. The training lactate measurements ranged from 8.1 to 19.7 mmol.L, and the training RPE levels ranged from 15 to 19 on Borg's Category Scale of perceived exertion, the scores of which ranged from 6 to 20. The postbout lactate measurements ranged from 10.2 to 20.7 mmol.L, and the post-bout RPE measurements ranged from 13 to 19. Of the 4 subjects that had both training and postbout lactate measurements, 3 had obtained lactate levels during training that exceeded lactate levels immediately after the bout. This indicated that, when using lactate measurements as a benchmark, the conditioning training was effective for these 3 athletes. When we used RPE scores as a benchmark, the conditioning was effective for all 4 subjects because all subjects reached 18-19 during their training, which was at least as high as their reported post-bout RPE levels.

  2. High resolution, high rate X-ray spectrometer

    DOEpatents

    Goulding, Frederick S.; Landis, Donald A.

    1987-01-01

    A pulse processing system (10) for use in an X-ray spectrometer in which a ain channel pulse shaper (12) and a fast channel pulse shaper (13) each produce a substantially symmetrical triangular pulse (f, p) for each event detected by the spectrometer, with the pulse width of the pulses being substantially independent of the magnitude of the detected event and with the pulse width of the fast pulses (p) being substantially shorter than the pulse width of the main channel pulses (f). A pile-up rejector circuit (19) allows output pulses to be generated, with amplitudes linearly related to the magnitude of the detected events, whenever the peak of a main channel pulse (f) is not affected by a preceding or succeeding main channel pulse, while inhibiting output pulses wherein peak magnitudes of main channel pulses are affected by adjacent pulses. The substantially symmetrical triangular main channel pulses (f) are generated by the weighted addition (27-31) of successive RC integrations (24, 25, 26) of an RC differentiated step wave (23). The substantially symmetrical triangular fast channel pulses (p) are generated by the RC integration ( 43) of a bipolar pulse (o) in which the amplitude of the second half is 1/e that of the first half, with the RC time constant of integration being equal to one-half the width of the bipolar pulse.

  3. High rate fabrication of compression molded components

    DOEpatents

    Matsen, Marc R.; Negley, Mark A.; Dykstra, William C.; Smith, Glen L.; Miller, Robert J.

    2016-04-19

    A method for fabricating a thermoplastic composite component comprises inductively heating a thermoplastic pre-form with a first induction coil by inducing current to flow in susceptor wires disposed throughout the pre-form, inductively heating smart susceptors in a molding tool to a leveling temperature with a second induction coil by applying a high-strength magnetic field having a magnetic flux that passes through surfaces of the smart susceptors, shaping the magnetic flux that passes through surfaces of the smart susceptors to flow substantially parallel to a molding surface of the smart susceptors, placing the heated pre-form between the heated smart susceptors; and applying molding pressure to the pre-form to form the composite component.

  4. Does Prison Crowding Predict Higher Rates of Substance Use Related Parole Violations? A Recurrent Events Multi-Level Survival Analysis

    PubMed Central

    Ruderman, Michael A.; Wilson, Deirdra F.; Reid, Savanna

    2015-01-01

    Objective This administrative data-linkage cohort study examines the association between prison crowding and the rate of post-release parole violations in a random sample of prisoners released with parole conditions in California, for an observation period of two years (January 2003 through December 2004). Background Crowding overextends prison resources needed to adequately protect inmates and provide drug rehabilitation services. Violence and lack of access to treatment are known risk factors for drug use and substance use disorders. These and other psychosocial effects of crowding may lead to higher rates of recidivism in California parolees. Methods Rates of parole violation for parolees exposed to high and medium levels of prison crowding were compared to parolees with low prison crowding exposure. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using a Cox model for recurrent events. Our dataset included 13070 parolees in California, combining individual level parolee data with aggregate level crowding data for multilevel analysis. Results Comparing parolees exposed to high crowding with those exposed to low crowding, the effect sizes from greatest to least were absconding violations (HR 3.56 95% CI: 3.05–4.17), drug violations (HR 2.44 95% CI: 2.00–2.98), non-violent violations (HR 2.14 95% CI: 1.73–2.64), violent and serious violations (HR 1.88 95% CI: 1.45–2.43), and technical violations (HR 1.86 95% CI: 1.37–2.53). Conclusions Prison crowding predicted higher rates of parole violations after release from prison. The effect was magnitude-dependent and particularly strong for drug charges. Further research into whether adverse prison experiences, such as crowding, are associated with recidivism and drug use in particular may be warranted. PMID:26492490

  5. Does Prison Crowding Predict Higher Rates of Substance Use Related Parole Violations? A Recurrent Events Multi-Level Survival Analysis.

    PubMed

    Ruderman, Michael A; Wilson, Deirdra F; Reid, Savanna

    2015-01-01

    This administrative data-linkage cohort study examines the association between prison crowding and the rate of post-release parole violations in a random sample of prisoners released with parole conditions in California, for an observation period of two years (January 2003 through December 2004). Crowding overextends prison resources needed to adequately protect inmates and provide drug rehabilitation services. Violence and lack of access to treatment are known risk factors for drug use and substance use disorders. These and other psychosocial effects of crowding may lead to higher rates of recidivism in California parolees. Rates of parole violation for parolees exposed to high and medium levels of prison crowding were compared to parolees with low prison crowding exposure. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using a Cox model for recurrent events. Our dataset included 13070 parolees in California, combining individual level parolee data with aggregate level crowding data for multilevel analysis. Comparing parolees exposed to high crowding with those exposed to low crowding, the effect sizes from greatest to least were absconding violations (HR 3.56 95% CI: 3.05-4.17), drug violations (HR 2.44 95% CI: 2.00-2.98), non-violent violations (HR 2.14 95% CI: 1.73-2.64), violent and serious violations (HR 1.88 95% CI: 1.45-2.43), and technical violations (HR 1.86 95% CI: 1.37-2.53). Prison crowding predicted higher rates of parole violations after release from prison. The effect was magnitude-dependent and particularly strong for drug charges. Further research into whether adverse prison experiences, such as crowding, are associated with recidivism and drug use in particular may be warranted.

  6. Particle production in very-high-energy cosmic-ray emulsion chamber events: Usual and unusual events

    NASA Astrophysics Data System (ADS)

    Costa, C. G. S.; Halzen, F.; Salles, C.

    1995-10-01

    We show that a simple scaling model of very forward particle production, consistent with accelerator and air shower data, can describe the overall features of the very-high-energy interactions recorded with emulsion chambers. The rapidity and transverse momentum distribution of the secondaries are quantitatively reproduced. This is somewhat surprising after numerous claims that the same data implied large scaling violations or new dynamics. Interestingly, we cannot describe some of the Centauro events, suggesting that these events are anomalous independently of their well-advertised unusual features such as the absence of neutral secondaries.

  7. High Strain Rate Tensile and Compressive Effects in Glassy Polymers

    DTIC Science & Technology

    2013-02-08

    polymers under high strain rates has been determined in compression. Some research programs have studied the combined effects of temperature and strain rate...glassy polymers to high strain rate loading in compression. More recently, research programs that study the combined effects of temperature and strain...Force Materiel Command  United States Air Force  Eglin Air Force Base AFRL-RW-EG-TP-2013-006 High Strain Rate

  8. Volcanic Event Recurrence Rate Model (VERRM): Incorporating Radiometric Ages, Volcanic Stratigraphy and Paleomagnetic Data into a Monte Carlo Simulation to Estimate Uncertainty in Recurrence Rate through Time

    NASA Astrophysics Data System (ADS)

    Wilson, J. A.; Richardson, J. A.

    2015-12-01

    Traditional methods used to calculate recurrence rate of volcanism, such as linear regression, maximum likelihood and Weibull-Poisson distributions, are effective at estimating recurrence rate and confidence level, but these methods are unable to estimate uncertainty in recurrence rate through time. We propose a new model for estimating recurrence rate and uncertainty, Volcanic Event Recurrence Rate Model. VERRM is an algorithm that incorporates radiometric ages, volcanic stratigraphy and paleomagnetic data into a Monte Carlo simulation, generating acceptable ages for each event. Each model run is used to calculate recurrence rate using a moving average window. These rates are binned into discrete time intervals and plotted using the 5th, 50th and 95th percentiles. We present recurrence rates from Cima Volcanic Field (CA), Yucca Mountain (NV) and Arsia Mons (Mars). Results from Cima Volcanic Field illustrate how several K-Ar ages with large uncertainties obscure three well documented volcanic episodes. Yucca Mountain results are similar to published rates and illustrate the use of using the same radiometric age for multiple events in a spatially defined cluster. Arsia Mons results show a clear waxing/waning of volcanism through time. VERRM output may be used for a spatio-temporal model or to plot uncertainty in quantifiable parameters such as eruption volume or geochemistry. Alternatively, the algorithm may be reworked to constrain geomagnetic chrons. VERRM is implemented in Python 2.7 and takes advantage of NumPy, SciPy and matplotlib libraries for optimization and quality plotting presentation. A typical Monte Carlo simulation of 40 volcanic events takes a few minutes to couple hours to complete, depending on the bin size used to assign ages.

  9. High data rate optical transceiver terminal

    NASA Technical Reports Server (NTRS)

    Clarke, E. S.

    1973-01-01

    The objectives of this study were: (1) to design a 400 Mbps optical transceiver terminal to operate from a high-altitude balloon-borne platform in order to permit the quantitative evaluation of a space-qualifiable optical communications system design, (2) to design an atmospheric propagation experiment to operate in conjunction with the terminal to measure the degrading effects of the atmosphere on the links, and (3) to design typical optical communications experiments for space-borne laboratories in the 1980-1990 time frame. As a result of the study, a transceiver package has been configured for demonstration flights during late 1974. The transceiver contains a 400 Mbps transmitter, a 400 Mbps receiver, and acquisition and tracking receivers. The transmitter is a Nd:YAG, 200 Mhz, mode-locked, CW, diode-pumped laser operating at 1.06 um requiring 50 mW for 6 db margin. It will be designed to implement Pulse Quaternary Modulation (PQM). The 400 Mbps receiver utilizes a Dynamic Crossed-Field Photomultiplier (DCFP) detector. The acquisition receiver is a Quadrant Photomultiplier Tube (QPMT) and receives a 400 Mbps signal chopped at 0.1 Mhz.

  10. An analysis of high-impact, low-predictive skill severe weather events in the northeast U.S

    NASA Astrophysics Data System (ADS)

    Vaughan, Matthew T.

    An objective evaluation of Storm Prediction Center slight risk convective outlooks, as well as a method to identify high-impact severe weather events with poor-predictive skill are presented in this study. The objectives are to assess severe weather forecast skill over the northeast U.S. relative to the continental U.S., build a climatology of high-impact, low-predictive skill events between 1980--2013, and investigate the dynamic and thermodynamic differences between severe weather events with low-predictive skill and high-predictive skill over the northeast U.S. Severe storm reports of hail, wind, and tornadoes are used to calculate skill scores including probability of detection (POD), false alarm ratio (FAR) and threat scores (TS) for each convective outlook. Low predictive skill events are binned into low POD (type 1) and high FAR (type 2) categories to assess temporal variability of low-predictive skill events. Type 1 events were found to occur in every year of the dataset with an average of 6 events per year. Type 2 events occur less frequently and are more common in the earlier half of the study period. An event-centered composite analysis is performed on the low-predictive skill database using the National Centers for Environmental Prediction Climate Forecast System Reanalysis 0.5° gridded dataset to analyze the dynamic and thermodynamic conditions prior to high-impact severe weather events with varying predictive skill. Deep-layer vertical shear between 1000--500 hPa is found to be a significant discriminator in slight risk forecast skill where high-impact events with less than 31-kt shear have lower threat scores than high-impact events with higher shear values. Case study analysis of type 1 events suggests the environment over which severe weather occurs is characterized by high downdraft convective available potential energy, steep low-level lapse rates, and high lifting condensation level heights that contribute to an elevated risk of severe wind.

  11. Cenozoic rejuvenation events of Massif Central topography (France): Insights from cosmogenic denudation rates and river profiles

    NASA Astrophysics Data System (ADS)

    Olivetti, Valerio; Godard, Vincent; Bellier, Olivier

    2016-06-01

    The French Massif Central is a part of the Hercynian orogenic belt that currently exhibits anomalously high topography. The Alpine orogenesis, which deeply marked Western European topography, involved only marginally the Massif Central, where Cenozoic faulting and short-wavelength crustal deformation is limited to the Oligocene rifting. For this reason the French Massif Central is a key site to study short- and long-term topographic response in a framework of slow tectonic activity. In particular the origin of the Massif Central topography is a topical issue still debated, where the role of mantle upwelling is invoked by different authors. Here we present a landscape analysis using denudation rates derived from basin-averaged cosmogenic nuclide concentrations coupled with longitudinal river profile analysis. This analysis allows us to recognize that the topography of the French Massif Central is not fully equilibrated with the present base level and in transient state. Our data highlight the coexistence of out-of-equilibrium river profiles, incised valleys, and low cosmogenically derived denudation rates ranging between 40 mm/kyr and 80 mm/kyr. Addressing this apparent inconsistency requires investigating the parameters that may govern erosion processes under conditions of reduced active tectonics. The spatial distribution of denudation rates coupled with topography analysis enabled us to trace the signal of the long-term uplift history and to propose a chronology for the uplift evolution of the French Massif Central.

  12. Biological impact of low dose-rate simulated solar particle event radiation in vivo.

    PubMed

    Chang, P Y; Doppalapudi, R; Bakke, J; Wang, A; Menda, S; Davis, Z

    2010-08-01

    C57Bl6-lacZ animals were exposed to a range of low dose-rate simulated solar particle event (sSPE) radiation at the NASA-sponsored Research Laboratory (NSRL) at Brookhaven National Laboratory (BNL). Peripheral blood was harvested from animals from 1 to 12 days after total body irradiation (TBI) to quantify the level of circulating reticulocytes (RET) and micronucleated reticulocytes (MN-RET) as an early indicator of radiation-induced genotoxicity. Bone marrow lymphocytes and hippocampal tissues from each animal were collected at 12 days and up to two months, to evaluate dose-dependent late effects after sSPE exposure. Early hematopoietic changes show that the % RET was reduced up to 3 days in response to radiation exposure but recovered at 12 days postirradiation. The % MN-RET in peripheral blood was temporally regulated and dependant on the total accumulated dose. Total chromosome aberrations in lymphocytes increased linearly with dose within a week after radiation and remained significantly higher than the control values at 4 weeks after exposure. The level of aberrations in the irradiated animals returned to control levels by 8 weeks postirradiation. Measurements of chromosome 2 and 8 specific aberrations indicate that, consistent with conventional giemsa-staining methods, the level of aberrations is also not significantly higher than in control animals at 8 weeks postirradiation. The hippocampus was surveyed for differential transcriptional regulation of genes known to be associated with neurogenesis. Our results showed differential expression of neurotrophin and their associated receptor genes within 1 week after sSPE exposure. Progressive changes in the profile of expressed genes known to be involved in neurogenic signaling pathways were dependent on the sSPE dose. Our results to date suggest that radiation-induced changes in the hematopoietic system, i.e., chromosome aberrations in lymphocytes, are transient and do not persist past 4 weeks after radiation

  13. Virus transcript levels and cell growth rates after naturally occurring HPV16 integration events in basal cervical keratinocytes.

    PubMed

    Scarpini, Cinzia G; Groves, Ian J; Pett, Mark R; Ward, Dawn; Coleman, Nicholas

    2014-07-01

    Cervical carcinogenesis is characterized by a clonal selection process in which the high-risk human papillomavirus (HRHPV) genome usually changes from the extra-chromosomal (episomal) state seen in productive infections to DNA that is integrated into host chromosomes. However, it is not clear whether all HRHPV integration events provide cells with a selective growth advantage compared with the episome-containing cells from which they originate. It is also unclear whether selection of cells containing a particular integrant from a mixed population simply reflects the highest levels of virus oncogene expression or has additional determinants. These early events in cervical carcinogenesis cannot readily be addressed by cross-sectional studies of clinical samples. We used the W12 model system to generate a panel of cervical squamous cell clones that were derived from an identical background under non-competitive conditions and differed only by the genomic site of HPV16 integration. Compared with the 'baseline' episome-containing cells from which they were isolated, only 9/17 clones (53%) showed significantly greater growth rates and only 7/17 (41%) showed significantly greater expression of the major virus oncogenes E7/E6. There were significant variations in levels of HPV16 transcription per DNA template, changes that were associated with histone modifications in the integrated virus chromatin. Cell growth rates showed only weak and non-significant associations with protein and mRNA levels for E7, E6, and the mean E7/E6 values. We conclude that HPV16 integration in basal cervical cells does not necessarily lead to increased levels of virus oncogenes, or to a competitive growth advantage, when compared with the initiating episome-containing cells.

  14. The Effect of Minimum Wage Rates on High School Completion

    ERIC Educational Resources Information Center

    Warren, John Robert; Hamrock, Caitlin

    2010-01-01

    Does increasing the minimum wage reduce the high school completion rate? Previous research has suffered from (1. narrow time horizons, (2. potentially inadequate measures of states' high school completion rates, and (3. potentially inadequate measures of minimum wage rates. Overcoming each of these limitations, we analyze the impact of changes in…

  15. The Effect of Minimum Wage Rates on High School Completion

    ERIC Educational Resources Information Center

    Warren, John Robert; Hamrock, Caitlin

    2010-01-01

    Does increasing the minimum wage reduce the high school completion rate? Previous research has suffered from (1. narrow time horizons, (2. potentially inadequate measures of states' high school completion rates, and (3. potentially inadequate measures of minimum wage rates. Overcoming each of these limitations, we analyze the impact of changes in…

  16. Asymptomatic pulmonary embolism: a common event in high risk patients

    SciTech Connect

    Williams, J.W.; Eikman, E.A.; Greenberg, S.

    1982-03-01

    Ventilation and perfusion lung scans were obtained before and at weekly intervals following hip surgery or major amputation in 158 patients. Pulmonary arteriograms were obtained in 21 of 33 patients developing perfusion patterns strongly suggesting embolism; 19 of the 21 arteriograms demonstrated pulmonary embolism. From autopsy and clinical data, 36 patients were diagnosed as having an embolus while under study, and 12 patients were suspected of having had an embolus during their illness but prior to entry into the study. Only four of these 48 patients experienced symptoms suggestive of pulmonary embolism. We conclude that asymptomatic pulmonary embolism is a common event in the populations studied.

  17. Reconstruction Software for High Multiplicity Events in GEM Detectors

    NASA Astrophysics Data System (ADS)

    Berretti, M.; Avati, V.; Bossini, E.; Brogi, P.; Brücken, E.; Giani, S.; Greco, V.; Lami, S.; Latino, G.; Oliveri, E.; Oljemark, F.; Österberg, K.; Scribano, A.; Turini, N.; Welti, J.

    2012-08-01

    We present a general description of the offline software developed for the reconstruction of inelastic events by the TOTEM T2 telescope at the LHC. Tracking reconstruction in the OMS forward region, where T2 is installed, is challenged by a large amount of charged particles generated by the interaction with the material placed between the IP and T2. In this contribution we describe the simulation of the T2 GEM chambers as well as the reconstruction procedures employed to track the particles in such severe environment. The strategy for the telescope alignment and the measurement of the charged particle pseudorapidity distribution is finally presented.

  18. Asymptomatic pulmonary embolism. A common event in high risk patients.

    PubMed Central

    Williams, J W; Eikman, E A; Greenberg, S

    1982-01-01

    Ventilation and perfusion lung scans were obtained before and at weekly intervals following hip surgery or major amputation in 158 patients. Pulmonary arteriograms were obtained in 21 of 33 patients developing perfusion patterns strongly suggesting embolism; 19 of the 21 arteriograms demonstrated pulmonary embolism. From autopsy and clinical data, 36 patients were diagnosed as having an embolus while under study, and 12 patients were suspected of having had an embolus during their illness but prior to entry into the study. Only four of these 48 patients experienced symptoms suggestive of pulmonary embolism. We conclude that asymptomatic pulmonary embolism is a common event in the populations studied. PMID:7059242

  19. Characterization of E. coli O157:H7 strains isolated from “High Event Period” beef trim contamination

    USDA-ARS?s Scientific Manuscript database

    Introduction: A “High Event Period” (HEP) is defined as a time period in which commercial plants experience a higher than usual rate of E. coli O157:H7 contamination of beef trims. Our previous studies suggested that instead of being a direct result of bacteria on animal hides, in-plant biofilm for...

  20. An evaluation of three signal-detection algorithms using a highly inclusive reference event database.

    PubMed

    Hochberg, Alan M; Hauben, Manfred; Pearson, Ronald K; O'Hara, Donald J; Reisinger, Stephanie J; Goldsmith, David I; Gould, A Lawrence; Madigan, David

    2009-01-01

    Pharmacovigilance data-mining algorithms (DMAs) are known to generate significant numbers of false-positive signals of disproportionate reporting (SDRs), using various standards to define the terms 'true positive' and 'false positive'. To construct a highly inclusive reference event database of reported adverse events for a limited set of drugs, and to utilize that database to evaluate three DMAs for their overall yield of scientifically supported adverse drug effects, with an emphasis on ascertaining false-positive rates as defined by matching to the database, and to assess the overlap among SDRs detected by various DMAs. A sample of 35 drugs approved by the US FDA between 2000 and 2004 was selected, including three drugs added to cover therapeutic categories not included in the original sample. We compiled a reference event database of adverse event information for these drugs from historical and current US prescribing information, from peer-reviewed literature covering 1999 through March 2006, from regulatory actions announced by the FDA and from adverse event listings in the British National Formulary. Every adverse event mentioned in these sources was entered into the database, even those with minimal evidence for causality. To provide some selectivity regarding causality, each entry was assigned a level of evidence based on the source of the information, using rules developed by the authors. Using the FDA adverse event reporting system data for 2002 through 2005, SDRs were identified for each drug using three DMAs: an urn-model based algorithm, the Gamma Poisson Shrinker (GPS) and proportional reporting ratio (PRR), using previously published signalling thresholds. The absolute number and fraction of SDRs matching the reference event database at each level of evidence was determined for each report source and the data-mining method. Overlap of the SDR lists among the various methods and report sources was tabulated as well. The GPS algorithm had the lowest

  1. High-Rate Data-Capture for an Airborne Lidar System

    NASA Technical Reports Server (NTRS)

    Valett, Susan; Hicks, Edward; Dabney, Philip; Harding, David

    2012-01-01

    A high-rate data system was required to capture the data for an airborne lidar system. A data system was developed that achieved up to 22 million (64-bit) events per second sustained data rate (1408 million bits per second), as well as short bursts (less than 4 s) at higher rates. All hardware used for the system was off the shelf, but carefully selected to achieve these rates. The system was used to capture laser fire, single-photon detection, and GPS data for the Slope Imaging Multi-polarization Photo-counting Lidar (SIMPL). However, the system has applications for other laser altimeter systems (waveform-recording), mass spectroscopy, xray radiometry imaging, high-background- rate ranging lidar, and other similar areas where very high-speed data capture is needed. The data capture software was used for the SIMPL instrument that employs a micropulse, single-photon ranging measurement approach and has 16 data channels. The detected single photons are from two sources those reflected from the target and solar background photons. The instrument is non-gated, so background photons are acquired for a range window of 13 km and can comprise many times the number of target photons. The highest background rate occurs when the atmosphere is clear, the Sun is high, and the target is a highly reflective surface such as snow. Under these conditions, the total data rate for the 16 channels combined is expected to be approximately 22 million events per second. For each photon detection event, the data capture software reads the relative time of receipt, with respect to a one-per-second absolute time pulse from a GPS receiver, from an event timer card with 0.1-ns precision, and records that information to a RAID (Redundant Array of Independent Disks) storage device. The relative time of laser pulse firings must also be read and recorded with the same precision. Each of the four event timer cards handles the throughput from four of the channels. For each detection event, a flag is

  2. Dose rate in brachytherapy using after-loading machine: pulsed or high-dose rate?

    PubMed

    Hannoun-Lévi, J-M; Peiffert, D

    2014-10-01

    Since February 2014, it is no longer possible to use low-dose rate 192 iridium wires due to the end of industrial production of IRF1 and IRF2 sources. The Brachytherapy Group of the French society of radiation oncology (GC-SFRO) has recommended switching from iridium wires to after-loading machines. Two types of after-loading machines are currently available, based on the dose rate used: pulsed-dose rate or high-dose rate. In this article, we propose a comparative analysis between pulsed-dose rate and high-dose rate brachytherapy, based on biological, technological, organizational and financial considerations.

  3. Calculated nuclide compositions and gamma-ray exposure rates for fallout from the HARRY, SMOKY, and ANNIE events

    SciTech Connect

    Hicks, H.G.

    1981-03-03

    The results of computer calculations of the nuclide composition and associated external gamma-ray exposure rates for fallout from the HARRY, SMOKY, and ANNIE events are documented. The fission product distribution is calculated for each event with the appropriate neutron spectrum and the fractions of fissions due to each fissionable material. Also calculated are the total number of microcuries per square meter and the gamma-ray exposure rates (mR/h, 1 meter above ground level) for the 152 fission products and 25 neutron-induced nuclides. The normalized data are presented in 9 Appendices. (DLS)

  4. Investigation of stability characteristics of cold-season convective precipitation events by utilizing the growth rate parameter

    NASA Astrophysics Data System (ADS)

    Melick, Christopher J.; Market, Patrick S.; Smith, Larry L.; Pettegrew, Brian P.; Becker, Amy E.; Lupo, Anthony R.

    2008-04-01

    The seldom utilized growth rate parameter (σ2), which predicts how rapidly a small-amplitude disturbance will grow in a conditional symmetrically unstable environment, was applied to study the stability characteristics of convective precipitation case studies across the central United States during the winter seasons of 2003-2004 and 2004-2005. The goals were to improve our understanding of how the environment becomes destabilized over a relatively short period of time, as well as to determine approximately where and when elevated thunderstorms are likely to develop. The comprehensive evaluation comprised a case study example and summary of statistics obtained by tabulations at the initiation site and spatial compositing of all case studies identified. The doubling time for the convection (the time required for a convective element to achieve twice its current depth) was found to be on the order of 1.3 h, which is consistent with the typical timescale for moist slantwise convection resulting from the release of conditional symmetric instability. The development of cold-season precipitation with lightning (i.e., thundersnow) and any associated banding was correctly and most accurately predicted from trends in plots of σ2 analyzed at the level at which the highest significant growth rates occurred. While this naturally varied from one event to the next, the average elevation tended to be close to 650 hPa. Furthermore, a term-by-term diagnosis of the mathematical expression for the growth rate was determined to be quite useful as another means of identifying the type of instability released within instances of wintertime convection. By calculating the individual contributions to the growth rate and observing whether a positive or negative response was obtained, the nature of the stability regime present was also ascertained. The inclusion of a set of non-thundering snowstorms helped to substantiate the assumption that atmospheres are less stable and more susceptible

  5. On the variation of the sun's X ray background flux and its relation to the sun's flaring rate, energetic event rate, and the solar cycle

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    1993-01-01

    Daily averages of the sun's X-ray background flux as measured by the GOES satellite are combined to yield monthly means and 'smoothed' monthly means (12-month moving averages) for the interval January 1986 through May 1992 (minimum rise, maximum, and initial decline of solar cycle 22). These averages are then compared directly to the sun's optical flaring rate, energetic event rate, and the usual markers of the solar cycle (e.g., sunspot number, total corrected sunspot area, and 10.7-cm solar radio flux, number of groups, and number of spots). The results of this analysis support previous findings that there exists a remarkably close positive relationship between the optical flaring rate and the X-ray background flux rate (the independent variable), and that the X-ray background flux rate can be used as a proxy for the solar cycle. Additionally, this study has found that a strong positive relationship exists between the energetic event rate and the X-ray background flux rate (the independent variable), and that the lag between the maxima of the rates of optical flaring and X-ray background flux reported for cycle 21 did not recur for cycle 22.

  6. On the variation of the sun's X ray background flux and its relation to the sun's flaring rate, energetic event rate, and the solar cycle

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    1993-01-01

    Daily averages of the sun's X-ray background flux as measured by the GOES satellite are combined to yield monthly means and 'smoothed' monthly means (12-month moving averages) for the interval January 1986 through May 1992 (minimum rise, maximum, and initial decline of solar cycle 22). These averages are then compared directly to the sun's optical flaring rate, energetic event rate, and the usual markers of the solar cycle (e.g., sunspot number, total corrected sunspot area, and 10.7-cm solar radio flux, number of groups, and number of spots). The results of this analysis support previous findings that there exists a remarkably close positive relationship between the optical flaring rate and the X-ray background flux rate (the independent variable), and that the X-ray background flux rate can be used as a proxy for the solar cycle. Additionally, this study has found that a strong positive relationship exists between the energetic event rate and the X-ray background flux rate (the independent variable), and that the lag between the maxima of the rates of optical flaring and X-ray background flux reported for cycle 21 did not recur for cycle 22.

  7. ASIC for High Rate 3D Position Sensitive Detectors

    SciTech Connect

    Vernon, E.; De Geronimo, G.; Ackley, K.; Fried, J.; He, Z.; Herman, C.; Zhang, F.

    2010-06-16

    We report on the development of an application specific integrated circuit (ASIC) for 3D position sensitive detectors (3D PSD). The ASIC is designed to operate with pixelated wide bandgap sensors like Cadmium-Zinc-Telluride (CZT), Mercuric Iodide (Hgl2) and Thallium Bromide (TIBr). It measures the amplitudes and timings associated with an ionizing event on 128 anodes, the anode grid, and the cathode. Each channel provides low-noise charge amplification, high-order shaping with peaking time adjustable from 250 ns to 12 {micro}s, gain adjustable to 20 mV/fC or 120 mV/fC (for a dynamic range of 3.2 MeV and 530 keV in CZT), amplitude discrimination with 5-bit trimming, and positive and negative peak and timing detections. The readout can be full or sparse, based on a flag and single- or multi-cycle token passing. All channels, triggered channels only, or triggered with neighbors can be read out thus increasing the rate capability of the system to more than 10 kcps. The ASIC dissipates 330 mW which corresponds to about 2.5 mW per channel.

  8. DSN acquisition of Magellan high-rate telemetry data

    NASA Technical Reports Server (NTRS)

    Berman, A. L.; Au, P. A.

    1992-01-01

    The Magellan Project levied the stringent requirement of a 98-percent high-rate telemetry data capture rate on the Deep Space Network (DSN) during the Magellan Prime Mapping Mission. To meet this requirement, the DSN undertook extensive development of the DSN Telemetry System, as well as extensive DSN operations planning and test and training. In actuality, the DSN substantially exceeded the requirement by achieving a Prime Mapping Mission high-rate telemetry data capture rate of 99.14 percent. This article details the DSN telemetry system development and DSN operations planning and test and training. In addition, the actual high-rate telemetry data outages are comprehensively presented and analyzed.

  9. DSN acquisition of Magellan high-rate telemetry data

    NASA Technical Reports Server (NTRS)

    Berman, A. L.; Au, P. A.

    1992-01-01

    The Magellan Project levied the stringent requirement of a 98 percent high-rate telemetry data capture rate on the Deep Space Network (DSN) during the Magellan Prime Mapping Mission. To meet this requirement, the DSN undertook extensive development of the DSN Telemetry System, as well as extensive DSN operation planning and test and training. In actuality, the DSN substantially exceeded the requirement by achieving a Prime Mapping Mission high-rate telemetry data capture rate of 99.14 percent. This article details the DSN telemetry system development, and DSN operations planning and test and training. In addition, the actual high-rate telemetry data outages are comprehensively presented and analyzed.

  10. Modeling Rare Events in High Dimensional Stochastics Systems

    SciTech Connect

    Darve, Eric

    2015-06-22

    The main issue addressed in this note is the study of an algorithm to accelerate the computation of kinetic rates in the context of molecular dynamics(MD). It is based on parallel simulations of short-time trajectories and its main components are: a decomposition of phase space into macrostates or cells, a resampling procedure that ensures that the number of parallel replicas (MD simulations) in each macro-state remains constant, the use of multiple populations (colored replicas) to compute multiple rates (e.g., forward and backward rates) in one simulation. The method leads to enhancing the sampling of macro-states associated to the transition states, since in traditional MD these are likely to be depleted even after short-time simulations. By allowing parallel replicas to carry different probabilistic weights, the number of replicas within each macro-state can be maintained constant without introducing any bias. The empirical variance of the estimated reaction rate, defined as a probability flux, is expectedly diminished. This note is a first attempt towards a better mathematical and numerical understanding of this method. It provides first a mathematical formalization of the notion of colors. Then, the link between this algorithm and a set of closely related methods having been proposed in the literature within the past few years is discussed. Lastly, numerical results are provided that illustrate the efficiency of the method.

  11. High-Rate Strong-Signal Quantum Cryptography

    NASA Technical Reports Server (NTRS)

    Yuen, Horace P.

    1996-01-01

    Several quantum cryptosystems utilizing different kinds of nonclassical lights, which can accommodate high intensity fields and high data rate, are described. However, they are all sensitive to loss and both the high rate and the strong-signal character rapidly disappear. A squeezed light homodyne detection scheme is proposed which, with present-day technology, leads to more than two orders of magnitude data rate improvement over other current experimental systems for moderate loss.

  12. High Strain Rate Mechanical Properties of Glassy Polymers

    DTIC Science & Technology

    2012-07-25

    Force Materiel Command  United States Air Force  Eglin Air Force Base AFRL-RW-EG-TP-2012-008 High Strain Rate...TITLE AND SUBTITLE High Strain Rate Mechanical Properties of Glassy Polymers 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...1990s, a range of experimental data has been generated describing the response of glassy polymers to high strain rate loading in compression. More

  13. Strain rate effect in high-speed wire drawing process

    NASA Astrophysics Data System (ADS)

    He, S.; Van Houtte, P.; Van Bael, A.; Mei, F.; Sarban, A.; Boesman, P.; Galvez, F.; Atienza, J. M.

    2002-05-01

    This paper presents a study on the strain rate effect during high-speed wire drawing process by means of finite element simulation. Based on the quasistatic stresses obtained by normal tensile tests and dynamic stresses at high strain rates by split Hopkinson pressure bar tests, the wire drawing process was simulated for low carbon steel and high carbon steel. The results show that both the deformation process and the final properties of drawn wires are influenced by the strain rate.

  14. Between-register and within-register variability in event-finding and rates in the MONICA-France Project.

    PubMed

    Richard, J L; Arveiler, D; Cambou, J P; Nuttens, M C; Bingham, A; Ruidavets, J B; Schaffer, P; Salomez, J L; Douste-Blazy, P

    1990-01-01

    The 1985 and 1986 coronary event data from the three French MONICA Registers in Haute-Garonne (Toulouse), Bas-Rhin (Strasbourg) and the Urban Community of Lille (UCL) are used to compare the sources of information, the distribution of events in different diagnostic categories, and their possible effects on event rates. All three registers follow the MONICA protocol, and use the "cold pursuit" method, with data abstracted retrospectively from medical files or from the doctors establishing the causes of death. The health system and medical background are similar in the three centers. The distribution of the sources of information (in-hospital and out-of-hospital) and the distribution of events by diagnostic categories are different among centres. The possible effects of these differences on rates of definite myocardial infarction or possible coronary death are estimated between registers and within registers during a 2-year period. Cross-sectional comparisons are questionable, and possible false trends in event rates require special attention.

  15. High strain rate modeling of ceramics and ceramic composites

    NASA Astrophysics Data System (ADS)

    Espinosa, H. D.

    1994-07-01

    The high strain rate response of an AlN/AlN/Al composite manufactured by Lanxide Armor Products, Inc., has been studied through normal and pressure-shear plate impact experiments. Differences in the measured shear resistance, as a function of the impact configuration, motivated the examination of the material response by means of a microcracking multiple-plane model and a continuum elasto-viscoplastic constitutive model. Numerical simulations of the normal impact experiments do not support microcracking as the dominant inelastic mechanism. By contrast, an elasto-viscoplastic description of the material behavior predicts the main features of the normal stress history and the thickness dependence of the Hugoniot elastic limit. Nonetheless, the elasto-viscoplastic model cannot reproduce both the normal and pressure-shear experiments with a single set of model parameters. The inadequacy of the continuum elasto-viscoplastic model seems to result from the isotropic assumption embodied in its formulation. The shear resistance measured in the pressure-shear experiments is adequately predicted by a microcracking multiple-plane model. The agreement seems to hinge in the continuous shearing of the material on a micro-localized fashion, i.e. only one orientation becomes dominant and controls the inelastic shear deformation rate. This event does not occur in the normal impact configuration, in which the amount of inelasticity is primarily controlled by the elastic compressibility of the material. These findings explain the higher sensitivity to damage and microplasticity observed in the pressure-shear configuration, as well as the softer material response recorded in this configuration.

  16. Constraining the rate of oceanic deoxygenation leading up to a Cretaceous Oceanic Anoxic Event (OAE-2: ~94 Ma)

    PubMed Central

    Ostrander, Chadlin M.; Owens, Jeremy D.; Nielsen, Sune G.

    2017-01-01

    The rates of marine deoxygenation leading to Cretaceous Oceanic Anoxic Events are poorly recognized and constrained. If increases in primary productivity are the primary driver of these episodes, progressive oxygen loss from global waters should predate enhanced carbon burial in underlying sediments—the diagnostic Oceanic Anoxic Event relic. Thallium isotope analysis of organic-rich black shales from Demerara Rise across Oceanic Anoxic Event 2 reveals evidence of expanded sediment-water interface deoxygenation ~43 ± 11 thousand years before the globally recognized carbon cycle perturbation. This evidence for rapid oxygen loss leading to an extreme ancient climatic event has timely implications for the modern ocean, which is already experiencing large-scale deoxygenation. PMID:28808684

  17. Constraining the rate of oceanic deoxygenation leading up to a Cretaceous Oceanic Anoxic Event (OAE-2: ~94 Ma).

    PubMed

    Ostrander, Chadlin M; Owens, Jeremy D; Nielsen, Sune G

    2017-08-01

    The rates of marine deoxygenation leading to Cretaceous Oceanic Anoxic Events are poorly recognized and constrained. If increases in primary productivity are the primary driver of these episodes, progressive oxygen loss from global waters should predate enhanced carbon burial in underlying sediments-the diagnostic Oceanic Anoxic Event relic. Thallium isotope analysis of organic-rich black shales from Demerara Rise across Oceanic Anoxic Event 2 reveals evidence of expanded sediment-water interface deoxygenation ~43 ± 11 thousand years before the globally recognized carbon cycle perturbation. This evidence for rapid oxygen loss leading to an extreme ancient climatic event has timely implications for the modern ocean, which is already experiencing large-scale deoxygenation.

  18. Frequent nucleation events at the high altitude station of Chacaltaya (5240 m a.s.l.), Bolivia

    NASA Astrophysics Data System (ADS)

    Rose, C.; Sellegri, K.; Velarde, F.; Moreno, I.; Ramonet, M.; Weinhold, K.; Krejci, R.; Ginot, Patrick; Andrade, M.; Wiedensohler, A.; Laj, P.

    2015-02-01

    While nucleation may represent one of the major processes responsible for the total aerosol number burden in the atmosphere, and especially at high altitude, new particle formation (NPF) events occurring in the upper part of the troposphere are poorly documented in the literature, particularly in the southern hemisphere. NPF events were detected and analyzed at the highest measurement site in the world, Chacaltaya (5240 m a.s.l.), Bolivia between January 1 and December 31 2012, using a Neutral Aerosol and Ion Spectrometer (NAIS) that detects clusters down to 0.4 nm. NPF frequency at Chacaltaya is one of the highest reported so far (63.9%) and shows a clear seasonal dependency with maximum up to 100% during the dry season. This high seasonality of the NPF events frequency was found to be likely linked to the presence of clouds in the vicinity of the station during the wet season. Multiple NPF events are seen on almost 50% of event days and can reach up to 6 events per day, increasing the potential of nucleation to be the major contributor to the particle number concentrations in the upper troposphere. Ion-induced nucleation (IIN) was 14.8% on average, which is higher than the IIN fractions reported for boundary layer stations. The median formation rate of 2 nm particles computed for first position events is increased during the dry season (1.90 cm-3 s-1) compared to the wet season (1.02 cm-3 s-1), showing that events are more intense, on top of being more frequent during the dry season. On the contrary, particle growth rates (GRs) are on average enhanced during the wet season, which could be explained by higher amount of biogenic volatile organic compounds transported from the Amazon rainforest. The NPF events frequency is clearly enhanced when air masses originate from the oceanic sector, with a frequency of occurrence close to 1. However, based on the particle GRs, we calculate that particles most likely nucleate after the oceanic air masses reach the land and are

  19. Trauma and recent life events in individuals at ultra high risk for psychosis: review and meta-analysis.

    PubMed

    Kraan, Tamar; Velthorst, Eva; Smit, Filip; de Haan, Lieuwe; van der Gaag, Mark

    2015-02-01

    Childhood trauma and recent life-events have been related to psychotic disorders. The aim of the present study was to examine whether childhood trauma and recent life-events are significantly more prevalent in patients at Ultra High Risk (UHR) of developing a psychotic disorder compared to healthy controls. A search of PsychInfo and Embase was conducted, relevant papers were reviewed, and three random-effects meta-analyses were performed. One meta-analysis assessed the prevalence rate of childhood trauma in UHR subjects and two meta-analyses were conducted to compare UHR subjects and healthy control subjects on the experience of childhood trauma and recent life-events. We found 12 studies on the prevalence of (childhood) trauma in UHR populations and 4 studies on recent life-events in UHR populations. We performed a meta-analysis on 6 studies (of which trauma prevalence rates were available) on childhood trauma in UHR populations, yielding a mean prevalence rate of 86.8% (95% CI 77%-93%). Childhood trauma was significantly more prevalent in UHR subjects compared to healthy control groups (Random effects Hedges' g=1.09; Z=4.60, p<.001). In contrast to our hypothesis, life-event rates were significantly lower in UHR subjects compared to healthy controls (Random effects Hedges' g=-0.53; Z=-2.36, p<.02). Our meta-analytic results illustrate that childhood trauma is highly prevalent among UHR subjects and that childhood trauma is related to UHR status. These results are in line with studies on childhood trauma in psychotic populations. In contrast to studies on recent life-events in psychotic populations, our results show that recent life-events are not associated with UHR status. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Some properties of field-aligned electron events in high-altitude polar regions

    NASA Astrophysics Data System (ADS)

    Zhang, ZiYing; Shi, JianKui; Zhou, MingQuan; Cheng, ZhengWei; Zhou, Hua

    2016-02-01

    Using data from the Cluster spacecraft from January 2003 to December 2004, we perform a statistical study on some properties of the field-aligned electron (FAE) events and interplanetary magnetic field (IMF) By dependence of FAE events with different durations in high-altitude polar regions. A total of 1335 FAE events were observed by the C3 spacecraft. More down-flowing events were observed in the Southern Hemisphere, and more up-flowing events were observed in the Northern Hemisphere. It proves that down-flowing events mainly originate from magnetosphere or solar wind and up-flowing events are mainly derived from ionosphere. Short-lifetime events showed a morning concentration in the magnetic local time distribution, and long-lifetime events were concentrated both before and after noon. For the IMF By dependence of the FAE events, short-lifetime events were much affected by IMF By and resulted in a morning concentration, while the long-lifetime events were almost unaffected by IMF By. With further analysis, we determined that the short-lifetime and long-lifetime events had different sources.

  1. Aggressive Students and High School Dropout: An Event History Analysis

    ERIC Educational Resources Information Center

    Orozco, Steven R.

    2016-01-01

    Aggressive students often struggle in multiple domains of their school functioning and are at increased risk for high school dropout. Research has identified a variety of warning flags which are strong predictors of high school dropout. While it is known that aggressive students exhibit many of these warning flags, there is little research which…

  2. Aggressive Students and High School Dropout: An Event History Analysis

    ERIC Educational Resources Information Center

    Orozco, Steven R.

    2016-01-01

    Aggressive students often struggle in multiple domains of their school functioning and are at increased risk for high school dropout. Research has identified a variety of warning flags which are strong predictors of high school dropout. While it is known that aggressive students exhibit many of these warning flags, there is little research which…

  3. Estimating the molecular evolutionary rates of mitochondrial genes referring to Quaternary ice age events with inferred population expansions and dispersals in Japanese Apodemus.

    PubMed

    Suzuki, Yutaro; Tomozawa, Morihiko; Koizumi, Yuki; Tsuchiya, Kimiyuki; Suzuki, Hitoshi

    2015-09-15

    Determining reliable evolutionary rates of molecular markers is essential in illustrating historical episodes with phylogenetic inferences. Although emerging evidence has suggested a high evolutionary rate for intraspecific genetic variation, it is unclear how long such high evolutionary rates persist because a recent calibration point is rarely available. Other than using fossil evidence, it is possible to estimate evolutionary rates by relying on the well-established temporal framework of the Quaternary glacial cycles that would likely have promoted both rapid expansion events and interisland dispersal events. We examined mitochondrial cytochrome b (Cytb) and control region (CR) gene sequences in two Japanese wood mouse species, Apodemus argenteus and A. speciosus, of temperate origin and found signs of rapid expansion in the population from Hokkaido, the northern island of Japan. Assuming that global warming after the last glacial period 7-10 thousand years before present (kyr BP) was associated with the expansion, the evolutionary rates (sites per million years, myr) of Cytb and CR were estimated as 11-16 % and 22-32 %, respectively, for A. argenteus, and 12-17 % and 17-24 %, respectively, for A. speciosus. Additionally, the significant signature of rapid expansion detected in the mtDNA sequences of A. speciosus from the remaining southern main islands, Honshu, Shikoku, and Kyushu, provided an estimated Cytb evolutionary rate of 3.1 %/site/myr under the assumption of a postglacial population expansion event long ago, most probably at 130 kyr BP. Bayesian analyses using the higher evolutionary rate of 11-17 %/site/myr for Cytb supported the recent demographic or divergence events associated with the Last Glacial Maximum. However, the slower evolutionary rate of 3.1 %/site/myr would be reasonable for several divergence events that were associated with glacial periods older than 130 kyr BP. The faster and slower evolutionary rates of Cytb can account for

  4. ATP binding and hydrolysis-driven rate-determining events in the RFC-catalyzed PCNA clamp loading reaction.

    PubMed

    Sakato, Miho; Zhou, Yayan; Hingorani, Manju M

    2012-02-17

    The multi-subunit replication factor C (RFC) complex loads circular proliferating cell nuclear antigen (PCNA) clamps onto DNA where they serve as mobile tethers for polymerases and coordinate the functions of many other DNA metabolic proteins. The clamp loading reaction is complex, involving multiple components (RFC, PCNA, DNA, and ATP) and events (minimally: PCNA opening/closing, DNA binding/release, and ATP binding/hydrolysis) that yield a topologically linked clamp·DNA product in less than a second. Here, we report pre-steady-state measurements of several steps in the reaction catalyzed by Saccharomyces cerevisiae RFC and present a comprehensive kinetic model based on global analysis of the data. Highlights of the reaction mechanism are that ATP binding to RFC initiates slow activation of the clamp loader, enabling it to open PCNA (at ~2 s(-1)) and bind primer-template DNA (ptDNA). Rapid binding of ptDNA leads to formation of the RFC·ATP·PCNA(open)·ptDNA complex, which catalyzes a burst of ATP hydrolysis. Another slow step in the reaction follows ATP hydrolysis and is associated with PCNA closure around ptDNA (8 s(-1)). Dissociation of PCNA·ptDNA from RFC leads to catalytic turnover. We propose that these early and late rate-determining events are intramolecular conformational changes in RFC and PCNA that control clamp opening and closure, and that ATP binding and hydrolysis switch RFC between conformations with high and low affinities, respectively, for open PCNA and ptDNA, and thus bookend the clamp loading reaction.

  5. High-impact hydrologic events and atmospheric rivers in California: An investigation using the NCEI Storm Events Database

    NASA Astrophysics Data System (ADS)

    Young, Allison M.; Skelly, Klint T.; Cordeira, Jason M.

    2017-04-01

    Atmospheric rivers (ARs) are long, narrow corridors of enhanced integrated water vapor and integrated vapor transport that can result in high-impact hydrologic events (HIHEs) including floods, flash floods, and debris flows. This study examined the relationship between HIHEs and ARs in California for 10 water years by using the National Centers for Environmental Information Storm Events Database and a catalog of landfalling ARs provided by Rutz et al. Results illustrated that HIHEs related to floods and debris flows are commonly associated with ARs during the cold season across Northern California, whereas HIHEs related to flash floods are commonly not associated with ARs during the warm season across Southern California. Composite analyses illustrated that HIHEs associated with landfalling ARs are associated with synoptic-scale flow patterns that support southwesterly water vapor flux that aligns favorably with California coastal topography to maximize upslope flow and orographic precipitation.

  6. High-shear-rate capillary viscometer for inkjet inks

    NASA Astrophysics Data System (ADS)

    Wang, Xi; Carr, Wallace W.; Bucknall, David G.; Morris, Jeffrey F.

    2010-06-01

    A capillary viscometer developed to measure the apparent shear viscosity of inkjet inks at high apparent shear rates encountered during inkjet printing is described. By using the Weissenberg-Rabinowitsch equation, true shear viscosity versus true shear rate is obtained. The device is comprised of a constant-flow generator, a static pressure monitoring device, a high precision submillimeter capillary die, and a high stiffness flow path. The system, which is calibrated using standard Newtonian low-viscosity silicone oil, can be easily operated and maintained. Results for measurement of the shear-rate-dependent viscosity of carbon-black pigmented water-based inkjet inks at shear rates up to 2×105 s-1 are discussed. The Cross model was found to closely fit the experimental data. Inkjet ink samples with similar low-shear-rate viscosities exhibited significantly different shear viscosities at high shear rates depending on particle loading.

  7. High-shear-rate capillary viscometer for inkjet inks

    SciTech Connect

    Wang Xi; Carr, Wallace W.; Bucknall, David G.; Morris, Jeffrey F.

    2010-06-15

    A capillary viscometer developed to measure the apparent shear viscosity of inkjet inks at high apparent shear rates encountered during inkjet printing is described. By using the Weissenberg-Rabinowitsch equation, true shear viscosity versus true shear rate is obtained. The device is comprised of a constant-flow generator, a static pressure monitoring device, a high precision submillimeter capillary die, and a high stiffness flow path. The system, which is calibrated using standard Newtonian low-viscosity silicone oil, can be easily operated and maintained. Results for measurement of the shear-rate-dependent viscosity of carbon-black pigmented water-based inkjet inks at shear rates up to 2x10{sup 5} s{sup -1} are discussed. The Cross model was found to closely fit the experimental data. Inkjet ink samples with similar low-shear-rate viscosities exhibited significantly different shear viscosities at high shear rates depending on particle loading.

  8. Techniques of Microprocessor Testing and SEU (Single Event Upset)-Rate Prediction.

    DTIC Science & Technology

    1986-08-15

    be tested in a simple computer configuration, e.g., single board computer . The proces- sor "self-tests"~ and the result of the self-test can be...register or in the program counter. Following such an event, the single board computer would sometimes lose track of itself, and a catastrophic

  9. Gender Differences in Traumatic Events and Rates of Post-Traumatic Stress Disorder among Homeless Youth

    ERIC Educational Resources Information Center

    Gwadz, Marya Viorst; Nish, David; Leonard, Noelle R.; Strauss, Shiela M.

    2007-01-01

    In the present report we describe patterns of traumatic events and Post-traumatic Stress Disorder (PTSD), both partial and full, among homeless youth and those at risk for homelessness, with an emphasis on gender differences. Participants were 85 homeless and at-risk youth (49% female) recruited from a drop-in center in New York City in 2000.…

  10. Gender Differences in Traumatic Events and Rates of Post-Traumatic Stress Disorder among Homeless Youth

    ERIC Educational Resources Information Center

    Gwadz, Marya Viorst; Nish, David; Leonard, Noelle R.; Strauss, Shiela M.

    2007-01-01

    In the present report we describe patterns of traumatic events and Post-traumatic Stress Disorder (PTSD), both partial and full, among homeless youth and those at risk for homelessness, with an emphasis on gender differences. Participants were 85 homeless and at-risk youth (49% female) recruited from a drop-in center in New York City in 2000.…

  11. HIGH-RATE DISINFECTION TECHNIQUES FOR COMBIND SEWER OVERFLOW

    EPA Science Inventory

    This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH )...

  12. High Graduate Unemployment Rate and Taiwanese Undergraduate Education

    ERIC Educational Resources Information Center

    Wu, Chih-Chun

    2011-01-01

    An expansion in higher education in combination with the recent global economic recession has resulted in a high college graduate unemployment rate in Taiwan. This study investigates how the high unemployment rate and financial constraints caused by economic cutbacks have shaped undergraduates' class choices, job needs, and future income…

  13. HIGH-RATE DISINFECTION TECHNIQUES FOR COMBIND SEWER OVERFLOW

    EPA Science Inventory

    This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH )...

  14. The impact of extended-hours home hemodialysis and buttonhole cannulation technique on hospitalization rates for septic events related to dialysis access.

    PubMed

    Van Eps, Carolyn L; Jones, Mark; Ng, Tsun; Johnson, David W; Campbell, Scott B; Isbel, Nicole M; Mudge, David W; Beller, Elaine; Hawley, Carmel M

    2010-10-01

    Few studies adequately document adverse events in patients receiving long, slow, and overnight hemodialysis (NHD). Concerns about high rates of dialysis access complications have been raised. This is an observational cohort study comparing hospital admission rates for vascular access complications between alternate nightly NHD (n=63) and conventional hemodialysis (n=172) patients established on chronic hemodialysis for at least 3 months. Overall, hospital admission rates and hospital admission rates for cardiac and all infective events are also reported. The NHD cohort was younger and less likely to be female, diabetic, or have ischemic heart disease than the conventional hemodialysis cohort. When NHD and buttonhole cannulation technique were used simultaneously, there was a demonstrated increased risk of septic dialysis access events: incidence rate ratio 3.0 (95% confidence interval 1.04-8.66) (P=0.04). The majority of blood culture isolates in NHD patients were gram-positive organisms, particularly Staphylococcus aureus. Alternate nightly NHD did not significantly change total hospital admissions or hospital admissions for indications other than dialysis access complications, compared with conventional hemodialysis. Our data suggest that buttonhole cannulation technique should be used with caution in patients performing extended-hours hemodialysis as this combination appears to increase the risk of septic access complications. Randomized-controlled trials are needed to confirm these findings. © 2010 The Authors. Hemodialysis International © 2010 International Society for Hemodialysis.

  15. Nitrogen accumulation and partitioning in a High Arctic tundra ecosystem from extreme atmospheric N deposition events.

    PubMed

    Choudhary, Sonal; Blaud, Aimeric; Osborn, A Mark; Press, Malcolm C; Phoenix, Gareth K

    2016-06-01

    Arctic ecosystems are threatened by pollution from recently detected extreme atmospheric nitrogen (N) deposition events in which up to 90% of the annual N deposition can occur in just a few days. We undertook the first assessment of the fate of N from extreme deposition in High Arctic tundra and are presenting the results from the whole ecosystem (15)N labelling experiment. In 2010, we simulated N depositions at rates of 0, 0.04, 0.4 and 1.2 g Nm(-2)yr(-1), applied as (15)NH4(15)NO3 in Svalbard (79(°)N), during the summer. Separate applications of (15)NO3(-) and (15)NH4(+) were also made to determine the importance of N form in their retention. More than 95% of the total (15)N applied was recovered after one growing season (~90% after two), demonstrating a considerable capacity of Arctic tundra to retain N from these deposition events. Important sinks for the deposited N, regardless of its application rate or form, were non-vascular plants>vascular plants>organic soil>litter>mineral soil, suggesting that non-vascular plants could be the primary component of this ecosystem to undergo measurable changes due to N enrichment from extreme deposition events. Substantial retention of N by soil microbial biomass (70% and 39% of (15)N in organic and mineral horizon, respectively) during the initial partitioning demonstrated their capacity to act as effective buffers for N leaching. Between the two N forms, vascular plants (Salix polaris) in particular showed difference in their N recovery, incorporating four times greater (15)NO3(-) than (15)NH4(+), suggesting deposition rich in nitrate will impact them more. Overall, these findings show that despite the deposition rates being extreme in statistical terms, biologically they do not exceed the capacity of tundra to sequester pollutant N during the growing season. Therefore, current and future extreme events may represent a major source of eutrophication. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  16. Test of Antonovsky's postulate: high sense of coherence helps people avoid negative life events.

    PubMed

    Hochwälder, Jacek

    2015-04-01

    This study tested Antonovsky's postulate that a high sense of coherence (SOC) helps people avoid negative life events. It was assumed that negative life events that were uncontrollable would not show this effect, while those events that potentially could be controlled would show a significant relationship with SOC. 1,012 female nurses (M age=46.9 yr.; SD=8.9) participated in this longitudinal study and were divided into groups with low, moderate, and high SOC. Sixteen negative life events were categorized into uncontrollable and controllable events, with the controllable events divided into three sub-categories. Five one-way analyses of variance (ANOVAs) for independent measures followed up with post hoc tests were performed, with the number of experienced events in a given category by each participant (at Time 2) as the dependent variable and the three SOC groups (formed at Time 1) as the independent variable. The results indicated that the high SOC group reported fewer controllable negative life events, while there was no significant relationship between the SOC level and uncontrollable negative life events. The findings support the postulate in Antonovsky's model, with the distinction between controllable and uncontrollable negative life events.

  17. Location of In-Hospital Cardiac Arrest in the United States-Variability in Event Rate and Outcomes.

    PubMed

    Perman, Sarah M; Stanton, Emily; Soar, Jasmeet; Berg, Robert A; Donnino, Michael W; Mikkelsen, Mark E; Edelson, Dana P; Churpek, Matthew M; Yang, Lin; Merchant, Raina M

    2016-09-29

    In-hospital cardiac arrest (IHCA) is a major public health problem with significant mortality. A better understanding of where IHCA occurs in hospitals (intensive care unit [ICU] versus monitored ward [telemetry] versus unmonitored ward) could inform strategies for reducing preventable deaths. This is a retrospective study of adult IHCA events in the Get with the Guidelines-Resuscitation database from January 2003 to September 2010. Unadjusted analyses were used to characterize patient, arrest, and hospital-level characteristics by hospital location of arrest (ICU versus inpatient ward). IHCA event rates and outcomes were plotted over time by arrest location. Among 85 201 IHCA events at 445 hospitals, 59% (50 514) occurred in the ICU compared to 41% (34 687) on the inpatient wards. Compared to ward patients, ICU patients were younger (64±16 years versus 69±14; P<0.001) and more likely to have a presenting rhythm of ventricular tachycardia/ventricular fibrillation (21% versus 17%; P<0.001). In the ICU, mean event rate/1000 bed-days was 0.337 (±0.215) compared with 0.109 (±0.079) for telemetry wards and 0.134 (±0.098) for unmonitored wards. Of patients with an arrest in the ICU, the adjusted mean survival to discharge was 0.140 (0.037) compared with the unmonitored wards 0.106 (0.037) and telemetry wards 0.193 (0.074). More IHCA events occurred in the ICU compared to the inpatient wards and there was a slight increase in events/1000 patient bed-days in both locations. Survival rates vary based on location of IHCA. Optimizing patient assignment to unmonitored wards versus telemetry wards may contribute to improved survival after IHCA. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  18. A high-speed DAQ framework for future high-level trigger and event building clusters

    NASA Astrophysics Data System (ADS)

    Caselle, M.; Ardila Perez, L. E.; Balzer, M.; Dritschler, T.; Kopmann, A.; Mohr, H.; Rota, L.; Vogelgesang, M.; Weber, M.

    2017-03-01

    Modern data acquisition and trigger systems require a throughput of several GB/s and latencies of the order of microseconds. To satisfy such requirements, a heterogeneous readout system based on FPGA readout cards and GPU-based computing nodes coupled by InfiniBand has been developed. The incoming data from the back-end electronics is delivered directly into the internal memory of GPUs through a dedicated peer-to-peer PCIe communication. High performance DMA engines have been developed for direct communication between FPGAs and GPUs using "DirectGMA (AMD)" and "GPUDirect (NVIDIA)" technologies. The proposed infrastructure is a candidate for future generations of event building clusters, high-level trigger filter farms and low-level trigger system. In this paper the heterogeneous FPGA-GPU architecture will be presented and its performance be discussed.

  19. DecisionFlow: Visual Analytics for High-Dimensional Temporal Event Sequence Data.

    PubMed

    Gotz, David; Stavropoulos, Harry

    2014-12-01

    Temporal event sequence data is increasingly commonplace, with applications ranging from electronic medical records to financial transactions to social media activity. Previously developed techniques have focused on low-dimensional datasets (e.g., with less than 20 distinct event types). Real-world datasets are often far more complex. This paper describes DecisionFlow, a visual analysis technique designed to support the analysis of high-dimensional temporal event sequence data (e.g., thousands of event types). DecisionFlow combines a scalable and dynamic temporal event data structure with interactive multi-view visualizations and ad hoc statistical analytics. We provide a detailed review of our methods, and present the results from a 12-person user study. The study results demonstrate that DecisionFlow enables the quick and accurate completion of a range of sequence analysis tasks for datasets containing thousands of event types and millions of individual events.

  20. Energy deposition and middle atmosphere electrodynamic response to a highly relativistic electron precipitation event

    NASA Technical Reports Server (NTRS)

    Goldberg, R. A.; Baker, D. N.; Herrero, F. A.; Mccarthy, S. P.; Twigg, P. A.; Croskey, C. L.; Hale, L. C.

    1994-01-01

    Rocket data have been used to evaluate the characteristics of precipitating relativistic electrons and their effects on the electrodynamic structure of the middle atmosphere. These data were obtained at Poker Flat, Alaska, on May 13 and 14, 1990, during a midday, highly relativistic electron (HRE) precipitation event. Solid state detectors were used to measure the electron fluxes and their energy spectra. An X ray scintillator was included on each flight to measure bremsstrahlung X rays produced by energetic electrons impacting on the upper atmosphere. However, these were found the be of negligible importance for this particular event. The energy deposition by the electrons has been determined from the flux measurements and compared with in situ measurements of the atmospheric electrical response. The electrodynamic measurements were obtained by the same rockets and additionally on May 13, with an accompanying rocket. The impact flux was highly irregular, containing short-lived bursts of relativistic electrons, mainly with energies below 0.5 MeV and with fluxes most enhanced between pitch angles of 0 deg - 20 deg. Although the geostationary counterpart of this measured event was considered to be of relatively low intensity and hardness, energy deposition peaked near 75 km with fluxes approaching an ion pair production rate in excess of 100/cu cm s. This exceeds peak fluxes in relativistic electron precipitation (REP) events as observed by us in numerous rocket soundings since 1976. Conductivity measurements from a blunt probe showed that negative electrical conductivities exceeded positive conductivities down to 50 km or lower, consistent with steady ionization by precipitating electrons above 1 MeV. These findings imply that the electrons from the outer radiation zone can modulate the electrical properties of the middle atmosphere to altitudes below 50 km. During the decline and activity minimum of the current solar cycle, we anticipate the occurence of similar

  1. Energy deposition and middle atmosphere electrodynamic response to a highly relativistic electron precipitation event

    NASA Technical Reports Server (NTRS)

    Goldberg, R. A.; Baker, D. N.; Herrero, F. A.; Mccarthy, S. P.; Twigg, P. A.; Croskey, C. L.; Hale, L. C.

    1994-01-01

    Rocket data have been used to evaluate the characteristics of precipitating relativistic electrons and their effects on the electrodynamic structure of the middle atmosphere. These data were obtained at Poker Flat, Alaska, on May 13 and 14, 1990, during a midday, highly relativistic electron (HRE) precipitation event. Solid state detectors were used to measure the electron fluxes and their energy spectra. An X ray scintillator was included on each flight to measure bremsstrahlung X rays produced by energetic electrons impacting on the upper atmosphere. However, these were found the be of negligible importance for this particular event. The energy deposition by the electrons has been determined from the flux measurements and compared with in situ measurements of the atmospheric electrical response. The electrodynamic measurements were obtained by the same rockets and additionally on May 13, with an accompanying rocket. The impact flux was highly irregular, containing short-lived bursts of relativistic electrons, mainly with energies below 0.5 MeV and with fluxes most enhanced between pitch angles of 0 deg - 20 deg. Although the geostationary counterpart of this measured event was considered to be of relatively low intensity and hardness, energy deposition peaked near 75 km with fluxes approaching an ion pair production rate in excess of 100/cu cm s. This exceeds peak fluxes in relativistic electron precipitation (REP) events as observed by us in numerous rocket soundings since 1976. Conductivity measurements from a blunt probe showed that negative electrical conductivities exceeded positive conductivities down to 50 km or lower, consistent with steady ionization by precipitating electrons above 1 MeV. These findings imply that the electrons from the outer radiation zone can modulate the electrical properties of the middle atmosphere to altitudes below 50 km. During the decline and activity minimum of the current solar cycle, we anticipate the occurence of similar

  2. Slow slip events in plate-rate laboratory experiments on samples from shallow regions of subduction megathrusts

    NASA Astrophysics Data System (ADS)

    Ikari, M.; Ito, Y.; Ujiie, K.; Kopf, A.

    2015-12-01

    It is now recognized that slow slip events on plate-boundary fault zones occur not only downdip of the seismogenic zone, but also updip within several km from the seafloor. These shallower events are advantageous because the fault material can be sampled by drilling, and in-situ conditions can be replicated in the laboratory. We report here on results of laboratory friction experiments investigating fault zone material sampled during Ocean Drilling Program and International Ocean Drilling Program expeditions to subduction zones in Japan and Costa Rica. We employ laboratory conditions of 7-16 MPa effective stress and ~20 °C simulating ~1-2.5 km burial depth. Additionally, we shear the samples at plate convergence rates of less than 10 cm/yr. When driven at plate convergence rates, friction perturbations analogous to slow slip events are sometimes observed. In plate-boundary fault zone samples from the Tohoku region at the Japan Trench, these events exhibit stress drops of 3-7% over several hours with a maximum slip rate of 10-25 cm/yr under 7 MPa effective normal stress. Increasing the effective normal stress to 16 kPa results in a corresponding increase in stress drop up to 15% and slip rates up to 57 cm/yr, consistent with critical stiffness theory which predicts that increasing effective normal stress decreases frictional stability. A sample from the plate boundary décollement from the Costa Rica margin exhibited similar slow slip behavior, with stress drops of 3-12% and maximum slip velocities up to 16 cm/yr. This sample is described as a hemipelagic clay, whereas a sample of nannofossil chalk from the same region did not exhibit such behavior. For the Nankai Trough offshore Japan, samples from the megasplay fault zone and décollement did not exhibit the slow slip events observed in the Japan Trench and Costa Rica samples. Analyses of velocity-stepping data from these tests indicate a propensity for velocity-weakening frictional behavior at slow rates

  3. Digitizing Standard & High Resolution High Frame Rate Video Camera Signals

    NASA Astrophysics Data System (ADS)

    Simmons, David M.

    1988-03-01

    The digitizing of an analog video camera signal requires special techniques to accurately sample the signal. Careful attention must be paid to both amplitude and timing considerations. Specifications exist which define amplitude and timing parame-ters of so called "standard" cameras. Recent advances in CCD technology have lead to the development of high resolution line scan and area cameras. Unfortunately these cameras do not con-form to any published standard. Hardware designed to digitize these "non-standard" cameras must have a flexible architecture to allow for each cameras' particular interface requirements.

  4. The role of dose rate in radiation cancer risk: evaluating the effect of dose rate at the molecular, cellular and tissue levels using key events in critical pathways following exposure to low LET radiation

    PubMed Central

    Brooks, Antone L.; Hoel, David G.; Preston, R. Julian

    2016-01-01

    Abstract Purpose: This review evaluates the role of dose rate on cell and molecular responses. It focuses on the influence of dose rate on key events in critical pathways in the development of cancer. This approach is similar to that used by the U.S. EPA and others to evaluate risk from chemicals. It provides a mechanistic method to account for the influence of the dose rate from low-LET radiation, especially in the low-dose region on cancer risk assessment. Molecular, cellular, and tissues changes are observed in many key events and change as a function of dose rate. The magnitude and direction of change can be used to help establish an appropriate dose rate effectiveness factor (DREF). Conclusions: Extensive data on key events suggest that exposure to low dose-rates are less effective in producing changes than high dose rates. Most of these data at the molecular and cellular level support a large (2–30) DREF. In addition, some evidence suggests that doses delivered at a low dose rate decrease damage to levels below that observed in the controls. However, there are some data human and mechanistic data that support a dose-rate effectiveness factor of 1. In summary, a review of the available molecular, cellular and tissue data indicates that not only is dose rate an important variable in understanding radiation risk but it also supports the selection of a DREF greater than one as currently recommended by ICRP (2007) and BEIR VII (NRC/NAS 2006). PMID:27266588

  5. Forecasting extreme wave events in moderate and high sea states

    NASA Astrophysics Data System (ADS)

    Magnusson, Anne Karin; Reistad, Magnar; Bitner-Gregersen, Elzbieta Maria

    2013-04-01

    Empirical studies on measurements have not yet come to conclusive relations between occurrence of rogue waves and - parameters which could be forecasted . Theoretical and tank experiments have demonstrated that high spectral peakedness and low spectral width combined (high Benjamin-Feir instability index, Onorato et al., 2006) give higher probability of rogue wave occurrence. Directional spread seems to reduce the probability of occurrence of rogue waves in these studies. Many years of experience with forecasting and discussions with people working in ocean environment indicate that rogue waves may as well occur in crossing seas. This was also indicated in a study in the Maxwave project (Toffoli et al., 2003) and the EXTREME SEAS project (Toffoli et al., 2011). We have here experimented with some indexes describing both high BFI and crossing seas and run the WAM model for some North Sea storm cases. Wave distributions measured at Ekofisk are analysed in the different cases. References • Onorato, M., Osborne, A., Serio, M., Cavaleri, L., Brandini, C., and Stansberg, C.: Extreme waves, modulational instability and second order theory: wave flume experiments on irregular waves,Europ. J. Mech. B/Fluids, 25, 586-601, 2006. • Toffoli, A., Lefevre, J.M., Monbaliu, J., Savina, H., and Bitner-Gregersen, E., "Freak Waves:Clues for Prediction in Ship Accidents?", Proc. ISOPE'2003 Conf. Hawai, USA, 2003. • Toffoli A., Bitner-Gregersen E. M., Osborne A. R., Serio M. Monbaliu J., Onorato M. (2011) Extreme Waves in Random Crossing Seas: Laboratory Experiments and Numerical Simulations. Geophys. Res. Lett., Vol. 38, L06605, 5 pp. doi: 10.1029/2011.

  6. HIGH-RATE FORMABILITY OF HIGH-STRENGTH ALUMINUM ALLOYS: A STUDY ON OBJECTIVITY OF MEASURED STRAIN AND STRAIN RATE

    SciTech Connect

    Upadhyay, Piyush; Rohatgi, Aashish; Stephens, Elizabeth V.; Davies, Richard W.; Catalini, David

    2015-02-18

    Al alloy AA7075 sheets were deformed at room temperature at strain-rates exceeding 1000 /s using the electrohydraulic forming (EHF) technique. A method that combines high speed imaging and digital image correlation technique, developed at Pacific Northwest National Laboratory, is used to investigate high strain rate deformation behavior of AA7075. For strain-rate sensitive materials, the ability to accurately model their high-rate deformation behavior is dependent upon the ability to accurately quantify the strain-rate that the material is subjected to. This work investigates the objectivity of software-calculated strain and strain rate by varying different parameters within commonly used commercially available digital image correlation software. Except for very close to the time of crack opening the calculated strain and strain rates are very consistent and independent of the adjustable parameters of the software.

  7. Miniature High Stability High Temperature Space Rated Blackbody Radiance Source

    NASA Astrophysics Data System (ADS)

    Jones, J. A.; Beswick, A. G.

    1987-09-01

    This paper presents the design and test performance of a conical cavity type blackbody radiance source that will meet the requirements of the Halogen Occultation Experiment (HALOE) on the NASA Upper Atmospheric Research Satellite program (UARS). Since a radiance source meeting the requirements of this experiment was unavailable in the commercial market, a development effort was undertaken by the HALOE Project. The blackbody radiance source operates in vacuum at 1300 K + 0.5 K over any 15-minute interval, uses less than 7.5 watts of power, maintains a 49°C outer case temperature, and fits within the 2.5 x 2.5 x 3.0 inch envelope allocated inside the HALOE instrument. Also, the unit operates in air, during ground testing of the HALOE instrument, where it uses 17 watts of power with an outer case temperature of 66°C. The thrust of this design effort was to minimize the heat losses, in order to keep the power usage under 7.5 watts, and to minimize the amount of silica in the materials. Silica in the presence of the platinum heater winding used in this design would cause the platinum to erode, changing the operating temperature set-point. The design required the development of fabrication techniques which would provide very small, close tolerance parts from extremely difficult-to-machine materials. Also, a space rated ceramic core and unique, low thermal conductance, ceramic-to-metal joint was developed, tested and incorporated in this design. The completed flight qualification hardware has undergone performance, environmental and life testing. The design configuration and test results are discussed in detail in this paper.

  8. Safety and efficacy of low fluence, high repetition rate versus high fluence, low repetition rate 810-nm diode laser for axillary hair removal in Chinese women.

    PubMed

    Li, Wenhai; Liu, Chengyi; Chen, Zhou; Cai, Lin; Zhou, Cheng; Xu, Qianxi; Li, Houmin; Zhang, Jianzhong

    2016-11-01

    High-fluence diode lasers with contact cooling have emerged as the gold standard to remove unwanted hair. Lowering the energy should result in less pain and could theoretically affect the efficacy of the therapy. To compare the safety and efficacy of a low fluence high repetition rate 810-nm diode laser to those of a high fluence, low repetition rate diode laser for permanent axillary hair removal in Chinese women. Ninety-two Chinese women received four axillae laser hair removal treatments at 4-week intervals using the low fluence, high repetition rate 810-nm diode laser in super hair removal (SHR) mode on one side and the high fluence, low repetition rate diode laser in hair removal (HR) mode on the other side. Hair counts were done at each follow-up visit and 6-month follow-up after the final laser treatment using a "Hi Quality Hair Analysis Program System"; the immediate pain score after each treatment session was recorded by a visual analog scale. The overall median reduction of hair was 90.2% with the 810-nm diode laser in SHR mode and 87% with the same laser in HR mode at 6-month follow-up. The median pain scores in SHR mode and in HR mode were 2.75 and 6.75, respectively. Low fluence, high repetition rate diode laser can efficiently remove unwanted hair but also significantly improve tolerability and reduce adverse events during the course of treatment.

  9. High-Strain-Rate behavior of Hydrated Cement Paste.

    DTIC Science & Technology

    1987-01-29

    bar and the transmitter bar are made from high yield- strength material, peak loads of 150,000 psi or 10 kbar are easily reached. Typical strain rates...was originally set up for testing very high yield- strength materials. Therefore, for use with cement paste samples, a series of new pressure bars -- 1...a. A a.5.. ~ A - a .- ~- . . . ~0 MML TR 87-12c HIGH -STRAIN-RATE BEHAVIOR OF HYDRATED CEMENT PASTE

  10. Ion Anisotropy and High-Energy Variability of Large Solar Particle Events: A Comparative Study

    NASA Technical Reports Server (NTRS)

    Tan, Lun C.; Reames, Donald V.; Ng, Chee K.

    2008-01-01

    We have made comparative studies of ion anisotropy and high-energy variability of solar energetic particle (SEP) events previously examined by the Solar, Heliospheric, and Interplanetary Environment (SHINE) Workshop campaign. We have found distinctly different characteristics of SEPs between two large "gradual" events having very similar solar progenitors (the 2002 April 21 and August 24 events). Since the scattering centers of SEPs are approximately frozen in the solar wind, we emphasize work in the solar-wind frame where SEPs tend to be isotropized, and small anisotropies are easier to detect. While in the August event no streaming reversal occurred, in the April event the field-aligned anisotropy of all heavy ions showed sign of streaming reversal. The difference in streaming reversal was consistent with the difference in the presence of the outer reflecting boundary. In the April event the magnetic mirror, which was located behind the interplanetary shock driven by the preceding coronal mass ejection (CME), could block the stream of SEPs, while in the August event SEPs escaped freely because of the absence of nearby boundary. The magnetic mirror was formed at the bottleneck of magnetic field lines draped around a flank of the preceding CME. In the previous SHINE event analysis the contrasting event durations and Fe/O ratios of the both events were explained as the interplay between shock geometry and seed population. Our new findings, however, indicate that event duration and time as well as spectral variation are also affected by the presence of a nearby reflecting boundary.

  11. A Nuclear Interaction Model for Understanding Results of Single Event Testing with High Energy Protons

    NASA Technical Reports Server (NTRS)

    Culpepper, William X.; ONeill, Pat; Nicholson, Leonard L.

    2000-01-01

    An internuclear cascade and evaporation model has been adapted to estimate the LET spectrum generated during testing with 200 MeV protons. The model-generated heavy ion LET spectrum is compared to the heavy ion LET spectrum seen on orbit. This comparison is the basis for predicting single event failure rates from heavy ions using results from a single proton test. Of equal importance, this spectra comparison also establishes an estimate of the risk of encountering a failure mode on orbit that was not detected during proton testing. Verification of the general results of the model is presented based on experiments, individual part test results, and flight data. Acceptance of this model and its estimate of remaining risk opens the hardware verification philosophy to the consideration of radiation testing with high energy protons at the board and box level instead of the more standard method of individual part testing with low energy heavy ions.

  12. Vacuum oscillations and excess of high energy solar neutrino events observed in Superkamiokande

    NASA Astrophysics Data System (ADS)

    Berezinsky, V.; Fiorentini, G.; Lissia, M.

    2000-01-01

    The excess of solar-neutrino events above 13 MeV that has been recently observed by Superkamiokande can be explained by the vacuum oscillation solution to the Solar Neutrino Problem (SNP). If the boron neutrino flux is 20% smaller than the standard solar model (SSM) prediction and the chlorine signal is assumed 30% (or 3.4σ) higher than the measured one, there exists a vacuum oscillation solution to SNP that reproduces both the observed spectrum of the recoil electrons, including the high energy distortion, and the other measured neutrino rates. The most distinct signature of this solution is a semi-annual seasonal variation of the 7Be neutrino flux with maximal amplitude. While the temporal series of the GALLEX and Homestake signals suggest that such a seasonal variation could be present, future detectors (BOREXINO, LENS and probably GNO) will be able to test it.

  13. Prolonged elevated heart rate is a risk factor for adverse cardiac events and poor outcome after subarachnoid hemorrhage.

    PubMed

    Schmidt, J Michael; Crimmins, Michael; Lantigua, Hector; Fernandez, Andres; Zammit, Chris; Falo, Cristina; Agarwal, Sachin; Claassen, Jan; Mayer, Stephan A

    2014-06-01

    Sympathetic nervous system hyperactivity is common after subarachnoid hemorrhage (SAH). We sought to determine whether uncontrolled prolonged heart rate elevation is a risk factor for adverse cardiopulmonary events and poor outcome after SAH. We prospectively studied 447 SAH patients between March 2006 and April 2012. Prior studies define prolonged elevated heart rate (PEHR) as heart rate >95 beats/min for >12 h. Major adverse cardiopulmonary events were documented according to the predefined criteria. Global outcome at 3 months was assessed with the modified Rankin Scale (mRS). 175 (39 %) patients experienced PEHR. Nonwhite race/ethnicity, admission Hunt-Hess grade ≥4, elevated APACHE-2 physiological subscore, and modified Fisher score were significant admission predictors of PEHR, whereas documented pre-hospital beta-blocker use was protective. After controlling for admission Hunt-Hess grade, Cox regression using time-lagged covariates revealed that PEHR onset in the previous 48 h was associated with an increased hazard for delayed cerebral ischemia, myocardial injury, and pulmonary edema. PEHR was associated with 3-month poor outcome (mRS 4-6) after controlling for known predictors. PEHR is associated with major adverse cardiopulmonary events and poor outcome after SAH. Further study is warranted to determine if early sympatholytic therapy targeted at sustained heart rate control can improve outcome after SAH.

  14. Sample Size Estimation for Negative Binomial Regression Comparing Rates of Recurrent Events with Unequal Follow-Up Time.

    PubMed

    Tang, Yongqiang

    2015-01-01

    A sample size formula is derived for negative binomial regression for the analysis of recurrent events, in which subjects can have unequal follow-up time. We obtain sharp lower and upper bounds on the required size, which is easy to compute. The upper bound is generally only slightly larger than the required size, and hence can be used to approximate the sample size. The lower and upper size bounds can be decomposed into two terms. The first term relies on the mean number of events in each group, and the second term depends on two factors that measure, respectively, the extent of between-subject variability in event rates, and follow-up time. Simulation studies are conducted to assess the performance of the proposed method. An application of our formulae to a multiple sclerosis trial is provided.

  15. Resting heart rate and measures of effort-related cardiac autonomic dysfunction predict cardiovascular events in asymptomatic type 2 diabetes.

    PubMed

    Zafrir, Barak; Azencot, Mali; Dobrecky-Mery, Idit; Lewis, Basil S; Flugelman, Moshe Y; Halon, David A

    2016-08-01

    Autonomic control of the cardiovascular system may be impaired in type 2 diabetes and is associated with increased morbidity and mortality. Parameters obtained during stress testing may reflect early stages of cardiac autonomic dysfunction and provide prognostic information in asymptomatic type 2 diabetes. We performed maximal exercise treadmill testing in 594 patients with type 2 diabetes without known coronary heart disease. The prognostic significance of physiological parameters associated with autonomic dysfunction was assessed, including chronotropic incompetence (<80% heart rate reserve), abnormal heart rate recovery at 1 minute <18 beats/minute, and resting tachycardia >100 beats/minute. Cox proportional hazards analysis was used to determine the association of exercise parameters with a composite outcome of all-cause mortality, myocardial infarction or stroke. Resting heart rate >100 beats/minute was observed in 18% of patients, chronotropic incompetence in 30% and heart rate recovery at 1 minute <18 beats/minute in 35%. Over 79 ± 16 months, there were 72 (12%) events. Each parameter was significantly associated with event risk in an adjusted multivariate analysis: chronotropic incompetence (hazard ratio 1.89, 95% confidence interval 1.18-3.01; P = 0.008), resting heart rate ≥100 beats/minute (hazard ratio 1.97, 95% confidence interval 1.19-3.26; P = 0.008) and heart rate recovery at 1 minute <18 beats (hazard ratio 1.77, 95% confidence interval 1.12-2.81; P = 0.015). A progressive relationship between the number of abnormal parameters and event risk was observed (log rank P < 0.001). Chronotropic incompetence, resting tachycardia and reduced heart rate recovery are independently and additively associated with long-term mortality, myocardial infarction or stroke in type 2 diabetes without known coronary heart disease. © The European Society of Cardiology 2015.

  16. A change in coral extension rates and stable isotopes after El Niño-induced coral bleaching and regional stress events

    PubMed Central

    Hetzinger, S.; Pfeiffer, M.; Dullo, W.-Chr.; Zinke, J.; Garbe-Schönberg, D.

    2016-01-01

    Coral reefs are biologically diverse ecosystems threatened with effective collapse under rapid climate change, in particular by recent increases in ocean temperatures. Coral bleaching has occurred during major El Niño warming events, at times leading to the die-off of entire coral reefs. Here we present records of stable isotopic composition, Sr/Ca ratios and extension rate (1940–2004) in coral aragonite from a northern Venezuelan site, where reefs were strongly impacted by bleaching following the 1997–98 El Niño. We assess the impact of past warming events on coral extension rates and geochemical proxies. A marked decrease in coral (Pseudodiploria strigosa) extension rates coincides with a baseline shift to more negative values in oxygen and carbon isotopic composition after 1997–98, while a neighboring coral (Siderastrea siderea) recovered to pre-bleaching extension rates simultaneously. However, other stressors, besides high temperature, might also have influenced coral physiology and geochemistry. Coastal Venezuelan reefs were exposed to a series of extreme environmental fluctuations since the mid-1990s, i.e. upwelling, extreme rainfall and sediment input from landslides. This work provides important new data on the potential impacts of multiple regional stress events on coral isotopic compositions and raises questions about the long-term influence on coral-based paleoclimate reconstructions. PMID:27619506

  17. A change in coral extension rates and stable isotopes after El Niño-induced coral bleaching and regional stress events.

    PubMed

    Hetzinger, S; Pfeiffer, M; Dullo, W-Chr; Zinke, J; Garbe-Schönberg, D

    2016-09-13

    Coral reefs are biologically diverse ecosystems threatened with effective collapse under rapid climate change, in particular by recent increases in ocean temperatures. Coral bleaching has occurred during major El Niño warming events, at times leading to the die-off of entire coral reefs. Here we present records of stable isotopic composition, Sr/Ca ratios and extension rate (1940-2004) in coral aragonite from a northern Venezuelan site, where reefs were strongly impacted by bleaching following the 1997-98 El Niño. We assess the impact of past warming events on coral extension rates and geochemical proxies. A marked decrease in coral (Pseudodiploria strigosa) extension rates coincides with a baseline shift to more negative values in oxygen and carbon isotopic composition after 1997-98, while a neighboring coral (Siderastrea siderea) recovered to pre-bleaching extension rates simultaneously. However, other stressors, besides high temperature, might also have influenced coral physiology and geochemistry. Coastal Venezuelan reefs were exposed to a series of extreme environmental fluctuations since the mid-1990s, i.e. upwelling, extreme rainfall and sediment input from landslides. This work provides important new data on the potential impacts of multiple regional stress events on coral isotopic compositions and raises questions about the long-term influence on coral-based paleoclimate reconstructions.

  18. A change in coral extension rates and stable isotopes after El Niño-induced coral bleaching and regional stress events

    NASA Astrophysics Data System (ADS)

    Hetzinger, S.; Pfeiffer, M.; Dullo, W.-Chr.; Zinke, J.; Garbe-Schönberg, D.

    2016-09-01

    Coral reefs are biologically diverse ecosystems threatened with effective collapse under rapid climate change, in particular by recent increases in ocean temperatures. Coral bleaching has occurred during major El Niño warming events, at times leading to the die-off of entire coral reefs. Here we present records of stable isotopic composition, Sr/Ca ratios and extension rate (1940-2004) in coral aragonite from a northern Venezuelan site, where reefs were strongly impacted by bleaching following the 1997-98 El Niño. We assess the impact of past warming events on coral extension rates and geochemical proxies. A marked decrease in coral (Pseudodiploria strigosa) extension rates coincides with a baseline shift to more negative values in oxygen and carbon isotopic composition after 1997-98, while a neighboring coral (Siderastrea siderea) recovered to pre-bleaching extension rates simultaneously. However, other stressors, besides high temperature, might also have influenced coral physiology and geochemistry. Coastal Venezuelan reefs were exposed to a series of extreme environmental fluctuations since the mid-1990s, i.e. upwelling, extreme rainfall and sediment input from landslides. This work provides important new data on the potential impacts of multiple regional stress events on coral isotopic compositions and raises questions about the long-term influence on coral-based paleoclimate reconstructions.

  19. Investigation of High-Pressure Hydraulic Vortex Rate Sensor

    DTIC Science & Technology

    stability - augmentation system . The feasibility of low-pressure fluid stabilization systems was demonstrated. The primary component that requires development for implementation in a high pressure system is the vortex rate sensor. The high-pressure hydraulic vortex rate sensor has an on-board built-in supply of hydraulic fluid which is used in the primary hydro-mechanical flight control of the vehicle. A small amount of hydraulic fluid under high pressure can be diverted from the main system to the vortex rate sensor, used to perform a sensing function, and

  20. Quantum data locking for high-rate private communication

    NASA Astrophysics Data System (ADS)

    Lupo, Cosmo; Lloyd, Seth

    2015-03-01

    We show that, if the accessible information is used as a security quantifier, quantum channels with a certain symmetry can convey private messages at a tremendously high rate, as high as less than one bit below the rate of non-private classical communication. This result is obtained by exploiting the quantum data locking effect. The price to pay to achieve such a high private communication rate is that accessible information security is in general not composable. However, composable security holds against an eavesdropper who is forced to measure her share of the quantum system within a finite time after she gets it.

  1. Flare vs. Shock Acceleration of High-energy Protons in Solar Energetic Particle Events

    NASA Astrophysics Data System (ADS)

    Cliver, E. W.

    2016-12-01

    Recent studies have presented evidence for a significant to dominant role for a flare-resident acceleration process for high-energy protons in large (“gradual”) solar energetic particle (SEP) events, contrary to the more generally held view that such protons are primarily accelerated at shock waves driven by coronal mass ejections (CMEs). The new support for this flare-centric view is provided by correlations between the sizes of X-ray and/or microwave bursts and associated SEP events. For one such study that considered >100 MeV proton events, we present evidence based on CME speeds and widths, shock associations, and electron-to-proton ratios that indicates that events omitted from that investigation’s analysis should have been included. Inclusion of these outlying events reverses the study’s qualitative result and supports shock acceleration of >100 MeV protons. Examination of the ratios of 0.5 MeV electron intensities to >100 MeV proton intensities for the Grechnev et al. event sample provides additional support for shock acceleration of high-energy protons. Simply scaling up a classic “impulsive” SEP event to produce a large >100 MeV proton event implies the existence of prompt 0.5 MeV electron events that are approximately two orders of magnitude larger than are observed. While classic “impulsive” SEP events attributed to flares have high electron-to-proton ratios (≳5 × 105) due to a near absence of >100 MeV protons, large poorly connected (≥W120) gradual SEP events, attributed to widespread shock acceleration, have electron-to-proton ratios of ˜2 × 103, similar to those of comparably sized well-connected (W20-W90) SEP events.

  2. Slip Rates, Recurrence Intervals and Earthquake Event Magnitudes for the southern Black Mountains Fault Zone, southern Death Valley, California

    NASA Astrophysics Data System (ADS)

    Fronterhouse Sohn, M.; Knott, J. R.; Bowman, D. D.

    2005-12-01

    The normal-oblique Black Mountain Fault zone (BMFZ) is part of the Death Valley fault system. Strong ground-motion generated by earthquakes on the BMFZ poses a serious threat to the Las Vegas, NV area (pop. ~1,428,690), the Death Valley National Park (max. pop. ~20,000) and Pahrump, NV (pop. 30,000). Fault scarps offset Holocene alluvial-fan deposits along most of the 80-km length of the BMFZ. However, slip rates, recurrence intervals, and event magnitudes for the BMFZ are poorly constrained due to a lack of age control. Also, Holocene scarp heights along the BMFZ range from <1 m to >6 m suggesting that geomorphic sections have different earthquake histories. Along the southernmost section, the BMFZ steps basinward preserving three post-late Pleistocene fault scarps. Surveys completed with a total station theodolite show scarp heights of 5.5, 5.0 and 2 meters offsetting the late Pleistocene, early to middle Holocene, to middle-late Holocene surfaces, respectively. Regression plots of vertical offset versus maximum scarp angle suggest event ages of <10 - 2 ka with a post-late Pleistocene slip rate of 0.1mm/yr to 0.3 mm/yr and recurrence of <3300 years/event. Regression equations for the estimated geomorphically constrained rupture length of the southernmost section and surveyed event displacements provides estimated moment magnitudes (Mw) between 6.6 and 7.3 for the BMFZ.

  3. Weighted Hurdle Regression Method for Joint Modeling of Cardiovascular Events Likelihood and Rate in the U.S. Dialysis Population

    PubMed Central

    Şentürk, Damla; Dalrymple, Lorien S.; Mu, Yi; Nguyen, Danh V.

    2014-01-01

    SUMMARY We propose a new weighted hurdle regression method for modeling count data, with particular interest in modeling cardiovascular events in patients on dialysis. Cardiovascular disease remains one of the leading causes of hospitalization and death in this population. Our aim is to jointly model the relationship/association between covariates and (a) the probability of cardiovascular events, a binary process and (b) the rate of events once the realization is positive - when the ‘hurdle’ is crossed - using a zero-truncated Poisson distribution. When the observation period or follow-up time, from the start of dialysis, varies among individuals the estimated probability of positive cardiovascular events during the study period will be biased. Furthermore, when the model contains covariates, then the estimated relationship between the covariates and the probability of cardiovascular events will also be biased. These challenges are addressed with the proposed weighted hurdle regression method. Estimation for the weighted hurdle regression model is a weighted likelihood approach, where standard maximum likelihood estimation can be utilized. The method is illustrated with data from the United States Renal Data System. Simulation studies show the ability of proposed method to successfully adjust for differential follow-up times and incorporate the effects of covariates in the weighting. PMID:24930810

  4. Weighted hurdle regression method for joint modeling of cardiovascular events likelihood and rate in the US dialysis population.

    PubMed

    Sentürk, Damla; Dalrymple, Lorien S; Mu, Yi; Nguyen, Danh V

    2014-11-10

    We propose a new weighted hurdle regression method for modeling count data, with particular interest in modeling cardiovascular events in patients on dialysis. Cardiovascular disease remains one of the leading causes of hospitalization and death in this population. Our aim is to jointly model the relationship/association between covariates and (i) the probability of cardiovascular events, a binary process, and (ii) the rate of events once the realization is positive-when the 'hurdle' is crossed-using a zero-truncated Poisson distribution. When the observation period or follow-up time, from the start of dialysis, varies among individuals, the estimated probability of positive cardiovascular events during the study period will be biased. Furthermore, when the model contains covariates, then the estimated relationship between the covariates and the probability of cardiovascular events will also be biased. These challenges are addressed with the proposed weighted hurdle regression method. Estimation for the weighted hurdle regression model is a weighted likelihood approach, where standard maximum likelihood estimation can be utilized. The method is illustrated with data from the United States Renal Data System. Simulation studies show the ability of proposed method to successfully adjust for differential follow-up times and incorporate the effects of covariates in the weighting.

  5. Correlation between Coulomb Stress Rate Change imparted by the Slow Slip Events and Seismic Rate Change in Lower Cook Inlet of the Alaska-Aleutian Subduction Zone

    NASA Astrophysics Data System (ADS)

    Li, S.; Freymueller, J.; Wang, J.; Ruppert, N. A.

    2016-12-01

    We identified two long-term slow slip events (SSEs) in Lower Cook Inlet, southcentral Alaska (1995.0-2004.8 and 2009.85-2011.81) by inverting the GPS site velocities (Li et al. 2016). The earlier SSE lasted at least 9 years (observations in that area began in 1995) with Mw 7.8 and average slip magnitude as 82 mm/yr. The latter SSE had almost the same area as the earlier one, which is within 40-60 km depth range, and a duration of 2 years with Mw 7.2 and average slip magnitude as 91 mm/yr. We resolved the Coulomb stress rate changes on receiver faults determined from focal mechanism solutions for over 2000 earthquakes that previously occurred in the crust and, in the subducting slab. The crustal earthquakes exhibit a variety of faulting types across the region. The slab events are mainly dominated by strike-slip and normal faulting in the shallower depth range (<100 km) , and strike-slip and thrust faulting at greater depths. Our results showed that the first SSE triggered earthquakes right above the downdip end of slowly slipping region while the second SSE caused smaller Coulomb stress rates change and did not significantly change the seismicity rate for receiver faults in the crust. For receiver faults in the slab, both SSEs triggered earthquakes below the SSE areas within the subducting slab. These all support the triggering hypothesis: the regions where the Coulomb stress rate changes increased due to the SSEs also experienced an increased seismicity rate during the SSE period. We will implement a rate/state algorithm that incorporates the Coulomb stress rate change transferred by the two SSEs and seek to explore how SSEs redistribute stress. It will provide us better insight into quantifying the possibilities of potential large and destructive earthquakes caused by the increasing potential hazard of the SSEs.

  6. Event-Associated Oxygen Consumption Rate Increases ca. Five-Fold When Interictal Activity Transforms into Seizure-Like Events In Vitro.

    PubMed

    Schoknecht, Karl; Berndt, Nikolaus; Rösner, Jörg; Heinemann, Uwe; Dreier, Jens P; Kovács, Richard; Friedman, Alon; Liotta, Agustin

    2017-09-07

    Neuronal injury due to seizures may result from a mismatch of energy demand and adenosine triphosphate (ATP) synthesis. However, ATP demand and oxygen consumption rates have not been accurately determined, yet, for different patterns of epileptic activity, such as interictal and ictal events. We studied interictal-like and seizure-like epileptiform activity induced by the GABAA antagonist bicuculline alone, and with co-application of the M-current blocker XE-991, in rat hippocampal slices. Metabolic changes were investigated based on recording partial oxygen pressure, extracellular potassium concentration, and intracellular flavine adenine dinucleotide (FAD) redox potential. Recorded data were used to calculate oxygen consumption and relative ATP consumption rates, cellular ATP depletion, and changes in FAD/FADH₂ ratio by applying a reactive-diffusion and a two compartment metabolic model. Oxygen-consumption rates were ca. five times higher during seizure activity than interictal activity. Additionally, ATP consumption was higher during seizure activity (~94% above control) than interictal activity (~15% above control). Modeling of FAD transients based on partial pressure of oxygen recordings confirmed increased energy demand during both seizure and interictal activity and predicted actual FAD autofluorescence recordings, thereby validating the model. Quantifying metabolic alterations during epileptiform activity has translational relevance as it may help to understand the contribution of energy supply and demand mismatches to seizure-induced injury.

  7. A Survey of Appalachian Middle & High School Teacher Perceptions of Controversial Current Events Instruction

    ERIC Educational Resources Information Center

    Sharp, Kimberlee A.

    2009-01-01

    This study examined the perspectives of a sample of Appalachian middle and high school social studies teachers regarding the teaching of controversial current events. Specifically, the survey ascertained the teachers' familiarity with school district administrative policies regarding the teaching of controversial current events, their perceptions…

  8. The Event-Related Low-Frequency Activity of Highly and Average Intelligent Children

    ERIC Educational Resources Information Center

    Liu, Tongran; Shi, Jiannong; Zhao, Daheng; Yang, Jie

    2008-01-01

    Using time-frequency analysis techniques to investigate the event-related low-frequency (delta: 0.5-4 Hz; theta: 4-8 Hz) activity of auditory event-related potentials (ERPs) data of highly and average intelligent children, 18 intellectually gifted children, and 18 intellectually average children participated the present study. Present findings…

  9. The Event-Related Low-Frequency Activity of Highly and Average Intelligent Children

    ERIC Educational Resources Information Center

    Liu, Tongran; Shi, Jiannong; Zhao, Daheng; Yang, Jie

    2008-01-01

    Using time-frequency analysis techniques to investigate the event-related low-frequency (delta: 0.5-4 Hz; theta: 4-8 Hz) activity of auditory event-related potentials (ERPs) data of highly and average intelligent children, 18 intellectually gifted children, and 18 intellectually average children participated the present study. Present findings…

  10. Cultural Terms for Communication Events among Some American High School Adolescents.

    ERIC Educational Resources Information Center

    Baxter, Leslie A.; Goldsmith, Daena

    1990-01-01

    Examines the natural language descriptions employed by American high school adolescents in talking about the kinds of communication events they experience in everyday life. Finds that adolescents describe communication events through use of setting, participant, speech act, and purpose marker terms. Differentiates nine basic clusters of…

  11. Turbulence at high resolution: intense events in dissipation, enstrophy and acceleration

    NASA Astrophysics Data System (ADS)

    Yeung, P. K.; Zhai, X. M.; Sreenivasan, K. R.

    2014-11-01

    Access to the Blue Waters supercomputer under the NSF Track 1 Petascale Resource Allocations program has allowed us to conduct an 81923 simulation of forced isotropic turbulence, with Taylor-scale Reynolds number close to 1300, and grid spacing at about 1.5 Kolmogorov scales. Extreme fluctuations in dissipation and enstrophy (over 10,000 times the mean) are observed, and found to scale similarly and occur together. Conditional sampling based on both dissipation and enstrophy shows that such extreme events in these variables are directly associated with strong intermittency in the fluid particle acceleration, which reaches values well beyond 100 standard deviations. An attempt is made to characterize in detail the formation of events of intense dissipation and enstrophy, including the transport, production and dissipation terms in the dissipation and enstrophy transport equations, as well as the nature of local flow conditions in principal strain-rate axes. Statistics of dissipation and enstrophy averaged over 3D sub-domains of linear size in the inertial range are also available. Both high Reynolds number and good small-scale resolution are important factors in these results. Supported by NSF Grant ACI-1036170.

  12. Uncovering high-strain rate protection mechanism in nacre.

    PubMed

    Huang, Zaiwang; Li, Haoze; Pan, Zhiliang; Wei, Qiuming; Chao, Yuh J; Li, Xiaodong

    2011-01-01

    Under high-strain-rate compression (strain rate approximately 10(3) s(-1)), nacre (mother-of-pearl) exhibits surprisingly high fracture strength vis-à-vis under quasi-static loading (strain rate 10(-3) s(-1)). Nevertheless, the underlying mechanism responsible for such sharply different behaviors in these two loading modes remains completely unknown. Here we report a new deformation mechanism, adopted by nacre, the best-ever natural armor material, to protect itself against predatory penetrating impacts. It involves the emission of partial dislocations and the onset of deformation twinning that operate in a well-concerted manner to contribute to the increased high-strain-rate fracture strength of nacre. Our findings unveil that Mother Nature delicately uses an ingenious strain-rate-dependent stiffening mechanism with a purpose to fight against foreign attacks. These findings should serve as critical design guidelines for developing engineered body armor materials.

  13. Uncovering high-strain rate protection mechanism in nacre

    PubMed Central

    Huang, Zaiwang; Li, Haoze; Pan, Zhiliang; Wei, Qiuming; Chao, Yuh J.; Li, Xiaodong

    2011-01-01

    Under high-strain-rate compression (strain rate ∼103 s−1), nacre (mother-of-pearl) exhibits surprisingly high fracture strength vis-à-vis under quasi-static loading (strain rate 10−3 s−1). Nevertheless, the underlying mechanism responsible for such sharply different behaviors in these two loading modes remains completely unknown. Here we report a new deformation mechanism, adopted by nacre, the best-ever natural armor material, to protect itself against predatory penetrating impacts. It involves the emission of partial dislocations and the onset of deformation twinning that operate in a well-concerted manner to contribute to the increased high-strain-rate fracture strength of nacre. Our findings unveil that Mother Nature delicately uses an ingenious strain-rate-dependent stiffening mechanism with a purpose to fight against foreign attacks. These findings should serve as critical design guidelines for developing engineered body armor materials. PMID:22355664

  14. Uncovering high-strain rate protection mechanism in nacre

    NASA Astrophysics Data System (ADS)

    Huang, Zaiwang; Li, Haoze; Pan, Zhiliang; Wei, Qiuming; Chao, Yuh J.; Li, Xiaodong

    2011-11-01

    Under high-strain-rate compression (strain rate ~103 s-1), nacre (mother-of-pearl) exhibits surprisingly high fracture strength vis-à-vis under quasi-static loading (strain rate 10-3 s-1). Nevertheless, the underlying mechanism responsible for such sharply different behaviors in these two loading modes remains completely unknown. Here we report a new deformation mechanism, adopted by nacre, the best-ever natural armor material, to protect itself against predatory penetrating impacts. It involves the emission of partial dislocations and the onset of deformation twinning that operate in a well-concerted manner to contribute to the increased high-strain-rate fracture strength of nacre. Our findings unveil that Mother Nature delicately uses an ingenious strain-rate-dependent stiffening mechanism with a purpose to fight against foreign attacks. These findings should serve as critical design guidelines for developing engineered body armor materials.

  15. Quantifying the Rate of Surface Soil Drying Following Precipitation Events Using PBO H2o Soil Moisture Time Series

    NASA Astrophysics Data System (ADS)

    Prue, A. M.

    2014-12-01

    Surface soil moisture affects latent and sensible heat fluxes, as well as setting the top boundary condition for water redistribution within the soil column. The fluctuations in surface soil moisture have been described in numerous modeling studies, but characterization based on measurements is lacking. We use a new soil moisture dataset based on reflected GPS signals to provide some constraints on rates of surface soil drying after a rain event. The soil moisture time series used in this study are derived from GPS data collected at NSF's EarthScope Plate Boundary Observatory (PBO) sites. The University of Colorado Boulder's PBO H2O project estimates daily near-surface soil moisture (approximately 0-5 cm) from the interference pattern between the direct and ground-reflected GPS signals. The sensing footprint is ~1000 m2, and thus intermediate in scale between in situ and remotely sensed observations. Twelve sites from this network of more than 100 were used in this study. To characterize the rate of soil drying, we fit exponential curves to daily soil moisture observations following ten isolated rainfall events at each site. Event sizes varied from 5 to 40 mm and were followed by 17 days without rain. The decay model fits the data quite well, with r2 values exceeding 0.85 in nearly all cases. For 95% of the events studied, the exponential decay constant (e-folding time) fell between 2 and 6 days. Precipitation amount is not correlated with drydown rates. Instead, the rate of soil drying is well-correlated with air temperature: the exponential constant decreases by 0.1 days per degree Celsius. We are currently investigating how other factors, such as soil type and vegetation, influence soil drying. This study highlights the utility of the PBO H2O soil moisture product. Surface soil moisture changes rapidly, and thus the dynamics of surface soil moisture cannot be accurately characterized using datasets based on less than daily measurements.

  16. Laser nanoablation of diamond surface at high pulse repetition rates

    NASA Astrophysics Data System (ADS)

    Kononenko, V. V.; Gololobov, V. M.; Pashinin, V. P.; Konov, V. I.

    2016-10-01

    The chemical etching of the surface of a natural diamond single crystal irradiated by subpicosecond laser pulses with a high repetition rate (f ≤slant 500 {\\text{kHz}}) in air is experimentally investigated. The irradiation has been performed by the second-harmonic (515 {\\text{nm}}) radiation of a disk Yb : YAG laser. Dependences of the diamond surface etch rate on the laser energy density and pulse repetition rate are obtained.

  17. Search for anomalous production of events with a high energy lepton and photon at the Tevatron

    SciTech Connect

    Loginov, Andrey Borisovich

    2006-01-01

    We present results of a search for the anomalous production of events containing a high-transverse momentum charged lepton (ℓ, either e or μ) and photon (γ), accompanied by missing transverse energy (ET), and/or additional leptons and photons, and jets (X). We use the same kinematic selection criteria as in a previous CDF search, but with a substantially larger data set, 305 pb-1, a p$\\bar{p}$ collision energy of 1.96 TeV, and the upgraded CDF II detector. We find 42 ℓγET events versus a standard model expectation of 37.3 ± 5.4 events. The level of excess observed in Run I, 16 events with an expectation of 7.6 ± 0.7 events (corresponding to a 2.7 σ effect), is not supported by the new data. In the signature of ℓℓγ + X we observe 31 events versus an expectation of 23.0 ± 2.7 events. In this sample we find no events with an extra photon or ET and so find no events like the one eeγγ ET event observed in Run I.

  18. Putative extremely high rate of proteome innovation in lancelets might be explained by high rate of gene prediction errors

    PubMed Central

    Bányai, László; Patthy, László

    2016-01-01

    A recent analysis of the genomes of Chinese and Florida lancelets has concluded that the rate of creation of novel protein domain combinations is orders of magnitude greater in lancelets than in other metazoa and it was suggested that continuous activity of transposable elements in lancelets is responsible for this increased rate of protein innovation. Since morphologically Chinese and Florida lancelets are highly conserved, this finding would contradict the observation that high rates of protein innovation are usually associated with major evolutionary innovations. Here we show that the conclusion that the rate of proteome innovation is exceptionally high in lancelets may be unjustified: the differences observed in domain architectures of orthologous proteins of different amphioxus species probably reflect high rates of gene prediction errors rather than true innovation. PMID:27476717

  19. Putative extremely high rate of proteome innovation in lancelets might be explained by high rate of gene prediction errors.

    PubMed

    Bányai, László; Patthy, László

    2016-08-01

    A recent analysis of the genomes of Chinese and Florida lancelets has concluded that the rate of creation of novel protein domain combinations is orders of magnitude greater in lancelets than in other metazoa and it was suggested that continuous activity of transposable elements in lancelets is responsible for this increased rate of protein innovation. Since morphologically Chinese and Florida lancelets are highly conserved, this finding would contradict the observation that high rates of protein innovation are usually associated with major evolutionary innovations. Here we show that the conclusion that the rate of proteome innovation is exceptionally high in lancelets may be unjustified: the differences observed in domain architectures of orthologous proteins of different amphioxus species probably reflect high rates of gene prediction errors rather than true innovation.

  20. Rural and Urban High School Dropout Rates: Are They Different?

    ERIC Educational Resources Information Center

    Jordan, Jeffrey L.; Kostandini, Genti; Mykerezi, Elton

    2012-01-01

    This study estimates the high school dropout rate in rural and urban areas, the determinants of dropping out, and whether the differences in graduation rates have changed over time. We use geocoded data from two nationally representative panel household surveys (NLSY 97 and NLSY 79) and a novel methodology that corrects for biases in graduation…

  1. How Did Successful High Schools Improve Their Graduation Rates?

    ERIC Educational Resources Information Center

    Robertson, Janna Siegel; Smith, Robert W.; Rinka, Jason

    2016-01-01

    The researchers surveyed 23 North Carolina high schools that had markedly improved their graduation rates over the past five years. The administrators reported on the dropout prevention practices and programs to which they attributed their improved graduation rates. The majority of schools reported policy changes, especially with suspension. The…

  2. High School Graduation Rates in the United States. Revised.

    ERIC Educational Resources Information Center

    Greene, Jay P.

    This report presents public high school graduation rates for all students and for African Americans, Latinos, and white sub-groups. Rates are reported for each state, for each of the 50 largest school districts, and for a few other districts of interest. The state and district numbers are also reported separately for African Americans, Latinos,…

  3. Retrospective Analysis of Recent Flood Events With Persistent High Surface Runoff From Hydrological Modelling

    NASA Astrophysics Data System (ADS)

    Joshi, S.; Hakeem, K. Abdul; Raju, P. V.; Rao, V. V.; Yadav, A.; Diwakar, P. G.; Dadhwal, V. K.

    2014-11-01

    /locations with probable flooding conditions. These thresholds were refined through iterative process by comparing with satellite data derived flood maps of 2013 and 2014 monsoon season over India. India encountered many cyclonic flood events during Oct-Dec 2013, among which Phailin, Lehar, and Madi were rated to be very severe cyclonic storm. The path and intensity of these cyclonic events was very well captured by the model and areas were marked with persistent coverage of high runoff risk/flooded area. These thresholds were used to monitor floods in Jammu Kashmir during 4-5 Sep and Odisha during 8-9 Aug, 2014. The analysis indicated the need to vary the thresholds across space considering the terrain and geographical conditions. With respect to this a sub-basin wise study was made based on terrain characteristics (slope, elevation) using Aster DEM. It was found that basins with higher elevation represent higher thresholds as compared to basins with lesser elevation. The results show very promising correlation with the satellite derived flood maps. Further refinement and optimization of thresholds, varying them spatially accounting for topographic/terrain conditions, would lead to estimation of high runoff/flood risk areas for both riverine and drainage congested areas. Use of weather forecast data (NCMWRF, (GEFS/R)), etc. would enhance the scope to develop early warning systems.

  4. A rate-dependent Hosford-Coulomb model for predicting ductile fracture at high strain rates

    NASA Astrophysics Data System (ADS)

    Marcadet, Stephane J.; Roth, Christian C.; Erice, Borja; Mohr, Dirk

    2015-09-01

    The Hosford-Coulomb model incorporates the important effect of the Lode angle parameter in addition to the stress triaxiality to predict the initiation of ductile fracture. A strain-rate dependent extension of the Hosford-Coulomb model is presented to describe the results from low, intermediate and high strain rate fracture experiments on advanced high strength steels (DP590 and TRIP780). The model predictions agree well with the experimental observation of an increase in ductility as function of strain rate for stress states ranging from uniaxial to equi-biaxial tension.

  5. High-strain rate testing of HMX-based explosive

    NASA Astrophysics Data System (ADS)

    John, Henry J.; Alamo, Mike F.

    2000-04-01

    A split Hopkinson pressure bar (SHPB) was used to measure the mechanical behavior of Navy explosive PBXC-129 (a high-solids-loaded explosive material) with strain rates up to ˜3500 s-1. The PBXC-129's high-strain response is typical of other explosive and propellant behavior. At higher strain rates, the PBXC-129 shows significant stiffening with a possible reaction. Stress-strain curves and material properties for PBXC-129 are presented in this paper.

  6. Efficient ARQ scheme for high error rate channels

    NASA Astrophysics Data System (ADS)

    Moeneclaey, M.; Bruneel, H.

    1984-11-01

    A continuous error detection and retransmission (ARQ) protocol which preserves the order of the data block is presented. Data blocks are retransmitted continuously until a positive acknowledgement is received. The next block is then transmitted. It is shown that in high error rate conditions, i.e., the probability of message error is greater than 0.5, the scheme is more efficient than go-back-N and selective repeat schemes. The high error rates increase with the length of propagation delays.

  7. Identifying High-Rate Flows Based on Sequential Sampling

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Fang, Binxing; Luo, Hao

    We consider the problem of fast identification of high-rate flows in backbone links with possibly millions of flows. Accurate identification of high-rate flows is important for active queue management, traffic measurement and network security such as detection of distributed denial of service attacks. It is difficult to directly identify high-rate flows in backbone links because tracking the possible millions of flows needs correspondingly large high speed memories. To reduce the measurement overhead, the deterministic 1-out-of-k sampling technique is adopted which is also implemented in Cisco routers (NetFlow). Ideally, a high-rate flow identification method should have short identification time, low memory cost and processing cost. Most importantly, it should be able to specify the identification accuracy. We develop two such methods. The first method is based on fixed sample size test (FSST) which is able to identify high-rate flows with user-specified identification accuracy. However, since FSST has to record every sampled flow during the measurement period, it is not memory efficient. Therefore the second novel method based on truncated sequential probability ratio test (TSPRT) is proposed. Through sequential sampling, TSPRT is able to remove the low-rate flows and identify the high-rate flows at the early stage which can reduce the memory cost and identification time respectively. According to the way to determine the parameters in TSPRT, two versions of TSPRT are proposed: TSPRT-M which is suitable when low memory cost is preferred and TSPRT-T which is suitable when short identification time is preferred. The experimental results show that TSPRT requires less memory and identification time in identifying high-rate flows while satisfying the accuracy requirement as compared to previously proposed methods.

  8. Quantum Communication with a High-Rate Entangled Photon Source

    NASA Technical Reports Server (NTRS)

    Wilson, Nathaniel C.; Chaffee, Dalton W.; Lekki, John D.; Wilson, Jeffrey D.

    2016-01-01

    A high generation rate photon-pair source using a dual element periodically-poled potassium titanyl phosphate (PP KTP) waveguide is described. The photon-pair source features a high pair generation rate, a compact power-efficient package, and continuous wave (CW) or pulsed operation. Characterization and test results are presented. Details and preliminary results of a laboratory free-space QKD experiment with the B92 protocol are also presented.

  9. Dynamic tensile fracture of mortar at ultra-high strain-rates

    NASA Astrophysics Data System (ADS)

    Erzar, B.; Buzaud, E.; Chanal, P.-Y.

    2013-12-01

    During the lifetime of a structure, concrete and mortar may be exposed to highly dynamic loadings, such as impact or explosion. The dynamic fracture at high loading rates needs to be well understood to allow an accurate modeling of this kind of event. In this work, a pulsed-power generator has been employed to conduct spalling tests on mortar samples at strain-rates ranging from 2 × 104 to 4 × 104 s-1. The ramp loading allowed identifying the strain-rate anytime during the test. A power law has been proposed to fit properly the rate-sensitivity of tensile strength of this cementitious material over a wide range of strain-rate. Moreover, a specimen has been recovered damaged but unbroken. Micro-computed tomography has been employed to study the characteristics of the damage pattern provoked by the dynamic tensile loading.

  10. Gait event detection on level ground and incline walking using a rate gyroscope.

    PubMed

    Catalfamo, Paola; Ghoussayni, Salim; Ewins, David

    2010-01-01

    Gyroscopes have been proposed as sensors for ambulatory gait analysis and functional electrical stimulation systems. Accurate determination of the Initial Contact of the foot with the floor (IC) and the final contact or Foot Off (FO) on different terrains is important. This paper describes the evaluation of a gyroscope placed on the shank for determination of IC and FO in subjects walking outdoors on level ground, and up and down an incline. Performance was compared with a reference pressure measurement system. The mean difference between the gyroscope and the reference was less than -25 ms for IC and less than 75 ms for FO for all terrains. Detection success was over 98%. These results provide preliminary evidence supporting the use of the gyroscope for gait event detection on inclines as well as level walking.

  11. Monty Roberts' Public Demonstrations: Preliminary Report on the Heart Rate and Heart Rate Variability of Horses Undergoing Training during Live Audience Events.

    PubMed

    Loftus, Loni; Marks, Kelly; Jones-McVey, Rosie; Gonzales, Jose L; Fowler, Veronica L

    2016-09-09

    Effective training of horses relies on the trainer's awareness of learning theory and equine ethology, and should be undertaken with skill and time. Some trainers, such as Monty Roberts, share their methods through the medium of public demonstrations. This paper describes the opportunistic analysis of beat-to-beat (RR) intervals and heart rate variability (HRV) of ten horses being used in Monty Roberts' public demonstrations within the United Kingdom. RR and HRV was measured in the stable before training and during training. The HRV variables standard deviation of the RR interval (SDRR), root mean square of successive RR differences (RMSSD), geometric means standard deviation 1 (SD1) and 2 (SD2), along with the low and high frequency ratio (LF/HF ratio) were calculated. The minimum, average and maximum RR intervals were significantly lower in training (indicative of an increase in heart rate as measured in beats-per-minute) than in the stable ( p = 0.0006; p = 0.01; p = 0.03). SDRR, RMSSD, SD1, SD2 and the LF/HF ratio were all significantly lower in training than in the stable ( p = 0.001; p = 0.049; p = 0.049; p = 0.001; p = 0.01). When comparing the HR and HRV of horses during Join-up (®) to overall training, there were no significant differences in any variable with the exception of maximum RR which was significantly lower ( p = 0.007) during Join-up (®) , indicative of short increases in physical exertion (canter) associated with this training exercise. In conclusion, training of horses during public demonstrations is a low-moderate physiological, rather than psychological stressor for horses. The physiological stress responses observed within this study were comparable or less to those previously reported in the literature for horses being trained outside of public audience events. Furthermore, there is no evidence that the use of Join-up (®) alters HR and HRV in a way to suggest that this training method negatively affects the psychological welfare of

  12. Elevated Circulating Interleukin 33 Levels in Stable Renal Transplant Recipients at High Risk for Cardiovascular Events

    PubMed Central

    Mansell, Holly; Soliman, Mahmoud; Elmoselhi, Hamdi; Shoker, Ahmed

    2015-01-01

    Background The Major Adverse Cardiovascular Events calculator (CRCRTR-MACE) estimates the burden of cardiovascular risk in renal transplant recipients (RTR). Our recent study of 95 RTR reported the 7-year median risk of cardiovascular events (CVE) to be 9.97%, ranging from 1.93 to 84.27%. Nearly a third (28.4%) of the cohort was above 20% risk for a CVE. Since interleukins (ILs) as part of the inflammatory response may play a role in the pathogenesis of cardiovascular disease (CVD), we extended this study to identify which ILs are associated with high cardiovascular risk in this population. Methods Twenty-two ILs were measured by multiplexed fluorescent bead-based immunoassay in 95 RTR and 56 normal controls. Stepwise analysis after multivariate determination of significant demographic and inflammatory variables was performed between the high and low-CVD risk groups (which were arbitrarily set at scores <10% and ≥20%, respectively). Normalized data was presented as mean ± SD and non-normalized data as median (minimum–maximum). Significance was measured at <0.05. Results 27.5% of the low-risk and 31.3% of the high-risk groups had mean IL levels above the 95 percentile of the normal control levels. In the non-parametric analysis IL-6, 9, 16, 17 and 33 were significantly higher in the high-risk group compared to the control. Univariate analysis (UVA) of the high-risk group identified IL-33 as the only IL that remained significantly higher than the control and low-risk groups (p = 0.000). The percentage of patients with IL-33 levels above the 90 percentile of control value in the low and high-risk groups were 15.6% and 52.0%, respectively (p<0.002). UVA of factors significant to high IL-33 levels included estimated glomerular filtration rate (eGFR), while diabetes mellitus, serum phosphorus, microalbuminuria and age also remained significant in the multivariate analysis. Conclusion Circulating IL-33 level is positively associated with high CRCRTR-MACE score

  13. Performance of high flow rate samplers for respirable particle collection.

    PubMed

    Lee, Taekhee; Kim, Seung Won; Chisholm, William P; Slaven, James; Harper, Martin

    2010-08-01

    The American Conference of Governmental Industrial hygienists (ACGIH) lowered the threshold limit value (TLV) for respirable crystalline silica (RCS) exposure from 0.05 to 0.025 mg m(-3) in 2006. For a working environment with an airborne dust concentration near this lowered TLV, the sample collected with current standard respirable aerosol samplers might not provide enough RCS for quantitative analysis. Adopting high flow rate sampling devices for respirable dust containing silica may provide a sufficient amount of RCS to be above the limit of quantification even for samples collected for less than full shift. The performances of three high flow rate respirable samplers (CIP10-R, GK2.69, and FSP10) have been evaluated in this study. Eleven different sizes of monodisperse aerosols of ammonium fluorescein were generated with a vibrating orifice aerosol generator in a calm air chamber in order to determine the sampling efficiency of each sampler. Aluminum oxide particles generated by a fluidized bed aerosol generator were used to test (i) the uniformity of a modified calm air chamber, (ii) the effect of loading on the sampling efficiency, and (iii) the performance of dust collection compared to lower flow rate cyclones in common use in the USA (10-mm nylon and Higgins-Dewell cyclones). The coefficient of variation for eight simultaneous samples in the modified calm air chamber ranged from 1.9 to 6.1% for triplicate measures of three different aerosols. The 50% cutoff size ((50)d(ae)) of the high flow rate samplers operated at the flow rates recommended by manufacturers were determined as 4.7, 4.1, and 4.8 microm for CIP10-R, GK2.69, and FSP10, respectively. The mass concentration ratio of the high flow rate samplers to the low flow rate cyclones decreased with decreasing mass median aerodynamic diameter (MMAD) and high flow rate samplers collected more dust than low flow rate samplers by a range of 2-11 times based on gravimetric analysis. Dust loading inside the

  14. Event-Driven X-Ray CCD Detectors for High Energy Astrophysics

    NASA Technical Reports Server (NTRS)

    Ricker, George R.

    2004-01-01

    A viewgraph presentation describing the Event-Driven X- Ray CCD (EDCCD) detector system for high energy astrophysics is presented. The topics include: 1) EDCCD: Description and Advantages; 2) Summary of Grant Activity Carried Out; and 3) EDCCD Test System.

  15. Method for critical software event execution reliability in high integrity software

    SciTech Connect

    Kidd, M.E.

    1997-11-01

    This report contains viewgraphs on a method called SEER, which provides a high level of confidence that critical software driven event execution sequences faithfully exceute in the face of transient computer architecture failures in both normal and abnormal operating environments.

  16. High Heating Rates Affect Greatly the Inactivation Rate of Escherichia coli.

    PubMed

    Huertas, Juan-Pablo; Aznar, Arantxa; Esnoz, Arturo; Fernández, Pablo S; Iguaz, Asunción; Periago, Paula M; Palop, Alfredo

    2016-01-01

    Heat resistance of microorganisms can be affected by different influencing factors. Although, the effect of heating rates has been scarcely explored by the scientific community, recent researches have unraveled its important effect on the thermal resistance of different species of vegetative bacteria. Typically heating rates described in the literature ranged from 1 to 20°C/min but the impact of much higher heating rates is unclear. The aim of this research was to explore the effect of different heating rates, such as those currently achieved in the heat exchangers used in the food industry, on the heat resistance of Escherichia coli. A pilot plant tubular heat exchanger and a thermoresistometer Mastia were used for this purpose. Results showed that fast heating rates had a deep impact on the thermal resistance of E. coli. Heating rates between 20 and 50°C/min were achieved in the heat exchanger, which were much slower than those around 20°C/s achieved in the thermoresistometer. In all cases, these high heating rates led to higher inactivation than expected: in the heat exchanger, for all the experiments performed, when the observed inactivation had reached about seven log cycles, the predictions estimated about 1 log cycle of inactivation; in the thermoresistometer these differences between observed and predicted values were even more than 10 times higher, from 4.07 log cycles observed to 0.34 predicted at a flow rate of 70 mL/min and a maximum heating rate of 14.7°C/s. A quantification of the impact of the heating rates on the level of inactivation achieved was established. These results point out the important effect that the heating rate has on the thermal resistance of E. coli, with high heating rates resulting in an additional sensitization to heat and therefore an effective food safety strategy in terms of food processing.

  17. High Heating Rates Affect Greatly the Inactivation Rate of Escherichia coli

    PubMed Central

    Huertas, Juan-Pablo; Aznar, Arantxa; Esnoz, Arturo; Fernández, Pablo S.; Iguaz, Asunción; Periago, Paula M.; Palop, Alfredo

    2016-01-01

    Heat resistance of microorganisms can be affected by different influencing factors. Although, the effect of heating rates has been scarcely explored by the scientific community, recent researches have unraveled its important effect on the thermal resistance of different species of vegetative bacteria. Typically heating rates described in the literature ranged from 1 to 20°C/min but the impact of much higher heating rates is unclear. The aim of this research was to explore the effect of different heating rates, such as those currently achieved in the heat exchangers used in the food industry, on the heat resistance of Escherichia coli. A pilot plant tubular heat exchanger and a thermoresistometer Mastia were used for this purpose. Results showed that fast heating rates had a deep impact on the thermal resistance of E. coli. Heating rates between 20 and 50°C/min were achieved in the heat exchanger, which were much slower than those around 20°C/s achieved in the thermoresistometer. In all cases, these high heating rates led to higher inactivation than expected: in the heat exchanger, for all the experiments performed, when the observed inactivation had reached about seven log cycles, the predictions estimated about 1 log cycle of inactivation; in the thermoresistometer these differences between observed and predicted values were even more than 10 times higher, from 4.07 log cycles observed to 0.34 predicted at a flow rate of 70 mL/min and a maximum heating rate of 14.7°C/s. A quantification of the impact of the heating rates on the level of inactivation achieved was established. These results point out the important effect that the heating rate has on the thermal resistance of E. coli, with high heating rates resulting in an additional sensitization to heat and therefore an effective food safety strategy in terms of food processing. PMID:27563300

  18. Studying solutions at high shear rates: a dedicated microfluidics setup.

    PubMed

    Wieland, D C F; Garamus, V M; Zander, T; Krywka, C; Wang, M; Dedinaite, A; Claesson, P M; Willumeit-Römer, R

    2016-03-01

    The development of a dedicated small-angle X-ray scattering setup for the investigation of complex fluids at different controlled shear conditions is reported. The setup utilizes a microfluidics chip with a narrowing channel. As a consequence, a shear gradient is generated within the channel and the effect of shear rate on structure and interactions is mapped spatially. In a first experiment small-angle X-ray scattering is utilized to investigate highly concentrated protein solutions up to a shear rate of 300000 s(-1). These data demonstrate that equilibrium clusters of lysozyme are destabilized at high shear rates.

  19. A PLANETARY LENSING FEATURE IN CAUSTIC-CROSSING HIGH-MAGNIFICATION MICROLENSING EVENTS

    SciTech Connect

    Chung, Sun-Ju; Hwang, Kyu-Ha; Ryu, Yoon-Hyun; Lee, Chung-Uk E-mail: kyuha@kasi.re.kr E-mail: leecu@kasi.re.kr

    2012-05-20

    Current microlensing follow-up observations focus on high-magnification events because of the high efficiency of planet detection. However, central perturbations of high-magnification events caused by a planet can also be produced by a very close or a very wide binary companion, and the two kinds of central perturbations are not generally distinguished without time consuming detailed modeling (a planet-binary degeneracy). Hence, it is important to resolve the planet-binary degeneracy that occurs in high-magnification events. In this paper, we investigate caustic-crossing high-magnification events caused by a planet and a wide binary companion. From this investigation, we find that because of the different magnification excess patterns inside the central caustics induced by the planet and the binary companion, the light curves of the caustic-crossing planetary-lensing events exhibit a feature that is discriminated from those of the caustic-crossing binary-lensing events, and the feature can be used to immediately distinguish between the planetary and binary companions. The planetary-lensing feature appears in the interpeak region between the two peaks of the caustic-crossings. The structure of the interpeak region for the planetary-lensing events is smooth and convex or boxy, whereas the structure for the binary-lensing events is smooth and concave. We also investigate the effect of a finite background source star on the planetary-lensing feature in the caustic-crossing high-magnification events. From this, we find that the convex-shaped interpeak structure appears in a certain range that changes with the mass ratio of the planet to the planet-hosting star.

  20. Low stroke rate and few thrombo-embolic events after HeartMate II implantation under mild anticoagulation.

    PubMed

    Menon, Ares K; Götzenich, Andreas; Sassmannshausen, Helena; Haushofer, Marcus; Autschbach, Rüdiger; Spillner, Jan W

    2012-08-01

    Bleeding and thrombo-embolism are two of the most threatening adverse events associated with the use of continuous flow left ventricular assist devices (LVADs) in the treatment of severe heart failure. We analysed our LVAD patients treated with the HeartMate II (HM II) device by following a low anticoagulation regimen. Between 2008 and February 2011, we implanted 40 HM II LVADs in our institution. Intention to treat was bridge to transplant in 25, destination therapy in 9, bridge to candidacy in 5 cases and bridge to recovery in 1 case. Heparin was started only after 24 h postoperatively, and Phenprocumon (Phen) was started after removal of all chest drains. International normalized ratio (INR) target in the years 2008-2009 was 2.5, and 2.0-2.5 since 2010. Acetyl salicylic acid (ASA) was prescribed 50-100 mg/day only in patients <55 years or in case of severe atherosclerotic disease of the right coronary artery. All data were analysed consecutively concerning thrombo-embolic and bleeding events. Fifty-two percent of the patients were in INTERMACS level 1 or 2 at the time of implantation. The mean age was 58 ± 11 years, and the mean days under LVAD was 241 days (maximum: 1052 days). The survival rate was 87.5% after 30 years and 75% in the long term. Early postoperatively, no strokes or thrombo-embolic events occurred. In the long term, two patients suffered from ischaemic strokes, but recovered well. In both of these index events, the INR was lasting below 1.4. One of these two patients developed pump thrombosis additionally. Only three patients (ASA + Phen) developed gastrointestinal bleeding (7.5%). Two patients were withdrawn from Phen + ASA because of multiple angiodysplasia. Compared with the literature, even a mild anticoagulation protocol does not increase the risk of thrombotic events, but reduces bleeding events in the use of an HM II LVAD.

  1. Measuring growth rate in high-throughput growth phenotyping.

    PubMed

    Blomberg, Anders

    2011-02-01

    Growth rate is an important variable and parameter in biology with a central role in evolutionary, functional genomics, and systems biology studies. In this review the pros and cons of the different technologies presently available for high-throughput measurements of growth rate are discussed. Growth rate can be measured in liquid microcultivation of individual strains, in competition between strains, as growing colonies on agar, as division of individual cells, and estimated from molecular reporters. Irrespective of methodology, statistical issues such as spatial biases and batch effects are crucial to investigate and correct for to ensure low false discovery rates. The rather low correlations between studies indicate that cross-laboratory comparison and standardization are pressing issue to assure high-quality and comparable growth-rate data. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Slow rate of molecular evolution in high-elevation hummingbirds.

    PubMed

    Bleiweiss, R

    1998-01-20

    Estimates of relative rates of molecular evolution from a DNA-hybridization phylogeny for 26 hummingbird species provide evidence for a negative association between elevation and rate of single-copy genome evolution. This effect of elevation on rate remains significant even after taking into account a significant negative association between body mass and molecular rate. Population-level processes do not appear to account for these patterns because (i) all hummingbirds breed within their first year and (ii) the more extensive subdivision and speciation of bird populations living at high elevations predicts a positive association between elevation and rate. The negative association between body mass and molecular rate in other organisms has been attributed to higher mutation rates in forms with higher oxidative metabolism. As ambient oxygen tensions and temperature decrease with elevation, the slow rate of molecular evolution in high-elevation hummingbirds also may have a metabolic basis. A slower rate of single-copy DNA change at higher elevations suggests that the dynamics of molecular evolution cannot be separated from the environmental context.

  3. Air Shower Events of High-Energy Cosmic Rays Measured at Seoul, South Korea

    NASA Astrophysics Data System (ADS)

    Cho, Wooram; Shin, Jae-Ik; Kim, Hongki; Lee, Seulgi; Lim, Sunin; Nam, Sinwoo; Yang, Jongmann; Cheon, Byunggu; Bang, Hyungchan; Kwon, Youngjoon

    2011-09-01

    The COsmic ray Research and Education Array (COREA) collaboration has installed an array of six detector stations at two high schools in and near Seoul, Korea for measurement of air-shower events from high-energy cosmic rays. Three stations are installed at each site, where each station consists of four plastic scintillation detectors covering an area of 2m2. In this presentation, we report the currenst status of the COREA project, describing the experimental equipment and measurement of coincident events.

  4. Fermi gamma-ray burst monitor detector performance at very high counting rates

    NASA Astrophysics Data System (ADS)

    Bhat, P. N.; Fishman, G. J.; Briggs, M. S.; Connaughton, V.; Meegan, C. A.; Paciesas, W. S.; Wilson-Hodge, C.; Xiong, S.

    2014-11-01

    The Gamma-ray Burst Monitor consists of 12 sodium iodide and 2 bismuth germanate scintillation detectors designed to enhance the scientific returns from Fermi in the study of γ-ray bursts. It has a fixed non-paralyzing dead time of 2.604 μs for each detected event except for those in the overflow channel of the 12 bit analog to digital converter of each detector, which have a longer dead time of 10.42 μs. At very high counting rates the pulse pile-up effect in the detectors leads to spectral distortions and also to additional event losses. These effects are relevant for the spectral analysis of high-flux astrophysical events such as gamma-ray bursts, soft gamma repeaters and solar flares, as well as terrestrial gamma-ray flashes. In this paper we present the results of post-launch tests using engineering detectors and equipment on the ground, along with detailed simulations of these effects at very high counting rates. The simulations enable us to assess the qualitative and quantitative changes in spectral shapes and event losses at different count rates. The observed spectra at various count rates using high intensity radioactive sources such as Cs137 and Co60 agree well with the simulated spectra. We also re-test the analytical model developed previously to correct for the pulse pile-up effects in GBM detectors. We also study the expected spectral distortions of specific spectral models commonly used in GRB analysis, including the Band model and power-law models with and without a high-energy cutoff.

  5. Constructing An Event Based Aerosol Product Under High Aerosol Loading Conditions

    NASA Astrophysics Data System (ADS)

    Levy, R. C.; Shi, Y.; Mattoo, S.; Remer, L. A.; Zhang, J.

    2016-12-01

    High aerosol loading events, such as the Indonesia's forest fire in Fall 2015 or the persistent wintertime haze near Beijing, gain tremendous interests due to their large impact on regional visibility and air quality. Understanding the optical properties of these events and further being able to simulate and predict these events are beneficial. However, it is a great challenge to consistently identify and then retrieve aerosol optical depth (AOD) from passive sensors during heavy aerosol events. Some reasons include:1). large differences between optical properties of high-loading aerosols and those under normal conditions, 2) spectral signals of optically thick aerosols can be mistaken with surface depending on aerosol types, and 3) Extremely optically thick aerosol plumes can also be misidentified as clouds due to its high optical thickness. Thus, even under clear-sky conditions, the global distribution of extreme aerosol events is not well captured in datasets such as the MODIS Dark-Target (DT) aerosol product. In this study, with the synthetic use of OMI Aerosol Index, MODIS cloud product, and operational DT product, the heavy smoke events over the seven sea region are identified and retrieved over the dry season. An event based aerosol product that would compensate the standard "global" aerosol retrieval will be created and evaluated. The impact of missing high AOD retrievals on the regional aerosol climatology will be studied using this newly developed research product.

  6. Advances in solid polymer electrochemical capacitors for high rate applications

    NASA Astrophysics Data System (ADS)

    Lian, Keryn; Gao, Han

    2011-06-01

    All solid electrochemical capacitors (EC) have been demonstrated using proton conducting silicotungstic acid (SiWA) and poly(vinyl alcohol) (PVA) based polymer electrolytes. Graphite electrodes were utilized for electrochemical double layer capacitors (EDLC), while RuO2 electrodes were employed as pseudocapacitive electrodes. Both solid EDLC and pseudocapacitors exhibited very high charge/discharge rate capability. Especially for solid EDLC, a charge/discharge rate of 25 V/s and a 10 ms time constant ("factor of merit") were obtained. The rate capability of the solid EC is attributable to thin film thickness, good proton conductivity of the polymer electrolyte, and intimate contact between electrode and electrolyte. These results demonstrate promise of polymer electrolytes as enablers of high rate and high performance solid EC devices.

  7. Stretching Behavior of Red Blood Cells at High Strain Rates

    NASA Astrophysics Data System (ADS)

    Mancuso, Jordan; Ristenpart, William

    2016-11-01

    Most work on the mechanical behavior of red blood cells (RBCs) has focused on simple shear flows. Relatively little work has examined RBC deformations in the physiologically important extensional flow that occurs at the entrance to a constriction. In particular, previous work suggests that RBCs rapidly stretch out and then retract upon entering the constriction, but to date no model predicts this behavior for the extremely high strain rates typically experienced there. In this work, we use high speed video to perform systematic measurements of the dynamic stretching behavior of RBCs as they enter a microfluidic constriction. We demonstrate that a simple viscoelastic model captures the observed stretching dynamics, up to strain rates as high as 1000 s-1. The results indicate that the effective elastic modulus of the RBC membrane at these strain rates is an order of magnitude larger than moduli measured by micropipette aspiration or other low strain rate techniques.

  8. High rate material behaviour at hot forming conditions

    NASA Astrophysics Data System (ADS)

    Meyer, Lothar W.; Kuprin, Corinna; Halle, Thorsten

    2009-03-01

    Modern processes of hot forming use very high strain rates and large, mostly incrementally applied strains. For the simulation of such forming processes relevant material data are needed, which have to be recorded under accordant forming conditions. This places extraordinary demands on the experimental technique, because high temperatures, high strain rates and large strains have to be implemented simultaneously. In the following contribution such an aligned experimental technique is introduced. In order to apply a very large range of strain rate, compression tests are performed using different technical equipment up to a drop tower and Hopkinson pressure bar. To reach large plastic strains, a hot torsion test was developed, which allowed true plastic shear strains up to 10 at strain rates in the order of 100 1/s at hot forming temperatures.

  9. Why Are Most Ground Level Events Associated with High Fe/O Ratios?

    NASA Technical Reports Server (NTRS)

    von Rosenvinge, Tycho T.; Richardson, Ian G.; Cane, Hilary V.

    2010-01-01

    In a seminal paper about Ground Level Events (GLEs), Dietrich and Lopate (1999) reported on 24 GLEs from April, 1973 to May, 1998. They noted that alt but one of these GLEs, June 15, 1991, were associated with a Solar Energetic Particle (SEP) event with an enhanced Fe/O ratio. The Fe/O ratio observed for the June 15, 1991 event was only 0.03, well below the nominal coronal abundance of Fe/O = 0.134. For the remaining events, Fe/O ranged from 0.27 to over 3, welt over the nominal coronal value. During Solar Cycle 23, 14 more GLEs were observed, only one of which had very low Fe/O. This was the event of January 20, 2005, the largest ground-level neutron monitor event in 49 years. We will report on our efforts to find out whether the events of June 15, 1991 and January 20, 2005 have features in common, besides high Fe/O, that distinguish them from all other GLE events and may help determine the cause of elevated Fe/O in almost all GLE events. We will use energetic particle, magnetic field, and solar wind plasma data from NASA's IMP-8 Wind, and ACE spacecraft.

  10. Solidification at the High and Low Rate Extreme

    SciTech Connect

    Meco, Halim

    2004-12-19

    The microstructures formed upon solidification are strongly influenced by the imposed growth rates on an alloy system. Depending on the characteristics of the solidification process, a wide range of growth rates is accessible. The prevailing solidification mechanisms, and thus the final microstructure of the alloy, are governed by these imposed growth rates. At the high rate extreme, for instance, one can have access to novel microstructures that are unattainable at low growth rates. While the low growth rates can be utilized for the study of the intrinsic growth behavior of a certain phase growing from the melt. Although the length scales associated with certain processes, such as capillarity, and the diffusion of heat and solute, are different at low and high rate extremes, the phenomena that govern the selection of a certain microstructural length scale or a growth mode are the same. Consequently, one can analyze the solidification phenomena at both high and low rates by using the same governing principles. In this study, we examined the microstructural control at both low and high extremes. For the high rate extreme, the formation of crystalline products and factors that control the microstructure during rapid solidification by free-jet melt spinning are examined in Fe-Si-B system. Particular attention was given to the behavior of the melt pool at different quench-wheel speeds. Since the solidification process takes place within the melt-pool that forms on the rotating quench-wheel, we examined the influence of melt-pool dynamics on nucleation and growth of crystalline solidification products and glass formation. High-speed imaging of the melt-pool, analysis of ribbon microstructure, and measurement of ribbon geometry and surface character all indicate upper and lower limits for melt-spinning rates for which nucleation can be avoided, and fully amorphous ribbons can be achieved. Comparison of the relevant time scales reveals that surface-controlled melt

  11. A Drug Safety Rating System Based on Postmarketing Costs Associated with Adverse Events and Patient Outcomes.

    PubMed

    Hoffman, Keith B; Dimbil, Mo; Kyle, Robert F; Tatonetti, Nicholas P; Erdman, Colin B; Demakas, Andrea; Chen, Dingguo; Overstreet, Brian M

    2015-12-01

    Given the multiple limitations associated with relatively homogeneous preapproval clinical trials, inadequate data disclosures, slow reaction times from regulatory bodies, and deep-rooted bias against disclosing and publishing negative results, there is an acute need for the development of analytics that reflect drug safety in heterogeneous, real-world populations. To develop a drug safety statistic that estimates downstream medical costs associated with serious adverse events (AEs) and unfavorable patient outcomes associated with the use of 706 FDA-approved drugs. All primary suspect case reports for each drug were collected from the FDA's Adverse Event Reporting System database (FAERS) from 2010-2014. The Medical Dictionary for Regulatory Activities (MedDRA) was used to code serious AEs and outcomes, which were tallied for each case report. Medical costs associated with AEs and poor patient outcomes were derived from Agency for Healthcare Research and Quality (AHRQ) survey data, and their corresponding ICD-9-CM codes were mapped to MedDRA terms. Nonserious AEs and outcomes were not included. For each case report, either the highest AE cost or, if no eligible AE was listed, the highest outcome cost was used. All costed cases were aggregated for each drug and divided by the number of patients exposed to obtain a downstream estimated direct medical cost burden per exposure. Each drug was assigned a corresponding 1-100 point total. The 706 drugs showed an exponential distribution of downstream costs, and the data were transformed using the natural log to approximate a normal distribution. The minimum score was 8.29, and the maximum score was 99.25, with a mean of 44.32. Drugs with the highest individual scores tended to be kinase inhibitors, thalidomide analogs, and endothelin receptor antagonists. When scores were analyzed across Established Pharmacologic Class (EPC), the kinase inhibitor and endothelin receptor antagonist classes had the highest total. However

  12. Evidence That the Pi Release Event Is the Rate-Limiting Step in the Nitrogenase Catalytic Cycle.

    PubMed

    Yang, Zhi-Yong; Ledbetter, Rhesa; Shaw, Sudipta; Pence, Natasha; Tokmina-Lukaszewska, Monika; Eilers, Brian; Guo, Qingjuan; Pokhrel, Nilisha; Cash, Valerie L; Dean, Dennis R; Antony, Edwin; Bothner, Brian; Peters, John W; Seefeldt, Lance C

    2016-07-05

    Nitrogenase reduction of dinitrogen (N2) to ammonia (NH3) involves a sequence of events that occur upon the transient association of the reduced Fe protein containing two ATP molecules with the MoFe protein that includes electron transfer, ATP hydrolysis, Pi release, and dissociation of the oxidized, ADP-containing Fe protein from the reduced MoFe protein. Numerous kinetic studies using the nonphysiological electron donor dithionite have suggested that the rate-limiting step in this reaction cycle is the dissociation of the Fe protein from the MoFe protein. Here, we have established the rate constants for each of the key steps in the catalytic cycle using the physiological reductant flavodoxin protein in its hydroquinone state. The findings indicate that with this reductant, the rate-limiting step in the reaction cycle is not protein-protein dissociation or reduction of the oxidized Fe protein, but rather events associated with the Pi release step. Further, it is demonstrated that (i) Fe protein transfers only one electron to MoFe protein in each Fe protein cycle coupled with hydrolysis of two ATP molecules, (ii) the oxidized Fe protein is not reduced when bound to MoFe protein, and (iii) the Fe protein interacts with flavodoxin using the same binding interface that is used with the MoFe protein. These findings allow a revision of the rate-limiting step in the nitrogenase Fe protein cycle.

  13. The tell-tale heart: heart rate fluctuations index objective and subjective events during a game of chess

    PubMed Central

    Leone, María J.; Petroni, Agustín; Fernandez Slezak, Diego; Sigman, Mariano

    2012-01-01

    During a decision-making process, the body changes. These somatic changes have been related to specific cognitive events and also have been postulated to assist decision-making indexing possible outcomes of different options. We used chess to analyze heart rate (HR) modulations on specific cognitive events. In a chess game, players have a limited time-budget to make about 40 moves (decisions) that can be objectively evaluated and retrospectively assigned to specific subjectively perceived events, such as setting a goal and the process to reach a known goal. We show that HR signals events: it predicts the conception of a plan, the concrete analysis of variations or the likelihood to blunder by fluctuations before to the move, and it reflects reactions, such as a blunder made by the opponent, by fluctuations subsequent to the move. Our data demonstrate that even if HR constitutes a relatively broad marker integrating a myriad of physiological variables, its dynamic is rich enough to reveal relevant episodes of inner thought. PMID:23060777

  14. Fault Tolerance Implementation within SRAM Based FPGA Designs based upon Single Event Upset Occurrence Rates

    NASA Technical Reports Server (NTRS)

    Berg, Melanie

    2006-01-01

    Emerging technology is enabling the design community to consistently expand the amount of functionality that can be implemented within Integrated Circuits (ICs). As the number of gates placed within an FPGA increases, the complexity of the design can grow exponentially. Consequently, the ability to create reliable circuits has become an incredibly difficult task. In order to ease the complexity of design completion, the commercial design community has developed a very rigid (but effective) design methodology based on synchronous circuit techniques. In order to create faster, smaller and lower power circuits, transistor geometries and core voltages have decreased. In environments that contain ionizing energy, such a combination will increase the probability of Single Event Upsets (SEUs) and will consequently affect the state space of a circuit. In order to combat the effects of radiation, the aerospace community has developed several "Hardened by Design" (fault tolerant) design schemes. This paper will address design mitigation schemes targeted for SRAM Based FPGA CMOS devices. Because some mitigation schemes may be over zealous (too much power, area, complexity, etc.. . .), the designer should be conscious that system requirements can ease the amount of mitigation necessary for acceptable operation. Therefore, various degrees of Fault Tolerance will be demonstrated along with an analysis of its effectiveness.

  15. Authoritative School Climate and High School Dropout Rates

    ERIC Educational Resources Information Center

    Jia, Yuane; Konold, Timothy R.; Cornell, Dewey

    2016-01-01

    This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high…

  16. Authoritative School Climate and High School Dropout Rates

    ERIC Educational Resources Information Center

    Jia, Yuane; Konold, Timothy R.; Cornell, Dewey

    2016-01-01

    This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high…

  17. High-rate squeezing process of bulk metallic glasses

    PubMed Central

    Fan, Jitang

    2017-01-01

    High-rate squeezing process of bulk metallic glasses from a cylinder into an intact sheet achieved by impact loading is investigated. Such a large deformation is caused by plastic flow, accompanied with geometrical confinement, shear banding/slipping, thermo softening, melting and joining. Temperature rise during the high-rate squeezing process makes a main effect. The inherent mechanisms are illustrated. Like high-pressure torsion (HPT), equal channel angular pressing (ECAP) and surface mechanical attrition treatments (SMAT) for refining grain of metals, High-Rate Squeezing (HRS), as a multiple-functions technique, not only creates a new road of processing metallic glasses and other metallic alloys for developing advanced materials, but also directs a novel technology of processing, grain refining, coating, welding and so on for treating materials. PMID:28338092

  18. High-rate squeezing process of bulk metallic glasses

    NASA Astrophysics Data System (ADS)

    Fan, Jitang

    2017-03-01

    High-rate squeezing process of bulk metallic glasses from a cylinder into an intact sheet achieved by impact loading is investigated. Such a large deformation is caused by plastic flow, accompanied with geometrical confinement, shear banding/slipping, thermo softening, melting and joining. Temperature rise during the high-rate squeezing process makes a main effect. The inherent mechanisms are illustrated. Like high-pressure torsion (HPT), equal channel angular pressing (ECAP) and surface mechanical attrition treatments (SMAT) for refining grain of metals, High-Rate Squeezing (HRS), as a multiple-functions technique, not only creates a new road of processing metallic glasses and other metallic alloys for developing advanced materials, but also directs a novel technology of processing, grain refining, coating, welding and so on for treating materials.

  19. Breakdown Limit Studies in High-Rate Gaseous Detectors

    NASA Technical Reports Server (NTRS)

    Ivaniouchenkov, Yu; Fonte, P.; Peskov, V.; Ramsey, B. D.

    1999-01-01

    We report results from a systematic study of breakdown limits for novel high-rate gaseous detectors: MICROMEGAS, CAT and GEM, together with more conventional devices such as thin-gap parallel-mesh chambers and high-rate wire chambers. It was found that for all these detectors, the maximum achievable pin, before breakdown appears, drops dramatically with incident flux, and is sometimes inversely proportional to it. Further, in the presence of alpha particles, typical of the breakgrounds in high-energy experiments, additional gain drops of 1-2 orders of magnitude were observed for many detectors. It was found that breakdowns at high rates occur through what we have termed an "accumulative" mechanism, which does not seem to have been previously reported in the literature. Results of these studies may help in choosing the optimum detector for given experimental conditions.

  20. A test for Improvement of high resolution Quantitative Precipitation Estimation for localized heavy precipitation events

    NASA Astrophysics Data System (ADS)

    Lee, Jung-Hoon; Roh, Joon-Woo; Park, Jeong-Gyun

    2017-04-01

    Accurate estimation of precipitation is one of the most difficult and significant tasks in the area of weather diagnostic and forecasting. In the Korean Peninsula, heavy precipitations are caused by various physical mechanisms, which are affected by shortwave trough, quasi-stationary moisture convergence zone among varying air masses, and a direct/indirect effect of tropical cyclone. In addition to, various geographical and topographical elements make production of temporal and spatial distribution of precipitation is very complicated. Especially, localized heavy rainfall events in South Korea generally arise from mesoscale convective systems embedded in these synoptic scale disturbances. In weather radar data with high temporal and spatial resolution, accurate estimation of rain rate from radar reflectivity data is too difficult. Z-R relationship (Marshal and Palmer 1948) have adapted representatively. In addition to, several methods such as support vector machine (SVM), neural network, Fuzzy logic, Kriging were utilized in order to improve the accuracy of rain rate. These methods show the different quantitative precipitation estimation (QPE) and the performances of accuracy are different for heavy precipitation cases. In this study, in order to improve the accuracy of QPE for localized heavy precipitation, ensemble method for Z-R relationship and various techniques was tested. This QPE ensemble method was developed by a concept based on utilizing each advantage of precipitation calibration methods. The ensemble members were produced for a combination of different Z-R coefficient and calibration method.

  1. High power, high efficiency millimeter wavelength traveling wave tubes for high rate communications from deep space

    NASA Technical Reports Server (NTRS)

    Dayton, James A., Jr.

    1991-01-01

    The high-power transmitters needed for high data rate communications from deep space will require a new class of compact, high efficiency traveling wave tubes (TWT's). Many of the recent TWT developments in the microwave frequency range are generically applicable to mm wave devices, in particular much of the technology of computer aided design, cathodes, and multistage depressed collectors. However, because TWT dimensions scale approximately with wavelength, mm wave devices will be physically much smaller with inherently more stringent fabrication tolerances and sensitivity to thermal dissipation.

  2. High power, high efficiency millimeter wavelength traveling wave tubes for high rate communications from deep space

    NASA Technical Reports Server (NTRS)

    Dayton, James A., Jr.

    1991-01-01

    The high-power transmitters needed for high data rate communications from deep space will require a new class of compact, high efficiency traveling wave tubes (TWT's). Many of the recent TWT developments in the microwave frequency range are generically applicable to mm wave devices, in particular much of the technology of computer aided design, cathodes, and multistage depressed collectors. However, because TWT dimensions scale approximately with wavelength, mm wave devices will be physically much smaller with inherently more stringent fabrication tolerances and sensitivity to thermal dissipation.

  3. Reduced fatalism and increased prevention behavior after two high-profile lung cancer events.

    PubMed

    Portnoy, David B; Leach, Corinne R; Kaufman, Annette R; Moser, Richard P; Alfano, Catherine M

    2014-01-01

    The positive impact of media coverage of high-profile cancer events on cancer prevention behaviors is well-established. However, less work has focused on potential adverse psychological reactions to such events, such as fatalism. Conducting 3 studies, the authors explored how the lung cancer death of Peter Jennings and diagnosis of Dana Reeve in 2005 related to fatalism. Analysis of a national media sample in Study 1 found that media coverage of these events often focused on reiterating the typical profile of those diagnosed with lung cancer; 38% of the media mentioned at least 1 known risk factor for lung cancer, most often smoking. Data from a nationally representative survey in Study 2 found that respondents reported lower lung cancer fatalism, after, compared with before, the events (OR = 0.16, 95% CI [0.03, 0.93]). A sustained increase in call volume to the national tobacco Quitline after these events was found in Study 3. These results suggest that there is a temporal association between high-profile cancer events, the subsequent media coverage, psychological outcomes, and cancer prevention behaviors. These results suggest that high-profile cancer events could be leveraged as an opportunity for large-scale public heath communication campaigns through the dissemination of cancer prevention messages and services.

  4. Evolution of high tooth replacement rates in sauropod dinosaurs.

    PubMed

    D'Emic, Michael D; Whitlock, John A; Smith, Kathlyn M; Fisher, Daniel C; Wilson, Jeffrey A

    2013-01-01

    Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days). Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size), and derived titanosaurs and diplodocoids independently evolved the highest known tooth replacement rates among archosaurs.

  5. Evolution of High Tooth Replacement Rates in Sauropod Dinosaurs

    PubMed Central

    Smith, Kathlyn M.; Fisher, Daniel C.; Wilson, Jeffrey A.

    2013-01-01

    Background Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. Methodology/Principal Findings We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days). Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. Conclusions/Significance Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size), and derived titanosaurs and diplodocoids independently

  6. High rates of death and hospitalization follow bone fracture among hemodialysis patients.

    PubMed

    Tentori, Francesca; McCullough, Keith; Kilpatrick, Ryan D; Bradbury, Brian D; Robinson, Bruce M; Kerr, Peter G; Pisoni, Ronald L

    2014-01-01

    Altered bone structure and function contribute to the high rates of fractures in dialysis patients compared to the general population. Fracture events may increase the risk of subsequent adverse clinical outcomes. Here we assessed the incidence of post-fracture morbidity and mortality in an international cohort of 34,579 in-center hemodialysis patients in the Dialysis Outcomes and Practice Patterns Study (DOPPS). We estimated country-specific rates of fractures requiring a hospital admission and associated length of stay in the hospital. Incidence rates of death and of a composite event of death/rehospitalization were estimated for 1 year after fracture. Overall, 3% of participants experienced a fracture. Fracture incidence varied across countries, from 12 events/1000 patient-years (PY) in Japan to 45/1000 PY in Belgium. In all countries, fracture rates were higher in the hemodialysis group compared to those reported for the general population. Median length of stay ranged from 7 to 37 days in the United States and Japan, respectively. In most countries, postfracture mortality rates exceeded 500/1000 PY and death/rehospitalization rates exceeded 1500/1000 PY. Fracture patients had higher unadjusted rates of death (3.7-fold) and death/rehospitalization (4.0-fold) compared to the overall DOPPS population. Mortality and hospitalization rates were highest in the first month after the fracture and declined thereafter. Thus, the high frequency of fractures and increased adverse outcomes following a fracture pose a significant health burden for dialysis patients. Fracture prevention strategies should be identified and applied broadly in nephrology practices.

  7. Varying Definitions for Periprocedural Myocardial Infarction Alter Event Rates and Prognostic Implications

    PubMed Central

    Idris, Hanan; Lo, Sidney; Shugman, Ibrahim M.; Saad, Yousef; Hopkins, Andrew P.; Mussap, Christian; Leung, Dominic; Thomas, Liza; Juergens, Craig P.; French, John K.

    2014-01-01

    Background Periprocedural myocardial infarction (PMI) has had several definitions in the last decade, including the Society for Cardiovascular Angiography and Interventions (SCAI) definition, that requires marked biomarker elevations congruent with surgical PMI criteria. Methods and Results The aim of this study was to examine the definition‐based frequencies of PMI and whether they influenced the reported association between PMI and increased rates of late death/ myocardial infarction (MI). We studied 742 patients; 492 (66%) had normal troponin T (TnT) levels and 250 (34%) had elevated, but stable or falling, TnT levels. PMI, using the 2007 and the 2012 universal definition, occurred in 172 (23.2%) and in 99 (13.3%) patients, respectively, whereas 19 (2.6%) met the SCAI PMI definition (P<0.0001). Among patients with PMI using the 2012 definition, occlusion of a side branch ≤1 mm occurred in 48 patients (48.5%) and was the most common angiographic finding for PMI. The rates of death/MI at 2 years in patients with, compared to those without, PMI was 14.7% versus 10.1% (P=0.087) based on the 2007 definition, 16.9% versus 10.3% (P=0.059) based on the 2012 definition, and 29.4% versus 10.7% (P=0.015) based on the SCAI definition. Conclusion In this study, PMI, according to the SCAI definition, was associated with more‐frequent late death/MI, with ≈20% of all patients, who had PMI using the 2007 universal MI definition, not having SCAI‐defined PMI. Categorizing these latter patients as SCAI‐defined no PMI did not alter the rate of death/MI among no‐PMI patients. PMID:25359403

  8. Varying definitions for periprocedural myocardial infarction alter event rates and prognostic implications.

    PubMed

    Idris, Hanan; Lo, Sidney; Shugman, Ibrahim M; Saad, Yousef; Hopkins, Andrew P; Mussap, Christian; Leung, Dominic; Thomas, Liza; Juergens, Craig P; French, John K

    2014-10-30

    Periprocedural myocardial infarction (PMI) has had several definitions in the last decade, including the Society for Cardiovascular Angiography and Interventions (SCAI) definition, that requires marked biomarker elevations congruent with surgical PMI criteria. The aim of this study was to examine the definition-based frequencies of PMI and whether they influenced the reported association between PMI and increased rates of late death/ myocardial infarction (MI). We studied 742 patients; 492 (66%) had normal troponin T (TnT) levels and 250 (34%) had elevated, but stable or falling, TnT levels. PMI, using the 2007 and the 2012 universal definition, occurred in 172 (23.2%) and in 99 (13.3%) patients, respectively, whereas 19 (2.6%) met the SCAI PMI definition (P<0.0001). Among patients with PMI using the 2012 definition, occlusion of a side branch ≤1 mm occurred in 48 patients (48.5%) and was the most common angiographic finding for PMI. The rates of death/MI at 2 years in patients with, compared to those without, PMI was 14.7% versus 10.1% (P=0.087) based on the 2007 definition, 16.9% versus 10.3% (P=0.059) based on the 2012 definition, and 29.4% versus 10.7% (P=0.015) based on the SCAI definition. In this study, PMI, according to the SCAI definition, was associated with more-frequent late death/MI, with ≈20% of all patients, who had PMI using the 2007 universal MI definition, not having SCAI-defined PMI. Categorizing these latter patients as SCAI-defined no PMI did not alter the rate of death/MI among no-PMI patients. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  9. The influence of the thermal environment and other early life events on growth rate of piglets during lactation.

    PubMed

    Pedersen, L J; Schild, S-L Aa; Malmkvist, J

    2015-09-01

    The effects of early life events on average daily weight gain from birth to day 21 (ADG) of suckling pigs kept at different room temperatures (15°C, 20°C and 25°C) from birth to weaning were investigated. Data were collected from litters born by 61 sows in a loose housing system. The ADG for piglets with low birth weight (estimated for birth weights below the 10% percentile) was estimated to be 20 to 30 g higher per day at room temperature 20°C to 25°C compared with 15°C. In contrast, the ADG during the lactation period decreased for larger piglets (estimated for birth weights above the 10% percentile) by 28 g/day at room temperature 25°C compared with 15°C. Thus, high ambient temperatures (20°C to 25°C) are favourable for the growth in smaller piglets during lactation. Neither latency to first suckle nor birth-induced hypoxia, measured as concentration of umbilical cord lactate, affected the growth rate of the piglets. Lowest rectal temperature during the first 24 h after birth had a long-term negative effect on ADG (P<0.05), so that piglets with a lowest rectal temperature of 32.8°C (10% percentile) had an ADG which was on average 19 g lower per day than piglets with a rectal temperature of 37.3°C (90% percentile). Our results showed that hypothermia at birth, low birth weight and high number of suckling piglets lead to reduced ADG during the suckling period. The results suggest that keeping the room temperature at 20°C during lactation to some extent could compensate for the otherwise negative effects of low birth weight on ADG in piglets without decreasing the ADG of high birth weight piglets. However, to avoid hypothermia in the smallest piglets it may be beneficial to increase the room temperature above 20°C during the farrowing period of loose housed sows.

  10. High rate and stable cycling of lithium metal anode

    SciTech Connect

    Qian, Jiangfeng; Henderson, Wesley A.; Xu, Wu; Bhattacharya, Priyanka; Engelhard, Mark H.; Borodin, Oleg; Zhang, Jiguang

    2015-02-20

    Lithium (Li) metal is an ideal anode material for rechargeable batteries. However, dendritic Li growth and limited Coulombic efficiency (CE) during repeated Li deposition/stripping processes have prevented the application of this anode in rechargeable Li metal batteries, especially for use at high current densities. Here, we report that the use of highly concentrated electrolytes composed of ether solvents and the lithium bis(fluorosulfonyl)imide (LiFSI) salt enables the high rate cycling of a Li metal anode at high CE (up to 99.1 %) without dendrite growth. With 4 M LiFSI in 1,2-dimethoxyethane (DME) as the electrolyte, a Li|Li cell can be cycled at high rates (10 mA cm-2) for more than 6000 cycles with no increase in the cell impedance, and a Cu|Li cell can be cycled at 4 mA cm-2 for more than 1000 cycles with an average CE of 98.4%. These excellent high rate performances can be attributed to the increased solvent coordination and increased availability of Li+ concentration in the electrolyte. Lastly, further development of this electrolyte may lead to practical applications for Li metal anode in rechargeable batteries. The fundamental mechanisms behind the high rate ion exchange and stability of the electrolytes also shine light on the stability of other electrochemical systems.

  11. High rate and stable cycling of lithium metal anode

    DOE PAGES

    Qian, Jiangfeng; Henderson, Wesley A.; Xu, Wu; ...

    2015-02-20

    Lithium (Li) metal is an ideal anode material for rechargeable batteries. However, dendritic Li growth and limited Coulombic efficiency (CE) during repeated Li deposition/stripping processes have prevented the application of this anode in rechargeable Li metal batteries, especially for use at high current densities. Here, we report that the use of highly concentrated electrolytes composed of ether solvents and the lithium bis(fluorosulfonyl)imide (LiFSI) salt enables the high rate cycling of a Li metal anode at high CE (up to 99.1 %) without dendrite growth. With 4 M LiFSI in 1,2-dimethoxyethane (DME) as the electrolyte, a Li|Li cell can be cycledmore » at high rates (10 mA cm-2) for more than 6000 cycles with no increase in the cell impedance, and a Cu|Li cell can be cycled at 4 mA cm-2 for more than 1000 cycles with an average CE of 98.4%. These excellent high rate performances can be attributed to the increased solvent coordination and increased availability of Li+ concentration in the electrolyte. Lastly, further development of this electrolyte may lead to practical applications for Li metal anode in rechargeable batteries. The fundamental mechanisms behind the high rate ion exchange and stability of the electrolytes also shine light on the stability of other electrochemical systems.« less

  12. The bursts of high energy events observed by the telescope array surface detector

    NASA Astrophysics Data System (ADS)

    Abbasi, R. U.; Abe, M.; Abu-Zayyad, T.; Allen, M.; Anderson, R.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Fujii, T.; Fukushima, M.; Goto, T.; Hanlon, W.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kishigami, S.; Kitamura, S.; Kitamura, Y.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuda, T.; Matsuyama, T.; Matthews, J. N.; Minamino, M.; Mukai, K.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, T.; Nonaka, T.; Nozato, A.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Okuda, T.; Ono, M.; Onogi, R.; Oshima, A.; Ozawa, S.; Park, I. H.; Pshirkov, M. S.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Saito, K.; Saito, Y.; Sakaki, N.; Sakurai, N.; Sampson, A. L.; Scott, L. M.; Sekino, K.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Shin, H. S.; Smith, J. D.; Sokolsky, P.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzawa, T.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Vasiloff, G.; Wong, T.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.

    2017-08-01

    The Telescope Array (TA) experiment is designed to detect air showers induced by ultra high energy cosmic rays. The TA ground Surface particle Detector (TASD) observed several short-time bursts of air shower like events. These bursts are not likely due to chance coincidence between single shower events. The expectation of chance coincidence is less than 10-4 for five-year's observation. We checked the correlation between these bursts of events and lightning data, and found evidence for correlations in timing and position. Some features of the burst events are similar to those of a normal cosmic ray air shower, and some are not. On this paper, we report the observed bursts of air shower like events and their correlation with lightning.

  13. High infant mortality rate, high total fertility rate and very low female literacy in selected African countries.

    PubMed

    Susuman, A Sathiya; Chialepeh, Wilson N; Bado, Aristide; Lailulo, Yishak

    2016-02-01

    This study focused on the top 10 selected African countries with key interventions such as high infant mortality rate, high total fertility rate and female literacy rate. The World Bank's 2013 data were used. Descriptive analyses were performed. Findings show that Sierra Leone (107.2), Angola (102) and Central Africa Republic (96.1) reported the highest infant mortality rate per 1000 live births. The total fertility rates in Niger (7.6), Mali (6.8) and Somalia (6.6) were higher than other comparable countries. Health care service providers need to pay more attention during pregnancy periods, improve number of field visits, identify pregnant women and promote 100% antenatal care if this is done practically, these countries will reduce and ultimately eliminate infant mortality. © 2015 the Nordic Societies of Public Health.

  14. Integrating GPS with GLONASS for high-rate seismogeodesy

    NASA Astrophysics Data System (ADS)

    Geng, Jianghui; Jiang, Peng; Liu, Jingnan

    2017-04-01

    High-rate GPS is a precious seismogeodetic tool to capture coseismic displacements unambiguously and usually improved by sidereal filtering to mitigate multipath effects dominating the periods of tens of seconds to minutes. We further introduced GLONASS (Globalnaya navigatsionnaya sputnikovaya sistema) data into high-rate GPS to deliver over 2000 24 h displacements at 99 stations in Europe. We find that the major displacement errors induced by orbits and atmosphere on the low-frequency band that are not characterized by sidereal repeatabilities can be amplified markedly by up to 40% after GPS sidereal filtering. In contrast, integration with GLONASS can reduce the noise of high-rate GPS significantly and near uniformly over the entire frequency band, especially for the north components by up to 40%, suggesting that this integration is able to mitigate more errors than only multipath within high-rate GPS. Integrating GPS with GLONASS outperforms GPS sidereal filtering substantially in ameliorating displacement noise by up to 60% over a wide frequency band (e.g., 2 s-0.5 days) except a minor portion between 100 and 1000 s. High-rate multi-GNSS (Global Navigation Satellite System) can be enhanced further by sidereal filtering, which should however be carefully implemented to avoid adverse complications of the noise spectrum of displacements.

  15. Preliminary analysis on faint luminous lightning events recorded by multiple high speed cameras

    NASA Astrophysics Data System (ADS)

    Alves, J.; Saraiva, A. V.; Pinto, O.; Campos, L. Z.; Antunes, L.; Luz, E. S.; Medeiros, C.; Buzato, T. S.

    2013-12-01

    The objective of this work is the study of some faint luminous events produced by lightning flashes that were recorded simultaneously by multiple high-speed cameras during the previous RAMMER (Automated Multi-camera Network for Monitoring and Study of Lightning) campaigns. The RAMMER network is composed by three fixed cameras and one mobile color camera separated by, in average, distances of 13 kilometers. They were located in the Paraiba Valley (in the cities of São José dos Campos and Caçapava), SP, Brazil, arranged in a quadrilateral shape, centered in São José dos Campos region. This configuration allowed RAMMER to see a thunderstorm from different angles, registering the same lightning flashes simultaneously by multiple cameras. Each RAMMER sensor is composed by a triggering system and a Phantom high-speed camera version 9.1, which is set to operate at a frame rate of 2,500 frames per second with a lens Nikkor (model AF-S DX 18-55 mm 1:3.5 - 5.6 G in the stationary sensors, and a lens model AF-S ED 24 mm - 1:1.4 in the mobile sensor). All videos were GPS (Global Positioning System) time stamped. For this work we used a data set collected in four RAMMER manual operation days in the campaign of 2012 and 2013. On Feb. 18th the data set is composed by 15 flashes recorded by two cameras and 4 flashes recorded by three cameras. On Feb. 19th a total of 5 flashes was registered by two cameras and 1 flash registered by three cameras. On Feb. 22th we obtained 4 flashes registered by two cameras. Finally, in March 6th two cameras recorded 2 flashes. The analysis in this study proposes an evaluation methodology for faint luminous lightning events, such as continuing current. Problems in the temporal measurement of the continuing current can generate some imprecisions during the optical analysis, therefore this work aim to evaluate the effects of distance in this parameter with this preliminary data set. In the cases that include the color camera we analyzed the RGB

  16. Composition and meteorological changes associated with a strong stratospheric intrusion event in the Canadian High Arctic

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaoyi; Strong, Kimberly; Conway, Stephanie; Tarasick, David; Osman, Mohammed; Richter, Andreas; Blechschmidt, Anne; Manney, Gloria

    2015-04-01

    Stratosphere-troposphere exchange (STE) provides a mechanism for trace gas transport between the lower stratosphere and the troposphere. Intense downward stratospheric intrusions may significantly affect the oxidizing capacity of the troposphere. Most STE events occur in tropical and mid-latitude regions, with less known about STE in the polar regions. In this work, we present an observation and modelling study of a strong stratospheric intrusion in the high Arctic (Eureka, 80°N) in March 2013, which led to an increase of total ozone and BrO columns observed by both ground-based and satellite instruments. The meteorological conditions for this event were similar to those observed for STEs associated with cold fronts. Before the cold front arrived at Eureka, the surface temperature first increased from -25.3°C (25 March 13:00 UTC) to -14.5°C (27 March 20:00 UTC) and then dropped to -36.4°C (29 March 6:00 UTC) after the front passed by. Meanwhile, the ground-level pressure decreased from 103.8 kPa to 101.8 kPa, then rose back to 102.6 kPa. Ozonesonde data (27 March 23:15 UTC) showed unusually high ozone (>100 ppbv) above ~3 km altitude, while the relative humidity profile indicated that the airmass was of stratospheric origin (very low relative humidity). The thermal tropopause height was ~9 km, based on a uniform lapse rate of 3.9 K/km from surface to 9 km. From ECMWF Interim data, the airmass with high relative potential vorticity (4 pvu) extended down to 3 km. In addition, HYSPLIT model ensemble back-trajectories show a clear Rossby wave signature in the upper troposphere during this event, which could explain the intrusion. However, there are no strong downwelling layers along the trajectories, which indicates that the intrusion may have occurred close to Eureka. Trace gas composition data from three ground-based spectrometers and the GOME-2 satellite instrument are presented in this work. Ozone vertical column densities (VCDs) measured by two Zenith

  17. High Strain Rate Behavior of Polymer Matrix Composites Analyzed

    NASA Technical Reports Server (NTRS)

    Goldberg, Robert K.; Roberts, Gary D.

    2001-01-01

    Procedures for modeling the high-speed impact of composite materials are needed for designing reliable composite engine cases that are lighter than the metal cases in current use. The types of polymer matrix composites that are likely to be used in such an application have a deformation response that is nonlinear and that varies with strain rate. To characterize and validate material models that could be used in the design of impactresistant engine cases, researchers must obtain material data over a wide variety of strain rates. An experimental program has been carried out through a university grant with the Ohio State University to obtain deformation data for a representative polymer matrix composite for strain rates ranging from quasi-static to high rates of several hundred per second. This information has been used to characterize and validate a constitutive model that was developed at the NASA Glenn Research Center.

  18. Scaling A Moment-Rate Function For Small To Large Magnitude Events

    NASA Astrophysics Data System (ADS)

    Archuleta, Ralph; Ji, Chen

    2017-04-01

    Since the 1980's seismologists have recognized that peak ground acceleration (PGA) and peak ground velocity (PGV) scale differently with magnitude for large and moderate earthquakes. In a recent paper (Archuleta and Ji, GRL 2016) we introduced an apparent moment-rate function (aMRF) that accurately predicts the scaling with magnitude of PGA, PGV, PWA (Wood-Anderson Displacement) and the ratio PGA/2πPGV (dominant frequency) for earthquakes 3.3 ≤ M ≤ 5.3. This apparent moment-rate function is controlled by two temporal parameters, tp and td, which are related to the time for the moment-rate function to reach its peak amplitude and the total duration of the earthquake, respectively. These two temporal parameters lead to a Fourier amplitude spectrum (FAS) of displacement that has two corners in between which the spectral amplitudes decay as 1/f, f denotes frequency. At higher or lower frequencies, the FAS of the aMRF looks like a single-corner Aki-Brune omega squared spectrum. However, in the presence of attenuation the higher corner is almost certainly masked. Attempting to correct the spectrum to an Aki-Brune omega-squared spectrum will produce an "apparent" corner frequency that falls between the double corner frequency of the aMRF. We reason that the two corners of the aMRF are the reason that seismologists deduce a stress drop (e.g., Allmann and Shearer, JGR 2009) that is generally much smaller than the stress parameter used to produce ground motions from stochastic simulations (e.g., Boore, 2003 Pageoph.). The presence of two corners for the smaller magnitude earthquakes leads to several questions. Can deconvolution be successfully used to determine scaling from small to large earthquakes? Equivalently will large earthquakes have a double corner? If large earthquakes are the sum of many smaller magnitude earthquakes, what should the displacement FAS look like for a large magnitude earthquake? Can a combination of such a double-corner spectrum and random

  19. Study of High Strain Rate Response of Composites

    NASA Technical Reports Server (NTRS)

    Gilat, Amos

    2003-01-01

    The objective of the research was to continue the experimental study of the effect of strain rate on mechanical response (deformation and failure) of epoxy resins and carbon fibers/epoxy matrix composites, and to initiate a study of the effects of temperature by developing an elevated temperature test. The experimental data provide the information needed for NASA scientists for the development of a nonlinear, rate dependent deformation and strength models for composites that can subsequently be used in design. This year effort was directed into testing the epoxy resin. Three types of epoxy resins were tested in tension and shear at various strain rates that ranges from 5 x 10(exp -5), to 1000 per second. Pilot shear experiments were done at high strain rate and an elevated temperature of 80 C. The results show that all, the strain rate, the mode of loading, and temperature significantly affect the response of epoxy.

  20. The Class of 2002 Four-Year Longitudinal Report and 2001-2002 Event Dropout Rates.

    ERIC Educational Resources Information Center

    Waddington, Susan

    This study examined the progress toward school completion of students who entered ninth grade in fall 1998 and were scheduled to graduate on time in spring 2002 after 4 years of high school, offering outcomes for the class as a whole and for specific groups of students categorized by gender, native language, race/ethnicity, and immigrant status.…

  1. Current Perspectives on Arthroplasty in Systemic Lupus Erythematosus: Rates, Outcomes, and Adverse Events.

    PubMed

    Kasturi, Shanthini; Goodman, Susan

    2016-09-01

    Systemic lupus erythematosus (SLE) is a chronic debilitating condition with significant impact on the musculoskeletal system. Arthroplasty may be indicated for damage related to active lupus or its treatment. As therapies for SLE have advanced, morbidity and mortality have declined, while the rate of joint replacement has increased. The age of SLE patients undergoing arthroplasty is increasing, and the indication for surgery is evolving-while avascular necrosis was previously the predominant indication for arthroplasty, osteoarthritis now accounts for a larger proportion of surgeries. Pain and functional outcomes of arthroplasty in SLE patients are comparable to those of the general population with osteoarthritis, but lupus remains an independent risk factor for post-hip arthroplasty complications and mortality. Further research is needed to characterize the impact of lupus disease activity and severity on arthroplasty outcomes.

  2. Application of stochastic discrete event system framework for detection of induced low rate TCP attack.

    PubMed

    Barbhuiya, F A; Agarwal, Mayank; Purwar, Sanketh; Biswas, Santosh; Nandi, Sukumar

    2015-09-01

    TCP is the most widely accepted transport layer protocol. The major emphasis during the development of TCP was its functionality and efficiency. However, not much consideration was given on studying the possibility of attackers exploiting the protocol, which has lead to several attacks on TCP. This paper deals with the induced low rate TCP attack. Since the attack is relatively new, only a few schemes have been proposed to mitigate it. However, the main issues with these schemes are scalability, change in TCP header, lack of formal frameworks, etc. In this paper, we have adapted the stochastic DES framework for detecting the attack, which addresses most of these issues. We have successfully deployed and tested the proposed DES based IDS on a test bed. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Reconstruction of high frame rate image sequences in biomechanical related areas.

    PubMed

    Costa, Monica; Soares, Salviano; Barroso, Joao

    2010-01-01

    Regular video cameras shoot normally at 25/30 frames per second (fps). Actually there are available in the market equipments that allow us to acquire video at 1.000.000 fps. When we observe a video sequence it becomes noticeable that great part of the information remains unchanged regardless of the bit rate or frame rate used. One origin of discontinuity in video signals is directly related to movement. Several areas use high frame rate images to analyze and comprehend certain events or effects, biomechanical engineering is one of them. Biomechanics engineering studies the mechanics of a living body, especially the forces exerted by muscles and gravity on the skeletal structure. Some examples are athlete assessment, were images are capture and then the acquired parameters are analyzed. This article describes a new methodology to decrease the space needed to store high frame rate image sequences in the specific case of biomechanical related areas.

  4. A comparison of slip rate, recurrence interval, and slip per event on several well-characterized faults (Invited)

    NASA Astrophysics Data System (ADS)

    Weldon, R. J.; Lippoldt, R. C.; Scharer, K.; Streig, A. R.; Langridge, R. M.; Madugo, C. M.; Biasi, G. P.; Dawson, T. E.

    2013-12-01

    Rapid growth in the application of LiDAR and other modern geodetic techniques has led to an explosion in the number of micro-geomorphic offsets along faults that can be interpreted as displacement in one or several earthquakes. As a result of this new data there are an increasing number of places along faults for which data are available for the slip rate (based on the dated offset of a feature that is old enough to average out the seismic cycle), recurrence interval (based on a representative number of dated paleo-earthquakes), and slip per event (based on an adequate sample of micro-geomorphic or 3D-excavated offsets). Because these three datasets are largely independent, but related by accumulation and release of strain across the fault, comparing them can provide insight into how faults balance size and frequency of earthquakes. We discuss several examples of faults with closely co-located slip rate, recurrence interval, and slip per event data, including the Ana River fault, a small normal fault in Central Oregon, and portions of the San Andreas fault, the principal plate boundary fault in California. The Ana River fault offsets more than 11 Pleistocene shorelines different amounts that we have measured using a combination of LiDAR, ground-based surveying, and a DEM generated from a USGS topographic map with 5 foot contours. The ages of ~10 paleo-earthquakes are determined from trenches and other exposures into deep-water lacustrine deposits that contain ~50 dated volcanic ashes. The long-term slip rate, 0.05 mm/yr, is known from the total offset of dated late Pliocene basalts. We also use new data from the Santa Cruz segment of the northern San Andreas fault (NSAF) and the southern San Andreas fault (SSAF: Parkfield to Bombay Beach). On the NSAF, earthquakes in 1838, 1890, and 1906 have a total slip of 4 - 6 m while the slip rate (17 mm/yr) suggests it would take 2 - 3 centuries to accumulate this much strain. Data for the SSAF, which have recently been

  5. Measuring the Transition Rates of Coalescence Events during Double Phase Separation in Microgravity.

    PubMed

    Oprisan, Ana; Garrabos, Yves; Lecoutre, Carole; Beysens, Daniel

    2017-07-06

    Phase transition is a ubiquitous phenomenon in nature, science and technology. In general, the phase separation from a homogeneous phase depends on the depth of the temperature quench into the two-phase region. Earth's gravity masks the details of phase separation phenomena, which is why experiments were performed under weightlessness. Under such conditions, the pure fluid sulphur hexafluoride (SF 6 ) near its critical point also benefits from the universality of phase separation behavior and critical slowing down of dynamics. Initially, the fluid was slightly below its critical temperature with the liquid matrix separated from the vapor phase. A 0.2 mK temperature quench further cooled down the fluid and produced a double phase separation with liquid droplets inside the vapor phase and vapor bubbles inside the liquid matrix, respectively. The liquid droplets and the vapor bubbles respective distributions were well fitted by a lognormal function. The evolution of discrete bins of different radii allowed the derivation of the transition rates for coalescence processes. Based on the largest transition rates, two main coalescence mechanisms were identified: (1) asymmetric coalescences between one small droplet of about 20 μ m and a wide range of larger droplets; and (2) symmetric coalescences between droplets of large and similar radii. Both mechanisms lead to a continuous decline of the fraction of small radii droplets and an increase in the fraction of the large radii droplets. Similar coalescence mechanisms were observed for vapor bubbles. However, the mean radii of liquid droplets exhibits a t 1 / 3 evolution, whereas the mean radii of the vapor bubbles exhibit a t 1 / 2 evolution.

  6. The application of "natural" growth rates of Heterostegina depressa to infer timing of reproduction events

    NASA Astrophysics Data System (ADS)

    Eder, Wolfgang; Julia, Woeger; Kinoshita, Shunichi; Hohenegger, Johann; Briguglio, Antonino

    2017-04-01

    To explore applicability of the natural laboratory approach (sensu Hohenegger) on population dynamic studies of recent larger benthic foraminifera, this relatively new experimental method has been applied on Heterostegina depressa populations from Sesoko Jima, NW Okinawa, Japan. It is used to gain an averaged chamber and diameter building rate, as well as the average longevity of H. depressa based on monthly samplings at fixed sampling stations. Samples were collected by SCUBA in 16 monthly intervals around 20 and 50 meters water depth, wherefrom live populations were dried and investigated by microCT. The specimens were measured regarding chamber number and maximum diameter. This biometric data has been tested for the presence of multiple generations of H. depressa megalospheres. In case of skewed or bimodal frequency distributions, they were decomposed into normally distributed components. Means and standard deviations of each component of every month were extracted and could be used to calculate the maximum values of chamber number and diameter for all sampling intervals. Based on these maximal values, the natural chamber/diameter growth rate was fitted by Michaelis-Menten functions. By inversion of this growth functions the birthdate of every specimen was calculated. Frequency diagrams of these dates reveal a continuous background reproduction throughout the year, yet show distinct reproduction peaks in late spring and late autumn. Further, sinusoidal regression analysis support these two main reproduction cycles, one short-term cycle 70 days and a one long-term cycles around 180 days. Surprisingly, similar cycles have been found in different studies on volumetric growth of larger benthic foraminifera.

  7. Effect of copper and aluminium on the event rate of cosmic ray muons at ground level in Bangi, Malaysia

    NASA Astrophysics Data System (ADS)

    Altameemi, Rasha N. I.; Gopir, G.

    2016-11-01

    In this study we determine the effect of aluminium (Al) and copper (Cu) shielding on the event rate of cosmic ray muons at ground level. The experiment was performed at Bangi in Malaysia with coordinates of 101.78° E, 2.92° N and elevation 30 m above sea level. Measurements were made along the vertical direction using muon telescopes (MTs) of parallel Geiger-Muller (GM) tubes with metal sheets above the MTs of up to 2.4 cm for Al and 2.7 cm for Cu. For these ranges of metal thicknesses, we find that the muon count rates increase linearly with the increase in metal thicknesses. The observed increase rate values are (0.18 ± 0.10) cm-1 and (0.26 ± 0.10)cm-1 for Al and Cu, respectively, with the larger value for Cu as expected from its higher atomic number and density. This indicates that for this thickness range, only the lower region of the Rossi curve is observed, with incoming cosmic ray muons producing charged particles in the metal layers, resulting in shower events or electromagnetic cascade. Thus, for this range of layer thickness, both aluminium and copper are not suitable to be used as shielding materials for ground level cosmic ray muons.

  8. THE AMERICAN HIGH SCHOOL GRADUATION RATE: TRENDS AND LEVELS*

    PubMed Central

    Heckman, James J.; LaFontaine, Paul A.

    2009-01-01

    This paper applies a unified methodology to multiple data sets to estimate both the levels and trends in U.S. high school graduation rates. We establish that (a) the true rate is substantially lower than widely used measures; (b) it peaked in the early 1970s; (c) majority/minority differentials are substantial and have not converged for 35 years; (d) lower post-1970 rates are not solely due to increasing immigrant and minority populations; (e) our findings explain part of the slowdown in college attendance and rising college wage premiums; and (f) widening graduation differentials by gender help explain increasing male-female college attendance gaps. PMID:20625528

  9. High-Strain-Rate Compression Testing of Ice

    NASA Technical Reports Server (NTRS)

    Shazly, Mostafa; Prakash, Vikas; Lerch, Bradley A.

    2006-01-01

    In the present study a modified split Hopkinson pressure bar (SHPB) was employed to study the effect of strain rate on the dynamic material response of ice. Disk-shaped ice specimens with flat, parallel end faces were either provided by Dartmouth College (Hanover, NH) or grown at Case Western Reserve University (Cleveland, OH). The SHPB was adapted to perform tests at high strain rates in the range 60 to 1400/s at test temperatures of -10 and -30 C. Experimental results showed that the strength of ice increases with increasing strain rates and this occurs over a change in strain rate of five orders of magnitude. Under these strain rate conditions the ice microstructure has a slight influence on the strength, but it is much less than the influence it has under quasi-static loading conditions. End constraint and frictional effects do not influence the compression tests like they do at slower strain rates, and therefore the diameter/thickness ratio of the samples is not as critical. The strength of ice at high strain rates was found to increase with decreasing test temperatures. Ice has been identified as a potential source of debris to impact the shuttle; data presented in this report can be used to validate and/or develop material models for ice impact analyses for shuttle Return to Flight efforts.

  10. Online aging study of a high rate MRPC

    NASA Astrophysics Data System (ADS)

    Wang, Jie; Wang, Yi; Feng, S. Q.; Xie, Bo; Lv, Pengfei; Wang, Fuyue; Guo, Baohong; Han, Dong; Li, Yuanjing

    2016-05-01

    With the constant increase of accelerator luminosity, the rate requirements of MRPC detectors have become very important, and the aging characteristics of the detector have to be studied meticulously. An online aging test system has been set up in our lab, and in this paper the setup of the system is described and the performance stability of a high-rate MRPC studied over a long running time under a high luminosity environment. The high rate MRPC was irradiated by X-rays for 36 days and the accumulated charge density reached 0.1 C/cm2. No obvious performance degradation was observed for the detector. Supported by National Natural Science Foundation of China (11420101004, 11461141011, 11275108), Ministry of Science and Technology (2015CB856905)

  11. Semi-solid electrodes having high rate capability

    DOEpatents

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2015-11-10

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode, a semi-solid cathode that includes a suspension of an active material and a conductive material in a liquid electrolyte, and an ion permeable membrane disposed between the anode and the cathode. The semi-solid cathode has a thickness in the range of about 250 .mu.m-2,500 .mu.m, and the electrochemical cell has an area specific capacity of at least 5 mAh/cm.sup.2 at a C-rate of C/2.

  12. High strain rate superplasticity in metals and composites

    SciTech Connect

    Nieh, T.G.; Wadsworth, J.; Higashi, K.

    1993-07-01

    Superplastic behavior at very high strain rates (at or above 1 s{sup {minus}1}) in metallic-based materials is an area of increasing interest. The phenomenon has been observed quite extensively in metal alloys, metal-matrix composites (MMC), and mechanically-alloyed (MA) materials. In the present paper, experimental results on high strain rate behavior in 2124 Al-based materials, including Zr-modified 2124, SiC-reinforced 2124, MA 2124, and MA 2124 MMC, are presented. Except for the required fine grain size, details of the structural requirements of this phenomenon are not yet understood. Despite this, a systematic approach to produce high strain rate superplasticity (HSRS) in metallic materials is given in this paper. Evidences indicate that the presence of a liquid phase, or a low melting point region, at boundary interfaces is responsible for HSRS.

  13. Semi-solid electrodes having high rate capability

    SciTech Connect

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2016-07-05

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode, a semi-solid cathode that includes a suspension of an active material and a conductive material in a liquid electrolyte, and an ion permeable membrane disposed between the anode and the cathode. The semi-solid cathode has a thickness in the range of about 250 .mu.m-2,500 .mu.m, and the electrochemical cell has an area specific capacity of at least 5 mAh/cm.sup.2 at a C-rate of C/2.

  14. Exploring similarities and differences in hospital adverse event rates between Norway and Sweden using Global Trigger Tool

    PubMed Central

    Risberg, Madeleine Borgstedt; Haugen, Marion; Lindstrøm, Jonas Christoffer; Nylén, Urban; Rutberg, Hans; Michael, Soop

    2017-01-01

    Objectives In this paper, we explore similarities and differences in hospital adverse event (AE) rates between Norway and Sweden by reviewing medical records with the Global Trigger Tool (GTT). Design All acute care hospitals in both countries performed medical record reviews, except one in Norway. Records were randomly selected from all eligible admissions in 2013. Eligible admissions were patients 18 years of age or older, undergoing care with an in-hospital stay of at least 24 hours, excluding psychiatric and care and rehabilitation. Reviews were done according to GTT methodology. Setting Similar contexts for healthcare and similar socioeconomic and demographic characteristics have inspired the Nordic countries to exchange experiences from measuring and monitoring quality and patient safety in healthcare. The co-operation has promoted the use of GTT to monitor national and local rates of AEs in hospital care. Participants 10 986 medical records were reviewed in Norway and 19 141 medical records in Sweden. Results No significant difference between overall AE rates was found between the two countries. The rate was 13.0% (95% CI 11.7% to 14.3%) in Norway and 14.4% (95% CI 12.6% to 16.3%) in Sweden. There were significantly higher AE rates of surgical complications in Norwegian hospitals compared with Swedish hospitals. Swedish hospitals had significantly higher rates of pressure ulcers, falls and ‘other’ AEs. Among more severe AEs, Norwegian hospitals had significantly higher rates of surgical complications than Swedish hospitals. Swedish hospitals had significantly higher rates of postpartum AEs. Conclusions The level of patient safety in acute care hospitals, as assessed by GTT, was essentially the same in both countries. The differences between the countries in the rates of several types of AEs provide new incentives for Norwegian and Swedish governing bodies to address patient safety issues. PMID:28320786

  15. 5 CFR Appendix A to Subpart F of... - List of Events for Which Inclusion of NAFI Service May Affect the Rate of Annuity Payable

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false List of Events for Which Inclusion of NAFI Service May Affect the Rate of Annuity Payable A Appendix A to Subpart F of Part 847... of Part 847—List of Events for Which Inclusion of NAFI Service May Affect the Rate of Annuity Payable...

  16. High-Performance Monitoring Architecture for Large-Scale Distributed Systems Using Event Filtering

    NASA Technical Reports Server (NTRS)

    Maly, K.

    1998-01-01

    Monitoring is an essential process to observe and improve the reliability and the performance of large-scale distributed (LSD) systems. In an LSD environment, a large number of events is generated by the system components during its execution or interaction with external objects (e.g. users or processes). Monitoring such events is necessary for observing the run-time behavior of LSD systems and providing status information required for debugging, tuning and managing such applications. However, correlated events are generated concurrently and could be distributed in various locations in the applications environment which complicates the management decisions process and thereby makes monitoring LSD systems an intricate task. We propose a scalable high-performance monitoring architecture for LSD systems to detect and classify interesting local and global events and disseminate the monitoring information to the corresponding end- points management applications such as debugging and reactive control tools to improve the application performance and reliability. A large volume of events may be generated due to the extensive demands of the monitoring applications and the high interaction of LSD systems. The monitoring architecture employs a high-performance event filtering mechanism to efficiently process the large volume of event traffic generated by LSD systems and minimize the intrusiveness of the monitoring process by reducing the event traffic flow in the system and distributing the monitoring computation. Our architecture also supports dynamic and flexible reconfiguration of the monitoring mechanism via its Instrumentation and subscription components. As a case study, we show how our monitoring architecture can be utilized to improve the reliability and the performance of the Interactive Remote Instruction (IRI) system which is a large-scale distributed system for collaborative distance learning. The filtering mechanism represents an Intrinsic component integrated

  17. Flexible high-repetition-rate ultrafast fiber laser

    PubMed Central

    Mao, Dong; Liu, Xueming; Sun, Zhipei; Lu, Hua; Han, Dongdong; Wang, Guoxi; Wang, Fengqiu

    2013-01-01

    High-repetition-rate pulses have widespread applications in the fields of fiber communications, frequency comb, and optical sensing. Here, we have demonstrated high-repetition-rate ultrashort pulses in an all-fiber laser by exploiting an intracavity Mach-Zehnder interferometer (MZI) as a comb filter. The repetition rate of the laser can be tuned flexibly from about 7 to 1100 GHz by controlling the optical path difference between the two arms of the MZI. The pulse duration can be reduced continuously from about 10.1 to 0.55 ps with the spectral width tunable from about 0.35 to 5.7 nm by manipulating the intracavity polarization controller. Numerical simulations well confirm the experimental observations and show that filter-driven four-wave mixing effect, induced by the MZI, is the main mechanism that governs the formation of the high-repetition-rate pulses. This all-fiber-based laser is a simple and low-cost source for various applications where high-repetition-rate pulses are necessary. PMID:24226153

  18. OSCAR experiment high-density network data report: Event 4 - April 21-23, 1981

    SciTech Connect

    Dana, M.T.; Easter, R.C.; Thorp, J.M.

    1984-12-01

    The OSCAR (Oxidation and Scavenging Characteristics of April Rains) experiment, conducted during April 1981, was a cooperative field investigation of wet removal in cyclonic storm systems. The high-density component of OSCAR was located in northeast Indiana and included sequential precipitation chemistry measurements on a 100 by 100 km netwok, as well as airborne air chemistry and cloud chemistry mueasurements, surface air chemistry measurements, and supporting meteorological measurements. Four separate storm events were studied during the experiment. This report summarizes data taken by Pacific Northwest Laboratory (PNL) during the fourth storm event, April 21-23. The report contains the high-density network precipitation chemistry data, air and cloud chemistry data from the two PNL aircraft, and meteorological data for the event, including standard National Weather Service products and radar and rawindsonde data from the event. 3 references, 80 figures, 11 tables.

  19. A method for critical software event execution reliability in high assurance systems

    SciTech Connect

    Kidd, M.E.C.

    1997-03-01

    This paper presents a method for Critical Software Event Execution Reliability (Critical SEER). The Critical SEER method is intended for high assurance software that operates in an environment where transient upsets could occur, causing a disturbance of the critical software