Science.gov

Sample records for accurate real-time measurement

  1. A Measure of Real-Time Intelligence

    NASA Astrophysics Data System (ADS)

    Gavane, Vaibhav

    2013-03-01

    We propose a new measure of intelligence for general reinforcement learning agents, based on the notion that an agent's environment can change at any step of execution of the agent. That is, an agent is considered to be interacting with its environment in real-time. In this sense, the resulting intelligence measure is more general than the universal intelligence measure (Legg and Hutter, 2007) and the anytime universal intelligence test (Hernández-Orallo and Dowe, 2010). A major advantage of the measure is that an agent's computational complexity is factored into the measure in a natural manner. We show that there exist agents with intelligence arbitrarily close to the theoretical maximum, and that the intelligence of agents depends on their parallel processing capability. We thus believe that the measure can provide a better evaluation of agents and guidance for building practical agents with high intelligence.

  2. Real-time structured light intraoral 3D measurement pipeline

    NASA Astrophysics Data System (ADS)

    Gheorghe, Radu; Tchouprakov, Andrei; Sokolov, Roman

    2013-02-01

    Computer aided design and manufacturing (CAD/CAM) is increasingly becoming a standard feature and service provided to patients in dentist offices and denture manufacturing laboratories. Although the quality of the tools and data has slowly improved in the last years, due to various surface measurement challenges, practical, accurate, invivo, real-time 3D high quality data acquisition and processing still needs improving. Advances in GPU computational power have allowed for achieving near real-time 3D intraoral in-vivo scanning of patient's teeth. We explore in this paper, from a real-time perspective, a hardware-software-GPU solution that addresses all the requirements mentioned before. Moreover we exemplify and quantify the hard and soft deadlines required by such a system and illustrate how they are supported in our implementation.

  3. Kinetic Measurement and Real Time Visualization of Somatic Reprogramming.

    PubMed

    Quintanilla, Rene H; Asprer, Joanna; Sylakowski, Kyle; Lakshmipathy, Uma

    2016-01-01

    Somatic reprogramming has enabled the conversion of adult cells to induced pluripotent stem cells (iPSC) from diverse genetic backgrounds and disease phenotypes. Recent advances have identified more efficient and safe methods for introduction of reprogramming factors. However, there are few tools to monitor and track the progression of reprogramming. Current methods for monitoring reprogramming rely on the qualitative inspection of morphology or staining with stem cell-specific dyes and antibodies. Tools to dissect the progression of iPSC generation can help better understand the process under different conditions from diverse cell sources. This study presents key approaches for kinetic measurement of reprogramming progression using flow cytometry as well as real-time monitoring via imaging. To measure the kinetics of reprogramming, flow analysis was performed at discrete time points using antibodies against positive and negative pluripotent stem cell markers. The combination of real-time visualization and flow analysis enables the quantitative study of reprogramming at different stages and provides a more accurate comparison of different systems and methods. Real-time, image-based analysis was used for the continuous monitoring of fibroblasts as they are reprogrammed in a feeder-free medium system. The kinetics of colony formation was measured based on confluence in the phase contrast or fluorescence channels after staining with live alkaline phosphatase dye or antibodies against SSEA4 or TRA-1-60. The results indicated that measurement of confluence provides semi-quantitative metrics to monitor the progression of reprogramming. PMID:27500543

  4. Severe storms measurement system real time data processing and displays

    NASA Technical Reports Server (NTRS)

    Jeffreys, H. B.

    1980-01-01

    The objectives of the system are to provide the system operator with real time system performance check and to provide data recording of all SSMS data. Meteorologists are provided with real time indication of meteorological data measurements including aid for directing flight profiles in real time and aid for directing SSMS operations. A day-to-day feedback is provided to meteorologists, system operators, and flight crews for flight planning on subsequent flight tests days.

  5. Superhilac real-time velocity measurements

    SciTech Connect

    Feinberg, B.; Meaney, D.; Thatcher, R.; Timossi, C.

    1987-03-01

    Phase probes have been placed in several external beam lines at the LBL heavy ion linear accelerator (SuperHILAC) to provide non-destructive velocity measurements independent of the ion being accelerated. The existing system has been improved to provide the following features: a display refresh rate better than twice per second, a sensitive pseudo-correlation technique to pick out the signal from the noise, simultaneous measurements of up to four ion velocities when more than one beam is being accelerated, and a touch-screen operator interface. These improvements allow the system to be used as a routine tuning aid and beam velocity monitor.

  6. Estimating correlation for a real-time measure of connectivity.

    PubMed

    Arunkumar, Akhil; Panday, Ashish; Joshi, Bharat; Ravindran, Arun; Zaveri, Hitten P

    2012-01-01

    There has recently been considerable interest in connectivity analysis of fMRI and scalp and intracranial EEG time-series. The computational requirements of the pair-wise correlation (PWC), the core time-series measure used to estimate connectivity, presents a challenge to the real-time estimation of the PWC between all pairs of multiple time-series. We describe a parallel algorithm for computing PWC in real-time for streaming data from multiple channels. The algorithm was implemented on the Intel Xeon™ and IBM Cell Broadband Engine™ platforms. We evaluated time to estimate correlation for signals recorded with different acquisition parameters as a comparison to real-time constraints. We demonstrate that the execution time of these efficient implementations meet real-time constraints in most instances. PMID:23367098

  7. Real-Time Measurement of Vehicle Exhaust Gas Flow

    SciTech Connect

    Hardy, J.E.; Hylton, J.O.; Joy, R.D.; McKnight, T.E.

    1999-06-28

    A flow measurement system was developed to measure, in real-time, the exhaust gas flow from vehicies. This new system was based on the vortex shedding principle using ultrasonic detectors for sensing the shed vortices. The flow meter was designed to measure flow over a range of 1 to 366 Ips with an inaccuracy of ~1o/0 of reading. Additionally, the meter was engineered to cause minimal pressure drop (less than 125mm of water), to function in a high temperature environment (up to 650oC) with thermal transients of 15 oC/s, and to have a response time of 0.1 seconds for a 10% to 90!40 step change. The flow meter was also configured to measure hi-directional flow. Several flow meter prototypes were fabricated, tested, and calibrated in air, simulated exhaust gas, and actual exhaust gas. Testing included gas temperatures to 600oC, step response experiments, and flow rates from O to 360 lps in air and exhaust gas. Two prototypes have been tested extensively at NIST and two additional meters have been installed in exhaust gas flow lines for over one year. This new flow meter design has shown to be accurate, durabIe, fast responding, and to have a wide rangeabi~ity.

  8. Real-time measurement of mental workload: A feasibility study

    NASA Technical Reports Server (NTRS)

    Kramer, Arthur; Humphrey, Darryl; Sirevaag, Erik; Mecklinger, Axel

    1990-01-01

    The primary goal of the study was to explore the utility of event-related brain potentials (ERP) as real-time measures of workload. To this end, subjects performed two different tasks both separately and together. One task required that subjects monitor a bank of constantly changing gauges and detect critical deviations. Difficulty was varied by changing the predictability of the gauges. The second task was mental arithmetic. Difficulty was varied by requiring subjects to perform operations on either two or three columns of numbers. Two conditions that could easily be distinguished on the basis of performance measures were selected for the real-time evaluation of ERPs. A bootstrapping approach was adopted in which one thousand samples of n trials (n = 1, 3, 5 ...65) were classified using several measures of P300 and Slow Wave amplitude. Classification accuracies of 85 percent were achieved with 25 trials. Results are discussed in terms of potential enhancements for real-time recording.

  9. An accurate assay for HCV based on real-time fluorescence detection of isothermal RNA amplification.

    PubMed

    Wu, Xuping; Wang, Jianfang; Song, Jinyun; Li, Jiayan; Yang, Yongfeng

    2016-09-01

    Hepatitis C virus (HCV) is one of the common reasons of liver fibrosis and hepatocellular carcinoma (HCC). Early, rapid and accurate HCV RNA detection is important to prevent and control liver disease. A simultaneous amplification and testing (SAT) assay, which is based on isothermal amplification of RNA and real-time fluorescence detection, was designed to optimize routine HCV RNA detection. In this study, HCV RNA and an internal control (IC) were amplified and analyzed simultaneously by SAT assay and detection of fluorescence using routine real-time PCR equipment. The assay detected as few as 10 copies of HCV RNA transcripts. We tested 705 serum samples with SAT, among which 96.4% (680/705) showed consistent results compared with routine real-time PCR. About 92% (23/25) discordant samples were confirmed to be same results as SAT-HCV by using a second real-time PCR. The sensitivity and specificity of SAT-HCV assay were 99.6% (461/463) and 100% (242/242), respectively. In conclusion, the SAT assay is an accurate test with a high specificity and sensitivity which may increase the detection rate of HCV. It is therefore a promising tool to diagnose HCV infection. PMID:27283884

  10. Real-time precision concentration measurement for flowing liquid solutions

    NASA Astrophysics Data System (ADS)

    Krishna, V.; Fan, C. H.; Longtin, J. P.

    2000-10-01

    The precise, real-time measurement of liquid concentration is important in fundamental research, chemical analysis, mixing processes, and manufacturing, e.g., in the food and semiconductor industries. This work presents a laser-based, noninvasive technique to measure concentration changes of flowing liquids in real time. The essential components in the system include a 5 mW laser diode coupled to a single-mode optical fiber, a triangular optical cell, and a high-resolution beam position sensor. The instrument provides a large range of concentration measurement, typically 0%-100% for binary liquid mixtures, while providing a resolution on the order of 0.05% concentration or better. The experimental configuration is small, reliable, and inexpensive. Results are presented for NaCl and MgCl2 aqueous solutions with concentrations ranging from 0% to 25%, with very good agreement found between measured and true concentrations.

  11. Rapid and Accurate Identification of Coagulase-Negative Staphylococci by Real-Time PCR

    PubMed Central

    Edwards, K. J.; Kaufmann, M. E.; Saunders, N. A.

    2001-01-01

    Biprobe identification assays based on real-time PCR were designed for 15 species of coagulase-negative staphylococci (CNS). Three sets of primers and four biprobes were designed from two variable regions of the 16S rRNA gene. An identification scheme was developed based on the pattern of melting peaks observed with the four biprobes that had been tested on 24 type strains. This scheme was then tested on 100 previously identified clinical isolates and 42 blindly tested isolates. For 125 of the 142 clinical isolates there was a perfect correlation between the biprobe identification and the result of the ID 32 Staph phenotypic tests and PCR. For 12 of the other isolates a 300-bp portion of the 16S rRNA gene was sequenced to determine identity. The remaining five isolates could not be fully identified. LightCycler real-time PCR allowed rapid and accurate identification of the important CNS implicated in infection. PMID:11526126

  12. Real-Time Dynamics Monitoring System with Synchronized Phasor Measurements

    2005-01-01

    The Real-Time Dynamics Monitoring System is designed to monitor the dynamics within the power grid and assess the system behavior during normal and disturbance conditions. The RTDMS application was built on the Grid-3P technology platform and takes real-time information collected by Synchronized Phasor Measurement Units (PMU5) or other collection devices and transmitted to a central Phasor Data Concentrator (PDC) for monitoring grid dynamics. The data is sampled 30 times per second and is time-synchronized. Thismore » data is processed to create graphical and geographical displays to provide visualization for frequency/frequency response, voltage magnitudes and angles, voltage angle differences across critical paths as well as real and reactive power-flows on a sub-second and second basis. Software allows for monitoring, tracking, historical data archiving and electric system troubleshooting for reliability management.« less

  13. Continuous real-time measurement of aqueous cyanide

    DOEpatents

    Rosentreter, Jeffrey J.; Gering, Kevin L.

    2007-03-06

    This invention provides a method and system capable of the continuous, real-time measurement of low concentrations of aqueous free cyanide (CN) using an on-line, flow through system. The system is based on the selective reactivity of cyanide anions and the characteristically nonreactive nature of metallic gold films, wherein this selective reactivity is exploited as an indirect measurement for aqueous cyanide. In the present invention the dissolution of gold, due to the solubilization reaction with the analyte cyanide anion, is monitored using a piezoelectric microbalance contained within a flow cell.

  14. Real-time estimation of ionospheric delay using GPS measurements

    NASA Astrophysics Data System (ADS)

    Lin, Lao-Sheng

    1997-12-01

    When radio waves such as the GPS signals propagate through the ionosphere, they experience an extra time delay. The ionospheric delay can be eliminated (to the first order) through a linear combination of L1 and L2 observations from dual-frequency GPS receivers. Taking advantage of this dispersive principle, one or more dual- frequency GPS receivers can be used to determine a model of the ionospheric delay across a region of interest and, if implemented in real-time, can support single-frequency GPS positioning and navigation applications. The research objectives of this thesis were: (1) to develop algorithms to obtain accurate absolute Total Electron Content (TEC) estimates from dual-frequency GPS observables, and (2) to develop an algorithm to improve the accuracy of real-time ionosphere modelling. In order to fulfil these objectives, four algorithms have been proposed in this thesis. A 'multi-day multipath template technique' is proposed to mitigate the pseudo-range multipath effects at static GPS reference stations. This technique is based on the assumption that the multipath disturbance at a static station will be constant if the physical environment remains unchanged from day to day. The multipath template, either single-day or multi-day, can be generated from the previous days' GPS data. A 'real-time failure detection and repair algorithm' is proposed to detect and repair the GPS carrier phase 'failures', such as the occurrence of cycle slips. The proposed algorithm uses two procedures: (1) application of a statistical test on the state difference estimated from robust and conventional Kalman filters in order to detect and identify the carrier phase failure, and (2) application of a Kalman filter algorithm to repair the 'identified carrier phase failure'. A 'L1/L2 differential delay estimation algorithm' is proposed to estimate GPS satellite transmitter and receiver L1/L2 differential delays. This algorithm, based on the single-site modelling technique, is

  15. Nondestructive and Real-time Measurement of Moisture in Plant

    NASA Astrophysics Data System (ADS)

    Ogawa, Yuichi; Kawase, Kodo; Mizuno, Maya; Yamashita, Masatsugu; Otani, Chiko

    We constructed a THz transillumination system for water content monitoring, and we succeeded in measuring the moisture level in plants. Our measurement system uses a widely tunable coherent THz parametric oscillator source. As target we chose for this experiment a leaf of Japanese basil. The time variation of the water content in the leaf was monitored in two situations: a leaf freshly cut which is left to dry out, and the leaf of a water stressed plant. We found by real-time measurements that the water content of a cut leaf does not decrease uniformly in time. Also, the response to water stress is delayed by about 5-10 minutes. Furthermore, we demonstrated a moisture measurement using a transillumination THz imaging system. As target we chose for this experiment a leaf of Hedera helix held between two thin plastic sheets. The change of the moisture distribution is clearly visible. These results show that the method described here can be applied to nondestructive and real-time monitoring of water content in plants.

  16. TRANSIENT, REAL-TIME, PARTICULATE EMISSION MEASUREMENTS IN DIESEL ENGINES

    SciTech Connect

    Gupta, S; Shih, J; Hillman, G; sekar, R; Graze, R; Shimpi, S; Martin, W; Pier, D

    2003-08-24

    This paper reports our efforts to develop an instrument, TG-1, to measure particulate emissions from diesel engines in real-time. TG-1 while based on laser-induced incandescence allows measurements at 10 Hz on typical engine exhausts. Using such an instrument, measurements were performed in the exhaust of a 1.7L Mercedes Benz engine coupled to a low inertia dynamometer. Comparative measurements performed under engine steady state conditions showed the instrument to agree within {+-}12% of measurements performed with an SMPS. Moreover, the instrument had far better time response and time resolution than a TEOM{reg_sign} 1105. Also, TG-1 appears to surpass the shortcomings of the TEOM instrument, i.e., of yielding negative values under certain engine conditions and, being sensitive to external vibration.

  17. Real-Time Coil Position Monitoring System for Biomagnetic Measurements

    NASA Astrophysics Data System (ADS)

    Oyama, Daisuke; Adachi, Yoshiaki; Higuchi, Masanori; Kawai, Jun; Kobayashi, Koichiro; Uehara, Gen

    In this paper, we propose a new method for monitoring the position of marker coils. The marker coil is used for indicating spatial relationship between subject's body and magnetic sensor arrays in biomagnetic measurements, such as magnetoencephalography (MEG) and magnetocardiography (MCG). We developed a real-time marker coil position monitoring system combined with a conventional MEG system. In order to achieve simultaneous measurement of MEG signals and marker signals, we separated their frequency bands. The frequency bands of flux-locked loop (FLL) circuits were separated into three parts by three integrators; low-band, mid-band, and high-band. The second and third bands were assigned for MEG signals and marker signals, respectively. This method can avoid the crosstalk of the marker signals to MEG signals. Marker signals were generated from five marker coils driven by five independent sinusoidal current generators. These signals were continuously measured by the high-band of FLL, and then the coils were localized by FFT processing and solving inverse problem. We succeeded in displaying the localized coil position on a PC monitor once per second in real-time.

  18. Real-Time performance measurements of EPICS IOCcore.

    SciTech Connect

    Xu, S.; Kraimer, M. R.; Accelerator Systems Division

    2005-01-01

    As the Experimental Physics and Industrial Control System (EPICS) is used in an increasing number of accelerator control systems, EPICS IOCcore is ported to a wider variety of OS platforms and thus the performance of EPICS IOCcore on different hardware and software platforms becomes more important. This paper provides real-time performance measurements of EPICS IOCcore on a VME hardware platform and on three different OS platforms: vxWorks, RTEMS, and Linux. EPICS Input/Output Controller core (IOCcore) software has been ported to several different operating systems (OSs) and many hardware platforms. This paper compares the EPICS IOCcore runtime performance on one hardware platform (MVME2100 PowerPC) and three popular Operating Systems: vxWorks, RTEMS, and Linux. For Linux the following versions were tested: Linux 2.4.2 hard hat 2.0, standard Linux 2.4.30, and Linux 2.6.13. For Linux 2.6.13, the kernel was built both preemptive and non-preemptive. Three real-time parameters are measured: interrupt, context switch, and total response latency. On Linux, more detailed interrupt latencies are measured: interrupt top half to bottom half, and interrupt bottom half to user space interrupt service routine. To implement the tests, several software components were developed. In order to port to other operating systems or hardware platforms only, one component has to be implemented.

  19. Real-time background suppression during frequency domain lifetime measurements.

    PubMed

    Herman, Petr; Maliwal, Badri P; Lakowicz, Joseph R; Maliwal, Baldri P

    2002-10-01

    We describe real time background suppression of autofluorescence from biological samples during frequency domain or phase modulation measurements of intensity decays. For these measurements the samples were excited with a train of light pulses with widths below 1 ps. The detector was gated off for a short time period of 10 to 40 ns during and shortly after the excitation pulse. The reference signal needed for the frequency domain measurement was provided by a long-lifetime reference fluorophore which continues to emit following the off-gating pulse. Both the sample and the reference were measured under identical optical and electronic conditions avoiding the need for correction of the photomultiplier tube signal for the gating sequence. We demonstrate frequency domain background suppression using a mixture of short- and long-lifetime probes and for a long-lifetime probe in human plasma with significant autofluorescence. PMID:12381357

  20. Real-time control of sewer systems using turbidity measurements.

    PubMed

    Lacour, C; Schütze, M

    2011-01-01

    Real-time control (RTC) of urban drainage systems has been proven useful as a means to reduce pollution by combined sewer overflow discharges. So far, RTC has been investigated mainly with a sole focus on water quantity aspects. However, as measurement techniques for pollution of wastewater are advancing, pollution-based RTC might be of increasing interest. For example, turbidity data sets from an extensive measurement programme in two Paris catchments allow a detailed investigation of the benefits of using pollution-based data for RTC. This paper exemplifies this, comparing pollution-based RTC with flow-based RTC. Results suggest that pollution-based RTC indeed has some potential, particularly when measurements of water-quality characteristics are readily available. PMID:22049758

  1. Real time bunch length measurements in the SLC linac

    SciTech Connect

    Sheppard, J.C.; Clendenin, J.E.; James, M.B.; Miller, R.H.; Ross, M.C.

    1985-02-01

    The longitudinal charge distribution of bunches accelerated in the Stanford Linear Collider (SLC) linac will strongly affect the performance of the Collider. Bunch lengths are chosen in a balance between the deleterious effects of longitudinal and transverse wakefields. The former impacts on the beam energy spread whereas the latter is important to the transverse emittance. Two bunch length measurement ports have been installed in the SLC linac: one in the injector region and one after the emittance damping ring to linac reinjection point. These ports utilize a fused quartz Cerenkov radiator in conjunction with an electrooptic streak camera to permit real time monitoring of single s-band buckets with a resolution of several picoseconds. The design of the radiators and light collection optics is discussed with an emphasis on those issues important to high resolution. Experimental results are presented. 7 refs., 4 figs.

  2. Real-time diamagnetic flux measurements on ASDEX Upgrade.

    PubMed

    Giannone, L; Geiger, B; Bilato, R; Maraschek, M; Odstrčil, T; Fischer, R; Fuchs, J C; McCarthy, P J; Mertens, V; Schuhbeck, K H

    2016-05-01

    Real-time diamagnetic flux measurements are now available on ASDEX Upgrade. In contrast to the majority of diamagnetic flux measurements on other tokamaks, no analog summation of signals is necessary for measuring the change in toroidal flux or for removing contributions arising from unwanted coupling to the plasma and poloidal field coil currents. To achieve the highest possible sensitivity, the diamagnetic measurement and compensation coil integrators are triggered shortly before plasma initiation when the toroidal field coil current is close to its maximum. In this way, the integration time can be chosen to measure only the small changes in flux due to the presence of plasma. Two identical plasma discharges with positive and negative magnetic field have shown that the alignment error with respect to the plasma current is negligible. The measured diamagnetic flux is compared to that predicted by TRANSP simulations. The poloidal beta inferred from the diamagnetic flux measurement is compared to the values calculated from magnetic equilibrium reconstruction codes. The diamagnetic flux measurement and TRANSP simulation can be used together to estimate the coupled power in discharges with dominant ion cyclotron resonance heating. PMID:27250425

  3. Designing Information Measures for Real-time Lightcurve Classification

    NASA Astrophysics Data System (ADS)

    Jones, David Edward; Chen, Yang; Meng, Xiao-Li; Siemiginowska, Aneta; Kashyap, Vinay

    2016-01-01

    Since telescope time is limited, real-time lightcurve classification involves carefully selecting future time points at which sources must be observed in order to maximize the information that will be gained for classification. We propose a framework for constructing measures of information for testing/classification/model-selection and demonstrate their use in experimental design. Degroot (1962) developed a general framework for constructing Bayesian measures of the expected information that an experiment will provide for estimation, and our framework analogously constructs measures of information for hypothesis testing. Such test information measures are most useful for model selection and classification problems. Indeed, our framework suggests a probability based measure of test information, which in decision problems has more appealing properties than variance based measures. In the case of lightcurve classification, we adapt our designs to penalize long waits until the next observation time. Lastly, we consider ways to address other aspects of the problem, such as uncertainty estimation arising due to contamination from nearby contaminating sources or background diffuse emission. We acknowledge support from Smithsonian Competitive Grants Fund 40488100HH0043 and NSF grant DMS 1208791.

  4. Accuracy of real time radiography burning rate measurement

    NASA Astrophysics Data System (ADS)

    Olaniyi, Bisola

    The design of a solid propellant rocket motor requires the determination of a propellant's burning-rate and its dependency upon environmental parameters. The requirement that the burning-rate be physically measured, establishes the need for methods and equipment to obtain such data. A literature review reveals that no measurement has provided the desired burning rate accuracy. In the current study, flash x-ray modeling and digitized film-density data were employed to predict motor-port area to length ratio. The pre-fired port-areas and base burning rate were within 2.5% and 1.2% of their known values, respectively. To verify the accuracy of the method, a continuous x-ray and a solid propellant rocket motor model (Plexiglas cylinder) were used. The solid propellant motor model was translated laterally through a real-time radiography system at different speeds simulating different burning rates. X-ray images were captured and the burning-rate was then determined. The measured burning rate was within 1.65% of the known values.

  5. Real-time Measurements of Biological Aerosol Particles in Clouds

    NASA Astrophysics Data System (ADS)

    Twohy, C. H.; McMeeking, G. R.; DeMott, P. J.; Toohey, D. W.; Kok, G.; McCluskey, C.; Hill, T. C.

    2013-12-01

    Some types of biological particles are known to efficiently nucleate ice at relatively warm temperatures in the atmosphere, with the potential to influence cloud microphysical properties and climate. However, the prevalence (or lack thereof) of these particle types in different parts of the atmosphere and in clouds is a matter of debate. Current techniques are mostly limited to near-ground sampling or to limited aircraft sampling with complex instrumentation. Many types of biological particles fluoresce when exposed to ultraviolet light, and the Wideband Integrated Bioaerosol Sensor (WIBS-4A) takes advantage of this characteristic to perform real-time measurements of biological particles. During the IDEAS-2013 test campaign based in Colorado (USA), the WIBS-4A was flown behind a counterflow virtual impactor (CVI) to measure concentrations of biological particles in clouds of different types, temperatures, and altitudes. Preliminary results from this first-ever combination of instruments on the high-performance Gulfstream-V research aircraft will be presented. Concentrations of fluorescent particles measured by the WIBS will also be related to ice nuclei concentrations and properties of particles collected simultaneously on filters.

  6. Real-Time Dopamine Measurement in Awake Monkeys

    PubMed Central

    Schluter, Erik W.; Mitz, Andrew R.; Cheer, Joseph F.; Averbeck, Bruno B.

    2014-01-01

    Fast-scan cyclic voltammetry (FSCV) is often used to measure real-time dopamine (DA) concentrations in awake, behaving rodents. Extending this technique to work in monkeys would provide a platform for advanced behavioral studies and a primate model for preclinical research. The present study demonstrates the feasibility of DA recordings in two awake monkeys (Macaca mulatta) using a mixture of techniques adapted from rodent, primate and brain slice work. We developed a long carbon fiber electrode to operate in the larger primate brain. This electrode was lowered into the striatum each day using a recording chamber and a detachable micromanipulator system. A manipulator also moved one or more tungsten stimulating electrodes into either the nearby striatum or the ventral tegmental area/substantia nigra pars compacta (VTA/SNc). We developed an electrical stimulation controller to reduce artifacts during electrical stimulation. We also introduce a stimulation-based methodology for estimating distances between electrodes in the brain. Dopamine responses within the striatum were evoked by either stimulation of the striatum near the FSCV electrode, or stimulation within the VTA/SNc. Unexpected juice rewards also evoked dopamine responses in the ventral striatum. Thus, we demonstrate that robust dopamine responses can be recorded from awake, behaving primates with FSCV. In addition, we describe how a stimulation technique borrowed from the neuroprosthetics field can activate the distributed monkey midbrain dopamine system in a way that mimics rodent VTA stimulation. PMID:24921937

  7. Real-time dopamine measurement in awake monkeys.

    PubMed

    Schluter, Erik W; Mitz, Andrew R; Cheer, Joseph F; Averbeck, Bruno B

    2014-01-01

    Fast-scan cyclic voltammetry (FSCV) is often used to measure real-time dopamine (DA) concentrations in awake, behaving rodents. Extending this technique to work in monkeys would provide a platform for advanced behavioral studies and a primate model for preclinical research. The present study demonstrates the feasibility of DA recordings in two awake monkeys (Macaca mulatta) using a mixture of techniques adapted from rodent, primate and brain slice work. We developed a long carbon fiber electrode to operate in the larger primate brain. This electrode was lowered into the striatum each day using a recording chamber and a detachable micromanipulator system. A manipulator also moved one or more tungsten stimulating electrodes into either the nearby striatum or the ventral tegmental area/substantia nigra pars compacta (VTA/SNc). We developed an electrical stimulation controller to reduce artifacts during electrical stimulation. We also introduce a stimulation-based methodology for estimating distances between electrodes in the brain. Dopamine responses within the striatum were evoked by either stimulation of the striatum near the FSCV electrode, or stimulation within the VTA/SNc. Unexpected juice rewards also evoked dopamine responses in the ventral striatum. Thus, we demonstrate that robust dopamine responses can be recorded from awake, behaving primates with FSCV. In addition, we describe how a stimulation technique borrowed from the neuroprosthetics field can activate the distributed monkey midbrain dopamine system in a way that mimics rodent VTA stimulation. PMID:24921937

  8. DNA detection of Clostridium difficile infection based on real-time resistance measurement.

    PubMed

    Liu, C; Jiang, D N; Xiang, G M; Luo, F K; Liu, L L; Yu, J C; Pu, X Y

    2013-01-01

    We used a newly developed electrochemical method, real-time resistance measurement, based on loop-mediated isothermal amplification (LAMP), with real-time resistance monitoring and derivative analysis. DNA extracted from specimens was amplified through LAMP reaction. The 2 products of LAMP, DNA and pyrophosphate, both are negative ions; they combine with positive dye (crystal violet) and positive ions (Mg(2+)), which leads to an increase in the resistivity of the reaction liquid. The changes of resistivity were measured in real-time with a specially designed resistance electrode, to detect Clostridium difficile DNA. We found that electrochemical detection of C. difficile could be completed in 0.5-1 h, with a detection limit of 10(2) CFU/mL, with high accuracy (95.0%), sensitivity (91.1%), and specificity (97.3%) compared to PCR methods. C. difficile is commonly associated with antibiotic-induced diarrhea. Due to the difficulty in performing anaerobic culture and cytotoxicity neutralization assays, a simple, rapid, sensitive, and accurate method is preferred. We conclude that real-time resistance measurement is a rapid, sensitive, and stable method for the diagnosis of C. difficile infection that could be applied to gene chips and pocket instruments. PMID:24065671

  9. A virtual instrument for real time in vivo measurement of carotid artery compliance.

    PubMed

    Joseph, Jayaraj; Jayashankar, V

    2008-01-01

    A new virtual instrument for real time, non invasive measurement of carotid artery compliance is proposed. The instrument is a reliable, compact and low cost alternative to the conventional ultrasound scanner and wall tracking system for carotid artery compliance measurement. The measurement system uses an ultrasound pulse echo method to probe the carotid artery. The reflected echoes are processed using Hilbert transform techniques. Peak detection and echo tracking are implemented in LabVIEW. A comparison is done between manual and automatic method of echo identification. The instrument gives a display of the variation of carotid diameter in real time and calculates the various estimates of arterial compliance from the analyzed data. The capability of the instrument to accurately determine arterial compliance measures is demonstrated by experiments performed on human subjects. PMID:19163155

  10. Real-time wavefront reconstruction from intensity measurements

    NASA Astrophysics Data System (ADS)

    Smith, Carlas; Marinica, Raluca; Verhaegen, Michel

    2013-12-01

    We propose an ecient approximation to the nonlinear phase diversity method for wavefront reconstruction method from intensity measurements in order to avoid the shortcomings of the nonlinear phase diversity method that prevent its real-time application, such as its computationally complex and the presence of local minima. The new method is called linear sequential phase diversity (LSPD). The method assumes that residual phase aberration is small and makes use of a rst order Taylor expansion of the point spread function (PSF). The Taylor expansion is performed in two dierent phase diversities, that can be arbitrary (large) pupil shapes in order to optimize the phase retrieval. For static aberrations LSPD makes use of two images that are collected at each iteration step of the algorithm. In each step the residual phase aberrations are estimated by solving a linear least squares problem, followed by the use of a deformable mirror to correct for the aberrations. The computational complexity of LSPD is O(m*m) - where m*m is the number of pixels. For the static case the convergence of the LSPD iterations have been studied and experimentally veried. In an extensive comparison the method is compared with the recently proposed method of [1]. This study demonstrates the improved performance both computationally and in accuracy with respect to existing competitors that also linearize the PSF. A further contribution of the paper is that we extend the static LSPD method to the case of dynamic wavefront reconstruction based on intensity measurements. Here the dynamics are assumed to be modelled standardly by a linear innovation model such that its spectrum e.g. approximates that given by Kolmogorov. The advantage of the application of the dynamic variant of the LSPD method is that in closed-loop the assumption that the residual phase aberration is small is justiable, since the goal of the controller is to reduce (minimize) the residual phase aberration. This unique contribution

  11. Real-Time Aerodynamic Parameter Estimation without Air Flow Angle Measurements

    NASA Technical Reports Server (NTRS)

    Morelli, Eugene A.

    2010-01-01

    A technique for estimating aerodynamic parameters in real time from flight data without air flow angle measurements is described and demonstrated. The method is applied to simulated F-16 data, and to flight data from a subscale jet transport aircraft. Modeling results obtained with the new approach using flight data without air flow angle measurements were compared to modeling results computed conventionally using flight data that included air flow angle measurements. Comparisons demonstrated that the new technique can provide accurate aerodynamic modeling results without air flow angle measurements, which are often difficult and expensive to obtain. Implications for efficient flight testing and flight safety are discussed.

  12. Real-time measurement of engine oil economy

    SciTech Connect

    Butler, J.W.; Korniski, T.; Calvin, A.D.; Jary, E.H.

    1987-01-01

    A coulometric SO/sub 2/ monitor has been developed to measure SO/sub 2/ generated from combustion of S in oil to determine engine oil consumption. Sulfur-free fuel is used to eliminate background levels of SO/sub 2/. Addition of an SO/sub 2/ standard gas to the engine during test insures accurate normalization of sampling system flows and quantitative measurement of engine oil economy. Precision of the SO/sub 2/ microcoulometer technique was better than +-8%. The SO/sub 2/ microcoulometer is used during steady state engine operation, and may be used in determining oil consumption from individual cylinders. Existence of engine oil consumption via an aerosol mechanism is investigated and measured. Effects of engine operating temperature and positive crankcase ventilation (PCV) on engine oil economy are given.

  13. Real-Time Data-Acquisition Platform for Pulsed Measurements

    NASA Astrophysics Data System (ADS)

    Polyakov, Sergey V.; Migdall, Alan; Nam, Sae Woo

    2011-03-01

    We present an inexpensive and simple data acquisition platform based on Field Programmable Gate Arrays (FPGAs) designed to acquire and characterize fast digital or analog electrical signals in real time for processing on a generic personal computer. While the instrument was designed for electrical outputs of single-photon detectors and is suited for high photon-counting rates, it can also be used for characterization of similar digital electrical signals from other sources and for analog signals as well. The complete description of the platform is available for download at http://physics.nist.gov/fpga.

  14. Real-time precision measuring device of tree diameter growth

    NASA Astrophysics Data System (ADS)

    Guo, Mingming; Chen, Aijun; Li, Dongsheng; Liu, Nan; Yao, Jingyuan

    2016-01-01

    DBH(diameter at breast height) is an important factor to reflect of the quality of plant growth, also an important parameter indispensable in forest resources inventory and forest carbon sink, the accurate measurement of DBH or not is directly related to the research of forest resources inventory and forest carbon sink. In this paper, the principle and the mathematical model of DBH measurement device were introduced, the fixture measuring device and the hardware circuit for this tree diameter were designed, the measurement software programs were compiled, and the precision measuring device of tree diameter growth was developed. Some experiments with Australia fir were conducted. Based on experiment data, the correlations among the DBH variation of Australian fir, the environment temperature, air humility and PAR(photosynthetically active radiation) were obtained. The effects of environmental parameters (environment temperature, air humility and PAR) on tree diameter were analyzed. Experimental results show that there is a positive correlation between DBH variation of Australian fir and environment temperature, a negative correlation between DBH variation of Australian fir and air humility , so is PAR.

  15. Real-time measurements, rare events and photon economics

    NASA Astrophysics Data System (ADS)

    Jalali, B.; Solli, D. R.; Goda, K.; Tsia, K.; Ropers, C.

    2010-07-01

    Rogue events otherwise known as outliers and black swans are singular, rare, events that carry dramatic impact. They appear in seemingly unconnected systems in the form of oceanic rogue waves, stock market crashes, evolution, and communication systems. Attempts to understand the underlying dynamics of such complex systems that lead to spectacular and often cataclysmic outcomes have been frustrated by the scarcity of events, resulting in insufficient statistical data, and by the inability to perform experiments under controlled conditions. Extreme rare events also occur in ultrafast physical sciences where it is possible to collect large data sets, even for rare events, in a short time period. The knowledge gained from observing rare events in ultrafast systems may provide valuable insight into extreme value phenomena that occur over a much slower timescale and that have a closer connection with human experience. One solution is a real-time ultrafast instrument that is capable of capturing singular and randomly occurring non-repetitive events. The time stretch technology developed during the past 13 years is providing a powerful tool box for reaching this goal. This paper reviews this technology and discusses its use in capturing rogue events in electronic signals, spectroscopy, and imaging. We show an example in nonlinear optics where it was possible to capture rare and random solitons whose unusual statistical distribution resemble those observed in financial markets. The ability to observe the true spectrum of each event in real time has led to important insight in understanding the underlying process, which in turn has made it possible to control soliton generation leading to improvement in the coherence of supercontinuum light. We also show a new class of fast imagers which are being considered for early detection of cancer because of their potential ability to detect rare diseased cells (so called rogue cells) in a large population of healthy cells.

  16. Real-time measurements of local myocardium motion and arterial wall thickening.

    PubMed

    Kanai, H; Koiwa, Y; Zhang, J

    1999-01-01

    We have already developed a new method, namely, the phased tracking method, to track the movement of the heart wall and arterial wall accurately based on both the phase and magnitude of the demodulated signals to determine the instantaneous position of an object. This method has been realized by an off-line measurement system, which cannot be applied to transient evaluation of rapid response of the cardiovascular system to physiological stress. In this paper, therefore, a real-time system to measure change in the thickness of the myocardium and the arterial wall is presented. In this system, an analytic signal from standard ultrasonic diagnostic equipment is analogue-to-digital (A/D) converted at a sampling frequency of 1 MHz. By pipelining and parallel processing using four high-speed digital signal processing (DSP) chips, the method described is realized in real time. The tracking results for both sides of the heart and/or arterial wall are superimposed on the M (motion)-mode image in the work station (WS), and the thickness changes of the heart and/or arterial wall are also displayed and digital-to-analogue (D/A) converted in real time. From the regional change in thickness of the heart wall, spatial distribution of myocardial motility and contractility can be evaluated. For the arterial wall, its local elasticity can be evaluated by referring to the blood pressure. In in vivo experiments, the rapid response of the change in wall thickness of the carotid artery to the dose of the nitroglycerine (NTG) is evaluated. This new real-time system offers potential for quantitative diagnosis of myocardial motility, early stage atherosclerosis, and the transient evaluation of the rapid response of the cardiovascular system to physiological stress. PMID:18244316

  17. Measurement of bow tie profiles in CT scanners using a real-time dosimeter

    SciTech Connect

    Whiting, Bruce R.; Evans, Joshua D.; Williamson, Jeffrey F.; Dohatcu, Andreea C.; Politte, David G.

    2014-10-15

    one system produced agreement with a relative error of 2%–6%. Fan beam profiles were found to differ for different filter types on a given system and between different vendors. Conclusions: A commercially available real-time dosimeter probe was found to be a convenient and accurate instrument for measuring fan beam profiles. An analysis method was developed that could handle a wide range of collimation widths by explicitly considering the finite width of the ion chamber. Relative errors in the profiles were found to be less than 5%. Measurements of five different clinical scanners demonstrate the variation in bow tie designs, indicating that generic bow tie models will not be adequate for CT system research.

  18. Real-time measurement system for in-plane displacement and strain based on vision

    NASA Astrophysics Data System (ADS)

    Luo, Tao; Jin, Yi; Zhu, Ye; Zhai, Chao

    2013-08-01

    In this paper, combining optical measurement with conventional material testing machine, a real-time in-plane displacement and strain measurement system is built, which is applied to the material testing machine. This system can realize displacement and strain measurement of a large deformation sample moreover it can observe the sample crack on line. The change of displacement field is obtained through the change of center coordinate of each point of a grid lattice in the surface of the testing sample, according to two-dimensional sort coding for the grid in the traditional automated grid method, in this paper, an improved one-dimensional code method is adopted which make calculating speed much faster and the algorithm more adaptable. The measurement of the stability and precision of this system are made using the calibration board whose position precision is about 1.5 micron. The results show that the short-time stability of this system is about 0.5micron. At last, this system is used for strain measurement in a sample tension test, and the result shows that the system can acquire in-plane displacement and strain measurement results accurately and real-time, the velocity of image processing can reach 10 frame per second; or it can observe sample crack on line and storage the test process, the max velocity of observation and storage is 100 frame per second.

  19. Research progress on real-time measurement of soil attributes for precision agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to develop a real-time analyzer for soil attributes, this study analyzed the needs for real-time measurement of soil attributes and reviewed major soil attributes to be measured in soil testing and commonly-used testing methods, including traditional chemical analysis, methods based on elec...

  20. A REAL-TIME MEASURING DEVICE FOR DENSE PARTICULATE SYSTEMS

    EPA Science Inventory

    The report describes the design and performance of an instrument, based on the concept of instantaneous intensity ratio, for measuring particle size distributions of dense particulate matter. The method involves simultaneously measuring the intensity of light scattered by a parti...

  1. Real time swallowing measurement system by using photometric stereo

    NASA Astrophysics Data System (ADS)

    Fujino, Masahiro; Kato, Kunihito; Mura, Emi; Nagai, Hajime

    2015-04-01

    In this paper, we propose a measurement system to evaluate the swallowing by estimating the movement of the thyroid cartilage. We developed a measurement system based on the vision sensor in order to achieve the noncontact and non-invasive sensor. The movement of the subject's thyroid cartilage is tracked by the three dimensional information of the surface of the skin measured by the photometric stereo. We constructed a camera system that uses near-IR light sources and three camera sensors. We conformed the effectiveness of the proposed system by experiments.

  2. Error Correction for Foot Clearance in Real-Time Measurement

    NASA Astrophysics Data System (ADS)

    Wahab, Y.; Bakar, N. A.; Mazalan, M.

    2014-04-01

    Mobility performance level, fall related injuries, unrevealed disease and aging stage can be detected through examination of gait pattern. The gait pattern is normally directly related to the lower limb performance condition in addition to other significant factors. For that reason, the foot is the most important part for gait analysis in-situ measurement system and thus directly affects the gait pattern. This paper reviews the development of ultrasonic system with error correction using inertial measurement unit for gait analysis in real life measurement of foot clearance. This paper begins with the related literature where the necessity of measurement is introduced. Follow by the methodology section, problem and solution. Next, this paper explains the experimental setup for the error correction using the proposed instrumentation, results and discussion. Finally, this paper shares the planned future works.

  3. Real-Time Inhibitor Recession Measurements in Two Space Shuttle Reusable Solid Rocket Motors

    NASA Technical Reports Server (NTRS)

    McWhorter, B. B.; Ewing, M. E.; Bolton, D. E.; Albrechtsen, K. U.; Earnest, T. E.; Noble, T. C.; Longaker, M.

    2003-01-01

    Real-time internal motor insulation char line recession measurements have been evaluated for two full-scale static tests of the Space Shuttle Reusable Solid Rocket Motor (RSRM). These char line recession measurements were recorded on the forward facing propellant grain inhibitors to better understand the thermal performance of these inhibitors. The RSRM propellant grain inhibitors are designed to erode away during motor operation, thus making it difficult to use post-fire observations to determine inhibitor thermal performance. Therefore, this new internal motor instrumentation is invaluable in establishing an accurate understanding of inhibitor recession versus motor operation time. The data for the first test was presented at the 37th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (AIAA 2001-3280) in July 2001. Since that time, a second full scale static test has delivered additional real-time data on inhibitor thermal performance. The evaluation of this data is presented in this paper. The second static test, in contrast to the first test, used a slightly different arrangement of instrumentation in the inhibitors. This instrumentation has yielded a better understanding of the inhibitor time dependent inboard tip recession. Graphs of inhibitor recession profiles with time are presented. Inhibitor thermal ablation models have been created from theoretical principals. The model predictions compare favorably with data from both tests. This verified modeling effort is important to support new inhibitor designs for a five segment Space Shuttle solid rocket motor. The internal instrumentation project on RSRM static tests is providing unique opportunities for other real-time internal motor measurements that could not otherwise be directly quantified.

  4. GPU-assisted real-time three dimensional shape measurement by speckle-embedded fringe

    NASA Astrophysics Data System (ADS)

    Feng, Shijie; Chen, Qian; Zuo, Chao

    2015-07-01

    This paper presents a novel two-frame method of fringe projection for real-time, accurate and unambiguous threedimensional shape measurement. One of the used frames is a speckle pattern and the other one is a composite image which is fused by that speckle image and sinusoidal fringes. The sinusoidal component is used to retrieve the wrapped phase map. The frame of the speckle is employed to remove the phase ambiguity for the reconstruction of the absolute depth. Compared with traditional multi-frequency phase-shifting methods, the proposed scheme is of much lower sensitivity to movements as the result of the reduced number of used patterns. Moreover, its measuring precision is very close to that of the phase-shifting method, which indicates the method is of high accuracy. To process data in real time, a CUDA-enabled Graphics Processing Unit (GPU) is introduced to accelerate the computations of phase and depth. With our system, measurements can be performed at 21 frames per second with a resolution of 307K points per frame.

  5. A Real-Time Measurement System for Long-Life Flood Monitoring and Warning Applications

    PubMed Central

    Marin-Perez, Rafael; García-Pintado, Javier; Gómez, Antonio Skarmeta

    2012-01-01

    A flood warning system incorporates telemetered rainfall and flow/water level data measured at various locations in the catchment area. Real-time accurate data collection is required for this use, and sensor networks improve the system capabilities. However, existing sensor nodes struggle to satisfy the hydrological requirements in terms of autonomy, sensor hardware compatibility, reliability and long-range communication. We describe the design and development of a real-time measurement system for flood monitoring, and its deployment in a flash-flood prone 650 km2 semiarid watershed in Southern Spain. A developed low-power and long-range communication device, so-called DatalogV1, provides automatic data gathering and reliable transmission. DatalogV1 incorporates self-monitoring for adapting measurement schedules for consumption management and to capture events of interest. Two tests are used to assess the success of the development. The results show an autonomous and robust monitoring system for long-term collection of water level data in many sparse locations during flood events. PMID:22666028

  6. Rethinking data collection and signal processing. 1. Real-time oversampling filter for chemical measurements.

    PubMed

    Laude, Nicholas D; Atcherley, Christopher W; Heien, Michael L

    2012-10-01

    Minimizing noise in chemical measurements is critical to achieve low limits of detection and accurate measurements. We describe a real-time oversampling filter that offers a method to reduce stochastic noise in a time-dependent chemical measurement. The power of this technique is demonstrated in its application to the separation of dopamine and serotonin by micellar electrokinetic chromatography with amperometric detection. Signal-to-noise ratios were increased by almost an order of magnitude, allowing for limits of detection of 100 and 120 amol, respectively. Real-time oversampling filters can be implemented using simple software algorithms and require no change to existing experimental apparatus. The application is not limited to analytical separations, and this technique can be used to improve the signal-to-noise ratio in any experiment where the necessary sampling rate is less than the maximum sampling rate of the analog-to-digital converter. Theory, implementation, and the performance of this filter are described. We propose that this technique should be the default mode of operation for an analog-to-digital converter. PMID:22978644

  7. IN SITU Device for Real-Time Catalyst Deactivation Measurements

    SciTech Connect

    Fossil Energy Research

    2008-03-31

    SCR catalyst management has become an important operations and maintenance activity for coal-fired utility boilers in the United States. To facilitate this activity, a method to determine Catalyst Activity in situ is being developed. This report describes the methodology and presents the results of a two ozone season demonstration conducted at Alabama Power Company's Gorgas Unit 10 during the 2005 and 2006 ozone seasons. The results showed that the in situ measurements are in good agreement with the laboratory measurements and the technique has some advantages over the traditional laboratory method of determining Catalyst Activity and Reactor Potential. SCR Performance is determined by the overall Reactor Potential (the product of the Catalyst Activity and the available surface area per unit of flue gas). The in situ approach provides a direct measurement of Reactor Potential under actual operating conditions, whereas laboratory measurements of Catalyst Activity need to be coupled with estimates of catalyst pluggage and flue gas flowrate in order to assess Reactor Potential. The project also showed that the in situ activity results can easily be integrated into catalyst management software to aid in making informed catalyst decisions.

  8. Accurate real-time depth control for CP-SSOCT distal sensor based handheld microsurgery tools.

    PubMed

    Cheon, Gyeong Woo; Huang, Yong; Cha, Jaepyeng; Gehlbach, Peter L; Kang, Jin U

    2015-05-01

    This paper presents a novel intuitive targeting and tracking scheme that utilizes a common-path swept source optical coherence tomography (CP-SSOCT) distal sensor integrated handheld microsurgical tool. To achieve micron-order precision control, a reliable and accurate OCT distal sensing method is required; simultaneously, a prediction algorithm is necessary to compensate for the system delay associated with the computational, mechanical and electronic latencies. Due to the multi-layered structure of retina, it is necessary to develop effective surface detection methods rather than simple peak detection. To achieve this, a shifted cross-correlation method is applied for surface detection in order to increase robustness and accuracy in distal sensing. A predictor based on Kalman filter was implemented for more precise motion compensation. The performance was first evaluated using an established dry phantom consisting of stacked cellophane tape. This was followed by evaluation in an ex-vivo bovine retina model to assess system accuracy and precision. The results demonstrate highly accurate depth targeting with less than 5 μm RMSE depth locking. PMID:26137393

  9. Accurate real-time depth control for CP-SSOCT distal sensor based handheld microsurgery tools

    PubMed Central

    Cheon, Gyeong Woo; Huang, Yong; Cha, Jaepyeng; Gehlbach, Peter L.; Kang, Jin U.

    2015-01-01

    This paper presents a novel intuitive targeting and tracking scheme that utilizes a common-path swept source optical coherence tomography (CP-SSOCT) distal sensor integrated handheld microsurgical tool. To achieve micron-order precision control, a reliable and accurate OCT distal sensing method is required; simultaneously, a prediction algorithm is necessary to compensate for the system delay associated with the computational, mechanical and electronic latencies. Due to the multi-layered structure of retina, it is necessary to develop effective surface detection methods rather than simple peak detection. To achieve this, a shifted cross-correlation method is applied for surface detection in order to increase robustness and accuracy in distal sensing. A predictor based on Kalman filter was implemented for more precise motion compensation. The performance was first evaluated using an established dry phantom consisting of stacked cellophane tape. This was followed by evaluation in an ex-vivo bovine retina model to assess system accuracy and precision. The results demonstrate highly accurate depth targeting with less than 5 μm RMSE depth locking. PMID:26137393

  10. Joint iris boundary detection and fit: a real-time method for accurate pupil tracking.

    PubMed

    Barbosa, Marconi; James, Andrew C

    2014-08-01

    A range of applications in visual science rely on accurate tracking of the human pupil's movement and contraction in response to light. While the literature for independent contour detection and fitting of the iris-pupil boundary is vast, a joint approach, in which it is assumed that the pupil has a given geometric shape has been largely overlooked. We present here a global method for simultaneously finding and fitting of an elliptic or circular contour against a dark interior, which produces consistently accurate results even under non-ideal recording conditions, such as reflections near and over the boundary, droopy eye lids, or the sudden formation of tears. The specific form of the proposed optimization problem allows us to write down closed analytic formulae for the gradient and the Hessian of the objective function. Moreover, both the objective function and its derivatives can be cast into vectorized form, making the proposed algorithm significantly faster than its closest relative in the literature. We compare methods in multiple ways, both analytically and numerically, using real iris images as well as idealizations of the iris for which the ground truth boundary is precisely known. The method proposed here is illustrated under challenging recording conditions and it is shown to be robust. PMID:25136477

  11. Adaptive, real-time hypoxia measurements using an autonomous boat

    NASA Astrophysics Data System (ADS)

    Kerkez, B.; Wong, B. P.; Balzano, L.; Lipor, J.; Scavia, D.

    2015-12-01

    We present an autonomous system to measure hypoxia at high spatial resolutions. The approach combines a robotic boat, cloud hosted data services, and a suite of adaptive sampling algorithms to minimize the number of samples required to delineate hypoxic extents. The boat lowers sensors into the water column to provide depth profiles of temperature and oxygen concentrations. An adaptive path-planning algorithm continuously analyzes the in-situ observations and directs the boat to its next measurement location. This significantly reduces number of samples compared to a gridded sampling approach, while simultaneously improving the certainty with which the hypoxic regions are delineated. The method has been evaluated on small lakes throughout Michigan and shows significant promise to scale to the Great Lakes, where hypoxia is common occurrence that adversely affects various stakeholder and ecosystems.

  12. Real Time Turbulence Estimation Using Doppler Lidar Measurements

    NASA Astrophysics Data System (ADS)

    Rottner, Lucie; Baehr, Christophe

    2016-06-01

    A preliminary work on a new way to estimate atmospheric turbulence using high-frequency Doppler lidar measurements is presented. The turbulence estimations are based on wind reconstruction using 3D Doppler lidar observations and a particle filter. The suggested reconstruction algorithm links the lidar observations to numerical particles to obtain turbulence estimations every time new observations are available. The high frequency of the estimations is a new point which is detailed and discussed. Moreover, the presented algorithm ables to reconstruct the wind in three dimensions in the observed volume. We have thus locally access to the spatial variability of the turbulent atmosphere. The suggested algorithm is applied to a set of real observations. The obtained results are very encouraging : they show significant improvements on turbulent parameter estimations.

  13. Toward Real-Time Automated Detection of Turns during Gait Using Wearable Inertial Measurement Units

    PubMed Central

    Novak, Domen; Goršič, Maja; Podobnik, Janez; Munih, Marko

    2014-01-01

    Previous studies have presented algorithms for detection of turns during gait using wearable sensors, but those algorithms were not built for real-time use. This paper therefore investigates the optimal approach for real-time detection of planned turns during gait using wearable inertial measurement units. Several different sensor positions (head, back and legs) and three different detection criteria (orientation, angular velocity and both) are compared with regard to their ability to correctly detect turn onset. Furthermore, the different sensor positions are compared with regard to their ability to predict the turn direction and amplitude. The evaluation was performed on ten healthy subjects who performed left/right turns at three amplitudes (22, 45 and 90 degrees). Results showed that turn onset can be most accurately detected with sensors on the back and using a combination of orientation and angular velocity. The same setup also gives the best prediction of turn direction and amplitude. Preliminary measurements with a single amputee were also performed and highlighted important differences such as slower turning that need to be taken into account. PMID:25310470

  14. Real-Time Measurement of Rates of Outdoor Airflow into HVACSystems: A Field Study of Three Technologies

    SciTech Connect

    Fisk, William J.; Sullivan, Douglas P.; Faulkner, David

    2005-09-01

    Technologies for real-time continuous measurement of the flow rates of outdoor air (OA) into HVAC systems are now available commercially. Our prior papers reported on laboratory-based evaluations of these measurement technologies and this document describes the methods and results of a field study of the accuracy of three of these technologies. From the field study data, we determined that neither wind speed nor wind direction have an important adverse impact on measurement accuracy. The field study confirmed that these three measurement technologies can provide reasonably accurate measurements of outdoor air intake rates in field settings, if the pressure signals are measured with high accuracy. Some of the pressure transducers marketed for use with commercial HVAC systems were determined to be sufficiently accurate for this application. Given the significant impact of OA flow rates on both energy use and occupant health, more widespread use of technologies that provide for real time measurements of OA flow rates seems warranted.

  15. Monitoring and simulating real-time electric power system operation with phasor measurements

    SciTech Connect

    Phadke, A.G.; Thorp, J.S.

    1995-01-01

    In this research project, two important results have been achieved. The concept of generator axis load flow has been developed more fully, and has been tested through simulations on the 39-bus system (with 10 generators). Generator axis load flow is a load flow calculation which views the entire network from a few retained buses such as the internal nodes of the generators. As these nodes can be indirectly monitored in real time through phasor measurements of generator terminal quantities, it becomes possible to track and predict the behavior of the entire network from these few observation points. This is extremely valuable in the task of predicting network instability in real time. The task of instability prediction of a multi-machine power system is one of the most difficult analytical exercises. We investigated two of the most promising approaches: the extended equal area method, and the transient energy function method. Although both of these methods work well in many instances, we have shown that in other cases, the predictions made by the two methods are incorrect. The failure of the methods can be traced to their inability to deal with the behavior of the system after the first turning point of the motor swing curves. Instead of using these methods, we propose the direct integration of the machine swing equations following the start of a disturbance. Coupled with the generator aids load flow developed above, and using the high speed computers available now, we show that for systems of significant size (39 bus system), accurate predictions through direct computation are possible. The report also includes results on computational efficiency of the method of faster-than-real-time integration using machine equations and the generator aids load flow. It is anticipated that this technique will be useful in most practical applications in power system control centers of the future.

  16. Advanced video extensometer for non-contact, real-time, high-accuracy strain measurement.

    PubMed

    Pan, Bing; Tian, Long

    2016-08-22

    We developed an advanced video extensometer for non-contact, real-time, high-accuracy strain measurement in material testing. In the established video extensometer, a "near perfect and ultra-stable" imaging system, combining the idea of active imaging with a high-quality bilateral telecentric lens, is constructed to acquire high-fidelity video images of the test sample surface, which is invariant to ambient lighting changes and small out-of-plane motions occurred between the object surface and image plane. In addition, an efficient and accurate inverse compositional Gauss-Newton algorithm incorporating a temporal initial guess transfer scheme and a high-accuracy interpolation method is employed to achieve real-time, high-accuracy displacement tracking with negligible bias error. Tensile tests of an aluminum sample and a carbon fiber filament sample were performed to demonstrate the efficiency, repeatability and accuracy of the developed advanced video extensometer. The results indicate that longitudinal and transversal strains can be estimated and plotted at a rate of 117 fps and with a maximum strain error less than 30 microstrains. PMID:27557188

  17. An Accurate, Flexible and Small Optical Fiber Sensor: A Novel Technological Breakthrough for Real-Time Analysis of Dynamic Blood Flow Data In Vivo

    PubMed Central

    Yuan, Qiao-ying; Zhang, Ling; Xiao, Dan; Zhao, Kun; Lin, Chun; Si, Liang-yi

    2014-01-01

    Because of the limitations of existing methods and techniques for directly obtaining real-time blood data, no accurate microflow in vivo real-time analysis method exists. To establish a novel technical platform for real-time in vivo detection and to analyze average blood pressure and other blood flow parameters, a small, accurate, flexible, and nontoxic Fabry-Perot fiber sensor was designed. The carotid sheath was implanted through intubation of the rabbit carotid artery (n = 8), and the blood pressure and other detection data were determined directly through the veins. The fiber detection results were compared with test results obtained using color Doppler ultrasound and a physiological pressure sensor recorder. Pairwise comparisons among the blood pressure results obtained using the three methods indicated that real-time blood pressure information obtained through the fiber sensor technique exhibited better correlation than the data obtained with the other techniques. The highest correlation (correlation coefficient of 0.86) was obtained between the fiber sensor and pressure sensor. The blood pressure values were positively related to the total cholesterol level, low-density lipoprotein level, number of red blood cells, and hemoglobin level, with correlation coefficients of 0.033, 0.129, 0.358, and 0.373, respectively. The blood pressure values had no obvious relationship with the number of white blood cells and high-density lipoprotein and had a negative relationship with triglyceride levels, with a correlation coefficient of –0.031. The average ambulatory blood pressure measured by the fiber sensor exhibited a negative correlation with the quantity of blood platelets (correlation coefficient of −0.839, P<0.05). The novel fiber sensor can thus obtain in vivo blood pressure data accurately, stably, and in real time; the sensor can also determine the content and status of the blood flow to some extent. Therefore, the fiber sensor can obtain partially real-time

  18. AUTOMATED CONTROL AND REAL-TIME DATA PROCESSING OF WIRE SCANNER/HALO SCRAPER MEASUREMENTS

    SciTech Connect

    L.A. DAY; J.D. GILPATRICK; ET AL

    2001-06-01

    The Low-Energy Demonstration Accelerator (LEDA), assembled and operating at Los Alamos National Laboratory, provides the platform for obtaining measurements of high-power proton beam-halo formation. Control system software and hardware have been integrated and customized to enable the production of real-time beam-halo profiles. The Experimental Physics and Industrial Control System (EPICS) hosted on a VXI platform, Interactive Data Language (IDL) programs hosted on UNIX platforms, and LabVIEW (LV) Virtual Instruments hosted on a PC platform have been integrated and customized to provide real-time, synchronous motor control, data acquisition, and data analysis of data acquired through specialized DSP instrumentation. These modules communicate through EPICS Channel Access (CA) communication protocol extensions to control and manage execution flow ensuring synchronous data acquisition and real-time processing of measurement data. This paper describes the software integration and management scheme implemented to produce these real-time beam profiles.

  19. Providing accurate near real-time fire alerts for Protected Areas through NASA FIRMS: Opportunities and Challenges

    NASA Astrophysics Data System (ADS)

    Ilavajhala, S.; Davies, D.; Schmaltz, J. E.; Wong, M.; Murphy, K. J.

    2013-12-01

    The NASA Fire Information for Resource Management System (FIRMS) is at the forefront of providing global near real-time (NRT) MODIS thermal anomalies / hotspot location data to end-users . FIRMS serves the data via an interactive Web GIS named Web Fire Mapper, downloads of NRT active fire, archive data downloads for MODIS hotspots dating back to 1999 and a hotspot email alert system The FIRMS Email Alerts system has been successfully alerting users of fires in their area of interest in near real-time and/or via daily and weekly email summaries, with an option to receive MODIS hotspot data as a text file (CSV) attachment. Currently, there are more than 7000 email alert subscriptions from more than 100 countries. Specifically, the email alerts system is designed to generate and send an email alert for any region or area on the globe, with a special focus on providing alerts for protected areas worldwide. For many protected areas, email alerts are particularly useful for early fire detection, monitoring on going fires, as well as allocating resources to protect wildlife and natural resources of particular value. For protected areas, FIRMS uses the World Database on Protected Areas (WDPA) supplied by United Nations Environment Program - World Conservation Monitoring Centre (UNEP-WCMC). Maintaining the most up-to-date, accurate boundary geometry for the protected areas for the email alerts is a challenge as the WDPA is continuously updated due to changing boundaries, merging or delisting of certain protected areas. Because of this dynamic nature of the protected areas database, the FIRMS protected areas database is frequently out-of-date with the most current version of WDPA database. To maintain the most up-to-date boundary information for protected areas and to be in compliance with the WDPA terms and conditions, FIRMS needs to constantly update its database of protected areas. Currently, FIRMS strives to keep its database up to date by downloading the most recent

  20. In-Situ Real Time Measurements of Molten Glass Properties, Final Report

    SciTech Connect

    Robert De Saro; Joe Craparo

    2007-12-16

    Energy Research Company (ERCo) of Staten Island, NY has developed a sensor capable of measuring in situ and in real time, both the elemental composition and the temperature of molten glass. A prototype sensor has been designed, constructed and tested in ERCo's laboratory. The sensor was used to collect atomic emission spectra from molten fiberglass via Laser Induced Breakdown Spectroscopy (LIBS). From these spectra, we were able to readily identify all elements of interest (B, Si, Ca, Fe, Mg, Na, Sr, Al). The high signal-to-background signals achieved suggest that data from the sensor can be used to determine elemental concentrations, either through calibration curves or using ERCo's calibrationless method. ERCo's technology fits in well with DOE's Glass Industry Technology Roadmap which emphasizes the need for accurate process and feedstock sensors. Listed first under technological barriers to increased production efficiency is the 'Inability to accurately measure and control the production process'. A large-scale glass melting furnace, developed by SenCer Inc. of Penn Yan, NY was installed in ERCo's laboratory to ensure that a large enough quantity of glass could be melted and held at temperature in the presence of the water-cooled laser sensor without solidifying the glass.

  1. In situ method for real time measurement of dielectric film thickness in plasmas

    SciTech Connect

    Jang, Sung-Ho; Kim, Gun-Ho; Chung, Chin-Wook

    2010-01-15

    An in situ thickness measurement method of dielectric films (dual frequency method) was developed, and the thicknesses were measured in an inductively coupled plasma. This method uses a small ac bias voltage with two frequencies for thickness measurement. The dielectric thickness is obtained from measuring the amplitudes of the two frequency ac currents through a sensor, as well as using an equivalent circuit model describing impedance of the dielectric film and the plasma sheath. In the experiment, the thicknesses of Al{sub 2}O{sub 3} film could be accurately measured in real time. To check the measurement reliability, the dual frequency method was compared with reflection spectrophotometry as a technique for optical thickness diagnostics. It was found that the dual frequency method agrees closely with reflection spectrophotometry at various rf powers and pressures. In addition, this method is very simple and can be installed anywhere in plasma reactors, in contrast with optical methods; therefore, it is expected to be applied to in situ surface diagnostics for various processing plasmas.

  2. Method and apparatus for real-time measurement of fuel gas compositions and heating values

    DOEpatents

    Zelepouga, Serguei; Pratapas, John M.; Saveliev, Alexei V.; Jangale, Vilas V.

    2016-03-22

    An exemplary embodiment can be an apparatus for real-time, in situ measurement of gas compositions and heating values. The apparatus includes a near infrared sensor for measuring concentrations of hydrocarbons and carbon dioxide, a mid infrared sensor for measuring concentrations of carbon monoxide and a semiconductor based sensor for measuring concentrations of hydrogen gas. A data processor having a computer program for reducing the effects of cross-sensitivities of the sensors to components other than target components of the sensors is also included. Also provided are corresponding or associated methods for real-time, in situ determination of a composition and heating value of a fuel gas.

  3. Real-time remote detection and measurement for airborne imaging spectroscopy: a case study with methane

    NASA Astrophysics Data System (ADS)

    Thompson, D. R.; Leifer, I.; Bovensmann, H.; Eastwood, M.; Fladeland, M.; Frankenberg, C.; Gerilowski, K.; Green, R. O.; Kratwurst, S.; Krings, T.; Luna, B.; Thorpe, A. K.

    2015-06-01

    Localized anthropogenic sources of atmospheric CH4 are highly uncertain and temporally variable. Airborne remote measurement is an effective method to detect and quantify these emissions. In a campaign context, the science yield can be dramatically increased by real-time retrievals that allow operators to coordinate multiple measurements of the most active areas. This can improve science outcomes for both single- and multiple-platform missions. We describe a case study of the NASA/ESA CO2 and Methane Experiment (COMEX) campaign in California during June and August/September 2014. COMEX was a multi-platform campaign to measure CH4 plumes released from anthropogenic sources including oil and gas infrastructure. We discuss principles for real-time spectral signature detection and measurement, and report performance on the NASA Next Generation Airborne Visible Infrared Spectrometer (AVIRIS-NG). AVIRIS-NG successfully detected CH4 plumes in real-time at Gb s-1 data rates, characterizing fugitive releases in concert with other in situ and remote instruments. The teams used these real-time CH4 detections to coordinate measurements across multiple platforms, including airborne in situ, airborne non-imaging remote sensing, and ground-based in situ instruments. To our knowledge this is the first reported use of real-time trace gas signature detection in an airborne science campaign, and presages many future applications.

  4. Development and Validation of a Highly Accurate Quantitative Real-Time PCR Assay for Diagnosis of Bacterial Vaginosis.

    PubMed

    Hilbert, David W; Smith, William L; Chadwick, Sean G; Toner, Geoffrey; Mordechai, Eli; Adelson, Martin E; Aguin, Tina J; Sobel, Jack D; Gygax, Scott E

    2016-04-01

    Bacterial vaginosis (BV) is the most common gynecological infection in the United States. Diagnosis based on Amsel's criteria can be challenging and can be aided by laboratory-based testing. A standard method for diagnosis in research studies is enumeration of bacterial morphotypes of a Gram-stained vaginal smear (i.e., Nugent scoring). However, this technique is subjective, requires specialized training, and is not widely available. Therefore, a highly accurate molecular assay for the diagnosis of BV would be of great utility. We analyzed 385 vaginal specimens collected prospectively from subjects who were evaluated for BV by clinical signs and Nugent scoring. We analyzed quantitative real-time PCR (qPCR) assays on DNA extracted from these specimens to quantify nine organisms associated with vaginal health or disease:Gardnerella vaginalis,Atopobium vaginae, BV-associated bacteria 2 (BVAB2, an uncultured member of the orderClostridiales),Megasphaeraphylotype 1 or 2,Lactobacillus iners,Lactobacillus crispatus,Lactobacillus gasseri, andLactobacillus jensenii We generated a logistic regression model that identifiedG. vaginalis,A. vaginae, andMegasphaeraphylotypes 1 and 2 as the organisms for which quantification provided the most accurate diagnosis of symptomatic BV, as defined by Amsel's criteria and Nugent scoring, with 92% sensitivity, 95% specificity, 94% positive predictive value, and 94% negative predictive value. The inclusion ofLactobacillusspp. did not contribute sufficiently to the quantitative model for symptomatic BV detection. This molecular assay is a highly accurate laboratory tool to assist in the diagnosis of symptomatic BV. PMID:26818677

  5. An optical real-time 3D measurement for analysis of facial shape and movement

    NASA Astrophysics Data System (ADS)

    Zhang, Qican; Su, Xianyu; Chen, Wenjing; Cao, Yiping; Xiang, Liqun

    2003-12-01

    Optical non-contact 3-D shape measurement provides a novel and useful tool for analysis of facial shape and movement in presurgical and postsurgical regular check. In this article we present a system, which allows a precise 3-D visualization of the patient's facial before and after craniofacial surgery. We discussed, in this paper, the real time 3-D image capture, processing and the 3-D phase unwrapping method to recover complex shape deformation when the movement of the mouth. The result of real-time measurement for facial shape and movement will be helpful for the more ideal effect in plastic surgery.

  6. Real-time measurements of the largest Lyapunov exponent in optical fields

    NASA Astrophysics Data System (ADS)

    Gavrylyak, M. S.; Maksimyak, P. P.

    2012-01-01

    An analog interference method for measuring the largest Lyapunov exponent in optical fields generated by scattering objects and mediums is proposed. The method is used to make a device for high-speed real time transverse correlation function optical fields measurement.

  7. Real-time measurements of the largest Lyapunov exponent in optical fields

    NASA Astrophysics Data System (ADS)

    Gavrylyak, M. S.; Maksimyak, P. P.

    2011-09-01

    An analog interference method for measuring the largest Lyapunov exponent in optical fields generated by scattering objects and mediums is proposed. The method is used to make a device for high-speed real time transverse correlation function optical fields measurement.

  8. High-resolution, real-time simultaneous 3D surface geometry and temperature measurement.

    PubMed

    An, Yatong; Zhang, Song

    2016-06-27

    This paper presents a method to simultaneously measure three-dimensional (3D) surface geometry and temperature in real time. Specifically, we developed 1) a holistic approach to calibrate both a structured light system and a thermal camera under exactly the same world coordinate system even though these two sensors do not share the same wavelength; and 2) a computational framework to determine the sub-pixel corresponding temperature for each 3D point as well as discard those occluded points. Since the thermal 2D imaging and 3D visible imaging systems do not share the same spectrum of light, they can perform sensing simultaneously in real time: we developed a hardware system that can achieve real-time 3D geometry and temperature measurement at 26 Hz with 768 × 960 points per frame. PMID:27410608

  9. Real-time MSE measurements for current profile control on KSTAR.

    PubMed

    De Bock, M F M; Aussems, D; Huijgen, R; Scheffer, M; Chung, J

    2012-10-01

    To step up from current day fusion experiments to power producing fusion reactors, it is necessary to control long pulse, burning plasmas. Stability and confinement properties of tokamak fusion reactors are determined by the current or q profile. In order to control the q profile, it is necessary to measure it in real-time. A real-time motional Stark effect diagnostic is being developed at Korean Superconducting Tokamak for Advanced Research for this purpose. This paper focuses on 3 topics important for real-time measurements: minimize the use of ad hoc parameters, minimize external influences and a robust and fast analysis algorithm. Specifically, we have looked into extracting the retardance of the photo-elastic modulators from the signal itself, minimizing the influence of overlapping beam spectra by optimizing the optical filter design and a multi-channel, multiharmonic phase locking algorithm. PMID:23126864

  10. Real-time phase measurement of optical vortices based on pixelated micropolarizer array.

    PubMed

    Zhang, Zhigang; Dong, Fengliang; Qian, Kemao; Zhang, Qingchuan; Chu, Weiguo; Zhang, Yuntian; Ma, Xuan; Wu, Xiaoping

    2015-08-10

    The special spiral phase structure of an optical vortex leads to an intriguing study in modern singular optics. This paper proposes a real-time phase measurement method of vortex beam based on pixelated micropolarizer array (PMA). Four phase-shifting fringe images can be obtained from a single interference image, thus the vortex beam phase can be obtained in real-time. The proposed method can achieve full-field phase measurement of the vortex beam with the advantages of lower computation and vibration resistance. In the experiments, the typical phases of vortex with different topological charges are loaded on a spatial light modulator (SLM) to generate diffraction vortex beam, and the phase distribution of vortex beam is obtained in real-time, which confirm the robustness of this method. This method is of great significance in promoting the study of optical vortices. PMID:26367904

  11. Real-time MSE measurements for current profile control on KSTAR

    SciTech Connect

    De Bock, M. F. M.; Aussems, D.; Huijgen, R.; Scheffer, M.; Chung, J.

    2012-10-15

    To step up from current day fusion experiments to power producing fusion reactors, it is necessary to control long pulse, burning plasmas. Stability and confinement properties of tokamak fusion reactors are determined by the current or q profile. In order to control the q profile, it is necessary to measure it in real-time. A real-time motional Stark effect diagnostic is being developed at Korean Superconducting Tokamak for Advanced Research for this purpose. This paper focuses on 3 topics important for real-time measurements: minimize the use of ad hoc parameters, minimize external influences and a robust and fast analysis algorithm. Specifically, we have looked into extracting the retardance of the photo-elastic modulators from the signal itself, minimizing the influence of overlapping beam spectra by optimizing the optical filter design and a multi-channel, multiharmonic phase locking algorithm.

  12. [Measurement of left atrial and ventricular volumes in real-time 3D echocardiography. Validation by nuclear magnetic resonance

    NASA Technical Reports Server (NTRS)

    Bauer, F.; Shiota, T.; Qin, J. X.; White, R. D.; Thomas, J. D.

    2001-01-01

    The measurement of the left ventricular ejection fraction is important for the evaluation of cardiomyopathy and depends on the measurement of left ventricular volumes. There are no existing conventional echocardiographic means of measuring the true left atrial and ventricular volumes without mathematical approximations. The aim of this study was to test anew real time 3-dimensional echocardiographic system of calculating left atrial and ventricular volumes in 40 patients after in vitro validation. The volumes of the left atrium and ventricle acquired from real time 3-D echocardiography in the apical view, were calculated in 7 sections parallel to the surface of the probe and compared with atrial (10 patients) and ventricular (30 patients) volumes calculated by nuclear magnetic resonance with the simpson method and with volumes of water in balloons placed in a cistern. Linear regression analysis showed an excellent correlation between the real volume of water in the balloons and volumes given in real time 3-dimensional echocardiography (y = 0.94x + 5.5, r = 0.99, p < 0.001, D = -10 +/- 4.5 ml). A good correlation was observed between real time 3-dimensional echocardiography and nuclear magnetic resonance for the measurement of left atrial and ventricular volumes (y = 0.95x - 10, r = 0.91, p < 0.001, D = -14.8 +/- 19.5 ml and y = 0.87x + 10, r = 0.98, P < 0.001, D = -8.3 +/- 18.7 ml, respectively. The authors conclude that real time three-dimensional echocardiography allows accurate measurement of left heart volumes underlying the clinical potential of this new 3-D method.

  13. Dielectric measurement method for real-time monitoring of initial hardening of backfill materials used for underground construction

    NASA Astrophysics Data System (ADS)

    Karlovšek, Jurij; Schwing, Moritz; Chen, Zhen; Wagner, Norman; Williams, David J.; Scheuermann, Alexander

    2016-04-01

    The broadband dielectric measurement method based on the vector network analysis technique, in combination with an open-ended coaxial probe, was applied to the determination of the dielectric relaxation behaviour of one- and two-component backfilling grout materials in the frequency range from 40 MHz to 2 GHz. The cement hydration process and the gelling of commercial grouts was monitored in real-time to investigate the application of non-destructive testing methods in the tunnelling industry. It was found that the time-dependent dielectric relaxation behaviour can accurately reveal the different stages of the hydration process and delineate the start of gel hardening. These measurement results demonstrate the practicability of the real-time dielectric measurement method to determine the broadband dielectric parameters of conventional backfill materials used in underground construction to determine construction integrity using non-destructive testing methods.

  14. In-situ real time measurements of net erosion rates of copper during hydrogen plasma exposure

    NASA Astrophysics Data System (ADS)

    Kesler, Leigh; Wright, Graham; Peterson, Ethan; Whyte, Dennis

    2013-10-01

    In order to properly understand the dynamics of net erosion/deposition in fusion reactors, such as tokamaks, a diagnostic measuring the real time rates of net erosion/deposition during plasma exposure is necessary. The DIONISOS experiment produces real time measurements of net erosion/deposition by using Rutherford backscattering spectroscopy (RBS) ion beam analysis simultaneously with plasma exposure from a helicon plasma source. This in-situ method improves on ex-situ weight loss measurements by allowing measurement of possible synergistic effects of high ion implantation rates and net erosion rate and by giving a real time response to changes in plasma parameters. Previous work has validated this new technique for measuring copper (Cu) erosion from helium (He) plasma ion bombardment. This technique is now extended to measure copper erosion due to deuterium and hydrogen plasma ion exposure. Targets used were a 1.5 μm Cu layer on an aluminum substrate. Cu layer thickness is tracked in real time using 1.2 MeV proton RBS. Measured erosion rates will be compared to results from literature and He erosion rates. Supported by US DoE award DE-SC00-02060.

  15. Accurate, Fast and Cost-Effective Diagnostic Test for Monosomy 1p36 Using Real-Time Quantitative PCR

    PubMed Central

    Cunha, Pricila da Silva; Pena, Heloisa B.; D'Angelo, Carla Sustek; Koiffmann, Celia P.; Rosenfeld, Jill A.; Shaffer, Lisa G.; Stofanko, Martin; Gonçalves-Dornelas, Higgor; Pena, Sérgio Danilo Junho

    2014-01-01

    Monosomy 1p36 is considered the most common subtelomeric deletion syndrome in humans and it accounts for 0.5–0.7% of all the cases of idiopathic intellectual disability. The molecular diagnosis is often made by microarray-based comparative genomic hybridization (aCGH), which has the drawback of being a high-cost technique. However, patients with classic monosomy 1p36 share some typical clinical characteristics that, together with its common prevalence, justify the development of a less expensive, targeted diagnostic method. In this study, we developed a simple, rapid, and inexpensive real-time quantitative PCR (qPCR) assay for targeted diagnosis of monosomy 1p36, easily accessible for low-budget laboratories in developing countries. For this, we have chosen two target genes which are deleted in the majority of patients with monosomy 1p36: PRKCZ and SKI. In total, 39 patients previously diagnosed with monosomy 1p36 by aCGH, fluorescent in situ hybridization (FISH), and/or multiplex ligation-dependent probe amplification (MLPA) all tested positive on our qPCR assay. By simultaneously using these two genes we have been able to detect 1p36 deletions with 100% sensitivity and 100% specificity. We conclude that qPCR of PRKCZ and SKI is a fast and accurate diagnostic test for monosomy 1p36, costing less than 10 US dollars in reagent costs. PMID:24839341

  16. Improved process control through real-time measurement of mineral content

    SciTech Connect

    Turler, Daniel; Karaca, Murat; Davis, William B.; Giauque, Robert D.; Hopkins, Deborah

    2001-11-02

    In a highly collaborative research and development project with mining and university partners, sensors and data-analysis tools are being developed for rock-mass characterization and real-time measurement of mineral content. Determining mineralogy prior to mucking in an open-pit mine is important for routing the material to the appropriate processing stream. A possible alternative to lab assay of dust and cuttings obtained from drill holes is continuous on-line sampling and real-time x-ray fluorescence (XRF) spectroscopy. Results presented demonstrate that statistical analyses combined with XRF data can be employed to identify minerals and, possibly, different rock types. The objective is to create a detailed three-dimensional mineralogical map in real time that would improve downstream process efficiency.

  17. Real-time measurements of a 40 Gb/s coherent system.

    PubMed

    Sun, Han; Wu, Kuang-Tsan; Roberts, Kim

    2008-01-21

    Continuous real-time measurements are shown from a coherent 40 Gb/s transmission system that uses Dual-Polarization Quadrature Phase Shift Keying (DP-QPSK) modulation. Digital compensation is used for dispersion and polarization effects, with little performance degradation created by 150 ps of rapidly varying 1st-order PMD. PMID:18542161

  18. Real-time remote detection and measurement for airborne imaging spectroscopy: a case study with methane

    NASA Astrophysics Data System (ADS)

    Thompson, D. R.; Leifer, I.; Bovensmann, H.; Eastwood, M.; Fladeland, M.; Frankenberg, C.; Gerilowski, K.; Green, R. O.; Kratwurst, S.; Krings, T.; Luna, B.; Thorpe, A. K.

    2015-10-01

    Localized anthropogenic sources of atmospheric CH4 are highly uncertain and temporally variable. Airborne remote measurement is an effective method to detect and quantify these emissions. In a campaign context, the science yield can be dramatically increased by real-time retrievals that allow operators to coordinate multiple measurements of the most active areas. This can improve science outcomes for both single- and multiple-platform missions. We describe a case study of the NASA/ESA CO2 and MEthane eXperiment (COMEX) campaign in California during June and August/September 2014. COMEX was a multi-platform campaign to measure CH4 plumes released from anthropogenic sources including oil and gas infrastructure. We discuss principles for real-time spectral signature detection and measurement, and report performance on the NASA Next Generation Airborne Visible Infrared Spectrometer (AVIRIS-NG). AVIRIS-NG successfully detected CH4 plumes in real-time at Gb s-1 data rates, characterizing fugitive releases in concert with other in situ and remote instruments. The teams used these real-time CH4 detections to coordinate measurements across multiple platforms, including airborne in situ, airborne non-imaging remote sensing, and ground-based in situ instruments. To our knowledge this is the first reported use of real-time trace-gas signature detection in an airborne science campaign, and presages many future applications. Post-analysis demonstrates matched filter methods providing noise-equivalent (1σ) detection sensitivity for 1.0 % CH4 column enhancements equal to 141 ppm m.

  19. Real-time automated thickness measurement of the in vivo human tympanic membrane using optical coherence tomography

    PubMed Central

    Hubler, Zita; Shemonski, Nathan D.; Shelton, Ryan L.; Monroy, Guillermo L.; Nolan, Ryan M.

    2015-01-01

    Background Otitis media (OM), an infection in the middle ear, is extremely common in the pediatric population. Current gold-standard methods for diagnosis include otoscopy for visualizing the surface features of the tympanic membrane (TM) and making qualitative assessments to determine middle ear content. OM typically presents as an acute infection, but can progress to chronic OM, and after numerous infections and antibiotic treatments over the course of many months, this disease is often treated by surgically inserting small tubes in the TM to relieve pressure, enable drainage, and provide aeration to the middle ear. Diagnosis and monitoring of OM is critical for successful management, but remains largely qualitative. Methods We have developed an optical coherence tomography (OCT) system for high-resolution, depth-resolved, cross-sectional imaging of the TM and middle ear content, and for the quantitative assessment of in vivo TM thickness including the presence or absence of a middle ear biofilm. A novel algorithm was developed and demonstrated for automatic, real-time, and accurate measurement of TM thickness to aid in the diagnosis and monitoring of OM and other middle ear conditions. The segmentation algorithm applies a Hough transform to the OCT image data to determine the boundaries of the TM to calculate thickness. Results The use of OCT and this segmentation algorithm is demonstrated first on layered phantoms and then during real-time acquisition of in vivo OCT from humans. For the layered phantoms, measured thicknesses varied by approximately 5 µm over time in the presence of large axial and rotational motion. In vivo data also demonstrated differences in thicknesses both spatially on a single TM, and across normal, acute, and chronic OM cases. Conclusions Real-time segmentation and thickness measurements of image data from both healthy subjects and those with acute and chronic OM demonstrate the use of OCT and this algorithm as a robust, quantitative

  20. Real-time estimation of plasma insulin concentration from continuous glucose monitor measurements.

    PubMed

    de Pereda, Diego; Romero-Vivo, Sergio; Ricarte, Beatriz; Rossetti, Paolo; Ampudia-Blasco, Francisco Javier; Bondia, Jorge

    2016-01-01

    Continuous glucose monitors can measure interstitial glucose concentration in real time for closed-loop glucose control systems, known as artificial pancreas. These control systems use an insulin feedback to maintain plasma glucose concentration within a narrow and safe range, and thus to avoid health complications. As it is not possible to measure plasma insulin concentration in real time, insulin models have been used in literature to estimate them. Nevertheless, the significant inter- and intra-patient variability of insulin absorption jeopardizes the accuracy of these estimations. In order to reduce these limitations, our objective is to perform a real-time estimation of plasma insulin concentration from continuous glucose monitoring (CGM). Hovorka's glucose-insulin model has been incorporated in an extended Kalman filter in which different selected time-variant model parameters have been considered as extended states. The observability of the original Hovorka's model and of several extended models has been evaluated by their Lie derivatives. We have evaluated this methodology with an in-silico study with 100 patients with Type 1 diabetes during 25 h. Furthermore, it has been also validated using clinical data from 12 insulin pump patients with Type 1 diabetes who underwent four mixed meal studies. Real-time insulin estimations have been compared to plasma insulin measurements to assess performance showing the validity of the methodology here used in comparison with that formerly used for insulin models. Hence, real-time estimations for plasma insulin concentration based on subcutaneous glucose monitoring can be beneficial for increasing the efficiency of control algorithms for the artificial pancreas. PMID:26343364

  1. Real-time emission factor measurements of isocyanic acid from light duty gasoline vehicles

    NASA Astrophysics Data System (ADS)

    Brady, J.; Crisp, T. A.; Collier, S.; Kuwayama, T.; Zhang, Q.; Kleeman, M.; Bertram, T. H.

    2013-12-01

    Recent work has demonstrated the potential for vehicle based anthropogenic sources of the carcinogen isocyanic acid (HNCO) in urban environments. Although emission factors for HNCO have recently been measured for light duty diesel vehicles, light duty gasoline vehicles are not well characterized. Here we will present real-time emission factor measurements of HNCO for light duty gasoline vehicles measured at the California Air Resource Board's Haagen-Smit Laboratory in September of 2011 driven on a chassis dynamometer using the California Unified Driving Cycle. Emission factors for HNCO were determined for eight light duty gasoline vehicles utilizing a fast response chemical ionization time-of-flight mass spectrometer and simultaneous real-time measurements of CO, CO2, and NOx. We will discuss the potential production mechanism for HNCO by light duty gasoline vehicles as well as the potential drive cycle dependency of HNCO production.

  2. The emergence of flow cytometry for sensitive, real-time measurements of molecular interactions

    SciTech Connect

    Nolan, J.P.; Sklar, L.A. |

    1998-07-01

    The analysis of macromolecular interactions is an essential element of biomedical research. Flow cytometry is uniquely capable of making sensitive and quantitative measurements of molecular interactions. These measurements can be made in real time with subsecond kinetic resolution using purified biomolecules or living cells. Combined with automated sample handling, these features make flow cytometry a versatile and robust technology for the analysis of molecular interactions.

  3. Digital Holography for in Situ Real-Time Measurement of Plasma-Facing-Component Erosion

    SciTech Connect

    ThomasJr., C. E.; Granstedt, E. M.; Biewer, Theodore M; Baylor, Larry R; Combs, Stephen Kirk; Meitner, Steven J; Hillis, Donald Lee; Majeski, R.; Kaita, R.

    2014-01-01

    In situ, real time measurement of net plasma-facing-component (PFC) erosion/deposition in a real plasma device is challenging due to the need for good spatial and temporal resolution, sufficient sensitivity, and immunity to fringe-jump errors. Design of a high-sensitivity, potentially high-speed, dual-wavelength CO2 laser digital holography system (nominally immune to fringe jumps) for PFC erosion measurement is discussed.

  4. Accurate and in situ monitoring of bacterial concentration using a real time all-fibre spectroscopic device

    NASA Astrophysics Data System (ADS)

    Tao, W.; McGoverin, C.; Lydiard, S.; Song, Y.; Cheng, M.; Swift, S.; Singhal, N.; Vanholsbeeck, F.

    2015-07-01

    Accurate in situ monitoring of bacterial transport is important for increased understanding and improvement of bioremediation processes where microorganisms convert toxic compounds to more benign compounds. Bioremediation methods have become the preferred mechanism for the rehabilitation of hard to reach contaminated environments. In this study, we have used fluorescence spectroscopy to monitor the movement of fluorescently labelled bacteria (Rhodococcus erythropolis and Pseudomonas putida) within a bench-top column filled with a porous medium. In situ fluorescence measurements made using a fibre optic based instrument (`optrode') were compared to ex situ measurements made using a plate reader. In situ monitoring using this fibre optic based instrument is a promising alternative to ex situ measurements as the initial flow of bacteria is reliably observed. However, a greater understanding of the effect of the porous medium on fluorescence measurements is required to develop an accurate calibration for bacterial concentration based in situ measurements.

  5. Real-time emission factor measurements of isocyanic acid from light duty gasoline vehicles.

    PubMed

    Brady, James M; Crisp, Timia A; Collier, Sonya; Kuwayama, Toshihiro; Forestieri, Sara D; Perraud, Véronique; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D; Bertram, Timothy H

    2014-10-01

    Exposure to gas-phase isocyanic acid (HNCO) has been previously shown to be associated with the development of atherosclerosis, cataracts and rheumatoid arthritis. As such, accurate emission inventories for HNCO are critical for modeling the spatial and temporal distribution of HNCO on a regional and global scale. To date, HNCO emission rates from light duty gasoline vehicles, operated under driving conditions, have not been determined. Here, we present the first measurements of real-time emission factors of isocyanic acid from a fleet of eight light duty gasoline-powered vehicles (LDGVs) tested on a chassis dynamometer using the Unified Driving Cycle (UC) at the California Air Resources Board (CARB) Haagen-Smit test facility, all of which were equipped with three-way catalytic converters. HNCO emissions were observed from all vehicles, in contrast to the idealized laboratory measurements. We report the tested fleet averaged HNCO emission factors, which depend strongly on the phase of the drive cycle; ranging from 0.46 ± 0.13 mg kg fuel(-1) during engine start to 1.70 ± 1.77 mg kg fuel(-1) during hard acceleration after the engine and catalytic converter were warm. The tested eight-car fleet average fuel based HNCO emission factor was 0.91 ± 0.58 mg kg fuel(-1), within the range previously estimated for light duty diesel-powered vehicles (0.21-3.96 mg kg fuel(-1)). Our results suggest that HNCO emissions from LDGVs represent a significant emission source in urban areas that should be accounted for in global and regional models. PMID:25198906

  6. The "dual-spot" Aethalometer: an improved measurement of aerosol black carbon with real-time loading compensation

    NASA Astrophysics Data System (ADS)

    Drinovec, L.; Močnik, G.; Zotter, P.; Prévôt, A. S. H.; Ruckstuhl, C.; Coz, E.; Rupakheti, M.; Sciare, J.; Müller, T.; Wiedensohler, A.; Hansen, A. D. A.

    2015-05-01

    Aerosol black carbon is a unique primary tracer for combustion emissions. It affects the optical properties of the atmosphere and is recognized as the second most important anthropogenic forcing agent for climate change. It is the primary tracer for adverse health effects caused by air pollution. For the accurate determination of mass equivalent black carbon concentrations in the air and for source apportionment of the concentrations, optical measurements by filter-based absorption photometers must take into account the "filter loading effect". We present a new real-time loading effect compensation algorithm based on a two parallel spot measurement of optical absorption. This algorithm has been incorporated into the new Aethalometer model AE33. Intercomparison studies show excellent reproducibility of the AE33 measurements and very good agreement with post-processed data obtained using earlier Aethalometer models and other filter-based absorption photometers. The real-time loading effect compensation algorithm provides the high-quality data necessary for real-time source apportionment and for determination of the temporal variation of the compensation parameter k.

  7. Real-time gas density measurement using a ring cavity terahertz parametric oscillator

    NASA Astrophysics Data System (ADS)

    Ohno, S.; Guo, R.; Minamide, H.; Ito, H.

    2007-05-01

    We carried out real-time measurement of gas density using monochromatic terahertz waves. The THz-wave absorbance is useful to measure the density of a gas having a characteristic spectrum in the THz region. We used the ring cavity THz-wave parametric oscillator (ring-TPO) as a monochromatic tunable THz-wave source. One can change the oscillation frequency of ring-TPO with a rotating galvano mirror forming the ring cavity. The frequency can be changed by synchronization with a repeating pump-pulse of 500 Hz. We demonstrated real-time measurement of the gas density in R-22, which had some spectral structure in THz frequency region. The gas density in the sample cell was changed by controlling the pressure to lower than 1 atm. When the gas density in the cell was the most tenuous, the maximum sensitivity was about 5%, which was limited by the fluctuation of THz-wave intensity.

  8. Real-time locating and speed measurement of fibre fuse using optical frequency-domain reflectometry.

    PubMed

    Jiang, Shoulin; Ma, Lin; Fan, Xinyu; Wang, Bin; He, Zuyuan

    2016-01-01

    We propose and experimentally demonstrate real-time locating and speed measurement of fibre fuse by analysing the Doppler shift of reflected light using optical frequency-domain reflectometry (OFDR). Our method can detect the start of a fibre fuse within 200 ms which is equivalent to a propagation distance of about 10 cm in standard single-mode fibre. We successfully measured instantaneous speed of propagating fibre fuses and observed their subtle fluctuation owing to the laser power instability. The resolution achieved for speed measurement in our demonstration is 1 × 10(-3) m/s. We studied the fibre fuse propagation speed dependence on the launched power in different fibres. Our method is promising for both real time fibre fuse monitoring and future studies on its propagation and termination. PMID:27146550

  9. Real-time locating and speed measurement of fibre fuse using optical frequency-domain reflectometry

    NASA Astrophysics Data System (ADS)

    Jiang, Shoulin; Ma, Lin; Fan, Xinyu; Wang, Bin; He, Zuyuan

    2016-05-01

    We propose and experimentally demonstrate real-time locating and speed measurement of fibre fuse by analysing the Doppler shift of reflected light using optical frequency-domain reflectometry (OFDR). Our method can detect the start of a fibre fuse within 200 ms which is equivalent to a propagation distance of about 10 cm in standard single-mode fibre. We successfully measured instantaneous speed of propagating fibre fuses and observed their subtle fluctuation owing to the laser power instability. The resolution achieved for speed measurement in our demonstration is 1 × 10‑3 m/s. We studied the fibre fuse propagation speed dependence on the launched power in different fibres. Our method is promising for both real time fibre fuse monitoring and future studies on its propagation and termination.

  10. LANL's near-real-time measurement control bolt-on to LANMAS

    SciTech Connect

    Hicks, Ruel D; Boyle, Caroline M

    2010-01-01

    Los Alamos National Laboratory (LANL) has created a near-real-time Measurement Control Program (MCP) that integrates with Local Area Network Material Accounting System (LANMAS). The program was designed to take the place of an aging accounting system at LANL which incorporated the measurement control. LANL's Material Control and Accountability (MC&A) group developed many bolt-on features to enhance LANMAS called LAM CAS (Los Alamos Material Control and Accounting System), one of those bolt-on enhancements was to develop the MCP to replace the previous version. MCP was developed with the multiple end-user groups in mind by creating a near-real-time system that was user friendly, provided access controls, and account status of the measurement control systems.

  11. Real-time locating and speed measurement of fibre fuse using optical frequency-domain reflectometry

    PubMed Central

    Jiang, Shoulin; Ma, Lin; Fan, Xinyu; Wang, Bin; He, Zuyuan

    2016-01-01

    We propose and experimentally demonstrate real-time locating and speed measurement of fibre fuse by analysing the Doppler shift of reflected light using optical frequency-domain reflectometry (OFDR). Our method can detect the start of a fibre fuse within 200 ms which is equivalent to a propagation distance of about 10 cm in standard single-mode fibre. We successfully measured instantaneous speed of propagating fibre fuses and observed their subtle fluctuation owing to the laser power instability. The resolution achieved for speed measurement in our demonstration is 1 × 10−3 m/s. We studied the fibre fuse propagation speed dependence on the launched power in different fibres. Our method is promising for both real time fibre fuse monitoring and future studies on its propagation and termination. PMID:27146550

  12. Assimilating Electron Density Profiles Measured by the Real Time Global Ionospheric Radio Observatory - GIRO

    NASA Astrophysics Data System (ADS)

    Reinisch, B. W.; Galkin, I. A.

    2009-04-01

    Operational applications of ionospheric models, whether they are first principles or data-driven models, rely on the accuracy of the models during quiet and disturbed conditions. Of course models can correctly describe ionospheric weather only if they assimilate measured ionospheric characteristics and electron density profiles (EDPs). For the "assimilating model" to make correct predictions, the measurements in turn must be accurate and reliable. Ionosondes provide the most accurate vertical EDPs at the site locations but do not cover all parts of the globe. Ionogram-derived EDPs have become the ground truth reference for ionospheric specification, presenting the unrivaled accuracy of the data on continuous demand for validation of alternative ionospheric techniques, including radio occultation, ultraviolet, and tomography. In recent years the digisonde network of ionosondes has grown to eighty stations and is expected to expand to more than 100 stations in the next couple of years. The new Digisonde-4D is running the Automatic Real Time Ionogram Scaler with True height inversion, ARTIST-5. The ARTIST-5 autoscaling program now calculates the EDPs together with density uncertainty limits at each height, making the data products suitable for ingestion in assimilative ionospheric models. In order to specify uncertainty at each height, two boundary profiles, inner and outer, are determined. The inner and outer boundaries reflect the uncertainties of the critical frequencies of each layer, the internal uncertainty of the starting height of the profile, and the uncertainties of the E valley model representation. The actual uncertainties are calculated from a cumulative difference characteristic representing a mismatch between automatically and manually scaled parameters (i.e., foF2, foF1) for the same ionogram. The cumulative differences are determined from statistical analysis of a large amount of ionograms for a specific station. The characteristics of interest are

  13. Real-time electron density measurements from Cotton-Mouton effect in JET machine

    SciTech Connect

    Brombin, M.; Boboc, A.; Zabeo, L.

    2008-10-15

    Real-time density profile measurements are essential for advanced fusion tokamak operation and interferometry is a proven method for this task. Nevertheless, as a consequence of edge localized modes, pellet injections, fast density increases, or disruptions, the interferometer is subject to fringe jumps, which produce loss of the signal preventing reliable use of the measured density in a real-time feedback controller. An alternative method to measure the density is polarimetry based on the Cotton-Mouton effect, which is proportional to the line-integrated electron density. A new analysis approach has been implemented and tested to verify the reliability of the Cotton-Mouton measurements for a wide range of plasma parameters and to compare the density evaluated from polarimetry with that from interferometry. The density measurements based on polarimetry are going to be integrated in the real-time control system of JET since the difference with the interferometry is within one fringe for more than 90% of the cases.

  14. Real-Time Inhibitor Recession Measurements in the Space Shuttle Reusable Solid Rocket Motors

    NASA Technical Reports Server (NTRS)

    McWhorter, Bruce B.; Ewing, Mark E.; McCool, Alex (Technical Monitor)

    2001-01-01

    Real-time char line recession measurements were made on propellant inhibitors of the Space Shuttle Reusable Solid Rocket Motor (RSRM). The RSRM FSM-8 static test motor propellant inhibitors (composed of a rubber insulation material) were successfully instrumented with eroding potentiometers and thermocouples. The data was used to establish inhibitor recession versus time relationships. Normally, pre-fire and post-fire insulation thickness measurements establish the thermal performance of an ablating insulation material. However, post-fire inhibitor decomposition and recession measurements are complicated by the fact that most of the inhibitor is back during motor operation. It is therefore a difficult task to evaluate the thermal protection offered by the inhibitor material. Real-time measurements would help this task. The instrumentation program for this static test motor marks the first time that real-time inhibitors. This report presents that data for the center and aft field joint forward facing inhibitors. The data was primarily used to measure char line recession of the forward face of the inhibitors which provides inhibitor thickness reduction versus time data. The data was also used to estimate the inhibitor height versus time relationship during motor operation.

  15. 3D real-time measurement system of seam with laser

    NASA Astrophysics Data System (ADS)

    Huang, Min-shuang; Huang, Jun-fen

    2014-02-01

    3-D Real-time Measurement System of seam outline based on Moiré Projection is proposed and designed. The system is composed of LD, grating, CCD, video A/D, FPGA, DSP and an output interface. The principle and hardware makeup of high-speed and real-time image processing circuit based on a Digital Signal Processor (DSP) and a Field Programmable Gate Array (FPGA) are introduced. Noise generation mechanism in poor welding field conditions is analyzed when Moiré stripes are projected on a welding workpiece surface. Median filter is adopted to smooth the acquired original laser image of seam, and then measurement results of a 3-D outline image of weld groove are provided.

  16. Real-time transverse force sensing using fiber Bragg grating through direct Stokes parameters measurement.

    PubMed

    Su, Yang; Zhu, Yong; Zhang, Baofu; Zhou, Hua

    2015-12-14

    Characteristics of a fiber Bragg grating (FBG) transverse force sensor based on Stokes parameters are presented. Real-time force measurement is achieved through direct measurement of the Stokes parameters at single wavelength. A proportional relationship and linear fit are found between Stokes parameters and applied force. The sensitivity and dynamic range dependence on the state of polarization (SOP) of the incident light is investigated theoretically and experimentally. A maximum sensitivity of 0.037/N is experimentally achieved and it can be improved further by adjusting the incident SOP. This design significantly reduces system complexity and improves data processing speed, which has great practical value in real-time FBG sensing applications. PMID:26699020

  17. Benchmarking flood models from space in near real-time: accommodating SRTM height measurement errors with low resolution flood imagery

    NASA Astrophysics Data System (ADS)

    Schumann, G.; di Baldassarre, G.; Alsdorf, D.; Bates, P. D.

    2009-04-01

    In February 2000, the Shuttle Radar Topography Mission (SRTM) measured the elevation of most of the Earth's surface with spatially continuous sampling and an absolute vertical accuracy greater than 9 m. The vertical error has been shown to change with topographic complexity, being less important over flat terrain. This allows water surface slopes to be measured and associated discharge volumes to be estimated for open channels in large basins, such as the Amazon. Building on these capabilities, this paper demonstrates that near real-time coarse resolution radar imagery of a recent flood event on a 98 km reach of the River Po (Northern Italy) combined with SRTM terrain height data leads to a water slope remarkably similar to that derived by combining the radar image with highly accurate airborne laser altimetry. Moreover, it is shown that this space-borne flood wave approximation compares well to a hydraulic model and thus allows the performance of the latter, calibrated on a previous event, to be assessed when applied to an event of different magnitude in near real-time. These results are not only of great importance to real-time flood management and flood forecasting but also support the upcoming Surface Water and Ocean Topography (SWOT) mission that will routinely provide water levels and slopes with higher precision around the globe.

  18. Rapid assessment of Cascadia tsunamis from real-time PANGA GPS crustal deformation measurements

    NASA Astrophysics Data System (ADS)

    Melbourne, T. I.; Santillan, M.; Miner, A.; Webb, F.

    2008-12-01

    Cascadia's natural hazards include earthquakes, tsunamis, volcanic eruptions, landslides, and tectonic subsidence along its coasts and inland waterways exacerbated by sea-level rise. The Pacific Northwest Geodetic Array, now comprised of nearly 200 continuous GPS receivers, has been deployed over the last two decades to focus exclusively on mitigating these hazards. In addition, over 150 receivers of the EarthScope Plate Boundary Observatory have also been installed in Cascadia, thus comprising a combined network of over 350 instruments. Of the 200 PANGA stations, nearly 140 are high-rate, real-time telemetered receivers mounted on CWU-built, tectonics-grade monuments. These stations straddle active crustal faults, volcanoes and landslides, they span the megathrust forearc and tsunamigenic regions along the Pacific coast, and they monitor ageing man-made structures such as dams, levees and elevated freeways. All data from this array, currently at over 140 stations, is streamed in real-time into CWU where it is archived and processed with JPL's GIPSY software. In 2005 PANGA received support from NASA, NSF and the USGS to implement real-time processing in support of mitigating Cascadia's natural hazards. We have implemented Trimble Navigation's proprietary RTK software and network monitoring software on all 140 stations, and specific parameter estimation routines on a subset of these stations. Pending available funding, we are also working to implement processing of this data with the RTGipsy software, which produces position time series within a global, not local, reference frame. We are currently writing applications that will facilitate rapid recovery during and after a large seismic event, tsunami, or volcanic eruption. These applications are focused on: - Inverting GPS deformation measurements for earthquake fault location, size, and slip distribution; - Using slip distributions to predict tsunami magnitude and run-up estimates; - Real-time monitoring of

  19. Analytical real-time measurement of a three-dimensional weld pool surface

    NASA Astrophysics Data System (ADS)

    Zhang, WeiJie; Wang, XueWu; Zhang, YuMing

    2013-11-01

    The ability to observe and measure weld pool surfaces in real-time is the core of the foundation for next generation intelligent welding that can partially imitate skilled welders who observe the weld pool to acquire information on the welding process. This study aims at the real-time measurement of the specular three-dimensional (3D) weld pool surface under a strong arc in gas tungsten arc welding (GTAW). An innovative vision system is utilized in this study to project a dot-matrix laser pattern on the specular weld pool surface. Its reflection from the surface is intercepted at a distance from the arc by a diffuse plane. The intercepted laser dots illuminate this plane producing an image showing the reflection pattern. The deformation of this reflection pattern from the projected pattern (e.g. the dot matrix) is used to derive the 3D shape of the reflection surface, i.e., the weld pool surface. Based on careful analysis, the underlying reconstruction problem is formulated mathematically. An analytic solution is proposed to solve this formulated problem resulting in the weld pool surface being reconstructed on average in 3.04 ms during welding experiments. A vision-based monitoring system is thus established to measure the weld pool surface in GTAW in real-time. In order to verify the effectiveness of the proposed reconstruction algorithm, first numerical simulation is conducted. The proposed algorithm is then tested on a spherical convex mirror with a priori knowledge of its geometry. The detailed analysis of the measurement error validates the accuracy of the proposed algorithm. Results from the real-time experiments verify the robustness of the proposed reconstruction algorithm.

  20. Real-time full bandwidth measurement of spectral noise in supercontinuum generation

    PubMed Central

    Wetzel, B.; Stefani, A.; Larger, L.; Lacourt, P. A.; Merolla, J. M.; Sylvestre, T.; Kudlinski, A.; Mussot, A.; Genty, G.; Dias, F.; Dudley, J. M.

    2012-01-01

    The ability to measure real-time fluctuations of ultrashort pulses propagating in optical fiber has provided significant insights into fundamental dynamical effects such as modulation instability and the formation of frequency-shifting rogue wave solitons. We report here a detailed study of real-time fluctuations across the full bandwidth of a fiber supercontinuum which directly reveals the significant variation in measured noise statistics across the spectrum, and which allows us to study correlations between widely separated spectral components. For two different propagation distances corresponding to the onset phase of spectral broadening and the fully-developed supercontinuum, we measure real time noise across the supercontinuum bandwidth, and we quantify the supercontinuum noise using statistical higher-order moments and a frequency-dependent intensity correlation map. We identify correlated spectral regions within the supercontinuum associated with simultaneous sideband generation, as well as signatures of pump depletion and soliton-like pump dynamics. Experimental results are in excellent agreement with simulations. PMID:23193436

  1. Real-time measurement of dust in the workplace using video exposure monitoring: Farming to pharmaceuticals

    NASA Astrophysics Data System (ADS)

    Walsh, P. T.; Forth, A. R.; Clark, R. D. R.; Dowker, K. P.; Thorpe, A.

    2009-02-01

    Real-time, photometric, portable dust monitors have been employed for video exposure monitoring (VEM) to measure and highlight dust levels generated by work activities, illustrate dust control techniques, and demonstrate good practice. Two workplaces, presenting different challenges for measurement, were used to illustrate the capabilities of VEM: (a) poultry farming activities and (b) powder transfer operations in a pharmaceutical company. For the poultry farm work, the real-time monitors were calibrated with respect to the respirable and inhalable dust concentrations using cyclone and IOM reference samplers respectively. Different rankings of exposure for typical activities were found on the small farm studied here compared to previous exposure measurements at larger poultry farms: these were mainly attributed to the different scales of operation. Large variations in the ratios of respirable, inhalable and real-time monitor TWA concentrations of poultry farm dust for various activities were found. This has implications for the calibration of light-scattering dust monitors with respect to inhalable dust concentration. In the pharmaceutical application, the effectiveness of a curtain barrier for dust control when dispensing powder in a downflow booth was rapidly demonstrated.

  2. Development of a Capacitive Ice Sensor to Measure Ice Growth in Real Time

    PubMed Central

    Zhi, Xiang; Cho, Hyo Chang; Wang, Bo; Ahn, Cheol Hee; Moon, Hyeong Soon; Go, Jeung Sang

    2015-01-01

    This paper presents the development of the capacitive sensor to measure the growth of ice on a fuel pipe surface in real time. The ice sensor consists of pairs of electrodes to detect the change in capacitance and a thermocouple temperature sensor to examine the ice formation situation. In addition, an environmental chamber was specially designed to control the humidity and temperature to simulate the ice formation conditions. From the humidity, a water film is formed on the ice sensor, which results in an increase in capacitance. Ice nucleation occurs, followed by the rapid formation of frost ice that decreases the capacitance suddenly. The capacitance is saturated. The developed ice sensor explains the ice growth providing information about the icing temperature in real time. PMID:25808770

  3. Real-time data acquisition and control system for the measurement of motor and neural data.

    PubMed

    Bryant, Christopher L; Gandhi, Neeraj J

    2005-03-30

    This paper outlines a powerful, yet flexible real-time data acquisition and control system for use in the triggering and measurement of both analog and digital events. Built using the LabVIEW development architecture (version 7.1) and freely available, this system provides precisely timed auditory and visual stimuli to a subject while recording analog data and timestamps of neural activity retrieved from a window discriminator. The system utilizes the most recent real-time (RT) technology in order to provide not only a guaranteed data acquisition rate of 1 kHz, but a much more difficult to achieve guaranteed system response time of 1 ms. The system interface is windows-based and easy to use, providing a host of configurable options for end-user customization. PMID:15698659

  4. Real-Time Unsteady Loads Measurements Using Hot-Film Sensors

    NASA Technical Reports Server (NTRS)

    Mangalam, Arun S.; Moes, Timothy R.

    2004-01-01

    Several flight-critical aerodynamic problems such as buffet, flutter, stall, and wing rock are strongly affected or caused by abrupt changes in unsteady aerodynamic loads and moments. Advanced sensing and flow diagnostic techniques have made possible simultaneous identification and tracking, in real-time, of the critical surface, viscosity-related aerodynamic phenomena under both steady and unsteady flight conditions. The wind tunnel study reported here correlates surface hot-film measurements of leading edge stagnation point and separation point, with unsteady aerodynamic loads on a NACA 0015 airfoil. Lift predicted from the correlation model matches lift obtained from pressure sensors for an airfoil undergoing harmonic pitchup and pitchdown motions. An analytical model was developed that demonstrates expected stall trends for pitchup and pitchdown motions. This report demonstrates an ability to obtain unsteady aerodynamic loads in real-time, which could lead to advances in air vehicle safety, performance, ride-quality, control, and health management.

  5. Development of a capacitive ice sensor to measure ice growth in real time.

    PubMed

    Zhi, Xiang; Cho, Hyo Chang; Wang, Bo; Ahn, Cheol Hee; Moon, Hyeong Soon; Go, Jeung Sang

    2015-01-01

    This paper presents the development of the capacitive sensor to measure the growth of ice on a fuel pipe surface in real time. The ice sensor consists of pairs of electrodes to detect the change in capacitance and a thermocouple temperature sensor to examine the ice formation situation. In addition, an environmental chamber was specially designed to control the humidity and temperature to simulate the ice formation conditions. From the humidity, a water film is formed on the ice sensor, which results in an increase in capacitance. Ice nucleation occurs, followed by the rapid formation of frost ice that decreases the capacitance suddenly. The capacitance is saturated. The developed ice sensor explains the ice growth providing information about the icing temperature in real time. PMID:25808770

  6. Dynamical theory of spin noise and relaxation: Prospects for real-time NMR measurements.

    PubMed

    Field, Timothy R

    2014-11-01

    Recent developments in theoretical aspects of spin noise and relaxation and their interrelationship reveal a modified spin density, distinct from the density matrix, as the necessary object to describe fluctuations in spin systems. These fluctuations are to be viewed as an intrinsic quantum mechanical property of such systems immersed in random magnetic environments and are observed as "spin noise" in the absence of any radio frequency excitation. With the prospect of ultrafast digitization, the role of spin noise in real-time parameter extraction for (NMR) spin systems, and the advantage over standard techniques, is of essential importance, especially for systems containing a small number of spins. In this article we outline prospects for harnessing the recent dynamical theory in terms of spin-noise measurement, with attention to real-time properties. PMID:25493776

  7. Real-time digital heterodyne interferometer for high resolution plasma density measurements at ISTTOK

    SciTech Connect

    Marques, T. G.; Gouveia, A.; Pereira, T.; Fortunato, J.; Carvalho, B. B.; Sousa, J.; Silva, C.; Fernandes, H.

    2008-10-15

    With the implementation of alternating discharges (ac) at the ISTTOK tokamak, the typical duration of the discharges increased from 35 to 250 ms. This time increase created the need for a real-time electron density measurement in order to control the plasma fueling. The diagnostic chosen for the real-time calculation was the microwave interferometer. The ISTTOK microwave interferometer is a heterodyne system with quadrature detection and a probing frequency of 100 GHz ({lambda}{sub 0}=3 mm). In this paper, a low-cost approach for real-time diagnostic using a digital signal programable intelligent computer embedded system is presented, which allows the measurement of the phase with a 1% fringe accuracy in less than 6 {mu}s. The system increases its accuracy by digitally correcting the offsets of the input signals and making use of a judicious lookup table optimized to improve the nonlinear behavior of the transfer curve. The electron density is determined at a rate of 82 kHz (limited by the analog to digital converter), and the data are transmitted for each millisecond although this last parameter could be much lower (around 12 {mu}s--each value calculated is transmitted). In the future, this same system is expected to control plasma actuators, such as the piezoelectric valve of the hydrogen injection system responsible for the plasma fueling.

  8. Modular instrumentation system for real-time measurements and control on reciprocating engines

    NASA Technical Reports Server (NTRS)

    Rice, W. J.; Birchenough, A. G.

    1980-01-01

    An instrumentation system was developed for reciprocating engines. Among the parameters measured are the indicated mean effective pressure, or theoretical work per cycle, and the mass fraction burn rate, a measure of the combustion rate in the cylinder. These computations are performed from measured cylinder pressure and crankshaft angle and are available in real time for the experimenter. A 100 or 200 consecutive-cycle sample is analyzed to reduce the effect of cyclic variations in the engine. Data are displayed in bargraph form, and the mean and standard deviation are computed. Other instruments are also described.

  9. Recent advances in real-time analysis of ionograms and ionospheric drift measurements with digisondes

    NASA Astrophysics Data System (ADS)

    Reinisch, B. W.; Huang, X.; Galkin, I. A.; Paznukhov, V.; Kozlov, A.

    2005-08-01

    Reliable long distance RF communication and transionospheric radio links depend critically on space weather, and specifically ionospheric conditions. Modern ground-based ionosondes provide space weather parameters in real-time including the vertical electron density distribution up to ˜1000 km and the velocity components of the ionospheric F region drift. A global network of digisondes distributes this information in real-time via internet connections. The quality of the automatic scaling of the echo traces in ionograms was a continuous concern ever since first attempts have been reported. The modern low-power ionosonde with ˜100 W transmitters (compared to several kilowatt for the older ionosondes) relies on more sophisticated signal processing to enhance the signal-to-noise ratio and to retrieve the essential ionospheric characteristics. Recent advances in the automatic scaling algorithm ARTIST have significantly increased the reliability of the autoscaled data, making the data, in combination with models, more useful for ionospheric now-casting. Vertical and horizontal F region drift velocities are a new real-time output of the digisondes. The “ionosonde drift” is derived from the measured Doppler frequency shift and angle of arrival of ionospherically reflected HF echoes, a method similar to that used by coherent VHF and incoherent scatter radars.

  10. Assessment of Spectroscopic, Real-time Ion Thruster Grid Erosion-rate Measurements

    NASA Technical Reports Server (NTRS)

    Domonkos, Matthew T.; Stevens, Richard E.

    2000-01-01

    The success of the ion thruster on the Deep Space One mission has opened the gate to the use of primary ion propulsion. Many of the projected planetary missions require throughput and specific impulse beyond those qualified to date. Spectroscopic, real-time ion thruster grid erosion-rate measurements are currently in development at the NASA Glenn Research Center. A preliminary investigation of the emission spectra from an NSTAR derivative thruster with titanium grid was conducted. Some titanium lines were observed in the discharge chamber; however, the signals were too weak to estimate the erosion of the screen grid. Nevertheless, this technique appears to be the only non-intrusive real-time means to evaluate screen grid erosion, and improvement of the collection optics is proposed. Direct examination of the erosion species using laser-induced fluorescence (LIF) was determined to be the best method for a real-time accelerator grid erosion diagnostic. An approach for a quantitative LIF diagnostic was presented.

  11. Environmental Measurement-While-Drilling System for Real-Time Field Screening of Contaminants

    SciTech Connect

    Bishop, L.B.; Lockwood, G.J.; Normann, R.A.; Selph, M.M.; Williams, C.V.

    1999-02-22

    Sampling during environmental drilling is essential to fully characterize the spatial distribution and migration of near surface contaminants. However, analysis of the samples is expensive and time-consuming: off-site laboratory analysis can take weeks or months. An alternative screening technology, Environmental Measurement-While-Drilling (EMWD), could save money and valuable time by quickly distinguishing between contaminated and uncontaminated areas. Real time measurements provided by an EMWD system enable on-the-spot decisions to be made regarding sampling strategies. The system also enhances worker safety and provides the added flexibility of being able to steer a drill bit in or out of hazardous zones.

  12. Real-time high-resolution measurement of collagen alignment in dynamically loaded soft tissue

    NASA Astrophysics Data System (ADS)

    York, Timothy; Kahan, Lindsey; Lake, Spencer P.; Gruev, Viktor

    2014-06-01

    A technique for creating maps of the direction and strength of fiber alignment in collagenous soft tissues is presented. The method uses a division of focal plane polarimeter to measure circularly polarized light transmitted through the tissue. The architecture of the sensor allows measurement of the retardance and fiber alignment at the full frame rate of the sensor without any moving optics. The technique compares favorably to the standard method of using a rotating polarizer. How the new technique enables real-time capture of the full angular spread of fiber alignment and retardance under various cyclic loading conditions is illustrated.

  13. Laser 3-D measuring system and real-time visual feedback for teaching and correcting breathing

    NASA Astrophysics Data System (ADS)

    Povšič, Klemen; Fležar, Matjaž; Možina, Janez; Jezeršek, Matija

    2012-03-01

    We present a novel method for real-time 3-D body-shape measurement during breathing based on the laser multiple-line triangulation principle. The laser projector illuminates the measured surface with a pattern of 33 equally inclined light planes. Simultaneously, the camera records the distorted light pattern from a different viewpoint. The acquired images are transferred to a personal computer, where the 3-D surface reconstruction, shape analysis, and display are performed in real time. The measured surface displacements are displayed with a color palette, which enables visual feedback to the patient while breathing is being taught. The measuring range is approximately 400×600×500 mm in width, height, and depth, respectively, and the accuracy of the calibrated apparatus is +/-0.7 mm. The system was evaluated by means of its capability to distinguish between different breathing patterns. The accuracy of the measured volumes of chest-wall deformation during breathing was verified using standard methods of volume measurements. The results show that the presented 3-D measuring system with visual feedback has great potential as a diagnostic and training assistance tool when monitoring and evaluating the breathing pattern, because it offers a simple and effective method of graphical communication with the patient.

  14. Real time pressure-volume loops in mice using complex admittance: measurement and implications.

    PubMed

    Kottam, Anil T G; Porterfield, John; Raghavan, Karthik; Fernandez, Daniel; Feldman, Marc D; Valvano, Jonathan W; Pearce, John A

    2006-01-01

    Real time left ventricular (LV) pressure-volume (P-V) loops have provided a framework for understanding cardiac mechanics in experimental animals and humans. Conductance measurements have been used for the past 25 years to generate an instantaneous left ventricular (LV) volume signal. The standard conductance method yields a combination of blood and ventricular muscle conductance; however, only the blood signal is used to estimate LV volume. The state of the art techniques like hypertonic saline injection and IVC occlusion, determine only a single steady-state value of the parallel conductance of the cardiac muscle. This is inaccurate, since the cardiac muscle component should vary instantaneously throughout the cardiac cycle as the LV contracts and fills, because the distance from the catheter to the muscle changes. The capacitive nature of cardiac muscle can be used to identify its contribution to the combined conductance signal. This method, in contrast to existing techniques, yields an instantaneous estimate of the parallel admittance of cardiac muscle that can be used to correct the measurement in real time. The corrected signal consists of blood conductance alone. We present the results of real time in vivo measurements of pressure-admittance and pressure-phase loops inside the murine left ventricle. We then use the magnitude and phase angle of the measured admittance to determine pressure volume loops inside the LV on a beat by beat basis. These results may be used to achieve a substantial improvement in the state of the art in this measurement method by eliminating the need for hypertonic saline injection. PMID:17946238

  15. Near Real-Time Isotopic Measurements of Carbon Dioxide from Outgassing Volcanoes

    NASA Astrophysics Data System (ADS)

    Stix, J.; Lucic, G.; Malowany, K.

    2014-12-01

    For the past several years we have been using a Picarro G1101-i isotopic mass analyzer to study the behavior of carbon dioxide emanating from active volcanoes. Because of its portability (it weighs about 30 kg), the instrument accompanies us on our field campaigns. Typically, we collect gas samples during the day and analyze them in the evening. The result is near-real-time isotopic measurements of CO2, and we are thus able to plan and adjust our field campaigns according to the results that we obtain on a continual basis. This is the primary advantage of the instrument. The G1101-i requires about 350 watts of power, typically provided by wall current with an uninterruptible power supply between the wall and instrument to deal with power fluctuations and outages. We calibrate the instrument every 2-5 days with a series of four well-characterized gas standards which we bring with us into the field in evacuated glass containers. Calibrations are typically robust and highly linear, with sub per mil precision. We also normally obtain a few samples which we analyze both by the G1101-i and later by mass spectrometry, in order to provide an independent means of checking our accuracy. Standards and samples are typically analyzed at similar CO2 concentrations to minimize any concentration-dependent effects on the isotopic analysis, even though these are generally small to negligible. Our applications so far have been focused at one caldera system and one subduction-related stratovolcano. We have analyzed soil gases at Long Valley caldera, California, to study the interplay of volcanic and tectonic controls upon diffuse CO2 release. We have analyzed CO2 in the the plume of Turrialba volcano, Costa Rica, to identify the volcanic isotopic signal and understand the mixing of the plume with surrounding atmosphere. At both localities, with appropriate dilutions as needed, we have been able to analyze the isotopic signal for CO2 concentrations ranging from atmospheric (400 ppm) to

  16. Real-time measurement of skin erythema variation by negative compression: pilot study

    NASA Astrophysics Data System (ADS)

    Jung, Byungjo; Kim, Soobyeong; Bae, Yunjin; Kang, Heesung; Lee, Yongheum; Nelson, J. Stuart

    2012-08-01

    Skin erythema has been widely used as a diagnostic parameter in dermatology. This study describes a methodology for real-time measurement of skin erythema variation induced by negative compression. This study developed an optical measurement probe, which includes a RGB color sensor that translates in the vertical direction, with the magnitude of vertical translation dependening on the amount of skin deformation. Real-time measurement of erythema variation as a function of both negative compression and time was performed in vivo on 10 measurement sites located on the back of each of 12 volunteers who participated in this study. Negative compression was sequentially applied from -30 to -80 kPa and continuously at a constant magnitude (-80 kPa) condition. The results showed that skin erythema was uniformly induced at the measurement sites and linearly increased as a function of both negative compression and time. A wide range of individual variation was noted for skin erythema, which may be due to variations in anisotropic skin properties between volunteers. This study demonstrated the clinical feasibility of a novel optical device for skin erythema measurement. Future studies are needed to investigate the clinical applications of this device.

  17. Application of fiber Bragg grating sensors to real-time strain measurement of cryogenic tanks

    NASA Astrophysics Data System (ADS)

    Takeda, Nobuo; Mizutani, Tadahito; Hayashi, Kentaro; Okabe, Yoji

    2003-08-01

    Although many researches of strain measurement using fiber Bragg grating (FBG) sensors were conducted, there were few applications of FBG sensors to spacecraft in operation. It is very significant to develop an onboard system for the real-time strain measurement during the flight operation. In the present research, the real-time strain measurement of a composite liquid hydrogen (LH2) tank, which consisted of CFRP and aluminum liner, was attempted. Adhesive property of the FBG sensors was investigated first of all. As a result, UV coated FBG sensors and polyurethane adhesive were adopted. Then, reflection spectra from FBG sensors were measured through the tensile test at liquid helium (LHe) temperature. Since the center wavelength shifted in proportion to the applied strain, the FBG sensor was suitable as a precise strain sensor even at LHe temperature. Next, the development of an onboard FBG demodulator was discussed. This onboard demodulator was designed for weight saving to be mounted on a reusable rocket vehicle test (RVT) operated by the Institute of Space and Astronautical Science (ISAS). FBG sensors were bonded on the surface of the composite LH2 tank for the RVT. Then, strain measurement using the onboard demodulator was conducted through the cryogenic pressure test of the tank and compared with the result measured using the optical spectrum analyzer (OSA).

  18. NMDB: real-time database for high resolution neutron monitor measurements

    NASA Astrophysics Data System (ADS)

    Steigies, Christian

    The worldwide network of standardized neutron monitors is, after 50 years, still the stateof-the-art instrumentation to measure variations of the primary cosmic rays in the energy range 500 MeV-60 GeV. These measurements are an ideal complement to space based cosmic ray measurements. Unlike data from satellite experiments, neutron monitor data has never been available in high time resolution from many neutron monitor stations in real-time. The data is often available only from the individual station's website, in varying formats, and not in real-time. To overcome this deficit, the European Commission is supporting the Neutron Monitor database (NMDB) since January 2008 as an e-Infrastructures project in the Seventh Framework Programme in the Capacities section. Neutron Monitor stations that do not yet have 1-minute resolution will be supported by software and the development of an affordable standard registration system to submit the measurements to the database via internet in realtime. This resolves the problem of different data formats and for the first time allows use of realtime cosmic ray measurements for space weather applications. Besides creating a database and developing applications that use this data, a part of the project is dedicated to create a public outreach website to inform about cosmic rays and possible effects on humans, technological systems, and the environment.

  19. Real-time direct measurement of diffraction efficiency of reflection gratings in photopolymer recording materials

    NASA Astrophysics Data System (ADS)

    Vojtíšek, Petr; Květoň, Milan

    2015-01-01

    Photopolymer recording systems have received a great deal of attention as a material for optical information storage and production of diffraction gratings. Before using these materials in such systems, it is important to characterize them and understand the processes which run during holographic recording, so that the recording itself can be optimized to obtain an efficient diffraction grating. In this contribution, we present a new method for real-time measurement of the diffraction response of reflection gratings during the recording process. Usually, the recording process in photopolymers is characterized by the real-time measurement of a transmission diffraction grating growth. This method does not allow measuring the growth of gratings with a very narrow spatial period in the reflection configuration. The new approach is based on the idea that the reflection grating is illuminated with white light at a different angle from the recording one and the diffraction efficiency is continuously measured with a spectrophotometer. Kogelnik's coupled wave theory is used as the theoretical background in this contribution. Experimentally, the photopolymer Bayfol HX has been tested in the reflection configuration and growth curves have been measured to show a good applicability of the detection method.

  20. Real-time Measurements of Amino Acid and Protein Hydroperoxides Using Coumarin Boronic Acid*

    PubMed Central

    Michalski, Radoslaw; Zielonka, Jacek; Gapys, Ewa; Marcinek, Andrzej; Joseph, Joy; Kalyanaraman, Balaraman

    2014-01-01

    Hydroperoxides of amino acid and amino acid residues (tyrosine, cysteine, tryptophan, and histidine) in proteins are formed during oxidative modification induced by reactive oxygen species. Amino acid hydroperoxides are unstable intermediates that can further propagate oxidative damage in proteins. The existing assays (oxidation of ferrous cation and iodometric assays) cannot be used in real-time measurements. In this study, we show that the profluorescent coumarin boronic acid (CBA) probe reacts with amino acid and protein hydroperoxides to form the corresponding fluorescent product, 7-hydroxycoumarin. 7-Hydroxycoumarin formation was catalase-independent. Based on this observation, we have developed a fluorometric, real-time assay that is adapted to a multiwell plate format. This is the first report showing real-time monitoring of amino acid and protein hydroperoxides using the CBA-based assay. This approach was used to detect protein hydroperoxides in cell lysates obtained from macrophages exposed to visible light and photosensitizer (rose bengal). We also measured the rate constants for the reaction between amino acid hydroperoxides (tyrosyl, tryptophan, and histidine hydroperoxides) and CBA, and these values (7–23 m−1 s−1) were significantly higher than that measured for H2O2 (1.5 m−1 s−1). Using the CBA-based competition kinetics approach, the rate constants for amino acid hydroperoxides with ebselen, a glutathione peroxidase mimic, were also determined, and the values were within the range of 1.1–1.5 × 103 m−1 s−1. Both ebselen and boronates may be used as small molecule scavengers of amino acid and protein hydroperoxides. Here we also show formation of tryptophan hydroperoxide from tryptophan exposed to co-generated fluxes of nitric oxide and superoxide. This observation reveals a new mechanism for amino acid and protein hydroperoxide formation in biological systems. PMID:24928516

  1. Real time kinetic flow cytometry measurements of cellular parameter changes evoked by nanosecond pulsed electric field.

    PubMed

    Orbán, Csaba; Pérez-García, Esther; Bajnok, Anna; McBean, Gethin; Toldi, Gergely; Blanco-Fernandez, Alfonso

    2016-05-01

    Nanosecond pulsed electric field (nsPEF) is a novel method to increase cell proliferation rate. The phenomenon is based on the microporation of cellular organelles and membranes. However, we have limited information on the effects of nsPEF on cell physiology. Several studies have attempted to describe the effects of this process, however no real time measurements have been conducted to date. In this study we designed a model system which allows the measurement of cellular processes before, during and after nsPEF treatment in real time. The system employs a Vabrema Mitoplicator(TM) nsPEF field generating instrument connected to a BD Accuri C6 cytometer with a silicon tube led through a peristaltic pump. This model system was applied to observe the effects of nsPEF in mammalian C6 glioblastoma (C6 glioma) and HEK-293 cell lines. Viability (using DRAQ7 dye), intracellular calcium levels (using Fluo-4 dye) and scatter characteristics were measured in a kinetic manner. Data were analyzed using the FACSKin software. The viability and morphology of the investigated cells was not altered upon nsPEF treatment. The response of HEK-293 cells to ionomycin as positive control was significantly lower in the nsPEF treated samples compared to non-treated cells. This difference was not observed in C6 cells. FSC and SSC values were not altered significantly by the nsPEF treatment. Our results indicate that this model system is capable of reliably investigating the effects of nsPEF on cellular processes in real time. © 2016 International Society for Advancement of Cytometry. PMID:26990601

  2. Real-time measurement of internal stress of dental tissue using holography

    NASA Astrophysics Data System (ADS)

    Pantelic, Dejan; Blazic, Larisa; Savic-Sevic, Svetlana; Muric, Branka; Vasiljevic, Darko; Panic, Bratimir; Belic, Ilija

    2007-05-01

    We describe a real-time holographic technique used to observe dental contraction due to photo-polymerization of dental filling during LED lamp illumination. An off-axis setup was used, with wet in-situ processing of the holographic plate, and consequent recording of interference fringes using CCD camera. Finite elements method was used to calculate internal stress of dental tissue, corresponding to experimentally measured deformation. A technique enables selection of preferred illumination method with reduced polymerization contraction. As a consequence, durability of dental filling might be significantly improved.

  3. Real time drift measurement for colloidal probe atomic force microscope: a visual sensing approach

    SciTech Connect

    Wang, Yuliang Bi, Shusheng; Wang, Huimin

    2014-05-15

    Drift has long been an issue in atomic force microscope (AFM) systems and limits their ability to make long time period measurements. In this study, a new method is proposed to directly measure and compensate for the drift between AFM cantilevers and sample surfaces in AFM systems. This was achieved by simultaneously measuring z positions for beads at the end of an AFM colloidal probe and on sample surface through an off-focus image processing based visual sensing method. The working principle and system configuration are presented. Experiments were conducted to validate the real time drift measurement and compensation. The implication of the proposed method for regular AFM measurements is discussed. We believe that this technique provides a practical and efficient approach for AFM experiments requiring long time period measurement.

  4. Real-time estimation of the structural response using limited measured data

    NASA Astrophysics Data System (ADS)

    Sedarat, Hassan; Talebinejad, Iman; Emami-Naeini, Abbas; Falck, David; van der Linden, Gwendolyn; Nobari, Farid; Krimotat, Alex; Lynch, Jerome

    2014-03-01

    This study introduces an efficient procedure to estimate the structural response of a suspension bridge in real-time based on a limited set of measured data. Unlike conventional techniques, the proposed procedure does not employ mode shapes and frequencies. In this study, the proposed technique is used to estimate the response of a suspension bridge structure based on a set of strain gauge measurements. Finite element analysis is performed only once to set up the structural parameters, namely computed flexibility matrix, and computed hanger forces matrix. The response of the bridge was estimated without any additional finite element analysis using the computed structural parameters and the measured hanger strains. The Alfred Zampa Memorial Bridge, on Interstate 80 in California, was selected for this study. A high fidelity finite element model of the bridge was developed using the general purpose computer program ADINA. The proposed method has been proven to have the capability to estimate any type of structural response in real time based on the measured hanger strains, and provides an important part of an integrated Structure Health Monitoring (SHM) system for major bridges.

  5. Real-Time Measurements of Aft Dome Insulation Erosion on Space Shuttle Reusable Solid Rocket Motor

    NASA Technical Reports Server (NTRS)

    McWhorter, Bruce; Ewing, Mark; Albrechtsen, Kevin; Noble, Todd; Longaker, Matt

    2004-01-01

    Real-time erosion of aft dome internal insulation was measured with internal instrumentation on a static test of a lengthened version of the Space Shuffle Reusable Solid Rocket Motor (RSRM). This effort marks the first time that real-time aft dome insulation erosion (Le., erosion due to the combined effects of thermochemical ablation and mechanical abrasion) was measured in this kind of large motor static test [designated as Engineering Test Motor number 3 (ETM3)I. This paper presents data plots of the erosion depth versus time. The data indicates general erosion versus time behavior that is in contrast to what would be expected from earlier analyses. Engineers have long known that the thermal environment in the aft dome is severe and that the resulting aft dome insulation erosion is significant. Models of aft dome erosion involve a two-step process of computational fluid dynamics (CFD) modeling and material ablation modeling. This modeling effort is complex. The time- dependent effects are difficult to verify with only prefire and postfire insulation measurements. Nozzle vectoring, slag accumulation, and changing boundary conditions will affect the time dependence of aft dome erosion. Further study of this data and continued measurements on future motors will increase our understanding of the aft dome flow and erosion environment.

  6. An evaluation of technologies for real-time measurement of rates of outdoor airflow into HVAC systems

    SciTech Connect

    Fisk, William J.; Faulkner, David; Sullivan, Douglas P.

    2004-09-01

    During the last few years, new technologies have been introduced for real-time continuous measurement of the flow rates of outdoor air (OA) into HVAC systems; however, an evaluation of these measurement technologies has not previously been published. This document describes a test system and protocols developed for a controlled evaluation of these measurement technologies. The results of tests of four commercially available measurement technologies and one prototype based on a new design are also summarized. The test system and protocol were judged practical and very useful. The series of tests identified three commercially available measurement technologies that should provide reasonably accurate measurements of OA flow rates as long as air velocities are maintained high enough to produce accurately measurable pressure signals. In HVAC systems with economizer controls, to maintain the required air velocities the OA intake will need to be divided into two sections in parallel, each with a separate OA damper. The errors in OA flow rates measured with the fourth commercially available measurement technology were 20% to 30% with horizontal probes but much larger with vertical probes. The new prototype measurement technology was the only one that appears suitable for measuring OA flow rates over their full range from 20% OA to 100% OA without using two separate OA dampers. All of the measurement devices had pressure drops that are likely to be judged acceptable. The influence of wind on the accuracy of these measurement technologies still needs to be evaluated.

  7. Graphics processing unit-assisted real-time three-dimensional measurement using speckle-embedded fringe.

    PubMed

    Feng, Shijie; Chen, Qian; Zuo, Chao

    2015-08-01

    This paper presents a novel two-frame fringe projection technique for real-time, accurate, and unambiguous three-dimensional (3D) measurement. One of the frames is a digital speckle pattern, and the other one is a composite image which is generated by fusing that speckle image with sinusoidal fringes. The contained sinusoidal component is used to obtain a wrapped phase map by Fourier transform profilometry, and the speckle image helps determine the fringe order for phase unwrapping. Compared with traditional methods, the proposed pattern scheme enables measurements of discontinuous surfaces with only two frames, greatly reducing the number of required patterns and thus reducing the sensitivity to movements. This merit makes the method very suitable for inspecting dynamic scenes. Moreover, it shows close performance in measurement accuracy compared with the phase-shifting method from our experiments. To process data in real time, a Compute Unified Device Architecture-enabled graphics processing unit is adopted to accelerate some time-consuming computations. With our system, measurements can be performed at 21 frames per second with a resolution of 307,000 points per frame. PMID:26368103

  8. Rapid and Accurate Identification by Real-Time PCR of Biotoxin-Producing Dinoflagellates from the Family Gymnodiniaceae

    PubMed Central

    Smith, Kirsty F.; de Salas, Miguel; Adamson, Janet; Rhodes, Lesley L.

    2014-01-01

    The identification of toxin-producing dinoflagellates for monitoring programmes and bio-compound discovery requires considerable taxonomic expertise. It can also be difficult to morphologically differentiate toxic and non-toxic species or strains. Various molecular methods have been used for dinoflagellate identification and detection, and this study describes the development of eight real-time polymerase chain reaction (PCR) assays targeting the large subunit ribosomal RNA (LSU rRNA) gene of species from the genera Gymnodinium, Karenia, Karlodinium, and Takayama. Assays proved to be highly specific and sensitive, and the assay for G. catenatum was further developed for quantification in response to a bloom in Manukau Harbour, New Zealand. The assay estimated cell densities from environmental samples as low as 0.07 cells per PCR reaction, which equated to three cells per litre. This assay not only enabled conclusive species identification but also detected the presence of cells below the limit of detection for light microscopy. This study demonstrates the usefulness of real-time PCR as a sensitive and rapid molecular technique for the detection and quantification of micro-algae from environmental samples. PMID:24608972

  9. A non-contact real-time measurement of lamp dimension based on machine vision

    NASA Astrophysics Data System (ADS)

    Song, Li-mei; Wang, Peng-qiang; Chang, Yu-lan; Li, Xiao-jie; Xi, Jiang-tao; Guo, Qing-hua; Li, Bing-nan

    2015-03-01

    In order to realize the online measurement of lamp dimension, the bulb image dimension measurement based on vision (BIDMV) is proposed. The image of lamp is obtained by camera. After image processing, such as Otsu algorithm, median filter, ellipse fitting and envelope rectangle fitting, the dimension of lamp can be calculated. Based on this method, a non-contact real-time measurement system of the lamp's dimension is developed. The precision of the proposed method is 0.07 mm, and it can satisfy the tolerance of the National Standard GB15766.1-2008. The experiment results show that the proposed method has a faster measuring speed and a higher precision compared with other measurement methods.

  10. Design and implementation of real-time LED spatial radiance measurement systems

    NASA Astrophysics Data System (ADS)

    Chang, Gao-Wei; Yeh, Zong-Mu; Liao, Chia-Cheng

    2007-02-01

    Light-emitting diodes (LEDs) have been recognized as a generation of new light sources because they possess the properties of energy-saving, environmental protection, long lifetime, and those lacking in conventional lighting. To satisfy the requirements for different applications (e.g., for large-scale displays), determining the spatial radiances of LEDs is important to identifying their viewing angle and utilizing their lighting efficiency. The objective of this paper is to build up a real-time spatial radiance measurement system for LEDs, on the basis of digital signal processing (DSP) techniques. In this paper, the system analysis is given to show the feasibility of this work. Two primary subsystems are devised to perform the real-time measurements. First, in the optoelectronic sensing and signal processing subsystem, a wide-bandwidth photodiode sensing circuit is employed to acquire optical signals at a high speed, and an automatic gain control (AGC) circuit is designed to increase the measurement range. To support high-speed data processing, a DSP-based platform is developed in the subsystem. Second, a light-source rotation scheme is used in the optomechanical subsystem. For performance evaluations, we adopt a standard calibrating light source to test and verify our system. Experimental results indicate that the proposed system gives satisfactory results.

  11. Accurate measurement of time

    NASA Astrophysics Data System (ADS)

    Itano, Wayne M.; Ramsey, Norman F.

    1993-07-01

    The paper discusses current methods for accurate measurements of time by conventional atomic clocks, with particular attention given to the principles of operation of atomic-beam frequency standards, atomic hydrogen masers, and atomic fountain and to the potential use of strings of trapped mercury ions as a time device more stable than conventional atomic clocks. The areas of application of the ultraprecise and ultrastable time-measuring devices that tax the capacity of modern atomic clocks include radio astronomy and tests of relativity. The paper also discusses practical applications of ultraprecise clocks, such as navigation of space vehicles and pinpointing the exact position of ships and other objects on earth using the GPS.

  12. Real-time quantitative fluorescence measurement of microscale cell culture analog systems

    NASA Astrophysics Data System (ADS)

    Oh, Taek-il; Kim, Donghyun; Tatosian, Daniel; Sung, Jong Hwan; Shuler, Michael

    2007-02-01

    A microscale cell culture analog (μCCA) is a cell-based lab-on-a-chip assay that, as an animal surrogate, is applied to pharmacological studies for toxicology tests. A μCCA typically comprises multiple chambers and microfluidics that connect the chambers, which represent animal organs and blood flow to mimic animal metabolism more realistically. A μCCA is expected to provide a tool for high-throughput drug discovery. Previously, a portable fluorescence detection system was investigated for a single μCCA device in real-time. In this study, we present a fluorescence-based imaging system that provides quantitative real-time data of the metabolic interactions in μCCAs with an emphasis on measuring multiple μCCA samples simultaneously for high-throughput screening. The detection system is based on discrete optics components, with a high-power LED and a charge-coupled device (CCD) camera as a light source and a detector, for monitoring cellular status on the chambers of each μCCA sample. Multiple samples are characterized mechanically on a motorized linear stage, which is fully-automated. Each μCCA sample has four chambers, where cell lines MES-SA/DX- 5, and MES-SA (tumor cells of human uterus) have been cultured. All cell-lines have been transfected to express the fusion protein H2B-GFP, which is a human histone protein fused at the amino terminus to EGFP. As a model cytotoxic drug, 10 μM doxorubicin (DOX) was used. Real-time quantitative data of the intensity loss of enhanced green fluorescent protein (EGFP) during cell death of target cells have been collected over several minutes to 40 hours. Design issues and improvements are also discussed.

  13. [Measuring leg length and leg length difference with the method of real time sonography].

    PubMed

    Holst, A; Thomas, W

    1988-06-01

    A brief presentation of the clinical and radiological methods to measure the leg length and the leg length difference is followed by an outline of the new diagnostic method for measuring the leg length and the leg length difference by means of real-time sonography. Tests conducted on corpses, as well as clinical examples, show that sonography is an ideal method for determining the exact lengths of the femur and tibia. The joint gaps on the hip joint, knee joint and upper ankle joint can be visualised by means of a 5 MHz linear scanner. A 1 mm strong metal bar on the skin and under the scanner are positioned at a right angle to the longitudinal axis of the body so that the bar can be seen in the centre of each joint gap by means of real-time sonography. A measuring device gives the distances of the joint gaps in cm so that the differences correspond to the real length of femur and tibia. This standardised measuring procedure is done by a specially developed bearing and measuring device. The results of the sonographical measurings on 20 corpses and checking after consecutive dissections showed in 75% of the cases a 100% sonographic measuring accuracy of the total leg length. The separately considered results for femur (85%) and tibia (90%) were even better. The maximum sonographic measuring fault was 1.0 cm for the femur (in one case) and 0.5 cm for the tibia, respectively. Thus, sonographic measuring of the leg length offers a reliable, non-invasive and easily performed new method that can be repeated any number of times. It is ideal for the development control of therapeutically influenced as well as spontaneous transformations of leg length differences. PMID:3071879

  14. Obtaining Reliable Predictions of Terrestrial Energy Coupling From Real-Time Solar Wind Measurements

    NASA Technical Reports Server (NTRS)

    Weimer, Daniel R.

    2002-01-01

    Measurements of the interplanetary magnetic field (IMF) from the ACE (Advanced Composition Explorer), Wind, IMP-8 (Interplanetary Monitoring Platform), and Geotail spacecraft have revealed that the IMF variations are contained in phase planes that are tilted with respect to the propagation direction, resulting in continuously variable changes in propagation times between spacecraft, and therefore, to the Earth. Techniques for using 'minimum variance analysis' have been developed in order to be able to measure the phase front tilt angles, and better predict the actual propagation times from the L1 orbit to the Earth, using only the real-time IMF measurements from one spacecraft. The use of empirical models with the IMF measurements at L1 from ACE (or future satellites) for predicting 'space weather' effects has also been demonstrated.

  15. Using Indirect Turbulence Measurements for Real-Time Parameter Estimation in Turbulent Air

    NASA Technical Reports Server (NTRS)

    Martos, Borja; Morelli, Eugene A.

    2012-01-01

    The use of indirect turbulence measurements for real-time estimation of parameters in a linear longitudinal dynamics model in atmospheric turbulence was studied. It is shown that measuring the atmospheric turbulence makes it possible to treat the turbulence as a measured explanatory variable in the parameter estimation problem. Commercial off-the-shelf sensors were researched and evaluated, then compared to air data booms. Sources of colored noise in the explanatory variables resulting from typical turbulence measurement techniques were identified and studied. A major source of colored noise in the explanatory variables was identified as frequency dependent upwash and time delay. The resulting upwash and time delay corrections were analyzed and compared to previous time shift dynamic modeling research. Simulation data as well as flight test data in atmospheric turbulence were used to verify the time delay behavior. Recommendations are given for follow on flight research and instrumentation.

  16. Linking Near Real-Time Water Quality Measurements to Fecal Coliforms and Trace Organic Pollutants in Urban Streams

    NASA Astrophysics Data System (ADS)

    Henjum, M.; Wennen, C.; Hondzo, M.; Hozalski, R. M.; Novak, P. J.; Arnold, W. A.

    2009-05-01

    Anthropogenic pollutants, including pesticides, herbicides, pharmaceuticals, and estrogens are detected in urban water bodies. Effective examination of dilute organic and microbial pollutant loading rates within surface waters is currently prohibitively expensive and labor intensive. Effort is being placed on the development of improved monitoring methodologies to more accurately assess surface water quality and evaluate the effectiveness of water quality management practices. Throughout the summer and fall of 2008 a "real-time" wireless network equipped with high frequency fundamental water quality parameter sensors measured turbidity, conductivity, pH, depth, temperature, dissolved oxygen and nitrate above and below stormwater inputs at two urban stream locations. At each location one liter grab samples were concurrently collected by ISCO automatic samplers at two hour intervals for 24 hour durations during three dry periods and five rain events. Grab samples were analyzed for fecal coliforms, atrazine (agricultural herbicide), prometon (residential herbicide) and caffeine (wastewater indicator). Surrogate relationships between easy-to-measure water quality parameters and difficult-to-measure pollutants were developed, subsequently facilitating monitoring of these pollutants without the development of new, and likely costly, technologies. Additionally, comparisons were made between traditional grab sampling techniques and the "real-time" monitoring to assess the accuracy of Total Maximum Daily Load (TMDL) calculations.

  17. Strengthening HIV surveillance: measurements to track the epidemic in real time.

    PubMed

    Buthelezi, Usangiphile E; Davidson, Candace L; Kharsany, Ayesha Bm

    2016-07-01

    Surveillance for HIV as a public health initiative requires timely, detailed and robust data to systematically understand burden of infection, transmission patterns, direct prevention efforts, guide funding, identify new infections and predict future trends in the epidemic. The methods for HIV surveillance have evolved to reliably track the epidemic and identify new infections in real time. Initially HIV surveillance relied primarily on the reporting of AIDS cases followed by measuring antibodies to HIV to determine prevalence in key populations. With the roll-out of antiretroviral therapy (ART) resulting in better survival and the corresponding increase in HIV prevalence, the landscape of surveillance shifted further to track HIV prevalence and incidence within the context of programmes. Recent developments in laboratory assays that potentially measure and differentiate recent versus established HIV infection offer a cost-effective method for the rapid estimation of HIV incidence. These tests continue to be validated and are increasingly useful in informing the status of the epidemic in real time. Surveillance of heterogeneity of infections contributing to sub-epidemics requires methods to identify affected populations, density, key geographical locations and phylogenetically linked or clustered infections. Such methods could provide a nuanced understanding of the epidemic and prioritise prevention efforts to those most vulnerable. This paper brings together recent developments and challenges facing HIV surveillance, together with the application of newer assays and methods to fast-track the HIV prevention and treatment response. PMID:27399039

  18. In situ real-time measurement of physical characteristics of airborne bacterial particles

    NASA Astrophysics Data System (ADS)

    Jung, Jae Hee; Lee, Jung Eun

    2013-12-01

    Bioaerosols, including aerosolized bacteria, viruses, and fungi, are associated with public health and environmental problems. One promising control method to reduce the harmful effects of bioaerosols is thermal inactivation via a continuous-flow high-temperature short-time (HTST) system. However, variations in bioaerosol physical characteristics - for example, the particle size and shape - during the continuous-flow inactivation process can change the transport properties in the air, which can affect particle deposition in the human respiratory system or the filtration efficiency of ventilation systems. Real-time particle monitoring techniques are a desirable alternative to the time-consuming process of microscopic analysis that is conventionally used in sampling and particle characterization. Here, we report in situ real-time optical scattering measurements of the physical characteristics of airborne bacteria particles following an HTST process in a continuous-flow system. Our results demonstrate that the aerodynamic diameter of bacterial aerosols decreases when exposed to a high-temperature environment, and that the shape of the bacterial cells is significantly altered. These variations in physical characteristics using optical scattering measurements were found to be in agreement with the results of scanning electron microscopy analysis.

  19. Real-time high-resolution heterodyne-based measurements of spectral dynamics in fibre lasers

    PubMed Central

    Sugavanam, Srikanth; Fabbri, Simon; Le, Son Thai; Lobach, Ivan; Kablukov, Sergey; Khorev, Serge; Churkin, Dmitry

    2016-01-01

    Conventional tools for measurement of laser spectra (e.g. optical spectrum analysers) capture data averaged over a considerable time period. However, the generation spectrum of many laser types may involve spectral dynamics whose relatively fast time scale is determined by their cavity round trip period, calling for instrumentation featuring both high temporal and spectral resolution. Such real-time spectral characterisation becomes particularly challenging if the laser pulses are long, or they have continuous or quasi-continuous wave radiation components. Here we combine optical heterodyning with a technique of spatio-temporal intensity measurements that allows the characterisation of such complex sources. Fast, round-trip-resolved spectral dynamics of cavity-based systems in real-time are obtained, with temporal resolution of one cavity round trip and frequency resolution defined by its inverse (85 ns and 24 MHz respectively are demonstrated). We also show how under certain conditions for quasi-continuous wave sources, the spectral resolution could be further increased by a factor of 100 by direct extraction of phase information from the heterodyned dynamics or by using double time scales within the spectrogram approach. PMID:26984634

  20. Real-time setup to measure radon emission during rock deformation: implications for geochemical surveillance

    NASA Astrophysics Data System (ADS)

    Tuccimei, P.; Mollo, S.; Soligo, M.; Scarlato, P.; Castelluccio, M.

    2015-05-01

    Laboratory experiments can represent a valid approach to unravel the complex interplay between the geochemical behaviour of radon and rock deformation mechanisms. In light of this, we present a new real-time experimental setup for analysing in continuum the alpha-emitting 222Rn and 220Rn daughters over variable stress-strain regimes. The most innovative segment of this setup consists of the radon accumulation chamber obtained from a tough and durable material that can host large cylindrical rock samples. The accumulation chamber is connected, in a closed-loop configuration, to a gas-drying unit and to a RAD7 radon monitor. A recirculating pump moves the gas from the rock sample to a solid-state detector for alpha counting of radon and thoron progeny. The measured radon signal is enhanced by surrounding the accumulation chamber with a digitally controlled heating belt. As the temperature is increased, the number of effective collisions of radon atoms increases favouring the diffusion of radon through the material and reducing the analytical uncertainty. The accumulation chamber containing the sample is then placed into a uniaxial testing apparatus where the axial deformation is measured throughout a linear variable displacement transducer. A dedicated software allows obtaining a variety of stress-strain regimes from fast deformation rates to long-term creep tests. Experiments conducted with this new real-time setup have important ramifications for the interpretation of geochemical anomalies recorded prior to volcanic eruptions or earthquakes.

  1. Complexity-Measure-Based Sequential Hypothesis Testing for Real-Time Detection of Lethal Cardiac Arrhythmias

    NASA Astrophysics Data System (ADS)

    Chen, Szi-Wen

    2006-12-01

    A novel approach that employs a complexity-based sequential hypothesis testing (SHT) technique for real-time detection of ventricular fibrillation (VF) and ventricular tachycardia (VT) is presented. A dataset consisting of a number of VF and VT electrocardiogram (ECG) recordings drawn from the MIT-BIH database was adopted for such an analysis. It was split into two smaller datasets for algorithm training and testing, respectively. Each ECG recording was measured in a 10-second interval. For each recording, a number of overlapping windowed ECG data segments were obtained by shifting a 5-second window by a step of 1 second. During the windowing process, the complexity measure (CM) value was calculated for each windowed segment and the task of pattern recognition was then sequentially performed by the SHT procedure. A preliminary test conducted using the database produced optimal overall predictive accuracy of[InlineEquation not available: see fulltext.]. The algorithm was also implemented on a commercial embedded DSP controller, permitting a hardware realization of real-time ventricular arrhythmia detection.

  2. Optimized quantum sensing with a single electron spin using real-time adaptive measurements

    NASA Astrophysics Data System (ADS)

    Bonato, C.; Blok, M. S.; Dinani, H. T.; Berry, D. W.; Markham, M. L.; Twitchen, D. J.; Hanson, R.

    2016-03-01

    Quantum sensors based on single solid-state spins promise a unique combination of sensitivity and spatial resolution. The key challenge in sensing is to achieve minimum estimation uncertainty within a given time and with high dynamic range. Adaptive strategies have been proposed to achieve optimal performance, but their implementation in solid-state systems has been hindered by the demanding experimental requirements. Here, we realize adaptive d.c. sensing by combining single-shot readout of an electron spin in diamond with fast feedback. By adapting the spin readout basis in real time based on previous outcomes, we demonstrate a sensitivity in Ramsey interferometry surpassing the standard measurement limit. Furthermore, we find by simulations and experiments that adaptive protocols offer a distinctive advantage over the best known non-adaptive protocols when overhead and limited estimation time are taken into account. Using an optimized adaptive protocol we achieve a magnetic field sensitivity of 6.1 ± 1.7 nT Hz-1/2 over a wide range of 1.78 mT. These results open up a new class of experiments for solid-state sensors in which real-time knowledge of the measurement history is exploited to obtain optimal performance.

  3. A robust adaptive denoising framework for real-time artifact removal in scalp EEG measurements

    NASA Astrophysics Data System (ADS)

    Kilicarslan, Atilla; Grossman, Robert G.; Contreras-Vidal, Jose Luis

    2016-04-01

    Objective. Non-invasive measurement of human neural activity based on the scalp electroencephalogram (EEG) allows for the development of biomedical devices that interface with the nervous system for scientific, diagnostic, therapeutic, or restorative purposes. However, EEG recordings are often considered as prone to physiological and non-physiological artifacts of different types and frequency characteristics. Among them, ocular artifacts and signal drifts represent major sources of EEG contamination, particularly in real-time closed-loop brain-machine interface (BMI) applications, which require effective handling of these artifacts across sessions and in natural settings. Approach. We extend the usage of a robust adaptive noise cancelling (ANC) scheme ({H}∞ filtering) for removal of eye blinks, eye motions, amplitude drifts and recording biases simultaneously. We also characterize the volume conduction, by estimating the signal propagation levels across all EEG scalp recording areas due to ocular artifact generators. We find that the amplitude and spatial distribution of ocular artifacts vary greatly depending on the electrode location. Therefore, fixed filtering parameters for all recording areas would naturally hinder the true overall performance of an ANC scheme for artifact removal. We treat each electrode as a separate sub-system to be filtered, and without the loss of generality, they are assumed to be uncorrelated and uncoupled. Main results. Our results show over 95-99.9% correlation between the raw and processed signals at non-ocular artifact regions, and depending on the contamination profile, 40-70% correlation when ocular artifacts are dominant. We also compare our results with the offline independent component analysis and artifact subspace reconstruction methods, and show that some local quantities are handled better by our sample-adaptive real-time framework. Decoding performance is also compared with multi-day experimental data from 2 subjects

  4. Real-Time Cellular Analysis Coupled with a Specimen Enrichment Accurately Detects and Quantifies Clostridium difficile Toxins in Stool

    PubMed Central

    Huang, Bin; Jin, Dazhi; Zhang, Jing; Sun, Janet Y.; Wang, Xiaobo; Stiles, Jeffrey; Xu, Xiao; Kamboj, Mini; Babady, N. Esther

    2014-01-01

    We describe here the use of an immunomagnetic separation enrichment process coupled with a modified real-time cellular analysis (RTCA) system (RTCA version 2) for the detection of C. difficile toxin (CDT) in stool. The limit of CDT detection by RTCA version 2 was 0.12 ng/ml. Among the consecutively collected 401 diarrheal stool specimens, 53 (13.2%) were toxin-producing C. difficile strains by quantitative toxigenic culture (qTC); bacterial loads ranged from 3.00 × 101 to 3.69 × 106 CFU/ml. The RTCA version 2 method detected CDT in 51 samples, resulting in a sensitivity of 96.2%, a specificity of 99.7%, and positive and negative predictive values of 98.1% and 99.4%, respectively. The positive step time ranged from 1.43 to 35.85 h, with <24 h for 80% of the samples. The CDT concentrations in stool samples determined by RTCA version 2 correlated with toxigenic C. difficile bacterial load (R2 = 0.554, P = 0.00002) by qTC as well as the threshold cycle (R2 = 0.343, P = 0.014) by real-time PCR. A statistically significant correlation between the CDT concentrations and the clinical severity of CDI was observed (P = 0.015). The sensitivity of the RTCA version 2 assay for the detection of functional toxins in stool specimens was significantly improved when the immunomagnetic separation enrichment process was incorporated. More than 80% positive results can be obtained within 24 h. The stool specimen CDT concentration derived using the RTCA version 2 assay correlates with clinical severity and may be used as a marker for monitoring the status of CDI. PMID:24452160

  5. Real-time cellular analysis coupled with a specimen enrichment accurately detects and quantifies Clostridium difficile toxins in stool.

    PubMed

    Huang, Bin; Jin, Dazhi; Zhang, Jing; Sun, Janet Y; Wang, Xiaobo; Stiles, Jeffrey; Xu, Xiao; Kamboj, Mini; Babady, N Esther; Tang, Yi-Wei

    2014-04-01

    We describe here the use of an immunomagnetic separation enrichment process coupled with a modified real-time cellular analysis (RTCA) system (RTCA version 2) for the detection of C. difficile toxin (CDT) in stool. The limit of CDT detection by RTCA version 2 was 0.12 ng/ml. Among the consecutively collected 401 diarrheal stool specimens, 53 (13.2%) were toxin-producing C. difficile strains by quantitative toxigenic culture (qTC); bacterial loads ranged from 3.00 × 10(1) to 3.69 × 10(6) CFU/ml. The RTCA version 2 method detected CDT in 51 samples, resulting in a sensitivity of 96.2%, a specificity of 99.7%, and positive and negative predictive values of 98.1% and 99.4%, respectively. The positive step time ranged from 1.43 to 35.85 h, with <24 h for 80% of the samples. The CDT concentrations in stool samples determined by RTCA version 2 correlated with toxigenic C. difficile bacterial load (R(2) = 0.554, P = 0.00002) by qTC as well as the threshold cycle (R(2) = 0.343, P = 0.014) by real-time PCR. A statistically significant correlation between the CDT concentrations and the clinical severity of CDI was observed (P = 0.015). The sensitivity of the RTCA version 2 assay for the detection of functional toxins in stool specimens was significantly improved when the immunomagnetic separation enrichment process was incorporated. More than 80% positive results can be obtained within 24 h. The stool specimen CDT concentration derived using the RTCA version 2 assay correlates with clinical severity and may be used as a marker for monitoring the status of CDI. PMID:24452160

  6. Proposed Methods for Real-Time Measurement of Posterior Condylar Angle during TKA

    PubMed Central

    Behera, Prateek; Prakash, Mahesh; Dhillon, Mandeep

    2014-01-01

    Purpose Conventional instruments are known to result in high numbers of outliers in restoring femoral component rotation primarily due to fixed degree of external rotation resection relative to the posterior condylar line (PCL). Outliers can be reduced by determining the patient specific posterior condylar angle (PCA) preoperatively or intraoperatively. There is a paucity of methods that can be used during surgery for determining the PCA. We propose two simple, real-time methods to determine the PCA and hence to measure the axial anatomical variation during surgery. Materials and Methods The study was conducted using axial computed tomography (CT) scans of the knees of 26 patients. The commercial software K-PACS and our proposed two methods (trigonometric and protractor) were used to measure the angle between the transepicondylar axis and PCL, i.e., PCA. Statistical comparison between the mean angles obtained by K-PACS and our methods were done. Results The three methods resulted in similar PCAs. The mean PCA measured by the three methods were similar. The mean PCA value measured by the K-PACS, trigonometric method and protractor method was 6.27° (range, 0° to 12°), 6.23° (range, 0° to 11.11°) and 6.31° (range, 0° to 12°), respectively. There were significant correlations between the K-PACS measured PCA and trigonometrically or protractor measured PCA. Conclusions Our novel, simple, easily reproducible, real-time and radiation-free PCA measurement methods obviate the need for preoperative CT scan for identification of patient specific PCA. PMID:25505705

  7. Real-time measurement of quasiparticle tunneling in a single-junction transmon qubit using feedback

    NASA Astrophysics Data System (ADS)

    Ristè, Diego; Bultink, Niels; Tiggelman, Marijn; Schouten, Raymond; Lehnert, Konrad; Dicarlo, Leonardo

    2013-03-01

    With coherence times of superconducting qubits now exceeding 100 μs , the contribution of quasiparticle (QP) tunneling to qubit relaxation and dephasing becomes potentially relevant. We report the real-time measurement of QP tunneling across the single junction of a 3D transmon qubit. We integrate recent developments in projective qubit readout with 99 % fidelity and feedback-based reset to transform the qubit into a charge-parity detector with 6 μs resolution. We detect a symmetric random telegraph signal matching a QP tunneling time of 0 . 8 ms . By measuring the correlation function of charge parity conditioned on specific initial and final qubit states, we determine that most QP tunneling does not induce qubit transitions, in contradiction with recent theory. We extract a QP-induced qubit relaxation time T1qp ~ 3 ms , decidedly not limiting the measured T1 = 0 . 14 ms . Research supported by NWO, FOM, and EU Project SOLID.

  8. Application of real-time digitization techniques in beam measurement for accelerators

    NASA Astrophysics Data System (ADS)

    Zhao, Lei; Zhan, Lin-Song; Gao, Xing-Shun; Liu, Shu-Bin; An, Qi

    2016-04-01

    Beam measurement is very important for accelerators. In this paper, modern digital beam measurement techniques based on IQ (In-phase & Quadrature-phase) analysis are discussed. Based on this method and high-speed high-resolution analog-to-digital conversion, we have completed three beam measurement electronics systems designed for the China Spallation Neutron Source (CSNS), Shanghai Synchrotron Radiation Facility (SSRF), and Accelerator Driven Sub-critical system (ADS). Core techniques of hardware design and real-time system calibration are discussed, and performance test results of these three instruments are also presented. Supported by National Natural Science Foundation of China (11205153, 10875119), Knowledge Innovation Program of the Chinese Academy of Sciences (KJCX2-YW-N27), and the Fundamental Research Funds for the Central Universities (WK2030040029),and the CAS Center for Excellence in Particle Physics (CCEPP).

  9. Real-time Image Analysis of Living Cellular-Biology Measurements of Intelligent Chemistry

    SciTech Connect

    Solinsky, James C.; Budge, Scott E.; Majors, Paul D.; Rex, Bruce B.

    2003-08-01

    This paper reports on the Pacific Northwest National Laboratory (PNNL) DOE Initiative in Image Science and Technology (ISAT) research, which is developing algorithms and software tool sets for remote sensing and biological applications. In particular, the PNNL ISAT work is applying these research results to the automated analysis of real-time cellular biology imagery to assist the biologist in determining the correct data collection region for the current state of a conglomerate of living cells in three-dimensional motion. The real-time computation of the typical 120 MB/sec multi-spectral data sets is executed in a Field Programmable Gate Array (FPGA) technology, which has very high processing rates due to large-scale parallelism. The outcome of this artificial vision work will allow the biologist to work with imagery as a creditable set of dye-tagged chemistry measurements in formats for individual cell tracking through regional feature extraction, and animation visualization through individual object isolation/characterization of the microscopy imagery.

  10. Adapting CALIPSO Climate Measurements for Near Real Time Analyses and Forecasting

    NASA Technical Reports Server (NTRS)

    Vaughan, Mark A.; Trepte, Charles R.; Winker, David M.; Avery, Melody A.; Campbell, James; Hoff, Ray; Young, Stuart; Getzewich, Brian J.; Tackett, Jason L.; Kar, Jayanta

    2011-01-01

    The Cloud-Aerosol Lidar and Infrared Pathfinder satellite Observations (CALIPSO) mission was originally conceived and designed as a climate measurements mission, with considerable latency between data acquisition and the release of the level 1 and level 2 data products. However, the unique nature of the CALIPSO lidar backscatter profiles quickly led to the qualitative use of CALIPSO?s near real time (i.e., ? expedited?) lidar data imagery in several different forecasting applications. To enable quantitative use of their near real time analyses, the CALIPSO project recently expanded their expedited data catalog to include all of the standard level 1 and level 2 lidar data products. Also included is a new cloud cleared level 1.5 profile product developed for use by operational forecast centers for verification of aerosol predictions. This paper describes the architecture and content of the CALIPSO expedited data products. The fidelity and accuracy of the expedited products are assessed via comparisons to the standard CALIPSO data products.

  11. Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR.

    PubMed

    Balzan, Riccardo; Fernandes, Laetitia; Comment, Arnaud; Pidial, Laetitia; Tavitian, Bertrand; Vasos, Paul R

    2016-01-01

    The main limitation of NMR-based investigations is low sensitivity. This prompts for long acquisition times, thus preventing real-time NMR measurements of metabolic transformations. Hyperpolarization via dissolution DNP circumvents part of the sensitivity issues thanks to the large out-of-equilibrium nuclear magnetization stemming from the electron-to-nucleus spin polarization transfer. The high NMR signal obtained can be used to monitor chemical reactions in real time. The downside of hyperpolarized NMR resides in the limited time window available for signal acquisition, which is usually on the order of the nuclear spin longitudinal relaxation time constant, T1, or, in favorable cases, on the order of the relaxation time constant associated with the singlet-state of coupled nuclei, TLLS. Cellular uptake of endogenous molecules and metabolic rates can provide essential information on tumor development and drug response. Numerous previous hyperpolarized NMR studies have demonstrated the relevancy of pyruvate as a metabolic substrate for monitoring enzymatic activity in vivo. This work provides a detailed description of the experimental setup and methods required for the study of enzymatic reactions, in particular the pyruvate-to-lactate conversion rate in presence of lactate dehydrogenase (LDH), by hyperpolarized NMR. PMID:26967906

  12. Real-time dual-loop electric current measurement for label-free nanofluidic preconcentration chip.

    PubMed

    Chung, Pei-Shan; Fan, Yu-Jui; Sheen, Horn-Jiunn; Tian, Wei-Cheng

    2015-01-01

    An electrokinetic trapping (EKT)-based nanofluidic preconcentration device with the capability of label-free monitoring trapped biomolecules through real-time dual-loop electric current measurement was demonstrated. Universal current-voltage (I-V) curves of EKT-based preconcentration devices, consisting of two microchannels connected by ion-selective channels, are presented for functional validation and optimal operation; universal onset current curves indicating the appearance of the EKT mechanism serve as a confirmation of the concentrating action. The EKT mechanism and the dissimilarity in the current curves related to the volume flow rate (Q), diffusion coefficient (D), and diffusion layer (DL) thickness were explained by a control volume model with a five-stage preconcentration process. Different behaviors of the trapped molecular plug were categorized based on four modes associated with different degrees of electroosmotic instability (EOI). A label-free approach to preconcentrating (bio)molecules and monitoring the multibehavior molecular plug was demonstrated through real-time electric current monitoring, rather than through the use of microscope images. PMID:25372369

  13. Real-Time Protein and Cell Binding Measurements on Hydroxyapatite Coatings.

    PubMed

    Vilardell, A M; Cinca, N; Jokinen, A; Garcia-Giralt, N; Dosta, S; Cano, I G; Guilemany, J M

    2016-01-01

    Although a lot of in vitro and in vivo assays have been performed during the last few decades years for hydroxyapatite bioactive coatings, there is a lack of exploitation of real-time in vitro interaction measurements. In the present work, real-time interactions for a plasma sprayed hydroxyapatite coating were measured by a Multi-Parametric Surface Plasmon Resonance (MP-SPR), and the results were compared with standard traditional cell viability in vitro assays. MP-SPR is proven to be suitable not only for measurement of molecule-molecule interactions but also molecule-material interaction measurements and cell interaction. Although SPR is extensively utilized in interaction studies, recent research of protein or cell adsorption on hydroxyapatite coatings for prostheses applications was not found. The as-sprayed hydroxyapatite coating resulted in 62.4% of crystalline phase and an average thickness of 24 ± 6 μm. The MP-SPR was used to measure lysozyme protein and human mesenchymal stem cells interaction to the hydroxyapatite coating. A comparison between the standard gold sensor and Hydroxyapatite (HA)-plasma coated sensor denoted a clearly favourable cell attachment on HA coated sensor as a significantly higher signal of cell binding was detected. Moreover, traditional cell viability and proliferation tests showed increased activity with culture time indicating that cells were proliferating on HA coating. Cells show homogeneous distribution and proliferation along the HA surface between one and seven days with no significant mortality. Cells were flattened and spread on rough surfaces from the first day, with increasing cytoplasmatic extensions during the culture time. PMID:27618911

  14. Real-time dielectric-film thickness measurement system for plasma processing chamber wall monitoring

    NASA Astrophysics Data System (ADS)

    Kim, Jin-Yong; Chung, Chin-Wook

    2015-12-01

    An in-situ real-time processing chamber wall monitoring system was developed. In order to measure the thickness of the dielectric film, two frequencies of small sinusoidal voltage (˜1 V) signals were applied to an electrically floated planar type probe, which is positioned at chamber wall surface, and the amplitudes of the currents and the phase differences between the voltage and current were measured. By using an equivalent sheath circuit model including a sheath capacitance, the dielectric thickness can be obtained. Experiments were performed in various plasma condition, and reliable dielectric film thickness was obtained regardless of the plasma properties. In addition, availability in commercial chamber for plasma enhanced chemical vapor deposition was verified. This study is expected to contribute to the control of etching and deposition processes and optimization of periodic maintenance in semiconductor manufacturing process.

  15. Performance modeling and measurement of real-time multiprocessors with time-shared buses

    SciTech Connect

    Woodbury, M.H.; Shin, K.G.

    1988-02-01

    A closed queueing network model is constructed to address workload effects on computer performance for a highly reliable unibus multiprocessor used in real-time control. The queueing model consists of multiserver nodes and a nonpreemptive priority queue. Use of this model requires partitioning the workload into task classes. The time average steady-state solution of the queuing model directly produces useful results that are necessary in performance evaluation. The model is experimentally justified with the Fault-Tolerant Multiprocessor (FTMP) located at the NASA AIRLAB. Extensive experiments are performed on FTMP with a synthetic workload generator (SWG) to directly measure performance parameters, such as processor idle time, system bus contention, and task processing times. These measurements determine values for parameters in the queueing model. Experimental and analytic results are then compared.

  16. Traffic dynamics: Method for estimating freeway travel times in real time from flow measurements

    SciTech Connect

    Nam, D.H.; Drew, D.R.

    1996-05-01

    This paper presents a method for estimating freeway travel times in real time directly from flow measurements, which is desirable for present and future Intelligent Vehicle-Highway Systems (IVHS) applications. An inductive modeling approach adapted here is based on stochastic queuing theory and the principle of conservation of vehicles. The analytical expression for link travel times satisfies traffic dynamics where the new form of the conservation of vehicles has been derived under generalized traffic conditions. A computer program has been developed to implement the algorithm. Analysis results show that the estimates have good agreement with empirical data measured at 30-s intervals. This methodology has potential applicable to automatic traffic control and automatic incident detection.

  17. A Real-Time Optical Tracking and Measurement Processing System for Flying Targets

    PubMed Central

    Guo, Pengyu; Ding, Shaowen; Zhang, Hongliang; Zhang, Xiaohu

    2014-01-01

    Optical tracking and measurement for flying targets is unlike the close range photography under a controllable observation environment, which brings extreme conditions like diverse target changes as a result of high maneuver ability and long cruising range. This paper first designed and realized a distributed image interpretation and measurement processing system to achieve resource centralized management, multisite simultaneous interpretation and adaptive estimation algorithm selection; then proposed a real-time interpretation method which contains automatic foreground detection, online target tracking, multiple features location, and human guidance. An experiment is carried out at performance and efficiency evaluation of the method by semisynthetic video. The system can be used in the field of aerospace tests like target analysis including dynamic parameter, transient states, and optical physics characteristics, with security control. PMID:24987748

  18. A real-time optical tracking and measurement processing system for flying targets.

    PubMed

    Guo, Pengyu; Ding, Shaowen; Zhang, Hongliang; Zhang, Xiaohu

    2014-01-01

    Optical tracking and measurement for flying targets is unlike the close range photography under a controllable observation environment, which brings extreme conditions like diverse target changes as a result of high maneuver ability and long cruising range. This paper first designed and realized a distributed image interpretation and measurement processing system to achieve resource centralized management, multisite simultaneous interpretation and adaptive estimation algorithm selection; then proposed a real-time interpretation method which contains automatic foreground detection, online target tracking, multiple features location, and human guidance. An experiment is carried out at performance and efficiency evaluation of the method by semisynthetic video. The system can be used in the field of aerospace tests like target analysis including dynamic parameter, transient states, and optical physics characteristics, with security control. PMID:24987748

  19. Real-time measurement of sub-PPM concentrations of airborne chemicals in semiconductor manufacturing.

    PubMed

    Corn, M; Cohen, R

    1993-01-01

    Real-time mass spectroscopy (ICAMS) can provide hourly or daily estimates of employee exposure. Field calibration of the unit indicated essentially linear response from 0.01 (Cellosolve Acetate) and 0.03 ppm (Diglyme) to 1 ppm in semiconductor cleanrooms. The instrument can be programmed for 4 minute readings on a single compound, or for rotation among several chemicals, each requiring 4 minute dwell times for analysis. In contrast to full shift personal sampling methods to measure exposure, ICAMS offers insights into the occurrence of peak exposures. In addition, in the occupational environment ICAMS results can be integrated to estimate full-shift within a zone exposures. Thus, the ICAMS extends measurement sensitivities below those currently available and offers a viable alternative to personal sampling in the semiconductor industry. PMID:9857292

  20. (abstract) Using GPS Measurements to Identify Global Ionospheric Storms in Near Real-Time

    NASA Technical Reports Server (NTRS)

    Ho, C. M.; Mannucci, A. J.; Lindqwister, U. J.; Rao, A. M.; Pi, X.; Wilson, B. D.; Yuan, D. N.; Reyes, M.

    1996-01-01

    The solar wind interacts with the Earth's magnetosphere, eventually dissipating energy into the ionosphere and atmosphere. As a terminator, the ionosphere responds to magnetic storms, which is very important in understanding the energy coupling process between the Sun and the Earth and in forecasting space weather changes.The worldwide GPS network, for the first time, makes near real-time global ionospheric TEC measurements a possibility. Based on these measurements, global ionospheric TEC maps are generated with time resolution of from 5 minutes to hours. Using these maps, we can analyze the global evolution of ionospheric storms on temporal and spatial scales, which have been dificult to study before. We find that for certain types of storms (such as TID-driven), it is possible to identify them near onset and issue warning signals during the early stages. Main attention has been paid on northern hemispheric winter storms. Their common features and physical mechanisms are being investigated.

  1. High-resolution micromechanical measurement in real time of forces exerted by living cells

    PubMed Central

    Swierczewski, Robert; Hedley, John; Redfern, Chris P. F.

    2016-01-01

    ABSTRACT The aim of this study was to compare uniaxial traction forces exerted by different cell types using a novel sensor design and to test the dependence of measured forces on cytoskeletal integrity. The sensor design detects forces generated between 2 contact points by cells spanning a gap. The magnitude of these forces varied according to cell type and were dependent on cytoskeletal integrity. The response time for drug-induced cytoskeletal disruption also varied between cell types: dermal fibroblasts exerted the greatest forces and had the slowest drug response times; EBV-transformed epithelial cells also had slow cytoskeletal depolymerisation times but exerted the lowest forces overall. Conversely, lung epithelial tumor cells exerted low forces but had the fastest depolymerisation drug response. These results provide proof of principle for a new design of force-measurement sensor based on optical interferometry, an approach that can be used to study cytoskeletal dynamics in real time. PMID:26645140

  2. Real-time HF Radio Absorption Maps Incorporating Riometer and Satellite Measurements

    NASA Astrophysics Data System (ADS)

    Rogers, Neil; Honary, Farideh; Warrington, Mike; Stocker, Alan; Danskin, Donald

    2016-04-01

    A real-time model of HF radio propagation conditions is being developed as a service for aircraft communications at high latitudes. An essential component of this is a real-time map of the absorption of HF (3-30 MHz) radio signals in the D-region ionosphere. Empirical, climatological Polar Cap Absorption (PCA) models in common usage cannot account for day-to-day variations in ionospheric composition and are inaccurate during the large changes in recombination rate at twilight. However, parameters of such models may be optimised using an age-weighted regression to absorption measurements from riometers in Canada and Scandinavia. Such parameters include the day- and night-time sensitivity to proton flux as measured on a geostationary satellite (GOES). Modelling the twilight transition as a linear or Gauss error function over a range of solar-zenith angles (χl < χ < χu) is found to provide greater accuracy than 'Earth shadow' methods (as applied in the Sodankylä Ionospheric Chemistry (SIC) model, for example) due to a more gradual ionospheric response for χ < 90° . The fitted χl parameter is found to be most variable, with smaller values (as low as 60°) post-sunrise compared with pre-sunset. Correlation coefficients of model parameters between riometers are presented and these provide a means of appropriately weighting individual riometer contributions in an assimilative PCA model. At times outside of PCA events, the probability of absorption in the auroral zones is related to the energetic electron flux inside the precipitation loss cone, as measured on the polar-orbiting POES satellites. This varies with magnetic local time, magnetic latitude and geomagnetic activity, and its relation to the real-time solar wind - magnetospheric coupling function [Newell et al., 2007] will be presented. Reference: Newell, P. T., T. Sotirelis, K. Liou, C.-I. Meng, and F. J. Rich (2007), A nearly universal solar wind-magnetosphere coupling function inferred from 10

  3. Measuring Sea-Ice Motion in the Arctic with Real Time Photogrammetry

    NASA Astrophysics Data System (ADS)

    Brozena, J. M.; Hagen, R. A.; Peters, M. F.; Liang, R.; Ball, D.

    2014-12-01

    The U.S. Naval Research Laboratory, in coordination with other groups, has been collecting sea-ice data in the Arctic off the north coast of Alaska with an airborne system employing a radar altimeter, LiDAR and a photogrammetric camera in an effort to obtain wide swaths of measurements coincident with Cryosat-2 footprints. Because the satellite tracks traverse areas of moving pack ice, precise real-time estimates of the ice motion are needed to fly a survey grid that will yield complete data coverage. This requirement led us to develop a method to find the ice motion from the aircraft during the survey. With the advent of real-time orthographic photogrammetric systems, we developed a system that measures the sea ice motion in-flight, and also permits post-process modeling of sea ice velocities to correct the positioning of radar and LiDAR data. For the 2013 and 2014 field seasons, we used this Real Time Ice Motion Estimation (RTIME) system to determine ice motion using Applanix's Inflight Ortho software with an Applanix DSS439 system. Operationally, a series of photos were taken in the survey area. The aircraft then turned around and took more photos along the same line several minutes later. Orthophotos were generated within minutes of collection and evaluated by custom software to find photo footprints and potential overlap. Overlapping photos were passed to the correlation software, which selects a series of "chips" in the first photo and looks for the best matches in the second photo. The correlation results are then passed to a density-based clustering algorithm to determine the offset of the photo pair. To investigate any systematic errors in the photogrammetry, we flew several flight lines over a fixed point on various headings, over an area of non-moving ice in 2013. The orthophotos were run through the correlation software to find any residual offsets, and run through additional software to measure chip positions and offsets relative to the aircraft

  4. Mitochondrial DNA as a non-invasive biomarker: Accurate quantification using real time quantitative PCR without co-amplification of pseudogenes and dilution bias

    SciTech Connect

    Malik, Afshan N.; Shahni, Rojeen; Rodriguez-de-Ledesma, Ana; Laftah, Abas; Cunningham, Phil

    2011-08-19

    Highlights: {yields} Mitochondrial dysfunction is central to many diseases of oxidative stress. {yields} 95% of the mitochondrial genome is duplicated in the nuclear genome. {yields} Dilution of untreated genomic DNA leads to dilution bias. {yields} Unique primers and template pretreatment are needed to accurately measure mitochondrial DNA content. -- Abstract: Circulating mitochondrial DNA (MtDNA) is a potential non-invasive biomarker of cellular mitochondrial dysfunction, the latter known to be central to a wide range of human diseases. Changes in MtDNA are usually determined by quantification of MtDNA relative to nuclear DNA (Mt/N) using real time quantitative PCR. We propose that the methodology for measuring Mt/N needs to be improved and we have identified that current methods have at least one of the following three problems: (1) As much of the mitochondrial genome is duplicated in the nuclear genome, many commonly used MtDNA primers co-amplify homologous pseudogenes found in the nuclear genome; (2) use of regions from genes such as {beta}-actin and 18S rRNA which are repetitive and/or highly variable for qPCR of the nuclear genome leads to errors; and (3) the size difference of mitochondrial and nuclear genomes cause a 'dilution bias' when template DNA is diluted. We describe a PCR-based method using unique regions in the human mitochondrial genome not duplicated in the nuclear genome; unique single copy region in the nuclear genome and template treatment to remove dilution bias, to accurately quantify MtDNA from human samples.

  5. Endothelial cell adhesion in real time. Measurements in vitro by tandem scanning confocal image analysis.

    PubMed

    Davies, P F; Robotewskyj, A; Griem, M L

    1993-06-01

    Real time measurements of cell-substratum adhesion in endothelial cells were obtained by tandem scanning confocal microscopy of sites of focal contact (focal adhesions) at the abluminal cell surface. Focal contact sites were sharply defined (low radiance levels) in the living cell such that the images could be enhanced, digitized, and isolated from other cellular detail. Sites of focal contact are the principal determinant of cell-substratum adhesion. Measurements of (a) the focal contact area and (b) the closeness of contact (inverse radiance) were used to nominally define the adhesion of a single cell or field of cells, and to record spontaneous and induced changes of cell adhesion in real time. The topography of focal contacts was estimated by calculating separation distances from radiance values using a calibration technique based on interference ring optics. While slightly closer contact was noted between the cell membrane and substratum at or near the center of each focal contact, separation distances throughout the adhesion regions were always < 50 nm. Subtraction of consecutive images revealed continuous spontaneous remodeling of individual focal adhesions in unperturbed cells during periods of < 1 min. Despite extensive remodeling of focal contact sites, however, cell adhesion calculated for an entire cell over extended periods varied by < 10%. When cytoskeletal stability was impaired by exposure to cytochalasin or when cells were exposed to proteolytic enzyme, endothelial adhesion declined rapidly. Such changes were recorded at the level of single cells, groups of cells, and at single focal adhesions. In both unperturbed and manipulated cells, the dynamics of remodeling and cell adhesion characteristics varied greatly between individual sites within the same cell; disappearance of existing sites and appearance of new ones often occurred within minutes while adjacent sites underwent minimal remodelling. Tandem scanning confocal microscopy image analysis of

  6. Real-Time Unsteady Loads Measurements Using Hot-Film Sensors

    NASA Technical Reports Server (NTRS)

    Mangalam, Arun S.; Moes, Timothy R.

    2004-01-01

    Several flight-critical aerodynamic problems such as buffet, flutter, stall, and wing rock are strongly affected or caused by abrupt changes in unsteady aerodynamic loads and moments. Advanced sensing and flow diagnostic techniques have made possible simultaneous identification and tracking, in realtime, of the critical surface, viscosity-related aerodynamic phenomena under both steady and unsteady flight conditions. The wind tunnel study reported here correlates surface hot-film measurements of leading edge stagnation point and separation point, with unsteady aerodynamic loads on a NACA 0015 airfoil. Lift predicted from the correlation model matches lift obtained from pressure sensors for an airfoil undergoing harmonic pitchup and pitchdown motions. An analytical model was developed that demonstrates expected stall trends for pitchup and pitchdown motions. This report demonstrates an ability to obtain unsteady aerodynamic loads in real time, which could lead to advances in air vehicle safety, performance, ride-quality, control, and health management.

  7. Applications of Kalman filtering to real-time trace gas concentration measurements

    NASA Technical Reports Server (NTRS)

    Leleux, D. P.; Claps, R.; Chen, W.; Tittel, F. K.; Harman, T. L.

    2002-01-01

    A Kalman filtering technique is applied to the simultaneous detection of NH3 and CO2 with a diode-laser-based sensor operating at 1.53 micrometers. This technique is developed for improving the sensitivity and precision of trace gas concentration levels based on direct overtone laser absorption spectroscopy in the presence of various sensor noise sources. Filter performance is demonstrated to be adaptive to real-time noise and data statistics. Additionally, filter operation is successfully performed with dynamic ranges differing by three orders of magnitude. Details of Kalman filter theory applied to the acquired spectroscopic data are discussed. The effectiveness of this technique is evaluated by performing NH3 and CO2 concentration measurements and utilizing it to monitor varying ammonia and carbon dioxide levels in a bioreactor for water reprocessing, located at the NASA-Johnson Space Center. Results indicate a sensitivity enhancement of six times, in terms of improved minimum detectable absorption by the gas sensor.

  8. Instrument Development of Real Time Holographic Water Drop Size Measurement System

    SciTech Connect

    Springston, Stephen

    2007-02-09

    BNL participated with multiple correspondences with Physical Optics Corporation (POC) on the design considerations of an airbome instrument. A pod for extemal deployment ofthe POC unit on the DOE Research Aircraft Facility (RAF), an instrumented, Grumman G-1 aircraft was loaned to POC. BNL proposed evaluation flight tests between the POC unit and the BNL Cloud Aerosol Probe Spectrometer (CAPS) as a reference method. BNL's involvement is described in the semi-annual report ofPOC to DOE. Because of unanticipated technical and engineering difficulties, POC was unable to fit their instrument into an aircraft pod. As a result they are now focusing on a ground-based version first. A prototype laboratory version of the Real-Time Holographic Water Drop Size Measurement (WDSM) System has been constructed.

  9. Real-time reflectometry measurement validation in H-mode regimes for plasma position control.

    PubMed

    Santos, J; Guimarais, L; Manso, M

    2010-10-01

    It has been shown that in H-mode regimes, reflectometry electron density profiles and an estimate for the density at the separatrix can be jointly used to track the separatrix within the precision required for plasma position control on ITER. We present a method to automatically remove, from the position estimation procedure, measurements performed during collapse and recovery phases of edge localized modes (ELMs). Based on the rejection mechanism, the method also produces an estimate confidence value to be fed to the position feedback controller. Preliminary results show that the method improves the real-time experimental separatrix tracking capabilities and has the potential to eliminate the need for an external online source of ELM event signaling during control feedback operation. PMID:21061481

  10. Prediction of solar energetic particle event histories using real-time particle and solar wind measurements

    NASA Technical Reports Server (NTRS)

    Roelof, E. C.; Gold, R. E.

    1978-01-01

    The comparatively well-ordered magnetic structure in the solar corona during the decline of Solar Cycle 20 revealed a characteristic dependence of solar energetic particle injection upon heliographic longitude. When analyzed using solar wind mapping of the large scale interplanetary magnetic field line connection from the corona to the Earth, particle fluxes display an approximately exponential dependence on heliographic longitude. Since variations in the solar wind velocity (and hence the coronal connection longitude) can severely distort the simple coronal injection profile, the use of real-time solar wind velocity measurements can be of great aid in predicting the decay of solar particle events. Although such exponential injection profiles are commonplace during 1973-1975, they have also been identified earlier in Solar Cycle 20, and hence this structure may be present during the rise and maximum of the cycle, but somewhat obscured by greater temporal variations in particle injection.

  11. Real-time measurements of endogenous CO production from vascular cells using an ultrasensitive laser sensor

    NASA Technical Reports Server (NTRS)

    Morimoto, Y.; Durante, W.; Lancaster, D. G.; Klattenhoff, J.; Tittel, F. K.

    2001-01-01

    Carbon monoxide (CO) has been implicated as a biological messenger molecule analogous to nitric oxide. A compact gas sensor based on a midinfrared laser absorption spectroscopy was developed for direct and real-time measurement of trace levels (in approximate pmol) of CO release by vascular cells. The midinfrared light is generated by difference frequency mixing of two nearinfrared lasers in a nonlinear optical crystal. A strong infrared absorption line of CO (4.61 microm) is chosen for convenient CO detection without interference from other gas species. The generation of CO from cultured vascular smooth muscle cells was detected every 20 s without any chemical modification to the CO. The sensitivity of the sensor reached 6.9 pmol CO. CO synthesis was measured from untreated control cells (0.25 nmol per 10(7) cells/h), sodium nitroprusside-treated cells (0.29 nmol per 10(7) cells/h), and hemin-treated cells (0.49 nmol per 10(7) cells/h). The sensor also detected decreases in CO production after the addition of the heme oxygenase (HO) inhibitor tin protoporphyrin-IX (from 0.49 to 0.02 nmol per 10(7) cells/h) and increases after the administration of the HO substrate hemin (from 0.27 to 0.64 nmol per 10(7) cells/h). These results demonstrate that midinfrared laser absorption spectroscopy is a useful technique for the noninvasive and real-time detection of trace levels of CO from biological tissues.

  12. Real-time measurements of endogenous CO production from vascular cells using an ultrasensitive laser sensor.

    PubMed

    Morimoto, Y; Durante, W; Lancaster, D G; Klattenhoff, J; Tittel, F K

    2001-01-01

    Carbon monoxide (CO) has been implicated as a biological messenger molecule analogous to nitric oxide. A compact gas sensor based on a midinfrared laser absorption spectroscopy was developed for direct and real-time measurement of trace levels (in approximate pmol) of CO release by vascular cells. The midinfrared light is generated by difference frequency mixing of two nearinfrared lasers in a nonlinear optical crystal. A strong infrared absorption line of CO (4.61 microm) is chosen for convenient CO detection without interference from other gas species. The generation of CO from cultured vascular smooth muscle cells was detected every 20 s without any chemical modification to the CO. The sensitivity of the sensor reached 6.9 pmol CO. CO synthesis was measured from untreated control cells (0.25 nmol per 10(7) cells/h), sodium nitroprusside-treated cells (0.29 nmol per 10(7) cells/h), and hemin-treated cells (0.49 nmol per 10(7) cells/h). The sensor also detected decreases in CO production after the addition of the heme oxygenase (HO) inhibitor tin protoporphyrin-IX (from 0.49 to 0.02 nmol per 10(7) cells/h) and increases after the administration of the HO substrate hemin (from 0.27 to 0.64 nmol per 10(7) cells/h). These results demonstrate that midinfrared laser absorption spectroscopy is a useful technique for the noninvasive and real-time detection of trace levels of CO from biological tissues. PMID:11123266

  13. Development of an equipment for real time MTF measurement of optical systems

    NASA Astrophysics Data System (ADS)

    Romano, Dimas Rodrigues; de Almeida Nobre, Sergio Antonio; de Albuquerque, Bráulio Fonseca Carneiro

    2008-04-01

    The quality of optical systems concerning contrast and resolution can be quantified through the use of the modulation transfer function (MTF) analysis. This metrology method can give us information about how much contrast is lost when light traverses an optical system for each spatial frequency until the cutoff, or Nyquist frequency. In this work is presented a procedure based on the measurement of a knife edge target from which one can extract the line spread function and, as a consequence, the optical transfer function needed to the MTF analysis. We used in the analysis a least square algorithm to fit the experimental data of the edge spread function and a FFT algorithm to extract the optical transfer function from the line spread function of the measured system. It is of great interest to apply this metrology analysis directly in lens production in order to have real measurements of quality for the optical components as they are manufactured. With this objective in mind we developed a MTF measurement equipment and we will talk about the difficulties involved, and its general characteristics. The main characteristic of our measurement equipment is the possibility of real time measurements, important in the fast quality control assurance needed in lens production.

  14. Real-time measurement of materials properties at high temperatures by laser produced plasmas

    NASA Technical Reports Server (NTRS)

    Kim, Yong W.

    1990-01-01

    Determination of elemental composition and thermophysical properties of materials at high temperatures, as visualized in the context of containerless materials processing in a microgravity environment, presents a variety of unusual requirements owing to the thermal hazards and interferences from electromagnetic control fields. In addition, such information is intended for process control applications and thus the measurements must be real time in nature. A new technique is described which was developed for real time, in-situ determination of the elemental composition of molten metallic alloys such as specialty steel. The technique is based on time-resolved spectroscopy of a laser produced plasma (LPP) plume resulting from the interaction of a giant laser pulse with a material target. The sensitivity and precision were demonstrated to be comparable to, or better than, the conventional methods of analysis which are applicable only to post-mortem specimens sampled from a molten metal pool. The LPP technique can be applied widely to other materials composition analysis applications. The LPP technique is extremely information rich and therefore provides opportunities for extracting other physical properties in addition to the materials composition. The case in point is that it is possible to determine thermophysical properties of the target materials at high temperatures by monitoring generation and transport of acoustic pulses as well as a number of other fluid-dynamic processes triggered by the LPP event. By manipulation of the scaling properties of the laser-matter interaction, many different kinds of flow events, ranging from shock waves to surface waves to flow induced instabilities, can be generated in a controllable manner. Time-resolved detection of these events can lead to such thermophysical quantities as volume and shear viscosities, thermal conductivity, specific heat, mass density, and others.

  15. Environmental measurement while drilling system for real-time field screening of contaminants

    SciTech Connect

    Williams, C.V.; Lockwood, G.J.; Normann, R.A.

    1996-12-31

    Sampling during environmental drilling is essential to fully characterize the spatial distribution and migration of subsurface contaminants. Real-time information on environmental conditions, drill bit location and temperature during drilling is valuable in many environmental restoration operations. This type of information can be used to provide field screening data and improved efficiency of site characterization activities. The Environmental Measurement-While-Drilling (EMWD) System represents an innovative blending of new and existing technology in order to obtain real-time data during drilling. The system consists of two subsystems. The down-hole subsystem (at the drill bit) consists of sensors, a power supply, a signal conditioning and transmitter board, and a radio-frequency (RF) coaxial cable. The up-hole subsystem consists of a battery pack/coil, pickup coil, receiver, and personal computer. The system is compatible with fluid miser drill pipe, a directional drilling technique that uses minimal drilling fluids and generates little to no secondary waste. In EMWD, downhole sensors are located behind the drill bit and linked by a high-speed data transmission system to a computer at the surface. As drilling is conducted, data is collected on the nature and extent of contamination, enabling on-the-spot decisions regarding drilling and sampling strategies. Initially, the downhole sensor consisted of a simple gamma radiation detector, a Geiger-Mueller tube (GMT). The EMWD system has been improved by the integration of a Gamma Ray Spectrometer (GRS) in place of the GMT. The GRS consists of a sodium iodide-thallium activated crystal coupled to a photomultiplier tube (PMT). The output of the PMT goes to a multichannel analyzer (MCA). The MCA data is transmitted to the surface via a signal conditioning and transmitter board similar to that used with the GMT. The EMWD system is described and the results of the GRS field tests and field demonstration are presented.

  16. Best Practice for Rainfall Measurement, Torrential Flood Monitoring and Real Time Alerting System in Serbia

    NASA Astrophysics Data System (ADS)

    Stefanovic, Milutin; Milojevic, Mileta; Zlatanovic, Nikola

    2014-05-01

    Serbia occupies 88.000 km2 and its confined zone menaced with torrent flood occupies 50.000km2. Floods on large rivers and torrents are the most frequent natural disasters in Serbia. This is the result of a geographic position and relief of Serbia. Therefore, defense from these natural disasters has been institutionalized since the 19th century. Through its specialized bodies and public companies, the State organized defense from floods on large rivers and protection of international and other main roads. The Topčiderska River is one of a number of rivers in Serbia that is a threat to both urban and rural environments. In this text, general characteristics of this river will be illustrated, as well as the historical natural hazards that have occurred in the part of Belgrade near Topčiderska River. Belgrade is the capital of Serbia, its political, administrative and financial center, which means that there are significant financial capacities and human resources for investments in all sectors, and specially in the water resources sector. Along the Topčiderska catchment there are many industrial, traffic and residential structures that are in danger of floods and flood protection is more difficult with rapid high flows. The goal is to use monitoring on the Topčiderska River basin to set up a modern system for monitoring in real time and forecast of torrential floods. This paper represents a system of remote detection and monitoring of torrential floods and rain measurements in real time on Topciderka river and ready for a quick response.

  17. A new system for measurement of low frequency radio transmitting antenna parameters in near real time

    NASA Astrophysics Data System (ADS)

    Tietsworth, S. C.

    1991-06-01

    Fixed site very low frequency (VLF) and low frequency (LF) transmit antenna systems are used as the primary means of communication to submarine at sea. Until now there has not been a system to measure important antenna parameters on these low frequency transmit antennas in near real time while the antenna is being driven by frequency shift modulation. This paper describes a new system which can be used to measure several important antenna and tuning system parameters on these transmit antennas while the antennas are in normal operation. The measurements are made by sampling and processing the antenna voltage and current signals to calculate the antenna system resistance, capacitance, inductance, voltage, current and power which can then be displayed and stored on a personal computer. All of these measurements are made while the antenna is being driven by FSK or MSK signals. The paper includes a model of a typical low frequency transmit antenna as well as the associated equations. The response of the antenna system to frequency shift keying signals is then presented. In addition, the algorithms, hardware, and software used by the measurement system, called the VLF/LF antenna monitor system (AMOS), are discussed along with a summary of results obtained during initial testing of the AMOS system.

  18. Real-time Accurate Surface Reconstruction Pipeline for Vision Guided Planetary Exploration Using Unmanned Ground and Aerial Vehicles

    NASA Technical Reports Server (NTRS)

    Almeida, Eduardo DeBrito

    2012-01-01

    This report discusses work completed over the summer at the Jet Propulsion Laboratory (JPL), California Institute of Technology. A system is presented to guide ground or aerial unmanned robots using computer vision. The system performs accurate camera calibration, camera pose refinement and surface extraction from images collected by a camera mounted on the vehicle. The application motivating the research is planetary exploration and the vehicles are typically rovers or unmanned aerial vehicles. The information extracted from imagery is used primarily for navigation, as robot location is the same as the camera location and the surfaces represent the terrain that rovers traverse. The processed information must be very accurate and acquired very fast in order to be useful in practice. The main challenge being addressed by this project is to achieve high estimation accuracy and high computation speed simultaneously, a difficult task due to many technical reasons.

  19. Continuous-flow water sampler for real-time isotopic water measurements

    NASA Astrophysics Data System (ADS)

    Carter, J.; Dennis, K.

    2013-12-01

    Measuring the stable isotopes of liquid water (δ18O and δD) is a tool familiar to many Earth scientists, but most current techniques require discrete sampling. For example, isotope ratio mass spectrometry requires the collection of aliquots of water that are then converted to CO2, CO or H2 for analysis. Similarly, laser-based techniques, such as Cavity Ring-Down Spectroscopy (CRDS) convert discrete samples (typically < 2μL) of liquid water to water vapor using a flash vaporization process. By requiring the use of discrete samples fine-scale spatial and temporal studies of changes in δ18O and δD are limited. Here we present a continuous-flow water sampler that will enable scientists to probe isotopic changes in real-time, with applications including, but not limited to, quantification of the 'amount effect' (Dansgaard, 1964) during an individual precipitation event or storm track, real-time mixing of water in river systems, and shipboard continuous water measurements (Munksgaard et al., 2012). Due to the inherent ability of CRDS to measure a continuous flow of water vapor it is an ideal candidate for interfacing with a continuous water sampling system. Here we present results from the first commercially available continuous-flow water sampler, developed by engineers at Picarro. This peripheral device is compatible with Picarro CRDS isotopic water analyzers, allowing real-time, continuous isotopic measurements of liquid water. The new device, which expands upon the design of Munskgaard et al. (2011), utilizes expanded polytetrafluoroethylene (ePTFE) membrane technology to continuously generate gas-phase water, while liquid water is pumped through the system. The water vapor subsequently travels to the CRDS analyzer where the isotopic ratios are measured and recorded. The generation of water vapor using membrane technology is sensitive to environmental conditions, which if not actively control, lead to sustainable experimental noise and drift. Consequently, our

  20. Hilbert phase dynamometry (HPD) for real-time measurement of cell generated forces (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Sridharan, Shamira; Li, Yanfen; Bhaduri, Basanta; Majeed, Hassaan; Dupenloup, Paul; Levine, Alex; Kilian, Kristopher A.; Popescu, Gabriel

    2016-03-01

    Traction force microscopy is the most widely used technique for studying the forces exerted by cells on deformable substrates. However, the method is computationally intense and cells have to be detached from the substrate prior to measuring the displacement map. We have developed a new method, referred to as Hilbert phase dynamometry (HPD), which yields real-time force fields and, simultaneously, cell dry mass and growth information. HPD operates by imaging cells on a deformable substrate that is patterned with a grid of fluorescent proteins. A Hilbert transform is used to extract the phase map associated with the grid deformation, which provides the displacement field. By combining this information with substrate stiffness, an elasticity model was developed to measure forces exerted by cells with high spatial resolution. In our study, we prepared 10kPa gels and them with a 2-D grid of FITC-conjugated fibrinogen/fibronectin mixture, an extracellular matrix protein to which cells adhere. We cultured undifferentiated mesenchymal stem cells (MSC), and MSCs that were in the process of undergoing adipogenesis and osteogenesis. The cells were measured over the course of 24 hours using Spatial Light Interference Microscopy (SLIM) and wide-field epi-fluorescence microscopy allowing us to simultaneously measure cell growth and the forces exerted by the cells on the substrate.

  1. In-Line Capacitance Sensor for Real-Time Water Absorption Measurements

    NASA Technical Reports Server (NTRS)

    Nurge, Mark A.; Perusich, Stephen A.

    2010-01-01

    A capacitance/dielectric sensor was designed, constructed, and used to measure in real time the in-situ water concentration in a desiccant water bed. Measurements were carried out with two experimental setups: (1) passing nitrogen through a humidity generator and allowing the gas stream to become saturated at a measured temperature and pressure, and (2) injecting water via a syringe pump into a nitrogen stream. Both water vapor generating devices were attached to a downstream vertically-mounted water capture bed filled with 19.5 g of Moisture Gone desiccant. The sensor consisted of two electrodes: (1) a 1/8" dia stainless steel rod placed in the middle of the bed and (2) the outer shell of the stainless steel bed concentric with the rod. All phases of the water capture process (background, heating, absorption, desorption, and cooling) were monitored with capacitance. The measured capacitance was found to vary linearly with the water content in the bed at frequencies above 100 kHz indicating dipolar motion dominated the signal; below this frequency, ionic motion caused nonlinearities in the water concentration/capacitance relationship. The desiccant exhibited a dielectric relaxation whose activation energy was lowered upon addition of water indicating either a less hindered rotational motion or crystal reorientation.

  2. Real-time thickness measurement of biological tissues using a microfabricated magnetically-driven lens actuator.

    PubMed

    Mansoor, Hadi; Zeng, Haishan; Chiao, Mu

    2011-08-01

    A fiber optic confocal catheter with a micro scanning lens was developed for real-time and non-contact thickness measurement of biological tissue. The catheter has an outer diameter and rigid length of 4.75 mm and 30 mm respectively and is suitable for endoscopic applications. The catheter incorporates a lens actuator that is fabricated using microelectromechanical systems (MEMS) technology. The lens is mounted on a folded flexure made of nickel and is actuated by magnetic field. Thickness measurements are performed by positioning the catheter in front of the tissue and actuating the lens scanner in the out-of-plane direction. A single-mode optical fiber (SMF) is used to deliver a 785 nm laser beam to the tissue and relay back the reflected light from the tissue to a photomultiplier tube (PMT). When the focal point of the scanning lens passes tissue boundaries, intensity peaks are detected in the reflecting signal. Tissue thickness is calculated using its index of refraction and the lens displacement between intensity peaks. The utility of the confocal catheter was demonstrated by measuring the cornea and skin thicknesses of a mouse. Measurement uncertainty of 8.86 µm within 95% confidence interval has been achieved. PMID:21468630

  3. Wearable Biomedical Measurement Systems for Assessment of Mental Stress of Combatants in Real Time

    PubMed Central

    Seoane, Fernando; Mohino-Herranz, Inmaculada; Ferreira, Javier; Alvarez, Lorena; Buendia, Ruben; Ayllón, David; Llerena, Cosme; Gil-Pita, Roberto

    2014-01-01

    The Spanish Ministry of Defense, through its Future Combatant program, has sought to develop technology aids with the aim of extending combatants' operational capabilities. Within this framework the ATREC project funded by the “Coincidente” program aims at analyzing diverse biometrics to assess by real time monitoring the stress levels of combatants. This project combines multidisciplinary disciplines and fields, including wearable instrumentation, textile technology, signal processing, pattern recognition and psychological analysis of the obtained information. In this work the ATREC project is described, including the different execution phases, the wearable biomedical measurement systems, the experimental setup, the biomedical signal analysis and speech processing performed. The preliminary results obtained from the data analysis collected during the first phase of the project are presented, indicating the good classification performance exhibited when using features obtained from electrocardiographic recordings and electrical bioimpedance measurements from the thorax. These results suggest that cardiac and respiration activity offer better biomarkers for assessment of stress than speech, galvanic skin response or skin temperature when recorded with wearable biomedical measurement systems. PMID:24759113

  4. A cavity ring-down spectroscopy sensor for real-time Hall thruster erosion measurements.

    PubMed

    Lee, B C; Huang, W; Tao, L; Yamamoto, N; Gallimore, A D; Yalin, A P

    2014-05-01

    A continuous-wave cavity ring-down spectroscopy sensor for real-time measurements of sputtered boron from Hall thrusters has been developed. The sensor uses a continuous-wave frequency-quadrupled diode laser at 250 nm to probe ground state atomic boron sputtered from the boron nitride insulating channel. Validation results from a controlled setup using an ion beam and target showed good agreement with a simple finite-element model. Application of the sensor for measurements of two Hall thrusters, the H6 and SPT-70, is described. The H6 was tested at power levels ranging from 1.5 to 10 kW. Peak boron densities of 10 ± 2 × 10(14) m(-3) were measured in the thruster plume, and the estimated eroded channel volume agreed within a factor of 2 of profilometry. The SPT-70 was tested at 600 and 660 W, yielding peak boron densities of 7.2 ± 1.1 × 10(14) m(-3), and the estimated erosion rate agreed within ~20% of profilometry. Technical challenges associated with operating a high-finesse cavity in the presence of energetic plasma are also discussed. PMID:24880357

  5. A cavity ring-down spectroscopy sensor for real-time Hall thruster erosion measurements

    SciTech Connect

    Lee, B. C.; Huang, W.; Tao, L.; Yamamoto, N.; Yalin, A. P.; Gallimore, A. D.

    2014-05-15

    A continuous-wave cavity ring-down spectroscopy sensor for real-time measurements of sputtered boron from Hall thrusters has been developed. The sensor uses a continuous-wave frequency-quadrupled diode laser at 250 nm to probe ground state atomic boron sputtered from the boron nitride insulating channel. Validation results from a controlled setup using an ion beam and target showed good agreement with a simple finite-element model. Application of the sensor for measurements of two Hall thrusters, the H6 and SPT-70, is described. The H6 was tested at power levels ranging from 1.5 to 10 kW. Peak boron densities of 10 ± 2 × 10{sup 14} m{sup −3} were measured in the thruster plume, and the estimated eroded channel volume agreed within a factor of 2 of profilometry. The SPT-70 was tested at 600 and 660 W, yielding peak boron densities of 7.2 ± 1.1 × 10{sup 14} m{sup −3}, and the estimated erosion rate agreed within ∼20% of profilometry. Technical challenges associated with operating a high-finesse cavity in the presence of energetic plasma are also discussed.

  6. Direct real-time measurement of shrinkage in photopolymer materials during recording of reflection gratings

    NASA Astrophysics Data System (ADS)

    Vojtíšek, Petr; Květoň, Milan

    2015-05-01

    Photopolymer recording materials aimed at a recording of holograms, diffraction elements for manipulation of light or storing of information received great deal of attention in recent years. For their optimal application it is desirable to characterize them and to know what to expect from them. During the recording of the diffraction gratings (or elements) into this photopolymer materials (but not exclusively) there can be some volume changes of the material itself (so-called shrinkage) which consequently alter the replay performance of such gratings, for example from a perspective of a color fidelity, reconstruction conditions, or diffraction efficiency (in case of a general hologram, the deformation of a holographic image is observed). The main aim is to characterize volume changes and to minimize them with application of some precompensation method in advance and so the resulting grating will have desired properties. In this contribution, we would like to present and discuss measurement method for direct and real-time detection of such volume changes for reflection gratings in low shrinkable photopolymer materials. This measurement method is based on a reconstruction of the grating with low intensity white light under slightly different angle than the angle of the recording is and the analysis on the idea of fringe plane rotation model. For a theoretical background the Kogelnik's Coupled Wave theory and Rigorous Coupled Wave Analysis are used. The recording of the diffraction gratings and measurement of their volume changes is experimentally done for a photopolymer material Bayfol HX101.

  7. Real-time multicamera system for measurement of 3D coordinates by pattern projection

    NASA Astrophysics Data System (ADS)

    Sainov, Ventseslav; Stoykova, Elena; Harizanova, Jana

    2007-06-01

    The report describes a real-time pattern-projection system for measurement of 3D coordinates with simultaneous illumination and recording of four phase-shifted fringe patterns which are projected at four different wavelengths and captured by four synchronized CCD cameras. This technical solution overcomes the main drawback of the temporal phase-shifting profilometry in which the pattern acquisition is made successively in time. The work considers the use of a sinusoidal phase grating as a projection element which is made by analysis of the frequency content of the projected fringes in the Fresnel diffraction zone and by test measurements of relative 3D coordinates that are performed with interferometrically recorded sinusoidal phase gratings on holographic plates. Finally, operation of a four-wavelength profilometric system with four spatially phase-shifted at π/2 sinusoidal phase gratings illuminated with four diode lasers at wavelengths 790 nm, 810 nm, 850 nm and 910 nm is simulated and the systematical error of the profilometric measurement is evaluated.

  8. Real-time Measurements of Biological Particles at Several Continental Sites using the WIBS-4A

    NASA Astrophysics Data System (ADS)

    McMeeking, G. R.; Kok, G. L.; Petters, M. D.; Wright, T.; Hader, J.; Mccubbin, I. B.; Hallar, A. G.; Twohy, C. H.; Toohey, D. W.; DeMott, P. J.; McCluskey, C.; Baumgardner, D.

    2013-12-01

    Biological particles (bacteria, fungi/fungal spores, viruses, algae and fragments of biological material) may play a significant role in modifying cloud properties by acting as ice nuclei and thus have an indirect effect on climate forcing. Little is known, however, regarding the abundance and distribution of biological particles and their importance to cloud microphysics in different environments. On-line, continuous measurement systems offer the potential to measure biological systems at high time resolution and sensitivity, providing greater insight into their distribution in the atmosphere, dispersal mechanisms and potential soures. The WIBS-4A (Wideband Integrated Bioaerosol Sensor) detects fluorescent biological material in real-time associated with individual particles. It measures five properties: a) optical size via light scattering, b) fluorescent emissions in the wavelength range 310-400 following excitation by 280 nm light, c) fluorescent emissions in the wavelength range 420-650 following excitation by 280 nm light, d) fluorescent emissions in the wavelength range 420-650 following excitation by 370 nm light, and e) particle asymmetry factor based on intensities of forward scattered light onto a 4-element detector. Together, these properties aid the classification of sampled particles that contain biofluorophores such as tryptophan or NAD(P)H, which can be found in biological particles. Here we present results from a series of laboratory, ground- and aircraft-based measurements of biological particles using the WIBS-4A. The studies include airborne measurements over the United States, ground-based measurements at a coastal site, an urban site in the southeast US and a high alpine site, and laboratory measurements of a variety of biological and non-biological particles. Our analysis focused on both the characterization of the instrument response as well as an evaluation of its suitability for performing ambient measurements and potential artifacts. We

  9. Real-time Seismic Amplitude Measurement (RSAM): a volcano monitoring and prediction tool

    USGS Publications Warehouse

    Endo, E.T.; Murray, T.

    1991-01-01

    Seismicity is one of the most commonly monitored phenomena used to determine the state of a volcano and for the prediction of volcanic eruptions. Although several real-time earthquake-detection and data acquisition systems exist, few continuously measure seismic amplitude in circumstances where individual events are difficult to recognize or where volcanic tremor is prevalent. Analog seismic records provide a quick visual overview of activity; however, continuous rapid quantitative analysis to define the intensity of seismic activity for the purpose of predicing volcanic eruptions is not always possible because of clipping that results from the limited dynamic range of analog recorders. At the Cascades Volcano Observatory, an inexpensive 8-bit analog-to-digital system controlled by a laptop computer is used to provide 1-min average-amplitude information from eight telemetered seismic stations. The absolute voltage level for each station is digitized, averaged, and appended in near real-time to a data file on a multiuser computer system. Raw realtime seismic amplitude measurement (RSAM) data or transformed RSAM data are then plotted on a common time base with other available volcano-monitoring information such as tilt. Changes in earthquake activity associated with dome-building episodes, weather, and instrumental difficulties are recognized as distinct patterns in the RSAM data set. RSAM data for domebuilding episodes gradually develop into exponential increases that terminate just before the time of magma extrusion. Mount St. Helens crater earthquakes show up as isolated spikes on amplitude plots for crater seismic stations but seldom for more distant stations. Weather-related noise shows up as low-level, long-term disturbances on all seismic stations, regardless of distance from the volcano. Implemented in mid-1985, the RSAM system has proved valuable in providing up-to-date information on seismic activity for three Mount St. Helens eruptive episodes from 1985 to

  10. Enzymatic cycling method using creatine kinase to measure creatine by real-time detection.

    PubMed

    Ueda, Shigeru; Sakasegawa, Shin-Ichi

    2016-08-01

    We have developed a novel enzymatic cycling method that uses creatine kinase (CK) to measure creatine. The method takes advantage of the reversibility of the CK reaction in which the forward (creatine phosphate forming) and reverse reactions are catalyzed in the presence of an excess amount of ATP and IDP, respectively. Real-time detection was accomplished using ADP-dependent glucokinase (ADP-GK) together with glucose-6-phosphate dehydrogenase. ADP, one of the cycling reaction products, was distinguished from IDP by using the nucleotide selectivity of the ADP-GK. The increasing level of ADP was measured from the level of reduced NADP at 340 nm. The method is appropriate for an assay that requires high sensitivity because the rate of increase in absorbance at 340 nm is proportional to the amount of CK present in the reaction mix. We reasoned that the method with CK in combination with creatinine amidohydrolase could be used to assay creatinine, an important marker of kidney function. Our results confirmed the quantitative capability of the assay. PMID:27173608

  11. Real-time holographic interferometry to measure displacement of the facial bone

    NASA Astrophysics Data System (ADS)

    Matsumoto, Toshiro; Tamamura, Kentaro; Tsuchida, Masahisa; Hashimoto, Seiichi; Yabuuchi, Hisashi; Uemura, Kazuyoshi; Sugimura, Masahito

    1998-01-01

    The deformation of the facial bone made up of many complex- formed bones was measured and the role of suture considered with the mechanical response. The displacement of human dried facial bone was measured and considered under static loads by real time holographic interferometry. Materials were dried human skulls. Various loads were applied to the zygomatic, maxillary and the other facial bones by means of a loading apparatus. As the experimental result obtained from the load to the neighborhood of the temporo-zygomatic suture on the temporal bone, density of interference fringes increased on the temporal bone more than on the zygomatic and other facial bones and parallel interference fringes were observed on the temporal bone. The buffer effect on the temporo-zygomatic suture to the load was greater than the sutures of other facial bones. When the amount of load was increased on the same bone, it was expected that the zygomatic arch was broken independently as the type II of the fracture patterns by Knight and NOrth. When the neighborhood of the median suture on the maxillary bone was loaded, fine interference fringes were observed horizontally on the maxillary and zygomatic bones, while coarse interference fringes occurred on the frontal bone and the bilateral fracture pattern by LeFort was expected.

  12. Real-time measurement of sodium chloride in individual aerosol particles by mass spectrometry

    NASA Technical Reports Server (NTRS)

    Sinha, M. P.; Friedlander, S. K.

    1985-01-01

    The method of particle analysis by mass spectrometry has been applied to the quantitative measurement of sodium chloride in individual particles on a real-time basis. Particles of known masses are individually introduced, in the form of a beam, into a miniature Knudsen cell oven (1600 K). The oven is fabricated from rhenium metal sheet (0.018 mm thick) and is situated in the ion source of a quadrupole mass spectrometer. A particle once inside the oven is trapped and completely volatilized; this overcomes the problem of partial volatilization due to particles bouncing from the filament surface. Individual particles are thermally volatilized and ionized inside the rhenium oven, and produce discrete sodium ion pulses whose intensities are measured with the quadrupole mass spectrometer. An ion pulse width of several milliseconds (4-12 ms) is found for particles in the mass range 1.3 x 10 to the -13th to 5.4 x 10 to the -11th g. The sodium ion intensity is found to be proportional to the particle mass to the 0.86-power. The intensity distribution for monodisperse aerosol particles possesses a geometric standard deviation of 1.09, showing that the method can be used for the determination of the mass distribution function with good resolution in a polydisperse aerosol.

  13. Validation of Reference Genes for Accurate Normalization of Gene Expression in Lilium davidii var. unicolor for Real Time Quantitative PCR

    PubMed Central

    Zhang, Jing; Teixeira da Silva, Jaime A.; Wang, ChunXia; Sun, HongMei

    2015-01-01

    Lilium is an important commercial market flower bulb. qRT-PCR is an extremely important technique to track gene expression levels. The requirement of suitable reference genes for normalization has become increasingly significant and exigent. The expression of internal control genes in living organisms varies considerably under different experimental conditions. For economically important Lilium, only a limited number of reference genes applied in qRT-PCR have been reported to date. In this study, the expression stability of 12 candidate genes including α-TUB, β-TUB, ACT, eIF, GAPDH, UBQ, UBC, 18S, 60S, AP4, FP, and RH2, in a diverse set of 29 samples representing different developmental processes, three stress treatments (cold, heat, and salt) and different organs, has been evaluated. For different organs, the combination of ACT, GAPDH, and UBQ is appropriate whereas ACT together with AP4, or ACT along with GAPDH is suitable for normalization of leaves and scales at different developmental stages, respectively. In leaves, scales and roots under stress treatments, FP, ACT and AP4, respectively showed the most stable expression. This study provides a guide for the selection of a reference gene under different experimental conditions, and will benefit future research on more accurate gene expression studies in a wide variety of Lilium genotypes. PMID:26509446

  14. Real-time stroke volume measurements for the optimization of cardiac resynchronization therapy parameters

    PubMed Central

    Dizon, José M.; Quinn, T. Alexander; Cabreriza, Santos E.; Wang, Daniel; Spotnitz, Henry M.; Hickey, Kathleen; Garan, Hasan

    2010-01-01

    Aims We investigated the utility of real-time stroke volume (SV) monitoring via the arterial pulse power technique to optimize cardiac resynchronization therapy (CRT) parameters at implant and prospectively evaluated the clinical and echocardiographic results. Methods and results Fifteen patients with ischaemic or non-ischaemic dilated cardiomyopathy, sinus rhythm, Class III congestive heart failure, and QRS >150 ms underwent baseline 2D echocardiogram (echo), 6 min walk distance, and quality of life (QOL) questionnaire  within 1 week of implant. Following implant, 0.3 mmol lithium chloride was injected to calibrate SV via dilution curve. Atrioventricular (AV) delay (90, 120, 200 ms, baseline: atrial pacing only) and V-V delay (−80 to 80 ms in 20 ms increments) were varied every 60 s. The radial artery pulse power autocorrelation method (PulseCO algorithm, LiDCO, Ltd.) was used to monitor SV on a beat-to-beat basis (LiDCO, Ltd.). Optimal parameters were programmed and echo, 6 min walk, and QOL were repeated at 6–8 weeks post-implant. Nine patients had >5% increase in SV after optimization (Group A). Six patients had <5% improvement in SV (Group B). Compared with Group B, Group A had significant improvements in left ventricular ejection fraction (LVEF) (11.0 ± 8.5 vs. 0.8 ± 2.0%) and decrease in left ventricular end-diastolic dimension (LVEDD) (−0.6 ± 0.4 vs. −0.2 ± 0.2 cm) and 6 min walk (346 ± 226 vs. 32 ±271 ft, P ≤ 0.05). Group A patients also tended to have greater improvement in the septal-to-posterior wall motion delay on M-mode echo (P = 0.07). Conclusion Real-time SV measurements can be used to optimize CRT at the time of implant. Improvement in SV correlates with improvement in LVEF, LVEDD, and 6 min walk, and improvement in echocardiographic dyssynchrony. PMID:20525728

  15. Environmental Measurement While Drilling System for Real-Time Field Screening of Contaminants

    SciTech Connect

    Lockwood, G.J.; Normann, R.A.; Williams, C.V.

    1999-02-22

    Sampling during environmental drilling is essential to fully characterize the spatial distribution and migration of subsurface contaminants. However, analysis of the samples is expensive and time-consuming: off-site laboratory analysis can take weeks or months. Real-time information on environmental conditions, drill bit location and temperature during drilling is valuable in many environmental restoration operations. This type of information can be used to provide field screening data and improved efficiency of site characterization activities. The Environmental Measurement-While-Drilling (EMWD) System represents an innovative blending of new and existing technology in order to obtain real-time data during drilling. The system consists of two subsystems. The down-hole subsystem (at the drill bit) consists of sensors, a power supply, a signal conditioning and transmitter board, and a radio-frequency (RF) coaxial cable. The up-hole subsystem consists of a battery pack/coil, pickup coil, receiver, and personal computer. The system is compatible with fluid miser drill pipe, a directional drilling technique that uses minimal drilling fluids and generates little to no secondary waste. In EMWD, downhole sensors are located behind the drill bit and linked by a high-speed data transmission system to a computer at the surface. Sandia-developed Windows{trademark}-based software is used for data display and storage. As drilling is conducted, data is collected on the nature and extent of contamination, enabling on-the-spot decisions regarding drilling and sampling strategies. Initially, the downhole sensor consisted of a simple gamma radiation detector, a Geiger-Mueller tube (GMT). The design includes data assurance techniques to increase safety by reducing the probability of giving a safe indication when an unsafe condition exists. The EMWD system has been improved by the integration of a Gamma Ray Spectrometer (GRS) in place of the GMT. The GRS consists of a sodium iodide

  16. DEVELOPMENT OF AN ON-LINE, REAL-TIME ALPHA RADIATION MEASURING INSTRUMENT FOR LIQUID STREAMS

    SciTech Connect

    Unknown

    1999-03-14

    The US Department of Energy (DOE) has expressed a need for an on-line, real-time instrument for assaying alpha-emitting radionuclides (uranium and the transuranics) in effluent waters leaving DOE sites to ensure compliance with regulatory limits. Due to the short range of alpha particles in water ({approximately}40 Im), it is necessary now to intermittently collect samples of water and send them to a central laboratory for analysis. A lengthy and costly procedure is used to separate and measure the radionuclides from each sample. Large variations in radionuclide concentrations in the water may go undetected due to the sporadic sampling. Even when detected, the reading may not be representative of the actual stream concentration. To address these issues, the Advanced Technologies Group of Thermo Power Corporation (a Thermo Electron company) is developing a real-time, field-deployable alpha monitor based on a solid-state silicon wafer semiconductor (US Patent 5,652,013 and pending, assigned to the US Department of Energy). The Thermo Water Alpha Monitor will serve to monitor effluent water streams (Subsurface Contaminants Focus Area) and will be suitable for process control of remediation as well as decontamination and decommissioning (D and D) operations, such as monitoring scrubber or rinse water radioactivity levels (Mixed Waste, Plutonium, and D and D Focus Area). It would be applicable for assaying other liquids, such as oil, or solids after proper preconditioning. Rapid isotopic alpha air monitoring is also possible using this technology. This report details the program's accomplishments to date. Most significantly, the Alpha Monitoring Instrument was successfully field demonstrated on water 100X below the Environmental Protection Agency's proposed safe drinking water limit--down to under 1 pCi/1. During the Field Test, the Alpha Monitoring Instrument successfully analyzed isotopic uranium levels on a total of five different surface water, process water, and

  17. DEVELOPMENT OF AN ON-LINE, REAL-TIME ALPHA RADIATION MEASURING INSTRUMENT FOR LIQUID STREAMS

    SciTech Connect

    1996-11-22

    The Department of Energy (DOE) has expressed a need for an on-line, real-time instrument for assaying alpha-emitting radionuclides (uranium and the transuranics) in effluent waters leaving DOE sites to ensure compliance with regulatory limits. Due to the short range of alpha particles in water ({approximately}40 Tm), it is necessary now to intermittently collect samples of water and send them to a central laboratory for analysis. A lengthy and costly procedure is used to separate and measure the radionuclides from each sample. Large variations in radionuclide concentrations in the water may go undetected due to the sporadic sampling. Even when detected, the reading may not be representative of the actual stream concentration. To address these issues, Tecogen, a division of Thermo Power Corporation, a Thermo Electron company, is developing a real-time, field-deployable, alpha monitor based on a solid-state silicon wafer semiconductor (patent pending, to be assigned to the Department of Energy). The Thermo Alpha Monitor (TAM) will serve to monitor effluent water streams (Subsurface Contaminants Focus Area) and will be suitable for process control of remediation as well as decontamination and decommissioning operations, such as monitoring scrubber or rinse water radioactivity levels (Mixed Waste Focus Area and D&D Focus Area). It would be applicable for assaying other liquids, such as oil, or solids after proper preconditioning. Rapid isotopic alpha air monitoring is also possible using this technology. This instrument for direct counting of alpha-emitters in aqueous streams is presently being developed by Thermo Power under a development program funded by the DOE Environmental Management program (DOE-EM), administered by the Morgantown Energy Technology Center (METC). Under this contract, Thermo Power has demonstrated a solid-state, silicon-based semiconductor instrument, which uses a proprietary film-based collection system to quantitatively extract the

  18. Engineering genetically encoded nanosensors for real-time in vivo measurements of citrate concentrations.

    PubMed

    Ewald, Jennifer C; Reich, Sabrina; Baumann, Stephan; Frommer, Wolf B; Zamboni, Nicola

    2011-01-01

    Citrate is an intermediate in catabolic as well as biosynthetic pathways and is an important regulatory molecule in the control of glycolysis and lipid metabolism. Mass spectrometric and NMR based metabolomics allow measuring citrate concentrations, but only with limited spatial and temporal resolution. Methods are so far lacking to monitor citrate levels in real-time in-vivo. Here, we present a series of genetically encoded citrate sensors based on Förster resonance energy transfer (FRET). We screened databases for citrate-binding proteins and tested three candidates in vitro. The citrate binding domain of the Klebsiella pneumoniae histidine sensor kinase CitA, inserted between the FRET pair Venus/CFP, yielded a sensor highly specific for citrate. We optimized the peptide linkers to achieve maximal FRET change upon citrate binding. By modifying residues in the citrate binding pocket, we were able to construct seven sensors with different affinities spanning a concentration range of three orders of magnitude without losing specificity. In a first in vivo application we show that E. coli maintains the capacity to take up glucose or acetate within seconds even after long-term starvation. PMID:22164251

  19. Real-time analysis system for gas turbine ground test acoustic measurements.

    PubMed

    Johnston, Robert T

    2003-10-01

    This paper provides an overview of a data system upgrade to the Pratt and Whitney facility designed for making acoustic measurements on aircraft gas turbine engines. A data system upgrade was undertaken because the return-on-investment was determined to be extremely high. That is, the savings on the first test series recovered the cost of the hardware. The commercial system selected for this application utilizes 48 input channels, which allows either 1/3 octave and/or narrow-band analyses to be preformed real-time. A high-speed disk drive allows raw data from all 48 channels to be stored simultaneously while the analyses are being preformed. Results of tests to ensure compliance of the new system with regulations and with existing systems are presented. Test times were reduced from 5 h to 1 h of engine run time per engine configuration by the introduction of this new system. Conservative cost reduction estimates for future acoustic testing are 75% on items related to engine run time and 50% on items related to the overall length of the test. PMID:14582877

  20. Real-time intermembrane force measurements and imaging of lipid domain morphology during hemifusion

    PubMed Central

    Lee, Dong Woog; Kristiansen, Kai; Donaldson, Jr., Stephen H.; Cadirov, Nicholas; Banquy, Xavier; Israelachvili, Jacob N.

    2015-01-01

    Membrane fusion is the core process in membrane trafficking and is essential for cellular transport of proteins and other biomacromolecules. During protein-mediated membrane fusion, membrane proteins are often excluded from the membrane–membrane contact, indicating that local structural transformations in lipid domains play a major role. However, the rearrangements of lipid domains during fusion have not been thoroughly examined. Here using a newly developed Fluorescence Surface Forces Apparatus (FL-SFA), migration of liquid-disordered clusters and depletion of liquid-ordered domains at the membrane–membrane contact are imaged in real time during hemifusion of model lipid membranes, together with simultaneous force–distance and lipid membrane thickness measurements. The load and contact time-dependent hemifusion results show that the domain rearrangements decrease the energy barrier to fusion, illustrating the significance of dynamic domain transformations in membrane fusion processes. Importantly, the FL-SFA can unambiguously correlate interaction forces and in situ imaging in many dynamic interfacial systems. PMID:26006266

  1. Model-based assessment of erlotinib effect in vitro measured by real-time cell analysis.

    PubMed

    Benay, Stephan; Meille, Christophe; Kustermann, Stefan; Walter, Isabelle; Walz, Antje; Gonsard, P Alexis; Pietilae, Elina; Kratochwil, Nicole; Iliadis, Athanassios; Roth, Adrian; Lave, Thierry

    2015-06-01

    Real time cell analysis (RTCA) is an impedance-based technology which tracks various living cell characteristics over time, such as their number, morphology or adhesion to the extra cellular matrix. However, there is no consensus about how RTCA data should be used to quantitatively evaluate pharmacodynamic parameters which describe drug efficacy or toxicity. The purpose of this work was to determine how RTCA data can be analyzed with mathematical modeling to explore and quantify drug effect in vitro. The pharmacokinetic-pharmacodynamic erlotinib concentration profile predicted by the model and its effect on the human epidermoïd carcinoma cell line A431 in vitro was measured through RTCA output, designated as cell index. A population approach was used to estimate model parameter values, considering a plate well as the statistical unit. The model related the cell index to the number of cells by means of a proportionality factor. Cell growth was described by an exponential model. A delay between erlotinib pharmacokinetics and cell killing was described by a transit compartment model, and the effect potency, by an E max function of erlotinib concentration. The modeling analysis performed on RTCA data distinguished drug effects in vitro on cell number from other effects likely to modify the relationship between cell index and cell number. It also revealed a time-dependent decrease of erlotinib concentration over time, described by a mono-exponential pharmacokinetic model with nonspecific binding. PMID:25822652

  2. KERMA-based radiation dose management system for real-time patient dose measurement

    NASA Astrophysics Data System (ADS)

    Kim, Kyo-Tae; Heo, Ye-Ji; Oh, Kyung-Min; Nam, Sang-Hee; Kang, Sang-Sik; Park, Ji-Koon; Song, Yong-Keun; Park, Sung-Kwang

    2016-07-01

    Because systems that reduce radiation exposure during diagnostic procedures must be developed, significant time and financial resources have been invested in constructing radiation dose management systems. In the present study, the characteristics of an existing ionization-based system were compared to those of a system based on the kinetic energy released per unit mass (KERMA). Furthermore, the feasibility of using the KERMA-based system for patient radiation dose management was verified. The ionization-based system corrected the effects resulting from radiation parameter perturbations in general radiography whereas the KERMA-based system did not. Because of this difference, the KERMA-based radiation dose management system might overestimate the patient's radiation dose due to changes in the radiation conditions. Therefore, if a correction factor describing the correlation between the systems is applied to resolve this issue, then a radiation dose management system can be developed that will enable real-time measurement of the patient's radiation exposure and acquisition of diagnostic images.

  3. Real-time intermembrane force measurements and imaging of lipid domain morphology during hemifusion

    NASA Astrophysics Data System (ADS)

    Lee, Dong Woog; Kristiansen, Kai; Donaldson, Stephen H., Jr.; Cadirov, Nicholas; Banquy, Xavier; Israelachvili, Jacob N.

    2015-05-01

    Membrane fusion is the core process in membrane trafficking and is essential for cellular transport of proteins and other biomacromolecules. During protein-mediated membrane fusion, membrane proteins are often excluded from the membrane-membrane contact, indicating that local structural transformations in lipid domains play a major role. However, the rearrangements of lipid domains during fusion have not been thoroughly examined. Here using a newly developed Fluorescence Surface Forces Apparatus (FL-SFA), migration of liquid-disordered clusters and depletion of liquid-ordered domains at the membrane-membrane contact are imaged in real time during hemifusion of model lipid membranes, together with simultaneous force-distance and lipid membrane thickness measurements. The load and contact time-dependent hemifusion results show that the domain rearrangements decrease the energy barrier to fusion, illustrating the significance of dynamic domain transformations in membrane fusion processes. Importantly, the FL-SFA can unambiguously correlate interaction forces and in situ imaging in many dynamic interfacial systems.

  4. Real-Time Measurement of Volatile Chemicals Released by Bed Bugs during Mating Activities

    PubMed Central

    Kilpinen, Ole; Liu, Dezhao; Adamsen, Anders Peter S.

    2012-01-01

    In recent years, bed bug (Hemiptera: Cimicidae) problems have increased dramatically in many parts of the world, leading to a renewed interest in their chemical ecology. Most studies of bed bug semiochemicals have been based on the collection of volatiles over a period of time followed by chemical analysis. Here we present for the first time, a combination of proton transfer reaction mass spectrometry and video analysis for real-time measurement of semiochemicals emitted by isolated groups of bed bugs during specific behavioural activities. The most distinct peaks in the proton transfer reaction mass spectrometry recordings were always observed close to the termination of mating attempts, corresponding to the defensive emissions that bed bugs have been suspected to exploit for prevention of unwanted copulations. The main components of these emissions were (E)-2-hexenal and (E)-2-octenal recorded in ratios between 1∶3 and 3∶1. In the current study, the quantity varied over 1000 fold for both of the compounds with up to 40 µg total release in a single emission. Males also emit defensive compounds due to homosexual copulation attempts by other males, and no significant differences were observed in the ratio or the amount of the two components released from males or females. In summary, this study has demonstrated that combining proton-transfer-reaction mass spectrometry with video analysis can provide detailed information about semiochemicals emitted during specific behavioural activities. PMID:23227225

  5. Measurement of displacement on facial bone by real-time holographic interferometry

    NASA Astrophysics Data System (ADS)

    Matsumoto, Toshiro; Taga, Masao; Tsuchida, Masahisa; Yoshioka, Minoru; Uemura, Kazuyoshi; Sugimura, Masahito

    1996-01-01

    The displacement of human dried facial bone was measured and considered under static loads by real time holographic interferometry. Materials were dried human skulls. Various loads were applied to the zygomatic, maxillary and other facial bones by means of a loading apparatus. As the experimental result obtained from the load to the neighborhood of the fronto-malar suture on the zygomatic bone, density of interference fringes increased on the zygomatic bone more than on the other facial bones and parallel interference fringes were observed on the zygomatic bone. Densities of orbital maxillary and zygomatic bones were greater, when the load was applied to the center of infraorbital margin than when it was applied to the other facial bones. When the neighborhood of the front-malar suture on the frontal bone was loaded, coarse interference fringes occurred on the zygomatic, maxillary and orbital bones, while fine interference fringes appeared on the frontal bone. When the maxillary bone near infraorbital margin was loaded, concentric circular fringes were observed. The result shows that the displacement depends on the loading point. When the load applied to the zygomatic bone, parallel fringes appeared on the bone. This means that the bone deformed almost as a body.

  6. Real-time measurement of the emergence of superconducting order in a high-temperature superconductor

    NASA Astrophysics Data System (ADS)

    Madan, I.; Kusar, P.; Baranov, V. V.; Lu-Dac, M.; Kabanov, V. V.; Mertelj, T.; Mihailovic, D.

    2016-06-01

    Systems which rapidly evolve through symmetry-breaking transitions on timescales comparable to the fluctuation timescale of the single-particle excitations may behave very differently than under controlled near-ergodic conditions. A real-time investigation with high temporal resolution may reveal insights into the ordering through the transition that are not available in static experiments. We present an investigation of the system trajectory through a normal-to-superconductor transition in a prototype high-temperature superconducting cuprate in which such a situation occurs. Using a multiple pulse femtosecond spectroscopy technique we measure the system trajectory and time evolution of the single-particle excitations through the transition in La1.9Sr0.1CuO4 and compare the data to a simulation based on the time-dependent Ginzburg-Landau theory, using the laser excitation fluence as an adjustable parameter controlling the quench conditions in both experiment and theory. The comparison reveals the presence of significant superconducting fluctuations which precede the transition on short timescales. By including superconducting fluctuations as a seed for the growth of the superconducting order we can obtain a satisfactory agreement of the theory with the experiment. Remarkably, the pseudogap excitations apparently play no role in this process.

  7. Kinetics and thermodynamics of sucrose hydrolysis from real-time enthalpy and heat capacity measurements.

    PubMed

    Tombari, E; Salvetti, G; Ferrari, C; Johari, G P

    2007-01-25

    We report a real time study of the enthalpy release and heat capacity during the course of HCl-catalyzed hydrolysis of sucrose to fructose and glucose. Measurements were performed during both isothermal conditions and during slow heating and then cooling at a controlled rate. The reaction rate constant of the first-order kinetics follows an Arrhenius relation with activation energy of 109.2 kJ/mol of sucrose. On hydrolysis, the enthalpy decreases by 14.4 kJ/mol of sucrose at 310 K, and the heat capacity, Cp, increases by 61 J mol-1 K-1 of sucrose in the solution. The enthalpy of hydrolysis decreases with increase in the temperature and DeltaCp on hydrolysis increases. The effects are attributed to change in the configurational and vibrational partition functions as one covalent bond in sucrose breaks to form two molecules, which then individually form additional hydrogen bonds and alter the water's structure in the solution. Cp of the solution increases with temperature less rapidly before sucrose hydrolysis than after it. This may reflect an increase in the configurational contribution to Cp as the hydrogen bond population changes. PMID:17228904

  8. Real-time measurement of glucose using chrono-impedance technique on a second generation biosensor.

    PubMed

    Mayorga Martinez, Carmen C; Treo, Ernesto F; Madrid, Rossana E; Felice, Carmelo C

    2011-11-15

    Chrono-impedance technique (CIT) was implemented as a new transduction method for real time measurement of glucose in a biosensor system based in carbon paste (CP)/Ferrocene (FC)/glucose oxidase (GOx). The system presents high selectivity because the optimal stimulation signal composed by a 165mV DC potential and 50mV(RMS) AC signal at 0.4Hz was used. The low DC potential used decreased the interfering species effect and the biosensor showed a linear impedance response toward glucose detection at concentrations from 0mM to 20mM,with 0.9853 and 0.9945 correlation coefficient for impedance module (|Z|) and phase (Φ), respectively. The results of quadruplicate sets reveal the high repeatability and reproducibility of the measurements with a relative standard deviation (RSD) less than 10%. CIT presented good accuracy (within 10% of the actual value) and precision did not exceed 15% of RSD for high concentration values and 20% for the low concentration ones. In addition, a high correlation coefficient (R(2)=0.9954) between chrono-impedance and colorimetric methods was obtained. On the other hand, when two samples prepared at the same conditions were measured in parallel with both methods (the measurement was repeated four times), it should be noticed that student's t-test produced no difference between the two mentioned methods (p=1). The biosensor system hereby presented is highly specific to glucose detection and shows a better linear range than the one reported on the previous article. PMID:21907557

  9. In vitro Real-time Measurement of the Intra-bacterial Redox Potential

    PubMed Central

    van der Heijden, Joris; Finlay, B. Brett

    2016-01-01

    All bacteria that live in oxygenated environments have to deal with oxidative stress caused by some form of exogenous or endogenous reactive oxygen species (ROS) (Imlay, 2013). Large quantities of ROS damage DNA, lipids and proteins which can eventually lead to bacterial cell death (Imlay, 2013). In contrast, smaller quantities of ROS can play more sophisticated roles in cellular signalling pathways affecting almost every process in the bacterial cell e.g. metabolism, stress responses, transcription, protein synthesis, etc. Previously, inadequate analytical methods prevented appropriate analysis of the intra-bacterial redox potential. Herein, we describe a method for the measurement of real-time changes to the intra-bacterial redox potential using redox-sensitive GFP (roGFP2) (van der Heijden et al., 2015). The roGFP2 protein is engineered to contain specific cysteine residues that form an internal disulfide bridge upon oxidation which results in a slight shift in protein conformation (Hanson et al., 2004). This shift results in two distinct protein isoforms with different fluorescence excitation spectra after excitation at 405 nm and 480 nm respectively. Consequently, the corresponding 405/480 nm ratio can be used as a measure for the intra-bacterial redox potential. The ratio-metric analysis excludes variations due to differences in roGFP2 concentrations and since the conformational shift is reversible the system allows for measurement of oxidizing as well as reducing conditions. In this protocol we describe the system by measuring the intra-bacterial redox potential inside Salmonella typhimurium (S. typhimurium) however this system can be adjusted for use in other Gram-negative bacteria.

  10. Measuring real-time streamflow using emerging technologies: Radar, hydroacoustics, and the probability concept

    USGS Publications Warehouse

    Fulton, J.; Ostrowski, J.

    2008-01-01

    Forecasting streamflow during extreme hydrologic events such as floods can be problematic. This is particularly true when flow is unsteady, and river forecasts rely on models that require uniform-flow rating curves to route water from one forecast point to another. As a result, alternative methods for measuring streamflow are needed to properly route flood waves and account for inertial and pressure forces in natural channels dominated by nonuniform-flow conditions such as mild water surface slopes, backwater, tributary inflows, and reservoir operations. The objective of the demonstration was to use emerging technologies to measure instantaneous streamflow in open channels at two existing US Geological Survey streamflow-gaging stations in Pennsylvania. Surface-water and instream-point velocities were measured using hand-held radar and hydroacoustics. Streamflow was computed using the probability concept, which requires velocity data from a single vertical containing the maximum instream velocity. The percent difference in streamflow at the Susquehanna River at Bloomsburg, PA ranged from 0% to 8% with an average difference of 4% and standard deviation of 8.81 m3/s. The percent difference in streamflow at Chartiers Creek at Carnegie, PA ranged from 0% to 11% with an average difference of 5% and standard deviation of 0.28 m3/s. New generation equipment is being tested and developed to advance the use of radar-derived surface-water velocity and instantaneous streamflow to facilitate the collection and transmission of real-time streamflow that can be used to parameterize hydraulic routing models.

  11. Real-time measurements to characterize dynamics of emulsion interface during simulated intestinal digestion.

    PubMed

    Pan, Yuanjie; Nitin, N

    2016-05-01

    Efficient delivery of bioactives remains a critical challenge due to their limited bioavailability and solubility. While many encapsulation systems are designed to modulate the digestion and release of bioactives within the human gastrointestinal tract, there is limited understanding of how engineered structures influence the delivery of bioactives. The objective of this study was to develop a real-time quantitative method to measure structural changes in emulsion interface during simulated intestinal digestion and to correlate these changes with the release of free fatty acids (FFAs). Fluorescence resonant energy transfer (FRET) was used for rapid in-situ measurement of the structural changes in emulsion interface during simulated intestinal digestion. By using FRET, changes in the intermolecular spacing between the two different fluorescent probes labeled emulsifier were characterized. Changes in FRET measurements were compared with the release of FFAs. The results showed that bile salts and pancreatic lipase interacted immediately with the emulsion droplets and disrupted the emulsion interface as evidenced by reduction in FRET efficacy compared to the control. Similarly, a significant amount of FFAs was released during digestion. Moreover, addition of a second layer of polymers at emulsion interface decreased the extent of interface disruption by bile salts and pancreatic lipase and impacted the amount or rate of FFA release during digestion. These results were consistent with the lower donor/acceptor ratio of the labeled probes from the FRET result. Overall, this study provides a novel approach to analyze the dynamics of emulsion interface during digestion and their relationship with the release of FFAs. PMID:26854582

  12. First measurement of pp neutrinos in real time in the Borexino detector

    NASA Astrophysics Data System (ADS)

    Mosteiro, Pablo

    2014-09-01

    The Sun is fueled by a series of nuclear reactions that produce the energy that makes it shine. Neutrinos (nu) produced by these nuclear reactions exit the Sun and reach Earth within minutes, providing us with key information about what goes on at the core of our star. For over twenty years since the first detection of solar neutrinos in the late 1960's, an apparent deficit in their detection rate was known as the Solar Neutrino Problem. Today, the Mikheyev-Smirnov-Wolfenstein (MSW) effect is the accepted mechanism by which neutrinos oscillate inside the Sun, arriving at Earth as a mixture of nue, numu and nutau, the latter two of which were invisible to early detectors. Several experiments have now confirmed the observation of neutrino oscillations. These experiments, when their results are combined together, have demonstrated that neutrino oscillations are well described by the Large Mixing Angle (LMA) solution of the MSW effect. This thesis presents the first measurement of pp neutrinos in the Borexino detector, which is another validation of the LMA-MSW model of neutrino oscillations. In addition, it is one more step towards the completion of the spectroscopy of pp chain neutrinos in Borexino, leaving only the extremely faint hep neutrinos undetected. This advance validates the experiment itself and its previous results. This is, furthermore, the first direct real-time measurement of pp neutrinos. We find a pp neutrino detection rate of 143+/-16 (stat)+/-10 (syst) cpd/100 t in the Borexino experiment, which translates, according to the LMA-MSW model, to (6.42+/-0.85)x1010 cm -2 s-1. We also report on a measurement of neutrons in a dedicated system within the Borexino detector, which resulted in an improved understanding of neutron rates in liquid scintillator detectors at Gran Sasso depths. This result is crucial to the development of novel direct dark matter detection experiments.

  13. A bio-inspired real-time capable artificial lateral line system for freestream flow measurements.

    PubMed

    Abels, C; Qualtieri, A; De Vittorio, M; Megill, W M; Rizzi, F

    2016-06-01

    To enhance today's artificial flow sensing capabilities in aerial and underwater robotics, future robots could be equipped with a large number of miniaturized sensors distributed over the surface to provide high resolution measurement of the surrounding fluid flow. In this work we show a linear array of closely separated bio-inspired micro-electro-mechanical flow sensors whose sensing mechanism is based on a piezoresistive strain-gauge along a stress-driven cantilever beam, mimicking the biological superficial neuromasts found in the lateral line organ of fishes. Aiming to improve state-of-the-art flow sensing capability in autonomously flying and swimming robots, our artificial lateral line system was designed and developed to feature multi-parameter freestream flow measurements which provide information about (1) local flow velocities as measured by the signal amplitudes from the individual cantilevers as well as (2) propagation velocity, (3) linear forward/backward direction along the cantilever beam orientation and (4) periodicity of pulses or pulse trains determined by cross-correlating sensor signals. A real-time capable cross-correlation procedure was developed which makes it possible to extract freestream flow direction and velocity information from flow fluctuations. The computed flow velocities deviate from a commercial system by 0.09 m s(-1) at 0.5 m s(-1) and 0.15 m s(-1) at 1.0 m s(-1) flow velocity for a sampling rate of 240 Hz and a sensor distance of 38 mm. Although experiments were performed in air, the presented flow sensing system can be applied to underwater vehicles as well, once the sensors are embedded in a waterproof micro-electro-mechanical systems package. PMID:27257144

  14. Wavelength-dependent backscattering measurements for quantitative real-time monitoring of apoptosis in living cells

    NASA Astrophysics Data System (ADS)

    Mulvey, Christine S.; Sherwood, Carly A.; Bigio, Irving J.

    2009-11-01

    Apoptosis-programmed cell death-is a cellular process exhibiting distinct biochemical and morphological changes. An understanding of the early morphological changes that a cell undergoes during apoptosis can provide the opportunity to monitor apoptosis in tissue, yielding diagnostic and prognostic information. There is avid interest regarding the involvement of apoptosis in cancer. The initial response of a tumor to successful cancer treatment is often massive apoptosis. Current apoptosis detection methods require cell culture disruption. Our aim is to develop a nondisruptive optical method to monitor apoptosis in living cells and tissues. This would allow for real-time evaluation of apoptotic progression of the same cell culture over time without alteration. Elastic scattering spectroscopy (ESS) is used to monitor changes in light-scattering properties of cells in vitro due to apoptotic morphology changes. We develop a simple instrument capable of wavelength-resolved ESS measurements from cell cultures in the backward direction. Using Mie theory, we also develop an algorithm that extracts the size distribution of scatterers in the sample. The instrument and algorithm are validated with microsphere suspensions. For cell studies, Chinese hamster ovary (CHO) cells are cultured to confluence on plates and are rendered apoptotic with staurosporine. Backscattering measurements are performed on pairs of treated and control samples at a sequence of times up to 6-h post-treatment. Initial results indicate that ESS is capable of discriminating between treated and control samples as early as 10- to 15-min post-treatment, much earlier than is sensed by standard assays for apoptosis. Extracted size distributions from treated and control samples show a decrease in Rayleigh and 150-nm scatterers, relative to control samples, with a corresponding increase in 200-nm particles. Work continues to correlate these size distributions with underlying morphology. To our knowledge, this

  15. Research progress on real-time measurement of soil attributes for precision agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rapid and accurate measurement of soil organic matter content and nitrogen, phosphorus, potassium and other nutrients is the basis for variable rate fertilizer application in precision agriculture, and it is also a difficult problem that scientists have been committed to resolving. On the basis of ...

  16. CLEAR PM: Teaching, Outreach, and Research Through Real-Time Particulate Measurements

    NASA Astrophysics Data System (ADS)

    DeCarlo, P. F.

    2013-12-01

    An understanding of particulate matter (also called aerosols) can be made through measurement. This measurement does not change in value if it is made in a teaching, research, or outreach environment. A grant from the Camille and Henry Dreyfus Foundation provided funding to construct an instrument suite composed of 1-4 second measurements that are displayed in real-time through a software interface. This display module is called CLEAR PM (Chemistry Lessons Enabling Aerosol Realizations through Particulate Measurement), and was conceived to apply across outreach activities, teaching activities, and research activities. The construction and software design of CLEAR PM was done as part of a special topics course for chemistry and engineering graduate students at Drexel University. Measurement principles of the different (research grade) instruments were taught as part of the course, with emphasis put on the fundamental measurements and their limitations, and an introduction to data acquisition software was also integral to the teaching component. As a final project of the course graduate students were required to create a 'teaching' module that illustrates a chemistry or physics concept and utilizes the measurements of CLEAR PM. These modules ranged from gas-phase ozone chemistry creating secondary organic aerosols, to the wavelength dependent absorption profiles of wood smoke versus propane soot. The teaching modules developed by the graduate students have been used in outreach activities sponsored by The Franklin Institute and the Clean Air Council in Philadelphia, where underrepresented groups often make up a large fraction of the audience. CLEAR PM is designed to give students and citizens a hands-on opportunity to see how we measure and understand the world around us. As mentioned previously, the instruments that are part of CLEAR PM are research grade instruments, and are actively being used in research projects in the DeCarlo lab at Drexel to study particulate

  17. Real-time indoor and outdoor measurements of black carbon at primary schools

    NASA Astrophysics Data System (ADS)

    Reche, C.; Rivas, I.; Pandolfi, M.; Viana, M.; Bouso, L.; Àlvarez-Pedrerol, M.; Alastuey, A.; Sunyer, J.; Querol, X.

    2015-11-01

    Epidemiological and toxicological studies have demonstrated the association between Black Carbon in indoor and outdoor air and the occurrence of health risks. Data on air quality in schools is of special interest, as children are more vulnerable to health hazards. In this context, indoor and outdoor measurements of real-time Equivalent Black Carbon (EBC) were collected at 39 primary schools located in Barcelona (Spain), with classrooms naturally ventilated under warm weather conditions. A main contribution of road traffic emissions to indoor and outdoor EBC levels was evidenced through different approaches. Simultaneous measurements of EBC levels at schools under different traffic conditions revealed concentrations by 30-35% higher at schools exposed to higher vehicles intensities. Moreover, a significant correlation was obtained between average outdoor EBC levels at different districts of the city and the percentage of surface area in each district used for the road network (R2 = 0.61). Higher indoor than outdoor levels were recorded at some instances when the indoor sampling location was relatively closer to road traffic, even under low outdoor temperatures. Indeed, the average indoor/outdoor EBC ratios for each school correlate moderately between campaigns in spite of significant differences in temperature between sampling periods. These two facts highlight the strong dependency of the EBC levels on the distance to traffic. The peaks of exposure inside the classrooms seemed to be determined by outdoor concentrations, as shown by the parallelism between indoor and outdoor mean EBC daily cycles and the similar contribution of traffic rush hours to indoor and outdoor daily mean levels. The airtightness of the classroom was suggested as the responsible for the indoor/outdoor ratios of EBC higher than 1 recorded at nights.

  18. Real-Time Quadrature Measurement of a Single-Photon Wave Packet with Continuous Temporal-Mode Matching

    NASA Astrophysics Data System (ADS)

    Ogawa, Hisashi; Ohdan, Hideaki; Miyata, Kazunori; Taguchi, Masahiro; Makino, Kenzo; Yonezawa, Hidehiro; Yoshikawa, Jun-ichi; Furusawa, Akira

    2016-06-01

    Real-time controls based on quantum measurements are powerful tools for various quantum protocols. However, their experimental realization has been limited by mode mismatch between the temporal mode of quadrature measurement and that heralded by photon detection. Here, we demonstrate real-time quadrature measurement of a single-photon wave packet induced by photon detection by utilizing continuous temporal-mode matching between homodyne detection and an exponentially rising temporal mode. Single photons in exponentially rising modes are also expected to be useful resources for interactions with other quantum systems.

  19. Real time black carbon measurements in West and Central Africa urban sites

    NASA Astrophysics Data System (ADS)

    Doumbia, El Hadji Thierno; Liousse, Catherine; Galy-Lacaux, Corinne; Ndiaye, Seydi Ababacar; Diop, Babacar; Ouafo, Marie; Assamoi, Eric Michel; Gardrat, Eric; Castera, Pierre; Rosset, Robert; Akpo, Aristide; Sigha, Luc

    2012-07-01

    Real time measurements of Black Carbon (BC) in PM2.5 aerosols were performed during AMMA and POLCA programs, between 2005 and 2010 in Cotonou (Benin), Dakar (Senegal), Bamako (Mali), and Yaounde (Cameroon). Indeed, BC was chosen as a metric because of its interest as an urban pollutant. The instrumented sites are representative of the traffic source. At Dakar, BC concentrations are high from November to April (13,000 ± 3500 ng m-3) and lower from May to September (8000 ± 3200 ng m-3). In dry season (November-April), high BC concentrations occurred as a result of northeasterly long-range transport of polluted air masses over West Africa, in addition to local emissions. However, during wet season (May-September) reduced traffic levels, school vacations and wet deposition processes contribute to lower BC concentration levels. Measured diurnal BC peak concentrations, at all sites, mainly occur during morning and evening rush-hour periods, indicating the paramount role of traffic. Highest values are observed between 5-9 a.m. and from 5 p.m. to 9 p.m. depending on the site, while lowest are occurred at night time and middle afternoon when activities of the population are reduced. BC source apportionment from absorption measurements also confirmed the relative importance of traffic (88%) versus biomass burning (12%). Also, BC measurements were functions of days of the week, with highest values occurring on Fridays and lowest ones on Sundays. Spatial variations associated to BC levels are very different from one site to another, revealing different types of sources with strong variations at the regional scale. It appears that mean BC concentrations in Dakar are lower by a factor of two, compared to those observed in Bamako, but remain higher than in some other West African sites (e.g. Cotonou, Yaounde). Overall, BC concentrations in our different sites are comparable to reported European and Asian megacity levels. Finally, using measured BC/PM2.5 ratios, we have

  20. A Comprehensive Statistically-Based Method to Interpret Real-Time Flowing Measurements

    SciTech Connect

    Pinan Dawkrajai; Keita Yoshioka; Analis A. Romero; Ding Zhu; A.D. Hill; Larry W. Lake

    2005-10-01

    This project is motivated by the increasing use of distributed temperature sensors for real-time monitoring of complex wells (horizontal, multilateral and multi-branching wells) to infer the profiles of oil, gas, and water entry. Measured information can be used to interpret flow profiles along the wellbore including junction and build section. In this second project year, we have completed a forward model to predict temperature and pressure profiles in complex wells. As a comprehensive temperature model, we have developed an analytical reservoir flow model which takes into account Joule-Thomson effects in the near well vicinity and multiphase non-isothermal producing wellbore model, and couples those models accounting mass and heat transfer between them. For further inferences such as water coning or gas evaporation, we will need a numerical non-isothermal reservoir simulator, and unlike existing (thermal recovery, geothermal) simulators, it should capture subtle temperature change occurring in a normal production. We will show the results from the analytical coupled model (analytical reservoir solution coupled with numerical multi-segment well model) to infer the anomalous temperature or pressure profiles under various conditions, and the preliminary results from the numerical coupled reservoir model which solves full matrix including wellbore grids. We applied Ramey's model to the build section and used an enthalpy balance to infer the temperature profile at the junction. The multilateral wellbore temperature model was applied to a wide range of cases varying fluid thermal properties, absolute values of temperature and pressure, geothermal gradients, flow rates from each lateral, and the trajectories of each build section.

  1. Real-time rainfall measurement in the City of Charlotte and Mecklenburg County, North Carolina

    USGS Publications Warehouse

    Hazell, W.F.; Bales, Jerad D.

    1997-01-01

    The U.S. Geological Survey (USGS) has measured rainfall at various locations in Mecklenburg County, North Carolina, since 1963. Between 1992 and 1997, the USGS, in cooperation with Charlotte Stormwater Services, installed 43 raingages throughout Mecklengburg County and adjoining counties. These 43 raingages, combined with three previously installed gages, compose a data-collection network that provides detailed, accurate information on rainfall throughout the county.

  2. Percutaneous Radiofrequency Ablation of Osteoid Osteomas with Use of Real-Time Needle Guidance for Accurate Needle Placement: A Pilot Study

    SciTech Connect

    Busser, Wendy M. H. Hoogeveen, Yvonne L.; Veth, Rene P. H.; Schreuder, H. W. Bart; Balguid, Angelique; Renema, W. KlaasJan; SchultzeKool, Leo J.

    2011-02-15

    Purpose: To evaluate the accuracy and technical success of positioning a radiofrequency ablation (RFA) electrode in osteoid osteomas by use of a new real-time needle guidance technology combining cone-beam computed tomography (CT) and fluoroscopy. Materials and Methods: Percutaneous RFA of osteoid osteomas was performed in five patients (median age 18 years), under general anesthesia, with the use of cone-beam CT and fluoroscopic guidance for electrode positioning. The outcome parameters were technical success, meaning correct needle placement in the nidus; accuracy defined as the deviation (in mm) from the center of the nidus; and clinical outcome at follow-up. Results: In all five cases, positioning was possible within 3 mm of the determined target location (median nidus size 6.8 mm; range 5-10.2 mm). All procedures were technically successful. All patients were free of pain at clinical follow-up. No complications were observed. Conclusion: Real-time fluoroscopy needle guidance based on cone-beam CT is a useful tool to accurately position radiofrequency needles for minimally invasive treatment of osteoid osteomas.

  3. Fast and Accurate Data Extraction for Near Real-Time Registration of 3-D Ultrasound and Computed Tomography in Orthopedic Surgery.

    PubMed

    Brounstein, Anna; Hacihaliloglu, Ilker; Guy, Pierre; Hodgson, Antony; Abugharbieh, Rafeef

    2015-12-01

    Automatic, accurate and real-time registration is an important step in providing effective guidance and successful anatomic restoration in ultrasound (US)-based computer assisted orthopedic surgery. We propose a method in which local phase-based bone surfaces, extracted from intra-operative US data, are registered to pre-operatively segmented computed tomography data. Extracted bone surfaces are downsampled and reinforced with high curvature features. A novel hierarchical simplification algorithm is used to further optimize the point clouds. The final point clouds are represented as Gaussian mixture models and iteratively matched by minimizing the dissimilarity between them using an L2 metric. For 44 clinical data sets from 25 pelvic fracture patients and 49 phantom data sets, we report mean surface registration accuracies of 0.31 and 0.77 mm, respectively, with an average registration time of 1.41 s. Our results suggest the viability and potential of the chosen method for real-time intra-operative registration in orthopedic surgery. PMID:26365924

  4. Automated Historical and Real-Time Cyclone Discovery With Multimodal Remote Satellite Measurements

    NASA Astrophysics Data System (ADS)

    Ho, S.; Talukder, A.; Liu, T.; Tang, W.; Bingham, A.

    2008-12-01

    methodology can be applied to (i) historical data to support Earth scientists in climate modeling, cyclonic-climate interactions, and obtain a better understanding of the cause and effects of cyclone (e.g. cyclo-genesis), and (ii) automatic cyclone discovery in near real-time using streaming satellite to support and improve the planning of global cyclone field campaigns. Additional satellite data from GOES and other orbiting satellites can be easily assimilated and integrated into our automated cyclone detection and tracking module to improve the temporal tracking accuracy of cyclones down to ½ hr and reduce the incidence of false alarms.

  5. Unmanned Airborne System Deployment at Turrialba Volcano for Real Time Eruptive Cloud Measurements

    NASA Astrophysics Data System (ADS)

    Diaz, J. A.; Pieri, D. C.; Fladeland, M. M.; Bland, G.; Corrales, E.; Alan, A., Jr.; Alegria, O.; Kolyer, R.

    2015-12-01

    The development of small unmanned aerial systems (sUAS) with a variety of instrument packages enables in situ and proximal remote sensing measurements of volcanic plumes, even when the active conditions of the volcano do not allow volcanologists and emergency response personnel to get too close to the erupting crater. This has been demonstrated this year by flying a sUAS through the heavy ash driven erupting volcanic cloud of Turrialba Volcano, while conducting real time in situ measurement of gases over the crater summit. The event also achieved the collection of newly released ash samples from the erupting volcano. The interception of the Turrialba ash cloud occurred during the CARTA 2015 field campaign carried out as part of an ongoing program for remote sensing satellite calibration and validation purposes, using active volcanic plumes. These deployments are timed to support overflights of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) onboard the NASA Terra satellite on a bimonthly basis using airborne platforms such as tethered balloons, free-flying fixed wing small UAVs at altitudes up to 12.5Kft ASL within about a 5km radius of the summit crater. The onboard instrument includes the MiniGas payload which consists of an array of single electrochemical and infrared gas detectors (SO2, H2S CO2), temperature, pressure, relative humidity and GPS sensors, all connected to an Arduino-based board, with data collected at 1Hz. Data are both stored onboard and sent by telemetry to the ground operator within a 3 km range. The UAV can also carry visible and infrared cameras as well as other payloads, such as a UAV-MS payload that is currently under development for mass spectrometer-based in situ measurements. The presentation describes the ongoing UAV- based in situ remote sensing validation program at Turrialba Volcano, the results of a fly-through the eruptive cloud, as well as future plans to continue these efforts. Work presented here was

  6. Detectors and electronics for real time measurement of radiation dose and quality using the variance method

    NASA Astrophysics Data System (ADS)

    Hsu, Wen-Hsing

    The product of the radiation dose and radiation quality indicates the biological consequences of radiation exposure. Therefore, quantifying both radiation dose and radiation quality is important to biological experiments as well as radiation protection. A small, specialized amplifier based on commercial ICs was developed to measure the radiation dose and quality in real-time using a microdosimetric detector, operated in the current mode, and the variance method. The random nature of radiation induces variance in the dose (in a small volume such as that of cell or DNA) for a specific radiation field that is proportional to the radiation quality. The charges from the microdosimetric detector, operated in the current mode, were repeatedly collected for a fixed period of time for 20 cycles of 100 integrations, and processed by the specialized amplifier to produce signals of pulse height between 0 and 10 volts. These signals with various amplitudes, which are proportional to the channel number, were then recorded by the MCA and stored in a computer. FORTRAN programs written in this study then calculated the average dose and the average dose variance from the stored data. Benchmarks of different brand's ICs were conducted to select a component with the best performance versus cost. The specialized amplifier showed the following characteristics: low input capacitance, low output impedance, adjustable integration time for controlling the amount of charge collected from the detector, linearity of system response to input currents, adjustable gain control, and low background noise. Standardized procedures of constructing a functional device (the specialized amplifier) were established, including arrangements of circuit diagram, processing of a printed circuit board, and construction of an aluminum-shielding box that served as a united ground point. In addition, procedures for determining the inner dimensions of the detector using radiography are also presented along with

  7. Development of a downhole tool measuring real-time concentration of ionic tracers and pH in geothermal reservoirs

    NASA Astrophysics Data System (ADS)

    Hess, Ryan F.; Boyle, Timothy J.; Limmer, Steven; Yelton, William G.; Bingham, Samuel; Stillman, Greg; Lindblom, Scott; Cieslewski, Grzegorz

    2014-06-01

    For enhanced or Engineered Geothermal Systems (EGS) geothermal brine is pumped to the surface via the production wells, the heat extracted to turn a turbine to generate electricity, and the spent brine re-injected via injection wells back underground. If designed properly, the subsurface rock formations will lead this water back to the extraction well as heated brine. Proper monitoring of these geothermal reservoirs is essential for developing and maintaining the necessary level of productivity of the field. Chemical tracers are commonly used to characterize the fracture network and determine the connectivity between the injection and production wells. Currently, most tracer experiments involve injecting the tracer at the injection well, manually collecting liquid samples at the wellhead of the production well, and sending the samples off for laboratory analysis. While this method provides accurate tracer concentration data at very low levels of detection, it does not provide information regarding the location of the fractures which were conducting the tracer between wellbores. Sandia is developing a high-temperature electrochemical sensor capable of measuring tracer concentrations and pH downhole on a wireline tool. The goal of this effort is to collect real-time pH and ionic tracer concentration data at temperatures up to 225 °C and pressures up to 3000 psi. In this paper, a prototype electrochemical sensor and the initial data obtained will be presented detailing the measurement of iodide tracer concentrations at high temperature and pressure in a newly developed laboratory scale autoclave.

  8. Real-Time Detection and Measurement of Eye Features from Color Images

    PubMed Central

    Borza, Diana; Darabant, Adrian Sergiu; Danescu, Radu

    2016-01-01

    The accurate extraction and measurement of eye features is crucial to a variety of domains, including human-computer interaction, biometry, and medical research. This paper presents a fast and accurate method for extracting multiple features around the eyes: the center of the pupil, the iris radius, and the external shape of the eye. These features are extracted using a multistage algorithm. On the first stage the pupil center is localized using a fast circular symmetry detector and the iris radius is computed using radial gradient projections, and on the second stage the external shape of the eye (of the eyelids) is determined through a Monte Carlo sampling framework based on both color and shape information. Extensive experiments performed on a different dataset demonstrate the effectiveness of our approach. In addition, this work provides eye annotation data for a publicly-available database. PMID:27438838

  9. Real-Time Detection and Measurement of Eye Features from Color Images.

    PubMed

    Borza, Diana; Darabant, Adrian Sergiu; Danescu, Radu

    2016-01-01

    The accurate extraction and measurement of eye features is crucial to a variety of domains, including human-computer interaction, biometry, and medical research. This paper presents a fast and accurate method for extracting multiple features around the eyes: the center of the pupil, the iris radius, and the external shape of the eye. These features are extracted using a multistage algorithm. On the first stage the pupil center is localized using a fast circular symmetry detector and the iris radius is computed using radial gradient projections, and on the second stage the external shape of the eye (of the eyelids) is determined through a Monte Carlo sampling framework based on both color and shape information. Extensive experiments performed on a different dataset demonstrate the effectiveness of our approach. In addition, this work provides eye annotation data for a publicly-available database. PMID:27438838

  10. Identification and evaluation of new reference genes in Gossypium hirsutum for accurate normalization of real-time quantitative RT-PCR data

    PubMed Central

    2010-01-01

    Background Normalizing through reference genes, or housekeeping genes, can make more accurate and reliable results from reverse transcription real-time quantitative polymerase chain reaction (qPCR). Recent studies have shown that no single housekeeping gene is universal for all experiments. Thus, suitable reference genes should be the first step of any qPCR analysis. Only a few studies on the identification of housekeeping gene have been carried on plants. Therefore qPCR studies on important crops such as cotton has been hampered by the lack of suitable reference genes. Results By the use of two distinct algorithms, implemented by geNorm and NormFinder, we have assessed the gene expression of nine candidate reference genes in cotton: GhACT4, GhEF1α5, GhFBX6, GhPP2A1, GhMZA, GhPTB, GhGAPC2, GhβTUB3 and GhUBQ14. The candidate reference genes were evaluated in 23 experimental samples consisting of six distinct plant organs, eight stages of flower development, four stages of fruit development and in flower verticils. The expression of GhPP2A1 and GhUBQ14 genes were the most stable across all samples and also when distinct plants organs are examined. GhACT4 and GhUBQ14 present more stable expression during flower development, GhACT4 and GhFBX6 in the floral verticils and GhMZA and GhPTB during fruit development. Our analysis provided the most suitable combination of reference genes for each experimental set tested as internal control for reliable qPCR data normalization. In addition, to illustrate the use of cotton reference genes we checked the expression of two cotton MADS-box genes in distinct plant and floral organs and also during flower development. Conclusion We have tested the expression stabilities of nine candidate genes in a set of 23 tissue samples from cotton plants divided into five different experimental sets. As a result of this evaluation, we recommend the use of GhUBQ14 and GhPP2A1 housekeeping genes as superior references for normalization of gene

  11. Internal flow measurements of the SSME fuel preburner injector element using real time neutron radiography

    NASA Technical Reports Server (NTRS)

    Lindsay, John T.; Elam, Sandy; Koblish, Ted; Lee, Phil; Mcauliffe, Dave

    1990-01-01

    Due to observations of unsteady flow in the Space Shuttle Main Engine fuel preburner injector element, several flow studies have been performed. Real time neutron radiography tests were recently completed. This technique provided real time images of MiL-c-7024 and Freon-22 flow through an aluminum liquid oxygen post model at three back pressures (0, 150, and 545 psig) and pressure drops up to 1000 psid. Separated flow appeared only while operating at back pressures of 0 and 150 psig. The behavior of separated flow was similar to that observed for water in a 3x acrylic model of the LOX post. On the average, separated flow appeared to reattach near the exit of the post when the ratio of pressure drop to supply pressure was about 0.75.

  12. XpertTrack: Precision Autonomous Measuring Device Developed for Real Time Shipments Tracker.

    PubMed

    Viman, Liviu; Daraban, Mihai; Fizesan, Raul; Iuonas, Mircea

    2016-01-01

    This paper proposes a software and hardware solution for real time condition monitoring applications. The proposed device, called XpertTrack, exchanges data through the GPRS protocol over a GSM network and monitories temperature and vibrations of critical merchandise during commercial shipments anywhere on the globe. Another feature of this real time tracker is to provide GPS and GSM positioning with a precision of 10 m or less. In order to interpret the condition of the merchandise, the data acquisition, analysis and visualization are done with 0.1 °C accuracy for the temperature sensor, and 10 levels of shock sensitivity for the acceleration sensor. In addition to this, the architecture allows increasing the number and the types of sensors, so that companies can use this flexible solution to monitor a large percentage of their fleet. PMID:26978360

  13. XpertTrack: Precision Autonomous Measuring Device Developed for Real Time Shipments Tracker

    PubMed Central

    Viman, Liviu; Daraban, Mihai; Fizesan, Raul; Iuonas, Mircea

    2016-01-01

    This paper proposes a software and hardware solution for real time condition monitoring applications. The proposed device, called XpertTrack, exchanges data through the GPRS protocol over a GSM network and monitories temperature and vibrations of critical merchandise during commercial shipments anywhere on the globe. Another feature of this real time tracker is to provide GPS and GSM positioning with a precision of 10 m or less. In order to interpret the condition of the merchandise, the data acquisition, analysis and visualization are done with 0.1 °C accuracy for the temperature sensor, and 10 levels of shock sensitivity for the acceleration sensor. In addition to this, the architecture allows increasing the number and the types of sensors, so that companies can use this flexible solution to monitor a large percentage of their fleet. PMID:26978360

  14. Real-time measurement and audit of radiation dose to patients undergoing computed radiography.

    PubMed

    Vano, Eliseo; Fernandez, Jose Miguel; Ten, Jose Ignacio; Guibelalde, Eduardo; Gonzalez, Luciano; Pedrosa, Cesar S A

    2002-10-01

    A real-time patient dose monitoring system for auditing computed radiography is described. Technical data from each exposure and for every examination type are collected and sent by a network to a workstation, which calculates the moving average values of entrance skin dose and dose-area product from the 10 most recently examined patients. Comparison of averages with reference values generates warning messages if reference values are exceeded, prompting corrective action if necessary. PMID:12355017

  15. High-resolution real-time 3D shape measurement on a portable device

    NASA Astrophysics Data System (ADS)

    Karpinsky, Nikolaus; Hoke, Morgan; Chen, Vincent; Zhang, Song

    2013-09-01

    Recent advances in technology have enabled the acquisition of high-resolution 3D models in real-time though the use of structured light scanning techniques. While these advances are impressive, they require large amounts of computing power, thus being limited to using large desktop computers with high end CPUs and sometimes GPUs. This is undesirable in making high-resolution real-time 3D scanners ubiquitous in our mobile lives. To address this issue, this work describes and demonstrates a real-time 3D scanning system that is realized on a mobile device, namely a laptop computer, which can achieve speeds of 20fps 3D at a resolution of 640x480 per frame. By utilizing a graphics processing unit (GPU) as a multipurpose parallel processor, along with a parallel phase shifting technique, we are able to realize the entire 3D processing pipeline in parallel. To mitigate high speed camera transfer problems, which typically require a dedicated frame grabber, we make use of USB 3.0 along with direct memory access (DMA) to transfer camera images to the GPU. To demonstrate the effectiveness of the technique, we experiment with the scanner on both static geometry of a statue and dynamic geometry of a deforming material sample in front of the system.

  16. Real-time measurement of flow rate in microfluidic devices using a cantilever-based optofluidic sensor.

    PubMed

    Cheri, Mohammad Sadegh; Latifi, Hamid; Sadeghi, Jalal; Moghaddam, Mohammadreza Salehi; Shahraki, Hamidreza; Hajghassem, Hasan

    2014-01-21

    Real-time and accurate measurement of flow rate is an important reqirement in lab on a chip (LOC) and micro total analysis system (μTAS) applications. In this paper, we present an experimental and numerical investigation of a cantilever-based optofluidic flow sensor for this purpose. Two sensors with thin and thick cantilevers were fabricated by engraving a 2D pattern of cantilever/base on two polymethylmethacrylate (PMMA) slabs using a CO2 laser system and then casting a 2D pattern with polydimethylsiloxane (PDMS). The basic working principle of the sensor is the fringe shift of the Fabry-Pérot (FP) spectrum due to a changing flow rate. A Finite Element Method (FEM) is used to solve the three dimensional (3D) Navier-Stokes and structural deformation equations to simulate the pressure distribution, velocity and cantilever deflection results of the flow in the channel. The experimental results show that the thin and thick cantilevers have a minimum detectable flow change of 1.3 and 4 (μL min(-1)) respectively. In addition, a comparison of the numerical and experimental deflection of the cantilever has been done to obtain the effective Young's modulus of the thin and thick PDMS cantilevers. PMID:24291805

  17. Development of a methodology to measure the effect of ergot alkaloids on forestomach motility using real-time wireless telemetry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of these experiments were to characterize rumen motility patterns of cattle fed once daily using a real-time wireless telemetry system, determine when to measure rumen motility with this system, and determine the effect of ruminal dosing of ergot alkaloids on rumen motility. Ruminally...

  18. REAL-TIME MEASUREMENT OF AIRWAY RESPONSES TO SULOFUR DIOXIDE (SO2) IN AN INTACT, AWAKE GUINEA PIG MODEL

    EPA Science Inventory

    Real-time measurment of airway responses to Sulfur Dioxide (SO2) in an intact, awake guinea pig model. J Stanek1,2, Q Krantz2, J Nolan2, D Winsett2, W Watkinson2, and D Costa2. 1College of Veterinary Medicine, NCSU, Raleigh, NC, USA; 2Pulmonary Toxicology Branch, ETD, NHEERL, US...

  19. Real-time 3-D shape measurement with composite phase-shifting fringes and multi-view system.

    PubMed

    Tao, Tianyang; Chen, Qian; Da, Jian; Feng, Shijie; Hu, Yan; Zuo, Chao

    2016-09-01

    In recent years, fringe projection has become an established and essential method for dynamic three-dimensional (3-D) shape measurement in different fields such as online inspection and real-time quality control. Numerous high-speed 3-D shape measurement methods have been developed by either employing high-speed hardware, minimizing the number of pattern projection, or both. However, dynamic 3-D shape measurement of arbitrarily-shaped objects with full sensor resolution without the necessity of additional pattern projections is still a big challenge. In this work, we introduce a high-speed 3-D shape measurement technique based on composite phase-shifting fringes and a multi-view system. The geometry constraint is adopted to search the corresponding points independently without additional images. Meanwhile, by analysing the 3-D position and the main wrapped phase of the corresponding point, pairs with an incorrect 3-D position or a considerable phase difference are effectively rejected. All of the qualified corresponding points are then corrected, and the unique one as well as the related period order is selected through the embedded triangular wave. Finally, considering that some points can only be captured by one of the cameras due to the occlusions, these points may have different fringe orders in the two views, so a left-right consistency check is employed to eliminate those erroneous period orders in this case. Several experiments on both static and dynamic scenes are performed, verifying that our method can achieve a speed of 120 frames per second (fps) with 25-period fringe patterns for fast, dense, and accurate 3-D measurement. PMID:27607632

  20. Real-time measurements of plasma/surface interaction by plasma-amplified photoelectron detection

    NASA Astrophysics Data System (ADS)

    Selwyn, G. S.; Ai, B. D.; Singh, J.

    1988-06-01

    A new method, based on the photoelectric effect, is described for real-time, in situ monitoring of metal or semiconductor surfaces during plasma exposure. As an example of the application of this technique, the effect of both sputter and reactive gas plasma exposure is studied for graphite, silicon, and aluminum surfaces. Results are consistent with the formation of a surface-passivating layer of fluoride on aluminum and penetration of fluorine into the silicon bulk during exposure to the CF4+Ar etching plasma. An application of this technique for endpoint detection monitoring is described.

  1. A real-time microprocessor QRS detector system with a 1-ms timing accuracy for the measurement of ambulatory HRV.

    PubMed

    Ruha, A; Sallinen, S; Nissilä, S

    1997-03-01

    The design, test methods and results of an ambulatory QRS detector are presented. The device is intended for the accurate measurement of heart rate variability (HRV) and reliable QRS detection in both ambulatory and clinical use. The aim of the design work was to achieve high QRS detection performance in terms of timing accuracy and reliability, without compromising the size and power consumption of the device. The complete monitor system consists of a host computer and the detector unit. The detector device is constructed of a commonly available digital signal processing (DSP) microprocessor and other components. The QRS detection algorithm uses optimized prefiltering in conjunction with a matched filter and dual edge threshold detection. The purpose of the prefiltering is to attenuate various noise components in order to achieve improved detection reliability. The matched filter further improves signal-to-noise ratio (SNR) and symmetries the QRS complex for the threshold detection, which is essential in order to achieve the desired performance. The decision for detection is made in real-time and no search-back method is employed. The host computer is used to configure the detector unit, which includes the setting of the matched filter impulse response, and in the retrieval and postprocessing of the measurement results. The QRS detection timing accuracy and detection reliability of the detector system was tested with an artificially generated electrocardiogram (ECG) signal corrupted with various noise types and a timing standard deviation of less than 1 ms was achieved with most noise types and levels similar to those encountered in real measurements. A QRS detection error rate (ER) of 0.1 and 2.2% was achieved with records 103 and 105 from the MIT-BIH Arrhythmia database, respectively. PMID:9216129

  2. DEVELOPMENT OF AN ON-LINE, REAL-TIME ALPHA RADIATION MEASURING INSTRUMENT FOR LIQUID STREAMS

    SciTech Connect

    Unknown

    1999-06-16

    Thermo Power Corporation has proven the technical viability of an on-line, real-time alpha radionuclide instrument for aqueous sample analysis through laboratory and initial field tests of the instrument. The instrument has been shown to be isotonically sensitive to extremely low (ten parts per trillion, or femto Curies per liter) levels of a broad range of radioisotopes. Performance enhancement and other scaling data obtained during the course of this investigation have shown that on-line, real-time operation is possible, with a sub 30-minute response time analyzing 20 ppb (30 pCi/1) natural uranium. Now that these initial field tests in Oak Ridge, Tennessee have been successfully completed, Thermo Power plans to conduct comprehensive field tests of the instrument. The purpose of these endurance tests will be to determine the endurance characteristics of the Thermo Alpha Monitor for Water when it is used by non-Thermo Power personnel in a series of one or more extended field tests. Such endurance testing is the vital next step towards the commercialization of the Alpha Monitor. Subsequently, it will be possible to provide the DOE with an instrument that has the capability of obtaining rapid feedback about the concentrations of alpha-emitting isotope contamination in effluent water streams (Subsurface Contaminants Focus Area). It will also be useful for process control of remediation and D and D operations such as monitoring scrubber/rinse water radioactivity levels (Mixed Waste, Plutonium and D and D Focus Areas).

  3. An FPGA Architecture for Extracting Real-Time Zernike Coefficients from Measured Phase Gradients

    NASA Astrophysics Data System (ADS)

    Moser, Steven; Lee, Peter; Podoleanu, Adrian

    2015-04-01

    Zernike modes are commonly used in adaptive optics systems to represent optical wavefronts. However, real-time calculation of Zernike modes is time consuming due to two factors: the large factorial components in the radial polynomials used to define them and the large inverse matrix calculation needed for the linear fit. This paper presents an efficient parallel method for calculating Zernike coefficients from phase gradients produced by a Shack-Hartman sensor and its real-time implementation using an FPGA by pre-calculation and storage of subsections of the large inverse matrix. The architecture exploits symmetries within the Zernike modes to achieve a significant reduction in memory requirements and a speed-up of 2.9 when compared to published results utilising a 2D-FFT method for a grid size of 8×8. Analysis of processor element internal word length requirements show that 24-bit precision in precalculated values of the Zernike mode partial derivatives ensures less than 0.5% error per Zernike coefficient and an overall error of <1%. The design has been synthesized on a Xilinx Spartan-6 XC6SLX45 FPGA. The resource utilisation on this device is <3% of slice registers, <15% of slice LUTs, and approximately 48% of available DSP blocks independent of the Shack-Hartmann grid size. Block RAM usage is <16% for Shack-Hartmann grid sizes up to 32×32.

  4. Non-contact Real-time heart rate measurements based on high speed circuit technology research

    NASA Astrophysics Data System (ADS)

    Wu, Jizhe; Liu, Xiaohua; Kong, Lingqin; Shi, Cong; Liu, Ming; Hui, Mei; Dong, Liquan; Zhao, Yuejin

    2015-08-01

    In recent years, morbidity and mortality of the cardiovascular or cerebrovascular disease, which threaten human health greatly, increased year by year. Heart rate is an important index of these diseases. To address this status, the paper puts forward a kind of simple structure, easy operation, suitable for large populations of daily monitoring non-contact heart rate measurement. In the method we use imaging equipment video sensitive areas. The changes of light intensity reflected through the image grayscale average. The light change is caused by changes in blood volume. We video the people face which include the sensitive areas (ROI), and use high-speed processing circuit to save the video as AVI format into memory. After processing the whole video of a period of time, we draw curve of each color channel with frame number as horizontal axis. Then get heart rate from the curve. We use independent component analysis (ICA) to restrain noise of sports interference, realized the accurate extraction of heart rate signal under the motion state. We design an algorithm, based on high-speed processing circuit, for face recognition and tracking to automatically get face region. We do grayscale average processing to the recognized image, get RGB three grayscale curves, and extract a clearer pulse wave curves through independent component analysis, and then we get the heart rate under the motion state. At last, by means of compare our system with Fingertip Pulse Oximeter, result show the system can realize a more accurate measurement, the error is less than 3 pats per minute.

  5. Real-time measurement of RFR energy distribution in the Macaca mulatta head

    SciTech Connect

    Burr, J.G.; Krupp, J.H.

    1980-01-01

    Temperature increases due to absorption of 1.2 GHz, CW, 70 mW/cm2, radio frequency (RF) energy, were measured in 3.3-cm-radius homogeneous muscle-equivalent spheres, M. mulatta cadaver heads (both detached from and attached to the body) and living, anesthetized M. mulatta heads. Temperatures were measured with a Vitek, Model 101 Electrothermia Monitor and temperature distributions were compared to theoretical predictions from a thermal-response model of a simulated cranial structure. The results show that the thermal response model accurately predicts the temperature distribution in muscle-equivalent spheres, the distribution of temperature in detached M. mulatta heads when exposed from the back of the head, and the distribution of temperature in attached M. mulatta cadaver heads for animals oriented with body parallel to the H-field. The temperature distribution in the detached M. mulatta heads varies markedly with exposure orientation, ie, facing forward, backward, or to the side. The orientation of the M. mulatta cadaver body significantly affects the temperature distribution in the head - with H-field orientation showing high, nonuniform values, and E-field orientation showing low, uniform values. In live animals blood flow produces a significant short-term effect on the temperature distribution in the midbrain, but not the cortex. Midbrain temperatures are both significantly higher and lower than the comparable cadaver measurements, depending on location.

  6. Feedback system for divertor impurity seeding based on real-time measurements of surface heat flux in the Alcator C-Mod tokamak.

    PubMed

    Brunner, D; Burke, W; Kuang, A Q; LaBombard, B; Lipschultz, B; Wolfe, S

    2016-02-01

    Mitigation of the intense heat flux to the divertor is one of the outstanding problems in fusion energy. One technique that has shown promise is impurity seeding, i.e., the injection of low-Z gaseous impurities (typically N2 or Ne) to radiate and dissipate the power before it arrives to the divertor target plate. To this end, the Alcator C-Mod team has created a first-of-its-kind feedback system to control the injection of seed gas based on real-time surface heat flux measurements. Surface thermocouples provide real-time measurements of the surface temperature response to the plasma heat flux. The surface temperature measurements are inputted into an analog computer that "solves" the 1-D heat transport equation to deliver accurate, real-time signals of the surface heat flux. The surface heat flux signals are sent to the C-Mod digital plasma control system, which uses a proportional-integral-derivative (PID) algorithm to control the duty cycle demand to a pulse width modulated piezo valve, which in turn controls the injection of gas into the private flux region of the C-Mod divertor. This paper presents the design and implementation of this new feedback system as well as initial results using it to control divertor heat flux. PMID:26931846

  7. Feedback system for divertor impurity seeding based on real-time measurements of surface heat flux in the Alcator C-Mod tokamak

    NASA Astrophysics Data System (ADS)

    Brunner, D.; Burke, W.; Kuang, A. Q.; LaBombard, B.; Lipschultz, B.; Wolfe, S.

    2016-02-01

    Mitigation of the intense heat flux to the divertor is one of the outstanding problems in fusion energy. One technique that has shown promise is impurity seeding, i.e., the injection of low-Z gaseous impurities (typically N2 or Ne) to radiate and dissipate the power before it arrives to the divertor target plate. To this end, the Alcator C-Mod team has created a first-of-its-kind feedback system to control the injection of seed gas based on real-time surface heat flux measurements. Surface thermocouples provide real-time measurements of the surface temperature response to the plasma heat flux. The surface temperature measurements are inputted into an analog computer that "solves" the 1-D heat transport equation to deliver accurate, real-time signals of the surface heat flux. The surface heat flux signals are sent to the C-Mod digital plasma control system, which uses a proportional-integral-derivative (PID) algorithm to control the duty cycle demand to a pulse width modulated piezo valve, which in turn controls the injection of gas into the private flux region of the C-Mod divertor. This paper presents the design and implementation of this new feedback system as well as initial results using it to control divertor heat flux.

  8. A luminescent assay for real-time measurements of receptor endocytosis in living cells.

    PubMed

    Robers, Matthew B; Binkowski, Brock F; Cong, Mei; Zimprich, Chad; Corona, Cesear; McDougall, Mark; Otto, George; Eggers, Christopher T; Hartnett, Jim; Machleidt, Thomas; Fan, Frank; Wood, Keith V

    2015-11-15

    Ligand-mediated endocytosis is a key autoregulatory mechanism governing the duration and intensity of signals emanating from cell surface receptors. Due to the mechanistic complexity of endocytosis and its emerging relevance in disease, simple methods capable of tracking this dynamic process in cells have become increasingly desirable. We have developed a bioluminescent reporter technology for real-time analysis of ligand-mediated receptor endocytosis using genetic fusions of NanoLuc luciferase with various G-protein-coupled receptors (GPCRs). This method is compatible with standard microplate formats, which should decrease work flows for high-throughput screens. This article also describes the application of this technology to endocytosis of epidermal growth factor receptor (EGFR), demonstrating potential applicability of the method beyond GPCRs. PMID:26278171

  9. Real-time measurement of ice growth during simulated and natural icing conditions using ultrasonic pulse-echo techniques

    NASA Technical Reports Server (NTRS)

    Hansman, R. J., Jr.; Kirby, M. S.

    1986-01-01

    Results of tests to measure ice accretion in real-time using ultrasonic pulse-echo techniques are presented. Tests conducted on a 10.2 cm diameter cylinder exposed to simulated icing conditions in the NASA Lewis Icing Research Tunnel and on an 11.4 cm diameter cylinder exposed to natural icing conditions in flight are described. An accuracy of + or - 0.5 mm is achieved for real-time ice thickness measurements. Ice accretion rate is determined by differentiating ice thickness with respect to time. Icing rates measured during simulated and natural icing conditions are compared and related to icing cloud parameters. The ultrasonic signal characteristics are used to detect the presence of surface water on the accreting ice shape and thus to distinguish between dry ice growth and wet growth. The surface roughness of the accreted ice is shown to be related to the width of the echo signal received from the ice surface.

  10. The Real-Time, High Precision Phase Difference Measurement of Electron Density in HL-2A Tokamak

    NASA Astrophysics Data System (ADS)

    Ding, Baogang; Wu, Tongyu; Li, Shiping; Zhou, Yan; Yin, Zejie

    2015-09-01

    This paper introduces a real-time high precision measurement of phase difference based on Field Programmable Gate Array (FPGA) technology, which has been successfully applied to laser grating interference measurement and real-time feedback of plasma electron density in HL-2A tokamak. It can track the changes of electron density while setting the starting point of the density curve to zero. In a laboratory test, the measuring accuracy of phase difference is less than 0.1°, the time resolution is 80 ns, and the feedback delay is 180 μs. supported by National Natural Science Foundation of China (Nos. 11375195, 11075048) and the National Magnetic Confinement Fusion Science Program of China (No. 2013GB104003)

  11. Real-Time Visualization of Tissue Surface Biochemical Features Derived From Fluorescence Lifetime Measurements.

    PubMed

    Gorpas, Dimitris; Ma, Dinglong; Bec, Julien; Yankelevich, Diego R; Marcu, Laura

    2016-08-01

    Fiber based fluorescence lifetime imaging has shown great potential for intraoperative diagnosis and guidance of surgical procedures. Here we describe a novel method addressing a significant challenge for the practical implementation of this technique, i.e., the real-time display of the quantified biochemical or functional tissue properties superimposed on the interrogated area. Specifically, an aiming beam (450 nm) generated by a continuous-wave laser beam was merged with the pulsed fluorescence excitation light in a single delivery/collection fiber and then imaged and segmented using a color-based algorithm. We demonstrate that this approach enables continuous delineation of the interrogated location and dynamic augmentation of the acquired frames with the corresponding fluorescence decay parameters. The method was evaluated on a fluorescence phantom and fresh tissue samples. Current results demonstrate that 34 frames per second can be achieved for augmenting videos of 640 × 512 pixels resolution. Also we show that the spatial resolution of the fluorescence lifetime map depends on the tissue optical properties, the scanning speed, and the frame rate. The dice similarity coefficient between the fluorescence phantom and the reconstructed maps was estimated to be as high as 93%. The reported method could become a valuable tool for augmenting the surgeon's field of view with diagnostic information derived from the analysis of fluorescence lifetime data in real-time using handheld, automated, or endoscopic scanning systems. Current method provides also a means for maintaining the tissue light exposure within safety limits. This study provides a framework for using an aiming beam with other point spectroscopy applications. PMID:26890641

  12. An advanced vision-based system for real-time displacement measurement of high-rise buildings

    NASA Astrophysics Data System (ADS)

    Lee, Jong-Han; Ho, Hoai-Nam; Shinozuka, Masanobu; Lee, Jong-Jae

    2012-12-01

    This paper introduces an advanced vision-based system for dynamic real-time displacement measurement of high-rise buildings using a partitioning approach. The partitioning method is based on the successive estimation of relative displacements and rotational angles at several floors using a multiple vision-based displacement measurement system. In this study, two significant improvements were made to realize the partitioning method: (1) time synchronization, (2) real-time dynamic measurement. Displacement data and time synchronization information are wirelessly transferred via a network using the TCP/IP protocol. The time synchronization process is periodically conducted by the master system to guarantee the system time at the master and slave systems are synchronized. The slave system is capable of dynamic real-time measurement and it is possible to economically expand measurement points at slave levels using commercial devices. To verify the accuracy and feasibility of the synchronized multi-point vision-based system and partitioning approach, many laboratory tests were carried out on a three-story steel frame model. Furthermore, several tests were conducted on a five-story steel frame tower equipped with a hybrid mass damper to experimentally confirm the effectiveness of the proposed system.

  13. Real-Time Dynamic Spectrum Analysis for Plasma Electron Density and Faraday Rotation Angle Measurement on HL-2A

    NASA Astrophysics Data System (ADS)

    Ding, Baogang; Wu, Jun; Fan, Weiwei; Wu, Tongyu; Zhou, Yan; Yin, Zejie

    2015-12-01

    Electron density and Faraday rotation angle are important physical parameters in nuclear fusion research. To measure them simultaneously, the three-wave polarimeter/interferometer diagnostic system is applied. Both the final probe output signal and the reference signal contain three frequency components. The time-varying phase difference curve of each frequency component can be measured by the Real-time Dynamic Spectrum Analysis (RDSA) method based on Field-Programmable Gate Array (FPGA). The phase difference precision is better than 0.1° and the real-time feedback delay is less than 1 ms, which satisfy the requirements of HL-2A. supported by National Natural Science Foundation of China (Nos. 11375195 and 11275059) and the National Magnetic Confinement Fusion Science Program of China (Nos. 2013GB104003, 2014GB109001)

  14. Compensation for missing sensors in a real-time measurement beamformer system

    SciTech Connect

    Gee, T.; Collier, R.; Everman, K.

    1997-08-01

    In the system described in this paper, an array of hydrophones with a fixed geometry is used to make accurate underwater acoustic measurements over a large frequency range. The beamforming coefficients used to weight each sensor have been optimized over the full frequency range to provide the desired accuracy for a constant beam width and high noise reduction for the ocean environment. These coefficients must be developed for numerous angular beam widths and for several steering angles, requiring considerable time (several hours) to generate off-line using parallel digital signal processors. To make the number of coefficients manageable, the array symmetry has been utilized. When sensors are missing due to inevitable failures, this symmetry no longer exists, and a new method is required to handle the arbitrary array geometry. Also, failures can occur unexpectedly, making it unreasonable to redesign the coefficients for changes in array geometry. This paper describes a compensation method that has proven successful in regaining the desired amplitude level of the beam response without modifying the existing sensor coefficients.

  15. Purification of pharmaceutical preparations using thin-layer chromatography to obtain mass spectra with Direct Analysis in Real Time and accurate mass spectrometry.

    PubMed

    Wood, Jessica L; Steiner, Robert R

    2011-06-01

    Forensic analysis of pharmaceutical preparations requires a comparative analysis with a standard of the suspected drug in order to identify the active ingredient. Purchasing analytical standards can be expensive or unattainable from the drug manufacturers. Direct Analysis in Real Time (DART™) is a novel, ambient ionization technique, typically coupled with a JEOL AccuTOF™ (accurate mass) mass spectrometer. While a fast and easy technique to perform, a drawback of using DART™ is the lack of component separation of mixtures prior to ionization. Various in-house pharmaceutical preparations were purified using thin-layer chromatography (TLC) and mass spectra were subsequently obtained using the AccuTOF™- DART™ technique. Utilizing TLC prior to sample introduction provides a simple, low-cost solution to acquiring mass spectra of the purified preparation. Each spectrum was compared against an in-house molecular formula list to confirm the accurate mass elemental compositions. Spectra of purified ingredients of known pharmaceuticals were added to an in-house library for use as comparators for casework samples. Resolving isomers from one another can be accomplished using collision-induced dissociation after ionization. Challenges arose when the pharmaceutical preparation required an optimized TLC solvent to achieve proper separation and purity of the standard. Purified spectra were obtained for 91 preparations and included in an in-house drug standard library. Primary standards would only need to be purchased when pharmaceutical preparations not previously encountered are submitted for comparative analysis. TLC prior to DART™ analysis demonstrates a time efficient and cost saving technique for the forensic drug analysis community. Copyright © 2011 John Wiley & Sons, Ltd. PMID:21548141

  16. A sensor architecture for real-time, in situ measurement of overlake evaporation on the Laurentian Great Lakes

    NASA Astrophysics Data System (ADS)

    Kerkez, B.; Fries, K. J.; Gronewold, A.; Lenters, J. D.

    2014-12-01

    While overlake evaporation is a major component of the Great Lakes' water balance, our scientific understanding of the climatic drivers of evaporation and its effects on water levels is significantly impeded by limited data. Existing measurement methods, such as eddy covariance, are not easily implemented in offshore applications. As such, there are only a handful of sites making direct, overlake measurements of evaporation on the entire Great Lakes, where the lake surface area comprises nearly one third of the entire basin. Long-term forecasts of water levels are thus very uncertain, particularly relating to climatic forcing, which is known to be a major driver of evaporation. We present a novel sensor architecture which is deployed on buoys, both tethered and drifting, to provide real-time measurements of overlake evaporation across the Great Lakes. Our system is comprised of a hierarchy of low-power, cost-effective sensor nodes, which carry out on-board computations to estimate evaporation in real-time. An ultra-low power microcontroller samples a suite of sensors to compute evaporation based on the Bowen ratio energy budget approach. The readings are then transmitted via satellite modules to a cloud-based server infrastructure for real-time updated scientific analysis and forecasting. Initial assessment of our new satellite drifter platform indicates robust field performance, validating its use in ongoing efforts to deploy a large-scale evaporation observation network across the Great Lakes basin.

  17. Real-time measurements of crystallization processes in viscoelastic polymeric photonic crystals

    NASA Astrophysics Data System (ADS)

    Snoswell, David R. E.; Finlayson, Chris E.; Zhao, Qibin; Baumberg, Jeremy J.

    2015-11-01

    We present a study of the dynamic shear ordering of viscoelastic photonic crystals, based on core-shell polymeric composite particles. Using an adapted shear-cell arrangement, the crystalline ordering of the material under conditions of oscillatory shear is interrogated in real time, through both video imaging and from the optical transmission spectra of the cell. In order to gain a deeper understanding of the macroscopic influences of shear on the crystallization process in this solvent-free system, the development of bulk ordering is studied as a function of the key parameters including duty cycle and shear-strain magnitude. In particular, optimal ordering is observed from a prerandomized sample at shear strains of around 160%, for 1-Hz oscillations. This ordering reaches completion over time scales of order 10 s. These observations suggest significant local strains are needed to drive nanoparticles through energy barriers, and that local creep is needed to break temporal symmetry in such high-viscosity nanoassemblies. Crystal shear-melting effects are also characterized under conditions of constant shear rate. These quantitative experiments aim to stimulate the development of theoretical models which can deal with the strong local particle interactions in this system.

  18. Real-time Measurement of Biomagnetic Vector Fields in Functional Syncytium Using Amorphous Metal

    NASA Astrophysics Data System (ADS)

    Nakayama, Shinsuke; Uchiyama, Tusyoshi

    2015-03-01

    Magnetic field detection of biological electric activities would provide a non-invasive and aseptic estimate of the functional state of cellular organization, namely a syncytium constructed with cell-to-cell electric coupling. In this study, we investigated the properties of biomagnetic waves which occur spontaneously in gut musculature as a typical functional syncytium, by applying an amorphous metal-based gradio-magneto sensor operated at ambient temperature without a magnetic shield. The performance of differentiation was improved by using a single amorphous wire with a pair of transducer coils. Biomagnetic waves of up to several nT were recorded ~1 mm below the sample in a real-time manner. Tetraethyl ammonium (TEA) facilitated magnetic waves reflected electric activity in smooth muscle. The direction of magnetic waves altered depending on the relative angle of the muscle layer and magneto sensor, indicating the existence of propagating intercellular currents. The magnitude of magnetic waves rapidly decreased to ~30% by the initial and subsequent 1 mm separations between sample and sensor. The large distance effect was attributed to the feature of bioelectric circuits constructed by two reverse currents separated by a small distance. This study provides a method for detecting characteristic features of biomagnetic fields arising from a syncytial current.

  19. Real-time Measurement of Biomagnetic Vector Fields in Functional Syncytium Using Amorphous Metal

    PubMed Central

    Nakayama, Shinsuke; Uchiyama, Tusyoshi

    2015-01-01

    Magnetic field detection of biological electric activities would provide a non-invasive and aseptic estimate of the functional state of cellular organization, namely a syncytium constructed with cell-to-cell electric coupling. In this study, we investigated the properties of biomagnetic waves which occur spontaneously in gut musculature as a typical functional syncytium, by applying an amorphous metal-based gradio-magneto sensor operated at ambient temperature without a magnetic shield. The performance of differentiation was improved by using a single amorphous wire with a pair of transducer coils. Biomagnetic waves of up to several nT were recorded ~1 mm below the sample in a real-time manner. Tetraethyl ammonium (TEA) facilitated magnetic waves reflected electric activity in smooth muscle. The direction of magnetic waves altered depending on the relative angle of the muscle layer and magneto sensor, indicating the existence of propagating intercellular currents. The magnitude of magnetic waves rapidly decreased to ~30% by the initial and subsequent 1 mm separations between sample and sensor. The large distance effect was attributed to the feature of bioelectric circuits constructed by two reverse currents separated by a small distance. This study provides a method for detecting characteristic features of biomagnetic fields arising from a syncytial current. PMID:25744476

  20. Self-referencing luminescent optrodes for non-invasive, real time measurement of extracellular flux

    NASA Astrophysics Data System (ADS)

    McLamore, Eric S.; Porterfield, D. Marshall; Borgens, R. B.; Banks, M. K.

    2011-05-01

    Autonomous technologies are needed which are capable of sensing real time changes in biophysical transport across cell membranes/organelles. These technologies must not only be highly sensitive/selective, but must also be minimally invasive/intrusive, causing no significant physical/chemical effects on cell behavior. Challenges with mainstream technologies (e.g., assays, fluorescent dyes, microsensors) include signal noise/drift, low temporal resolution, requirement of large sample sizes, cytoxicity, organelle sequestration, and intracellular buffering. Recent advancements in fiber optics have greatly enhanced the performance of microsensors (e.g., increased sensitivity/selectivity, response time), but used in concentration mode near cells/tissues these sensors suffer from poor signal to noise ratio. Work over the last few decades has advanced microsensor utility through sensing modalities that extend and enhance the data recorded by sensors. This technique, known as self-referencing, converts static micro/nanosensors with otherwise low signal-to-noise ratios into dynamic flux sensors capable of filtering out signals not associated with active transport by acquisition and amplification of differential signals. Here, we demonstrate the use of a self-referencing referencing frequency domain fiber optic microsensor containing a quenched dye (platinum tetrakis-pentafluorophenyl porphyrin) for quantifying cell/tissue flux in biomedical, agricultural, and environmental applications.

  1. Real-time Measurement of Mechanical Fluctuations in Carbon Nanotube Resonators

    NASA Astrophysics Data System (ADS)

    Tsioutsios, Ioannis; Tavernarakis, Alexandros; Osmond, Johann; Verlot, Pierre; Bachtold, Adrian

    Carbon nanotube resonators have been recently shown to hold an exceptional sensing potential, relying on their extremely low mass. As a consequence, they are also expected to transduce the fundamental thermal force into very large motion fluctuations. Recently, an increasing number of theoretical proposals have suggested that this property may strongly affect the vibrational behaviour of carbon nanotube resonators, which has so far remained unobserved. Here we report the first, real-time detection of the thermally-induced vibrations in carbon nanotube resonators with masses in the 10 ag range. We show that coupling singly-clamped carbon nanotubes to a focused electron beam enables the full access to their mechanical trajectories. Our detailed analysis demonstrates that our devices behave as linear harmonic oscillators undergoing thermally-driven Brownian motion. Our result establish the viability of carbon nanotube resonator technology at room temperature and paves the way towards the observing novel thermodynamics regimes in nanomechanics. ICFO, Institut de Ciències Fotòniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain.

  2. Real-time measurement of biomagnetic vector fields in functional syncytium using amorphous metal.

    PubMed

    Nakayama, Shinsuke; Uchiyama, Tusyoshi

    2015-01-01

    Magnetic field detection of biological electric activities would provide a non-invasive and aseptic estimate of the functional state of cellular organization, namely a syncytium constructed with cell-to-cell electric coupling. In this study, we investigated the properties of biomagnetic waves which occur spontaneously in gut musculature as a typical functional syncytium, by applying an amorphous metal-based gradio-magneto sensor operated at ambient temperature without a magnetic shield. The performance of differentiation was improved by using a single amorphous wire with a pair of transducer coils. Biomagnetic waves of up to several nT were recorded ~1 mm below the sample in a real-time manner. Tetraethyl ammonium (TEA) facilitated magnetic waves reflected electric activity in smooth muscle. The direction of magnetic waves altered depending on the relative angle of the muscle layer and magneto sensor, indicating the existence of propagating intercellular currents. The magnitude of magnetic waves rapidly decreased to ~30% by the initial and subsequent 1 mm separations between sample and sensor. The large distance effect was attributed to the feature of bioelectric circuits constructed by two reverse currents separated by a small distance. This study provides a method for detecting characteristic features of biomagnetic fields arising from a syncytial current. PMID:25744476

  3. Real-time detection and characterization of individual flowing airborne biological particles: fluorescence spectra and elastic scattering measurements

    NASA Astrophysics Data System (ADS)

    Pan, Yongle; Holler, Stephen; Chang, Richard K.; Hill, Steven C.; Pinnick, Ronald G.; Niles, Stanley; Bottiger, Jerold R.; Bronk, Burt V.

    1999-11-01

    Real-time methods which is reagentless and could detect and partially characterize bioaerosols are of current interest. We present a technique for real-time measurement of UV-excited fluorescence spectra and two-dimensional angular optical scattering (TAOS) from individual flowing biological aerosol particles. The fluorescence spectra have been observed from more than 20 samples including Bacillus subtilis, Escherichia coli, Erwinia herbicola, allergens, dust, and smoke. The S/N and resolution of the spectra are sufficient for observing small lineshape differences among the same type of bioaerosol prepared under different conditions. The additional information from TAOS regarding particle size, shape, and granularity has the potential of aiding in distinguishing bacterial aerosols from other aerosols, such as diesel and cigarette smoke.

  4. Development of a hybrid Raman spectroscopy and optical coherence tomography technique for real-time in vivo tissue measurements.

    PubMed

    Wang, Jianfeng; Zheng, Wei; Lin, Kan; Huang, Zhiwei

    2016-07-01

    We report on the development of a unique sideview handheld hybrid Raman spectroscopy (RS) and optical coherence tomography (OCT) technique for real-time in vivo tissue measurements. A sideview handheld RS-OCT optical probe is designed to coalign the optical paths of RS and OCT sampling arms, whereby a compact long-pass dichroic mirror (LPDM) is utilized to transmit the OCT signal through a gradient index rod lens and a reflection mirror, whereas the LPDM deflects the tissue Raman signal by 90°, leading to coaligned RS/OCT optical samplings on the tissue. Further study shows that the hybrid RS and OCT technique developed is capable of simultaneously acquiring both morphological and biochemical information about the oral tissue in vivo, facilitating real-time, in vivo tissue diagnoses and characterizations in the oral cavity. PMID:27367097

  5. Real-time cell analysis--a new method for dynamic, quantitative measurement of infectious viruses and antiserum neutralizing activity.

    PubMed

    Teng, Zheng; Kuang, Xiaozhou; Wang, Jiayu; Zhang, Xi

    2013-11-01

    A newly developed electronic cell sensor array--the xCELLigence real-time cell analysis (RTCA) system is tested currently for dynamic monitoring of cell attachment, proliferation, damage, and death. In this study, human enterovirus (HEV71) infection of human rhabdomyosarcoma (RD) was used as an in vitro model to validate the application of this novel system as a straightforward and efficient assay for quantitative measurement of infectious viruses based on virus-induced cytopathic effect (CPE). Several experimental tests were performed including the determination of optimal seeding density of the RD cells in 96-well E-plates, RTCA real-time monitoring of the virus induced CPE and virus titer calculation, and viral neutralization test to determine HEV71 antibody titer. Traditional 50% tissue culture infective dose (TCID50) assay was also conducted for methodology comparison and validation, which indicated a consistent result between the two assays. These findings indicate that the xCELLigence RTCA system can be a valuable addition to current viral assays for quantitative measurement of infectious viruses and quantitation of neutralization antibody titer in real-time, warranting for future research and exploration of applications to many other animal and human viruses. PMID:23835032

  6. Spatiotemporal Effects of Sonoporation Measured by Real-Time Calcium Imaging

    PubMed Central

    Kumon, R. E.; Aehle, M.; Sabens, D.; Parikh, P.; Han, Y. W.; Kourennyi, D.; Deng, C. X.

    2009-01-01

    To investigate the effects of sonoporation, spatiotemporal evolution of ultrasound-induced changes in intracellular calcium ion concentration ([Ca2+]i) was determined using real time fura-2AM fluorescence imaging. Monolayers of Chinese hamster ovary (CHO) cells were exposed to 1-MHz ultrasound tone burst (0.2 s, 0.45 MPa) in the presence of Optison™ microbubbles. At extracellular [Ca2+]o of 0.9 mM, ultrasound application generated both non-oscillating and oscillating (periods 12–30 s) transients (changes of [Ca2+]i in time) with durations of 100–180 s. Immediate [Ca2+]i transients after ultrasound application were induced by ultrasound-mediated microbubble–cell interactions. In some cases, the immediately-affected cells did not return to pre-ultrasound equilibrium [Ca2+]i levels, thereby indicating irreversible membrane damage. Spatial evolution of [Ca2+]i in different cells formed a calcium wave and was observed to propagate outward from the immediately-affected cells at 7–20 μm/s over a distance greater than 200 μm, causing delayed transients in cells to occur sometimes 60 s or more after ultrasound application. In calcium-free solution, ultrasound-affected cells did not recover, consistent with the requirement of extracellular Ca2+ for cell membrane recovery subsequent to sonoporation. In summary, ultrasound application in the presence of Optison™ microbubbles can generate transient [Ca2+]i changes and oscillations at a focal site and in surrounding cells via calcium waves that last longer than the ultrasound duration and spread beyond the focal site. These results demonstrate the complexity of downstream effects of sonoporation beyond the initial pore formation and subsequent diffusion-related transport through the cellular membrane. PMID:19010589

  7. Real-time intraocular pressure measurement during phacoemulsification in dogs ex vivo

    PubMed Central

    KANG, Seonmi; PARK, Sangwan; NOH, Hyunwoo; KWAK, Jiyoon; SEO, Kangmoon

    2015-01-01

    This study was performed to evaluate changes in intraocular pressure (IOP) during standard coaxial phacoemulsification using 4 different bottle heights (BHs) and 2 different incision sizes. Coaxial phacoemulsification was performed with a venturi-based machine in 8 enucleated canine eyes through 3.0 and 3.2 mm clear corneal incisions (CCIs). A pressure transducer inserted in the peripheral cornea monitored the IOP in real-time. The surgery was subdivided into 4 stages: sculpt-segment removal, irrigation/aspiration, capsular polishing and viscoelastic removal. The mean IOP and the difference between the maximum and minimum IOPs were calculated at each stage and compared. The ultrasound time and volume of irrigation fluid used were recorded. The mean IOP increased with an elevation in the BH. The mean IOP in the irrigation/aspiration stage was significantly higher than that in the sculpt-segment removal stage at the same BH. The difference between the maximum and minimum IOP at each stage was greater in the 3.2 mm than the 3.0 mm CCIs, although the mean IOP was lower with the 3.2 mm than the 3.0 mm CCIs. The ultrasound time and irrigation fluid volume were greater with the 3.2 mm than the 3.0 mm CCIs. Therefore, fluidic parameters during each stage could be reassessed and adjusted to reduce complications arising from an elevated IOP. Phacoemulsification with 3.0 mm CCIs at a lower BH might lead to less stress on the eye from IOP fluctuations, ultrasound energy and irrigation fluid. PMID:25716691

  8. A rapid and accurate quantification method for real-time dynamic analysis of cellular lipids during microalgal fermentation processes in Chlorella protothecoides with low field nuclear magnetic resonance.

    PubMed

    Wang, Tao; Liu, Tingting; Wang, Zejian; Tian, Xiwei; Yang, Yi; Guo, Meijin; Chu, Ju; Zhuang, Yingping

    2016-05-01

    The rapid and real-time lipid determination can provide valuable information on process regulation and optimization in the algal lipid mass production. In this study, a rapid, accurate and precise quantification method of in vivo cellular lipids of Chlorella protothecoides using low field nuclear magnetic resonance (LF-NMR) was newly developed. LF-NMR was extremely sensitive to the algal lipids with the limits of the detection (LOD) of 0.0026g and 0.32g/L in dry lipid samples and algal broth, respectively, as well as limits of quantification (LOQ) of 0.0093g and 1.18g/L. Moreover, the LF-NMR signal was specifically proportional to the cellular lipids of C. protothecoides, thus the superior regression curves existing in a wide detection range from 0.02 to 0.42g for dry lipids and from 1.12 to 8.97gL(-1) of lipid concentration for in vivo lipid quantification were obtained with all R(2) higher than 0.99, irrespective of the lipid content and fatty acids profile variations. The accuracy of this novel method was further verified to be reliable by comparing lipid quantification results to those obtained by GC-MS. And the relative standard deviation (RSD) of LF-NMR results were smaller than 2%, suggesting the precision of this method. Finally, this method was successfully used in the on-line lipid monitoring during the algal lipid fermentation processes, making it possible for better understanding of the lipid accumulation mechanism and dynamic bioprocess control. PMID:26948045

  9. Model- based filtering for artifact and noise suppression with state estimation for electrodermal activity measurements in real time.

    PubMed

    Tronstad, Christian; Staal, Odd M; Saelid, Steinar; Martinsen, Orjan G

    2015-08-01

    Measurement of electrodermal activity (EDA) has recently made a transition from the laboratory into daily life with the emergence of wearable devices. Movement and nongelled electrodes make these devices more susceptible to noise and artifacts. In addition, real-time interpretation of the measurement is needed for user feedback. The Kalman filter approach may conveniently deal with both these issues. This paper presents a biophysical model for EDA implemented in an extended Kalman filter. Employing the filter on data from Physionet along with simulated noise and artifacts demonstrates noise and artifact suppression while implicitly providing estimates of model states and parameters such as the sudomotor nerve activation. PMID:26736861

  10. In-Situ, Real-Time Measurement of Melt Constituents in the Aluminum, Glass, and Steel Industries

    SciTech Connect

    Robert De Saro

    2006-05-18

    Energy Research Company (ERCo), with support from DOE’s Industrial Technologies Program, Sensors and Automation has developed a Laser Induced Breakdown Spectroscopy (LIBS) probe to measure, in real time and in-situ, the composition of an aluminum melt in a furnace at an industrial plant. The compositional data is provided to the operator continuously allowing the operator to adjust the melt composition, saving energy, increasing production, and maintaining tighter compositional tolerances than has been previously possible. The overall objectives of this project were to: -- design, develop, fabricate, test and project future costs of the LIBS probe on bench-size experiments; - test the unit in a pilot-scaled aluminum furnace under varying operating conditions of temperature and melt constituents; -- determine the instruments needed for use in industrial environment; -- compare LIBS Probe data to readings traditionally taken on the furnace; -- get full-scale data to resolve if, and how, the LIBS Probe design should be modified for operator acceptance. Extensive laboratory tests have proven the concept feasibility. Elemental concentrations below 0.1% wt. have been accurately measured. Further, the LIBS system has now been installed and is operating at a Commonwealth Aluminum plant in Ohio. The technology is crosscutting as it can be used in a wide variety of applications. In the Sensors and Automation Program the application was for the secondary aluminum industry. However, this project spawned a number of other applications, which are also reported here for completeness. The project was effective in that two commercial systems are now operating; one at Commonwealth Aluminum and another at a PPG fiberglass plant. Other commercial installations are being negotiated as of this writing. This project led to the following conclusions: 1. The LIBS System has been developed for industrial applications. This is the first time this has been accomplished. In addition, two

  11. Real-time measurement of UV-inactivated Escherichia coli bacterial particles by electrospray-assisted UVAPS spectrometry.

    PubMed

    Jung, Jae Hee; Lee, Jung Eun; Bae, Gwi Nam

    2011-08-01

    The ultraviolet aerodynamic particle sizer (UVAPS) is a novel commercially available aerosol spectrometer for real-time continuous monitoring of viable bioaerosols, based on fluorescence from living microorganisms. In a previous study, we developed an electrospray-assisted UVAPS using biological electrospray techniques, which have the advantage of generating non-agglomerated single particles by the repulsive electrical forces. With this electrospraying of suspensions containing microorganisms, the analytical system can supply more accurate and quantitative information about living microorganisms than with conventional aerosolization. Using electrospray-assisted UVAPS, we investigated the characteristics of bacterial particles with various viabilities in real-time. Escherichia coli was used as the test microorganism, and its initial viability was controlled by the degree of exposure to UV irradiation. In the stable cone-jet domain, the particle size distributions of test bacterial particles remained almost uniform regardless of the degree of UV inactivation. However, the fluorescence spectra of the bacterial particles changed with the degree of UV inactivation. The fluorescence characteristics of UV-inactivated bacterial particles tended to show a similar decline with viability, determined by the sampling and culture method, although the percentage showing fluorescence was higher than that showing viability. PMID:21621246

  12. Real-time measuring system design and application of thermal expansion displacement during resistance spot welding process

    NASA Astrophysics Data System (ADS)

    Li, YongBing; Xu, Jun; Chen, GuanLong; Lin, ZhongQin

    2005-12-01

    Resistance spot welding (RSW) technology is the most important joining method in auto-body manufacturing. Quality of spot weld not only determines reliability and safety of cars, but also has an important influence on assembly variation of auto-body. Many welding quality parameters, such as welding current, electric resistance, electrode pressure, and thermal expansion displacement, had been proposed to monitoring and controlling spot weld quality, in which thermal expansion displacement was thought as a very promising method. But the measurement of dynamic displacement encounters many difficulties in measuring precision, measuring speed and sensor installation, which limit the usage of this method. This paper introduced a kind of laser displacement sensor made in OMRON to overcome the limitations of displacement measuring precision and measuring speed, and at the same time designed an ingenious fixture to mount the sensor to welding gun. Calibration experiments showed that the fixture reduced vibration introduced by pneumatic welding gun and interference between sensor and welding gun, and have a good linearity with standard clearance gauge. Based on this measuring system, dynamic thermal expansion displacement during RSW process was real-time monitored. Analysis found thermal expansion displacement can be used to real-time distinguish weld quality, such as small nugget, splash.

  13. Ambient measurements of biological aerosol particles near Killarney, Ireland: a comparison between real-time fluorescence and microscopy techniques

    NASA Astrophysics Data System (ADS)

    Healy, D. A.; Huffman, J. A.; O'Connor, D. J.; Pöhlker, C.; Pöschl, U.; Sodeau, J. R.

    2014-08-01

    Primary biological aerosol particles (PBAPs) can contribute significantly to the coarse particle burden in many environments. PBAPs can thus influence climate and precipitation systems as cloud nuclei and can spread disease to humans, animals, and plants. Measurement data and techniques for PBAPs in natural environments at high time- and size resolution are, however, sparse, and so large uncertainties remain in the role that biological particles play in the Earth system. In this study two commercial real-time fluorescence particle sensors and a Sporewatch single-stage particle impactor were operated continuously from 2 August to 2 September 2010 at a rural sampling location in Killarney National Park in southwestern Ireland. A cascade impactor was operated periodically to collect size-resolved particles during exemplary periods. Here we report the first ambient comparison of a waveband integrated bioaerosol sensor (WIBS-4) with a ultraviolet aerodynamic particle sizer (UV-APS) and also compare these real-time fluorescence techniques with results of fluorescence and optical microscopy of impacted samples. Both real-time instruments showed qualitatively similar behavior, with increased fluorescent bioparticle concentrations at night, when relative humidity was highest and temperature was lowest. The fluorescent particle number from the FL3 channel of the WIBS-4 and from the UV-APS were strongly correlated and dominated by a 3 μm mode in the particle size distribution. The WIBS FL2 channel exhibited particle modes at approx. 1 and 3 μm, and each was correlated with the concentration of fungal spores commonly observed in air samples collected at the site (ascospores, basidiospores, Ganoderma spp.). The WIBS FL1 channel exhibited variable multimodal distributions turning into a broad featureless single mode after averaging, and exhibited poor correlation with fungal spore concentrations, which may be due to the detection of bacterial and non-biological fluorescent

  14. Ambient measurements of biological aerosol particles near Killarney, Ireland: a comparison between real-time fluorescence and microscopy techniques

    NASA Astrophysics Data System (ADS)

    Healy, D. A.; Huffman, J. A.; O'Connor, D. J.; Pöhlker, C.; Pöschl, U.; Sodeau, J. R.

    2014-02-01

    Primary biological aerosol particles (PBAP) can contribute significantly to the coarse particle burden in many environments, may thus influence climate and precipitation systems as cloud nuclei, and can spread disease to humans, animals, and plants. Measurements of PBAP in natural environments taken at high time- and size- resolution are, however, sparse and so large uncertainties remain in the role that biological particles play in the Earth system. In this study two commercial real-time fluorescence particle sensors and a Sporewatch single-stage particle impactor were operated continuously from 2 August to 2 September 2010 at a rural sampling location in Killarney National Park in south western Ireland. A cascade impactor was operated periodically to collect size-resolved particles during exemplary periods. Here we report the first ambient comparison of the waveband integrated bioaerosol sensor (WIBS-4) with the ultraviolet aerodynamic particle sizer (UV-APS) and also compare these real-time fluorescence techniques with results of fluorescence and optical microscopy of impacted samples. Both real-time instruments showed qualitatively similar behaviour, with increased fluorescent bioparticle concentrations at night when relative humidity was highest and temperature was lowest. The fluorescent particle number from the FL3 channel of the WIBS-4 and from the UV-APS were strongly correlated and dominated by a 3 μm mode in the particle size distribution. The WIBS FL2 channel exhibited particle modes at approx. 1 and 3 μm, and each were correlated with the concentration of fungal spores commonly observed in air samples collected at the site (ascospores, basidiospores, Ganoderma spp.). The WIBS FL1 channel exhibited variable multi-modal distributions turning into a broad featureless single mode after averaging and exhibited poor correlation with fungal spore concentrations, which may be due to the detection of bacterial and non-biological fluorescent particles

  15. Implementation of a data processing platform for real-time distance measurement with dual-comb lasers

    NASA Astrophysics Data System (ADS)

    Ni, Kai; Xu, Mingfei; Zhou, Qian; Dong, Hao; Li, Xinghui; Wu, Guanhao

    2015-08-01

    Absolute distance measurement with dual femtosecond comb lasers has advantages of wide-range, high-accuracy and fast speed. It combines time-of-flight and interferometric measurement. The novelty of ranging method leads to new challenges in designing the data acquisition and processing hardware system. Currently there are no available real-time data processing system for dual-comb ranging. This paper introduces our recent progress on designing and implementing such a platform. Our platform mainly contains four different function modules. First, a clock module that accept a 250MHz maximum reference clock input was introduced to generate the sample clock for A/D converter, and the module's output clock can be delayed up to 20ns with a resolution of 714ps. Second, a high-speed data acquisition module with a 14-bit resolution and a 125 MSPS maximum sample rate was designed to convert the analog laser pulse signal to digital signal. Third, we built a real-time data processing module that allows an input of 16-bit data in the FPGA to calculate the distance from the digital signal within 83us. Finally, a data transmission module based on a 128MB DDR SDRAM and USB2.0 was added so that we can easily debug the platform in the PC. The performance of our system is evaluated in real-time. The test bench consists of two femtosecond laser sources, an optical fiber interferometer and our data processing system. The repetition frequencies of the two combs are around 50MHz, with frequency difference of 2.5kHz. The center wavelength of laser pulses is 1560nm. The target distance is from 0m to 3m. The experimental results show that our system can output measurement results at the rate of 2500 pts/s, and the measurement deviation is less than 10um.

  16. Real-time cell analysis: sensitivity of different vertebrate cell cultures to copper sulfate measured by xCELLigence(®).

    PubMed

    Rakers, S; Imse, F; Gebert, M

    2014-10-01

    In this study, we report the use of a real-time cell analysis (RTCA) test system, the xCELLigence(®) RTCA, as efficient tool for a fast cytotoxicity analysis and comparison of four different vertebrate cell cultures. This new dynamic real-time monitoring and impedance-based assay allows for a combined measurement of cell adhesion, spreading and proliferation. Cell cultures were obtained from mouse, rat, human and fish, all displaying a fibroblast-like phenotype. The measured impedance values could be correlated to characteristic cell culture behaviours. In parallel, relative cytotoxicity of a commonly used but due to its very good water solubility highly hazardous pesticide, copper sulfate, was evaluated under in vitro conditions through measurements of cell viability by classical end-point based assays MTT and PrestoBlue(®). Cell line responses in terms of viability as measured by these three methods were variable between the fish skin cells and cells from higher vertebrates and also between the three methods. The advantage of impedance-based measurements is mainly based on the continuous monitoring of cell responses for a broad range of different cells, including fish cells. PMID:25001081

  17. Fast and Accurate Exhaled Breath Ammonia Measurement

    PubMed Central

    Solga, Steven F.; Mudalel, Matthew L.; Spacek, Lisa A.; Risby, Terence H.

    2014-01-01

    This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations. PMID:24962141

  18. Spatial filtering velocimetry for real-time measurements of speckle dynamics due to out-of-plane motion.

    PubMed

    Olesen, Anders Sig; Jakobsen, Michael Linde

    2016-05-10

    This paper describes an optical spatial filtering velocimetry technique that converts an expanding or contracting speckle pattern into a photocurrent. This photocurrent will have a quasi-sinusoidal dependency on this specific speckle motion. The spatial filter consists of a series of concentric rings. Each ring divides the incoming light into two radial-wise, almost even contributions and directs them by refraction toward two half-rings of photodetectors. The corresponding two photocurrents are balanced and provide a differential photocurrent. In this paper the optical spatial filtering velocimetry technique is used to demonstrate real-time measurements of speckle dynamics due to out-of-plane motion. PMID:27168304

  19. Flow Cytometry for Real-Time Measurement of Guanine Nucleotide Binding and Exchange by Ras-like GTPases

    PubMed Central

    Schwartz, Samantha L.; Tessema, Mathewos; Buranda, Tione; Phlypenko, Olena; Rak, Alexey; Simons, Peter C.; Surviladze, Zurab; Sklar, Larry A.; Wandinger-Ness, Angela

    2008-01-01

    Ras-like small GTPases cycle between GTP-bound active and GDP-bound inactive conformational states to regulate diverse cellular processes. Despite their importance, detailed kinetic or comparative studies of family members are rarely undertaken due to the lack of real-time assays measuring nucleotide binding or exchange. Here, we report a bead-based, flow cytometric assay that quantitatively measures the nucleotide binding properties of GST-chimeras for prototypical Ras-family members Rab7 and Rho. Measurements are possible in the presence or absence of Mg2+, with magnesium cations principally increasing affinity and slowing nucleotide dissociation rate 8- to 10-fold. GST-Rab7 exhibited a 3-fold higher affinity for GDP relative to GTP that is consistent with a 3-fold slower dissociation rate of GDP. Strikingly, GST-Rab7 had a marked preference for GTP with ribose ring-conjugated BODIPY FL. The more commonly used γ-NH-conjugated BODIPY FL GTP analogue failed to bind to GST-Rab7. In contrast, both BODIPY analogues bound equally well to GST-RhoA and GST-RhoC. Comparisons of the GST-Rab7 and GST-RhoA GTP-binding pockets provide a structural basis for the observed binding differences. In sum, the flow cytometric assay can be used to measure nucleotide binding properties of GTPases in real-time and quantitatively assess differences between GTPases. PMID:18638444

  20. Development and validation of a low-cost infrared measurement system for real-time monitoring of indoor thermal comfort

    NASA Astrophysics Data System (ADS)

    Revel, G. M.; Arnesano, M.; Pietroni, F.

    2014-08-01

    A low-cost infrared measurement system has been developed to monitor in real time thermal comfort conditions in indoor environments. The device employs a scanning linear array of thermopiles installed on the ceiling of the room and is assessed and controlled by an embedded microcontroller to measure indoor surface temperatures. This feature allows the evaluation of the mean radiant temperature (Tr), in compliance with ISO 7726, for several positions inside the space. Together with Tr, the variables required by ISO 7730 are measured to calculate the predicted mean vote (PMV). The PMV and Tr are provided as real-time outputs of the device through a wireless or wired connection, also as distribution maps. The paper reports a detailed description of the system, its calibration and uncertainty analysis. The capability of predicting thermal comfort conditions for multiple positions in the room has been tested and validated in a real case study with respect to a reference measurement system (microclimate station). Comparison showed a deviation of ±0.5 °C for Tr and ±0.1 for PMV without direct solar radiation and an average deviation of ±2.0 °C for Tr and ±0.2 for PMV with direct solar radiation.

  1. Handheld directional reflectometer: an angular imaging device to measure BRDF and HDR in real time

    NASA Astrophysics Data System (ADS)

    Mattison, Phillip R.; Dombrowski, Mark S.; Lorenz, James M.; Davis, Keith J.; Mann, Harley C.; Johnson, Philip; Foos, Bryan

    1998-10-01

    Many applications require quantitative measurements of surface light scattering, including quality control on production lines, inspection of painted surfaces, inspection of field repairs, etc. Instruments for measuring surface scattering typically fall into two main categories, namely bidirectional reflectometers, which measure the angular distribution of scattering, and hemispherical directional reflectometers, which measure the total scattering into the hemisphere above the surface. Measurement of the bi-directional reflectance distribution function (BRDF) gives the greatest insight into how light is scattered from a surface. Measurements of BRDF, however, are typically very lengthy measurements taken by moving a source and detector to map the scattering. Since BRDF has four angular degrees of freedom, such measurements can require hours to days to complete. Instruments for measuring BRDF are also typically laboratory devices, although a field- portable bi-directional reflectometer does exist. Hemispherical directional reflectance (HDR) is a much easier measurement to make, although care must be taken to use the proper methodology when measuring at wavelengths beyond 10 micrometer, since integrating spheres (typically used to make such measurements) are very energy inefficient and lose their integrating properties at very long wavelengths. A few field- portable hemispherical directional reflectometers do exist, but typically measure HDR only at near-normal angles. Boeing Defense and Space Group and Surface Optics Corporation, under a contract from the Air Force Research Laboratory, have developed a new hand-held instrument capable of measuring both BRDF and HDR using a unique, patented angular imaging technique. A combination of an hemi-ellipsoidal mirror and an additional lens translate the angular scatter from a surface into a two-dimensional spatial distribution, which is recorded by an imaging array. This configuration fully maps the scattering from a half

  2. Real Time Measurement of the Size Distribution of Particulate Matter by a Light Scattering Method

    ERIC Educational Resources Information Center

    Gravatt, C. C., Jr.

    1973-01-01

    Discusses a light scattering instrument designed to measure the size of particles in an air flow in approximately 25 microseconds and at a concentration as high as 10,000 particles/cc. Indicates that the measurement can be made for all particles, independent of their index of refraction. (CC)

  3. A real-time measurement system for parameters of live biology metabolism process with fiber optics

    NASA Astrophysics Data System (ADS)

    Tao, Wei; Zhao, Hui; Liu, Zemin; Cheng, Jinke; Cai, Rong

    2010-08-01

    Energy metabolism is one of the basic life activities of cellular in which lactate, O2 and CO2 will be released into the extracellular environment. By monitoring the quantity of these parameters, the mitochondrial performance will be got. A continuous measurement system for the concentration of O2, CO2 and PH value is introduced in this paper. The system is made up of several small-sized fiber optics biosensors corresponding to the container. The setup of the system and the principle of measurement of several parameters are explained. The setup of the fiber PH sensor based on principle of light absorption is also introduced in detail and some experimental results are given. From the results we can see that the system can measure the PH value precisely suitable for cell cultivation. The linear and repeatable accuracies are 3.6% and 6.7% respectively, which can fulfill the measurement task.

  4. Uncertainty modelling of real-time observation of a moving object: photogrammetric measurements

    NASA Astrophysics Data System (ADS)

    Ulrich, Thomas

    2015-04-01

    Photogrametric systems are widely used in the field of industrial metrology to measure kinematic tasks such as tracking robot movements. In order to assess spatiotemporal deviations of a kinematic movement, it is crucial to have a reliable uncertainty of the kinematic measurements. Common methods to evaluate the uncertainty in kinematic measurements include approximations specified by the manufactures, various analytical adjustment methods and Kalman filters. Here a hybrid system estimator in conjunction with a kinematic measurement model is applied. This method can be applied to processes which include various types of kinematic behaviour, constant velocity, variable acceleration or variable turn rates. Additionally, it has been shown that the approach is in accordance with GUM (Guide to the Expression of Uncertainty in Measurement). The approach is compared to the Kalman filter using simulated data to achieve an overall error calculation. Furthermore, the new approach is used for the analysis of a rotating system as this system has both a constant and a variable turn rate. As the new approach reduces overshoots it is more appropriate for analysing kinematic processes than the Kalman filter. In comparison with the manufacturer’s approximations, the new approach takes account of kinematic behaviour, with an improved description of the real measurement process. Therefore, this approach is well-suited to the analysis of kinematic processes with unknown changes in kinematic behaviour.

  5. Real-time optical pH measurement in a standard microfluidic cell culture system.

    PubMed

    Magnusson, Einar B; Halldorsson, Skarphedinn; Fleming, Ronan M T; Leosson, Kristjan

    2013-01-01

    The rapid growth of microfluidic cell culturing in biological and biomedical research and industry calls for fast, non-invasive and reliable methods of evaluating conditions such as pH inside a microfluidic system. We show that by careful calibration it is possible to measure pH within microfluidic chambers with high accuracy and precision, using a direct single-pass measurement of light absorption in a commercially available phenol-red-containing cell culture medium. The measurement is carried out using a standard laboratory microscope and, contrary to previously reported methods, requires no modification of the microfluidic device design. We demonstrate the validity of this method by measuring absorption of light transmitted through 30-micrometer thick microfluidic chambers, using an inverted microscope fitted with a scientific-grade digital camera and two bandpass filters. In the pH range of 7-8, our measurements have a standard deviation and absolute error below 0.05 for a measurement volume smaller than 4 nL. PMID:24049695

  6. Real-time Redox Measurements during Endoplasmic Reticulum Stress Reveal Interlinked Protein Folding Functions

    PubMed Central

    Merksamer, Philip I.; Trusina, Ala; Papa, Feroz R.

    2008-01-01

    SUMMARY Disruption of protein folding in the endoplasmic reticulum (ER) causes unfolded proteins to accumulate, triggering the unfolded protein response (UPR). UPR outputs in turn decrease ER unfolded proteins to close a negative feedback loop. However, because it is infeasible to directly measure the concentration of unfolded proteins in vivo, cells are generically described as experiencing “ER stress” whenever the UPR is active. Because ER redox potential is optimized for oxidative protein folding, we reasoned that measureable redox changes should accompany unfolded protein accumulation. To test this concept, we employed fluorescent protein reporters to dynamically measure ER redox status and UPR activity in single cells. Using these tools, we show that diverse stressors, both experimental and physiological, compromise ER protein oxidation when UPR-imposed homeostatic control is lost. Using genetic analysis we uncovered redox heterogeneities in isogenic cell populations, and revealed functional interlinks between ER protein folding, modification, and quality control systems. PMID:19026441

  7. MTF measurements on real time for performance analysis of electro-optical systems

    NASA Astrophysics Data System (ADS)

    Stuchi, Jose Augusto; Signoreto Barbarini, Elisa; Vieira, Flavio Pascoal; dos Santos, Daniel, Jr.; Stefani, Mário Antonio; Yasuoka, Fatima Maria Mitsue; Castro Neto, Jarbas C.; Linhari Rodrigues, Evandro Luis

    2012-06-01

    The need of methods and tools that assist in determining the performance of optical systems is actually increasing. One of the most used methods to perform analysis of optical systems is to measure the Modulation Transfer Function (MTF). The MTF represents a direct and quantitative verification of the image quality. This paper presents the implementation of the software, in order to calculate the MTF of electro-optical systems. The software was used for calculating the MTF of Digital Fundus Camera, Thermal Imager and Ophthalmologic Surgery Microscope. The MTF information aids the analysis of alignment and measurement of optical quality, and also defines the limit resolution of optical systems. The results obtained with the Fundus Camera and Thermal Imager was compared with the theoretical values. For the Microscope, the results were compared with MTF measured of Microscope Zeiss model, which is the quality standard of ophthalmological microscope.

  8. Real-time measurement of alveolar size and population using phase contrast x-ray imaging

    PubMed Central

    Leong, Andrew F.T.; Buckley, Genevieve A.; Paganin, David M.; Hooper, Stuart B.; Wallace, Megan J.; Kitchen, Marcus J.

    2014-01-01

    Herein a propagation-based phase contrast x-ray imaging technique for measuring particle size and number is presented. This is achieved with an algorithm that utilizes the Fourier space signature of the speckle pattern associated with the images of particles. We validate this algorithm using soda-lime glass particles, demonstrating its effectiveness on random and non-randomly packed particles. This technique is then applied to characterise lung alveoli, which are difficult to measure dynamically in vivo with current imaging modalities due to inadequate temporal resolution and/or depth of penetration and field-of-view. We obtain an important result in that our algorithm is able to measure changes in alveolar size on the micron scale during ventilation and shows the presence of alveolar recruitment/de-recruitment in newborn rabbit kittens. This technique will be useful for ventilation management and lung diagnostic procedures. PMID:25426328

  9. Real-time measurement of alveolar size and population using phase contrast x-ray imaging.

    PubMed

    Leong, Andrew F T; Buckley, Genevieve A; Paganin, David M; Hooper, Stuart B; Wallace, Megan J; Kitchen, Marcus J

    2014-11-01

    Herein a propagation-based phase contrast x-ray imaging technique for measuring particle size and number is presented. This is achieved with an algorithm that utilizes the Fourier space signature of the speckle pattern associated with the images of particles. We validate this algorithm using soda-lime glass particles, demonstrating its effectiveness on random and non-randomly packed particles. This technique is then applied to characterise lung alveoli, which are difficult to measure dynamically in vivo with current imaging modalities due to inadequate temporal resolution and/or depth of penetration and field-of-view. We obtain an important result in that our algorithm is able to measure changes in alveolar size on the micron scale during ventilation and shows the presence of alveolar recruitment/de-recruitment in newborn rabbit kittens. This technique will be useful for ventilation management and lung diagnostic procedures. PMID:25426328

  10. Integrated formation evaluation data base combining MWD and real-time surface measurements with conventional logging data

    SciTech Connect

    Whittaker, A.; Dowsett, R.; Nigh, E.; Brooks, A.; MacPherson, J.

    1986-05-01

    Formation evaluation has traditionally involved collecting information density over protracted time periods from drilling data, mud logging, intermediate logs, cores, final logs, drill-stem tests, and other reports. After drilling was completed, information was still not complete. Log and core analyses and geochemical and paleontological evaluations required weeks or even months to be added to the data record. Thus, formation evaluation was rarely timely enough to influence exploration drilling decisions. With measurements while drilling (MWD), a new source of quantitative data became available during the drilling process. Recently, several new sensors have been added to MWD systems, and traditional mud logging methods have been enhanced to provide correlative data sources and benchmark standards for the lithologic normalization of MWD data. These data can be integrated within a single well-site data base to provide effective formation evaluation while the drilling process continues. The data base may be so structured that later available data, such as wireline logs, can be input to confirm and refine real-time evaluations. Similarly, the data base may be primed with geophysical and geological prognoses prior to drilling. Several case histories show the effective real-time determination of true total and effective porosities, fluid saturations, and estimates of formation characteristics such as mineralogy and permeability. In each case, later wireline logs and/or fluid recovery results confirmed the real-time evaluation. Where departures between early and late data sets occur, the data variations result from changes in downhole conditions and can be used to enhance formation evaluation by adding a dynamic component.

  11. Design and Development of a Real-Time Model Attitude Measurement System for Hypersonic Facilities

    NASA Technical Reports Server (NTRS)

    Jones, Thomas W.; Lunsford, Charles B.

    2005-01-01

    A series of wind tunnel tests have been conducted to evaluate a multi-camera videogrammetric system designed to measure model attitude in hypersonic facilities. The technique utilizes processed video data and applies photogrammetric principles for point tracking to compute model position including pitch, roll and yaw variables. A discussion of the constraints encountered during the design, development, and testing process, including lighting, vibration, operational range and optical access is included. Initial measurement results from the NASA Langley Research Center (LaRC) 31-Inch Mach 10 tunnel are presented.

  12. Design and Development of a Real-Time Model Attitude Measurement System for Hypersonic Facilities

    NASA Technical Reports Server (NTRS)

    Jones, Thomas W.; Lunsford, Charles B.

    2004-01-01

    A series of wind tunnel tests have been conducted to evaluate a multi-camera videogrammetric system designed to measure model attitude in hypersonic facilities. The technique utilizes processed video data and applies photogrammetric principles for point tracking to compute model position including pitch, roll and yaw variables. A discussion of the constraints encountered during the design, development, and testing process, including lighting, vibration, operational range and optical access is included. Initial measurement results from the NASA Langley Research Center (LaRC) 31-Inch Mach 10 tunnel are presented.

  13. Comparison of different real time VOC measurement techniques in a ponderosa pine forest

    NASA Astrophysics Data System (ADS)

    Kaser, L.; Karl, T.; Schnitzhofer, R.; Graus, M.; Herdlinger-Blatt, I. S.; DiGangi, J. P.; Sive, B.; Turnipseed, A.; Hornbrook, R. S.; Zheng, W.; Flocke, F. M.; Guenther, A.; Keutsch, F. N.; Apel, E.; Hansel, A.

    2012-10-01

    Volatile organic compound (VOC) mixing ratios measured by five independent instruments are compared at a forested site dominated by ponderosa pine (Pinus Ponderosa) during the BEACHON-ROCS field study in summer 2010. The instruments included a Proton Transfer Reaction Time of Flight Mass Spectrometer (PTR-TOF-MS), a Proton Transfer Reaction Quadrupole Mass Spectrometer (PTR-MS), a Fast Online Gas-Chromatograph coupled to a Mass Spectrometer (GC/MS; TOGA), a Thermal Dissociation Chemical Ionization Mass Spectrometer (PAN-CIMS) and a Fiber Laser-Induced Fluorescence Instrument (FILIF). The species discussed in this comparison include the most important biogenic VOCs and a selected suite of oxygenated VOCs that are thought to dominate the VOC reactivity at this particular site as well as typical anthropogenic VOCs that showed low mixing ratios at this site. Good agreement was observed for methanol, the sum of the oxygenated hemiterpene 2-methyl-3-buten-2-ol (MBO) and the hemiterpene isoprene, acetaldehyde, the sum of acetone and propanal, benzene and the sum of methyl ethyl ketone (MEK) and butanal. Measurements of the above VOCs conducted by different instruments agree within 20%. The ability to differentiate the presence of toluene and cymene by PTR-TOF-MS is tested based on a comparison with GC-MS measurements, suggesting a study-average relative contribution of 74% for toluene and 26% for cymene. Similarly, 2-hydroxy-2-methylpropanal (HMPR) is found to interfere with the sum of methyl vinyl ketone and methacrolein (MVK+MAC) using PTR-(TOF)-MS at this site. A study-average relative contribution of 85% for MVK+MAC and 15% for HMPR was determined. The sum of monoterpenes measured by PTR-MS and PTR-TOF-MS was generally 20-25% higher than the sum of speciated monoterpenes measured by TOGA, which included α-pinene, β-pinene, camphene, carene, myrcene, limonene, cineole as well as other terpenes. However, this difference is consistent throughout the study, and likely

  14. Comparison of different real time VOC measurement techniques in a ponderosa pine forest

    NASA Astrophysics Data System (ADS)

    Kaser, L.; Karl, T.; Schnitzhofer, R.; Graus, M.; Herdlinger-Blatt, I. S.; DiGangi, J. P.; Sive, B.; Turnipseed, A.; Hornbrook, R. S.; Zheng, W.; Flocke, F. M.; Guenther, A.; Keutsch, F. N.; Apel, E.; Hansel, A.

    2013-03-01

    Volatile organic compound (VOC) mixing ratios measured by five independent instruments are compared at a forested site dominated by ponderosa pine (Pinus Ponderosa) during the BEACHON-ROCS field study in summer 2010. The instruments included a Proton Transfer Reaction Time of Flight Mass Spectrometer (PTR-TOF-MS), a Proton Transfer Reaction Quadrupole Mass Spectrometer (PTR-MS), a Fast Online Gas-Chromatograph coupled to a Mass Spectrometer (GC/MS; TOGA), a Thermal Dissociation Chemical Ionization Mass Spectrometer (PAN-CIMS) and a Fiber Laser-Induced Fluorescence Instrument (FILIF). The species discussed in this comparison include the most important biogenic VOCs and a selected suite of oxygenated VOCs that are thought to dominate the VOC reactivity at this particular site as well as typical anthropogenic VOCs that showed low mixing ratios at this site. Good agreement was observed for methanol, the sum of the oxygenated hemiterpene 2-methyl-3-buten-2-ol (MBO) and the hemiterpene isoprene, acetaldehyde, the sum of acetone and propanal, benzene and the sum of methyl ethyl ketone (MEK) and butanal. Measurements of the above VOCs conducted by different instruments agree within 20%. The ability to differentiate the presence of toluene and cymene by PTR-TOF-MS is tested based on a comparison with GC-MS measurements, suggesting a study-average relative contribution of 74% for toluene and 26% for cymene. Similarly, 2-hydroxy-2-methylpropanal (HMPR) is found to interfere with the sum of methyl vinyl ketone and methacrolein (MVK + MAC) using PTR-(TOF)-MS at this site. A study-average relative contribution of 85% for MVK + MAC and 15% for HMPR was determined. The sum of monoterpenes measured by PTR-MS and PTR-TOF-MS was generally 20-25% higher than the sum of speciated monoterpenes measured by TOGA, which included α-pinene, β-pinene, camphene, carene, myrcene, limonene, cineole as well as other terpenes. However, this difference is consistent throughout the study, and

  15. Real-Time Temperature Measurement in a Vacuum Degasser Using Optical Pyrometry

    SciTech Connect

    Michel Bonin - Process Metrix; Peter Hues - Process Metrix; William Federoff - US Steel Nichloas Rymarchyk - Berry Metals; Todd Smith - Berry Metals

    2007-02-14

    The objective of the research was the development of a fiber-coupled, optical pyrometer for continuous temperature measurement in a vacuum degasser that reduces process time, enhances process control, and eliminates manual or robot-operated thermocouples. Through the live testing performed at US Steel's Edgar Thompson Works, the challenges associated with making optical temperature measurements in a vacuum chamber were identified. As a result of these challenges it was determined that continuous temperature monitoring in RH-type degassers was not a viable alternative to standard immersion thermocouples. The project was not successful.

  16. Ultrasonic device for real-time sewage velocity and suspended particles concentration measurements.

    PubMed

    Abda, F; Azbaid, A; Ensminger, D; Fischer, S; François, P; Schmitt, P; Pallarès, A

    2009-01-01

    In the frame of a technological research and innovation network in water and environment technologies (RITEAU, Réseau de Recherche et d'Innovation Technologique Eau et Environnement), our research group, in collaboration with industrial partners and other research institutions, has been in charge of the development of a suitable flowmeter: an ultrasonic device measuring simultaneously the water flow and the concentration of size classes of suspended particles. Working on the pulsed ultrasound principle, our multi-frequency device (1 to 14 MHz) allows flow velocity and water height measurement and estimation of suspended solids concentration. Velocity measurements rely on the coherent Doppler principle. A self developed frequency estimator, so called Spectral Identification method, was used and compared to the classical Pulse-Pair method. Several measurements campaigns on one wastewater collector of the French city of Strasbourg gave very satisfactory results and showed smaller standard deviation values for the Doppler frequency extracted by the Spectral Identification method. A specific algorithm was also developed for the water height measurements. It relies on the water surface acoustic impedance rupture and its peak localisation and behaviour in the collected backscattering data. This algorithm was positively tested on long time measurements on the same wastewater collector. A large part of the article is devoted to the measurements of the suspended solids concentrations. Our data analysis consists in the adaptation of the well described acoustic behaviour of sand to the behaviour of wastewater particles. Both acoustic attenuation and acoustic backscattering data over multiple frequencies are analyzed for the extrapolation of size classes and respective concentrations. Under dry weather conditions, the massic backscattering coefficient and the overall size distribution showed similar evolution whatever the measurement site was and were suggesting a global

  17. Field Installation and Real-Time Data Processing of the New Integrated SeismoGeodetic System with Real-Time Acceleration and Displacement Measurements for Earthquake Characterization Based on High-Rate Seismic and GPS Data

    NASA Astrophysics Data System (ADS)

    Zimakov, Leonid; Jackson, Michael; Passmore, Paul; Raczka, Jared; Alvarez, Marcos; Barrientos, Sergio

    2015-04-01

    We will discuss and show the results obtained from an integrated SeismoGeodetic System, model SG160-09, installed in the Chilean National Network. The SG160-09 provides the user high rate GNSS and accelerometer data, full epoch-by-epoch measurement integrity and, using the Trimble Pivot™ SeismoGeodetic App, the ability to create combined GNSS and accelerometer high-rate (200Hz) displacement time series in real-time. The SG160-09 combines seismic recording with GNSS geodetic measurement in a single compact, ruggedized package. The system includes a low-power, 220-channel GNSS receiver powered by the latest Trimble-precise Maxwell™6 technology and supports tracking GPS, GLONASS and Galileo signals. The receiver incorporates on-board GNSS point positioning using Real-Time Precise Point Positioning (PPP) technology with satellite clock and orbit corrections delivered over IP networks. The seismic recording element includes an ANSS Class A, force balance triaxial accelerometer with the latest, low power, 24-bit A/D converter, which produces high-resolution seismic data. The SG160-09 processor acquires and packetizes both seismic and geodetic data and transmits it to the central station using an advanced, error-correction protocol with back fill capability providing data integrity between the field and the processing center. The SG160-09 has been installed in the seismic station close to the area of the Iquique earthquake of April 1, 2014, in northern Chile, a seismically prone area at the current time. The hardware includes the SG160-09 system, external Zephyr Geodetic-2 GNSS antenna, and high-speed Internet communication media. Both acceleration and displacement data was transmitted in real-time to the National Seismological Center in Santiago for real-time data processing using Earthworm / Early Bird software. Command/Control of the field station and real-time GNSS position correction are provided via the Pivot software suite. Data from the SG160-09 system was

  18. Innovative real-time and non-destructive method of beam profile measurement under large beam current irradiation for BNCT

    NASA Astrophysics Data System (ADS)

    Takada, M.; Kamada, S.; Suda, M.; Fujii, R.; Nakamura, M.; Hoshi, M.; Sato, H.; Endo, S.; Hamano, T.; Arai, S.; Higashimata, A.

    2012-10-01

    We developed a real-time and non-destructive method of beam profile measurement on a target under large beam current irradiation, and without any complex radiation detectors or electrical circuits. We measured the beam profiles on a target by observing the target temperature using an infrared-radiation thermometer camera. The target temperatures were increased and decreased quickly by starting and stopping the beam irradiation within 1 s in response speed. Our method could trace beam movements rapidly. The beam size and position were calibrated by measuring O-ring heat on the target. Our method has the potential to measure beam profiles at beam current over 1 mA for proton and deuteron with the energy around 3 MeV and allows accelerator operators to adjust the beam location during beam irradiation experiments without decreasing the beam current.

  19. Measurement of avian cytokines with real time RT-PCR following infection with avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both functional and molecular techniques have been employed to measure the production of cytokines following influenza infection. Historically, the use of functional or antibody based techniques were employed in mammalian immunology. In avian immunology, only a few commercial antibodies are availa...

  20. In situ transmissiometer measurements for real-time monitoring of dust discharge during orchard nut harvesting.

    PubMed

    Downey, D; Giles, D K; Thompson, J F

    2008-01-01

    Rapid assessments of operating conditions and field preparation on dust discharge from nut harvesters are needed to guide improved equipment design and grower practices for dust reduction. An industrial opacity sensor, typically used for industrial stack monitoring, was adapted for use on a nut harvester to measure relative dust intensity during nut pick-up operations in almond orchards. Due to the high volume of discharge air and the presence of large debris such as leaves, additional components were coupled with the sensor to enable subsampling of the air. Pre-harvest windrow preparation conditions were evaluated. Results indicated that relative dust intensity decreased by 32% during harvest activities after windrow preparation with proper nut sweeper adjustment. Conventional harvesting results indicated that under typical operating conditions, reducing the separation fan speed could reduce relative dust intensity by 54%. Ground speed also had a strong effect; reducing speed from 4.8 to 2.4 km h(-1) reduced opacity of discharged air by 50%. The measurement system was also mounted on a separate vehicle and used as a tool for comparing modifications in harvest machine designs where direct measurement of discharge may not be feasible due to mechanical constraints. A comparison between a conventional harvester and one modification in the harvester design found that the machine modification decreased relative dust intensity by 73%. The measurement tools described in this work can be used to provide rapid feedback on harvester operating conditions, orchard cultural practices, and machine design modifications. PMID:18396543

  1. The Elastic Body Model: A Pedagogical Approach Integrating Real Time Measurements and Modelling Activities

    ERIC Educational Resources Information Center

    Fazio, C.; Guastella, I.; Tarantino, G.

    2007-01-01

    In this paper, we describe a pedagogical approach to elastic body movement based on measurements of the contact times between a metallic rod and small bodies colliding with it and on modelling of the experimental results by using a microcomputer-based laboratory and simulation tools. The experiments and modelling activities have been built in the…

  2. Real-time estimate of body kinematics during a planar squat task using a single inertial measurement unit.

    PubMed

    Bonnet, Vincent; Mazzà, Claudia; Fraisse, Philippe; Cappozzo, Aurelio

    2013-07-01

    This study aimed at the real-time estimation of the lower-limb joint and torso kinematics during a squat exercise, performed in the sagittal plane, using a single inertial measurement unit placed on the lower back. The human body was modeled with a 3-DOF planar chain. The planar IMU orientation and vertical displacement were estimated using one angular velocity and two acceleration components and a weighted Fourier linear combiner. The ankle, knee, and hip joint angles were thereafter obtained through a novel inverse kinematic module based on the use of a Jacobian pseudoinverse matrix and null-space decoupling. The aforementioned algorithms were validated on a humanoid robot for which the mechanical model used and the measured joint angles virtually exhibited no inaccuracies. Joint angles were estimated with a maximal error of 1.5°. The performance of the proposed analytical and experimental methodology was also assessed by conducting an experiment on human volunteers and by comparing the relevant results with those obtained through the more conventional photogrammetric approach. The joint angles provided by the two methods displayed differences equal to 3±1°. These results, associated with the real-time capability of the method, open the door to future field applications in both rehabilitation and sport. PMID:23392337

  3. Near-real-time measurement of trace volatile organic compounds from combustion processes using an on-line gas chromatography

    SciTech Connect

    Ryan, J.V.; Lemieux, P.M.; Preston, W.T.

    1998-12-31

    The US EPA`s current regulatory approach for combustion and incineration sources considers the use of real-time continuous emission monitors (CEMs) for particulate, metals, and organic compounds to monitor source emissions. Currently, the CEM technologies to support this approach have not been thoroughly developed and/or demonstrated. The EPA`s air Pollution Prevention and Control Division has developed a near-real-time volatile organic compound (VOC) CEM, using an on-line gas chromatograph (OLGC), capable of measuring over 20 VOCs at concentrations typically present in well-operated combustion systems. The OLGC system consists of a sample delivery system, a sample concentrator, and a GC equipped with both flame ionization and electron capture detectors. Application of the OLGC system was initially demonstrated through participation in the 1995 US EPA/DOE CEM demonstration program. Additional work has improved system performance, including increased automation and improved calibration technique. During pilot-scale incineration testing, measurement performance was examined in detail through comparisons to various CEM performance criteria. Specifically, calibration error, calibration drift error, and system bias were examined as a function of full scale and gas concentration. Although OLGC measurement performance was not able to meet standard EPA CEM measurement performance criteria, measurement performance was encouraging. The system demonstrated the ability to perform hourly trace level VOC measurements for as many as 23 different VOCs with boiling points ranging from {minus}23.7 to 180.5 C at a known level of measurement performance. This system is a suitable alternative to VOC reference method measurements which may be performed only intermittently.

  4. Noninvasive, real-time measurements of plasma parameters via optical emission spectroscopy

    SciTech Connect

    Wang Shicong; Wendt, Amy E.; Boffard, John B.; Lin, Chun C.; Radovanov, Svetlana; Persing, Harold

    2013-03-15

    Plasma process control applications require acquisition of diagnostic data at a rate faster than the characteristic timescale of perturbations to the plasma. Diagnostics based on optical emission spectroscopy of intense emission lines permit rapid noninvasive measurements with low-resolution ({approx}1 nm), fiber-coupled spectrographs, which are included on many plasma process tools for semiconductor processing. Here the authors report on rapid analysis of Ar emissions with such a system to obtain electron temperatures, electron densities, and metastable densities in argon and argon/mixed-gas (Ar/N{sub 2}, Ar/O{sub 2}, Ar/H{sub 2}) inductively coupled plasmas. Accuracy of the results (compared to measurements made by Langmuir probe and white-light absorption spectroscopy) are typically better than {+-}15% with a time resolution of 0.1 s, which is more than sufficient to capture the transient behavior of many processes, limited only by the time response of the spectrograph used.

  5. Quasi-real-time photon pulse duration measurement by analysis of FEL radiation spectra.

    PubMed

    Engel, Robin; Düsterer, Stefan; Brenner, Günter; Teubner, Ulrich

    2016-01-01

    For photon diagnostics at free-electron lasers (FELs), the determination of the photon pulse duration is an important challenge and a complex task. This is especially true for SASE FELs with strongly fluctuating pulse parameters. However, most techniques require an extensive experimental setup, data acquisition and evaluation time, limiting the usability in all-day operation. In contrast, the presented work uses an existing approach based on the analysis of statistical properties of measured SASE FEL spectra and implements it as a software tool, integrated in FLASH's data acquisition system. This allows the calculation of the average pulse durations from a set of measured spectral distributions with only seconds of delay, whenever high-resolution spectra are recorded. PMID:26698053

  6. Quasi-real-time photon pulse duration measurement by analysis of FEL radiation spectra

    PubMed Central

    Engel, Robin; Düsterer, Stefan; Brenner, Günter; Teubner, Ulrich

    2016-01-01

    For photon diagnostics at free-electron lasers (FELs), the determination of the photon pulse duration is an important challenge and a complex task. This is especially true for SASE FELs with strongly fluctuating pulse parameters. However, most techniques require an extensive experimental setup, data acquisition and evaluation time, limiting the usability in all-day operation. In contrast, the presented work uses an existing approach based on the analysis of statistical properties of measured SASE FEL spectra and implements it as a software tool, integrated in FLASH’s data acquisition system. This allows the calculation of the average pulse durations from a set of measured spectral distributions with only seconds of delay, whenever high-resolution spectra are recorded. PMID:26698053

  7. Measuring real-time performance in distributed-object-oriented systems

    NASA Astrophysics Data System (ADS)

    Widell, Niklas; Kihl, Maria; Nyberg, Christian

    1999-08-01

    The principles of distributed object oriented programming offer great possibilities for flexible architectures in multiple fields. In telecommunications, an architecture called Telecommunication Information Networking Architecture has been developed using these very principles. It allows telecommunication services to be implemented using software objects that in turn can be executed in a location transparent way in a network. The location transparency offers great flexibility for service creation, but as the software must be executed somewhere in the network on nodes of finite capacity, performance problems can arise due to inefficient placement of objects causing either overloaded nodes or excessive and unnecessary inter-node communication. To ensure good performance, various measures of load control and load balancing must be taken. We discuss how to measure the performance of a distributed object oriented system and examine two load balancing algorithms that can be used in such systems.

  8. Obtaining Reliable Predictions of Terrestrial Energy Coupling From Real-Time Solar Wind Measurement

    NASA Technical Reports Server (NTRS)

    Weimer, Daniel R.

    2001-01-01

    The first draft of a manuscript titled "Variable time delays in the propagation of the interplanetary magnetic field" has been completed, for submission to the Journal of Geophysical Research. In the preparation of this manuscript all data and analysis programs had been updated to the highest temporal resolution possible, at 16 seconds or better. The program which computes the "measured" IMF propagation time delays from these data has also undergone another improvement. In another significant development, a technique has been developed in order to predict IMF phase plane orientations, and the resulting time delays, using only measurements from a single satellite at L1. The "minimum variance" method is used for this computation. Further work will be done on optimizing the choice of several parameters for the minimum variance calculation.

  9. Real-time gastric motility monitoring using transcutaneous intraluminal impedance measurements (TIIM).

    PubMed

    Poscente, M D; Wang, G; Filip, D; Ninova, P; Yadid-Pecht, O; Andrews, C N; Mintchev, M P

    2014-02-01

    The stomach plays a critical role in digestion, processing ingested food mechanically and breaking it up into particles, which can be effectively and efficiently processed by the intestines. When the motility of the stomach is compromised, digestion is adversely affected. This can lead to a variety of disorders. Current diagnostic techniques for gastric motility disorders are seriously lacking, and are based more on eliminating other possibilities rather than on specific tests. Presently, gastric motility can be assessed by monitoring gastric emptying, food transit, intragastric pressures, etc. The associated tests are usually stationary and of relatively short duration. The present study proposes a new method of measuring gastric motility, utilizing the attenuation of an oscillator-induced electrical signal across the gastric tissue, which is modulated by gastric contractions. The induced high-frequency oscillator signal is generated within the stomach, and is picked up transluminally by cutaneous electrodes positioned on the abdominal area connected to a custom-designed data acquisition instrument. The proposed method was implemented in two different designs: first a transoral catheter was modified to emit the signal inside the stomach; and second, a gastric retentive pill was designed to emit the signal. Both implementations were applied in vivo on two mongrel dogs (25.50 kg and 25.75 kg). Gastric contractions were registered and quantitatively compared to recordings from force transducers sutured onto the serosa of the stomach. Gastric motility indices were calculated for each minute, with transluminal impedance measurements and the measurements from the force transducers showing statistically significant (p < 0.05) Pearson correlation coefficients (0.65 ± 0.08 for the catheter-based design and 0.77 ± 0.03 for the gastric retentive pill design). These results show that transcutaneous intraluminal impedance measurement has the potential with further research

  10. Laser spectroscopic real time measurements of methanogenic activity under simulated Martian subsurface analog conditions

    NASA Astrophysics Data System (ADS)

    Schirmack, Janosch; Böhm, Michael; Brauer, Chris; Löhmannsröben, Hans-Gerd; de Vera, Jean-Pierre; Möhlmann, Diedrich; Wagner, Dirk

    2014-08-01

    On Earth, chemolithoautothrophic and anaerobic microorganisms such as methanogenic archaea are regarded as model organisms for possible subsurface life on Mars. For this reason, the methanogenic strain Methanosarcina soligelidi (formerly called Methanosarcina spec. SMA-21), isolated from permafrost-affected soil in northeast Siberia, has been tested under Martian thermo-physical conditions. In previous studies under simulated Martian conditions, high survival rates of these microorganisms were observed. In our study we present a method to measure methane production as a first attempt to study metabolic activity of methanogenic archaea during simulated conditions approaching conditions of Mars-like environments. To determine methanogenic activity, a measurement technique which is capable to measure the produced methane concentration with high precision and with high temporal resolution is needed. Although there are several methods to detect methane, only a few fulfill all the needed requirements to work within simulated extraterrestrial environments. We have chosen laser spectroscopy, which is a non-destructive technique that measures the methane concentration without sample taking and also can be run continuously. In our simulation, we detected methane production at temperatures down to -5 °C, which would be found on Mars either temporarily in the shallow subsurface or continually in the deep subsurface. The pressure of 50 kPa which we used in our experiments, corresponds to the expected pressure in the Martian near subsurface. Our new device proved to be fully functional and the results indicate that the possible existence of methanogenic archaea in Martian subsurface habitats cannot be ruled out.

  11. Real-time weigh-in-motion measurement using fiber Bragg grating sensors

    NASA Astrophysics Data System (ADS)

    Huang, Ying; Palek, Leonard; Strommen, Robert; Worel, Ben; Chen, Genda

    2014-03-01

    Overloading truck loads have long been one of the key reasons for accelerating road damage, especially in rural regions where the design loads are expected to be small and in the cold regions where the wet-and-dry cycle places a significant role. To control the designed traffic loads and further guide the road design in future, periodical weight stations have been implemented for double check of the truck loads. The weight stations give chances for missing measurement of overloaded vehicles, slow down the traffic, and require additional labors. Infrastructure weight-in-motion sensors, on the other hand, keep consistent traffic flow and monitor all types of vehicles on roads. However, traditional electrical weight-in-motion sensors showed high electromagnetic interference (EMI), high dependence on environmental conditions such as moisture, and relatively short life cycle, which are unreliable for long-term weigh-inmotion measurements. Fiber Bragg grating (FBG) sensors, with unique advantages of compactness, immune to EMI and moisture, capability of quasi-distributed sensing, and long life cycle, will be a perfect candidate for long-term weigh-in-motion measurements. However, the FBG sensors also surfer from their frangible nature of glass materials for a good survive rate during sensor installation. In this study, the FBG based weight-in-motion sensors were packaged by fiber reinforced polymer (FRP) materials and further validated at MnROAD facility, Minnesota DOT (MnDOT). The design and layout of the FRP-FBG weight-in-motion sensors, their field test setup, data acquisition, and data analysis will be presented. Upon validation, the FRP-FBG sensors can be applied weigh-in-motion measurement to assistant road managements.

  12. Real-time, high-accuracy 3D imaging and shape measurement.

    PubMed

    Nguyen, Hieu; Nguyen, Dung; Wang, Zhaoyang; Kieu, Hien; Le, Minh

    2015-01-01

    In spite of the recent advances in 3D shape measurement and geometry reconstruction, simultaneously achieving fast-speed and high-accuracy performance remains a big challenge in practice. In this paper, a 3D imaging and shape measurement system is presented to tackle such a challenge. The fringe-projection-profilometry-based system employs a number of advanced approaches, such as: composition of phase-shifted fringe patterns, externally triggered synchronization of system components, generalized system setup, ultrafast phase-unwrapping algorithm, flexible system calibration method, robust gamma correction scheme, multithread computation and processing, and graphics-processing-unit-based image display. Experiments have shown that the proposed system can acquire and display high-quality 3D reconstructed images and/or video stream at a speed of 45 frames per second with relative accuracy of 0.04% or at a reduced speed of 22.5 frames per second with enhanced accuracy of 0.01%. The 3D imaging and shape measurement system shows great promise of satisfying the ever-increasing demands of scientific and engineering applications. PMID:25967028

  13. Local, real-time measurement of drying films of aqueous polymer solutions using active microrheology.

    PubMed

    Komoda, Yoshiyuki; Leal, L Gary; Squires, Todd M

    2014-05-13

    Oscillatory microdisk rheometry was applied to evaluate the evolution of the viscoelastic properties at the surface of a film of an aqueous solution of poly(vinyl alcohol) (PVA) during drying. The drying rate was measured concurrently, based upon measurements of the variation of film thickness. A fully hydrolyzed PVA solution shows a constant drying rate, while a less hydrolyzed PVA solution exhibits a decreased drying rate in the latter part of the drying process, which occurred at the same time as an increase of the elastic modulus. We suggest that this difference in behavior is a consequence of the fact that both the configuration of the PVA molecule and the strength of interaction with water depend on the degree to which the PVA is hydrolyzed. The polymer concentration at the film surface can be estimated from the measured viscosity at the surface for the fully hydrolyzed PVA solution, and this result then can be compared with two theoretical calculations: one in which the polymer concentration is assumed to remain uniform throughout the film, and the other in which the polymer concentration distribution is determined via a one-dimensional diffusion model. This comparison suggests that the polymer is first concentrated locally near the surface but later in the drying process the distribution of polymer becomes increasingly uniform, possibly due to a spontaneously generated convective flow inside the film. PMID:24725080

  14. Real time mass flux measurements of gas-solid suspensions at low velocities

    SciTech Connect

    Saunders, J H; Chao, B T; Soo, S L

    1981-01-01

    In previous work, measurement of the particulate mass flux was made based upon a novel electrostatic technique. A small conducting wire sensor was inserted in the flow and as each particle hit the sensor an individual pulse of current was identified. Through suitable electronic circuitry, the number of pulses in a given time were counted. This was a direct measure of the number of particle-probe collisions which was related to local particle mass flow. The technique is currently limited to monodisperse suspensions. A primary advantage of the impact counter system is that the output does not depend upon the magnitude of the actual charge transfer. As long as the pulses are sufficiently above the noise level, variations in charge transfer will not affect the measurement. For the current work, the technique was applied to vertical gas-solid flow where the fluid velocity was slightly above the particle terminal velocity. Under these conditions a sufficient signal to noise ratio was not found. The Cheng-Soo charge transfer theory indicated that the low particle-sensor impact velocity was responsible. The probe system was then modified by extracting a particulate sample isokinetically and accelerating the particles to a sufficient velocity by an area reduction in the sampling tube. With this technique the signal to noise ratio was about 12 to 1. Mass flux results are shown to compare favorably with filter collection and weighing.

  15. A lab in the field: real-time measurements of water quality and stable isotopes

    NASA Astrophysics Data System (ADS)

    Kirchner, J. W.; von Freyberg, J.

    2015-12-01

    Hydrological and bio-geochemical processes in catchments are largely determined by the flow pathways of water through the subsurface. While the properties of the input (precipitation) and the output (streamflow) can be monitored with relatively low expenditure, subsurface flow processes and travel times remain difficult to quantify. A comprehensive understanding of these physical mechanisms is, however, crucial for a sustainable management of water resources. Natural tracers, such as stable isotopes of water (18O and 2H), in combination with other water quality parameters allows for studying various hydrological and associated processes in great detail. To follow the dynamics in rapidly changing hydrologic systems, high temporal resolution measurements of water isotopes and other constituents is required. Here, we present first results from an extensive field experiment in Switzerland where rain- and river water samples are sampled and analyzed directly in the field every 30 minutes. With this, sample degradation during storage and transportation can be minimized. At the same time, errors due to the collection and handling of numerous water samples are avoided. The fully automated monitoring system is comprised of the newly developed Continuous Water Sampler Module (CoWS), which was coupled to a Picarro L2130-i Cavity Ring-Down Spectrometer (Picarro Inc., USA), to continuously measure 18O and 2H. Optical and electrochemical sensors together with a spectrometer probe monitor NO3-, DOC and physico-chemical parameters, such as oxygen content, pH, electrical conductivity (s::can Messtechnik GmbH, Vienna). An ion chromatograph (Metrohm, Switzerland) allows for precise measurements of the major anions and cations. For quality control, additional water samples are taken automatically at the same frequency and analyzed in the laboratory.

  16. REAL-TIME STABILITY AND PROFILE COMPARISON MEASUREMENTS BETWEEN TWO DIFFERENT LTPS.

    SciTech Connect

    QIAN, S.; WANG, D.J.

    2005-07-31

    The Long Trace Profiler (LTP) is a precise angle measurement instrument, with a sensitivity and accuracy that can be in the sub-micron radian range. LTP characteristics depend on the particular LTP system schematic design, and the quality of components and assembly. The conditions of temperature, alignment, and mirror support during the measurement process vary between different laboratories, which influences significantly the test repeatability and accuracy. In this paper we introduce a direct comparison method to test the same object at the same point in the same environment at the same time by using two LTPs, which significantly increases the reliability of the comparison. A compact, portable LTP (PTLTP), which can be carried to different laboratories around the world, is used for comparison testing. Stability Comparison experiments between the LTP II at the National Synchrotron Radiation Research Center (NSRRC), and the PTLTP of Brookhaven National Laboratory (BNL) reveal significant differences in performance between the instruments. The experiment is set up so that each optical head simultaneously records both its own sample probe beam and also the probe beam from the other optical head. The two probe beams are reflected from same point on the mirror. Tests show that the stability of the PTLTP with a monolithic beam splitter is 10 times better than the stability of the LTP II which has a separated beam splitter unit. A scheme for comparing scanning measurements of a mirror is introduced. Experimental results show a significant difference between the two LTPs due mainly to distortions in the optical components inside the optical head. A new scheme is proposed for further mirror comparison scanning tests.

  17. Physical Processes and Real-Time Chemical Measurement of the Insect Olfactory Environment

    PubMed Central

    Abrell, Leif; Hildebrand, John G.

    2009-01-01

    Odor-mediated insect navigation in airborne chemical plumes is vital to many ecological interactions, including mate finding, flower nectaring, and host locating (where disease transmission or herbivory may begin). After emission, volatile chemicals become rapidly mixed and diluted through physical processes that create a dynamic olfactory environment. This review examines those physical processes and some of the analytical technologies available to characterize those behavior-inducing chemical signals at temporal scales equivalent to the olfactory processing in insects. In particular, we focus on two areas of research that together may further our understanding of olfactory signal dynamics and its processing and perception by insects. First, measurement of physical atmospheric processes in the field can provide insight into the spatiotemporal dynamics of the odor signal available to insects. Field measurements in turn permit aspects of the physical environment to be simulated in the laboratory, thereby allowing careful investigation into the links between odor signal dynamics and insect behavior. Second, emerging analytical technologies with high recording frequencies and field-friendly inlet systems may offer new opportunities to characterize natural odors at spatiotemporal scales relevant to insect perception and behavior. Characterization of the chemical signal environment allows the determination of when and where olfactory-mediated behaviors may control ecological interactions. Finally, we argue that coupling of these two research areas will foster increased understanding of the physicochemical environment and enable researchers to determine how olfactory environments shape insect behaviors and sensory systems. PMID:18548311

  18. Interference-term real-time measurement for self-stabilized two-wave mixing in photorefractive crystals.

    PubMed

    Santos, P A; Cescato, L; Frejlich, J

    1988-11-01

    We report the real-time direct interference-term measurement for a two-wave-mixing experiment in photorefractive crystals. Knowledge of the interference term may provide information concerning diffraction efficiency, interference pattern-to-recorded hologram phase shift, and optical activity and anisotropic diffraction properties of these materials. This method comprises phase modulation of one of the interfering beams and synchronous detection of the first and second harmonics in the resulting output irradiance modulation. Simultaneous detection of both harmonics enables the measurement to be made even in strongly perturbed conditions, since one harmonic is used for measuring and the other is used for operating Bi(12)TiO(20) are reported. PMID:19746110

  19. Aerosol-fluorescence spectrum analyzer: real-time measurement of emission spectra of airborne biological particles

    NASA Astrophysics Data System (ADS)

    Hill, Steven C.; Pinnick, Ronald G.; Nachman, Paul; Chen, Gang; Chang, Richard K.; Mayo, Michael W.; Fernandez, Gilbert L.

    1995-10-01

    We have assembled an aerosol-fluorescence spectrum analyzer (AFS), which can measure the fluorescence spectra and elastic scattering of airborne particles as they flow through a laser beam. The aerosols traverse a scattering cell where they are illuminated with intense (50 kW/cm 2) light inside the cavity of an argon-ion laser operating at 488 nm. This AFS can obtain fluorescence spectra of individual dye-doped polystyrene microspheres as small as 0.5 mu m in diameter. The spectra obtained from microspheres doped with pink and green-yellow dyes are clearly different. We have also detected the fluorescence spectra of airborne particles (although not single particles) made from various

  20. Real-time measurement of inhaled and exhaled cigarette smoke: Implications for dose

    NASA Astrophysics Data System (ADS)

    McGrath, Conor; Warren, Nigel; Biggs, Philip; McAughey, John

    2009-02-01

    Inhalation of tobacco smoke aerosol is a two-step process involving puffing followed by inhalation. Measured smoke deposition efficiencies in the lung (20-70%) are greater than expected for smoke particles of 150 -- 250 nm count median diameter (CMD). Various mechanisms have been put forward to explain this enhanced deposition pattern, including coagulation, hygroscopic growth, condensation and evaporation, changes in composition, or changes in inhalation behaviour. This paper represents one of a series of studies seeking to better quantify smoke chemistry, inhalation behaviour and cumulative particle growth. The studies have been conducted to better understand smoke dosimetry and links to disease as part of a wider programme defining risk and potential harm reduction. In this study, the average CMD of inhaled smoke was 160 nm while the average CMD of exhaled smoke was 239 nm with an average growth factor of 1.5.

  1. Final Report for the SEED Project: ''Inexpensive Chemresistor Sensors for Real Time Ground Water Contamination Measurement''

    SciTech Connect

    HUGHES, ROBERT C.; DAVIS, CHAD E.; THOMAS, MICHAEL L.

    2002-04-01

    This report details some proof-of-principle experiments we conducted under a small, one year ($100K) grant from the Strategic Environmental Research and Development Program (SERDP) under the SERDP Exploratory Development (SEED) effort. Our chemiresistor technology had been developed over the last few years for detecting volatile organic compounds (VOCs) in the air, but these sensors had never been used to detect VOCs in water. In this project we tried several different configurations of the chemiresistors to find the best method for water detection. To test the effect of direct immersion of the (non-water soluble) chemiresistors in contaminated water, we constructed a fixture that allowed liquid water to pass over the chemiresistor polymer without touching the electrical leads used to measure the electrical resistance of the chemiresistor. In subsequent experiments we designed and fabricated probes that protected the chemiresistor and electronics behind GORE-TEX{reg_sign} membranes that allowed the vapor from the VOCs and the water to reach a submerged chemiresistor without allowing the liquids to touch the chemiresistor. We also designed a vapor flow-through system that allowed the headspace vapor from contaminated water to be forced past a dry chemiresistor array. All the methods demonstrated that VOCs in a high enough concentration in water can be detected by chemiresistors, but the last method of vapor phase exposure to a dry chemiresistor gave the fastest and most repeatable measurements of contamination. Answers to questions posed by SERDP reviewers subsequent to a presentation of this material are contained in the appendix.

  2. A Comprehensive Statistically-Based Method to Interpret Real-Time Flowing Measurements

    SciTech Connect

    Keita Yoshioka; Pinan Dawkrajai; Analis A. Romero; Ding Zhu; A. D. Hill; Larry W. Lake

    2007-01-15

    With the recent development of temperature measurement systems, continuous temperature profiles can be obtained with high precision. Small temperature changes can be detected by modern temperature measuring instruments such as fiber optic distributed temperature sensor (DTS) in intelligent completions and will potentially aid the diagnosis of downhole flow conditions. In vertical wells, since elevational geothermal changes make the wellbore temperature sensitive to the amount and the type of fluids produced, temperature logs can be used successfully to diagnose the downhole flow conditions. However, geothermal temperature changes along the wellbore being small for horizontal wells, interpretations of a temperature log become difficult. The primary temperature differences for each phase (oil, water, and gas) are caused by frictional effects. Therefore, in developing a thermal model for horizontal wellbore, subtle temperature changes must be accounted for. In this project, we have rigorously derived governing equations for a producing horizontal wellbore and developed a prediction model of the temperature and pressure by coupling the wellbore and reservoir equations. Also, we applied Ramey's model (1962) to the build section and used an energy balance to infer the temperature profile at the junction. The multilateral wellbore temperature model was applied to a wide range of cases at varying fluid thermal properties, absolute values of temperature and pressure, geothermal gradients, flow rates from each lateral, and the trajectories of each build section. With the prediction models developed, we present inversion studies of synthetic and field examples. These results are essential to identify water or gas entry, to guide flow control devices in intelligent completions, and to decide if reservoir stimulation is needed in particular horizontal sections. This study will complete and validate these inversion studies.

  3. A COMPREHENSIVE STATISTICALLY-BASED METHOD TO INTERPRET REAL-TIME FLOWING MEASUREMENTS

    SciTech Connect

    Pinan Dawkrajai; Analis A. Romero; Keita Yoshioka; Ding Zhu; A.D. Hill; Larry W. Lake

    2004-10-01

    In this project, we are developing new methods for interpreting measurements in complex wells (horizontal, multilateral and multi-branching wells) to determine the profiles of oil, gas, and water entry. These methods are needed to take full advantage of ''smart'' well instrumentation, a technology that is rapidly evolving to provide the ability to continuously and permanently monitor downhole temperature, pressure, volumetric flow rate, and perhaps other fluid flow properties at many locations along a wellbore; and hence, to control and optimize well performance. In this first year, we have made considerable progress in the development of the forward model of temperature and pressure behavior in complex wells. In this period, we have progressed on three major parts of the forward problem of predicting the temperature and pressure behavior in complex wells. These three parts are the temperature and pressure behaviors in the reservoir near the wellbore, in the wellbore or laterals in the producing intervals, and in the build sections connecting the laterals, respectively. Many models exist to predict pressure behavior in reservoirs and wells, but these are almost always isothermal models. To predict temperature behavior we derived general mass, momentum, and energy balance equations for these parts of the complex well system. Analytical solutions for the reservoir and wellbore parts for certain special conditions show the magnitude of thermal effects that could occur. Our preliminary sensitivity analyses show that thermal effects caused by near-wellbore reservoir flow can cause temperature changes that are measurable with smart well technology. This is encouraging for the further development of the inverse model.

  4. REAL TIME CONTINUOUS MEASUREMENTS OF [CO2] AND δ13C AT MULTIPLE LOCATIONS USING CAVITY ENHANCED LASER ABSORPTION

    NASA Astrophysics Data System (ADS)

    McAlexander, W. I.; Rau, G. H.; Dobeck, L.; Spangler, L.

    2009-12-01

    A commercial instrument (Los Gatos Research, model 908-0003) utilizing Cavity Enhanced Laser Absorption Spectroscopy was deployed in 2009 at the ZERT carbon release site (Bozeman, MT) for real time measurement of above-ground CO2 concentration and isotope ratio (δ13C). An automated switching system sampled 13 different locations in the field, as well as two known references, over an 8 day period. Real-time Keeling plots were constructed showing distinct signatures of soil (-27.0 ‰) and fossil (-56.0 ‰) sources compared to background air (-8.2 ‰). Instrument performance gave 0.2 ‰ precision with only 100 seconds of averaging per inlet. Sequential sampling of the various inlets gave a temporal and physical mapping of the CO2 release plume that is difficult to obtain using more conventional techniques. The figures show the nature and quality of the data from one of the locations. Details concerning instrument performance, systematics, calibration, and data processing will be discussed. Fig1: Time chart of CO2 concentration and isotope ratio δ13C from one of 13 sample inlet locations at ZERT release field, July, 2009. Fig2: Keeling plot of data from Fig1 illustrating the two source mixing of soil (-27 ‰) and fossil (-56 ‰) CO2 with background air.

  5. Real-Time Measurement Of Polyurethane Foam Reactions And Hydrogen-Bonding By FT-IR Spectroscopy

    NASA Astrophysics Data System (ADS)

    Davis, Bradley L.; Harthcock, Matthew A.; Christenson, C. P.; Turner, R. B.

    1989-12-01

    The reaction and hydrogen-bond formation kinetics which occur in polyurethane foams will have an ultimate effect on the properties of these materials. Measurement of several urethane and urea carbonyl absorptions (free and hydrogen-bonded) provides two important pieces of information: (1) the chemical reactions which occur and (2) the progression of hydrogen-bond formation after reaction has completed. An attenuated total reflectance (ATR) Fourier-transform infrared spectroscopic technique has been previously developed which allows real-time data to be obtained during the foaming reaction 1,2. The authors have adapted a similar system to studying foams in order to more quantitatively interpret the real-time data in terms of the complex hydrogen-bonding structure. The vibrational assignments used for the carbonyl region of polyurethane foam spectra are as follows: 1732 cm-1 free urethane 1712 free urea 1701 ordered hydrogen-bonded urethane 1699-1653 monodentate hydrogen-bonded urea (Fig. 1) 1641 bidentate/ordered hydrogen-bonded urea. (Fig. 1)

  6. Real-time Full-spectral Imaging and Affinity Measurements from 50 Microfluidic Channels using Nanohole Surface Plasmon Resonance†

    PubMed Central

    Lee, Si Hoon; Lindquist, Nathan C.; Wittenberg, Nathan J.; Jordan, Luke R.; Oh, Sang-Hyun

    2012-01-01

    With recent advances in high-throughput proteomics and systems biology, there is a growing demand for new instruments that can precisely quantify a wide range of receptor-ligand binding kinetics in a high-throughput fashion. Here we demonstrate a surface plasmon resonance (SPR) imaging spectroscopy instrument capable of extracting binding kinetics and affinities from 50 parallel microfluidic channels simultaneously. The instrument utilizes large-area (~cm2) metallic nanohole arrays as SPR sensing substrates and combines a broadband light source, a high-resolution imaging spectrometer and a low-noise CCD camera to extract spectral information from every channel in real time with a refractive index resolution of 7.7 × 10−6. To demonstrate the utility of our instrument for quantifying a wide range of biomolecular interactions, each parallel microfluidic channel is coated with a biomimetic supported lipid membrane containing ganglioside (GM1) receptors. The binding kinetics of cholera toxin b (CTX-b) to GM1 are then measured in a single experiment from 50 channels. By combining the highly parallel microfluidic device with large-area periodic nanohole array chips, our SPR imaging spectrometer system enables high-throughput, label-free, real-time SPR biosensing, and its full-spectral imaging capability combined with nanohole arrays could enable integration of SPR imaging with concurrent surface-enhanced Raman spectroscopy. PMID:22895607

  7. Ozone chemiluminescent detection of olefins: Potential applications for real-time measurements of natural hydrocarbon emissions

    SciTech Connect

    Marley, N.A.; Gaffney, J.S.; Cunningham, M.M.

    1997-10-01

    A chemiluminescence analyzer has been constructed that takes advantage of the temperature dependence of the ozone-hydrocarbon reaction. When operated at a temperature of 170 C, the analyzer functions as a total nonmethane hydrocarbon analyzer with sensitivities 10--1,000 times better than a conventional FID. However, with operation at varying temperatures, the chemiluminescent signal reflects the differences in rates of reaction of the hydrocarbons with ozone. Preliminary studies at room temperature indicated that the relative rates of reaction of isoprene, {alpha}-pinene, {beta}-pinene, and limonene with ozone correlated with the observed chemiluminescence signal. When hydrocarbons are grouped in classes of similar structure, their rates of reaction with electrophilic atmospheric oxidants (e.g., OH, O{sub 3}, NO{sub 3}) can be correlated with each other. By varying the temperature of the reaction chamber, the chemiluminescence analyzer can be tuned to more reactive classes of hydrocarbons. Therefore, the chemiluminescence analyzer has the ability to determine atmospheric hydrocarbon concentrations as a function of class and will also provide a measure of the atmospheric reactivity of the hydrocarbons.

  8. Tutorial: Understanding residual stress in polycrystalline thin films through real-time measurements and physical models

    NASA Astrophysics Data System (ADS)

    Chason, Eric; Guduru, Pradeep R.

    2016-05-01

    Residual stress is a long-standing issue in thin film growth. Better understanding and control of film stress would lead to enhanced performance and reduced failures. In this work, we review how thin film stress is measured and interpreted. The results are used to describe a comprehensive picture that is emerging of what controls stress evolution. Examples from multiple studies are discussed to illustrate how the stress depends on key parameters (e.g., growth rate, material type, temperature, grain size, morphology, etc.). The corresponding stress-generating mechanisms that have been proposed to explain the data are also described. To develop a fuller understanding, we consider the kinetic factors that determine how much each of these processes contributes to the overall stress under different conditions. This leads to a kinetic model that can predict the dependence of the stress on multiple parameters. The model results are compared with the experiments to show how this approach can explain many features of stress evolution.

  9. Measuring environmental impact by real time laser differential displacement technique in simulated climate conditions

    NASA Astrophysics Data System (ADS)

    Tornari, Vivi; Bernikola, Eirini; Tsigarida, Nota; Hatzigiannakis, Kostas; Andrianakis, Michalis; Leissner, Johanna

    2015-06-01

    Environmental impact on artworks has always been a big issues for preservation of Cultural Heritage. Nowadays with the climate change it is experienced a slow but steady process of temperature increase affecting relative humidity which fluctuates while materials attempt to keep moisture balance. During repetitive equilibrium courses fatigue accumulates endangering the structural integrity prior to fracture. Assessing the risk imposed by the fluctuation allow preventive actions to take place and avoid interventive restoration action after fracture. A methodology is presented employing full-field interferometry by surface probing illumination based on direct realtime recording of surface images from delicate hygroscopic surfaces as they deform to dimensionally respond to relative humidity (RH) changes. The developed methodology aims to develop an early stage risk indicator tool to allow preventive measures directly through surface readings. The presented study1 aiming to experimentally highlight acclimatisation structural phenomena and to verify assumed standards in RH safety range based on the newly introduced concept of deformation threshold value is described and demonstrated with indicative results.

  10. Accurate thickness measurement of graphene

    NASA Astrophysics Data System (ADS)

    Shearer, Cameron J.; Slattery, Ashley D.; Stapleton, Andrew J.; Shapter, Joseph G.; Gibson, Christopher T.

    2016-03-01

    Graphene has emerged as a material with a vast variety of applications. The electronic, optical and mechanical properties of graphene are strongly influenced by the number of layers present in a sample. As a result, the dimensional characterization of graphene films is crucial, especially with the continued development of new synthesis methods and applications. A number of techniques exist to determine the thickness of graphene films including optical contrast, Raman scattering and scanning probe microscopy techniques. Atomic force microscopy (AFM), in particular, is used extensively since it provides three-dimensional images that enable the measurement of the lateral dimensions of graphene films as well as the thickness, and by extension the number of layers present. However, in the literature AFM has proven to be inaccurate with a wide range of measured values for single layer graphene thickness reported (between 0.4 and 1.7 nm). This discrepancy has been attributed to tip-surface interactions, image feedback settings and surface chemistry. In this work, we use standard and carbon nanotube modified AFM probes and a relatively new AFM imaging mode known as PeakForce tapping mode to establish a protocol that will allow users to accurately determine the thickness of graphene films. In particular, the error in measuring the first layer is reduced from 0.1-1.3 nm to 0.1-0.3 nm. Furthermore, in the process we establish that the graphene-substrate adsorbate layer and imaging force, in particular the pressure the tip exerts on the surface, are crucial components in the accurate measurement of graphene using AFM. These findings can be applied to other 2D materials.

  11. Evaluation of a method for measuring vehicular PM with a composite filter and a real-time BC instrument

    NASA Astrophysics Data System (ADS)

    Kamboures, Michael A.; Rieger, Paul L.; Zhang, Sherry; Sardar, Satya B.; Chang, M.-C. Oliver; Huang, Shiou-Mei; Dzhema, Inna; Fuentes, Mark; Benjamin, Michael T.; Hebert, Annette; Ayala, Alberto

    2015-12-01

    As part of the California Air Resources Board's effort to confirm the ability of the vehicular particulate matter (PM) reference method (RM) to measure PM emissions at sub-one milligram per mile (mg/mi), and to explore alternative methods, we evaluated a combination method (CM) that utilizes both gravimetric and real-time particle quantification. PM, collected on a single composite filter is apportioned to the three Federal Test Procedure (FTP) cycle phases using real-time equivalent black carbon (EBC) measurements, reducing the need to carry out separate gravimetric filter measurements for each of the test phases. Four light-duty gasoline vehicles, emitting PM at or below one mg/mi, were dynamometer tested repeatedly on the FTP cycle. PM was quantified by the RM and by two variants of the CM. One variant used photoacoustic spectroscopy to measure EBC (CM-MSS), and the other used an Aethalometer (CM-AE51). The CM was evaluated on repeatability, bias, and correlation with the RM. For the tested vehicles, the observed repeatability of the CM was superior to the RM regardless of the mode of EBC measurement or the test vehicle considered (σCM-MSS = 0.08 mg/mi, σCM-AE51 = 0.07 mg/mi, σRM ≈ 0.11 mg/mi). However, the CM was negatively biased by -0.08 mg/mi, versus the RM, in one of the test vehicles. We attribute the bias in this vehicle's data to organic carbon emissions that were not equivalently collected on the composite filter of the CM. When all data were combined, the correlation between the methods was good (R = 0.90 for CM-MSS vs. RM and R = 0.91 for CM-AE51 vs. RM).

  12. Near real-time ORM measurements and SVD matrix generation for 10 Hz global orbit feedback in RHIC

    SciTech Connect

    Liu, C.; Hulsart, R.; MacKay, W.; Marusic, A.; Mernick, K.; Michnoff, R.; Minty, M.

    2011-03-28

    To reduce the effect of trajectory perturbations ({approx}10 Hz) due to vibrations of the final focusing quadrupoles at RHIC, global orbit feedback was successfully prototyped during run-10. After upgraded to a system with 36 BPMs and 12 correctors, 10 Hz feedback was tested successfully in Run-11 and is in operational status for physics program. The test and operation of the system has been performed using transfer functions between the beam position monitors and correctors obtained from the online optics model and a correction algorithm based on singular value decomposition (SVD). One of our goals is to self-calibrate the system using SVD matrices derived from orbit response matrix (ORM) measurements acquired real-time using the new FPGA-based signal processing. Comparisons between measurement matrix and model matrix and the generation of SVD matrix for the feedback operation are presented.

  13. Research requirements for a real-time flight measurements and data analysis system for subsonic transport high-lift research

    NASA Technical Reports Server (NTRS)

    Whitehead, Julia H.; Harris, Franklin K.; Lytle, Carroll D.

    1993-01-01

    A multiphased research program to obtain detailed flow characteristics on a multielement high-lift flap system is being conducted on the Transport Systems Research Vehicle (B737-100 aircraft) at NASA Langley Research Center. Upcoming flight tests have required the development of a highly capable and flexible flight measurement and data analysis instrumentation system. This instrumentation system will be more comprehensive than any of the systems used on previous high-lift flight experiment at NASA Langley. The system will provide the researcher near-real-time information for decision making needed to modify a flight test in order to further examine unexpected flow conditions. This paper presents the research requirements and instrumentation design concept for an upcoming flight experiment for the subsonic transport high-lift research program. The flight experiment objectives, the measurement requirements, the data acquisition system, and the onboard data analysis and display capabilities are described.

  14. Real-time, high-resolution x-ray diffraction measurements on shocked crystals at a synchrotron facility

    NASA Astrophysics Data System (ADS)

    Gupta, Y. M.; Turneaure, Stefan J.; Perkins, K.; Zimmerman, K.; Arganbright, N.; Shen, G.; Chow, P.

    2012-12-01

    The Advanced Photon Source (APS) at Argonne National Laboratory was used to obtain real-time, high-resolution x-ray diffraction measurements to determine the microscopic response of shock-compressed single crystals. Disk shaped samples were subjected to plane shock wave compression by impacting them with half-inch diameter, flat-faced projectiles. The projectiles were accelerated to velocities ranging between 300 and 1200 m/s using a compact powder gun designed specifically for use at a synchrotron facility. The experiments were designed to keep the sample probed volume under uniaxial strain and constant stress for a duration longer than the 153.4 ns spacing between x-ray bunches. X-rays from a single pulse (<100 ps duration) out of the periodic x-ray pulses emitted by the synchrotron were used for the diffraction measurements. A synchronization and x-ray detection technique was developed to ensure that the measured signal was obtained unambiguously from the desired x-ray pulse incident on the sample while the sample was in a constant uniaxial strain state. The synchronization and x-ray detection techniques described can be used for a variety of x-ray measurements on shock compressed solids and liquids at the APS. Detailed procedures for applying the Bragg-Brentano parafocusing approach to single crystals at the APS are presented. Analytic developments to determine the effects of crystal substructure and non-ideal geometry on the diffraction pattern position and shape are presented. Representative real-time x-ray diffraction data, indicating shock-induced microstructural changes, are presented for a shock-compressed Al(111) sample. The experimental developments presented here provided, in part, the impetus for the Dynamic Compression Sector (DCS) currently under development at the APS. Both the synchronization/x-ray detection methods and the analysis equations for high-resolution single crystal x-ray diffraction can be used at the DCS.

  15. Real time measurements of sediment transport and bed morphology during channel altering flow and sediment transport events

    NASA Astrophysics Data System (ADS)

    Curran, Joanna Crowe; Waters, Kevin A.; Cannatelli, Kristen M.

    2015-09-01

    Real-time measurements of bed changes over a reach are a missing piece needed to link bed morphology with sediment transport processes during unsteady flows when the bed adjusts quickly to changing transport rates or visual observation of the bed is precluded by fine sediment in the water column. A new technique is presented that provides continuous measurement of sediment movement over the length of a flume. A bedload monitoring system (BLMS) was developed that makes use of pressure pillows under a false flume bottom to measure sediment and water weights over discrete flume channel sections throughout a flow event. This paper details the construction of the BLMS and provides examples of its use in a laboratory setting to reconstruct bed slopes during unsteady flows and to create a real-time record of sediment transport rates across the flume channel bed during a sediment transporting flow. Data gathered from the BLMS compared well against techniques commonly in use in flume studies. When the BLMS was analyzed in conjunction with bed surface DEMs and differenced DEMs, a complete transport and bed adjustment picture was constructed. The difference DEMs provided information on the spatial extent of bed morphology changes. The BLMS supplied the data record necessary to reconstruct sediment transport records through the downstream channel, including locations and time periods of temporary sediment storage and supply. The BLMS makes it possible to construct a continuous record of the spatial distribution of sediment movement through the flume, including areas of temporary aggradation and degradation. Exciting implications of future research that incorporates a BLMS include a more informed management of river systems as a result of improved temporal predictions of sediment movement and the associated changes in channel slope and bed morphology.

  16. Direct, Real-Time Measurement of Shear Stress-Induced Nitric Oxide Produced from Endothelial Cells In Vitro

    PubMed Central

    Andrews, Allison M.; Jaron, Dov; Buerk, Donald G.; Kirby, Patrick L.; Barbee, Kenneth A.

    2010-01-01

    Nitric oxide (NO) produced by the endothelium is involved in the regulation of vascular tone. Decreased NO production or availability has been linked to endothelial dysfunction in hypercholesterolemia and hypertension. Shear stress-induced NO release is a well-established phenomenon, yet the cellular mechanisms of this response are not completely understood. Experimental limitations have hindered direct, real-time measurements of NO under flow conditions. We have overcome these challenges with a new design for a parallel-plate flow chamber. The chamber consists of two compartments, separated by a Transwell® membrane, which isolates a NO recording electrode located in the upper compartment from flow effects. Endothelial cells are grown on the bottom of the membrane, which is inserted into the chamber flush with the upper plate. We demonstrate for the first time direct real-time NO measurements from endothelial cells with controlled variations in shear stress. Step changes in shear stress from 0.1 dyn/cm2 to 6, 10 or 20 dyn/cm2 elicited a transient decrease in NO followed by an increase to a new steady state. An analysis of NO transport suggests that the initial decrease is due to the increased removal rate by convection as flow increases. Furthermore, the rate at which the NO concentration approaches the new steady state is related to the time-dependent cellular response rather than transport limitations of the measurement configuration. Our design offers a method for studying the kinetics of the signaling mechanisms linking NO production with shear stress as well as pathological conditions involving changes in NO production or availability. PMID:20719252

  17. REAL TIME SYSTEM OPERATIONS 2006-2007

    SciTech Connect

    Eto, Joseph H.; Parashar, Manu; Lewis, Nancy Jo

    2008-08-15

    The Real Time System Operations (RTSO) 2006-2007 project focused on two parallel technical tasks: (1) Real-Time Applications of Phasors for Monitoring, Alarming and Control; and (2) Real-Time Voltage Security Assessment (RTVSA) Prototype Tool. The overall goal of the phasor applications project was to accelerate adoption and foster greater use of new, more accurate, time-synchronized phasor measurements by conducting research and prototyping applications on California ISO's phasor platform - Real-Time Dynamics Monitoring System (RTDMS) -- that provide previously unavailable information on the dynamic stability of the grid. Feasibility assessment studies were conducted on potential application of this technology for small-signal stability monitoring, validating/improving existing stability nomograms, conducting frequency response analysis, and obtaining real-time sensitivity information on key metrics to assess grid stress. Based on study findings, prototype applications for real-time visualization and alarming, small-signal stability monitoring, measurement based sensitivity analysis and frequency response assessment were developed, factory- and field-tested at the California ISO and at BPA. The goal of the RTVSA project was to provide California ISO with a prototype voltage security assessment tool that runs in real time within California ISO?s new reliability and congestion management system. CERTS conducted a technical assessment of appropriate algorithms, developed a prototype incorporating state-of-art algorithms (such as the continuation power flow, direct method, boundary orbiting method, and hyperplanes) into a framework most suitable for an operations environment. Based on study findings, a functional specification was prepared, which the California ISO has since used to procure a production-quality tool that is now a part of a suite of advanced computational tools that is used by California ISO for reliability and congestion management.

  18. Real-time measurement of joint movement using a digital signal processor-based image processing system

    NASA Astrophysics Data System (ADS)

    Moorehead, John D.; Harvey, David M.; Dangerfield, Peter H.; Montgomery, S. C.

    1994-09-01

    A new low cost imaging system has been devised to detect and measure joint movement to help with the diagnosis of ligament injuries in the human knee. The system uses a domestic video camcorder to record the movement of marks on a patient's knee as it is flexed. The pictures are then fed into the imaging system, where the coordinates of each mark are determined for each angle of flexion. The coordinate data is then processed to show the dynamic operation of the knee, from which an assessment of ligament damage can be made. The imaging system is comprised of a PC host, a commercial frame store, and a custom built TMS320C40 digital signal processor (dsp) board. The dsp is used to perform correlation and other imaging functions, to automatically determine the mark coordinates in real time. This paper describes the application and development of the system, and gives the results of the research to date.

  19. A real time dynamic data acquisition and processing system for velocity, density, and total temperature fluctuation measurements

    NASA Technical Reports Server (NTRS)

    Clukey, Steven J.

    1991-01-01

    The real time Dynamic Data Acquisition and Processing System (DDAPS) is described which provides the capability for the simultaneous measurement of velocity, density, and total temperature fluctuations. The system of hardware and software is described in context of the wind tunnel environment. The DDAPS replaces both a recording mechanism and a separate data processing system. DDAPS receives input from hot wire anemometers. Amplifiers and filters condition the signals with computer controlled modules. The analog signals are simultaneously digitized and digitally recorded on disk. Automatic acquisition collects necessary calibration and environment data. Hot wire sensitivities are generated and applied to the hot wire data to compute fluctuations. The presentation of the raw and processed data is accomplished on demand. The interface to DDAPS is described along with the internal mechanisms of DDAPS. A summary of operations relevant to the use of the DDAPS is also provided.

  20. 15 years of SO2 measurements at Popocatépetl volcano: from individual COSPEC measurements to real-time mini-DOAS-network measurements

    NASA Astrophysics Data System (ADS)

    Delgado Granados, Hugo; Cárdenas González, Lucio; Alvarez Nieves, José Manuel

    2010-05-01

    On December 21, 1994, Popocatépetl Volcano (PV) started to erupt explosively with a series of vulcanian-type events with large emissions of gas. The activity remained explosive along 1995 with a period of quiescence from August 1995 to early March 1996. On March 5, 1996 the volcano resumed the eruptive activity (vulcanian in nature) and on March 25 the eruptive style changed to effusive. The first lava dome was partially destroyed on April 30, 1996. Up to 2001, at least 12 lava domes were extruded and destroyed. Until December 2009, PV continues producing lava domes, and destroying them with vulcanian explosions. Here, a summary of the SO2 emissions at PV during the last 15 years is presented. Work on PV's gas emissions started in early 1994. Initially, on February 1st 1994, SO2 emissions were 16 kg/s measured with a correlation spectrometer (COSPEC). Gas emissions prior to the eruption were of a magmatic signature, and with a similar order-of-magnitude as emissions during the first year of eruption (10s-100s kg/ s). The values during the period between August 1995 and early March 1996 were ~9 kg/s in average (maximum of ~19 kg/s, and a minimum of ~1 kg/s). After 1996 the order-of-magnitude raised to an average of ~130 kg/s. SO2 emissions have had a high variability through time the maximum value was measured on December 13, 2000 (~2000 kg/s). Within the framework of the NOVAC (Network for the Observation of Volcanic and Atmospheric Change) project 4 mini-DOAS instruments have been deployed at PV, all stations acquire spectra in real-time and send the data to the receiving station at CENAPRED in Mexico City where data is collected for immediate evaluation of the volcanic activity. Automatically, data is also sent to a server in Chalmers University for archiving and other uses. Data is post-processed at CENAPRED and UNAM and a database is being built since 2005. These measurements allow to estimate SO2 emissions in real-time and in a more accurate way. The network

  1. Real time Faraday spectrometer

    DOEpatents

    Smith, Jr., Tommy E.; Struve, Kenneth W.; Colella, Nicholas J.

    1991-01-01

    This invention uses a dipole magnet to bend the path of a charged particle beam. As the deflected particles exit the magnet, they are spatially dispersed in the bend-plane of the magnet according to their respective momenta and pass to a plurality of chambers having Faraday probes positioned therein. Both the current and energy distribution of the particles is then determined by the non-intersecting Faraday probes located along the chambers. The Faraday probes are magnetically isolated from each other by thin metal walls of the chambers, effectively providing real time current-versus-energy particle measurements.

  2. The Performance Analysis of a Real-Time Integrated INS/GPS Vehicle Navigation System with Abnormal GPS Measurement Elimination

    PubMed Central

    Chiang, Kai-Wei; Duong, Thanh Trung; Liao, Jhen-Kai

    2013-01-01

    The integration of an Inertial Navigation System (INS) and the Global Positioning System (GPS) is common in mobile mapping and navigation applications to seamlessly determine the position, velocity, and orientation of the mobile platform. In most INS/GPS integrated architectures, the GPS is considered to be an accurate reference with which to correct for the systematic errors of the inertial sensors, which are composed of biases, scale factors and drift. However, the GPS receiver may produce abnormal pseudo-range errors mainly caused by ionospheric delay, tropospheric delay and the multipath effect. These errors degrade the overall position accuracy of an integrated system that uses conventional INS/GPS integration strategies such as loosely coupled (LC) and tightly coupled (TC) schemes. Conventional tightly coupled INS/GPS integration schemes apply the Klobuchar model and the Hopfield model to reduce pseudo-range delays caused by ionospheric delay and tropospheric delay, respectively, but do not address the multipath problem. However, the multipath effect (from reflected GPS signals) affects the position error far more significantly in a consumer-grade GPS receiver than in an expensive, geodetic-grade GPS receiver. To avoid this problem, a new integrated INS/GPS architecture is proposed. The proposed method is described and applied in a real-time integrated system with two integration strategies, namely, loosely coupled and tightly coupled schemes, respectively. To verify the effectiveness of the proposed method, field tests with various scenarios are conducted and the results are compared with a reliable reference system. PMID:23955434

  3. The performance analysis of a real-time integrated INS/GPS vehicle navigation system with abnormal GPS measurement elimination.

    PubMed

    Chiang, Kai-Wei; Duong, Thanh Trung; Liao, Jhen-Kai

    2013-01-01

    The integration of an Inertial Navigation System (INS) and the Global Positioning System (GPS) is common in mobile mapping and navigation applications to seamlessly determine the position, velocity, and orientation of the mobile platform. In most INS/GPS integrated architectures, the GPS is considered to be an accurate reference with which to correct for the systematic errors of the inertial sensors, which are composed of biases, scale factors and drift. However, the GPS receiver may produce abnormal pseudo-range errors mainly caused by ionospheric delay, tropospheric delay and the multipath effect. These errors degrade the overall position accuracy of an integrated system that uses conventional INS/GPS integration strategies such as loosely coupled (LC) and tightly coupled (TC) schemes. Conventional tightly coupled INS/GPS integration schemes apply the Klobuchar model and the Hopfield model to reduce pseudo-range delays caused by ionospheric delay and tropospheric delay, respectively, but do not address the multipath problem. However, the multipath effect (from reflected GPS signals) affects the position error far more significantly in a consumer-grade GPS receiver than in an expensive, geodetic-grade GPS receiver. To avoid this problem, a new integrated INS/GPS architecture is proposed. The proposed method is described and applied in a real-time integrated system with two integration strategies, namely, loosely coupled and tightly coupled schemes, respectively. To verify the effectiveness of the proposed method, field tests with various scenarios are conducted and the results are compared with a reliable reference system. PMID:23955434

  4. Radiation dosimetry measurements with real time radiation monitoring device (RRMD)-II in Space Shuttle STS-79

    NASA Technical Reports Server (NTRS)

    Sakaguchi, T.; Doke, T.; Hayashi, T.; Kikuchi, J.; Hasebe, N.; Kashiwagi, T.; Takashima, T.; Takahashi, K.; Nakano, T.; Nagaoka, S.; Takahashi, S.; Yamanaka, H.; Yamaguchi, K.; Badhwar, G. D.

    1997-01-01

    The real-time measurement of radiation environment was made with an improved real-time radiation monitoring device (RRMD)-II onboard Space Shuttle STS-79 (S/MM#4: 4th Shuttle MIR Mission, at an inclination angle of 51.6 degrees and an altitude of 250-400km) for 199 h during 17-25 September, 1996. The observation of the detector covered the linear energy transfer (LET) range of 3.5-6000 keV/micrometer. The Shuttle orbital profile in this mission was equivalent to that of the currently planned Space Station, and provided an opportunity to investigate variations in count rate and dose equivalent rate depending on altitude, longitude, and latitude in detail. Particle count rate and dose equivalent rate were mapped geographically during the mission. Based on the map of count rate, an analysis was made by dividing whole region into three regions: South Atlantic Anomaly (SAA) region, high latitude region and other regions. The averaged absorbed dose rate during the mission was 39.3 microGy/day for a LET range of 3.5-6000 keV/micrometer. The corresponding average dose equivalent rates during the mission are estimated to be 293 microSv/day with quality factors from International Commission on Radiological Protection (ICRP)-Pub. 60 and 270 microSv/day with quality factors from ICRP-Pub. 26. The effective quality factors for ICRP-Pub. 60 and 26 are 7.45 and 6.88, respectively. From the present data for particles of LET > 3.5keV/micrometer, we conclude that the average dose equivalent rate is dominated by the contribution of galactic cosmic ray (GCR) particles. The dose-detector depth dependence was also investigated.

  5. The Smallest R/V: A Small-scale Ocean Exploration Demonstration of Real-time Bathymetric Measurements

    NASA Astrophysics Data System (ADS)

    Howell, S. M.; Boston, B.; Maher, S. M.; Sleeper, J. D.; Togia, H.; Tree, J. P.

    2014-12-01

    In October 2013, graduate student members of the University of Hawaii Geophysical Society designed a small-scale model research vessel (R/V) that uses sonar to create 3D maps of a model seafloor in real-time. This pilot project was presented to the public at the School of Ocean and Earth Science and Technology's (SOEST) Biennial Open House weekend. An estimated 7,600 people attended the two-day event, including children and teachers from Hawaii's schools, home school students, community groups, families, and science enthusiasts. Our exhibit demonstrated real-time sonar mapping of a cardboard volcano using a toy size research vessel on a fixed 2D model ship track suspended above a model seafloor. Sound wave travel times were recorded using an unltrasonic emitter/receiver attached to an Arduino microcontroller platform, while the same system measured displacement along the ship track. This data was streamed through a USB connection to a PC running MatLab, where a 3D model was updated as the ship collected data. Our exhibit demonstrates the practical use of complicated concepts, like wave physics and data processing, in a way that even the youngest elementary students are able to understand. It provides an accessible avenue to learn about sonar mapping, and could easily be adapted to talk about bat and marine mammal echolocation by replacing the model ship and volcano. The exhibit received an overwhelmingly positive response from attendees, and has inspired the group to develop a more interactive model for future exhibitions, using multiple objects to be mapped that participants could arrange, and a more robust ship movement system that participants could operate.

  6. Real-time optoacoustic monitoring during thermotherapy

    NASA Astrophysics Data System (ADS)

    Esenaliev, Rinat O.; Larina, Irina V.; Larin, Kirill V.; Motamedi, Massoud

    2000-05-01

    Optoacoustic monitoring of tissue optical properties and speed of sound in real time can provide fast and accurate feedback information during thermotherapy performed with various heating or cooling agents. Amplitude and temporal characteristics of optoacoustic pressure waves are dependent on tissue properties. Detection and measurement of the optoacoustic waves may be used to monitor the extent of tissue hyperthermia, coagulation, or freezing with high resolution and contrast. We studied real-time optoacoustic monitoring of thermal coagulation induced by conductive heating and laser radiation and cryoablation with liquid nitrogen. Q-switched Nd:YAG laser pulses were used as probing radiation to induce optoacoustic waves in tissues. Dramatic changes in optoacoustic signal parameters were detected during tissue freezing and coagulation due to sharp changes in tissue properties. The dimensions of thermally- induced lesions were measured in real time with the optoacoustic technique. Our studies demonstrated that the laser optoacoustic technique is capable of real-time monitoring of tissue coagulation and freezing front with submillimeter spatial resolution. This may allow accurate thermal ablation or cryotherapy of malignant and benign lesions with minimal damage to normal tissues.

  7. New Measurements and Modeling Capability to Improve Real-time Forecast of Cascadia Tsunamis along U.S. West Coast

    NASA Astrophysics Data System (ADS)

    Wei, Y.; Titov, V. V.; Bernard, E. N.; Spillane, M. C.

    2014-12-01

    The tragedies of 2004 Sumatra and 2011 Tohoku tsunamis exposed the limits of our knowledge in preparing for devastating tsunamis, especially in the near field. The 1,100-km coastline of the Pacific coast of North America has tectonic and geological settings similar to Sumatra and Japan. The geological records unambiguously show that the Cascadia fault had caused devastating tsunamis in the past and this geological process will cause tsunamis in the future. Existing observational instruments along the Cascadia Subduction Zone are capable of providing tsunami data within minutes of tsunami generation. However, this strategy requires separation of the tsunami signals from the overwhelming high-frequency seismic waves produced during a strong earthquake- a real technical challenge for existing operational tsunami observational network. A new-generation of nano-resolution pressure sensors can provide high temporal resolution of the earthquake and tsunami signals without loosing precision. The nano-resolution pressure sensor offers a state-of the-science ability to separate earthquake vibrations and other oceanic noise from tsunami waveforms, paving the way for accurate, early warnings of local tsunamis. This breakthrough underwater technology has been tested and verified for a couple of micro-tsunami events (Paros et al., 2011). Real-time forecast of Cascadia tsunamis is becoming a possibility with the development of nano-tsunameter technology. The present study provides an investigation on optimizing the placement of these new sensors so that the forecast time can be shortened.. The presentation will cover the optimization of an observational array to quickly detect and forecast a tsunami generated by a strong Cascadia earthquake, including short and long rupture scenarios. Lessons learned from the 2011 Tohoku tsunami will be examined to demonstrate how we can improve the local forecast using the new technology We expect this study to provide useful guideline for

  8. Transpiration and Evaporation measurements in a Mountain Ecosystem using Real-Time Field-Based Water Vapor Isotopes (Invited)

    NASA Astrophysics Data System (ADS)

    Dominguez, F.; Gochis, D. J.; Harley, P. C.; Turnipseed, A.; Hu, J.

    2010-12-01

    The partitioning of evapotranspiration between evaporation from bare soil and transpiration by vegetation is not adequately represented in land surface models coupled to atmospheric models. In this work we present measurements of stable water vapor isotopes (δD and δ18O) in Manitou Experimental Forest. At an elevation of approximately 2,400m in the Rocky Mountain foothills-pediment region the site is characterized by Ponderosa pine and a grass understory. We use a portable real time isotopic water vapor analyzer that allows us to partition evapotranspiration from the vegetated region into transpiration from plants and direct evaporation from the soil and canopy. The isotopic measurements are complementary to data from a network of eddy covariance towers and soil moisture measurements. We give particular emphasis to the temporal variability of the isotopic signature of transpiration presenting simultaneous measurements of water vapor isotopes, net photosynthesis, evapotranspiration and stomatal conductance measured using a dynamic flow-through gas exchange system. These observations are the first step towards improving our understanding and numerical modeling of the partitioning between evaporation and transpiration.

  9. Laser-induced fluorescence over optical fibers for real time in situ measurement of petroleum hydrocarbons in seawater

    NASA Astrophysics Data System (ADS)

    Lieberman, S. H.; Inman, S. M.; Theriault, G. A.

    1993-04-01

    A fiber optic-based fluorometer system is described that uses a pulsed laser to induce fluorescence and a time-gated linear photodiode array coupled to a spectrograph for rapid measurement of fluorescence emission spectra and fluorescence decay times. Data is presented from studies conducted in San Diego Bay where the system has been used for real-time in situ measurements of temporal and spatial variability of petroleum hydrocarbons in seawater. Results show that the optical fiber fluorometer system is capable of direct quantification of low level (parts-per-billion diesel fuel marine equivalent) concentrations of petroleum hydrocarbons. Analysis times for measurement of complete fluorescence emission spectra are fast (tens of milliseconds) and compare with the temporal response characteristics for temperature and conductivity sensors that are used for measuring standard physical hydrographic parameters. Results obtained with the fiber optic fluorometer system during a mapping study in San Diego Bay show good correlation with GC-MS analysis of total polycyclic aromatic hydrocarbons (PAHs) measured on discrete samples collected during the study.

  10. Real time synchrotron x-ray diffraction measurements to determine material strength of shocked single crystals following compression and release

    SciTech Connect

    Turneaure, Stefan J.; Gupta, Y.M.

    2009-09-15

    We present a method to use real time, synchrotron x-ray diffraction measurements to determine the strength of shocked single crystals following compression and release during uniaxial strain loading. Aluminum and copper single crystals shocked along [111] were examined to peak stresses ranging from 2 to 6 GPa. Synchrotron x rays were used to probe the longitudinal lattice strains near the rear free surface (16 and 5 {micro}m depths for Al and Cu, respectively) of the metal crystals following shock compression and release. The 111 diffraction peaks showed broadening indicating a heterogeneous microstructure in the released state. The diffraction peaks also shifted to lower Bragg angles relative to the ambient Bragg angle; the magnitude of the shift increased with increasing impact stress. The Bragg angle shifts and appropriate averaging procedures were used to determine the macroscopic or continuum strength following compression and release. For both crystals, the strengths upon release increased with increasing impact stress and provide a quantitative measure of the strain hardening that occurs in Al(111) and Cu(111) during the shock and release process. Our results for Al(111) are in reasonable agreement with a previous determination based solely on continuum measurements. Two points are noteworthy about the developments presented here: Synchrotron x rays are needed because they provide the resolution required for analyzing the data in the released state; the method presented here can be extended to the shocked state but will require additional measurements.

  11. Development of a methodology to measure the effect of ergot alkaloids on forestomach motility using real-time wireless telemetry

    NASA Astrophysics Data System (ADS)

    Egert, Amanda; Klotz, James; McLeod, Kyle; Harmon, David

    2014-10-01

    The objectives of these experiments were to characterize rumen motility patterns of cattle fed once daily using a real-time wireless telemetry system, determine when to measure rumen motility with this system, and determine the effect of ruminal dosing of ergot alkaloids on rumen motility. Ruminally cannulated Holstein steers (n = 8) were fed a basal diet of alfalfa cubes once daily. Rumen motility was measured by monitoring real-time pressure changes within the rumen using wireless telemetry and pressure transducers. Experiment 1 consisted of three 24-h rumen pressure collections beginning immediately after feeding. Data were recorded, stored, and analyzed using iox2 software and the rhythmic analyzer. All motility variables differed (P < 0.01) between hours and thirds (8-h periods) of the day. There were no differences between days for most variables. The variance of the second 8-h period of the day was less than (P < 0.01) the first for area and less than the third for amplitude, frequency, duration, and area (P < 0.05). These data demonstrated that the second 8-h period of the day was the least variable for many measures of motility and would provide the best opportunity for testing differences in motility due to treatments. In Exp. 2, the steers (n = 8) were pair-fed the basal diet of Exp. 1 and dosed with endophyte-free (E-) or endophyte-infected (E+; 0 or 10 μg ergovaline + ergovalinine / kg BW; respectively) tall fescue seed before feeding for 15 d. Rumen motility was measured for 8 h beginning 8 h after feeding for the first 14 d of seed dosing. Blood samples were taken on d 1, 7, and 15, and rumen content samples were taken on d 15. Baseline (P = 0.06) and peak (P = 0.04) pressure were lower for E+ steers. Water intake tended (P = 0.10) to be less for E+ steers the first 8 hour period after feeding. The E+ seed treatment at this dosage under thermoneutral conditions did not significantly affect rumen motility, ruminal fill, or dry matter of rumen

  12. Development of a methodology to measure the effect of ergot alkaloids on forestomach motility using real-time wireless telemetry

    PubMed Central

    Egert, Amanda M.; Klotz, James L.; McLeod, Kyle R.; Harmon, David L.

    2014-01-01

    The objectives of these experiments were to characterize rumen motility patterns of cattle fed once daily using a real-time wireless telemetry system, determine when to measure rumen motility with this system, and determine the effect of ruminal dosing of ergot alkaloids on rumen motility. Ruminally cannulated Holstein steers (n = 8) were fed a basal diet of alfalfa cubes once daily. Rumen motility was measured by monitoring real-time pressure changes within the rumen using wireless telemetry and pressure transducers. Experiment 1 consisted of three 24-h rumen pressure collections beginning immediately after feeding. Data were recorded, stored, and analyzed using iox2 software and the rhythmic analyzer. All motility variables differed (P < 0.01) between hours and thirds (8-h periods) of the day. There were no differences between days for most variables. The variance of the second 8-h period of the day was less than (P < 0.01) the first for area and less than the third for amplitude, frequency, duration, and area (P < 0.05). These data demonstrated that the second 8-h period of the day was the least variable for many measures of motility and would provide the best opportunity for testing differences in motility due to treatments. In Experiment 2, the steers (n = 8) were pair-fed the basal diet of Experiment 1 and dosed with endophyte-free (E−) or endophyte-infected (E+; 0 or 10 μg ergovaline + ergovalinine/kg BW; respectively) tall fescue seed before feeding for 15 d. Rumen motility was measured for 8 h beginning 8 h after feeding for the first 14 d of seed dosing. Blood samples were taken on d 1, 7, and 15, and rumen content samples were taken on d 15. Baseline (P = 0.06) and peak (P = 0.04) pressure were lower for E+ steers. Water intake tended (P = 0.10) to be less for E+ steers the first 8 h period after feeding. The E+ seed treatment at this dosage under thermoneutral conditions did not significantly affect rumen motility, ruminal fill, or dry matter of

  13. Multi-site magnetotelluric measurement system with real-time data analysis. Final technical report No. 210

    SciTech Connect

    Becker, J.D.; Bostick, F.X. Jr.; Smith, H.W.

    1981-09-01

    A magnetotelluric measurement system has been designed to provide a more cost effective electrical method for geothermal and mineral exploration. The theoretical requirements and sensitivities of the magnetotelluric inversion process were specifically addressed in determining system performance requirements. Significantly reduced instrument noise levels provide improved data quality, and simultaneous measurement at up to six locations provides reduced cost per site. Remotely located, battery powered, instrumentation packages return data to a central controlling site through a 2560 baud wire-line or radio link. Each remote package contains preamplifiers, data conditioning filters, and a 12-bit gain ranging A-D converter for frequencies from 0.001 Hz to 8 Hz. Data frequencies above 8 Hz are processed sequentially by a heterodyne receiver to reduce bandwidth to within the limits of the 2560 baud data link. The central data collection site provides overall control for the entire system. The system operator interacts with the system through a CRT terminal, and he receives hard copy from a matrix graphics printer. Data from the remote packages may be recorded in time sequence on a magnetic tape cartridge system, or an optional Hewlett-Packard 21MX minicomputer can be used to perform real-time frequency analysis. The results of this analysis provide feedback to the operator for improved evaluation of system performance and for selection of future measurement sites.

  14. Using microchip electrophoresis for real-time aerosol composition measurements: Field study results from San Gorgonio Wilderness, California

    NASA Astrophysics Data System (ADS)

    Evanoski-Cole, A. R.; Hecobian, A.; Lewis, G. S.; Hering, S. V.; Henry, C. S.; Collett, J. L.

    2012-12-01

    The detrimental impacts of atmospheric aerosol on human and ecosystem health, visibility and climate change have been studied extensively. However, the role of aerosol composition in these issues still needs further investigation due to the variability of aerosol particles over both time and space. The need for better temporal and spatial resolution of aerosol composition measurements is addressed in the development of a real-time instrument using microchip capillary electrophoresis. Termed Aerosol microChip Electrophoresis (ACE), this lab-on-a-chip instrument is inexpensive to manufacture, portable and provides sensitive real-time and semi-continuous aerosol composition measurements. A water condensation growth tube is used to enlarge water soluble aerosol particles with an aerodynamic diameter less than 2.5 μm. The aqueous sample is continuously collected by impaction into a sample reservoir on a custom designed microchip. A rapid separation of select aerosol components is achieved using microchip capillary electrophoresis coupled with conductivity detection. Here we present data from a recent field campaign in the San Gorgonio Wilderness in south western California. This unique high elevation wilderness site located to the east of the heavily populated cities of San Bernardino and Los Angeles provides a contrast of both clean background and aged urban aerosol as dictated by the meteorological conditions at the site. Ambient aerosol particles were continuously collected at a flow rate of 0.7 L/min into a liquid sample with a volume of 16.7 μL and then analyzed for sulfate, nitrate, chloride and oxalate every 48 seconds. When comparing the ambient concentrations with the meteorological conditions, the most notable trend was high nitrate and sulfate concentrations in ambient aerosol during upslope wind events, with values reaching as high as 34 and 5 μg/m3, respectively. Comparison aerosol composition measurements from filter samples and a particle

  15. A method for real-time measurement of respiratory rhythms in medaka (Oryzias latipes) using computer vision for water quality monitoring.

    PubMed

    Zheng, Hongyuan; Liu, Rong; Zhang, Rong; Hu, Yanqing

    2014-02-01

    The respiratory rhythms of Japanese medaka is considered to be an efficient indicator for monitoring water quality since they are sensitive to chemicals and can be measured directly from the movement of fish gill tissue generated by their breathe. However, few methods have been established to measure the feature of small free-swimming fish intuitively. In this article, a method is proposed to measure the influence of the pollution to the Japanese medaka's respiratory rhythms with computer vision technology in real time. In order to get the images which contains the complete gill tissue remotely and steadily, a special object container and an experiment platform are designed. With the aim of capturing Japanese medaka's respiratory rhythms in real time, a set of image processing algorithms such as the color distribution table, Support Vector Machine (SVM), adaptive boosting (Adaboost) and mathematical morphology are applied. Then, in order to verify the effectiveness and accuracy of the whole method, fourteen groups of Japanese medakas are respectively exposed to copper ions solutions with different concentrations of 0, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 mg/L for 48 h. The comparison between the human eyes observation and the above method indicates that the data obtained through the method is generally accurate. We found that the respiratory rate of Japanese medaka showed a downward trend initially when exposed in the copper ions solution, afterwards fluctuated repeatly arounding the lower rate, before death, the respiratory rate rised slowly for a while. With the increase of concentration, this trend will be more obvious. But the above phenomenon is absolutely different from that in the standard dilution water. Moreover, the two kinds of special respiratory rhythm of medakas poisoning were discovered. This method can be widely applied to study some toxic substances' effects on Japanese medaka's respiratory rhythms and to assess the degree of risk of the water

  16. NEAR-REAL-TIME MEASUREMENT OF TRACE VOLATILE ORGANIC COMPOUNDS FROM COMBUSTION PROCESSES USING AN ON-LINE GAS CHROMATOGRAPH

    EPA Science Inventory

    The U.S. EPA's current regulatory approach for combustion and incineration sources emphasizes the use of real-time continuous emission monitors (CEMs) for particulate, Metals, and volatile, semivolatile, and of nonvolatile organic compounds to monitor source emissions. Currently...

  17. Rapid adenosine release in the nucleus tractus solitarii during defence response in rats: real-time measurement in vivo

    PubMed Central

    Dale, Nicholas; Gourine, Alexander V; Llaudet, Enrique; Bulmer, David; Thomas, Teresa; Spyer, K Michael

    2002-01-01

    We have measured the release of adenosine and inosine from the dorsal surface of the brainstem and from within the nucleus tractus solitarii (NTS) during the defence response evoked by hypothalamic stimulation in the anaesthetised rat. At the surface of the brainstem, only release of inosine was detected on hypothalamic defence area stimulation. This inosine signal was greatly reduced by addition of the ecto-5′-nucleotidase inhibitor α,β-methylene ADP (200 μM), suggesting that the inosine arose from adenosine that was produced in the extracellular space by the prior release of ATP. By placing a microelectrode biosensor into the NTS under stereotaxic control we have recorded release of adenosine within this nucleus. By contrast to the brainstem surface, a fast increase in adenosine, accompanied only by a much smaller change in inosine levels, was seen following stimulation of the hypothalamic defence area. The release of adenosine following hypothalamic stimulation was mainly confined to a narrow region of the NTS some 500 μm in length around the level of the obex. Interestingly the release of adenosine was depletable: when the defence reaction was evoked at short time intervals, much less adenosine was released on the second stimulus. Our novel techniques have given unprecedented real-time measurement and localisation of adenosine release in vivo and demonstrate that adenosine is released at the right time and in sufficient quantities to contribute to the cardiovascular components of the defence reaction. PMID:12356888

  18. Real-time system for extracting and monitoring the cerebral functional component during fNIRS measurements

    NASA Astrophysics Data System (ADS)

    Yamada, Toru; Ohashi, Mitsuo; Umeyama, Shinji

    2015-12-01

    Functional near-infrared spectroscopy (fNIRS) can non-invasively detect hemodynamic changes associated with cerebral neural activation in human subjects. However, its signal is often affected by changes in the optical characteristics of tissues in the head other than brain. To conduct fNIRS measurements precisely and efficiently, the extraction and realtime monitoring of the cerebral functional component is crucial. We previously developed methods for extracting the cerebral functional component—the multidistance optode arrangement (MD) method and the hemodynamic modality separation (HMS) method. In this study, we implemented these methods in a software used with the fNIRS system OEG- 17APD (Spectratech, Japan), and realized a real-time display of the extracted results. When using this system for human subject experiments, the baselines obtained with the MD and HMS methods were highly stabilized, whereas originally, the fNIRS signal fluctuated significantly when the subject moved. Through a functional experiment with repetitive single-sided hand clasping tasks, the extracted signals showed distinctively higher reproducibility than that obtained in the conventional measurements.

  19. Real-Time, Online Automated System for Measurement of Water-Soluble Reactive Phosphate Ions in Atmospheric Particles.

    PubMed

    Violaki, Kalliopi; Fang, Ting; Mihalopoulos, Nikos; Weber, Rodney; Nenes, Athanasios

    2016-07-19

    We present a novel automated system for real-time measurements of water-soluble reactive phosphate (SRP) ions in atmospheric particles. Detection of SRP is based on molybdenum blue chemistry with Sn(II) chloride dihydrate reduction. The instrumentation consists of one particle-into-liquid sampler (PILS) coupled with a 250 cm path length liquid waveguide capillary cell (LWCC) and miniature fiber optic spectrometer, with detection wavelength set at 690 nm. The detection limit was 0.4 nM P, equivalent to 0.03 nmol P m(-3) in atmospheric particles. Comparison of SRP in collocate PM2.5 aerosol filter sampling with the PILS-LWCC on line system were in good agreement (n = 49, slope = 0.84, R(2) = 0.78). This novel technique offers at least an order of magnitude enhancement in sensitivity over existing approaches allowing for SRP measurements of unprecedented frequency (8 min), which will lead to greater understanding of the sources and impacts of SRP in atmospheric chemistry. PMID:27301315

  20. Carbon nanotube multi-electrode array chips for noninvasive real-time measurement of dopamine, action potentials, and postsynaptic potentials.

    PubMed

    Suzuki, Ikuro; Fukuda, Mao; Shirakawa, Keiichi; Jiko, Hideyasu; Gotoh, Masao

    2013-11-15

    Multi-electrode arrays (MEAs) can be used for noninvasive, real-time, and long-term recording of electrophysiological activity and changes in the extracellular chemical microenvironment. Neural network organization, neuronal excitability, synaptic and phenotypic plasticity, and drug responses may be monitored by MEAs, but it is still difficult to measure presynaptic activity, such as neurotransmitter release, from the presynaptic bouton. In this study, we describe the development of planar carbon nanotube (CNT)-MEA chips that can measure both the release of the neurotransmitter dopamine as well as electrophysiological responses such as field postsynaptic potentials (fPSPs) and action potentials (APs). These CNT-MEA chips were fabricated by electroplating the indium-tin oxide (ITO) microelectrode surfaces. The CNT-plated ITO electrode exhibited electrochemical response, having much higher current density compared with the bare ITO electrode. Chronoamperometric measurements using these CNT-MEA chips detected dopamine at nanomolar concentrations. By placing mouse striatal brain slices on the CNT-MEA chip, we successfully measured synaptic dopamine release from spontaneous firings with a high S/N ratio of 62. Furthermore, APs and fPSPs were measured from cultured hippocampal neurons and slices with high temporal resolution and a 100-fold greater S/N ratio. Our CNT-MEA chips made it possible to measure neurotransmitter dopamine (presynaptic activities), postsynaptic potentials, and action potentials, which have a central role in information processing in the neuronal network. CNT-MEA chips could prove useful for in vitro studies of stem cell differentiation, drug screening and toxicity, synaptic plasticity, and pathogenic processes involved in epilepsy, stroke, and neurodegenerative diseases. PMID:23774164

  1. CoWS: Continuous Water Sampler for CRDS-based, real-time measurements of water isotopes

    NASA Astrophysics Data System (ADS)

    Carter, J.; Huang, K.; Dennis, K. J.

    2014-12-01

    Stable isotopes of water (δ18O and δD) are unique tracers for studying hydrological and associated processes. High spatial and temporal resolution measurements of water isotopes are necessary to follow the dynamics in rapidly changing systems and to map out the spatial heterogeneity of water circulation and mixing. Here we present results of the first commercially available Continuous Water Sampler Module (CoWS) that can be coupled to a Picarro L2130-i Cavity Ring-Down Spectrometer (CRDS) for real-time measurements of water isotopes. The CoWS is a compact and fully automated system with its core method modified from that of Munksgaard et al. (2011). Liquid water is continuously pumped into an extraction chamber, where water vapor diffuses through a micro-poruous polytetrafluoroethylene (ePTFE) membrane. The vapor is then carried by a dry carrier gas to the L2130-i for high precision measurements of δ18O and δD. The inlet water, carrier gas, and surface of the ePTFE membrane are actively temperature controlled to maintain a stable amount of fractionation of water isotopes across the membrane, which minimizes measurement drift. We have tested the CoWS-CRDS system with various inlet water types (tap water, deionized water, and seawater), and under operational conditions with variable ambient water and air temperatures. CoWS-CRDS has high precision (< 0.05 and < 0.15 ‰ 1σ, 5 minute average for δ18O and δD, respectively) and low drift water isotope measurements, with short response time (<5 minutes to eliminate 98% of the memory). The CoWS software is user configurable; allowing automated sampling among up to four water sources with user defined sampling durations. Additionally, we will present isotopic measurements with high-temporal resolution of an estuarine system where tidal changes affected the isotopic composition of the estuary.

  2. Slim hole MWD tool accurately measures downhole annular pressure

    SciTech Connect

    Burban, B.; Delahaye, T. )

    1994-02-14

    Measurement-while-drilling of downhole pressure accurately determines annular pressure losses from circulation and drillstring rotation and helps monitor swab and surge pressures during tripping. In early 1993, two slim-hole wells (3.4 in. and 3 in. diameter) were drilled with continuous real-time electromagnetic wave transmission of downhole temperature and annular pressure. The data were obtained during all stages of the drilling operation and proved useful for operations personnel. The use of real-time measurements demonstrated the characteristic hydraulic effects of pressure surges induced by drillstring rotation in the small slim-hole annulus under field conditions. The interest in this information is not restricted to the slim-hole geometry. Monitoring or estimating downhole pressure is a key element for drilling operations. Except in special cases, no real-time measurements of downhole annular pressure during drilling and tripping have been used on an operational basis. The hydraulic effects are significant in conventional-geometry wells (3 1/2-in. drill pipe in a 6-in. hole). This paper describes the tool and the results from the field test.

  3. Development and Evaluation of a Test for Tuberculosis in Live European Badgers (Meles meles) Based on Measurement of Gamma Interferon mRNA by Real-Time PCR▿

    PubMed Central

    Sawyer, J.; Mealing, D.; Dalley, D.; Davé, D.; Lesellier, S.; Palmer, S.; Bowen-Davies, J.; Crawshaw, T. R.; Chambers, M. A.

    2007-01-01

    A real-time PCR assay for the measurement of gamma interferon (IFN-γ) mRNA in European badger (Meles meles) blood cultures was developed. The levels of IFN-γ mRNA in blood cultures stimulated with either bovine or avian tuberculin or specific mycobacterial antigens were compared with those in a nonstimulated control blood culture as the basis for determining the tuberculosis (TB) status of live badgers. The assay was validated by testing 247 animals for which there were matching data from postmortem examination and culture of tissues. Relative changes in the levels of IFN-γ mRNA in response to bovine tuberculin and specific antigens were found to be greater among badgers with tissues positive for TB on culture. The test was at its most accurate (87% of test results were correct) by using blood cultures containing bovine tuberculin as the antigen and when the response to avian tuberculin was taken into account by subtracting the avian tuberculin response from the bovine tuberculin response. At a specificity of 90.7%, the test was 70.6% sensitive. At the same specificity, the current serological enzyme-linked immunosorbent assay for TB in badgers was only 53% sensitive. This work demonstrates that measurement of IFN-γ mRNA by real-time PCR is a valid method for the detection of TB in live badgers and may provide an alternative to the current serological methods of diagnosis, the Brock test. The testing procedure can be completed within 5 h of receipt of the blood culture samples. In addition, the use of a molecular biology-based test offers the potential to fully automate the testing procedure through the use of robotics. PMID:17537931

  4. Design and Validation of a Compressive Tissue Stimulator with High-Throughput Capacity and Real-Time Modulus Measurement Capability

    PubMed Central

    Salvetti, David J.; Pino, Christopher J.; Manuel, Steven G.; Dallmeyer, Ian; Rangarajan, Sanjeet V.; Meyer, Tobias; Kotov, Misha

    2012-01-01

    Mechanical stimulation has been shown to impact the properties of engineered hyaline cartilage constructs and is relevant for engineering of cartilage and osteochondral tissues. Most mechanical stimulators developed to date emphasize precision over adaptability to standard tissue culture equipment and protocols. The realization of mechanical characteristics in engineered constructs approaching native cartilage requires the optimization of complex variables (type of stimulus, regimen, and bimolecular signals). We have proposed and validated a stimulator design that focuses on high construct capacity, compatibility with tissue culture plastic ware, and regimen adaptability to maximize throughput. This design utilizes thin force sensors in lieu of a load cell and a linear encoder to verify position. The implementation of an individual force sensor for each sample enables the measurement of Young's modulus while stimulating the sample. Removable and interchangeable Teflon plungers mounted using neodymium magnets contact each sample. Variations in plunger height and design can vary the strain and force type on individual samples. This allows for the evaluation of a myriad of culture conditions and regimens simultaneously. The system was validated using contact accuracy, and Young's modulus measurements range as key parameters. Contact accuracy for the system was excellent within 1.16% error of the construct height in comparison to measurements made with a micrometer. Biomaterials ranging from bioceramics (cancellous bone, 123 MPa) to soft gels (1% agarose, 20 KPa) can be measured without any modification to the device. The accuracy of measurements in conjunction with the wide range of moduli tested demonstrate the unique characteristics of the device and the feasibility of using this device in mapping real-time changes to Young's modulus of tissue constructs (cartilage, bone) through the developmental phases in ex vivo culture conditions. PMID:21988089

  5. Design and validation of a compressive tissue stimulator with high-throughput capacity and real-time modulus measurement capability.

    PubMed

    Salvetti, David J; Pino, Christopher J; Manuel, Steven G; Dallmeyer, Ian; Rangarajan, Sanjeet V; Meyer, Tobias; Kotov, Misha; Shastri, V Prasad

    2012-03-01

    Mechanical stimulation has been shown to impact the properties of engineered hyaline cartilage constructs and is relevant for engineering of cartilage and osteochondral tissues. Most mechanical stimulators developed to date emphasize precision over adaptability to standard tissue culture equipment and protocols. The realization of mechanical characteristics in engineered constructs approaching native cartilage requires the optimization of complex variables (type of stimulus, regimen, and bimolecular signals). We have proposed and validated a stimulator design that focuses on high construct capacity, compatibility with tissue culture plastic ware, and regimen adaptability to maximize throughput. This design utilizes thin force sensors in lieu of a load cell and a linear encoder to verify position. The implementation of an individual force sensor for each sample enables the measurement of Young's modulus while stimulating the sample. Removable and interchangeable Teflon plungers mounted using neodymium magnets contact each sample. Variations in plunger height and design can vary the strain and force type on individual samples. This allows for the evaluation of a myriad of culture conditions and regimens simultaneously. The system was validated using contact accuracy, and Young's modulus measurements range as key parameters. Contact accuracy for the system was excellent within 1.16% error of the construct height in comparison to measurements made with a micrometer. Biomaterials ranging from bioceramics (cancellous bone, 123 MPa) to soft gels (1% agarose, 20 KPa) can be measured without any modification to the device. The accuracy of measurements in conjunction with the wide range of moduli tested demonstrate the unique characteristics of the device and the feasibility of using this device in mapping real-time changes to Young's modulus of tissue constructs (cartilage, bone) through the developmental phases in ex vivo culture conditions. PMID:21988089

  6. Combined analysis of soil moisture measurements from roving and fixed cosmic ray neutron probes for multiscale real-time monitoring

    NASA Astrophysics Data System (ADS)

    Franz, Trenton E.; Wang, Tiejun; Avery, William; Finkenbiner, Catherine; Brocca, Luca

    2015-05-01

    Soil moisture partly controls land-atmosphere mass and energy exchanges and ecohydrological processes in natural and agricultural systems. Thus, many models and remote sensing products continue to improve their spatiotemporal resolution of soil moisture, with some land surface models reaching 1 km resolution. However, the reliability and accuracy of both modeled and remotely sensed soil moisture require comparison with ground measurements at the appropriate spatiotemporal scales. One promising technique is the cosmic ray neutron probe. Here we further assess the suitability of this technique for real-time monitoring across a large area by combining data from three fixed probes and roving surveys over a 12 km × 12 km area in eastern Nebraska. Regression analyses indicated linear relationships between the fixed probe averages and roving estimates of soil moisture for each grid cell, allowing us to derive an 8 h product at spatial resolutions of 1, 3, and 12 km, with root-mean-square error of 3%, 1.8%, and 0.9%.

  7. Development of In-Situ Erosion Measurement Techniques for Application to Real-Time Determination of Plasma Thruster Component Lifetimes

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This research has resulted in advancing the laser-based diagnostic capability and the ion optics development in the ion propulsion program at NASA GRC. Laser-based plasma diagnostics have been demonstrated in tabletop experiments and, in the case of LDI, on laboratory hollow cathodes. Assessment by GRC of its resources and priorities two years into the grant lead to a refocusing of the research effort away from the development of a real-time erosion rate measurement technique. The extension of the diagnostic techniques to diagnostic tools has been transferred to graduate students under the technical direction of the PI. These diagnostics may facilitate the development of ion thruster with significantly improved throughput capability for lower-power (10 kW) missions High-Isp, Long-lived ion optics development has proceeded from simple extensions of state-of-the-art geometries to radically different geometries and materials. Full-scale testing of these ion optics has demonstrated a significant advance in the throughput capability of ion thrusters enabling significantly more demanding missions. The capability to predict the throughput was developed and will continue to be upgraded. The performance models have been validated via full-scale testing. Partial validation of the throughput prediction will be completed via an upcoming wear test of the ion optics.

  8. NAP1-Assisted Nucleosome Assembly on DNA Measured in Real Time by Single-Molecule Magnetic Tweezers

    PubMed Central

    Vlijm, Rifka; Smitshuijzen, Jeremy S. J.; Lusser, Alexandra; Dekker, Cees

    2012-01-01

    While many proteins are involved in the assembly and (re)positioning of nucleosomes, the dynamics of protein-assisted nucleosome formation are not well understood. We study NAP1 (nucleosome assembly protein 1) assisted nucleosome formation at the single-molecule level using magnetic tweezers. This method allows to apply a well-defined stretching force and supercoiling density to a single DNA molecule, and to study in real time the change in linking number, stiffness and length of the DNA during nucleosome formation. We observe a decrease in end-to-end length when NAP1 and core histones (CH) are added to the dsDNA. We characterize the formation of complete nucleosomes by measuring the change in linking number of DNA, which is induced by the NAP1-assisted nucleosome assembly, and which does not occur for non-nucleosomal bound histones H3 and H4. By rotating the magnets, the supercoils formed upon nucleosome assembly are removed and the number of assembled nucleosomes can be counted. We find that the compaction of DNA at low force is about 56 nm per assembled nucleosome. The number of compaction steps and associated change in linking number indicate that NAP1-assisted nucleosome assembly is a two-step process. PMID:23050009

  9. Insights Into Ice Nucleation From Real-Time, Single-Particle Aircraft-Based Measurements of Ice Crystal Residues

    NASA Astrophysics Data System (ADS)

    Pratt, K. A.; Demott, P. J.; Twohy, C. H.; Prather, K. A.

    2008-12-01

    The overall impacts of aerosol particles on cloud formation and properties represent the largest single source of uncertainty in predicting future climate change. In particular, the ability of aerosols to act as ice nuclei (IN) has large consequences on the hydrological cycle since much precipitation derives from the ice phase. During the flight-based 2007 Ice in Clouds Experiment - Layer Clouds (ICE-L) on the NSF/NCAR C- 130, individual cloud droplets and ice crystals were directly sampled and characterized in real-time using a counterflow virtual impactor (CVI) in series with the aircraft aerosol time-of-flight mass spectrometer (A- ATOFMS) and continuous-flow diffusion chamber (CFDC). Parallel measurements by the A-ATOFMS and CFDC allowed the size-resolved chemistry of cloud residues, including both refractory and non-refractory species, to be examined and correlated with the ice nucleation properties of the clouds. Through comparison with cloud probes, the mixing state of liquid, mixed, and ice phase residues were examined separately. During the study, orographic wave clouds were sampled over Wyoming; mineral dust, biological material, biomass burning particles, soot, and organic carbon were all found within the studied clouds. A comparison of the aerosol chemistry associated with periods of differing quantities of ice nuclei present are being examined to further increase our understanding of ice nucleation relation to aerosol composition.

  10. New Approach for Near-Real-Time Measurement of Elemental Composition of Aerosol Using Laser-Induced Breakdown Spectroscopy

    PubMed Central

    Diwakar, Prasoon; Kulkarni, Pramod; Birch, M. Eileen

    2015-01-01

    A new approach has been developed for making near-real-time measurement of elemental composition of aerosols using plasma spectroscopy. The method allows preconcentration of miniscule particle mass (pg to ng) directly from the sampled aerosol stream through electrostatic deposition of charged particles (30–900 nm) onto a flat-tip microneedle electrode. The collected material is subsequently ablated from the electrode and monitored by laser-induced breakdown spectroscopy. Atomic emission spectra were collected using a broadband spectrometer with a wavelength range of 200–980 nm. A single-sensor delay time of 1.3 μs was used in the spectrometer for all elements to allow simultaneous measurement of multiple elements. The system was calibrated for various elements including Cd, Cr, Cu, Mn, Na, and Ti. The absolute mass detection limits for these elements were experimentally determined and found to be in the range of 0.018–5 ng. The electrostatic collection technique has many advantages over other substrate-based methods involving aerosol collection on a filter or its focused deposition using an aerodynamic lens. Because the particle mass is collected over a very small area that is smaller than the spatial extent of the laser-induced plasma, the entire mass is available for analysis. This considerably improves reliability of the calibration and enhances measurement accuracy and precision. Further, the aerosol collection technique involves very low pressure drop, thereby allowing higher sample flow rates with much smaller pumps—a desirable feature for portable instrumentation. Higher flow rates also make it feasible to measure trace element concentrations at part per trillion levels. Detection limits in the range of 18–670 ng m−3 can be achieved for most of the elements studied at a flow rate of 1.5 L min−1 with sampling times of 5 min. PMID:26692632

  11. Influence of storage time on DNA of Chlamydia trachomatis, Ureaplasma urealyticum, and Neisseria gonorrhoeae for accurate detection by quantitative real-time polymerase chain reaction.

    PubMed

    Lu, Y; Rong, C Z; Zhao, J Y; Lao, X J; Xie, L; Li, S; Qin, X

    2016-01-01

    The shipment and storage conditions of clinical samples pose a major challenge to the detection accuracy of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Ureaplasma urealyticum (UU) when using quantitative real-time polymerase chain reaction (qRT-PCR). The aim of the present study was to explore the influence of storage time at 4°C on the DNA of these pathogens and its effect on their detection by qRT-PCR. CT, NG, and UU positive genital swabs from 70 patients were collected, and DNA of all samples were extracted and divided into eight aliquots. One aliquot was immediately analyzed with qRT-PCR to assess the initial pathogen load, whereas the remaining samples were stored at 4°C and analyzed after 1, 2, 3, 7, 14, 21, and 28 days. No significant differences in CT, NG, and UU DNA loads were observed between baseline (day 0) and the subsequent time points (days 1, 2, 3, 7, 14, 21, and 28) in any of the 70 samples. Although a slight increase in DNA levels was observed at day 28 compared to day 0, paired sample t-test results revealed no significant differences between the mean DNA levels at different time points following storage at 4°C (all P>0.05). Overall, the CT, UU, and NG DNA loads from all genital swab samples were stable at 4°C over a 28-day period. PMID:27580005

  12. Influence of storage time on DNA of Chlamydia trachomatis, Ureaplasma urealyticum, and Neisseria gonorrhoeae for accurate detection by quantitative real-time polymerase chain reaction

    PubMed Central

    Lu, Y.; Rong, C.Z.; Zhao, J.Y.; Lao, X.J.; Xie, L.; Li, S.; Qin, X.

    2016-01-01

    The shipment and storage conditions of clinical samples pose a major challenge to the detection accuracy of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Ureaplasma urealyticum (UU) when using quantitative real-time polymerase chain reaction (qRT-PCR). The aim of the present study was to explore the influence of storage time at 4°C on the DNA of these pathogens and its effect on their detection by qRT-PCR. CT, NG, and UU positive genital swabs from 70 patients were collected, and DNA of all samples were extracted and divided into eight aliquots. One aliquot was immediately analyzed with qRT-PCR to assess the initial pathogen load, whereas the remaining samples were stored at 4°C and analyzed after 1, 2, 3, 7, 14, 21, and 28 days. No significant differences in CT, NG, and UU DNA loads were observed between baseline (day 0) and the subsequent time points (days 1, 2, 3, 7, 14, 21, and 28) in any of the 70 samples. Although a slight increase in DNA levels was observed at day 28 compared to day 0, paired sample t-test results revealed no significant differences between the mean DNA levels at different time points following storage at 4°C (all P>0.05). Overall, the CT, UU, and NG DNA loads from all genital swab samples were stable at 4°C over a 28-day period. PMID:27580005

  13. Accurate Detection and Quantification of the Fish Viral Hemorrhagic Septicemia virus (VHSv) with a Two-Color Fluorometric Real-Time PCR Assay

    PubMed Central

    Palsule, Vrushalee V.; Yeo, Jiyoun; Shepherd, Brian S.; Crawford, Erin L.; Stepien, Carol A.

    2013-01-01

    Viral Hemorrhagic Septicemia virus (VHSv) is one of the world's most serious fish pathogens, infecting >80 marine, freshwater, and estuarine fish species from Eurasia and North America. A novel and especially virulent strain – IVb – appeared in the Great Lakes in 2003, has killed many game fish species in a series of outbreaks in subsequent years, and shut down interstate transport of baitfish. Cell culture is the diagnostic method approved by the USDA-APHIS, which takes a month or longer, lacks sensitivity, and does not quantify the amount of virus. We thus present a novel, easy, rapid, and highly sensitive real-time quantitative reverse transcription PCR (qRT-PCR) assay that incorporates synthetic competitive template internal standards for quality control to circumvent false negative results. Results demonstrate high signal-to-analyte response (slope = 1.00±0.02) and a linear dynamic range that spans seven orders of magnitude (R2 = 0.99), ranging from 6 to 6,000,000 molecules. Infected fishes are found to harbor levels of virus that range to 1,200,000 VHSv molecules/106 actb1 molecules with 1,000 being a rough cut-off for clinical signs of disease. This new assay is rapid, inexpensive, and has significantly greater accuracy than other published qRT-PCR tests and traditional cell culture diagnostics. PMID:23977162

  14. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  15. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  16. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  17. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  18. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  19. MISR Level 1 Near Real Time Products

    Atmospheric Science Data Center

    2014-09-15

    Level 1 Near Real Time The MISR Near Real Time Level 1 data products consist of radiance measurements organized in 10-50 minute ... (off-nadir) cameras. The remaining channels are sampled at 1.1 km. ...

  20. Real-time, high-resolution quantitative measurement of multiple soil gas emissions: selected ion flow tube mass spectrometry.

    PubMed

    Milligan, D B; Wilson, P F; Mautner, M N; Freeman, C G; McEwan, M J; Clough, T J; Sherlock, R R

    2002-01-01

    A new technique is presented for the rapid, high-resolution identification and quantification of multiple trace gases above soils, at concentrations down to 0.01 microL L(-1) (10 ppb). The technique, selected ion flow tube mass spectrometry (SIFT-MS), utilizes chemical ionization reagent ions that react with trace gases but not with the major air components (N2, O2, Ar, CO2). This allows the real-time measurement of multiple trace gases without the need for preconcentration, trapping, or chromatographic separation. The technique is demonstrated by monitoring the emission of ammonia and nitric oxide, and the search for volatile organics, above containerized soil samples treated with synthetic cattle urine. In this model system, NH3 emissions peaked after 24 h at 2000 nmol m(-2) s(-1) and integrated to approximately 7% of the urea N applied, while NO emissions peaked about 25 d after urine addition at approximately 140 nmol m(-2) s(-1) and integrated to approximately 10% of the applied urea N. The monitoring of organics along with NH3 and NO was demonstrated in soils treated with synthetic urine, pyridine, and dimethylamine. No emission of volatile nitrogen organics from the urine treatments was observed at levels >0.01% of the applied nitrogen. The SIFT method allows the simultaneous in situ measurement of multiple gas components with a high spatial resolution of < 10 cm and time resolution <20 s. These capabilities allow, for example, identification of emission hotspots, and measurement of localized and rapid variations above agricultural and contaminated soils, as well as integrated emissions over longer periods. PMID:11931442

  1. Real-time measurements of chemical and isotope composition of atmospheric and volcanic CO2 at Mt. Etna (Italy)

    NASA Astrophysics Data System (ADS)

    Rizzo, Andrea L.; Jost, Hans-Jürg; Caracausi, Antonio; Paonita, Antonio; Liotta, Marcello; Martelli, Mauro

    2014-05-01

    We present unprecedented data of real-time measurements of chemical and isotope (δ13C) composition of CO2 in air and in fumarolic-plume gases collected at Mt. Etna volcano. Two campaigns of measurements were performed on 11 July and on 5-6 September 2013, by using a Delta Ray tunable diode laser. With the assumption of a two components mixing, a simple linear regression was applied to the data in order to obtain the volcanogenic δ13C. Data acquired along the route Catania-Etna, while car was moving, showed an excess of 13C-depleted CO2 when passing through inhabited centers due to atmospheric pollution produced by the cars exhaust. Fumaroles of Torre del Filosofo (2,900 m a.s.l.) displayed a δ13C between -3.2±0.03o and -3.7±0.05o comparable to IRMS measurements of discrete samples collected in the same date and in previous investigations. Diluted plume gases were collected at more than 1 km from the craters and showed δ13C=-2.2±0.2o accordingly with collected crater fumaroles. Considering the huge amount of data that may be acquired in a very short time by Delta Ray, we demonstrate that the addition to the atmospheric CO2 content of ~100 ppm of CO2 from an unknown source is enough to allow a mathematical calculation of the end-member with an uncertainty generally < 0.15‰This is feasible with the assumption of a binary mixing. We thus infer that the application performed at Mt. Etna may represent an historical step forward for the scientific community in volcanic surveillance.

  2. Real-time monitoring and measurement of wax deposition in pipelines via non-invasive electrical capacitance tomography

    NASA Astrophysics Data System (ADS)

    Lock Sow Mei, Irene; Ismail, Idris; Shafquet, Areeba; Abdullah, Bawadi

    2016-02-01

    Tomographic analysis of the behavior of waxy crude oil in pipelines is important to permit appropriate corrective actions to be taken to remediate the wax deposit layer before pipelines are entirely plugged. In this study, a non-invasive/non-intrusive electrical capacitance tomography (ECT) system has been applied to provide real-time visualization of the formation of paraffin waxes and to measure the amount of wax fraction from the Malay Basin waxy crude oil sample under the static condition. Analogous expressions to estimate the wax fraction of the waxy crude oil across the temperatures range of 30-50 °C was obtained by using Otsu’s and Kuo’s threshold algorithms. Otsu’s method suggested that the wax fraction can be estimated by the correlation coefficient β =0.0459{{T}3}-5.3535{{T}2}+200.36T-2353.7 while Kuo’s method provides a similar correlation with β =0.0741{{T}3}-8.4915{{T}2}+314.96T-3721.2 . These correlations show good agreements with the results which are obtained from the conventional weighting method. This study suggested that Kuo’s threshold algorithm is more promising when integrated into the ECT system compared to Otsu’s algorithm because the former provides higher accuracy wax fraction measurement results below the wax appearance temperature for waxy crude oil. This study is significant because it serves as a preliminary investigation for the application of ECT in the oil and gas industry for online measurement and detection of wax fraction without causing disturbance to the process flow.

  3. Real time polarimetric dehazing.

    PubMed

    Mudge, Jason; Virgen, Miguel

    2013-03-20

    Remote sensing is a rich topic due to its utility in gathering detailed accurate information from locations that are not economically feasible traveling destinations or are physically inaccessible. However, poor visibility over long path lengths is problematic for a variety of reasons. Haze induced by light scatter is one cause for poor visibility and is the focus of this article. Image haze comes about as a result of light scattering off particles and into the imaging path causing a haziness to appear on the image. Image processing using polarimetric information of light scatter can be used to mitigate image haze. An imaging polarimeter which provides the Stokes values in real time combined with a "dehazing" algorithm can automate image haze removal for instant applications. Example uses are to improve visual display providing on-the-spot detection or imbedding in an active control loop to improve viewing and tracking while on a moving platform. In addition, removing haze in this manner allows the trade space for a system operational waveband to be opened up to bands which are object matched and not necessarily restricted by scatter effects. PMID:23518739

  4. Laser Capture Microdissection and Real-Time PCR for Measuring mRNA in Giant Cells Induced by Meloidogyne javanica.

    PubMed

    He, Bin; Magill, C; Starr, J L

    2005-09-01

    The techniques of laser capture microdissection and quantitative RT-PCR were investigated as methods for measuring mRNA in giant cells induced by Meloidogyne javanica. Laser capture microdissection allowed precise sampling of giant cells at 1 to 3 weeks after inoculation. The expression of three genes (a water channel protein gene Rb7, a plasma membrane H(+)-ATPase (LHA4), and a hexose kinase (HXK1) was measured based on mRNA extracted from tissue samples and quantitated using reversetranscription real-time PCR. These genes were chosen arbitrarily to represent different aspects of primary metabolism. The amount of HXK1 mRNA in giant cells was not different from that in root meristem or cortical cells when compared on the basis of number of molecules per unit tissue volume, and was similar at all sample times. Amount of mRNA for LHA4 and Rb7 was much greater in giant cells than in cortical cells, but only Rb7 was also greater in giant cells than in root meristem cells. Numbers of mRNA molecules of LHA4 increased linearly in giant cells from 1 to 3 weeks after inoculation, whereas the amount of Rb7 mRNA was similar at 1 and 2 weeks after inoculation but increased at 3 weeks after inoculation. The amount of mRNA for these two genes was similar at all sample times in cortical and root-tip cells. Apparent up regulation of some genes in giant cells may be due primarily to the increased number of copies of the gene in giant cells, whereas for other genes up regulation may also involve increased transcription of the increased number of copies of the gene. PMID:19262878

  5. Relative indexes of cutaneous blood perfusion measured by real-time laser Doppler imaging (LDI) in healthy volunteers.

    PubMed

    Seyed Jafari, S Morteza; Schawkat, Megir; Van De Ville, Dimitri; Shafighi, Maziar

    2014-07-01

    We used real-time LDI to study regional variations in microcirculatory perfusion in healthy candidates to establish a new methodology for global perfusion body mapping that is based on intra-individual perfusion index ratios. Our study included 74 (37 female) healthy volunteers aged between 22 and 30 years (mean 24.49). Imaging was performed using a recent microcirculation-imaging camera (EasyLDI) for different body regions of each volunteer. The perfusion values were reported in Arbitrary Perfusion Units (APU). The relative perfusion indexes for each candidate's body region were then obtained by normalization with the perfusion value of the forehead. Basic parameters such as weight, height, and blood pressure were also measured and analyzed. The highest mean perfusion value was reported in the forehead area (259.21APU). Mean perfusion in the measured parts of the body correlated positively with mean forehead value, while there was no significant correlation between forehead blood perfusion values and room temperature, BMI, systolic blood pressure and diastolic blood pressure (p=0.420, 0.623, 0.488, 0.099, respectively). Analysis of the data showed that perfusion indexes were not significantly different between male and female volunteers except for the ventral upper arm area (p=.001). LDI is a non-invasive, fast technique that opens several avenues for clinical applications. The mean perfusion indexes are useful in clinical practice for monitoring patients before and after surgical interventions. Perfusion values can be predicted for different body parts for patients only by taking the forehead perfusion value and using the perfusion index ratios to obtain expected normative perfusion values. PMID:24788075

  6. Real-time measurements of levoglucosan in fine aerosols (PM2.5) in the region of Paris (France)

    NASA Astrophysics Data System (ADS)

    Sciare, J.; Bonnaire, N.; Mocnik, G.; Nicolas, J.; Petit, J. E.; Bressi, M.; Sarda-Estève, R.; Drinovic, L.

    2012-04-01

    Levoglucosan - one the major monosaccharide anhydride compounds produced by the combustion of cellulose and hemicellulose - is emitted in large amounts by wildfires or residential wood burning (during winter months). Over the past few years, this specific tracer has received more and more attention at it can be used in a quantitative way to derive atmospheric concentrations of biomass burning aerosols [Favez et al., 2010] which aerosol source has strong implications for climate and air quality studies. A new technique has been developed and is presented here to investigate real-time concentrations of levoglucosan in fine aerosols (PM2.5). This technique is based on a Particle-into-liquid-sampler (PILS, Brechtel Manufacturing inc., model 4002) used "on-line" and coupled with an electrospray ionisation source - tandem mass spectrometry (ESI-MS/MS, AB SCIEX model 3200 QTRAP). Air was drawn in the PILS at 15LPM and removed from particles larger than 2.5μm aerodynamic diameter (AD) using a very sharp cyclone. Water-soluble aerosols were collected in the PILS and sent in the 10μl loop of the ESI-MS/MS at a flowrate of 50μl/min. Flow injection analysis (FIA) was then performed every 2.5min for the quantification of levoglucosan using a specific transition 161-113 m/z (negative mode), by Multiple Reaction Monitoring (MRM) mode. An internal levoglucosan standard was injected every 10 samples (i.e. every 25min) in order to check the stability of the mass spectrometry calibration. Field blanks were performed using a total filter upstream of the PILS instrument and did not show any detectable amount of levoglucosan. A limit of quantification (LOQ) better than 1 ng/m3 was calculated here for levoglucosan in FIA mode. Based on these settings, unattended measurements of levoglucosan by PILS-ESI-MS/MS have been performed every 2.5 min in the region of Paris for a couple of weeks during the winter 2011 showing concentrations ranging from below 1ng/m3 to more than 500ng/m3. These

  7. Real-time in situ measurements of volcanic plume physico-chemical properties using Controlled METeorological balloons

    NASA Astrophysics Data System (ADS)

    Durant, Adam; Voss, Paul; Watson, Matthew; Roberts, Tjarda; Thomas, Helen; Prata, Fred; Sutton, Jeff; Mather, Tamsin; Witt, Melanie; Patrick, Matthew

    2010-05-01

    While the climatic effects of volcanogenic sulphate aerosol in the stratosphere are well characterised, the nature and global impact of sustained tropospheric volcanic degassing is less well understood. In situ measurement of volcanic emissions can be used to understand plume processes (e.g., microphysics and chemistry), and used to validate and improve remote sensing techniques. New developments in sensor and communication technologies have led to the production of miniaturized lightweight unmanned atmospheric measurement platforms. Controlled METeorological (CMET) balloons collect real-time observations of atmospheric physico-chemical properties at altitudes of up to 5 km for hours or even days at a time. Standard measurements include pressure (± 10 mb), aspirated temperature (± 0.3 C), relative humidity (± 5 %) and location (GPS position ± 5 m horizontal, ± 50 m vertical). Balloon platform-based measurements of volcanic plume properties were made for the first time using CMET balloons equipped with miniature electrochemical sensors during the eruption of Halema'uma'u crater (Kilauea) in Hawai'i in 2008. In addition, multiple measurement platforms were simultaneously deployed that included (1) ground-based remote measurements (mini-DOAS and UV camera); (2) satellite-based sensors (MODIS and OMI); and (3) in situ sampling at the emission source using ground-based electrochemical sensor instrumentation. During the 25 July 2008 flight, a single CMET balloon remained in the plume and collected data for several hours. Ratios of [H2O] and [SO2] correlate in proximal regions of the plume, though were found to anti-correlate further downwind. Correlation is explained through co-emission of SO2 and H2O at source, as has been frequently previously observed e.g. by FTIR. Anti-correlation of [H2O] and [SO2] ratios has not previously been reported and may reflect dehydration of the aged plume through condensation of water vapour on volcanogenic sulphate aerosol. The

  8. Leptin in Whales: Validation and Measurement of mRNA Expression by Absolute Quantitative Real-Time PCR

    PubMed Central

    Ball, Hope C.; Holmes, Robert K.; Londraville, Richard L.; Thewissen, Johannes G. M.; Duff, Robert Joel

    2013-01-01

    Leptin is the primary hormone in mammals that regulates adipose stores. Arctic adapted cetaceans maintain enormous adipose depots, suggesting possible modifications of leptin or receptor function. Determining expression of these genes is the first step to understanding the extreme physiology of these animals, and the uniqueness of these animals presents special challenges in estimating and comparing expression levels of mRNA transcripts. Here, we compare expression of two model genes, leptin and leptin-receptor gene-related product (OB-RGRP), using two quantitative real-time PCR (qPCR) methods: “relative” and “absolute”. To assess the expression of leptin and OB-RGRP in cetacean tissues, we first examined how relative expression of those genes might differ when normalized to four common endogenous control genes. We performed relative expression qPCR assays measuring the amplification of these two model target genes relative to amplification of 18S ribosomal RNA (18S), ubiquitously expressed transcript (Uxt), ribosomal protein 9 (Rs9) and ribosomal protein 15 (Rs15) endogenous controls. Results demonstrated significant differences in the expression of both genes when different control genes were employed; emphasizing a limitation of relative qPCR assays, especially in studies where differences in physiology and/or a lack of knowledge regarding levels and patterns of expression of common control genes may possibly affect data interpretation. To validate the absolute quantitative qPCR methods, we evaluated the effects of plasmid structure, the purity of the plasmid standard preparation and the influence of type of qPCR “background” material on qPCR amplification efficiencies and copy number determination of both model genes, in multiple tissues from one male bowhead whale. Results indicate that linear plasmids are more reliable than circular plasmid standards, no significant differences in copy number estimation based upon background material used, and

  9. Leptin in whales: validation and measurement of mRNA expression by absolute quantitative real-time PCR.

    PubMed

    Ball, Hope C; Holmes, Robert K; Londraville, Richard L; Thewissen, Johannes G M; Duff, Robert Joel

    2013-01-01

    Leptin is the primary hormone in mammals that regulates adipose stores. Arctic adapted cetaceans maintain enormous adipose depots, suggesting possible modifications of leptin or receptor function. Determining expression of these genes is the first step to understanding the extreme physiology of these animals, and the uniqueness of these animals presents special challenges in estimating and comparing expression levels of mRNA transcripts. Here, we compare expression of two model genes, leptin and leptin-receptor gene-related product (OB-RGRP), using two quantitative real-time PCR (qPCR) methods: "relative" and "absolute". To assess the expression of leptin and OB-RGRP in cetacean tissues, we first examined how relative expression of those genes might differ when normalized to four common endogenous control genes. We performed relative expression qPCR assays measuring the amplification of these two model target genes relative to amplification of 18S ribosomal RNA (18S), ubiquitously expressed transcript (Uxt), ribosomal protein 9 (Rs9) and ribosomal protein 15 (Rs15) endogenous controls. Results demonstrated significant differences in the expression of both genes when different control genes were employed; emphasizing a limitation of relative qPCR assays, especially in studies where differences in physiology and/or a lack of knowledge regarding levels and patterns of expression of common control genes may possibly affect data interpretation. To validate the absolute quantitative qPCR methods, we evaluated the effects of plasmid structure, the purity of the plasmid standard preparation and the influence of type of qPCR "background" material on qPCR amplification efficiencies and copy number determination of both model genes, in multiple tissues from one male bowhead whale. Results indicate that linear plasmids are more reliable than circular plasmid standards, no significant differences in copy number estimation based upon background material used, and that the use of

  10. REAL-TIME MODELING AND MEASUREMENT OF MOBILE SOURCE POLLUTANT CONCENTRATIONS FOR ESTIMATING HUMAN EXPOSURES IN COMMUNITIES NEAR ROADWAYS

    EPA Science Inventory

    The United States Environmental Protection Agency's (EPA) National Exposure Research Laboratory (NERL) is pursuing a project to improve the methodology for real-time site specific modeling of human exposure to pollutants from motor vehicles. The overall project goal is to deve...

  11. EVALUATION OF QUANTITATIVE REAL TIME PCR FOR THE MEASUREMENT OF HELICOBATER PYLORI AT LOW CONCENTRATIONS IN DRINKING WATER

    EPA Science Inventory

    Aims: To determine the performance of a rapid, real time polymerase chain reaction (PCR) method for the detection and quantitative analysis Helicobacter pylori at low concentrations in drinking water.

    Methods and Results: A rapid DNA extraction and quantitative PCR (QPCR)...

  12. Measure it, See it, Manage it: Using Real Time Data to Benchmark,Optimize, and Sustain System Energy Efficiency

    SciTech Connect

    Taranto, Thomas; McKane, Aimee; Amon, Ricardo; Maulhardt, Michael

    2007-07-02

    Even after years of training and awareness building at thestate and national level, industrial cross-cutting systems (motor-driven,steam, process heating) continue to offer significant opportunities forenergy savings. The US Department of Energy estimates these remainingsavings at more than 7 percent of all industrial energy use. This paperpresents a different approach to promoting industrial system energyefficiency -- providing plant personnel with ready access to data uponwhich to base energy management decisions.In 2005, a Del Monte Foodsfruit processing plant in Modesto, California worked with LawrenceBerkeley National Laboratory (LBNL)to specify and purchase permanentinstrumentation for monitoring their compressed air system. This work,completed as part of a demonstration project under a State TechnologiesAdvancement Collaborative (STAC) grant, was designed to demonstrate theeffectiveness of enterprise energy management (EEM), which is predicatedon the assumption that the energy efficiency of existing, cross-cuttingindustrial systems (motor-driven, steam) can be improved by providingmanagement and operating personnel with real-time data on energy use. Theinitial STAC grant provided for the installation and some initialanalyses, but did not address the larger issue of integrating these newdata into an ongoing energy management program for the compressed airsystem.The California Energy Commission (CEC) decided to support furtheranalysis to identify potential for air system optimization. Through theCEC's Energy in Agriculture Program, a compressed air system audit wasperformed by Tom Taranto to: Measure and document the system's baselineand CASE Index of present operation; Establish methods to sustain anongoing CASE Index measure of performance; Use AIRMaster+ to analyzesupply side performance as compared to the CASE Index; Identify demandside opportunities for efficiency and performance improvement; Assesssupply / demand balance and energy reduction

  13. Learning to pronounce Vowel Sounds in a Foreign Language Using Acoustic Measurements of the Vocal Tract as Feedback in Real Time.

    ERIC Educational Resources Information Center

    Dowd, Annette; Smith, John; Wolfe, Joe

    1998-01-01

    Measured the first two vowel-tract resonances of a sample of native-French speakers for the non-nasalized vowels of that language. Values measured for native speakers for a particular vowel were used as target parameters for subjects who used a visual display of an impedance spectrum of their own vocal tracts as real time feedback to realize the…

  14. Real-time measurements of levoglucosan in fine aerosols (PM2.5) in the region of Paris (France)

    NASA Astrophysics Data System (ADS)

    Sciare, J.; Bonnaire, N.; Mocnik, G.; Bressi, M.; Petit, J.; Nicolas, J.; Sarda-Estève, R.

    2011-12-01

    Levoglucosan - one of the major saccharidic compounds produced by the combustion of cellulose and hemicellulose - is emitted in large amounts by wildfires or residential wood burning (during winter months). Over the past few years, this organic tracer has received more and more attention as it can be used in a quantitative way to derive atmospheric concentrations of biomass burning aerosols [Favez et al., 2010] which aerosol source has strong implications for climate and air quality studies. A new technique has been developed and is presented here to investigate real-time concentrations of levoglucosan in fine aerosols (PM2.5). This technique is based on a Particle-into-liquid-sampler (PILS, Brechtel Manufacturing inc., model 4002) used "on-line" and coupled with an electrospray ionisation - tandem mass spectrometry (ESI-MS/MS, Applied Biosystem model QTRAP 3200). Air was drawn in the PILS at 15LPM and removed from particles larger than 2.5μm aerodynamic diameter (AD) using a very sharp cyclone. Water-soluble aerosols were collected in the PILS and sent in the 10μL loop of the ESI-MS/MS at a flowrate of 50μL/min. Flow injection analysis (FIA) was then performed every 2.5min for the quantification of levoglucosan using ion source specific fragments (ions m/z 113). An internal levoglucosan standard was injected every 10 samples (i.e. every 25min) in order to check the stability of the mass spectrometry calibration. Field blanks were performed using a total filter upstream of the PILS instrument and did not show any detectable amount of levoglucosan. A limit of quantification (LOQ) better than 1 ng/m3 was calculated here for levoglucosan in FIA mode. Based on these settings, unattended measurements of levoglucosan by PILS-ESI-MS/MS have been performed every 2.5 min in the region of Paris for a couple of weeks during the winter 2011 showing concentrations ranging from below 1ng/m3 to more than 500ng/m3. These measurements were compared to measurements of Black

  15. Size-resolved, real-time measurement of water-insoluble aerosols in metropolitan Atlanta during the summer of 2004

    NASA Astrophysics Data System (ADS)

    Greenwald, Roby; Bergin, Michael H.; Weber, Rodney; Sullivan, Amy

    During the month of August 2004, the size-resolved number concentration of water-insoluble aerosols (WIA) from 0.25 to 2.0 μm was measured in real-time in the urban center of Atlanta, GA. Simultaneous measurements were performed for the total aerosol size distribution from 0.1 to 2.0 μm, the elemental and organic carbon mass concentration, the aerosol absorption coefficient, and the aerosol scattering coefficient at a dry (RH=30%) humidity. The mean aerosol number concentration in the size range 0.1-2.0 μm was found to be 360±175 cm -3, but this quantity fluctuated significantly on time scales of less than one hour and ranged from 25 to 1400 cm -3 during the sample period. The mean WIA concentration (0.25-2.0 μm) was 13±7 cm -3 and ranged from 1 to 60 cm -3. The average insoluble fraction in the size range 0.25-2.0 μm was found to be 4±2.5% with a range of 0.3-38%. The WIA population was found to follow a consistent diurnal pattern throughout the month with concentration maxima concurring with peaks in vehicular traffic flow. WIA concentration also responded to changes in meteorological conditions such as boundary layer depth and precipitation events. The temporal variability of the absorption coefficient followed an identical pattern to that of WIA and ranged from below the detection limit to 55 Mm -1 with a mean of 8±6 Mm -1. The WIA concentration was highly correlated with both the absorption coefficient and the elemental carbon mass concentration, suggesting that WIA measurements are dominated by fresh emissions of elemental carbon. For both the total aerosol and the WIA size distributions, the maximum number concentration was observed at the smallest sizes; however the WIA size distribution also exhibited a peak at 0.45 μm which was not observed in the total population. Over 60% of the particles greater than 1.0 μm were observed to be insoluble in the water sampling stream used by this instrumentation. Due to the refractive properties of black

  16. Feasibility of interactive text message response (ITR) as a novel, real-time measure of adherence to antiretroviral therapy for HIV+ youth.

    PubMed

    Dowshen, Nadia; Kuhns, Lisa M; Gray, Camdin; Lee, Susan; Garofalo, Robert

    2013-07-01

    Youth living with HIV/AIDS (YLH) face unique challenges to optimal adherence to antiretroviral therapy (ART). Accurate, real-time methods to assess adherence are needed to facilitate early intervention and promote viral suppression. The purpose of this study was to assess the feasibility and validity of interactive text message response (ITR) as a measure of adherence to ART among YLH. This study was part of a larger pilot text message reminder intervention conducted at a US community-based, LGBT-focused health center providing clinical services to YLH. Eligibility criteria for this pilot study included HIV-positive serostatus, aged 14-29, use of personal cell phone, English-speaking, and on ART with demonstrated adherence difficulties. During the 24-week study period, participants received personalized daily short message system reminders with a follow-up message 1 hour later asking whether they took medication and directing a response via return text message. To determine whether or not ITR would be a feasible, valid measure of adherence, we calculated the proportion of positive responses indicating medication had been taken divided by the total number of messages requesting a response and compared this response rate to a self-reported adherence measure, the visual analogue scale (VAS). Participants (n = 25) were on average 23 years old, largely male (92%), Black (60%) and behaviorally infected (84%). Over the course of the intervention, study participants responded to prompts via text to indicate whether or not they had taken their medication approximately 61% of the time. The overall mean ITR adherence rate (i.e., positive responses) was 57.4% (SD = 28.5%). ITR and VAS measures were moderately, positively correlated (r = 0.52, p < 0.05) during the first 6 weeks of the study period. ITR adherence rates were significantly higher on weekdays versus weekends (p < 0.05). This pilot study showed both moderate responsiveness of individuals to daily ITR and a moderate

  17. Real-time detection of airborne chemicals

    NASA Astrophysics Data System (ADS)

    Hartenstein, Steven D.; Tremblay, Paul L. A.; Fryer, Michael O.; Kaser, Timothy

    1999-02-01

    Accurate, real time air quality measurements are difficult to make, because real time sensors for some gas species are not specific to a single gas. For example, some carbon dioxide sensors react to hydrogen sulfide. By combining the response of several types of real time gas sensors the Real-time Air Quality Monitoring System (RAQMS) accurately measures many different gases. The sensor suite for the INEEL's Real-time Air Quality Monitoring System (RAQMS) incudes seven, inexpensive, commercially-available chemical sensors for gases associated with air quality. These chemical sensors are marketed as devices to measure carbon dioxide, hydrogen sulfide, carbon monoxide, sulfur dioxide, nitrogen dioxide, water vapor and volatile organic compounds (VOC's). However, these chemical sensors respond to more than a single compound, e.g. both the VOC and the carbon dioxide sensors respond strongly to methane. This multiple sensor response to a given chemical is used to advantage in the RAQMS system, as patterns of responses by the sensors were found to be unique and distinguishable for several chemicals. Therefore, there is the potential that the seven sensors combined output can: (1) provide more accurate measurements of the advertized gases and (2) estimate the presence and quantity of additional gases. The patterns of sensor response can be thought of as clusters of data points in a seven dimensional space. One dimension for each sensor's output. For all of the gases tested, these clusters were separated enough that good quantitative results were obtained. As an example, the prototype RAQMS is able to distinguish methane from butane and predict accurate concentrations of both gases. A mathematical technique for estimating probability density functions from random samples is used to distinguish the data clusters from each other and to make gas concentration estimates. Bayes optimal estimates of gas concentration are calculated using the probability density function. The

  18. Correlation between bioaerosol microbial community characteristics and real-time measurable environmental items: A case study from KORUS-AQ pre-campaign in Seoul, Korea

    NASA Astrophysics Data System (ADS)

    Yoo, H.

    2015-12-01

    Due to global climate change, bioaerosols are more globally mixed with a more random manner. During a long-distance traveling dust event, the number of microbes significantly increases in bioaerosol, and the chance for bioaerosol to contain human pathogenic microorganisms may also increase. Recently, we have found that bioaerosol microbial community characteristics (copy number of total bacterial 16S rRNA genes, and population diversity and composition) are correlated with the quantitative detection of potential human pathogens. However, bioaerosol microbial community characteristics cannot be directly used in real-time monitoring because the DNA-based detection method requires at least couple days or a week to get reliable data. To circumvent this problem, a correlation of microbial community characteristics with real-time measurable environmental items (PM10, PM2.5, temperature, humidity, NOx, O3 etc.), if any, will be useful in frequent assessment of microbial risk from available real-time measured environmental data. In this work, we monitored bioaerosol microbial communities using a high-throughput DNA sequencing method (Mi-seq) during the KORUS-AQ (KoreaUS-Air Quality) pre-campaign (May to June, 2015) in Seoul, and investigated whether any correlation exists between the bioaerosol microbial community characteristics and the real-time measureable environmental items simultaneously attained during the pre-campaign period. At the pre-campaign site (Korea Institute of Science and Technology, Seoul), bioaerosol samples were collected using high volume air sampler, and their 16S rRNA gene based bacterial communities were analyzed by Miseq sequencing and bioinformatics. Simultaneously, atmosphere environmental items were monitored at the same site. Using Decision Tree, a non-linear multi-variant correlation was observed between the bioaerosol microbial community characteristics and the real-time measured atmosphere chemistry data, and a rule induction was developed

  19. Near-real-time trace element measurements in a rural, traffic-influenced environment with some fireworks

    NASA Astrophysics Data System (ADS)

    Furger, Markus; Slowik, Jay G.; Cruz Minguillón, María; Hueglin, Christoph; Koch, Chris; Prévôt, André S. H.; Baltensperger, Urs

    2016-04-01

    Aerosol-bound trace elements can affect the environment in significant ways especially when they are toxic. Characterizing the trace element spatial and temporal variability is a prerequisite for human exposure studies. The requirement for high time resolution and consequently the low sample masses asked for analysis methods not easily accessible, such as synchrotron radiation-induced X-ray fluorescence spectrometry (SR-XRF). In recent years, instrumentation that samples and analyzes airborne particulate matter with time resolutions of less than an hour in near real time has entered the market. We present the results of a three-week campaign in a rural environment close to a freeway. The measurement period included the fireworks of the Swiss National Day. The XRF instrument was set up at the monitoring station Härkingen of the Swiss Monitoring Network for Air Pollution (NABEL). It was configured to sample and analyze ambient PM10 aerosols in 1-hour intervals. Sample analysis with XRF was performed by the instrument immediately after collection, i.e. during the next sampling interval. 24 elements were analyzed and quantified (Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Sn, Sb, Ba, Pt, Hg, Pb, Bi). The element concentrations obtained by the XRF instrument were compared to those determined by ICP-AES and ICP-MS in PM10 samples collected by NABEL high volume samplers. The results demonstrate the capability of the instrument to measure over a wide range of concentrations, from a few ng m‑3 to μg m‑3, under ambient conditions. The time resolution allows for the characterization of diurnal variations of element concentrations, which provides information on the contribution of emission sources, such as road traffic, soil, or fireworks. Some elements (V, Co, As, Pt) were below their detection limit during most of the time, but As could be quantified during the fireworks. Transition metals Cr, Mn, Fe, Cu, Zn could be attributed to freeway traffic

  20. Real-Time Secondary Aerosol Formation Measurements using a Photooxidation Reactor (PAM) and AMS in Urban Air and Biomass Smoke

    NASA Astrophysics Data System (ADS)

    Ortega, A. M.; Cubison, M.; Hayes, P. L.; Brune, W. H.; Hu, W.; Flynn, J. H.; Grossberg, N.; Lefer, B. L.; Alvarez, S. L.; Rappenglueck, B.; Bon, D.; Graus, M.; Warneke, C.; Gilman, J. B.; Kuster, W. C.; De Gouw, J. A.; Sullivan, A. P.; Jimenez, J. L.

    2011-12-01

    Recent field studies reveal large formation of secondary organic aerosol (SOA) under urban polluted ambient conditions, while SOA formation in biomass burning smoke appears to be variable but sometimes substantial. To study this formation in real-time, a Potential Aerosol Mass (PAM) photooxidation reactor was deployed with submicron aerosol size and chemical composition measurements during two studies: FLAME-3, a biomass-burning study at USDA Fire Sciences Laboratory in Missoula in 2009, MT and CalNex-LA in Pasadena, CA in 2010. A high-resolution aerosol mass spectrometer (HR-AMS) and a scanning mobility particle sizer (SMPS) alternated sampling unprocessed and PAM-processed aerosol. The PAM reactor produces OH concentrations up to 4 orders of magnitude higher than in ambient air, achieving equivalent aging of ~2 weeks in 5 minutes of processing. The OH intensity was also scanned every 20 min. in both field studies. Results show the value of PAM-AMS as a tool for in-situ evaluation of changes in OA concentration and composition due to SOA formation and POA oxidation. In FLAME-3, net SOA formation was variable among smokes from different biomasses; however, OA oxidation was always observed. The average SOA enhancement factor was 1.7 +/- 0.5 of the initial POA. Reactive VOCs such as toluene, monoterpenes, and acetaldehyde, as measured from a PIT-MS, decreased with increased PAM processing; however, formic acid, acetone, and some unidentified OVOCs increased after significant exposure to high oxidant levels suggesting multigenerational chemistry. Results from CalNex-LA show enhancement of SOA and inorganic aerosol from gas-phase precursors. This enhanced OA mass increase from PAM processing is maximum at night and correlates with trimethylbenzene concentrations, which indicates the dominance of short-lived SOA precursors in the LA Basin. A traditional SOA model with mostly aromatic precursors underpredicts the amount of SOA formed by about an order-of-magnitude, which

  1. Interaction of on-site and near real time measured turbidity and enzyme activity in stream water.

    NASA Astrophysics Data System (ADS)

    Stadler, Philipp; Farnleitner, Andreas H.; Zessner, Matthias

    2013-04-01

    On-site and on-line systems that provide an integrated surveillance of physicochemical and microbiological parameters gain significance in water quality monitoring. Particular relating to diffuse pollution from agricultural areas and use-orientated protection of waters the detection of faecal pollution is a fundamental part. For the near real time and on-site detection of microbiological faecal pollution of water, the beta-D- Glucuronidase (GLUC) enzymatic activity has been suggested as a surrogate parameter. Due to possible short measure intervals of three hours, this method has high potential as a water quality monitoring tool. While cultivation based standard determination takes more than one working day (Cabral 2010) the potential advantage of detecting the GLUC activity is the high temporal measuring resolution. Yet, there is still a big gap of knowledge on the sensitivity and specificity concerning the faecal indication capacity of GLUC in relation to standard assays (Cabral 2010). Interference effects of physicochemical parameters on the enzymatic activity respectively fluorescence have been discussed (Molina-Munoz et al. 2007; Tryland and Fiksdal 1998, Biswal et al. 2003). Results from a monitoring of a rivulet in an agricultural catchment in Lower Austria (HOAL - Hydrological Open Air Laboratory) are presented here. The HOAL offers technical resources that allow measurements at high temporal and spatial resolution and to apply various hydrological methods in one catchment. Two automated enzymatic measuring devices (Coliguard, mbOnline, Austria) and physicochemical in-stream measurements are used, as well as in-stream spectroscopy (spectrolyser, s::can, Austria). Accuracy of both enzymatic measuring devices is compared through diverse hydrological and seasonal conditions. Reference analyses by cultivation based determination were performed. Data from Coliguard devices is combined with physicochemical and spectroscopy data to gain information about the

  2. Real Time Radiation Exposure And Health Risks

    NASA Technical Reports Server (NTRS)

    Hu, Shaowen; Barzilla, Janet E.; Semones, Edward J.

    2015-01-01

    Radiation from solar particle events (SPEs) poses a serious threat to future manned missions outside of low Earth orbit (LEO). Accurate characterization of the radiation environment in the inner heliosphere and timely monitoring the health risks to crew are essential steps to ensure the safety of future Mars missions. In this project we plan to develop an approach that can use the particle data from multiple satellites and perform near real-time simulations of radiation exposure and health risks for various exposure scenarios. Time-course profiles of dose rates will be calculated with HZETRN and PDOSE from the energy spectrum and compositions of the particles archived from satellites, and will be validated from recent radiation exposure measurements in space. Real-time estimation of radiation risks will be investigated using ARRBOD. This cross discipline integrated approach can improve risk mitigation by providing critical information for risk assessment and medical guidance to crew during SPEs.

  3. Steering a mobile robot in real time

    NASA Astrophysics Data System (ADS)

    Chuah, Mei C.; Fennema, Claude L., Jr.

    1994-10-01

    Using computer vision for mobile robot navigation has been of interest since the 1960s. This interest is evident in even the earliest robot projects: at SRI International (`Shakey') and at the Stanford University (`Stanford Cart'). These pioneering projects provided a foundation for late work but fell far short of providing real time solutions. Since the mid 1980s, the ARPA sponsored ALV and UGV projects have established a need for real time navigation. To achieve the necessary speed, some researchers have focused on building faster hardware; others have turned to the use of new computational architectures, such as neural nets. The work described in this paper uses another approach that has become known as `perceptual servoing.' Previously reported results show that perceptual servoing is both fast and accurate when used to steer vehicles equipped with precise odometers. When the instrumentation on the vehicle does not give precise measurements of distance traveled, as could be the case for a vehicle traveling on ice or mud, new techniques are required to accommodate the reduced ability to make accurate predictions about motion and control. This paper presents a method that computes estimates of distance traveled using landmarks and path information. The new method continues to perform in real time using modest computational facilities, and results demonstrate the effects of the new implementation on steering accuracy.

  4. Accurate Mass Measurements in Proteomics

    SciTech Connect

    Liu, Tao; Belov, Mikhail E.; Jaitly, Navdeep; Qian, Weijun; Smith, Richard D.

    2007-08-01

    To understand different aspects of life at the molecular level, one would think that ideally all components of specific processes should be individually isolated and studied in details. Reductionist approaches, i.e., studying one biological event at a one-gene or one-protein-at-a-time basis, indeed have made significant contributions to our understanding of many basic facts of biology. However, these individual “building blocks” can not be visualized as a comprehensive “model” of the life of cells, tissues, and organisms, without using more integrative approaches.1,2 For example, the emerging field of “systems biology” aims to quantify all of the components of a biological system to assess their interactions and to integrate diverse types of information obtainable from this system into models that could explain and predict behaviors.3-6 Recent breakthroughs in genomics, proteomics, and bioinformatics are making this daunting task a reality.7-14 Proteomics, the systematic study of the entire complement of proteins expressed by an organism, tissue, or cell under a specific set of conditions at a specific time (i.e., the proteome), has become an essential enabling component of systems biology. While the genome of an organism may be considered static over short timescales, the expression of that genome as the actual gene products (i.e., mRNAs and proteins) is a dynamic event that is constantly changing due to the influence of environmental and physiological conditions. Exclusive monitoring of the transcriptomes can be carried out using high-throughput cDNA microarray analysis,15-17 however the measured mRNA levels do not necessarily correlate strongly with the corresponding abundances of proteins,18-20 The actual amount of functional proteins can be altered significantly and become independent of mRNA levels as a result of post-translational modifications (PTMs),21 alternative splicing,22,23 and protein turnover.24,25 Moreover, the functions of expressed

  5. Real-Time Parameter Estimation in the Frequency Domain

    NASA Technical Reports Server (NTRS)

    Morelli, Eugene A.

    1999-01-01

    A method for real-time estimation of parameters in a linear dynamic state space model was developed and studied. The application is aircraft dynamic model parameter estimation from measured data in flight for indirect adaptive or reconfigurable control. Equation error in the frequency domain was used with a recursive Fourier transform for the real-time data analysis. Linear and nonlinear simulation examples and flight test data from the F-18 High Alpha Research Vehicle HARV) were used to demonstrate that the technique produces accurate model parameter estimates with appropriate error bounds. Parameter estimates converged in less than 1 cycle of the dominant dynamic mode natural frequencies, using control surface inputs measured in flight during ordinary piloted maneuvers. The real-time parameter estimation method has low computational requirements, and could be implemented aboard an aircraft in real time.

  6. Flux Chamber Measurements of Methane Emissions and Stable Isotope Composition from an Arctic Wetland Using Field-Deployed Real-Time CRDS Vs Lab Measurements

    NASA Astrophysics Data System (ADS)

    Thompson, H. A.; Stern, J. C.; Graham, H. V.; Pratt, L. M.; White, J. R.

    2014-12-01

    The emission of CH4 from Arctic landscapes under warming climate is an important feedback in Earth's climate system. Studies of CH4 flux from Arctic wetlands have been growing in recent years, but few provide details on biogeochemical controls. Stable isotopic measurements help elucidate methane production and consumption pathways and offer important understanding about dynamics of CH4 cycling in Arctic systems. In order to demonstrate the possible instrumental approaches to measuring methane dynamics of wetlands in the Arctic, a fringing wetland of a small lake near the Russell Glacier in Southwestern Greenland was outfitted with static flux chambers and instrumented with a field-deployable Cavity Ring Down Spectrometer (CRDS) to measure real-time concentrations of CH4 and CO2 and their stable carbon isotopes. Several different wetland plant communities were included in the flux chamber experiments and field tests were conducted during several weeks in July 2014. Analytical measurements by CRDS were compared to batch samples analyzed in the laboratory using both Off-Axis Integrated Cavity Output Spectroscopy (ICOS) and Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry (GC-C-IRMS) with cryogenic pre-concentration. Results from flux chamber deployments will be presented and comparisons between the real-time field measurements and laboratory instrumental techniques will be evaluated.

  7. Real-Time Geospatial Data Viewer (RETIGO): Web-Based Tool for Researchers and Citizen Scientists to Explore their Air Measurements

    EPA Science Inventory

    The collection of air measurements in real-time on moving platforms, such as wearable, bicycle-mounted, or vehicle-mounted air sensors, is becoming an increasingly common method to investigate local air quality. However, visualizing and analyzing geospatial air monitoring data re...

  8. FIELD EVALUATION OF A MODIFIED DATARAM MIE SCATTERING MONITOR FOR REAL-TIME PM2.5 MASS CONCENTRATION MEASUREMENTS. (R827352C005)

    EPA Science Inventory

    In this paper, we investigated the feasibility of using a modified DataRAM nephelometer (RAM-1, MIE Inc., Billerica, MA) as a continuous PM2.5 monitor to measure concentrations of ambient and concentrated aerosols in real time. The DataRAM operated with a diffusion ...

  9. REAL-TIME AND INTEGRATED MEASUREMENT OF POTENTIAL HUMAN EXPOSURE TO PARTICLE-BOUND POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) FROM AIRCRAFT EXHAUST

    EPA Science Inventory

    Real-time monitors and low-volume air samplers were used to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. Three...

  10. New digital measurement methods for left ventricular volume using real-time three-dimensional echocardiography: comparison with electromagnetic flow method and magnetic resonance imaging

    NASA Technical Reports Server (NTRS)

    Qin, J. J.; Jones, M.; Shiota, T.; Greenberg, N. L.; Firstenberg, M. S.; Tsujino, H.; Zetts, A. D.; Sun, J. P.; Cardon, L. A.; Odabashian, J. A.; Flamm, S. D.; White, R. D.; Panza, J. A.; Thomas, J. D.

    2000-01-01

    AIM: The aim of this study was to investigate the feasibility and accuracy of using symmetrically rotated apical long axis planes for the determination of left ventricular (LV) volumes with real-time three-dimensional echocardiography (3DE). METHODS AND RESULTS: Real-time 3DE was performed in six sheep during 24 haemodynamic conditions with electromagnetic flow measurements (EM), and in 29 patients with magnetic resonance imaging measurements (MRI). LV volumes were calculated by Simpson's rule with five 3DE methods (i.e. apical biplane, four-plane, six-plane, nine-plane (in which the angle between each long axis plane was 90 degrees, 45 degrees, 30 degrees or 20 degrees, respectively) and standard short axis views (SAX)). Real-time 3DE correlated well with EM for LV stroke volumes in animals (r=0.68-0.95) and with MRI for absolute volumes in patients (r-values=0.93-0.98). However, agreement between MRI and apical nine-plane, six-plane, and SAX methods in patients was better than those with apical four-plane and bi-plane methods (mean difference = -15, -18, -13, vs. -31 and -48 ml for end-diastolic volume, respectively, P<0.05). CONCLUSION: Apically rotated measurement methods of real-time 3DE correlated well with reference standards for calculating LV volumes. Balancing accuracy and required time for these LV volume measurements, the apical six-plane method is recommended for clinical use.

  11. Independent Analysis of Real-Time, Measured Performance Data From Microcogenerative Fuel Cell Systems Installed in Buildings

    SciTech Connect

    Dillon, Heather E.; Colella, Whitney G.

    2015-06-01

    Pacific Northwest National Laboratory (PNNL) is working with industry to independently monitor up to 15 distinct 5 kW-electric (kWe) combined heat and power (CHP) high temperature (HT) proton exchange membrane (PEM) fuel cell systems (FCSs) installed in light commercial buildings. This research paper discusses an evaluation of the first six months of measured performance data acquired at a 1 s sampling rate from real-time monitoring equipment attached to the FCSs at building sites. Engineering performance parameters are independently evaluated. Based on an analysis of the first few months of measured operating data, FCS performance is consistent with manufacturer-stated performance. Initial data indicate that the FCSs have relatively stable performance and a long-term average production of about 4.57 kWe of power. This value is consistent with, but slightly below, the manufacturer's stated rated electric power output of 5 kWe. The measured system net electric efficiency has averaged 33.7%, based on the higher heating value (HHV) of natural gas fuel. This value, also, is consistent with, but slightly below, the manufacturer's stated rated electric efficiency of 36%. The FCSs provide low-grade hot water to the building at a measured average temperature of about 48.4 degrees C, lower than the manufacturer's stated maximum hot water delivery temperature of 65 degrees C. The uptime of the systems is also evaluated. System availability can be defined as the quotient of total operating time compared to time since commissioning. The average values for system availability vary between 96.1 and 97.3%, depending on the FCS evaluated in the field. Performance at rated value for electrical efficiency (PRVeff) can be defined as the quotient of the system time operating at or above the rated electric efficiency and the time since commissioning. The PRVeff varies between 5.6% and 31.6%, depending on the FCS field unit evaluated. Performance at rated value for electrical power

  12. Validation of reference genes for accurate normalization of gene expression for real time-quantitative PCR in strawberry fruits using different cultivars and osmotic stresses.

    PubMed

    Galli, Vanessa; Borowski, Joyce Moura; Perin, Ellen Cristina; Messias, Rafael da Silva; Labonde, Julia; Pereira, Ivan dos Santos; Silva, Sérgio Delmar Dos Anjos; Rombaldi, Cesar Valmor

    2015-01-10

    The increasing demand of strawberry (Fragaria×ananassa Duch) fruits is associated mainly with their sensorial characteristics and the content of antioxidant compounds. Nevertheless, the strawberry production has been hampered due to its sensitivity to abiotic stresses. Therefore, to understand the molecular mechanisms highlighting stress response is of great importance to enable genetic engineering approaches aiming to improve strawberry tolerance. However, the study of expression of genes in strawberry requires the use of suitable reference genes. In the present study, seven traditional and novel candidate reference genes were evaluated for transcript normalization in fruits of ten strawberry cultivars and two abiotic stresses, using RefFinder, which integrates the four major currently available software programs: geNorm, NormFinder, BestKeeper and the comparative delta-Ct method. The results indicate that the expression stability is dependent on the experimental conditions. The candidate reference gene DBP (DNA binding protein) was considered the most suitable to normalize expression data in samples of strawberry cultivars and under drought stress condition, and the candidate reference gene HISTH4 (histone H4) was the most stable under osmotic stresses and salt stress. The traditional genes GAPDH (glyceraldehyde-3-phosphate dehydrogenase) and 18S (18S ribosomal RNA) were considered the most unstable genes in all conditions. The expression of phenylalanine ammonia lyase (PAL) and 9-cis epoxycarotenoid dioxygenase (NCED1) genes were used to further confirm the validated candidate reference genes, showing that the use of an inappropriate reference gene may induce erroneous results. This study is the first survey on the stability of reference genes in strawberry cultivars and osmotic stresses and provides guidelines to obtain more accurate RT-qPCR results for future breeding efforts. PMID:25445290

  13. Real-time radiography

    SciTech Connect

    Bossi, R.H.; Oien, C.T.

    1981-02-26

    Real-time radiography is used for imaging both dynamic events and static objects. Fluorescent screens play an important role in converting radiation to light, which is then observed directly or intensified and detected. The radiographic parameters for real-time radiography are similar to conventional film radiography with special emphasis on statistics and magnification. Direct-viewing fluoroscopy uses the human eye as a detector of fluorescent screen light or the light from an intensifier. Remote-viewing systems replace the human observer with a television camera. The remote-viewing systems have many advantages over the direct-viewing conditions such as safety, image enhancement, and the capability to produce permanent records. This report reviews real-time imaging system parameters and components.

  14. Closed-loop 15N measurement of N2O and its isotopomers for real-time greenhouse gas tracing

    NASA Astrophysics Data System (ADS)

    Slaets, Johanna; Mayr, Leopold; Heiling, Maria; Zaman, Mohammad; Resch, Christian; Weltin, Georg; Gruber, Roman; Dercon, Gerd

    2016-04-01

    Quantifying sources of nitrous oxide is essential to improve understanding of the global N cycle and to develop climate-smart agriculture, as N2O has a global warming potential 300 times higher than CO2. The isotopic signature and the intramolecular distribution (site preference) of 15N are powerful tools to trace N2O, but the application of these methods is limited as conventional methods cannot provide continuous and in situ data. Here we present a method for closed-loop, real time monitoring of the N2O flux, the isotopic signature and the intramolecular distribution of 15N by using off-axis integrated cavity output spectroscopy (ICOS, Los Gatos Research). The developed method was applied to a fertilizer inhibitor experiment, in which N2O emissions were measured on undisturbed soil cores for three weeks. The treatments consisted of enriched urea-N (100 kg urea-N/ha), the same fertilizer combined with the nitrification inhibitor nitrapyrin (375 g/100 kg urea), and control cores. Monitoring the isotopic signature makes it possible to distinguish emissions from soil and fertilizer. Characterization of site preference could additionally provide a tool to identify different microbial processes leading to N2O emissions. Furthermore, the closed-loop approach enables direct measurement on site and does not require removal of CO2 and H2O. Results showed that 75% of total N2O emissions (total=11 346 μg N2O-N/m2) in the fertilized cores originated from fertilizer, while only 55% of total emissions (total=2 450 μg N2ON/m2) stemmed from fertilizer for the cores treated with nitrapyrin. In the controls, N2O derived from soil was only 40% of the size of the corresponding pool from the fertilized cores, pointing towards a priming effect on the microbial community from the fertilizer and demonstrating the bias that could be introduced by relying on non-treated cores to estimate soil emission rates, rather than using the isotopic signature. The site preference increased linearly

  15. Two-dimensional tissue tracking: a novel echocardiographic technique to measure left atrial volume: comparison with biplane area length method and real time three-dimensional echocardiography.

    PubMed

    Li, Shi-Yan; Zhang, Li; Zhao, Bo-Wen; Yu, Chan; Xu, Li-Long; Li, Peng; Xu, Ke; Pan, Mei; Wang, Bei

    2014-07-01

    Enlargement of the left atrium is an independent predictor of adverse cardiovascular outcomes, and an accurate, convenient imaging modality is necessary for clinical practice. The objectives of this study were to evaluate the feasibility of a novel imaging technique, two-dimensional tissue tracking (2DTT), for assessment of left atrial (LA) volume and function and to compare its correlation and agreement with biplane area length (AL) method and real time three-dimensional echocardiography (RT3DE). A total of 105 patients prospectively underwent 2DTT, AL and RT3DE. The LA volume index (LAVI) and emptying fraction were measured. In addition, intra- and inter-observer agreement were calculated by using the intraclass correlation coefficient. There were no significant differences in LAVI and emptying fraction measured by 2DTT in comparison with those made by AL or RT3DE, furthermore Bland-Altman analysis showed that 2DTT had significantly better agreement for LAVI and emptying fraction with AL and RT3DE. 2DTT also exhibited smaller intra- and inter-observer variability as compared with AL or RT3DE. Furthermore, the time to measure LA volume and acquire time-volume curve was significantly less by 2DTT than that by RT3DE (U = 49.00, P < 0.001). These observations suggest that the 2DTT could provide valuable information which is consistent with the standard AL and RT3DE measurements for LAVI and function with potentially lower intra- and inter-observer variability. PMID:24460543

  16. Acoustic Emission and Velocity Measurements using a Modular Borehole Prototype Tool to Provide Real Time Rock Mass Characterization.

    NASA Astrophysics Data System (ADS)

    Collins, D. S.; Pettitt, W. S.; Young, R. P.

    2003-04-01

    Permanent changes to rock mass properties can occur due to the application of excavation or thermal induced stresses. This project involves the design of hardware and software for the long term monitoring of a rock volume, and the real time analysis and interpretation of induced microcracks and their properties. A set of borehole sondes have been designed with each sonde containing up to 6 sensor modules. Each piezoelectric sensor is dual mode allowing it to either transmit an ultrasonic pulse through a rock mass, or receive ultrasonic waveform data. Good coupling of the sensors with the borehole wall is achieved through a motorized clamping mechanism. The borehole sondes are connected to a surface interface box and digital acquisition system and controlled by a laptop computer. The system allows acoustic emission (AE) data to be recorded at all times using programmable trigger logic. The AE data is processed in real time for 3D source location and magnitude, with further analysis such as mechanism type available offline. Additionally the system allows velocity surveys to be automatically performed at pre-defined times. A modelling component of the project, using a 3D dynamic finite difference code, is investigating the effect that different microcrack distributions have on velocity waveform data in terms of time and frequency amplitude. The modelling codes will be validated using data recorded from laboratory tests on rocks with known crack fabrics, and then used in insitu experimental tests. This modelling information will be used to help interpret, in real time, microcrack characteristics such as crack density, size, and fluid content. The technology has applications in a number of branches of geotechnical and civil engineering including radioactive waste storage, mining, dams, bridges, and oil reservoir monitoring.

  17. Optimizing the real-time ground level enhancement alert system based on neutron monitor measurements: Introducing GLE Alert Plus

    NASA Astrophysics Data System (ADS)

    Souvatzoglou, G.; Papaioannou, A.; Mavromichalaki, H.; Dimitroulakos, J.; Sarlanis, C.

    2014-11-01

    Whenever a significant intensity increase is being recorded by at least three neutron monitor stations in real-time mode, a ground level enhancement (GLE) event is marked and an automated alert is issued. Although, the physical concept of the algorithm is solid and has efficiently worked in a number of cases, the availability of real-time data is still an open issue and makes timely GLE alerts quite challenging. In this work we present the optimization of the GLE alert that has been set into operation since 2006 at the Athens Neutron Monitor Station. This upgrade has led to GLE Alert Plus, which is currently based upon the Neutron Monitor Database (NMDB). We have determined the critical values per station allowing us to issue reliable GLE alerts close to the initiation of the event while at the same time we keep the false alert rate at low levels. Furthermore, we have managed to treat the problem of data availability, introducing the Go-Back-N algorithm. A total of 13 GLE events have been marked from January 2000 to December 2012. GLE Alert Plus issued an alert for 12 events. These alert times are compared to the alert times of GOES Space Weather Prediction Center and Solar Energetic Particle forecaster of the University of Málaga (UMASEP). In all cases GLE Alert Plus precedes the GOES alert by ≈8-52 min. The comparison with UMASEP demonstrated a remarkably good agreement. Real-time GLE alerts by GLE Alert Plus may be retrieved by http://cosray.phys.uoa.gr/gle_alert_plus.html, http://www.nmdb.eu, and http://swe.ssa.esa.int/web/guest/space-radiation. An automated GLE alert email notification system is also available to interested users.

  18. The JPL near-real-time VLBI system and its application to clock synchronization and earth orientation measurements

    NASA Technical Reports Server (NTRS)

    Callahan, P. S.; Eubanks, T. M.; Roth, M. G.; Steppe, J. A.; Esposito, P. B.

    1983-01-01

    The JPL near-real-time VLBI system called Block I is discussed. The hardware and software of the system are described, and the Time and Earth Motion Precision Observations (TEMPO) which utilize Block I are discussed. These observations are designed to provide interstation clock synchronization to 10 nsec and to determine earth orientation (UT1 and polar motion - UTPM) to 30 cm or better in each component. TEMPO results for clock synchronization and UTPM are presented with data from the July 1980-August 1981 analyzed using the most recent JPL solution software and source catalog. Future plans for TEMPO and Block I are discussed.

  19. Are emissions of black carbon from gasoline vehicles overestimated? Real-time, in situ measurement of black carbon emission factors.

    PubMed

    Wang, Yang; Xing, Zhenyu; Zhao, Shuhui; Zheng, Mei; Mu, Chao; Du, Ke

    2016-03-15

    Accurately quantifying black carbon (BC) emission factors (EFs) is a prerequisite for estimation of BC emission inventory. BC EFs determined by measuring BC at the roadside or chasing a vehicle on-road may introduce large uncertainty for low emission vehicles. In this study, BC concentrations were measured inside the tailpipe of gasoline vehicles with different engine sizes under different driving modes to determine the respective EFs. BC EFs ranged from 0.005-7.14 mg/kg-fuel under the speeds of 20-70 km/h, 0.05-28.95 mg/kg-fuel under the accelerations of 0.5-1.5m/s(2). Although the water vapor in the sampling stream could result in an average of 12% negative bias, the BC EFs are significantly lower than the published results obtained with roadside or chasing vehicle measurement. It is suggested to conduct measurement at the tailpipe of gasoline vehicles instead of in the atmosphere behind the vehicles to reduce the uncertainty from fluctuation in ambient BC concentration. PMID:26799329

  20. Quantification of Low-Level Drug Effects Using Real-Time, in vitro Measurement of Oxygen Consumption Rate.

    PubMed

    Neal, Adam; Rountree, Austin M; Philips, Craig W; Kavanagh, Terrance J; Williams, Dominic P; Newham, Peter; Khalil, Gamal; Cook, Daniel L; Sweet, Ian R

    2015-12-01

    There is a general need to detect toxic effects of drugs during preclinical screening. We propose that increased sensitivity of xenobiotics toxicity combined with improved in vitro physiological recapitulation will more accurately assess potentially toxic perturbations of cellular biochemistry that are near in vivo pharmacological exposure levels. Importantly, measurement of such cytopathologies avoids activating mechanisms mediating toxicity at suprapharmacologic levels not relevant to in vivo effects. We present a sensitive method to measure changes in oxygen consumption rate (OCR), a well-established parameter reflecting a potential hazard, in response to exposure to pharmacologic levels of drugs using a flow culture system and state of the art oxygen sensing system. We tested metformin and acetaminophen on rat liver slices to illustrate the method. The features of the method include continuous and very stable measurement of OCR over the course of 48 h in liver slices in a continuous flow chamber with the ability to resolve changes as small as 0.3%/h. Kinetic modeling of metformin inhibition of OCR over a wide range of concentrations revealed both a slow and fast mechanism, where the fast mechanism activated only at concentrations above 0.6 mM. For both drugs, small amounts of inhibition were reversible, but higher decrements were irreversible. Overall the study highlights the advantages of measuring low-level toxicity so as to avoid the common extrapolations made about drug toxicity based on effects of drugs tested at suprapharmacologic levels. PMID:26396153

  1. Electric cell-substrate impedance sensing (ECIS) based real-time measurement of titer dependent cytotoxicity induced by adenoviral vectors in an IPI-2I cell culture model.

    PubMed

    Müller, Jakob; Thirion, Christian; Pfaffl, Michael W

    2011-01-15

    Recombinant viral vectors are widespread tools for transfer of genetic material in various modern biotechnological applications like for example RNA interference (RNAi). However, an accurate and reproducible titer assignment represents the basic step for most downstream applications regarding a precise multiplicity of infection (MOI) adjustment. As necessary scaffold for the studies described in this work we introduce a quantitative real-time PCR (qPCR) based approach for viral particle measurement. Still an implicated problem concerning physiological effects is that the appliance of viral vectors is often attended by toxic effects on the individual target. To determine the critical viral dose leading to cell death we developed an electric cell-substrate impedance sensing (ECIS) based assay. With ECIS technology the impedance change of a current flow through the cell culture medium in an array plate is measured in a non-invasive manner, visualizing effects like cell attachment, cell-cell contacts or proliferation. Here we describe the potential of this online measurement technique in an in vitro model using the porcine ileal epithelial cell line IPI-2I in combination with an adenoviral transfection vector (Ad5-derivate). This approach shows a clear dose-depending toxic effect, as the amount of applied virus highly correlates (p<0.001) with the level of cell death. Thus this assay offers the possibility to discriminate the minimal non-toxic dose of the individual transfection method. In addition this work suggests that the ECIS-device bears the feasibility to transfer this assay to multiple other cytotoxicological questions. PMID:20875729

  2. Toward a Real-Time Measurement-Based System for Estimation of Helicopter Engine Degradation Due to Compressor Erosion

    NASA Technical Reports Server (NTRS)

    Litt, Jonathan S.; Simo, Donald L.

    2007-01-01

    This paper presents a preliminary demonstration of an automated health assessment tool, capable of real-time on-board operation using existing engine control hardware. The tool allows operators to discern how rapidly individual turboshaft engines are degrading. As the compressor erodes, performance is lost, and with it the ability to generate power. Thus, such a tool would provide an instant assessment of the engine s fitness to perform a mission, and would help to pinpoint any abnormal wear or performance anomalies before they became serious, thereby decreasing uncertainty and enabling improved maintenance scheduling. The research described in the paper utilized test stand data from a T700-GE-401 turboshaft engine that underwent sand-ingestion testing to scale a model-based compressor efficiency degradation estimation algorithm. This algorithm was then applied to real-time Health Usage and Monitoring System (HUMS) data from a T700-GE-701C to track compressor efficiency on-line. The approach uses an optimal estimator called a Kalman filter. The filter is designed to estimate the compressor efficiency using only data from the engine s sensors as input.

  3. Multiplex Real-Time PCR Assays that Measure the Abundance of Extremely Rare Mutations Associated with Cancer

    PubMed Central

    Vargas, Diana Y.; Kramer, Fred Russell; Tyagi, Sanjay; Marras, Salvatore A. E.

    2016-01-01

    We describe the use of “SuperSelective” primers that enable the detection and quantitation of somatic mutations whose presence relates to cancer diagnosis, prognosis, and therapy, in real-time PCR assays that can potentially analyze rare DNA fragments present in blood samples (liquid biopsies). The design of these deoxyribonucleotide primers incorporates both a relatively long “5' anchor sequence” that hybridizes strongly to target DNA fragments, and a very short, physically and functionally separate, “3' foot sequence” that is perfectly complementary to the mutant target sequence, but mismatches the wild-type sequence. As few as ten mutant fragments can reliably be detected in the presence of 1,000,000 wild-type fragments, even when the difference between the mutant and the wild type is only a single nucleotide polymorphism. Multiplex PCR assays employing a set of SuperSelective primers, and a corresponding set of differently colored molecular beacon probes, can be used in situations where the different mutations, though occurring in different cells, are located in the same codon. These non-symmetric real-time multiplex PCR assays contain limited concentrations of each SuperSelective primer, thereby enabling the simultaneous determination of each mutation’s abundance by comparing its threshold value to the threshold value of a reference gene present in the sample. PMID:27244445

  4. Multiplex Real-Time PCR Assays that Measure the Abundance of Extremely Rare Mutations Associated with Cancer.

    PubMed

    Vargas, Diana Y; Kramer, Fred Russell; Tyagi, Sanjay; Marras, Salvatore A E

    2016-01-01

    We describe the use of "SuperSelective" primers that enable the detection and quantitation of somatic mutations whose presence relates to cancer diagnosis, prognosis, and therapy, in real-time PCR assays that can potentially analyze rare DNA fragments present in blood samples (liquid biopsies). The design of these deoxyribonucleotide primers incorporates both a relatively long "5' anchor sequence" that hybridizes strongly to target DNA fragments, and a very short, physically and functionally separate, "3' foot sequence" that is perfectly complementary to the mutant target sequence, but mismatches the wild-type sequence. As few as ten mutant fragments can reliably be detected in the presence of 1,000,000 wild-type fragments, even when the difference between the mutant and the wild type is only a single nucleotide polymorphism. Multiplex PCR assays employing a set of SuperSelective primers, and a corresponding set of differently colored molecular beacon probes, can be used in situations where the different mutations, though occurring in different cells, are located in the same codon. These non-symmetric real-time multiplex PCR assays contain limited concentrations of each SuperSelective primer, thereby enabling the simultaneous determination of each mutation's abundance by comparing its threshold value to the threshold value of a reference gene present in the sample. PMID:27244445

  5. Real time measurement of plasma macroscopic parameters on RFX-mod using a limited set of sensors

    NASA Astrophysics Data System (ADS)

    Kudlacek, Ondrej; Zanca, Paolo; Finotti, Claudio; Marchiori, Giuseppe; Cavazzana, Roberto; Marrelli, Lionello

    2015-10-01

    A method to estimate the plasma boundary and global parameters such as βp+li/2 and the edge safety factor q95 is described. The method is based on poloidal flux extrapolation in the vacuum region between the plasma and the magnetic measurements, and it is efficient and accurate even if a limited set of sensors is used. The discrepancy between the plasma boundary provided by this method and the boundary computed by the Grad-Shafranov solver MAXFEA is lower than 8 mm in all the considered cases. Moreover, the method is robust against the noise level present in the RFX-mod measurements. The difference between the estimated global parameters and the MAXFEA simulation results is lower than 4%. The method was finally implemented in the RFX-mod shape control system, working at 5 kHz cycle frequency, to provide a reliable set of plasma-wall distances (gaps) used as feedback signals. Experimental results obtained in one year of RFX-mod operation are shown.

  6. A scientific database for real-time Neutron Monitor measurements - taking Neutron Monitors into the 21st century

    NASA Astrophysics Data System (ADS)

    Steigies, Christian

    2012-07-01

    The Neutron Monitor Database project, www.nmdb.eu, has been funded in 2008 and 2009 by the European Commission's 7th framework program (FP7). Neutron monitors (NMs) have been in use worldwide since the International Geophysical Year (IGY) in 1957 and cosmic ray data from the IGY and the improved NM64 NMs has been distributed since this time, but a common data format existed only for data with one hour resolution. This data was first distributed in printed books, later via the World Data Center ftp server. In the 1990's the first NM stations started to record data at higher resolutions (typically 1 minute) and publish in on their webpages. However, every NM station chose their own format, making it cumbersome to work with this distributed data. In NMDB all European and some neighboring NM stations came together to agree on a common format for high-resolution data and made this available via a centralized database. The goal of NMDB is to make all data from all NM stations available in real-time. The original NMDB network has recently been joined by the Bartol Research Institute (Newark DE, USA), the National Autonomous University of Mexico and the North-West University (Potchefstroom, South Africa). The data is accessible to everyone via an easy to use webinterface, but expert users can also directly access the database to build applications like real-time space weather alerts. Even though SQL databases are used today by most webservices (blogs, wikis, social media, e-commerce), the power of an SQL database has not yet been fully realized by the scientific community. In training courses, we are teaching how to make use of NMDB, how to join NMDB, and how to ensure the data quality. The present status of the extended NMDB will be presented. The consortium welcomes further data providers to help increase the scientific contributions of the worldwide neutron monitor network to heliospheric physics and space weather.

  7. Real-Time Simulation

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Coryphaeus Software, founded in 1989 by former NASA electronic engineer Steve Lakowske, creates real-time 3D software. Designer's Workbench, the company flagship product, is a modeling and simulation tool for the development of both static and dynamic 3D databases. Other products soon followed. Activation, specifically designed for game developers, allows developers to play and test the 3D games before they commit to a target platform. Game publishers can shorten development time and prove the "playability" of the title, maximizing their chances of introducing a smash hit. Another product, EasyT, lets users create massive, realistic representation of Earth terrains that can be viewed and traversed in real time. Finally, EasyScene software control the actions among interactive objects within a virtual world. Coryphaeus products are used on Silican Graphics workstation and supercomputers to simulate real-world performance in synthetic environments. Customers include aerospace, aviation, architectural and engineering firms, game developers, and the entertainment industry.

  8. Real-Time PCR

    NASA Astrophysics Data System (ADS)

    Evrard, A.; Boulle, N.; Lutfalla, G. S.

    Over the past few years there has been a considerable development of DNA amplification by polymerase chain reaction (PCR), and real-time PCR has now superseded conventional PCR techniques in many areas, e.g., the quantification of nucleic acids and genotyping. This new approach is based on the detection and quantification of a fluorescent signal proportional to the amount of amplicons generated by PCR. Real-time detection is achieved by coupling a thermocycler with a fluorimeter. This chapter discusses the general principles of quantitative real-time PCR, the different steps involved in implementing the technique, and some examples of applications in medicine. The polymerase chain reaction (PCR) provides a way of obtaining a large number of copies of a double-stranded DNA fragment of known sequence. This DNA amplification technique, developed in 1985 by K. Mullis (Cetus Corporation), saw a spectacular development over the space of a few years, revolutionising the methods used up to then in molecular biology. Indeed, PCR has many applications, such as the detection of small amounts of DNA, cloning, and quantitative analysis (assaying), each of which will be discussed further below.

  9. Design of a wireless telemetric backpack device for real-time in vivo measurement of pressure-volume loops in conscious ambulatory rats.

    PubMed

    Raghavan, Karthik; Kottam, Anil T G; Valvano, Jonathan W; Pearce, John A

    2008-01-01

    Pressure - Volume (PV) analysis is the de facto standard for assessing myocardial function. Conductance based methods have been used for the past 27 years to generate instantaneous left ventricular (LV) volume signal. Our research group has developed the instrumentation and the algorithm for obtaining PV loops based on the measurement of real - time admittance magnitude and phase from the LV of anaesthetized mice and rats. In this study, the instrumentation will be integrated into an ASIC (Application Specific Integrated Circuit) and a backpack device will be designed along with this ASIC. This will enable measurement of real-time in vivo P-V loops from conscious and ambulatory rats, useful for both acute and chronic studies. PMID:19162825

  10. Real-Time Measurements of Ethane for Source Attribution of Methane Plumes from Oil and Gas Facilities

    NASA Astrophysics Data System (ADS)

    Yacovitch, T. I.; Floerchinger, C.; Roscioli, J. R.; Herndon, S.; Fortner, E.; Knighton, W. B.; Petron, G.; Sweeney, C.; Karion, A.; Kofler, J.; Iglesias, G.; Zavala, M. A.; Molina, L. T.

    2013-12-01

    The Aerodyne Mobile Lab has conducted several recent studies of the methane emissions from Oil and Gas facilities at varying stages of production: well-heads; processing facilities; and compressor stations. Accurate quantification of methane emission rates are can be complicated by other local sources, notably livestock and microbial production. Methane emissions from oil and gas facilities are always accompanied by small amounts of ethane, while biogenic plumes contain no ethane. A prototype ethane spectrometer based on the Aerodyne-Mini chassis, has been deployed to oil and gas facilities in the Veracruz region of Mexico, as part of the 2013 Short-Lived Climate-Forcing project, and during ground-based measurements in the Barnett Shale in Texas as part of the Barnett Oil and Gas Observation Study. These results suggest a source-dependence in the ethane-to-methane ratio in oil and gas emissions. The results will be contrasted with 13CH4 methane isotope ratios determined using Aerodyne's Methane-Dual instrument. The limits and advantages of ethane-methane ratios and methane isotopes will be discussed. In the current instrumentation, the precision of determined ethane-to-methane ratios in a single plume encounter exceeds the analogous carbon isotope quantification.

  11. Near real-time monitoring of volcanic surface deformation from GPS measurements at Long Valley Caldera, California

    NASA Astrophysics Data System (ADS)

    Ji, Kang Hyeun; Herring, Thomas A.; Llenos, Andrea L.

    2013-03-01

    Long Valley Caldera in eastern California is an active volcanic area and has shown continued unrest in the last three decades. We have monitored surface deformation from Global Positioning System (GPS) data by using a projection method that we call Targeted Projection Operator (TPO). TPO projects residual time series with secular rates and periodic terms removed onto a predefined spatial pattern. We used the 2009-2010 slow deflation as a target spatial pattern. The resulting TPO time series shows a detailed deformation history including the 2007-2009 inflation, the 2009-2010 deflation, and a recent inflation that started in late-2011 and is continuing at the present time (November 2012). The recent inflation event is about four times faster than the previous 2007-2009 event. A Mogi source of the recent event is located beneath the resurgent dome at about 6.6 km depth at a rate of 0.009 km3/yr volume change. TPO is simple and fast and can provide a near real-time continuous monitoring tool without directly looking at all the data from many GPS sites in this potentially eruptive volcanic system.

  12. Near real-time monitoring of volcanic surface deformation from GPS measurements at Long Valley Caldera, California

    USGS Publications Warehouse

    Ji, Kang Hyeun; Herring, Thomas A.; Llenos, Andrea L.

    2013-01-01

    Long Valley Caldera in eastern California is an active volcanic area and has shown continued unrest in the last three decades. We have monitored surface deformation from Global Positioning System (GPS) data by using a projection method that we call Targeted Projection Operator (TPO). TPO projects residual time series with secular rates and periodic terms removed onto a predefined spatial pattern. We used the 2009–2010 slow deflation as a target spatial pattern. The resulting TPO time series shows a detailed deformation history including the 2007–2009 inflation, the 2009–2010 deflation, and a recent inflation that started in late-2011 and is continuing at the present time (November 2012). The recent inflation event is about four times faster than the previous 2007–2009 event. A Mogi source of the recent event is located beneath the resurgent dome at about 6.6 km depth at a rate of 0.009 km3/yr volume change. TPO is simple and fast and can provide a near real-time continuous monitoring tool without directly looking at all the data from many GPS sites in this potentially eruptive volcanic system.

  13. Real-time refinement of subthalamic nucleus targeting using Bayesian decision-making on the root mean square measure.

    PubMed

    Moran, Anan; Bar-Gad, Izhar; Bergman, Hagai; Israel, Zvi

    2006-09-01

    The subthalamic nucleus (STN) is a major target for treatment of advanced Parkinson's disease patients undergoing deep brain stimulation surgery. Microelectrode recording (MER) is used in many cases to identify the target nucleus. A real-time procedure for identifying the entry and exit points of the STN would improve the outcome of this targeting procedure. We used the normalized root mean square (NRMS) of a short (5 seconds) MER sampled signal and the estimated anatomical distance to target (EDT) as the basis for this procedure. Electrode tip location was defined intraoperatively by an expert neurophysiologist to be before, within, or after the STN. Data from 46 trajectories of 27 patients were used to calculate the Bayesian posterior probability of being in each of these locations, given RMS-EDT pair values. We tested our predictions on each trajectory using a bootstrapping technique, with the rest of the trajectories serving as a training set and found the error in predicting the STN entry to be (mean +/- SD) 0.18 +/- 0.84, and 0.50 +/- 0.59 mm for STN exit point, which yields a 0.30 +/- 0.28 mm deviation from the expert's target center. The simplicity and computational ease of RMS calculation, its spike sorting-independent nature and tolerance to electrode parameters of this Bayesian predictor, can lead directly to the development of a fully automated intraoperative physiological procedure for the refinement of imaging estimates of STN borders. PMID:16763982

  14. Measurements by Mail: Satellite-Controlled Balloons for Making Real-Time Atmospheric Observations Anywhere on Earth

    NASA Astrophysics Data System (ADS)

    Voss, P. B.

    2008-12-01

    While most of the atmosphere is only a few tens of kilometers overhead, gaining access to this critical region of the earth system is notoriously difficult. Aircraft have been highly successful as atmospheric research platforms but their use can be limited by high costs, complex logistics, and need for ground-support infrastructure. While small Unmanned Aerial Systems (UAS) carry far fewer instruments, they promise to overcome some of these limitations, especially if regulatory and air safety issues can be resolved. Here we describe five years of development on a new type of unmanned platform that can be flown with far fewer restrictions than current UAS. This altitude-controlled balloon can be mailed to collaborators almost anywhere in the world, launched within hours, and flown remotely from our laboratory via satellite link. It can be commanded to perform soundings, track atmospheric layers, or navigate divergent wind fields over periods ranging from days to potentially weeks; meteorological and chemical observations from the balloon are processed on the ground and distributed via the internet in near real time. These controlled balloons have been used in several recent atmospheric research campaigns and are now providing new possibilities for long-distance collaboration, low-cost deployments, and research in previously inaccessible parts of the lower atmosphere.

  15. Comparison of Three Real-Time Measurement Methods for Airborne Ultrafine Particles in the Silicon Alloy Industry.

    PubMed

    Kero, Ida Teresia; Jørgensen, Rikke Bramming

    2016-01-01

    The aim of this study was to compare the applicability and the correlation between three commercially available instruments capable of detection, quantification, and characterization of ultrafine airborne particulate matter in the industrial setting of a tapping area in a silicon alloy production plant. The number concentration of ultrafine particles was evaluated using an Electric Low Pressure Impactor (ELPI(TM)), a Fast Mobility Particle Sizer (FMPS(TM)), and a Condensation Particle Counter (CPC). The results are discussed in terms of particle size distribution and temporal variations linked to process operations. The instruments show excellent temporal covariation and the correlation between the FMPS and ELPI is good. The advantage of the FMPS is the excellent time- and size resolution of the results. The main advantage of the ELPI is the possibility to collect size-fractionated samples of the dust for subsequent analysis by, for example, electron microscopy. The CPC does not provide information about the particle size distribution and its correlation to the other two instruments is somewhat poor. Nonetheless, the CPC gives basic, real-time information about the ultrafine particle concentration and can therefore be used for source identification. PMID:27598180

  16. Quantitative Real-Time Measurements of DNA Hybridization with Alkylated Non-Oxidized Silicon Nanowires in Electrolyte Solution

    PubMed Central

    Bunimovich, Yuri L.; Shin, Young Shik; Yeo, Woon-Seok; Amori, Michael; Kwong, Gabriel

    2013-01-01

    The quantitative, real time detection of single stranded oligonucleotides with silicon nanowires (SiNWs) in physiologically relevant electrolyte solution is demonstrated. Debye screening of the hybridization event is minimized by utilizing electrostatically adsorbed primary DNA on an amine-terminated NW surface. Two surface functionalization chemistries are compared: an amine terminated siloxane monolayer on the native SiO2 surface of the SiNW, and an amine terminated alkyl monolayer grown directly on a hydrogen-terminated SiNW surface. The SiNWs without the native oxide exhibit improved solution-gated field-effect transistor characteristics and a significantly enhanced sensitivity to single stranded DNA detection, with an accompanying two orders of magnitude improvement in the dynamic range of sensing. A model for the detection of analyte by SiNW sensors is developed and utilized to extract DNA binding kinetic parameters. Those values are directly compared with values obtained by the standard method of surface plasmon resonance (SPR), and demonstrated to be similar. The nanowires, however, are characterized by higher detection sensitivity. The implication is that Si NWs can be utilized to quantitate the solution phase concentration of biomolecules at low concentrations. This work also demonstrates the importance of surface chemistry for optimizing biomolecular sensing with silicon nanowires. PMID:17165787

  17. Real-time soil flux measurements and calculations with CRDS + Soil Flux Processor: comparison among flux algorithms and derivation of whole system error

    NASA Astrophysics Data System (ADS)

    Alstad, K. P.; Venterea, R. T.; Tan, S. M.; Saad, N.

    2015-12-01

    Understanding chamber-based soil flux model fitting and measurement error is key to scaling soils GHG emissions and resolving the primary uncertainties in climate and management feedbacks at regional scales. One key challenge is the selection of the correct empirical model applied to soil flux rate analysis in chamber-based experiments. Another challenge is the characterization of error in the chamber measurement. Traditionally, most chamber-based N2O and CH4 measurements and model derivations have used discrete sampling for GC analysis, and have been conducted using extended chamber deployment periods (DP) which are expected to result in substantial alteration of the pre-deployment flux. The development of high-precision, high-frequency CRDS analyzers has advanced the science of soil flux analysis by facilitating much shorter DP and, in theory, less chamber-induced suppression of the soil-atmosphere diffusion gradient. As well, a new software tool developed by Picarro (the "Soil Flux Processor" or "SFP") links the power of Cavity Ring-Down Spectroscopy (CRDS) technology with an easy-to-use interface that features flexible sample-ID and run-schemes, and provides real-time monitoring of chamber accumulations and environmental conditions. The SFP also includes a sophisticated flux analysis interface which offers a user-defined model selection, including three predominant fit algorithms as default, and an open-code interface for user-composed algorithms. The SFP is designed to couple with the Picarro G2508 system, an analyzer which simplifies soils flux studies by simultaneously measuring primary GHG species -- N2O, CH4, CO2 and H2O. In this study, Picarro partners with the ARS USDA Soil & Water Management Research Unit (R. Venterea, St. Paul), to examine the degree to which the high-precision, high-frequency Picarro analyzer allows for much shorter DPs periods in chamber-based flux analysis, and, in theory, less chamber-induced suppression of the soil

  18. Geophysical Measurements for Real-time Monitoring of Biogeochemical Processes for Improvement of Soil Engineering Properties and Subsurface Environmental Conditions (Invited)

    NASA Astrophysics Data System (ADS)

    DeJong, J. T.

    2013-12-01

    A variety of biogeochemical processes, from inorganic mineral precipitation, to bio-film formation, to bio-gas generation, are being investigated as alternative methods to improve soil engineering properties and subsurface environmental conditions. Every process applied in a geotechnical or geoenvironmental application requires the ability to monitor the progression of treatment non-destructively and in real-time. Geophysical methods have been shown effective to monitor temporally and map spatially soil improvement. Results from seismic velocity (compression and shear wave) and resistivity measurements obtained on 1-D, 2-D, and 3-D experiments at scales ranging from bench-top to field scale will be presented. Shear wave velocity will be demonstrated to be most effective in monitoring microbially induced calcite precipitation (MICP) in sands while compression wave velocity will be used to monitor desaturation through bio-gas formation. Finally, the implications of these results for real-time monitoring during field-scale applications will be discussed.

  19. Real-time predictions of drug release and end point detection of a coating operation by in-line near infrared measurements.

    PubMed

    Gendre, Claire; Boiret, Mathieu; Genty, Muriel; Chaminade, Pierre; Pean, Jean Manuel

    2011-12-15

    The aim of this work was to carry out real-time near infrared (NIR) predictions of drug release from sustained release coated tablets and to determine end point of coating operation. In-line measurements were ensured by implementation of a NIR probe inside a pan coater. Tablets were coated using a functional aqueous dispersion of ethylcellulose blended with PVA-PEG graft copolymer to obtain a controlled drug release dosage form over 16h. Samples were collected at regular intervals and subjected to a standardized curing step. Percentages of released drug at 4h, 8h and 12h were selected to describe the controlled drug release of cured tablets. These dissolution criteria were used as reference values to calibrate NIR spectral information and to develop three partial least squares regressions. Low predictive errors of 1.7%, 1.9% and 1.5%, respectively, were obtained. The coating operation was stopped while desired dissolution criteria were achieved, corresponding to a coating level around 10%. The present study demonstrated that real-time NIR measurements could be performed on non-finished drug products to predict dissolution properties of cured coated tablets. This novel and innovative approach fulfils the expectations of ICH Q8 guideline on pharmaceutical development, in terms of process understanding and process analytical technology (PAT) control strategy. This approach should be however adapted to curing operation to allow a real-time release testing. PMID:21983094

  20. Direct real-time quantitative PCR for measurement of host-cell residual DNA in therapeutic proteins.

    PubMed

    Peper, Grit; Fankhauser, Alexander; Merlin, Thomas; Roscic, Ana; Hofmann, Matthias; Obrdlik, Petr

    2014-11-01

    Real-time quantitative PCR (qPCR) is important for quantification of residual host cell DNA (resDNA) in therapeutic protein preparations. Typical qPCR protocols involve DNA extraction steps complicating sample handling. Here, we describe a "direct qPCR" approach without DNA extraction. To avoid interferences of DNA polymerase with a therapeutic protein, proteins in the samples were digested with proteinase K (PK) in the presence of sodium dodecyl sulfate (SDS). Tween 20 and NaCl were included to minimize precipitation of therapeutic proteins in the PK/SDS mix. After PK treatment, the solution was applied directly for qPCR. Inhibition of DNA polymerase by SDS was prevented by adding 2% (v/v) of Tween 20 to the final qPCR mix. The direct qPCR approach was evaluated for quantification of resDNA in therapeutic proteins manufactured in Chinese hamster ovary (CHO) host cells. First, direct qPCR was compared with qPCR applied on purified DNA ("extraction qPCR"). For both qPCRs, the same CHO-specific primers and probes were used. Comparable residual DNA levels were detected with both PCR approaches in purified and highly concentrated drug proteins as well as in in-process-control samples. Finally, the CHO-specific direct qPCR protocol was validated according to ICH guidelines and applied for 25 different therapeutic proteins. The specific limits of quantification were 0.1-0.8ppb for 24 proteins, and 2.0ppb for one protein. General applicability of the direct qPCR was demonstrated by applying the sample preparation protocol for quantification of resDNA in therapeutic proteins manufactured in other hosts such as Escherichia coli and mouse cells. PMID:25151232

  1. Head movement compensation in real-time magnetoencephalographic recordings

    PubMed Central

    Little, Graham; Boe, Shaun; Bardouille, Timothy

    2014-01-01

    Neurofeedback- and brain-computer interface (BCI)-based interventions can be implemented using real-time analysis of magnetoencephalographic (MEG) recordings. Head movement during MEG recordings, however, can lead to inaccurate estimates of brain activity, reducing the efficacy of the intervention. Most real-time applications in MEG have utilized analyses that do not correct for head movement. Effective means of correcting for head movement are needed to optimize the use of MEG in such applications. Here we provide preliminary validation of a novel analysis technique, real-time source estimation (rtSE), that measures head movement and generates corrected current source time course estimates in real-time. rtSE was applied while recording a calibrated phantom to determine phantom position localization accuracy and source amplitude estimation accuracy under stationary and moving conditions. Results were compared to off-line analysis methods to assess validity of the rtSE technique. The rtSE method allowed for accurate estimation of current source activity at the source-level in real-time, and accounted for movement of the source due to changes in phantom position. The rtSE technique requires modifications and specialized analysis of the following MEG work flow steps.•Data acquisition•Head position estimation•Source localization•Real-time source estimation This work explains the technical details and validates each of these steps. PMID:26150963

  2. Comparative evaluation of immunohistochemistry and real-time PCR for measuring proinflammatory cytokines gene expression in livers of rats treated with gold nanoparticles.

    PubMed

    Khan, Haseeb A; Ibrahim, Khalid E; Khan, Ayaat; Alrokayan, Salman H; Alhomida, Abdullah S; Lee, Yong-Kyu

    2016-08-01

    Gold nanoparticles (GNPs) possess promising applications in targeted drug delivery and controlled release of a variety of chemical agents. However, the immunocompatibility of GNPs is poorly understood. After exposure, GNPs preferentially tend to accumulate is liver, where they induce an acute phase proinflammatory response. We therefore compared the two techniques, immunohistochemistry and real-time PCR for measuring the protein and mRNA expressions of IL-1β, IL-6 and TNF-α in liver of rats after intraperitoneal injections (5μg/animal) of 10 and 50nm diameter GNPs for 1 and 5days. The results showed that both 10nm and 50nm GNPs induced an acute phase expression of proinflammatory cytokines that receded on day 5. The proinflammatory response on day 1 was comparatively more severe with 50nm GNPs than 10nm GNPs. A comparative evaluation between immunostaining and real-time PCR showed that the latter technique is more sensitive as it could detect the cytokines mRNA expression in control samples as well. This could be partly attributed to the amplification strategy used in real-time PCR and partly to the variations in the half lives of cytokines mRNA and their resulting proteins. PMID:27287986

  3. Development of a Real-Time Repeated-Measures Assessment Protocol to Capture Change over the Course of a Drinking Episode

    PubMed Central

    Luczak, Susan E.; Rosen, I. Gary; Wall, Tamara L.

    2015-01-01

    Aims: We report on the development of a real-time assessment protocol that allows researchers to assess change in BrAC, alcohol responses, behaviors, and contexts over the course of a drinking event. Method: We designed a web application that uses timed text messages (adjusted based on consumption pattern) containing links to our website to obtain real-time participant reports; camera and location features were also incorporated into the protocol. We used a transdermal alcohol sensor device along with software we designed to convert transdermal data into estimated BrAC. Thirty-two college students completed a laboratory session followed by a 2-week field trial. Results: Results for the web application indicated we were able to create an effective tool for obtaining repeated measures real-time drinking data. Participants were willing to monitor their drinking behavior with the web application, and this did not appear to strongly affect drinking behavior during, or 6 weeks following, the field trial. Results for the transdermal device highlighted the willingness of participants to wear the device despite some discomfort, but technical difficulties resulted in limited valid data. Conclusion: The development of this protocol makes it possible to capture detailed assessment of change over the course of naturalistic drinking episodes. PMID:25568142

  4. Real-time and integrated measurement of potential human exposure to particle-bound polycyclic aromatic hydrocarbons (PAHs) from aircraft exhaust.

    PubMed Central

    Childers, J W; Witherspoon, C L; Smith, L B; Pleil, J D

    2000-01-01

    We used real-time monitors and low-volume air samplers to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. We used three types of photoelectric aerosol sensors (PASs) to measure real-time concentrations of particle-bound PAHs in a break room, downwind from a C-130H aircraft during a four-engine run-up test, in a maintenance hangar, in a C-130H aircraft cargo bay during cargo-drop training, downwind from aerospace ground equipment (AGE), and in a C-130H aircraft cargo bay during engine running on/off (ERO) loading and backup exercises. Two low-volume air samplers were collocated with the real-time monitors for all monitoring events except those in the break room and during in-flight activities. Total PAH concentrations in the integrated-air samples followed a general trend: downwind from two AGE units > ERO-loading exercise > four-engine run-up test > maintenance hangar during taxi and takeoff > background measurements in maintenance hangar. Each PAH profile was dominated by naphthalene, the alkyl-substituted naphthalenes, and other PAHs expected to be in the vapor phase. We also found particle-bound PAHs, such as fluoranthene, pyrene, and benzo[a]pyrene in some of the sample extracts. During flight-related exercises, total PAH concentrations in the integrated-air samples were 10-25 times higher than those commonly found in ambient air. Real-time monitor mean responses generally followed the integrated-air sample trends. These monitors provided a semiquantitative temporal profile of ambient PAH concentrations and showed that PAH concentrations can fluctuate rapidly from a baseline level < 20 to > 4,000 ng/m(3) during flight-related activities. Small handheld models of the PAS monitors exhibited potential for assessing incidental personal exposure to particle-bound PAHs in engine exhaust and for serving as

  5. Real-time and integrated measurement of potential human exposure to particle-bound polycyclic aromatic hydrocarbons (PAHs) from aircraft exhaust.

    PubMed

    Childers, J W; Witherspoon, C L; Smith, L B; Pleil, J D

    2000-09-01

    We used real-time monitors and low-volume air samplers to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. We used three types of photoelectric aerosol sensors (PASs) to measure real-time concentrations of particle-bound PAHs in a break room, downwind from a C-130H aircraft during a four-engine run-up test, in a maintenance hangar, in a C-130H aircraft cargo bay during cargo-drop training, downwind from aerospace ground equipment (AGE), and in a C-130H aircraft cargo bay during engine running on/off (ERO) loading and backup exercises. Two low-volume air samplers were collocated with the real-time monitors for all monitoring events except those in the break room and during in-flight activities. Total PAH concentrations in the integrated-air samples followed a general trend: downwind from two AGE units > ERO-loading exercise > four-engine run-up test > maintenance hangar during taxi and takeoff > background measurements in maintenance hangar. Each PAH profile was dominated by naphthalene, the alkyl-substituted naphthalenes, and other PAHs expected to be in the vapor phase. We also found particle-bound PAHs, such as fluoranthene, pyrene, and benzo[a]pyrene in some of the sample extracts. During flight-related exercises, total PAH concentrations in the integrated-air samples were 10-25 times higher than those commonly found in ambient air. Real-time monitor mean responses generally followed the integrated-air sample trends. These monitors provided a semiquantitative temporal profile of ambient PAH concentrations and showed that PAH concentrations can fluctuate rapidly from a baseline level < 20 to > 4,000 ng/m(3) during flight-related activities. Small handheld models of the PAS monitors exhibited potential for assessing incidental personal exposure to particle-bound PAHs in engine exhaust and for serving as

  6. Temporal averaging of phase measurements in the presence of spurious phase drift - Application to phase-stepped real-time holographic interferometry

    NASA Technical Reports Server (NTRS)

    Ovryn, B.; Haacke, E. M.

    1993-01-01

    A technique that compensates for low spatial frequency spurious phase changes during an interference experiment is developed; it permits temporal averaging of multiple-phase measurements, made before and after object displacement. The method is tested with phase-stepped real-time holographic interferometry applied to cantilever bending of a piezoelectric bimorph ceramic. Results indicate that temporal averaging of the corrected data significantly reduces the white noise in a phase measurement without incurring systematic errors or sacrificing spatial resolution. White noise is reduced from 3 deg to less than 1 deg using these methods.

  7. [Real time 3D echocardiography].

    PubMed

    Bauer, F; Shiota, T; Thomas, J D

    2001-07-01

    Three-dimensional representation of the heart is an old concern. Usually, 3D reconstruction of the cardiac mass is made by successive acquisition of 2D sections, the spatial localisation and orientation of which require complex guiding systems. More recently, the concept of volumetric acquisition has been introduced. A matricial emitter-receiver probe complex with parallel data processing provides instantaneous of a pyramidal 64 degrees x 64 degrees volume. The image is restituted in real time and is composed of 3 planes (planes B and C) which can be displaced in all spatial directions at any time during acquisition. The flexibility of this system of acquisition allows volume and mass measurement with greater accuracy and reproducibility, limiting inter-observer variability. Free navigation of the planes of investigation allows reconstruction for qualitative and quantitative analysis of valvular heart disease and other pathologies. Although real time 3D echocardiography is ready for clinical usage, some improvements are still necessary to improve its conviviality. Then real time 3D echocardiography could be the essential tool for understanding, diagnosis and management of patients. PMID:11494630

  8. [Real time 3D echocardiography

    NASA Technical Reports Server (NTRS)

    Bauer, F.; Shiota, T.; Thomas, J. D.

    2001-01-01

    Three-dimensional representation of the heart is an old concern. Usually, 3D reconstruction of the cardiac mass is made by successive acquisition of 2D sections, the spatial localisation and orientation of which require complex guiding systems. More recently, the concept of volumetric acquisition has been introduced. A matricial emitter-receiver probe complex with parallel data processing provides instantaneous of a pyramidal 64 degrees x 64 degrees volume. The image is restituted in real time and is composed of 3 planes (planes B and C) which can be displaced in all spatial directions at any time during acquisition. The flexibility of this system of acquisition allows volume and mass measurement with greater accuracy and reproducibility, limiting inter-observer variability. Free navigation of the planes of investigation allows reconstruction for qualitative and quantitative analysis of valvular heart disease and other pathologies. Although real time 3D echocardiography is ready for clinical usage, some improvements are still necessary to improve its conviviality. Then real time 3D echocardiography could be the essential tool for understanding, diagnosis and management of patients.

  9. Real time automated inspection

    DOEpatents

    Fant, Karl M.; Fundakowski, Richard A.; Levitt, Tod S.; Overland, John E.; Suresh, Bindinganavle R.; Ulrich, Franz W.

    1985-01-01

    A method and apparatus relating to the real time automatic detection and classification of characteristic type surface imperfections occurring on the surfaces of material of interest such as moving hot metal slabs produced by a continuous steel caster. A data camera transversely scans continuous lines of such a surface to sense light intensities of scanned pixels and generates corresponding voltage values. The voltage values are converted to corresponding digital values to form a digital image of the surface which is subsequently processed to form an edge-enhanced image having scan lines characterized by intervals corresponding to the edges of the image. The edge-enhanced image is thresholded to segment out the edges and objects formed by the edges are segmented out by interval matching and bin tracking. Features of the objects are derived and such features are utilized to classify the objects into characteristic type surface imperfections.

  10. Real time automated inspection

    DOEpatents

    Fant, K.M.; Fundakowski, R.A.; Levitt, T.S.; Overland, J.E.; Suresh, B.R.; Ulrich, F.W.

    1985-05-21

    A method and apparatus are described relating to the real time automatic detection and classification of characteristic type surface imperfections occurring on the surfaces of material of interest such as moving hot metal slabs produced by a continuous steel caster. A data camera transversely scans continuous lines of such a surface to sense light intensities of scanned pixels and generates corresponding voltage values. The voltage values are converted to corresponding digital values to form a digital image of the surface which is subsequently processed to form an edge-enhanced image having scan lines characterized by intervals corresponding to the edges of the image. The edge-enhanced image is thresholded to segment out the edges and objects formed by the edges by interval matching and bin tracking. Features of the objects are derived and such features are utilized to classify the objects into characteristic type surface imperfections. 43 figs.

  11. Real-Time Parameter Estimation in the Frequency Domain

    NASA Technical Reports Server (NTRS)

    Morelli, Eugene A.

    2000-01-01

    A method for real-time estimation of parameters in a linear dynamic state-space model was developed and studied. The application is aircraft dynamic model parameter estimation from measured data in flight. Equation error in the frequency domain was used with a recursive Fourier transform for the real-time data analysis. Linear and nonlinear simulation examples and flight test data from the F-18 High Alpha Research Vehicle were used to demonstrate that the technique produces accurate model parameter estimates with appropriate error bounds. Parameter estimates converged in less than one cycle of the dominant dynamic mode, using no a priori information, with control surface inputs measured in flight during ordinary piloted maneuvers. The real-time parameter estimation method has low computational requirements and could be implemented

  12. Microelectrical Impedance Spectroscopy for the Differentiation between Normal and Cancerous Human Urothelial Cell Lines: Real-Time Electrical Impedance Measurement at an Optimal Frequency

    PubMed Central

    Park, Yangkyu; Kim, Hyeon Woo; Yun, Joho; Seo, Seungwan; Park, Chang-Ju; Lee, Jeong Zoo; Lee, Jong-Hyun

    2016-01-01

    Purpose. To distinguish between normal (SV-HUC-1) and cancerous (TCCSUP) human urothelial cell lines using microelectrical impedance spectroscopy (μEIS). Materials and Methods. Two types of μEIS devices were designed and used in combination to measure the impedance of SV-HUC-1 and TCCSUP cells flowing through the channels of the devices. The first device (μEIS-OF) was designed to determine the optimal frequency at which the impedance of two cell lines is most distinguishable. The μEIS-OF trapped the flowing cells and measured their impedance at a frequency ranging from 5 kHz to 1 MHz. The second device (μEIS-RT) was designed for real-time impedance measurement of the cells at the optimal frequency. The impedance was measured instantaneously as the cells passed the sensing electrodes of μEIS-RT. Results. The optimal frequency, which maximized the average difference of the amplitude and phase angle between the two cell lines (p < 0.001), was determined to be 119 kHz. The real-time impedance of the cell lines was measured at 119 kHz; the two cell lines differed significantly in terms of amplitude and phase angle (p < 0.001). Conclusion. The μEIS-RT can discriminate SV-HUC-1 and TCCSUP cells by measuring the impedance at the optimal frequency determined by the μEIS-OF. PMID:26998490

  13. Calibration method for a photoacoustic system for real time source apportionment of light absorbing carbonaceous aerosol based on size distribution measurements

    NASA Astrophysics Data System (ADS)

    Utry, Noemi; Ajtai, Tibor; Pinter, Mate; Orvos, Peter I.; Szabo, Gabor; Bozoki, Zoltan

    2016-04-01

    In this study, we introduce a calibration method with which sources of light absorbing carbonaceous particulate matter (LAC) can be apportioned in real time based on multi wavelength optical absorption measurements with a photoacoustic system. The method is primary applicable in wintry urban conditions when LAC is dominated by traffic and biomass burning. The proposed method was successfully tested in a field campaign in the city center of Szeged, Hungary during winter time where the dominance of traffic and wood burning aerosol has been experimentally demonstrated earlier. With the help of the proposed calibration method a relationship between the measured Aerosol Angström Exponent (AAE) and the number size distribution can be deduced. Once the calibration curve is determined, the relative strength of the two pollution sources can be deduced in real time as long as the light absorbing fraction of PM is exclusively related to traffic and wood burning. This assumption is indirectly confirmed in the presented measurement campaign by the fact that the measured size distribution is composed of two unimodal size distributions identified to correspond to traffic and wood burning aerosols. The proposed method offers the possibility of replacing laborious chemical analysis with simple in-situ measurement of aerosol size distribution data.

  14. Real-time 3D shape measurement with digital stripe projection by Texas Instruments Micro Mirror Devices DMD

    NASA Astrophysics Data System (ADS)

    Frankowski, Gottfried; Chen, Mai; Huth, Torsten

    2000-03-01

    The fast, contact-free and highly precise shape measurement of technical objects is of key importance in the scientific- technological area as well as the area of practical measurement technology. The application areas of contact- free surface measurement extend across widely different areas, e.g., the automation of production processes, the measurement and inspection of components in microsystem technology or the fast 3D in-vivo measurement of human skin surfaces in cosmetics and medical technology. This paper describes methodological and technological possibilities as well as measurement technology applications for fast optical 3D shape measurements using micromirror-based high-velocity stripe projection. Depending on the available projector and camera facilities, it will be possible to shoot and evaluate compete 3D surface profiles within only a few milliseconds.

  15. Real time in vivo imaging and measurement of serine protease activity in the mouse hippocampus using a dedicated complementary metal-oxide semiconductor imaging device.

    PubMed

    Ng, David C; Tamura, Hideki; Tokuda, Takashi; Yamamoto, Akio; Matsuo, Masamichi; Nunoshita, Masahiro; Ishikawa, Yasuyuki; Shiosaka, Sadao; Ohta, Jun

    2006-09-30

    The aim of the present study is to demonstrate the application of complementary metal-oxide semiconductor (CMOS) imaging technology for studying the mouse brain. By using a dedicated CMOS image sensor, we have successfully imaged and measured brain serine protease activity in vivo, in real-time, and for an extended period of time. We have developed a biofluorescence imaging device by packaging the CMOS image sensor which enabled on-chip imaging configuration. In this configuration, no optics are required whereby an excitation filter is applied onto the sensor to replace the filter cube block found in conventional fluorescence microscopes. The fully packaged device measures 350 microm thick x 2.7 mm wide, consists of an array of 176 x 144 pixels, and is small enough for measurement inside a single hemisphere of the mouse brain, while still providing sufficient imaging resolution. In the experiment, intraperitoneally injected kainic acid induced upregulation of serine protease activity in the brain. These events were captured in real time by imaging and measuring the fluorescence from a fluorogenic substrate that detected this activity. The entire device, which weighs less than 1% of the body weight of the mouse, holds promise for studying freely moving animals. PMID:16542733

  16. Tissue distribution and real-time fluorescence measurement of a tumor-targeted nanodevice by a two photon optical fiber fluorescence probe

    NASA Astrophysics Data System (ADS)

    Thomas, Thommey P.; Ye, Jing Yong; Yang, Chu-Sheng; Myaing, Monthiri; Majoros, Istvan J.; Kotlyar, Alina; Cao, Zhengyi; Norris, Theodore B.; Baker, James R., Jr.

    2006-02-01

    Real-time fluorescence measurement in deep tumors in live animals (or humans) by conventional methods has significant challenges. We have developed a two-photon optical fiber fluorescence (TPOFF) probe as a minimally invasive technique for quantifying fluorescence in solid tumors in live mice. Here we demonstrate TPOFF for real-time measurements of targeted drug delivery dynamics to tumors in live mice. 50-femtosecond laser pulses at 800 nm were coupled into a single mode optical fiber and delivered into the tumor through a 27-gauge needle. Fluorescence was collected back through the same fiber, filtered, and detected with photon counting. Biocompatible dendrimer-based nanoparticles were used for targeted delivery of fluorescent materials into tumors. Dendrimers with targeting agent folic acid and fluorescent reporter 6-TAMRA (G5-6T-FA) were synthesized. KB cell tumors expressing high levels of FA receptors were developed in SCID mice. We initially demonstrated the specific uptake of the targeted conjugates into tumor, kidney and liver, using the TPOFF probe. The tumor fluorescence was then taken in live mice at 30 min, 2 h and 24 h with the TPOFF probe. G5-6T-FA accumulated in the tumor with maximum mean levels reaching 673 +/- 67 nM at the 2 h time point. In contrast, the levels of a control, non-targeted conjugate (G5-6T) at 2 h reached a level of only 136 +/- 28 nM in tumors, and decrease quickly. This indicates that the TPOFF probe can be used as a minimally invasive detection system for quantifying the specific targeting of a fluorescent nanodevice on a real-time basis.

  17. REAL-TIME INDOOR AND OUTDOOR MEASUREMENTS OF BLACK CARBON IN AN OCCUPIED HOUSE: AN EXAMINATION OF SOURCES

    EPA Science Inventory

    Black carbon (BC) was measured every five minutes for two years (May, 1998 to May 2000) inside and immediately outside a northern Virginia house (suburban Washington, DC) occupied by two nonsmokers. Two Aethalometers TM, which measure BC by optical transmission through a quart...

  18. Real-Time Parameter Estimation Using Output Error

    NASA Technical Reports Server (NTRS)

    Grauer, Jared A.

    2014-01-01

    Output-error parameter estimation, normally a post- ight batch technique, was applied to real-time dynamic modeling problems. Variations on the traditional algorithm were investigated with the goal of making the method suitable for operation in real time. Im- plementation recommendations are given that are dependent on the modeling problem of interest. Application to ight test data showed that accurate parameter estimates and un- certainties for the short-period dynamics model were available every 2 s using time domain data, or every 3 s using frequency domain data. The data compatibility problem was also solved in real time, providing corrected sensor measurements every 4 s. If uncertainty corrections for colored residuals are omitted, this rate can be increased to every 0.5 s.

  19. Real-time glutamate measurements in the putamen of awake rhesus monkeys using an enzyme-based human microelectrode array prototype

    PubMed Central

    Stephens, Michelle L.; Pomerleau, Francois; Huettl, Peter; Gerhardt, Greg A.; Zhang, Zhiming

    2009-01-01

    Commonly used for research studies in the central nervous system, microdialysis has revealed a link between dysregulation of the excitatory neurotransmitter glutamate and ischemia and seizure, however limitations like slow temporal resolution have stalled the advancement of microdialysis as a diagnostic tool. We have developed and extensively characterized an enzyme-based microelectrode array technology for second-by-second in vivo amperometric measurements of glutamate in the mammalian CNS. The current studies demonstrated the ability of a human microelectrode array prototype (SG-2) to measure tonic and phasic glutamate neurotransmission in the putamen of unanesthetized non-human primates. We also showed that the SG-2 remains functional following sterilization. Ability to monitor dynamic changes in glutamate in real-time may assist in the development of clinical algorithms to potentially alert care-providers prior to onset of overt ischemia or seizure, or provide neurosurgeons with real-time measurements of rapid changes in extracellular glutamate which could help guide surgical procedures or aid in interventional strategies. PMID:19850078

  20. Real-time displacement measurement system using phase-shifted optical pulse interferometry: Application to a seismic observation system

    NASA Astrophysics Data System (ADS)

    Yoshida, Minoru; Hirayama, Yoshiharu; Takahara, Atsushi; Kashi, Motofumi; Takeuchi, Keiji; Ikeda, Toshiharu; Hirai, Fumio; Mizuno, Yosuke; Nakamura, Kentaro; Kimura, Hitoshi; Ino, Norio; Inoue, Wataru

    2016-02-01

    We developed a method of detecting incident light levels on the oscillator surfaces and light pulses that include two interfering pulses with a phase shift of π/2 (phase-shifted optical pulse interferometry). This system enables the measurement of displacements greatly exceeding the half wavelength of the laser. Moreover, it allows measurements at multiple locations with a single optical fiber for using optical pulses. In this study, we conducted an interference experiment using 30 ns optical pulses and transmitted them at 1 µs intervals. We confirmed that the above two measurements are possible. Furthermore, from the data of the oscillator used for verification, we showed that measurements on the order of nanometers are possible. Since this method does not require a power supply to the oscillator, its widespread applications in physical exploration can be expected.

  1. Real-Time Measurement of Oil Circulation Ratio in CO2 Heat Pump System Using Optical Method

    NASA Astrophysics Data System (ADS)

    Takigawa, Ryusuke; Shimizu, Takao; Matsusaka, Yukio; Gao, Lei; Honda, Tomohiro

    The lubricating oil in the refrigerant flow in a CO2 heat pump system has a great influence on cycle performance. In order to measure the OCR (Oil circulation ratio), a mixing chamber and a visual vessel were installed at the outlet of the gas-cooler. By mixing the oil and refrigerant, the liquid mixture of oil and refrigerant becomes cloudy at the outlet of the gas-cooler. By measuring the infrared ray transmittance of the oil-refrigerant liquid mixture, it was found that the transmittance decreases with an increase in the oil circulation ratio. For this reason, it is found that, in spite of immiscible refrigerant and oil, the measurement of the oil circulation ratio is possible by measuring the transmittance of infrared ray at the outlet of the gas-cooler.

  2. Real-Time Field-Based Water Vapor Isotope Measurements with a CRDS Analyzer: Probing Cropland Evapotranspiration

    NASA Astrophysics Data System (ADS)

    van Pelt, Aaron; Williams, David; Mayr, Leo; Sun, Wei

    2010-05-01

    While stable isotope techniques have been previously applied to partition evapotranspiration (ET) fluxes in crops, it has only recently become possible to take in-situ, long-term, continuous (every 10 seconds) measurements of stable water vapor isotopologues. A Picarro water vapor isotope analyzer based on cavity ringdown spectroscopy (CRDS) was recently deployed at China's National Experimental Station for Precision Agriculture during the FAO/IAEA 2nd Research Coordination Meeting of a five-year Coordinated Research Project on "Managing Irrigation Water to Enhance Crop Productivity under Water-Limiting Conditions using Nuclear Techniques" involving the participation of 15 participants from 15 different countries. Measurements were conducted continuously over several days, sampling from five different heights above a corn field. The continuous measurements by the Picarro analyzer were complimented by additional measurements from the same sampling points, wherein the vapor was cryogenically trapped for later laboratory quantification of the water isotopologues. Stable isotope measurements were taken concurrently with conventional ET flux measurements. The isotope analyses can allow the partitioning of ET into its components: soil evaporation and leaf transpiration. Once daily, during the vapor measurements, liquid water isotope standards were measured by the Picarro analyzer using its included autosampler and subsequently used to calibrate the vapor-phase data. This presentation will describe the analyzer and sampling system in detail as well as discuss important factors that were incorporated into the data analysis to ensure accuracy. Field data will be presented along with these accuracy estimates as well as comparison of the vapor-phase results with the off-line liquid analysis of the cryogenically-trapped vapor.

  3. Accurate measurement of unsteady state fluid temperature

    NASA Astrophysics Data System (ADS)

    Jaremkiewicz, Magdalena

    2016-07-01

    In this paper, two accurate methods for determining the transient fluid temperature were presented. Measurements were conducted for boiling water since its temperature is known. At the beginning the thermometers are at the ambient temperature and next they are immediately immersed into saturated water. The measurements were carried out with two thermometers of different construction but with the same housing outer diameter equal to 15 mm. One of them is a K-type industrial thermometer widely available commercially. The temperature indicated by the thermometer was corrected considering the thermometers as the first or second order inertia devices. The new design of a thermometer was proposed and also used to measure the temperature of boiling water. Its characteristic feature is a cylinder-shaped housing with the sheath thermocouple located in its center. The temperature of the fluid was determined based on measurements taken in the axis of the solid cylindrical element (housing) using the inverse space marching method. Measurements of the transient temperature of the air flowing through the wind tunnel using the same thermometers were also carried out. The proposed measurement technique provides more accurate results compared with measurements using industrial thermometers in conjunction with simple temperature correction using the inertial thermometer model of the first or second order. By comparing the results, it was demonstrated that the new thermometer allows obtaining the fluid temperature much faster and with higher accuracy in comparison to the industrial thermometer. Accurate measurements of the fast changing fluid temperature are possible due to the low inertia thermometer and fast space marching method applied for solving the inverse heat conduction problem.

  4. Real time infrared aerosol analyzer

    DOEpatents

    Johnson, Stanley A.; Reedy, Gerald T.; Kumar, Romesh

    1990-01-01

    Apparatus for analyzing aerosols in essentially real time includes a virtual impactor which separates coarse particles from fine and ultrafine particles in an aerosol sample. The coarse and ultrafine particles are captured in PTFE filters, and the fine particles impact onto an internal light reflection element. The composition and quantity of the particles on the PTFE filter and on the internal reflection element are measured by alternately passing infrared light through the filter and the internal light reflection element, and analyzing the light through infrared spectrophotometry to identify the particles in the sample.

  5. Real-time measurement of individual occupational radon exposures in tombs of the Valley of the Kings, Egypt.

    PubMed

    Gruber, E; Salama, E; Rühm, W

    2011-03-01

    The active radon exposure meter developed recently at the German Research Center for Environmental Health (Helmholtz Zentrum München) was used to measure radon concentrations in 12 tombs located in the Valley of the Kings, Egypt. Radon concentrations in air between 50 ± 7 and 12 100 ± 600 Bq m(-3) were obtained. The device was also used to measure individual radon exposures of those persons working as safeguards inside the tombs. For a measurement time of 2-3 d, typical individual radon exposures ranged from 1800 ± 400 to 240 000 ± 13 000 Bq h m(-3), depending on the duration of measurement and radon concentration in the different tombs. Based on current ICRP dose conversion conventions for workers and on equilibrium factors published in the literature for these tombs, individual effective dose rates that range from 1.5 ± 0.3 to 860 ± 50 µSv d(-1) were estimated. If it is assumed that the climatic conditions present at the measurement campaign persist for about half a year, in this area, then effective doses up to ∼ 66 mSv could be estimated for half a year, for some of the safeguards of tombs where F-values were known. To reduce the exposure of the safeguards, some recommendations are proposed. PMID:21183552

  6. Low cost "laserless" FTIR spectrometer on the farm for real-time nitrous oxide soil emission measurements.

    PubMed

    Haugholt, Karl Henrik; Lacolle, Matthieu; O'Farrell, Marion; Honne, Atle; Bakke, Kari Anne Hestnes; Lundon, Aina

    2013-02-01

    A low-cost Fourier transform infrared (FTIR) instrument was developed where the traditional He-Ne reference laser was replaced by a low-cost linear encoder. An RMS sampling error of less than 20 nm was achieved by oversampling both the interferogram and the encoder signal and then resampling the interferogram using a correction table for the encoder. A gas calibration model was developed for the system, which was chosen to have a stroke length of 21 mm and, thereby, a resolution of 0.4 cm(-1) after apodization. The instrument was mounted on a vehicle and employed in an agricultural field test for measuring soil emissions, in particular nitrous oxide (N(2)O). The concentration of N(2)O was measured with a root mean squared error of 6 ppb. The results compared well with lab-based gas chromatography measurements. PMID:23385946

  7. Evaluation of carcass, live, and real-time ultrasound measures in feedlot cattle: I. Assessment of sex and breed effects.

    PubMed

    Hassen, A; Wilson, D E; Rouse, G H

    1999-02-01

    Carcass and live-animal measures from 1,029 cattle were collected at the Iowa State University Rhodes and McNay research farms over a 6-yr period. Data were from bull, heifer, and steer progeny of composite, Angus, and Simmental sires mated to three composite lines of dams. The objectives of this study were to estimate genetic parameters for carcass traits, to evaluate effects of sex and breed of sire on growth models (curves), and to suggest a strategy to adjust serially measured data to a constant age end point. Estimation of genetic parameters using a three-trait mixed model showed differences between bulls and steers in estimates of h2 and genetic correlations. Heritability for carcass weight, percentage of retail product, retail product weight, fat thickness, and longissimus muscle area from bull data were .43, .04, .46, .05, and .21, respectively. The corresponding values for steer data were in order of .32, .24, .40, .42, and .07, respectively. Analysis of serially measured fat thickness, longissimus muscle area, body weight, hip height, and ultrasound percentage of intramuscular fat using a repeated measures model showed a limitation in the use of growth models based on pooled data. In further evaluation of regression parameters using a linear mixed model analysis, sex and breed of sire showed an important (P < .05) effect on intercept and slope values. Regression of serially measured traits on age within animal showed a relatively larger R2 (62 to 98%) and a smaller root mean square error (RMSE, .09 to 8.85) as compared with R2 (0 to 58%) and RMSE (.31 to 67.9) values when the same model was used on pooled data. We concluded that regression parameters from a within-animal regression of a serially measured trait on age, averaged by sex and breed, are the best choice in describing growth and adjusting data to a constant age end point. PMID:10100654

  8. Real-time measurements of atmospheric CO using a continuous-wave room temperature quantum cascade laser based spectrometer.

    PubMed

    Li, Jingsong; Parchatka, Uwe; Königstedt, Rainer; Fischer, Horst

    2012-03-26

    A compact, mobile mid-infrared laser spectrometer based on a thermoelectrically (TE) cooled continuous-wave room temperature quantum cascade laser and TE-cooled detectors has been newly developed to demonstrate the applicability of high sensitivity and high precision measurements of atmospheric CO. Performance of the instrument was examined with periodic measurements of reference sample and ambient air at 1 Hz sampling rate and a 1-hourly calibration cycle. The typical precision evaluated from replicate measurements of reference sample over the course of 66-h is 1.41 ppbv. With the utilization of wavelet filtering to improve the spectral SNR and minimize the dispersion of concentration values, a better precision of 0.88 ppbv and a lower detection limit of ~0.4 ppbv with sub-second averaging time have been achieved without reducing the fast temporal response. Allan variance analysis indicates a CO measurement precision of ~0.28 ppbv for optimal integration time of approximate 50 s. The absolute accuracy is limited by the calibration gas standard. This completely thermoelectrically cooled system shows the capability of long-term, unattended and continuous operation at room temperature without complicated cryogenic cooling. PMID:22453438

  9. Performance of solid-state sensors for continuous, real-time measurement of soil CO2 concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent advances in sensor technology provide a robust capability for continuous measurement of soil gases. The performance of solid-state CO2 sensors (Model GMM220 series, Vaisala, Finland) was evaluated in laboratory, greenhouse, and irrigated wheat (Triticum aestivum L.). In ambient CO2 concentrat...

  10. USE OF REMPI-TOFMS FOR REAL-TIME MEASUREMENT OF TRACE AROMATICS DURING OPERATION OF AIRCRAFT GROUND EQUIPMENT

    EPA Science Inventory

    Emissions of aromatic air toxics from aircraft ground equipment were measured with a resonance enhanced multiphoton ionization—time of flight mass spectrometry (REMPI-TOFMS) system consisting of a pulsed solid state laser for photoionization and a TOFMS for mass discrimination. T...

  11. Basic atmospheric measurements via Arduino Uno microcontroller with commercially available sensors towards simple real-time weather forecasting for increased classroom engagement

    NASA Astrophysics Data System (ADS)

    Eckel, Ryan; Tanner, Meghan; Senevirathne, Indrajith

    Makers, engineers and the applied physics community have adapted Arduino microcontrollers due to their versatility, robustness and cost effectiveness. Arduino microcontroller environment coupled with commercially available sensors have been used to systematically measure, record and analyze temperature, humidity and barometric pressure for building a simplified weather station for subsequent educational purposes. This data will become available in classroom settings for real-time analysis towards simple weather forecasting. Setup was assembled via breadboard, wire and simple soldering with an Arduino Uno ATmega328P microcontroller connected to a PC. The microcontroller was programmed with Arduino Software while the bootloader was used to upload the code. Commercial DHT22 humidity and temperature sensor, and BMP180 barometric pressure sensor were used to obtain relative humidity, temperature and the barometric pressure. A weather resistant enclosure protected the system while stable real-time data measurements were obtained, and uploaded onto the PC. The data was used to predict atmospheric conditions and lifting condensation level (LCL). Discussion will focus on capabilities and limitations of these systems and corresponding teaching aspects. Lock Haven University Nanotechnology Program.

  12. Development and experimental evaluation of a thermography measurement system for real-time monitoring of comfort and heat rate exchange in the built environment

    NASA Astrophysics Data System (ADS)

    Revel, G. M.; Sabbatini, E.; Arnesano, M.

    2012-03-01

    A measurement system based on infrared (IR) thermovision technique (ITT) is developed for real-time estimation of room thermal variations and comfort conditions in office-type environment as a part of a feasibility study in the EU FP7 project ‘INTUBE’. An IR camera installed on the ceiling allows thermal image acquisition and post-processing is performed to derive mean surface temperatures, number of occupants and presence of other heat sources (e.g. computer) through detecting algorithms. A lumped parameter model of the room, developed in the Matlab/Simulink environment, receives as input the information extracted from image processing to compute room exchanged heat rate, air temperature and thermal comfort (PMV). The aim is to provide in real time the room thermal balance and comfort information for energy-saving purposes in an improved way with respect to traditional thermostats. Instantaneous information can be displayed for the users or eventually used for automatic HVAC control. The system is based on custom adaptation of a surveillance low-cost IR system with dedicated radiometric calibration. Experimental results show average absolute discrepancies in the order of 0.4 °C between calculated and measured air temperature during a time period of a day. A sensitivity analysis is performed in order to identify main uncertainty sources.

  13. Real-time total integrated scattering measurements on the Mir spacecraft to evaluate sample degradation in space.

    PubMed

    Hadaway, J B; Ahmad, A; Pezzaniti, J L; Chipman, R A; Wilkes, D R; Hummer, L L; Crandall, D G; Bennett, J M

    2001-06-01

    An instrument to measure total integrated scattering (TIS) in space was built as part of the Optical Properties Monitor instrument package and flown on the Russian Mir Space Station in a low Earth orbit. TIS at two wavelengths was measured in space at approximately weekly intervals from 29 April to 26 December 1997 and telemetered to Earth during the mission. Of the 20 TIS samples, 13 are described here to illustrate the performance of the TIS instrument. These include ten optical samples and three thermal control samples. Two optical samples and one thermal control sample were severely degraded by atomic oxygen. All samples received a light dusting of particles during the mission and an additional heavier layer after the samples returned to Earth. The initial brassboard instrument and the validation tests of the flight instrument are also described. PMID:18357293

  14. Real-time measurement of dual-wavelength laser-induced fluorescence spectra of individual aerosol particles.

    PubMed

    Huang, Hermes C; Pan, Yong-Le; Hill, Steven C; Pinnick, Ronald G; Chang, Richard K

    2008-10-13

    We report the development of an in-situ aerosol detection system capable of rapidly measuring dual-wavelength laser-induced fluorescence spectra of single particles on the fly using a single spectrometer and a single 32-anode photomultiplier array. We demonstrate the capability of this system with both reference samples and outdoor air. We present spectra from separate excitation wavelengths from the same particle that demonstrate improved discrimination capability compared with only using one excitation wavelength. PMID:18852760

  15. Using Real-time Event Tracking Sensitivity Analysis to Overcome Sensor Measurement Uncertainties of Geo-Information Management in Drilling Disasters

    NASA Astrophysics Data System (ADS)

    Tavakoli, S.; Poslad, S.; Fruhwirth, R.; Winter, M.

    2012-04-01

    of such reservoirs; both in onshore regions as well as in offshore regions. Drilling a well is always guided by technical, economic and security constraints to prevent crew, equipment and environment from injury, damage and pollution. Although risk assessment and local practice provides a high degree of security, uncertainty is given by the behaviour of the formation which may cause crucial situations at the rig. To overcome such uncertainties real-time sensor measurements form a base to predict and thus prevent such crises, the proposed method supports the identification of the data necessary for that.

  16. Improved instrumentation for near-real-time measurement of reactive hydrocarbons, NO{sub 2}, and peroxyacyl nitrates.

    SciTech Connect

    Drayton, P. J.; Blazer, C. A.; Gaffney, J. S.; Marley, N. A.

    1999-10-06

    The measurement of reactive hydrocarbons and associated nitrogen oxides, NO{sub 2}, and peroxyacyl nitrates (PANs) is of key importance to unraveling the complex chemistries involved in daytime photochemical oxidant formation and nighttime chemistry driven by the nitrate radical. Recent work has demonstrated that chemiluminescent reactions of ozone with hydrocarbons (and the temperature dependence of the reactions) can be used as a means of detecting a wide variety of organic compounds in the gas phase with sensitivity comparable to or better than that of the conventional flame ionization detection method (Marley and Gaffney, 1998). We have implemented a new design and built a new instrument to evaluate this approach for the monitoring of alkenes. This instrument makes use of a computer-controlled photon-counting system with a reaction chamber operated at room temperature. Signals are compared to those for an ethene standard to estimate relative reactivity. The instrument is described in detail here, along with a new version of a luminol-based chemiluminescence detection system with fast gas chromatography for measurement of NO{sub 2} and PANs. The photon-counting system, the reaction chamber, and the luminol detection system have been combined on one instrument rack for field use on both ground-based and aircraft platforms. Data presented show the response times of the instruments and indicate applications for examining reactive hydrocarbon emissions from both vegetation and anthropogenic sources. In addition, the luminol chemiluminescence instrument was field tested, and the data obtained are compared with data from a commercial NO{sub x} analyzer. Preliminary results demonstrating the potential use of this instrumentation for rapid measurement of key tropospheric trace species are presented and discussed.

  17. Real-time high-resolution PC-based system for measurement of errors on compact disks

    NASA Astrophysics Data System (ADS)

    Tehranchi, Babak; Howe, Dennis G.

    1994-10-01

    Hardware and software utilities are developed to directly monitor the Eight-to-Fourteen (EFM) demodulated data bytes at the input of a CD player's Cross-Interleaved Reed-Solomon Code (CIRC) block decoder. The hardware is capable of identifying erroneous data with single-byte resolution in the serial data stream read from a Compact Disc by a CDD 461 Philips CD-ROM drive. In addition, the system produces graphical maps that show the physical location of the measured errors on the entire disc, or via a zooming and planning feature, on user selectable local disc regions.

  18. Accurate shear measurement with faint sources

    SciTech Connect

    Zhang, Jun; Foucaud, Sebastien; Luo, Wentao E-mail: walt@shao.ac.cn

    2015-01-01

    For cosmic shear to become an accurate cosmological probe, systematic errors in the shear measurement method must be unambiguously identified and corrected for. Previous work of this series has demonstrated that cosmic shears can be measured accurately in Fourier space in the presence of background noise and finite pixel size, without assumptions on the morphologies of galaxy and PSF. The remaining major source of error is source Poisson noise, due to the finiteness of source photon number. This problem is particularly important for faint galaxies in space-based weak lensing measurements, and for ground-based images of short exposure times. In this work, we propose a simple and rigorous way of removing the shear bias from the source Poisson noise. Our noise treatment can be generalized for images made of multiple exposures through MultiDrizzle. This is demonstrated with the SDSS and COSMOS/ACS data. With a large ensemble of mock galaxy images of unrestricted morphologies, we show that our shear measurement method can achieve sub-percent level accuracy even for images of signal-to-noise ratio less than 5 in general, making it the most promising technique for cosmic shear measurement in the ongoing and upcoming large scale galaxy surveys.

  19. Estimation of Genetic Parameters for Real-time Ultrasound Measurements for Hanwoo Cows at Different Ages and Pregnancy Status

    PubMed Central

    Lee, J. H.; Lee, Y. M.; Oh, S.-H.; Son, H. J.; Jeong, D. J.; Whitley, Niki; Kim, J. J.

    2014-01-01

    The purpose of this study was to estimate genetic parameters of ultrasound measurements for longissimus dorsi muscle area (LMA), backfat thickness (BFT), and marbling score (MS) in Hanwoo cows (N = 3,062) at the ages between 18 and 42 months. Data were collected from 100 Hanwoo breeding farms in Gyeongbuk province, Korea, in 2007 and 2008. The cows were classified into four different age groups, i.e. 18 to 22 months (the first pregnancy period), 23 to 27 (the first parturition), 28 to 32 (the second pregnancy), and 33 to 42 (the second parturition), respectively. For each age group, a multi-trait animal model was used to estimate variance components and heritabilities of the three traits. The averages of LMA, BFT, and MS measurements across the cows of all age groups were 50.1 cm2, 4.62 mm, and 3.04, respectively and heritability estimates were 0.09, 0.10, and 0.08 for the respective traits. However, when the data were analyzed in different age groups, heritability estimates of LMA and BFT were 0.24 and 0.47, respectively, for the cows of 18 to 22 months of age, and 0.21 for MS in the 28 to 32 months old cows. When the cows of all age groups were used, the estimates of genetic (phenotypic) correlations were 0.43 (0.35), −0.06 (0.34) and 0.21 (0.32) between LMA and BFT, LMA and MS, and BFT and MS, respectively. However, in the cow age group between 28 and 32 (18 and 22) months, the estimates of genetic (phenotypic) correlations were 0.05 (0.29), −0.15 (0.24) and 0.38 (0.24), for the respective pairs of traits. These results suggest that genetic, environmental, and phenotypic variations differ depending on cow age, such that care must be taken when ultrasound measurements are applied to selection of cows for meat quality. PMID:25049938

  20. First real-time measurement of the evolving 2H/1H ratio during water evaporation from plant leaves.

    PubMed

    Kerstel, Erik R T; Wel, L Gerko van der; Meijer, Harro A J

    2005-09-01

    We have studied the temporal behaviour of the deuterium isotope ratio of water vapour emerging from a freshly cut plant leaf placed in a dry nitrogen atmosphere. The leaf material was placed directly inside the sample gas cell of the stable isotope ratio infrared spectrometer. At the reduced pressure ( approximately 40 mbar) inside the cell, the appearance of water evaporating from the leaf is easily probed by the spectrometer, as well as the evolving isotope ratios, with a precision of about 1 per thousand. The demonstration experiment we describe measures the 2H/1H isotope ratio only, but the experiment can be easily extended to include the 18O/16O and 17O/16O isotope ratios. Plant leaf water isotope ratios provide important information towards quantification of the different components in the ecosystem water and carbon dioxide exchange. PMID:16126516

  1. Development of wireless communication system in real-time internal radiation dose measurement system using magnetic field

    NASA Astrophysics Data System (ADS)

    Sato, Fumihiro; Shinohe, Kohta; Takura, Tetsuya; Matsuki, Hidetoshi; Yamada, Syogo; Sato, Tadakuni

    2009-04-01

    In radiation therapy, excessive radiation occurs because the actual delivered dose to the tumor is unknown. To overcome this problem, we need a system in which the delivered dose is measured inside the body, and the dose data are transmitted from the inside to the outside of the body. In this study, a wireless communication system, using magnetic fields was studied, and an internal circuit for obtaining radiation dose data from an x-ray detector was examined. As a result, a communication distance of 200 mm was obtained. An internal circuit was developed, and a signal transmission experiment was performed using the wireless communication system. As a result, the radiation dose data from an x-ray detector was transmitted over a communication distance of 200 mm, and the delivered dose was determined from the received signal.

  2. Measurement of patient imaging dose for real-time kilovoltage x-ray intrafraction tumour position monitoring in prostate patients

    NASA Astrophysics Data System (ADS)

    Crocker, James K.; Aun Ng, Jin; Keall, Paul J.; Booth, Jeremy T.

    2012-05-01

    The dose for image-based motion monitoring of prostate tumours during radiotherapy delivery has not been established. This study aimed to provide quantitative analysis and optimization of the fluoroscopic patient imaging dose during radiotherapy for IMRT and VMAT treatments using standard and hypofractionated treatment schedules. Twenty-two patients with type T1c N0/M0 prostate cancer and three implanted fiducial markers were considered. Minimum field sizes encompassing all fiducial markers plus a 7.5 mm motion margin were determined for each treatment beam, each patient and the complete cohort. Imaging doses were measured for different field sizes and depths in a phantom at 75 and 120 kV. Based on these measurements, the patient imaging doses were then estimated according to beam-on time for clinical settings. The population minimum field size was 5.3 × 6.1 cm2, yielding doses of 406 and 185 mGy over the course of an IMRT treatment for 75 kV (10 mAs) and 120 kV (1.04 mAs) imaging respectively, at 1 Hz. The imaging dose was reduced by an average of 28% and 32% by adopting patient-specific and treatment-beam-specific field sizes respectively. Standard fractionation VMAT imaging doses were 37% lower than IMRT doses over a complete treatment. Hypofractionated IMRT stereotactic body radiotherapy (SBRT) and VMAT SBRT imaging doses were 58% and 76% lower than IMRT doses respectively. The patient dose for kilovoltage intrafraction monitoring of the prostate was quantified. Tailoring imaging field sizes to specific patients yielded a significant reduction in the imaging dose, as did adoption of faster treatment modalities such as VMAT.

  3. Real-time formation evaluation using a well-site data management system to integrate MWD, surface measurements, and enhanced mud logging data

    SciTech Connect

    Whittaker, A.; Brooks, A.; Dowsett, R.; MacPherson, J.; Nigh, E.

    1986-04-01

    With the advent of measurement while drilling (MWD), a new source of quantitative data became available during the drilling process. The availability of wireline log-type data while drilling has led to a need that traditional mud-logging methods be augmented and enhanced to provide more quantitative correlative data sources and benchmark standards for the lithologic normalization of MWD data. Together these data can be integrated within a single well-site data base to provide effective formation evaluation while the drilling process continues. The data base may be so structured that later available data, such as wireline logs, may be input to provide confirmation and refinement of real-time evaluations. Similarly, the data base may be primed with geophysical and geological pronoses prior to drilling. Case histories show the effective real-time determination of true total and effective porosities, fluid saturations, and estimates of formation characteristics, such as mineralogy and permeability. In each example, when departures between early and late data sets occur (e.g., wireline logs or formation tests), the data variation results from changes in downhole conditions, and the data can be used to enhance formation evaluation by adding a dynamic component.

  4. Real time Measurement of Nitrate in Stream Water for a Paired Basin Study within the Choptank River Watershed, Maryland, USA.

    NASA Astrophysics Data System (ADS)

    McCarty, Greg

    2013-04-01

    For this study, a robust water quality monitoring system was designed to measure nitrate and sediment using a commercially available UV-Vis spectrometer probe. To increase reliability for monitoring highly dynamic small streams and reduce susceptibility to vandalism in public place installations, an innovative the monitoring system was implemented around the use of a flow cell attachment for the probe with automated stream water sample delivery using a peristaltic pump. This permitted all instrumentation and electronics to be housed in secure enclosures with maximum flexibility in sampling location in the dynamic stream cross section. Monitoring systems were successfully deployed at two USGS stream gauge stations located at public parks near the towns of Ruthsburg and Greensboro within the Choptank Watershed which established a paired basin comparison of water quality. Both basins have a mixed land use of cropland in largely corn - soybean rotation and forests containing extensive wetland complexes. The basins have very similar amounts of cropland area but the Greensboro basin contains more wetlands and cropland formed from wetland drainage. Monitoring data has shown that the Ruthsburg basin exports about 25% more nitrate per area of cropland than the Greensboro basin. These results are indicative of greater landscape processing of nitrate in the Greensboro basin due to greater prevalence of wetlands and poorly drained soils in crop production.

  5. Real-time measurement of volcanic SO2 emissions: Validation of a new UV correlation spectrometer (FLYSPEC)

    USGS Publications Warehouse

    Horton, K.A.; Williams-Jones, G.; Garbeil, H.; Elias, T.; Sutton, A.J.; Mouginis-Mark, P.; Porter, J.N.; Clegg, S.

    2006-01-01

    A miniaturized, lightweight and low-cost UV correlation spectrometer, the FLYSPEC, has been developed as an alternative for the COSPEC, which has long been the mainstay for monitoring volcanic sulfur dioxide fluxes. Field experiments have been conducted with the FLYSPEC at diverse volcanic systems, including Masaya (Nicaragua), Poa??s (Costa Rica), Stromboli, Etna and Vulcano (Italy), Villarica (Chile) and Kilauea (USA). We present here those validation measurements that were made simultaneously with COSPEC at Kilauea between March 2002 and February 2003. These experiments, with source emission rates that ranged from 95 to 1,560 t d-1, showed statistically identical results from both instruments. SO2 path-concentrations ranged from 0 to >1,000 ppm-m with average correlation coefficients greater than r2=0.946. The small size and low cost create the opportunity for FLYSPEC to be used in novel deployment modes that have the potential to revolutionize the manner in which volcanic and industrial monitoring is performed. ?? Springer-Verlag 2006.

  6. A new, non-destructive, real-time measurement technique of the surface area of aerogel during synthesis

    NASA Astrophysics Data System (ADS)

    Shen, Yang; Lee, Jeongseop A.; Halperin, W. P.

    We have developed a new method of measuring surface area of silica aerogel during the synthesis stage using a standard pulsed NMR setup. The applicability of this method can be extended to a much broader type of chemical reactions yielding a rigid porous condensate whose surface relaxation rate differs substantially from its surrounding liquids. The number of various chemical species involved in the reaction poses little to no limitation to its applicability owing to the physics in the fast exchange limit. This is the main distinguishing feature from a conventional NMR or infrared spectroscopy method in which individual chemical bondings from various reaction intermediaries are tracked in time which is often difficult if not impossible due to complex reactions. The result from this technique yields a surface area that is analogous to the result from a well-established BET (Brunauer-Emmett-Teller) technique, but without the need for extraction or supercritical extraction of the porous medium. This work was supported by the DOE BES under grants No. DE-FG02-05ER46248.

  7. Quantum cascade laser based sensor for in situ and real time atmospheric trace gases (CO and N2O) measurements

    NASA Astrophysics Data System (ADS)

    Li, Jingsong; Parchatka, Uwe; Fischer, Horst

    2013-04-01

    In addition to the primary greenhouse gases carbon dioxide (CO2) and methane (CH4), several other atmospheric trace gases are radiatively active, and thereby can also contribute to a greenhouse warming of the lower atmosphere directly or indirectly. Nitrous oxide (N2O) is a greenhouse gas with a global warming potential about 200-300 times that of CO2. Carbon monoxide (CO) is not considered a direct greenhouse gas, mostly because it does not absorb terrestrial thermal IR energy strongly enough. However, CO plays an important role in the oxidative chemistry of Earth's atmosphere, since it is a key trace gas for controlling the budget and distribution of the hydroxyl (OH) radical, which exerts a controlling influence on the gas phase chemistry of many atmospheric species [1]. Therefore, there is a critical need to identify sources and sinks of N2O and CO in order to better understand their impact on global climate change [2]. We present a fast, compact, and precise sensor based-on a novel thermoelectrically (TE) cooled quantum cascade laser (QCL) operating at near-room temperature in CW (continuous-wave) mode for simultaneous detection of atmospheric N2O and CO. The technique is based on atmospheric absorption of these trace species in the mid-infrared region near 4.56 µm, using a single QC laser source and two TE-cooled infrared detectors. Wavelength modulation spectroscopy with second harmonic detection technique in conjunction with a compact multi-pass absorption cell has been employed to demonstrate highly sensitive and precise measurements. CO and N2O at ambient concentration levels are detected simultaneously with a high temporal response (< 1s). Preliminary results (Laboratory investigation and field application) of the sensor's performance will be presented. This completely TE-cooled system shows the capability of long-term, unattended and continuous operation at room temperature without complicated cryogenic cooling [3]. [1] J. A. Logan, M. J. Prather, S. C

  8. Real-time measurement of low-energy-range neutron spectra on board the space shuttle STS-89 (S/MM-8).

    PubMed

    Matsumoto, H; Goka, T; Koga, K; Iwai, S; Uehara, T; Sato, O; Takagi, S

    2001-06-01

    We have developed a real-time, Bonner Ball-type (neutron energy range is from thermal to 15 MeV) neutron spectral measurement system (Bonner Ball Neutron Detector (BBND)) for use on board the International Space Station (ISS). From measurements taken inside STS-89 (S/MM-8), we successfully distinguished neutrons from protons and other particles in a mixed radiation field; a task hitherto considered difficult. Although the experimental period was short, only 3.5 days (January 24-27, 1998), we were able to obtain energy spectral data and the Earth's neutron dose-equivalent map for the ISS orbital conditions (altitude 400 km, orbit inclination angle 51.6 degrees). A method for calculating the neutron energy spectrum and compensating for the particle interaction with the sensors is also described in detail. PMID:11855414

  9. CellNO trap: Novel device for quantitative, real-time, direct measurement of nitric oxide from cultured RAW 267.4 macrophages

    PubMed Central

    He, Weilue; Frost, Megan C.

    2016-01-01

    Nitric oxide (NO), is arguably one of the most important small signaling molecules in biological systems. It regulates various biological responses in both physiological and pathological conditions, often time producing seemingly contradictory results. The details of the effects of NO are highly dependent on the level of NO that cells experience and the temporal aspect of when and how long cells are exposed to NO. Herein, we present a novel measurement system (CellNO trap) that allows real-time NO measurement via chemiluminescence detection from general adhesive cultured cells using standard cell culture media and reagents that does not perturb the cells under investigation. Highly controlled light-initiated NO releasing polymer SNAP-PDMS wa