Sample records for fast response instruments

  1. Intercomparison of six fast-response sensors for the eddy-covariance flux measurement of nitrous oxide over agricultural grassland

    NASA Astrophysics Data System (ADS)

    Nemitz, Eiko; Famulari, Daniela; Ibrom, Andreas; Vermeulen, Alex; Hensen, Arjan; van den Bulk, Pim; Loubet, Benjamin; Laville, Patricia; Mammarella, Ivan; Haapanala, Sami; Lohila, Annalea; Laurila, Tuomas; Eva, Rabot; Laborde, Marie; Cowan, Nicholas; Anderson, Margaret; Helfter, Carole

    2015-04-01

    Nitrous oxide (N2O) is the third most important greenhouse gas and its terrestrial budget remains poorly constraint, with bottom up and top down estimates of country emissions often disagreeing by more than a factor of two. Whilst the measurements of the biosphere / atmosphere exchange of CO2 with micrometeorological methods is commonplace, emissions of CH4 and N2O are more commonly measured with enclosure techniques due to limitations in fast-response sensors with good signal-to-noise characteristics. Recent years have seen the development of a range of instruments based on optical spectroscopy. This started in the early 1990s with instruments based on lead salt lasers, which had temperamental long-term characteristics. More recent developments in quantum cascade lasers has lead to increasingly stable instruments, initially based on pulsed, later on continuous wave lasers. Within the context of the European FP7 Infrastructure Project InGOS ('Integrated non-CO2 Greenhouse gas Observing System'), we conducted an intercomparison of six fast response sensors for N2O: three more or less identical instruments based on off-axis Integrated Cavity Optical Spectrocopy (ICOS) (Los Gatos Research Inc.) and three instruments based on quantum cascade laser absorption spectrometry (Aerodyne Research Inc.): one older generation pulsed instrument (p-QCL) and two of the latest generation of compact continuous wave instruments (cw-QCL), operating at two different wavelengths. One of the ICOS instruments was operated with an inlet drier. In addition, the campaign was joined by a relaxed eddy-accumulation system linked to a FTIR spectrometer (Ecotech), a gradient system based on a home-built slower QCL (INRA Orleans) and a fast chamber system. Here we present the results of the study and a detailed examination of the various corrections and errors of the different instruments. Overall, with the exception of the older generation QCL, the average fluxes based on the different fast-response instruments agreed within +/- 7.4%, although fluxes were moderate. The cw-QCL systems showed somewhat better signal-to-noise characteristics and a lower flux detection limit than the ICOS analysers. Intriguingly, there seemed to be some minor differences between the ICOS instruments which showed cross sensitivities to CO to varying degree. Overall the study demonstrates, that, while not cheap, both the ICOS-based instruments and the cw-QCLs are suitable for the measurement of even moderate N2O fluxes.

  2. A compact, fast ozone UV photometer and sampling inlet for research aircraft

    NASA Astrophysics Data System (ADS)

    Gao, R. S.; Ballard, J.; Watts, L. A.; Thornberry, T. D.; Ciciora, S. J.; McLaughlin, R. J.; Fahey, D. W.

    2012-05-01

    In situ measurements of atmospheric ozone (O3) are performed routinely from many research aircraft platforms. The most common technique depends on the strong absorption of ultraviolet (UV) light by ozone. As atmospheric science advances to the widespread use of unmanned aircraft systems (UASs), there is an increasing requirement for minimizing instrument space, weight, and power while maintaining instrument accuracy, precision and time response. The design and use of a new, dual-beam, polarized, UV photometer instrument for in situ O3 measurements is described. The instrument has a fast sampling rate (2 Hz), high accuracy (3%), and precision (1.1 × 1010 O3 molecules cm-3). The size (36 l), weight (18 kg), and power (50-200 W) make the instrument suitable for many UAS and other airborne platforms. Inlet and exhaust configurations are also described for ambient sampling in the troposphere and lower stratosphere (1000-50 mb) that optimize the sample flow rate to increase time response while minimizing loss of precision due to induced turbulence in the sample cell. In-flight and laboratory intercomparisons with existing O3 instruments show that measurement accuracy is maintained in flight.

  3. R and D program for core instrumentation improvements devoted for French sodium fast reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jeannot, J. P.; Rodriguez, G.; Jammes, C.

    2011-07-01

    Under the framework of French R and D studies for Generation IV reactors and more specifically for sodium-cooled fast reactors (SFR); the CEA, EDF and AREVA have launched a joint coordinated research programme. This paper deals with the R and D sets out to achieve better inspection, maintenance, availability and decommissioning. In particular the instrumentation requirements for core monitoring and detection in the case of accidental events. Requirements mainly involve diversifying the means of protection and improving instrumentation performance in terms of responsiveness and sensitivity. Operation feedback from the Phenix and Superphenix prototype reactors and studies, carried out within themore » scope of the EFR projects, has been used to define the needs for instrumentation enhancement. (authors)« less

  4. A Fast Response Capability within NOAA/NOS/CO-OPS

    DTIC Science & Technology

    2007-01-01

    A Fast Response Capability within NOAA/NOS/CO-OPS P. B. Burke NOAA/National Ocean Service/CO-OPS 1305 East-West Hwy. Silver Spring, MD 20910...USA pat.burke@noaa.gov T. Graff NOAA/National Ocean Service/CO-OPS 1305 East-West Hwy. Silver Spring, MD 20910 USA tammy.graff@noaa.gov... flotation hull, an instrumentation tower mounted atop the hull and a current meter mount with a mooring attachment. The triangular tower housed two

  5. UFFO/ Lomonosov: The Payload for the Observation of Early Photons from Gamma Ray Bursts

    NASA Astrophysics Data System (ADS)

    Park, I. H.; Panasyuk, M. I.; Reglero, V.; Chen, P.; Castro-Tirado, A. J.; Jeong, S.; Bogomolov, V.; Brandt, S.; Budtz-Jørgensen, C.; Chang, S.-H.; Chang, Y. Y.; Chen, C.-R.; Chen, C.-W.; Choi, H. S.; Connell, P.; Eyles, C.; Gaikov, G.; Garipov, G.; Huang, J.-J.; Huang, M.-H. A.; Jeong, H. M.; Kim, J. E.; Kim, M. B.; Kim, S.-W.; Lee, H. K.; Lee, J.; Lim, H.; Lin, C.-Y.; Liu, T.-C.; Nam, J. W.; Petrov, V.; Ripa, J.; Rodrigo, J. M.; Svertilov, S.; Wang, M.-Z.; Yashin, I.

    2018-02-01

    The payload of the UFFO (Ultra-Fast Flash Observatory)-pathfinder now onboard the Lomonosov spacecraft (hereafter UFFO/ Lomonosov) is a dedicated instrument for the observation of GRBs. Its primary aim is to capture the rise phase of the optical light curve, one of the least known aspects of GRBs. Fast response measurements of the optical emission of GRB will be made by a Slewing Mirror Telescope (SMT), a key instrument of the payload, which will open a new frontier in transient studies by probing the early optical rise of GRBs with a response time in seconds for the first time. The SMT employs a rapidly slewing mirror to redirect the optical axis of the telescope to a GRB position prior determined by the UFFO Burst Alert Telescope (UBAT), the other onboard instrument, for the observation and imaging of X-rays. UFFO/Lomonosov was launched successfully from Vostochny, Russia on April 28, 2016, and will begin GRB observations after completion of functional checks of the Lomonosov spacecraft. The concept of early GRB photon measurements with UFFO was reported in 2012. In this article, we will report in detail the first mission, UFFO/Lomonosov, for the rapid response to GRB observations.

  6. Effects of Gas-Wall Partitioning in Teflon Tubing, Instrumentation and Other Materials on Time-Resolved Measurements of Gas-Phase Organic Compounds

    NASA Astrophysics Data System (ADS)

    Pagonis, D.; Deming, B.; Krechmer, J. E.; De Gouw, J. A.; Jimenez, J. L.; Ziemann, P. J.

    2017-12-01

    Recently it has been shown that gas-phase organic compounds partition to and from the walls of Teflon environmental chambers. This process is fast, reversible, and can be modeled as absorptive partitioning. Here these studies were extended to investigate gas-wall partitioning inside Teflon tubing by introducing step function changes in the concentration of compounds being sampled and measuring the delay in the response of a proton transfer reaction-mass spectrometer (PTR-MS). We find that these delays are significant for compounds with a saturation vapor concentration (c*) below 106 μg m-3, and that the Teflon tubing and the PTR-MS both contribute to the delays. Tubing delays range from minutes to hours under common sampling conditions and can be accurately predicted by a simple chromatography model across a range of tubing lengths and diameters, flow rates, compound functional groups, and c*. This method also allows one to determine the volatility-dependent response function of an instrument, which can be convolved with the output of the tubing model to correct for delays in instrument response time for these "sticky" compounds. This correction is expected to be of particular interest to researchers utilizing and developing chemical ionization mass spectrometry (CIMS) techniques, since many of the multifunctional organic compounds detected by CIMS show significant tubing and instrument delays. These results also enable better design of sampling systems, in particular when fast instrument response is needed, such as for rapid transients, aircraft, or eddy covariance measurements. Additional results presented here extend this method to quantify the relative sorptive capacities for other commonly used tubing materials, including PFA, FEP, PTFE, PEEK, glass, copper, stainless steel, and passivated steel.

  7. Vertical profiles of ozone, carbon monoxide, and dew-point temperature obtained during GTE/CITE 1, October-November 1983. [Chemical Instrumentation Test and Evaluation

    NASA Technical Reports Server (NTRS)

    Fishman, Jack; Gregory, Gerald L.; Sachse, Glen W.; Beck, Sherwin M.; Hill, Gerald F.

    1987-01-01

    A set of 14 pairs of vertical profiles of ozone and carbon monoxide, obtained with fast-response instrumentation, is presented. Most of these profiles, which were measured in the remote troposphere, also have supporting fast-response dew-point temperature profiles. The data suggest that the continental boundary layer is a source of tropospheric ozone, even in October and November, when photochemical activity should be rather small. In general, the small-scale vertical variability between CO and O3 is in phase. At low latitudes this relationship defines levels in the atmosphere where midlatitude air is being transported to lower latitudes, since lower dew-point temperatures accompany these higher CO and O3 concentrations. A set of profiles which is suggestive of interhemispheric transport is also presented. Independent meteorological analyses support these interpretations.

  8. Acoustic Sensing of Ocean Turbulence

    DTIC Science & Technology

    1991-12-01

    quantities and of fast varying quantities, requiring high spatial resolution, fast response sensors and stable observation platforms. A classical approach to...with this type of sensor . Moum et.al. [Ref.l0] performed upper ocean observations with this instrument where they were able to 60 characterize the fine...platform orientation using the 3 axis accelerometer as tiltmeters . E. NON-ACOUSTIC DATA The non-acoustic channels on the CDV package are: 3 component

  9. FastBit: Interactively Searching Massive Data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Kesheng; Ahern, Sean; Bethel, E. Wes

    2009-06-23

    As scientific instruments and computer simulations produce more and more data, the task of locating the essential information to gain insight becomes increasingly difficult. FastBit is an efficient software tool to address this challenge. In this article, we present a summary of the key underlying technologies, namely bitmap compression, encoding, and binning. Together these techniques enable FastBit to answer structured (SQL) queries orders of magnitude faster than popular database systems. To illustrate how FastBit is used in applications, we present three examples involving a high-energy physics experiment, a combustion simulation, and an accelerator simulation. In each case, FastBit significantly reducesmore » the response time and enables interactive exploration on terabytes of data.« less

  10. Abstract - Cooperative Research and Development Agreement between Oxergy, Inc. and National Energy Technology Laboratory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chorpening, Benjamin T.; Kamler, Jonathan

    The Raman Gas Analyzer (RGA) has been demonstrated to have an extremely fast response (<1 second), pressurized, multi-gas analysis capability. All but the noble gases are Raman active, although the Raman interaction is weak. The RGA uses a reflectively lined capillary as the optical cell, providing both a small sample volume for fast gas exchange, and a much greater Raman signal collection than traditional instrument configurations.

  11. Impact of cold climates on vehicle emissions: the cold start air toxics pulse : final report.

    DOT National Transportation Integrated Search

    2016-09-21

    This project measured cold start emissions from four vehicles in winter using fast response instrumentation to accurately measure the : time variation of the cold start emission pulse. Seventeen successful tests were conducted over a temperature rang...

  12. An automated online instrument to quantify aerosol-bound reactive oxygen species (ROS) for ambient measurement and health-relevant aerosol studies

    NASA Astrophysics Data System (ADS)

    Wragg, Francis P. H.; Fuller, Stephen J.; Freshwater, Ray; Green, David C.; Kelly, Frank J.; Kalberer, Markus

    2016-10-01

    The adverse health effects associated with ambient aerosol particles have been well documented, but it is still unclear which aerosol properties are most important for their negative health impact. Some studies suggest the oxidative effects of particle-bound reactive oxygen species (ROS) are potential major contributors to the toxicity of particles. Traditional ROS measurement techniques are labour-intensive, give poor temporal resolution and generally have significant delays between aerosol sampling and ROS analysis. However, many oxidising particle components are reactive and thus potentially short-lived. Thus, a technique to quantify particle-bound ROS online would be beneficial to quantify also the short-lived ROS components. We introduce a new portable instrument to allow online, continuous measurement of particle-bound ROS using a chemical assay of 2'7'-dichlorofluorescein (DCFH) with horseradish peroxidase (HRP), via fluorescence spectroscopy. All components of the new instrument are attached to a containing shell, resulting in a compact system capable of automated continuous field deployment over many hours or days. From laboratory measurements, the instrument was found to have a detection limit of ˜ 4 nmol [H2O2] equivalents per cubic metre (m3) air, a dynamic range up to at least ˜ 2000 nmol [H2O2] equivalents per m3 air and a time resolution of ≤ 12 min. The instrument allows for ˜ 16 h automated measurement if unattended and shows a fast response to changes in concentrations of laboratory-generated oxidised organic aerosol. The instrument was deployed at an urban site in London, and particulate ROS levels of up to 24 nmol [H2O2] equivalents per m3 air were detected with PM2.5 concentrations up to 28 µg m-3. The new and portable Online Particle-bound ROS Instrument (OPROSI) allows fast-response quantification; this is important due to the potentially short-lived nature of particle-bound ROS as well as fast-changing atmospheric conditions, especially in urban environments. The instrument design allows for automated operation and extended field operation with twice-daily presence of an operator. As well as having sensitivity suitable for ambient level measurement, the instrument is also suitable at concentrations such as those required for laboratory and chamber toxicological studies.

  13. Calibration of Herschel SPIRE FTS observations at different spectral resolutions

    NASA Astrophysics Data System (ADS)

    Marchili, N.; Hopwood, R.; Fulton, T.; Polehampton, E. T.; Valtchanov, I.; Zaretski, J.; Naylor, D. A.; Griffin, M. J.; Imhof, P.; Lim, T.; Lu, N.; Makiwa, G.; Pearson, C.; Spencer, L.

    2017-01-01

    The SPIRE Fourier Transform Spectrometer on-board the Herschel Space Observatory had two standard spectral resolution modes for science observations: high resolution (HR) and low resolution (LR), which could also be performed in sequence (H+LR). A comparison of the HR and LR resolution spectra taken in this sequential mode revealed a systematic discrepancy in the continuum level. Analysing the data at different stages during standard pipeline processing demonstrates that the telescope and instrument emission affect HR and H+LR observations in a systematically different way. The origin of this difference is found to lie in the variation of both the telescope and instrument response functions, while it is triggered by fast variation of the instrument temperatures. As it is not possible to trace the evolution of the response functions using housekeeping data from the instrument subsystems, the calibration cannot be corrected analytically. Therefore, an empirical correction for LR spectra has been developed, which removes the systematic noise introduced by the variation of the response functions.

  14. Fast simulation tool for ultraviolet radiation at the earth's surface

    NASA Astrophysics Data System (ADS)

    Engelsen, Ola; Kylling, Arve

    2005-04-01

    FastRT is a fast, yet accurate, UV simulation tool that computes downward surface UV doses, UV indices, and irradiances in the spectral range 290 to 400 nm with a resolution as small as 0.05 nm. It computes a full UV spectrum within a few milliseconds on a standard PC, and enables the user to convolve the spectrum with user-defined and built-in spectral response functions including the International Commission on Illumination (CIE) erythemal response function used for UV index calculations. The program accounts for the main radiative input parameters, i.e., instrumental characteristics, solar zenith angle, ozone column, aerosol loading, clouds, surface albedo, and surface altitude. FastRT is based on look-up tables of carefully selected entries of atmospheric transmittances and spherical albedos, and exploits the smoothness of these quantities with respect to atmospheric, surface, geometrical, and spectral parameters. An interactive site, http://nadir.nilu.no/~olaeng/fastrt/fastrt.html, enables the public to run the FastRT program with most input options. This page also contains updated information about FastRT and links to freely downloadable source codes and binaries.

  15. Compact rotating cup anemometer

    NASA Technical Reports Server (NTRS)

    Wellman, J. B.

    1968-01-01

    Compact, collapsible rotating cup anemometer is used in remote locations where portability and durability are factors in the choice of equipment. This lightweight instrument has a low wind-velocity threshold, is capable of withstanding large mechanical shocks while in its stowed configuration, and has fast response to wind fluctuations.

  16. Level monitoring system with pulsating sensor—Application to online level monitoring of dashpots in a fast breeder reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Malathi, N.; Sahoo, P., E-mail: sahoop@igcar.gov.in; Ananthanarayanan, R.

    2015-02-15

    An innovative continuous type liquid level monitoring system constructed by using a new class of sensor, viz., pulsating sensor, is presented. This device is of industrial grade and it is exclusively used for level monitoring of any non conducting liquid. This instrument of unique design is suitable for high resolution online monitoring of oil level in dashpots of a sodium-cooled fast breeder reactor. The sensing probe is of capacitance type robust probe consisting of a number of rectangular mirror polished stainless steel (SS-304) plates separated with uniform gaps. The performance of this novel instrument has been thoroughly investigated. The precision,more » sensitivity, response time, and the lowest detection limit in measurement using this device are <0.01 mm, ∼100 Hz/mm, ∼1 s, and ∼0.03 mm, respectively. The influence of temperature on liquid level is studied and the temperature compensation is provided in the instrument. The instrument qualified all recommended tests, such as environmental, electromagnetic interference and electromagnetic compatibility, and seismic tests prior to its deployment in nuclear reactor. With the evolution of this level measurement approach, it is possible to provide dashpot oil level sensors in fast breeder reactor for the first time for continuous measurement of oil level in dashpots of Control and Safety Rod Drive Mechanism during reactor operation.« less

  17. Förster resonance energy transfer (FRET)-based picosecond lifetime reference for instrument response evaluation

    NASA Astrophysics Data System (ADS)

    Luchowski, R.; Kapusta, P.; Szabelski, M.; Sarkar, P.; Borejdo, J.; Gryczynski, Z.; Gryczynski, I.

    2009-09-01

    Förster resonance energy transfer (FRET) can be utilized to achieve ultrashort fluorescence responses in time-domain fluorometry. In a poly(vinyl) alcohol matrix, the presence of 60 mM Rhodamine 800 acceptor shortens the fluorescence lifetime of a pyridine 1 donor to about 20 ps. Such a fast fluorescence response is very similar to the instrument response function (IRF) obtained using scattered excitation light. A solid fluorescent sample (e.g a film) with picosecond lifetime is ideal for IRF measurements and particularly useful for time-resolved microscopy. Avalanche photodiode detectors, commonly used in this field, feature color- dependent-timing responses. We demonstrate that recording the fluorescence decay of the proposed FRET-based reference sample yields a better IRF approximation than the conventional light-scattering method and therefore avoids systematic errors in decay curve analysis.

  18. Impact of Aircraft Emissions on Air Quality in the Vicinity of Airports. Volume 4. Nitrogen Dioxide and Hydrocarbons.

    DTIC Science & Technology

    1984-04-01

    PROCESSING 2.1.1 Siting, Instrumentation, and Measurement History The ANLIEES Air Resources Section Air Monitoring Laboratory (AM4L) was located at... supplied from an external cylinder in a blend containing 10% C2H4 reactant and 90% CO2 diluent. The instrument was operated in a fast-response mode...an alternative procedure was adopted for their determination and was utilized to determine time lags for several different periods of time scattered

  19. A compact, fast UV photometer for measurement of ozone from research aircraft

    NASA Astrophysics Data System (ADS)

    Gao, R. S.; Ballard, J.; Watts, L. A.; Thornberry, T. D.; Ciciora, S. J.; McLaughlin, R. J.; Fahey, D. W.

    2012-09-01

    In situ measurements of atmospheric ozone (O3) are performed routinely from many research aircraft platforms. The most common technique depends on the strong absorption of ultraviolet (UV) light by ozone. As atmospheric science advances to the widespread use of unmanned aircraft systems (UASs), there is an increasing requirement for minimizing instrument space, weight, and power while maintaining instrument accuracy, precision and time response. The design and use of a new, dual-beam, UV photometer instrument for in situ O3 measurements is described. A polarization optical-isolator configuration is utilized to fold the UV beam inside the absorption cells, yielding a 60-cm absorption length with a 30-cm cell. The instrument has a fast sampling rate (2 Hz at <200 hPa, 1 Hz at 200-500 hPa, and 0.5 Hz at ≥ 500 hPa), high accuracy (3% excluding operation in the 300-450 hPa range, where the accuracy may be degraded to about 5%), and excellent precision (1.1 × 1010 O3 molecules cm-3 at 2 Hz, which corresponds to 3.0 ppb at 200 K and 100 hPa, or 0.41 ppb at 273 K and 1013 hPa). The size (36 l), weight (18 kg), and power (50-200 W) make the instrument suitable for many UASs and other airborne platforms. Inlet and exhaust configurations are also described for ambient sampling in the troposphere and lower stratosphere (1000-50 hPa) that control the sample flow rate to maximize time response while minimizing loss of precision due to induced turbulence in the sample cell. In-flight and laboratory intercomparisons with existing O3 instruments show that measurement accuracy is maintained in flight.

  20. BMSW - Fast Solar Wind Monitor - three years in orbit: Status and prospects

    NASA Astrophysics Data System (ADS)

    Prech, Lubomir; Zastenker, Georgy; Nemecek, Zdenek; Safrankova, Jana; Vaverka, Jakub; Cermak, Ivo; Chesalin, Lev S.; Gavrilova, Elena

    Fast Solar Wind Monitor BMSW is an instrument flown as a part of the PLASMA-F complex onboard the Russian Spektr-R radioastronomical spacecraft. The spacecraft was launched on July 18, 2011. During the COSPAR-2014 Assembly meeting, the instrument is supposed to celebrate three successful years in operation. With a set of 6 Faraday’s cups, the instrument has a unique time resolution --- 0.5--1 s for a full energy spectrum (96 energy steps) and 31~ms for basic solar wind plasma parameters directing the instrument to study of fast solar wind discontinuities including interplanetary shocks, a fast variability of proton and alpha particle parameters, and to study of solar wind turbulence up to the ion kinetic scales. The measurement technique, its implementation, and ground data processing are discussed in the contribution. The performance of the instrument design and electronics are presented. We discuss heritage of this instrument utilized in design of future instruments being prepared for the further projects as Luna-Glob.

  1. Trends in Vocational Education in the Arts 1980. Fast Response Survey System.

    ERIC Educational Resources Information Center

    Wright, Douglas A.; Farris, Elizabeth

    A study examined the nature and extent of vocational arts education programs throughout the 50 states. During the study, data were sought concerning those programs designed to prepare students for occupations in 14 arts areas: dance; vocal music; instrumental music; theater; radio, television, and video; cinematography; photography; graphic arts;…

  2. Fast ion mass spectrometry and charged particle spectrography investigations of transverse ion acceleration and beam-plasma interactions

    NASA Technical Reports Server (NTRS)

    Gibson, W. C.; Tomlinson, W. M.; Marshall, J. A.

    1987-01-01

    Ion acceleration transverse to the magnetic field in the topside ionosphere was investigated. Transverse acceleration is believed to be responsible for the upward-moving conical ion distributions commonly observed along auroral field lines at altitudes from several hundred to several thousand kilometers. Of primary concern in this investigation is the extent of these conic events in space and time. Theoretical predictions indicate very rapid initial heating rates, depending on the ion species. These same theories predict that the events will occur within a narrow vertical region of only a few hundred kilometers. Thus an instrument with very high spatial and temporal resolution was required; further, since different heating rates were predicted for different ions, it was necessary to obtain composition as well as velocity space distributions. The fast ion mass spectrometer (FIMS) was designed to meet these criteria. This instrument and its operation is discussed.

  3. FROM THE HISTORY OF PHYSICS: Georgii L'vovich Shnirman: designer of fast-response instruments

    NASA Astrophysics Data System (ADS)

    Bashilov, I. P.

    1994-07-01

    A biography is given of the outstanding Russian scientist Georgii L'vovich Shnirman, whose scientific life had been 'top secret'. He was an experimental physicist and instrument designer, the founder of many branches of the Soviet instrument-making industry, the originator of a theory of electric methods of integration and differentiation, a theory of astasisation of pendulums, and also of original measurement methods. He was the originator and designer of automatic systems for the control of the measuring apparatus used at nuclear test sites and of automatic seismic station systems employed in monitoring nuclear tests. He also designed the first loop oscilloscopes in the Soviet Union, high-speed photographic and cine cameras (streak cameras, etc.), and many other unique instruments, including some mounted on moving objects.

  4. Very Fast Temperature Measurement with a Thin Lamp Filament

    ERIC Educational Resources Information Center

    G. Calza, Gratton, L. M.; Lopez-Arias, T.; Oss, S.

    2012-01-01

    We construct a thermometer exploiting the electric resistance of the filament of a small lamp used in micro-illumination settings. The instrument may guarantee a response time better than 10 ms, i.e. much faster than commercial thermocouples or other quite expensive devices. This makes our thermometer a useful one in several processes which are…

  5. Flight instrument and telemetry response and its inversion

    NASA Technical Reports Server (NTRS)

    Weinberger, M. R.

    1971-01-01

    Mathematical models of rate gyros, servo accelerometers, pressure transducers, and telemetry systems were derived and their parameters were obtained from laboratory tests. Analog computer simulations were used extensively for verification of the validity for fast and large input signals. An optimal inversion method was derived to reconstruct input signals from noisy output signals and a computer program was prepared.

  6. Estimating Surface NO2 and SO2 Mixing Ratios from Fast-Response Total Column Observations and Potential Application to Geostationary Missions

    EPA Science Inventory

    Total-column nitrogen dioxide (NO2) data collected by a ground-based sun-tracking spectrometer system 21 (Pandora) and an photolytic-converter-based in-situ instrument collocated at NASA’s Langley Research Center in 22 Hampton, Virginia were analyzed to study the relationship bet...

  7. Particle size distributions from laboratory-scale biomass fires using fast response instruments

    Treesearch

    S Hosseini; L. Qi; D. Cocker; D. Weise; A. Miller; M. Shrivastava; J.W. Miller; S. Mahalingam; M. Princevac; H. Jung

    2010-01-01

    Particle size distribution from biomass combustion is an important parameter as it affects air quality, climate modelling and health effects. To date, particle size distributions reported from prior studies vary not only due to difference in fuels but also difference in experimental conditions. This study aims to report characteristics of particle size distributions in...

  8. Response to "Rating Teachers Cheaper, Faster, and Better: Not so Fast": It's About Evidence

    ERIC Educational Resources Information Center

    Gargani, John; Strong, Michael

    2015-01-01

    In Gargani and Strong (2014), we describe The Rapid Assessment of Teacher Effectiveness (RATE), a new teacher evaluation instrument. Our account of the validation research associated with RATE inspired a review by Good and Lavigne (2015). Here, we reply to the main points of their review. We elaborate on the validity, reliability, theoretical…

  9. TRIPPING CIRCUIT

    DOEpatents

    Lees, G.W.; McCormick, E.D.

    1962-05-22

    A tripping circuit employing a magnetic amplifier for tripping a reactor in response to power level, period, or instrument failure is described. A reference winding and signal winding are wound in opposite directions on the core. Current from an ion chamber passes through both windings. If the current increases at too fast a rate, a shunt circuit bypasses one or the windings and the amplifier output reverses polarity. (AEC)

  10. Fast, Large-Area, Wide-Bandgap UV Photodetector for Cherenkov Light Detection

    NASA Technical Reports Server (NTRS)

    Wrbanek, John D.; Wrbanek, Susan Y.

    2013-01-01

    Due to limited resources available for power and space for payloads, miniaturizing and integrating instrumentation is a high priority for addressing the challenges of manned and unmanned deep space missions to high Earth orbit (HEO), near Earth objects (NEOs), Lunar and Martian orbits and surfaces, and outer planetary systems, as well as improvements to high-altitude aircraft safety. New, robust, and compact detectors allow future instrumentation packages more options in satisfying specific mission goals. A solid-state ultraviolet (UV) detector was developed with a theoretical fast response time and large detection area intended for application to Cherenkov detectors. The detector is based on the wide-bandgap semiconductor zinc oxide (ZnO), which in a bridge circuit can detect small, fast pulses of UV light like those required for Cherenkov detectors. The goal is to replace the role of photomultiplier tubes in Cherenkov detectors with these solid-state devices, saving on size, weight, and required power. For improving detection geometry, a spherical detector to measure high atomic number and energy (HZE) ions from any direction has been patented as part of a larger space radiation detector system. The detector will require the development of solid-state UV photodetectors fast enough (2 ns response time or better) to detect the shockwave of Cherenkov light emitted as the ions pass through a quartz, sapphire, or acrylic ball. The detector must be small enough to fit in the detector system structure, but have an active area large enough to capture enough Cherenkov light from the sphere. The detector is fabricated on bulk single-crystal undoped ZnO. Inter - digitated finger electrodes and contact pads are patterned via photolithography, and formed by sputtered metal of silver, platinum, or other high-conductivity metal.

  11. Characterization of a turbomolecular-pumped magnetic sector mass spectrometer

    NASA Technical Reports Server (NTRS)

    Mehta, Narinder K.

    1988-01-01

    A Perkin Elmer MGA-1200, turbomolecular-pumped, magnetic sector, multiple gas analyzer mass spectrometer with modified inlet for fast response was characterized for the analysis of hydrogen, helium, oxygen and argon in nitrogen and helium background gases. This instrument was specially modified for the Vanderberg AFB SLC-6 Hydrogen Disposal Test Program, as a part of the Hydrogen Sampling System (H2S2). Linearity, precision, drift, detection limits and accuracy among other analytical parameters for each of the background gas were studied to evaluate the performance of the instrument. The result demonstrates that H2S2 mass spectrometer is a stable instrument and can be utilized for the quantitative analytical determination of hydrogen, helium, oxygen and argon in nitrogen and helium background gases.

  12. Studying Fast Reactions: Construction and Use of a Low-Cost Continuous-Flow Instrument

    ERIC Educational Resources Information Center

    Bisson, Patrick J.; Whitten, James E.

    2006-01-01

    The construction and use of a low-cost continuous-flow instrument for measuring the kinetics of fast reaction which include the use of an light emitting diode light source, a photodiode-on-a-chip detector, and a position sensor is demonstrated. The instrument is suitable for the physical chemistry laboratory and could be used to study the kinetics…

  13. The effect of fast-food restaurants on childhood obesity: a school level analysis.

    PubMed

    Alviola, Pedro A; Nayga, Rodolfo M; Thomsen, Michael R; Danforth, Diana; Smartt, James

    2014-01-01

    We analyze, using an instrumental variable approach, the effect of the number of fast-food restaurants on school level obesity rates in Arkansas. Using distance to the nearest major highway as an instrument, our results suggest that exposure to fast-food restaurants can impact weight outcomes. Specifically, we find that the number of fast-food restaurants within a mile from the school can significantly affect school level obesity rates. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Cardiovascular and metabolic responses to fasting and thermoneutrality are conserved in obese Zucker rats.

    PubMed

    Overton, J M; Williams, T D; Chambers, J B; Rashotte, M E

    2001-04-01

    The primary purpose of the study was to test the hypothesis that reduced leptin signaling is necessary to elicit the cardiovascular and metabolic responses to fasting. Lean (Fa/?; normal leptin receptor; n = 7) and obese (fa/fa; mutated leptin receptor; n = 8) Zucker rats were instrumented with telemetry transmitters and housed in metabolic chambers at 23 degrees C (12:12-h light-dark cycle) for continuous (24 h) measurement of metabolic and cardiovascular variables. Before fasting, mean arterial pressure (MAP) was higher (MAP: obese = 103 +/- 3; lean = 94 +/- 1 mmHg), whereas oxygen consumption (VO(2): obese = 16.5 +/- 0.3; lean = 18.6 +/- 0.2 ml. min(-1). kg(-0.75)) was lower in obese Zucker rats compared with their lean controls. Two days of fasting had no effect on MAP in either lean or obese Zucker rats, whereas VO(2) (obese = -3.1 +/- 0.3; lean = -2.9 +/- 0.1 ml. min(-1). kg(-0.75)) and heart rate (HR: obese = -56 +/- 4; lean = -42 +/- 4 beats/min) were decreased markedly in both groups. Fasting increased HR variability both in lean (+1.8 +/- 0.4 ms) and obese (+2.6 +/- 0.3 ms) Zucker rats. After a 6-day period of ad libitum refeeding, when all parameters had returned to near baseline levels, the cardiovascular and metabolic responses to 2 days of thermoneutrality (ambient temperature 29 degrees C) were determined. Thermoneutrality reduced VO(2) (obese = -2.4 +/- 0.2; lean = -3.3 +/- 0.2 ml. min(-1). kg(-0.75)), HR (obese = -46 +/- 5; lean = -55 +/- 4 beats/min), and MAP (obese = -13 +/- 6; lean = -10 +/- 1 mmHg) similarly in lean and obese Zucker rats. The results indicate that the cardiovascular and metabolic responses to fasting and thermoneutrality are conserved in Zucker rats and suggest that intact leptin signaling may not be requisite for the metabolic and cardiovascular responses to reduced energy intake.

  15. Evaluation of a fast single-photon avalanche photodiode for measurement of early transmitted photons through diffusive media.

    PubMed

    Mu, Ying; Valim, Niksa; Niedre, Mark

    2013-06-15

    We tested the performance of a fast single-photon avalanche photodiode (SPAD) in measurement of early transmitted photons through diffusive media. In combination with a femtosecond titanium:sapphire laser, the overall instrument temporal response time was 59 ps. Using two experimental models, we showed that the SPAD allowed measurement of photon-density sensitivity functions that were approximately 65% narrower than the ungated continuous wave case at very early times. This exceeds the performance that we have previously achieved with photomultiplier-tube-based systems and approaches the theoretical maximum predicted by time-resolved Monte Carlo simulations.

  16. Calibrations and Comparisons of Aerosol Spectrometers linking Ground and Airborne Measurements

    NASA Astrophysics Data System (ADS)

    Williamson, C.; Brock, C. A.; Erdesz, F.

    2015-12-01

    The nucleation-mode aerosol size spectrometer (NMASS), a fast-time response instrument measuring aerosol size distributions between 5 and 60nm, is to sample in the boundary layer and free troposphere on NASA's Atmospheric Tomography mission (ATom), providing contiguous data with global coverage in all four seasons. In preparation for this the NMASS is calibrated for the expected flight conditions and compatibility studies are made with ground-based instrumentation. The NMASS is comprised of 5 parallel condensation particle counters (CPCs) using perfluoro-tributylamine as a working fluid. Understanding the variation of CPC counting efficiencies with respect to the chemical composition of the sample is important for accurate data analysis and can be used to give indirect information about sample chemical composition. This variation is strongly dependent on the working fluid. The absolute responses and associated variations of the NMASS to ammonium sulfate and limonene ozonolysis products, compounds pertinent to the composition of particles nucleated in the free troposphere and boundary later, are compared to those of butanol, diethylene-glycol and water based CPCs, which are more commonly used in ground-based measurements. While fast time-response is key to measuring aerosol size distributions on flights, high size-resolution is often prioritized for ground-based measurements, and so a scanning mobility particle sizer (SMPS) is commonly used. Inter-comparison between NMASS and SMPS data is non-trivial because of the different working principles and resolutions of the instruments and yet it is vital, for example, for understanding the sources of particles observed during flights and the global relevance of phenomena observed from field stations and in chambers. We report compatibility studies on inversions of data from the SMPS and NMASS, evaluating temporal and spatial resolution and sources of uncertainty.

  17. Mars Acoustic Anemometer

    NASA Astrophysics Data System (ADS)

    Banfield, D. J.

    2012-12-01

    We have developed a very high performance anemometer (wind gauge) for use at Mars. This instrument has great scientific as well as strategic reasons to be included on all future missions to the surface of Mars. We will discuss why we set out to develop this instrument, as well as why the previous wind sensors for Mars are insufficient to meet the scientific and strategic needs at Mars. We will also discuss how the instrument works, and how it differs from terrestrial counterparts. Additionally, we will discuss the current status of the instrument. Measuring winds at Mars is important to better understand the atmospheric circulation at Mars, as well as exchange between the surface and atmosphere. The main conduit of transport of water, and hence its current stability at any particular location on Mars is controlled by these atmospheric motions and the exchange between surface and atmosphere. Mars' large-scale winds are moderately well understood from orbital observations, but the interaction with the surface can only be addressed adequately in situ. Previous anemometers have been 2-D (with the exception of REMS on MSL) and slow response (typically <1Hz), and relatively low sensitivity/accuracy (>1 m/s). Our instrument is capable of fully 3-D measurements, with fast response (>20 Hz) and great sensitivity/accuracy (~3 cm/s). This significant step forward in performance is important for the surface-atmosphere exchanges of heat, momentum and volatiles. In particular, our instrument could directly measure the heat and momentum fluxes between surface and atmosphere using eddy-flux techniques proven terrestrially. When combined with a fast response volatile analysis instrument (e.g., a TLS) we can also measure eddy fluxes of volatile transport. Such a study would be nearly impossible to carry out with preceding anemometers sent to Mars with insufficient response time and sensitivity to adequately sample the turbulent eddies. Additionally, our instrument, using acoustics is far less susceptible to contaminating influences as other techniques (e.g., hot wire/hot film) that have been used for anemometry at Mars. Our instrument is conceptually derived from the commercial terrestrial sonic anemometers, but uses specialized acoustic transducers to optimally couple with the low density martian air as well as survive the extreme temperature swings on Mars. Additionally, we use sophisticated signal processing to extract as much information as possible in the low S/N environment that is achievable at Mars. We have developed our instrument through to TRL 5, proving it in a martian wind tunnel in Denmark. We found wind speed sensitivities and precision to be of order 3 cm/s, and with appropriate calibration, accuracy can be similar, even when operating at 20-100 Hz. We will also test this instrument at 120,000' altitude (i.e., equivalent to Mars atmospheric density) as an autonomous package on a stratospheric balloon. We are currently developing a TRL 6 version of the instrument that will be tested once again in the Denmark Mars Wind Tunnel. We expect our flight configuration instrument to be about 1 kg, including a 1.5m mast. It will also draw about 2-3W of power. This instrument is now ready to be proposed for future Mars missions, where we believe it will make a significant contribution and a step forward in Mars atmospheric science.

  18. Seasonal CO2 Observations on North and South of Mars as Seen by HEND (Mars Odyssey) and MOLA (MGS)

    NASA Technical Reports Server (NTRS)

    Litvak, M. L.; Mitrofanov, I. G.; Smith, D. E.; Zuber, M. T.; Boynton, W.; Saunders, R. S.; Drake, D.

    2003-01-01

    The first year of neutron mapping measurements from the Mars Odyssey spacecraft are presented based on observations from the High Energy Neutron Detector (HEND). The HEND instrument is a part of GRS suite responsible for registration of epithermal and fast neutrons originating in the Mars subsurface layer. The gamma ray and neutron spectrometers measure the scattering of fast neutrons from the Martian surface, which is caused by bombardment of primary cosmic rays and is strongly sensitive to the presence of hydrogen atoms. Even several percent subsurface hydrogen significantly depresses the flux of epithermal and fast neutrons. The recent Mars Odyssey observations detected a considerable amount of hydrogen, almost certainly corresponding to water ice, in the shallow near surface of the southern and northern hemispheres of Mars.

  19. Modular time division multiplexer: Efficient simultaneous characterization of fast and slow transients in multiple samples

    NASA Astrophysics Data System (ADS)

    Kim, Stephan D.; Luo, Jiajun; Buchholz, D. Bruce; Chang, R. P. H.; Grayson, M.

    2016-09-01

    A modular time division multiplexer (MTDM) device is introduced to enable parallel measurement of multiple samples with both fast and slow decay transients spanning from millisecond to month-long time scales. This is achieved by dedicating a single high-speed measurement instrument for rapid data collection at the start of a transient, and by multiplexing a second low-speed measurement instrument for slow data collection of several samples in parallel for the later transients. The MTDM is a high-level design concept that can in principle measure an arbitrary number of samples, and the low cost implementation here allows up to 16 samples to be measured in parallel over several months, reducing the total ensemble measurement duration and equipment usage by as much as an order of magnitude without sacrificing fidelity. The MTDM was successfully demonstrated by simultaneously measuring the photoconductivity of three amorphous indium-gallium-zinc-oxide thin films with 20 ms data resolution for fast transients and an uninterrupted parallel run time of over 20 days. The MTDM has potential applications in many areas of research that manifest response times spanning many orders of magnitude, such as photovoltaics, rechargeable batteries, amorphous semiconductors such as silicon and amorphous indium-gallium-zinc-oxide.

  20. Modular time division multiplexer: Efficient simultaneous characterization of fast and slow transients in multiple samples.

    PubMed

    Kim, Stephan D; Luo, Jiajun; Buchholz, D Bruce; Chang, R P H; Grayson, M

    2016-09-01

    A modular time division multiplexer (MTDM) device is introduced to enable parallel measurement of multiple samples with both fast and slow decay transients spanning from millisecond to month-long time scales. This is achieved by dedicating a single high-speed measurement instrument for rapid data collection at the start of a transient, and by multiplexing a second low-speed measurement instrument for slow data collection of several samples in parallel for the later transients. The MTDM is a high-level design concept that can in principle measure an arbitrary number of samples, and the low cost implementation here allows up to 16 samples to be measured in parallel over several months, reducing the total ensemble measurement duration and equipment usage by as much as an order of magnitude without sacrificing fidelity. The MTDM was successfully demonstrated by simultaneously measuring the photoconductivity of three amorphous indium-gallium-zinc-oxide thin films with 20 ms data resolution for fast transients and an uninterrupted parallel run time of over 20 days. The MTDM has potential applications in many areas of research that manifest response times spanning many orders of magnitude, such as photovoltaics, rechargeable batteries, amorphous semiconductors such as silicon and amorphous indium-gallium-zinc-oxide.

  1. On the calibration and use of Dual Electron Sensors for NASA's Magnetospheric MultiScale mission

    NASA Astrophysics Data System (ADS)

    Avanov, L. A.; Gliese, U.; Pollock, C. J.; Barrie, A.; Mariano, A. J.; Tucker, C. J.; Jacques, A. D.; Zeuch, M.; Shields, N.; Christian, K. D.

    2013-12-01

    The scientific target of NASA's Magnetospheric MultiScale (MMS) mission is to study the fundamentally important phenomenon of magnetic reconnection. Theoretical models of this process predict a small (order of ten kilometers) size for the diffusion region where electrons are demagnetized at the dayside magnetopause. Yet, the region may typically sweep over the spacecraft at relatively high speeds of 50km/s. That is why Fast Plasma Investigation (FPI) instrument suite must have extremely high time resolution for measurements of the 3D particle distribution functions. The Dual Electron Spectrometers (DESs) provide fast (30ms) 3D electron velocity distributions, from 10eV to 30,000 eV, as part of the Fast Plasma Investigation (FPI) on NASA's Magnetospheric MultiScale (MMS) mission. This is accomplished by combining the measurements from eight different spectrometers (packaged in four dual sets) on each MMS spacecraft to produce each full distribution. This approach presents a new and challenging aspect to the calibration and operation of these instruments. The response uniformity among the spectrometer set, the consistency and reliability of their calibration in both sensitivity and their phase space selectivity (energy and angle), and the approach to handling any temporal evolution of these calibrated characteristics all assume enhanced importance in this application. In this paper, we will present brief descriptions of the spectrometers and our approach their ground calibration, trended results of those calibrations, and our plans to detect, track, and respond to any temporal evolution in instrument performance through the life of the mission.

  2. 4-D Model of CO2 Deposition at North and South of Mars from HEND/Odyssey and MOLA/MGS

    NASA Technical Reports Server (NTRS)

    Litvak, M. L.; Mitrofanov, I. G.; Kozyrev, A. S.; Sanin, A. B.; Tretyakov, V.; Smith, D. E.; Zuber, M. T.; Boynton, W. V.; Hamara, D. K.; Shinohara, C.

    2003-01-01

    The first 1.5 year of neutron mapping measurements onboard Mars Odyssey spacecraft are presented based on High Energy Neutron Detector (HEND) observations. HEND instrument is a part of GRS suite responsible for registration of epithermal and fast neutrons originating in Mars subsurface layer. The scattering of fast neutrons in Mars surface caused by primary cosmic rays is strongly sensitive to presence of hydrogen atoms. Even several percents of subsurface water significantly depress epithermal and fast neutron flux. It turns orbit neutron spectroscopy into one of most efficient methods for finding distribution of subsurface water. The Mars Odyssey observations revealed huge water- ice regions above 60N and 60S latitudes. It was founded that distribution of subsurface water has layered structure at these regions. It is thought that more than 50% wt water ice covered by relatively dry layer with different thickness.

  3. Fast Response Shape Memory Effect Titanium Nickel (TiNi) Foam Torque Tubes

    NASA Technical Reports Server (NTRS)

    Jardine, Peter

    2014-01-01

    Shape Change Technologies has developed a process to manufacture net-shaped TiNi foam torque tubes that demonstrate the shape memory effect. The torque tubes dramatically reduce response time by a factor of 10. This Phase II project matured the actuator technology by rigorously characterizing the process to optimize the quality of the TiNi and developing a set of metrics to provide ISO 9002 quality assurance. A laboratory virtual instrument engineering workbench (LabVIEW'TM')-based, real-time control of the torsional actuators was developed. These actuators were developed with The Boeing Company for aerospace applications.

  4. The Parameterization of Top-Hat Particle Sensors with Microchannel-Plate-Based Detection Systems and its Application to the Fast Plasma Investigation on NASA's Magnetospheric MultiScale Mission

    NASA Technical Reports Server (NTRS)

    Gershman, Daniel J.; Gliese, Ulrik; Dorelli, John C.; Avanov, Levon A.; Barrie, Alexander C.; Chornay, Dennis J.; MacDonald, Elizabeth A.; Holland, Matthew P.; Pollock, Craig J.

    2015-01-01

    The most common instrument for low energy plasmas consists of a top-hat electrostatic analyzer geometry coupled with a microchannel-plate (MCP)-based detection system. While the electrostatic optics for such sensors are readily simulated and parameterized during the laboratory calibration process, the detection system is often less well characterized. Furthermore, due to finite resources, for large sensor suites such as the Fast Plasma Investigation (FPI) on NASA's Magnetospheric Multiscale (MMS) mission, calibration data are increasingly sparse. Measurements must be interpolated and extrapolated to understand instrument behavior for untestable operating modes and yet sensor inter-calibration is critical to mission success. To characterize instruments from a minimal set of parameters we have developed the first comprehensive mathematical description of both sensor electrostatic optics and particle detection systems. We include effects of MCP efficiency, gain, scattering, capacitive crosstalk, and charge cloud spreading at the detector output. Our parameterization enables the interpolation and extrapolation of instrument response to all relevant particle energies, detector high voltage settings, and polar angles from a small set of calibration data. We apply this model to the 32 sensor heads in the Dual Electron Sensor (DES) and 32 sensor heads in the Dual Ion Sensor (DIS) instruments on the 4 MMS observatories and use least squares fitting of calibration data to extract all key instrument parameters. Parameters that will evolve in flight, namely MCP gain, will be determined daily through application of this model to specifically tailored in-flight calibration activities, providing a robust characterization of sensor suite performance throughout mission lifetime. Beyond FPI, our model provides a valuable framework for the simulation and evaluation of future detection system designs and can be used to maximize instrument understanding with minimal calibration resources.

  5. A High-Precision, Fast-Response Airborne CO2 Analyzer for In Situ Sampling From the Surface to the Middle Stratosphere

    NASA Technical Reports Server (NTRS)

    Daube, B. C., Jr.; Boering, K. A.; Andrews, Arlyn E.; Wofsy, S. C.

    2001-01-01

    Two in situ CO2 analyzers have been developed for deployment on the NASA ER-2 aircraft and on stratospheric balloons. The ER-2 instrument has had more than 150 flights during 21 deployments from 1992 to 2000, resulting in a dataset with nearly pole-to-pole coverage that includes data from all seasons in both hemispheres except austral summer. In-flight calibrations show that the typical long-term (i.e. flight-to-flight) precision of the instruments is better than plus or minus 0.1 ppmv. The flight standards are traceable to standards held by the Scripps Institute of Oceanography and the National Oceanic and Atmospheric Administration's Climate Monitoring and Diagnostics Laboratory. The balloon instrument has had 8 balloon flights since September 1996, providing the first in situ observations of CO2 above approx. 21 km. In addition, the balloon instrument has been flown onboard a Cessna Citation II aircraft for sampling between the surface and 10 km. In this paper, the instrumentation and calibration procedures for both instruments are described in detail. An intercomparison of the two instruments during the Photochemistry of Ozone Loss in the Arctic Region In Summer (POLARIS) project showed that, on average, the instruments agreed to within 0.05 ppmv.

  6. A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils.

    PubMed

    Rêgo Segundo, Alan Kardek; Martins, José Helvecio; Monteiro, Paulo Marcos de Barros; de Oliveira, Rubens Alves; Freitas, Gustavo Medeiros

    2015-10-05

    The scarcity of drinking water affects various regions of the planet. Although climate change is responsible for the water availability, humanity plays an important role in preserving this precious natural resource. In case of negligence, the likely trend is to increase the demand and the depletion of water resources due to the increasing world population. This paper addresses the development, design and construction of a low cost system for measuring soil volumetric water content (θ), electrical conductivity (σ) and temperature (T), in order to optimize the use of water, energy and fertilizer in food production. Different from the existing measurement instruments commonly deployed in these applications, the proposed system uses an auto-balancing bridge circuit as measurement method. The proposed models to estimate θ and σ and correct them in function of T are compared to the ones reported in literature. The final prototype corresponds to a simple circuit connected to a pair of electrode probes, and presents high accuracy, high signal to noise ratio, fast response, and immunity to stray capacitance. The instrument calibration is based on salt solutions with known dielectric constant and electrical conductivity as reference. Experiments measuring clay and sandy soils demonstrate the satisfactory performance of the instrument.

  7. Development of compact particle detectors for space based instruments

    NASA Astrophysics Data System (ADS)

    Barner, Lindsey; Grove, Andrew; Mohler, Jacob; Sisson, Caleb; Roth, Alex; Kryemadhi, Abaz

    2017-01-01

    The Silicon Photomultipliers (SiPMs) are new photon-detectors which have been increasingly used in particle physics. Their small size, good single photon resolution, simple readout, and immunity to magnetic fields offers benefits compared to traditional photomultipliers. LYSO and CeBr3 crystals are relatively new scintillators with high stopping power, very good light yield and fast decay time. The response of these detectors to low energy gamma rays will be presented. NASA Pennsylvania Space Grant Consortium.

  8. Atmospheric methane measurement instrument using a Zeeman-split He-Ne laser

    NASA Technical Reports Server (NTRS)

    Mcmanus, J. Barry; Kebabian, Paul L.; Kolb, Charles E.

    1989-01-01

    The construction of an atmospheric methane measurement instrument based on a Zeeman-split IR He-Ne laser is reported. The laser has a tranverse magnetic field over about 2/3 of its gain length and can oscillate at an (unsplit) frequency (2947.91/cm) centered on a methane absorption line, or on either of two frequencies split by + or - 0.055/cm from the center, with low CH4 absorption. The laser is tuned to dwell sequentially at each frequency, giving two differential absorption measurements in each 46-ms tuning cycle. Atmospheric measurements are made using two multiple pass absorption cells, one with fast (0.75-s) and one with slow (5-s) flow response times. Fluctuations in ambient CH4 of about 20-ppb (rms, 1-s averaging) are detected, with interference fringe effects the dominant noise source. The instrument has operated in a field experiment (NASA GTE/ABLE-3A) in Alaska.

  9. Expanding the role of striatal cholinergic interneurons and the midbrain dopamine system in appetitive instrumental conditioning.

    PubMed

    Crossley, Matthew J; Horvitz, Jon C; Balsam, Peter D; Ashby, F Gregory

    2016-01-01

    The basal ganglia are a collection of subcortical nuclei thought to underlie a wide variety of vertebrate behavior. Although a great deal is known about the functional and physiological properties of the basal ganglia, relatively few models have been formally developed that have been tested against both behavioral and physiological data. Our previous work (Ashby FG, Crossley MJ. J Cogn Neurosci 23: 1549-1566, 2011) showed that a model grounded in the neurobiology of the basal ganglia could account for basic single-neuron recording data, as well as behavioral phenomena such as fast reacquisition that constrain models of conditioning. In this article we show that this same model accounts for a variety of appetitive instrumental conditioning phenomena, including the partial reinforcement extinction (PRE) effect, rapid and slowed reacquisition following extinction, and renewal of previously extinguished instrumental responses by environmental context cues. Copyright © 2016 the American Physiological Society.

  10. Dual Ion Spectrometers and Their Calibration for the Fast Plasma Investigation on NASA's Magnetospheric Multiscale Mission

    NASA Technical Reports Server (NTRS)

    Coffey, V. N.; Chandler, M. O.

    2017-01-01

    The scientific target of NASA's Magnetospheric Multiscale (MMS) mission is to study the fundamentally important phenomenon of magnetic reconnection. Theoretical models of this process predict a small size, on the order of hundred kilometers, for the ion diffusion region where ions are demagnetized at the dayside magnetopause. This region may typically sweep over the spacecraft at relatively high speeds of 50 km/s, requiring the fast plasma investigation (FPI) instrument suite to have an extremely high time resolution for measurements of the 3D particle distribution functions. As part of the FPI on MMS, the 16 dual ion spectrometers (DIS) will provide fast (150 ms) 3D ion velocity distributions, from 10 to 30,000 eV/q, by combining the measurements from four dual spectrometers on each of four MMS spacecraft. For any multispacecraft mission, the response uniformity among the spectrometer set assumes an enhanced importance. Due to these demanding instrument requirements and the effort of calibrating more than 32 sensors (16 × 2) within a tight schedule, a highly systematic and precise calibration was required for measurement repeatability. To illustrate how this challenge was met, a brief overview of the FPI DIS was presented with a detailed discussion of the calibration method of approach and implementation. Finally, a discussion of DIS performance results, their unit-to-unit variation, and the lessons learned from this calibration effort are presented.

  11. Research on the Application of Fast-steering Mirror in Stellar Interferometer

    NASA Astrophysics Data System (ADS)

    Mei, R.; Hu, Z. W.; Xu, T.; Sun, C. S.

    2017-07-01

    For a stellar interferometer, the fast-steering mirror (FSM) is widely utilized to correct wavefront tilt caused by atmospheric turbulence and internal instrumental vibration due to its high resolution and fast response frequency. In this study, the non-coplanar error between the FSM and actuator deflection axis introduced by manufacture, assembly, and adjustment is analyzed. Via a numerical method, the additional optical path difference (OPD) caused by above factors is studied, and its effects on tracking accuracy of stellar interferometer are also discussed. On the other hand, the starlight parallelism between the beams of two arms is one of the main factors of the loss of fringe visibility. By analyzing the influence of wavefront tilt caused by the atmospheric turbulence on fringe visibility, a simple and efficient real-time correction scheme of starlight parallelism is proposed based on a single array detector. The feasibility of this scheme is demonstrated by laboratory experiment. The results show that starlight parallelism meets the requirement of stellar interferometer in wavefront tilt preliminarily after the correction of fast-steering mirror.

  12. Integration and Ruggedization of a Commercially Available Gas Chromatograph and Mass Spectrometer (GCMS) for the Resource Prospector Mission (RPM)

    NASA Technical Reports Server (NTRS)

    Loftin, Kathleen; Griffin, Timothy; Captain, Janine

    2013-01-01

    The Resource Prospector is a mission to prospect for lunar volatiles (primarily water) at one of the two lunar poles, as well as demonstrate In-Situ Resource Utilization (ISRU) on the Moon. The Resource Prospector consists of a lander, a rover, and a rover-borne scientific payload. The Regolith and Environment Science and Oxygen & Lunar Volatile Extraction (RESOLVE) payload, will be able to (1) locate near subsurface volatiles, (2) excavate and analyze samples of the volatile-bearing regolith, and (3) demonstrate the form, extractability and usefulness of the materials. The gas chromatograph mass spectrometer (GCMS) is the primary instrument in the RESOLVE instrumentation suite responsible for identification and quantification of the volatiles evolved from the lunar regolith. Specifically, this instrument must have: a low mass, a low power consumption, be able to perform fast analyses of samples ranging from less than one to greater than ninety nine percent water by mass, be autonomously controlled by the payload's software and avionics platform, and be able to operate in the harsh lunar environment. The RPM's short mission duration is the primary driver of the requirement for a very fast analysis time currently base lined at less than 2 minutes per sample. This presentation will discuss the requirements levied upon the GCMS design, lessons learned from a preliminary field demonstration deployment, the current design, and the path forward.

  13. Characterization of a time-resolved non-contact scanning diffuse optical imaging system exploiting fast-gated single-photon avalanche diode detection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Di Sieno, Laura, E-mail: laura.disieno@polimi.it; Dalla Mora, Alberto; Contini, Davide

    2016-03-15

    We present a system for non-contact time-resolved diffuse reflectance imaging, based on small source-detector distance and high dynamic range measurements utilizing a fast-gated single-photon avalanche diode. The system is suitable for imaging of diffusive media without any contact with the sample and with a spatial resolution of about 1 cm at 1 cm depth. In order to objectively assess its performances, we adopted two standardized protocols developed for time-domain brain imagers. The related tests included the recording of the instrument response function of the setup and the responsivity of its detection system. Moreover, by using liquid turbid phantoms with absorbingmore » inclusions, depth-dependent contrast and contrast-to-noise ratio as well as lateral spatial resolution were measured. To illustrate the potentialities of the novel approach, the characteristics of the non-contact system are discussed and compared to those of a fiber-based brain imager.« less

  14. Deployment of a Fast-GCMS System to Measure C2 to C5 Carbonyls, Methanol and Ethanol Aboard Aircraft

    NASA Technical Reports Server (NTRS)

    Apel, Eric C.

    2004-01-01

    Through funding of this proposal, a fast response gas chromatograph/mass spectrometer (FGCMS) instrument to measure less than or equal to C4 carbonyl compounds and methanol was developed for the NASA GTE TRACE-P (Global Tropospheric Experiment, Transport And Chemical Evolution Over The Pacific) mission. The system consists of four major components: sample inlet, preconcentration system, gas chromatograph (GC), and detector. The preconcentration system is a custom-built cryogen-conservative system. The GC is a compact, custom-built unit that can be temperature programmed and rapidly cooled. Detection is accomplished with an Agilent Technologies 5973 mass spectrometer. The FGCMS instrument provides positive identification because the compounds are chromatographically separated and mass selected. During TRACE-P, a sample was analyzed every 5 minutes. The FGCMS limit of detection was between 5 and 75 pptv, depending on the compound. The entire instrument package is contained in a standard NASA instrument rack (106 cm x 61 cm x 135 cm), consumes less than 1200 watts and is fully automated with LabViEW 6i. Methods were developed or producing highly accurate gas phase standards for the target compounds and for testing the system in the presence of potential interferents. This report presents data on these tests and on the general overall performance of the system in the laboratory and aboard the DC-8 aircraft during the mission. Vertical profiles for acetaldehyde, methanol, acetone, propanal, methyl ethyl ketone, and butanal from FGCMS data collected over the entire mission are also presented.

  15. Radar Waveform Pulse Analysis Measurement System for High-Power GaN Amplifiers

    NASA Technical Reports Server (NTRS)

    Thrivikraman, Tushar; Perkovic-Martin, Dragana; Jenabi, Masud; Hoffman, James

    2012-01-01

    This work presents a measurement system to characterize the pulsed response of high-power GaN amplifiers for use in space-based SAR platforms that require very strict amplitude and phase stability. The measurement system is able to record and analyze data on three different time scales: fast, slow, and long, which allows for greater detail of the mechanisms that impact amplitude and phase stability. The system is fully automated through MATLAB, which offers both instrument control capability and in-situ data processing. To validate this system, a high-power GaN HEMT amplifier operated in saturation was characterized. The fast time results show that variations to the amplitude and phase are correlated to DC supply transients, while long time characteristics are correlated to temperature changes.

  16. Fast neutron sensitivity of neutron detectors based on Boron-10 converter layers

    NASA Astrophysics Data System (ADS)

    Mauri, G.; Messi, F.; Kanaki, K.; Hall-Wilton, R.; Karnickis, E.; Khaplanov, A.; Piscitelli, F.

    2018-03-01

    In the last few years many detector technologies for thermal neutron detection have been developed in order to face the shortage of 3He, which is now much less available and more expensive. Moreover the 3He-based detectors can not fulfil the requirements in performance, e.g. the spatial resolution and the counting rate capability needed for the new instruments. The Boron-10-based gaseous detectors have been proposed as a suitable choice. This and other alternative technologies are being developed at ESS. Higher intensities mean higher signals but higher background as well. The signal-to-background ratio is an important feature to study, in particular the γ-ray and the fast neutron contributions. This paper investigates, for the first time, the fast neutrons sensitivity of 10B-based thermal neutron detector. It presents the study of the detector response as a function of energy threshold and the underlying physical mechanisms. The latter are explained with the help of theoretical considerations and simulations.

  17. Unsolved problems in observational astronomy. II. Focus on rapid response - mining the sky with ``thinking" telescopes

    NASA Astrophysics Data System (ADS)

    Vestrand, W. T.; Theiler, J.; Woznia, P. R.

    2004-10-01

    The existence of rapidly slewing robotic telescopes and fast alert distribution via the Internet is revolutionizing our capability to study the physics of fast astrophysical transients. But the salient challenge that optical time domain surveys must conquer is mining the torrent of data to recognize important transients in a scene full of normal variations. Humans simply do not have the attention span, memory, or reaction time required to recognize fast transients and rapidly respond. Autonomous robotic instrumentation with the ability to extract pertinent information from the data stream in real time will therefore be essential for recognizing transients and commanding rapid follow-up observations while the ephemeral behavior is still present. Here we discuss how the development and integration of three technologies: (1) robotic telescope networks; (2) machine learning; and (3) advanced database technology, can enable the construction of smart robotic telescopes, which we loosely call ``thinking'' telescopes, capable of mining the sky in real time.

  18. Multicomponent Breath Analysis With Infrared Absorption Using Room-Temperature Quantum Cascade Lasers

    PubMed Central

    Shorter, Joanne H.; Nelson, David D.; Barry McManus, J.; Zahniser, Mark S.; Milton, Donald K.

    2010-01-01

    Breath analysis is a powerful noninvasive technique for the diagnosis and monitoring of respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD). Nitric oxide (NO) and carbon monoxide (CO) are markers of airway inflammation and can indicate the extent of respiratory diseases. We have developed a compact fast response laser system for analysis of multiple gases by infrared absorption. The instrument uses room temperature quantum cascade lasers to simultaneously measure NO, CO, carbon dioxide (CO2) and nitrous oxide (N2O) in exhaled breath. Four breath flow rates are employed to explore their exchange dynamics in the lungs and airways. We obtain 1-s detection precisions of 0.5-0.8 parts-per-billion (ppb) for NO, CO, and N2O with an instrument response time of less than 1 s. The breath analysis system has been demonstrated in a preliminary study of volunteers. It is currently deployed in a trial clinical study. PMID:20697459

  19. A quick response four decade logarithmic high-voltage stepping supply

    NASA Technical Reports Server (NTRS)

    Doong, H.

    1978-01-01

    An improved high-voltage stepping supply, for space instrumentation is described where low power consumption and fast settling time between steps are required. The high-voltage stepping supply, utilizing an average power of 750 milliwatts, delivers a pair of mirror images with 64 level logarithmic outputs. It covers a four decade range of + or - 2500 to + or - 0.29 volts having an output stability of + or - 0.5 percent or + or - 20 millivolts for all line load and temperature variations. The supply provides a typical step setting time of 1 millisecond with 100 microseconds for the lower two decades. The versatile design features of the high-voltage stepping supply provides a quick response staircase generator as described or a fixed voltage with the option to change levels as required over large dynamic ranges without circuit modifications. The concept can be implemented up to + or - 5000 volts. With these design features, the high-voltage stepping supply should find numerous applications where charged particle detection, electro-optical systems, and high voltage scientific instruments are used.

  20. Nucleus accumbens core dopamine signaling tracks the need-based motivational value of food-paired cues

    PubMed Central

    Aitken, Tara J.; Greenfield, Venuz Y.; Wassum, Kate M.

    2016-01-01

    Environmental reward-predictive stimuli provide a major source of motivation for instrumental reward-seeking activity and this has been linked to dopamine signaling in the nucleus accumbens (NAc). This cue-induced incentive motivation can be quite general, not restricted to instrumental actions that earn the same unique reward, and is also typically regulated by one’s current need state, such that cues only motivate actions when this is adaptive. But it is unknown whether cue-evoked dopamine signaling is similarly regulated by need state. Here we used fast-scan cyclic voltammetry to monitor dopamine concentration changes in the NAc core of rats during a Pavlovian-to-instrumental transfer (PIT) task in which the motivating influence of two cues, each signaling a distinct food reward (sucrose or food pellets), over an action earning a third unique food reward (grape-flavored polycose) was assessed in a state of hunger and of satiety. Both cues elicited a robust NAc dopamine response when hungry. The magnitude of the sucrose cue-evoked dopamine response correlated with the PIT effect that was selectively induced by this stimulus. Satiety attenuated these cue-evoked dopamine responses and behavioral responding, even though rats had never experienced the specific food rewards in this state. These data demonstrate that cue-evoked NAc core responses are sensitive to current need state, one critical variable that determines the current adaptive utility of cue-motivated behavior. PMID:26715366

  1. Solution for Minimizing Surface Heating Effect for Fast Open-Path CO2 Flux Measurements in Cold Environments

    NASA Astrophysics Data System (ADS)

    Hupp, J. R.; Burba, G. G.; McDermitt, D. K.; Anderson, D. J.; Eckles, R. D.

    2010-12-01

    Open-path design of the high speed gas analyzers is a well-established configuration widely used for measurements of CO2 fluxes and concentrations. This configuration has advantages and deficiencies. Advantages include excellent frequency response, long-term stability, low sensitivity to window contamination, low-power pump-free operation, and infrequent calibration requirements. Deficiencies include susceptibility to precipitation and icing, and a potential need for instrument surface heating correction in extremely cold environments. In spite of the deficiencies, open-path measurements often provide data coverage that would not have been possible using traditional closed-path approach. Data loss from precipitation and icing may not always be prevented for the open-path instruments, while heating effect does not pose a problem for CO2 flux in warm environments. Even in cold environments, the impact of heating on CO2 flux is much smaller than other well-known effects, such as Webb-Pearman-Leuning terms, or frequency response corrections for closed-path analyzers. Nonetheless, instrument surface heating effect in cold environments could be addressed scientifically, via developing the theoretical corrections, and instrumentally, via measuring fast integrated air temperature in the optical path, or via enclosing the open-path instrument into a low-power short-intake design. Here we provide an alternative way to minimize or eliminate open-path heating effect, achieved by minimizing or eliminating the temperature gradient between the instrument surface and ambient air. Open-path low temperature controlled design is discussed in comparison with two other approaches (e.g., traditional open-path design and closed-path design) in terms of their field performance for Eddy Covariance flux measurements in the cold. This study presents field data from a new open-path CO2/H2O gas analyzer, LI-7500A, based on the LI-7500 model modified to produce substantially less heat during extremely cold conditions. Two regiments of the temperature control for internal electronics were examined across a wide range of temperatures: (i) the traditional control temperature of about 30oC, and (ii) new regiment controlling parts of internal electronics at 5oC. When new 5oC regiment was activated, the following changes were observed: heat dissipation from the surface reduced several folds, surface-to-air temperature gradients reduced 2-50 times; and the number of false uptake hours were reduced by 3.5 times, to the same level as a closed-path standard. Significant advantage of the new regiment was also observed in the magnitude of CO2 fluxes, especially in cold weather below -10oC. At such cold temperatures, CO2 fluxes from a 30oC controlled LI-7500 were 19% below those of the closed-path standard, while fluxes from a 5oC controlled LI-7500A were, on average, within 1% of the standard. These are strong experimental evidence that open-path instrument heating can be substantially reduced or eliminated via such simple hardware based solution. This allows continued and expanded use of this ultimately lowest-power remote solution for fast gas measurements.

  2. Quantification of Atmospheric Formaldehyde by Near-Infrared Cavity Ring-Down Spectroscopy

    NASA Astrophysics Data System (ADS)

    Rella, C.; Hoffnagle, J.; Fleck, D.; Kim-Hak, D.

    2017-12-01

    Formaldehyde is an important species in atmospheric chemistry, especially in urban environments, where it is a decay product of methane and volatile hydrocarbons. It is also a toxic, carcinogenic compound that can contaminate ambient air from incomplete combustion, or outgassing of commercial products such as adhesives used to fabricate plywood or to affix indoor carpeting. Formaldehyde has a clearly resolved ro-vibrational absorption spectrum that is well-suited to optical analysis of formaldehyde concentration. We describe an instrument based on cavity ring-down spectroscopy for the quantitative analysis of formaldehyde concentration in ambient air. The instrument has a precision (1-sigma) of about 1 ppb at a measurement rate of 1 second, and provides measurements of less than 100 ppt with averaging. The instrument provides stable measurements (drift < 1 ppb) over long periods of time (days). The instrument has been ruggedized for mobile applications, and with a fast response time of a couple of seconds, it is suitable for ground-based vehicle deployments for fenceline monitoring of formaldehyde emissions. In addition, we report on ambient atmospheric measurements at a 10m urban tower, which demonstrate the suitability of the instrument for applications in atmospheric chemistry.

  3. Inter-comparison of laser photoacoustic spectroscopy and gas chromatography techniques for measurements of ethene in the atmosphere.

    PubMed

    Kuster, William C; Harren, Frans J M; de Gouw, Joost A

    2005-06-15

    Laser photoacoustic spectroscopy (LPAS) is highly suitable for the detection of ethene in air due to the overlap between its strongest absorption lines and the wavelengths accessible by high-powered CO2 lasers. Here, we test the ability of LPAS to measure ethene in ambient air by comparing the measurements in urban air with those from a gas chromatography flame-ionization detection (GC-FID) instrument. Over the course of several days, we obtained quantitative agreement between the two measurements. Over this period, the LPAS instrument had a positive offset of 330 +/- 140 pptv (parts-per-trillion by volume) relative to the GC-FID instrument, possibly caused by interference from other species. The detection limit of the LPAS instrument is currently estimated around 1 ppbv and is limited by this offset and the statistical noise in the data. We conclude that LPAS has the potential to provide fast-response measurements of ethene in the atmosphere, with significant advantages over existing techniques when measuring from moving platforms and in the vicinity of emission sources.

  4. From nanoparticles to large aerosols: Ultrafast measurement methods for size and concentration

    NASA Astrophysics Data System (ADS)

    Keck, Lothar; Spielvogel, Jürgen; Grimm, Hans

    2009-05-01

    A major challenge in aerosol technology is the fast measurement of number size distributions with good accuracy and size resolution. The dedicated instruments are frequently based on particle charging and electric detection. Established fast systems, however, still feature a number of shortcomings. We have developed a new instrument that constitutes of a high flow Differential Mobility Analyser (high flow DMA) and a high sensitivity Faraday Cup Electrometer (FCE). The system enables variable flow rates of up to 150 lpm, and the scan time for size distribution can be shortened considerably due to the short residence time of the particles in the DMA. Three different electrodes can be employed in order to cover a large size range. First test results demonstrate that the scan time can be reduced to less than 1 s for small particles, and that the results from the fast scans feature no significant difference to the results from established slow method. The fields of application for the new instrument comprise the precise monitoring of fast processes with nanoparticles, including monitoring of engine exhaust in automotive research.

  5. A tangentially viewing fast ion D-alpha diagnostic for NSTX.

    PubMed

    Bortolon, A; Heidbrink, W W; Podestà, M

    2010-10-01

    A second fast ion D-alpha (FIDA) installation is planned at NSTX to complement the present perpendicular viewing FIDA diagnostics. Following the present diagnostic scheme, the new diagnostic will consist of two instruments: a spectroscopic diagnostic that measures fast ion spectra and profiles at 16 radial points with 5-10 ms resolution and a system that uses a band pass filter and photomultiplier to measure changes in FIDA light with 50 kHz sampling rate. The new pair of FIDA instruments will view the heating beams tangentially. The viewing geometry minimizes spectral contamination by beam emission or edge sources of background emission. The improved velocity-space resolution will provide detailed information about neutral-beam current drive and about fast ion acceleration and transport by injected radio frequency waves and plasma instabilities.

  6. Replacing the AMOR with the miniDOAS in the ammonia monitoring network in the Netherlands

    NASA Astrophysics Data System (ADS)

    Berkhout, Augustinus J. C.; Swart, Daan P. J.; Volten, Hester; Gast, Lou F. L.; Haaima, Marty; Verboom, Hans; Stefess, Guus; Hafkenscheid, Theo; Hoogerbrugge, Ronald

    2017-11-01

    In this paper we present the continued development of the miniDOAS, an active differential optical absorption spectroscopy (DOAS) instrument used to measure ammonia concentrations in ambient air. The miniDOAS has been adapted for use in the Dutch National Air Quality Monitoring Network. The miniDOAS replaces the life-expired continuous-flow denuder ammonia monitor (AMOR). From September 2014 to December 2015, both instruments measured in parallel before the change from AMOR to miniDOAS was made. The instruments were deployed at six monitoring stations throughout the Netherlands. We report on the results of this intercomparison. Both instruments show a good uptime of ca. 90 %, adequate for an automatic monitoring network. Although both instruments produce 1 min values of ammonia concentrations, a direct comparison on short timescales such as minutes or hours does not give meaningful results because the AMOR response to changing ammonia concentrations is slow. Comparisons between daily and monthly values show good agreement. For monthly averages, we find a small average offset of 0.65 ± 0.28 µg m-3 and a slope of 1.034 ± 0.028, with the miniDOAS measuring slightly higher than the AMOR. The fast time resolution of the miniDOAS makes the instrument suitable not only for monitoring but also for process studies.

  7. Development and Reliability Testing of a Fast-Food Restaurant Observation Form.

    PubMed

    Rimkus, Leah; Ohri-Vachaspati, Punam; Powell, Lisa M; Zenk, Shannon N; Quinn, Christopher M; Barker, Dianne C; Pugach, Oksana; Resnick, Elissa A; Chaloupka, Frank J

    2015-01-01

    To develop a reliable observational data collection instrument to measure characteristics of the fast-food restaurant environment likely to influence consumer behaviors, including product availability, pricing, and promotion. The study used observational data collection. Restaurants were in the Chicago Metropolitan Statistical Area. A total of 131 chain fast-food restaurant outlets were included. Interrater reliability was measured for product availability, pricing, and promotion measures on a fast-food restaurant observational data collection instrument. Analysis was done with Cohen's κ coefficient and proportion of overall agreement for categorical variables and intraclass correlation coefficient (ICC) for continuous variables. Interrater reliability, as measured by average κ coefficient, was .79 for menu characteristics, .84 for kids' menu characteristics, .92 for food availability and sizes, .85 for beverage availability and sizes, .78 for measures on the availability of nutrition information,.75 for characteristics of exterior advertisements, and .62 and .90 for exterior and interior characteristics measures, respectively. For continuous measures, average ICC was .88 for food pricing measures, .83 for beverage prices, and .65 for counts of exterior advertisements. Over 85% of measures demonstrated substantial or almost perfect agreement. Although some measures required revision or protocol clarification, results from this study suggest that the instrument may be used to reliably measure the fast-food restaurant environment.

  8. Calibration techniques for a fast duo-spectrometer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chapman, J.T.; Den Hartog, D.J.

    1996-06-01

    The authors have completed the upgrade and calibration of the Ion Dynamics Spectrometer (IDS), a high-speed Doppler duo-spectrometer which measures ion flow and temperature in the MST Reversed-field Pinch. This paper describes an in situ calibration of the diagnostic`s phase and frequency response. A single clock was employed to generate both a digital test signal and a digitizer trigger thus avoiding frequency drift and providing a highly resolved measurement over the system bandwidth. Additionally, they review the measurement of the spectrometer instrument function and absolute intensity response. This calibration and subsequent performance demonstrate the IDS to be one of themore » fastest, highest throughput diagnostics of its kind. Typical measurements are presented.« less

  9. QuickPol: Fast calculation of effective beam matrices for CMB polarization

    NASA Astrophysics Data System (ADS)

    Hivon, Eric; Mottet, Sylvain; Ponthieu, Nicolas

    2017-02-01

    Current and planned observations of the cosmic microwave background (CMB) polarization anisotropies, with their ever increasing number of detectors, have reached a potential accuracy that requires a very demanding control of systematic effects. While some of these systematics can be reduced in the design of the instruments, others will have to be modeled and hopefully accounted for or corrected a posteriori. We propose QuickPol, a quick and accurate calculation of the full effective beam transfer function and of temperature to polarization leakage at the power spectra level, as induced by beam imperfections and mismatches between detector optical and electronic responses. All the observation details such as exact scanning strategy, imperfect polarization measurements, and flagged samples are accounted for. Our results are validated on Planck high frequency instrument (HFI) simulations. We show how the pipeline can be used to propagate instrumental uncertainties up to the final science products, and could be applied to experiments with rotating half-wave plates.

  10. 78 FR 64916 - Application(s) for Duty-Free Entry of Scientific Instruments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-30

    ...., light to heat), crystallization, melting, phase transformations, fracture, and other dynamic events. The... Sciences University, 1120 15th Street, Augusta, GA 30912. Instrument: Imaging System/Digital Microscope... the instrument include fast wavelength change, a dichromotome system, and two different light sources...

  11. Evaluation of the Light-Cycler® SeptiFast Test in Newborns With Suspicion of Nosocomial Sepsis

    PubMed Central

    Ortiz Ibarra, Javier; Trevino Valdez, Pablo; Valenzuela Mendez, Ema; Limon Rojas, Ana; Lara Flores, Gabriel; Ceballos Bocanegra, Adrian; Morales Mendez, Iyari; Fernandez Carrocera, Luis; Covian Molina, Emilia; Reyna Figueroa, Jesus

    2015-01-01

    Background: Nosocomial sepsis (NS) in newborns (NBs) is associated with high mortality rates and low microbial recovery rates. To overcome the latter problem, new techniques in molecular biology are being used. Objectives: To evaluate the diagnostic efficacy of SeptiFast test for the diagnosis of nosocomial sepsis in the newborn. Materials and Methods: 86 blood specimens of NBs with suspected NS (NOSEP-1 Test > 8 points) were analyzed using Light Cycler SeptiFast (LC-SF) a real-time multiplex PCR instrument. The results were analyzed with the Roche SeptiFast Identification Software. Another blood sample was collected to carry out a blood culture (BC). Results: Sensitivity (Sn) and specificity (Sp) of 0.69 and 0.65 respectively, compared with blood culture (BC) were obtained for LC-SF. Kappa index concordance between LC-SF and BC was 0.21. Thirteen (15.11%) samples were BC positive and 34 (31.39%) were positive with LC-SF tests. Conclusions: Compared with BC, LC-SF allows the detection of a greater number of pathogenic species in a small blood sample (1 mL) with a shorter response time. PMID:26199693

  12. REVIEW ARTICLE: Emission measurement techniques for advanced powertrains

    NASA Astrophysics Data System (ADS)

    Adachi, Masayuki

    2000-10-01

    Recent developments in high-efficiency low-emission powertrains require the emission measurement technologies to be able to detect regulated and unregulated compounds with very high sensitivity and a fast response. For example, levels of a variety of nitrogen compounds and sulphur compounds should be analysed in real time in order to develop aftertreatment systems to decrease emission of NOx for the lean burning powertrains. Also, real-time information on the emission of particulate matter for the transient operation of diesel engines and direct injection gasoline engines is invaluable. The present paper reviews newly introduced instrumentation for such emission measurement that is demanded for the developments in advanced powertrain systems. They include Fourier transform infrared spectroscopy, mass spectrometry and fast response flame ionization detection. In addition, demands and applications of the fuel reformer developments for fuel cell electric vehicles are discussed. Besides the detection methodologies, sample handling techniques for the measurement of concentrations emitted from low emission vehicles for which the concentrations of the pollutants are significantly lower than the concentrations present in ambient air, are also described.

  13. 75 FR 82372 - Application(s) for Duty-Free Entry of Scientific Instruments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-30

    ..., Argonne LLC, 9700 South Cass Ave., Lemont, IL 60439. Instrument: Pilatus 100K Pixel Detector System... efficiency (no readout noise and direct detection scheme), high dynamic range (20-bits), and fast readout.... Instrument: Pilatus 300K Pixel Detector System. Manufacturer: Dectris Ltd., Switzerland. Intended Use: The...

  14. Field Micrometeorological Measurements, Process-Level Studies and Modeling of Methane and Carbon Dioxide Fluxes in a Boreal Wetland Ecosystem

    NASA Technical Reports Server (NTRS)

    Verma, S. B.; Arkebauer, T. J.; Ullman, F. G.; Valentine, D. W.; Parton, W. J.; Schimel, D. S.

    1998-01-01

    The main instrumentation platform consisted of eddy correlation sensors mounted on a scaffold tower at a height of 4.2 m above the peat surface. The sensors were attached to a boom assembly which could be rotated into the prevailing winds. The boom assembly was mounted on a movable sled which, when extended, allowed sensors to be up to 2 m away from the scaffolding structure to minimize flow distortion. When retracted, the sensors could easily be installed, serviced or rotated. An electronic level with linear actuators allowed the sensors to be remotely levelled once the sled was extended. Two instrument arrays were installed. A primary (fast-response) array consisted of a three-dimensional sonic anemometer, a methane sensor (tunable diode laser spectrometer), a carbon dioxide/water vapor sensor, a fine wire thermocouple and a backup one-dimensional sonic anemometer. The secondary array consisted of a one-dimensional sonic anemometer, a fine wire thermocouple and a Krypton hygrometer. Descriptions of these sensors may be found in other reports (e.g., Verma; Suyker and Verma). Slow-response sensors provided supporting measurements including mean air temperature and humidity, mean horizontal windspeed and direction, incoming and reflected solar radiation, net radiation, incoming and reflected photosynthetically active radiation (PAR), soil heat flux, peat temperature, water-table elevation and precipitation. A data acquisition system (consisting of an IBM compatible microcomputer, amplifiers and a 16 bit analog-to-digital converter), housed in a small trailer, was used to record the fast response signals. These signals were low-pass filtered (using 8-pole Butterworth active filters with a 12.5 Hz cutoff frequency) and sampled at 25 Hz. Slow-response signals were sampled every 5 s using a network of CR21X (Campbell Scientific, Inc., Logan Utah) data loggers installed in the fen. All signals were averaged over 30-minute periods (runs).

  15. 1987 Nuclear Science Symposium, 34th, and 1987 Symposium on Nuclear Power Systems, 19th, San Francisco, CA, Oct. 21-23, 1987, Proceedings

    NASA Astrophysics Data System (ADS)

    Armantrout, Guy A.

    1988-02-01

    The present conference consideres topics in radiation detectors, advanced electronic circuits, data acquisition systems, radiation detector systems, high-energy and nuclear physics radiation detection, spaceborne instrumentation, health physics and environmental radiation detection, nuclear medicine, nuclear well logging, and nuclear reactor instrumentation. Attention is given to the response of scintillators to heavy ions, phonon-mediated particle detection, ballistic deficits in pulse-shaping amplifiers, fast analog ICs for particle physics, logic cell arrays, the CERN host interface, high performance data buses, a novel scintillating glass for high-energy physics applications, background events in microchannel plates, a tritium accelerator mass spectrometer, a novel positron tomograph, advancements in PET, cylindrical positron tomography, nuclear techniques in subsurface geology, REE borehole neutron activation, and a continuous tritium monitor for aqueous process streams.

  16. Nonintrusive fast response oxygen monitoring system for high temperature flows

    NASA Technical Reports Server (NTRS)

    Oh, Daniel B.; Stanton, Alan C.

    1993-01-01

    A new technique has been developed for nonintrusive in situ measurement of oxygen concentration, gas temperature, and flow velocity of the test media in hypersonic wind tunnels. It is based on absorption of near-infrared radiation from inexpensive GaAlAs laser diodes used in optoelectronics industry. It is designed for simultaneous measurements along multiple lines of sight accessed by fiber optics. Molecular oxygen concentration is measured from the magnitude of absorption signals; rotational gas temperature is measured from the intensity ratio of two oxygen absorption lines; and the flow velocity is measured from the Doppler shift of the absorption line positions. This report describes the results of an extensive series of tests of the prototype instrument in laboratory flames emphasizing assessment of the instruments capabilities for quantitative measurement of O2 concentration (mole fraction) and gas temperature.

  17. Light output function and assembly of the time-of-flight enhanced diagnostics neutron spectrometer plastic scintillators for background reduction by double kinematic selection at EAST

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peng, X. Y.; Chen, Z. J.; Zhang, X.

    The 2.5 MeV neutron spectrometer TOFED (Time-Of-Flight Enhanced Diagnostics) has been constructed to perform advanced neutron emission spectroscopy diagnosis of deuterium plasmas on EAST. The instrument has a double-ring structure which, in combination with pulse shape digitization, allows for a dual kinematic selection in the time-of-flight/recoil proton energy (tof/E{sub p}) space, thus improving the spectrometer capability to resolve fast ion signatures in the neutron spectrum, in principle up to a factor ≈100. The identification and separation of features from the energetic ions in the neutron spectrum depends on the detailed knowledge of the instrument response function, both in terms ofmore » the light output function of the scintillators and the effect of undesired multiple neutron scatterings in the instrument. This work presents the determination of the light output function of the TOFED plastic scintillator detectors and their geometrical assembly. Results from dedicated experiments with γ-ray sources and quasi-monoenergetic neutron beams are presented. Implications on the instrument capability to perform background suppression based on double kinematic selection are discussed.« less

  18. Identifying developmental coordination disorder: MOQ-T validity as a fast screening instrument based on teachers' ratings and its relationship with praxic and visuospatial working memory deficits.

    PubMed

    Giofrè, David; Cornoldi, Cesare; Schoemaker, Marina M

    2014-12-01

    The present study was devoted to test the validity of the Italian adaptation of the Motor Observation Questionnaire for Teachers (MOQ-T, Schoemaker, Flapper, Reinders-Messelink, & De Kloet, 2008) as a fast screening instrument, based on teachers' ratings, for detecting developmental coordination disorders symptoms and to study its relationship with praxic and visuospatial working memory deficits. In a first study on a large sample of children, we assessed the reliability and structure of the Italian adaptation of the MOQ-T. Results showed a good reliability of the questionnaire and a hierarchical structure with two first-order factors (reflecting motor and handwriting skills), which are influenced by a second-order factor (general motor function) at the top. In a second study, we looked at the external validity of the MOQ-T and found that children with symptoms of Developmental Coordination Disorder (children with high scores on the MOQ-T) also had difficulty reproducing gestures, either imitating others or in response to verbal prompts. Our results also showed that children with high MOQ-T scores had visuospatial WM impairments. The theoretical and clinical implications of these findings are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Older adults benefit from music training early in life: biological evidence for long-term training-driven plasticity.

    PubMed

    White-Schwoch, Travis; Woodruff Carr, Kali; Anderson, Samira; Strait, Dana L; Kraus, Nina

    2013-11-06

    Aging results in pervasive declines in nervous system function. In the auditory system, these declines include neural timing delays in response to fast-changing speech elements; this causes older adults to experience difficulty understanding speech, especially in challenging listening environments. These age-related declines are not inevitable, however: older adults with a lifetime of music training do not exhibit neural timing delays. Yet many people play an instrument for a few years without making a lifelong commitment. Here, we examined neural timing in a group of human older adults who had nominal amounts of music training early in life, but who had not played an instrument for decades. We found that a moderate amount (4-14 years) of music training early in life is associated with faster neural timing in response to speech later in life, long after training stopped (>40 years). We suggest that early music training sets the stage for subsequent interactions with sound. These experiences may interact over time to sustain sharpened neural processing in central auditory nuclei well into older age.

  20. Older Adults Benefit from Music Training Early in Life: Biological Evidence for Long-Term Training-Driven Plasticity

    PubMed Central

    White-Schwoch, Travis; Carr, Kali Woodruff; Anderson, Samira; Strait, Dana L.

    2013-01-01

    Aging results in pervasive declines in nervous system function. In the auditory system, these declines include neural timing delays in response to fast-changing speech elements; this causes older adults to experience difficulty understanding speech, especially in challenging listening environments. These age-related declines are not inevitable, however: older adults with a lifetime of music training do not exhibit neural timing delays. Yet many people play an instrument for a few years without making a lifelong commitment. Here, we examined neural timing in a group of human older adults who had nominal amounts of music training early in life, but who had not played an instrument for decades. We found that a moderate amount (4–14 years) of music training early in life is associated with faster neural timing in response to speech later in life, long after training stopped (>40 years). We suggest that early music training sets the stage for subsequent interactions with sound. These experiences may interact over time to sustain sharpened neural processing in central auditory nuclei well into older age. PMID:24198359

  1. The effect of fast-food availability on fast-food consumption and obesity among rural residents: an analysis by race/ethnicity.

    PubMed

    Dunn, Richard A; Sharkey, Joseph R; Horel, Scott

    2012-01-01

    Rural areas of the United States tend to have higher obesity rates than urban areas, particularly in regions with high proportions of non-white residents. This paper analyzes the effect of fast-food availability on the level of fast-food consumption and obesity risk among both white and non-white residents of central Texas. Potential endogeneity of fast-food availability is addressed through instrumental variables regression using distance to the nearest major highway as an instrument. We find that non-whites tend to exhibit higher obesity rates, greater access to fast-food establishments and higher consumption of fast-food meals compared to their white counterparts. In addition, we found that whites and non-whites respond differently to the availability of fast-food in rural environments. Greater availability is not associated with either greater consumption of fast-food meals or a higher obesity risk among the sample of whites. In contrast, greater availability of fast-food is positively associated with both the number of meals consumed for non-white rural residents and their obesity. While our results are robust to specification, the effect of availability on weight outcomes is notably weaker when indirectly calculated from the implied relationship between consumption and caloric intake. This highlights the importance of directly examining the proposed mechanism through which an environmental factor influences weight outcomes. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Fast simulation of the NICER instrument

    NASA Astrophysics Data System (ADS)

    Doty, John P.; Wampler-Doty, Matthew P.; Prigozhin, Gregory Y.; Okajima, Takashi; Arzoumanian, Zaven; Gendreau, Keith

    2016-07-01

    The NICER1 mission uses a complicated physical system to collect information from objects that are, by x-ray timing science standards, rather faint. To get the most out of the data we will need a rigorous understanding of all instrumental effects. We are in the process of constructing a very fast, high fidelity simulator that will help us to assess instrument performance, support simulation-based data reduction, and improve our estimates of measurement error. We will combine and extend existing optics, detector, and electronics simulations. We will employ the Compute Unified Device Architecture (CUDA2) to parallelize these calculations. The price of suitable CUDA-compatible multi-giga op cores is about $0.20/core, so this approach will be very cost-effective.

  3. Cherenkov and Scintillation Properties of Cubic Zirconium

    NASA Technical Reports Server (NTRS)

    Christl, M.J.; Adams, J.H.; Parnell, T.A.; Kuznetsov, E.N.

    2008-01-01

    Cubic zirconium (CZ) is a high index of refraction (n =2.17) material that we have investigated for Cherenkov counter applications. Laboratory and proton accelerator tests of an 18cc sample of CZ show that the expected fast Cherenkov response is accompanied by a longer scintillation component that can be separated by pulse shaping. This presents the possibility of novel particle spectrometers which exploits both properties of CZ. Other high index materials being examined for Cherenkov applications will be discussed. Results from laboratory tests and an accelerator exposure will be presented and a potential application in solar energetic particle instruments will be discussed

  4. Detecting Bioaerosols When Time Is of the Essence

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hazi, A

    About seven years ago, Livermore researchers received seed funding from the Laboratory Directed Research and Development Program to develop an instrument that counters bioterrorism by providing a rapid early warning system for pathogens, such as anthrax. (See S&TR, January/February 2002, pp. 24-26.) That instrument, the Autonomous Pathogen Detection System (APDS), is now ready for deployment to better protect the public from a bioaerosol attack, and the development team has been honored with a 2004 R&D 100 Award. The lectern-size APDS can be placed in airports, office buildings, performing arts centers, mass transit systems, sporting arenas--anywhere an attack might be launched.more » APDS was designed to get results fast and get them right, without false positives. Biological scientist Richard Langlois, who spearheaded the APDS development effort, explains, ''The system provides results on the spot. Faster results allow a faster emergency response, which in the end means saving lives.''« less

  5. Fast multichannel astronomical photometer based on silicon photo multipliers mounted at the Telescopio Nazionale Galileo

    NASA Astrophysics Data System (ADS)

    Ambrosino, Filippo; Meddi, Franco; Rossi, Corinne; Sclavi, Silvia; Nesci, Roberto; Bruni, Ivan; Ghedina, Adriano; Riverol, Luis; Di Fabrizio, Luca

    2014-07-01

    The realization of low-cost instruments with high technical performance is a goal that deserves efforts in an epoch of fast technological developments. Such instruments can be easily reproduced and therefore allow new research programs to be opened in several observatories. We realized a fast optical photometer based on the SiPM (Silicon Photo Multiplier) technology, using commercially available modules. Using low-cost components, we developed a custom electronic chain to extract the signal produced by a commercial MPPC (Multi Pixel Photon Counter) module produced by Hamamatsu Photonics to obtain sub-millisecond sampling of the light curve of astronomical sources (typically pulsars). We built a compact mechanical interface to mount the MPPC at the focal plane of the TNG (Telescopio Nazionale Galileo), using the space available for the slits of the LRS (Low Resolution Spectrograph). On February 2014 we observed the Crab pulsar with the TNG with our prototype photometer, deriving its period and the shape of its light curve, in very good agreement with the results obtained in the past with other much more expensive instruments. After the successful run at the telescope we describe here the lessons learned and the ideas that burst to optimize this instrument and make it more versatile.

  6. Intensity-Stabilized Fast-Scanned Direct Absorption Spectroscopy Instrumentation Based on a Distributed Feedback Laser with Detection Sensitivity down to 4 × 10−6

    PubMed Central

    Zhao, Gang; Tan, Wei; Jia, Mengyuan; Hou, Jiajuan; Ma, Weiguang; Dong, Lei; Zhang, Lei; Feng, Xiaoxia; Wu, Xuechun; Yin, Wangbao; Xiao, Liantuan; Axner, Ove; Jia, Suotang

    2016-01-01

    A novel, intensity-stabilized, fast-scanned, direct absorption spectroscopy (IS-FS-DAS) instrumentation, based on a distributed feedback (DFB) diode laser, is developed. A fiber-coupled polarization rotator and a fiber-coupled polarizer are used to stabilize the intensity of the laser, which significantly reduces its relative intensity noise (RIN). The influence of white noise is reduced by fast scanning over the spectral feature (at 1 kHz), followed by averaging. By combining these two noise-reducing techniques, it is demonstrated that direct absorption spectroscopy (DAS) can be swiftly performed down to a limit of detection (LOD) (1σ) of 4 × 10−6, which opens up a number of new applications. PMID:27657082

  7. Assessment of Sensor Technologies for Advanced Reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Korsah, Kofi; Kisner, R. A.; Britton Jr., C. L.

    This paper provides an assessment of sensor technologies and a determination of measurement needs for advanced reactors (AdvRx). It is a summary of a study performed to provide the technical basis for identifying and prioritizing research targets within the instrumentation and control (I&C) Technology Area under the Department of Energy’s (DOE’s) Advanced Reactor Technology (ART) program. The study covered two broad reactor technology categories: High Temperature Reactors and Fast Reactors. The scope of “High temperature reactors” included Gen IV reactors whose coolant exit temperatures exceed ≈650 °C and are moderated (as opposed to fast reactors). To bound the scope formore » fast reactors, this report reviewed relevant operating experience from US-operated Sodium Fast Reactor (SFR) and relevant test experience from the Fast Flux Test Facility (FFTF). For high temperature reactors the study showed that in many cases instrumentation have performed reasonably well in research and demonstration reactors. However, even in cases where the technology is “mature” (such as thermocouples), HTGRs can benefit from improved technologies. Current HTGR instrumentation is generally based on decades-old technology and adapting newer technologies could provide significant advantages. For sodium fast reactors, the study found that several key research needs arise around (1) radiation-tolerant sensor design for in-vessel or in-core applications, where possible non-invasive sensing approaches for key parameters that minimize the need to deploy sensors in-vessel, (2) approaches to exfiltrating data from in-vessel sensors while minimizing penetrations, (3) calibration of sensors in-situ, and (4) optimizing sensor placements to maximize the information content while minimizing the number of sensors needed.« less

  8. Use of vacuum tubes in test instrumentation for measuring characteristics of fast high-voltage semiconductor devices

    NASA Technical Reports Server (NTRS)

    Berning, D.

    1981-01-01

    Circuits are described that permit measurement of fast events occurring in power semiconductors. These circuits were developed for the dynamic characterization of transistors used in inductive-load switching applications. Fast voltage clamping using vacuum diodes is discussed, and reference is made to a unique circuit that was built for performing nondestructive, reverse-bias, second-breakdown tests on transistors.

  9. Construction, Instrumentation, and Testing of Fast-Setting Hydraulic Cement Concrete in Palmdale, California

    DOT National Transportation Integrated Search

    2000-08-01

    To minimize the lane closure time for construction, Caltrans is exploring the use of fast-setting hydraulic cement concrete (FSHCC). The principal property of the FSHCC is its high early strength gain. This accelerated strength gain would increase th...

  10. The influence of market deregulation on fast food consumption and body mass index: a cross-national time series analysis.

    PubMed

    De Vogli, Roberto; Kouvonen, Anne; Gimeno, David

    2014-02-01

    To investigate the effect of fast food consumption on mean population body mass index (BMI) and explore the possible influence of market deregulation on fast food consumption and BMI. The within-country association between fast food consumption and BMI in 25 high-income member countries of the Organisation for Economic Co-operation and Development between 1999 and 2008 was explored through multivariate panel regression models, after adjustment for per capita gross domestic product, urbanization, trade openness, lifestyle indicators and other covariates. The possible mediating effect of annual per capita intake of soft drinks, animal fats and total calories on the association between fast food consumption and BMI was also analysed. Two-stage least squares regression models were conducted, using economic freedom as an instrumental variable, to study the causal effect of fast food consumption on BMI. After adjustment for covariates, each 1-unit increase in annual fast food transactions per capita was associated with an increase of 0.033 kg/m2 in age-standardized BMI (95% confidence interval, CI: 0.013-0.052). Only the intake of soft drinks--not animal fat or total calories--mediated the observed association (β: 0.030; 95% CI: 0.010-0.050). Economic freedom was an independent predictor of fast food consumption (β: 0.27; 95% CI: 0.16-0.37). When economic freedom was used as an instrumental variable, the association between fast food and BMI weakened but remained significant (β: 0.023; 95% CI: 0.001-0.045). Fast food consumption is an independent predictor of mean BMI in high-income countries. Market deregulation policies may contribute to the obesity epidemic by facilitating the spread of fast food.

  11. The design and characterization of a digital optical breast cancer imaging system.

    PubMed

    Flexman, Molly L; Li, Yang; Bur, Andres M; Fong, Christopher J; Masciotti, James M; Al Abdi, Rabah; Barbour, Randall L; Hielscher, Andreas H

    2008-01-01

    Optical imaging has the potential to play a major role in breast cancer screening and diagnosis due to its ability to image cancer characteristics such as angiogenesis and hypoxia. A promising approach to evaluate and quantify these characteristics is to perform dynamic imaging studies in which one monitors the hemodynamic response to an external stimulus, such as a valsalva maneuver. It has been shown that the response to such stimuli shows MARKED differences between cancerous and healthy tissues. The fast imaging rates and large dynamic range of digital devices makes them ideal for this type of imaging studies. Here we present a digital optical tomography system designed specifically for dynamic breast imaging. The instrument uses laser diodes at 4 different near-infrared wavelengths with 32 sources and 128 silicon photodiode detectors.

  12. Measuring Fluorescent Dye in the Bubbly and Sediment-Laden Surfzone

    DTIC Science & Technology

    2009-04-16

    damage instrumentation, hamper deployment, and render many oceanographic instruments and platforms (i.e., boats) unusable. Breaking waves intermit ...fluo- rometer system. The jet ski allows fast repeated cross- and alongshore transects though the sur- fzone where traditional boats and submersibles

  13. Two Dual Ion Spectrometer Flight Units of the Fast Plasma Instrument Suite (FPI) for the Magnetospheric Multiscale Mission (MMS)

    NASA Technical Reports Server (NTRS)

    Adams, Mitzi

    2014-01-01

    Two Dual Ion Spectrometer flight units of the Fast Plasma Instrument Suite (FPI) for the Magnetospheric Multiscale Mission (MMS) have returned to MSFC for flight testing. Anticipated to begin on June 30, tests will ensue in the Low Energy Electron and Ion Facility of the Heliophysics and Planetary Science Office (ZP13), managed by Dr. Victoria Coffey of the Natural Environments Branch of the Engineering Directorate (EV44). The MMS mission consists of four identical spacecraft, whose purpose is to study magnetic reconnection in the boundary regions of Earth's magnetosphere.

  14. Two-years of In-flight Spectrometer Calibration Results for the Fast Plasma Investigation (FPI) on the Magmetospheric Multiscale (MMS) Mission

    NASA Astrophysics Data System (ADS)

    Schiff, C.; Gershman, D. J.; Avanov, L. A.; Giles, B. L.; Paterson, W. R.; Kriesler, S.; Barrie, A. C.; Rand, D. K.; Gliese, U.; Burch, J.

    2017-12-01

    Scientifically accurate measurements depend on careful calibration of in-flight instrumentation. We review two years of calibration results for the Fast Plasma Investigation (FPI) electron and ion spectrometers over the MMS fleet. We focus on the operating point calibration by which the operating voltage on each of the 64 spectrometers is set to best balance between gain, signal loss, and anode-to-anode cross talk. In addition, we map the calibration and housekeeping telemetry to infer charge extracted evolution from the microchannel plates and, subsequently, the project lifetime of the instrumentation.

  15. A Regularized Neural Net Approach for Retrieval of Atmospheric and Surface Temperatures with the IASI Instrument

    NASA Technical Reports Server (NTRS)

    Aires, F.; Chedin, A.; Scott, N. A.; Rossow, W. B.; Hansen, James E. (Technical Monitor)

    2001-01-01

    Abstract In this paper, a fast atmospheric and surface temperature retrieval algorithm is developed for the high resolution Infrared Atmospheric Sounding Interferometer (IASI) space-borne instrument. This algorithm is constructed on the basis of a neural network technique that has been regularized by introduction of a priori information. The performance of the resulting fast and accurate inverse radiative transfer model is presented for a large divE:rsified dataset of radiosonde atmospheres including rare events. Two configurations are considered: a tropical-airmass specialized scheme and an all-air-masses scheme.

  16. Superconducting High Resolution Fast-Neutron Spectrometers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hau, Ionel Dragos

    2006-01-01

    Superconducting high resolution fast-neutron calorimetric spectrometers based on 6LiF and TiB{sub 2} absorbers have been developed. These novel cryogenic spectrometers measure the temperature rise produced in exothermal (n, α) reactions with fast neutrons in 6Li and 10B-loaded materials with heat capacity C operating at temperatures T close to 0.1 K. Temperature variations on the order of 0.5 mK are measured with a Mo/Cu thin film multilayer operated in the transition region between its superconducting and its normal state. The advantage of calorimetry for high resolution spectroscopy is due to the small phonon excitation energies k BT on the order ofmore » μeV that serve as signal carriers, resulting in an energy resolution ΔE ~ (k BT 2C) 1/2, which can be well below 10 keV. An energy resolution of 5.5 keV has been obtained with a Mo/Cu superconducting sensor and a TiB 2 absorber using thermal neutrons from a 252Cf neutron source. This resolution is sufficient to observe the effect of recoil nuclei broadening in neutron spectra, which has been related to the lifetime of the first excited state in 7Li. Fast-neutron spectra obtained with a 6Li-enriched LiF absorber show an energy resolution of 16 keV FWHM, and a response in agreement with the 6Li(n, α) 3H reaction cross section and Monte Carlo simulations for energies up to several MeV. The energy resolution of order of a few keV makes this novel instrument applicable to fast-neutron transmission spectroscopy based on the unique elemental signature provided by the neutron absorption and scattering resonances. The optimization of the energy resolution based on analytical and numerical models of the detector response is discussed in the context of these applications.« less

  17. Trace Gas Quantification with Small Unmanned Aerial Systems

    NASA Astrophysics Data System (ADS)

    Schuyler, T. J.; Guzman, M. I.; Bailey, S.; Jacob, J.

    2017-12-01

    Measurements of atmospheric composition are generally performed with advanced instrumentation from ground stations using tall towers and weather balloons or with manned aircraft. Unmanned aerial systems (UAS) are a promising technology for atmospheric monitoring of trace atmospheric gases as they can bridge the gap between the regions of the atmospheric boundary layer measured by ground stations and aircraft. However, in general, the sophisticated instrumentation required for these measurements are heavy, preventing its deployment with small UAS. In order to successfully detect and quantify these gases, sensor packages aboard UAS must be lightweight, have low-power consumption, and possess limits of detection on the ppm scale or below with reasonably fast response times. Thus, a new generation of portable instrument is being developed in this work to meet these requirements employing new sensing packages. The cross sensitivity of these sensors to several gases is examined through laboratory testing of the instrument under variable environmental conditions prior to performing field measurements. Datasets include timestamps with position, temperature, relative humidity, pressure, along with variable mixing ratio values of important greenhouse gases. The work will present an analysis of the results gathered during authorized flights performed during the second CLOUD-MAP§ field campaign held in June 2017. §CLOUD-MAP: Collaboration Leading Operational UAS Development for Meteorology and Atmospheric Physics, a 4-year NSF funded effort.

  18. 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.

  19. Miniaturized low-cost ion mobility spectrometer for fast detection of chemical warfare agents.

    PubMed

    Zimmermann, Stefan; Barth, Sebastian; Baether, Wolfgang K M; Ringer, Joachim

    2008-09-01

    Ion mobility spectrometry (IMS) is a well-known method for detecting hazardous compounds in air. Typical applications are the detection of chemical warfare agents, highly toxic industrial compounds, explosives, and drugs of abuse. Detection limits in the low part per billion range, fast response times, and simple instrumentation make this technique more and more popular. In particular, there is an increasing demand for miniaturized low-cost IMS for hand-held devices and air monitoring of public areas by sensor networks. In this paper, we present a miniaturized aspiration condenser type ion mobility spectrometer for fast detection of chemical warfare agents. The device is easy to manufacture and allows single substance identification down to low part per billion-level concentrations within seconds. The improved separation power results from ion focusing by means of geometric constraints and fluid dynamics. A simple pattern recognition algorithm is used for the identification of trained substances in air. The device was tested at the German Armed Forces Scientific Institute for Protection Technologies-NBC-Protection. Different chemical warfare agents, such as sarin, tabun, soman, US-VX, sulfur mustard, nitrogen mustard, and lewisite were tested. The results are presented here.

  20. Scientific instrument engineering at Japanese congresses devoted to high-speed imaging

    NASA Astrophysics Data System (ADS)

    Shchelev, Mikhail Ya

    2011-06-01

    The information about the congresses held in Japan and devoted to fast imaging processes and photonics is presented. Reports devoted to the technique and the results of applications of superhigh-speed recording instrumentation in different fields of science and technology are considered.

  1. Monitoring food pathogens: Novel instrumentation for cassette PCR testing

    PubMed Central

    Hunt, Darin; Figley, Curtis; Lauzon, Jana; Figley, Rachel; Pilarski, Linda M.; McMullen, Lynn M.; Pilarski, Patrick M.

    2018-01-01

    In this manuscript, we report the design and development of a fast, reliable instrument to run gel-based cassette polymerase chain reactions (PCR). Here termed the GelCycler Mark II, our instrument is a miniaturized molecular testing system that is fast, low cost and sensitive. Cassette PCR utilizes capillary reaction units that carry all reagents needed for PCR, including primers and Taq polymerase, except the sample, which is loaded at the time of testing. Cassette PCR carries out real time quantitative PCR followed by melt curve analysis (MCA) to verify amplicon identity at the expected melt temperature (Tm). The cassette PCR technology is well developed, particularly for detecting pathogens, and has been rigorously validated for detecting pathogenic Escherichia coli in meat samples. However, the work has been hindered by the lack of a robust and stable instrument to carry out the PCR, which requires fast and accurate temperature regulation, improved light delivery and fluorescent recording, and faster PCR reactions that maintain a high sensitivity of detection. Here, we report design and testing of a new instrument to address these shortcomings and to enable standardized testing by cassette PCR and commercial manufacture of a robust and accurate instrument that can be mass produced to deliver consistent performance. As a corollary to our new instrument development, we also report the use of an improved design approach using a machined aluminum cassette to meet the new instrument standards, prevent any light bleed across different trenches in each cassette, and allow testing of a larger number of samples for more targets in a single run. The GelCycler Mark II can detect and report E. coli contamination in 41 minutes. Sample positives are defined in as having a melt curve comparable to the internal positive control, with peak height exceeding that of the internal negative control. In a fractional analysis, as little as 1 bacterium per capillary reaction unit is directly detectable, with no enrichment step, in 35 cycles of PCR/MCA, in a total time of 53 minutes, making this instrument and technology among the very best for speed and sensitivity in screening food for pathogenic contamination. PMID:29746561

  2. The IMUTUS interactive music tuition system

    NASA Astrophysics Data System (ADS)

    Tambouratzis, George; Bakamidis, Stelios; Dologlou, Ioannis; Carayannis, George; Dendrinos, Markos

    2002-05-01

    This presentation focuses on the IMUTUS project, which concerns the creation of an innovative method for training users on traditional musical instruments with no MIDI (Musical Instrument Digital Interface) output. The entities collaborating in IMUTUS are ILSP (coordinator), EXODUS, SYSTEMA, DSI, SMF, GRAME, and KTH. The IMUTUS effectiveness is enhanced via an advanced user interface incorporating multimedia techniques. Internet plays a pivotal role during training, the student receiving guidance over the net from a specially created teacher group. Interactiveness is emphasized via automatic-scoring tools, which provide fast yet accurate feedback to the user, while virtual reality methods assist the student in perfecting his technique. IMUTUS incorporates specialized recognition technology for the transformation of acoustic signals and music scores to MIDI format and incorporation in the training process. This process is enhanced by periodically enriching the score database, while customization to each user's requirements is supported. This work is partially supported by European Community under the Information Society Technology (IST) RTD programme. The authors are solely responsible for the content of this communication. It does not represent the opinion of the European Community, and the European Community is not responsible for any use that might be made of data appearing therein.

  3. Neutron-gamma flux and dose calculations for feasibility study of DISCOMS instrumentation in case of severe accident in a GEN 3 reactor

    NASA Astrophysics Data System (ADS)

    Brovchenko, Mariya; Duhamel, Isabelle; Dechenaux, Benjamin

    2017-09-01

    The present paper presents the study carried out in the frame of the DISCOMS project, which stands for "DIstributed Sensing for COrium Monitoring and Safety". This study concerns the calculation of the neutron and gamma radiations received by the considered instrumentation during the normal reactor operation as well as in case of a severe accident for the EPR reactor, outside the reactor pressure vessel and in the containment basemat. This paper summarizes the methods and hypotheses used for the particle transport simulation outside the vessel during normal reactor operation. The results of the simulations are then presented including the responses for distributed Optical Fiber Sensors (OFS), such as the gamma dose and the fast neutron fluence, and for Self Powered Neutron Detectors (SPNDs), namely the neutron and gamma spectra. Same responses are also evaluated for severe accident situations in order to design the SPNDs being sensitive to the both types of received neutron-gamma radiation. By contrast, fibers, involved as transducers in distributed OFS have to resist to the total radiation gamma dose and neutron fluence received during normal operation and the severe accident.

  4. Adaptive multiple super fast simulated annealing for stochastic microstructure reconstruction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ryu, Seun; Lin, Guang; Sun, Xin

    2013-01-01

    Fast image reconstruction from statistical information is critical in image fusion from multimodality chemical imaging instrumentation to create high resolution image with large domain. Stochastic methods have been used widely in image reconstruction from two point correlation function. The main challenge is to increase the efficiency of reconstruction. A novel simulated annealing method is proposed for fast solution of image reconstruction. Combining the advantage of very fast cooling schedules, dynamic adaption and parallelization, the new simulation annealing algorithm increases the efficiencies by several orders of magnitude, making the large domain image fusion feasible.

  5. A novel microcontroller-based digital instrument for measurement of electrical quantities under non-sinusoidal condition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anaya, O.; Moreno, G.E.L.; Madrigal, M.M.

    1999-11-01

    In the last years, several definitions of power have been proposed for more accurate measurement of electrical quantities in presence of harmonics pollution on power lines. Nevertheless, only few instruments have been constructed considering these definitions. This paper describes a new microcontroller-based digital instrument, which include definitions based on Harley Transform. The algorithms are fully processed using Fast Hartley Transform (FHT) and 16 bit-microcontroller platform. The constructed prototype was compared with commercial harmonics analyzer instrument.

  6. Use of acousto-optic tunable filter in fluorescence imaging endoscopy

    NASA Astrophysics Data System (ADS)

    Bouhifd, Mounir; Whelan, Maurice; Aprahamian, Marc

    2003-10-01

    A prototype instrument for fluorescence-based medical diagnostics in vivo is described. The system consists of a rigid endoscope comprising a UV laser-source for fluorescence excitation and a white light source for direct imaging. An acousto-optic tuneable filter (AOTF) is employed as a full-field tuneable bandpass filter. This allows fast continuous or random-access tuning with high filtering efficiency. A study of the diagnostic potential of fluorescence imaging for pancreatitis was conducted on a rat model. In particular, the aim was to detect autofluorescence of endogenous protoporphyrin IX (PpIX) that has been shown to accumulate in early-stage diseased tissue undergoing an inflammatory response.

  7. A study of stability effects in forested terrain

    NASA Astrophysics Data System (ADS)

    Desmond, Cian J.; Watson, Simon

    2014-12-01

    Data from four well instrumented met masts located in heavily forested European sites in different locations and terrain types are examined. Seven stability metrics are applied to the data sets and a novel method is used to identify the metric which most consistently identifies stability events of importance for wind energy generation. It was found that the Obukhov length, as calculated by fast response sonic anemometer, provides the most reliable results in these highly complex sites. It was also found that non-neutral stabilities can be expected a significant portion of the time for wind speeds of less than 10 m/s at the considered sites.

  8. A Planar Two-Dimensional Superconducting Bolometer Array for the Green Bank Telescope

    NASA Technical Reports Server (NTRS)

    Benford, Dominic; Staguhn, Johannes G.; Chervenak, James A.; Chen, Tina C.; Moseley, S. Harvey; Wollack, Edward J.; Devlin, Mark J.; Dicker, Simon R.; Supanich, Mark

    2004-01-01

    In order to provide high sensitivity rapid imaging at 3.3mm (90GHz) for the Green Bank Telescope - the world's largest steerable aperture - a camera is being built by the University of Pennsylvania, NASA/GSFC, and NRAO. The heart of this camera is an 8x8 close-packed, Nyquist-sampled detector array. We have designed and are fabricating a functional superconducting bolometer array system using a monolithic planar architecture. Read out by SQUID multiplexers, the superconducting transition edge sensors will provide fast, linear, sensitive response for high performance imaging. This will provide the first ever superconducting bolometer array on a facility instrument.

  9. Noninvasive vacuum integrity tests on fast warm-up traveling-wave tubes

    NASA Astrophysics Data System (ADS)

    Dallos, A.; Carignan, R. G.

    1989-04-01

    A method of tube vacuum monitoring that uses the tube's existing internal electrodes as an ion gage is discussed. This method has been refined using present-day instrumentation and has proved to be a precise, simple, and fast method of tube vacuum measurement. The method is noninvasive due to operation of the cathode at low temperature, which minimizes pumping or outgassing. Because of the low current levels to be measured, anode insulator leakage must be low, and the leads must be properly shielded to minimize charging effects. A description of the method, instrumentation used, limitations, and data showing results over a period of 600 days are presented.

  10. Topograph for inspection of engine cylinder walls.

    PubMed

    Franz, S; Leonhardt, K; Windecker, R; Tiziani, H J

    1999-12-20

    The microstructural inspection of engine cylinder walls is an important task for quality management in the automotive industry. Until recently, mainly tactile methods were used for this purpose. We present an optical instrument based on microscopic fringe projection that permits fast, reliable, and nondestructive measurements of microstructure. The field of view is 0.8 mm x 1.2 mm, with a spatial sampling of 1100 x 700 pixels. In contrast to conventional tactile sensors, the optical method provides fast in situ three-dimensional surface characterizations that provide more information about the surface than do line profiles. Measurements are presented, and advantages of this instrument for characterization of a surface are discussed.

  11. Fast-neutron, coded-aperture imager

    NASA Astrophysics Data System (ADS)

    Woolf, Richard S.; Phlips, Bernard F.; Hutcheson, Anthony L.; Wulf, Eric A.

    2015-06-01

    This work discusses a large-scale, coded-aperture imager for fast neutrons, building off a proof-of concept instrument developed at the U.S. Naval Research Laboratory (NRL). The Space Science Division at the NRL has a heritage of developing large-scale, mobile systems, using coded-aperture imaging, for long-range γ-ray detection and localization. The fast-neutron, coded-aperture imaging instrument, designed for a mobile unit (20 ft. ISO container), consists of a 32-element array of 15 cm×15 cm×15 cm liquid scintillation detectors (EJ-309) mounted behind a 12×12 pseudorandom coded aperture. The elements of the aperture are composed of 15 cm×15 cm×10 cm blocks of high-density polyethylene (HDPE). The arrangement of the aperture elements produces a shadow pattern on the detector array behind the mask. By measuring of the number of neutron counts per masked and unmasked detector, and with knowledge of the mask pattern, a source image can be deconvolved to obtain a 2-d location. The number of neutrons per detector was obtained by processing the fast signal from each PMT in flash digitizing electronics. Digital pulse shape discrimination (PSD) was performed to filter out the fast-neutron signal from the γ background. The prototype instrument was tested at an indoor facility at the NRL with a 1.8-μCi and 13-μCi 252Cf neutron/γ source at three standoff distances of 9, 15 and 26 m (maximum allowed in the facility) over a 15-min integration time. The imaging and detection capabilities of the instrument were tested by moving the source in half- and one-pixel increments across the image plane. We show a representative sample of the results obtained at one-pixel increments for a standoff distance of 9 m. The 1.8-μCi source was not detected at the 26-m standoff. In order to increase the sensitivity of the instrument, we reduced the fastneutron background by shielding the top, sides and back of the detector array with 10-cm-thick HDPE. This shielding configuration led to a reduction in the background by a factor of 1.7 and thus allowed for the detection and localization of the 1.8 μCi. The detection significance for each source at different standoff distances will be discussed.

  12. Modularized Parallel Neutron Instrument Simulation on the TeraGrid

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Meili; Cobb, John W; Hagen, Mark E

    2007-01-01

    In order to build a bridge between the TeraGrid (TG), a national scale cyberinfrastructure resource, and neutron science, the Neutron Science TeraGrid Gateway (NSTG) is focused on introducing productive HPC usage to the neutron science community, primarily the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). Monte Carlo simulations are used as a powerful tool for instrument design and optimization at SNS. One of the successful efforts of a collaboration team composed of NSTG HPC experts and SNS instrument scientists is the development of a software facility named PSoNI, Parallelizing Simulations of Neutron Instruments. Parallelizing the traditional serialmore » instrument simulation on TeraGrid resources, PSoNI quickly computes full instrument simulation at sufficient statistical levels in instrument de-sign. Upon SNS successful commissioning, to the end of 2007, three out of five commissioned instruments in SNS target station will be available for initial users. Advanced instrument study, proposal feasibility evalua-tion, and experiment planning are on the immediate schedule of SNS, which pose further requirements such as flexibility and high runtime efficiency on fast instrument simulation. PSoNI has been redesigned to meet the new challenges and a preliminary version is developed on TeraGrid. This paper explores the motivation and goals of the new design, and the improved software structure. Further, it describes the realized new fea-tures seen from MPI parallelized McStas running high resolution design simulations of the SEQUOIA and BSS instruments at SNS. A discussion regarding future work, which is targeted to do fast simulation for automated experiment adjustment and comparing models to data in analysis, is also presented.« less

  13. Dynamic Stability Instrumentation System (DSIS). Volume 3; User Manual

    NASA Technical Reports Server (NTRS)

    Daniels, Taumi S.; Boyden, Richmond P.; Dress, David A.; Jordan, Thomas L.

    1996-01-01

    The paper is an operating manual for the Dynamic Stability Instrumentation System in specific NASA Langley wind tunnels. The instrumentation system performs either a synchronous demodulation or a Fast Fourier Transform on dynamic balance strain gage signals, and ultimately computes aerodynamic coefficients. The dynamic balance converts sting motor rotation into pitch or yaw plane or roll axis oscillation, with timing information provided by a shaft encoder. Additional instruments control model attitude and balance temperature and monitor sting vibrations. Other instruments perform self-calibration and diagnostics. Procedures for conducting calibrations and wind-off and wind-on tests are listed.

  14. Instrumentation for Studies of Electron Emission and Charging From Insulators

    NASA Technical Reports Server (NTRS)

    Thomson, C. D.; Zavyalov, V.; Dennison, J. R.

    2004-01-01

    Making measurements of electron emission properties of insulators is difficult since insulators can charge either negatively or positively under charge particle bombardment. In addition, high incident energies or high fluences can result in modification of a material s conductivity, bulk and surface charge profile, structural makeup through bond breaking and defect creation, and emission properties. We discuss here some of the charging difficulties associated with making insulator-yield measurements and review the methods used in previous studies of electron emission from insulators. We present work undertaken by our group to make consistent and accurate measurements of the electron/ion yield properties for numerous thin-film and thick insulator materials using innovative instrumentation and techniques. We also summarize some of the necessary instrumentation developed for this purpose including fast response, low-noise, high-sensitivity ammeters; signal isolation and interface to standard computer data acquisition apparatus using opto-isolation, sample-and-hold, and boxcar integration techniques; computer control, automation and timing using Labview software; a multiple sample carousel; a pulsed, compact, low-energy, charge neutralization electron flood gun; and pulsed visible and UV light neutralization sources. This work is supported through funding from the NASA Space Environments and Effects Program and the NASA Graduate Research Fellowship Program.

  15. Detection of dust impacts by the Voyager planetary radio astronomy experiment

    NASA Technical Reports Server (NTRS)

    Evans, David R.

    1993-01-01

    The Planetary Radio Astronomy (PRA) instrument detected large numbers of dust particles during the Voyager 2 encounter with Neptune. The signatures of these impacts are analyzed in some detail. The major conclusions are described. PRA detects impacts from all over the spacecraft body, not just the PRA antennas. The signatures of individual impacts last substantially longer than was expected from complementary Plasma Wave Subsystem (PWS) data acquired by another Voyager experiment. The signatures of individual impacts demonstrate very rapid fluctuations in signal strength, so fast that the data are limited by the speed of response of the instrument. The PRA detects events at a rate consistently lower than does the Plasma Wave subsystem. Even so, the impact rate is so great near the inbound crossing of the ring plane that no reliable estimate of impact rate can be made for this period. The data are consistent with the presence of electrons accelerated by ions within an expanding plasma cloud from the point of impact. An ancillary conclusion is that the anomalous appearance of data acquired at 900 kHz appears to be due to an error in processing the PRA data prior to their delivery rather than due to overload of the PRA instrument.

  16. CLOUDCLOUD : general-purpose instrument monitoring and data managing software

    NASA Astrophysics Data System (ADS)

    Dias, António; Amorim, António; Tomé, António

    2016-04-01

    An effective experiment is dependent on the ability to store and deliver data and information to all participant parties regardless of their degree of involvement in the specific parts that make the experiment a whole. Having fast, efficient and ubiquitous access to data will increase visibility and discussion, such that the outcome will have already been reviewed several times, strengthening the conclusions. The CLOUD project aims at providing users with a general purpose data acquisition, management and instrument monitoring platform that is fast, easy to use, lightweight and accessible to all participants of an experiment. This work is now implemented in the CLOUD experiment at CERN and will be fully integrated with the experiment as of 2016. Despite being used in an experiment of the scale of CLOUD, this software can also be used in any size of experiment or monitoring station, from single computers to large networks of computers to monitor any sort of instrument output without influencing the individual instrument's DAQ. Instrument data and meta data is stored and accessed via a specially designed database architecture and any type of instrument output is accepted using our continuously growing parsing application. Multiple databases can be used to separate different data taking periods or a single database can be used if for instance an experiment is continuous. A simple web-based application gives the user total control over the monitored instruments and their data, allowing data visualization and download, upload of processed data and the ability to edit existing instruments or add new instruments to the experiment. When in a network, new computers are immediately recognized and added to the system and are able to monitor instruments connected to them. Automatic computer integration is achieved by a locally running python-based parsing agent that communicates with a main server application guaranteeing that all instruments assigned to that computer are monitored with parsing intervals as fast as milliseconds. This software (server+agents+interface+database) comes in easy and ready-to-use packages that can be installed in any operating system, including Android and iOS systems. This software is ideal for use in modular experiments or monitoring stations with large variability in instruments and measuring methods or in large collaborations, where data requires homogenization in order to be effectively transmitted to all involved parties. This work presents the software and provides performance comparison with previously used monitoring systems in the CLOUD experiment at CERN.

  17. Vape Factor Fast Find-Adult (VF3-A): a prototype survey method for recording brand-specific vaping factors in adult populations.

    PubMed

    Ross, Craig S; Zhang, Tancy C; DeJong, William; Siegel, Michael

    2018-03-23

    In population studies, vaping is often treated as a dichotomous exposure (present/absent) without consideration of specific vaping devices and materials being used. A survey instrument is needed to record specific vaping devices and materials. We developed a database of 613 vaping device models and 3196 vaping liquid products, indexed by device brand, device type, liquid brand, liquid name and liquid flavour type. We developed a survey instrument to allow participants to report their vaping device and liquid from the indexed lists. The survey was pilot tested with a convenience sample of 208 adults (≥age 21). We validated the vaping device and liquid responses with a recontact survey. We report the proportion of respondents finding their products, characteristics of people finding their products and survey response times. Devices used most frequently in the past 30 days were electronic cigarettes (33% of respondents), vaping pens (28%) and vaping mods (16%). Fifty-seven per cent used liquids containing nicotine most frequently in the past 30 days, followed by liquids without nicotine (20%) and marijuana or hashish (10%). Most (85%) participants found their vaping device successfully (median 19.7 s) and 74% found their vaping liquid (median 19.8 s). Females and older adults were less likely to find their devices and liquids. Responses were validated for 91% and 76% of devices and e-liquids, respectively. This study demonstrated the feasibility of an internet-based survey instrument to record specific vaping factors for use in studies of vaping and health. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. An advanced real-time digital signal processing system for linear systems emulation, with special emphasis on network and acoustic response characterization

    NASA Astrophysics Data System (ADS)

    Gaydecki, Patrick; Fernandes, Bosco

    2003-11-01

    A fast digital signal processing (DSP) system is described that can perform real-time emulation of a wide variety of linear audio-bandwidth systems and networks, such as reverberant spaces, musical instrument bodies and very high order filter networks. The hardware design is based upon a Motorola DSP56309 operating at 110 million multiplication-accumulations per second and a dual-channel 24 bit codec with a maximum sampling frequency of 192 kHz. High level software has been developed to express complex vector frequency responses as both infinite impulse response (IIR) and finite impulse response (FIR) coefficients, in a form suitable for real-time convolution by the firmware installed in the DSP system memory. An algorithm has also been devised to express IIR filters as equivalent FIR structures, thereby obviating the potential instabilities associated with recursive equations and negating the traditional deficiencies of FIR filters respecting equivalent analogue designs. The speed and dynamic range of the system is such that, when sampling at 48 kHz, the frequency response can be specified to a spectral precision of 22 Hz when sampling at 10 kHz, this resolution increases to 0.9 Hz. Moreover, it is also possible to control the phase of any frequency band with a theoretical precision of 10-5 degrees in all cases. The system has been applied in the study of analogue filter networks, real-time Hilbert transformation, phase-shift systems and musical instrument body emulation, where it is providing valuable new insights into the understanding of psychoacoustic mechanisms.

  19. Decreased insulin response in dairy cows following a four-day fast to induce hepatic lipidosis.

    PubMed

    Oikawa, S; Oetzel, G R

    2006-08-01

    Negative energy balance has been implicated in the development of fatty liver, insulin resistance, and impaired health in dairy cows. A 4-d fasting model previously was reported to increase liver triglycerides more than 2.5-fold. The purpose of the present study was to evaluate insulin response in this fasting model. Nonlactating, nonpregnant Holstein cows were fasted for 4 d (6 cows) or fed continuously as control cows (4 cows). Samples were collected 5 d before fasting, during fasting, and immediately after the 4-d fast, 8 d after the fast, and 16 d after the fast. Fasted cows had greater liver triglyceride content (49.4 vs. 16.2 mg/g, wet-weight basis) at the end of the fasting period compared with control cows. Fasted cows also had increased plasma nonesterified fatty acid (NEFA) concentrations (1.24 vs. 0.21 mmol/L) and increased plasma beta-hydroxybutyrate (BHBA) concentrations at the end of the fasting period. Liver triglyceride, plasma NEFA, and plasma BHBA in fasted cows returned to prefasting concentrations by the end of the experiment. Plasma glucose concentrations were not affected by fasting. Plasma insulin concentrations were decreased (6.3 vs. 14.1 microU/mL) and insulin-stimulated blood glucose reduction was decreased (24.9 vs. 48.6%) in the fasted cows compared with control cows at the end of the fast, indicating reduced insulin response. Insulin response was negatively correlated with plasma NEFA and liver triglycerides. Decreased insulin response may be an important complication of negative energy balance and hepatic lipidosis.

  20. On the impact of GNSS ambiguity resolution: geometry, ionosphere, time and biases

    NASA Astrophysics Data System (ADS)

    Khodabandeh, A.; Teunissen, P. J. G.

    2018-06-01

    Integer ambiguity resolution (IAR) is the key to fast and precise GNSS positioning and navigation. Next to the positioning parameters, however, there are several other types of GNSS parameters that are of importance for a range of different applications like atmospheric sounding, instrumental calibrations or time transfer. As some of these parameters may still require pseudo-range data for their estimation, their response to IAR may differ significantly. To infer the impact of ambiguity resolution on the parameters, we show how the ambiguity-resolved double-differenced phase data propagate into the GNSS parameter solutions. For that purpose, we introduce a canonical decomposition of the GNSS network model that, through its decoupled and decorrelated nature, provides direct insight into which parameters, or functions thereof, gain from IAR and which do not. Next to this qualitative analysis, we present for the GNSS estimable parameters of geometry, ionosphere, timing and instrumental biases closed-form expressions of their IAR precision gains together with supporting numerical examples.

  1. Radiometric and spectral stray light correction for the portable remote imaging spectrometer (PRISM) coastal ocean sensor

    NASA Astrophysics Data System (ADS)

    Haag, Justin M.; Van Gorp, Byron E.; Mouroulis, Pantazis; Thompson, David R.

    2017-09-01

    The airborne Portable Remote Imaging Spectrometer (PRISM) instrument is based on a fast (F/1.8) Dyson spectrometer operating at 350-1050 nm and a two-mirror telescope combined with a Teledyne HyViSI 6604A detector array. Raw PRISM data contain electronic and optical artifacts that must be removed prior to radiometric calibration. We provide an overview of the process transforming raw digital numbers to calibrated radiance values. Electronic panel artifacts are first corrected using empirical relationships developed from laboratory data. The instrument spectral response functions (SRF) are reconstructed using a measurement-based optimization technique. Removal of SRF effects from the data improves retrieval of true spectra, particularly in the typically low-signal near-ultraviolet and near-infrared regions. As a final step, radiometric calibration is performed using corrected measurements of an object of known radiance. Implementation of the complete calibration procedure maximizes data quality in preparation for subsequent processing steps, such as atmospheric removal and spectral signature classification.

  2. On the impact of GNSS ambiguity resolution: geometry, ionosphere, time and biases

    NASA Astrophysics Data System (ADS)

    Khodabandeh, A.; Teunissen, P. J. G.

    2017-11-01

    Integer ambiguity resolution (IAR) is the key to fast and precise GNSS positioning and navigation. Next to the positioning parameters, however, there are several other types of GNSS parameters that are of importance for a range of different applications like atmospheric sounding, instrumental calibrations or time transfer. As some of these parameters may still require pseudo-range data for their estimation, their response to IAR may differ significantly. To infer the impact of ambiguity resolution on the parameters, we show how the ambiguity-resolved double-differenced phase data propagate into the GNSS parameter solutions. For that purpose, we introduce a canonical decomposition of the GNSS network model that, through its decoupled and decorrelated nature, provides direct insight into which parameters, or functions thereof, gain from IAR and which do not. Next to this qualitative analysis, we present for the GNSS estimable parameters of geometry, ionosphere, timing and instrumental biases closed-form expressions of their IAR precision gains together with supporting numerical examples.

  3. The Role of APEX as a Pathfinder for AtLAST

    NASA Astrophysics Data System (ADS)

    Wyrowski, Friedrich

    2018-01-01

    Now more than 12 years in operation, the Atacama Pathfinder Experiment (APEX) 12 m submillimeter telescope has significantly contributed to a wide variety of submillimeter astronomy science areas, ranging from the discoveries of new molecules to large and deep imaging of the submillimeter sky. While ALMA operation is in full swing, APEX is strengthening its role not only as pathfinder for studying large source samples and spatial scales to prepare detailed high angular resolution ALMA follow ups, but also as fast response instruments to complement new results from ALMA. Furthermore, APEX ensures southern hemisphere access for submillimeter projects complementing archival Herschel research as well as new SOFIA science. With new broadband and multipixel receivers as well as large cameras for wide-field continuum imaging, APEX will pave the way towards the science envisioned with ATLAST. In this contribution, the current status and ongoing upgrades of APEX will be discussed, with an emphasis on the importance of continuous cutting edge science and state-of-the-art instrumentation that will bridge the gap towards ATLAST.

  4. A Ringdown Breath Analyzer for Diabetes Monitoring: Breath Acetone in Diabetic Patients.

    NASA Astrophysics Data System (ADS)

    Wang, Chuji; Mbi, Armstrong; Shepherd, Mark

    2008-03-01

    It is highly desirable for millions of diabetic patients to have a non-blood, non-invasive, point-of-care device for monitoring daily blood glucose (BG) levels and the adequacy of diabetic treatment and control. Cavity ringdown spectroscopy, due to its unique capability of high sensitivity, fast-response, and relatively low cost for instrumentation, has the potential for medical application through non-invasive analysis of breath biomarkers. We report the first ringdown acetone breath analyzer for clinic testing with diabetic outpatients. The instrument was set in a clinic center and 34 outpatients (24 T1D and 10 T2D) were tested during a four-day period. 10 T1D subjects and 15 nondiabetic persons were tested in our laboratory. Three juvenile-onset T1D subjects were selected for a 24-hr monitoring on the variations of breath acetone and simultaneous BG level. In this talk, we present our research findings including the correlations of breath acetone with BG level and A1C.

  5. Mapping Viscoelastic and Plastic Properties of Polymers and Polymer-Nanotube Composites using Instrumented Indentation

    PubMed Central

    Gayle, Andrew J.; Cook, Robert F.

    2016-01-01

    An instrumented indentation method is developed for generating maps of time-dependent viscoelastic and time-independent plastic properties of polymeric materials. The method is based on a pyramidal indentation model consisting of two quadratic viscoelastic Kelvin-like elements and a quadratic plastic element in series. Closed-form solutions for indentation displacement under constant load and constant loading-rate are developed and used to determine and validate material properties. Model parameters are determined by point measurements on common monolithic polymers. Mapping is demonstrated on an epoxy-ceramic interface and on two composite materials consisting of epoxy matrices containing multi-wall carbon nanotubes. A fast viscoelastic deformation process in the epoxy was unaffected by the inclusion of the nanotubes, whereas a slow viscoelastic process was significantly impeded, as was the plastic deformation. Mapping revealed considerable spatial heterogeneity in the slow viscoelastic and plastic responses in the composites, particularly in the material with a greater fraction of nanotubes. PMID:27563168

  6. Neutron scatter camera

    DOEpatents

    Mascarenhas, Nicholas; Marleau, Peter; Brennan, James S.; Krenz, Kevin D.

    2010-06-22

    An instrument that will directly image the fast fission neutrons from a special nuclear material source has been described. This instrument can improve the signal to background compared to non imaging neutron detection techniques by a factor given by ratio of the angular resolution window to 4.pi.. In addition to being a neutron imager, this instrument will also be an excellent neutron spectrometer, and will be able to differentiate between different types of neutron sources (e.g. fission, alpha-n, cosmic ray, and D-D or D-T fusion). Moreover, the instrument is able to pinpoint the source location.

  7. Science Enabling ASICs and FEEs for the JUICE and JEO Missions

    NASA Technical Reports Server (NTRS)

    Paschalidis, Nicholas; Sittler, Ed; Cooper, John; Christian, Eric; Moore, Tom

    2011-01-01

    A family of science enabling radiation hard Application Specific Integrated Circuits (ASICs), Front End Electronics (FEEs) and Event Processing Systems, with flight heritage on many NASA missions, is presented. These technologies play an important role in the miniaturization of instruments -and spacecraft systems- at the same time increasing performance and reducing power. The technologies target time of flight, position sensing, and energy measurements as well as standard housekeeping and telemetry functions for particle and fields instruments, but find applications in other instrument categories too. More specifically the technologies include: the TOF chip, 1D and 2D Delay Lines with MCP detectors, for high precision fast and low power time of flight and position sensing; the Energy chip for multichannel SSD readout with time over threshold and standard voltage read out for TDC and ADC digitization; Fast multi channel read out chip with commandable thresholds; the TRIO chip for multiplexed ADC and housekeeping etc. It should be mentioned that the ASICs include basic trigger capabilities to enable random event processing in a heavy background of penetrators and UV foreground. Typical instruments include time of flight versus energy and look angle particle analyzers such as: plasma composition, energetic particle, neutral atom imaging as well as fast plasma and deltaE/E ion/electron telescopes. Flight missions include: Cassini/LEMMS, IMAGE/HENA, MESSENGER/EPPS/MLA/X-ray/MLA, STEREO, PLUTO-NH/PEPSSI/LORI, IBEX-Lo, JUNO/JEDI, RBSP/RBSPICE, MMS/HPCA/EPD, SO/SIS. Given the proven capability on heavy radiation missions such as JUNO, MMS and RBSB, as well diverse long duration missions such as MESSENGER, PLUTO and Cassini, it is expected that these technologies will play an important role in the particle and fields (at least) instruments on the upcoming JUICE and JEO missions.

  8. MetaSensing's FastGBSAR: ground based radar for deformation monitoring

    NASA Astrophysics Data System (ADS)

    Rödelsperger, Sabine; Meta, Adriano

    2014-10-01

    The continuous monitoring of ground deformation and structural movement has become an important task in engineering. MetaSensing introduces a novel sensor system, the Fast Ground Based Synthetic Aperture Radar (FastGBSAR), based on innovative technologies that have already been successfully applied to airborne SAR applications. The FastGBSAR allows the remote sensing of deformations of a slope or infrastructure from up to a distance of 4 km. The FastGBSAR can be setup in two different configurations: in Real Aperture Radar (RAR) mode it is capable of accurately measuring displacements along a linear range profile, ideal for monitoring vibrations of structures like bridges and towers (displacement accuracy up to 0.01 mm). Modal parameters can be determined within half an hour. Alternatively, in Synthetic Aperture Radar (SAR) configuration it produces two-dimensional displacement images with an acquisition time of less than 5 seconds, ideal for monitoring areal structures like dams, landslides and open pit mines (displacement accuracy up to 0.1 mm). The MetaSensing FastGBSAR is the first ground based SAR instrument on the market able to produce two-dimensional deformation maps with this high acquisition rate. By that, deformation time series with a high temporal and spatial resolution can be generated, giving detailed information useful to determine the deformation mechanisms involved and eventually to predict an incoming failure. The system is fully portable and can be quickly installed on bedrock or a basement. The data acquisition and processing can be fully automated leading to a low effort in instrument operation and maintenance. Due to the short acquisition time of FastGBSAR, the coherence between two acquisitions is very high and the phase unwrapping is simplified enormously. This yields a high density of resolution cells with good quality and high reliability of the acquired deformations. The deformation maps can directly be used as input into an Early Warning system, to determine the state and danger of a slope or structure. In this paper, the technical principles of the instrument are described and case studies of different monitoring tasks are presented.

  9. Effects of Style, Tempo, and Performing Medium on Children's Music Preference.

    ERIC Educational Resources Information Center

    LeBlanc, Albert

    1981-01-01

    Fifth-graders listened to a tape incorporating fast and slow vocal and instrumental excerpts within the generic styles of rock/pop, country, older jazz, newer jazz, art music, and band music. A preference hierarchy emerged favoring the popular styles. Across pooled styles, faster tempos and instrumentals were slightly preferred. (Author/SJL)

  10. Evaluation of four fast-response flow measurement devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gero, A.J.; Suppers, K.L.; Tomb, T.F.

    1988-01-01

    The Federal Mine Safety and Health Act of 1977 requires that sampling of dust in coal mine environments be conducted with an approved sampler operating at a flow rate of 2.0 liters of air per minute or at such other flow rate as prescribed by the Secretaries of Labor and of Health and Human Services. Standard procedures for calibration of these samplers within the Mine Safety and Health Administration utilize either a 3.0 liter capacity wet test meter or a 1.0 liter soap film calibrator. Several new flow calibrating devices have become commercially available. This paper describes an evaluation conductedmore » on four such devices: the Mast Model 823-2 bubble flowmeter, the Buck Calibrator, the Kurz Model 541S mass flowmeter and the Kurz Pocket Calibrator. The precision of a series of measurements made with each instrument was compared to the precision of a series of measurements made with the wet test meter. The comparison showed that the variability of calibration measurements obtained with the fast response flow calibrators was between 1.5 and 4.5 times larger than that obtained with the WTM; however, with all of the calibration devices evaluated, three repetitive measurements were sufficient to obtain a precision of {plus minus}0.1 liters per minute. 4 refs., 2 figs., 1 tab.« less

  11. Constructing a "Fast Protocol" for Middle School Beginner Violin Classes in Japan

    ERIC Educational Resources Information Center

    Akutsu, Taichi

    2018-01-01

    This study aimed to investigate the process of constructing a "fast-protocol" for violin instruction. Since learning string instruments has not been common, and because there are limited hours for music in Japanese schools, the author, a violinist, collaborated with the general music teacher at a middle school in the Tokyo metropolitan…

  12. Nuclear instrumentation in VENUS-F

    NASA Astrophysics Data System (ADS)

    Wagemans, J.; Borms, L.; Kochetkov, A.; Krása, A.; Van Grieken, C.; Vittiglio, G.

    2018-01-01

    VENUS-F is a fast zero power reactor with 30 wt% U fuel and Pb/Bi as a coolant simulator. Depending on the experimental configuration, various neutron spectra (fast, epithermal, and thermal islands) are present. This paper gives a review of the nuclear instrumentation that is applied for reactor control and in a large variety of physics experiments. Activation foils and fission chambers are used to measure spatial neutron flux profiles, spectrum indices, reactivity effects (with positive period and compensation method or the MSM method) and kinetic parameters (with the Rossi-alpha method). Fission chamber calibrations are performed in the standard irradiation fields of the BR1 reactor (prompt fission neutron spectrum and Maxwellian thermal neutron spectrum).

  13. Intercomparison of fast response commercial gas analysers for nitrous oxide flux measurements under field conditions

    NASA Astrophysics Data System (ADS)

    Rannik, Ü.; Haapanala, S.; Shurpali, N. J.; Mammarella, I.; Lind, S.; Hyvönen, N.; Peltola, O.; Zahniser, M.; Martikainen, P. J.; Vesala, T.

    2014-08-01

    Four gas analysers capable of measuring nitrous oxide (N2O) concentration at a response time necessary for eddy covariance flux measurements were operated from spring till winter 2011 over a field cultivated with reed canary grass (RCG, Phalaris arundinaceae, L.), a perennial bioenergy crop in Eastern Finland. The instruments were TGA100A (Campbell Scientific Inc.), CW-TILDAS-CS (Aerodyne Research Inc.), N2O/CO-23d (Los Gatos Research Inc.) and QC-TILDAS-76-CS (Aerodyne Research Inc.). The period with high emission, lasting for about two weeks after fertilization in late May, was characterised by an up to two orders of magnitude higher emission, whereas during the rest of the campaign the N2O fluxes were small, from 0.1 to 1 nmol m-2 s-1. Two instruments, CW-TILDAS-CS and N2O/CO-23d, determined the N2O exchange with minor systematic difference throughout the campaign, when operated simultaneously. TGA100A produced cumulatively highest N2O estimates (with 29% higher value during the period when all instruments were operational). QC-TILDAS-76-CS obtained 36% lower fluxes than CW-TILDAS-CS during the first period, including the emission episode, whereas the correspondence with other instruments during the rest of the campaign was good. The reason for these episodic higher and lower estimates by the two instruments is not currently known, suggesting further need for detailed evaluation of instrument performance under field conditions with emphasis on stability, calibration and, in particular, simultaneous accurate determination of water vapour concentration due to its large impact on small N2O fluxes through spectroscopic and dilution corrections. The instrument CW-TILDAS-CS was characterised by the lowest noise level (std around 0.12 ppb at 10 Hz sampling rate), as compared to N2O/CO-23d and QC-TILDAS-76-CS (around 0.50 ppb) and TGA100A (around 2 ppb). Both instruments based on Continuous-Wave Quantum Cascade Lasers, CW-TILDAS-CS and N2O/CO-23d, were able to determine the same sample of low N2O fluxes with high mutual coefficient of determination at 30 min averaging level and with minor systematic difference over the observation period of several months.

  14. Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jacobsen, A. S., E-mail: Ajsen@fysik.dtu.dk; Salewski, M.; Korsholm, S. B.

    2014-11-15

    The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR.

  15. Kinetic studies of the yeast His-Asp phosphorelay signaling pathway

    PubMed Central

    Kaserer, Alla O.; Andi, Babak; Cook, Paul F.; West, Ann H.

    2010-01-01

    For both prokaryotic and eukaryotic His-Asp phosphorelay signaling pathways, the rates of protein phosphorylation and dephosphorylation determine the stimulus-to-response time frame. Thus, kinetic studies of phosphoryl group transfer between signaling partners are important for gaining a full understanding of how the system is regulated. In many cases, the phosphotransfer reactions are too fast for rates to be determined by manual experimentation. Rapid quench flow techniques thus provide a powerful method for studying rapid reactions that occur in the millisecond time frame. In this chapter, we describe experimental design and procedures for kinetic characterization of the yeast SLN1-YPD1-SSK1 osmoregulatory phosphorelay system using a rapid quench flow kinetic instrument. PMID:20946842

  16. Gait characteristics, balance performance and falls in ambulant adults with cerebral palsy: An observational study.

    PubMed

    Morgan, P; Murphy, A; Opheim, A; McGinley, J

    2016-07-01

    The relationship between spatiotemporal gait parameters, balance performance and falls history was investigated in ambulant adults with cerebral palsy (CP). Participants completed a single assessment of gait using an instrumented walkway at preferred and fast speeds, balance testing (Balance Evaluation Systems Test; BESTest), and reported falls history. Seventeen ambulatory adults with CP, mean age 37 years, participated. Gait speed was typically slow at both preferred and fast speeds (mean 0.97 and 1.21m/s, respectively), with short stride length and high cadence relative to speed. There was a significant, large positive relationship between preferred gait speed and BESTest total score (ρ=0.573; p<0.05) and fast gait speed and BESTest total score (ρ=0.647, p<0.01). The stride lengths of fallers at both preferred and fast speeds differed significantly from non-fallers (p=0.032 and p=0.025, respectively), with those with a prior history of falls taking shorter strides. Faster gait speed was associated with better performance on tests of anticipatory and postural response components of the BESTest, suggesting potential therapeutic training targets to address either gait speed or balance performance. Future exploration of the implications of slow walking speed and reduced stride length on falls and community engagement, and the potential prognostic value of stride length on identifying falls risk is recommended. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  17. Validity and Reliability of the Italian Version of the Functioning Assessment Short Test (FAST) in Bipolar Disorder

    PubMed Central

    Moro, Maria Francesca; Colom, Francesc; Floris, Francesca; Pintus, Elisa; Pintus, Mirra; Contini, Francesca; Carta, Mauro Giovanni

    2012-01-01

    Background: Functioning Assessment Short Test (FAST) is a brief instrument designed to assess the main functioning problems experienced by psychiatric patients, specifically bipolar patients. It includes 24 items assessing impairment or disability in six domains of functioning: autonomy, occupational functioning, cognitive functioning, financial issues, interpersonal relationships and leisure time. The aim of this study is to measure the validity and reliability of the Italian version of this instrument. Methods: Twenty-four patients with DSM-IV TR bipolar disorder and 20 healthy controls were recruited and evaluated in three private clinics in Cagliari (Sardinia, Italy). The psychometric properties of FAST (feasibility, internal consistency, concurrent validity, discriminant validity (patients vs controls and eutimic patients vs manic and depressed), and test-retest reliability were analyzed. Results: The internal consistency obtained was very high with a Cronbach's alpha of 0.955. A highly significant negative correlation with GAF was obtained (r = -0.9; p < 0.001) pointing to a reasonable degree of concurrent validity. FAST show a good test-retest reliability between two independent evaluation differing of one week (mean K =0.73). The total FAST scores were lower in controls as compared with Bipolar Patients and in Euthimic patients compared with Depressed or Manic. Conclusion: The Italian version of the FAST showed similar psychometrics properties as far as regard internal consistency and discriminant validity of the original version and show a good test retest reliability measure by means of K statistics. PMID:22905035

  18. Relationship between wind, waves and radar backscatter

    NASA Technical Reports Server (NTRS)

    Katsaros, Kristina B.; Ataktuerk, Serhad S.

    1991-01-01

    The aim of the research was to investigate the relationship between wind, waves, and radar backscatter from water surface. To this end, three field experiments with periods of 2 to 4 weeks were carried out during summer months in 1988, 1989 and 1990. For these periods, the University of Washington group provided (1) environmental parameters such as wind speed, wind stress, and atmospheric stratification through measurements of surface fluxes (of momentum, sensible heat and latent heat) and of air and water temperatures; and (2) wave height spectra including both the dominant waves and the short gravity-capillary waves. Surface flux measurements were performed by using our well tested instruments: a K-Gill twin propeller-vane anemometer and a fast response thermocouple psychrometer. Wave heights were measured by a resistance wire wave gauge. The University of Kansas group was responsible for the operation of the microwave radars.

  19. XIMPOL: a new x-ray polarimetry observation-simulation and analysis framework

    NASA Astrophysics Data System (ADS)

    Omodei, Nicola; Baldini, Luca; Pesce-Rollins, Melissa; di Lalla, Niccolò

    2017-08-01

    We present a new simulation framework, XIMPOL, based on the python programming language and the Scipy stack, specifically developed for X-ray polarimetric applications. XIMPOL is not tied to any specific mission or instrument design and is meant to produce fast and yet realistic observation-simulations, given as basic inputs: (i) an arbitrary source model including morphological, temporal, spectral and polarimetric information, and (ii) the response functions of the detector under study, i.e., the effective area, the energy dispersion, the point-spread function and the modulation factor. The format of the response files is OGIP compliant, and the framework has the capability of producing output files that can be directly fed into the standard visualization and analysis tools used by the X-ray community, including XSPEC which make it a useful tool not only for simulating physical systems, but also to develop and test end-to-end analysis chains.

  20. Response deprivation, reinforcement, and economics

    PubMed Central

    Allison, James

    1993-01-01

    Reinforcement of an instrumental response results not from a special kind of response consequence known as a reinforcer, but from a special kind of schedule known as a response-deprivation schedule. Under the requirements of a response-deprivation schedule, the baseline rate of the instrumental response permits less than the baseline rate of the contingent response. Because reinforcement occurs only if the schedule deprives the organism of the contingent response, reinforcement cannot result from any intrinsic property of the contingent response or any property relative to the instrumental response. Two typical effects of response-deprivation schedules—facilitation of the instrumental response and suppression of the contingent response—are discussed in terms of economic concepts and models of instrumental performance. It is suggested that response deprivation makes the contingent response function as an economic good, the instrumental response as currency. PMID:16812695

  1. Balloon flight test of a Compton telescope based on scintillators with silicon photomultiplier readouts

    NASA Astrophysics Data System (ADS)

    Bloser, P. F.; Legere, J. S.; Bancroft, C. M.; Ryan, J. M.; McConnell, M. L.

    2016-03-01

    We present the results of the first high-altitude balloon flight test of a concept for an advanced Compton telescope making use of modern scintillator materials with silicon photomultiplier (SiPM) readouts. There is a need in the fields of high-energy astronomy and solar physics for new medium-energy gamma-ray ( 0.4-10 MeV) detectors capable of making sensitive observations of both line and continuum sources over a wide dynamic range. A fast scintillator-based Compton telescope with SiPM readouts is a promising solution to this instrumentation challenge, since the fast response of the scintillators permits both the rejection of background via time-of-flight (ToF) discrimination and the ability to operate at high count rates. The Solar Compton Telescope (SolCompT) prototype presented here was designed to demonstrate stable performance of this technology under balloon-flight conditions. The SolCompT instrument was a simple two-element Compton telescope, consisting of an approximately one-inch cylindrical stilbene crystal for a scattering detector and a one-inch cubic LaBr3:Ce crystal for a calorimeter detector. Both scintillator detectors were read out by 2×2 arrays of Hamamatsu S11828-3344 MPPC devices. Custom front-end electronics provided optimum signal rise time and linearity, and custom power supplies automatically adjusted the SiPM bias voltage to compensate for temperature-induced gain variations. A tagged calibration source, consisting of 240 nCi of 60Co embedded in plastic scintillator, was placed in the field of view and provided a known source of gamma rays to measure in flight. The SolCompT balloon payload was launched on 24 August 2014 from Fort Sumner, NM, and spent 3.75 h at a float altitude of 123,000 ft. The instrument performed well throughout the flight. After correcting for small ( 10%) residual gain variations, we measured an in-flight ToF resolution of 760 ps (FWHM). Advanced scintillators with SiPM readouts continue to show great promise for future gamma-ray instruments.

  2. Synopsis of a computer program designed to interface a personal computer with the fast data acquisition system of a time-of-flight mass spectrometer

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

    Briefly described are the essential features of a computer program designed to interface a personal computer with the fast, digital data acquisition system of a time-of-flight mass spectrometer. The instrumentation was developed to provide a time-resolved analysis of individual vapor pulses produced by the incidence of a pulsed laser beam on an ablative material. The high repetition rate spectrometer coupled to a fast transient recorder captures complete mass spectra every 20 to 35 microsecs, thereby providing the time resolution needed for the study of this sort of transient event. The program enables the computer to record the large amount of data generated by the system in short time intervals, and it provides the operator the immediate option of presenting the spectral data in several different formats. Furthermore, the system does this with a high degree of automation, including the tasks of mass labeling the spectra and logging pertinent instrumental parameters.

  3. Solar Polar ORbit Telescope (SPORT): A Potential Space Weather Mission of China

    NASA Astrophysics Data System (ADS)

    Liu, Y. D.; Xiong, M.; Wu, J.; Liu, H.; Zheng, J.; Li, B.; Zhang, C.; Sun, W.

    2013-12-01

    We describe a spacecraft mission, named Solar Polar ORbit Telescope (SPORT), which is currently under a scientific and engineering background study in China. SPORT was originally proposed in 2004 by the National Space Science Center, Chinese Academy of Sciences. It will carry a suite of remote-sensing and in-situ instruments to observe coronal mass ejections (CMEs), solar high-latitude magnetism, and the fast solar wind from a polar orbit around the Sun. It is intended to be the first mission that carries remote-sensing instruments from a high-latitude orbit around the Sun, the first mission that could image interplanetary CMEs at radio wavelengths from space, and the first mission that could measure solar high-latitude magnetism leading to eruptions and the fast solar wind. The first extended view of the polar region of the Sun and the ecliptic plane enabled by SPORT will provide a unique opportunity to study CME propagation through the inner heliosphere and solar high-latitude magnetism giving rise to eruptions and the fast solar wind.

  4. Dual Raman-Brillouin spectroscopic investigation of plant stress response and development

    NASA Astrophysics Data System (ADS)

    Coker, Zachary; Troyanova-Wood, Maria; Marble, Kassie; Yakovlev, Vladislav

    2018-03-01

    Raman and Brillouin spectroscopy are powerful tools for non-invasive and non-destructive investigations of material chemical and mechanical properties. In this study, we use a newly developed custom-built dual Raman-Brillouin microspectroscopy instrument to build on previous works studying in-vivo stress response of live plants using only a Raman spectroscopy system. This dual Raman-Brillouin spectroscopy system is capable of fast simultaneous spectra acquisition from single-point locations. Shifts and changes in a samples Brillouin spectrum indicate a change in the physical characteristics of the sample, namely mechano-elasticity; in measuring this change, we can establish a relationship between the mechanical properties of a sample and known stress response agents, such as reactive oxygen species and other chemical constituents as indicated by peaks in the Raman spectra of the same acquisition point. Simultaneous application of these spectroscopic techniques offers great promise for future development and applications in agricultural and biological studies and can help to improve our understanding of mechanochemical changes of plants and other biological samples in response to environmental and chemically induced stresses at microscopic or cellular level.

  5. Advances in the RXTE Proportional Counter Array Calibration: Nearing the Statistical Limit

    NASA Technical Reports Server (NTRS)

    Shaposhnikov, Nikolai; Jahoda, Keith; Markwardt, Craig; Swank, Jean; Strohmayer, Tod

    2012-01-01

    During its 16 years of service Rossi X-ray Timing Explorer (RXTE) mission has provided an extensive archive of data, which will serve as a primary source of high cadence observation of variable X-ray sources for fast timing studies. It is, therefore, very important to have the most reliable calibration of RXTE instruments. The Proportional Counter Array (PCA) is the primary instrument on-board RXTE which provides data in 2-50 keY with higher than millisecond time resolution in up to 256 energy channels. In 2009 RXTE team revised the response residual minimization method used to derive the parameters of the PCA physical model. The procedure is now based on the residual minimization between the model spectrum for Crab nebula emission and a calibration data set consisting of a number of spectra from the Crab and the on-board Am241 calibration source, uniformly covering a whole RXTE span. The new method led to a much more effective model convergence and allowed for better understanding of the behavior of the PCA energy-to-channel relationship. It greatly improved the response matrix performance. We describe the new version of the RXTE/PCA response generator PCARMF vll.7 along with the corresponding energy-to-channel conversion table (version e05v04) and their difference from the previous releases of PCA calibration. The new PCA response adequately represents the spectrum of the calibration sources and successfully predicts the energy of the narrow iron emission line in Cas-A throughout the RXTE mission.

  6. 77 FR 65541 - Agency Information Collection Activities; Submission to the Office of Management and Budget for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-29

    ...; Submission to the Office of Management and Budget for Review and Approval; Comment Request; Fast Response... in response to this notice will be considered public records. Title of Collection: Fast Response... (QRIS) (OMB 1850-0733) to conduct data collection for the Fast Response Survey System (FRSS) survey 105...

  7. Comparison of on-line and off-line methods to quantify reactive oxygen species (ROS) in atmospheric aerosols

    NASA Astrophysics Data System (ADS)

    Fuller, S. J.; Wragg, F. P. H.; Nutter, J.; Kalberer, M.

    2014-08-01

    Atmospheric aerosol particle concentrations have been linked with a wide range of pulmonary and cardio-vascular diseases but the particle properties responsible for these negative health effects are largely unknown. It is often speculated that reactive oxygen species (ROS) present in atmospheric particles lead to oxidative stress in, and ultimately disease of, the human lung. The quantification of ROS is highly challenging because some ROS components such as radicals are highly reactive and therefore short-lived. Thus, fast analysis methods are likely advantageous over methods with a long delay between aerosol sampling and ROS analysis. We present for the first time a detailed comparison of conventional off-line and fast on-line methods to quantify ROS in organic aerosols. For this comparison a new and fast on-line instrument was built and characterized to quantify ROS in aerosol particles with high sensitivity and a limit of detection of 4 nmol H2O2 equivalents per m3 air. ROS concentrations are measured with a time resolution of approximately 15 min, which allows the tracking of fast changing atmospheric conditions. The comparison of the off-line and on-line method shows that, in oxidized organic model aerosol particles, the majority of ROS have a very short lifetime of a few minutes whereas a small fraction is stable for a day or longer. This indicates that off-line techniques, where there is often a delay of hours to days between particle collection and ROS analysis, may severely underestimate true ROS concentrations and that fast on-line techniques are necessary for a reliable ROS quantification in atmospheric aerosol particles and a meaningful correlation with health outcomes.

  8. Enhanced Analysis Techniques for an Imaging Neutron and Gamma Ray Spectrometer

    NASA Astrophysics Data System (ADS)

    Madden, Amanda C.

    The presence of gamma rays and neutrons is a strong indicator of the presence of Special Nuclear Material (SNM). The imaging Neutron and gamma ray SPECTrometer (NSPECT) developed by the University of New Hampshire and Michigan Aerospace corporation detects the fast neutrons and prompt gamma rays from fissile material, and the gamma rays from radioactive material. The instrument operates as a double scatter device, requiring a neutron or a gamma ray to interact twice in the instrument. While this detection requirement decreases the efficiency of the instrument, it offers superior background rejection and the ability to measure the energy and momentum of the incident particle. These measurements create energy spectra and images of the emitting source for source identification and localization. The dual species instrument provides superior detection than a single species alone. In realistic detection scenarios, few particles are detected from a potential threat due to source shielding, detection at a distance, high background, and weak sources. This contributes to a small signal to noise ratio, and threat detection becomes difficult. To address these difficulties, several enhanced data analysis tools were developed. A Receiver Operating Characteristic Curve (ROC) helps set instrumental alarm thresholds as well as to identify the presence of a source. Analysis of a dual-species ROC curve provides superior detection capabilities. Bayesian analysis helps to detect and identify the presence of a source through model comparisons, and helps create a background corrected count spectra for enhanced spectroscopy. Development of an instrument response using simulations and numerical analyses will help perform spectra and image deconvolution. This thesis will outline the principles of operation of the NSPECT instrument using the double scatter technology, traditional analysis techniques, and enhanced analysis techniques as applied to data from the NSPECT instrument, and an outline of how these techniques can be used to superior detection of radioactive and fissile materials.

  9. Instrumentation for fast-scan cyclic voltammetry combined with electrophysiology for behavioral experiments in freely moving animals

    NASA Astrophysics Data System (ADS)

    Takmakov, Pavel; McKinney, Collin J.; Carelli, Regina M.; Wightman, R. Mark

    2011-07-01

    Fast-scan cyclic voltammetry is a unique technique for sampling dopamine concentration in the brain of rodents in vivo in real time. The combination of in vivo voltammetry with single-unit electrophysiological recording from the same microelectrode has proved to be useful in studying the relationship between animal behavior, dopamine release and unit activity. The instrumentation for these experiments described here has two unique features. First, a 2-electrode arrangement implemented for voltammetric measurements with the grounded reference electrode allows compatibility with electrophysiological measurements, iontophoresis, and multielectrode measurements. Second, we use miniaturized electronic components in the design of a small headstage that can be fixed on the rat's head and used in freely moving animals.

  10. Error analysis for fast scintillator-based inertial confinement fusion burn history measurements

    NASA Astrophysics Data System (ADS)

    Lerche, R. A.; Ognibene, T. J.

    1999-01-01

    Plastic scintillator material acts as a neutron-to-light converter in instruments that make inertial confinement fusion burn history measurements. Light output for a detected neutron in current instruments has a fast rise time (<20 ps) and a relatively long decay constant (1.2 ns). For a burst of neutrons whose duration is much shorter than the decay constant, instantaneous light output is approximately proportional to the integral of the neutron interaction rate with the scintillator material. Burn history is obtained by deconvolving the exponential decay from the recorded signal. The error in estimating signal amplitude for these integral measurements is calculated and compared with a direct measurement in which light output is linearly proportional to the interaction rate.

  11. Instrumentation for fast-scan cyclic voltammetry combined with electrophysiology for behavioral experiments in freely moving animals

    PubMed Central

    Takmakov, Pavel; McKinney, Collin J.; Carelli, Regina M.; Wightman, R. Mark

    2011-01-01

    Fast-scan cyclic voltammetry is a unique technique for sampling dopamine concentration in the brain of rodents in vivo in real time. The combination of in vivo voltammetry with single-unit electrophysiological recording from the same microelectrode has proved to be useful in studying the relationship between animal behavior, dopamine release and unit activity. The instrumentation for these experiments described here has two unique features. First, a 2-electrode arrangement implemented for voltammetric measurements with the grounded reference electrode allows compatibility with electrophysiological measurements, iontophoresis, and multielectrode measurements. Second, we use miniaturized electronic components in the design of a small headstage that can be fixed on the rat's head and used in freely moving animals. PMID:21806203

  12. Design and development of a fast ion mass spectrometer

    NASA Technical Reports Server (NTRS)

    Burch, J. L.

    1983-01-01

    Two Fast Ion Mass Spectrometers (FIMS A and FIMS B) were developed. The design, development, construction, calibration, integration, and flight of these instruments, along with early results from the data analysis efforts are summarized. A medium energy ion mass spectrometer that covers mass velocity space with significantly higher time resolution, improved mass resolution, (particularly for heavier ions), and wider energy range than existing instruments had achieved was completed. The initial design consisted of a dual channel cylindrical electrostatic analyzer followed by a dual channel cylindrical velocity filter. The gain versus count rate characteristics of the high current channel electron multipliers (CEM's), which were chosen for ion detection, revealed a systematic behavior that can be used as a criterion for selection of CEM's for long counting lifetimes.

  13. Fast Plasma Investigation for Magnetospheric Multiscale

    NASA Technical Reports Server (NTRS)

    Pollock, C.; Moore, T.; Coffey, V.; Dorelli J.; Giles, B.; Adrian, M.; Chandler, M.; Duncan, C.; Figueroa-Vinas, A.; Garcia, K.; hide

    2016-01-01

    The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics. This increased resolution has been accomplished by placing four dual 180-degree top hat spectrometers for electrons and four dual 180-degree top hat spectrometers for ions around the periphery of each of four MMS spacecraft. Using electrostatic field-of-view deflection, the eight spectrometers for each species together provide 4pi-sr-field-of-view with, at worst, 11.25-degree sample spacing. Energy/charge sampling is provided by swept electrostatic energy/charge selection over the range from 10 eVq to 30000 eVq. The eight dual spectrometers on each spacecraft are controlled and interrogated by a single block redundant Instrument Data Processing Unit, which in turn interfaces to the observatory's Instrument Suite Central Instrument Data processor. This paper described the design of FPI, its ground and in-flight calibration, its operational concept, and its data products.

  14. Electronic Implementation of Integrated End-of-life Care: A Local Approach

    PubMed Central

    Schlieper, Daniel; Altreuther, Christiane; Schallenburger, Manuela; Neukirchen, Martin; Schmitz, Andrea

    2017-01-01

    Introduction: The Liverpool Care Pathway for the Dying Patient is an instrument to deliver integrated care for patients in their last hours of life. Originally a paper-based system, this study investigates the feasibility of an electronic version. Methods: An electronic Liverpool Care Pathway was implemented in a specialized palliative care unit of a German university hospital. Its use is exemplified by means of auditing and analysis of the proportion of recorded items. Results: In the years 2013 and 2014 the electronic Liverpool Care Pathway was used for the care of 159 patients. The uptake of the instrument was high (67%). Most items were recorded. Apart from a high usability, the fast data retrieval allows fast analysis for auditing and research. Conclusions and discussion: The electronic instrument is feasible in a computerized ward and has strong advantages for retrospective analysis. Trial registration: Internal Clinical Trial Register of the Medical Faculty, Heinrich Heine University Düsseldorf, No. 2015124683 (7 December 2015). PMID:28970746

  15. A Fast and Sensitive New Satellite SO2 Retrieval Algorithm based on Principal Component Analysis: Application to the Ozone Monitoring Instrument

    NASA Technical Reports Server (NTRS)

    Li, Can; Joiner, Joanna; Krotkov, A.; Bhartia, Pawan K.

    2013-01-01

    We describe a new algorithm to retrieve SO2 from satellite-measured hyperspectral radiances. We employ the principal component analysis technique in regions with no significant SO2 to capture radiance variability caused by both physical processes (e.g., Rayleigh and Raman scattering and ozone absorption) and measurement artifacts. We use the resulting principal components and SO2 Jacobians calculated with a radiative transfer model to directly estimate SO2 vertical column density in one step. Application to the Ozone Monitoring Instrument (OMI) radiance spectra in 310.5-340 nm demonstrates that this approach can greatly reduce biases in the operational OMI product and decrease the noise by a factor of 2, providing greater sensitivity to anthropogenic emissions. The new algorithm is fast, eliminates the need for instrument-specific radiance correction schemes, and can be easily adapted to other sensors. These attributes make it a promising technique for producing longterm, consistent SO2 records for air quality and climate research.

  16. Data acquisition techniques for exploiting the uniqueness of the time-of-flight mass spectrometer: Application to sampling pulsed gas systems

    NASA Technical Reports Server (NTRS)

    Lincoln, K. A.

    1980-01-01

    Mass spectra are produced in most mass spectrometers by sweeping some parameter within the instrument as the sampled gases flow into the ion source. It is evident that any fluctuation in the gas during the sweep (mass scan) of the instrument causes the output spectrum to be skewed in its mass peak intensities. The time of flight mass spectrometer (TOFMS) with its fast, repetitive mode of operation produces spectra without skewing or varying instrument parameters and because all ion species are ejected from the ion source simultaneously, the spectra are inherently not skewed despite rapidly changing gas pressure or composition in the source. Methods of exploiting this feature by utilizing fast digital data acquisition systems, such as transient recorders and signal averagers which are commercially available are described. Applications of this technique are presented including TOFMS sampling of vapors produced by both pulsed and continuous laser heating of materials.

  17. Genetic evidence of a causal effect of insulin resistance on branched-chain amino acid levels.

    PubMed

    Mahendran, Yuvaraj; Jonsson, Anna; Have, Christian T; Allin, Kristine H; Witte, Daniel R; Jørgensen, Marit E; Grarup, Niels; Pedersen, Oluf; Kilpeläinen, Tuomas O; Hansen, Torben

    2017-05-01

    Fasting plasma levels of branched-chain amino acids (BCAAs) are associated with insulin resistance, but it remains unclear whether there is a causal relation between the two. We aimed to disentangle the causal relations by performing a Mendelian randomisation study using genetic variants associated with circulating BCAA levels and insulin resistance as instrumental variables. We measured circulating BCAA levels in blood plasma by NMR spectroscopy in 1,321 individuals from the ADDITION-PRO cohort. We complemented our analyses by using previously published genome-wide association study (GWAS) results from the Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) (n = 46,186) and from a GWAS of serum BCAA levels (n = 24,925). We used a genetic risk score (GRS), calculated using ten established fasting serum insulin associated variants, as an instrumental variable for insulin resistance. A GRS of three variants increasing circulating BCAA levels was used as an instrumental variable for circulating BCAA levels. Fasting plasma BCAA levels were associated with higher HOMA-IR in ADDITION-PRO (β 0.137 [95% CI 0.08, 0.19] p = 6 × 10 -7 ). However, the GRS for circulating BCAA levels was not associated with fasting insulin levels or HOMA-IR in ADDITION-PRO (β -0.011 [95% CI -0.053, 0.032] p = 0.6 and β -0.011 [95% CI -0.054, 0.031] p = 0.6, respectively) or in GWAS results for HOMA-IR from MAGIC (β for valine-increasing GRS -0.012 [95% CI -0.069, 0.045] p = 0.7). By contrast, the insulin-resistance-increasing GRS was significantly associated with increased BCAA levels in ADDITION-PRO (β 0.027 [95% CI 0.005, 0.048] p = 0.01) and in GWAS results for serum BCAA levels (β 1.22 [95% CI 0.71, 1.73] p = 4 × 10 -6 , β 0.96 [95% CI 0.45, 1.47] p = 3 × 10 -4 , and β 0.67 [95% CI 0.16, 1.18] p = 0.01 for isoleucine, leucine and valine levels, respectively) and instrumental variable analyses in ADDITION-PRO indicated that HOMA-IR is causally related to higher circulating fasting BCAA levels (β 0.73 [95% CI 0.26, 1.19] p = 0.002). Our results suggest that higher BCAA levels do not have a causal effect on insulin resistance while increased insulin resistance drives higher circulating fasting BCAA levels.

  18. Flow-induced birefringence measurement system using dual-crystal transverse electro-optic modulator for microgravity fluid physics applications

    NASA Technical Reports Server (NTRS)

    Mackey, Jeffrey R.

    1999-01-01

    We have developed a new instrument that can measure fast transient birefringence and polymer chain orientation angle in complex fluids. The instrument uses a dual-crystal transverse electro-optic modulator with the second crystal's modulation voltage applied 180 deg out of phase from that of the first crystal. In this manner, the second crystal compensates for the intrinsic static birefringence of the first crystal, and it doubles the modulation depth. By incorporating a transverse electro-optic modulator with two lithium-niobate (LiNbO3) crystals oriented orthogonal to each other with a custom-designed optical system, we have produced a very small robust instrument capable of fast transient retardation measurements. By measuring the sample thickness or optical path length through the sample, we can calculate the transient birefringence. This system can also measure dichroism. We have compared the calibration results and retardation and orientation angle measurements of this instrument with those of a photoelastic modulator (PEM) based system using a quarter wave plate and a high-precision 1/16-wave plate to simulate a birefringent sample. Transient birefringence measurements on the order of 10(exp -9) can be measured using either modulator.

  19. Unusual MRI findings in an immunocompetent patient with EBV encephalitis: a case report

    PubMed Central

    2011-01-01

    Blackground It is well-known that Epstein-Barr virus (EBV) can affect the central nervous system (CNS). Case presentation Herein the authors report unusual timely Magnetic Resonance Imaging (MRI) brain scan findings in an immunocompetent patient with EBV encephalitis. Diffusion weighted MRI sequence performed during the acute phase of the disease was normal, whereas the Fast Relaxation Fast Spin Echo T2 image showed diffuse signal intensity changes in white matter. The enhancement pattern suggested an inflammatory response restricted to the brain microcirculation. Acyclovir and corticosteroid therapy was administered. After three weeks, all signal intensities returned to normal and the patient showed clinical recovery. Conclusion This report demonstrates that EBV in an immunocompetent adult can present with diffuse, reversible brain white matter involvement in the acute phase of mononucleosis. Moreover, our case suggests that a negative DWI sequence is associated with a favorable improvement in severe EBV CNS infection. More extensive studies are needed to assess what other instrumental data can help to distinguish viral lesions from other causes in the acute phase of disease. PMID:21435249

  20. Temperature-controlled transparent-film heater based on silver nanowire-PMMA composite film

    NASA Astrophysics Data System (ADS)

    He, Xin; Liu, A.'lei; Hu, Xuyang; Song, Mingxia; Duan, Feng; Lan, Qiuming; Xiao, Jundong; Liu, Junyan; Zhang, Mei; Chen, Yeqing; Zeng, Qingguang

    2016-11-01

    We fabricated a high-performance film heater based on a silver nanowire and polymethyl methacrylate (Ag NW-PMMA) composite film, which was synthesized with the assistance of mechanical lamination and an in situ transfer method. The films exhibit excellent conductivity, high figure of merit, and strong adhesion of percolation network to substrate. By controlling NW density, we prepared the films with a transmittance of 44.9-85.0% at 550 nm and a sheet resistance of 0.13-1.40 Ω sq-1. A stable temperature ranging from 130 °C-40 °C was generated at 3.0 V within 10-30 s, indicating that the resulting film heaters show a rapid thermal response, low driving voltage and stable temperature recoverability. Furthermore, we demonstrated the applications of the film heater in defrosting and a physical therapeutic instrument. A fast defrosting on the composite film with a transmittance of 88% was observed by applying a 9 V driving voltage for 20 s. Meanwhile, we developed a physical therapeutic instrument with two modes of thermotherapy and electronic-pulse massage by using the composite films as two electrodes, greatly decreasing the weight and power consumption compared to a traditional instrument. Therefore, Ag NW-PMMA film can be a promising candidate for diversified heating applications.

  1. Transportable, Low-Dose Active Fast-Neutron Imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mihalczo, John T.; Wright, Michael C.; McConchie, Seth M.

    2017-08-01

    This document contains a description of the method of transportable, low-dose active fast-neutron imaging as developed by ORNL. The discussion begins with the technique and instrumentation and continues with the image reconstruction and analysis. The analysis discussion includes an example of how a gap smaller than the neutron production spot size and detector size can be detected and characterized depending upon the measurement time.

  2. Assessment of the high temperature fission chamber technology for the French fast reactor program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jammes, C.; Filliatre, P.; Geslot, B.

    2011-07-01

    High temperature fission chambers are key instruments for the control and protection of the sodium-cooled fast reactor. First, the developments of those neutron detectors, which are carried out either in France or abroad are reviewed. Second, the French realizations are assessed with the use of the technology readiness levels in order to identify tracks of improvement. (authors)

  3. FAST CHOPPER BUILDING, TRA665, INTERIOR. LOWER (DETECTOR) LEVEL. NOTE BRICKEDIN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FAST CHOPPER BUILDING, TRA-665, INTERIOR. LOWER (DETECTOR) LEVEL. NOTE BRICKED-IN WINDOW ON MTR SIDE. USED FOR STORAGE OF LEAD BRICKS AFTER EXPERIMENTAL NEUTRON INSTRUMENTS WERE REMOVED. SIGN SAYS "IN-PROCESS LEAD SOURCE STORAGE." INL NEGATIVE NO. HD-42-2. Mike Crane, Photographer, 3/2004 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  4. DAN instrument for NASA`s MSL mission: fast science data processing and instrument commanding for Mars surface operations and for field tests

    NASA Astrophysics Data System (ADS)

    Vostrukhin, A.; Kozyrev, A.; Litvak, M.; Malakhov, A.; Mitrofanov, I.; Mokrousov, M.; Sanin, A.; Tretyakov, V.

    2009-04-01

    The Dynamic Albedo of Neutrons (DAN) instrument is contributed by Russian Space Agency to NASA for Mars Science Laboratory mission which was originally scheduled for 2009 and now is shifted to 2011. The design of DAN instrument is partially inherited from HEND instrument for NASA's Mars Odyssey, which now successfully operates providing global mapping of martian neutron albedo, searching the distribution of martian water and observing the martian seasonal cycles. DAN is specially designed as an active neutron instrument for surface operations onboard mobile platforms. It is able to focus science investigations on local surface area around rover with horizontal resolution about 1 meter and vertical penetration about 0.5 m. The primary goal of DAN is the exploration of the hydrogen content of the bulk Martian subsurface material. This data will be used to estimate the content of chemically bound water in the hydrated minerals. The concept of DAN operations is based on combination of neutron activation analysis and neutron well logging tequnique, which are commonly used in the Earth geological applications. DAN consists blocks of Detectors and Electronics (DE) and Pulse Neutron Generator (PNG). The last one is used to irradiate the martian subsurface by pulses of 14MeV neutrons with changeable frequency up to 10 Hz. The first one detects post-pulse afterglow of neutrons, as they were thermalized down to epithermal and thermal energies within the martian subsurface. The result of detections are so called die away curves of neutrons afterglow, which show flux and time profile of thermalized neutrons and bring to us the observational signature of layering structure of martian regolith in part of depth distribution of Hydrogen (most effective element for thermalization of neutrons). In this study we focus on the development, verification and validation of DAN fast data processing and commanding. It is necessary to perform deconvolution from counting statistic in DAN detectors (raw data) to the real science products such as estimated average content of Hydrgen content or its depth distribution along the rover trace. For the rover surface operations it is necessary to provide real time data analysis to combine DAN data with data from all another science instruments and to develop the best observation strategy for the future periods of operation activity. In our approach we use: 1) Onboard FPGA data processing for recording neutron die away curves for epthermal and thermal neutrons of post-pulse afterglow 2) Getting raw data of DAN at the Mission operation center 3) Validation of instrument parameters and operational performance 4) Fast first level science data processing (statistical analysis, background subtraction, normalization) 5) Fast deconvolution of detector counts into the Hydrogen content (including numerical simulation, comparison with the known standard models of regolith), 6) Comparison with known information obtained with another instruments 7) Development of the near-term and long-term strategy for next DAN operations onboard MSL. 8) Generation and testing commanding sequences for the next period of MSL autonomous operations All this activity shall be adjusted in the real time, so the steps 2-8 shall not exceed 2-3 hours. Before launch we plan to validate this approach trough the instrument calibrations, field tests and MSL science group activity. The first experience will be presented of fast data analysis and commanding for the field tests of DAN, which were performed in the testing facility of the Joint Institute of Nuclear Research (Russia). Also, we will discuss our plans of DAN operations for coming field tests in Antarctica.

  5. Dose Calibration of the ISS-RAD Fast Neutron Detector

    NASA Technical Reports Server (NTRS)

    Zeitlin, C.

    2015-01-01

    The ISS-RAD instrument has been fabricated by Southwest Research Institute and delivered to NASA for flight to the ISS in late 2015 or early 2016. ISS-RAD is essentially two instruments that share a common interface to ISS. The two instruments are the Charged Particle Detector (CPD), which is very similar to the MSL-RAD detector on Mars, and the Fast Neutron Detector (FND), which is a boron-loaded plastic scintillator with readout optimized for the 0.5 to 10 MeV energy range. As the FND is completely new, it has been necessary to develop methodology to allow it to be used to measure the neutron dose and dose equivalent. This talk will focus on the methods developed and their implementation using calibration data obtained in quasi-monoenergetic (QMN) neutron fields at the PTB facility in Braunschweig, Germany. The QMN data allow us to determine an approximate response function, from which we estimate dose and dose equivalent contributions per detected neutron as a function of the pulse height. We refer to these as the "pSv per count" curves for dose equivalent and the "pGy per count" curves for dose. The FND is required to provide a dose equivalent measurement with an accuracy of ?10% of the known value in a calibrated AmBe field. Four variants of the analysis method were developed, corresponding to two different approximations of the pSv per count curve, and two different implementations, one for real-time analysis onboard ISS and one for ground analysis. We will show that the preferred method, when applied in either real-time or ground analysis, yields good accuracy for the AmBe field. We find that the real-time algorithm is more susceptible to chance-coincidence background than is the algorithm used in ground analysis, so that the best estimates will come from the latter.

  6. An ultra-fast EOD-based force-clamp detects rapid biomechanical transitions

    NASA Astrophysics Data System (ADS)

    Woody, Michael S.; Capitanio, Marco; Ostap, E. Michael; Goldman, Yale E.

    2017-08-01

    We assembled an ultra-fast infrared optical trapping system to detect mechanical events that occur less than a millisecond after a ligand binds to its filamentous substrate, such as myosin undergoing its 5 - 10 nm working stroke after actin binding. The instrument is based on the concept of Capitanio et al.1, in which a polymer bead-actin-bead dumbbell is held in two force-clamped optical traps. A force applied by the traps causes the filament to move at a constant velocity as hydrodynamic drag balances the applied load. When the ligand binds, the filament motion stops within 100 μs as the total force from the optical traps is transferred to the attachment. Subsequent translations signal active motions, such as the magnitude and timing of the motor's working stroke. In our instrument, the beads defining the dumbbell are held in independent force clamps utilizing a field-programmable gate array (FPGA) to update the trap beam positions at 250 kHz. We found that in our setup, acousto-optical deflectors (AODs) steering the beams were unsuitable for this purpose due to a slightly non-linear response in the beam intensity and deflection angle vs. the AOD ultra-sound wavelength, likely caused by low-amplitude standing acoustic waves in the deflectors. These aberrations caused instability in the force feedback loops leading to artefactual 20 nm jumps in position. This type of AOD non-linearity has been reported to be absent in electro-optical deflectors (EODs)2. We demonstrate that replacement of the AODs with EODs improves the performance of our instrument. Combining the superior beam-steering capability of the EODs, force acquisition via back-plane interferometry, and the dual high-speed FPGA-based feedback loops, we smoothly and precisely apply constant loads to study the dynamics of interactions between biological molecules such as actin and myosin.

  7. The TMT instrumentation program

    NASA Astrophysics Data System (ADS)

    Simard, Luc; Crampton, David; Ellerbroek, Brent; Boyer, Corinne

    2010-07-01

    An overview of the current status of the Thirty Meter Telescope (TMT) instrumentation program is presented. Conceptual designs for the three first light instruments (IRIS, WFOS and IRMS) are in progress, as well as feasibility studies of MIRES. Considerable effort is underway to understand the end-to-end performance of the complete telescopeadaptive optics-instrument system under realistic conditions on Mauna Kea. Highly efficient operation is being designed into the TMT system, based on a detailed investigation of the observation workflow to ensure very fast target acquisition and set up of all subsystems. Future TMT instruments will almost certainly involve contributions from institutions in many different locations in North America and partner nations. Coordinating and optimizing the design and construction of the instruments to ensure delivery of the best possible scientific capabilities is an interesting challenge. TMT welcomes involvement from all interested instrument teams.

  8. 40 CFR 205.2 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... in decibels. (10) Highway means the streets, roads, and public ways in any State. (11) Fast Meter Response means that the fast dynamic response of the sound level meter shall be used. The fast dynamic...

  9. 40 CFR 205.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... in decibels. (10) Highway means the streets, roads, and public ways in any State. (11) Fast Meter Response means that the fast dynamic response of the sound level meter shall be used. The fast dynamic...

  10. 40 CFR 205.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... in decibels. (10) Highway means the streets, roads, and public ways in any State. (11) Fast Meter Response means that the fast dynamic response of the sound level meter shall be used. The fast dynamic...

  11. 40 CFR 205.2 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... in decibels. (10) Highway means the streets, roads, and public ways in any State. (11) Fast Meter Response means that the fast dynamic response of the sound level meter shall be used. The fast dynamic...

  12. Assessing the Potential Effectiveness of Food and Beverage Taxes and Subsidies for Improving Public Health: A Systematic Review of Prices, Demand and Body Weight Outcomes

    PubMed Central

    Powell, Lisa M.; Chriqui, Jamie F.; Khan, Tamkeen; Wada, Roy; Chaloupka, Frank J.

    2012-01-01

    Taxes and subsidies are increasingly being considered as potential policy instruments to incentivize consumers to improve their food and beverage consumption patterns and related health outcomes. This study provided a systematic review of recent U.S. studies on the price elasticity of demand for sugar-sweetened beverages (SSBs), fast food and fruits and vegetables as well as the direct associations of prices/taxes with body weight outcomes. Based on the recent literature, the price elasticity of demand for SSBs, fast food, fruits and vegetables was estimated to be −1.21, −0.52, −0.49 and −0.48, respectively. The studies that linked soda taxes to weight outcomes showed minimal impacts on weight; however, they were based on existing state-level sales taxes that were relatively low. Higher fast-food prices were associated with lower weight outcomes particularly among adolescents suggesting that raising prices would potentially impact weight outcomes. Lower fruit and vegetable prices were generally found to be associated with lower body weight outcomes among both low-income children and adults suggesting that subsidies that would reduce the cost of fruits and vegetables for lower-socioeconomic populations may be effective in reducing obesity. Pricing instruments should continue to be considered and evaluated as potential policy instruments to address public health risks. PMID:23174017

  13. The ISAC-CNR micrometeorological base and database in Lecce

    NASA Astrophysics Data System (ADS)

    Martano, P.; Grasso, F.; Elefante, C.

    2010-09-01

    The micrometeorological base of CNR-ISAC in Lecce, South-East of Italy, is active since 2002, in collecting experimental data about surface-atmosphere transfer of momentum heat and water vapour. It operates in a periurban site inside the Salento University campus and has been improved along the past years in terms of active sensors to give a quite complete description of the soil-atmosphere vertical transfer. It is composed by a 16 m mast with fast response (eddy correlation) instrumentation and an ancillary automatic meteorological station collecting also soil data at 2 levels depth. Fast response data are pre-processed in half-hour averaged statistics. All collected data are available in a web database (www.basesperimentale.le.isac.cnr.it) where they can be visualized or downloaded. A real time automated connection between the base and the data base is also in progress. At present the Lecce data base is also a pilot reference structure for the Climate Change Section of the CNR-DTA GIIDA project (National Research Council - Earth and Environment Department, Interdisciplinary and Interoperational Management of Environmental Data), aimed to build a spatial data infrastructure between different CNR-DTA structures collecting environmental data. This will allow easier search and availability for a great deal of environmental information in terms of data associated to international quality standards and metadata systems (GEOSS, GMES, INSPIRE).

  14. Quantitative analysis of volatile organic compounds using ion mobility spectra and cascade correlation neural networks

    NASA Technical Reports Server (NTRS)

    Harrington, Peter DEB.; Zheng, Peng

    1995-01-01

    Ion Mobility Spectrometry (IMS) is a powerful technique for trace organic analysis in the gas phase. Quantitative measurements are difficult, because IMS has a limited linear range. Factors that may affect the instrument response are pressure, temperature, and humidity. Nonlinear calibration methods, such as neural networks, may be ideally suited for IMS. Neural networks have the capability of modeling complex systems. Many neural networks suffer from long training times and overfitting. Cascade correlation neural networks train at very fast rates. They also build their own topology, that is a number of layers and number of units in each layer. By controlling the decay parameter in training neural networks, reproducible and general models may be obtained.

  15. Modification of wave propagation and wave travel-time by the presence of magnetic fields in the solar network atmosphere

    NASA Astrophysics Data System (ADS)

    Nutto, C.; Steiner, O.; Schaffenberger, W.; Roth, M.

    2012-02-01

    Context. Observations of waves at frequencies above the acoustic cut-off frequency have revealed vanishing wave travel-times in the vicinity of strong magnetic fields. This detection of apparently evanescent waves, instead of the expected propagating waves, has remained a riddle. Aims: We investigate the influence of a strong magnetic field on the propagation of magneto-acoustic waves in the atmosphere of the solar network. We test whether mode conversion effects can account for the shortening in wave travel-times between different heights in the solar atmosphere. Methods: We carry out numerical simulations of the complex magneto-atmosphere representing the solar magnetic network. In the simulation domain, we artificially excite high frequency waves whose wave travel-times between different height levels we then analyze. Results: The simulations demonstrate that the wave travel-time in the solar magneto-atmosphere is strongly influenced by mode conversion. In a layer enclosing the surface sheet defined by the set of points where the Alfvén speed and the sound speed are equal, called the equipartition level, energy is partially transferred from the fast acoustic mode to the fast magnetic mode. Above the equipartition level, the fast magnetic mode is refracted due to the large gradient of the Alfvén speed. The refractive wave path and the increasing phase speed of the fast mode inside the magnetic canopy significantly reduce the wave travel-time, provided that both observing levels are above the equipartition level. Conclusions: Mode conversion and the resulting excitation and propagation of fast magneto-acoustic waves is responsible for the observation of vanishing wave travel-times in the vicinity of strong magnetic fields. In particular, the wave propagation behavior of the fast mode above the equipartition level may mimic evanescent behavior. The present wave propagation experiments provide an explanation of vanishing wave travel-times as observed with multi-line high-cadence instruments. Movies are available in electronic form at http://www.aanda.org

  16. A Variational Method to Retrieve the Extinction Profile in Liquid Clouds Using Multiple Field-of-View Lidar

    NASA Technical Reports Server (NTRS)

    Pounder, Nicola L.; Hogan, Robin J.; Varnai, Tamas; Battaglia, Alessandro; Cahalan, Robert F.

    2011-01-01

    While liquid clouds playa very important role in the global radiation budget, it's been very difficult to remotely determine their internal cloud structure. Ordinary lidar instruments (similar to radars but using visible light pulses) receive strong signals from such clouds, but the information is limited to a thin layer near the cloud boundary. Multiple field-of-view (FOV) lidars offer some new hope as they are able to isolate photons that were scattered many times by cloud droplets and penetrated deep into a cloud before returning to the instrument. Their data contains new information on cloud structure, although the lack of fast simulation methods made it challenging to interpret the observations. This paper describes a fast new technique that can simulate multiple-FOV lidar signals and can even estimate the way the signals would change in response to changes in cloud properties-an ability that allows quick refinements in our initial guesses of cloud structure. Results for a hypothetical airborne three-FOV lidar suggest that this approach can help determine cloud structure for a deeper layer in clouds, and can reliably determine the optical thickness of even fairly thick liquid clouds. The algorithm is also applied to stratocumulus observations by the 8-FOV airborne "THOR" lidar. These tests demonstrate that the new method can determine the depth to which a lidar provides useful information on vertical cloud structure. This work opens the way to exploit data from spaceborne lidar and radar more rigorously than has been possible up to now.

  17. Expanding neurochemical investigations with multi-modal recording: simultaneous fast-scan cyclic voltammetry, iontophoresis, and patch clamp measurements.

    PubMed

    Kirkpatrick, D C; McKinney, C J; Manis, P B; Wightman, R M

    2016-08-02

    Multi-modal recording describes the simultaneous collection of information across distinct domains. Compared to isolated measurements, such studies can more easily determine relationships between varieties of phenomena. This is useful for neurochemical investigations which examine cellular activity in response to changes in the local chemical environment. In this study, we demonstrate a method to perform simultaneous patch clamp measurements with fast-scan cyclic voltammetry (FSCV) using optically isolated instrumentation. A model circuit simulating concurrent measurements was used to predict the electrical interference between instruments. No significant impact was anticipated between methods, and predictions were largely confirmed experimentally. One exception was due to capacitive coupling of the FSCV potential waveform into the patch clamp amplifier. However, capacitive transients measured in whole-cell current clamp recordings were well below the level of biological signals, which allowed the activity of cells to be easily determined. Next, the activity of medium spiny neurons (MSNs) was examined in the presence of an FSCV electrode to determine how the exogenous potential impacted nearby cells. The activities of both resting and active MSNs were unaffected by the FSCV waveform. Additionally, application of an iontophoretic current, used to locally deliver drugs and other neurochemicals, did not affect neighboring cells. Finally, MSN activity was monitored during iontophoretic delivery of glutamate, an excitatory neurotransmitter. Membrane depolarization and cell firing were observed concurrently with chemical changes around the cell resulting from delivery. In all, we show how combined electrophysiological and electrochemical measurements can relate information between domains and increase the power of neurochemical investigations.

  18. Fast word reading in pure alexia: "fast, yet serial".

    PubMed

    Bormann, Tobias; Wolfer, Sascha; Hachmann, Wibke; Neubauer, Claudia; Konieczny, Lars

    2015-01-01

    Pure alexia is a severe impairment of word reading in which individuals process letters serially with a pronounced length effect. Yet, there is considerable variation in the performance of alexic readers with generally very slow, but also occasionally fast responses, an observation addressed rarely in previous reports. It has been suggested that "fast" responses in pure alexia reflect residual parallel letter processing or that they may even be subserved by an independent reading system. Four experiments assessed fast and slow reading in a participant (DN) with pure alexia. Two behavioral experiments investigated frequency, neighborhood, and length effects in forced fast reading. Two further experiments measured eye movements when DN was forced to read quickly, or could respond faster because words were easier to process. Taken together, there was little support for the proposal that "qualitatively different" mechanisms or reading strategies underlie both types of responses in DN. Instead, fast responses are argued to be generated by the same serial-reading strategy.

  19. The ARC (Astrophysical Research Consortium) telescope project.

    NASA Astrophysics Data System (ADS)

    Anderson, K. S.

    A consortium of universities intends to construct a 3.5 meter optical-infrared telescope at a site in south-central New Mexico. The use of innovative mirror technology, a fast primary, and an alt-azimuth mounting results in a compact and lightweight instrument. This telescope will be uniquely well-suited for addressing certain observational programs by virtue of its capability for fully remote operation and rapid instrument changes.

  20. Multiple-User, Multitasking, Virtual-Memory Computer System

    NASA Technical Reports Server (NTRS)

    Generazio, Edward R.; Roth, Don J.; Stang, David B.

    1993-01-01

    Computer system designed and programmed to serve multiple users in research laboratory. Provides for computer control and monitoring of laboratory instruments, acquisition and anlaysis of data from those instruments, and interaction with users via remote terminals. System provides fast access to shared central processing units and associated large (from megabytes to gigabytes) memories. Underlying concept of system also applicable to monitoring and control of industrial processes.

  1. Transcriptional and chromatin regulation during fasting – The genomic era

    PubMed Central

    Goldstein, Ido; Hager, Gordon L.

    2015-01-01

    An elaborate metabolic response to fasting is orchestrated by the liver and is heavily reliant upon transcriptional regulation. In response to hormones (glucagon, glucocorticoids) many transcription factors (TFs) are activated and regulate various genes involved in metabolic pathways aimed at restoring homeostasis: gluconeogenesis, fatty acid oxidation, ketogenesis and amino acid shuttling. We summarize the recent discoveries regarding fasting-related TFs with an emphasis on genome-wide binding patterns. Collectively, the summarized findings reveal a large degree of co-operation between TFs during fasting which occurs at motif-rich DNA sites bound by a combination of TFs. These new findings implicate transcriptional and chromatin regulation as major determinants of the response to fasting and unravels the complex, multi-TF nature of this response. PMID:26520657

  2. Effects of fasting and feeding on the fast-start swimming performance of southern catfish Silurus meridionalis.

    PubMed

    Yan, G J; He, X K; Cao, Z D; Fu, S J

    2015-01-21

    This study investigated the effects of fasting and feeding on the fast-start escape swimming performance of juvenile southern catfish Silurus meridionalis, a sit-and-wait forager that encounters extreme fasting and famine frequently during its lifespan. Ten to 30 days of fasting resulted in no significant change in most of the variables measured in the fast-start response except a 20-30% decrease in the escape distance during the first 120 ms (D 120ms ) relative to the control group (48 h after feeding). The ratio of the single-bend (SB) response (lower energetic expenditure) to the double-bend (DB) response increased significantly from 0% in the control group to 75 and 82·5% in the 20 and 30 day fasting groups, respectively. Satiated feeding (25% of body mass) resulted in a significantly lower (36·6%) maximum linear velocity (V max ) and a significantly lower (43·3%) D 120ms than in non-fed fish (control group, 48 h after feeding). Half-satiated feeding (12·5% of body mass), however, showed no significant effects on any of the measured variables of the fast-start response relative to control fish. It is suggested that the increase in the ratio of SB:DB responses with fasting in S. meridionalis may reflect a trade-off between energy conservation and maintaining high V max , while variables of fast-start performance were more sensitive to feeding than fasting might be an adaptive strategy to their foraging mode and food availability in their habitat. © 2015 The Fisheries Society of the British Isles.

  3. Multispecies breath analysis faster than a single respiratory cycle by optical-feedback cavity-enhanced absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Ventrillard-Courtillot, Irene; Gonthiez, Thierry; Clerici, Christine; Romanini, Daniel

    2009-11-01

    We demonstrate a first application, of optical-feedback cavity-enhanced absorption spectroscopy (OF-CEAS) to breath analysis in a medical environment. Noninvasive monitoring of trace species in exhaled air was performed simultaneous to spirometric measurements on patients at Bichat Hospital (Paris). The high selectivity of the OF-CEAS spectrometer and a time response of 0.3 s (limited by sample flow rate) allowed following the evolution of carbon monoxide and methane concentrations during individual respiratory cycles, and resolving variations among different ventilatory patterns. The minimum detectable absorption on this time scale is about 3×10-10 cm-1. At the working wavelength of the instrument (2.326 μm), this translates to concentration detection limits of ~1 ppbv (45 picomolar, or ~1.25 μg/m3) for CO and 25 ppbv for CH4, well below concentration values found in exhaled air. This same instrument is also able to provide measurement of NH3 concentrations with a detection limit of ~10 ppbv however, at present, memory effects do not allow its measurement on fast time scales.

  4. Portable fluorescence lifetime spectroscopy system for in-situ interrogation of biological tissues.

    PubMed

    Saito Nogueira, Marcelo; Cosci, Alessandro; Teixeira Rosa, Ramon Gabriel; Salvio, Ana Gabriela; Pratavieira, Sebastião; Kurachi, Cristina

    2017-10-01

    Fluorescence spectroscopy and lifetime techniques are potential methods for optical diagnosis and characterization of biological tissues with an in-situ, fast, and noninvasive interrogation. Several diseases may be diagnosed due to differences in the fluorescence spectra of targeted fluorophores, when, these spectra are similar, considering steady-state fluorescence, others may be detected by monitoring their fluorescence lifetime. Despite this complementarity, most of the current fluorescence lifetime systems are not robust and portable, and not being feasible for clinical applications. We describe the assembly of a fluorescence lifetime spectroscopy system in a suitcase, its characterization, and validation with clinical measurements of skin lesions. The assembled system is all encased and robust, maintaining its mechanical, electrical, and optical stability during transportation, and is feasible for clinical measurements. The instrument response function measured was about 300 ps, and the system is properly calibrated. At the clinical study, the system showed to be reliable, and the achieved spectroscopy results support its potential use as an auxiliary tool for skin diagnostics. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  5. Measurement of tropospheric OH and HO2 by laser-induced fluorescence at low pressure

    NASA Technical Reports Server (NTRS)

    Stevens, P. S.; Mather, J. H.; Brune, W. H.

    1994-01-01

    The hydroxyl radical (OH) is the primary oxidant in the atmosphere, responsible for many photochemical reactions that affect both regional air quality and global climate change. Because of its high reactivity, abundances of OH in the troposphere are less than 1 part per trillion by volume (pptv) and thus difficult to measure accurately. This paper describes an instrument for the sensitive detection of OH in the troposphere using low-pressure laser-induced fluorescence. Ambient air is expanded into a low pressure detection chamber, and OH is both excited and detected using the A(sup 2) Epsilon(+)(v prime = 0) yields X(sup 2)Pi(v double prime = 0) transition near 308 nm. An injector upstream of the detection axis allows for the addition of reagent NO to convert ambient HO2 to OH using the fast reaction HO2 + NO yields OH + NO2. Using recent advances in laser and detector technologies, this prototype instrument is able to detect less than 1 x 10(exp 5) molecules/cu cm (0.004 pptv) of OH with an integration time of 30 s with negligible interferences.

  6. Probing fast ribozyme reactions under biological conditions with rapid quench-flow kinetics.

    PubMed

    Bingaman, Jamie L; Messina, Kyle J; Bevilacqua, Philip C

    2017-05-01

    Reaction kinetics on the millisecond timescale pervade the protein and RNA fields. To study such reactions, investigators often perturb the system with abiological solution conditions or substrates in order to slow the rate to timescales accessible by hand mixing; however, such perturbations can change the rate-limiting step and obscure key folding and chemical steps that are found under biological conditions. Mechanical methods for collecting data on the millisecond timescale, which allow these perturbations to be avoided, have been developed over the last few decades. These methods are relatively simple and can be conducted on affordable and commercially available instruments. Here, we focus on using the rapid quench-flow technique to study the fast reaction kinetics of RNA enzymes, or ribozymes, which often react on the millisecond timescale under biological conditions. Rapid quench of ribozymes is completely parallel to the familiar hand-mixing approach, including the use of radiolabeled RNAs and fractionation of reactions on polyacrylamide gels. We provide tips on addressing and preventing common problems that can arise with the rapid-quench technique. Guidance is also offered on ensuring the ribozyme is properly folded and fast-reacting. We hope that this article will facilitate the broader use of rapid-quench instrumentation to study fast-reacting ribozymes under biological reaction conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Probing fast ribozyme reactions under biological conditions with rapid quench-flow kinetics

    PubMed Central

    Bingaman, Jamie L.; Messina, Kyle J.; Bevilacqua, Philip C.

    2017-01-01

    Reaction kinetics on the millisecond timescale pervade the protein and RNA fields. To study such reactions, investigators often perturb the system with abiological solution conditions or substrates in order to slow the rate to timescales accessible by hand-mixing; however, such perturbations can change the rate-limiting step and obscure key folding and chemical steps that are found under biological conditions. Mechanical methods for collecting data on the millisecond timescale, which allow these perturbations to be avoided, have been developed over the last few decades. These methods are relatively simple and can be conducted on affordable and commercially available instruments. Here, we focus on using the rapid quench-flow technique to study the fast reaction kinetics of RNA enzymes, or ribozymes, which often react on the millisecond timescale under biological conditions. Rapid quench of ribozymes is completely parallel to the familiar hand-mixing approach, including the use of radiolabeled RNAs and fractionation of reactions on polyacrylamide gels. We provide tips on addressing and preventing common problems that can arise with the rapid-quench technique. Guidance is also offered on ensuring the ribozyme is properly folded and fast-reacting. We hope that this article will facilitate the broader use of rapid-quench instrumentation to study fast-reacting ribozymes under biological reaction conditions. PMID:28315484

  8. On the fast zonal transport of the STS-121 space shuttle exhaust plume in the lower thermosphere

    NASA Astrophysics Data System (ADS)

    Yue, Jia; Liu, Han-Li; Meier, R. R.; Chang, Loren; Gu, Sheng-Yang; Russell, James, III

    2013-03-01

    Meier et al. (2011) reported rapid eastward transport of the STS-121 space shuttle (launch: July 4, 2006) main engine plume in the lower thermosphere, observed in hydrogen Lyman α images by the GUVI instrument onboard the TIMED satellite. In order to study the mechanism of the rapid zonal transport, diagnostic tracer calculations are performed using winds from the Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIME-GCM) simulation of July, 2006. It is found that the strong eastward jet at heights of 100-110 km, where the exhaust plume was deposited, results in a persistent eastward tracer motion with an average velocity of 45 m/s. This is generally consistent with, though faster than, the prevailing eastward shuttle plume movement with daily mean velocity of 30 m/s deduced from the STS-121 GUVI observation. The quasi-two-day wave (QTDW) was not included in the numerical simulation because it was found not to be large. Its absence, however, might be partially responsible for insufficient meridional transport to move the tracers away from the fast jet in the simulation. The current study and our model results from Yue and Liu (2010) explain two very different shuttle plume transport scenarios (STS-121 and STS-107 (launch: January 16, 2003), respectively): we conclude that lower thermospheric dynamics is sufficient to account for both very fast zonal motion (zonal jet in the case of STS-121) and very fast meridional motion to polar regions (large QTDW in the case of STS-107).

  9. FAST Simulation Tool Containing Methods for Predicting the Dynamic Response of Wind Turbines

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jonkman, Jason

    2015-08-12

    FAST is a simulation tool (computer software) for modeling tlie dynamic response of horizontal-axis wind turbines. FAST employs a combined modal and multibody structural-dynamics formulation in the time domain.

  10. Extreme Performance Scalable Operating Systems Final Progress Report (July 1, 2008 - October 31, 2011)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Malony, Allen D; Shende, Sameer

    This is the final progress report for the FastOS (Phase 2) (FastOS-2) project with Argonne National Laboratory and the University of Oregon (UO). The project started at UO on July 1, 2008 and ran until April 30, 2010, at which time a six-month no-cost extension began. The FastOS-2 work at UO delivered excellent results in all research work areas: * scalable parallel monitoring * kernel-level performance measurement * parallel I/0 system measurement * large-scale and hybrid application performance measurement * onlne scalable performance data reduction and analysis * binary instrumentation

  11. Experimental Measurements of Concentration Fluctuations and Scales in a Dispersing Plume in the Atmospheric Surface Layer Obtained Using a Very Fast Response Concentration Detector

    DTIC Science & Technology

    2016-06-14

    Very Fast Response Concentration Detector EUGENE YEE Defence Research Establishment Suffield, Medicine Hat, Alberta, Canada R. CHAN AND P. R...hazards posed by the release of highly toxic or flammable gases to an un- derstanding of fast nonlinear physicochemical pro- cesses required for the...e.g., Gifford 1959; Csanady 1967; Chatwin 1982), fast -response concentration sensors required for the measurement and characterization of the

  12. A Concept for Seeing-Limited Near-IR Spectroscopy on the Giant Magellan Telescope

    NASA Astrophysics Data System (ADS)

    Simcoe, Robert A.; Furesz, Gabor; Egan, Mark; Malonis, Andrew; Hellickson, Tim

    2016-09-01

    We present a simple seeing-limited IR spectrometer design for the Giant Magellan Telescope, with continuous R = 6000 coverage from 0.87-2.50 microns for a 0:7" slit. The instrument's design is based on an asymmetric white pupil echelle layout, with dichroics splitting the optical train into yJ, H, and K channels after the pupil transfer mirror. A separate low-dispersion mode offers single-object R ~ 850 spectra which also cover the full NIR bandpass in each exposure. Catalog gratings and H2RG detectors are used to minimize cost, and only two cryogenic rotary mechanisms are employed, reducing mechanical complexity. The instrument dewar occupies an envelope of 1:8×1:5×1:2 meters, satisfying mass and volume requirements for GMT with comfortable margin. We estimate the system throughput at ~35% including losses from the atmosphere, telescope, and instrument (i.e. all coatings, gratings, and sensors). This optical efficiency is comparable to the FIRE spectrograph on Magellan, and we have specified and designed fast cameras so the GMT instrument will have an almost identical pixel scale as FIRE. On the 6.5 meter Magellan telescopes, FIRE is read-noise limited in the y and J bands, similar to other existing near-IR spectrometers and also to JWST/NIRSPEC. GMT's twelve-fold increase in collecting area will therefore offer gains in signal-to-noise per exposure that exceed those of moderate resolution optical instruments, which are already sky-noise limited on today's telescopes. Such an instrument would allow GMT to pursue key early science programs on the Epoch of Reionization, galaxy formation, transient astronomy, and obscured star formation environments prior to commissioning of its adaptive optics system. This design study demonstrates the feasibility of developing relatively affordable spectrometers at the ELT scale, in response to the pressures of joint funding for these telescopes and their associated instrument suites.

  13. Fast or slow? Compressions (or not) in number-to-line mappings.

    PubMed

    Candia, Victor; Deprez, Paola; Wernery, Jannis; Núñez, Rafael

    2015-01-01

    We investigated, in a university student population, spontaneous (non-speeded) fast and slow number-to-line mapping responses using non-symbolic (dots) and symbolic (words) stimuli. Seeking for less conventionalized responses, we used anchors 0-130, rather than the standard 0-100. Slow responses to both types of stimuli only produced linear mappings with no evidence of non-linear compression. In contrast, fast responses revealed distinct patterns of non-linear compression for dots and words. A predicted logarithmic compression was observed in fast responses to dots in the 0-130 range, but not in the reduced 0-100 range, indicating compression in proximity of the upper anchor 130, not the standard 100. Moreover, fast responses to words revealed an unexpected significant negative compression in the reduced 0-100 range, but not in the 0-130 range, indicating compression in proximity to the lower anchor 0. Results show that fast responses help revealing the fundamentally distinct nature of symbolic and non-symbolic quantity representation. Whole number words, being intrinsically mediated by cultural phenomena such as language and education, emphasize the invariance of magnitude between them—essential for linear mappings, and therefore, unlike non-symbolic (psychophysical) stimuli, yield spatial mappings that don't seem to be influenced by the Weber-Fechner law of psychophysics. However, high levels of education (when combined with an absence of standard upper anchors) may lead fast responses to overestimate magnitude invariance on the lower end of word numerals.

  14. Intercomparison of fast response commercial gas analysers for nitrous oxide flux measurements under field conditions

    NASA Astrophysics Data System (ADS)

    Rannik, Ü.; Haapanala, S.; Shurpali, N. J.; Mammarella, I.; Lind, S.; Hyvönen, N.; Peltola, O.; Zahniser, M.; Martikainen, P. J.; Vesala, T.

    2015-01-01

    Four gas analysers capable of measuring nitrous oxide (N2O) concentration at a response time necessary for eddy covariance flux measurements were operated from spring until winter 2011 over a field cultivated with reed canary grass (RCG, Phalaris arundinacea, L.), a perennial bioenergy crop in eastern Finland. The instruments were TGA100A (Campbell Scientific Inc.), CW-TILDAS-CS (Aerodyne Research Inc.), N2O / CO-23d (Los Gatos Research Inc.) and QC-TILDAS-76-CS (Aerodyne Research Inc.). The period with high emissions, lasting for about 2 weeks after fertilization in late May, was characterized by an up to 2 orders of magnitude higher emission, whereas during the rest of the campaign the N2O fluxes were small, from 0.01 to 1 nmol m-2 s-1. Two instruments, CW-TILDAS-CS and N2O / CO-23d, determined the N2O exchange with minor systematic difference throughout the campaign, when operated simultaneously. TGA100A produced the cumulatively highest N2O estimates (with 29% higher values during the period when all instruments were operational). QC-TILDAS-76-CS obtained 36% lower fluxes than CW-TILDAS-CS during the first period, including the emission episode, whereas the correspondence with other instruments during the rest of the campaign was good. The reasons for systematic differences were not identified, suggesting further need for detailed evaluation of instrument performance under field conditions with emphasis on stability, calibration and any other factors that can systematically affect the accuracy of flux measurements. The instrument CW-TILDAS-CS was characterized by the lowest noise level (with a standard deviation of around 0.12 ppb at 10 Hz sampling rate) as compared to N2O / CO-23d and QC-TILDAS-76-CS (around 0.50 ppb) and TGA100A (around 2 ppb). We identified that for all instruments except CW-TILDAS-CS the random error due to instrumental noise was an important source of uncertainty at the 30 min averaging level and the total stochastic error was frequently of the same magnitude as the fluxes when N2O exchange was small at the measurement site. Both instruments based on continuous-wave quantum cascade laser, CW-TILDAS-CS and N2O / CO-23d, were able to determine the same sample of low N2O fluxes with a high mutual coefficient of determination at the 30 min averaging level and with minor systematic difference over the observation period of several months. This enables us to conclude that the new-generation instrumentation is capable of measuring small N2O exchange with high precision and accuracy at sites with low fluxes.

  15. Can Fast and Slow Intelligence Be Differentiated?

    ERIC Educational Resources Information Center

    Partchev, Ivailo; De Boeck, Paul

    2012-01-01

    Responses to items from an intelligence test may be fast or slow. The research issue dealt with in this paper is whether the intelligence involved in fast correct responses differs in nature from the intelligence involved in slow correct responses. There are two questions related to this issue: 1. Are the processes involved different? 2. Are the…

  16. Kruppel-like factor 15 is required for the cardiac adaptive response to fasting.

    PubMed

    Sugi, Keiki; Hsieh, Paishiun N; Ilkayeva, Olga; Shelkay, Shamanthika; Moroney, Bridget; Baadh, Palvir; Haynes, Browning; Pophal, Megan; Fan, Liyan; Newgard, Christopher B; Prosdocimo, Domenick A; Jain, Mukesh K

    2018-01-01

    Cardiac metabolism is highly adaptive in response to changes in substrate availability, as occur during fasting. This metabolic flexibility is essential to the maintenance of contractile function and is under the control of a group of select transcriptional regulators, notably the nuclear receptor family of factors member PPARα. However, the diversity of physiologic and pathologic states through which the heart must sustain function suggests the possible existence of additional transcriptional regulators that play a role in matching cardiac metabolism to energetic demand. Here we show that cardiac KLF15 is required for the normal cardiac response to fasting. Specifically, we find that cardiac function is impaired upon fasting in systemic and cardiac specific Klf15-null mice. Further, cardiac specific Klf15-null mice display a fasting-dependent accumulation of long chain acylcarnitine species along with a decrease in expression of the carnitine translocase Slc25a20. Treatment with a diet high in short chain fatty acids relieves the KLF15-dependent long chain acylcarnitine accumulation and impaired cardiac function in response to fasting. Our observations establish KLF15 as a critical mediator of the cardiac adaptive response to fasting through its regulation of myocardial lipid utilization.

  17. Never Say No … How the Brain Interprets the Pregnant Pause in Conversation

    PubMed Central

    Bögels, Sara; Kendrick, Kobin H.; Levinson, Stephen C.

    2015-01-01

    In conversation, negative responses to invitations, requests, offers, and the like are more likely to occur with a delay–conversation analysts talk of them as dispreferred. Here we examine the contrastive cognitive load ‘yes’ and ‘no’ responses make, either when relatively fast (300 ms after question offset) or delayed (1000 ms). Participants heard short dialogues contrasting in speed and valence of response while having their EEG recorded. We found that a fast ‘no’ evokes an N400-effect relative to a fast ‘yes’; however, this contrast disappeared in the delayed responses. 'No' responses, however, elicited a late frontal positivity both if they were fast and if they were delayed. We interpret these results as follows: a fast ‘no’ evoked an N400 because an immediate response is expected to be positive–this effect disappears as the response time lengthens because now in ordinary conversation the probability of a ‘no’ has increased. However, regardless of the latency of response, a ‘no’ response is associated with a late positivity, since a negative response is always dispreferred. Together these results show that negative responses to social actions exact a higher cognitive load, but especially when least expected, in immediate response. PMID:26699335

  18. The Effect of Fasting Duration on Baseline Blood Glucose Concentration, Blood Insulin Concentration, Glucose/Insulin Ratio, Oral Sugar Test, and Insulin Response Test Results in Horses.

    PubMed

    Bertin, F R; Taylor, S D; Bianco, A W; Sojka-Kritchevsky, J E

    2016-09-01

    Published descriptions of the oral sugar test (OST) and insulin response test (IRT) have been inconsistent when specifying the protocol for fasting horses before testing. The purpose of our study was to examine the effect of fasting duration on blood glucose concentration, blood insulin concentration, glucose/insulin ratio, OST, and IRT results in horses. Ten healthy adult horses. Both OST and IRT were performed on horses without fasting and after fasting for 3, 6, and 12 hours. Thus, 8 tests were performed per horse in a randomized order. Blood collected at the initial time point of the OST was analysed for both blood glucose and serum insulin concentrations so that baseline concentrations and the glucose/insulin ratio could be determined. Unless fasted, horses had free-choice access to grass hay. There was no effect of fasting and fasting duration on blood glucose concentration, serum insulin concentration, glucose/insulin ratio, or the OST. Response to insulin in the IRT was decreased in fasted horses. The effect increased with fasting duration, with the least response to insulin administration after a 12-hour fast. These data indicate that insulin sensitivity is not a fixed trait in horses. Fasting a horse is not recommended for a glucose/insulin ratio or IRT, and fasting a horse for 3 hours is recommended for the OST. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  19. Research of built-in self test technology on cable-free self-positioning seismograph

    NASA Astrophysics Data System (ADS)

    Huaizhu, Z.; Lin, J.; Chen, Z.; Zhang, L.; Yang, H.; Zheng, F.

    2011-12-01

    Cable-free self-positioning seismograph is the key instrument and equipment required for deep seismic exploration in China. In order to measure the performance of seismic data acquisition systems whether meet exploration requirements , to ensure the accuracy of seismic data, and to ensure equipment reliability and stability, a built-in self test solution of the cable-free self-positioning seismic recorder is provided. Within a 24-bits Σ-Δ DAC, the seismograph can produce sine, step, pulse and other high-precision analog test signal, with dynamic range of 120dB or more, through the FPGA to control the analog multiplexer switching the input signal acquisition channels, and start the 24-bit Σ-Δ ADC in the instrument internal simultaneously to acquisition the test signal data, carries on the fast Fournier transformation by instrument internal CPU, to achieve the instrument of analysis and calculation of performance indicators, including: the equivalent noise and drift, common mode rejection ratio (CMRR), crosstalk, harmonic distortion, dynamic range, channel response consistency, detector impulse response , etc. A lot of testing experiments about the various parameters were performed and studied currently. By setting different sampling rate (1Hz, 5Hz, ..., 4kHz), each of the measurement system noise level was measured, and the maximum noise is about 0.5μV; the crosstalk between channels was tested using the 31.25Hz sine wave, the result is more than-120dB with sampling rate of 1kHz; the harmonic distortion was measured by adding the high-precision sine wave signals of different frequencies, such as 500Hz, 250 Hz, 125 Hz, 62.5 Hz, 31.25 Hz, 15.625 Hz, 7.812 Hz, 3.90625Hz, etc. the calculated results is in-118dB or more. The experimental results show that, the parameters of the cable-free self-positioning of the seismic recorder meet the technical requirements for the deep exploration, compared to the corresponding parameters with the 428XL seismograph of the French Sercel company, the instrument in performance has reached the advanced level of overseas equipment.

  20. Fast, high-fidelity readout of multiple qubits

    NASA Astrophysics Data System (ADS)

    Bronn, N. T.; Abdo, B.; Inoue, K.; Lekuch, S.; Córcoles, A. D.; Hertzberg, J. B.; Takita, M.; Bishop, L. S.; Gambetta, J. M.; Chow, J. M.

    2017-05-01

    Quantum computing requires a delicate balance between coupling quantum systems to external instruments for control and readout, while providing enough isolation from sources of decoherence. Circuit quantum electrodynamics has been a successful method for protecting superconducting qubits, while maintaining the ability to perform readout [1, 2]. Here, we discuss improvements to this method that allow for fast, high-fidelity readout. Specifically, the integration of a Purcell filter, which allows us to increase the resonator bandwidth for fast readout, the incorporation of a Josephson parametric converter, which enables us to perform high-fidelity readout by amplifying the readout signal while adding the minimum amount of noise required by quantum mechanics, and custom control electronics, which provide us with the capability of fast decision and control.

  1. UFTI: the 0.8 - 2.5 μm fast track imager for the UK infrared telescope

    NASA Astrophysics Data System (ADS)

    Roche, Patrick F.; Lucas, Philip W.; Mackay, Craig D.; Ettedgui-Atad, Eli; Hastings, Peter R.; Bridger, Alan; Rees, Nicholas P.; Leggett, Sandy K.; Davis, Chris; Holmes, Alan R.; Handford, Tony

    2003-03-01

    In 1996, it was proposed to build a near-infrared imager for the 3.8-m UK Infrared Telescope in Hawaii, to exploit the 1024 pixel format detectors that were then becoming available. In order to achieve a fast delivery, the instrument was kept simple and existing designs were reused or modified where possible. UFTI was delivered within 2.5 years of the project start. The instrument is based around a 1k Rockwell Hawaii detector and a LSR Astrocam controller and uses the new Mauna Kea optimized J,H,K filter set along with I and Z broad-band filters and several narrow-band line filters. The instrument is cooled by a CTI cry-cooler, while the mechanisms are operated by cold, internal, Bergelahr stepping motors. On UKIRT it can be coupled to a Fabry-Perot etalon for tunable narrow-band imaging at K, or a waveplate for imaging polarimetry through 1-2.5 μm the cold analyzer is a Barium Borate Wollaston prism. UFTI was designed to take full advantage of the good image quality delivered by UKIRT on conclusion of the upgrades program, and has a fine scale of 0.09 arcsec/pixel. It is used within the UKIRT observatory environment and was the first instrument integrated into ORAC, the Observatory Reduction and Acquisition Control System. Results obtained during instrument characterization in the lab and over the last 3 years on UKIRT are presented, along with performance figures. UFTI has now been used on UKIRT for several hundred nights, and aspects of instrument performance are discussed.

  2. Experience with advanced instrumentation in a hot section cascade

    NASA Technical Reports Server (NTRS)

    Yeh, Frederick C.; Gladden, Herbert J.

    1989-01-01

    The Lewis Research Center gas turbine Hot Section Test Facility was developed to provide a real engine environment with known boundary conditions for the aerothermal performance evaluation and verification of computer design codes. This verification process requires experimental measurements in a hostile environment. The research instruments used in this facility are presented, and their characteristics and how they perform in this environment are discussed. The research instrumentation consisted of conventional pressure and temperature sensors, as well as thin-film thermocouples and heat flux gages. The hot gas temperature was measured by an aspirated temperature probe and by a dual-element, fast-response temperature probe. The data acquisition mode was both steady state and time dependent. These experiments were conducted over a wide range of gas Reynolds numbers, exit gas Mach numbers, and heat flux levels. This facility was capable of testing at temperatures up to 1600 K, and at pressures up to 18 atm. These corresponded to an airfoil exit Reynolds number range of 0.5 x 10(6) to 2.5 x 10(6) based on the airfoil chord of 5.55 cm. The results characterize the performance capability and the durability of the instrumentation. The challenge of making measurements in hostile environments is also discussed. The instruments exhibited more than adequate durability to achieve the measurement profile. About 70 percent of the thin-film thermocouples and the dual-element temperature probe survived several hundred thermal cycles and more than 35 hr at gas temperatures up to 1600 K. Within the experimental uncertainty, the steady-state and transient heat flux measurements were comparable and consistent over the range of Reynolds numbers tested.

  3. Experience with advanced instrumentation in a hot section cascade

    NASA Astrophysics Data System (ADS)

    Yeh, Frederick C.; Gladden, Herbert J.

    The Lewis Research Center gas turbine Hot Section Test Facility was developed to provide a real engine environment with known boundary conditions for the aerothermal performance evaluation and verification of computer design codes. This verification process requires experimental measurements in a hostile environment. The research instruments used in this facility are presented, and their characteristics and how they perform in this environment are discussed. The research instrumentation consisted of conventional pressure and temperature sensors, as well as thin-film thermocouples and heat flux gages. The hot gas temperature was measured by an aspirated temperature probe and by a dual-element, fast-response temperature probe. The data acquisition mode was both steady state and time dependent. These experiments were conducted over a wide range of gas Reynolds numbers, exit gas Mach numbers, and heat flux levels. This facility was capable of testing at temperatures up to 1600 K, and at pressures up to 18 atm. These corresponded to an airfoil exit Reynolds number range of 0.5 x 10(6) to 2.5 x 10(6) based on the airfoil chord of 5.55 cm. The results characterize the performance capability and the durability of the instrumentation. The challenge of making measurements in hostile environments is also discussed. The instruments exhibited more than adequate durability to achieve the measurement profile. About 70 percent of the thin-film thermocouples and the dual-element temperature probe survived several hundred thermal cycles and more than 35 hr at gas temperatures up to 1600 K. Within the experimental uncertainty, the steady-state and transient heat flux measurements were comparable and consistent over the range of Reynolds numbers tested.

  4. Coast Guard Cutter Procurement: Background and Issues for Congress

    DTIC Science & Technology

    2016-04-04

    and 58 Fast Response Cutters (FRCs) as replacements for 90 aging Coast Guard cutters and patrol craft. The Coast Guard’s proposed FY2017 budget...Offshore Patrol Cutter (Generic Conceptual Rendering) ................................................. 5 Figure 3. Fast Response Cutter...National Security Cutters (NSCs), 25 Offshore Patrol Cutters (OPCs), and 58 Fast Response Cutters (FRCs). These 91 planned cutters are intended as

  5. sCMOS detector for imaging VNIR spectrometry

    NASA Astrophysics Data System (ADS)

    Eckardt, Andreas; Reulke, Ralf; Schwarzer, Horst; Venus, Holger; Neumann, Christian

    2013-09-01

    The facility Optical Information Systems (OS) at the Robotics and Mechatronics Center of the German Aerospace Center (DLR) has more than 30 years of experience with high-resolution imaging technology. This paper shows the scientific results of the institute of leading edge instruments and focal plane designs for EnMAP VIS/NIR spectrograph. EnMAP (Environmental Mapping and Analysis Program) is one of the selected proposals for the national German Space Program. The EnMAP project includes the technological design of the hyper spectral space borne instrument and the algorithms development of the classification. The EnMAP project is a joint response of German Earth observation research institutions, value-added resellers and the German space industry like Kayser-Threde GmbH (KT) and others to the increasing demand on information about the status of our environment. The Geo Forschungs Zentrum (GFZ) Potsdam is the Principal Investigator of EnMAP. DLR OS and KT were driving the technology of new detectors and the FPA design for this project, new manufacturing accuracy and on-chip processing capability in order to keep pace with the ambitious scientific and user requirements. In combination with the engineering research, the current generations of space borne sensor systems are focusing on VIS/NIR high spectral resolution to meet the requirements on earth and planetary observation systems. The combination of large swath and high spectral resolution with intelligent synchronization control, fast-readout ADC chains and new focal-plane concepts open the door to new remote-sensing and smart deep space instruments. The paper gives an overview over the detector verification program at DLR on FPA level, new control possibilities for sCMOS detectors in global shutter mode and key parameters like PRNU, DSNU, MTF, SNR, Linearity, Spectral Response, Quantum Efficiency, Flatness and Radiation Tolerance will be discussed in detail.

  6. Fast Food Consumption and Food Prices: Evidence from Panel Data on 5th and 8th Grade Children

    PubMed Central

    Khan, Tamkeen; Powell, Lisa M.; Wada, Roy

    2012-01-01

    Fast food consumption is a dietary factor associated with higher prevalence of childhood obesity in the United States. The association between food prices and consumption of fast food among 5th and 8th graders was examined using individual-level random effects models utilizing consumption data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99 (ECLS-K), price data from American Chamber of Commerce Researchers Association (ACCRA), and contextual outlet density data from Dun and Bradstreet (D&B). The results found that contextual factors including the price of fast food, median household income, and fast food restaurant outlet densities were significantly associated with fast food consumption patterns among this age group. Overall, a 10% increase in the price of fast food was associated with 5.7% lower frequency of weekly fast food consumption. These results suggest that public health policy pricing instruments such as taxes may be effective in reducing consumption of energy-dense foods and possibly reducing the prevalence of overweight and obesity among US children and young adolescents. PMID:22292115

  7. Fast food consumption and food prices: evidence from panel data on 5th and 8th grade children.

    PubMed

    Khan, Tamkeen; Powell, Lisa M; Wada, Roy

    2012-01-01

    Fast food consumption is a dietary factor associated with higher prevalence of childhood obesity in the United States. The association between food prices and consumption of fast food among 5th and 8th graders was examined using individual-level random effects models utilizing consumption data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99 (ECLS-K), price data from American Chamber of Commerce Researchers Association (ACCRA), and contextual outlet density data from Dun and Bradstreet (D&B). The results found that contextual factors including the price of fast food, median household income, and fast food restaurant outlet densities were significantly associated with fast food consumption patterns among this age group. Overall, a 10% increase in the price of fast food was associated with 5.7% lower frequency of weekly fast food consumption. These results suggest that public health policy pricing instruments such as taxes may be effective in reducing consumption of energy-dense foods and possibly reducing the prevalence of overweight and obesity among US children and young adolescents.

  8. Time-resolved detection of aromatic compounds on planetary surfaces by ultraviolet laser induced fluorescence and Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Eshelman, E.; Daly, M. G.; Slater, G.; Cloutis, E.

    2015-12-01

    Raman spectroscopic instruments are highly capable in the search for organics on Mars due to the potential to perform rapid and nondestructive measurements on unprepared samples. Upcoming and future Raman instruments are likely to also incorporate laser-induced fluorescence (LIF) capabilities, which can be added for modest cost and complexity. We demonstrate that it is possible to obtain sub-ns fluorescence lifetime measurements of Mars-relevant organics and minerals if a fast time-gating capability is used with an intensified detector and a short ultraviolet laser pulse. This serves a primary purpose of discriminating mineral from short-lived (less than 10 ns) organic fluorescence, considered a potential biosignature. Additionally, lifetime measurements may assist in determining if more than one fluorescing species is present and provide information concerning the molecular structure as well as the local environment. Fast time-gating is also useful at longer visible or near-IR wavelengths, as this approach increases the sensitivity of the instrument to organic material by removing the majority of the fluorescence background from the Raman signal and reducing the effect of ambient light.

  9. Active Interrogation for Spent Fuel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Swinhoe, Martyn Thomas; Dougan, Arden

    2015-11-05

    The DDA instrument for nuclear safeguards is a fast, non-destructive assay, active neutron interrogation technique using an external 14 MeV DT neutron generator for characterization and verification of spent nuclear fuel assemblies.

  10. Observations of barium ion jets in the magnetosphere using Doppler imaging systems and very sensitive imaging systems using imaging photon detectors

    NASA Technical Reports Server (NTRS)

    Rees, D.; Conboy, J.; Heinz, W.; Heppner, J. P.

    1985-01-01

    Observations of four shaped charge releases from rockets launched from Alaska are described. Results demonstrate that imaging and Doppler imaging instruments, based on exploiting the imaging photon detector, provide additional insight into the motion and development of low intensity targets such as the fast ion jets produced by shaped charge releases. It is possible to trace the motion of fast ion jets to very great distances, of the order of 50,000 km, outward along the Earth's magnetic field, when the conditions are suitable for the outward (upward) motion and/or acceleration of such ion jets. It is shown that ion jets, which fade below the lower sensitivity threshold of previous instruments, do not always disappear. There is no evidence of an abrupt field-aligned shear-type acceleration.

  11. Matrix form for the instrument line shape of Fourier-transform spectrometers yielding a fast integration algorithm to theoretical spectra.

    PubMed

    Desbiens, Raphaël; Tremblay, Pierre; Genest, Jérôme; Bouchard, Jean-Pierre

    2006-01-20

    The instrument line shape (ILS) of a Fourier-transform spectrometer is expressed in a matrix form. For all line shape effects that scale with wavenumber, the ILS matrix is shown to be transposed in the spectral and interferogram domains. The novel representation of the ILS matrix in the interferogram domain yields an insightful physical interpretation of the underlying process producing self-apodization. Working in the interferogram domain circumvents the problem of taking into account the effects of finite optical path difference and permits a proper discretization of the equations. A fast algorithm in O(N log2 N), based on the fractional Fourier transform, is introduced that permits the application of a constant resolving power line shape to theoretical spectra or forward models. The ILS integration formalism is validated with experimental data.

  12. Performance and applications of a hypertemporal hyperspectral Fourier-transform infrared spectroradiometer

    NASA Astrophysics Data System (ADS)

    King, Bruce H.; Ellis, Thomas; Old, Tom E.

    2009-05-01

    A fast-scanning, high-resolution FTIR spectroradiometer has been designed and built for use in remote sensing, stand-off detection, and spectral-temporal characterization of fast, energetic infrared events. The instrument design uses a Michelson-type interferometer with a rotary modulator which is capable of continuous measurement of infrared spectra at a rate of 1000 scans per second with 4 cm-1 resolution in the 2 - 25 micron spectral range. Sensitivity, spectral accuracy, and radiometric precision are discussed along with specific design parameters. This instrument can be used for passive sensing as a stand-alone sensor, or for active sensing as a receiver when used in conjunction with a highenergy excitation source such as a laser. Applications include muzzle flash signature measurement, ordnance detonation characterization, missile plume identification, and rocket motor combustion diagnostics.

  13. Assessing the potential effectiveness of food and beverage taxes and subsidies for improving public health: a systematic review of prices, demand and body weight outcomes.

    PubMed

    Powell, L M; Chriqui, J F; Khan, T; Wada, R; Chaloupka, F J

    2013-02-01

    Taxes and subsidies are increasingly being considered as potential policy instruments to incentivize consumers to improve their food and beverage consumption patterns and related health outcomes. This study provided a systematic review of recent U.S. studies on the price elasticity of demand for sugar-sweetened beverages (SSBs), fast food, and fruits and vegetables, as well as the direct associations of prices/taxes with body weight outcomes. Based on the recent literature, the price elasticity of demand for SSBs, fast food, fruits and vegetables was estimated to be -1.21, -0.52, -0.49 and -0.48, respectively. The studies that linked soda taxes to weight outcomes showed minimal impacts on weight; however, they were based on existing state-level sales taxes that were relatively low. Higher fast-food prices were associated with lower weight outcomes particularly among adolescents, suggesting that raising prices would potentially impact weight outcomes. Lower fruit and vegetable prices were generally found to be associated with lower body weight outcomes among both low-income children and adults, suggesting that subsidies that would reduce the cost of fruits and vegetables for lower-socioeconomic populations may be effective in reducing obesity. Pricing instruments should continue to be considered and evaluated as potential policy instruments to address public health risks. © 2012 The Authors. obesity reviews © 2012 International Association for the Study of Obesity.

  14. Metabolic adaptation to intermittent fasting is independent of peroxisome proliferator-activated receptor alpha.

    PubMed

    Li, Guolin; Brocker, Chad N; Yan, Tingting; Xie, Cen; Krausz, Kristopher W; Xiang, Rong; Gonzalez, Frank J

    2018-01-01

    Peroxisome proliferator-activated receptor alpha (PPARA) is a major regulator of fatty acid oxidation and severe hepatic steatosis occurs during acute fasting in Ppara-null mice. Thus, PPARA is considered an important mediator of the fasting response; however, its role in other fasting regiments such as every-other-day fasting (EODF) has not been investigated. Mice were pre-conditioned using either a diet containing the potent PPARA agonist Wy-14643 or an EODF regimen prior to acute fasting. Ppara-null mice were used to assess the contribution of PPARA activation during the metabolic response to EODF. Livers were collected for histological, biochemical, qRT-PCR, and Western blot analysis. Acute fasting activated PPARA and led to steatosis, whereas EODF protected against fasting-induced hepatic steatosis without affecting PPARA signaling. In contrast, pretreatment with Wy-14,643 did activate PPARA signaling but did not ameliorate acute fasting-induced steatosis and unexpectedly promoted liver injury. Ppara ablation exacerbated acute fasting-induced hypoglycemia, hepatic steatosis, and liver injury in mice, whereas these detrimental effects were absent in response to EODF, which promoted PPARA-independent fatty acid metabolism and normalized serum lipids. These findings indicate that PPARA activation prior to acute fasting cannot ameliorate fasting-induced hepatic steatosis, whereas EODF induced metabolic adaptations to protect against fasting-induced steatosis without altering PPARA signaling. Therefore, PPARA activation does not mediate the metabolic adaptation to fasting, at least in preventing acute fasting-induced steatosis. Published by Elsevier GmbH.

  15. The role of adrenal hormones in the response of glutamine synthetase to fasting in adult and old rats.

    PubMed

    Mezzarobba, V; Torrent, A; Leydier, I; Alles, S; Brajon, B; Mignon, M; Attaix, D; Meynial-Denis, D

    2003-12-01

    During fasting, skeletal muscle exports increased amounts of glutamine (Gln) while increasing the production of this amino acid by glutamine synthetase (GS) in order to maintain the intramuscular Gln pool. Glucocorticoid hormones are believed to be the principal mediators of GS induction during stress conditions. The aim of this study was to evaluate (1) the effect of fasting on GS activity and expression in skeletal muscle during aging and consequently, (2) the role of glucocorticoids in fasting-induced GS activity. Male Wistar rats (6-, 22-month old) were fasted for 5 days and both the activity and expression of GS were measured in tibialis anterior muscle. To better demonstrate the role of glucocorticoids in the response of GS to fasting, we suppressed their action by RU38486 administration (a potent glucocorticoid antagonist) and their production by adrenalectomy in fed and fasted rats. An increase in fasting-induced GS activity was observed in skeletal muscles from both adult and aged rats. Adrenalectomy, but surprisingly not RU38486, suppressed the fasting-induced increase in GS activity and expression. The data clearly show that the GS responsiveness to fasting was not modified by aging in skeletal muscle.

  16. Laser Light Scattering Diagnostic for Measurement of Flow Velocity in Vicinity of Propagating Shock Waves

    NASA Technical Reports Server (NTRS)

    Seasholtz, Richard G.; Buggele, Alvin E.

    2002-01-01

    A laser light scattering diagnostic for measurement of dynamic flow velocity at a point is described. The instrument is being developed for use in the study of propagating shock waves and detonation waves in pulse detonation engines under development at the NASA Glenn Research Center (GRC). The approach uses a Fabry-Perot interferometer to measure the Doppler shift of laser light scattered from small (submicron) particles in the flow. The high-speed detection system required to resolve the transient response as a shock wave crosses the probe volume uses fast response photodetectors, and a PC based data acquisition system. Preliminary results of measurements made in the GRC Mach 4, 10 by 25 cm supersonic wind tunnel are presented. Spontaneous condensation of water vapor in the flow is used as seed. The tunnel is supplied with continuous air flow at up to 45 psia and the flow is exhausted into the GRC laboratory-wide altitude exhaust system at pressures down to 0.3 psia.

  17. Comparison of Two Methodologies for Calibrating Satellite Instruments in the Visible and Near Infrared

    NASA Technical Reports Server (NTRS)

    Barnes, Robert A.; Brown, Steven W.; Lykke, Keith R.; Guenther, Bruce; Xiong, Xiaoxiong (Jack); Butler, James J.

    2010-01-01

    Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance response in a two-step method. In the first step, the spectral response of the instrument is determined using a nearly monochromatic light source, such a lamp-illuminated monochromator. Such sources only provide a relative spectral response (RSR) for the instrument, since they do not act as calibrated sources of light nor do they typically fill the field-of-view of the instrument. In the second step, the instrument views a calibrated source of broadband light, such as lamp-illuminated integrating sphere. In the traditional method, the RSR and the sphere spectral radiance are combined and, with the instrument's response, determine the absolute spectral radiance responsivity of the instrument. More recently, an absolute calibration system using widely tunable monochromatic laser systems has been developed, Using these sources, the absolute spectral responsivity (ASR) of an instrument can be determined on a wavelength-hy-wavelength basis. From these monochromatic ASRs. the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as integrating spheres. Here we describe the laser-based calibration and the traditional broad-band source-based calibration of the NPP VIIRS sensor, and compare the derived calibration coefficients for the instrument. Finally, we evaluate the impact of the new calibration approach on the on-orbit performance of the sensor.

  18. Hardware solution for continuous time-resolved burst detection of single molecules in flow

    NASA Astrophysics Data System (ADS)

    Wahl, Michael; Erdmann, Rainer; Lauritsen, Kristian; Rahn, Hans-Juergen

    1998-04-01

    Time Correlated Single Photon Counting (TCSPC) is a valuable tool for Single Molecule Detection (SMD). However, existing TCSPC systems did not support continuous data collection and processing as is desirable for applications such as SMD for e.g. DNA-sequencing in a liquid flow. First attempts at using existing instrumentation in this kind of operation mode required additional routing hardware to switch between several memory banks and were not truly continuous. We have designed a hard- and software system to perform continuous real-time TCSPC based upon a modern solid state Time to Digital Converter (TDC). Short dead times of the fully digital TDC design combined with fast Field Programmable Gay Array logic permit a continuous data throughput as high as 3 Mcounts/sec. The histogramming time may be set as short as 100 microsecond(s) . Every histogram or every single fluorescence photon can be real-time tagged at 200 ns resolution in addition to recording its arrival time relative to the excitation pulse. Continuous switching between memory banks permits concurrent histogramming and data read-out. The instrument provides a time resolution of 60 ps and up to 4096 histogram channels. The overall instrument response function in combination with a low cost picosecond diode laser and an inexpensive photomultiplier tube was found to be 180 ps and well sufficient to measure sub-nanosecond fluorescence lifetimes.

  19. Cosmic Ray Energetics and Mass (CREAM)

    NASA Technical Reports Server (NTRS)

    Coutu, Stephane

    2005-01-01

    The CREAM instrument was flown on a Long Duration Balloon in Antarctica in December 2004 and January 2005, achieving a flight duration record of nearly 42 days. It detected and recorded cosmic ray primary particles ranging in type from hydrogen to iron nuclei and in energy from 1 TeV to several hundred TeV. With the data collected we will have the world's best measurement of the energy spectra and mass composition of nuclei in the primary cosmic ray flux at these energies, close to the astrophysical knee . The instrument utilized a thin calorimeter, a transition radiation detector and a timing charge detector, which also provided time-of-flight information. The responsibilities of our group have been with the timing charge detector (TCD), and with the data acquisition electronics and ground station support equipment. The TCD utilized fast scintillators to measure the charge of the primary cosmic ray before any interactions could take place within the calorimeter. The data acquisition electronics handled the output of the various detectors, in a fashion fully integrated with the payload bus. A space-qualified flight computer controlled the acquisition, and was used for preliminary trigger information processing and decision making. Ground support equipment was used to monitor the health of the payload, acquire and archive the data transmitted to the ground, and to provide real-time control of the instrument in flight.

  20. Reply to Comment: 'A novel method for fast and robust estimation of fluorescence decay dynamics using constrained least-square deconvolution with Laguerre expansion'.

    PubMed

    Ma, Dinglong; Liu, Jing; Qi, Jinyi; Marcu, Laura

    2017-02-21

    In this response we underscore that the instrumentation described in the original publication (Liu et al 2012 Phys. Med. Biol. 57 843-65) was based on pulse-sampling technique, while the comment by Zhang et al is based on the assumption that a time-correlated single photon counting (TCSPC) instrumentation was used. Therefore the arguments made in the comment are not applicable to the noise model reported by Liu et al. As reported in the literature (Lakowicz 2006 Principles of Fluorescence Spectroscopy (New York: Springer)), while in the TCSPC the experimental noise can be estimated from Poisson statistics, such an assumption is not valid for pulse-sampling (transient recording) techniques. To further clarify this aspect, we present here a comprehensive noise model describing the signal and noise propagation of the pulse sampling time-resolved fluorescence detection. Experimental data recorded in various conditions are analyzed as a case study to demonstrate the noise model of our instrumental system. In addition, regarding the statement of correcting equation (3) in Liu et al (2012 Phys. Med. Biol. 57 843-65), the notation of discrete time Laguerre function in the original publication was clear and consistent with literature conventions (Marmarelis 1993 Ann. Biomed. Eng. 21 573-89, Westwick and Kearney 2003 Identification of Nonlinear Physiological Systems (Hoboken, NJ: Wiley)). Thus, it does not require revision.

  1. Reply to Comment: ‘A novel method for fast and robust estimation of fluorescence decay dynamics using constrained least-square deconvolution with Laguerre expansion’

    NASA Astrophysics Data System (ADS)

    Ma, Dinglong; Liu, Jing; Qi, Jinyi; Marcu, Laura

    2017-02-01

    In this response we underscore that the instrumentation described in the original publication (Liu et al 2012 Phys. Med. Biol. 57 843-65) was based on pulse-sampling technique, while the comment by Zhang et al is based on the assumption that a time-correlated single photon counting (TCSPC) instrumentation was used. Therefore the arguments made in the comment are not applicable to the noise model reported by Liu et al. As reported in the literature (Lakowicz 2006 Principles of Fluorescence Spectroscopy (New York: Springer)), while in the TCSPC the experimental noise can be estimated from Poisson statistics, such an assumption is not valid for pulse-sampling (transient recording) techniques. To further clarify this aspect, we present here a comprehensive noise model describing the signal and noise propagation of the pulse sampling time-resolved fluorescence detection. Experimental data recorded in various conditions are analyzed as a case study to demonstrate the noise model of our instrumental system. In addition, regarding the statement of correcting equation (3) in Liu et al (2012 Phys. Med. Biol. 57 843-65), the notation of discrete time Laguerre function in the original publication was clear and consistent with literature conventions (Marmarelis 1993 Ann. Biomed. Eng. 21 573-89, Westwick and Kearney 2003 Identification of Nonlinear Physiological Systems (Hoboken, NJ: Wiley)). Thus, it does not require revision.

  2. A flexible, on-line magnetic spectrometer for ultra-intense laser produced fast electron measurement

    NASA Astrophysics Data System (ADS)

    Ge, Xulei; Yuan, Xiaohui; Yang, Su; Deng, Yanqing; Wei, Wenqing; Fang, Yuan; Gao, Jian; Liu, Feng; Chen, Min; Zhao, Li; Ma, Yanyun; Sheng, Zhengming; Zhang, Jie

    2018-04-01

    We have developed an on-line magnetic spectrometer to measure energy distributions of fast electrons generated from ultra-intense laser-solid interactions. The spectrometer consists of a sheet of plastic scintillator, a bundle of non-scintillating plastic fibers, and an sCMOS camera recording system. The design advantages include on-line capturing ability, versatility of detection arrangement, and resistance to harsh in-chamber environment. The validity of the instrument was tested experimentally. This spectrometer can be applied to the characterization of fast electron source for understanding fundamental laser-plasma interaction physics and to the optimization of high-repetition-rate laser-driven applications.

  3. CO Component Estimation Based on the Independent Component Analysis

    NASA Astrophysics Data System (ADS)

    Ichiki, Kiyotomo; Kaji, Ryohei; Yamamoto, Hiroaki; Takeuchi, Tsutomu T.; Fukui, Yasuo

    2014-01-01

    Fast Independent Component Analysis (FastICA) is a component separation algorithm based on the levels of non-Gaussianity. Here we apply FastICA to the component separation problem of the microwave background, including carbon monoxide (CO) line emissions that are found to contaminate the PLANCK High Frequency Instrument (HFI) data. Specifically, we prepare 100 GHz, 143 GHz, and 217 GHz mock microwave sky maps, which include galactic thermal dust, NANTEN CO line, and the cosmic microwave background (CMB) emissions, and then estimate the independent components based on the kurtosis. We find that FastICA can successfully estimate the CO component as the first independent component in our deflection algorithm because its distribution has the largest degree of non-Gaussianity among the components. Thus, FastICA can be a promising technique to extract CO-like components without prior assumptions about their distributions and frequency dependences.

  4. CO component estimation based on the independent component analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ichiki, Kiyotomo; Kaji, Ryohei; Yamamoto, Hiroaki

    2014-01-01

    Fast Independent Component Analysis (FastICA) is a component separation algorithm based on the levels of non-Gaussianity. Here we apply FastICA to the component separation problem of the microwave background, including carbon monoxide (CO) line emissions that are found to contaminate the PLANCK High Frequency Instrument (HFI) data. Specifically, we prepare 100 GHz, 143 GHz, and 217 GHz mock microwave sky maps, which include galactic thermal dust, NANTEN CO line, and the cosmic microwave background (CMB) emissions, and then estimate the independent components based on the kurtosis. We find that FastICA can successfully estimate the CO component as the first independentmore » component in our deflection algorithm because its distribution has the largest degree of non-Gaussianity among the components. Thus, FastICA can be a promising technique to extract CO-like components without prior assumptions about their distributions and frequency dependences.« less

  5. Fast-ion Dα spectrum diagnostic in the EAST

    NASA Astrophysics Data System (ADS)

    Hou, Y. M.; Wu, C. R.; Huang, J.; Heidbrink, W. W.; von Hellermann, M. G.; Xu, Z.; Jin, Z.; Chang, J. F.; Zhu, Y. B.; Gao, W.; Chen, Y. J.; Lyu, B.; Hu, R. J.; Zhang, P. F.; Zhang, L.; Gao, W.; Wu, Z. W.; Yu, Y.; Ye, M. Y.

    2016-11-01

    In toroidal magnetic fusion devices, fast-ion D-alpha diagnostic (FIDA) is a powerful method to study the fast-ion feature. The fast-ion characteristics can be inferred from the Doppler shifted spectrum of Dα light according to charge exchange recombination process between fast ions and probe beam. Since conceptual design presented in the last HTPD conference, significant progress has been made to apply FIDA systems on the Experimental Advanced Superconducting Tokamak (EAST). Both co-current and counter-current neutral beam injectors are available, and each can deliver 2-4 MW beam power with 50-80 keV beam energy. Presently, two sets of high throughput spectrometer systems have been installed on EAST, allowing to capture passing and trapped fast-ion characteristics simultaneously, using Kaiser HoloSpec transmission grating spectrometer and Bunkoukeiki FLP-200 volume phase holographic spectrometer coupled with Princeton Instruments ProEM 1024B eXcelon and Andor DU-888 iXon3 1024 CCD camera, respectively. This paper will present the details of the hardware descriptions and experimental spectrum.

  6. Laser Induced Breakdown Spectroscopy for Elemental Analysis in Environmental, Cultural Heritage and Space Applications: A Review of Methods and Results

    PubMed Central

    Gaudiuso, Rosalba; Dell’Aglio, Marcella; De Pascale, Olga; Senesi, Giorgio S.; De Giacomo, Alessandro

    2010-01-01

    Analytical applications of Laser Induced Breakdown Spectroscopy (LIBS), namely optical emission spectroscopy of laser-induced plasmas, have been constantly growing thanks to its intrinsic conceptual simplicity and versatility. Qualitative and quantitative analysis can be performed by LIBS both by drawing calibration lines and by using calibration-free methods and some of its features, so as fast multi-elemental response, micro-destructiveness, instrumentation portability, have rendered it particularly suitable for analytical applications in the field of environmental science, space exploration and cultural heritage. This review reports and discusses LIBS achievements in these areas and results obtained for soils and aqueous samples, meteorites and terrestrial samples simulating extraterrestrial planets, and cultural heritage samples, including buildings and objects of various kinds. PMID:22163611

  7. Laser induced breakdown spectroscopy for elemental analysis in environmental, cultural heritage and space applications: a review of methods and results.

    PubMed

    Gaudiuso, Rosalba; Dell'Aglio, Marcella; De Pascale, Olga; Senesi, Giorgio S; De Giacomo, Alessandro

    2010-01-01

    Analytical applications of Laser Induced Breakdown Spectroscopy (LIBS), namely optical emission spectroscopy of laser-induced plasmas, have been constantly growing thanks to its intrinsic conceptual simplicity and versatility. Qualitative and quantitative analysis can be performed by LIBS both by drawing calibration lines and by using calibration-free methods and some of its features, so as fast multi-elemental response, micro-destructiveness, instrumentation portability, have rendered it particularly suitable for analytical applications in the field of environmental science, space exploration and cultural heritage. This review reports and discusses LIBS achievements in these areas and results obtained for soils and aqueous samples, meteorites and terrestrial samples simulating extraterrestrial planets, and cultural heritage samples, including buildings and objects of various kinds.

  8. High-Resolution Strain Analysis of the Human Heart with Fast-DENSE

    NASA Astrophysics Data System (ADS)

    Aletras, Anthony H.; Balaban, Robert S.; Wen, Han

    1999-09-01

    Single breath-hold displacement data from the human heart were acquired with fast-DENSE (fast displacement encoding with stimulated echoes) during systolic contraction at 2.5 × 2.5 mm in-plane resolution. Encoding strengths of 0.86-1.60 mm/π were utilized in order to extend the dynamic range of the phase measurements and minimize effects of physiologic and instrument noise. The noise level in strain measurements for both contraction and dilation corresponded to a strain value of 2.8%. In the human heart, strain analysis has sufficient resolution to reveal transmural variation across the left ventricular wall. Data processing required minimal user intervention and provided a rapid quantitative feedback. The intrinsic temporal integration of fast-DENSE achieves high accuracy at the expense of temporal resolution.

  9. Increased sensitivity of thyroid hormone-mediated signaling despite prolonged fasting.

    PubMed

    Martinez, Bridget; Scheibner, Michael; Soñanez-Organis, José G; Jaques, John T; Crocker, Daniel E; Ortiz, Rudy M

    2017-10-01

    Thyroid hormones (TH) can increase cellular metabolism. Food deprivation in mammals is typically associated with reduced thyroid gland responsiveness, in an effort to suppress cellular metabolism and abate starvation. However, in prolonged-fasted, elephant seal pups, cellular TH-mediated proteins are up-regulated and TH levels are maintained with fasting duration. The function and contribution of the thyroid gland to this apparent paradox is unknown and physiologically perplexing. Here we show that the thyroid gland remains responsive during prolonged food deprivation, and that its function and production of TH increase with fasting duration in elephant seals. We discovered that our modeled plasma TH data in response to exogenous thyroid stimulating hormone predicted cellular signaling, which was corroborated independently by the enzyme expression data. The data suggest that the regulation and function of the thyroid gland in the northern elephant seal is atypical for a fasted animal, and can be better described as, "adaptive fasting". Furthermore, the modeling data help substantiate the in vivo responses measured, providing unique insight on hormone clearance, production rates, and thyroid gland responsiveness. Because these unique endocrine responses occur simultaneously with a nearly strict reliance on the oxidation of lipid, these findings provide an intriguing model to better understand the TH-mediated reliance on lipid metabolism that is not otherwise present in morbidly obese humans. When coupled with cellular, tissue-specific responses, these data provide a more integrated assessment of thyroidal status that can be extrapolated for many fasting/food deprived mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. A remotely triggered fast neutron detection instrument based on a plastic organic scintillator

    NASA Astrophysics Data System (ADS)

    Jones, A. R.; Aspinall, M. D.; Joyce, M. J.

    2018-02-01

    A detector system for the characterization of radiation fields of both fast neutrons and γ rays is described comprising of a gated photomultiplier tube (PMT), an EJ299-33 solid organic scintillator detector, and an external trigger circuit. The objective of this development was to conceive a means by which the PMT in such a system can be actuated remotely during the high-intensity bursts of pulsed γ-ray contamination that can arise during active interrogation procedures. The system is used to detect neutrons and γ rays using established pulse-shape discrimination (PSD) techniques. The gating circuit enables the PMT to be switched off remotely. This is compatible with use during intense radiation transients to avoid saturation and the disruption of the operation of the PMT during the burst. Data are presented in the form of pulse-height spectra and PSD scatter plots for the system triggered with a strobed light source. These confirm that the gain of the system and the throughput for both triggered and un-triggered scenarios are as expected, given the duty cycle of the stimulating radiation. This demonstrates that the triggering function does not perturb the system response of the detector.

  11. A remotely triggered fast neutron detection instrument based on a plastic organic scintillator.

    PubMed

    Jones, A R; Aspinall, M D; Joyce, M J

    2018-02-01

    A detector system for the characterization of radiation fields of both fast neutrons and γ rays is described comprising of a gated photomultiplier tube (PMT), an EJ299-33 solid organic scintillator detector, and an external trigger circuit. The objective of this development was to conceive a means by which the PMT in such a system can be actuated remotely during the high-intensity bursts of pulsed γ-ray contamination that can arise during active interrogation procedures. The system is used to detect neutrons and γ rays using established pulse-shape discrimination (PSD) techniques. The gating circuit enables the PMT to be switched off remotely. This is compatible with use during intense radiation transients to avoid saturation and the disruption of the operation of the PMT during the burst. Data are presented in the form of pulse-height spectra and PSD scatter plots for the system triggered with a strobed light source. These confirm that the gain of the system and the throughput for both triggered and un-triggered scenarios are as expected, given the duty cycle of the stimulating radiation. This demonstrates that the triggering function does not perturb the system response of the detector.

  12. Fast-response cup anemometer features cosine response

    NASA Technical Reports Server (NTRS)

    Frenzen, P.

    1968-01-01

    Six-cup, low-inertia anemometer combines high resolution and fast response with a unique ability to sense only the horizontal component of the winds fluctuating rapidly in three dimensions. Cup assemblies are fabricated of expanded polystyrene plastic.

  13. High stability integrated Tri-axial fluxgate sensor with suspended technology

    NASA Astrophysics Data System (ADS)

    Wang, Chen; Teng, Yuntian; Wang, Xiaomei; Fan, Xiaoyong; Wu, Qiong

    2017-04-01

    The relative geomagnetic record of China Geomagnetic Network of China(GNC) has been digitized, network, meanwhile achieving second data acquisition and storage during after 9th five-year and 10th five-year plan upgraded. Currently the relative record in geomagnetic observatories are generally two sets of the same type instrument with parallel observation, which could distinguish the differential between observation instrument failures and environmental interference, and ensure the continuity and integrity of the observation data. Fluxgate magnetometer has become mainstream equipment for relative geomagnetic record because of its low noise, high sensitivity, and fast response. There is a problem about data inconsistency by the same type of instrument in the same station though few years observation data analysis. The researchers have done a lot of experiments and found three main error sources:1. The instrument performances, due to the limitation of manufacturing and assembly process level it is difficult to ensure the orthogonality of the instrument; other performances of scale, zero offset and temperature coefficient; 2. horizontal error, which introduced by the initial installation process due to horizontal adjustment and pillar tilling due to long-term observations; 3.The observation environment, the temperature and humidity, power supply system. The new fluxgate magnetometer uses special nonmagnetic gimbaled (made by beryllium / bronze material) construction for suspension, so the fluxgate sensor is fixed at the suspended platform in order to automatically keep the horizontal level. The advantage of this design is to eliminate horizontal error introduced by the initial installation process due to horizontal adjustment and pillar tilling due to long-term observations. The signal processing circuit board is fixed on the top of the suspended platform with certain distance to ensure the static and dynamic magnetic field produced by circuit board no effect to the sensor, so we could get flexible instrument due to signal attenuation resulting signal transmission cable limited length.

  14. The VoiLA ocean bottom seismic array: First insights into the intermediate depth seismicity distribution in the Lesser Antilles

    NASA Astrophysics Data System (ADS)

    Rietbrock, A.; Harmon, N.; Goes, S. D. B.; Krueger, F.; Bie, L.; Collier, J.; Rychert, C.; Hicks, S. P.; Kendall, J. M.; Henstock, T.

    2017-12-01

    Subduction zones are the most important regions for the exchange of water between the Oceans and the solid Earth. Hydrated oceanic lithosphere is subducted into the deeper Earth and its bound water content is continuously released in a heterogeneous process as temperature and pressure rises with depth. As only small amounts of water can significantly alter the physical properties of materials at depth, water is believed to play a major role in the seismogenesis for both, the shallow megathrust responsible for large destructive earthquakes and the occurrence of Wadati-Benioff zone seismicity at intermediate depth. Up to now most of our observations have been made around the Circum-Pacific subduction were predominantly oceanic lithosphere generated at fast-spreading ridges is being subducted. Contrary, observations of dehydration processes occurring in subducting oceanic lithosphere generated at slow spreading ridges are limited. The Lesser Antilles subduction zone therefore provides the unique opportunity to study the linkage between seismicity and de-hydration reaction for subductiong lithosphere generated at a slow-spreading ridge. Between March 2016 and May 2017 34 Ocean Bottom Broadband Seismometers were deployed along the Lesser Antilles margin in the area 12°-18° N and 63.5°-59.5° W. The network consisted out of 24 DEPAS instruments with 120s Trillium compact sensors provided by the instrument pool of AWI (Germany) and 10 OBSIP instruments with Trillium 240s sensors provided by Scripps Institute of Oceanography (US). All instruments were recovered and only 2 OBSIP instruments did not collect any usable data. The remaining 32 instruments did record continuously all components and no clock timing issues were identified. Preliminary screening of the data shows a low noise level and numerous local/regional earthquakes with M<3 have been detected. We will present the recorded seismicity distribution and earthquake locations based on a refined 1D/2D velocity model.

  15. Direct Detection of C_2H_2 in Air and Human Breath by Cw-Crds

    NASA Astrophysics Data System (ADS)

    Schmidt, Florian M.; Vaittinen, Olavi; Metsälä, Markus; Halonen, Lauri

    2010-06-01

    Continuous wave cavity ring-down spectroscopy (cw-CRDS) is an established cavity-enhanced absorption technique that can provide the necessary sensitivity, selectivity and fast acquisition time for many applications involving the detection of trace species. We present a simple but highly sensitive cw-CRDS spectrometer based on an external cavity diode laser operating in the near-infrared region. This instrument allows us to directly detect acetylene (C_2H_2) mixing ratios in air with a detection limit of 120 parts per trillion by volume (pptv) measuring on a C_2H_2 absorption line at 6565.620 cm-1. Acetylene is a combustion product that is routinely used in environmental monitoring as a marker for anthropogenic emissions. In a recent work, the spectrometer was employed to measure the level of acetylene in indoor and outdoor air in Helsinki. Continuous flow measurements with high time resolution (one minute) revealed strong fluctuations in the acetylene mixing ratio in outdoor air during daytime. Due to its non-invasive nature and fast response time, the analysis of exhaled breath for medical diagnostics is an excellent and straightforward alternative to methods using urine or blood samples. In an ongoing study, the cw-CRDS instrument is used to establish the baseline level of acetylene in the breath of the healthy population. An elevated amount of acetylene in breath could indicate exposure to combustion exhausts or other volatile organic compound (VOC) rich sources. The latest results of this investigation will be presented. F. M. Schmidt, O. Vaittinen, M. Metsälä, P. Kraus and L. Halonen, submitted for publication in Appl. Phys. B.

  16. Very high pressure liquid chromatography using fully porous particles: quantitative analysis of fast gradient separations without post-run times.

    PubMed

    Stankovich, Joseph J; Gritti, Fabrice; Stevenson, Paul G; Beaver, Lois Ann; Guiochon, Georges

    2014-01-10

    Using a column packed with fully porous particles, four methods for controlling the flow rates at which gradient elution runs are conducted in very high pressure liquid chromatography (VHPLC) were tested to determine whether reproducible thermal conditions could be achieved, such that subsequent analyses would proceed at nearly the same initial temperature. In VHPLC high flow rates are achieved, producing fast analyses but requiring high inlet pressures. The combination of high flow rates and high inlet pressures generates local heat, leading to temperature changes in the column. Usually in this case a post-run time is input into the analytical method to allow the return of the column temperature to its initial state. An alternative strategy involves operating the column without a post-run equilibration period and maintaining constant temperature variations for subsequent analysis after conducting one or a few separations to bring the column to a reproducible starting temperature. A liquid chromatography instrument equipped with a pressure controller was used to perform constant pressure and constant flow rate VHPLC separations. Six replicate gradient separations of a nine component mixture consisting of acetophenone, propiophenone, butyrophenone, valerophenone, hexanophenone, heptanophenone, octanophenone, benzophenone, and acetanilide dissolved in water/acetonitrile (65:35, v/v) were performed under various experimental conditions: constant flow rate, two sets of constant pressure, and constant pressure operation with a programmed flow rate. The relative standard deviations of the response factors for all the analytes are lower than 5% across the methods. Programming the flow rate to maintain a fairly constant pressure instead of using instrument controlled constant pressure improves the reproducibility of the retention times by a factor of 5, when plotting the chromatograms in time. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. On the Micrometeorology of the Southern Great Plains. 2: Turbulence Statistics

    NASA Astrophysics Data System (ADS)

    Hicks, Bruce B.; Pendergrass, W. R.; Vogel, C. A.; Keener, R. N.; Leyton, S. M.

    2015-03-01

    Fast-response micrometeorological data obtained from an instrumented 32-m tower at an arid site near Ocotillo, Texas are used to examine the daily time evolution of the lower atmosphere. Correlation coefficients between turbulence properties (fast response wind-speed components and temperature) confirm that over this sparsely vegetated site the effects of convection are observed soon after sunrise, well ahead of the morning transition from stable to unstable stratification. Details of this kind are obscured when results are considered as functions of conventional stability parameters, since such standard analytical methods combine features of the morning and evening transitions into a single presentation. Partial correlation coefficients and semi-partials indicate that the local turbulent kinetic energy is mainly associated with local fluxes of heat and momentum near neutral and in most stable conditions, but decreases substantially during the times of strongest instability (possibly reflecting the scatter introduced by sampling infrequent convective episodes using a single tower). For many of the variables considered here, the standard deviations are about the same as the linear averages, indicating that the distributions are close to log-normal. The present data indicate that if the intent is to address some specific situation then 10 % error bounds on turbulence quantities (e.g. fluxes) correspond to averaging over a distance scale of the order of 10 km and a time scale of about 3 h. As the distance and time scales become smaller, the uncertainties due to factors external to the local surface increase.

  18. A case study in adaptable and reusable infrastructure at the Keck Observatory Archive: VO interfaces, moving targets, and more

    NASA Astrophysics Data System (ADS)

    Berriman, G. Bruce; Cohen, Richard W.; Colson, Andrew; Gelino, Christopher R.; Good, John C.; Kong, Mihseh; Laity, Anastasia C.; Mader, Jeffrey A.; Swain, Melanie A.; Tran, Hien D.; Wang, Shin-Ywan

    2016-08-01

    The Keck Observatory Archive (KOA) (https://koa.ipac.caltech.edu) curates all observations acquired at the W. M. Keck Observatory (WMKO) since it began operations in 1994, including data from eight active instruments and two decommissioned instruments. The archive is a collaboration between WMKO and the NASA Exoplanet Science Institute (NExScI). Since its inception in 2004, the science information system used at KOA has adopted an architectural approach that emphasizes software re-use and adaptability. This paper describes how KOA is currently leveraging and extending open source software components to develop new services and to support delivery of a complete set of instrument metadata, which will enable more sophisticated and extensive queries than currently possible. In August 2015, KOA deployed a program interface to discover public data from all instruments equipped with an imaging mode. The interface complies with version 2 of the Simple Imaging Access Protocol (SIAP), under development by the International Virtual Observatory Alliance (IVOA), which defines a standard mechanism for discovering images through spatial queries. The heart of the KOA service is an R-tree-based, database-indexing mechanism prototyped by the Virtual Astronomical Observatory (VAO) and further developed by the Montage Image Mosaic project, designed to provide fast access to large imaging data sets as a first step in creating wide-area image mosaics (such as mosaics of subsets of the 4.7 million images of the SDSS DR9 release). The KOA service uses the results of the spatial R-tree search to create an SQLite data database for further relational filtering. The service uses a JSON configuration file to describe the association between instrument parameters and the service query parameters, and to make it applicable beyond the Keck instruments. The images generated at the Keck telescope usually do not encode the image footprints as WCS fields in the FITS file headers. Because SIAP searches are spatial, much of the effort in developing the program interface involved processing the instrument and telescope parameters to understand how accurately we can derive the WCS information for each instrument. This knowledge is now being fed back into the KOA databases as part of a program to include complete metadata information for all imaging observations. The R-tree program was itself extended to support temporal (in addition to spatial) indexing, in response to requests from the planetary science community for a search engine to discover observations of Solar System objects. With this 3D-indexing scheme, the service performs very fast time and spatial matches between the target ephemerides, obtained from the JPL SPICE service. Our experiments indicate these matches can be more than 100 times faster than when separating temporal and spatial searches. Images of the tracks of the moving targets, overlaid with the image footprints, are computed with a new command-line visualization tool, mViewer, released with the Montage distribution. The service is currently in test and will be released in late summer 2016.

  19. Thermodynamic correction of particle concentrations measured by underwing probes on fast flying aircraft

    NASA Astrophysics Data System (ADS)

    Weigel, R.; Spichtinger, P.; Mahnke, C.; Klingebiel, M.; Afchine, A.; Petzold, A.; Krämer, M.; Costa, A.; Molleker, S.; Jurkat, T.; Minikin, A.; Borrmann, S.

    2015-12-01

    Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable for different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions in certain distance away from the aircraft. Conventional procedures for scaling the measured number densities to ambient conditions presume that the particle penetration speed through the instruments' detection area equals the aircraft speed (True Air Speed, TAS). However, particle imaging instruments equipped with pitot-tubes measuring the Probe Air Speed (PAS) of each underwing probe reveal PAS values systematically below those of the TAS. We conclude that the deviation between PAS and TAS is mainly caused by the compression of the probed air sample. From measurements during two missions in 2014 with the German Gulfstream G-550 (HALO - High Altitude LOng range) research aircraft we develop a procedure to correct the measured particle concentration to ambient conditions using a thermodynamic approach. With the provided equation the corresponding concentration correction factor ξ is applicable to the high frequency measurements of each underwing probe which is equipped with its own air speed sensor (e.g. a pitot-tube). ξ-values of 1 to 0.85 are calculated for air speeds (i.e. TAS) between 60 and 260 m s-1. From HALO data it is found that ξ does not significantly vary between the different deployed instruments. Thus, for the current HALO underwing probe configuration a parameterisation of ξ as a function of TAS is provided for instances if PAS measurements are lacking. The ξ-correction yields higher ambient particle concentration by about 15-25 % compared to conventional procedures - an improvement which can be considered as significant for many research applications. The calculated ξ-values are specifically related to the considered HALO underwing probe arrangement and may differ for other aircraft or instrument geometries. Moreover, the ξ-correction may not cover all impacts originating from high flight velocities and from interferences between the instruments and, e.g., the aircraft wings and/or fuselage. Consequently, it is important that PAS (as a function of TAS) is individually measured by each probe deployed underneath the wings of a fast-flying aircraft.

  20. The relative responsiveness of test instruments can be estimated using a meta-analytic approach: an illustration with treatments for depression.

    PubMed

    Kounali, Daphne Z; Button, Katherine S; Lewis, Glyn; Ades, Anthony E

    2016-09-01

    We present a meta-analytic method that combines information on treatment effects from different instruments from a network of randomized trials to estimate instrument relative responsiveness. Five depression-test instruments [Beck Depression Inventory (BDI I/II), Patient Health Questionnaire (PHQ9), Hamilton Rating for Depression 17 and 24 items, Montgomery-Asberg Depression Rating] and three generic quality of life measures [EuroQoL (EQ-5D), SF36 mental component summary (SF36 MCS), and physical component summary (SF36 PCS)] were compared. Randomized trials of treatments for depression reporting outcomes on any two or more of these instruments were identified. Information on the within-trial ratios of standardized treatment effects was pooled across the studies to estimate relative responsiveness. The between-instrument ratios of standardized treatment effects vary across trials, with a coefficient of variation of 13% (95% credible interval: 6%, 25%). There were important differences between the depression measures, with PHQ9 being the most responsive instrument and BDI the least. Responsiveness of the EQ-5D and SF36 PCS was poor. SF36 MCS performed similarly to depression instruments. Information on relative responsiveness of several test instruments can be pooled across networks of trials reporting at least two outcomes, allowing comparison and ranking of test instruments that may never have been compared directly. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. A fast plasma analyser for the study of the solar wind interaction with Mars

    NASA Astrophysics Data System (ADS)

    James, Adrian Martin

    This thesis describes the design and development of the FONEMA instrument to be flown aboard the Russian mission to Mars in 1996. Many probes have flown to Mars yet despite this many mysteries still remain, among them the nature of the interaction of the solar wind with the planetary obstacle. In this thesis I will present some of the results from earlier spacecraft and the models of the interaction that they suggest paying particular attention to the contribution of ion analysers. From these results it will become clear that a fast ion sensor is needed to resolve many of the questions about the magnetosphere of Mars. The FONEMA instrument was designed for this job making use of a novel electrostatic mirror and particle collimator combined with parallel magnetic and electrostatic fields to resolve the ions into mass and energy bins. Development and production of the individual elements is discussed in detail.

  2. Solar Polar ORbit Telescope (SPORT): A Potential Heliophysics Mission of China

    NASA Astrophysics Data System (ADS)

    Liu, Ying

    We describe a spacecraft mission, named Solar Polar ORbit Telescope (SPORT), which is currently under a scientific and engineering background study in China. SPORT was originally proposed in 2004 by the National Space Science Center, Chinese Academy of Sciences. It will carry a suite of remote-sensing and in-situ instruments to observe coronal mass ejections (CMEs), solar high-latitude magnetism, and the fast solar wind from a polar orbit around the Sun. It is intended to be the first mission that carries remote-sensing instruments from a high-latitude orbit around the Sun and the first mission that could measure solar high-latitude magnetism. The first extended view of the polar region of the Sun and the ecliptic plane enabled by SPORT will provide a unique opportunity to study CME propagation through the inner heliosphere and solar high-latitude magnetism giving rise to eruptions and the fast solar wind.

  3. Insulin and GLP-1 infusions demonstrate the onset of adipose-specific insulin resistance in a large fasting mammal: potential glucogenic role for GLP-1.

    PubMed

    Viscarra, Jose A; Rodriguez, Ruben; Vazquez-Medina, Jose Pablo; Lee, Andrew; Tift, Michael S; Tavoni, Stephen K; Crocker, Daniel E; Ortiz, Rudy M

    2013-08-01

    Prolonged food deprivation increases lipid oxidation and utilization, which may contribute to the onset of the insulin resistance associated with fasting. Because insulin resistance promotes the preservation of glucose and oxidation of fat, it has been suggested to be an adaptive response to food deprivation. However, fasting mammals exhibit hypoinsulinemia, suggesting that the insulin resistance-like conditions they experience may actually result from reduced pancreatic sensitivity to glucose/capacity to secrete insulin. To determine whether fasting results in insulin resistance or in pancreatic dysfunction, we infused early- and late-fasted seals (naturally adapted to prolonged fasting) with insulin (0.065 U/kg), and a separate group of late-fasted seals with low (10 pM/kg) or high (100 pM/kg) dosages of glucagon-like peptide-1 (GLP-1) immediately following a glucose bolus (0.5g/kg), and measured the systemic and cellular responses. Because GLP-1 facilitates glucose-stimulated insulin secretion, these infusions provide a method to assess pancreatic insulin-secreting capacity. Insulin infusions increased the phosphorylation of insulin receptor and Akt in adipose and muscle of early and late fasted seals; however the timing of the signaling response was blunted in adipose of late fasted seals. Despite the dose-dependent increases in insulin and increased glucose clearance (high dose), both GLP-1 dosages produced increases in plasma cortisol and glucagon, which may have contributed to the glucogenic role of GLP-1. Results suggest that fasting induces adipose-specific insulin resistance in elephant seal pups, while maintaining skeletal muscle insulin sensitivity, and therefore suggests that the onset of insulin resistance in fasting mammals is an evolved response to cope with prolonged food deprivation.

  4. Temporal partitioning of adaptive responses of the murine heart to fasting.

    PubMed

    Brewer, Rachel A; Collins, Helen E; Berry, Ryan D; Brahma, Manoja K; Tirado, Brian A; Peliciari-Garcia, Rodrigo A; Stanley, Haley L; Wende, Adam R; Taegtmeyer, Heinrich; Rajasekaran, Namakkal Soorappan; Darley-Usmar, Victor; Zhang, Jianhua; Frank, Stuart J; Chatham, John C; Young, Martin E

    2018-03-15

    Recent studies suggest that the time of day at which food is consumed dramatically influences clinically-relevant cardiometabolic parameters (e.g., adiposity, insulin sensitivity, and cardiac function). Meal feeding benefits may be the result of daily periods of feeding and/or fasting, highlighting the need for improved understanding of the temporal adaptation of cardiometabolic tissues (e.g., heart) to fasting. Such studies may provide mechanistic insight regarding how time-of-day-dependent feeding/fasting cycles influence cardiac function. We hypothesized that fasting during the sleep period elicits beneficial adaptation of the heart at transcriptional, translational, and metabolic levels. To test this hypothesis, temporal adaptation was investigated in wild-type mice fasted for 24-h, or for either the 12-h light/sleep phase or the 12-h dark/awake phase. Fasting maximally induced fatty acid responsive genes (e.g., Pdk4) during the dark/active phase; transcriptional changes were mirrored at translational (e.g., PDK4) and metabolic flux (e.g., glucose/oleate oxidation) levels. Similarly, maximal repression of myocardial p-mTOR and protein synthesis rates occurred during the dark phase; both parameters remained elevated in the heart of fasted mice during the light phase. In contrast, markers of autophagy (e.g., LC3II) exhibited peak responses to fasting during the light phase. Collectively, these data show that responsiveness of the heart to fasting is temporally partitioned. Autophagy peaks during the light/sleep phase, while repression of glucose utilization and protein synthesis is maximized during the dark/active phase. We speculate that sleep phase fasting may benefit cardiac function through augmentation of protein/cellular constituent turnover. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Results of thermal test of metallic molybdenum disk target and fast-acting valve testing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Virgo, M.; Chemerisov, S.; Gromov, R.

    2016-12-01

    This report describes the irradiation conditions for thermal testing of helium-cooled metallic disk targets that was conducted on March 9, 2016, at the Argonne National Laboratory electron linac. The four disks in this irradiation were pressed and sintered by Oak Ridge National Laboratory from molybdenum metal powder. Two of those disks were instrumented with thermocouples. Also reported are results of testing a fast-acting-valve system, which was designed to protect the accelerator in case of a target-window failure.

  6. Fast logic?: Examining the time course assumption of dual process theory.

    PubMed

    Bago, Bence; De Neys, Wim

    2017-01-01

    Influential dual process models of human thinking posit that reasoners typically produce a fast, intuitive heuristic (i.e., Type-1) response which might subsequently be overridden and corrected by slower, deliberative processing (i.e., Type-2). In this study we directly tested this time course assumption. We used a two response paradigm in which participants have to give an immediate answer and afterwards are allowed extra time before giving a final response. In four experiments we used a range of procedures (e.g., challenging response deadline, concurrent load) to knock out Type 2 processing and make sure that the initial response was intuitive in nature. Our key finding is that we frequently observe correct, logical responses as the first, immediate response. Response confidence and latency analyses indicate that these initial correct responses are given fast, with high confidence, and in the face of conflicting heuristic responses. Findings suggest that fast and automatic Type 1 processing also cues a correct logical response from the start. We sketch a revised dual process model in which the relative strength of different types of intuitions determines reasoning performance. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. FASTSAT-HSV01 synergistic observations of the magnetospheric response during active periods: MINI-ME, PISA and TTI

    NASA Astrophysics Data System (ADS)

    Casas, Joseph; Collier, Michael; Rowland, Douglas; Sigwarth, John; Boudreaux, Mark

    Understanding the complex processes within the inner magnetosphere of Earth particularly during storm periods requires coordinated observations of the particle and field environment using both in-situ and remote sensing techniques. In fact in order to gain a better understand-ing of our Heliophysics and potentially improve our space weather forecasting capabilities, new observation mission approaches and new instrument technologies which can provide both cost effective and robust regular observations of magnetospheric activity and other space weather related phenomenon are necessary. As part of the effort to demonstrate new instrument tech-niques and achieve necessary coordinated observation missions, NASA's Fast Affordable Sci-ence and Technology Satellite Huntsville 01 mission (FASTSAT-HSV01) scheduled for launch in 2010 will afford a highly synergistic solution which satisfies payload mission opportunities and launch requirements as well as contributing in the near term to our improved understanding of Heliophysics. NASA's FASTSAT-HSV01 spacecraft on the DoD Space Test Program-S26 (STP-S26) Mission is a multi-payload mission executed by the DoD Space Test Program (STP) at the Space Development and Test Wing (SDTW), Kirtland AFB, NM. and is an example of a responsive and economical breakthrough in providing new possibilities for small space technology-driven and research missions. FASTSAT-HSV is a unique spacecraft platform that can carry multiple small instruments or experiments to low-Earth orbit on a wide range of expendable launch vehicles for a fraction of the cost traditionally required for such missions. The FASTSAT-HSV01 mission allows NASA to mature and transition a technical capability to industry while increasing low-cost access to space for small science and technology (ST) payloads. The FASTSAT-HSV01 payload includes three NASA Goddard Space Flight Center (GSFC) new technology built instruments that will study the terrestrial space environment and potentially contribute to space weather research in a synergistic manner. MINI-ME, a neutral atom imager, will observe the neutral atom inputs to ionospheric heating which can be important during high levels of magnetospheric activity. PISA, a plasma impedance spec-trometer, will measure simultaneously the local electron densities and temperatures as well as measure small scale density structure (500 m spatial scale) during these active periods. TTI, a thermospheric imager, will remotely determine the thermospheric temperature response to this magnetospheric activity. Together, these observations will contribute significantly to a comprehensive understanding of the flow of energy through and the response of the storm-time terrestrial magnetosphere.

  8. FASTSAT-HSV01 Synergistic Observations of the Magnetospheric Response During Active Periods: MINI-ME, PISA and TTI

    NASA Technical Reports Server (NTRS)

    Casas, Joseph C.; Collier, Michael R.; Rowland, Douglas E.; Sigwarth, John B.; Boudreaux, Mark E.

    2010-01-01

    Understanding the complex processes within the inner magnetosphere of Earth particularly during storm periods requires coordinated observations of the particle and field environment using both in-situ and remote sensing techniques. In fact in order to gain a better understanding of our Heliophysics and potentially improve our space weather forecasting capabilities, new observation mission approaches and new instrument technologies which can provide both cost effective and robust regular observations of magnetospheric activity and other space weather related phenomenon are necessary. As part of the effort to demonstrate new instrument techniques and achieve necessary coordinated observation missions, NASA's Fast Affordable Science and Technology Satellite Huntsville 01 mission (FASTSAT-HSVOI) scheduled for launch in 2010 will afford a highly synergistic solution which satisfies payload mission opportunities and launch requirements as well as contributing iri the near term to our improved understanding of Heliophysics. NASA's FASTSAT-HSV01 spacecraft on the DoD Space Test Program-S26 (STP-S26) Mission is a multi-payload mission executed by the DoD Space Test Program (STP) at the Space Development and Test Wing (SDTW), Kirtland AFB, NM. and is an example of a responsive and economical breakthrough in providing new possibilities for small space technology-driven and research missions. FASTSAT-HSV is a unique spacecraft platform that can carry multiple small instruments or experiments to low-Earth orbit on a wide range of expendable launch vehicles for a fraction of the cost traditionally required for such missions. The FASTSAT-HSV01 mission allows NASA to mature and transition a technical capability to industry while increasing low-cost access to space for small science and technology (ST) payloads. The FASTSAT-HSV01 payload includes three NASA Goddard Space Flight Center (GSFC) new technology built instruments that will study the terrestrial space environment and potentially contribute to space weather research in a synergistic manner. MINI-ME, a neutral atom imager, will observe the neutral atom inputs to ionospheric heating which can be important during high levels of magnetospheric activity. PISA, a plasma impedance spectrometer, will measure simultaneously the local electron densities and temperatures as well as measure small scale density structure (500 m spatial scale) during these active periods. TTI, a thermospheric imager, will remotely determine the thermospheric temperature response to this magnetospheric activity. Together, these observations will contribute significantly to a comprehensive understanding of the flow of energy through and the response of the storm-time terrestrial magnetosphere.

  9. Changes in responsiveness to serotonin on rat ventromedial hypothalamic neurons after food deprivation.

    PubMed

    Nishimura, F; Nishihara, M; Torii, K; Takahashi, M

    1996-07-01

    The effects of food deprivation on responsiveness of neurons in the ventromedial nucleus of the hypothalamus (VMH) to serotonin (5-HT), norepinephrine (NE), gamma-aminobutyric acid (GABA), and neuropeptide Y (NPY) were investigated using brain slices in vitro along with behavioral changes in vivo during fasting. Adult male rats were fasted for 48 h starting at the beginning of the dark phase (lights on: 0700-1900 h). The animals showed a significant loss of body weight on the second day of fasting and an increase in food consumption on the first day of refeeding. During fasting, voluntary locomotor activity was significantly increased in the light phase but not during the dark phase. Plasma catecholamine levels were not affected by fasting. In vitro electrophysiological study showed that, in normally fed rats, 5-HT and NE induced both excitatory and inhibitory responses, while GABA and NPY intensively suppressed unit activity in the VMH. Food deprivation for 48 h significantly changed the responsiveness of VMH neurons to 5-HT, for instance, the ratio of neurons whose activity was facilitated by 5-HT was significantly decreased. The responsiveness of VMH neurons to NE, GABA, and NPY was not affected by food deprivation. These results suggest that food deprivation decreases the facilitatory response of VMH neurons to 5-HT, and that this change in responsiveness to 5-HT is at least partially involved in the increase in food intake motivation and locomotor activity during fasting.

  10. 3-D Displays Perceptual Research and Applications to Military Systems

    DTIC Science & Technology

    1982-09-30

    physical button on the corresponding face of the response cube as fast as possible, while minimizing errors. Each observer served for six sessions...orientation, and this resulted in the fast flat reaction time function. The Rotat±nal Strategy: As can be seen from Figure 3, the 24 stimulus cube...instead of the TOP key, these two responses should show the fast , flat response time functions associated with use of the spatial strategy, whereas the

  11. Astrobo: Towards a new observatory control system for the Garching Observatory 0.6m

    NASA Astrophysics Data System (ADS)

    Schweyer, T.; Jarmatz, P.; Burwitz, V.

    2016-12-01

    The recently installed Campus Observatory Garching (COG) 0.6m telescope features a wide array of instruments, including a wide-field imager and a variety of spectrographs. To support all these different instruments and improve time usage, it was decided to develop a new control system from scratch, that will be able to safely observe autonomously as well as manually (for student lab courses). It is built using an hierarchical microservice architecture, which allows well-specified communication between its components regardless of the programming language used. This modular design allows for fast prototyping of components as well as easy implementation of complex instrumentation control software.

  12. Material Testing Device

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Small Business Innovation Research (SBIR) contracts led to two commercial instruments and a new subsidiary for Physical Sciences, Inc. (PSI). The FAST system, originally developed for testing the effect of space environment on materials, is now sold commercially for use in aging certification of materials intended for orbital operation. The Optical Temperature Monitor was designed for precise measurement of high temperatures on certain materials to be manufactured in space. The original research was extended to the development of a commercial instrument that measures and controls fuel gas temperatures in industrial boilers. PSI created PSI Environmental Instruments to market the system. The company also offers an Aerospace Measurement Service that has evolved from other SBIR contracts.

  13. Unsteady pressure measurement instrumentation using anodized-aluminium PSP applied in a transonic wind tunnel

    NASA Astrophysics Data System (ADS)

    Mérienne, Marie-Claire; LeSant, Yves; Ancelle, Jacques; Soulevant, Didier

    2004-12-01

    The objective of this work is to demonstrate the feasibility of pressure measurement instrumentation using anodized-aluminium pressure-sensitive paint (or AA-PSP) for application in unsteady flows. An anodized procedure was applied to an aluminium tape that can be easily placed on a model even when it is mounted in a wind tunnel. The response time of the PSP coating is assessed using a calibration rig that generates fast pressure steps or sinusoidal pressure fluctuations up to 1 kHz. A pointwise measurement system made with a Cassegrain telescope and a photomultiplier tube was designed to collect the PSP luminescence. The spot displacement on the model surface was carried out by using a 3D moving bench. A camera is used to identify the spot position according to the model geometry. An application in a wind tunnel was performed on a forced shock wave oscillation test, generating amplitude variations up to 25 kPa. The calibration problem due to non-uniformity of the anodized properties did not allow quantitative data processing of pressure levels. Nevertheless frequency analysis demonstrates that the coating is able to follow the pressure fluctuations, as shown by comparison with standard pressure transducers.

  14. A VCSEL based system for on-site monitoring of low level methane emission

    NASA Astrophysics Data System (ADS)

    Kannath, A.; Hodgkinson, J.; Gillard, R. G.; Riley, R. J.; Tatam, R. P.

    2011-03-01

    Continuous monitoring of methane emissions has assumed greater significance in the recent past due to increasing focus on global warming issues. Many industries have also identified the need for ppm level methane measurement as a means of gaining carbon credits. Conventional instruments based on NDIR spectroscopy are unable to offer the high selectivity and sensitivity required for such measurements. Here we discuss the development of a robust VCSEL based system for accurate low level measurements of methane. A possible area of application is the measurement of residual methane whilst monitoring the output of flare stacks and exhaust gases from methane combustion engines. The system employs a Wavelength Modulation Spectroscopy (WMS) scheme with second harmonic detection at 1651 nm. Optimum modulation frequency and ramp rates were chosen to maintain high resolution and fast response times which are vital for the intended application. Advanced data processing techniques were used to achieve long term sensitivity of the order of 10-5 in absorbance. The system is immune to cross interference from other gases and its inherent design features makes it ideal for large scale commercial production. The instrument maintains its calibration and offers a completely automated continuous monitoring solution for remote on site deployment.

  15. Investigation of three-dimensional flow field in a turbine including rotor/stator interaction. I - Design development and performance of the research facility

    NASA Technical Reports Server (NTRS)

    Lakshminarayana, B.; Camci, C.; Halliwell, I.; Zaccaria, M.

    1992-01-01

    A description of the Axial Flow Turbine Research Facility (AFTRF) installed at the Turbomachinery Laboratory of the Pennsylvania State University is presented in this paper. The facility diameter is 91.66 cm (3 feet) and the hub-to-tip ratio of the blading is 0.73. The flow path consists of turbulence generating grid, 23 nozzle vane and 29 rotor blades followed by outlet guide vanes. The blading design, carried out by General Electric Company personnel, embody modern HP turbine design philosophy, loading and flow coefficient, reaction, aspect ratio, and blade turning angles; all within the current aircraft engine design turbine practice. State-of-the-art quasi-3D blade design techniques were used to design the vane and the blade shapes. The vanes and blades are heavily instrumented with fast response pressure, shear stress, and velocity probes and have provision for flow visualization and laser Doppler anemometer measurement. Furthermore, provision has been made for detailed nozzle wake, rotor wake and boundary layer surveys. A 150 channel slip ring unit is used for transmitting the rotor data to a stationary instrumentation system. All the design objectives have been met.

  16. Rats socially-reared and full fed learned an autoshaping task, showing less levels of fear-like behaviour than fasted or singly-reared rats.

    PubMed

    Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia

    2004-07-01

    During the learning of instrumental tasks, rats are usually fasted to increase reinforced learning. However, fasting produces several undesirable side effects. The aim of this study was to test the hypothesis that control rats, i.e. full-fed and group-reared rats, will learn an autoshaping task to the same level as fasted or singly-reared rats. The interaction between fasting and single-rearing of rats was also tested. Results showed that control rats and fasted rats acquired the autoshaping task similarly, independently of rearing condition or gender. However, fasted or singly-reared rats produced fear-like behaviour, since male rats group-reared and fasted (85% body/wt, P <0.05), male rats singly-reared (full fed, P <0.05; 12 h fasted, P <0.05; 85% body/wt, P <0.05), female rats group-reared (12 h fasted, P <0.05; 85% body/wt, P <0.05) and female rats singly reared (full fed, P <0.05; 12 h fasted, P <0.05; 85% body/wt, P <0.05) displayed reduced amounts of time exploring the open arms of the elevated plus-maze. In conclusion, control rats learned the autoshaping task to the same level as fasted or singly-reared rats. However, fasting or single-rearing produced fear-like behaviour. Thus, the training of control rats in autoshaping tasks may be an option that improves animal welfare.

  17. Seismic instrumentation of buildings

    USGS Publications Warehouse

    Çelebi, Mehmet

    2000-01-01

    The purpose of this report is to provide information on how and why we deploy seismic instruments in and around building structures. The recorded response data from buildings and other instrumented structures can be and are being primarily used to facilitate necessary studies to improve building codes and therefore reduce losses of life and property during damaging earthquakes. Other uses of such data can be in emergency response situations in large urban environments. The report discusses typical instrumentation schemes, existing instrumentation programs, the steps generally followed in instrumenting a structure, selection and type of instruments, installation and maintenance requirements and data retrieval and processing issues. In addition, a summary section on how recorded response data have been utilized is included. The benefits from instrumentation of structural systems are discussed.

  18. Greater reward-related neuronal response to hedonic foods in women compared to men

    PubMed Central

    Legget, Kristina T.; Cornier, Marc-Andre; Bessesen, Daniel H.; Mohl, Brianne; Thomas, Elizabeth A.; Tregellas, Jason R.

    2017-01-01

    Objective The current study aimed to identify how sex influences neurobiological responses to food cues, particularly those related to hedonic eating, and how this relates to obesity propensity, using functional magnetic resonance imaging (fMRI). Methods Adult men and women who were either obesity-resistant (OR) or obesity-prone (OP) underwent fMRI while viewing visual food cues (hedonic foods, neutral foods, and non-food objects) in both fasted and fed states. Results When fasted, a significant sex effect on the response to hedonic vs. neutral foods was observed, with greater responses in women than men in the nucleus accumbens (p=0.0002) and insula (p=0.010). Sex-based differences were not observed in the fed state. No significant group effects (OP vs. OR) or group by sex interactions were observed in fasted or fed states. Conclusions Greater fasted responses to hedonic food cues in reward-related brain regions were observed in women compared to men, suggesting that women may be more sensitive to reward value of hedonic foods than men when fasted. This may indicate sex-dependent neurophysiology underlying eating behaviors. PMID:29239138

  19. New Fast Beam Conditions Monitoring (BCM1F) system for CMS

    NASA Astrophysics Data System (ADS)

    Zagozdzinska, A. A.; Bell, A. J.; Dabrowski, A. E.; Hempel, M.; Henschel, H. M.; Karacheban, O.; Przyborowski, D.; Leonard, J. L.; Penno, M.; Pozniak, K. T.; Miraglia, M.; Lange, W.; Lohmann, W.; Ryjov, V.; Lokhovitskiy, A.; Stickland, D.; Walsh, R.

    2016-01-01

    The CMS Beam Radiation Instrumentation and Luminosity (BRIL) project is composed of several systems providing the experiment protection from adverse beam conditions while also measuring the online luminosity and beam background. Although the readout bandwidth of the Fast Beam Conditions Monitoring system (BCM1F—one of the faster monitoring systems of the CMS BRIL), was sufficient for the initial LHC conditions, the foreseen enhancement of the beams parameters after the LHC Long Shutdown-1 (LS1) imposed the upgrade of the system. This paper presents the new BCM1F, which is designed to provide real-time fast diagnosis of beam conditions and instantaneous luminosity with readout able to resolve the 25 ns bunch structure.

  20. Simultaneous Retrieval of Temperature, Water Vapor and Ozone Atmospheric Profiles from IASI: Compression, De-noising, First Guess Retrieval and Inversion Algorithms

    NASA Technical Reports Server (NTRS)

    Aires, F.; Rossow, W. B.; Scott, N. A.; Chedin, A.; Hansen, James E. (Technical Monitor)

    2001-01-01

    A fast temperature water vapor and ozone atmospheric profile retrieval algorithm is developed for the high spectral resolution Infrared Atmospheric Sounding Interferometer (IASI) space-borne instrument. Compression and de-noising of IASI observations are performed using Principal Component Analysis. This preprocessing methodology also allows, for a fast pattern recognition in a climatological data set to obtain a first guess. Then, a neural network using first guess information is developed to retrieve simultaneously temperature, water vapor and ozone atmospheric profiles. The performance of the resulting fast and accurate inverse model is evaluated with a large diversified data set of radiosondes atmospheres including rare events.

  1. SPORT: A new sub-nanosecond time-resolved instrument to study swift heavy ion-beam induced luminescence - Application to luminescence degradation of a fast plastic scintillator

    NASA Astrophysics Data System (ADS)

    Gardés, E.; Balanzat, E.; Ban-d'Etat, B.; Cassimi, A.; Durantel, F.; Grygiel, C.; Madi, T.; Monnet, I.; Ramillon, J.-M.; Ropars, F.; Lebius, H.

    2013-02-01

    We developed a new sub-nanosecond time-resolved instrument to study the dynamics of UV-visible luminescence under high stopping power heavy ion irradiation. We applied our instrument, called SPORT, on a fast plastic scintillator (BC-400) irradiated with 27-MeV Ar ions having high mean electronic stopping power of 2.6 MeV/μm. As a consequence of increasing permanent radiation damages with increasing ion fluence, our investigations reveal a degradation of scintillation intensity together with, thanks to the time-resolved measurement, a decrease in the decay constant of the scintillator. This combination indicates that luminescence degradation processes by both dynamic and static quenching, the latter mechanism being predominant. Under such high density excitation, the scintillation deterioration of BC-400 is significantly enhanced compared to that observed in previous investigations, mainly performed using light ions. The observed non-linear behaviour implies that the dose at which luminescence starts deteriorating is not independent on particles' stopping power, thus illustrating that the radiation hardness of plastic scintillators can be strongly weakened under high excitation density in heavy ion environments.

  2. The 2 Pi Charged Particles Analyzer: All-Sky Camera Concept and Development for Space Missions

    NASA Technical Reports Server (NTRS)

    Vaisberg, O.; Berthellier, J.-J.; Moore, T.; Avanov, L.; Leblanc, F.; Leblanc, F.; Moiseev, P.; Moiseenko, D.; Becker, J.; Collier, M.; hide

    2016-01-01

    Increasing the temporal resolution and instant coverage of velocity space of space plasma measurements is one of the key issues for experimentalists. Today, the top-hat plasma analyzer appears to be the favorite solution due to its relative simplicity and the possibility to extend its application by adding a mass-analysis section and an electrostatic angular scanner. Similarly, great success has been achieved in MMS mission using such multiple top-hat analyzers to achieve unprecedented temporal resolution. An instantaneous angular coverage of charged particles measurements is an alternative approach to pursuing the goal of high time resolution. This was done with 4-D Fast Omnidirectional Nonscanning Energy Mass Analyzer and, to a lesser extent, by DYMIO instruments for Mars-96 and with the Fast Imaging Plasma Spectrometer instrument for MErcury Surface, Space ENvironment, GEochemistry, and Ranging mission. In this paper we describe, along with precursors, a plasma analyzer with a 2 electrostatic mirror that was developed originally for the Phobos-Soil mission with a follow-up in the frame of the BepiColombo mission and is under development for future Russian missions. Different versions of instrument are discussed along with their advantages and drawbacks.

  3. Performance of a Space-Based Wavelet Compressor for Plasma Count Data on the MMS Fast Plasma Investigation

    NASA Technical Reports Server (NTRS)

    Barrie, A. C.; Smith, S. E.; Dorelli, J. C.; Gershman, D. J.; Yeh, P.; Schiff, C.; Avanov, L. A.

    2017-01-01

    Data compression has been a staple of imaging instruments for years. Recently, plasma measurements have utilized compression with relatively low compression ratios. The Fast Plasma Investigation (FPI) on board the Magnetospheric Multiscale (MMS) mission generates data roughly 100 times faster than previous plasma instruments, requiring a higher compression ratio to fit within the telemetry allocation. This study investigates the performance of a space-based compression standard employing a Discrete Wavelet Transform and a Bit Plane Encoder (DWT/BPE) in compressing FPI plasma count data. Data from the first 6 months of FPI operation are analyzed to explore the error modes evident in the data and how to adapt to them. While approximately half of the Dual Electron Spectrometer (DES) maps had some level of loss, it was found that there is little effect on the plasma moments and that errors present in individual sky maps are typically minor. The majority of Dual Ion Spectrometer burst sky maps compressed in a lossless fashion, with no error introduced during compression. Because of induced compression error, the size limit for DES burst images has been increased for Phase 1B. Additionally, it was found that the floating point compression mode yielded better results when images have significant compression error, leading to floating point mode being used for the fast survey mode of operation for Phase 1B. Despite the suggested tweaks, it was found that wavelet-based compression, and a DWT/BPE algorithm in particular, is highly suitable to data compression for plasma measurement instruments and can be recommended for future missions.

  4. Review of Transient Testing of Fast Reactor Fuels in the Transient REActor Test Facility (TREAT)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jensen, C.; Wachs, D.; Carmack, J.

    The restart of the Transient REActor Test (TREAT) facility provides a unique opportunity to engage the fast reactor fuels community to reinitiate in-pile experimental safety studies. Historically, the TREAT facility played a critical role in characterizing the behavior of both metal and oxide fast reactor fuels under off-normal conditions, irradiating hundreds of fuel pins to support fast reactor fuel development programs. The resulting test data has provided validation for a multitude of fuel performance and severe accident analysis computer codes. This paper will provide a review of the historical database of TREAT experiments including experiment design, instrumentation, test objectives, andmore » salient findings. Additionally, the paper will provide an introduction to the current and future experiment plans of the U.S. transient testing program at TREAT.« less

  5. Fed, but not Fasted, Adrenalectomized Rats Survive the Stress of Hemorrhage and Hypovolemia

    NASA Technical Reports Server (NTRS)

    Darlington, Daniel N.; Neves, Robert B.; Ha, Taryn; Chew, Gordon; Dallman, Mary F.

    1990-01-01

    We have recently shown that conscious adrenalectomized rats exhibit nearly normal recovery of arterial blood pressure during the 5 h after hemorrhage. In those experiments, it appeared that a previous reduction in food intake might have compromised the recovery of blood pressure and increased mortality. These experiments were designed to test in conscious sham-adrenalectomized (control) and adrenalectomized rats prepared with indwelling arterial and venous cannulae: 1. The effects of a 20- to 24-h fast (compared to rats fed ab libitum) on the mobilization of plasma substrates and recovery of arterial blood pressure after a 15 ml/kg - 5 min hemorrhage, and 2. Vascular responsivity to pressor agents in fed or fasted groups before or 2 h after hemorrhage. In all rats hemorrhage resulted in decreased arterial pressure and heart rate. Arterial pressure recovered to near normal in both fed and fasted control groups and in the led adrenalectomized rats, and all of these rats survived for 24 h after stress. By contrast, in the fasted adrenalectomized rats, arterial pressure recovered only during the first 1.5 - 2 h and then failed, resulting in 100% mortality by 3-5 h. Compared to the other three groups, in which substrate levels either increased or remained fairly stable, plasma glucose and beta-hydoxybutyrate concentrations fell steadily, from 1.5-2 h after hemorrhage until death occurred in the fasted adrenalectomized rats. Basal ACTH concentrations were elevated cormpared to control values in both adrenalectomized groups (fed and fasted). Hemorrhage caused increases in plasma ACTH in all groups; the magnitude of the responses did not differ among the groups. The dilution of Evans' blue dve after hemorrhage (used as an index of fluid movement into the vascular space) was not different in contol and adrenalectomized rats (either fed or fasted). There were no differences in pressor responses to phenylephrine, vasopressin, or angiotensin-II between the fed and fasted condition in the control rats either before or after hemorrhage. There was a fasting-associated decrease in vascular responsivity, to vasopressin, but normal responsivity to phenylephrine and angiotensin-II, in the adrenal-ectomized rats both before and after hemorrhage. We conclude that: (1) since fed adrenalectomized rats all survived the stress, adrenal hormones are not required for survival unless fasting is a prior condition; (2) vascular responsiveness to phenylephrine and angiotensin-II is not altered by fasting and is, therefore, probably not the proximate cause of cardiovascular svstem failure; and (3) from these data we cannot distinguish between a failure in substrate supply and a failure in some component of the cardiovascular svstem, other than vascular responsivity, that results in death after hemorrhage in fasted adrenalectomized rats.

  6. Governing childhood obesity: framing regulation of fast food advertising in the Australian print media.

    PubMed

    Henderson, Julie; Coveney, John; Ward, Paul; Taylor, Anne

    2009-11-01

    Childhood obesity is widely constructed as reaching epidemic proportions with consumption of fast food viewed as a contributing factor. This paper analyses media reporting of the regulation of fast food consumption to children. A media search of five Australian newspapers for the period January 2006 to June 2008 elicited 100 articles relating to the regulation of fast food advertising to children. Content and thematic analysis of the articles reveal conflicting perspectives on the role of the state; the level of accountability of the food and advertising industries; and responsibilities of parents for regulating fast food consumption in children. The Federal Government, food and advertising industries and free to air broadcasters favour industry self-regulation and personal responsibility for fast food consumption while the proponents of government regulation include consumer groups, state government health ministers, nutrition and public health academics and medical and health foundations. The regulation of fast food advertising to children is discussed in relation to ideas about governance and the public health strategies which follow from these ideas. The paper argues that all proposed solutions are indicative of a neoliberal approach to the governance of health insofar as the responsibility for regulation of food marketing is viewed as lying with industry and the regulation of lifestyle risk is viewed as an individual responsibility.

  7. Measuring the dependence of the decay curve on the electron energy deposit in NaI(Tl)

    NASA Astrophysics Data System (ADS)

    Choong, W.-S.; Bizarri, G.; Cherepy, N. J.; Hull, G.; Moses, W. W.; Payne, S. A.

    2011-08-01

    We report on the first measurement of the decay times of NaI(Tl) as a function of the deposited electron energy. It has been suggested that the decay curve depends on the ionization density, which is correlated with the electron energy deposit in the scintillator. The ionization creates excitation states, which can decay radiatively and non-radiatively through a number of competing processes. As a result, the rate at which the excitation decays depends on the ionization density. A measurement of the decay curve as a function of the ionization density will allow us to probe the kinetic rates of the competing processes. The Scintillator Light Yield Non-proportionality Characterization Instrument (SLYNCI) measures the electron response of scintillators utilizing fast sampling ADCs to digitize the raw signals from the detectors, and so can provide a measurement of the light pulse shape from the scintillator. Using data collected with the SLYNCI instrument, the intrinsic scintillation profile is extracted on an event-by-event basis by deconvolving the raw signal with the impulse response of the system. Scintillation profiles with the same electron energy deposit are summed to obtain decay curves as a function of the deposited electron energy. The decay time constants are obtained by fitting the decay curves with a two-component exponential decay. While a slight dependence of the decay time constants on the electron energy deposit is observed, the results are not statistically significant.

  8. An inverse-modelling approach for frequency response correction of capacitive humidity sensors in ABL research with small remotely piloted aircraft (RPA)

    NASA Astrophysics Data System (ADS)

    Wildmann, N.; Kaufmann, F.; Bange, J.

    2014-09-01

    The measurement of water vapour concentration in the atmosphere is an ongoing challenge in environmental research. Satisfactory solutions exist for ground-based meteorological stations and measurements of mean values. However, carrying out advanced research of thermodynamic processes aloft as well, above the surface layer and especially in the atmospheric boundary layer (ABL), requires the resolution of small-scale turbulence. Sophisticated optical instruments are used in airborne meteorology with manned aircraft to achieve the necessary fast-response measurements of the order of 10 Hz (e.g. LiCor 7500). Since these instruments are too large and heavy for the application on small remotely piloted aircraft (RPA), a method is presented in this study that enhances small capacitive humidity sensors to be able to resolve turbulent eddies of the order of 10 m. The sensor examined here is a polymer-based sensor of the type P14-Rapid, by the Swiss company Innovative Sensor Technologies (IST) AG, with a surface area of less than 10 mm2 and a negligible weight. A physical and dynamical model of this sensor is described and then inverted in order to restore original water vapour fluctuations from sensor measurements. Examples of flight measurements show how the method can be used to correct vertical profiles and resolve turbulence spectra up to about 3 Hz. At an airspeed of 25 m s-1 this corresponds to a spatial resolution of less than 10 m.

  9. Measuring Power Flow in Electric Vehicles

    NASA Technical Reports Server (NTRS)

    Griffin, Daniel C., Jr; Wiker, G. A.

    1983-01-01

    Instrument accommodates fast rise and fall times of waveforms characteristic of modern, efficient power controllers. Power meter multiplies analog signals proportional to voltage and current, and converts resulting signal to frequency. Two mechanical counters provided: one for charging, one for discharging.

  10. Genetic risk score of common genetic variants for impaired fasting glucose and newly diagnosed type 2 diabetes influences oxidative stress.

    PubMed

    Kim, Minjoo; Kim, Minkyung; Huang, Limin; Jee, Sun Ha; Lee, Jong Ho

    2018-05-18

    We tested the hypothesis that the cumulative effects of common genetic variants related to elevated fasting glucose are collectively associated with oxidative stress. Using 25 single nucleotide polymorphisms (SNPs), a weighted genetic risk score (wGRS) was constructed by summing nine risk alleles based on nominal significance and a consistent effect direction in 1,395 controls and 718 patients with impaired fasting glucose (IFG) or newly diagnosed type 2 diabetes. All the participants were divided into the following three groups: low-wGRS, middle-wGRS, and high-wGRS groups. Among the nine SNPs, five SNPs were significantly associated with IFG and type 2 diabetes in this Korean population. wGRS was significantly associated with increased IFG and newly diagnosed type 2 diabetes (p = 6.83 × 10 -14 , odds ratio = 1.839) after adjusting for confounding factors. Among the IFG and type 2 diabetes patients, the fasting serum glucose and HbA 1c levels were significantly higher in the high-wGRS group than in the other groups. The urinary 8-epi-PGF 2α and malondialdehyde concentrations were significantly higher in the high-wGRS group than in the other groups. Moreover, general population-level instrumental variable estimation (using wGRS as an instrument) strengthened the causal effect regarding the largely adverse influence of high levels of fasting serum glucose on markers of oxidative stress in the Korean population. Thus, the combination of common genetic variants with small effects on IFG and newly diagnosed type 2 diabetes are significantly associated with oxidative stress.

  11. Changes in metabolism in response to fasting and food restriction in the Steller sea lion (Eumetopias jubatus).

    PubMed

    Rosen, David A S; Trites, Andrew W

    2002-06-01

    Many animals lower their resting metabolism (metabolic depression) when fasting or consuming inadequate food. We sought to document this response by subjecting five Steller sea lions to periods of: (1) complete fasting; or (2) restricting them to 50% of their normal herring diet. The sea lions lost an average of 1.5% of their initial body mass per day (2.30 kg/d) during the 9-14-day fast, and their resting metabolic rates decreased 31%, which is typical of a "fasting response". However, metabolic depression did not occur during the 28-day food restriction trials, despite the loss of 0.30% of body mass per day (0.42 kg/d). This difference in response suggests that undernutrition caused by reduced food intake may stimulate a "hunger response", which in turn might lead to increased foraging effort. The progressive changes in metabolism we observed during the fasts were related to, but were not directly caused by, changes in body mass from control levels. Combining these results with data collected from experiments when Steller sea lions were losing mass on low energy squid and pollock diets reveals a strong relationship between relative changes in body mass and relative changes in resting metabolism across experimental conditions. While metabolic depression caused by fasting or consuming large amounts of low energy food reduced the direct costs from resting metabolism, it was insufficient to completely overcome the incurred energy deficit.

  12. The instrument for investigating magnetic fields of isochronous cyclotrons

    NASA Astrophysics Data System (ADS)

    Avreline, N. V.

    2017-12-01

    A new instrument was designed and implemented in order to increase the measurement accuracy of magnetic field maps for isochronous Cyclotrons manufactured by Advanced Cyclotron Systems Inc. This instrument uses the Hall Probe (HP) from New Zealand manufacturer Group3. The specific probe used is MPT-141 HP and can measure magnetic field in the range from 2G to 21kG. Use of a fast ADC NI9239 module and error reduction algorithms, based on a polynomial regression method, allowed to reduce the noise to 0.2G. The design of this instrument allows to measure high gradient magnetic fields, as the resolution of the HP arm angle is within 0.0005° and the radial position resolution is within 25μm. A set of National Instrument interfaces connected to a desktop computer through a network are used as base control and data acquisition systems.

  13. Fast and Adaptive Lossless On-Board Hyperspectral Data Compression System for Space Applications

    NASA Technical Reports Server (NTRS)

    Aranki, Nazeeh; Bakhshi, Alireza; Keymeulen, Didier; Klimesh, Matthew

    2009-01-01

    Efficient on-board lossless hyperspectral data compression reduces the data volume necessary to meet NASA and DoD limited downlink capabilities. The techniques also improves signature extraction, object recognition and feature classification capabilities by providing exact reconstructed data on constrained downlink resources. At JPL a novel, adaptive and predictive technique for lossless compression of hyperspectral data was recently developed. This technique uses an adaptive filtering method and achieves a combination of low complexity and compression effectiveness that far exceeds state-of-the-art techniques currently in use. The JPL-developed 'Fast Lossless' algorithm requires no training data or other specific information about the nature of the spectral bands for a fixed instrument dynamic range. It is of low computational complexity and thus well-suited for implementation in hardware, which makes it practical for flight implementations of pushbroom instruments. A prototype of the compressor (and decompressor) of the algorithm is available in software, but this implementation may not meet speed and real-time requirements of some space applications. Hardware acceleration provides performance improvements of 10x-100x vs. the software implementation (about 1M samples/sec on a Pentium IV machine). This paper describes a hardware implementation of the JPL-developed 'Fast Lossless' compression algorithm on a Field Programmable Gate Array (FPGA). The FPGA implementation targets the current state of the art FPGAs (Xilinx Virtex IV and V families) and compresses one sample every clock cycle to provide a fast and practical real-time solution for Space applications.

  14. Rapid onset of hypoxic vasoconstriction in isolated lungs.

    PubMed

    Jensen, K S; Micco, A J; Czartolomna, J; Latham, L; Voelkel, N F

    1992-05-01

    A fast-response O2 analyzer that samples air at low flow rates allows the quasi-instantaneous measurement of O2 concentration change in the airways of isolated blood-perfused rat lungs. This instrument and an oximeter were used to measure the stimulus-response delay time of hypoxic pulmonary vasoconstriction when the lungs were challenged with 10, 5, or 3% O2. The estimate for the shortest delay time between accomplished fall in airway O2 concentration and the onset of hypoxia-induced vasoconstriction was approximately 7 s. We found that the slope of pressure rise, but not the stimulus-response delay time, correlated with the magnitude of hypoxic vasoconstriction. Oscillations in pulmonary arterial pressure were observed when the lungs were challenged with 10% O2 but not when the challenge was 12, 5, or 3%, indicating perhaps that these oscillations were a threshold phenomenon. Established hypoxic vasoconstriction was sensitive to brief changes in airway O2 concentration. Vasodilation occurred when the gas mixture was switched from 3 to 21% O2 for two to five breaths, and vasoconstriction occurred when the gas was changed during a single breath from 5 to 3% O2.

  15. An ultrahigh-accuracy Miniature Dew Point Sensor based on an Integrated Photonics Platform.

    PubMed

    Tao, Jifang; Luo, Yu; Wang, Li; Cai, Hong; Sun, Tao; Song, Junfeng; Liu, Hui; Gu, Yuandong

    2016-07-15

    The dew point is the temperature at which vapour begins to condense out of the gaseous phase. The deterministic relationship between the dew point and humidity is the basis for the industry-standard "chilled-mirror" dew point hygrometers used for highly accurate humidity measurements, which are essential for a broad range of industrial and metrological applications. However, these instruments have several limitations, such as high cost, large size and slow response. In this report, we demonstrate a compact, integrated photonic dew point sensor (DPS) that features high accuracy, a small footprint, and fast response. The fundamental component of this DPS is a partially exposed photonic micro-ring resonator, which serves two functions simultaneously: 1) sensing the condensed water droplets via evanescent fields and 2) functioning as a highly accurate, in situ temperature sensor based on the thermo-optic effect (TOE). This device virtually eliminates most of the temperature-related errors that affect conventional "chilled-mirror" hygrometers. Moreover, this DPS outperforms conventional "chilled-mirror" hygrometers with respect to size, cost and response time, paving the way for on-chip dew point detection and extension to applications for which the conventional technology is unsuitable because of size, cost, and other constraints.

  16. An ultrahigh-accuracy Miniature Dew Point Sensor based on an Integrated Photonics Platform

    NASA Astrophysics Data System (ADS)

    Tao, Jifang; Luo, Yu; Wang, Li; Cai, Hong; Sun, Tao; Song, Junfeng; Liu, Hui; Gu, Yuandong

    2016-07-01

    The dew point is the temperature at which vapour begins to condense out of the gaseous phase. The deterministic relationship between the dew point and humidity is the basis for the industry-standard “chilled-mirror” dew point hygrometers used for highly accurate humidity measurements, which are essential for a broad range of industrial and metrological applications. However, these instruments have several limitations, such as high cost, large size and slow response. In this report, we demonstrate a compact, integrated photonic dew point sensor (DPS) that features high accuracy, a small footprint, and fast response. The fundamental component of this DPS is a partially exposed photonic micro-ring resonator, which serves two functions simultaneously: 1) sensing the condensed water droplets via evanescent fields and 2) functioning as a highly accurate, in situ temperature sensor based on the thermo-optic effect (TOE). This device virtually eliminates most of the temperature-related errors that affect conventional “chilled-mirror” hygrometers. Moreover, this DPS outperforms conventional “chilled-mirror” hygrometers with respect to size, cost and response time, paving the way for on-chip dew point detection and extension to applications for which the conventional technology is unsuitable because of size, cost, and other constraints.

  17. Evaluation of new technique of sterilization using biological indicator.

    PubMed

    Sheth, Nomal Chintan; Rathod, Yogesh V; Shenoi, Pratima R; Shori, Deepa D; Khode, Rajiv T; Khadse, Amruta P

    2017-01-01

    A novel technique of sterilization of endodontic files is introduced in this article. Newly introduced sterilization unit, named "SteriFast" is compared with autoclave and glass bead sterilizer using biological indicator. Spore strips of Bacillus pumilus were cultured in nutrient broth. This cultured media was used to contaminate the experimental samples of endodontic files. These contaminated files were sterilized using three different techniques. The sterilized files were transferred into nutrient medium under aseptic condition. The results were observed after 24 h, 48 h, and 7 days. The results showed that autoclave and new sterilization device (SteriFast) showed complete sterilization. The files sterilized using glass bead sterilizer showed bacterial growth (80%). Thus, it proves that autoclave and SteriFast are ideal techniques of sterilization of endodontic files. Glass bead sterilizer does not completely sterilize the files. The article also compares SteriFast and autoclave in other aspects such as its design, basic principle, advantages, and disadvantages. The article also describes features and design of SteriFast, used for all kind of small dental instruments.

  18. Development of Mobile Measurement Method Series OTM 33

    EPA Science Inventory

    Starting in 2006, the United States Environmental Protection Agency has explored use of mobile instrumented vehicles for a variety of air quality assessment applications under its Geospatial Measurement of Air Pollution (GMAP) program. GMAP systems utilize next generation, fast-r...

  19. Study of Static Microchannel Plate Saturation Effects for the Fast Plasma Investigation Dual Electron Spectrometers on NASA's Magnetospheric MultiScale Mission

    NASA Technical Reports Server (NTRS)

    Avanov, L. A.; Gliese, U.; Pollock, C. J.; Moore, T. E.; Chornay, D. J.; Barrie, A. C.; Kujawski, J. T.; Gershman, D. J.; Tucker, C. J.; Mariano, A.; hide

    2015-01-01

    Imaging detecting systems based on microchannel plates (MCPs) are the most common for low energy plasma measurements for both space borne and ground applications. One of the key parameters of these detection systems is the dynamic range of the MCP's response to the input fluxes of charged particles. For most applications the dynamic range of the linear response should be as wide as possible. This is especially true for the Dual Electron Spectrometers (DESs) of the Fast Plasma Investigation (FPI) on NASA's Magnetospheric MultiScale (MMS) mission because a wide range of input fluxes are expected. To make use of the full available dynamic range, it is important to understand the MCP response behavior beyond the linear regime where the MCPs start to saturate. We have performed extensive studies of this during the characterization and calibration of the DES instruments and have identified several saturation effects of the detection system. The MCP itself exhibits saturation when the channels lack the ability to replenish charge sufficiently rapidly. It is found and will be shown that the ground system can significantly impact the correct measurement of this effect. As the MCP starts to saturate, the resulting pulse height distribution (PHD) changes shape and location (with less pulse height values), which leads to truncation of the PHD by the threshold set on the detection system discriminator. Finally, the detection system pulse amplifier exhibits saturation as the input flux drives pulse rates greater than its linear response speed. All of these effects effectively change the dead time of the overall detection system and as a result can affect the quality and interpretation of the flight data. We present results of detection system saturation effects and their interaction with special emphasis on the MCP related effects.

  20. Two instruments based on differential optical absorption spectroscopy (DOAS) to measure accurate ammonia concentrations in the atmosphere

    NASA Astrophysics Data System (ADS)

    Volten, H.; Bergwerff, J. B.; Haaima, M.; Lolkema, D. E.; Berkhout, A. J. C.; van der Hoff, G. R.; Potma, C. J. M.; Wichink Kruit, R. J.; van Pul, W. A. J.; Swart, D. P. J.

    2011-08-01

    We present two Differential Optical Absorption Spectroscopy (DOAS) instruments built at RIVM, the RIVM DOAS and the miniDOAS. Both instruments provide virtually interference free measurements of NH3 concentrations in the atmosphere, since they measure over an open path, without suffering from inlet problems or interference problems by ammonium aerosols dissociating on tubes or filters. They measure concentrations up to at least 200 μg m-3, have a fast response, low maintenance demands, and a high up-time. The RIVM DOAS has a high accuracy of typically 0.15 μg m-3 for ammonia over 5-min averages and over a total light path of 100 m. The miniDOAS has been developed for application in measurement networks such as the Dutch National Air Quality Monitoring Network (LML). Compared to the RIVM DOAS it has a similar accuracy, but is significantly reduced in size, costs, and handling complexity. The RIVM DOAS and miniDOAS results showed excellent agreement (R2 = 0.996) during a field measurement campaign in Vredepeel, the Netherlands. This measurement site is located in an agricultural area and is characterized by highly variable, but on average high ammonia concentrations in the air. The RIVM-DOAS and miniDOAS results were compared to the results of the AMOR instrument, a continuous-flow wet denuder system, which is currently used in the LML. Averaged over longer time spans of typically a day the (mini)DOAS and AMOR results agree reasonably well, although an offset of the AMOR values compared to the (mini)DOAS results exists. On short time scales the (mini)DOAS shows a faster response and does not show the memory effects due to inlet tubing and transport of absorption fluids encountered by the AMOR. Due to its high accuracy, high uptime, low maintenance and its open path, the (mini)DOAS shows a good potential for flux measurements by using two (or more) systems in a gradient set-up and applying the aerodynamic gradient technique.

  1. Two instruments based on differential optical absorption spectroscopy (DOAS) to measure accurate ammonia concentrations in the atmosphere

    NASA Astrophysics Data System (ADS)

    Volten, H.; Bergwerff, J. B.; Haaima, M.; Lolkema, D. E.; Berkhout, A. J. C.; van der Hoff, G. R.; Potma, C. J. M.; Wichink Kruit, R. J.; van Pul, W. A. J.; Swart, D. P. J.

    2012-02-01

    We present two Differential Optical Absorption Spectroscopy (DOAS) instruments built at RIVM: the RIVM DOAS and the miniDOAS. Both instruments provide virtually interference-free measurements of NH3 concentrations in the atmosphere, since they measure over an open path, without suffering from inlet problems or interference problems by ammonium aerosols dissociating on tubes or filters. They measure concentrations up to at least 200 μg m-3, have a fast response, low maintenance demands, and a high up-time. The RIVM DOAS has a high accuracy of typically 0.15 μg m-3 for ammonia for 5-min averages and over a total light path of 100 m. The miniDOAS has been developed for application in measurement networks such as the Dutch National Air Quality Monitoring Network (LML). Compared to the RIVM DOAS it has a similar accuracy, but is significantly reduced in size, costs, and handling complexity. The RIVM DOAS and miniDOAS results showed excellent agreement (R2 = 0.996) during a field measurement campaign in Vredepeel, the Netherlands. This measurement site is located in an agricultural area and is characterized by highly variable, but on average high ammonia concentrations in the air. The RIVM-DOAS and miniDOAS results were compared to the results of the AMOR instrument, a continuous-flow wet denuder system, which is currently used in the LML. Averaged over longer time spans of typically a day, the (mini)DOAS and AMOR results agree reasonably well, although an offset of the AMOR values compared to the (mini)DOAS results exists. On short time scales, the (mini)DOAS shows a faster response and does not show the memory effects due to inlet tubing and transport of absorption fluids encountered by the AMOR. Due to its high accuracy, high uptime, low maintenance and its open path, the (mini)DOAS shows a good potential for flux measurements by using two (or more) systems in a gradient set-up and applying the aerodynamic gradient technique.

  2. A novel approach to neutron dosimetry.

    PubMed

    Balmer, Matthew J I; Gamage, Kelum A A; Taylor, Graeme C

    2016-11-01

    Having been overlooked for many years, research is now starting to take into account the directional distribution of neutron workplace fields. Existing neutron dosimetry instrumentation does not account for this directional distribution, resulting in conservative estimates of dose in neutron workplace fields (by around a factor of 2, although this is heavily dependent on the type of field). This conservatism could influence epidemiological studies on the health effects of radiation exposure. This paper reports on the development of an instrument which can estimate the effective dose of a neutron field, accounting for both the direction and the energy distribution. A 6 Li-loaded scintillator was used to perform neutron assays at a number of locations in a 20 × 20 × 17.5 cm 3 water phantom. The variation in thermal and fast neutron response to different energies and field directions was exploited. The modeled response of the instrument to various neutron fields was used to train an artificial neural network (ANN) to learn the effective dose and ambient dose equivalent of these fields. All experimental data published in this work were measured at the National Physical Laboratory (UK). Experimental results were obtained for a number of radionuclide source based neutron fields to test the performance of the system. The results of experimental neutron assays at 25 locations in a water phantom were fed into the trained ANN. A correlation between neutron counting rates in the phantom and neutron fluence rates was experimentally found to provide dose rate estimates. A radionuclide source behind shadow cone was used to create a more complex field in terms of energy and direction. For all fields, the resulting estimates of effective dose rate were within 45% or better of their calculated values, regardless of energy distribution or direction for measurement times greater than 25 min. This work presents a novel, real-time, approach to workplace neutron dosimetry. It is believed that in the research presented in this paper, for the first time, a single instrument has been able to estimate effective dose.

  3. Nurse-surgeon object transfer: video analysis of communication and situation awareness in the operating theatre.

    PubMed

    Korkiakangas, Terhi; Weldon, Sharon-Marie; Bezemer, Jeff; Kneebone, Roger

    2014-09-01

    One of the most central collaborative tasks during surgical operations is the passing of objects, including instruments. Little is known about how nurses and surgeons achieve this. The aim of the present study was to explore what factors affect this routine-like task, resulting in fast or slow transfer of objects. A qualitative video study, informed by an observational ethnographic approach, was conducted in a major teaching hospital in the UK. A total of 20 general surgical operations were observed. In total, approximately 68 h of video data have been reviewed. A subsample of 225 min has been analysed in detail using interactional video-analysis developed within the social sciences. Two factors affecting object transfer were observed: (1) relative instrument trolley position and (2) alignment. The scrub nurse's instrument trolley position (close to vs. further back from the surgeon) and alignment (gaze direction) impacts on the communication with the surgeon, and consequently, on the speed of object transfer. When the scrub nurse was standing close to the surgeon, and "converged" to follow the surgeon's movements, the transfer occurred more seamlessly and faster (<1.0 s) than when the scrub nurse was standing further back from the surgeon and did not follow the surgeon's movements (>1.0 s). The smoothness of object transfer can be improved by adjusting the scrub nurse's instrument trolley position, enabling a better monitoring of surgeon's bodily conduct and affording early orientation (awareness) to an upcoming request (changing situation). Object transfer is facilitated by the surgeon's embodied practices, which can elicit the nurse's attention to the request and, as a response, maximise a faster object transfer. A simple intervention to highlight the significance of these factors could improve communication in the operating theatre. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Continuous Flow Hygroscopicity-Resolved Relaxed Eddy Accumulation (Hy-Res REA) Method of Measuring Size-Resolved Sea-Salt Particle Fluxes

    NASA Astrophysics Data System (ADS)

    Meskhidze, N.; Royalty, T. M.; Phillips, B.; Dawson, K. W.; Petters, M. D.; Reed, R.; Weinstein, J.; Hook, D.; Wiener, R.

    2017-12-01

    The accurate representation of aerosols in climate models requires direct ambient measurement of the size- and composition-dependent particle production fluxes. Here we present the design, testing, and analysis of data collected through the first instrument capable of measuring hygroscopicity-based, size-resolved particle fluxes using a continuous-flow Hygroscopicity-Resolved Relaxed Eddy Accumulation (Hy-Res REA) technique. The different components of the instrument were extensively tested inside the US Environmental Protection Agency's Aerosol Test Facility for sea-salt and ammoniums sulfate particle fluxes. The new REA system design does not require particle accumulation, therefore avoids the diffusional wall losses associated with long residence times of particles inside the air collectors of the traditional REA devices. The Hy-Res REA system used in this study includes a 3-D sonic anemometer, two fast-response solenoid valves, two Condensation Particle Counters (CPCs), a Scanning Mobility Particle Sizer (SMPS), and a Hygroscopicity Tandem Differential Mobility Analyzer (HTDMA). A linear relationship was found between the sea-salt particle fluxes measured by eddy covariance and REA techniques, with comparable theoretical (0.34) and measured (0.39) proportionality constants. The sea-salt particle detection limit of the Hy-Res REA flux system is estimated to be 6x105 m-2s-1. For the conditions of ammonium sulfate and sea-salt particles of comparable source strength and location, the continuous-flow Hy-Res REA instrument was able to achieve better than 90% accuracy of measuring the sea-salt particle fluxes. In principle, the instrument can be applied to measure fluxes of particles of variable size and distinct hygroscopic properties (i.e., mineral dust, black carbon, etc.).

  5. The new ATLAS Fast Calorimeter Simulation

    NASA Astrophysics Data System (ADS)

    Schaarschmidt, J.; ATLAS Collaboration

    2017-10-01

    Current and future need for large scale simulated samples motivate the development of reliable fast simulation techniques. The new Fast Calorimeter Simulation is an improved parameterized response of single particles in the ATLAS calorimeter that aims to accurately emulate the key features of the detailed calorimeter response as simulated with Geant4, yet approximately ten times faster. Principal component analysis and machine learning techniques are used to improve the performance and decrease the memory need compared to the current version of the ATLAS Fast Calorimeter Simulation. A prototype of this new Fast Calorimeter Simulation is in development and its integration into the ATLAS simulation infrastructure is ongoing.

  6. Use of a capillary electrophoresis instrument with laser-induced fluorescence detection for DNA quantitation. Comparison of YO-PRO-1 and PicoGreen assays.

    PubMed

    Guillo, Christelle; Ferrance, Jerome P; Landers, James P

    2006-04-28

    Highly selective and sensitive assays are required for detection and quantitation of the small masses of DNA typically encountered in clinical and forensic settings. High detection sensitivity is achieved using fluorescent labeling dyes and detection techniques such as spectrofluorometers, microplate readers and cytometers. This work describes the use of a laser-induced fluorescence (LIF) detector in conjunction with a commercial capillary electrophoresis instrument for DNA quantitation. PicoGreen and YO-PRO-1, two fluorescent DNA labeling dyes, were used to assess the potential of the system for routine DNA analysis. Linearity, reproducibility, sensitivity, limits of detection and quantitation, and sample stability were examined for the two assays. The LIF detector response was found to be linear (R2 > 0.999) and reproducible (RSD < 9%) in both cases. The PicoGreen assay displayed lower limits of detection and quantitation (20 pg and 60 pg, respectively) than the YO-PRO-1 assay (60 pg and 260 pg, respectively). Although a small variation in fluorescence was observed for the DNA/dye complexes over time, quantitation was not significantly affected and the solutions were found to be relatively stable for 80 min. The advantages of the technique include a 4- to 40-fold reduction in the volume of sample required compared to traditional assays, a 2- to 20-fold reduction in the volume of reagents consumed, fast and automated analysis, and low cost (no specific instrumentation required).

  7. Format Effects of Empirically Derived Multiple-Choice versus Free-Response Instruments When Assessing Graphing Abilities

    ERIC Educational Resources Information Center

    Berg, Craig; Boote, Stacy

    2017-01-01

    Prior graphing research has demonstrated that clinical interviews and free-response instruments produce very different results than multiple-choice instruments, indicating potential validity problems when using multiple-choice instruments to assess graphing skills (Berg & Smith in "Science Education," 78(6), 527-554, 1994). Extending…

  8. Extratropical response to Fast and Slow episodes of Madden-Julian Oscillation in observation and using intervention experiments with CFSv2

    NASA Astrophysics Data System (ADS)

    Yadav, P.; Straus, D. M.

    2017-12-01

    The Madden-Julian Oscillation (MJO) is a potential source of predictability in the extratropics in extended range weather forecasting. The nature of MJO is sporadic and therefore, the mid-latitude response may depend on the nature of the MJO event, in particular the phase speed. We discuss the results of our observational and modeling study of mid-latitude circulation response to Fast and Slow MJO episodes using wintertime ERA-Interim reanalysis data and the CFSv2 coupled model of NOAA. The observational study shows that the mid-latitude response to different propagating speeds is not the same. The propagation speed is defined by the time the OLR takes to propagate from phase 3 to phase 6. The mid-latitude response is assessed in terms of composite maps and frequency of occurrence of robust circulation regimes. Fast episode composite anomalies of 500hPa height show a developing Rossby wave in the mid-Pacific with downstream propagation through MJO phases 2- 4. Development of NAO+ teleconnection pattern is stronger in Slow that in Fast MJO episodes, and occurs with a greater time lag after MJO heating is in the Indian Ocean (phase 3). Previous results find an increase in occurrence of NAO- regime following phase 6. We have found that much of this behavior is due to the slow episodes. Based on these observational results, intervention experiments using CFSv2 are designed to better understand the impact of heating/cooling and to estimate mid-latitude response to Fast and Slow MJO episodes. The added heating experiments consist of 31 year reforecasts for December 1 initial conditions from CFS reanalysis (1980-2011) in which the identical MJO evolution of three-dimensional diabatic heating has been added, thus producing fast and slow MJO episodes with well-defined phase speeds. We will discuss the results of these experiments with a focus on understanding the role of phase speed and interference in setting up the response, and to understand the mechanisms that distinguish fast and slow types of response We will also discuss the diagnostics using Predictable Component Analysis to distinguish the signal forced by common diabatic heating signal from noise, and weather regime response to fast and slow MJO using cluster analysis.

  9. Investigation of Response Amplitude Operators for Floating Offshore Wind Turbines: Preprint

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ramachandran, G. K. V.; Robertson, A.; Jonkman, J. M.

    This paper examines the consistency between response amplitude operators (RAOs) computed from WAMIT, a linear frequency-domain tool, to RAOs derived from time-domain computations based on white-noise wave excitation using FAST, a nonlinear aero-hydro-servo-elastic tool. The RAO comparison is first made for a rigid floating wind turbine without wind excitation. The investigation is further extended to examine how these RAOs change for a flexible and operational wind turbine. The RAOs are computed for below-rated, rated, and above-rated wind conditions. The method is applied to a floating wind system composed of the OC3-Hywind spar buoy and NREL 5-MW wind turbine. The responsesmore » are compared between FAST and WAMIT to verify the FAST model and to understand the influence of structural flexibility, aerodynamic damping, control actions, and waves on the system responses. The results show that based on the RAO computation procedure implemented, the WAMIT- and FAST-computed RAOs are similar (as expected) for a rigid turbine subjected to waves only. However, WAMIT is unable to model the excitation from a flexible turbine. Further, the presence of aerodynamic damping decreased the platform surge and pitch responses, as computed by both WAMIT and FAST when wind was included. Additionally, the influence of gyroscopic excitation increased the yaw response, which was captured by both WAMIT and FAST.« less

  10. Financial Responsibilities for Underground Injection Well Owners or Operators

    EPA Pesticide Factsheets

    This page provides information on UIC financial responsibility requirements, qualifying financial instrumentsRoles and responsibilities for operators and UIC Directors UIC Director’s and review procedures for financial responsibility instruments.

  11. FAST: A near-infrared imaging Fabry-Perot spectrometer

    NASA Astrophysics Data System (ADS)

    Krabbe, A.; Rotaciuc, V.; Storey, J. W. V.; Cameron, M.; Blietz, M.; Drapatz, S.; Hofmann, R.; Saemann, G.; Genzel, R.

    1993-12-01

    The near-infrared imaging spectrometer Fabry-Perot Array Spectrometer (FAST) provides a spectral resolution of 1000-2700 over a field of view of approximately 30 x 30 sq arcsec with a plate scale of 0.5-1.0 arcsec/pixel. FAST is based on a SBRC InSb 58 x 62 FPA working at 6 K, yielding a sensitivity 5(sigma), tint = 100 s, K band) of 1.1 x 10-4 erg/s (sq cm) (sr) at R = 1000. As a portable, self-contained instrument FAST has already been successfully deployed at several 2- and 4-m class telescopes. The optical and mechanical design, computer hardware and software control, as well as spectral calibration of the FPI, special treatment of the detectors, and the main data reduction steps are described. The necessity for such a dedicated system in the investigation of line-emission mechanisms in various galactic and extragalactic environments is illustrated by recently obtained results.

  12. The auroral current circuit and field-aligned currents observed by FAST

    NASA Astrophysics Data System (ADS)

    Elphic, R. C.; Bonnell, J. W.; Strangeway, R. J.; Kepko, L.; Ergun, R. E.; McFadden, J. P.; Carlson, C. W.; Peria, W.; Cattell, C. A.; Klumpar, D.; Shelley, E.; Peterson, W.; Moebius, E.; Kistler, L.; Pfaff, R.

    FAST observes signatures of small-scale downward-going current at the edges of the inverted-V regions where the primary (auroral) electrons are found. In the winter pre-midnight auroral zone these downward currents are carried by upward flowing low- and medium-energy (up to several keV) electron beams. FAST instrumentation shows agreement between the current densities inferred from both the electron distributions and gradients in the magnetic field. FAST data taken near apogee (˜4000-km altitude) commonly show downward current magnetic field deflections consistent with the observed upward flux of ˜109 electrons cm-2 s-1, or current densities of several µA m-2. The electron, field-aligned current and electric field signatures indicate the downward currents may be associated with “black aurora” and auroral ionospheric cavities. The field-aligned voltage-current relationship in the downward current region is nonlinear.

  13. The South African Astronomical Observatory instrumentation software architecture and the SHOC instruments

    NASA Astrophysics Data System (ADS)

    van Gend, Carel; Lombaard, Briehan; Sickafoose, Amanda; Whittal, Hamish

    2016-07-01

    Until recently, software for instruments on the smaller telescopes at the South African Astronomical Observatory (SAAO) has not been designed for remote accessibility and frequently has not been developed using modern software best-practice. We describe a software architecture we have implemented for use with new and upgraded instruments at the SAAO. The architecture was designed to allow for multiple components and to be fast, reliable, remotely- operable, support different user interfaces, employ as much non-proprietary software as possible, and to take future-proofing into consideration. Individual component drivers exist as standalone processes, communicating over a network. A controller layer coordinates the various components, and allows a variety of user interfaces to be used. The Sutherland High-speed Optical Cameras (SHOC) instruments incorporate an Andor electron-multiplying CCD camera, a GPS unit for accurate timing and a pair of filter wheels. We have applied the new architecture to the SHOC instruments, with the camera driver developed using Andor's software development kit. We have used this to develop an innovative web-based user-interface to the instrument.

  14. A critical role of fatty acid binding protein 4 and 5 (FABP4/5) in the systemic response to fasting.

    PubMed

    Syamsunarno, Mas Rizky A A; Iso, Tatsuya; Hanaoka, Hirofumi; Yamaguchi, Aiko; Obokata, Masaru; Koitabashi, Norimichi; Goto, Kosaku; Hishiki, Takako; Nagahata, Yoshiko; Matsui, Hiroki; Sano, Motoaki; Kobayashi, Masaki; Kikuchi, Osamu; Sasaki, Tsutomu; Maeda, Kazuhisa; Murakami, Masami; Kitamura, Tadahiro; Suematsu, Makoto; Tsushima, Yoshito; Endo, Keigo; Hotamisligil, Gökhan S; Kurabayashi, Masahiko

    2013-01-01

    During prolonged fasting, fatty acid (FA) released from adipose tissue is a major energy source for peripheral tissues, including the heart, skeletal muscle and liver. We recently showed that FA binding protein 4 (FABP4) and FABP5, which are abundantly expressed in adipocytes and macrophages, are prominently expressed in capillary endothelial cells in the heart and skeletal muscle. In addition, mice deficient for both FABP4 and FABP5 (FABP4/5 DKO mice) exhibited defective uptake of FA with compensatory up-regulation of glucose consumption in these tissues during fasting. Here we showed that deletion of FABP4/5 resulted in a marked perturbation of metabolism in response to prolonged fasting, including hyperketotic hypoglycemia and hepatic steatosis. Blood glucose levels were reduced, whereas the levels of non-esterified FA (NEFA) and ketone bodies were markedly increased during fasting. In addition, the uptake of the (125)I-BMIPP FA analogue in the DKO livers was markedly increased after fasting. Consistent with an increased influx of NEFA into the liver, DKO mice showed marked hepatic steatosis after a 48-hr fast. Although gluconeogenesis was observed shortly after fasting, the substrates for gluconeogenesis were reduced during prolonged fasting, resulting in insufficient gluconeogenesis and enhanced hypoglycemia. These metabolic responses to prolonged fasting in DKO mice were readily reversed by re-feeding. Taken together, these data strongly suggested that a maladaptive response to fasting in DKO mice occurred as a result of an increased influx of NEFA into the liver and pronounced hypoglycemia. Together with our previous study, the metabolic consequence found in the present study is likely to be attributed to an impairment of FA uptake in the heart and skeletal muscle. Thus, our data provided evidence that peripheral uptake of FA via capillary endothelial FABP4/5 is crucial for systemic metabolism and may establish FABP4/5 as potentially novel targets for the modulation of energy homeostasis.

  15. A Critical Role of Fatty Acid Binding Protein 4 and 5 (FABP4/5) in the Systemic Response to Fasting

    PubMed Central

    Syamsunarno, Mas Rizky A. A.; Iso, Tatsuya; Hanaoka, Hirofumi; Yamaguchi, Aiko; Obokata, Masaru; Koitabashi, Norimichi; Goto, Kosaku; Hishiki, Takako; Nagahata, Yoshiko; Matsui, Hiroki; Sano, Motoaki; Kobayashi, Masaki; Kikuchi, Osamu; Sasaki, Tsutomu; Maeda, Kazuhisa; Murakami, Masami; Kitamura, Tadahiro; Suematsu, Makoto; YoshitoTsushima; Endo, Keigo; Hotamisligil, Gökhan S.; Kurabayashi, Masahiko

    2013-01-01

    During prolonged fasting, fatty acid (FA) released from adipose tissue is a major energy source for peripheral tissues, including the heart, skeletal muscle and liver. We recently showed that FA binding protein 4 (FABP4) and FABP5, which are abundantly expressed in adipocytes and macrophages, are prominently expressed in capillary endothelial cells in the heart and skeletal muscle. In addition, mice deficient for both FABP4 and FABP5 (FABP4/5 DKO mice) exhibited defective uptake of FA with compensatory up-regulation of glucose consumption in these tissues during fasting. Here we showed that deletion of FABP4/5 resulted in a marked perturbation of metabolism in response to prolonged fasting, including hyperketotic hypoglycemia and hepatic steatosis. Blood glucose levels were reduced, whereas the levels of non-esterified FA (NEFA) and ketone bodies were markedly increased during fasting. In addition, the uptake of the 125I-BMIPP FA analogue in the DKO livers was markedly increased after fasting. Consistent with an increased influx of NEFA into the liver, DKO mice showed marked hepatic steatosis after a 48-hr fast. Although gluconeogenesis was observed shortly after fasting, the substrates for gluconeogenesis were reduced during prolonged fasting, resulting in insufficient gluconeogenesis and enhanced hypoglycemia. These metabolic responses to prolonged fasting in DKO mice were readily reversed by re-feeding. Taken together, these data strongly suggested that a maladaptive response to fasting in DKO mice occurred as a result of an increased influx of NEFA into the liver and pronounced hypoglycemia. Together with our previous study, the metabolic consequence found in the present study is likely to be attributed to an impairment of FA uptake in the heart and skeletal muscle. Thus, our data provided evidence that peripheral uptake of FA via capillary endothelial FABP4/5 is crucial for systemic metabolism and may establish FABP4/5 as potentially novel targets for the modulation of energy homeostasis. PMID:24244493

  16. 40 CFR 202.20 - Standards for highway operations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) measured on an open site with fast meter response at 50 feet from the centerline of lane of travel on highways with speed limits of 35 MPH or less; or 90 dB(A) measured on an open site with fast meter response..., acceleration or deceleration generates a sound level in excess of 83 dB(A) measured on an open site with fast...

  17. 40 CFR 202.20 - Standards for highway operations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) measured on an open site with fast meter response at 50 feet from the centerline of lane of travel on highways with speed limits of 35 MPH or less; or 90 dB(A) measured on an open site with fast meter response..., acceleration or deceleration generates a sound level in excess of 83 dB(A) measured on an open site with fast...

  18. 40 CFR 202.20 - Standards for highway operations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) measured on an open site with fast meter response at 50 feet from the centerline of lane of travel on highways with speed limits of 35 MPH or less; or 90 dB(A) measured on an open site with fast meter response..., acceleration or deceleration generates a sound level in excess of 83 dB(A) measured on an open site with fast...

  19. 40 CFR 202.20 - Standards for highway operations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) measured on an open site with fast meter response at 50 feet from the centerline of lane of travel on highways with speed limits of 35 MPH or less; or 90 dB(A) measured on an open site with fast meter response..., acceleration or deceleration generates a sound level in excess of 83 dB(A) measured on an open site with fast...

  20. 40 CFR 202.20 - Standards for highway operations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) measured on an open site with fast meter response at 50 feet from the centerline of lane of travel on highways with speed limits of 35 MPH or less; or 90 dB(A) measured on an open site with fast meter response..., acceleration or deceleration generates a sound level in excess of 83 dB(A) measured on an open site with fast...

  1. Aquarius: The Instrument and Initial Results

    NASA Technical Reports Server (NTRS)

    Vine, David M Le; Lagerloef, G.S.E.; Ruf, C.; Wentz, F.; Yueh, S.; Piepmeier, J.; Lindstrom, E.; Dinnat, E.

    2012-01-01

    Aquarius was launched on June 10, 2011 aboard the Aquarius/SAC-D observatory and the instrument has been operating continuously since the initial turned-on was completed on August 25. The initial observed antenna temperatures were close to predicted and the first salinity map was released in September. In order to map the ocean salinity field, Aquarius includes several special features such as the inclusion of a scatterometer to provide a roughness correction, measurement of the third Stokes parameter to correct for Faraday rotation, and fast sampling to mitigate the effects of RFI. This paper provides an overview of the instrument and an example of initial results. Details are covered in subsequent papers in the session on Aquarius

  2. "Data Acquisition Systems"

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Unterweger, Michael; Costrell, Louis deceased

    2009-07-07

    This project involved support for Lou Costrell and myself in the development of IEEE and IEC standards for nuclear counting and data acquisition systems. Over the years, as a result of this support, Lou and I were able to attend standards meetings of IEEE and IEC, which led directly to the publication of many standards for NIM systems, FastBus and CAMAC. We also chaired several writing committees as well as ANSI N42 (Nuclear instrumentation), IEEE NIM (NIM standard), IEEE NID (NPSS nuclear instruments and detector) and IEC TC45 WG9 (Nuclear instrumentation). Through this support we were able to assure thatmore » the interests of the US and DOE were expressed and implemented in the various standards.« less

  3. Real time in situ detection of organic nitrates in atmospheric aerosols

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rollins, Andrew W.; Smith, Jared D.; Wilson, Kevin R.

    2010-06-11

    A new field instrument is described that quantifies total particle phase organic nitrates. The instrument is based on the thermal dissociation laser induced fluorescence (TD-LIF) method that thermally converts nitrates to NO2 which is then detected by LIF. This instrument is unique in its ability to provide fast sensitive measurements of particle phase organic nitrates, without interference from inorganic nitrate. Here we use it to quantify organic nitrates in SOA generated from high-NOx photooxidation of limonene, a-pinene, D-3-carene, and tridecane. In these experiments the organic nitrate moiety is observed to be 6-15percent of the total SOA mass, depending on themore » organic precursor.« less

  4. Characterizing a fast-response, low-afterglow liquid scintillator for neutron time-of-flight diagnostics in fast ignition experiments.

    PubMed

    Abe, Y; Hosoda, H; Arikawa, Y; Nagai, T; Kojima, S; Sakata, S; Inoue, H; Iwasa, Y; Iwano, K; Yamanoi, K; Fujioka, S; Nakai, M; Sarukura, N; Shiraga, H; Norimatsu, T; Azechi, H

    2014-11-01

    The characteristics of oxygen-enriched liquid scintillators with very low afterglow are investigated and optimized for application to a single-hit neutron spectrometer for fast ignition experiments. It is found that 1,2,4-trimethylbenzene has better characteristics as a liquid scintillator solvent than the conventional solvent, p-xylene. In addition, a benzophenon-doped BBQ liquid scintillator is shown to demonstrate very rapid time response, and therefore has potential for further use in neutron diagnostics with fast time resolution.

  5. Development of a Flight Instrument Package

    DTIC Science & Technology

    1992-12-01

    105 0 F 80 to 130°F 95 to 145-F Recommended Maximum Intermittent 180-F 180°F 180 F ISODAl P Velocity-Sensitive Compression ResistanceE-A-R ISODAMP C...PARnAMETER *Too". CONDIIONSo m 1W EAX ON ?" MAX UNIT* Input Iiaa6-iag al - 10 25 - 20 s0 iov vs-OPES ei sta fast Avoomii (NOW 1) - 0.2 - - 0.2 - b.V...to the supply pin is also importanft particularly over fast . contributing to the operational amplifier’s high temperature, since many types of

  6. Technology Transition and Adoption: A Study in Search of Metrics for Evaluating Transition

    DTIC Science & Technology

    2010-12-01

    Coalitions and Agents Project (Fast C2AP) 3 Direct Thermal to Electric Conversion (DTEC) 3 High-Frequency Active Auroral Project ( HAARP ) Instrument...which the technology is disruptive: 40 RAID TEAM SDS M&DC2 LCCMD DTEC AT3 WASP DOTS LASER Boomerang Virtual Autopsy  Program HAARP PCES Ultralog Sticky...RAID SDS Fast C2AP DTEC AT3 WASP Radar Scope DOTS SPEYES LASER Boomerang MAV ACTD HAARP TEAM PCES Ultralog Sticky Flare Active Templates LCCMD VIVID

  7. Digitizing the ranges

    NASA Astrophysics Data System (ADS)

    Haddleton, Graham P.

    2001-04-01

    In military research and development or testing there are various fast and dangerous events that need to be recorded and analyzed. High-speed cameras allow the capture of movement too fast to be recognized by the human eye, and provide data that is essential for the analysis and evaluation of such events. High-speed photography is often the only type of instrumentation that can be used to record the parameters demanded by our customers. I will show examples where this applied cinematography is used not only to provide a visual record of events, but also as an essential measurement tool.

  8. Stripline fast faraday cup for measuring GHz structure of ion beams

    DOEpatents

    Bogaty, John M.

    1992-01-01

    The Stripline Fast Faraday Cup is a device which is used to quantitatively and qualitatively measure gigahertz time structure characteristics of ion beams with energies up to at least 30 Mev per nucleon. A stripline geometry is employed in conjunction with an electrostatic screen and a Faraday cup to provide for analysis of the structural characteristics of an ion beam. The stripline geometry allows for a large reduction in the size of the instrument while the electrostatic screen permits measurements of the properties associated with low speed ion beams.

  9. A fast RCS accuracy assessment method for passive radar calibrators

    NASA Astrophysics Data System (ADS)

    Zhou, Yongsheng; Li, Chuanrong; Tang, Lingli; Ma, Lingling; Liu, QI

    2016-10-01

    In microwave radar radiometric calibration, the corner reflector acts as the standard reference target but its structure is usually deformed during the transportation and installation, or deformed by wind and gravity while permanently installed outdoor, which will decrease the RCS accuracy and therefore the radiometric calibration accuracy. A fast RCS accuracy measurement method based on 3-D measuring instrument and RCS simulation was proposed in this paper for tracking the characteristic variation of the corner reflector. In the first step, RCS simulation algorithm was selected and its simulation accuracy was assessed. In the second step, the 3-D measuring instrument was selected and its measuring accuracy was evaluated. Once the accuracy of the selected RCS simulation algorithm and 3-D measuring instrument was satisfied for the RCS accuracy assessment, the 3-D structure of the corner reflector would be obtained by the 3-D measuring instrument, and then the RCSs of the obtained 3-D structure and corresponding ideal structure would be calculated respectively based on the selected RCS simulation algorithm. The final RCS accuracy was the absolute difference of the two RCS calculation results. The advantage of the proposed method was that it could be applied outdoor easily, avoiding the correlation among the plate edge length error, plate orthogonality error, plate curvature error. The accuracy of this method is higher than the method using distortion equation. In the end of the paper, a measurement example was presented in order to show the performance of the proposed method.

  10. Fast parallel tandem mass spectral library searching using GPU hardware acceleration.

    PubMed

    Baumgardner, Lydia Ashleigh; Shanmugam, Avinash Kumar; Lam, Henry; Eng, Jimmy K; Martin, Daniel B

    2011-06-03

    Mass spectrometry-based proteomics is a maturing discipline of biologic research that is experiencing substantial growth. Instrumentation has steadily improved over time with the advent of faster and more sensitive instruments collecting ever larger data files. Consequently, the computational process of matching a peptide fragmentation pattern to its sequence, traditionally accomplished by sequence database searching and more recently also by spectral library searching, has become a bottleneck in many mass spectrometry experiments. In both of these methods, the main rate-limiting step is the comparison of an acquired spectrum with all potential matches from a spectral library or sequence database. This is a highly parallelizable process because the core computational element can be represented as a simple but arithmetically intense multiplication of two vectors. In this paper, we present a proof of concept project taking advantage of the massively parallel computing available on graphics processing units (GPUs) to distribute and accelerate the process of spectral assignment using spectral library searching. This program, which we have named FastPaSS (for Fast Parallelized Spectral Searching), is implemented in CUDA (Compute Unified Device Architecture) from NVIDIA, which allows direct access to the processors in an NVIDIA GPU. Our efforts demonstrate the feasibility of GPU computing for spectral assignment, through implementation of the validated spectral searching algorithm SpectraST in the CUDA environment.

  11. Hepatic insulin-like growth-factor binding protein (igfbp) responses tofood restriction in Atlantic salmon smolts

    USGS Publications Warehouse

    Breves, Jason P.; Phipps-Costin, Silas K.; Fujimoto, Chelsea K.; Einarsdottir, Ingibjörg E.; Regish, Amy M.; Björnsson, Björn Thrandur; McCormick, Stephen

    2016-01-01

    The growth hormone (Gh)/insulin-like growth-factor (Igf) system plays a central role in the regulation of growth in fishes. However, the roles of Igf binding proteins (Igfbps) in coordinating responses to food availability are unresolved, especially in anadromous fishes preparing for seaward migration. We assayed plasma Gh, Igf1, thyroid hormones and cortisol along with igfbp mRNA levels in fasted and fed Atlantic salmon ( Salmo salar ). Fish were fasted for 3 or 10 days near the peak of smoltification (late April to early May). Fasting reduced plasma glucose by 3 days and condition factor by 10 days. Plasma Gh, cortisol, and thyroxine (T 4 ) were not altered in response to fasting, whereas Igf1 and 3,5,3′-triiodo- l -thyronine (T 3 ) were slightly higher and lower than controls, respectively. Hepatic igfbp1b1 , - 1b2 , - 2a , - 2b1 and - 2b2 mRNA levels were not responsive to fasting, but there were marked increases in igfbp1a1 following 3 and 10 days of fasting. Fasting did not alter hepatic igf1or igf2 ; however, muscle igf1 was diminished by 10 days of fasting. There were no signs that fasting compromised branchial ionoregulatory functions, as indicated by unchanged Na + /K + -ATPase activity and ion pump/transporter mRNA levels. We conclude that dynamic hepatic igfbp1a1 and muscle igf1 expression participate in the modulation of Gh/Igf signaling in smolts undergoing catabolism.

  12. Comparison of measurement data at the impeller exit of a centrifugal compressor measured with both pneumatic and fast-response probes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roduner, C.; Koeppel, P.; Kupferschmied, P.

    1999-07-01

    The main goal of these investigations was the refined measurement of unsteady high speed flow in a centrifugal compressor using the advanced FRAP{reg_sign} fast-response aerodynamic probe system. The present contribution focuses on the impeller exit region and shows critical comparisons between fast-response (time-resolving) and conventional pneumatic probe measurement results. Three probes of identical geometry (one fast and two pneumatic) were used to perform wall-to-wall traverses close to impeller exit. The data shown refer to a single running condition near the best point of the stage. The mass flow obtained from different probe measurements and from the standard orifice measurement weremore » compared. Stage work obtained from temperature rise measured with a FRAP{reg_sign} probe and from impeller outlet velocity vectors fields by using Euler`s turbine equation are presented. The comparison in terms of velocity magnitude and angle distribution is quite satisfactory, indicating the superior DC measurement capabilities of the fast-response probe system.« less

  13. The sound of music: differentiating musicians using a fast, musical multi-feature mismatch negativity paradigm.

    PubMed

    Vuust, Peter; Brattico, Elvira; Seppänen, Miia; Näätänen, Risto; Tervaniemi, Mari

    2012-06-01

    Musicians' skills in auditory processing depend highly on instrument, performance practice, and on level of expertise. Yet, it is not known though whether the style/genre of music might shape auditory processing in the brains of musicians. Here, we aimed at tackling the role of musical style/genre on modulating neural and behavioral responses to changes in musical features. Using a novel, fast and musical sounding multi-feature paradigm, we measured the mismatch negativity (MMN), a pre-attentive brain response, to six types of musical feature change in musicians playing three distinct styles of music (classical, jazz, rock/pop) and in non-musicians. Jazz and classical musicians scored higher in the musical aptitude test than band musicians and non-musicians, especially with regards to tonal abilities. These results were extended by the MMN findings: jazz musicians had larger MMN-amplitude than all other experimental groups across the six different sound features, indicating a greater overall sensitivity to auditory outliers. In particular, we found enhanced processing of pith and sliding up to pitches in jazz musicians only. Furthermore, we observed a more frontal MMN to pitch and location compared to the other deviants in jazz musicians and left lateralization of the MMN to timbre in classical musicians. These findings indicate that the characteristics of the style/genre of music played by musicians influence their perceptual skills and the brain processing of sound features embedded in a musical context. Musicians' brain is hence shaped by the type of training, musical style/genre, and listening experiences. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Antonelli, M., E-mail: matias.antonelli@elettra.eu; Cautero, G.; Sergo, R.

    The recent evolution of free-electron lasers has not been matched by the development of adequate beam-monitoring instrumentation. However, for both experimental and diagnostics purposes, it is crucial to keep such photon beams under control, avoiding at the same time the absorption of the beam and the possible destruction of the detector. These requirements can be fulfilled by utilizing fast and non-invasive photon detectors operated in situ, upstream from the experimental station. From this perspective, sensors based on Quantum Well (QW) devices can be the key to detecting ultra-short light pulses. In fact, owing to their high electron mobility, InGaAs/InAlAs QWmore » devices operated at room temperature exhibit sub-nanosecond response times. Their direct, low-energy band gap renders them capable of detecting photons ranging from visible to X-ray. Furthermore, the 2D electron gas forming inside the QW is responsible for a charge amplification mechanism, which increases the charge collection efficiency of these devices. In order to acquire the signals produced by these QW sensors, a novel readout electronics has been developed. It is based on a high-speed charge integrator, which allows short, low-intensity current pulses to be read within a 50-ns window. The integrated signal is acquired through an ADC and the entire process can be performed at a 10-MHz repetition rate. This work provides a detailed description of the development of the QW detectors and the acquisition electronics, as well as reporting the main experimental results, which show how these tools are well suited for the realization of fast, broad-band beam monitors.« less

  15. Fast and Slow Responses of the South Asian Monsoon System to Anthropogenic Aerosols

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ganguly, Dilip; Rasch, Philip J.; Wang, Hailong

    2012-09-25

    Using a global climate model with fully predictive aerosol life cycle, we investigate the fast and slow responses of the South Asian monsoon system to anthropogenic aerosol forcing. Our results show that the feedbacks associated with sea surface temperature (SST) change caused by aerosols play a more important role than the aerosol's direct impact on radiation, clouds and land surface (rapid adjustments) in shaping the total equilibrium climate response of the monsoon system to aerosol forcing. Inhomogeneous SST cooling caused by anthropogenic aerosols eventually reduces the meridional tropospheric temperature gradient and the easterly shear of zonal winds over the region,more » slowing down the local Hadley cell circulation, decreasing the northward moisture transport, and causing a reduction in precipitation over South Asia. Although total responses in precipitation are closer to the slow responses in general, the fast component dominates over land areas north of 25°N. Our results also show an east-west asymmetry in the fast responses to anthropogenic aerosols causing increases in precipitation west of 80°E but decreases east of it.« less

  16. Ni: Fe2O3, Mg: Fe2O3 and Fe2O3 thin films gas sensor application

    NASA Astrophysics Data System (ADS)

    Saritas, Sevda; Kundakci, Mutlu; Coban, Omer; Tuzemen, Sebahattin; Yildirim, Muhammet

    2018-07-01

    Iron oxide is a widely used sensitive material for gas sensor applications. They have fascinated much attention in the field of gas sensing and detecting under atmospheric conditions and at 200 °C temperature due to their low cost in production; simplicity and fast of their use; large number of detectable gases. Iron oxide gas sensors constitute investigated for hazardous gases used in various fields. The morphological structure (particle size, pore size, etc.), optical, magnetic and electrical properties of Ni:Fe2O3, Mg:Fe2O3 and Fe2O3 thin films which grown by Spray pyrolysis (SP) have been investigated. XRD, Raman and AFM techniques have been used for structural analysis. AFM measurements have been provided very useful information about surface topography. I-V (Van der Pauw) technique has been used for response of gas sensor. These devices offer a wide variety of advantages over traditional analytical instruments such as low cost, short response time, easy manufacturing, and small size.

  17. Testing of a sCVD diamond detection system in the CROCUS reactor

    NASA Astrophysics Data System (ADS)

    Hursin, M.; Weiss, C.; Frajtag, P.; Lamirand, V.; Perret, G.; Kavrigin, P.; Pautz, A.; Griesmayer, E.

    2018-05-01

    The paper describes the testing of the NEUTON detection system into CROCUS, the zero-power reactor of the École Polytechnique Fédérale de Lausanne (EPFL). NEUTON is composed of a 4 mm × 4 mm sCVD diamond detector with a 6Li converter and the associated acquisition electronics. It is developed by CIVIDEC Instrumentation GmbH. The use of a diamond detector with converter in the mixed radiation field of a nuclear reactor is challenging because these detectors are sensitive to gamma-rays, fast neutrons and thermal neutrons through conversion in 6Li . In NEUTON, the rejection of gamma-rays is achieved in real time, via the analysis of the signal pulse shape from the detector. To do so, a few signal characteristics (amplitude, area and FWHM) are recorded in the integrated Field Programmable Gate Arrays (FPGA) of the system. This treatment does not induce any dead time. Measurements in CROCUS demonstrated for the first time the capability of a system like NEUTON to detect and separate fast neutrons, thermal neutrons, and gamma-rays. The system response was shown to be linear with respect to the reactor power (up to 35W) and its thermal sensitivity was found to be (3.5± 0.2)× 10^{-5} cps/nv.

  18. Monoterpene separation by coupling proton transfer reaction time-of-flight mass spectrometry with fastGC.

    PubMed

    Materić, Dušan; Lanza, Matteo; Sulzer, Philipp; Herbig, Jens; Bruhn, Dan; Turner, Claire; Mason, Nigel; Gauci, Vincent

    2015-10-01

    Proton transfer reaction mass spectrometry (PTR-MS) is a well-established technique for real-time analysis of volatile organic compounds (VOCs). Although it is extremely sensitive (with sensitivities of up to 4500 cps/ppbv, limits of detection <1 pptv and the response times of approximately 100 ms), the selectivity of PTR-MS is still somewhat limited, as isomers cannot be separated. Recently, selectivity-enhancing measures, such as manipulation of drift tube parameters (reduced electric field strength) and using primary ions other than H3O(+), such as NO(+) and O2 (+), have been introduced. However, monoterpenes, which belong to the most important plant VOCs, still cannot be distinguished so more traditional technologies, such as gas chromatography mass spectrometry (GC-MS), have to be utilised. GC-MS is very time consuming (up to 1 h) and cannot be used for real-time analysis. Here, we introduce a sensitive, near-to-real-time method for plant monoterpene research-PTR-MS coupled with fastGC. We successfully separated and identified six of the most abundant monoterpenes in plant studies (α- and β-pinenes, limonene, 3-carene, camphene and myrcene) in less than 80 s, using both standards and conifer branch enclosures (Norway spruce, Scots pine and black pine). Five monoterpenes usually present in Norway spruce samples with a high abundance were separated even when the compound concentrations were diluted to 20 ppbv. Thus, fastGC-PTR-ToF-MS was shown to be an adequate one-instrument solution for plant monoterpene research.

  19. Stress matters! Psychophysiological and emotional loadings of pregnant women undergoing fetal magnetic resonance imaging.

    PubMed

    Derntl, Birgit; Krajnik, Jacqueline; Kollndorfer, Kathrin; Bijak, Manfred; Nemec, Ursula; Leithner, Katharina; Prayer, Daniela; Schöpf, Veronika

    2015-02-13

    While the application of fetal MRI in high-risk pregnant women is steadily rising, little is known about the psychological consequences of this procedure. The aim of the present study was to investigate emotional and psychophysiological reactions of females undergoing fetal MRI. Sixty women (17-44 ys), assigned for fetal MRI, were included. Affective state was assessed by standardized measures of anxiety, emotional states and depressive symptoms. Stress coping strategies were assessed using a self-report questionnaire. Stress responses were determined using skin conductance levels (SCL) during fetal MRI as well as measurement of salivary cortisol levels immediately before and after fetal MRI. Analysis of fast and slow physiological stress measures revealed significant differences between women with and without a supporting person accompanying them to the examination. For SCLs, lower levels of stress during MRI emerged in accompanied women. Women with well-marked stress-coping-strategies experienced lower levels of stress during the examination. Although fast and slow stress measures before and after MRI did not show significant correlations, a significant difference of SCLs pre and post examination was clearly detectable, as well as a trend of decreased cortisol levels for both time points. The results imply that the elevation of SCLs is an accurate instrument to assess fast stress alterations in patients during fetal MRI. Stress coping strategies and whether women are accompanied or not play an important role in the experience of anxiety and depressive symptoms. These factors should be considered especially in patients with high-risk-pregnancies to improve patient care.

  20. The assessment of pore connectivity in hierarchical zeolites using positron annihilation lifetime spectroscopy: instrumental and morphological aspects.

    PubMed

    Zubiaga, Asier; Warringham, Robbie; Boltz, Marilyne; Cooke, David; Crivelli, Paolo; Gidley, David; Pérez-Ramírez, Javier; Mitchell, Sharon

    2016-04-07

    Recent studies demonstrated the power of positron annihilation lifetime spectroscopy (PALS) to characterise the connectivity and corresponding effectiveness of hierarchical pore networks in zeolites. This was based on the fractional escape of ortho-positronium (Ps), formed within the micropore framework, to vacuum. To further develop this technique, here we assess the impact of the positron implantation energy and of the zeolite crystal size and the particle morphology. Conventional measurements using fast positrons and beam measurements applying moderated positrons both readily distinguish purely microporous ZSM-5 zeolites comprised of single crystals or crystal aggregates. Unlike beam measurements, however, conventional measurements fail to discriminate model hierarchical zeolites with open or constricted mesopore architectures. Several steps are taken to rationalise these observations. The dominant contribution of Ps diffusion to the PALS response is confirmed by capping the external surface of the zeolite crystals with tetraethylorthosilicate, which greatly enhances the sensitivity to the micropore network. A one-dimensional model is constructed to predict the out-diffusion of Ps from a zeolite crystal, which is validated experimentally by comparing coffin-shaped single crystals of varying size. Calculation of the trends expected on the application of fast or moderated positrons indicates that the distinctions in the initial distribution of Ps at the crystal level cannot explain the limited sensitivity of the former to the mesopore architecture. Instead, we propose that the greater penetration of fast positrons within the sample increases the probability of Ps re-entry from intercrystalline voids into mesopores connected with the external surface of zeolite crystals, thereby reducing their fractional escape.

  1. Electro-optic deflectors deliver advantages over acousto-optical deflectors in a high resolution, ultra-fast force-clamp optical trap.

    PubMed

    Woody, Michael S; Capitanio, Marco; Ostap, E Michael; Goldman, Yale E

    2018-04-30

    We characterized experimental artifacts arising from the non-linear response of acousto-optical deflectors (AODs) in an ultra-fast force-clamp optical trap and have shown that using electro-optical deflectors (EODs) instead eliminates these artifacts. We give an example of the effects of these artifacts in our ultra-fast force clamp studies of the interaction of myosin with actin filaments. The experimental setup, based on the concept of Capitanio et al. [Nat. Methods 9, 1013-1019 (2012)] utilizes a bead-actin-bead dumbbell held in two force-clamped optical traps which apply a load to the dumbbell to move it at a constant velocity. When myosin binds to actin, the filament motion stops quickly as the total force from the optical traps is transferred to the actomyosin attachment. We found that in our setup, AODs were unsuitable for beam steering due to non-linear variations in beam intensity and deflection angle as a function of driving frequency, likely caused by low-amplitude standing acoustic waves in the deflectors. These aberrations caused instability in the force feedback loops leading to artifactual jumps in the trap position. We demonstrate that beam steering with EODs improves the performance of our instrument. Combining the superior beam-steering capability of the EODs, force acquisition via back-focal-plane interferometry, and dual high-speed FPGA-based feedback loops, we apply precise and constant loads to study the dynamics of interactions between actin and myosin. The same concept applies to studies of other biomolecular interactions.

  2. Sonic flow distortion experiment

    NASA Astrophysics Data System (ADS)

    Peters, Gerhard; Kirtzel, Hans-Jürgen; Radke, Jürgen

    2017-04-01

    We will present results from a field experiment with multiple sonic anemometers, and will address the question about residual errors of wind tunnel based calibrations that are transferred to atmospheric measurements. Ultrasonic anemometers have become standard components of high quality in-situ instrumentations, because of the long term calibration stability, fast response, wide dynamic range, and various options of built in quality control. On the downside of this technology is the fact that the sound transducers and the carrying structure represent obstacles in the flow causing systematic deviations of the measured flow from the free flow. Usually, the correction schemes are based on wind tunnel observations of the sonic-response as function of angle of attack under stationary conditions. Since the natural atmospheric flow shows turbulence intensities and scales, which cannot be mimicked in a wind tunnel, it is suspected that the wind-tunnel based corrections may be not (fully) applicable to field data. The wide spread use of sonic anemometers in eddy flux instrumentations for example in the frame of EuroFlux, AmeriFlux or other international observation programs has therefore prompted a - still controversial - discussion of the significance of residual flow errors. In an attempt to quantify the flow distortion in free field conditions, 12 identical 3-component sonics with 120 degree head symmetry were operated at the north margin of an abandoned airfield. The sonics were installed in a straight line in WE-direction at 2.6 m height with a mutual distance of 3 meters and with an azimuth increment of the individual sonics of 11 degrees. Synchronous raw data were recorded with 20 Hz sample rate. Data of about 12 hours with southerly winds (from the relatively flat airfield) were analyzed. Statistical homogeneity of the wind field in the range of the instruments line was assumed, but a variable finite turbulent decay constant was accounted for, which was estimated from the data. The free field flow distortion estimates will be discussed in comparison with wind tunnel observations.

  3. Fasting mediated increase in p-BAD(ser155) and p-AKT(ser473) in the prefrontal cortex of mice.

    PubMed

    Pitchaimani, Vigneshwaran; Arumugam, Somasundaram; Thandavarayan, Rajarajan Amirthalingam; Karuppagounder, Vengadeshprabhu; Sreedhar, Remya; Afrin, Rejina; Harima, Meilei; Suzuki, Hiroshi; Miyashita, Shizuka; Nomoto, Mayumi; Sone, Hirohito; Suzuki, Kenji; Watanabe, Kenichi

    2014-09-05

    BAD-deficient mice and fasting have several common functional roles in seizures, beta-hydroxybutyrate (BHB) uptake in brain and alteration in counterregulatory hormonal regulation during hypoglycemia. Neuronal specific insulin receptor knockout (NIRKO) mice display impaired counterregulatory hormonal responses during hypoglycemia. In this study we investigated the fasting mediated expression of p-BAD(ser155) and p-AKT(ser473) in different regions of brain (prefrontal cortex, hippocampus, midbrain and hypothalamus). Fasting specifically increases p-BAD(ser155) and p-AKT(ser473) in prefrontal cortex and decreases in other regions of brain. Our results suggest that fasting may increase the uptake BHB by decreasing p-BAD(ser155) in the brain during hypoglycemia except prefrontal cortex and it uncovers specific functional area of p-BAD(ser155) and p-AKT(ser473) that may regulates counter regulatory hormonal response. Overall in support with previous findings, fasting mediated hypoglycemia activates prefrontal cortex insulin signaling which influences the hypothalamic paraventricular nucleus mediated activation of sympathoadrenal hormonal responses. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. Fast Solar Polarimeter: First Light Results

    NASA Astrophysics Data System (ADS)

    Krishnappa, N.; Feller, A.; Iglesia, F. A.; Solanki, S.

    2013-12-01

    Accurate measurements of magnetic fields on the Sun are crucial to understand various physical processes that take place in the solar atmosphere such as solar eruptions, coronal heating, solar wind acceleration, etc. The Fast Solar Polarimeter (FSP) is a new instrument that is being developed to probe magnetic fields on the Sun. One of the main goals of this polarimeter is to carry out high precision spectropolarimetric observations with spatial resolution close to the telescope diffraction limit. The polarimeter is based on pnCCD technology with split frame transfer and simultaneous multi-channel readout, resulting in frame rate upto 1 kHz. The FSP prototype instrument uses a small format pnCCD of 264x264 pixels which has been developed by PNSensor and by the semiconductor lab of the Max Planck Society. The polarization modulator is based on two ferro-electric liquid crystals (FLCs) interlaced between two static retarders. The first solar observations have been carried out with this prototype during May-June, 2013 at German Vacuum Tower Telescope (VTT) on Tenerife, Canary Islands, Spain. Here we present the instrument performance assessments and the first results on the magnetic field measurements. Further, we briefly discuss about the next phase of FSP which will be a dual beam system with 1k x 1k CCDs.

  5. A Versatile High Speed 250 MHz Pulse Imager for Biomedical Applications

    PubMed Central

    Epel, Boris; Sundramoorthy, Subramanian V.; Mailer, Colin; Halpern, Howard J.

    2009-01-01

    A versatile 250 MHz pulse electron paramagnetic resonance (EPR) instrument for imaging of small animals is presented. Flexible design of the imager hardware and software makes it possible to use virtually any pulse EPR imaging modality. A fast pulse generation and data acquisition system based on general purpose PCI boards performs measurements with minimal additional delays. Careful design of receiver protection circuitry allowed us to achieve very high sensitivity of the instrument. In this article we demonstrate the ability of the instrument to obtain three dimensional images using the electron spin echo (ESE) and single point imaging (SPI) methods. In a phantom that contains a 1 mM solution of narrow line (16 μT, peak-to-peak) paramagnetic spin probe we achieved an acquisition time of 32 seconds per image with a fast 3D ESE imaging protocol. Using an 18 minute 3D phase relaxation (T2e) ESE imaging protocol in a homogeneous sample a spatial resolution of 1.4 mm and a standard deviation of T2e of 8.5% were achieved. When applied to in vivo imaging this precision of T2e determination would be equivalent to 2 torr resolution of oxygen partial pressure in animal tissues. PMID:19924261

  6. A multi-frequency impedance analysing instrument for eddy current testing

    NASA Astrophysics Data System (ADS)

    Yin, W.; Dickinson, S. J.; Peyton, A. J.

    2006-02-01

    This paper presents the design of a high-performance multi-frequency impedance analysing instrument (MFIA) for eddy current testing which has been developed primarily for monitoring a steel production process using an inductive sensor. The system consists of a flexible multi-frequency waveform generator and a voltage/current measurement unit. The impedance of the sensor is obtained by cross-spectral analysis of the current and voltage signals. The system contains high-speed digital-to-analogue, analogue-to-digital converters and dual DSPs with one for control and interface and one dedicated to frequency-spectra analysis using fast Fourier transformation (FFT). The frequency span of the signal that can be analysed ranges from 1 kHz to 8 MHz. The system also employs a high-speed serial port interface (USB) to communicate with a personal computer (PC) and to allow for fast transmission of data and control commands. Overall, the system is capable of delivering over 250 impedance spectra per second. Although the instrument has been developed mainly for use with an inductive sensor, the system is not restricted to inductive measurement. The flexibility of the design architecture is demonstrated with capacitive and resistive measurements by using appropriate input circuitry. Issues relating to optimizing the phase of the spectra components in the excitation waveform are also discussed.

  7. Principal Component-Based Radiative Transfer Model (PCRTM) for Hyperspectral Sensors. Part I; Theoretical Concept

    NASA Technical Reports Server (NTRS)

    Liu, Xu; Smith, William L.; Zhou, Daniel K.; Larar, Allen

    2005-01-01

    Modern infrared satellite sensors such as Atmospheric Infrared Sounder (AIRS), Cosmic Ray Isotope Spectrometer (CrIS), Thermal Emission Spectrometer (TES), Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) and Infrared Atmospheric Sounding Interferometer (IASI) are capable of providing high spatial and spectral resolution infrared spectra. To fully exploit the vast amount of spectral information from these instruments, super fast radiative transfer models are needed. This paper presents a novel radiative transfer model based on principal component analysis. Instead of predicting channel radiance or transmittance spectra directly, the Principal Component-based Radiative Transfer Model (PCRTM) predicts the Principal Component (PC) scores of these quantities. This prediction ability leads to significant savings in computational time. The parameterization of the PCRTM model is derived from properties of PC scores and instrument line shape functions. The PCRTM is very accurate and flexible. Due to its high speed and compressed spectral information format, it has great potential for super fast one-dimensional physical retrievals and for Numerical Weather Prediction (NWP) large volume radiance data assimilation applications. The model has been successfully developed for the National Polar-orbiting Operational Environmental Satellite System Airborne Sounder Testbed - Interferometer (NAST-I) and AIRS instruments. The PCRTM model performs monochromatic radiative transfer calculations and is able to include multiple scattering calculations to account for clouds and aerosols.

  8. Fast Imaging Solar Spectrograph System in New Solar Telescope

    NASA Astrophysics Data System (ADS)

    Park, Y.-D.; Kim, Y. H.; Chae, J.; Goode, P. R.; Cho, K. S.; Park, H. M.; Nah, J. K.; Jang, B. H.

    2010-12-01

    In 2004, Big Bear Solar Observatory in California, USA launched a project for construction of the world's largest aperture solar telescope (D = 1.6m) called New Solar Telescope(NST). University of Hawaii (UH) and Korea Astronomy and Space Science Institute(KASI) partly collaborate on the project. NST is a designed off-axis parabolic Gregorian reflector with very high spatial resolution(0.07 arcsec at 5000A) and is equipped with several scientific instruments such as Visible Imaging Magnetograph (VIM), InfraRed Imaging Magnetograph IRIM), and so on. Since these scientific instruments are focused on studies of the solar photosphere, we need a post-focus instrument for the NST to study the fine structures and dynamic patterns of the solar chromosphere and low Transition Region (TR) layer, including filaments/prominences, spicules, jets, micro flares, etc. For this reason, we developed and installed a fast imaging solar spectrograph(FISS) system on the NST withadvantages of achieving compact design with high spectral resolution and small aberration as well as recording many solar spectral lines in a single and/or dual band mode. FISS was installed in May, 2010 and now we carry out a test observation. In this talk, we introduce the FISS system and the results of the test observation after FISS installation.

  9. Study of neutron shielding collimators for curved beamlines at the European Spallation Source

    NASA Astrophysics Data System (ADS)

    Santoro, V.; DiJulio, D. D.; Ansell, S.; Cherkashyna, N.; Muhrer, G.; Bentley, P. M.

    2018-06-01

    The European Spallation Source is being constructed in Lund, Sweden and is planned to be the world’s brightest pulsed spallation neutron source for cold and thermal neutron beams (≤ 1 eV). The facility uses a 2 GeV proton beam to produce neutrons from a tungsten target. The neutrons are then moderated in a moderator assembly consisting of both liquid hydrogen and water compartments. Surrounding the moderator are 22 beamports, which view the moderator’s outside surfaces. The beamports are connected to long neutron guides that transport the moderated neutrons to the sample position via reflections. As well as the desired moderated neutrons, fast neutrons coming directly from the target can find their way down the beamlines. These can create unwanted sources of background for the instruments. To mitigate such a kind of background, several instruments will use curved guides to lose direct line-of-sight (LoS) to the moderator and the target. In addition instruments can also use shielding collimators to reduce the amount of fast neutrons further traveling down the guide due to albedo reflections or streaming. Several different materials have been proposed for this purpose. We present the results of a study of different options for collimators and identify the optimal choices that balance cost, background and activation levels.

  10. Hodoscope Cineradiography Of Nuclear Fuel Destruction Experiments

    NASA Astrophysics Data System (ADS)

    De Volpi, A.

    1983-08-01

    Nuclear reactor safety studies have applied cineradiographic techniques to achieve key information regarding the durability of fuel elements that are subjected to destructive transients in test reactors. Beginning with its development in 1963, the fast-neutron hodoscope has recorded data at the TREAT reactor in the United States of America. Consisting of a collimator instrumented with several hundred parallel channels of detectors and associated instrumentation, the hodoscope measures fuel motion that takes place within thick-walled steel test containers. Fuel movement is determined by detecting the emission of fast neutrons induced in the test capsule by bursts of the test reactor that last from 0.3 to 30 s. The system has been designed so as to achieve under certain typical conditions( horizontal) spatial resolution less than lmm, time resolution close to lms, mass resolution below 0.1 g, with adequate dynamic range and recording duration. A variety of imaging forms have been developed to display the results of processing and analyzing recorded data.*

  11. A Survey of Modes of Student Response Indicative of Musical Learning in Elementary Instrumental Music.

    ERIC Educational Resources Information Center

    Weaver, Molly A.

    This master's thesis reports on a study of the frequency and modes of student responses that demonstrate musical learning in the elementary instrumental music class. Some advances must be made toward more definitive evaluation practices in elementary school instrumental music if instrumental programs are to be justified in terms of improved…

  12. Ghrelin mimics fasting to enhance human hedonic, orbitofrontal cortex, and hippocampal responses to food.

    PubMed

    Goldstone, Anthony P; Prechtl, Christina G; Scholtz, Samantha; Miras, Alexander D; Chhina, Navpreet; Durighel, Giuliana; Deliran, Seyedeh S; Beckmann, Christian; Ghatei, Mohammad A; Ashby, Damien R; Waldman, Adam D; Gaylinn, Bruce D; Thorner, Michael O; Frost, Gary S; Bloom, Stephen R; Bell, Jimmy D

    2014-06-01

    Ghrelin, which is a stomach-derived hormone, increases with fasting and energy restriction and may influence eating behaviors through brain hedonic reward-cognitive systems. Therefore, changes in plasma ghrelin might mediate counter-regulatory responses to a negative energy balance through changes in food hedonics. We investigated whether ghrelin administration (exogenous hyperghrelinemia) mimics effects of fasting (endogenous hyperghrelinemia) on the hedonic response and activation of brain-reward systems to food. In a crossover design, 22 healthy, nonobese adults (17 men) underwent a functional magnetic resonance imaging (fMRI) food-picture evaluation task after a 16-h overnight fast (Fasted-Saline) or after eating breakfast 95 min before scanning (730 kcal, 14% protein, 31% fat, and 55% carbohydrate) and receiving a saline (Fed-Saline) or acyl ghrelin (Fed-Ghrelin) subcutaneous injection before scanning. One male subject was excluded from the fMRI analysis because of excess head motion, which left 21 subjects with brain-activation data. Compared with the Fed-Saline visit, both ghrelin administration to fed subjects (Fed-Ghrelin) and fasting (Fasted-Saline) significantly increased the appeal of high-energy foods and associated orbitofrontal cortex activation. Both fasting and ghrelin administration also increased hippocampus activation to high-energy- and low-energy-food pictures. These similar effects of endogenous and exogenous hyperghrelinemia were not explicable by consistent changes in glucose, insulin, peptide YY, and glucagon-like peptide-1. Neither ghrelin administration nor fasting had any significant effect on nucleus accumbens, caudate, anterior insula, or amygdala activation during the food-evaluation task or on auditory, motor, or visual cortex activation during a control task. Ghrelin administration and fasting have similar acute stimulatory effects on hedonic responses and the activation of corticolimbic reward-cognitive systems during food evaluations. Similar effects of recurrent or chronic hyperghrelinemia on an anticipatory food reward may contribute to the negative impact of skipping breakfast on dietary habits and body weight and the long-term failure of energy restriction for weight loss. © 2014 American Society for Nutrition.

  13. Effects of fasting and refeeding on gene expression of slc15a1a, a gene encoding an oligopeptide transporter (PepT1), in the intestine of Mozambique tilapia.

    PubMed

    Orozco, Zenith Gaye A; Soma, Satoshi; Kaneko, Toyoji; Watanabe, Soichi

    2017-01-01

    The tissue distribution of slc15a1a, a gene that encodes an oligopeptide transporter, PepT1, and its response to fasting and refeeding were investigated in the intestinal epithelium of Mozambique tilapia for a better understanding of its role on nutrient absorption. The slc15a1a was predominantly expressed in the absorptive epithelia of the anterior part of the intestine, suggesting that digested oligopeptides are primarily absorbed in the anterior intestine. The response of slc15a1a to fasting was evaluated at 1, 2, 4, 7 and 14days after the last feeding. Fasting revealed a biphasic effect, where short-term fasting significantly upregulated slc15a1a expression and long-term fasting resulted in downregulation. The expression level continued to decrease and fell below the pre-fasted level from day 4 to 14. Proximal (the hepatic loop, HL) and distal parts (the proximal major coil, PMC) of the anterior intestine showed different magnitudes of responses to fasting; slc15a1a expression in the PMC showed greater upregulation and downregulation than that in the HL. Refeeding significantly stimulated slc15a1a expression at day 3, although the expression did not exceed the pre-fasted level. Observed responses of slc15a1a to fasting and refeeding suggest that the expression level of this gene can serve as a sensitive indicator of the changes that may occur in altering nutritional conditions. These findings contribute to a better understanding of the role of PepT1 in nutrition and of the complex mechanisms underlying the absorption of oligopeptides and amino acids in the intestine, and may lead to development of possible means to manipulate the absorption processes for the improvement of growth and other metabolic and physiological conditions in fish. Copyright © 2016. Published by Elsevier Inc.

  14. Metabolic and psychological response to 7-day fasting in obese patients with and without metabolic syndrome.

    PubMed

    Li, Chenying; Ostermann, Thomas; Hardt, Monika; Lüdtke, Rainer; Broecker-Preuss, Martina; Dobos, Gustav; Michalsen, Andreas

    2013-01-01

    Extended modified fasting is a frequently practiced tradition in Europe. It is claimed to improve the cardiometabolic state and physical and psychological well-being by an evolutionary co-developed adaptation response. We aimed to investigate the cardiometabolic and psychological effects of a 7-day fast and differences of these responses between patients with or without metabolic syndrome (MetS). We investigated 30 female subjects (49.0 ± 8.1 years, BMI 30.4 ± 6.7 kg/m(2)) with (n = 12) and without (n = 18) MetS. All subjects participated in a 7-day fast according to Buchinger with a nutritional energy intake of 300 kcal/day and stepwise reintroduction of solid food thereafter. Outcomes were assessed baseline and after fasting and included measures of metabolic and glucoregulatory control, adipokines as well as psychological well-being as assessed by Profile of Mood States (POMS) and Hospital Anxiety and Depression Scale (HADS). Mean weight decreased from 85.4 ± 18.8 kg to 79.7 ± 18.2 kg accompanied by systolic/diastolic blood pressure (BP) reduction of -16.2 mm Hg (95% CI: -9.1; -23.3 mm Hg) and -6.0 mm Hg (95% CI: -1.8; -10.3 mm Hg), each p < 0.001 and p = 0.005. Fasting led to marked decreases of levels of LDL-cholesterol, leptin, and insulin and increases of levels of adiponectin, leptin receptors, and resistin. Fasting-induced mood enhancement was reflected by decreased anxiety, depression, fatigue, and improved vigor. Patients with MetS showed some greater changes in B P, LDL-cholesterol, triglycerides, adiponectin, leptin, and sleep quality. Fasting was well-tolerated. Our results point to marked beneficial responses to 7-day modified fasting and a potential role in the prevention of the MetS. Randomized trials with longer observation periods should test the clinical effectiveness of fasting in metabolic diseases. © 2014 S. Karger GmbH, Freiburg.

  15. HEND Maps of Fast Neutrons

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Observations by NASA's 2001 Mars Odyssey spacecraft show a global view of Mars in high-energy, or fast, neutrons. These maps are based on data acquired by the high-energy neutron detector, one of the instruments in the gamma ray spectrometer suite. Fast neutrons, like epithermal neutrons, are sensitive to the presence of hydrogen. Unlike epithermal neutrons, however, they are not affected by the presence of carbon dioxide, which at the time of these observations covered the north polar area as 'dry ice' frost. The low flux of fast neutrons (blue and purple colors) in the north polar region suggests an abundance of hydrogen in the soil comparable to that determined in the south from the flux of epithermal neutrons. These observations were acquired during the first two months of mapping operations. Contours of topography are superimposed on these maps for geographic reference.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson, and NASA's Johnson Space Center, Houston, operate the science instruments. The gamma-ray spectrometer was provided by the University of Arizona in collaboration with the Russian Aviation and Space Agency, which provided the high-energy neutron detector, and the Los Alamos National Laboratories, New Mexico, which provided the neutron spectrometer. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  16. Electron-bombarded CCD detectors for ultraviolet atmospheric remote sensing

    NASA Technical Reports Server (NTRS)

    Carruthers, G. R.; Opal, C. B.

    1983-01-01

    Electronic image sensors based on charge coupled devices operated in electron-bombarded mode, yielding real-time, remote-readout, photon-limited UV imaging capability are being developed. The sensors also incorporate fast-focal-ratio Schmidt optics and opaque photocathodes, giving nearly the ultimate possible diffuse-source sensitivity. They can be used for direct imagery of atmospheric emission phenomena, and for imaging spectrography with moderate spatial and spectral resolution. The current state of instrument development, laboratory results, planned future developments and proposed applications of the sensors in space flight instrumentation is described.

  17. Fabrication of capsule assemblies, phase 3

    NASA Technical Reports Server (NTRS)

    Keeton, A. R.; Stemann, L. G.

    1973-01-01

    Thirteen capsule assemblies were fabricated for evaluation of fuel pin design concepts for a fast spectrum lithium cooled compact space power reactor. These instrumented assemblies were designed for real time test of prototype fuel pins. Uranium mononitride fuel pins were encased in AISI 304L stainless steel capsules. Fabrication procedures were fully qualified by process development and assembly qualification tests. Instrumentation reliability was achieved utilizing specially processed and closely controlled thermocouple hot zone fabrication and by thermal screening tests. Overall capsule reliability was achieved with an all electron beam welded assembly.

  18. NEUTRON ABSORPTION AND SHIELDING DEVICE

    DOEpatents

    Axelrad, I.R.

    1960-06-21

    A neutron absorption and shielding device is described which is adapted for mounting in a radiation shielding wall surrounding a radioactive area through which instrumentation leads and the like may safely pass without permitting gamma or neutron radiation to pass to the exterior. The shielding device comprises a container having at least one nonrectilinear tube or passageway means extending therethrough, which is adapted to contain instrumentation leads or the like, a layer of a substance capable of absorbing gamma rays, and a solid resinous composition adapted to attenuate fast-moving neutrons and capture slow- moving or thermal neutrons.

  19. Polylactide-based polyurethane shape memory nanocomposites (Fe3O4/PLAUs) with fast magnetic responsiveness

    NASA Astrophysics Data System (ADS)

    Gu, Shu-Ying; Jin, Sheng-Peng; Gao, Xie-Feng; Mu, Jian

    2016-05-01

    Polylactide-based polyurethane shape memory nanocomposites (Fe3O4/PLAUs) with fast magnetic responsiveness are presented. For the purpose of fast response and homogeneous dispersion of magnetic nanoparticles, oleic acid was used to improve the dispersibility of Fe3O4 nanoparticles in a polymer matrix. A homogeneous distribution of Fe3O4 nanoparticles in the polymer matrix was obtained for nanocomposites with low Fe3O4 loading content. A small agglomeration was observed for nanocomposites with 6 wt% and 9 wt% loading content, leading to a small decline in the mechanical properties. PLAU and its nanocomposites have glass transition around 52 °C, which can be used as the triggering temperature. PLAU and its nanocomposites have shape fixity ratios above 99%, shape recovery ratios above 82% for the first cycle and shape recovery ratios above 91% for the second cycle. PLAU and its nanocomposites also exhibit a fast water bath or magnetic responsiveness. The magnetic recovery time decreases with an increase in the loading content of Fe3O4 nanoparticles due to an improvement in heating performance for increased weight percentage of fillers. The nanocomposites have fast responses in an alternating magnetic field and have potential application in biomedical areas such as intravascular stent.

  20. Construction of a High Temporal-spectral Resolution Spectrometer for Detection of Fast Transients from Observations of the Sun at 1.4 GHz.

    NASA Astrophysics Data System (ADS)

    Casillas-Perez, G. A.; Jeyakumar, S.; Perez-Enriquez, R.

    2014-12-01

    Transients explosive events with time durations from nanoseconds to several hours, are observed in the Sun at high energy bands such as gamma ray and xray. In the radio band, several types of radio bursts are commonly detected from the ground. A few observations of the Sun in the past have also detected a new class of fast transients which are known to have short-live electromagnetic emissions with durations less than 100 ms. The mechanisms that produce such fast transiets remain unclear. Observations of such fast transients over a wide bandwidth is necessary to uderstand the underlying physical process that produce such fast transients. Due to their very large flux densities, fast radio transients can be observed at high time resolution using small antennas in combination with digital signal processing techniques. In this work we report the progress of an spectrometer that is currently in construction at the Observatorio de la Luz of the Universidad de Guanajuato. The instrument which will have the purpose of detecting solar fast radio transients, involves the use of digital devices such as FPGA and ADC cards, in addition with a receiver with high temporal-spectral resolution centered at 1.4 GHz and a pair of 2.3 m satellite dish.

  1. Impact of Nuclear Data Uncertainties on Calculated Spent Fuel Nuclide Inventories and Advanced NDA Instrument Response

    DOE PAGES

    Hu, Jianwei; Gauld, Ian C.

    2014-12-01

    The U.S. Department of Energy’s Next Generation Safeguards Initiative Spent Fuel (NGSI-SF) project is nearing the final phase of developing several advanced nondestructive assay (NDA) instruments designed to measure spent nuclear fuel assemblies for the purpose of improving nuclear safeguards. Current efforts are focusing on calibrating several of these instruments with spent fuel assemblies at two international spent fuel facilities. Modelling and simulation is expected to play an important role in predicting nuclide compositions, neutron and gamma source terms, and instrument responses in order to inform the instrument calibration procedures. As part of NGSI-SF project, this work was carried outmore » to assess the impacts of uncertainties in the nuclear data used in the calculations of spent fuel content, radiation emissions and instrument responses. Nuclear data is an essential part of nuclear fuel burnup and decay codes and nuclear transport codes. Such codes are routinely used for analysis of spent fuel and NDA safeguards instruments. Hence, the uncertainties existing in the nuclear data used in these codes affect the accuracies of such analysis. In addition, nuclear data uncertainties represent the limiting (smallest) uncertainties that can be expected from nuclear code predictions, and therefore define the highest attainable accuracy of the NDA instrument. This work studies the impacts of nuclear data uncertainties on calculated spent fuel nuclide inventories and the associated NDA instrument response. Recently developed methods within the SCALE code system are applied in this study. The Californium Interrogation with Prompt Neutron instrument was selected to illustrate the impact of these uncertainties on NDA instrument response.« less

  2. Impact of Nuclear Data Uncertainties on Calculated Spent Fuel Nuclide Inventories and Advanced NDA Instrument Response

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, Jianwei; Gauld, Ian C.

    The U.S. Department of Energy’s Next Generation Safeguards Initiative Spent Fuel (NGSI-SF) project is nearing the final phase of developing several advanced nondestructive assay (NDA) instruments designed to measure spent nuclear fuel assemblies for the purpose of improving nuclear safeguards. Current efforts are focusing on calibrating several of these instruments with spent fuel assemblies at two international spent fuel facilities. Modelling and simulation is expected to play an important role in predicting nuclide compositions, neutron and gamma source terms, and instrument responses in order to inform the instrument calibration procedures. As part of NGSI-SF project, this work was carried outmore » to assess the impacts of uncertainties in the nuclear data used in the calculations of spent fuel content, radiation emissions and instrument responses. Nuclear data is an essential part of nuclear fuel burnup and decay codes and nuclear transport codes. Such codes are routinely used for analysis of spent fuel and NDA safeguards instruments. Hence, the uncertainties existing in the nuclear data used in these codes affect the accuracies of such analysis. In addition, nuclear data uncertainties represent the limiting (smallest) uncertainties that can be expected from nuclear code predictions, and therefore define the highest attainable accuracy of the NDA instrument. This work studies the impacts of nuclear data uncertainties on calculated spent fuel nuclide inventories and the associated NDA instrument response. Recently developed methods within the SCALE code system are applied in this study. The Californium Interrogation with Prompt Neutron instrument was selected to illustrate the impact of these uncertainties on NDA instrument response.« less

  3. Monitoring Instrument Performance in Regional Broadband Seismic Network Using Ambient Seismic Noise

    NASA Astrophysics Data System (ADS)

    Ye, F.; Lyu, S.; Lin, J.

    2017-12-01

    In the past ten years, the number of seismic stations has increased significantly, and regional seismic networks with advanced technology have been gradually developed all over the world. The resulting broadband data help to improve the seismological research. It is important to monitor the performance of broadband instruments in a new network in a long period of time to ensure the accuracy of seismic records. Here, we propose a method that uses ambient noise data in the period range 5-25 s to monitor instrument performance and check data quality in situ. The method is based on an analysis of amplitude and phase index parameters calculated from pairwise cross-correlations of three stations, which provides multiple references for reliable error estimates. Index parameters calculated daily during a two-year observation period are evaluated to identify stations with instrument response errors in near real time. During data processing, initial instrument responses are used in place of available instrument responses to simulate instrument response errors, which are then used to verify our results. We also examine feasibility of the tailing noise using data from stations selected from USArray in different locations and analyze the possible instrumental errors resulting in time-shifts used to verify the method. Additionally, we show an application that effects of instrument response errors that experience pole-zeros variations on monitoring temporal variations in crustal properties appear statistically significant velocity perturbation larger than the standard deviation. The results indicate that monitoring seismic instrument performance helps eliminate data pollution before analysis begins.

  4. Improved Detection System Description and New Method for Accurate Calibration of Micro-Channel Plate Based Instruments and Its Use in the Fast Plasma Investigation on NASA's Magnetospheric MultiScale Mission

    NASA Technical Reports Server (NTRS)

    Gliese, U.; Avanov, L. A.; Barrie, A. C.; Kujawski, J. T.; Mariano, A. J.; Tucker, C. J.; Chornay, D. J.; Cao, N. T.; Gershman, D. J.; Dorelli, J. C.; hide

    2015-01-01

    The Fast Plasma Investigation (FPI) on NASAs Magnetospheric MultiScale (MMS) mission employs 16 Dual Electron Spectrometers (DESs) and 16 Dual Ion Spectrometers (DISs) with 4 of each type on each of 4 spacecraft to enable fast (30 ms for electrons; 150 ms for ions) and spatially differentiated measurements of the full 3D particle velocity distributions. This approach presents a new and challenging aspect to the calibration and operation of these instruments on ground and in flight. The response uniformity, the reliability of their calibration and the approach to handling any temporal evolution of these calibrated characteristics all assume enhanced importance in this application, where we attempt to understand the meaning of particle distributions within the ion and electron diffusion regions of magnetically reconnecting plasmas. Traditionally, the micro-channel plate (MCP) based detection systems for electrostatic particle spectrometers have been calibrated using the plateau curve technique. In this, a fixed detection threshold is set. The detection system count rate is then measured as a function of MCP voltage to determine the MCP voltage that ensures the count rate has reached a constant value independent of further variation in the MCP voltage. This is achieved when most of the MCP pulse height distribution (PHD) is located at higher values (larger pulses) than the detection system discrimination threshold. This method is adequate in single-channel detection systems and in multi-channel detection systems with very low crosstalk between channels. However, in dense multi-channel systems, it can be inadequate. Furthermore, it fails to fully describe the behavior of the detection system and individually characterize each of its fundamental parameters. To improve this situation, we have developed a detailed phenomenological description of the detection system, its behavior and its signal, crosstalk and noise sources. Based on this, we have devised a new detection system calibration method that enables accurate and repeatable measurement and calibration of MCP gain, MCP efficiency, signal loss due to variation in gain and efficiency, crosstalk from effects both above and below the MCP, noise margin, and stability margin in one single measurement. More precise calibration is highly desirable as the instruments will produce higher quality raw data that will require less post-acquisition data correction using results from in-flight pitch angle distribution measurements and ground calibration measurements. The detection system description and the fundamental concepts of this new calibration method, named threshold scan, will be presented. It will be shown how to derive all the individual detection system parameters and how to choose the optimum detection system operating point. This new method has been successfully applied to achieve a highly accurate calibration of the DESs and DISs of the MMS mission. The practical application of the method will be presented together with the achieved calibration results and their significance. Finally, it will be shown that, with further detailed modeling, this method can be extended for use in flight to achieve and maintain a highly accurate detection system calibration across a large number of instruments during the mission.

  5. Aversive pavlovian responses affect human instrumental motor performance.

    PubMed

    Rigoli, Francesco; Pavone, Enea Francesco; Pezzulo, Giovanni

    2012-01-01

    IN NEUROSCIENCE AND PSYCHOLOGY, AN INFLUENTIAL PERSPECTIVE DISTINGUISHES BETWEEN TWO KINDS OF BEHAVIORAL CONTROL: instrumental (habitual and goal-directed) and Pavlovian. Understanding the instrumental-Pavlovian interaction is fundamental for the comprehension of decision-making. Animal studies (as those using the negative auto-maintenance paradigm), have demonstrated that Pavlovian mechanisms can have maladaptive effects on instrumental performance. However, evidence for a similar effect in humans is scarce. In addition, the mechanisms modulating the impact of Pavlovian responses on instrumental performance are largely unknown, both in human and non-human animals. The present paper describes a behavioral experiment investigating the effects of Pavlovian conditioned responses on performance in humans, focusing on the aversive domain. Results showed that Pavlovian responses influenced human performance, and, similar to animal studies, could have maladaptive effects. In particular, Pavlovian responses either impaired or increased performance depending on modulator variables such as threat distance, task controllability, punishment history, amount of training, and explicit punishment expectancy. Overall, these findings help elucidating the computational mechanisms underlying the instrumental-Pavlovian interaction, which might be at the base of apparently irrational phenomena in economics, social behavior, and psychopathology.

  6. Aversive Pavlovian Responses Affect Human Instrumental Motor Performance

    PubMed Central

    Rigoli, Francesco; Pavone, Enea Francesco; Pezzulo, Giovanni

    2012-01-01

    In neuroscience and psychology, an influential perspective distinguishes between two kinds of behavioral control: instrumental (habitual and goal-directed) and Pavlovian. Understanding the instrumental-Pavlovian interaction is fundamental for the comprehension of decision-making. Animal studies (as those using the negative auto-maintenance paradigm), have demonstrated that Pavlovian mechanisms can have maladaptive effects on instrumental performance. However, evidence for a similar effect in humans is scarce. In addition, the mechanisms modulating the impact of Pavlovian responses on instrumental performance are largely unknown, both in human and non-human animals. The present paper describes a behavioral experiment investigating the effects of Pavlovian conditioned responses on performance in humans, focusing on the aversive domain. Results showed that Pavlovian responses influenced human performance, and, similar to animal studies, could have maladaptive effects. In particular, Pavlovian responses either impaired or increased performance depending on modulator variables such as threat distance, task controllability, punishment history, amount of training, and explicit punishment expectancy. Overall, these findings help elucidating the computational mechanisms underlying the instrumental-Pavlovian interaction, which might be at the base of apparently irrational phenomena in economics, social behavior, and psychopathology. PMID:23060738

  7. The cyclotron energization through auroral wave experiments (CENTAUR 2B)

    NASA Technical Reports Server (NTRS)

    Winningham, J. D.

    1992-01-01

    The CENTAUR 2B mission, a dual payload program, is in many aspects the same as the previous missions from Cape Perry and Norway in 1985. It was planned that these payloads would be launched from Andoya, Norway, Nov. 1989 from the Universal II launcher. The payloads are identical, but would have been launched at different azimuths as far north and as far west as possible. Particle experiments include the angular resolving energy analyzer (AREA), the fast ion mass spectrometer (FIMS), the spectrographic particle images (SPI), and finally, the differential ion flux probe (DIFP). SwRI was responsible for the scientific payload, which includes the power supplies, the power supply interfacing, the manipulating of the data from the instruments to format it for the telemetry system, all mechanical structure and restraint mechanisms, and the payload subskin. The status of the various components of this program is given.

  8. Avalanche photodiode based time-of-flight mass spectrometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ogasawara, Keiichi, E-mail: kogasawara@swri.edu; Livi, Stefano A.; Desai, Mihir I.

    2015-08-15

    This study reports on the performance of Avalanche Photodiodes (APDs) as a timing detector for ion Time-of-Flight (TOF) mass spectroscopy. We found that the fast signal carrier speed in a reach-through type APD enables an extremely short timescale response with a mass or energy independent <2 ns rise time for <200 keV ions (1−40 AMU) under proper bias voltage operations. When combined with a microchannel plate to detect start electron signals from an ultra-thin carbon foil, the APD comprises a novel TOF system that successfully operates with a <0.8 ns intrinsic timing resolution even using commercial off-the-shelf constant-fraction discriminators. Bymore » replacing conventional total-energy detectors in the TOF-Energy system, APDs offer significant power and mass savings or an anti-coincidence background rejection capability in future space instrumentation.« less

  9. Pancreatic cancer cell detection by targeted lipid microbubbles and multiphoton imaging.

    PubMed

    Cromey, Benjamin; McDaniel, Ashley; Matsunaga, Terry; Vagner, Josef; Kieu, Khanh Quoc; Banerjee, Bhaskar

    2018-04-01

    Surgical resection of pancreatic cancer represents the only chance of cure and long-term survival in this common disease. Unfortunately, determination of a cancer-free margin at surgery is based on one or two tiny frozen section biopsies, which is far from ideal. Not surprisingly, cancer is usually left behind and is responsible for metastatic disease. We demonstrate a method of receptor-targeted imaging using peptide ligands, lipid microbubbles, and multiphoton microscopy that could lead to a fast and accurate way of examining the entire cut surface during surgery. Using a plectin-targeted microbubble, we performed a blinded in-vitro study to demonstrate avid binding of targeted microbubbles to pancreatic cancer cells but not noncancerous cell lines. Further work should lead to a much-needed point-of-care diagnostic test for determining clean margins in oncologic surgery. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  10. STS-107 Crew Interviews: Rick D. Husband, Commander

    NASA Technical Reports Server (NTRS)

    2002-01-01

    STS-107 Commander Rick Husband is seen during this preflight interview, where he gives a quick overview of the mission before answering questions about his inspiration to become an astronaut and his career path. Husband outlines what his role in the mission will be, what training the crew received, what crew member responsibilities will be, particularly during launch and reentry, what day to day life will be like on an extended duration mission, and what science experiments are going to be conducted onboard. He discusses the following science experiments and instruments in detail: MEIDEX (Mediterranean Israeli Dust Experiment), SOLSE (Shuttle Ozone Limb Sounding Experiment, FREESTAR (Fast Reaction Enabling Science Technology and Research) and various student projects. Husband also touches on the importance of space research, the value of international cooperation, the reason for dual crew shifts on the mission and the role of crew members as research subjects.

  11. STS-107 Crew Interviews: Michael Anderson, Mission Specialist

    NASA Technical Reports Server (NTRS)

    2002-01-01

    STS-107 Mission Specialist 3 and Payload Commander Michael Anderson is seen during this preflight interview, where he gives a quick overview of the mission before answering questions about his inspiration to become an astronaut and his career path. He outlines his role in the mission in general, and specifically in conducting onboard science experiments. He discusses the following instruments and sets of experiments in detail: CM2 (Combustion Module 2), FREESTAR (Fast Reaction Enabling Science Technology and Research, MEIDEX (Mediterranean Israeli Dust Experiment) and MGM (Mechanics of Granular Materials). Anderson also mentions on-board activities and responsibilities during launch and reentry, mission training, and microgravity research. In addition, he touches on the dual work-shift nature of the mission, the use of crew members as research subjects including pre and postflight monitoring activities, the emphasis on crew safety during training and the value of international cooperation.

  12. Determination of nitrobenzene in wastewater using a hanging mercury drop electrode.

    PubMed

    Liang, Shu-Xuan; Zhang, Huan-Kun; Lu, Da

    2007-06-01

    The determination of trace amount nitrobenzene in wastewater on a hanging mercury drop electrode was studied. The determination conditions of pH, supporting electrolyte, accumulation potential, accumulation time, and voltammetric response were optimized. The sharp peak of the nitrobenzene was appeared at 0.05 V. The peak electric current was proportional to the concentration of nitrobenzene in the range of 1.47 x 10(-5) approximately 1.0 x 10(-3) mol/l with relative standard deviations of 3.99 approximately 8.94%. The detection limit of the nitrobenzene in water was 5 x 10(-6) mol/l. The proposed method offered low limit of determination, easy operation, the use of simple instrumentation, high sensitivity and good reproducibility. It was applied to the determination of nitrobenzene in wastewater with an average recovery of 94.0% approximately 105%. The proposed method provided fast, sensitive and sometimes real time detection of nitrobenzene.

  13. Slow Monitoring Systems for CUORE

    NASA Astrophysics Data System (ADS)

    Dutta, Suryabrata; Cuore Collaboration

    2016-09-01

    The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale neutrinoless double-beta decay experiment under construction at the Laboratori Nazionali del Gran Sasso (LNGS). The experiment is comprised of 988 TeO2 bolometric crystals arranged into 19 towers and operated at a temperature of 10 mK. We have developed slow monitoring systems to monitor the cryostat during detector installation, commissioning, data taking, and other crucial phases of the experiment. Our systems use responsive LabVIEW virtual instruments and video streams of the cryostat. We built a website using the Angular, Bootstrap, and MongoDB frameworks to display this data in real-time. The website can also display archival data and send alarms. I will present how we constructed these slow monitoring systems to be robust, accurate, and secure, while maintaining reliable access for the entire collaboration from any platform in order to ensure efficient communications and fast diagnoses of all CUORE systems.

  14. Fast and accurate read-out of interferometric optical fiber sensors

    NASA Astrophysics Data System (ADS)

    Bartholsen, Ingebrigt; Hjelme, Dag R.

    2016-03-01

    We present results from an evaluation of phase and frequency estimation algorithms for read-out instrumentation of interferometric sensors. Tests on interrogating a micro Fabry-Perot sensor made of semi-spherical stimuli-responsive hydrogel immobilized on a single mode fiber end face, shows that an iterative quadrature demodulation technique (IQDT) implemented on a 32-bit microcontroller unit can achieve an absolute length accuracy of ±50 nm and length change accuracy of ±3 nm using an 80 nm SLED source and a grating spectrometer for interrogation. The mean absolute error for the frequency estimator is a factor 3 larger than the theoretical lower bound for a maximum likelihood estimator. The corresponding factor for the phase estimator is 1.3. The computation time for the IQDT algorithm is reduced by a factor 1000 compared to the full QDT for the same accuracy requirement.

  15. Practiced musical style shapes auditory skills.

    PubMed

    Vuust, Peter; Brattico, Elvira; Seppänen, Miia; Näätänen, Risto; Tervaniemi, Mari

    2012-04-01

    Musicians' processing of sounds depends highly on instrument, performance practice, and level of expertise. Here, we measured the mismatch negativity (MMN), a preattentive brain response, to six types of musical feature change in musicians playing three distinct styles of music (classical, jazz, and rock/pop) and in nonmusicians using a novel, fast, and musical sounding multifeature MMN paradigm. We found MMN to all six deviants, showing that MMN paradigms can be adapted to resemble a musical context. Furthermore, we found that jazz musicians had larger MMN amplitude than all other experimental groups across all sound features, indicating greater overall sensitivity to auditory outliers. Furthermore, we observed a tendency toward shorter latency of the MMN to all feature changes in jazz musicians compared to band musicians. These findings indicate that the characteristics of the style of music played by musicians influence their perceptual skills and the brain processing of sound features embedded in music. © 2012 New York Academy of Sciences.

  16. Mailed Fist, Velvet Glove: Soviet Armed Forces as a Political Instrument

    DTIC Science & Technology

    1979-09-30

    the Nineteenth anJ Twentieth Party Congress, 1952-1956. The Hague: Martinus Nijhoff, 1959. Erickson, John. Soviet Military Power. Washington: United...York. Dunellen, 1971. B-19 Kintner, William R. and Harriet Fast Scott, ads. The Nuclear Revolution in Soviet Military Affairs. Norman: University of

  17. Advance Approach to Concept and Design Studies for Space Missions

    NASA Technical Reports Server (NTRS)

    Deutsch, M.; Nichols, J.

    1999-01-01

    Recent automated and advanced techniques developed at JPL have created a streamlined and fast-track approach to initial mission conceptualization and system architecture design, answering the need for rapid turnaround of trade studies for potential proposers, as well as mission and instrument study groups.

  18. Preliminary field trash studies using near-infrared spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Cotton is a cash crop that is important in the world market. Development of instrumental techniques to measure cotton quality parameters which are accurate, precise, and fast would be beneficial. Cotton trash (leaf, etc.) and field trash (plastic bags, etc.) comingled with lint adversely affects th...

  19. Application of the pulsed fast/thermal neutron method for soil elemental analysis

    USDA-ARS?s Scientific Manuscript database

    Soil science is a research field where physic concepts and experimental methods are widely used, particularly in agro-chemistry and soil elemental analysis. Different methods of analysis are currently available. The evolution of nuclear physics (methodology and instrumentation) combined with the ava...

  20. Aerostat-Lofted Instrument Platform and Sampling Method for Determination of Emissions from Open Area Sources

    EPA Science Inventory

    Sampling emissions from open area sources, particularly sources of open burning, is difficult due to fast dilution of emissions and safety concerns for personnel. Representative emission samples can be difficult to obtain with flaming and explosive sources since personnel safety ...

  1. Incretin responses to oral glucose and mixed meal tests and changes in fasting glucose levels during 7 years of follow-up: The Hoorn Meal Study.

    PubMed

    Koopman, A D M; Rutters, F; Rauh, S P; Nijpels, G; Holst, J J; Beulens, J W; Alssema, M; Dekker, J M

    2018-01-01

    We conducted the first prospective observational study in which we examined the association between incretin responses to an oral glucose tolerance test (OGTT) and mixed meal test (MMT) at baseline and changes in fasting glucose levels 7 years later, in individuals who were non-diabetic at baseline. We used data from the Hoorn Meal Study; a population-based cohort study among 121 subjects, aged 61.0±6.7y. GIP and GLP-1 responses were determined at baseline and expressed as total and incremental area under the curve (tAUC and iAUC). The association between incretin response at baseline and changes in fasting glucose levels was assessed using linear regression. The average change in glucose over 7 years was 0.43 ± 0.5 mmol/l. For GIP, no significant associations were observed with changes in fasting glucose levels. In contrast, participants within the middle and highest tertile of GLP-1 iAUC responses to OGTT had significantly smaller increases (actually decreases) in fasting glucose levels; -0.28 (95% confidence interval: -0.54;-0.01) mmol/l and -0.39 (-0.67;-0.10) mmol/l, respectively, compared to those in the lowest tertile. The same trend was observed for tAUC GLP-1 following OGTT (highest tertile: -0.32 (0.61;-0.04) mmol/l as compared to the lowest tertile). No significant associations were observed for GLP-1 responses following MMT. In conclusion, within our non-diabetic population-based cohort, a low GLP-1 response to OGTT was associated with a steeper increase in fasting glucose levels during 7 years of follow-up. This suggests that a reduced GLP-1 response precedes glucose deterioration and may play a role in the etiology of type 2 diabetes mellitus.

  2. Incretin responses to oral glucose and mixed meal tests and changes in fasting glucose levels during 7 years of follow-up: The Hoorn Meal Study

    PubMed Central

    Rutters, F.; Rauh, S. P.; Nijpels, G.; Holst, J. J.; Beulens, J. W.; Alssema, M.; Dekker, J. M.

    2018-01-01

    We conducted the first prospective observational study in which we examined the association between incretin responses to an oral glucose tolerance test (OGTT) and mixed meal test (MMT) at baseline and changes in fasting glucose levels 7 years later, in individuals who were non-diabetic at baseline. We used data from the Hoorn Meal Study; a population-based cohort study among 121 subjects, aged 61.0±6.7y. GIP and GLP-1 responses were determined at baseline and expressed as total and incremental area under the curve (tAUC and iAUC). The association between incretin response at baseline and changes in fasting glucose levels was assessed using linear regression. The average change in glucose over 7 years was 0.43 ± 0.5 mmol/l. For GIP, no significant associations were observed with changes in fasting glucose levels. In contrast, participants within the middle and highest tertile of GLP-1 iAUC responses to OGTT had significantly smaller increases (actually decreases) in fasting glucose levels; -0.28 (95% confidence interval: -0.54;-0.01) mmol/l and -0.39 (-0.67;-0.10) mmol/l, respectively, compared to those in the lowest tertile. The same trend was observed for tAUC GLP-1 following OGTT (highest tertile: -0.32 (0.61;-0.04) mmol/l as compared to the lowest tertile). No significant associations were observed for GLP-1 responses following MMT. In conclusion, within our non-diabetic population-based cohort, a low GLP-1 response to OGTT was associated with a steeper increase in fasting glucose levels during 7 years of follow-up. This suggests that a reduced GLP-1 response precedes glucose deterioration and may play a role in the etiology of type 2 diabetes mellitus. PMID:29324870

  3. Association of fasting triglyceride concentration and postprandial triglyceride response with the carotid intima-media thickness in the middle aged: The Netherlands Epidemiology of Obesity study.

    PubMed

    Christen, Tim; de Mutsert, Renée; Gast, Karin B; Rensen, Patrick C N; de Koning, Eelco; Rosendaal, Frits R; Trompet, Stella; Jukema, J Wouter

    People are in a postprandial state for the majority of the day, postprandial triglyceride (TG) response may be more important in the etiology of atherosclerosis than fasting TGs. The objective of the study was to investigate the associations of fasting TG concentration (TGc) and postprandial TG response after a meal challenge with subclinical atherosclerosis, measured by intima-media thickness (IMT) in a middle-aged population. A total of 5574 participants (57% women) with a mean (standard deviation [SD]) age of 56 (6) years were included in this cross-sectional analysis of baseline measurements of The Netherlands Epidemiology of Obesity study. Serum TGc was measured fasting and 30 and 150 minutes after a liquid mixed meal, and the incremental area under the curve (TGiAUC) was calculated. With linear regression analyses, we calculated the differences in IMT with 95% confidence intervals, adjusted for confounding factors, and additionally for TGc or TGiAUC. Per SD of TGc (0.82 mmol/L), IMT was 8.5 μm (2.1, 14.9) greater after adjustment for TGiAUC and confounding factors. Per SD of TGiAUC (24.0 mmol/L × min), the difference in IMT was -1.7 μm (-8.5, 5.0) after adjustment for fasting TG and confounding factors. The association between TG response after a mixed meal and IMT disappeared after adjusting for TGc. The association between fasting TG concentration and IMT persisted after adjustment for postprandial TG response. These findings imply that it is not useful to perform a meal challenge in cardiovascular risk stratification. Our results support use of fasting TGc instead of postprandial TG responses for cardiovascular risk stratification in clinical practice. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  4. 40 CFR 202.21 - Standard for operation under stationary test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... generates a sound level in excess of 88 dB(A) measured on an open site with fast meter response at 50 feet... site with fast meter response at 50 feet from the longitudinal centerline of the vehicle when its...

  5. 40 CFR 202.21 - Standard for operation under stationary test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... generates a sound level in excess of 88 dB(A) measured on an open site with fast meter response at 50 feet... site with fast meter response at 50 feet from the longitudinal centerline of the vehicle when its...

  6. 40 CFR 202.21 - Standard for operation under stationary test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... generates a sound level in excess of 88 dB(A) measured on an open site with fast meter response at 50 feet... site with fast meter response at 50 feet from the longitudinal centerline of the vehicle when its...

  7. 40 CFR 202.21 - Standard for operation under stationary test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... generates a sound level in excess of 88 dB(A) measured on an open site with fast meter response at 50 feet... site with fast meter response at 50 feet from the longitudinal centerline of the vehicle when its...

  8. Stokes-vector and Mueller-matrix polarimetry [Invited].

    PubMed

    Azzam, R M A

    2016-07-01

    This paper reviews the current status of instruments for measuring the full 4×1 Stokes vector S, which describes the state of polarization (SOP) of totally or partially polarized light, and the 4×4 Mueller matrix M, which determines how the SOP is transformed as light interacts with a material sample or an optical element or system. The principle of operation of each instrument is briefly explained by using the Stokes-Mueller calculus. The development of fast, automated, imaging, and spectroscopic instruments over the last 50 years has greatly expanded the range of applications of optical polarimetry and ellipsometry in almost every branch of science and technology. Current challenges and future directions of this important branch of optics are also discussed.

  9. A Fast Visible-Infrared Imaging Radiometer Suite Simulator for Cloudy Atmopheres

    NASA Technical Reports Server (NTRS)

    Liu, Chao; Yang, Ping; Nasiri, Shaima L.; Platnick, Steven; Meyer, Kerry G.; Wang, Chen Xi; Ding, Shouguo

    2015-01-01

    A fast instrument simulator is developed to simulate the observations made in cloudy atmospheres by the Visible Infrared Imaging Radiometer Suite (VIIRS). The correlated k-distribution (CKD) technique is used to compute the transmissivity of absorbing atmospheric gases. The bulk scattering properties of ice clouds used in this study are based on the ice model used for the MODIS Collection 6 ice cloud products. Two fast radiative transfer models based on pre-computed ice cloud look-up-tables are used for the VIIRS solar and infrared channels. The accuracy and efficiency of the fast simulator are quantify in comparison with a combination of the rigorous line-by-line (LBLRTM) and discrete ordinate radiative transfer (DISORT) models. Relative errors are less than 2 for simulated TOA reflectances for the solar channels and the brightness temperature differences for the infrared channels are less than 0.2 K. The simulator is over three orders of magnitude faster than the benchmark LBLRTM+DISORT model. Furthermore, the cloudy atmosphere reflectances and brightness temperatures from the fast VIIRS simulator compare favorably with those from VIIRS observations.

  10. Hammered Dulcimer

    NASA Astrophysics Data System (ADS)

    Peterson, David

    The hammered dulcimer, a direct ancestor of the clavichord and the pianoforte, is a folk instrument that developed from eleventh-century antecedents such as the psaltery. They are trapezoidal in shape, with a long base of 40-45 in. and height of 15-18 in. Two bridges, treble and bass, each support 11-16 courses of strings, which are struck with light wooden hammers. The treble bridge divides the strings into a musical fifth, which facilitates the fast playing of diatonic melodies. Historically, the instrument was used as a rhythmic back-up for fiddles and other lead instruments, but since being popularized in the 1970s folk revival, it has become a solo or lead instrument in ensembles. The hammered dulcimer shares many acoustic properties with the piano except that the dulcimer is smaller and undamped, and the lighter, harder hammers give a more percussive sound. A hammered dulcimer player can also play double strokes and can alter instrument timbre by changing strike location. Current instruments are lightweight, 13-30 lb, and reasonably stable, but temperature and humidity changes cause tuning problems which are related to the linear scaling that is intrinsic to the trapezoidal design.

  11. Mission Oriented Support and Theory (MOST) for MMS—the Goddard Space Flight Center/University of California Los Angeles Interdisciplinary Science Program

    NASA Astrophysics Data System (ADS)

    Goldstein, Melvyn L.; Ashour-Abdalla, Maha; Viñas, Adolfo F.; Dorelli, John; Wendel, Deirdre; Klimas, Alex; Hwang, Kyoung-Joo; El-Alaoui, Mostafa; Walker, Raymond J.; Pan, Qingjiang; Liang, Haoming

    2016-03-01

    The MOST IDS team was tasked with focusing on two general areas: The first was to participate with the Fast Plasma Investigation (FPI) team in the development of virtual detectors that model the instrument responses of the MMS FPI sensors. The virtual instruments can be "flown through" both simulation data (from magnetohydrodynamic, hybrid, and kinetic simulations) and Cluster and THEMIS spacecraft data. The goal is to determine signatures of magnetic reconnection expected during the MMS mission. Such signatures can serve as triggers for selection of burst mode downloads. The chapter contributed by the FPI team covers that effort in detail and, therefore, most of that work has not been included here. The second area of emphasis, and the one detailed in this chapter, was to build on past and present knowledge of magnetic reconnection and its physical signatures. Below we describe intensive analyses of Cluster and THEMIS data together with theoretical models and simulations that delineate the plasma signatures that surround sites of reconnection, including the effects of turbulence as well as the detailed kinetic signatures that indicate proximity to reconnection sites. In particular, we point out that particles are energized in several regions, not only at the actual site of reconnection.

  12. Mission Oriented Support and Theory (MOST) for MMS -- The Goddard Space Flight Center/University of California Los Angeles Interdisciplinary Science Program

    NASA Technical Reports Server (NTRS)

    Goldstein, Melvyn L.; Ashour-Abdalla, Maha; F. Vinas, Adolfo; Dorelli, John; Wendel, Deirdre; Klimas, Alex; Hwang, Kyoung-Joo; El-Alaoui, Mostafa; Walker, Raymond J.; Pan, Qingjiang; hide

    2015-01-01

    The MOST IDS team was tasked with focusing on two general areas: The first was to participate with the Fast Plasma Investigation (FPI) team in the development of virtual detectors that model the instrument responses of the MMS FPI sensors. The virtual instruments can be 'flown through' both simulation data (from magnetohydrodynamic, hybrid, and kinetic simulations) and Cluster and THEMIS spacecraft data. The goal is to determine signatures of magnetic reconnection expected during the MMS mission. Such signatures can serve as triggers for selection of burst mode downloads. The chapter contributed by the FPI team covers that effort in detail and, therefore, most of that work has not been included here. The second area of emphasis, and the one detailed in this chapter, was to build on past and present knowledge of magnetic reconnection and its physical signatures. Below we describe intensive analyses of Cluster and THEMIS data together with theoretical models and simulations that delineate the plasma signatures that surround sites of reconnection, including the effects of turbulence as well as the detailed kinetic signatures that indicate proximity to reconnection sites. In particular, we point out that particles are energized in several regions, not only at the actual site of reconnection.

  13. Development of diagnostic SPR based biosensor for the detection of pharmaceutical compounds in saliva

    NASA Astrophysics Data System (ADS)

    Sonny, Susanna; Sesay, Adama M.; Virtanen, Vesa

    2010-11-01

    The aim of the study is to develop diagnostic tests for the detection of pharmaceutical compounds in saliva. Oral fluid is increasingly being considered as an ideal sample matrix. It can be collected non-invasively and causes less stress to the person being tested. The detection of pharmaceutical compounds and drugs in saliva can give valuable information on individual bases on dose response, usage, characterization and clinical diagnostics. Surface plasmon resonance (SPR) is a highly sensitive, fast and label free analytical technique for the detection of molecular interactions. The specific binding of measured analyte onto the active gold sensing surface of the SPR device induces a refractive index change that can be monitored. To monitor these pharmaceutical compounds in saliva the immunoassays were developed using a SPR instrument. The instrument is equipped with a 670nm laser diode and has two sensing channels. Monoclonal antibodies against the pharmaceutical compounds were used to specifically recognise and capture the compounds which intern will have an effect of the refractive index monitored. Preliminary results show that the immunoassays for cocaine and MDMA (3,4-methylenedioxymethamphetamine) are very sensitive and have linear ranges of 0.01 pg/ml - 1 ng/ml and 0.1 pg/ml - 100 ng/ml, respectively.

  14. Optical versus tactile geometry measurement: alternatives or counterparts

    NASA Astrophysics Data System (ADS)

    Lehmann, Peter

    2003-05-01

    This contribution deals with measuring strategies and methods for the determination of several geometrical features, covering the surface micro-topography and the form of mechanical objects. The measuring principles used in optical surface metrology include optical focusing profilers, confocal point measuring and areal measuring sensors as well as interferometrical principles such as white light interferometry and speckle techniques. In comparison with stylus instruments optical techniques provide certain advantages such as a fast data acquisition, in-process applicability or contactless measurement. However, the frequency response characteristics of optical and tactile measurement differ significantly. In addition, optical sensors are commonly more influenced by critical geometrical conditions and optical properties of an object. For precise form measurement mechanical instruments dominate till now. One reason for this may be, that commonly the complete 360 degrees geometry of the measuring object has to be analyzed. Another point is that optical principles such as form measuring interferometry fail in cases of complex object geometry or rougher object surfaces. Other methods, e.g. fringe projection or digital holography, till now do not meet the accuracy demands of precision engineered workpieces. Hence, a combination of mechanical concepts and optical sensors represents an interesting potential for current and future measuring tasks, which require high accuracy and maximum flexibility.

  15. The NOAO NEWFIRM Data Handling System

    NASA Astrophysics Data System (ADS)

    Zárate, N.; Fitzpatrick, M.

    2008-08-01

    The NOAO Extremely Wide-Field IR Mosaic (NEWFIRM) is a new 1-2.4 micron IR camera that is now being commissioned for the 4m Mayall telescope at Kitt Peak. The focal plane consists of a 2x2 mosaic of 2048x2048 arrays offerring a field-of-view of 27.6' on a side. The use of dual MONSOON array controllers permits very fast readout, a scripting interface allows for highly efficient observing modes. We describe the Data Handling System (DHS) for the NEWFIRM camera which is designed to meet the performance requirements of the instrument as well as the observing environment in which in operates. It is responsible for receiving the data stream from the detector and instrument software, rectifying the image geometry, presenting a real-time display of the image to the user, final assembly of a science-grade image with complete headers, as well as triggering automated pipeline and archival functions. The DHS uses an event-based messaging system to control multiple processes on a distributed network of machines. The asynchronous nature of this processing means the DHS operates independently from the camera readout and the design of the system is inherently scalable to larger focal planes that use a greater number of array controllers. Current status and future plans for the DHS are also discussed.

  16. Standardization of collection requirements for fasting samples: for the Working Group on Preanalytical Phase (WG-PA) of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM).

    PubMed

    Simundic, A M; Cornes, M; Grankvist, K; Lippi, G; Nybo, M

    2014-05-15

    Standardized protocols for patient preparation for laboratory testing are currently lacking. Moreover, a great heterogeneity exists in the definitions of "fasting" currently being used among healthcare workers and in the literature. Marked metabolic and hormonal changes occur after food ingestion, mainly due to the absorption of fluids, lipids, proteins, carbohydrates and other food constituents. This postprandial response varies markedly in response to numerous factors, such as eating behavior, food composition, fasting duration, time of the day, chronic and acute smoking, coffee and alcohol consumption. It is therefore crucial to minimize the total variability by controlling as many of these modifying factors as possible. Control of the abovementioned effects on postprandial response can only be achieved by standardizing the way patients are prepared for laboratory testing, i.e. by defining the fasting duration, as well as what is and what is not allowed (e.g., coffee, tea, smoking, water) during the period of fasting prior to sample collection. The aim of this article is to describe the range of effects of different approaches to fasting on laboratory tests, and to provide a framework for the harmonization of definitions for fasting requirements for laboratory tests. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Short-term fasting attenuates the response of the HPG axis to kisspeptin challenge in the adult male rhesus monkey (Macaca mulatta).

    PubMed

    Wahab, Fazal; Aziz, Farzana; Irfan, Shahzad; Zaman, Waheed-Uz; Shahab, Muhammad

    2008-11-07

    In primates, changes in nutritional status affect the hypothalamic-pituitary-gonadal (HPG) axis by still poorly understood mechanisms. Recently, hypothalamic kisspeptin-GPR54 signaling has emerged as a significant regulator of this neuroendocrine axis. The present study was designed to examine whether suppression of the reproductive function by acute food-restriction in a non-human primate is mediated by decreased responsiveness of the HPG axis to endogenous kisspeptin drive. Five intact adult male rhesus monkeys habituated to chair-restraint, received intravenous boli of human kisspeptin-10 (KP10, 50 microg), hCG (50 IU), and vehicle (1 ml) in both fed and 48-h fasting conditions. Plasma concentrations of glucose, cortisol and testosterone (T) were measured by using enzymatic and specific RIAs, respectively. The acute 48-h fasting decreased plasma glucose (P<0.01) and T (P<0.005) levels, and increased cortisol levels (P<0.05). KP10 administration caused a robust stimulation of T secretion in both fed and fasted monkeys. However, mean T concentration and T AUC after KP10 administration were significantly (P<0.01-0.005) reduced in fasted monkeys. Likewise, the time of the first significant increase in post-KP10 T levels was also significantly (P<0.01) delayed. T response to hCG stimulation was similar in fed and fasted monkeys. The present results indicate that under fasting conditions the KP10 induced T response is delayed and suppressed. These data support the notion that fasting-induced suppression of the HPG axis in the adult male rhesus monkey may involve, at least in part, a reduction in the sensitivity of the GnRH neuronal network to endogenous kisspeptin stimulation.

  18. Greater impairment of postprandial triacylglycerol than glucose response in metabolic syndrome subjects with fasting hyperglycaemia.

    PubMed

    Jackson, Kim G; Walden, Charlotte M; Murray, Peter; Smith, Adrian M; Minihane, Anne M; Lovegrove, Julie A; Williams, Christine M

    2013-08-01

    Studies have started to question whether a specific component or combinations of metabolic syndrome (MetS) components may be more important in relation to cardiovascular disease risk. Our aim was to examine the impact of the presence of raised fasting glucose as a MetS component on postprandial lipaemia. Men classified with the MetS underwent a sequential test meal investigation, in which blood samples were taken at regular intervals after a test breakfast (t=0 min) and lunch (t=330 min). Lipids, glucose and insulin were measured in the fasting and postprandial samples. MetS subjects with 3 or 4 components were subdivided into those without (n=34) and with (n=23) fasting hyperglycaemia (≥5.6 mmol/l), irrespective of the combination of components. Fasting lipids and insulin were similar in the two groups, with glucose significantly higher in the men with glucose as a MetS component (P<0.001). Following the test meals, there were higher maximum concentration (maxC), area under the curve (AUC) and incremental AUC (P ≤0.016) for the postprandial triacylglycerol (TAG) response in men with fasting hyperglycaemia. Greater glucose AUC (P<0.001) and insulin maxC (P=0.010) were also observed in these individuals after the test meals. Multiple regression analysis revealed fasting glucose to be an important predictor of the postprandial TAG and glucose response. Our data analysis has revealed a greater impairment of postprandial TAG than glucose response in MetS subjects with raised fasting glucose. The worsening of postprandial lipaemic control may contribute to the greater CVD risk reported in individuals with MetS component combinations which include hyperglycaemia. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Each meal matters in the exposome: Biological and community considerations in fast-food-socioeconomic associations.

    PubMed

    Prescott, Susan L; Logan, Alan C

    2017-11-01

    Advances in omics and microbiome technology have transformed the ways in which the biological consequences of life in the 'ecological theatre' can be visualized. Exposome science examines the total accumulated environmental exposures (both detrimental and beneficial) as a means to understand the response of the 'total organism to the total environment' over time. The repetitive stimulation of compensatory physiological responses (immune, cardiovascular, neuroendocrine) in response to stress - including sources of stress highly relevant to socioeconomic disadvantage - may lead to metabolic dysregulation and cellular damage, ultimately influencing behavior and disease. The collective toll of physiological wear and tear, known as allostatic load, is not paid equally throughout developed societies. It is paid in excess by the disadvantaged. In the context of fast-food, human and experimental research demonstrates that the biological response to a single fast-food-style meal - especially as mediated by the microbiome- is a product of the person's total lived experience, including the ability to buffer the fast-food meal-induced promotion of inflammation and oxidative stress. Emerging research indicates that each meal and its nutritional context matters. As we discuss, equal weekly visits to major fast-food outlets by the affluent and deprived do not translate into biological equivalency. Hence, debate concerning reducing fast-food outlets through policy - especially in disadvantaged neighborhoods where they are prevalent - requires a biological context. The fast-food establishment and fast-food meal - as they represent matters of food justice and press upon non-communicable disease risk - are far more than physical structures and collections of carbohydrate, fat, sugar and sodium. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Discordant signaling and autophagy response to fasting in hearts of obese mice: Implications for ischemia tolerance

    PubMed Central

    Kooren, Joel A.; Parker, Sarah J.; Tucker, Kyle C.; Ravindran, Nandini; Ito, Bruce R.; Huang, Chengqun; Venkatraman, Vidya; Van Eyk, Jennifer E.; Gottlieb, Roberta A.; Mentzer, Robert M.

    2016-01-01

    Autophagy is regulated by nutrient and energy status and plays an adaptive role during nutrient deprivation and ischemic stress. Metabolic syndrome (MetS) is a hypernutritive state characterized by obesity, dyslipidemia, elevated fasting blood glucose levels, and insulin resistance. It has also been associated with impaired autophagic flux and larger-sized infarcts. We hypothesized that diet-induced obesity (DIO) affects nutrient sensing, explaining the observed cardiac impaired autophagy. We subjected male friend virus B NIH (FVBN) mice to a high-fat diet, which resulted in increased weight gain, fat deposition, hyperglycemia, insulin resistance, and larger infarcts after myocardial ischemia-reperfusion. Autophagic flux was impaired after 4 wk on a high-fat diet. To interrogate nutrient-sensing pathways, DIO mice were subjected to overnight fasting, and hearts were processed for biochemical and proteomic analysis. Obese mice failed to upregulate LC3-II or to clear p62/SQSTM1 after fasting, although mRNA for LC3B and p62/SQSTM1 were appropriately upregulated in both groups, demonstrating an intact transcriptional response to fasting. Energy- and nutrient-sensing signal transduction pathways [AMPK and mammalian target of rapamycin (mTOR)] also responded appropriately to fasting, although mTOR was more profoundly suppressed in obese mice. Proteomic quantitative analysis of the hearts under fed and fasted conditions revealed broad changes in protein networks involved in oxidative phosphorylation, autophagy, oxidative stress, protein homeostasis, and contractile machinery. In many instances, the fasting response was quite discordant between lean and DIO mice. Network analysis implicated the peroxisome proliferator-activated receptor and mTOR regulatory nodes. Hearts of obese mice exhibited impaired autophagy, altered proteome, and discordant response to nutrient deprivation. PMID:27199111

  1. Discordant signaling and autophagy response to fasting in hearts of obese mice: Implications for ischemia tolerance.

    PubMed

    Andres, Allen M; Kooren, Joel A; Parker, Sarah J; Tucker, Kyle C; Ravindran, Nandini; Ito, Bruce R; Huang, Chengqun; Venkatraman, Vidya; Van Eyk, Jennifer E; Gottlieb, Roberta A; Mentzer, Robert M

    2016-07-01

    Autophagy is regulated by nutrient and energy status and plays an adaptive role during nutrient deprivation and ischemic stress. Metabolic syndrome (MetS) is a hypernutritive state characterized by obesity, dyslipidemia, elevated fasting blood glucose levels, and insulin resistance. It has also been associated with impaired autophagic flux and larger-sized infarcts. We hypothesized that diet-induced obesity (DIO) affects nutrient sensing, explaining the observed cardiac impaired autophagy. We subjected male friend virus B NIH (FVBN) mice to a high-fat diet, which resulted in increased weight gain, fat deposition, hyperglycemia, insulin resistance, and larger infarcts after myocardial ischemia-reperfusion. Autophagic flux was impaired after 4 wk on a high-fat diet. To interrogate nutrient-sensing pathways, DIO mice were subjected to overnight fasting, and hearts were processed for biochemical and proteomic analysis. Obese mice failed to upregulate LC3-II or to clear p62/SQSTM1 after fasting, although mRNA for LC3B and p62/SQSTM1 were appropriately upregulated in both groups, demonstrating an intact transcriptional response to fasting. Energy- and nutrient-sensing signal transduction pathways [AMPK and mammalian target of rapamycin (mTOR)] also responded appropriately to fasting, although mTOR was more profoundly suppressed in obese mice. Proteomic quantitative analysis of the hearts under fed and fasted conditions revealed broad changes in protein networks involved in oxidative phosphorylation, autophagy, oxidative stress, protein homeostasis, and contractile machinery. In many instances, the fasting response was quite discordant between lean and DIO mice. Network analysis implicated the peroxisome proliferator-activated receptor and mTOR regulatory nodes. Hearts of obese mice exhibited impaired autophagy, altered proteome, and discordant response to nutrient deprivation. Copyright © 2016 the American Physiological Society.

  2. Earth observing system instrument pointing control modeling for polar orbiting platforms

    NASA Technical Reports Server (NTRS)

    Briggs, H. C.; Kia, T.; Mccabe, S. A.; Bell, C. E.

    1987-01-01

    An approach to instrument pointing control performance assessment for large multi-instrument platforms is described. First, instrument pointing requirements and reference platform control systems for the Eos Polar Platforms are reviewed. Performance modeling tools including NASTRAN models of two large platforms, a modal selection procedure utilizing a balanced realization method, and reduced order platform models with core and instrument pointing control loops added are then described. Time history simulations of instrument pointing and stability performance in response to commanded slewing of adjacent instruments demonstrates the limits of tolerable slew activity. Simplified models of rigid body responses are also developed for comparison. Instrument pointing control methods required in addition to the core platform control system to meet instrument pointing requirements are considered.

  3. Reproducibility assessment of brain responses to visual food stimuli in adults with overweight and obesity.

    PubMed

    Drew Sayer, R; Tamer, Gregory G; Chen, Ningning; Tregellas, Jason R; Cornier, Marc-Andre; Kareken, David A; Talavage, Thomas M; McCrory, Megan A; Campbell, Wayne W

    2016-10-01

    The brain's reward system influences ingestive behavior and subsequently obesity risk. Functional magnetic resonance imaging (fMRI) is a common method for investigating brain reward function. This study sought to assess the reproducibility of fasting-state brain responses to visual food stimuli using BOLD fMRI. A priori brain regions of interest included bilateral insula, amygdala, orbitofrontal cortex, caudate, and putamen. Fasting-state fMRI and appetite assessments were completed by 28 women (n = 16) and men (n = 12) with overweight or obesity on 2 days. Reproducibility was assessed by comparing mean fasting-state brain responses and measuring test-retest reliability of these responses on the two testing days. Mean fasting-state brain responses on day 2 were reduced compared with day 1 in the left insula and right amygdala, but mean day 1 and day 2 responses were not different in the other regions of interest. With the exception of the left orbitofrontal cortex response (fair reliability), test-retest reliabilities of brain responses were poor or unreliable. fMRI-measured responses to visual food cues in adults with overweight or obesity show relatively good mean-level reproducibility but considerable within-subject variability. Poor test-retest reliability reduces the likelihood of observing true correlations and increases the necessary sample sizes for studies. © 2016 The Obesity Society.

  4. Reproducibility assessment of brain responses to visual food stimuli in adults with overweight and obesity

    PubMed Central

    Sayer, R Drew; Tamer, Gregory G; Chen, Ningning; Tregellas, Jason R; Cornier, Marc-Andre; Kareken, David A; Talavage, Thomas M; McCrory, Megan A; Campbell, Wayne W

    2016-01-01

    Objective The brain’s reward system influences ingestive behavior and subsequently, obesity risk. Functional magnetic resonance imaging (fMRI) is a common method for investigating brain reward function. We sought to assess the reproducibility of fasting-state brain responses to visual food stimuli using BOLD fMRI. Methods A priori brain regions of interest included bilateral insula, amygdala, orbitofrontal cortex, caudate, and putamen. Fasting-state fMRI and appetite assessments were completed by 28 women (n=16) and men (n=12) with overweight or obesity on 2 days. Reproducibility was assessed by comparing mean fasting-state brain responses and measuring test-retest reliability of these responses on the 2 testing days. Results Mean fasting-state brain responses on Day 2 were reduced compared to Day 1 in the left insula and right amygdala, but mean Day 1 and Day 2 responses were not different in the other regions of interest. With the exception of the left orbitofrontal cortex response (fair reliability), test-retest reliabilities of brain responses were poor or unreliable. Conclusion fMRI-measured responses to visual food cues in adults with overweight or obesity show relatively good mean-level reproducibility, but considerable within-subject variability. Poor test-retest reliability reduces the likelihood of observing true correlations and increases the necessary sample sizes for studies. PMID:27542906

  5. High Performance Computing Multicast

    DTIC Science & Technology

    2012-02-01

    responsiveness, first-tier applications often implement replicated in- memory key-value stores , using them to store state or to cache data from services...alternative that replicates data , combines agreement on update ordering with amnesia freedom, and supports both good scalability and fast response. A...alternative that replicates data , combines agreement on update ordering with amnesia freedom, and supports both good scalability and fast response

  6. Dimension Reduction of Hyperspectral Data on Beowulf Clusters

    NASA Technical Reports Server (NTRS)

    El-Ghazawi, Tarek

    2000-01-01

    Traditional remote sensing instruments are multispectral, where observations are collected at a few different spectral bands. Recently, many hyperspectral instruments, that can collect observations at hundreds of bands, have been operation. Furthermore, there have been ongoing research efforts on ultraspectral instruments that can produce observations at thousands of spectral bands. While these remote sensing technology developments hold a great promise for new findings in the area of Earth and space science, they present many challenges. These include the need for faster processing of such increased data volumes, and methods for data reduction. Dimension Reduction is a spectral transformation, which is used widely in remote sensing, is the Principal Components Analysis (PCA). In light of the growing number of spectral channels of modern instruments, the paper reports on the development of a parallel PCA and its implementation on two Beowulf cluster configurations, on with fast Ethernet switch and the other is with a Myrinet interconnection.

  7. Miniaturized time-resolved Raman spectrometer for planetary science based on a fast single photon avalanche diode detector array.

    PubMed

    Blacksberg, Jordana; Alerstam, Erik; Maruyama, Yuki; Cochrane, Corey J; Rossman, George R

    2016-02-01

    We present recent developments in time-resolved Raman spectroscopy instrumentation and measurement techniques for in situ planetary surface exploration, leading to improved performance and identification of minerals and organics. The time-resolved Raman spectrometer uses a 532 nm pulsed microchip laser source synchronized with a single photon avalanche diode array to achieve sub-nanosecond time resolution. This instrument can detect Raman spectral signatures from a wide variety of minerals and organics relevant to planetary science while eliminating pervasive background interference caused by fluorescence. We present an overview of the instrument design and operation and demonstrate high signal-to-noise ratio Raman spectra for several relevant samples of sulfates, clays, and polycyclic aromatic hydrocarbons. Finally, we present an instrument design suitable for operation on a rover or lander and discuss future directions that promise great advancement in capability.

  8. Design of Instrument Control Software for Solar Vector Magnetograph at Udaipur Solar Observatory

    NASA Astrophysics Data System (ADS)

    Gosain, Sanjay; Venkatakrishnan, P.; Venugopalan, K.

    2004-04-01

    A magnetograph is an instrument which makes measurement of solar magnetic field by measuring Zeeman induced polarization in solar spectral lines. In a typical filter based magnetograph there are three main modules namely, polarimeter, narrow-band spectrometer (filter), and imager(CCD camera). For a successful operation of magnetograph it is essential that these modules work in synchronization with each other. Here, we describe the design of instrument control system implemented for the Solar Vector Magnetograph under development at Udaipur Solar Observatory. The control software is written in Visual Basic and exploits the Component Object Model (COM) components for a fast and flexible application development. The user can interact with the instrument modules through a Graphical User Interface (GUI) and can program the sequence of magnetograph operations. The integration of Interactive Data Language (IDL) ActiveX components in the interface provides a powerful tool for online visualization, analysis and processing of images.

  9. Response of six neutron survey meters in mixed fields of fast and thermal neutrons.

    PubMed

    Kim, S I; Kim, B H; Chang, I; Lee, J I; Kim, J L; Pradhan, A S

    2013-10-01

    Calibration neutron fields have been developed at KAERI (Korea Atomic Energy Research Institute) to study the responses of commonly used neutron survey meters in the presence of fast neutrons of energy around 10 MeV. The neutron fields were produced by using neutrons from the (241)Am-Be sources held in a graphite pile and a DT neutron generator. The spectral details and the ambient dose equivalent rates of the calibration fields were established, and the responses of six neutron survey meters were evaluated. Four single-moderator-based survey meters exhibited an under-responses ranging from ∼9 to 55 %. DINEUTRUN, commonly used in fields around nuclear reactors, exhibited an over-response by a factor of three in the thermal neutron field and an under-response of ∼85 % in the mixed fields. REM-500 (tissue-equivalent proportional counter) exhibited a response close to 1.0 in the fast neutron fields and an under-response of ∼50 % in the thermal neutron field.

  10. Fast and Slow Precipitation Responses to Individual Climate Forcers: A PDRMIP Multimodel Study

    NASA Technical Reports Server (NTRS)

    Samset, B. H.; Myhre, G.; Forster, P.M.; Hodnebrog, O.; Andrews, T.; Faluvegi, G.; Flaschner, D.; Kasoar, M.; Kharin, V.; Kirkevag, A.; hide

    2016-01-01

    Precipitation is expected to respond differently to various drivers of anthropogenic climate change. We present the first results from the Precipitation Driver and Response Model Intercomparison Project (PDRMIP), where nine global climate models have perturbed CO2, CH4, black carbon, sulfate, and solar insolation. We divide the resulting changes to global mean and regional precipitation into fast responses that scale with changes in atmospheric absorption and slow responses scaling with surface temperature change. While the overall features are broadly similar between models, we find significant regional intermodel variability, especially over land. Black carbon stands out as a component that may cause significant model diversity in predicted precipitation change. Processes linked to atmospheric absorption are less consistently modeled than those linked to top-of-atmosphere radiative forcing. We identify a number of land regions where the model ensemble consistently predicts that fast precipitation responses to climate perturbations dominate over the slow, temperature-driven responses.

  11. Three Days of Intermittent Fasting: Repeated-Sprint Performance Decreased by Vertical-Stiffness Impairment.

    PubMed

    Cherif, Anissa; Meeusen, Romain; Farooq, Abdulaziz; Ryu, Joong; Fenneni, Mohamed Amine; Nikolovski, Zoran; Elshafie, Sittana; Chamari, Karim; Roelands, Bart

    2017-03-01

    To examine the effects of 3 d of intermittent fasting (3d-IF: abstaining from eating/drinking from dawn to sunset) on physical performance and metabolic responses to repeated sprints (RSs). Twenty-one active males performed an RS test (2 sets: 5 × 5-s maximal sprints with 25 s of recovery between and 3 min of recovery between sets on an instrumented treadmill) in 2 conditions: counterbalanced fed/control session (CS) and fasting session (FS). Biomechanical and biochemical markers were assessed preexercise and postexercise. Significant main effects of IF were observed for sprints: maximal speed (P = .016), mean speed (P = .015), maximal power (P = .035), mean power (P = .049), vertical stiffness (P = .032), and vertical center-of-mass displacement (P = .047). Sprint speed and vertical stiffness decreased during the 1st (P = .003 and P = .005) and 2nd sprints (P = .046 and P = .048) of set 2, respectively. Postexercise insulin decreased in CS (P = .023) but not in FS (P = .230). Free-fatty-acid levels were higher in FS than in CS at preexercise (P < .001) and at postexercise (P = .009). High-density lipoprotein cholesterol (HDL-C) was higher at postexercise in FS (1.32 ± 0.22 mmol/L) than in CS (1.26 ± 0.21 mmol/L, P = .039). The triglyceride (TG) concentration was decreased in FS (P < .05) compared with CS. 3d-IF impaired speed and power through a decrease in vertical stiffness during the initial runs of the 2nd set of RS. The findings of the current study confirmed the benefits of 3d-IF: improved HDL-C and TG profiles while maintaining total cholesterol and low-density lipoprotein cholesterol levels. Moreover, improving muscle power might be a key factor to retain a higher vertical stiffness and to partly counteract the negative effects of intermittent fasting.

  12. Ultrafast High Accuracy PCRTM_SOLAR Model for Cloudy Atmosphere

    NASA Technical Reports Server (NTRS)

    Yang, Qiguang; Liu, Xu; Wu, Wan; Yang, Ping; Wang, Chenxi

    2015-01-01

    An ultrafast high accuracy PCRTM_SOLAR model is developed based on PCA compression and principal component-based radiative transfer model (PCRTM). A fast algorithm for simulation of multi-scattering properties of cloud and/or aerosols is integrated into the fast infrared PCRTM. We completed radiance simulation and training for instruments, such as IASI, AIRS, CrIS, NASTI and SHIS, under diverse conditions. The new model is 5 orders faster than 52-stream DISORT with very high accuracy for cloudy sky radiative transfer simulation. It is suitable for hyperspectral remote data assimilation and cloudy sky retrievals.

  13. Fast, cheap and in control: spectral imaging with handheld devices

    NASA Astrophysics Data System (ADS)

    Gooding, Edward A.; Deutsch, Erik R.; Huehnerhoff, Joseph; Hajian, Arsen R.

    2017-05-01

    Remote sensing has moved out of the laboratory and into the real world. Instruments using reflection or Raman imaging modalities become faster, cheaper and more powerful annually. Enabling technologies include virtual slit spectrometer design, high power multimode diode lasers, fast open-loop scanning systems, low-noise IR-sensitive array detectors and low-cost computers with touchscreen interfaces. High-volume manufacturing assembles these components into inexpensive portable or handheld devices that make possible sophisticated decision-making based on robust data analytics. Examples include threat, hazmat and narcotics detection; remote gas sensing; biophotonic screening; environmental remediation and a host of other applications.

  14. Preliminary On-Orbit Neutron Dose Equivalent and Energy Spectrum Results from the ISS-RAD Fast Neutron Detector (FND)

    NASA Technical Reports Server (NTRS)

    Semones, Edward; Leitgab, Martin

    2016-01-01

    The ISS-RAD instrument was activated on ISS on February 1st, 2016. Integrated in ISS-RAD, the Fast Neutron Detector (FND) performs, for the first time on ISS, routine and precise direct neutron measurements between 0.5 and 8 MeV. Preliminary results for neutron dose equivalent and neutron flux energy distributions from online/on-board algorithms and offline ground analyses will be shown, along with comparisons to simulated data and previously measured neutron spectral data. On-orbit data quality and pre-launch analysis validation results will be discussed as well.

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Colosimo, A. M.; Ji, Jianfeng; Stepanov, P. S.

    In this paper, scintillation properties are often studied by photo-luminescence (PL) and scintillation measurements. In this work, we combine X-ray-induced luminescence (XRIL) spectroscopy [Review of Scientific Instruments 83, 103112 (2012)] with PL and standard scintillation measurements to give insight into the scintillation properties of un-doped ZnO single crystals. XRIL revealed that ZnO luminescence proportionally increases with X-ray power and exhibits excellent linearity - indicating the possibility of developing radiation detectors with good energy resolution. Finally, by coupling ZnO crystals to fast photomultiplier tubes and monitoring the anode signal, rise times as fast as 0.9 ns were measured.

  16. Identifying factors associated with fast food consumption among adolescents in Beijing China using a theory-based approach.

    PubMed

    Ma, R; Castellanos, D C; Bachman, J

    2016-07-01

    China is in the midst of the nutrition transition with increasing rates of obesity and dietary changes. One contributor is the increase in fast food chains within the country. The purpose of this study was to develop a theory-based instrument that explores influencing factors of fast food consumption in adolescents residing in Beijing, China. Cross-sectional study. Value expectancy and theory of planned behaviour were utilised to explore influencing factors of fast food consumption in the target population. There were 201 Chinese adolescents between the ages of 12 and 18. Cronbach's alpha correlation coefficients were used to examine internal reliability of the theory-based questionnaire. Bivariate correlations and a MANOVA were utilised to determine the relationship between theory-based constructs, body mass index (BMI)-for-age and fast food intake frequency as well as to determine differences in theory-based scores among fast food consumption frequency groupings. The theory-based questionnaire showed good reliability. Furthermore, there was a significant difference in the theory-based subcategory scores between fast food frequency groups. A significant positive correlation was observed between times per week fast food was consumed and each theory-based subscale score. Using BMI-for-age of 176 participants, 81% were normal weight and 19% were considered overweight or obese. Results showed consumption of fast food to be on average 1.50 ± 1.33 per week. The relationship between BMI-for-age and times per week fast food was consumed was not significant. As the nutrition transition continues and fast food chains expand, it is important to explore factors effecting fast food consumption in China. Interventions targeting influencing factors can be developed to encourage healthy dietary choice in the midst of this transition. Copyright © 2016. Published by Elsevier Ltd.

  17. The effect of meal frequency in a reduced-energy regimen on the gastrointestinal and appetite hormones in patients with type 2 diabetes: A randomised crossover study

    PubMed Central

    Belinova, Lenka; Kahleova, Hana; Oliyarnyk, Olena; Kazdova, Ludmila; Hill, Martin; Pelikanova, Terezie

    2017-01-01

    Background Appetite and gastrointestinal hormones (GIHs) participate in energy homeostasis, feeding behavior and regulation of body weight. We demonstrated previously the superior effect of a hypocaloric diet regimen with lower meal frequency (B2) on body weight, hepatic fat content, insulin sensitivity and feelings of hunger compared to the same diet divided into six smaller meals a day (A6). Studies with isoenergetic diet regimens indicate that lower meal frequency should also have an effect on fasting and postprandial responses of GIHs. The aim of this secondary analysis was to explore the effect of two hypocaloric diet regimens on fasting levels of appetite and GIHs and on their postprandial responses after a standard meal. It was hypothesized that lower meal frequency in a reduced-energy regimen leading to greater body weight reduction and reduced hunger would be associated with decreased plasma concentrations of GIHs: gastric inhibitory peptide (GIP), glucagon-like peptide-1(GLP-1), peptide YY(PYY), pancreatic polypeptide (PP) and leptin and increased plasma concentration of ghrelin. The postprandial response of satiety hormones (GLP-1, PYY and PP) and postprandial suppression of ghrelin will be improved. Methods In a randomized crossover study, 54 patients suffering from type 2 diabetes (T2D) underwent both regimens. The concentrations of GLP-1, GIP, PP, PYY, amylin, leptin and ghrelin were determined using multiplex immunoanalyses. Results Fasting leptin and GIP decreased in response to both regimens with no difference between the treatments (p = 0.37 and p = 0.83, respectively). Fasting ghrelin decreased in A6 and increased in B2 (with difference between regimens p = 0.023). Fasting PP increased in B2with no significant difference between regimens (p = 0.17). Neither GLP-1 nor PYY did change in either regimen. The decrease in body weight correlated negatively with changes in fasting ghrelin (r = -0.4, p<0.043) and the postprandial reduction of ghrelin correlated positively with its fasting level (r = 0.9, p<0.001). The postprandial responses of GIHs and appetite hormones were similar after both diet regimens. Conclusions Both hypocaloric diet regimens reduced fasting leptin and GIP and postprandial response of GIP comparably. The postprandial responses of GIHs and appetite hormones were similar after both diet regimens. Eating only breakfast and lunch increased fasting plasma ghrelin more than the same caloric restriction split into six meals. The changes in fasting ghrelin correlated negatively with the decrease in body weight. These results suggest that for type 2 diabetic patients on a hypocaloric diet, eating larger breakfast and lunch may be more efficient than six smaller meals during the day. PMID:28369078

  18. Portion sizes and obesity: responses of fast-food companies.

    PubMed

    Young, Lisa R; Nestle, Marion

    2007-07-01

    Because the sizes of food portions, especially of fast food, have increased in parallel with rising rates of overweight, health authorities have called on fast-food chains to decrease the sizes of menu items. From 2002 to 2006, we examined responses of fast-food chains to such calls by determining the current sizes of sodas, French fries, and hamburgers at three leading chains and comparing them to sizes observed in 1998 and 2002. Although McDonald's recently phased out its largest offerings, current items are similar to 1998 sizes and greatly exceed those offered when the company opened in 1955. Burger King and Wendy's have increased portion sizes, even while health authorities are calling for portion size reductions. Fast-food portions in the United States are larger than in Europe. These observations suggest that voluntary efforts by fast-food companies to reduce portion sizes are unlikely to be effective, and that policy approaches are needed to reduce energy intake from fast food.

  19. Fully-reversible optical sensor for hydrogen peroxide with fast response.

    PubMed

    Ding, Longjiang; Chen, Siyu; Zhang, Wei; Zhang, Yinglu; Wang, Xu-Dong

    2018-05-09

    A fully reversible optical sensor for hydrogen peroxide with fast response is presented. The sensor was fabricated by in-situ growing ultra-small platinum nanoparticles (PtNPs) inside the pores of fibrous silica particles (KCC-1). The nanocomposite was then embedded into a hydrogel matrix and form a sensor layer, the immobilized PtNPs can catalytically convert hydrogen peroxide into molecular oxygen, which is measured via luminescent quenching based oxygen sensor underneath. Owing to the high porosity and permeability of KCC-1 and high local concentration of PtNPs, the sensor exhibits fast response (less than 1 min) and full reversibility. The measurement range of the sensor covers 1.0 μM to 10.0 mM, and very small amount of sample is required during measurement (200 μL). Because of its high stability, excellent reversibility and selectivity, and extremely fast response, the sensor could fulfill all industry requirements for real-time measurement, and fill market vacancy.

  20. Fast by Nature - How Stress Patterns Define Human Experience and Performance in Dexterous Tasks

    PubMed Central

    Pavlidis, I.; Tsiamyrtzis, P.; Shastri, D.; Wesley, A.; Zhou, Y.; Lindner, P.; Buddharaju, P.; Joseph, R.; Mandapati, A.; Dunkin, B.; Bass, B.

    2012-01-01

    In the present study we quantify stress by measuring transient perspiratory responses on the perinasal area through thermal imaging. These responses prove to be sympathetically driven and hence, a likely indicator of stress processes in the brain. Armed with the unobtrusive measurement methodology we developed, we were able to monitor stress responses in the context of surgical training, the quintessence of human dexterity. We show that in dexterous tasking under critical conditions, novices attempt to perform a task's step equally fast with experienced individuals. We further show that while fast behavior in experienced individuals is afforded by skill, fast behavior in novices is likely instigated by high stress levels, at the expense of accuracy. Humans avoid adjusting speed to skill and rather grow their skill to a predetermined speed level, likely defined by neurophysiological latency. PMID:22396852

  1. Psychometric Comparison of the Functional Assessment Instruments QABF, FACT and FAST for Self-Injurious, Stereotypic and Aggressive/Destructive Behaviour

    ERIC Educational Resources Information Center

    Zaja, Rebecca H.; Moore, Linda; van Ingen, Daniel J.; Rojahn, Johannes

    2011-01-01

    Background: Psychometric properties of three functional assessment rating scales were compared for three types of target behaviours [self-injurious behaviour (SIB), stereotypic behaviour and aggressive/destructive behaviour]. Materials and method: The "Questions about Behavioural Function" (QABF), the "Functional Assessment for…

  2. Using an FPLC to Promote Active Learning of the Principles of Protein Structure and Purification

    ERIC Educational Resources Information Center

    Robinson, Rebekah L.; Neely, Amy E.; Mojadedi, Wais; Threatt, Katie N.; Davis, Nicole Y.; Weiland, Mitch H.

    2017-01-01

    The concepts of protein purification are often taught in undergraduate biology and biochemistry lectures and reinforced during laboratory exercises; however, very few reported activities allow students to directly gain experience using modern protein purification instruments, such as Fast Protein Liquid Chromatography (FPLC). This laboratory…

  3. Fast-scan EM with digital image processing for dynamic experiments

    Treesearch

    C.W. McMillin; F.C. Billingsley; R.E. Frazer

    1974-01-01

    The recent introduction of accessory instrumentation capable of display at television scan rates suggests a broadened application for the scanning electron microscope- the direct observation of motion (dynamic events) at magnifications otherwise unattainable. In one illustrative experiment, the transverse surface of southern pine was observed when subjected to large...

  4. Fast-scan em with digital image processing for dynamic experiments

    Treesearch

    Charles W. McMillin; Fred C. Billingsley; Robert E. Frazer

    1973-01-01

    The recent introduction of accessory instrumentation capable of display at television scan rates suggests a broadened application for the scanning electron microscope - the direct observation of motion (dynamic events) at magnifactions otherwise unattainable. In one illustrative experiment, the transverse surface of southern pine was observed when subjected to large...

  5. Chemical imaging of secondary cell wall development in cotton fibers using a mid-infrared focal-plane array detector

    USDA-ARS?s Scientific Manuscript database

    Market demands for cotton varieties with improved fiber properties also call for the development of fast, reliable analytical methods for monitoring fiber development and measuring their properties. Currently, cotton breeders rely on instrumentation that can require significant amounts of sample, w...

  6. USE OF FAST GC/TOFMS AS REFERENCE STANDARD FOR FIELD COMPARISON STUDIES WITH ON-SITE INSTRUMENTS

    EPA Science Inventory

    A faster reference standard for field comparison studies of portable gas chromatographs (PGC) is needed. A performance evaluation of a high-speed GCMS (FGC/MS) system conducted during 1998 demonstrated generally satisfactory performance, but it was evident that performance of b...

  7. Food cues do not modulate the neuroendocrine response to a prolonged fast in healthy men.

    PubMed

    Snel, Marieke; Wijngaarden, Marjolein A; Bizino, Maurice B; van der Grond, Jeroen; Teeuwisse, Wouter M; van Buchem, Mark A; Jazet, Ingrid M; Pijl, Hanno

    2012-01-01

    Dietary restriction benefits health and increases lifespan in several species. Food odorants restrain the beneficial effects of dietary restriction in Drosophila melanogaster. We hypothesized that the presence of visual and odorous food stimuli during a prolonged fast modifies the neuroendocrine and metabolic response to fasting in humans. In this randomized, crossover intervention study, healthy young men (n = 12) fasted twice for 60 h; once in the presence and once in the absence of food-related visual and odorous stimuli. At baseline and on the last morning of each intervention, an oral glucose tolerance test (OGTT) was performed. During the OGTT, blood was sampled and a functional MRI scan was made. The main effects of prolonged fasting were: (1) decreased plasma thyroid stimulating hormone and triiodothyronine levels; (2) downregulation of the pituitary-gonadal axis; (3) reduced plasma glucose and insulin concentrations, but increased glucose and insulin responses to glucose ingestion; (4) altered hypothalamic blood oxygenation level-dependent (BOLD) signal in response to the glucose load (particularly during the first 20 min after ingestion); (5) increased resting energy expenditure. Exposure to food cues did not affect these parameters. This study shows that 60 h of fasting in young men (1) decreases the hypothalamic BOLD signal in response to glucose ingestion; (2) induces glucose intolerance; (3) increases resting energy expenditure, and (4) downregulates the pituitary-thyroid and pituitary-gonadal axes. Exposure to visual and odorous food cues did not alter these metabolic and neuroendocrine adaptations to nutrient deprivation. Copyright © 2012 S. Karger AG, Basel.

  8. Reinforcement and substitution in humans: a multiple-response analysis1

    PubMed Central

    Bernstein, Daniel J.; Ebbesen, Ebbe B.

    1978-01-01

    Three adult human subjects engaged in activities such as reading, sewing, artwork, and candlemaking while living alone in a laboratory apartment 24 hours per day for several weeks. After a baseline period in which the activities were fully available, access to a particular activity (contingent response) was made dependent on engaging in another less-preferred activity (instrumental response). The contingencies produced substantial increases in instrumental responding, and responding decreased toward baseline levels when the dependency was removed. Under the contingent conditions, time earned for the concurrent activity was always less than the baseline level. To determine the contribution of this reduction to the instrumental increase, access to the contingent activity was restricted in the absence of any dependency. The results indicated that increases among responses that filled the newly available time could be selective, e.g., artwork increased when reading was restricted but candlemaking did not. It was concluded that the reductions in the contingent response that accompany contingencies usually do not exclusively determine instrumental increases, but selective increases can contribute to the increase in time devoted to the instrumental response. PMID:16812105

  9. Cortistatin Is a Key Factor Regulating the Sex-Dependent Response of the GH and Stress Axes to Fasting in Mice.

    PubMed

    Cordoba-Chacón, José; Gahete, Manuel D; Pozo-Salas, Ana I; de Lecea, Luis; Castaño, Justo P; Luque, Raúl M

    2016-07-01

    Cortistatin (CORT) shares high structural and functional similarities with somatostatin (SST) but displays unique sex-dependent pituitary actions. Indeed, although female CORT-knockout (CORT-KO) mice exhibit enhanced GH expression/secretion, Proopiomelanocortin expression, and circulating ACTH/corticosterone/ghrelin levels, male CORT-KO mice only display increased plasma GH/corticosterone levels. Changes in peripheral ghrelin and SST (rather than hypothalamic levels) seem to regulate GH/ACTH axes in CORT-KOs under fed conditions. Because changes in GH/ACTH axes during fasting provide important adaptive mechanisms, we sought to determine whether CORT absence influences GH/ACTH axes during fasting. Accordingly, fed and fasted male/female CORT-KO were compared with littermate controls. Fasting increased circulating GH levels in male/female controls but not in CORT-KO, suggesting that CORT can be a relevant regulator of GH secretion during fasting. However, GH levels were already higher in CORT-KO than in controls in fed state, which might preclude a further elevation in GH levels. Interestingly, although fasting-induced pituitary GH expression was elevated in both male/female controls, GH expression only increased in fasted female CORT-KOs, likely owing to specific changes observed in key factors controlling somatotrope responsiveness (ie, circulating ghrelin and IGF-1, and pituitary GHRH and ghrelin receptor expression). Fasting increased corticosterone levels in control and, most prominently, in CORT-KO mice, which might be associated with a desensitization to SST signaling and to an augmentation in CRH and ghrelin-signaling regulating corticotrope function. Altogether, these results provide compelling evidence that CORT plays a key, sex-dependent role in the regulation of the GH/ACTH axes in response to fasting.

  10. Fasting induces a biphasic adaptive metabolic response in murine small intestine

    PubMed Central

    Sokolović, Milka; Wehkamp, Diederik; Sokolović, Aleksandar; Vermeulen, Jacqueline; Gilhuijs-Pederson, Lisa A; van Haaften, Rachel IM; Nikolsky, Yuri; Evelo, Chris TA; van Kampen, Antoine HC; Hakvoort, Theodorus BM; Lamers, Wouter H

    2007-01-01

    Background The gut is a major energy consumer, but a comprehensive overview of the adaptive response to fasting is lacking. Gene-expression profiling, pathway analysis, and immunohistochemistry were therefore carried out on mouse small intestine after 0, 12, 24, and 72 hours of fasting. Results Intestinal weight declined to 50% of control, but this loss of tissue mass was distributed proportionally among the gut's structural components, so that the microarrays' tissue base remained unaffected. Unsupervised hierarchical clustering of the microarrays revealed that the successive time points separated into distinct branches. Pathway analysis depicted a pronounced, but transient early response that peaked at 12 hours, and a late response that became progressively more pronounced with continued fasting. Early changes in gene expression were compatible with a cellular deficiency in glutamine, and metabolic adaptations directed at glutamine conservation, inhibition of pyruvate oxidation, stimulation of glutamate catabolism via aspartate and phosphoenolpyruvate to lactate, and enhanced fatty-acid oxidation and ketone-body synthesis. In addition, the expression of key genes involved in cell cycling and apoptosis was suppressed. At 24 hours of fasting, many of the early adaptive changes abated. Major changes upon continued fasting implied the production of glucose rather than lactate from carbohydrate backbones, a downregulation of fatty-acid oxidation and a very strong downregulation of the electron-transport chain. Cell cycling and apoptosis remained suppressed. Conclusion The changes in gene expression indicate that the small intestine rapidly looses mass during fasting to generate lactate or glucose and ketone bodies. Meanwhile, intestinal architecture is maintained by downregulation of cell turnover. PMID:17925015

  11. Comparison of a carbohydrate-free diet vs. fasting on plasma glucose, insulin and glucagon in type 2 diabetes.

    PubMed

    Nuttall, Frank Q; Almokayyad, Rami M; Gannon, Mary C

    2015-02-01

    Hyperglycemia improves when patients with type 2 diabetes are placed on a weight-loss diet. Improvement typically occurs soon after diet implementation. This rapid response could result from low fuel supply (calories), lower carbohydrate content of the weight-loss diet, and/or weight loss per se. To differentiate these effects, glucose, insulin, C-peptide and glucagon were determined during the last 24 h of a 3-day period without food (severe calorie restriction) and a calorie-sufficient, carbohydrate-free diet. Seven subjects with untreated type 2 diabetes were studied. A randomized-crossover design with a 4-week washout period between arms was used. Results from both the calorie-sufficient, carbohydrate-free diet and the 3-day fast were compared with the initial standard diet consisting of 55% carbohydrate, 15% protein and 30% fat. The overnight fasting glucose concentration decreased from 196 (standard diet) to 160 (carbohydrate-free diet) to 127 mg/dl (fasting). The 24 h glucose and insulin area responses decreased by 35% and 48% on day 3 of the carbohydrate-free diet, and by 49% and 69% after fasting. Overnight basal insulin and glucagon remained unchanged. Short-term fasting dramatically lowered overnight fasting and 24 h integrated glucose concentrations. Carbohydrate restriction per se could account for 71% of the reduction. Insulin could not entirely explain the glucose responses. In the absence of carbohydrate, the net insulin response was 28% of the standard diet. Glucagon did not contribute to the metabolic adaptations observed. Published by Elsevier Inc.

  12. Transcription factor assisted loading and enhancer dynamics dictate the hepatic fasting response

    PubMed Central

    Goldstein, Ido; Baek, Songjoon; Presman, Diego M.; Paakinaho, Ville; Swinstead, Erin E.; Hager, Gordon L.

    2017-01-01

    Fasting elicits transcriptional programs in hepatocytes leading to glucose and ketone production. This transcriptional program is regulated by many transcription factors (TFs). To understand how this complex network regulates the metabolic response to fasting, we aimed at isolating the enhancers and TFs dictating it. Measuring chromatin accessibility revealed that fasting massively reorganizes liver chromatin, exposing numerous fasting-induced enhancers. By utilizing computational methods in combination with dissecting enhancer features and TF cistromes, we implicated four key TFs regulating the fasting response: glucocorticoid receptor (GR), cAMP responsive element binding protein 1 (CREB1), peroxisome proliferator activated receptor alpha (PPARA), and CCAAT/enhancer binding protein beta (CEBPB). These TFs regulate fuel production by two distinctly operating modules, each controlling a separate metabolic pathway. The gluconeogenic module operates through assisted loading, whereby GR doubles the number of sites occupied by CREB1 as well as enhances CREB1 binding intensity and increases accessibility of CREB1 binding sites. Importantly, this GR-assisted CREB1 binding was enhancer-selective and did not affect all CREB1-bound enhancers. Single-molecule tracking revealed that GR increases the number and DNA residence time of a portion of chromatin-bound CREB1 molecules. These events collectively result in rapid synergistic gene expression and higher hepatic glucose production. Conversely, the ketogenic module operates via a GR-induced TF cascade, whereby PPARA levels are increased following GR activation, facilitating gradual enhancer maturation next to PPARA target genes and delayed ketogenic gene expression. Our findings reveal a complex network of enhancers and TFs that dynamically cooperate to restore homeostasis upon fasting. PMID:28031249

  13. Fasting induces a biphasic adaptive metabolic response in murine small intestine.

    PubMed

    Sokolović, Milka; Wehkamp, Diederik; Sokolović, Aleksandar; Vermeulen, Jacqueline; Gilhuijs-Pederson, Lisa A; van Haaften, Rachel I M; Nikolsky, Yuri; Evelo, Chris T A; van Kampen, Antoine H C; Hakvoort, Theodorus B M; Lamers, Wouter H

    2007-10-09

    The gut is a major energy consumer, but a comprehensive overview of the adaptive response to fasting is lacking. Gene-expression profiling, pathway analysis, and immunohistochemistry were therefore carried out on mouse small intestine after 0, 12, 24, and 72 hours of fasting. Intestinal weight declined to 50% of control, but this loss of tissue mass was distributed proportionally among the gut's structural components, so that the microarrays' tissue base remained unaffected. Unsupervised hierarchical clustering of the microarrays revealed that the successive time points separated into distinct branches. Pathway analysis depicted a pronounced, but transient early response that peaked at 12 hours, and a late response that became progressively more pronounced with continued fasting. Early changes in gene expression were compatible with a cellular deficiency in glutamine, and metabolic adaptations directed at glutamine conservation, inhibition of pyruvate oxidation, stimulation of glutamate catabolism via aspartate and phosphoenolpyruvate to lactate, and enhanced fatty-acid oxidation and ketone-body synthesis. In addition, the expression of key genes involved in cell cycling and apoptosis was suppressed. At 24 hours of fasting, many of the early adaptive changes abated. Major changes upon continued fasting implied the production of glucose rather than lactate from carbohydrate backbones, a downregulation of fatty-acid oxidation and a very strong downregulation of the electron-transport chain. Cell cycling and apoptosis remained suppressed. The changes in gene expression indicate that the small intestine rapidly looses mass during fasting to generate lactate or glucose and ketone bodies. Meanwhile, intestinal architecture is maintained by downregulation of cell turnover.

  14. Micro-machined thermo-conductivity detector

    DOEpatents

    Yu, Conrad

    2003-01-01

    A micro-machined thermal conductivity detector for a portable gas chromatograph. The detector is highly sensitive and has fast response time to enable detection of the small size gas samples in a portable gas chromatograph which are in the order of nanoliters. The high sensitivity and fast response time are achieved through micro-machined devices composed of a nickel wire, for example, on a silicon nitride window formed in a silicon member and about a millimeter square in size. In addition to operating as a thermal conductivity detector, the silicon nitride window with a micro-machined wire therein of the device can be utilized for a fast response heater for PCR applications.

  15. Sources of the solar wind - the heliospheric point of view

    NASA Astrophysics Data System (ADS)

    Von Steiger, Rudolf; Shearer, Paul; Zurbuchen, Thomas

    The solar wind as observed in the heliosphere has several properties that can be interpreted as signatures of conditions and processes at its source in the solar atmosphere. Traditionally it has been customary to distinguish between solar wind types solely based on its speed, "fast" and "slow" wind. Over the last couple of decades new instruments resolving not only the main constituents (protons and alpha particles) but also heavy ions from C to Fe have added new observables, in particular the charge state and elemental composition of these ions. The charge states are indicators of the coronal temperature at the source region; they have confirmed that the "fast" wind emanates from the relatively cool coronal hole regions, while the "slow" wind originates from hotter sources such as the streamer belt and active regions. Thus they are more reliable indicators of solar wind source than the speed alone could be because they readily discriminate between "fast" wind from coronal holes and fast coronal mass ejections (CMEs). The elemental composition in the solar wind compared to the abundances in the photosphere shows a typical fractionation that depends on the first ionization potential (FIP) of the elements. Since that fractionation occurs beneath the corona, in the chromosphere, its strength is indicative of the conditions in that layer. While the "fast" wind is very similar to photospheric composition, the fractionation of the "slow" wind and of CMEs is higher and strongly variable. We will review the observations of the SWICS composition instruments on both the ACE and the Ulysses missions, which have made composition observations between 1 and 5 AU and at all latitudes in the heliosphere over the last two decades. Specifically, analysis of the "slow" wind observations at all time scales, from hours to complete solar cycles, will be used to better characterize its source regions.

  16. Novel Fast Adapting Interneurons Mediate Cholinergic-Induced Fast GABAA IPSCs In Striatal Spiny Neurons

    PubMed Central

    Faust, Thomas W.; Assous, Maxime; Shah, Fulva; Tepper, James M.; Koós, Tibor

    2015-01-01

    Previous work suggests that neostriatal cholinergic interneurons control the activity of several classes of GABAergic interneurons through fast nicotinic receptor mediated synaptic inputs. Although indirect evidence has suggested the existence of several classes of interneurons controlled by this mechanism only one such cell type, the neuropeptide-Y expressing neurogliaform neuron, has been identified to date. Here we tested the hypothesis that in addition to the neurogliaform neurons that elicit slow GABAergic inhibitory responses, another interneuron type exists in the striatum that receives strong nicotinic cholinergic input and elicits conventional fast GABAergic synaptic responses in projection neurons. We obtained in vitro slice recordings from double transgenic mice in which Channelrhodopsin-2 was natively expressed in cholinergic neurons and a population of serotonin receptor-3a-Cre expressing GABAergic interneurons were visualized with tdTomato. We show that among the targeted GABAergic interneurons a novel type of interneuron, termed the fast-adapting interneuron, can be identified that is distinct from previously known interneurons based on immunocytochemical and electrophysiological criteria. We show using optogenetic activation of cholinergic inputs that fast-adapting interneurons receive a powerful supra-threshold nicotinic cholinergic input in vitro. Moreover, fast adapting neurons are densely connected to projection neurons and elicit fast, GABAA receptor mediated inhibitory postsynaptic responses. The nicotinic receptor mediated activation of fast-adapting interneurons may constitute an important mechanism through which cholinergic interneurons control the activity of projection neurons and perhaps the plasticity of their synaptic inputs when animals encounter reinforcing or otherwise salient stimuli. PMID:25865337

  17. GPS Radiation Measurements: Instrument Modeling and Simulation (Project w14_gpsradiation)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sullivan, John P.

    The following topics are covered: electron response simulations and typical calculated response. Monte Carlo calculations of the response of future charged particle instruments (dosimeters) intended to measure the flux of charged particles in space were performed. The electron channels are called E1- E11 – each of which is intended to detect a different range of electron energies. These instruments are on current and future GPS satellites.

  18. The pre-launch characterization of SIMBIO-SYS/VIHI imaging spectrometer for the BepiColombo mission to Mercury. I. Linearity, radiometry, and geometry calibrations.

    PubMed

    Filacchione, Gianrico; Capaccioni, Fabrizio; Altieri, Francesca; Carli, Cristian; Ficai Veltroni, Iacopo; Dami, Michele; Tommasi, Leonardo; Aroldi, Gianluca; Borrelli, Donato; Barbis, Alessandra; Baroni, Marco; Pastorini, Guia; Mugnuolo, Raffaele

    2017-09-01

    Before integration aboard European Space Agency BepiColombo mission to Mercury, the visible and near infrared hyperspectral imager underwent an intensive calibration campaign. We report in Paper I about the radiometric and linearity responses of the instrument including the optical setups used to perform them. Paper II [F. Altieri et al., Rev. Sci. Instrum. 88, 094503 (2017)] will describe complementary spectral response calibration. The responsivity is used to calculate the expected instrumental signal-to-noise ratio for typical observation scenarios of the BepiColombo mission around Mercury. A description is provided of the internal calibration unit that will be used to verify the relative response during the instrument's lifetime. The instrumental spatial response functions as measured along and across the spectrometer's slit direction were determined by means of spatial scans performed with illuminated test slits placed at the focus of a collimator. The dedicated optical setup used for these measurements is described together with the methods used to derive the instrumental spatial responses at different positions within the 3.5 ° field of view and at different wavelengths in the 0.4-2.0 μm spectral range. Finally, instrument imaging capabilities and Modulated Transfer Function are tested by using a standard mask as a target.

  19. Fast parallel tandem mass spectral library searching using GPU hardware acceleration

    PubMed Central

    Baumgardner, Lydia Ashleigh; Shanmugam, Avinash Kumar; Lam, Henry; Eng, Jimmy K.; Martin, Daniel B.

    2011-01-01

    Mass spectrometry-based proteomics is a maturing discipline of biologic research that is experiencing substantial growth. Instrumentation has steadily improved over time with the advent of faster and more sensitive instruments collecting ever larger data files. Consequently, the computational process of matching a peptide fragmentation pattern to its sequence, traditionally accomplished by sequence database searching and more recently also by spectral library searching, has become a bottleneck in many mass spectrometry experiments. In both of these methods, the main rate limiting step is the comparison of an acquired spectrum with all potential matches from a spectral library or sequence database. This is a highly parallelizable process because the core computational element can be represented as a simple but arithmetically intense multiplication of two vectors. In this paper we present a proof of concept project taking advantage of the massively parallel computing available on graphics processing units (GPUs) to distribute and accelerate the process of spectral assignment using spectral library searching. This program, which we have named FastPaSS (for Fast Parallelized Spectral Searching) is implemented in CUDA (Compute Unified Device Architecture) from NVIDIA which allows direct access to the processors in an NVIDIA GPU. Our efforts demonstrate the feasibility of GPU computing for spectral assignment, through implementation of the validated spectral searching algorithm SpectraST in the CUDA environment. PMID:21545112

  20. An ultrahigh-accuracy Miniature Dew Point Sensor based on an Integrated Photonics Platform

    PubMed Central

    Tao, Jifang; Luo, Yu; Wang, Li; Cai, Hong; Sun, Tao; Song, Junfeng; Liu, Hui; Gu, Yuandong

    2016-01-01

    The dew point is the temperature at which vapour begins to condense out of the gaseous phase. The deterministic relationship between the dew point and humidity is the basis for the industry-standard “chilled-mirror” dew point hygrometers used for highly accurate humidity measurements, which are essential for a broad range of industrial and metrological applications. However, these instruments have several limitations, such as high cost, large size and slow response. In this report, we demonstrate a compact, integrated photonic dew point sensor (DPS) that features high accuracy, a small footprint, and fast response. The fundamental component of this DPS is a partially exposed photonic micro-ring resonator, which serves two functions simultaneously: 1) sensing the condensed water droplets via evanescent fields and 2) functioning as a highly accurate, in situ temperature sensor based on the thermo-optic effect (TOE). This device virtually eliminates most of the temperature-related errors that affect conventional “chilled-mirror” hygrometers. Moreover, this DPS outperforms conventional “chilled-mirror” hygrometers with respect to size, cost and response time, paving the way for on-chip dew point detection and extension to applications for which the conventional technology is unsuitable because of size, cost, and other constraints. PMID:27417734

  1. Comparison of Two Methodologies for Calibrating Satellite Instruments in the Visible and Near-Infrared

    NASA Technical Reports Server (NTRS)

    Barnes, Robert A.; Brown, Steven W.; Lykke, Keith R.; Guenther, Bruce; Butler, James J.; Schwarting, Thomas; Turpie, Kevin; Moyer, David; DeLuccia, Frank; Moeller, Christopher

    2015-01-01

    Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance responsivity in a two-step method. In the first step, the relative spectral response (RSR) of the instrument is determined using a nearly monochromatic light source such as a lamp-illuminated monochromator. These sources do not typically fill the field-of-view of the instrument nor act as calibrated sources of light. Consequently, they only provide a relative (not absolute) spectral response for the instrument. In the second step, the instrument views a calibrated source of broadband light, such as a lamp-illuminated integrating sphere. The RSR and the sphere absolute spectral radiance are combined to determine the absolute spectral radiance responsivity (ASR) of the instrument. More recently, a full-aperture absolute calibration approach using widely tunable monochromatic lasers has been developed. Using these sources, the ASR of an instrument can be determined in a single step on a wavelength-by-wavelength basis. From these monochromatic ASRs, the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as lamp-illuminated integrating spheres. In this work, the traditional broadband source-based calibration of the Suomi National Preparatory Project (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor is compared with the laser-based calibration of the sensor. Finally, the impact of the new full-aperture laser-based calibration approach on the on-orbit performance of the sensor is considered.

  2. Comparison of two methodologies for calibrating satellite instruments in the visible and near infrared

    PubMed Central

    Barnes, Robert A.; Brown, Steven W.; Lykke, Keith R.; Guenther, Bruce; Butler, James J.; Schwarting, Thomas; Moyer, David; Turpie, Kevin; DeLuccia, Frank; Moeller, Christopher

    2016-01-01

    Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance responsivity in a two-step method. In the first step, the relative spectral response (RSR) of the instrument is determined using a nearly monochromatic light source such as a lamp-illuminated monochromator. These sources do not typically fill the field-of-view of the instrument nor act as calibrated sources of light. Consequently, they only provide a relative (not absolute) spectral response for the instrument. In the second step, the instrument views a calibrated source of broadband light, such as a lamp-illuminated integrating sphere. The RSR and the sphere absolute spectral radiance are combined to determine the absolute spectral radiance responsivity (ASR) of the instrument. More recently, a full-aperture absolute calibration approach using widely tunable monochromatic lasers has been developed. Using these sources, the ASR of an instrument can be determined in a single step on a wavelength-by-wavelength basis. From these monochromatic ASRs, the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as integrating spheres. In this work, the traditional broadband source-based calibration of the Suomi National Preparatory Project (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor is compared with the laser-based calibration of the sensor. Finally, the impact of the new full-aperture laser-based calibration approach on the on-orbit performance of the sensor is considered. PMID:26836861

  3. Fast Coherent Differential Imaging for Exoplanet Imaging

    NASA Astrophysics Data System (ADS)

    Gerard, Benjamin; Marois, Christian; Galicher, Raphael; Veran, Jean-Pierre; Macintosh, B.; Guyon, O.; Lozi, J.; Pathak, P.; Sahoo, A.

    2018-06-01

    Direct detection and detailed characterization of exoplanets using extreme adaptive optics (ExAO) is a key science goal of future extremely large telescopes and space observatories. However, quasi-static wavefront errors will limit the sensitivity of this endeavor. Additional limitations for ground-based telescopes arise from residual AO-corrected atmospheric wavefront errors, generating short-lived aberrations that will average into a halo over a long exposure, also limiting the sensitivity of exoplanet detection. We develop the framework for a solution to both of these problems using the self-coherent camera (SCC), to be applied to ground-based telescopes, called Fast Atmospheric SCC Technique (FAST). Simulations show that for typical ExAO targets the FAST approach can reach ~100 times better in raw contrast than what is currently achieved with ExAO instruments if we extrapolate for an hour of observing time, illustrating that the sensitivity improvement from this method could play an essential role in the future ground-based detection and characterization of lower mass/colder exoplanets.

  4. Fast neutral beam ion source coupled to a Fourier transform ion cyclotron resonance mass spectrometer

    NASA Astrophysics Data System (ADS)

    Hill, Nicholas C.; Limbach, Patrick A.; Shomo, Ronald E., II; Marshall, Alan G.; Appelhans, Anthony D.; Delmore, James E.

    1991-11-01

    The coupling of an autoneutralizing SF-6 fast ion-beam gun to a Fourier transform ion cyclotron resonance (FT/ICR) mass spectrometer is described. The fast neutral beam provides for secondary-ion-type FT/ICR mass analysis [e.g., production of abundant pseudomolecular (M+H)+ ions] of involatile samples without the need for external ion injection, since ions are formed at the entrance to the ICR ion trap. The design, construction, and testing of the hybrid instrument are described. The feasibility of the experiment (for both broadband and high-resolution FT/ICR positive-ion mass spectra) is demonstrated with tetra-butylammonium bromide and a Tylenol■ sample. The ability to analyze high molecular weight polymers with high mass resolution is demonstrated for Teflon■. All of the advantages of the fast neutral beam ion source previously demonstrated with quadrupole mass analysis are preserved, and the additional advantages of FT/ICR mass analysis (e.g., high mass resolving power, ion trapping) are retained.

  5. Modeling of fast neutral-beam-generated ions and rotation effects on RWM stability in DIII-D plasmas

    DOE PAGES

    Turco, Francesca; Turnbull, Alan D.; Hanson, Jeremy M.; ...

    2015-10-15

    Here, validation results for the MARS-K code for DIII-D equilibria, predict that the absence of fast Neutral Beam (NB) generated ions leads to a plasma response ~40–60% higher than in NB-sustained H-mode plasmas when the no-wall β N limit is reached. In a β N scan, the MARS-K model with thermal and fast-ions, reproduces the experimental measurements above the no-wall limit, except at the highest β N where the phase of the plasma response is overestimated. The dependencies extrapolate unfavorably to machines such as ITER with smaller fast ion fractions since elevated responses in the absence of fast ions indicatemore » the potential onset of a resistive wall mode (RWM). The model was also tested for the effects of rotation at high β N, and recovers the measured response even when fast-ions are neglected, reversing the effect found in lower β N cases, but consistent with the higher β N results above the no-wall limit. The agreement in the response amplitude and phase for the rotation scan is not as good, and additional work will be needed to reproduce the experimental trends. In the case of current-driven instabilities, the magnetohydrodynamic spectroscopy system used to measure the plasma response reacts differently from that for pressure driven instabilities: the response amplitude remains low up to ~93% of the current limit, showing an abrupt increase only in the last ~5% of the current ramp. This makes it much less effective as a diagnostic for the approach to an ideal limit. However, the mode structure of the current driven RWM extends radially inwards, consistent with that in the pressure driven case for plasmas with q edge~2. This suggests that previously developed RWM feedback techniques together with the additional optimizations that enabled q edge~2 operation, can be applied to control of both current-driven and pressure-driven modes at high β N.« less

  6. NPY/AgRP neurons are not essential for feeding responses to glucoprivation.

    PubMed

    Luquet, Serge; Phillips, Colin T; Palmiter, Richard D

    2007-02-01

    Animals respond to hypoglycemia by eating and by stimulating gluconeogenesis. These responses to glucose deprivation are initiated by glucose-sensing neurons in the brain, but the neural circuits that control feeding behavior are not well established. Neurons in the arcuate region of the hypothalamus that express neuropeptide Y (NPY) and agouti-related protein (AgRP) have been implicated in mediating the feeding response to glucoprivation. We devised a method to selectively ablate these neurons in neonatal mice and then tested adult mice for their feeding responses to fasting, mild hypoglycemia, 2-deoxy-d-glucose and a ghrelin receptor agonist. Whereas the feeding response to the ghrelin receptor agonist was completely abrogated, the feeding response to glucoprivation was normal. The feeding response after a fast was attenuated when standard chow was available but normal with more palatable solid or liquid diet. We conclude that NPY/AgRP neurons are not necessary for generating or mediating the orexigenic response to glucose deficiency, but they are essential for the feeding response to ghrelin and refeeding on standard chow after a fast.

  7. INVESTIGATION OF OPEN-PATH FTIR FOR FAST DEPLOYMENT EMERGENCY RESPONSE TO CHEMICAL THREATS AND ACCIDENTS.

    EPA Science Inventory

    We have performed a series of experiments to determine the tradeoff in detection sensitivity for implementing design features for an Open-Path Fourier Transform Infrared (OP-FTIR) chemical analyzer that would be quick to deploy under emergency response conditions. The fast-deplo...

  8. Fast and Adaptive Lossless Onboard Hyperspectral Data Compression System

    NASA Technical Reports Server (NTRS)

    Aranki, Nazeeh I.; Keymeulen, Didier; Kimesh, Matthew A.

    2012-01-01

    Modern hyperspectral imaging systems are able to acquire far more data than can be downlinked from a spacecraft. Onboard data compression helps to alleviate this problem, but requires a system capable of power efficiency and high throughput. Software solutions have limited throughput performance and are power-hungry. Dedicated hardware solutions can provide both high throughput and power efficiency, while taking the load off of the main processor. Thus a hardware compression system was developed. The implementation uses a field-programmable gate array (FPGA). The implementation is based on the fast lossless (FL) compression algorithm reported in Fast Lossless Compression of Multispectral-Image Data (NPO-42517), NASA Tech Briefs, Vol. 30, No. 8 (August 2006), page 26, which achieves excellent compression performance and has low complexity. This algorithm performs predictive compression using an adaptive filtering method, and uses adaptive Golomb coding. The implementation also packetizes the coded data. The FL algorithm is well suited for implementation in hardware. In the FPGA implementation, one sample is compressed every clock cycle, which makes for a fast and practical realtime solution for space applications. Benefits of this implementation are: 1) The underlying algorithm achieves a combination of low complexity and compression effectiveness that exceeds that of techniques currently in use. 2) The algorithm requires no training data or other specific information about the nature of the spectral bands for a fixed instrument dynamic range. 3) Hardware acceleration provides a throughput improvement of 10 to 100 times vs. the software implementation. A prototype of the compressor is available in software, but it runs at a speed that does not meet spacecraft requirements. The hardware implementation targets the Xilinx Virtex IV FPGAs, and makes the use of this compressor practical for Earth satellites as well as beyond-Earth missions with hyperspectral instruments.

  9. Disaster response team FAST skills training with a portable ultrasound simulator compared to traditional training: pilot study.

    PubMed

    Paddock, Michael T; Bailitz, John; Horowitz, Russ; Khishfe, Basem; Cosby, Karen; Sergel, Michelle J

    2015-03-01

    Pre-hospital focused assessment with sonography in trauma (FAST) has been effectively used to improve patient care in multiple mass casualty events throughout the world. Although requisite FAST knowledge may now be learned remotely by disaster response team members, traditional live instructor and model hands-on FAST skills training remains logistically challenging. The objective of this pilot study was to compare the effectiveness of a novel portable ultrasound (US) simulator with traditional FAST skills training for a deployed mixed provider disaster response team. We randomized participants into one of three training groups stratified by provider role: Group A. Traditional Skills Training, Group B. US Simulator Skills Training, and Group C. Traditional Skills Training Plus US Simulator Skills Training. After skills training, we measured participants' FAST image acquisition and interpretation skills using a standardized direct observation tool (SDOT) with healthy models and review of FAST patient images. Pre- and post-course US and FAST knowledge were also assessed using a previously validated multiple-choice evaluation. We used the ANOVA procedure to determine the statistical significance of differences between the means of each group's skills scores. Paired sample t-tests were used to determine the statistical significance of pre- and post-course mean knowledge scores within groups. We enrolled 36 participants, 12 randomized to each training group. Randomization resulted in similar distribution of participants between training groups with respect to provider role, age, sex, and prior US training. For the FAST SDOT image acquisition and interpretation mean skills scores, there was no statistically significant difference between training groups. For US and FAST mean knowledge scores, there was a statistically significant improvement between pre- and post-course scores within each group, but again there was not a statistically significant difference between training groups. This pilot study of a deployed mixed-provider disaster response team suggests that a novel portable US simulator may provide equivalent skills training in comparison to traditional live instructor and model training. Further studies with a larger sample size and other measures of short- and long-term clinical performance are warranted.

  10. SiFAP: a Simple Sub-Millisecond Astronomical Photometer

    NASA Astrophysics Data System (ADS)

    Ambrosino, F.; Meddi, F.; Nesci, R.; Rossi, C.; Sclavi, S.; Bruni, I.

    2013-09-01

    A new fast photometer based on SiPM technology was developed at the University of Rome "La Sapienza" starting from 2009. A first prototype was successfully tested observing the Crab pulsar at the Loiano telescope of the Bologna Observatory. In this paper we illustrate the improvements we applied to our instrument, concerning new cooled commercial sensors, a new version of our custom dedicated electronics and an upgraded control timing software. Finally we report the results obtained with this instrument on December 2012 on the Crab pulsar at the Loiano telescope to show its goodness and capabilities.

  11. Aquarius Radiometer Status

    NASA Technical Reports Server (NTRS)

    Le Vine, D. M.; Piepmeier, J. R.; Dinnat, E. P.; de Matthaeis, P.; Utku, C.; Abraham, S.; Lagerloef, G.S.E.; Meissner, T.; Wentz, F.

    2014-01-01

    Aquarius was launched on June 10, 2011 as part of the Aquarius/SAC-D observatory and the instrument has been operating continuously since being turned on in August of the same year. The initial map of sea surface salinity was released one month later (September) and the quality of the retrieval has continuously improved since then. The Aquarius radiometers include several special features such as measurement of the third Stokes parameter, fast sampling, and careful thermal control, and a combined passive/active instrument. Aquarius is working well and in addition to helping measure salinity, the radiometer special features are generating new results.

  12. A large-strain, fast-response, and easy-to-manufacture electrothermal actuator based on laser-reduced graphene oxide

    NASA Astrophysics Data System (ADS)

    Zhang, Tian-Yu; Wang, Qian; Deng, Ning-Qin; Zhao, Hai-Ming; Wang, Dan-Yang; Yang, Zhen; Liu, Ying; Yang, Yi; Ren, Tian-Ling

    2017-09-01

    In this paper, we have developed a high-performance graphene electrothermal actuator (ETA). The fabrication method is easy, fast, environmentally friendly, and suitable for preparing both large-size and miniature graphene ETAs. When applied with the driving voltage of 65 V, the graphene ETA achieves a large bending angle of 270° with a fast response of 8 s and the recovery process costs 19 s. The large bending deformation is reversible and can be precisely controlled by the driving voltage. A simple robotic hand prepared by using a single graphene ETA can hold the object, which is more than ten times the weight of itself. By virtue of its large-strain, fast response, and easy-to-manufacture, we believe that the graphene ETA has tremendous potential in extensive applications involving biomimetic robotics, artificial muscles, switches, and microsensors in both macroscopic and microscopic fields.

  13. Robust fast controller design via nonlinear fractional differential equations.

    PubMed

    Zhou, Xi; Wei, Yiheng; Liang, Shu; Wang, Yong

    2017-07-01

    A new method for linear system controller design is proposed whereby the closed-loop system achieves both robustness and fast response. The robustness performance considered here means the damping ratio of closed-loop system can keep its desired value under system parameter perturbation, while the fast response, represented by rise time of system output, can be improved by tuning the controller parameter. We exploit techniques from both the nonlinear systems control and the fractional order systems control to derive a novel nonlinear fractional order controller. For theoretical analysis of the closed-loop system performance, two comparison theorems are developed for a class of fractional differential equations. Moreover, the rise time of the closed-loop system can be estimated, which facilitates our controller design to satisfy the fast response performance and maintain the robustness. Finally, numerical examples are given to illustrate the effectiveness of our methods. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  14. FRBCAT: The Fast Radio Burst Catalogue

    NASA Astrophysics Data System (ADS)

    Petroff, E.; Barr, E. D.; Jameson, A.; Keane, E. F.; Bailes, M.; Kramer, M.; Morello, V.; Tabbara, D.; van Straten, W.

    2016-09-01

    Here, we present a catalogue of known Fast Radio Burst sources in the form of an online catalogue, FRBCAT. The catalogue includes information about the instrumentation used for the observations for each detected burst, the measured quantities from each observation, and model-dependent quantities derived from observed quantities. To aid in consistent comparisons of burst properties such as width and signal-to-noise ratios, we have re-processed all the bursts for which we have access to the raw data, with software which we make available. The originally derived properties are also listed for comparison. The catalogue is hosted online as a Mysql database which can also be downloaded in tabular or plain text format for off-line use. This database will be maintained for use by the community for studies of the Fast Radio Burst population as it grows.

  15. High Frequency Design Considerations for the Large Detector Number and Small Form Factor Dual Electron Spectrometer of the Fast Plasma Investigation on NASA's Magnetospheric Multiscale Mission

    NASA Technical Reports Server (NTRS)

    Kujawski, Joseph T.; Gliese, Ulrik B.; Cao, N. T.; Zeuch, M. A.; White, D.; Chornay, D. J; Lobell, J. V.; Avanov, L. A.; Barrie, A. C.; Mariano, A. J.; hide

    2015-01-01

    Each half of the Dual Electron Spectrometer (DES) of the Fast Plasma Investigation (FPI) on NASA's Magnetospheric MultiScale (MMS) mission utilizes a microchannel plate Chevron stack feeding 16 separate detection channels each with a dedicated anode and amplifier/discriminator chip. The desire to detect events on a single channel with a temporal spacing of 100 ns and a fixed dead-time drove our decision to use an amplifier/discriminator with a very fast (GHz class) front end. Since the inherent frequency response of each pulse in the output of the DES microchannel plate system also has frequency components above a GHz, this produced a number of design constraints not normally expected in electronic systems operating at peak speeds of 10 MHz. Additional constraints are imposed by the geometry of the instrument requiring all 16 channels along with each anode and amplifier/discriminator to be packaged in a relatively small space. We developed an electrical model for board level interactions between the detector channels to allow us to design a board topology which gave us the best detection sensitivity and lowest channel to channel crosstalk. The amplifier/discriminator output was designed to prevent the outputs from one channel from producing triggers on the inputs of other channels. A number of Radio Frequency design techniques were then applied to prevent signals from other subsystems (e.g. the high voltage power supply, command and data handling board, and Ultraviolet stimulation for the MCP) from generating false events. These techniques enabled us to operate the board at its highest sensitivity when operated in isolation and at very high sensitivity when placed into the overall system.

  16. Spiky Fine Structure of Type III-like Radio Bursts in Absorption

    NASA Astrophysics Data System (ADS)

    Chernov, G. P.; Yan, Y. H.; Tan, C. M.; Chen, B.; Fu, Q. J.

    2010-03-01

    An uncommon fine structure in the radio spectrum consisting of bursts in absorption was observed with the Chinese Solar Broadband Radiospectrometer (SBRS) in the frequency range of 2.6 - 3.8 GHz during an X3.4/4B flare on 13 December 2006 in active region NOAA 10930 (S05W33). Usual fine structures in emission such as spikes, zebra stripes, and drifting fibers were observed at the peak of every new flare brightening. Within an hour at the decay phase of the event we observed bursts consisting of spikes in absorption, which pulsated periodically in frequency. Their instantaneous frequency bandwidths were found to be in the 75 MHz range. Moreover, in the strongest Type III-like bursts in absorption, the spikes showed stripes of the zebra-pattern (ZP) that drifted to higher frequencies. All spikes had the duration as short as down to the limit of the instrument resolution of ≈8 ms. The TRACE 195 Å images indicate that the magnetic reconnection at this moment occurred in the western edge of the flare loop arcade. Taking into account the presence of the reverse-drifting bursts in emission, in the course of the restoration of the magnetic structures in the corona, the acceleration of the beams of fast particles must have occurred both upward and downward at different heights. The upward beams will be captured by the magnetic trap, where the loss-cone distribution of fast particles (responsible for the emission of continuum and ZP) were formed. An additional injection of fast particles will fill the loss-cone later, breaking the loss-cone distribution. Therefore, the generation of continuum will be quenched at these moments, which was evidenced by the formation of bursts in absorption.

  17. Full-field dual-color 100-nm super-resolution imaging reveals organization and dynamics of mitochondrial and ER networks.

    PubMed

    Brunstein, Maia; Wicker, Kai; Hérault, Karine; Heintzmann, Rainer; Oheim, Martin

    2013-11-04

    Most structured illumination microscopes use a physical or synthetic grating that is projected into the sample plane to generate a periodic illumination pattern. Albeit simple and cost-effective, this arrangement hampers fast or multi-color acquisition, which is a critical requirement for time-lapse imaging of cellular and sub-cellular dynamics. In this study, we designed and implemented an interferometric approach allowing large-field, fast, dual-color imaging at an isotropic 100-nm resolution based on a sub-diffraction fringe pattern generated by the interference of two colliding evanescent waves. Our all-mirror-based system generates illumination pat-terns of arbitrary orientation and period, limited only by the illumination aperture (NA = 1.45), the response time of a fast, piezo-driven tip-tilt mirror (10 ms) and the available fluorescence signal. At low µW laser powers suitable for long-period observation of life cells and with a camera exposure time of 20 ms, our system permits the acquisition of super-resolved 50 µm by 50 µm images at 3.3 Hz. The possibility it offers for rapidly adjusting the pattern between images is particularly advantageous for experiments that require multi-scale and multi-color information. We demonstrate the performance of our instrument by imaging mitochondrial dynamics in cultured cortical astrocytes. As an illustration of dual-color excitation dual-color detection, we also resolve interaction sites between near-membrane mitochondria and the endoplasmic reticulum. Our TIRF-SIM microscope provides a versatile, compact and cost-effective arrangement for super-resolution imaging, allowing the investigation of co-localization and dynamic interactions between organelles--important questions in both cell biology and neurophysiology.

  18. The Wide Field Imager for Athena

    NASA Astrophysics Data System (ADS)

    Rau, A.; Nandra, K.; Meidinger, N.; Plattner, M.

    2017-10-01

    The Wide Field Imager (WFI) is one of the two scientific instruments of Athena, ESA's next large X-ray Observatory with launch in 2028. The instrument will provide two defining capabilities to the mission sensitive wide-field imaging spectroscopy and excellent high-count rate performance. It will do so with the use of two separate detectors systems, the Large Detector Array (LDA) optimized for its field of view (40'×40') with a 100 fold survey speed increase compared to existing X-ray missions, and the Fast Detector (FD) tweaked for high throughput and low pile-up for point sources as bright as the Crab. In my talk I will present the key performance parameters of the instrument and their links to the scientific goals of Athena and summarize the status of the ongoing development activities.

  19. A study of adaptation mechanisms based on ABR recorded at high stimulation rate.

    PubMed

    Valderrama, Joaquin T; de la Torre, Angel; Alvarez, Isaac; Segura, Jose Carlos; Thornton, A Roger D; Sainz, Manuel; Vargas, Jose Luis

    2014-04-01

    This paper analyzes the fast and slow mechanisms of adaptation through a study of latencies and amplitudes on ABR recorded at high stimulation rates using the randomized stimulation and averaging (RSA) technique. The RSA technique allows a separate processing of auditory responses, and is used, in this study, to categorize responses according to the interstimulus interval (ISI) of their preceding stimulus. The fast and slow mechanisms of adaptation are analyzed by the separated responses methodology, whose underlying principles and mathematical basis are described in detail. The morphology of the ABR is influenced by both fast and slow mechanisms of adaptation. These results are consistent with previous animal studies based on spike rate. Both fast and slow mechanisms of adaptation are present in all subjects. In addition, the distribution of the jitter and the sequencing of the stimuli may be critical parameters when obtaining reliable ABRs. The separated responses methodology enables for the first time the analysis of the fast and slow mechanisms of adaptation in ABR obtained at stimulation rates greater than 100 Hz. The non-invasive nature of this methodology is appropriate for its use in humans. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  20. The way to her heart? Response to romantic cues is dependent on hunger state and dieting history: An fMRI pilot study.

    PubMed

    Ely, Alice V; Childress, Anna Rose; Jagannathan, Kanchana; Lowe, Michael R

    2015-12-01

    Normal weight historical dieters (HDs) are prone to future weight gain, and show higher levels of brain activation in reward-related regions after having eaten than nondieters (NDs) in response to food stimuli (Ely, Childress, Jagannathan, & Lowe, 2014), a similar pattern to that seen in obesity. We hypothesized that HDs are differentially sensitive after eating to rewards in general, and thus extended prior findings by comparing the same groups' brain activation when viewing romantic pictures compared to neutral stimuli while being scanned in a blood oxygenation level-dependent (BOLD) fMRI paradigm in a fasted and fed state. Results show that 1) in fed relative to fasted conditions, both HDs and NDs were more responsive in areas related to reward and 2) in HDs, greater fed versus fasted activation extended to areas linked to perception and goal-directed behavior. HDs relative to NDs were more responsive to romantic cues in the superior frontal gyrus when fasted and the middle temporal gyrus when fed. This pattern of response is similar to HDs' activation when viewing highly palatable food cues, and is consistent with research showing overlapping brain-based responses to sex, drugs and food. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. From perception to action: phase-locked gamma oscillations correlate with reaction times in a speeded response task

    PubMed Central

    Fründ, Ingo; Busch, Niko A; Schadow, Jeanette; Körner, Ursula; Herrmann, Christoph S

    2007-01-01

    Background Phase-locked gamma oscillations have so far mainly been described in relation to perceptual processes such as sensation, attention or memory matching. Due to its very short latency (≈90 ms) such oscillations are a plausible candidate for very rapid integration of sensory and motor processes. Results We measured EEG in 13 healthy participants in a speeded reaction task. Participants had to press a button as fast as possible whenever a visual stimulus was presented. The stimulus was always identical and did not have to be discriminated from other possible stimuli. In trials in which the participants showed a fast response, a slow negative potential over central electrodes starting approximately 800 ms before the response and highly phase-locked gamma oscillations over central and posterior electrodes between 90 and 140 ms after the stimulus were observed. In trials in which the participants showed a slow response, no slow negative potential was observed and phase-locked gamma oscillations were significantly reduced. Furthermore, for slow response trials the phase-locked gamma oscillations were significantly delayed with respect to fast response trials. Conclusion These results indicate the relevance of phase-locked gamma oscillations for very fast (not necessarily detailed) integration processes. PMID:17439642

  2. Experimental and numerical analysis of penetration/removal response of endodontic instrument made of single crystal Cu-based SMA: comparison with NiTi SMA instruments

    NASA Astrophysics Data System (ADS)

    Vincent, M.; Xolin, P.; Gevrey, A.-M.; Thiebaud, F.; Engels-Deutsch, M.; Ben Zineb, T.

    2017-04-01

    This paper presents an experimental and numerical study showing that single crystal shape memory alloy (SMA) Cu-based endodontic instruments can lead to equivalent mechanical performances compared to NiTi-based instruments besides their interesting biological properties. Following a previous finite element analysis (FEA) of single crystal CuAlBe endodontic instruments (Vincent et al 2015 J. Mater. Eng. Perform. 24 4128-39), prototypes with the determined geometrical parameters were machined and experimentally characterized in continuous rotation during a penetration/removal (P/R) protocol in artificial canals. The obtained mechanical responses were compared to responses of NiTi endodontic files in the same conditions. In addition, FEA was conducted and compared with the experimental results to validate the adopted modeling and to evaluate the local quantities inside the instrument as the stress state and the distribution of volume fraction of martensite. The obtained results highlight that single crystal CuAlBe SMA prototypes show equivalent mechanical responses to its NiTi homologous prototypes in the same P/R experimental conditions.

  3. Irradiation Testing Vehicles for Fast Reactors from Open Test Assemblies to Closed Loops

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sienicki, James J.; Grandy, Christopher

    A review of irradiation testing vehicle approaches and designs that have been incorporated into past Sodium-Cooled Fast Reactors (SFRs) or envisioned for incorporation has been carried out. The objective is to understand the essential features of the approaches and designs so that they can inform test vehicle designs for a future U.S. Fast Test Reactor. Fast test reactor designs examined include EBR-II, FFTF, JOYO, BOR-60, PHÉNIX, JHR, and MBIR. Previous designers exhibited great ingenuity in overcoming design and operational challenges especially when the original reactor plant’s mission changed to an irradiation testing mission as in the EBRII reactor plant. Themore » various irradiation testing vehicles can be categorized as: Uninstrumented open assemblies that fit into core locations; Instrumented open test assemblies that fit into special core locations; Self-contained closed loops; and External closed loops. A special emphasis is devoted to closed loops as they are regarded as a very desirable feature of a future U.S. Fast Test Reactor. Closed loops are an important technology for irradiation of fuels and materials in separate controlled environments. The impact of closed loops on the design of fast reactors is also discussed in this report.« less

  4. Fast Bayesian approach for modal identification using free vibration data, Part I - Most probable value

    NASA Astrophysics Data System (ADS)

    Zhang, Feng-Liang; Ni, Yan-Chun; Au, Siu-Kui; Lam, Heung-Fai

    2016-03-01

    The identification of modal properties from field testing of civil engineering structures is becoming economically viable, thanks to the advent of modern sensor and data acquisition technology. Its demand is driven by innovative structural designs and increased performance requirements of dynamic-prone structures that call for a close cross-checking or monitoring of their dynamic properties and responses. Existing instrumentation capabilities and modal identification techniques allow structures to be tested under free vibration, forced vibration (known input) or ambient vibration (unknown broadband loading). These tests can be considered complementary rather than competing as they are based on different modeling assumptions in the identification model and have different implications on costs and benefits. Uncertainty arises naturally in the dynamic testing of structures due to measurement noise, sensor alignment error, modeling error, etc. This is especially relevant in field vibration tests because the test condition in the field environment can hardly be controlled. In this work, a Bayesian statistical approach is developed for modal identification using the free vibration response of structures. A frequency domain formulation is proposed that makes statistical inference based on the Fast Fourier Transform (FFT) of the data in a selected frequency band. This significantly simplifies the identification model because only the modes dominating the frequency band need to be included. It also legitimately ignores the information in the excluded frequency bands that are either irrelevant or difficult to model, thereby significantly reducing modeling error risk. The posterior probability density function (PDF) of the modal parameters is derived rigorously from modeling assumptions and Bayesian probability logic. Computational difficulties associated with calculating the posterior statistics, including the most probable value (MPV) and the posterior covariance matrix, are addressed. Fast computational algorithms for determining the MPV are proposed so that the method can be practically implemented. In the companion paper (Part II), analytical formulae are derived for the posterior covariance matrix so that it can be evaluated without resorting to finite difference method. The proposed method is verified using synthetic data. It is also applied to modal identification of full-scale field structures.

  5. Postprandial Metabolism and Appetite Do Not Differ between Lean Adults that Eat Breakfast or Morning Fast for 6 Weeks.

    PubMed

    Chowdhury, Enhad A; Richardson, Judith D; Tsintzas, Kostas; Thompson, Dylan; Betts, James A

    2018-01-01

    It remains unknown whether sustained daily feeding-fasting patterns modify the acute response to specific feedings on a given day. We conducted a randomized controlled trial to establish if daily breakfast consumption or fasting until noon modifies the acute metabolic and appetitive responses to a fixed breakfast and ad libitum lunch. With the use of a parallel group design, we randomly assigned 31 healthy, lean men and women (22-56 y) to 6 wk of either consuming ≥700 kcal of self-selected items before 1100 or fasting (0 kcal) until 1200 daily. Following 48 h of diet and physical activity standardization, we examined metabolic and appetite responses to a standardized breakfast and ad libitum lunch before and after the intervention. Data were analyzed using 3- and 2-way ANCOVA. Systemic concentrations of energy balance regulatory hormones total and acylated ghrelin, leptin, and peptide tyrosine-tyrosine) responded similarly to breakfast and lunch before and after 6 wk of either morning fasting or regular breakfast, with the exception of a tendency for increased glucagon-like peptide-1 concentrations from baseline to follow-up in the Breakfast Group compared with a decrease over that period in the Fasting Group [P = 0.06, partial eta squared value (ƞ2) = 0.16]. Subjective appetite sensations also did not differ over the course of the day, and ad libitum energy intake at lunch was not systematically affected by either intervention, decreasing by 27 kcal (95% CI: -203, 149 kcal) with fasting and by 77 kcal (95% CI: -210, 56 kcal) with breakfast. Similarly, glycemic, insulinemic, lipemic, and thermogenic responses to breakfast and lunch were very stable at baseline and follow-up and, thus, did not differ between treatment groups. Our results indicate that a sustained period of either extended morning fasting or eating a daily breakfast has minimal effect upon acute metabolic and appetite responses in lean adults. This trial was registered at www.isrctn.org as ISRCTN31521726. © 2018 American Society for Nutrition.

  6. How comparable are size-resolved particle number concentrations from different instruments?

    NASA Astrophysics Data System (ADS)

    Hornsby, K. E.; Pryor, S. C.

    2012-12-01

    The need for comparability of particle size resolved measurements originates from multiple drivers including: (i) Recent suggestions that air quality standards for particulate matter should migrate from being mass-based to incorporating number concentrations. This move would necessarily be predicated on measurement comparability which is absolutely critical to compliance determination. (ii) The need to quantify and diagnose causes of variability in nucleation and growth rates in nano-particle experiments conducted in different locations. (iii) Epidemiological research designed to identify key parameters in human health responses to fine particle exposure. Here we present results from a detailed controlled laboratory instrument inter-comparison experiment designed to investigate data comparability in the size range of 2.01-523.3 nm across a range of particle composition, modal diameter and absolute concentration. Particle size distributions were generated using a TSI model 3940 Aerosol Generation System (AGS) diluted using zero air, and sampled using four TSI Scanning Mobility Particle Spectrometer (SMPS) configurations and a TSI model 3091 Fast Mobility Particle Sizer (FMPS). The SMPS configurations used two Electrostatic Classifiers (EC) (model 3080) attached to either a Long DMA (LDMA) (model 3081) or a Nano DMA (NDMA) (model 3085) plumbed to either a TSI model 3025A Butanol Condensed Particle Counting (CPC) or a TSI model 3788 Water CPC. All four systems were run using both high and low flow conditions, and were operated with both the internal diffusion loss and multiple charge corrections turned on. The particle compositions tested were sodium chloride, ammonium nitrate and olive oil diluted in ethanol. Particles of all three were generated at three peak concentration levels (spanning the range observed at our experimental site), and three modal particle diameters. Experimental conditions were maintained for a period of 20 minutes to ensure experimental stationarity and in the data analysis only the middle 18 minutes of data are analyzed. Because of variations in the discretization of the different instrumental configurations, the data are analyzed both after being transformed onto a common size resolution and in terms of a fitted modal distribution. Diagnostic analysis are conducted to assess the impact of SMPS configuration on total number concentration, model geometric mean diameter and distribution dispersion. Preliminary results indicate that selection of DMA exerts the larger control over instrument response.

  7. Transcription factor assisted loading and enhancer dynamics dictate the hepatic fasting response.

    PubMed

    Goldstein, Ido; Baek, Songjoon; Presman, Diego M; Paakinaho, Ville; Swinstead, Erin E; Hager, Gordon L

    2017-03-01

    Fasting elicits transcriptional programs in hepatocytes leading to glucose and ketone production. This transcriptional program is regulated by many transcription factors (TFs). To understand how this complex network regulates the metabolic response to fasting, we aimed at isolating the enhancers and TFs dictating it. Measuring chromatin accessibility revealed that fasting massively reorganizes liver chromatin, exposing numerous fasting-induced enhancers. By utilizing computational methods in combination with dissecting enhancer features and TF cistromes, we implicated four key TFs regulating the fasting response: glucocorticoid receptor (GR), cAMP responsive element binding protein 1 (CREB1), peroxisome proliferator activated receptor alpha (PPARA), and CCAAT/enhancer binding protein beta (CEBPB). These TFs regulate fuel production by two distinctly operating modules, each controlling a separate metabolic pathway. The gluconeogenic module operates through assisted loading, whereby GR doubles the number of sites occupied by CREB1 as well as enhances CREB1 binding intensity and increases accessibility of CREB1 binding sites. Importantly, this GR-assisted CREB1 binding was enhancer-selective and did not affect all CREB1-bound enhancers. Single-molecule tracking revealed that GR increases the number and DNA residence time of a portion of chromatin-bound CREB1 molecules. These events collectively result in rapid synergistic gene expression and higher hepatic glucose production. Conversely, the ketogenic module operates via a GR-induced TF cascade, whereby PPARA levels are increased following GR activation, facilitating gradual enhancer maturation next to PPARA target genes and delayed ketogenic gene expression. Our findings reveal a complex network of enhancers and TFs that dynamically cooperate to restore homeostasis upon fasting. Published by Cold Spring Harbor Laboratory Press.

  8. Association between glucokinase regulatory protein (GCKR) and apolipoprotein A5 (APOA5) gene polymorphisms and triacylglycerol concentrations in fasting, postprandial, and fenofibrate-treated states.

    PubMed

    Perez-Martinez, Pablo; Corella, Dolores; Shen, Jian; Arnett, Donna K; Yiannakouris, Nikos; Tai, E Syong; Orho-Melander, Marju; Tucker, Katherine L; Tsai, Michael; Straka, Robert J; Province, Michael; Kai, Chew Suok; Perez-Jimenez, Francisco; Lai, Chao-Qiang; Lopez-Miranda, Jose; Guillen, Marisa; Parnell, Laurence D; Borecki, Ingrid; Kathiresan, Sekar; Ordovas, Jose M

    2009-01-01

    Hypertriglyceridemia is a risk factor for cardiovascular disease. Variation in the apolipoprotein A5 (APOA5) and glucokinase regulatory protein (GCKR) genes has been associated with fasting plasma triacylglycerol. We investigated the combined effects of the GCKR rs780094C-->T, APOA5 -1131T-->C, and APOA5 56C-->G single nucleotide polymorphisms (SNPs) on fasting triacylglycerol in several independent populations and the response to a high-fat meal and fenofibrate interventions. We used a cross-sectional design to investigate the association with fasting triacylglycerol in 8 populations from America, Asia, and Europe (n = 7,730 men and women) and 2 intervention studies in US whites (n = 1,061) to examine postprandial triacylglycerol after a high-fat meal and the response to fenofibrate. We defined 3 combined genotype groups: 1) protective (homozygous for the wild-type allele for all 3 SNPs); 2) intermediate (any mixed genotype not included in groups 1 and 3); and 3) risk (carriers of the variant alleles at both genes). Subjects within the risk group had significantly higher fasting triacylglycerol and a higher prevalence of hypertriglyceridemia than did subjects in the protective group across all populations. Moreover, subjects in the risk group had a greater postprandial triacylglycerol response to a high-fat meal and greater fenofibrate-induced reduction of fasting triacylglycerol than did the other groups, especially among persons with hypertriglyceridemia. Subjects with the intermediate genotype had intermediate values (P for trend <0.001). SNPs in GCKR and APOA5 have an additive effect on both fasting and postprandial triacylglycerol and contribute to the interindividual variability in response to fenofibrate treatment.

  9. Association between glucokinase regulatory protein (GCKR) and apolipoprotein A5 (APOA5) gene polymorphisms and triacylglycerol concentrations in fasting, postprandial, and fenofibrate-treated states123

    PubMed Central

    Perez-Martinez, Pablo; Corella, Dolores; Shen, Jian; Arnett, Donna K; Yiannakouris, Nikos; Tai, E Syong; Orho-Melander, Marju; Tucker, Katherine L; Tsai, Michael; Straka, Robert J; Province, Michael; Kai, Chew Suok; Perez-Jimenez, Francisco; Lai, Chao-Qiang; Lopez-Miranda, Jose; Guillen, Marisa; Parnell, Laurence D; Borecki, Ingrid; Kathiresan, Sekar; Ordovas, Jose M

    2009-01-01

    Background: Hypertriglyceridemia is a risk factor for cardiovascular disease. Variation in the apolipoprotein A5 (APOA5) and glucokinase regulatory protein (GCKR) genes has been associated with fasting plasma triacylglycerol. Objective: We investigated the combined effects of the GCKR rs780094C→T, APOA5 −1131T→C, and APOA5 56C→G single nucleotide polymorphisms (SNPs) on fasting triacylglycerol in several independent populations and the response to a high-fat meal and fenofibrate interventions. Design: We used a cross-sectional design to investigate the association with fasting triacylglycerol in 8 populations from America, Asia, and Europe (n = 7730 men and women) and 2 intervention studies in US whites (n = 1061) to examine postprandial triacylglycerol after a high-fat meal and the response to fenofibrate. We defined 3 combined genotype groups: 1) protective (homozygous for the wild-type allele for all 3 SNPs); 2) intermediate (any mixed genotype not included in groups 1 and 3); and 3) risk (carriers of the variant alleles at both genes). Results: Subjects within the risk group had significantly higher fasting triacylglycerol and a higher prevalence of hypertriglyceridemia than did subjects in the protective group across all populations. Moreover, subjects in the risk group had a greater postprandial triacylglycerol response to a high-fat meal and greater fenofibrate-induced reduction of fasting triacylglycerol than did the other groups, especially among persons with hypertriglyceridemia. Subjects with the intermediate genotype had intermediate values (P for trend <0.001). Conclusions: SNPs in GCKR and APOA5 have an additive effect on both fasting and postprandial triacylglycerol and contribute to the interindividual variability in response to fenofibrate treatment. PMID:19056598

  10. Frequency tagging to track the neural processing of contrast in fast, continuous sound sequences.

    PubMed

    Nozaradan, Sylvie; Mouraux, André; Cousineau, Marion

    2017-07-01

    The human auditory system presents a remarkable ability to detect rapid changes in fast, continuous acoustic sequences, as best illustrated in speech and music. However, the neural processing of rapid auditory contrast remains largely unclear, probably due to the lack of methods to objectively dissociate the response components specifically related to the contrast from the other components in response to the sequence of fast continuous sounds. To overcome this issue, we tested a novel use of the frequency-tagging approach allowing contrast-specific neural responses to be tracked based on their expected frequencies. The EEG was recorded while participants listened to 40-s sequences of sounds presented at 8Hz. A tone or interaural time contrast was embedded every fifth sound (AAAAB), such that a response observed in the EEG at exactly 8 Hz/5 (1.6 Hz) or harmonics should be the signature of contrast processing by neural populations. Contrast-related responses were successfully identified, even in the case of very fine contrasts. Moreover, analysis of the time course of the responses revealed a stable amplitude over repetitions of the AAAAB patterns in the sequence, except for the response to perceptually salient contrasts that showed a buildup and decay across repetitions of the sounds. Overall, this new combination of frequency-tagging with an oddball design provides a valuable complement to the classic, transient, evoked potentials approach, especially in the context of rapid auditory information. Specifically, we provide objective evidence on the neural processing of contrast embedded in fast, continuous sound sequences. NEW & NOTEWORTHY Recent theories suggest that the basis of neurodevelopmental auditory disorders such as dyslexia might be an impaired processing of fast auditory changes, highlighting how the encoding of rapid acoustic information is critical for auditory communication. Here, we present a novel electrophysiological approach to capture in humans neural markers of contrasts in fast continuous tone sequences. Contrast-specific responses were successfully identified, even for very fine contrasts, providing direct insight on the encoding of rapid auditory information. Copyright © 2017 the American Physiological Society.

  11. Rat psychomotor vigilance task with fast response times using a conditioned lick behavior

    PubMed Central

    Walker, Jennifer L.; Walker, Brendan M.; Fuentes, Fernanda Monjaraz; Rector, David M.

    2010-01-01

    Investigations into the physiological mechanisms of sleep control require an animal psychomotor vigilance task (PVT) with fast response times (<300ms). Rats provide a good PVT model since whisker stimulation produces a rapid and robust cortical evoked response, and animals can be trained to lick following stimulation. Our prior experiments used deprivation-based approaches to maximize motivation for operant conditioned responses. However, deprivation can influence physiological and neurobehavioral effects. In order to maintain motivation without water deprivation, we conditioned rats for immobilization and head restraint, then trained them to lick for a 10% sucrose solution in response to whisker stimulation. After approximately 8 training sessions, animals produced greater than 80% correct hits to the stimulus. Over the course of training, reaction times became faster and correct hits increased. Performance in the PVT was examined after 3, 6 and 12 hours of sleep deprivation achieved by gentle handling. A significant decrease in percent correct hits occurred following 6 and 12 hours of sleep deprivation and reaction times increased significantly following 12 hours of sleep deprivation. While behaviorally the animals appeared to be awake, we observed significant increases in EEG delta power prior to misses. The rat PVT with fast response times allows investigation of sleep deprivation effects, time on task and pharmacological agents. Fast response times also allow closer parallel studies to ongoing human protocols. PMID:20696188

  12. Risk of falls in older people during fast-walking--the TASCOG study.

    PubMed

    Callisaya, M L; Blizzard, L; McGinley, J L; Srikanth, V K

    2012-07-01

    To investigate the relationship between fast-walking and falls in older people. Individuals aged 60-86 years were randomly selected from the electoral roll (n=176). Gait speed, step length, cadence and a walk ratio were recorded during preferred- and fast-walking using an instrumented walkway. Falls were recorded prospectively over 12 months. Log multinomial regression was used to estimate the relative risk of single and multiple falls associated with gait variables during fast-walking and change between preferred- and fast-walking. Covariates included age, sex, mood, physical activity, sensorimotor and cognitive measures. The risk of multiple falls was increased for those with a smaller walk ratio (shorter steps, faster cadence) during fast-walking (RR 0.92, CI 0.87, 0.97) and greater reduction in the walk ratio (smaller increase in step length, larger increase in cadence) when changing to fast-walking (RR 0.73, CI 0.63, 0.85). These gait patterns were associated with poorer physiological and cognitive function (p<0.05). A higher risk of multiple falls was also seen for those in the fastest quarter of gait speed (p=0.01) at fast-walking. A trend for better reaction time, balance, memory and physical activity for higher categories of gait speed was stronger for fallers than non-fallers (p<0.05). Tests of fast-walking may be useful in identifying older individuals at risk of multiple falls. There may be two distinct groups at risk--the frail person with short shuffling steps, and the healthy person exposed to greater risk. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. 78 FR 50422 - Medical Devices; Availability of Safety and Effectiveness Summaries for Premarket Approval...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-19

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket Nos. FDA-2013-M-0462... Wolanski, Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Ave..... ABI 7500 Fast DX Real-Time PCR Instrument. P060028, FDA-2013-M-0738..... Mentor Worldwide LLC...

  14. 76 FR 5330 - University of Chicago, et al.; Notice of Decision on Applications for Duty-Free Entry of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-31

    .... Instrument: Pilatus 100K Pixel Detector System. Manufacturer: Dectris Ltd., Switzerland. Intended Use: See... detection scheme), high dynamic range (20- bits), and fast readout speeds. Docket Number: 10-068. Applicant... System. Manufacturer: Dectris Ltd., Switzerland. Intended Use: See Notice at 75 FR 82372, December 30...

  15. Measuring Effects Of Lightning On Power And Telephone Lines

    NASA Technical Reports Server (NTRS)

    Jafferis, William; Thompson, E. M.; Medelius, P.; Rubinstein, M.; Tzeng, A.

    1992-01-01

    Spherical antenna senses both horizontal and vertical fields simultaneously. Measures "fast" components of electric field used in conjunction with other equipment, including antenna measuring "slow" vertical component of electric field; microphone that senses thunder; cameras making visual records, which locate lightning; magnetic-field sensor; optical sensors; and instruments measuring speed and direction of wind.

  16. Fast imaging diagnostics on the C-2U advanced beam-driven field-reversed configuration device

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Granstedt, E. M., E-mail: egranstedt@trialphaenergy.com; Petrov, P.; Knapp, K.

    2016-11-15

    The C-2U device employed neutral beam injection, end-biasing, and various particle fueling techniques to sustain a Field-Reversed Configuration (FRC) plasma. As part of the diagnostic suite, two fast imaging instruments with radial and nearly axial plasma views were developed using a common camera platform. To achieve the necessary viewing geometry, imaging lenses were mounted behind re-entrant viewports attached to welded bellows. During gettering, the vacuum optics were retracted and isolated behind a gate valve permitting their removal if cleaning was necessary. The axial view incorporated a stainless-steel mirror in a protective cap assembly attached to the vacuum-side of the viewport.more » For each system, a custom lens-based, high-throughput optical periscope was designed to relay the plasma image about half a meter to a high-speed camera. Each instrument also contained a remote-controlled filter wheel, set between shots to isolate a particular hydrogen or impurity emission line. The design of the camera platform, imaging performance, and sample data for each view is presented.« less

  17. Development Of Methodologies Using PhabrOmeter For Fabric Drape Evaluation

    NASA Astrophysics Data System (ADS)

    Lin, Chengwei

    Evaluation of fabric drape is important for textile industry as it reveals the aesthetic and functionality of the cloth and apparel. Although many fabric drape measuring methods have been developed for several decades, they are falling behind the need for fast product development by the industry. To meet the requirement of industries, it is necessary to develop an effective and reliable method to evaluate fabric drape. The purpose of the present study is to determine if PhabrOmeter can be applied to fabric drape evaluation. PhabrOmeter is a fabric sensory performance evaluating instrument which is developed to provide fast and reliable quality testing results. This study was sought to determine the relationship between fabric drape and other fabric attributes. In addition, a series of conventional methods including AATCC standards, ASTM standards and ISO standards were used to characterize the fabric samples. All the data were compared and analyzed with linear correlation method. The results indicate that PhabrOmeter is reliable and effective instrument for fabric drape evaluation. Besides, some effects including fabric structure, testing directions were considered to examine their impact on fabric drape.

  18. Fast imaging diagnostics on the C-2U advanced beam-driven field-reversed configuration device

    NASA Astrophysics Data System (ADS)

    Granstedt, E. M.; Petrov, P.; Knapp, K.; Cordero, M.; Patel, V.

    2016-11-01

    The C-2U device employed neutral beam injection, end-biasing, and various particle fueling techniques to sustain a Field-Reversed Configuration (FRC) plasma. As part of the diagnostic suite, two fast imaging instruments with radial and nearly axial plasma views were developed using a common camera platform. To achieve the necessary viewing geometry, imaging lenses were mounted behind re-entrant viewports attached to welded bellows. During gettering, the vacuum optics were retracted and isolated behind a gate valve permitting their removal if cleaning was necessary. The axial view incorporated a stainless-steel mirror in a protective cap assembly attached to the vacuum-side of the viewport. For each system, a custom lens-based, high-throughput optical periscope was designed to relay the plasma image about half a meter to a high-speed camera. Each instrument also contained a remote-controlled filter wheel, set between shots to isolate a particular hydrogen or impurity emission line. The design of the camera platform, imaging performance, and sample data for each view is presented.

  19. Fasting suppresses T cell-mediated immunity in female Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Xu, De-Li; Wang, De-Hua

    2010-01-01

    Immune defense is important for organisms' survival and fitness. Small mammals in temperate zone often face seasonal food shortages. Generally fasting can suppress immune function in laboratory rodents and little information is available for wild rodents. The present study tested the hypothesis that Mongolian gerbils (Meriones unguiculatus) could inhibit T cell-mediated immunity to adapt to acute fasting. Forty-two females were divided into the fed and fasted groups, in which the latter was deprived of food for 3days. After 66h fasting, half of the gerbils in each group were injected with phosphate buffered saline or phytohaemagglutinin (PHA) solution. T cell-mediated immunity assessed by PHA response was suppressed in the fasted gerbils compared with the fed gerbils. The fasted gerbils had lower body fat mass, wet and dry thymus mass, dry spleen mass, white blood cells, serum leptin and blood glucose concentrations, but higher corticosterone concentrations than those of the controls. Moreover, PHA response was positively correlated with body fat mass and serum leptin levels in the immunochallenged groups. Taken together, acute fasting leads to immunosuppression, which might be caused by low body fat mass and low serum leptin concentrations in female Mongolian gerbils.

  20. FGF21 is dispensable for hypothermia induced by fasting in mice.

    PubMed

    Oishi, Katsutaka; Sakamoto, Katsuhiko; Konishi, Morichika; Murata, Yusuke; Itoh, Nobuyuki; Sei, Hiroyoshi

    2010-01-01

    Fibroblast growth factor 21 (FGF21) is a key metabolic regulator that is induced by peroxisome proliferator-activated receptor alpha (PPARalpha) activation in response to fasting. We recently reported that bezafibrate, a pan-agonist of PPARs, decreases body temperature late at night through hypothalamic neuropeptide Y (NPY) activation and others have shown that mice overexpressing FGF21 are prone to torpor. We examined whether FGF21 is essential for fasting-induced hypothermia using FGF21 knockout (KO) mice. Acute fasting decreased body temperature late at night accompanied by the induction of hepatic FGF21 and hypothalamic NPY expression in wild-type mice. A deficiency of FGF21 affected neither fasting-induced hypothermia nor hypothalamic NPY induction. Fasting enhanced locomotor activity in both genotypes. On the other hand, a deficiency of FGF21 significantly attenuated chronic hypothermia and hypoactivity induced by a ketogenic diet (KD). Our findings suggest that FGF21 is not essential for the hypothermia that is associated with the early stages of fasting, although it might be involved in the adaptive response of body temperature to chronic starvation.

  1. Fast Plasma Instrument for MMS: Data Compression Simulation Results

    NASA Astrophysics Data System (ADS)

    Barrie, A.; Adrian, M. L.; Yeh, P.; Winkert, G.; Lobell, J.; Vinas, A. F.; Simpson, D. G.

    2009-12-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eight (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6° x 180° fields-of-view (FOV) are set 90° apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45° x 180° fan about the its nominal viewing (0° deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the diffusion regions of reconnection, the highest temporal/spatial resolution mode of FPI results in the DES complement of a given spacecraft generating 6.5-Mb s-1 of electron data while the DIS generates 1.1-Mb s-1 of ion data yielding an FPI total data rate of 6.6-Mb s-1. The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. Currently, the FPI data rate allocation to the CIDP is 1.5-Mb s-1. Consequently, the FPI-IDPU must employ data/image compression to meet this CIDP telemetry allocation. Here, we present updated simulations of the CCSDS 122.0-B-1 algorithm-based compression of the FPI-DES electron data as well as the FPI-DIS ion data. Compression analysis is based upon a seed of re-processed Cluster/PEACE electron measurements and Cluster/CIS ion measurements. Topics to be discussed include: (i) Review of compression algorithm; (ii) Data quality; (iii) Data formatting/organization; (iv) Compression optimization; (v) Investigation of pseudo-log precompression; and (vi) Analysis of compression effectiveness for burst mode as well as fast survey mode data packets for both electron and ion data We conclude with a presentation of the current base-lined FPI data compression approach.

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thurmond, Kyle; Loparo, Zachary; Partridge, Jr., William P.

    Here, a sensor was developed for simultaneous measurements of carbon monoxide (CO) and carbon dioxide (CO 2) fluctuations in internal combustion engine exhaust gases. This sensor utilizes low-cost and compact light-emitting diodes (LEDs) that emit in the 3–5 µm wavelength range. An affordable, fast response sensor that can measure these gases has a broad application that can lead to more efficient, fuel-flexible engines and regulation of harmful emissions. Light emission from LEDs is spectrally broader and more spatially divergent when compared to that of lasers, which presented many design challenges. Optical design studies addressed some of the non-ideal characteristics ofmore » the LED emissions. Measurements of CO and CO 2 were conducted using their fundamental absorption bands centered at 4.7 µm and 4.3 µm, respectively, while a 3.6 µm reference LED was used to account for scattering losses (due to soot, window deposits, etc.) common to the three measurement LEDs. Instrument validation and calibration was performed using a laboratory flow cell and bottled-gas mixtures. The sensor was able to detect CO 2 and CO concentration changes as small as 30 ppm and 400 ppm, respectively. Because of the many control and monitor species with infra-red absorption features, which can be measured using the strategy described, this work demonstrates proof of concept for a wider range of fast (250 Hz) and low-cost sensors for gas measurement and process monitoring.« less

  3. Studying the spatial variability of Cr in agricultural field using both particle induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA) technique

    NASA Astrophysics Data System (ADS)

    Cruvinel, Paulo E.; Crestana, Sílvio; Artaxo, Paulo; Martins, JoséV.; Armelin, Maria JoséA.

    1996-04-01

    In the field of soil physics, a technique which permits a non-destructive, accurate and fast elemental analysis with a minimum of sample preparation effort is often desired. Although trace elements are minor components of the solid phase, they play an important role in soil fertility. Cr is of nutritional importance because it is a required element in human and animal nutrition. The immobility of Cr may be responsible for an inadequate Cr supply to plants. This work not only demonstrates the suitability of PIXE as a fast and non-destructive technique, useful to measure Cr content in soil samples, but also outlines a study of spatial variability of that element in agricultural field. To demonstrate the capability of the method soil samples were collected in a 5000 m 2 agricultural field. The soil samples were analyzed using both PIXE and INAA techniques. Besides, a Fourier interpolation technique was used to verify the distribution of Cr along of the sampled field. INAA was carried out by means of the γ-ray emitted by 51Cr(320 keV). Results show that there is a good linear relationship between the elemental concentration of Cr obtained using those techniques, i.e. a correlation coefficient of r2 = 0.82 was achieved.

  4. Evaluation of the response of tritium-in-air instrumentation to HT in dry and humid conditions and to HTO vapor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phillips, H.; Dean, J.; Privas, E.

    2015-03-15

    Nuclear plant operators (power generation, decommissioning and reprocessing operations) are required to monitor releases of tritium species for regulatory compliance and radiation protection purposes. Tritium monitoring is performed using tritium-in-air gas monitoring instrumentation based either on flow-through ion chambers or proportional counting systems. Tritium-in-air monitors are typically calibrated in dry conditions but in service may operate at elevated levels of relative humidity. The NPL (National Physical Laboratory) radioactive gas-in-air calibration system has been used to study the effect of humidity on the response to tritium of two tritium-in-air ion chamber based monitors and one proportional counting system which uses amore » P10/air gas mixture. The response of these instruments to HTO vapour has also been evaluated. In each case, instrument responses were obtained for HT in dry conditions (relative humidity (RH) about 2%), HT in 45% RH, and finally HTO at 45% RH. Instrumentation response to HT in humid conditions has been found to slightly exceed that in dry conditions. (authors)« less

  5. Age-related change in fast adaptation mechanisms measured with the scotopic full-field ERG.

    PubMed

    Tillman, Megan A; Panorgias, Athanasios; Werner, John S

    2016-06-01

    To quantify the response dynamics of fast adaptation mechanisms of the scotopic ERG in younger and older adults using full-field m-sequence flash stimulation. Scotopic ERGs were measured for a series of flashes separated by 65 ms over a range of 260 ms in 16 younger (20-26, 22.2 ± 2.1; range mean ±1 SD) and 16 older (65-85, 71.2 ± 7) observers without retinal pathology. A short-wavelength (λ peak = 442 nm) LED was used for scotopic stimulation, and the flashes ranged from 0.0001 to 0.01 cd s m(-2). The complete binary kernel series was derived from the responses to the m-sequence flash stimulation, and the first- and second-order kernel responses were analyzed. The first-order kernel represented the response to a single, isolated flash, while the second-order kernels reflected the adapted flash responses that followed a single flash by one or more base intervals. B-wave amplitudes of the adapted flash responses were measured and plotted as a function of interstimulus interval to describe the recovery of the scotopic ERG. A linear function was fitted to the linear portion of the recovery curve, and the slope of the line was used to estimate the rate of fast adaptation recovery. The amplitudes of the isolated flash responses and rates of scotopic fast adaptation recovery were compared between the younger and older participants using a two-way ANOVA. The isolated flash responses and rates of recovery were found to be significantly lower in the older adults. However, there was no difference between the two age groups in response amplitude or recovery rate after correcting for age-related changes in the density of the ocular media. These results demonstrated that the rate of scotopic fast adaptation recovery of normal younger and older adults is similar when stimuli are equated for retinal illuminance.

  6. A near-infrared SETI experiment: instrument overview

    NASA Astrophysics Data System (ADS)

    Wright, Shelley A.; Werthimer, Dan; Treffers, Richard R.; Maire, Jérôme; Marcy, Geoffrey W.; Stone, Remington P. S.; Drake, Frank; Meyer, Elliot; Dorval, Patrick; Siemion, Andrew

    2014-07-01

    We are designing and constructing a new SETI (Search for Extraterrestrial Intelligence) instrument to search for direct evidence of interstellar communications via pulsed laser signals at near-infrared wavelengths. The new instrument design builds upon our past optical SETI experiences, and is the first step toward a new, more versatile and sophisticated generation of very fast optical and near-infrared pulse search devices. We present our instrumental design by giving an overview of the opto-mechanical design, detector selection and characterization, signal processing, and integration procedure. This project makes use of near-infrared (950 - 1650 nm) discrete amplification Avalanche Photodiodes (APD) that have > 1 GHz bandwidths with low noise characteristics and moderate gain (~104). We have investigated the use of single versus multiple detectors in our instrument (see Maire et al., this conference), and have optimized the system to have both high sensitivity and low false coincidence rates. Our design is optimized for use behind a 1m telescope and includes an optical camera for acquisition and guiding. A goal is to make our instrument relatively economical and easy to duplicate. We describe our observational setup and our initial search strategies for SETI targets, and for potential interesting compact astrophysical objects.

  7. Increasing use of high-speed digital imagery as a measurement tool on test and evaluation ranges

    NASA Astrophysics Data System (ADS)

    Haddleton, Graham P.

    2001-04-01

    In military research and development or testing there are various fast and dangerous events that need to be recorded and analysed. High-speed cameras allow the capture of movement too fast to be recognised by the human eye, and provide data that is essential for the analysis and evaluation of such events. High-speed photography is often the only type of instrumentation that can be used to record the parameters demanded by our customers. I will show examples where this applied cinematography is used not only to provide a visual record of events, but also as an essential measurement tool.

  8. Sampling phasic dopamine signaling with fast-scan cyclic voltammetry in awake behaving rats

    PubMed Central

    Fortin, SM; Cone, JJ; Ng-Evans, S; McCutcheon, JE; Roitman, MF

    2015-01-01

    Fast-scan cyclic voltammetry (FSCV) is an electrochemical technique which permits the in vivo measurement of extracellular fluctuations in multiple chemical species. The technique is frequently utilized to sample sub-second (phasic) concentration changes of the neurotransmitter dopamine in awake and behaving rats. Phasic dopamine signaling is implicated in reinforcement, goal-directed behavior, and locomotion and FSCV has been used to investigate how rapid changes in striatal dopamine concentration contribute to these and other behaviors. This unit describes the instrumentation and construction, implantation, and use of necessary components required to sample and analyze dopamine concentration changes in awake rats with FSCV. PMID:25559005

  9. Mechanics of the fast-start: muscle function and the role of intramuscular pressure in the escape behavior of amia calva and polypterus palmas

    PubMed

    Westneat; Hale; Mchenry; Long

    1998-11-01

    The fast-start escape response is a rapid, powerful body motion used to generate high accelerations of the body in virtually all fishes. Although the neurobiology and behavior of the fast-start are often studied, the patterns of muscle activity and muscle force production during escape are less well understood. We studied the fast-starts of two basal actinopterygian fishes (Amia calva and Polypterus palmas) to investigate the functional morphology of the fast-start and the role of intramuscular pressure (IMP) in escape behavior. Our goals were to determine whether IMP increases during fast starts, to look for associations between muscle activity and elevated IMP, and to determine the functional role of IMP in the mechanics of the escape response. We simultaneously recorded the kinematics, muscle activity patterns and IMP of four A. calva and three P. palmas during the escape response. Both species generated high IMPs of up to 90 kPa (nearly 1 atmosphere) above ambient during the fast-start. The two species showed similar pressure magnitudes but had significantly different motor patterns and escape performance. Stage 1 of the fast-start was generated by simultaneous contraction of locomotor muscle on both sides of the body, although electromyogram amplitudes on the contralateral (convex) side of the fish were significantly lower than on the ipsilateral (concave) side. Simultaneous recordings of IMP, escape motion and muscle activity suggest that pressure change is caused by the contraction and radial swelling of cone-shaped myomeres. We develop a model of IMP production that incorporates myomere geometry, the concept of constant-volume muscular hydrostats, the relationship between fiber angle and muscle force, and the forces that muscle fibers produce. The timing profile of pressure change, behavior and muscle action indicates that elevated muscle pressure is a mechanism of stiffening the body and functions in force transmission during the escape response.

  10. Fast to forgive, slow to retaliate: intuitive responses in the ultimatum game depend on the degree of unfairness.

    PubMed

    Ferguson, Eamonn; Maltby, John; Bibby, Peter A; Lawrence, Claire

    2014-01-01

    Evolutionary accounts have difficulty explaining why people cooperate with anonymous strangers they will never meet. Recently models, focusing on emotional processing, have been proposed as a potential explanation, with attention focusing on a dual systems approach based on system 1 (fast, intuitive, automatic, effortless, and emotional) and system 2 (slow, reflective, effortful, proactive and unemotional). Evidence shows that when cooperation is salient, people are fast (system 1) to cooperate, but with longer delays (system 2) they show greed. This is interpreted within the framework of the social heuristic hypothesis (SHH), whereby people overgeneralize potentially advantageous intuitively learnt and internalization social norms to 'atypical' situations. We extend this to explore intuitive reactions to unfairness by integrating the SHH with the 'fast to forgive, slow to anger' (FFSA) heuristic. This suggests that it is advantageous to be prosocial when facing uncertainty. We propose that whether or not someone intuitively shows prosociality (cooperation) or retaliation is moderated by the degree (certainty) of unfairness. People should intuitively cooperate when facing mild levels of unfairness (fast to forgive) but when given longer to decide about another's mild level of unfairness should retaliate (slow to anger). However, when facing severe levels of unfairness, the intuitive response is always retaliation. We test this using a series of one-shot ultimatum games and manipulate level of offer unfairness (50:50 60:40, 70:30, 80:20, 90:10) and enforced time delays prior to responding (1s, 2s, 8s, 15s). We also measure decision times to make responses after the time delays. The results show that when facing mildly unfair offers (60:40) people are fast (intuitive) to cooperate but with longer delays reject these mildly unfair offers: 'fast to forgive, and slow to retaliate'. However, for severely unfair offers (90:10) the intuitive and fast response is to always reject.

  11. Fast to Forgive, Slow to Retaliate: Intuitive Responses in the Ultimatum Game Depend on the Degree of Unfairness

    PubMed Central

    Ferguson, Eamonn; Maltby, John; Bibby, Peter A.; Lawrence, Claire

    2014-01-01

    Evolutionary accounts have difficulty explaining why people cooperate with anonymous strangers they will never meet. Recently models, focusing on emotional processing, have been proposed as a potential explanation, with attention focusing on a dual systems approach based on system 1 (fast, intuitive, automatic, effortless, and emotional) and system 2 (slow, reflective, effortful, proactive and unemotional). Evidence shows that when cooperation is salient, people are fast (system 1) to cooperate, but with longer delays (system 2) they show greed. This is interpreted within the framework of the social heuristic hypothesis (SHH), whereby people overgeneralize potentially advantageous intuitively learnt and internalization social norms to ‘atypical’ situations. We extend this to explore intuitive reactions to unfairness by integrating the SHH with the ‘fast to forgive, slow to anger’ (FFSA) heuristic. This suggests that it is advantageous to be prosocial when facing uncertainty. We propose that whether or not someone intuitively shows prosociality (cooperation) or retaliation is moderated by the degree (certainty) of unfairness. People should intuitively cooperate when facing mild levels of unfairness (fast to forgive) but when given longer to decide about another's mild level of unfairness should retaliate (slow to anger). However, when facing severe levels of unfairness, the intuitive response is always retaliation. We test this using a series of one-shot ultimatum games and manipulate level of offer unfairness (50:50 60:40, 70:30, 80:20, 90:10) and enforced time delays prior to responding (1s, 2s, 8s, 15s). We also measure decision times to make responses after the time delays. The results show that when facing mildly unfair offers (60:40) people are fast (intuitive) to cooperate but with longer delays reject these mildly unfair offers: ‘fast to forgive, and slow to retaliate’. However, for severely unfair offers (90:10) the intuitive and fast response is to always reject. PMID:24820479

  12. Fundamentals of Materials, Techniques, and Instrumentation for OSL and FNTD Dosimetry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akselrod, M. S.

    The optically stimulated luminescence (OSL) technique has already become a successful commercial tool in personal radiation dosimetry, medical dosimetry, diagnostic imaging, geological and archeological dating. This review briefly describes the history and fundamental principles of OSL materials, methods and instrumentation. The advantages of OSL technology and instrumentation in comparison with thermoluminescent technique are analyzed. Progress in material and detector engineering has allowed new and promising developments regarding OSL applications in the medical field. Special attention is dedicated to Al{sub 2}O{sub 3}:C as a material of choice for many dosimetric applications. Different aspects of OSL theory, materials optical and dosimetric properties,more » instrumentation, and data processing algorithms are described. The next technological breakthrough was done with Fluorescent Nuclear Track Detectors (FNTD) that have some important advantages in measuring fast neutron and high energy heavy charge particles that have become the latest tool in radiation therapy. New Mg-doped aluminum oxide crystals and novel type of imaging instrumentation for FNTD technology are discussed with regard to application in mixed neutron-gamma fields, medical dosimetry and radiobiological research.« less

  13. Fundamentals of Materials, Techniques, and Instrumentation for OSL and FNTD Dosimetry

    NASA Astrophysics Data System (ADS)

    Akselrod, M. S.

    2011-05-01

    The optically stimulated luminescence (OSL) technique has already become a successful commercial tool in personal radiation dosimetry, medical dosimetry, diagnostic imaging, geological and archeological dating. This review briefly describes the history and fundamental principles of OSL materials, methods and instrumentation. The advantages of OSL technology and instrumentation in comparison with thermoluminescent technique are analyzed. Progress in material and detector engineering has allowed new and promising developments regarding OSL applications in the medical field. Special attention is dedicated to Al2O3:C as a material of choice for many dosimetric applications. Different aspects of OSL theory, materials optical and dosimetric properties, instrumentation, and data processing algorithms are described. The next technological breakthrough was done with Fluorescent Nuclear Track Detectors (FNTD) that have some important advantages in measuring fast neutron and high energy heavy charge particles that have become the latest tool in radiation therapy. New Mg-doped aluminum oxide crystals and novel type of imaging instrumentation for FNTD technology are discussed with regard to application in mixed neutron-gamma fields, medical dosimetry and radiobiological research.

  14. Construction and Validation of a Measurement Instrument for Attitudes towards Teamwork.

    PubMed

    Mendo-Lázaro, Santiago; Polo-Del-Río, María I; Iglesias-Gallego, Damián; Felipe-Castaño, Elena; León-Del-Barco, Benito

    2017-01-01

    Cooperative, collaborative learning and other forms of group learning methods are increasingly used in classrooms. Knowing students' attitudes toward teamwork has great value since they influence the students' learning results as well as their social development. So it is necessary to have robust instruments to provide a better understanding of these attitudes and preferences concerning teamwork. Such instruments also help to identify the factors that promote positive or negative attitudes within the context of group activities. Using a sample of 750 first and second year university students studying a degree in Kindergarten, Primary and Social Education, an instrument measuring attitudes toward team learning has been developed. Two distinct factors were obtained through various factorial analyses and structural equations: Academic attitudes and Social and emotional attitudes . Our study reveals that the instrument is both valid and reliable. Its application is both simple and fast and it has important implications for planning teaching and learning activities that contribute to an improvement in attitudes as well as the practice of teaching in the context of learning through teamwork.

  15. Construction and Validation of a Measurement Instrument for Attitudes towards Teamwork

    PubMed Central

    Mendo-Lázaro, Santiago; Polo-del-Río, María I.; Iglesias-Gallego, Damián; Felipe-Castaño, Elena; León-del-Barco, Benito

    2017-01-01

    Cooperative, collaborative learning and other forms of group learning methods are increasingly used in classrooms. Knowing students’ attitudes toward teamwork has great value since they influence the students’ learning results as well as their social development. So it is necessary to have robust instruments to provide a better understanding of these attitudes and preferences concerning teamwork. Such instruments also help to identify the factors that promote positive or negative attitudes within the context of group activities. Using a sample of 750 first and second year university students studying a degree in Kindergarten, Primary and Social Education, an instrument measuring attitudes toward team learning has been developed. Two distinct factors were obtained through various factorial analyses and structural equations: Academic attitudes and Social and emotional attitudes. Our study reveals that the instrument is both valid and reliable. Its application is both simple and fast and it has important implications for planning teaching and learning activities that contribute to an improvement in attitudes as well as the practice of teaching in the context of learning through teamwork. PMID:28676775

  16. Prediction of future falls in a community dwelling older adult population using instrumented balance and gait analysis.

    PubMed

    Bauer, C M; Gröger, I; Rupprecht, R; Marcar, V L; Gaßmann, K G

    2016-04-01

    The role of instrumented balance and gait assessment when screening for prospective fallers is currently a topic of controversial discussion. This study analyzed the association between variables derived from static posturography, instrumented gait analysis and clinical assessments with the occurrence of prospective falls in a sample of community dwelling older people. In this study 84 older people were analyzed. Based on a prospective occurrence of falls, participants were categorized into fallers and non-fallers. Variables derived from clinical assessments, static posturography and instrumented gait analysis were evaluated with respect to the association with the occurrence of prospective falls using a forward stepwise, binary, logistic regression procedure. Fallers displayed a significantly shorter single support time during walking while counting backwards, increased mediolateral to anteroposterior sway amplitude ratio, increased fast mediolateral oscillations and a larger coefficient (Coeff) of sway direction during various static posturography tests. Previous falls were insignificantly associated with the occurrence of prospective falls. Variables derived from posturography and instrumented gait analysis showed significant associations with the occurrence of prospective falls in a sample of community dwelling older adults.

  17. Intermittent fasting: A “new” historical strategy for controlling seizures?

    PubMed Central

    Hartman, Adam L.; Rubenstein, James E.; Kossoff, Eric H.

    2013-01-01

    Summary In antiquity, fasting was a treatment for epilepsy and a rationale for the ketogenic diet (KD). Preclinical data indicate the KD and intermittent fasting do not share identical anticonvulsant mechanisms. We implemented an intermittent fasting regimen in six children with an incomplete response to a KD. Three patients adhered to the combined intermittent fasting/KD regimen for 2 months and four had transient improvement in seizure control, albeit with some hunger-related adverse reactions. PMID:23206889

  18. Plasma FGF21 concentrations, adipose fibroblast growth factor receptor-1 and β-klotho expression decrease with fasting in northern elephant seals.

    PubMed

    Suzuki, Miwa; Lee, Andrew Y; Vázquez-Medina, José Pablo; Viscarra, Jose A; Crocker, Daniel E; Ortiz, Rudy M

    2015-05-15

    Fibroblast growth factor (FGF)-21 is secreted from the liver, pancreas, and adipose in response to prolonged fasting/starvation to facilitate lipid and glucose metabolism. Northern elephant seals naturally fast for several months, maintaining a relatively elevated metabolic rate to satisfy their energetic requirements. Thus, to better understand the impact of prolonged food deprivation on FGF21-associated changes, we analyzed the expression of FGF21, FGF receptor-1 (FGFR1), β-klotho (KLB; a co-activator of FGFR) in adipose, and plasma FGF21, glucose and 3-hydroxybutyrate in fasted elephant seal pups. Expression of FGFR1 and KLB mRNA decreased 98% and 43%, respectively, with fasting duration. While the 80% decrease in mean adipose FGF21 mRNA expression with fasting did not reach statistical significance, it paralleled the 39% decrease in plasma FGF21 concentrations suggesting that FGF21 is suppressed with fasting in elephant seals. Data demonstrate an atypical response of FGF21 to prolonged fasting in a mammal suggesting that FGF21-mediated mechanisms have evolved differentially in elephant seals. Furthermore, the typical fasting-induced, FGF21-mediated actions such as the inhibition of lipolysis in adipose may not be required in elephant seals as part of a naturally adapted mechanism to support their unique metabolic demands during prolonged fasting. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Plasma FGF21 Concentrations, Adipose Fibroblast Growth Factor Receptor-1 and β-Klotho Expression Decrease with Fasting in Northern Elephant Seals

    PubMed Central

    Suzuki, Miwa; Lee, Andrew; Vázquez-Medina, Jose Pablo; Viscarra, Jose A.; Crocker, Daniel E.; Ortiz, Rudy M.

    2015-01-01

    Fibroblast growth factor (FGF)-21 is secreted from the liver, pancreas, and adipose in response to prolonged fasting/starvation to facilitate lipid and glucose metabolism. Northern elephant seals naturally fast for several months, maintaining a relatively elevated metabolic rate to satisfy their energetic requirements. Thus, to better understand the impact of prolonged food deprivation on FGF21-associated changes, we analyzed the expression of FGF21, FGF receptor-1 (FGFR1), β-klotho (KLB; a co-activator of FGFR) in adipose, and plasma FGF21, glucose and 3-hydroxybutyrate in fasted elephant seal pups. Expression of FGFR1 and KLB mRNA decreased 98% and 43%, respectively, with fasting duration. While the 80% decrease in mean adipose FGF21 mRNA expression with fasting did not reach statistical significance, it paralleled the 39% decrease in plasma FGF21 concentrations suggesting that FGF21 is suppressed with fasting in elephant seals. Data demonstrate an atypical response of FGF21 to prolonged fasting in a mammal suggesting that FGF21-mediated mechanisms have evolved differentially in elephant seals. Furthermore, the typical fasting-induced, FGF21-mediated actions such as the inhibition of lipolysis in adipose may not be required in elephant seals as part of a naturally adapted mechanism to support their unique metabolic demands during prolonged fasting. PMID:25857751

  20. Elemental and charge state composition of the fast solar wind observed with SMS instruments on WIND

    NASA Technical Reports Server (NTRS)

    Gloeckler, G.; Galvin, A. B.; Ipavich, F. M.; Hamilton, D. C.; Bochsler, P.; Geiss, J.; Fisk, L. A.; Wilken, B.

    1995-01-01

    The elemental composition and charge state distributions of heavy ions of the solar wind provide essential information about: (1) atom-ion separation processes in the solar atmosphere leading to the 'FIP effect' (the overabundance of low First Ionization potential (FIP) elements in the solar wind compared to the photosphere); and (2) coronal temperature profiles, as well as mechanisms which heat the corona and accelerate the solar wind. This information is required for solar wind acceleration models. The SWICS instrument on Ulysses measures for all solar wind flow conditions the relative abundance of about 8 elements and 20 charge states of the solar wind. Furthermore, the Ulysses high-latitude orbit provides an unprecedented look at the solar wind from the polar coronal holes near solar minimum conditions. The MASS instrument on the WIND spacecraft is a high-mass resolution solar wind ion mass spectrometer that will provide routinely not only the abundances and charge state of all elements easily measured with SWICS, but also of N, Mg, S. The MASS sensor was fully operational at the end of 1994 and has sampled the in-ecliptic solar wind composition in both the slow and the corotating fast streams. This unique combination of SWICS on Ulysses and MASS on WIND allows us to view for the first time the solar wind from two regions of the large coronal hole. Observations with SWICS in the coronal hole wind: (1) indicate that the FIP effect is small; and (2) allow us determine the altitude of the maximum in the electron temperature profile, and indicate a maximum temperature of approximately 1.5 MK. New results from the SMS instruments on Wind will be compared with results from SWICS on Ulysses.

  1. Quality gap of educational services in viewpoints of students in Hormozgan University of medical sciences.

    PubMed

    Aghamolaei, Teamur; Zare, Shahram

    2008-06-18

    Higher education is growing fast and every day it becomes more and more exposed to globalization processes. The aim of this study was to determine the quality gap of educational services by using a modified SERVQUAL instrument among students in Hormozgan University of Medical Sciences. A cross-sectional study was carried out at Hormozgan University of Medical Sciences in 2007. In this study, a total of 300 students were selected randomly and asked to complete a questionnaire that was designed according to SERVQUAL methods. This questionnaire measured students' perceptions and expectations in five dimensions of service that consists of assurance, responsiveness, empathy, reliability and tangibles. The quality gap of educational services was determined based on differences between students' perceptions and expectations. The results demonstrated that in each of the five SERVQUAL dimensions, there was a negative quality gap. The least and the most negative quality gap means were in the reliability (-0.71) and responsiveness (-1.14) dimensions respectively. Also, there were significant differences between perceptions and expectations of students in all of the five SERVQUAL dimensions (p < 0.001). Negative quality gaps mean students' expectations exceed their perceptions. Thus, improvements are needed across all five dimensions.

  2. A novel avalanche-confinement TEPC for microdosimetry at nanometric level

    NASA Astrophysics Data System (ADS)

    Bortot, D.; Agosteo, S.; Colautti, P.; Conte, V.; Introini, M. V.; Lorenzoli, M.; Pasquato, S.; Pola, A.

    2017-09-01

    The tissue equivalent proportional counter (TEPC) is the most accurate device for measuring the microdosimetric properties of a particle beam, showing to properly assess the relative biological effectiveness by linking the physical parameters of the radiation with the corresponding biological response. Nevertheless no detailed information on the track structure of the impinging particles can be obtained, since the lower operation limit of the common TEPCs is about 0.3 ?m. On the other hand, the pattern of particle interactions at the nanometer level, which demonstrated to have a strong correlation with radiation-induced damages to the DNA, is directly measured by only three different nanodosimeters worldwide: practical instruments are not yet available. The gap between microdosimetry and track-nanodosimetry can be filled partially by extending the TEPC response down to the nanometric region. A feasibility study of a novel TEPC designed to simulate biological sites in the nanometric domain was performed. The present paper aims at describing the design, the development and the characterization of this avalanche-confinement TEPC. Irradiations with photons, fast neutrons and low-energy carbon ions demonstrated the capability of this TEPC of measuring in the range 0.3 μm - 25 nm.

  3. Clinical determination of glucose in human serum by a tomato skin biosensor.

    PubMed

    Han, Hui; Li, Yi; Yue, Huan; Zhou, Zaide; Xiao, Dan; Choi, Martin M F

    2008-09-01

    Glucose biosensors based on enzyme reaction of glucose oxidase were studied because the symptomatic therapy of diabetes mellitus requires reliable assessment of blood glucose level at frequent intervals. Tomato skin membranes have been successfully employed to entrap glucose oxidase for fabrication of glucose biosensor. Glucose oxidase was immobilized onto the tomato skin and the enzyme membrane was then positioned on the surface of an oxygen electrode. The glucose concentration was quantified by the change of dissolved oxygen. All the serum samples were also simultaneously determined by a Hitachi 7060 chemistry analyzer. The response of the biosensor showed a linear relationship with a concentration range of 1.0-30.0 mmol/l glucose. The limit of detection was 0.20 mmol/l. Error Grid analysis demonstrated that 100% of the results fell within clinically acceptable zones A and B. The F- and t-tests showed no significant differences between the 2 methods. The recovery was 95.0-110.0% for 30 serum samples analysis. The tomato skin biosensor possesses the advantages of simple fabrication, fast response time, low cost and high sensitivity. The results of our method are more accurate than and match well with the current clinical instrument method.

  4. Neutron temporal diagnostic for high-yield deuterium-tritium cryogenic implosions on OMEGA

    DOE PAGES

    Stoeckl, C.; Boni, R.; Ehrne, F.; ...

    2016-05-10

    A next-generation neutron temporal diagnostic (NTD) capable of recording high-quality data for the highest anticipated yield cryogenic DT implosion experiments was recently installed at the Omega Laser Facility. A high-quality measurement of the neutron production width is required to determine the hot-spot pressure achieved in inertial confinement fusion experiments—a key metric in assessing the quality of these implosions. The design of this NTD is based on a fast-rise-time plastic scintillator, which converts the neutron kinetic energy to 350- to 450-nm-wavelength light. The light from the scintillator inside the nose-cone assembly is relayed ~16 m to a streak camera in amore » well-shielded location. An ~200× reduction in neutron background was observed during the first high-yield DT cryogenic implosions compared to the current NTD installation on OMEGA. An impulse response of ~40±10 ps was measured in a dedicated experiment using hard x rays from a planar target irradiated with a 10-ps short pulse from the OMEGA EP laser. Furthermore, the measured instrument response includes contributions from the scintillator rise time, optical relay, and streak camera.« less

  5. Neutron temporal diagnostic for high-yield deuterium–tritium cryogenic implosions on OMEGA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stoeckl, C.; Boni, R.; Ehrne, F.

    A next-generation neutron temporal diagnostic (NTD) capable of recording high-quality data for the highest anticipated yield cryogenic deuterium–tritium (DT) implosion experiments was recently installed at the Omega Laser Facility. A high-quality measurement of the neutron production width is required to determine the hot-spot pressure achieved in inertial confinement fusion experiments—a key metric in assessing the quality of these implosions. The design of this NTD is based on a fast-rise-time plastic scintillator, which converts the neutron kinetic energy to 350- to 450-nm-wavelength light. The light from the scintillator inside the nose-cone assembly is relayed ∼16 m to a streak camera inmore » a well-shielded location. An ∼200× reduction in neutron background was observed during the first high-yield DT cryogenic implosions compared to the current NTD installation on OMEGA. An impulse response of ∼40 ± 10 ps was measured in a dedicated experiment using hard x-rays from a planar target irradiated with a 10-ps short pulse from the OMEGA EP laser. The measured instrument response includes contributions from the scintillator rise time, optical relay, and streak camera.« less

  6. Neutron temporal diagnostic for high-yield deuterium-tritium cryogenic implosions on OMEGA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stoeckl, C.; Boni, R.; Ehrne, F.

    A next-generation neutron temporal diagnostic (NTD) capable of recording high-quality data for the highest anticipated yield cryogenic DT implosion experiments was recently installed at the Omega Laser Facility. A high-quality measurement of the neutron production width is required to determine the hot-spot pressure achieved in inertial confinement fusion experiments—a key metric in assessing the quality of these implosions. The design of this NTD is based on a fast-rise-time plastic scintillator, which converts the neutron kinetic energy to 350- to 450-nm-wavelength light. The light from the scintillator inside the nose-cone assembly is relayed ~16 m to a streak camera in amore » well-shielded location. An ~200× reduction in neutron background was observed during the first high-yield DT cryogenic implosions compared to the current NTD installation on OMEGA. An impulse response of ~40±10 ps was measured in a dedicated experiment using hard x rays from a planar target irradiated with a 10-ps short pulse from the OMEGA EP laser. Furthermore, the measured instrument response includes contributions from the scintillator rise time, optical relay, and streak camera.« less

  7. Modeling of fast neutral-beam-generated ion effects on MHD-spectroscopic observations of resistive wall mode stability in DIII-D plasmas [Modeling of fast neutral-beam-generated ion effects on MHD spectroscopic observations of RWM stability in DIII-D plasmas

    DOE PAGES

    Turco, Francesca; Turnbull, Alan D.; Hanson, Jeremy M.; ...

    2015-02-03

    Experiments conducted at DIII-D investigate the role of drift kinetic damping and fast neutral beam injection (NBI)-ions in the approach to the no-wall β N limit. Modelling results show that the drift kinetic effects are significant and necessary to reproduce the measured plasma response at the ideal no-wall limit. Fast neutral-beam ions and rotation play important roles and are crucial to quantitatively match the experiment. In this paper, we report on the model validation of a series of plasmas with increasing β N, where the plasma stability is probed by active magnetohydrodynamic (MHD) spectroscopy. The response of the plasma tomore » an externally applied field is used to probe the stable side of the resistive wall mode and obtain an indication of the proximity of the equilibrium to an instability limit. We describe the comparison between the measured plasma response and that calculated by means of the drift kinetic MARS-K code, which includes the toroidal rotation, the electron and ion drift-kinetic resonances, and the presence of fast particles for the modelled plasmas. The inclusion of kinetic effects allows the code to reproduce the experimental results within ~13% for both the amplitude and phase of the plasma response, which is a significant improvement with respect to the undamped MHD-only model. The presence of fast NBI-generated ions is necessary to obtain the low response at the highest β N levels (~90% of the ideal no-wall limit). Finally, the toroidal rotation has an impact on the results, and a sensitivity study shows that a large variation in the predicted response is caused by the details of the rotation profiles at high β N.« less

  8. CRiSP: An Instrument for Assessing Student Perceptions of Classroom Response Systems

    ERIC Educational Resources Information Center

    Richardson, Alice M.; Dunn, Peter K.; McDonald, Christine; Oprescu, Florin

    2015-01-01

    This paper describes the development and validation of an instrument for evaluating classroom response systems (CRS). While a number of studies evaluating CRS have been published to date, no standardised instrument exists as a means of evaluating the impact of using the CRS. This means that comparing the different systems, or evaluating the…

  9. Finger Forces in Clarinet Playing

    PubMed Central

    Hofmann, Alex; Goebl, Werner

    2016-01-01

    Clarinettists close and open multiple tone holes to alter the pitch of the tones. Their fingering technique must be fast, precise, and coordinated with the tongue articulation. In this empirical study, finger force profiles and tongue techniques of clarinet students (N = 17) and professional clarinettists (N = 6) were investigated under controlled performance conditions. First, in an expressive-performance task, eight selected excerpts from the first Weber Concerto were performed. These excerpts were chosen to fit in a 2 × 2 × 2 design (register: low–high; tempo: slow–fast, dynamics: soft–loud). There was an additional condition controlled by the experimenter, which determined the expression levels (low–high) of the performers. Second, a technical-exercise task, an isochronous 23-tone melody was designed that required different effectors to produce the sequence (finger-only, tongue-only, combined tongue-finger actions). The melody was performed in three tempo conditions (slow, medium, fast) in a synchronization-continuation paradigm. Participants played on a sensor-equipped Viennese clarinet, which tracked finger forces and reed oscillations simultaneously. From the data, average finger force (Fmean) and peak force (Fmax) were calculated. The overall finger forces were low (Fmean = 1.17 N, Fmax = 3.05 N) compared to those on other musical instruments (e.g., guitar). Participants applied the largest finger forces during the high expression level performance conditions (Fmean = 1.21 N). For the technical exercise task, timing and articulation information were extracted from the reed signal. Here, the timing precision of the fingers deteriorated the timing precision of the tongue for combined tongue-finger actions, especially for faster tempi. Although individual finger force profiles were overlapping, the group of professional players applied less finger force overall (Fmean = 0.54 N). Such sensor instruments provide useful insights into player-instrument interactions and can also be used in the future to give feedback to students in various learning and practising situations. PMID:27540367

  10. Training and Validation of the Fast PCRTM_Solar Model

    NASA Astrophysics Data System (ADS)

    Yang, Q.; Liu, X.; Wu, W.; Yang, P.; Wang, C.

    2015-12-01

    Fast and accurate radiative transfer model is the key for satellite data assimilation for remote sensing application. The simulation of the satellite remote sensing radiances is very complicated since many physical processes, such as absorption, emission, and scattering, are involved due to the interactions between electromagnetic radiation and earth surface, water vapor, clouds, aerosols, and gas molecules in the sky. The principal component-based radiative transfer model (PCRTM) has been developed for various passive IR and MW instruments. In this work, we extended PCRTM to including the contribution from solar radiation. The cloud/aerosol bidirectional reflectances have been carefully calculated using the well-known Discrete-Ordinate-Method Radiative Transfer (DISORT) model under over 10 millions of diverse conditions with varying cloud particle size, wavelength, satellite viewing direction, and solar angles. The obtained results were compressed significantly using principal component analysis and used in the mono domain radiance calculation. We used 1352 different atmosphere profiles, each of them has different surface skin temperatures and surface pressures in our training. Different surface emissivity spectra were derived from ASTER database and emissivity models. Some artificially generated emissivity spectra were also used to account for diverse surface types of the earth. Concentrations of sixteen trace gases were varied systematically in the training and the remaining trace gas contributions were accounted for as a fixed gas. Training was done in both clear and cloudy skies conditions. Finally the nonlocal thermal equilibrium (NLTE) induced radiance change was included for daytime conditions. We have updated the PCRTM model for instruments such as IASI, NASTI, CrIS, AIRS, and SHIS. The training results show that the PCRTM model can calculate thousands of channel radiances by computing only a few hundreds of mono radiances. This greatly increased the computation efficiency since we do not need to calculate the millions of mono radiances and do the convolution process. The results from fast PCRTM_Solar simulation were compared to the instrument observed data. The simulated results were excellently agreed with the observations.

  11. Chemometric aided NIR portable instrument for rapid assessment of medicine quality.

    PubMed

    Zontov, Y V; Balyklova, K S; Titova, A V; Rodionova, O Ye; Pomerantsev, A L

    2016-11-30

    The progress in instrumentation technology has led to miniaturization of NIR instruments. Fast systems that contain no moving parts were developed to be used in the field, warehouses, drugstores, etc. At the same time, in general these portable/handheld spectrometers have a lower spectral resolution and a narrower spectral region than stationary ones. Vendors of portable instruments supply their equipment with special software for spectra processing, which aims at simplifying the analyst's work to the highest degree possible. Often such software is not fully capable of solving complex problems. In application to a real-world problem of counterfeit drug detection we demonstrate that even impaired spectral data do carry information sufficient for drug authentication. The chemometrics aided approach helps to extract this information and thus to extend the applicability of miniaturized NIR instruments. MicroPhazir-RX NIR spectrometer is used as an example of a portable instrument. The data driven soft independent modeling of class analogy (DD-SIMCA) method is employed for data processing. A representative set of tablets of a calcium channel blocker from 6 different manufacturers is used to illustrate the proposed approach. It is shown that the DD-SIMCA approach yields a better result than the basic method provided by the instrument vendor. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. A surface ice module for wind turbine dynamic response simulation using FAST

    DOE PAGES

    Yu, Bingbin; Karr, Dale G.; Song, Huimin; ...

    2016-06-03

    It is a fact that developing offshore wind energy has become more and more serious worldwide in recent years. Many of the promising offshore wind farm locations are in cold regions that may have ice cover during wintertime. The challenge of possible ice loads on offshore wind turbines raises the demand of modeling capacity of dynamic wind turbine response under the joint action of ice, wind, wave, and current. The simulation software FAST is an open source computer-aided engineering (CAE) package maintained by the National Renewable Energy Laboratory. In this paper, a new module of FAST for assessing the dynamicmore » response of offshore wind turbines subjected to ice forcing is presented. In the ice module, several models are presented which involve both prescribed forcing and coupled response. For conditions in which the ice forcing is essentially decoupled from the structural response, ice forces are established from existing models for brittle and ductile ice failure. For conditions in which the ice failure and the structural response are coupled, such as lock-in conditions, a rate-dependent ice model is described, which is developed in conjunction with a new modularization framework for FAST. In this paper, analytical ice mechanics models are presented that incorporate ice floe forcing, deformation, and failure. For lower speeds, forces slowly build until the ice strength is reached and ice fails resulting in a quasi-static condition. For intermediate speeds, the ice failure can be coupled with the structural response and resulting in coinciding periods of the ice failure and the structural response. A third regime occurs at high speeds of encounter in which brittle fracturing of the ice feature occurs in a random pattern, which results in a random vibration excitation of the structure. An example wind turbine response is simulated under ice loading of each of the presented models. This module adds to FAST the capabilities for analyzing the response of wind turbines subjected to forces resulting from ice impact on the turbine support structure. The conditions considered in this module are specifically addressed in the International Organization for Standardization (ISO) standard 19906:2010 for arctic offshore structures design consideration. Special consideration of lock-in vibrations is required due to the detrimental effects of such response with regard to fatigue and foundation/soil response. Finally, the use of FAST for transient, time domain simulation with the new ice module is well suited for such analyses.« less

  13. The InSight Mission's Martian Atmospheric Science Goals, Capabilities and Instrumentation

    NASA Astrophysics Data System (ADS)

    Smrekar, S. E.; Banfield, D. J.

    2015-12-01

    The InSight Mission to Mars will launch in March 2016 and land in September 2016, beginning at least 1 Mars year of observations from the surface of Mars. The primary scientific goal of the InSight mission is to characterize the interior of Mars (both deep and near-surface), but it is also equipped with very capable meteorological instrumentation, and consequently has atmospheric science goals as well. The instrumentation InSight carries includes a very sensitive and fast response pressure sensor, as well as a pair of wind and temperature sensors that are similar to those flown on MSL and will be on Mars2020. These sensors will operate essentially continuously at Mars, a first; enabling the production of a complete sampling of the Martian environment, including short-lived transients. InSight also carries cameras that can be used to survey not only the ground in the near environment, but also sky conditions. The pressure sensor responds to signals below 10Hz (~10X its predecessors) and has a noise level of about 10 mPa (better than 1/10 its predecessors). The pair of wind and temperature sensors have been carefully placed opposite one another on the deck to minimize lander interference as much as possible, leaving one sensor on the windward side of the lander at any time. These capabilities, combined with their continuous sampling enable us to pursue new atmospheric science questions at Mars, including quantifying thresholds for aeolian change, detailed dust devil characterization, bolide infrasonic detection and characterization, and quantifying secular trends in pressure. This is in addition to characterizing the normal meteorology at the InSight landing site, which while not completely new, will provide incremental and important constraints for Martian Atmospheric models. We also expect there to be unexpected discoveries, as well as more synergistic approaches to coordination among all the instruments on InSight that may result even more novel capabilities.

  14. Performance of the Digital Science Partnership Remotely-Operated 0.5-Meter Corrected Dall-Kirkham Telescopes

    NASA Astrophysics Data System (ADS)

    Kielkopf, John F.; Carter, B.; Brown, C.; Hart, R.; Hay, J.; Waite, I.

    2007-12-01

    The Digital Science Partnership, a collaboration of the University of Louisville and the University of Southern Queensland, operates a pair of 0.5-meter telescopes for teaching, research, and informal education. The instruments were installed at sites near Toowoomba, Australia, and Louisville, Kentucky in 2006. The Planewave Instruments optical systems employ a unique Dall-Kirkham design incorporating a two-element corrector that demagnifies the image, flattens the focal plane, and reduces coma. These instruments have a moderately fast f/6.8 focal ratio and maintain image quality with little vignetting over a field 42 mm in diameter (0.7 degree). With a 9-micron pixel CCD such as the KAF-6303E, the image scale of 0.55 seconds of arc per pixel typically yields seeing-limited image quality at our sites. The telescopes and their enclosure are operated in a live remote observing mode through Linux-based software, including a dome-control system that uses RFID tags for absolute rotation encoding. After several months of testing and development we have examples of images and photometry from both sites that illustrate the performance of the system. We will discuss image quality, as well as practical matters such as pointing accuracy and field acquisition, auto-guiding, communication latency in large file transfer, and our experience with remote observing assisted by teleconferencing. Time-delay-integration (TDI) imaging, in which the telescope is stationary while the CCD is clocked to track in right ascension, is under study. The technique offers wide fields of view with very high signal-to-noise ratio, and can be implemented in robotically operated instruments used in monitoring, rapid-response, and educational programs. Results for conventional and TDI imaging from the dark site in Australia compared to the brighter suburban site in Kentucky show the benefits of access to dark sites through international partnerships that remote operation technology offers.

  15. The effect of a 48 h fast on the thermoregulatory responses to graded cooling in man.

    PubMed

    Macdonald, I A; Bennett, T; Sainsbury, R

    1984-10-01

    The thermoregulatory responses to graded cooling were measured in 11 healthy male subjects after a 12 h fast and after a 48 h fast. The cooling stimulus was produced by changing the temperature of the skin of the trunk and legs with a water-perfused suit. Five levels of skin temperature from 35.5 to 24 degrees C were applied on each occasion. After a 12 h fast, core temperature was maintained during cooling. This maintenance of core temperature was associated with an increase in metabolic rate and a reduction in blood flow to the hand and to the forearm. After 48 h of fasting, the subjects could not maintain core temperature during cooling, and a decrease of 0.36 +/- 0.05 degrees C occurred as the suit temperature was reduced from 35.9 to 24 degrees C. Metabolic rate was slightly higher after the 48 h fast than after the 12 h fast, but similar increases in metabolic rate were observed during cooling. Vasoconstriction in the hand was initially less after a 48 h fast than after a 12 h fast, but at the lowest suit temperature, hand blood flow was similar, and low, on both occasions. After 48 h of fasting, forearm blood flow was elevated at all suit temperatures, being approximately twice the level recorded after the 12 h fast. Venous plasma noradrenaline levels did not change during cooling after the 12 h fast, whilst after 48 h of fasting a significant increase in noradrenaline level was observed at the lowest suit temperature. The results of this study provide further evidence that fasting induces an impairment of autonomic reflex mechanisms, but it is not clear whether this is due to a suppression of sympathetic nervous activity.

  16. Triggering Avoidance: Dissociable Influences of Aversive Pavlovian Conditioned Stimuli on Human Instrumental Behavior.

    PubMed

    Garofalo, Sara; Robbins, Trevor W

    2017-01-01

    The present study investigates human aversive Pavlovian-to-Instrumental Transfer (PIT) and possible influences of outcome devaluation and instrumental overtraining on this effect. PIT measures the extent to which a Pavlovian conditioned stimulus (CS) can increase instrumental responses independently paired with the same (outcome-specific transfer) or a different (general transfer) reinforcer. Two measures of PIT were obtained: the percentage of instrumental responses and the vigor of such responses. Thirty-eight volunteers performed a standard PIT task sequence. Results showed a double dissociation between outcome-specific and general transfer: the first selectively expressed in the amount of responses, the second in the vigor measure solely. Furthermore, outcome-specific transfer was enhanced by overtraining, but not affected by devaluation. General transfer, on the other hand, was affected by neither overtraining, nor devaluation. A positive correlation between general transfer and sensitivity to punishments was found. Findings are discussed in terms of hypothetically different underlying neurobehavioral mechanisms and their relations to habits and goal-directed behavior.

  17. The influence of feeding and fasting on plasma metabolites in the dogfish shark (Squalus acanthias).

    PubMed

    Wood, Chris M; Walsh, Patrick J; Kajimura, Makiko; McClelland, Grant B; Chew, Shit F

    2010-04-01

    Dogfish sharks are opportunistic predators, eating large meals at irregular intervals. Here we present a synthesis of data from several previous studies on responses in plasma metabolites after natural feeding and during prolonged fasting (up to 56days), together with new data on changes in plasma concentrations of amino acids and non-esterified fatty acids. Post-prandial and long-term fasting responses were compared to control sharks fasted for 7days, a typical inter-meal interval. A feeding frenzy was created in which dogfish were allowed to feed naturally on dead teleosts at two consumed ration levels, 2.6% and 5.5% of body weight. Most responses were more pronounced at the higher ration level. These included increases in urea and TMAO concentrations at 20h, followed by stability through to 56days of fasting. Ammonia levels were low and exhibited little short-term response to feeding, but declined to very low values during the extended fast. Glucose and beta-hydroxybutyrate both fell after feeding, the latter to a greater and more prolonged extent (up to 60h), whereas acetoacetate did not change. During prolonged fasting, glucose concentrations were well regulated, but beta-hydroxybutyrate increased to 2-3-fold control levels. Total plasma amino acid concentrations increased in a biphasic fashion, with peaks at 6-20h, and 48-60h after the meal, followed by homeostasis during the extended fast. Essential and non-essential amino acids generally followed this same pattern, though some exhibited different trends after feeding: taurine, beta-alanine, and glycine (decreases or stability), alanine and glutamine (modest prolonged increases), and threonine, serine, asparagine, and valine (much larger short-term increases). Plasma non-esterified fatty acid concentrations declined markedly through 48h after the 2.6% meal. These data are interpreted in light of companion studies showing elevations in aerobic metabolic rate, urea production, rectal gland function, metabolic base excretion, and activation of ornithine-urea cycle and aerobic enzymes after the meal, and muscle N-depletion but maintenance of osmolality and urea production during long-term fasting.

  18. Is fast fiber innervation responsible for increased acetylcholinesterase activity in reinnervating soleus muscles?

    NASA Technical Reports Server (NTRS)

    Misulis, K. E.; Dettbarn, W. D.

    1985-01-01

    An investigation was conducted as to whether the predominantly slow SOL, which is low in AChE activity, is initially reinnervated by axons that originally innervated fast muscle fibers with high AChE activity, such as those of the EDL. Local denervation of the SOL in the guinea pig was performed because this muscle is composed solely of slow (type I) fibers; thereby virtually eliminating the possibility of homologous muscle fast fiber innervation. The overshoot in this preparation was qualitatively similar to that seen with distal denervation in the guinea pig and local and distal denervation in the rat. Thus, initial fast fiber innvervation is not responsible for the patterns of change in AChE activity seen with reinnervation in the SOL. It is concluded that the neural control of AChe is different in these two muscles and may reflect specific differences in the characteristics of AChE regulation in fast and slow muscle.

  19. Extinction and the associative structure of heterogeneous instrumental chains.

    PubMed

    Thrailkill, Eric A; Bouton, Mark E

    2016-09-01

    Drug abuse, overeating, and smoking are all examples of instrumental behaviors that often involve chains or sequences of behavior. A behavior chain is minimally composed of a procurement response that is required in order for a subsequent consumption response to be reinforced. Despite the translational importance of behavior chains, few studies have attempted to understand what binds them together and takes them apart. This article surveys the development of the heterogeneous instrumental chain method and introduces recent findings that have used extinction to analyze the associative content of (what is learned in) the chain. Chained responses that are occasion-set by their own discriminative stimuli may be directly associated; extinction of the procurement response weakens its associated consumption response, and extinction of the consumption response weakens its associated procurement response. Extinction itself involves learning to inhibit the response. Extinguished chained responses are subject to renewal when they are tested either back in the acquisition context or in a new context. In addition, a consumption response that is extinguished outside its chain is renewed when returned to the context of the preceding response in the chain. Research on heterogeneous behavior chains can provide important insights into an important but often overlooked aspect of instrumental learning. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Lithium-containing scintillators for thermal neutron, fast neutron, and gamma detection

    DOEpatents

    Zaitseva, Natalia P.; Carman, M. Leslie; Faust, Michelle A.

    2016-03-01

    In one embodiment, a scintillator includes a scintillator material; a primary fluor, and a Li-containing compound, where the Li-containing compound is soluble in the primary fluor, and where the scintillator exhibits an optical response signature for thermal neutrons that is different than an optical response signature for fast neutrons and gamma rays.

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