Science.gov

Sample records for blood gas analyzers

  1. Fiber optic multiple blood gas analyzer

    NASA Astrophysics Data System (ADS)

    Rademaker, Diane M.; Zimmerman, Donald E.; James, Kenneth A.; Quick, William H.

    1994-07-01

    Blood gas analysis has been shown to be the most critical factor in determining patient survivability in a trauma care environment. Present techniques of non-invasive measurement of blood gases in the trauma care unit such as optical pulse oximetry and transcutaneous electrodes are inadequate due to complexity and inaccuracy. The crux of the solution to this problem is the application of a recent, DOD/NASA developed micro-optic spectrophotometer to perform blood gas analysis via fiber optic transmission. The newly developed blood gas analyzer described here will not only overcome the aforementioned drawbacks but also be highly accurate, durable, and safe in hazardous environments: e.g., oxygen rich environments. This spectrophotometer is driven by a microprocessor based `Kalman filter' algorithm which not only controls the monitoring of all the patients in the care center but also separates the patient's superimposed blood gas spectra into its individual components to allow a number of gases critical for trauma care to be analyzed simultaneously.

  2. Blood Analyzer

    NASA Technical Reports Server (NTRS)

    1992-01-01

    In the 1970's, NASA provided funding for development of an automatic blood analyzer for Skylab at the Oak Ridge National Laboratory (ORNL). ORNL devised "dynamic loading," which employed a spinning rotor to load, transfer, and analyze blood samples by centrifugal processing. A refined, commercial version of the system was produced by ABAXIS and is marketed as portable ABAXIS MiniLab MCA. Used in a doctor's office, the equipment can perform 80 to 100 chemical blood tests on a single drop of blood and report results in five minutes. Further development is anticipated.

  3. Are sodium and potassium results on arterial blood gas analyzer equivalent to those on electrolyte analyzer?

    PubMed Central

    Gupta, Shalini; Gupta, Ashwani K.; Singh, Kamaljit; Verma, Minni

    2016-01-01

    Objectives: The present study was conducted with the aim to compare the sodium (Na) and  potassium (K) results on arterial blood gas (ABG) and electrolyte analyzers both of which use direct ion selective electrode technology. Materials and Methods: This was a retrospective study in which data were collected for simultaneous ABG and serum electrolyte samples of a patient received in Biochemistry Laboratory during February to May 2015. The ABG samples received in heparinized syringes were processed on Radiometer ABL80 analyzer immediately. Electrolytes in serum sample were measured on ST-100 Sensa Core analyzer after centrifugation. Data were collected for 112 samples and analyzed with the help of Excel 2010 and  Statistical software for Microsoft excel XLSTAT 2015 software. Results: The mean Na level in serum sample was 139.4 ± 8.2 mmol/L compared to 137.8 ± 10.5 mmol/L in ABG (P < 0.05). The mean difference between the results was 1.6 mmol/L. Mean K level in serum sample was 3.8 ± 0.9 mmol/L as compared to 3.7 ± 0.9 mmol/L in ABG sample (P < 0.05). The mean difference between the results was 0.14 mmol/L. Statistically significant difference was observed in results of two instruments in low Na (<135 mmol/L) and normal K (3.5-5.2 mmol/L) ranges. The 95% limit of agreement for Na and K on both instruments was 9.9 to −13.2 mmol/L and 0.79 to −1.07 mmol/L respectively. Conclusions: The clinicians should be cautious in using the electrolyte results of electrolyte and ABG analyzer in inter exchangeable manner. PMID:27303138

  4. Portable automatic blood analyzer

    NASA Technical Reports Server (NTRS)

    Coleman, R. L.

    1975-01-01

    Analyzer employs chemical-sensing electrodes for determination of blood, gas, and ion concentrations. It is rugged, easily serviced, and comparatively simple to operate. System can analyze up to eight parameters and can be modified to measure other blood constituents including nonionic species, such as urea, glucose, and oxygen.

  5. Gas Analyzer

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The M200 originated in the 1970's under an Ames Research Center/Stanford University contract to develop a small, lightweight gas analyzer for Viking Landers. Although the unit was not used on the spacecraft, it was further developed by The National Institute for Occupational Safety and Health (NIOSH). Three researchers from the project later formed Microsensor Technology, Inc. (MTI) to commercialize the analyzer. The original version (Micromonitor 500) was introduced in 1982, and the M200 in 1988. The M200, a more advanced version, features dual gas chromatograph which separate a gaseous mixture into components and measure concentrations of each gas. It is useful for monitoring gas leaks, chemical spills, etc. Many analyses are completed in less than 30 seconds, and a wide range of mixtures can be analyzed.

  6. Gas Analyzer

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A miniature gas chromatograph, a system which separates a gaseous mixture into its components and measures the concentration of the individual gases, was designed for the Viking Lander. The technology was further developed under National Institute for Occupational Safety and Health (NIOSH) and funded by Ames Research Center/Stanford as a toxic gas leak detection device. Three researchers on the project later formed Microsensor Technology, Inc. to commercialize the product. It is a battery-powered system consisting of a sensing wand connected to a computerized analyzer. Marketed as the Michromonitor 500, it has a wide range of applications.

  7. Portable Gas Analyzer

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The Michromonitor M500 universal gas analyzer contains a series of miniature modules, each of which is a complete gas chromatograph, an instrument which separates a gaseous mixture into its components and measures the concentrations of each gas in the mixture. The system is manufactured by Microsensor Technology, and is used for environmental analysis, monitoring for gas leaks and chemical spills, compliance with pollution laws, etc. The technology is based on a Viking attempt to detect life on Mars. Ames/Stanford miniaturized the system and NIOSH funded further development. Three Stanford researchers commercialized the technology, which can be operated by unskilled personnel.

  8. Residual gas analyzer calibration

    NASA Technical Reports Server (NTRS)

    Lilienkamp, R. H.

    1972-01-01

    A technique which employs known gas mixtures to calibrate the residual gas analyzer (RGA) is described. The mass spectra from the RGA are recorded for each gas mixture. This mass spectra data and the mixture composition data each form a matrix. From the two matrices the calibration matrix may be computed. The matrix mathematics requires the number of calibration gas mixtures be equal to or greater than the number of gases included in the calibration. This technique was evaluated using a mathematical model of an RGA to generate the mass spectra. This model included shot noise errors in the mass spectra. Errors in the gas concentrations were also included in the valuation. The effects of these errors was studied by varying their magnitudes and comparing the resulting calibrations. Several methods of evaluating an actual calibration are presented. The effects of the number of gases in then, the composition of the calibration mixture, and the number of mixtures used are discussed.

  9. Market study: Whole blood analyzer

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A market survey was conducted to develop findings relative to the commercialization potential and key market factors of the whole blood analyzer which is being developed in conjunction with NASA's Space Shuttle Medical System.

  10. CONTINUOUS GAS ANALYZER

    DOEpatents

    Katz, S.; Weber, C.W.

    1960-02-16

    A reagent gas and a sample gas are chemically combined on a continuous basis in a reaction zone maintained at a selected temperature. The reagent gas and the sample gas are introduced to the reaction zone at preselected. constant molar rates of flow. The reagent gas and the selected gas in the sample mixture combine in the reaction zone to form a product gas having a different number of moles from the sum of the moles of the reactants. The difference in the total molar rates of flow into and out of the reaction zone is measured and indicated to determine the concentration of the selected gas.

  11. Regolith Evolved Gas Analyzer

    NASA Technical Reports Server (NTRS)

    Hoffman, John H.; Hedgecock, Jud; Nienaber, Terry; Cooper, Bonnie; Allen, Carlton; Ming, Doug

    2000-01-01

    The Regolith Evolved Gas Analyzer (REGA) is a high-temperature furnace and mass spectrometer instrument for determining the mineralogical composition and reactivity of soil samples. REGA provides key mineralogical and reactivity data that is needed to understand the soil chemistry of an asteroid, which then aids in determining in-situ which materials should be selected for return to earth. REGA is capable of conducting a number of direct soil measurements that are unique to this instrument. These experimental measurements include: (1) Mass spectrum analysis of evolved gases from soil samples as they are heated from ambient temperature to 900 C; and (2) Identification of liberated chemicals, e.g., water, oxygen, sulfur, chlorine, and fluorine. REGA would be placed on the surface of a near earth asteroid. It is an autonomous instrument that is controlled from earth but does the analysis of regolith materials automatically. The REGA instrument consists of four primary components: (1) a flight-proven mass spectrometer, (2) a high-temperature furnace, (3) a soil handling system, and (4) a microcontroller. An external arm containing a scoop or drill gathers regolith samples. A sample is placed in the inlet orifice where the finest-grained particles are sifted into a metering volume and subsequently moved into a crucible. A movable arm then places the crucible in the furnace. The furnace is closed, thereby sealing the inner volume to collect the evolved gases for analysis. Owing to the very low g forces on an asteroid compared to Mars or the moon, the sample must be moved from inlet to crucible by mechanical means rather than by gravity. As the soil sample is heated through a programmed pattern, the gases evolved at each temperature are passed through a transfer tube to the mass spectrometer for analysis and identification. Return data from the instrument will lead to new insights and discoveries including: (1) Identification of the molecular masses of all of the gases

  12. Commercial Hy-Line W-36 pullet and laying hen venous blood gas and chemistry profiles utilizing the portable i-STAT®1 analyzer

    PubMed Central

    Schaal, T. P.; Arango, J.; Wolc, A.; Brady, J. V.; Fulton, J. E.; Rubinoff, I.; Ehr, I. J.; Persia, M. E.; O'Sullivan, N. P.

    2015-01-01

    Venous blood gas and chemistry reference ranges were determined for commercial Hy-Line W-36 pullets and laying hens utilizing the portable i-STAT®1 analyzer and CG8+ cartridges. A total of 632 samples were analyzed from birds between 4 and 110 wk of age. Reference ranges were established for pullets (4 to 15 wk), first cycle laying hens (20 to 68 wk), and second cycle (post molt) laying hens (70 to 110 wk) for the following traits: sodium (Na mmol/L), potassium (K mmol/L), ionized calcium (iCa mmol/L), glucose (Glu mg/dl), hematocrit (Hct% Packed Cell Volume [PCV]), pH, partial pressure carbon dioxide (PCO2 mm Hg), partial pressure oxygen (PO2 mm Hg), total concentration carbon dioxide (TCO2 mmol/L), bicarbonate (HCO3 mmol/L), base excess (BE mmol/L), oxygen saturation (sO2%), and hemoglobin (Hb g/dl). Data were analyzed using ANOVA to investigate the effect of production status as categorized by bird age. Trait relationships were evaluated by linear correlation and their spectral decomposition. All traits differed significantly among pullets and mature laying hens in both first and second lay cycles. Levels for K, iCa, Hct, pH, TCO2, HCO3, BE, sO2, and Hb differed significantly between first cycle and second cycle laying hens. Many venous blood gas and chemistry parameters were significantly correlated. The first 3 eigenvalues explained ∼2/3 of total variation. The first 2 principal components (PC) explained 51% of the total variation and indicated acid-balance and relationship between blood O2 and CO2. The third PC explained 16% of variation and seems to be related to blood iCa. Establishing reference ranges for pullet and laying hen blood gas and chemistry with the i-STAT®1 handheld unit provides a mechanism to further investigate pullet and layer physiology, evaluate metabolic disturbances, and may potentially serve as a means to select breeder candidates with optimal blood gas or chemistry levels on-farm. PMID:26706355

  13. Trace Gas Analyzer (TGA) program

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The design, fabrication, and test of a breadboard trace gas analyzer (TGA) is documented. The TGA is a gas chromatograph/mass spectrometer system. The gas chromatograph subsystem employs a recirculating hydrogen carrier gas. The recirculation feature minimizes the requirement for transport and storage of large volumes of carrier gas during a mission. The silver-palladium hydrogen separator which permits the removal of the carrier gas and its reuse also decreases vacuum requirements for the mass spectrometer since the mass spectrometer vacuum system need handle only the very low sample pressure, not sample plus carrier. System performance was evaluated with a representative group of compounds.

  14. Molecular wake shield gas analyzer

    NASA Technical Reports Server (NTRS)

    Hoffman, J. H.

    1980-01-01

    Techniques for measuring and characterizing the ultrahigh vacuum in the wake of an orbiting spacecraft are studied. A high sensitivity mass spectrometer that contains a double mass analyzer consisting of an open source miniature magnetic sector field neutral gas analyzer and an identical ion analyzer is proposed. These are configured to detect and identify gas and ion species of hydrogen, helium, nitrogen, oxygen, nitric oxide, and carbon dioxide and any other gas or ion species in the 1 to 46 amu mass range. This range covers the normal atmospheric constituents. The sensitivity of the instrument is sufficient to measure ambient gases and ion with a particle density of the order of one per cc. A chemical pump, or getter, is mounted near the entrance aperture of the neutral gas analyzer which integrates the absorption of ambient gases for a selectable period of time for subsequent release and analysis. The sensitivity is realizable for all but rare gases using this technique.

  15. Space Shuttle Trace Gas Analyzer

    NASA Technical Reports Server (NTRS)

    Dencker, W.

    1975-01-01

    A Trace Gas Analyzer (TGA) with the ability to detect the presence of toxic contaminants in the Space Shuttle atmosphere within the subparts-per-million range is under development. The design is a modification of the miniaturized Gas Chromatograph-Mass Spectrometer (GCMS) developed for the Viking Mars Lander. An ambient air sample is injected onto the GC column from a constant volume sample loop and separated into individual compounds for identification by the MS. The GC-MS interface consists of an effluent divider and a silver-paladium separator, an electrochemical cell which removes more than 99.99% of the hydrogen carrier gas. The hydrogen is reclaimed and repressurized without affecting the separator efficiency, a feature which enables a considerable weight reduction in the carrier gas supply system.

  16. Gas dynamics in residual gas analyzer calibration

    SciTech Connect

    Santeler, D.J.

    1987-01-01

    Residual gas analyzers are used for measuring partial flow rates as well as for measuring partial pressures. The required calibration may also be obtained with either known flow rates or known pressures. The calibration and application procedures are straightforward when both are of the same type; however, substantial errors may occur if the two types are mixed. This report develops the basic equations required to convert between partial pressure calibrations and partial flow rate calibrations. It also discusses the question of fractionating and nonfractionating gas flow in various gas inlet and pumping systems.

  17. Multiple-tracer gas analyzer

    SciTech Connect

    Uhl, J.E.

    1982-01-01

    A multi-gas tracer system has been designed, built, and used on an explosively fractured oil shale rubble bed. This paper deals exclusively with the hardware, software, and overall operation of the tracer system. This system is a field portable, self-contained unit, which utilizes a mass spectrometer for gas analysis. The unit has a 20 channel sample port capability and is controlled by a desk top computer. The system is configured to provide a dynamic sensitivity range of up to six orders of magnitude. A roots blower is manifolded to the unit to provide continuous flow in all sample lines. The continuous flow process allows representative samples as well as decreasing the time between each measurement. Typical multiplex cycle time to evaluate four unique gases is approximately 12 seconds.

  18. Gas analyzer for dry/dusty kilns

    SciTech Connect

    Navarre, A.J.

    1986-04-01

    A gas analyzer system is described for use in dry and dusty environments, wherein gas samples are withdrawn by the system from within a chamber. The systems consists of: a plurality of gas analyzer cells, a plurality of sources of calibration gases and a source of purge air, the cells and sources being located outside of the chamber environment; a probe support means including a support pipe extending sufficiently far into the chamber to substantially avoid the effect of tramp air on the measurements, the support pipe having a free end in the chamber; a probe chamber fixed near the free end of the support pipe; an isolation tube means fixed to the probe chamber to bring sample gas into the probe chamber and a filter means within the probe chamber to filter the gas samples; a first pipe means, to selectively pressurize the system, which conducts gas and air from the sources of calibration gas and source of purge air to the probe filter, the first pipe means being laid for a substantial extent of its length within the support pipe; a second pipe means laid for a substantial extent of its length within the support pipe to conduct calibration gases and purge air from the sources to the probe chamber; and a sample tube means laid for a substantial extent of its length within the support pipe to conduct gas samples from the filter to the gas analyzer cells.

  19. LED-based NDIR natural gas analyzer

    NASA Astrophysics Data System (ADS)

    Fanchenko, Sergey; Baranov, Alexander; Savkin, Alexey; Sleptsov, Vladimir

    2016-03-01

    A new generation of the light-emitting diodes (LEDs) and photodiodes (PDs) was used recently to develop an open path non-dispersive infrared (NDIR) methane analyzer. The first open path detector prototype was constructed using LEDs for measurement and reference channels, accordingly, and first measurements for methane gas have been performed using optical paths of the order of several meters [3]. The natural gas consists of several first alkanes, mainly methane, and it is important to have a possibility of measuring all of them. In the present work we report the results of NDIR measurements for propane-butane mixture and new measurements of methane using LEDs for measurement and reference channels at 2300 and 1700 nm wavelengths, accordingly. The necessity of the double beam scheme is demonstrated and obtained results for methane and propane-butane mixture are compared.

  20. 21 CFR 868.1670 - Neon gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Neon gas analyzer. 868.1670 Section 868.1670 Food... DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1670 Neon gas analyzer. (a) Identification. A neon gas analyzer is a device intended to measure the concentration of neon in a gas mixture exhaled by...

  1. 21 CFR 868.1075 - Argon gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Argon gas analyzer. 868.1075 Section 868.1075 Food... DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1075 Argon gas analyzer. (a) Identification. An argon gas analyzer is a device intended to measure the concentration of argon in a gas mixture to aid...

  2. 21 CFR 868.1670 - Neon gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Neon gas analyzer. 868.1670 Section 868.1670 Food... DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1670 Neon gas analyzer. (a) Identification. A neon gas analyzer is a device intended to measure the concentration of neon in a gas mixture exhaled by...

  3. 21 CFR 868.1075 - Argon gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Argon gas analyzer. 868.1075 Section 868.1075 Food... DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1075 Argon gas analyzer. (a) Identification. An argon gas analyzer is a device intended to measure the concentration of argon in a gas mixture to aid...

  4. Studies of deionization and impedance spectroscopy for blood analyzer

    NASA Astrophysics Data System (ADS)

    Kwong, Charlotte C.; Li, Nan; Ho, Chih-Ming

    2005-11-01

    Blood analysis provides vital information for health conditions. For instance, typical infection response is correlated to an elevated White Blood Cell (WBC) count, while low Red Blood Cell (RBC) count, hemoglobin and hematocrit are caused by anemia or internal bleeding. We are developing two essential modules, deionization (DI) chip and microfluidic cytometer with impedance spectroscopy flow, for enabling the realization of a single platform miniaturized blood analyzer. In the proposed analyzer, blood cells are preliminarily sorted by Dielectrophoretic (DEP) means into sub-groups, differentiated and counted by impedance spectroscopy in a flow cytometer. DEP techniques have been demonstrated to stretch DNA, align Carbon Nanotubes (CNT) and trap cells successfully. However, DEP manipulation does not function in biological media with high conductivity. The DI module is designed to account for this challenge. H Filter will serve as an ion extraction platform in a microchamber. Sample and buffer do not mix well in micro scale allowing the ions being extracted by diffusion without increasing the volume. This can keep the downstream processing time short. Micro scale hydrodynamic focusing is employed to place single cell passing along the central plane of the flow cytometer module. By applying an AC electrical field, suspended cells are polarized, membrane capacitance C m, cytoplasm conductivity σ c, and cytoplasm permittivity ɛ c will vary as functions of frequency. Tracing back the monitored current, the numbers of individual cell species can be evaluated.

  5. Point-of-care, portable microfluidic blood analyzer system

    NASA Astrophysics Data System (ADS)

    Maleki, Teimour; Fricke, Todd; Quesenberry, J. T.; Todd, Paul W.; Leary, James F.

    2012-03-01

    Recent advances in MEMS technology have provided an opportunity to develop microfluidic devices with enormous potential for portable, point-of-care, low-cost medical diagnostic tools. Hand-held flow cytometers will soon be used in disease diagnosis and monitoring. Despite much interest in miniaturizing commercially available cytometers, they remain costly, bulky, and require expert operation. In this article, we report progress on the development of a battery-powered handheld blood analyzer that will quickly and automatically process a drop of whole human blood by real-time, on-chip magnetic separation of white blood cells (WBCs), fluorescence analysis of labeled WBC subsets, and counting a reproducible fraction of the red blood cells (RBCs) by light scattering. The whole blood (WB) analyzer is composed of a micro-mixer, a special branching/separation system, an optical detection system, and electronic readout circuitry. A droplet of un-processed blood is mixed with the reagents, i.e. magnetic beads and fluorescent stain in the micro-mixer. Valve-less sorting is achieved by magnetic deflection of magnetic microparticle-labeled WBC. LED excitation in combination with an avalanche photodiode (APD) detection system is used for counting fluorescent WBC subsets using several colors of immune-Qdots, while counting a reproducible fraction of red blood cells (RBC) is performed using a laser light scatting measurement with a photodiode. Optimized branching/channel width is achieved using Comsol Multi-Physics™ simulation. To accommodate full portability, all required power supplies (40v, +/-10V, and +3V) are provided via step-up voltage converters from one battery. A simple onboard lock-in amplifier is used to increase the sensitivity/resolution of the pulse counting circuitry.

  6. Development of an Infrared Fluorescent Gas Analyzer.

    ERIC Educational Resources Information Center

    McClatchie, E. A.

    A prototype model low level carbon monoxide analyzer was developed using fluorescent cell and negative chopping techniques to achieve a device superior to state of art NDIR (Nondispersive infrared) analyzers in stability and cross-sensitivity to other gaseous species. It is clear that this type of analyzer has that capacity. The prototype…

  7. 21 CFR 868.1700 - Nitrous oxide gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Nitrous oxide gas analyzer. 868.1700 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1700 Nitrous oxide gas analyzer. (a) Identification. A nitrous oxide gas analyzer is a device intended to measure the concentration of nitrous...

  8. 21 CFR 868.1500 - Enflurane gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Enflurane gas analyzer. 868.1500 Section 868.1500...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1500 Enflurane gas analyzer. (a) Identification. An enflurane gas analyzer is a device intended to measure the concentration of...

  9. 21 CFR 868.1620 - Halothane gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Halothane gas analyzer. 868.1620 Section 868.1620...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1620 Halothane gas analyzer. (a) Identification. A halothane gas analyzer is a device intended to measure the concentration of...

  10. 21 CFR 868.1620 - Halothane gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Halothane gas analyzer. 868.1620 Section 868.1620...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1620 Halothane gas analyzer. (a) Identification. A halothane gas analyzer is a device intended to measure the concentration of...

  11. 21 CFR 868.1500 - Enflurane gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Enflurane gas analyzer. 868.1500 Section 868.1500...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1500 Enflurane gas analyzer. (a) Identification. An enflurane gas analyzer is a device intended to measure the concentration of...

  12. 21 CFR 868.1700 - Nitrous oxide gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nitrous oxide gas analyzer. 868.1700 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1700 Nitrous oxide gas analyzer. (a) Identification. A nitrous oxide gas analyzer is a device intended to measure the concentration of nitrous...

  13. 21 CFR 868.1640 - Helium gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Helium gas analyzer. 868.1640 Section 868.1640...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1640 Helium gas analyzer. (a) Identification. A helium gas analyzer is a device intended to measure the concentration of helium in a...

  14. 21 CFR 868.1640 - Helium gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Helium gas analyzer. 868.1640 Section 868.1640...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1640 Helium gas analyzer. (a) Identification. A helium gas analyzer is a device intended to measure the concentration of helium in a...

  15. 21 CFR 868.1640 - Helium gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Helium gas analyzer. 868.1640 Section 868.1640...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1640 Helium gas analyzer. (a) Identification. A helium gas analyzer is a device intended to measure the concentration of helium in a...

  16. 21 CFR 868.1640 - Helium gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Helium gas analyzer. 868.1640 Section 868.1640...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1640 Helium gas analyzer. (a) Identification. A helium gas analyzer is a device intended to measure the concentration of helium in a...

  17. 21 CFR 868.1640 - Helium gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Helium gas analyzer. 868.1640 Section 868.1640...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1640 Helium gas analyzer. (a) Identification. A helium gas analyzer is a device intended to measure the concentration of helium in a...

  18. 21 CFR 868.1720 - Oxygen gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Oxygen gas analyzer. 868.1720 Section 868.1720...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1720 Oxygen gas analyzer. (a) Identification. An oxygen gas analyzer is a device intended to measure the concentration of oxygen in...

  19. 21 CFR 868.1720 - Oxygen gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Oxygen gas analyzer. 868.1720 Section 868.1720...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1720 Oxygen gas analyzer. (a) Identification. An oxygen gas analyzer is a device intended to measure the concentration of oxygen in...

  20. 21 CFR 868.1720 - Oxygen gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Oxygen gas analyzer. 868.1720 Section 868.1720...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1720 Oxygen gas analyzer. (a) Identification. An oxygen gas analyzer is a device intended to measure the concentration of oxygen in...

  1. 21 CFR 868.1720 - Oxygen gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Oxygen gas analyzer. 868.1720 Section 868.1720...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1720 Oxygen gas analyzer. (a) Identification. An oxygen gas analyzer is a device intended to measure the concentration of oxygen in...

  2. 21 CFR 868.1720 - Oxygen gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Oxygen gas analyzer. 868.1720 Section 868.1720...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1720 Oxygen gas analyzer. (a) Identification. An oxygen gas analyzer is a device intended to measure the concentration of oxygen in...

  3. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  4. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon...

  5. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon...

  6. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  7. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon...

  8. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  9. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  10. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon...

  11. 21 CFR 868.1400 - Carbon dioxide gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Carbon dioxide gas analyzer. 868.1400 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1400 Carbon dioxide gas analyzer. (a) Identification. A carbon dioxide gas analyzer is a device intended to measure the concentration of carbon...

  12. 21 CFR 868.1430 - Carbon monoxide gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Carbon monoxide gas analyzer. 868.1430 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1430 Carbon monoxide gas analyzer. (a) Identification. A carbon monoxide gas analyzer is a device intended to measure the concentration of...

  13. 21 CFR § 868.1690 - Nitrogen gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2015-04-01

    ... 21 Food and Drugs 8 2015-04-01 2015-04-01 false Nitrogen gas analyzer. § 868.1690 Section § 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1690 Nitrogen gas analyzer. (a) Identification. A nitrogen gas analyzer is a device intended to measure the concentration of nitrogen...

  14. 21 CFR 868.1690 - Nitrogen gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Nitrogen gas analyzer. 868.1690 Section 868.1690...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1690 Nitrogen gas analyzer. (a) Identification. A nitrogen gas analyzer is a device intended to measure the concentration of nitrogen...

  15. 21 CFR 868.1690 - Nitrogen gas analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Nitrogen gas analyzer. 868.1690 Section 868.1690...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1690 Nitrogen gas analyzer. (a) Identification. A nitrogen gas analyzer is a device intended to measure the concentration of nitrogen...

  16. 21 CFR 868.1690 - Nitrogen gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Nitrogen gas analyzer. 868.1690 Section 868.1690...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1690 Nitrogen gas analyzer. (a) Identification. A nitrogen gas analyzer is a device intended to measure the concentration of nitrogen...

  17. 21 CFR 868.1690 - Nitrogen gas analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nitrogen gas analyzer. 868.1690 Section 868.1690...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1690 Nitrogen gas analyzer. (a) Identification. A nitrogen gas analyzer is a device intended to measure the concentration of nitrogen...

  18. 21 CFR 868.1690 - Nitrogen gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Nitrogen gas analyzer. 868.1690 Section 868.1690...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1690 Nitrogen gas analyzer. (a) Identification. A nitrogen gas analyzer is a device intended to measure the concentration of nitrogen...

  19. Performance of a blood chemistry analyzer during parabolic flight

    NASA Technical Reports Server (NTRS)

    Spooner, Brian S.; Claassen, Dale E.; Guikema, James A.

    1990-01-01

    The performance of the Vision System Blood Analyzer during parabolic flight on a KC-135 aircraft (NASA 930) has been tested. This fully automated instrument performed flawlessly in these trials, demonstrating its potential for efficient, reliable use in a microgravity environment. In addition to instrument capability, it is demonstrated that investigators could readily fill specially modified test packs with fluid during zero gravity, and that filled test packs could be easily loaded into VISION during an episode of microgravity.

  20. Expert Assistant For A Clinical Hematology Blood Cell Analyzer

    NASA Astrophysics Data System (ADS)

    Young, Carole; Navlakha, Jainendra K.

    1989-03-01

    The COULTER COUNTER Model S Plus Series instruments are automated clinical hematology blood cell analyzers which measure the count, volume and population distribution of red blood cells, white blood cells and platelets, and hemoglobin from patient blood samples. In the clinical laboratory environment, instrument startup consists of a number of component and system checks to assure proper operation and calibration to insure reliable results are produced on patient samples. If a startup check fails, troubleshooting procedures are provided to assist the operator in determining the cause of the error. Troubleshooting requires expertise in instrument operation, troubleshooting procedures and evaluation of the data produced. This expert system is designed and developed to assist the startup diagnostics of COULTER COUNTER Model S Plus Series instruments. The system reads data produced by the instrument and validates it against expected values. If the values are not all correct, then the troubleshooting starts. Troubleshooting is handled for the most common subsystem problems and those which the operator has the equipment and knowledge to handle, problems that are cheapest to fix and problems that are quickest to fix. The expert system restarts the startup sequence whenever troubleshooting has been successful or recommends calling Customer Service when unsuccessful.

  1. 46 CFR 148.420 - Flammable gas analyzers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Flammable gas analyzers. 148.420 Section 148.420... MATERIALS THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.420 Flammable gas analyzers..., each vessel transporting the material, other than an unmanned barge, must have on board a gas...

  2. 46 CFR 148.415 - Toxic gas analyzers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Toxic gas analyzers. 148.415 Section 148.415 Shipping... MATERIALS THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.415 Toxic gas analyzers. When... vessel transporting the material, other than an unmanned barge, must have on board a gas...

  3. 46 CFR 148.415 - Toxic gas analyzers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Toxic gas analyzers. 148.415 Section 148.415 Shipping... MATERIALS THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.415 Toxic gas analyzers. When... vessel transporting the material, other than an unmanned barge, must have on board a gas...

  4. 46 CFR 148.420 - Flammable gas analyzers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Flammable gas analyzers. 148.420 Section 148.420... MATERIALS THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.420 Flammable gas analyzers..., each vessel transporting the material, other than an unmanned barge, must have on board a gas...

  5. 46 CFR 148.415 - Toxic gas analyzers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Toxic gas analyzers. 148.415 Section 148.415 Shipping... MATERIALS THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.415 Toxic gas analyzers. When... vessel transporting the material, other than an unmanned barge, must have on board a gas...

  6. 46 CFR 148.420 - Flammable gas analyzers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Flammable gas analyzers. 148.420 Section 148.420... MATERIALS THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.420 Flammable gas analyzers..., each vessel transporting the material, other than an unmanned barge, must have on board a gas...

  7. 46 CFR 148.415 - Toxic gas analyzers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Toxic gas analyzers. 148.415 Section 148.415 Shipping... MATERIALS THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.415 Toxic gas analyzers. When... vessel transporting the material, other than an unmanned barge, must have on board a gas...

  8. The use of mass spectrometry to analyze dried blood spots.

    PubMed

    Wagner, Michel; Tonoli, David; Varesio, Emmanuel; Hopfgartner, Gérard

    2016-01-01

    Dried blood spots (DBS) typically consist in the deposition of small volumes of capillary blood onto dedicated paper cards. Comparatively to whole blood or plasma samples, their benefits rely in the fact that sample collection is easier and that logistic aspects related to sample storage and shipment can be relatively limited, respectively, without the need of a refrigerator or dry ice. Originally, this approach has been developed in the sixties to support the analysis of phenylalanine for the detection of phenylketonuria in newborns using bacterial inhibition test. In the nineties tandem mass spectrometry was established as the detection technique for phenylalanine and tyrosine. DBS became rapidly recognized for their clinical value: they were widely implemented in pediatric settings with mass spectrometric detection, and were closely associated to the debut of newborn screening (NBS) programs, as a part of public health policies. Since then, sample collection on paper cards has been explored with various analytical techniques in other areas more or less successfully regarding large-scale applications. Moreover, in the last 5 years a regain of interest for DBS was observed and originated from the bioanalytical community to support drug development (e.g., PK studies) or therapeutic drug monitoring mainly. Those recent applications were essentially driven by improved sensitivity of triple quadrupole mass spectrometers. This review presents an overall view of all instrumental and methodological developments for DBS analysis with mass spectrometric detection, with and without separation techniques. A general introduction to DBS will describe their advantages and historical aspects of their emergence. A second section will focus on blood collection, with a strong emphasis on specific parameters that can impact quantitative analysis, including chromatographic effects, hematocrit effects, blood effects, and analyte stability. A third part of the review is dedicated to

  9. 21 CFR 868.1670 - Neon gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Neon gas analyzer. 868.1670 Section 868.1670 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1670 Neon gas analyzer. (a) Identification. A...

  10. 21 CFR 868.1620 - Halothane gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Halothane gas analyzer. 868.1620 Section 868.1620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1620 Halothane gas analyzer....

  11. 21 CFR 868.1075 - Argon gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Argon gas analyzer. 868.1075 Section 868.1075 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1075 Argon gas analyzer. (a) Identification....

  12. 21 CFR 868.1670 - Neon gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Neon gas analyzer. 868.1670 Section 868.1670 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1670 Neon gas analyzer. (a) Identification. A...

  13. 21 CFR 868.1500 - Enflurane gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Enflurane gas analyzer. 868.1500 Section 868.1500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1500 Enflurane gas analyzer....

  14. 21 CFR 868.1700 - Nitrous oxide gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Nitrous oxide gas analyzer. 868.1700 Section 868.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1700 Nitrous oxide gas analyzer....

  15. 21 CFR 868.1075 - Argon gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Argon gas analyzer. 868.1075 Section 868.1075 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1075 Argon gas analyzer. (a) Identification....

  16. 21 CFR 868.1620 - Halothane gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Halothane gas analyzer. 868.1620 Section 868.1620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1620 Halothane gas analyzer....

  17. 21 CFR 868.1670 - Neon gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Neon gas analyzer. 868.1670 Section 868.1670 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1670 Neon gas analyzer. (a) Identification. A...

  18. 21 CFR 868.1500 - Enflurane gas analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Enflurane gas analyzer. 868.1500 Section 868.1500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1500 Enflurane gas analyzer....

  19. 21 CFR 868.1700 - Nitrous oxide gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Nitrous oxide gas analyzer. 868.1700 Section 868.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1700 Nitrous oxide gas analyzer....

  20. 21 CFR 868.1620 - Halothane gas analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Halothane gas analyzer. 868.1620 Section 868.1620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1620 Halothane gas analyzer....

  1. 21 CFR 868.1500 - Enflurane gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Enflurane gas analyzer. 868.1500 Section 868.1500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1500 Enflurane gas analyzer....

  2. 21 CFR 868.1075 - Argon gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Argon gas analyzer. 868.1075 Section 868.1075 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1075 Argon gas analyzer. (a) Identification....

  3. 21 CFR 868.1700 - Nitrous oxide gas analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Nitrous oxide gas analyzer. 868.1700 Section 868.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1700 Nitrous oxide gas analyzer....

  4. Sensor gas analyzer for acetone determination in expired air

    NASA Astrophysics Data System (ADS)

    Baranov, Vitaly V.

    2001-05-01

    Diseases and changes in the way of life change the concentration and composition of the expired air. Our adaptable gas analyzer is intended for the selective analysis of expired air and can be adapted for the solution of current diagnostic and analytical tasks by the user (a physician or a patient). Having analyzed the existing trends in the development of noninvasive diagnostics we have chosen the method of noninvasive acetone detection in expired air, where the acetone concentration correlates with blood and urine glucose concentrations. The appearance of acetone in expired air is indicative of disorders that may be caused not only by diabetes but also be wrong diet, incorrect sportsmen training etc. To control the disorders one should know the acetone concentration in the human body. This knowledge allows one to judge upon the state of the patient, choose a correct diet that will not cause damage to the patient's health, determine sportsmen training efficiency and results and solve the artificial pancreas problem. Our device provide highly accurate analysis, rapid diagnostics and authentic acetone quantification in the patient's body at any time aimed at prediction of the patient's state and assessing the efficiency of the therapy used. Clinical implementation of the device will improve the health and save lives of many thousands of diabetes sufferers.

  5. Colorimetric blood-gas monitoring sensors

    NASA Astrophysics Data System (ADS)

    Proctor, Keith J.; Seifert, George P.

    1993-05-01

    Colorimetric fiber optic sensors have been developed for measuring the pH and pCO2 of blood. These sensors are fabricated using a single 125 micrometers diameter optical fiber. Located at the distal end of the fiber is a capsule that contains a pH sensitive dye. The pCO2 sensor is fabricated from a pH sensor with the addition of a salt, bicarbonate, and the encapsulation with an ion impermeable gas permeable membrane. The distal end of the capsule is terminated with a reflective surface. The reflective surface can either be a polished metallic surface or, in this case, a TiO2 impregnated epoxy. The disposable sensor mates with an optical connector that contains two optical fibers of the same size as the disposable sensor. The two fibers within the optical cable provide a light path for both the antegrade and retrograde optical signals. These fibers are terminated at either the LED source or the detector. A prototype sensor assembly that incorporates the measurement of three physiological parameters (pH, pCO2, and sO2) has been demonstrated to fit within a standard 20 gauge arterial catheter, typically used for radial artery blood pressure monitoring, without significant damping of the blood pressure waveform. The pH sensor has a range of 6.9 - 7.8 with a precision of 0.01 pH units and the pCO2 sensor has a range of 15 - 95 mm Hg with a precision of 3 mm Hg. The long term drift pH drift is less than 0.01 pH unit per 8 hours and the pCO2 drift is less than 1 mm Hg per 8 hours. Sensor performance in the canine has demonstrated that the pH sensor is accurate to within +/- 0.03 pH units and the pCO2 sensor is accurate to within +/- 3 mm Hg when compared to a typical blood gas analyzer.

  6. The invention and development of blood gas analysis apparatus.

    PubMed

    Severinghaus, John W

    2002-07-01

    In 1953, the doctor draft interrupted Dr. Severinghaus' anesthesia and physiology training and sent him to the National Institutes of Health as director of anesthesia research at the newly opened Clinical Center. He developed precise laboratory partial pressure of carbon dioxide (PCO(2)) and pH analysis to investigate lung blood gas exchange during hypothermia. Constants for carbon dioxide solubility and pK' were more accurately determined. In August 1954, he heard Richard Stow describe invention of a carbon dioxide electrode and immediately built one, improved its stability, and tested its response characteristics. In April 1956, he also heard Leland Clark reveal his invention of an oxygen electrode. Dr. Severinghaus obtained one and constructed a stirred cuvette in which blood partial pressure of oxygen (PO(2)) could be accurately measured. Technician Bradley and Dr. Severinghaus combined these, making the first blood gas analysis system in 1957 and 1958, and shortly thereafter, they added a pH electrode. Blood gas analyzers rapidly developed commercially. Dr. Severinghaus collaborated with Astrup and other Danes on the Haldane and Bohr effects and their concepts of base excess during two sabbaticals in Copenhagen. Work with both Astrup and Roughton on the oxygen dissociation curve led Dr. Severinghaus to devise a modified Hill equation that closely fit their new, better human oxygen dissociation curve and a blood gas slide rule that solved oxygen dissociation curve, PCO(2), pH, and acid-base questions. Blood gas analysis revolutionized both clinical medicine and cardiorespiratory and metabolic physiology. PMID:12131126

  7. Early Blood Gas Abnormalities and the Preterm Brain

    PubMed Central

    Leviton, Alan; Allred, Elizabeth; Kuban, Karl C. K.; Dammann, Olaf; O'Shea, T. Michael; Hirtz, Deborah; Schreiber, Michael D.; Paneth, Nigel

    2010-01-01

    The authors explored associations between blood gas abnormalities in more than 1,000 preterm infants during the first postnatal days and indicators of neonatal brain damage. During 2002–2004, women delivering infants before 28 weeks’ gestation at one of 14 participating institutions in 5 US states were asked to enroll in the study. The authors compared infants with blood gas values in the highest or lowest quintile for gestational age and postnatal day (extreme value) on at least 1 of the first 3 postnatal days with the remainder of the subjects, with separate analyses for blood gas abnormalities on multiple days and for partial pressure of oxygen in the alveolar gas of <35. Outcomes analyzed were ventriculomegaly and an echolucent lesion on an ultrasound scan in the neonatal intensive care unit, and cerebral palsy, microcephaly, and a low score on a Bayley Scale of Infant Development at 24 months. Every blood gas derangement (hypoxemia, hyperoxemia, hypocapnia, hypercapnia, and acidosis) was associated with multiple indicators of brain damage. However, for some, the associations were seen with only 1 day of exposure; others were evident with 2 or more days’ exposure. Findings suggest that individual blood gas derangements do not increase brain damage risk. Rather, the multiple derangements associated with indicators of brain damage might be indicators of immaturity/vulnerability and illness severity. PMID:20807736

  8. 20 CFR 718.105 - Arterial blood-gas studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Arterial blood-gas studies. 718.105 Section... blood-gas studies. (a) Blood-gas studies are performed to detect an impairment in the process of... either at rest or during exercise. No blood-gas study shall be performed if medically contraindicated....

  9. Raman gas analyzer applicability to monitoring of gaseous air pollution

    NASA Astrophysics Data System (ADS)

    Petrov, D. V.; Matrosov, I. I.; Tikhomirov, A. A.

    2015-11-01

    It is shown that the main problem, arising when designing a stationary Raman gas analyzer intended to monitor gaseous air pollutions, is to get SRS signals of sufficient intensity. The engineering solutions are presented that provide the required sensitivity (~ 50-100 ppb). It is achieved by compressing a gas medium under analysis and gaining intensity of the exciting laser radiation.

  10. 40 CFR 1065.309 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.309 Continuous... ambient air drawn into the probe. Select span gases for the species being continuously combined, other... air. You may use a multi-gas span gas, such as NO-CO-CO2-C3H8-CH4, to verify multiple analyzers at...

  11. 40 CFR 1065.309 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.309 Continuous... ambient air drawn into the probe. Select span gases for the species being continuously combined, other... air. You may use a multi-gas span gas, such as NO-CO-CO2-C3H8-CH4, to verify multiple analyzers at...

  12. 40 CFR 1065.309 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.309 Continuous... ambient air drawn into the probe. Select span gases for the species being continuously combined, other... air. You may use a multi-gas span gas, such as NO-CO-CO2-C3H8-CH4, to verify multiple analyzers at...

  13. 40 CFR 1065.309 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.309 Continuous... ambient air drawn into the probe. Select span gases for the species being continuously combined, other... air. You may use a multi-gas span gas, such as NO-CO-CO2-C3H8-CH4, to verify multiple analyzers at...

  14. Multicomponent gas analyzers based on tunable diode lasers

    SciTech Connect

    Stepanov, E.V.; Zyrianov, P.V.; Khusnutdinov, A.N.; Kouznetsov, A.I.; Ponurovskii, Y.Ya.

    1996-12-31

    A family of multicomponent gas analyzers based on tunable diode lasers (TDL) are presented including: an open optical path 3-component gas analyzer for monitoring atmosphere pollution; a 4-gas component analyzer with a multipass cell, a multichannel TDL system with multipass cell and MIR fiber optics delivery, and a multichannel TDL analyzer for breath content gas analysis. A4B6 tunable diode lasers of different spectral region from 4 to 12 micron were used in every channel of the analyzers to obtain atmospheric transmission spectra and to measure concentration of studied gases. Main gaseous atmospheric pollutants like CO, NO, NH{sub 3}, CH{sub 4}, SO{sub 2}, etc. and some of breath gases could be measured at ppb concentration level in real time with these systems depending on customers requirements. The analyzers are driven by IBM compatible PC. The first results on field monitoring tests as well as on their application to human exhalation content analysis and human exposure monitoring are presented.

  15. A novel CO 2 gas analyzer based on IR absorption

    NASA Astrophysics Data System (ADS)

    Zhang, Guangjun; Wu, Xiaoli

    2004-08-01

    Carbon dioxide (CO 2) gas analyzer can be widely used in many fields. A novel CO 2 gas analyzer based on infrared ray (IR) absorption is presented sufficiently in this paper. Applying Lambert-Beer Law, a novel space-double-beam optical structure is established successfully. The optical structure includes an IR source, a gas cell, a bandpass filter with a transmission wavelength at 4.26 μm, another bandpass filter with a transmission wavelength at 3.9 μm, and two IR detectors. Based on Redial Basic Function (RBF) artificial neural network, the measuring model of IR CO 2 analyzer is established with a high accuracy. A dynamic compensation filter is effectively designed to improve the dynamic characteristic of the IR CO 2 analyzer without gas pump. The IR CO 2 analyzer possesses the advantages of high accuracy and mechanical reliability with small volume, lightweight, and low-power consumption. Therefore, it can be used in such relevant fields as environmental protection, processing control, chemical analysis, medical diagnosis, and space environmental and control systems.

  16. Continuous blood gas monitoring in femoral arteries

    NASA Astrophysics Data System (ADS)

    Schlain, Les A.; Spar, Steven M.; Dellinger, Bart

    1995-05-01

    Continuous intra-arterial blood gas monitoring is a potentially valuable tool in the surgical and intensive care arenas. Patient oxygenation and acid base status can change rapidly and without warning. The ability to monitor pHa, PaCO2 and PaO2 in arterial blood will be a major medical advance for the anesthesiologist and intensivist. Intra-arterial blood gas sensors are typically placed in radial arteries. In certain patient populations accurate monitoring is not possible in radial arteries due to arterial environmental factors such as hypotension, vasoconstriction and atherosclerotic disease. These same factors can make radial cannulation difficult resulting in traumatic catheter insertion, thereby further compromising flow conditions. In situations where radial artery flow is expected to be compromised, selecting a large vessel for sensor placement is desirable. We report an initial feasibility study of our blood gas monitoring system using the femoral artery as the sensing site. Clinical results are presented as well as potential advantages and disadvantages associated with monitoring in the femoral artery.

  17. Field emitter based extractor gauges and residual gas analyzers

    SciTech Connect

    Changkun Dong; G. Rao Myneni

    1999-04-01

    Attempts at using the Spindt-type molybdenum field emitter arrays in the extractor gauges and a residual gas analyzer are presented in this article. The sensitivity of the fuel emitter gauge is as high as 11 Torr{sup -1}. The departure from linearity of the pressure versus ion current measurements did not exceed 10% over the pressure range of 10{sup -10} - 10{sup -6} Torr. Stable sensitivities for nitrogen, helium, and hydrogen were achieved below 10{sup -7} Torr with the field emitter residual gas analyzer. The slightly reduced emission current and sensitivity, after long-term operation, are of concern and need to be addressed. Residual gas spectra indicate that when using field emitters, the electron stimulated desorption ions (O{sup +}, F{sup +}, and Cl{sup +}) are reduced as compared to those made using a hot filament source.

  18. 21 CFR 868.1200 - Indwelling blood oxygen partial pressure (PO2) analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Indwelling blood oxygen partial pressure (PO2... Indwelling blood oxygen partial pressure (PO2) analyzer. (a) Identification. An indwelling blood oxygen... electrode) and that is used to measure, in vivo, the partial pressure of oxygen in blood to aid...

  19. 21 CFR 868.1200 - Indwelling blood oxygen partial pressure (PO2) analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Indwelling blood oxygen partial pressure (PO2... Indwelling blood oxygen partial pressure (PO2) analyzer. (a) Identification. An indwelling blood oxygen... electrode) and that is used to measure, in vivo, the partial pressure of oxygen in blood to aid...

  20. 21 CFR 868.1200 - Indwelling blood oxygen partial pressure (PO2) analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Indwelling blood oxygen partial pressure (PO2... Indwelling blood oxygen partial pressure (PO2) analyzer. (a) Identification. An indwelling blood oxygen... electrode) and that is used to measure, in vivo, the partial pressure of oxygen in blood to aid...

  1. 21 CFR 868.1200 - Indwelling blood oxygen partial pressure (PO2) analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Indwelling blood oxygen partial pressure (PO2... Indwelling blood oxygen partial pressure (PO2) analyzer. (a) Identification. An indwelling blood oxygen... electrode) and that is used to measure, in vivo, the partial pressure of oxygen in blood to aid...

  2. 21 CFR 868.1200 - Indwelling blood oxygen partial pressure (PO2) analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Indwelling blood oxygen partial pressure (PO2... Indwelling blood oxygen partial pressure (PO2) analyzer. (a) Identification. An indwelling blood oxygen... electrode) and that is used to measure, in vivo, the partial pressure of oxygen in blood to aid...

  3. 21 CFR 868.1170 - Indwelling blood hydrogen ion concentration (pH) analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Indwelling blood hydrogen ion concentration (pH... Indwelling blood hydrogen ion concentration (pH) analyzer. (a) Identification. An indwelling blood hydrogen ion concentration (pH) analyzer is a device that consists of a catheter-tip pH electrode and that...

  4. 21 CFR 868.1170 - Indwelling blood hydrogen ion concentration (pH) analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Indwelling blood hydrogen ion concentration (pH... Indwelling blood hydrogen ion concentration (pH) analyzer. (a) Identification. An indwelling blood hydrogen ion concentration (pH) analyzer is a device that consists of a catheter-tip pH electrode and that...

  5. 21 CFR 868.1170 - Indwelling blood hydrogen ion concentration (pH) analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Indwelling blood hydrogen ion concentration (pH... Indwelling blood hydrogen ion concentration (pH) analyzer. (a) Identification. An indwelling blood hydrogen ion concentration (pH) analyzer is a device that consists of a catheter-tip pH electrode and that...

  6. 21 CFR 868.1170 - Indwelling blood hydrogen ion concentration (pH) analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Indwelling blood hydrogen ion concentration (pH... Indwelling blood hydrogen ion concentration (pH) analyzer. (a) Identification. An indwelling blood hydrogen ion concentration (pH) analyzer is a device that consists of a catheter-tip pH electrode and that...

  7. 21 CFR 868.1170 - Indwelling blood hydrogen ion concentration (pH) analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Indwelling blood hydrogen ion concentration (pH... Indwelling blood hydrogen ion concentration (pH) analyzer. (a) Identification. An indwelling blood hydrogen ion concentration (pH) analyzer is a device that consists of a catheter-tip pH electrode and that...

  8. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a...

  9. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a...

  10. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a...

  11. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a...

  12. 21 CFR 868.1150 - Indwelling blood carbon dioxide partial pressure (PCO2) analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Indwelling blood carbon dioxide partial pressure....1150 Indwelling blood carbon dioxide partial pressure (PCO2) analyzer. (a) Identification. An indwelling blood carbon dioxide partial pressure PCO2 analyzer is a device that consists of a...

  13. 21 CFR 868.1120 - Indwelling blood oxyhemoglobin concentration analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... concentration analyzer is a photoelectric device used to measure, in vivo, the oxygen-carrying capacity of... approved PMA or declared completed PDP in effect before being placed in commercial distribution....

  14. 21 CFR 868.1120 - Indwelling blood oxyhemoglobin concentration analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... concentration analyzer is a photoelectric device used to measure, in vivo, the oxygen-carrying capacity of... approved PMA or declared completed PDP in effect before being placed in commercial distribution....

  15. 21 CFR 868.1120 - Indwelling blood oxyhemoglobin concentration analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... concentration analyzer is a photoelectric device used to measure, in vivo, the oxygen-carrying capacity of... approved PMA or declared completed PDP in effect before being placed in commercial distribution....

  16. 20 CFR 718.105 - Arterial blood-gas studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Arterial blood-gas studies. 718.105 Section... DEATH DUE TO PNEUMOCONIOSIS Criteria for the Development of Medical Evidence § 718.105 Arterial blood-gas studies. (a) Blood-gas studies are performed to detect an impairment in the process of...

  17. Characteristics and performance of several mass spectrometer residual gas analyzers

    NASA Technical Reports Server (NTRS)

    Hultzman, W. W.

    1974-01-01

    The operation and properties of various mass-spectrometer residual gas analyzers for use in vacuum measurements were analyzed in terms of efficiencies of ion extraction, ion separation and transmission, and ion collection. Types of instruments studied were magnetic sector, omegatron, quadrupole, and monopole. Experimental results presented include absolute sensitivity to argon, relative sensitivity to 10 gases, and cracking patterns for these gases. It is shown that the properties are strongly dependent on instrument range, resolution, and the particular voltages, currents, or field intensities used to control the instrument.

  18. Polarized 3He Gas Circulating Technologies for Neutron Analyzers

    SciTech Connect

    Watt, David; Hersman, Bill

    2014-12-10

    We describe the development of an integrated system for quasi-continuous operation of a large volume neutron analyzer. The system consists of a non-magnetic diaphragm compressor, a prototype large volume helium polarizer, a surrogate neutron analyzer, a non-depolarizing gas storage reservoir, a non-ferrous valve manifold for handling gas distribution, a custom rubidium-vapor gas return purifier, and wire-wound transfer lines, all of which are immersed in a two-meter external magnetic field. Over the Phase II period we focused on three major tasks required for the successful deployment of these types of systems: 1) design and implementation of gas handling hardware, 2) automation for long-term operation, and 3) improvements in polarizer performance, specifically fabrication of aluminosilicate optical pumping cells. In this report we describe the design, implementation, and testing of the gas handling hardware. We describe improved polarizer performance resulting from improved cell materials and fabrication methods. These improvements yielded valved 8.5 liter cells with relaxation times greater than 12 hours. Pumping this cell with 1500W laser power with 1.25nm linewidth yielded peak polarizations of 60%, measured both inside and outside the polarizer. Fully narrowing this laser to 0.25nm, demonstrated separately on one stack of the four, would have allowed 70% polarization with this cell. We demonstrated the removal of 5 liters of polarized helium from the polarizer with no measured loss of polarization. We circulated the gas through a titanium-clad compressor with polarization loss below 3% per pass. We also prepared for the next phase of development by refining the design of the polarizer so that it can be engineer-certified for pressurized operation. The performance of our system far exceeds comparable efforts elsewhere.

  19. Gas Reactor Plant Analyzer and Simulator for Hydrogen Production

    Energy Science and Technology Software Center (ESTSC)

    2004-01-01

    This software is used to study and analyze various configurations of plant equipment for gas cooled nuclear reactor applications. The user of this software would likely be interested in optimizing the economic, safety, and operating performance of this type of reactor. The code provides the capability for the user through his input to configure networks of nuclear reactor components. The components available include turbine, compressor, heat exchanger, reactor core, coolers, bypass valves, and control systems.

  20. Stack gas analyzer and thermal oxidation device therefor

    SciTech Connect

    Vincent, A.

    1980-07-08

    A stack gas analyzer is described for connection from a recovery stack, said stack gas analyzer comprising: first means including a first outlet for producing a flow of a dehydrated mixture of the gases flowing in said recovery stck, said dehydrated mixture including sulfur dioxide, total reduced sulfur (TRS), and oxygen remaining after combustion utilizing an oxygen rate a few percent in excess of the stoichiometric rate; a scrubber having an inlet and an outlet to receive said dehydrated mixture, said scrubber having a composition to remove sulfur dioxide from said dehydrated mixture without removing the said TRS, said scrubber outlet having a flow therethrough of a trs sample mixture the same as said dehydrated mixture except for the removal of sulfur dioxide therefrom and including at least some of said oxygen; a coulometric titrator having a cell including an inlet and an outlet, and having second means to produce an electrical output signal proportional to the concentration of sulfur dioxide in an oxidized gas mixture passing through said cell from said cell inlet to said cell outlet; a conduit connected from said scrubber outlet to said cell inlet, saidaconduit having a flow of said TRS sample therein; and third means to heat said TRS sample in said conduit to a pedetermined temperature such that said trs is oxidized to sulfur dioxide.

  1. Graphic Three-Axes Presentation of Residual Gas Analyzer Data

    NASA Technical Reports Server (NTRS)

    Johnson, Kenneth R.; Levi, Alejandro G.

    1997-01-01

    Residual gas analyzers (RGA) are commonly used to measure the composition of residual gases in thermal-vacuum test chambers. Measurements from RGA's are often used to identify and quantify outgassing contaminants from a test article during thermal-vacuum testing. RGA data is typically displayed as snapshots in time, showing instantaneous concentrations of ions from ionized residual gas molecules at different atomic masses. This ion concentration information can be interpreted to be representative of the composition of the residual gas in the chamber at the instant of analysis. Typically, test personnel are most interested in tracking the time history of changes in the composition of chamber residual gas to determine the relative cleanliness and the clean-up rate of the test article under vacuum. However, displays of instantaneous RGA data cannot provide test personnel with the preferred time history information. In order to gain an understanding of gas composition trends, a series of plots of individual data snapshots must be analyzed. This analysis is cumbersome and still does not provide a very satisfactory view of residual gas composition trends. A method was devised by the authors to present RCA data in a three-axis format, plotting Atomic Mass Unit (AMU), the Ionization Signal Response (ISR) as amps/torr as a function of AMU, and Time, to provide a clear graphic visualization of trends of changes in ISR with respect to time and AMU (representative of residual gas composition). This graphic visualization method provides a valuable analytical tool to interpret test article outgassing rates during thermal vacuum tests. Raw RGA data was extracted from a series of delimited ASCII files and then converted to a data array in a spreadsheet. Consequently, using the 3-D plotting functionality provided by the spreadsheet program, 3-D plots were produced. After devising the data format conversion process, the authors began developing a program to provide real-time 3-D

  2. Description of the prototype diagnostic residual gas analyzer for ITER.

    PubMed

    Younkin, T R; Biewer, T M; Klepper, C C; Marcus, C

    2014-11-01

    The diagnostic residual gas analyzer (DRGA) system to be used during ITER tokamak operation is being designed at Oak Ridge National Laboratory to measure fuel ratios (deuterium and tritium), fusion ash (helium), and impurities in the plasma. The eventual purpose of this instrument is for machine protection, basic control, and physics on ITER. Prototyping is ongoing to optimize the hardware setup and measurement capabilities. The DRGA prototype is comprised of a vacuum system and measurement technologies that will overlap to meet ITER measurement requirements. Three technologies included in this diagnostic are a quadrupole mass spectrometer, an ion trap mass spectrometer, and an optical penning gauge that are designed to document relative and absolute gas concentrations. PMID:25430381

  3. Description of the prototype diagnostic residual gas analyzer for ITERa)

    NASA Astrophysics Data System (ADS)

    Younkin, T. R.; Biewer, T. M.; Klepper, C. C.; Marcus, C.

    2014-11-01

    The diagnostic residual gas analyzer (DRGA) system to be used during ITER tokamak operation is being designed at Oak Ridge National Laboratory to measure fuel ratios (deuterium and tritium), fusion ash (helium), and impurities in the plasma. The eventual purpose of this instrument is for machine protection, basic control, and physics on ITER. Prototyping is ongoing to optimize the hardware setup and measurement capabilities. The DRGA prototype is comprised of a vacuum system and measurement technologies that will overlap to meet ITER measurement requirements. Three technologies included in this diagnostic are a quadrupole mass spectrometer, an ion trap mass spectrometer, and an optical penning gauge that are designed to document relative and absolute gas concentrations.

  4. Description of the prototype diagnostic residual gas analyzer for ITER

    SciTech Connect

    Younkin, T. R.; Biewer, T. M.; Klepper, C. C.; Marcus, C.

    2014-11-15

    The diagnostic residual gas analyzer (DRGA) system to be used during ITER tokamak operation is being designed at Oak Ridge National Laboratory to measure fuel ratios (deuterium and tritium), fusion ash (helium), and impurities in the plasma. The eventual purpose of this instrument is for machine protection, basic control, and physics on ITER. Prototyping is ongoing to optimize the hardware setup and measurement capabilities. The DRGA prototype is comprised of a vacuum system and measurement technologies that will overlap to meet ITER measurement requirements. Three technologies included in this diagnostic are a quadrupole mass spectrometer, an ion trap mass spectrometer, and an optical penning gauge that are designed to document relative and absolute gas concentrations.

  5. Intercomparison of gas analyzers for methane flux measurements

    NASA Astrophysics Data System (ADS)

    Haapanala, S.; Rinne, J.; Vesala, T.

    2010-12-01

    Four gas analyzers, capable of measuring methane concentration at a response time necessary for eddy covariance flux measurements, were operated in parallel for about six months between March and August 2010. Their reliability, need of maintenance, user friendliness, data coverage, and data quality were evaluated. The primary aim of this campaign was to provide an instrumentation suggestion for the European Research Infrastructure ICOS (Integrated Carbon Observation System). The instruments used were TGA100A (Campbell Scientific Inc.), RMT-200 (Los Gatos Research Inc.) , G1301-f (Picarro Inc.), and LI-7700 (Li-Cor Inc.). The last one, LI-7700, was a prototype of a later commercialized open path analyzer. The other instruments were closed path analyzers. The measurement site is an oligotrophic open fen Siikaneva, located in southern Finland. The site provides spatially quite uniform methane flux within the footprint. The methane flux rises in the spring, peaks in early August and falls down during the autumn. This provides excellent opportunity to study the performance of the analyzers at different CH4 flux levels from near zero up to about 5 mg m-2 h-1. The preliminary results show great similarity among the instruments in both concentrations and fluxes. Detailed numbers of the measurement characteristics will be provided later. The reliability and need of maintenance are difficult to evaluate quantitatively during that short period.

  6. User's guide to the Residual Gas Analyzer (RGA)

    SciTech Connect

    Artman, S.A.

    1988-08-04

    The Residual Gas Analyzer (RGA), a Model 100C UTI quadrupole mass spectrometer, measures the concentrations of selected masses in the Fusion Energy Division's (FED) Advanced Toroidal Facility (ATF). The RGA software is a VAX FORTRAN computer program which controls the experimental apparatus, records the raw data, performs data reduction, and plots the data. The RGA program allows data to be collected from an RGA on ATF or from either of two RGAs in the laboratory. In the laboratory, the RGA diagnostic plays an important role in outgassing studied on various candidate materials for fusion experiments. One such material, graphite, is being used more often in fusion experiments due to its ability to withstand high power loads. One of the functions of the RGA diagnostic is aid in the determination of the best grade of graphite to be used in these experiments and to study the procedures used to condition it. A procedure of particular interest involves baking the graphite sample in order to remove impurities that may be present in it. These impurities can be studied while in the ATF plasma or while being baked and outgassed in the laboratory. The Residual Gas Analyzer is a quadrupole mass spectrometer capable of scanning masses ranging in size from 1 atomic mass unit (amu) to 300 amu while under computer control. The procedure for collecting data for a particular mass is outlined.

  7. Blood gas analysis and cooximetry in retired racing Greyhounds

    PubMed Central

    Zaldivar-Lopez, Sara; Chisnell, Hope K.; Guillermo Couto, C.; Westendorf-Stingle, Nicole; Marin, Liliana M.; Iazbik, Maria C.; Cooper, Edward S.; Wellman, Maxey L.; Muir, William W.

    2013-01-01

    Objective The purposes of this study were to evaluate the oxygen affinity of hemoglobin (Hb) in healthy retired racing Greyhounds via cooximetry, and to establish reference intervals for blood gases and cooximetry in this breed. Design Prospective clinical study. Setting University Teaching Hospital. Animals Fifty-seven Greyhounds and 30 non-Greyhound dogs. Interventions Venous blood samples were collected from the jugular vein and placed into heparinized tubes. The samples were analyzed within 30 minutes of collection using a blood gas analyzer equipped with a cooximeter. Measurements and Main Results Greyhounds had significantly higher pH, PO2, oxygen saturation, oxyhemoglobin, total Hb, oxygen content, and oxygen capacity and significantly lower deoxyhemoglobin and P50 when compared with non-Greyhound dogs. Conclusion These findings support the fact that this breed is able to carry a higher concentration of total oxygen in the blood. As reported previously, this breed also has lower P50 and, therefore, high oxygen affinity. In light of recent findings suggesting that in certain tissues a high affinity for oxygen is beneficial, this adaptation may be of benefit during strenuous exercise. PMID:21288290

  8. Stochastic PArallel Rarefied-gas Time-accurate Analyzer

    SciTech Connect

    Michael Gallis, Steve Plimpton

    2014-01-24

    The SPARTA package is software for simulating low-density fluids via the Direct Simulation Monte Carlo (DSMC) method, which is a particle-based method for tracking particle trajectories and collisions as a model of a multi-species gas. The main component of SPARTA is a simulation code which allows the user to specify a simulation domain, populate it with particles, embed triangulated surfaces as boundary conditions for the flow, overlay a grid for finding pairs of collision partners, and evolve the system in time via explicit timestepping. The package also includes various pre- and post-processing tools, useful for setting up simulations and analyzing the results. The simulation code runs either in serial on a single processor or desktop machine, or can be run in parallel using the MPI message-passing library, to enable faster performance on large problems.

  9. Stochastic PArallel Rarefied-gas Time-accurate Analyzer

    Energy Science and Technology Software Center (ESTSC)

    2014-01-24

    The SPARTA package is software for simulating low-density fluids via the Direct Simulation Monte Carlo (DSMC) method, which is a particle-based method for tracking particle trajectories and collisions as a model of a multi-species gas. The main component of SPARTA is a simulation code which allows the user to specify a simulation domain, populate it with particles, embed triangulated surfaces as boundary conditions for the flow, overlay a grid for finding pairs of collision partners,more » and evolve the system in time via explicit timestepping. The package also includes various pre- and post-processing tools, useful for setting up simulations and analyzing the results. The simulation code runs either in serial on a single processor or desktop machine, or can be run in parallel using the MPI message-passing library, to enable faster performance on large problems.« less

  10. INGAS: Iranian Noble Gas Analyzing System for radioxenon measurement

    NASA Astrophysics Data System (ADS)

    Doost-Mohammadi, V.; Afarideh, H.; Etaati, G. R.; Safari, M. J.; Rouhi, H.

    2016-03-01

    In this article, Iranian Noble Gas Analyzing System (INGAS) will be introduced. This system is based on beta-gamma coincidence technique and consists of a well-type NaI(Tl) as gamma or X radiation detector and a cylindrical plastic scintillator to detect beta or conversion electron. Standard NIM modules were utilized to detect coincidence events of detectors. Both the beta and gamma detectors were appropriately calibrated. The efficiency curve of gamma detector for volume geometry was obtained by comparing the results of gamma point sources measurements and simulations of GATE V7.0 Monte Carlo code. The performance of detection system was checked by injection of 222Rn and 131mXe gaseous source in the detection cell. The minimum detectable activity of the system for 133Xe is 1.240±0.024 mBq for 24 h measurement time.

  11. Phoenix Mars Mission--the thermal evolved gas analyzer.

    PubMed

    Hoffman, John H; Chaney, Roy C; Hammack, Hilton

    2008-10-01

    The Phoenix spacecraft that was launched to Mars in August 2007 landed safely on the Martian northern arctic region on May 25, 2008. It carried six experiments to study the history of water on the planet and search for organic molecules in the icy subsurface Martian soil. The spacecraft is a lander with an arm and scoop designed to dig a trench though the top soil to reach an expected ice layer near the surface. One of the instruments on board is the thermal evolved gas analyzer (TEGA), which consists of two components, a set of eight very small ovens that will heat samples of the ice soil mixtures from the trench to release imbedded gases and mineral decomposition products, and a mass spectrometer that serves as the analysis tool for the evolved gases, and also for measurements of the composition and isotopic ratios of the gases that comprise the atmosphere of Mars. The mass spectrometer is a miniature magnetic sector instrument controlled by microprocessor-driven power supplies. One feature is the gas enrichment cell that will increase the partial pressures of the noble gases in an atmosphere sample by removing all the active gases, carbon dioxide, and nitrogen, to improve the accuracy of their isotopic ratio measurements. PMID:18715800

  12. A modified photo- and magnetoacoustic multigas analyzer applied in gas exchange measurements.

    PubMed

    Clemensen, P; Christensen, P; Norsk, P; Grønlund, J

    1994-06-01

    The feasibility of replacing a conventional mass spectrometer (MS) with a specially modified multicomponent (O2, CO2, Freon 22, and SF6) acoustic infrared and paramagnetic (IR/PM) gas analyzer in inert gas-rebreathing and metabolic gas exchange measurements has been investigated. Rebreathing variables were determined simultaneously with the MS and IR/PM analyzers in duplicate measurements at rest and during submaximal exercise in 10 subjects. The differences (means +/- SD, IR/PM - MS) were 0.028 +/- 0.048 liters [functional residual capacity (FRC)], 0.18 +/- 0.38 l/min [cardiac output (Qc)], -0.006 +/- 0.030 l/min [O2 consumption (VO2)], and -33 +/- 108 ml [combined lung tissue and capillary blood volume (Vti,c)]. The coefficients of variation on repeated estimates were 5.8% (FRC), 5.4% (Qc), 6.2% (VO2), and 17% (Vti,c) with the IR/PM analyzer and 5.9% (FRC), 4.2% (Qc), 5.0% (VO2), and 9.8% (Vti,c) with the MS. The differences (IR/PM - MS) obtained in mixed-expirate measurements were -0.006 +/- 0.020 l/min (VO2) and 0.020 +/- 0.021 l/min (CO2 production). Breath-by-breath estimates of VO2 and CO2 production with the IR/PM analyzer were, on average, 2.4 and 4.4% higher than the MS estimates, respectively. Our results demonstrate that the IR/PM gas analyzer, when appropriately modified, can substitute for a complex MS in a variety of noninvasive pulmonary gas exchange measurements. PMID:7928918

  13. Analyzing Illumina Gene Expression Microarray Data Obtained From Human Whole Blood Cell and Blood Monocyte Samples.

    PubMed

    Teumer, Alexander; Schurmann, Claudia; Schillert, Arne; Schramm, Katharina; Ziegler, Andreas; Prokisch, Holger

    2016-01-01

    Microarray profiling of gene expression is widely applied to studies in molecular biology and functional genomics. Experimental and technical variations make not only the statistical analysis of single studies but also meta-analyses of different studies very challenging. Here, we describe the analytical steps required to substantially reduce the variations of gene expression data without affecting true effect sizes. A software pipeline has been established using gene expression data from a total of 3358 whole blood cell and blood monocyte samples, all from three German population-based cohorts, measured on the Illumina HumanHT-12 v3 BeadChip array. In summary, adjustment for a few selected technical factors greatly improved reliability of gene expression analyses. Such adjustments are particularly required for meta-analyses of different studies. PMID:26614070

  14. Using Willie's Acid-Base Box for Blood Gas Analysis

    ERIC Educational Resources Information Center

    Dietz, John R.

    2011-01-01

    In this article, the author describes a method developed by Dr. William T. Lipscomb for teaching blood gas analysis of acid-base status and provides three examples using Willie's acid-base box. Willie's acid-base box is constructed using three of the parameters of standard arterial blood gas analysis: (1) pH; (2) bicarbonate; and (3) CO[subscript…

  15. Laser gas analyzers for studying kinetics of gas exchange between vegetation biosystems and atmosphere

    NASA Astrophysics Data System (ADS)

    Ageev, B. G.; Kapitanov, V. A.; Ponomarev, Yu. N.; Vasiliev, V. A.; Karapuzikov, A. I.; Sherstov, I. V.

    2006-11-01

    Specifications and examples of application of laser gas-analyzers of near- and mid-infrared ranges for diagnostics of greenhouse gases (CO II, C IIH 4, and CH 4) emission by vegetation biosystems both under standard conditions and under impacts of natural and anthropogenic stresses are considered in the report. The gas-analyzer complex includes: 1) gas-analyzer with a multipass absorption cell based on the frequency-tunable diode laser (1600-1650 nm) for measuring sub-background methane concentrations (<= 20 ppbV); 2) gas-analyzer based on the wave-guide CO II-laser equipped with the intracavity acoustic detector capable of fast frequency scanning in the 9 and 10 μm generation bands and having the ethylene-sensitivity better than 1 ppbV. The technology of measurements of gas emission by plant stripped leaves and coniferous needles is described and the measurements of CO II and CH 4 emissions are presented.

  16. Laser gas-analyzers for studying kinetics of gas-exchange between vegetation biosystems and atmosphere

    NASA Astrophysics Data System (ADS)

    Ageev, B. G.; Kapitanov, V. A.; Ponomarev, Yu. N.; Vasiliev, V. A.; Karapuzikov, A. I.; Sherstov, I. V.

    2006-12-01

    Specifications and examples of application of laser gas-analyzers of near- and mid-infrared ranges for diagnostics of greenhouse gases (C0 II, C IIH 4, and CH 4) emission by vegetation biosystems both under standard conditions and under impacts of natural and anthropogenic stresses are considered in the report. The gas-analyzer complex includes: 1) gas-analyzer with a multipass absorption cell based on the frequency-tunable diode laser (1600-1 650 nm) for measuring sub-background methane concentrations (<=20 ppbV); 2) gas-analyzer based on the wave-guide C0 II-laser equipped with the intracavity acoustic detector capable of fast frequency scanning in the 9 and 10 μm generation bands and having the ethylene-sensitivity better than 1 ppbV. The technology of measurements of gas emission by plant stripped leaves and coniferous needles is described and the measurements of CO II and CH 4 emissions are presented.

  17. Analyzing the influence of combustion gas on a gas turbine by radiation thermometry

    NASA Astrophysics Data System (ADS)

    Gao, Shan; Wang, Lixin; Feng, Chi; Kipngetich, Ketui Daniel

    2015-11-01

    High temperature is the main focus in ongoing development of gas turbines. With increasing turbine inlet temperature, turbine blades undergo complex thermal and structural loading subjecting them to large thermal gradients and, consequently, severe thermal stresses and strain. In order to improve the reliability, safety, and service life of blades, accurate measurement of turbine blade temperature is necessary. A gas turbine can generate high-temperature and high-pressure gas that interferes greatly with radiation from turbine blades. In addition, if the gas along the optical path is not completely transparent, blade temperature measurement is subject to significant measurement error in the gas absorption spectrum. In this study, we analyze gas turbine combustion gases using the κ-distribution method combined with the HITEMP and HITRAN databases to calculate the transmission and emissivity of mixed gases. We propose spectral window methods to analyze the radiation characteristics of high-temperature gas under different spectral ranges, which can be used to select the wavelengths used in multispectral temperature measurement on turbine blades and estimate measurement error in the part of the spectrum with smaller influence (transmission > 0.98).

  18. Aging stability of complete blood count and white blood cell differential parameters analyzed by Abbott CELL-DYN Sapphire hematology analyzer.

    PubMed

    Hedberg, P; Lehto, T

    2009-02-01

    This study presents the results of an aging stability study of complete blood count (CBC) and leukocyte differential parameters using the Abbott CELL-DYN Sapphire hematology analyzer. Stability studies showed no substantial change in CBC parameters up to 24-48 h at +23 +/- 2 degrees C (room temperature), except for optical platelet count (PLTo). For specimens aged over 24, the value of impedance platelet count yielded more reliable results than the routine PLTo. White blood cell (WBC) differential parameters, except eosinophils, were stable for up to 48 h at +23 +/- 2 degrees C. CBC parameters were stable for 72 h, except mean platelet volume, which slightly increased between 48 and 72 h, at +4 degrees C. WBC differentials were stable 48-72 h, with a slight decrease observed in absolute neutrophils and lymphocytes at +4 degrees C. PMID:18190587

  19. Detection of atmospheric trace gas species by DOAS gas-analyzer

    NASA Astrophysics Data System (ADS)

    Geiko, Pavel P.; Smirnov, Sergey S.; Samokhvalov, Ignatii V.

    2014-11-01

    A differential optical absorption spectroscopy (DOAS) gas-analyzer was successfully tested. A high pressure 150-W Xe arc lamp was employed as a light source This system consisted of a coaxial telescope, a spectrometer, an analyzer and retroreflector. In order to record the spectra, a monochrometer with a grating and photodiode array was adopted. Gas analyzer spectral data bank includes more than 30 moleculas absorbed in UV spectral region. The measured absorption spectra were evaluated by using a least-squares fit to determine the average mixing ratio of each species in the atmosphere. A number of air pollutants concentrations: SO2, NO2, O3, etc were trace measured. Minimally detected concentration on pathlength 400 m is the unit of ppb at the time of accumulation of 2 min. The results of the field test measurements of pollutants in Tomsk are presented.

  20. Blood gas analysis as a determinant of occupationally related disability

    SciTech Connect

    Morgan, W.K.; Zaldivar, G.L. )

    1990-05-01

    Arterial blood gas analysis is one of the criteria used by the Department of Labor to award total and permanent disability for coal workers' pneumoconiosis (Black Lung). We have observed that Black Lung claimants often undergo several blood gas analyses with widely differing results that sometimes range from complete normality to life-threatening hypoxemia in the same subject. We concluded that blood gas analysis in occupationally related disability determination is unreliable, in that quality control and instrumentation are variable; that severe hypoxemia is rare in coal workers' pneumoconiosis; and that such hypoxemia is nonspecific and correlates poorly with breathlessness.

  1. Low-Power Architecture for an Optical Life Gas Analyzer

    NASA Technical Reports Server (NTRS)

    Pilgrim, Jeffrey; Vakhtin, Andrei

    2012-01-01

    Analog and digital electronic control architecture has been combined with an operating methodology for an optical trace gas sensor platform that allows very low power consumption while providing four independent gas measurements in essentially real time, as well as a user interface and digital data storage and output. The implemented design eliminates the cross-talk between the measurement channels while maximizing the sensitivity, selectivity, and dynamic range for each measured gas. The combination provides for battery operation on a simple camcorder battery for as long as eight hours. The custom, compact, rugged, self-contained design specifically targets applications of optical major constituent and trace gas detection for multiple gases using multiple lasers and photodetectors in an integrated package.

  2. A gas chromatographic air analyzer fabricated on a silicon wafer

    NASA Technical Reports Server (NTRS)

    Terry, S. C.; Jerman, J. H.; Angell, J. B.

    1979-01-01

    A miniature gas analysis system has been built based on the principles of gas chromatography (GC). The major components are fabricated in silicon using photolithography and chemical etching techniques, which allows size reductions of nearly three orders of magnitude compared to conventional laboratory instruments. The chromatography system consists of a sample injection valve and a 1.5-m-long separating capillary column, which are fabricated on a substrate silicon wafer. The output thermal conductivity detector is separately batch fabricated and integrably mounted on the substrate wafer. The theory of gas chromatography has been used to optimize the performance of the sensor so that separations of gaseous hydrocarbon mixtures are performed in less than 10 s. The system is expected to find application in the areas of portable ambient air quality monitors, implanted biological experiments, and planetary probes.

  3. Application of interferometry in analyzing gas flow in microchannels

    NASA Astrophysics Data System (ADS)

    Li, Yongli; Newport, David; Joseph, Shiju; Brandner, Juergen J.

    2011-11-01

    Interferometry is a noninvasive measurement and based on this technique, the measurement or visualization of changes in physical properties of transparent objects can be achieved by detecting the refractive index changes. Gas pressure and temperature can be related to their refractive index, so interferometry can be used for local measurement of changes of these properties along the channel. A Mach-Zehnder interferometer was built with a laser with a wavelength of 633 nm, a high speed camera and two acousto-optic modulators (AOMs). Due to small channel characteristic length and sometimes low gas pressure, the measurement could be much influenced by noise. The AOMs can introduce frequency shifts into the system by acousto-optic effect, which can avoid mechanical noise generally by translating piezoelectric mirrors. The channel sides with optical access are made from crystalline silica (Quartz) that does not show speckle effects and any laser absorbance. For initial tests, the local gas pressure drop distribution along microchannel is studied at room temperature. The research leading to these results has received funding from the European Community's Seventh Framework Programme (ITN - FP7/2007-2013) under grant agreement no. 215504.

  4. Gas signatures from Escherichia coli and Escherichia coli-inoculated human whole blood

    PubMed Central

    2013-01-01

    Background The gaseous headspace above naïve Escherichia Coli (E. coli) cultures and whole human blood inoculated with E. coli were collected and analyzed for the presence of trace gases that may have the potential to be used as novel, non-invasive markers of infectious disease. Methods The naïve E. coli culture, LB broth, and human whole blood or E. coli inoculated whole blood were incubated in hermetically sealable glass bioreactors at 37°C for 24 hrs. LB broth and whole human blood were used as controls for background volatile organic compounds (VOCs). The headspace gases were collected after incubation and analyzed using a gas chromatographic system with multiple column/detector combinations. Results Six VOCs were observed to be produced by E. coli-infected whole blood while there existed nearly zero to relatively negligible amounts of these gases in the whole blood alone, LB broth, or E. coli-inoculated LB broth. These VOCs included dimethyl sulfide (DMS), carbon disulfide (CS2), ethanol, acetaldehyde, methyl butanoate, and an unidentified gas S. In contrast, there were several VOCs significantly elevated in the headspace above the E. coli in LB broth, but not present in the E. coli/blood mixture. These VOCs included dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), methyl propanoate, 1-propanol, methylcyclohexane, and unidentified gases R2 and Q. Conclusions This study demonstrates 1) that cultivated E. coli in LB broth produce distinct gas profiles, 2) for the first time, the ability to modify E. coli-specific gas profiles by the addition of whole human blood, and 3) that E. coli-human whole blood interactions present different gas emission profiles that have the potential to be used as non-invasive volatile biomarkers of E. coli infection. PMID:23842518

  5. Rapid Point of Care Analyzer for the Measurement of Cyanide in Blood

    PubMed Central

    Ma, Jian; Ohira, Shin-Ichi; Mishra, Santosh K.; Puanngam, Mahitti; Dasgupta, Purnendu K.; Mahon, Sari B.; Brenner, Matthew; Blackledge, William; Boss, Gerry R.

    2011-01-01

    A simple, sensitive optical analyzer for the rapid determination of cyanide in blood in point of care applications is described. HCN is liberated by the addition of 20% H3PO4 and is absorbed by a paper filter impregnated with borate-buffered (pH 9.0) hydroxoaquocobinamide Hereinafter called cobinamide). Cobinamide on the filter changes color from orange (λmax = 510 nm) to violet (λmax = 583 nm) upon reaction with cyanide. This color change is monitored in the transmission mode by a light emitting diode (LED) with a 583 nm emission maximum and a photodiode detector. The observed rate of color change increases 10x when the cobinamide solution for filter impregnation is prepared in borate-buffer rather than in water. The use of a second LED emitting at 653 nm and alternate pulsing of the LEDs improve the limit of detection by 4x to ~ 0.5 μM for a 1 mL blood sample. Blood cyanide levels of imminent concern (≥ 10 μM) can be accurately measured in ~ 2 min. The response is proportional to the mass of cyanide in the sample – smaller sample volumes can be successfully used with proportionate change in the concentration LODs. Bubbling air through the blood-acid mixture was found effective for mixing of the acid with the sample and the liberation of HCN. A small amount of ethanol added to the top of the blood was found to be the most effective means to prevent frothing during aeration. The relative standard deviation (RSD) for repetitive determination of blood samples containing 9 μM CN was 1.09% (n=5). The technique was compared blind with a standard microdiffusion-spectrophotometric method used for the determination of cyanide in rabbit blood. The results showed good correlation (slope 1.05, r2 0.9257); independent calibration standards were used. PMID:21553921

  6. 40 CFR 1065.309 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.309 Continuous... for water removed from the sample done in post-processing according to § 1065.659 (40 CFR 1066.620 for... ambient air drawn into the probe. We recommend you use the final, stabilized analyzer reading as the...

  7. Blood gas strategies and management during pediatric cardiopulmonary bypass.

    PubMed

    Griffin, Dee Ann

    2005-01-01

    Blood gas management during hypothermic cardiopulmonary bypass may be corrected by pH stat or alpha stat strategy. The pH stat philosophy is to maintain the blood pH constant at any temperature. Carbon dioxide must be introduced to the oxygenator in order to maintain the pH and pCO2 during hypothermic cardiopulmonary bypass. Conversely, during alpha stat blood gas management pH is maintained according to 37 degrees C despite the patient temperature. Alpha stat management preserves intracellular pH and autoregulation of cerebral vasculature by following the natural shift of the oxyhemoglobin dissociation curve. In-line blood gas analysis is a practical tool in assessing adequate blood gas management, because this technology provides immediate detection for modification of air/oxygen/carbon dioxide parameters. Results from several studies favor the pH stat strategy during neonatal cardiopulmonary bypass. This strategy increases tissue oxygenation and cerebral blood flow while cooling. Data also suggest that pH stat management results in better outcomes with shorter ventilation times and intensive care unit stays after pediatric cardiac surgery. PMID:16322734

  8. 21 CFR 870.4330 - Cardiopulmonary bypass on-line blood gas monitor.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cardiopulmonary bypass on-line blood gas monitor... Cardiopulmonary bypass on-line blood gas monitor. (a) Identification. A cardiopulmonary bypass on-line blood gas monitor is a device used in conjunction with a blood gas sensor to measure the level of gases in the...

  9. 21 CFR 870.4330 - Cardiopulmonary bypass on-line blood gas monitor.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass on-line blood gas monitor... Cardiopulmonary bypass on-line blood gas monitor. (a) Identification. A cardiopulmonary bypass on-line blood gas monitor is a device used in conjunction with a blood gas sensor to measure the level of gases in the...

  10. 21 CFR 870.4330 - Cardiopulmonary bypass on-line blood gas monitor.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cardiopulmonary bypass on-line blood gas monitor... Cardiopulmonary bypass on-line blood gas monitor. (a) Identification. A cardiopulmonary bypass on-line blood gas monitor is a device used in conjunction with a blood gas sensor to measure the level of gases in the...

  11. 21 CFR 870.4330 - Cardiopulmonary bypass on-line blood gas monitor.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cardiopulmonary bypass on-line blood gas monitor... Cardiopulmonary bypass on-line blood gas monitor. (a) Identification. A cardiopulmonary bypass on-line blood gas monitor is a device used in conjunction with a blood gas sensor to measure the level of gases in the...

  12. 21 CFR 870.4330 - Cardiopulmonary bypass on-line blood gas monitor.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cardiopulmonary bypass on-line blood gas monitor... Cardiopulmonary bypass on-line blood gas monitor. (a) Identification. A cardiopulmonary bypass on-line blood gas monitor is a device used in conjunction with a blood gas sensor to measure the level of gases in the...

  13. Arterial blood gas tensions and pH.

    PubMed Central

    Flenley, D C

    1980-01-01

    1 The definition of PO2 and its relationship to the oxygen saturation (SO2) by the oxygen dissociation curve (ODC) is described with details of the ligands of the ODC and the effects of haemoglobinopathies on P50 (the position of the ODC) and the slope of the ODC (Hill's 'n'). 2 The definition of PCO2 and description of CO2 transport by blood leads to consideration of the basis of acid base balance. 3 Acid base balance is expressed in terms of arterial blood (H+) (or pH) PCO2 relationship using a non-logarithmic diagram. 4 The measurement of arterial blood gas tensions is described with comments on arterial puncture and available modern automated blood gas electrodes and their calibration. 5 Non-invasive indirect measurements of blood gas tensions, by ear oximetry are described, with calibration figures on the Hewlett-Packard 47021A ear oximeter. End-tidal PO2 and PCO2 measurements by mass spectrometer or infra-red CO2 analyser, and of transcutaneous PO2 measurements by a heated polarographic electrode are described. 6 These measurements are necessary to study the effects of pharmacological agents on the chemical control of breathing, on pulmonary gas exchange, and on acid base balance in humans. The measurements are in everyday use in clinical practice, both to aid diagnosis of respiratory diseases, assess their severity, and to quantiate the effects of therapeutic agents. PMID:7356899

  14. 40 CFR 1065.550 - Gas analyzer range verification and drift verification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Gas analyzer range verification and drift verification. 1065.550 Section 1065.550 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Performing an Emission Test Over Specified Duty Cycles § 1065.550 Gas analyzer...

  15. 40 CFR 1065.550 - Gas analyzer range validation, drift validation, and drift correction.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Gas analyzer range validation, drift validation, and drift correction. 1065.550 Section 1065.550 Protection of Environment ENVIRONMENTAL... Over Specified Duty Cycles § 1065.550 Gas analyzer range validation, drift validation, and...

  16. 40 CFR 1065.550 - Gas analyzer range validation, drift validation, and drift correction.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Gas analyzer range validation, drift validation, and drift correction. 1065.550 Section 1065.550 Protection of Environment ENVIRONMENTAL... Over Specified Duty Cycles § 1065.550 Gas analyzer range validation, drift validation, and...

  17. [A gas chromatographic method for determining acetaldehyde in cadaver blood].

    PubMed

    Savich, V I; Valladares, Kh A; Gusakov, Iu A; Skachko, Z M

    1990-01-01

    Gas-chromatographic method of acetaldehyde detection in blood of subjects who died of alcoholic intoxication is suggested. Method is simple, does not require additional expenses, can be readily used in medicolegal practice and in difficult cases it may help the expert to make an objective conclusion on the cause of death. PMID:2087747

  18. 20 CFR 718.105 - Arterial blood-gas studies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 4 2012-04-01 2012-04-01 false Arterial blood-gas studies. 718.105 Section 718.105 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS, DEPARTMENT OF LABOR FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, AS AMENDED STANDARDS FOR DETERMINING COAL MINERS' TOTAL DISABILITY OR DEATH DUE TO PNEUMOCONIOSIS Criteria...

  19. 20 CFR 718.105 - Arterial blood-gas studies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 4 2013-04-01 2013-04-01 false Arterial blood-gas studies. 718.105 Section 718.105 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS, DEPARTMENT OF LABOR FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, AS AMENDED STANDARDS FOR DETERMINING COAL MINERS' TOTAL DISABILITY OR DEATH DUE TO PNEUMOCONIOSIS Criteria...

  20. 21 CFR 870.4410 - Cardiopulmonary bypass in-line blood gas sensor.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass in-line blood gas sensor... Cardiopulmonary bypass in-line blood gas sensor. (a) Identification. A cardiopulmonary bypass in-line blood gas sensor is a transducer that measures the level of gases in the blood. (b) Classification. Class...

  1. 21 CFR 870.4410 - Cardiopulmonary bypass in-line blood gas sensor.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cardiopulmonary bypass in-line blood gas sensor... Cardiopulmonary bypass in-line blood gas sensor. (a) Identification. A cardiopulmonary bypass in-line blood gas sensor is a transducer that measures the level of gases in the blood. (b) Classification. Class...

  2. 21 CFR 870.4410 - Cardiopulmonary bypass in-line blood gas sensor.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cardiopulmonary bypass in-line blood gas sensor... Cardiopulmonary bypass in-line blood gas sensor. (a) Identification. A cardiopulmonary bypass in-line blood gas sensor is a transducer that measures the level of gases in the blood. (b) Classification. Class...

  3. 21 CFR 870.4410 - Cardiopulmonary bypass in-line blood gas sensor.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cardiopulmonary bypass in-line blood gas sensor... Cardiopulmonary bypass in-line blood gas sensor. (a) Identification. A cardiopulmonary bypass in-line blood gas sensor is a transducer that measures the level of gases in the blood. (b) Classification. Class...

  4. 21 CFR 870.4410 - Cardiopulmonary bypass in-line blood gas sensor.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cardiopulmonary bypass in-line blood gas sensor... Cardiopulmonary bypass in-line blood gas sensor. (a) Identification. A cardiopulmonary bypass in-line blood gas sensor is a transducer that measures the level of gases in the blood. (b) Classification. Class...

  5. Rapid presumptive identification of anaerobes in blood cultures by gas-liquid chromatography.

    PubMed Central

    Sondag, J E; Ali, M; Murray, P R

    1980-01-01

    Production of volatile and nonvolatile metabolic acids in blood culture broths by aerobic, facultative anaerobic, and obligate anaerobic bacteria was analyzed by gas-liquid chromatography. Anaerobic blood culture isolates were presumptively identified by the qualitative analysis of volatile fatty acids. Isolates, with a characteristic Gram stain reaction and cellular morphology, were identified by the following acid patterns: Bacteriodes fragilis group with acetic and propionic acids; Fusobacterium with acetic, butyric, and usually propionic acids; Veillonella with acetic and propionic acids; gram-positive cocci with acetic and butyric acids; and Clostridium with acetic and butyric acids. PMID:7381002

  6. 28 CFR Appendix B to Part 79 - Blood-Gas Study Tables

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Blood-Gas Study Tables B Appendix B to... COMPENSATION ACT Pt. 79, App. B Appendix B to Part 79—Blood-Gas Study Tables For arterial blood-gas studies... mmHg 65 mmHg or below. Above 50 mmHg Any value. For arterial blood-gas studies performed at...

  7. 28 CFR Appendix B to Part 79 - Blood-Gas Study Tables

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Blood-Gas Study Tables B Appendix B to... COMPENSATION ACT Pt. 79, App. B Appendix B to Part 79—Blood-Gas Study Tables For arterial blood-gas studies... mmHg 65 mmHg or below. Above 50 mmHg Any value. For arterial blood-gas studies performed at...

  8. 28 CFR Appendix B to Part 79 - Blood-Gas Study Tables

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Blood-Gas Study Tables B Appendix B to... COMPENSATION ACT Pt. 79, App. B Appendix B to Part 79—Blood-Gas Study Tables For arterial blood-gas studies... mmHg 65 mmHg or below. Above 50 mmHg Any value. For arterial blood-gas studies performed at...

  9. 28 CFR Appendix B to Part 79 - Blood-Gas Study Tables

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Blood-Gas Study Tables B Appendix B to... COMPENSATION ACT Pt. 79, App. B Appendix B to Part 79—Blood-Gas Study Tables For arterial blood-gas studies... mmHg 65 mmHg or below. Above 50 mmHg Any value. For arterial blood-gas studies performed at...

  10. 20 CFR Appendix C to Part 718 - Blood-Gas Tables

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Blood-Gas Tables C Appendix C to Part 718... DUE TO PNEUMOCONIOSIS Pt. 718, App. C Appendix C to Part 718—Blood-Gas Tables The following tables set... of the following tables are met: (1) For arterial blood-gas studies performed at test sites up to...

  11. 20 CFR Appendix C to Part 718 - Blood-Gas Tables

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 4 2012-04-01 2012-04-01 false Blood-Gas Tables C Appendix C to Part 718... DUE TO PNEUMOCONIOSIS Pt. 718, App. C Appendix C to Part 718—Blood-Gas Tables The following tables set... of the following tables are met: (1) For arterial blood-gas studies performed at test sites up to...

  12. 20 CFR Appendix C to Part 718 - Blood-Gas Tables

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 4 2013-04-01 2013-04-01 false Blood-Gas Tables C Appendix C to Part 718... DUE TO PNEUMOCONIOSIS Pt. 718, App. C Appendix C to Part 718—Blood-Gas Tables The following tables set... of the following tables are met: (1) For arterial blood-gas studies performed at test sites up to...

  13. Arterial blood gas reference values for sea level and an altitude of 1,400 meters.

    PubMed

    Crapo, R O; Jensen, R L; Hegewald, M; Tashkin, D P

    1999-11-01

    Blood gas measurements were collected on healthy lifetime nonsmokers at sea level (n = 96) and at an altitude of 1,400 meters (n = 243) to establish reference equations. At each study site, arterial blood samples were analyzed in duplicate on two separate blood gas analyzers and CO-oximeters. Arterial blood gas variables included Pa(O(2)), Pa(CO(2)), pH, and calculated alveolar-arterial PO(2) difference (AaPO(2)). CO-oximeter variables were Hb, COHb, MetHb, and Sa(O(2)). Subjects were 18 to 81 yr of age with 166 male and 173 female. Outlier data were excluded from multiple regression analysis, and reference equations were fitted to the data in two ways: (1) best fit using linear, squared, and cross-product terms; (2) simple equations, including only the variables that explained at least 3% of the variance. Two sets of equations were created: (1) using only the sea level data and (2) using the combined data with barometric pressure as an independent variable. Comparisons with earlier studies revealed small but significant differences; the decline in Pa(O(2)) with age at each altitude was consistent with most previous studies. At sea level, the equation that included barometric pressure predicted Pa(O(2)) slightly better than the sea level specific equation. The inclusion of barometric pressure in the equations allows better prediction of blood gas reference values at sea level and at altitudes as high as 1,400 meters. PMID:10556115

  14. Oxygen tension measurement using an automatic blood gas analyser1

    PubMed Central

    Becket, J; Chakrabarti, M K; Gillies, I D S; Orchard, C; Hall, G M; Bourdillon, P J

    1981-01-01

    Two different methods of assessing the reliability of the oxygen electrode of one model of an automatic blood gas analyser (BGA) have been studied. In the first, a single automatic BGA was assessed by using outdated bank blood which was pumped around a small extracorporeal circuit into which known gas mixtures were passed. Oxygen tension was varied between 2 and 16 kPa. In the second, fresh heparinized blood was tonometered with calibrated gases and submitted to the automatic BGA used in the first part of the study and also to three other identical machines. Each of the machines was between 3 and 4 years old. Eighteen different units of blood were used in the first part of the study. The correlation coefficient between the automatic BGA and the Po2 in the extracorporeal circuit varied between 0.29 and 0.99. 31% of the total of 209 measurements made by the automatic BGA were more than 1.2 kPa from the reference value, 25% of them being between 1.2 and 4.0 kPa from the reference value. In the second part of the study, the correlation coefficient between this automatic BGA and the tonometered blood was 0.96. The correlation coefficients for the 3 other identical BGAs were 0.84, 0.97 and 0.88, indicating that the BGA used in the first part of the study was no worse than any of the others. It is suggested that although clinicians are likely to ignore readings of an automatic BGA that are more than 4.0 kPa from the true value and are likely to repeat the investigation, readings between 1.2 and 4.0 kPa from the true value may adversely affect patient management. PMID:7288796

  15. Oxygen tension measurement using an automatic blood gas analyser.

    PubMed

    Becket, J; Orchard, C; Chakrabarti, M K; Hall, G M; Gillies, I D; Bourdillon, P J

    1981-08-01

    Two different methods of assessing the reliability of the oxygen electrode of one model of an automatic blood gas analyser (BGA) have been studied. In the first, a single automatic BGA was assessed by using outdated bank blood which was pumped around a small extracorporeal circuit into which known gas mixtures were passed. Oxygen tension was varied between 2 and 16 kPa. In the second, fresh heparinized blood was tonometered with calibrated gases and submitted to the automatic BGA used in the first part of the study and also to three other identical machines. Each of the machines was between 3 and 4 years old.Eighteen different units of blood were used in the first part of the study. The correlation coefficient between the automatic BGA and the Po(2) in the extracorporeal circuit varied between 0.29 and 0.99. 31% of the total of 209 measurements made by the automatic BGA were more than 1.2 kPa from the reference value, 25% of them being between 1.2 and 4.0 kPa from the reference value. In the second part of the study, the correlation coefficient between this automatic BGA and the tonometered blood was 0.96. The correlation coefficients for the 3 other identical BGAs were 0.84, 0.97 and 0.88, indicating that the BGA used in the first part of the study was no worse than any of the others.It is suggested that although clinicians are likely to ignore readings of an automatic BGA that are more than 4.0 kPa from the true value and are likely to repeat the investigation, readings between 1.2 and 4.0 kPa from the true value may adversely affect patient management. PMID:7288796

  16. The Laser-assisted Optical Rotational Cell Analyzer (LORCA) as red blood cell aggregometer.

    PubMed

    Hardeman, M R; Dobbe, J G; Ince, C

    2001-01-01

    The Laser-assisted Optical Rotational Cell Analyzer (LORCA) is unique in its capacity to measure at least two important hemorheological parameters, i.e., deformability of red blood cells (RBC) as well as their aggregation behaviour. In this communication the main principles and characteristics of the aggregometer mode of this instrument are described. Via syllectometry (i.e., laser backscatter versus time), the method allows the measure of both static and kinetic parameters of the aggregation process, e.g., total extent of aggregation, aggregation half time and a combination of these, defined as aggregation index. When the syllectogram deviates from that representing normal rouleaux formation, e.g., in the case of RBC clump formation, this is signalled by a fit error. Maximal flexibility is obtained by various options like an automated re-iteration procedure (which enables to measure the aggregation tendency and/or the aggregate stability) and aggregation at low shear rate. Experiments dealing with reproducibility, stability and sensitivity of the instrument are described. The latter include a few "classic" methods for inducing subtle changes in RBC aggregation behaviour both regarding cellular factors (heat treatment) and changes in medium constituents (fibrinogen, dextrans).It can be concluded that the aggregometer mode of the LORCA considerably increases the feasibility of this instrument for hemorheological investigations. PMID:11790865

  17. Gas chromatographic and mass spectrometric analysis of polychlorinated biphenyls in human placenta and cord blood

    SciTech Connect

    Ando, M.; Saito, H.; Wakisaka, I.

    1986-10-01

    Gas chromatographic and mass spectrometric analyses of polychlorinated biphenyls (PCBs) in placenta, maternal blood, cord blood, and milk were carried out. Trichlorobiphenyl, tetrachlorobiphenyl, pentachlorobiphenyls, and hexachlorobiphenyls were identified by the mass chromatogram and the mass spectra. Some minor peaks of PCBs were identified by gas chromatography. The relationship between the PCB concentration in placenta and that in milk is different in each PCB congener. The higher the chlorine content of the PCB congener, the more significant the correlation. No significant but a low negative correlation exists between the concentration of some PCB congeners in the placenta and that in cord blood. On the other hand, a significant linear correlation exists between the concentration of hexachlorobenzene in the placenta and that in cord blood. The transplacental transport of each PCB congener varied depending upon its chemical nature. Trichlorobiphenyl and tetrachlorobiphenyl were more transferable than hexachlorobiphenyls. The results show that the placenta and cord blood are useful human samples to analyze the body burden of environmental pollutants and to estimate their transfer from mother to fetus.

  18. Method and apparatus for automated processing and aliquoting of whole blood samples for analysis in a centrifugal fast analyzer

    DOEpatents

    Burtis, Carl A.; Johnson, Wayne F.; Walker, William A.

    1988-01-01

    A rotor and disc assembly for use in a centrifugal fast analyzer. The assembly is designed to process multiple samples of whole blood followed by aliquoting of the resultant serum into precisely measured samples for subsequent chemical analysis. The assembly requires minimal operator involvement with no mechanical pipetting. The system comprises (1) a whole blood sample disc, (2) a serum sample disc, (3) a sample preparation rotor, and (4) an analytical rotor. The blood sample disc and serum sample disc are designed with a plurality of precision bore capillary tubes arranged in a spoked array. Samples of blood are loaded into the blood sample disc in capillary tubes filled by capillary action and centrifugally discharged into cavities of the sample preparation rotor where separation of serum and solids is accomplished. The serum is loaded into the capillaries of the serum sample disc by capillary action and subsequently centrifugally expelled into cuvettes of the analytical rotor for analysis by conventional methods.

  19. Comparative usefulness of inflammatory markers to indicate bacterial infection-analyzed according to blood culture results and related clinical factors.

    PubMed

    Nishikawa, Hirokazu; Shirano, Michinori; Kasamatsu, Yu; Morimura, Ayumi; Iida, Ko; Kishi, Tomomi; Goto, Tetsushi; Okamoto, Saki; Ehara, Eiji

    2016-01-01

    To assess relationships of inflammatory markers and 2 related clinical factors with blood culture results, we retrospectively investigated inpatients' blood culture and blood chemistry findings that were recorded from January to December 2014 using electronic medical records and analyzed the data of 852 subjects (426 culture-positive and 426 culture-negative). Results suggested that the risk of positive blood culture statistically increased as inflammatory marker levels and the number of related factors increased. Concerning the effectiveness of inflammatory markers, when the outcome definition was also changed for C-reactive protein (CRP), the odds ratio had a similar value, whereas when the outcome definition of blood culture positivity was used for procalcitonin (PCT), the greatest effectiveness of that was detected. Therefore, the current results suggest that PCT is more useful than CRP as an auxiliary indication of bacterial infection. PMID:26525643

  20. Method and apparatus for automated processing and aliquoting of whole blood samples for analysis in a centrifugal fast analyzer

    DOEpatents

    Burtis, C.A.; Johnson, W.F.; Walker, W.A.

    1985-08-05

    A rotor and disc assembly for use in a centrifugal fast analyzer. The assembly is designed to process multiple samples of whole blood followed by aliquoting of the resultant serum into precisely measured samples for subsequent chemical analysis. The assembly requires minimal operator involvement with no mechanical pipetting. The system comprises: (1) a whole blood sample disc; (2) a serum sample disc; (3) a sample preparation rotor; and (4) an analytical rotor. The blood sample disc and serum sample disc are designed with a plurality of precision bore capillary tubes arranged in a spoked array. Samples of blood are loaded into the blood sample disc by capillary action and centrifugally discharged into cavities of the sample preparation rotor where separation of serum and solids is accomplished. The serum is loaded into the capillaries of the serum sample disc by capillary action and subsequently centrifugally expelled into cuvettes of the analyticaly rotor for conventional methods. 5 figs.

  1. Application to cows and horses of Spotchem, a dry-chemistry blood analyzer for use in veterinary clinics.

    PubMed

    Hoshi, F; Satho, M; Koyama, S; Nakadaka, K; Chiba, M; Ikeda, N; Hakamada, R; Higuchi, S; Kawamura, S

    1994-02-01

    The usefulness of a dry-chemistry blood analyzer, Spotchem SP-4410 (SP-4410) in a veterinary clinic for analysis of bovine and equine blood chemistry was studied. We quantitated total protein (TP), albumin (Alb), total bilirubin (T-Bil), blood urea nitrogen (BUN), total cholesterol (T-Cho), glucose (Glu), calcium (Ca), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), creatinine phosphokinase (CPK), and alkaline phosphatase (ALP) in bovine sera. Each sample was assayed with both the SP-4410 and an automated blood analyzer which served as a wet-chemistry reference system, and the data were analyzed with regression analysis. The correlation coefficient for AST was 0.997 being the highest for all the parameters, and all the correlation coefficients were 0.93 or higher. The coefficients of variation were lower than 5.0 except in the case of bovine T-Bil where it was 5,756. The ranges of normal reference values measured by SP-4410 were the same as those reported by other investigators in most cases, but those for GGT and CPK were slightly higher. The strongest interference was observed with hemoglobin. It seems that dry-chemical-analysis of blood serum using the SP-4410 is useful for analysis of bovine and equine blood. PMID:8085395

  2. Thermal and Evolved Gas Analyses at Reduced Pressures: A Mineral Database for the Thermal Evolved Gas Analyzer (TEGA)

    NASA Technical Reports Server (NTRS)

    Lauer, H. V., Jr.; Ming, Douglas W.; Golden, D. C.; Lin, I.-C.; Morris, R. V.; Boynton, W. V.

    2000-01-01

    Volatile-bearing minerals (e.g., Fe-oxyhydroxides, phyllosilicates, carbonates, and sulfates) may be important phases on the surface of Mars. The Thermal Evolved Gas Analyzer (TEGA), which was part of the Mars Polar Lander payload, was to detect and identify volatile-bearing phases in the Martian regolith. The TEGA instrument is composed of a differential scanning calorimetry (DSC) interfaced with an evolved gas analyzer (EGA). The EGA consists of a Herriott cell of a tunable-diode laser (TDL) spectrometer that determines CO, and H2O abundances. The sample chamber in TEGA operates at about 100 mbar (-76 torr) with a N2 carrier gas flow of 0.4 sccm. Essentially no information exists on the effects of reduced pressure on the thermal properties of volatile-bearing minerals. Here we present a database for the thermal behavior of volatile-bearing phases under reduced pressure conditions.

  3. Field intercomparison of four methane gas analyzers suitable for eddy covariance flux measurements

    NASA Astrophysics Data System (ADS)

    Peltola, O.; Mammarella, I.; Haapanala, S.; Burba, G.; Vesala, T.

    2013-06-01

    Performances of four methane gas analyzers suitable for eddy covariance measurements are assessed. The assessment and comparison was performed by analyzing eddy covariance data obtained during summer 2010 (1 April to 26 October) at a pristine fen, Siikaneva, Southern Finland. High methane fluxes with pronounced seasonality have been measured at this fen. The four participating methane gas analyzers are commercially available closed-path units TGA-100A (Campbell Scientific Inc., USA), RMT-200 (Los Gatos Research, USA), G1301-f (Picarro Inc., USA) and an early prototype open-path unit Prototype-7700 (LI-COR Biosciences, USA). The RMT-200 functioned most reliably throughout the measurement campaign, during low and high flux periods. Methane fluxes from RMT-200 and G1301-f had the smallest random errors and the fluxes agree remarkably well throughout the measurement campaign. Cospectra and power spectra calculated from RMT-200 and G1301-f data agree well with corresponding temperature spectra during a high flux period. None of the gas analyzers showed statistically significant diurnal variation for methane flux. Prototype-7700 functioned only for a short period of time, over one month, in the beginning of the measurement campaign during low flux period, and thus, its overall accuracy and season-long performance were not assessed. The open-path gas analyzer is a practical choice for measurement sites in remote locations due to its low power demand, whereas for G1301-f methane measurements interference from water vapor is straightforward to correct since the instrument measures both gases simultaneously. In any case, if only the performance in this intercomparison is considered, RMT-200 performed the best and is the recommended choice if a new fast response methane gas analyzer is needed.

  4. Industrial SO2 emission monitoring through a portable multichannel gas analyzer with an optimized retrieval algorithm

    NASA Astrophysics Data System (ADS)

    Sun, Youwen; Liu, Cheng; Xie, Pinhua; Hartl, Andreas; Chan, Kalok; Tian, Yuan; Wang, Wei; Qin, Min; Liu, Jianguo; Liu, Wenqing

    2016-03-01

    SO2 variability over a large concentration range and interferences from other gases have been major limitations in industrial SO2 emission monitoring. This study demonstrates accurate industrial SO2 emission monitoring through a portable multichannel gas analyzer with an optimized retrieval algorithm. The proposed analyzer features a large dynamic measurement range and correction of interferences from other coexisting infrared absorbers such as NO, CO, CO2, NO2, CH4, HC, N2O, and H2O. The multichannel gas analyzer measures 11 different wavelength channels simultaneously to correct several major problems of an infrared gas analyzer including system drift, conflict of sensitivity, interferences among different infrared absorbers, and limitation of measurement range. The optimized algorithm uses a third polynomial instead of a constant factor to quantify gas-to-gas interference. Measurement results show good performance in the linear and nonlinear ranges, thereby solving the problem that the conventional interference correction is restricted by the linearity of the intended and interfering channels. The results imply that the measurement range of the developed multichannel analyzer can be extended to the nonlinear absorption region. The measurement range and accuracy are evaluated through experimental laboratory calibration. Excellent agreement was achieved, with a Pearson correlation coefficient (r2) of 0.99977 with a measurement range from approximately 5 to 10 000 ppmv and a measurement error of less than 2 %. The instrument was also deployed for field measurement. Emissions from three different factories were measured. The emissions of these factories have been characterized by different coexisting infrared absorbers, covering a wide range of concentration levels. We compared our measurements with commercial SO2 analyzers. Overall, good agreement was achieved.

  5. VOC SURVEILLANCE USING EPA'S TRACE ATMOSPHERIC GAS ANALYZER (TAGA) AND ASPECT AERIAL PLATFORM FTIR

    EPA Science Inventory

    In a heavily industrialized area in Southeast Texas, EPA atmospheric scientists recently conducted an inter-comparison study of the EPA mobile Trace Atmospheric Gas Analyzer (TAGA) and the ASPECT Aerial Platform FTIR. The TAGA is a mobile air sampling device that is capable of d...

  6. Development and Remodeling of the Vertebrate Blood-Gas Barrier

    PubMed Central

    Makanya, Andrew; Anagnostopoulou, Aikaterini; Djonov, Valentin

    2013-01-01

    During vertebrate development, the lung inaugurates as an endodermal bud from the primitive foregut. Dichotomous subdivision of the bud results in arborizing airways that form the prospective gas exchanging chambers, where a thin blood-gas barrier (BGB) is established. In the mammalian lung, this proceeds through conversion of type II cells to type I cells, thinning, and elongation of the cells as well as extrusion of the lamellar bodies. Subsequent diminution of interstitial tissue and apposition of capillaries to the alveolar epithelium establish a thin BGB. In the noncompliant avian lung, attenuation proceeds through cell-cutting processes that result in remarkable thinning of the epithelial layer. A host of morphoregulatory molecules, including transcription factors such as Nkx2.1, GATA, HNF-3, and WNT5a; signaling molecules including FGF, BMP-4, Shh, and TFG-β and extracellular proteins and their receptors have been implicated. During normal physiological function, the BGB may be remodeled in response to alterations in transmural pressures in both blood capillaries and airspaces. Such changes are mitigated through rapid expression of the relevant genes for extracellular matrix proteins and growth factors. While an appreciable amount of information regarding molecular control has been documented in the mammalian lung, very little is available on the avian lung. PMID:23484070

  7. Blood lead levels of wild Steller's eiders (Polysticta stelleri) and black scoters (Melanitta nigra) in Alaska using a portable blood lead analyzer

    USGS Publications Warehouse

    Brown, C.S.; Luebbert, J.; Mulcahy, D.; Schamber, J.; Rosenberg, D.H.

    2006-01-01

    Sea duck populations are declining in Alaska. The reasons for the decline are not known; environmental lead exposure is one suspected cause. Thirty wild Steller's eider ducks (Polysticta stelleri) and 40 wild black scoter ducks (Melanitta nigra) were tested for blood lead levels using a portable blood lead analyzer (LeadCare; ESA, Inc., Chelmsford, Massachusetts 01824, USA). Sixty-seven and one-tenth percent of the sea ducks had undetectable blood lead levels, 30.0% had values indicating normal or background lead exposure, and 2.9% had values indicating lead exposure. None of the birds had values indicating lead toxicity, and no birds demonstrated clinical signs of toxicity. Birds in areas with higher human population density had higher blood lead levels than those in less densely populated areas. This is the first time a portable blood lead analyzer has been utilized with sea ducks in a field setting. Because it provides immediate results, it is valuable as a screening tool for investigators carrying out surgical procedures on birds in the field as well as establishing baseline blood lead data on sea ducks. Lead exposure does occur in wild sea ducks, and the study indicates that additional research is needed in order to determine the role environmental lead plays in declining sea duck populations. Copyright 2006 by American Association of Zoo Veterinarians.

  8. Integrated gas analyzer for complete monitoring of turbine engine test cells.

    PubMed

    Markham, James R; Bush, Patrick M; Bonzani, Peter J; Scire, James J; Zaccardi, Vincent A; Jalbert, Paul A; Bryant, M Denise; Gardner, Donald G

    2004-01-01

    Fourier transform infrared (FT-IR) spectroscopy is proving to be reliable and economical for the quantification of many gas-phase species during testing and development of gas turbine engines in ground-based facilities such as sea-level test cells and altitude test cells. FT-IR measurement applications include engine-generated exhaust gases, facility air provided as input to engines, and ambient air in and around test cells. Potentially, the traditionally used assembly of many gas-specific single gas analyzers will be eliminated. However, the quest for a single instrument capable of complete gas-phase monitoring at turbine engine test cells has previously suffered since the FT-IR method cannot measure infrared-inactive oxygen molecules, a key operational gas to both air-breathing propulsion systems and test cell personnel. To further the quest, the FT-IR sensor used for the measurements presented in this article was modified by integration of a miniature, solid-state electrochemical oxygen sensor. Embedded in the FT-IR unit at a location near the long-effective-optical-path-length gas sampling cell, the amperometric oxygen sensor provides simultaneous, complementary information to the wealth of spectroscopic data provided by the FT-IR method. PMID:14727730

  9. Membrane mediated development of the vertebrate blood-gas-barrier.

    PubMed

    Makanya, Andrew N

    2016-03-01

    During embryonic lung development, establishment of the gas-exchanging units is guided by epithelial tubes lined by columnar cells. Ultimately, a thin blood-gas barrier (BGB) is established and forms the interface for efficient gas exchange. This thin BGB is achieved through processes, which entail lowering of tight junctions, stretching, and thinning in mammals. In birds the processes are termed peremerecytosis, if they involve cell squeezing and constriction, or secarecytosis, if they entail cutting cells to size. In peremerecytosis, cells constrict at a point below the protruding apical part, resulting in fusion of the opposing membranes and discharge of the aposome, or the cell may be squeezed by the more endowed cognate neighbors. Secarecytosis may entail formation of double membranes below the aposome, subsequent unzipping and discharge of the aposome, or vesicles form below the aposome, fuse in a bilateral manner, and release the aposome. These processes occur within limited developmental windows, and are mediated through cell membranes that appear to be of intracellular in origin. In addition, basement membranes (BM) play pivotal roles in differentiation of the epithelial and endothelial layers of the BGB. Laminins found in the BM are particularly important in the signaling pathways that result in formation of squamous pneumocytes and pulmonary capillaries, the two major components of the BGB. Some information exists on the contribution by BM to BGB formation, but little is known regarding the molecules that drive peremerecytosis, or even the origins and composition of the double and vesicular membranes involved in secarecytosis. PMID:26991887

  10. Effects of SO2 and pH on blood-gas partition coefficients of inert gases.

    PubMed

    Yamaguchi, K; Mori, M; Kawai, A; Asano, K; Takasugi, T; Umeda, A; Yokoyama, T

    1990-01-01

    Potential effects of SO2 and of pH on blood-gas partition coefficients, lambda, for inert gases, including SF6, ethane, cyclopropane, halothane, diethyl ether, acetone and N2, were systematically investigated using human blood. Measurements on lambda were performed at 37 degrees C in conditions of varied SO2 and pH using gas chromatography. Incorporating the experimental data on lambda, multiple inert gas elimination was applied to 18 patients with varied chronic lung diseases, in order to estimate the effects of SO2 and of pH on both inert gas exchange and resultant recovery of VA/Q distribution in the lung. For this purpose, the data obtained by the procedure of multiple inert gas elimination were analyzed with the classical approach but allowance was made for lambda of the indicator gas to vary according to exchange of O2 and of CO2 in the pulmonary capillary. Among the gases studied, ethane, cyclopropane, halothane and diethyl ether showed significantly smaller lambda values in the oxygenated blood than in deoxygenated blood, whereas SF6, acetone and N2 were little dependent on SO2. An increase in lambda was found for ethane and a decrease for halothane with increasing pH in the blood. The other gases were not significantly influenced by pH. In spite of these experimental findings, regional difference of either SO2 or pH in the lung did not exert important influence on the inert gas exchange or on the predicted VA/Q distribution. In conclusion, blood-gas partition coefficients of some inert gases are consistently altered by SO2 and pH, but their possible effects on inert gas exchange seem to be negligible. PMID:1965757

  11. Leptin Integrates Vertebrate Evolution: from Oxygen to the Blood-Gas Barrier

    PubMed Central

    Torday, J.S.; Powell, F.L.; Farmer, C.G.; Orgeig, S.; Nielsen, H.C.; Hall, A.J.

    2014-01-01

    The following are the proceedings of a symposium held at the Second International Congress for Respiratory Science in Bad Honnef, Germany. The goals of the symposium were to delineate the blood-gas barrier phenotype across vertebrate species; to delineate the interrelationship between the evolution of the blood-gas barrier, locomotion and metabolism; to introduce the selection pressures for the evolution of the surfactant system as a key to understanding the physiology of the blood-gas barrier; to introduce the lung lipofibroblast and its product, leptin, which coordinately regulates pulmonary surfactant, type IV collagen in the basement membrane and host defense, as the cell-molecular site of selection pressure for the blood-gas barrier; to drill down to the gene regulatory network(s) involved in leptin signaling and the blood-gas barrier phenotype; to extend the relationship between leptin and the blood-gas-barrier to diving mammals. PMID:20096383

  12. An experimental setup with ultrasonic gas analyzers and real time analysis of the composition of a binary gas mixture

    NASA Astrophysics Data System (ADS)

    Vacek, V.; Vítek, M.; Doubek, M.

    2013-04-01

    This paper describes an automated measuring apparatus with an ultrasonic gas analyzer and realtime analysis of the composition of the gas. The apparatus is designed for preparing binary gas mixtures and making measurements in a wide range of pressures (from 0.8 bara to 15 bara) and temperatures (between -15°C and 80°C). The apparatus was developed to determine the thermophysical properties of fluorocarbon mixtures for potential use in the cooling circuits of several Large Hadron Collider projects at CERN. The design of its control system took into account the safety and reliability o the gas analyzer, and the need to limit the presence of laboratory personnel. The control system was implemented in PVSS-II, the Supervisory, Control and Data Acquisition standard chosen for LHC and its experiments at CERN. The second part of the paper describes the implementation and verification of the algorithm for continuous real-time determination of the composition of the refrigerant mixture. The algorithm is based on minimizing the quadratic norm fromthe measured data and from the pre-generated look-up tables acquired from the NIST REFPROP software package.

  13. 20 CFR Appendix C to Part 718 - Blood-Gas Tables

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... (2) For arterial blood-gas studies performed at test sites 3,000 to 5,999 feet above sea level... arterial blood-gas studies performed at test sites 6,000 feet or more above sea level: Arterial PCO2 (mm Hg... tables are met: (1) For arterial blood-gas studies performed at test sites up to 2,999 feet above...

  14. [Bronchodilator aerosol propellant interferes with an photoacoustic spectrophotometer respiratory gas analyzer].

    PubMed

    Makino, A; Morimoto, Y; Matsumoto, S; Oka, H; Shimizu, K; Miyauchi, Y

    1998-05-01

    A patient with bronchial asthma was scheduled for an operation under nitrous oxide-isoflurane anesthesia. We monitored isoflurane concentrations continuously using an anesthetic gas analyzer (BK 1304). Upon puffing procaterol hydrochloride aerosol for 4 times, the analyzer showed a rapid increase in end-tidal isoflurane concentration. The BK 1304 uses infrared photoacoustic spectrophotometry and it is susceptible to interferences caused by Freon propellants in bronchodilator aerosols. We should take care in monitoring inhalational anesthetics when using aerosols containing Freon propellants. PMID:9621676

  15. Blood gas and hematological changes in experimental peracute porcine pleuropneumonia.

    PubMed Central

    Kiorpes, A L; MacWilliams, P S; Schenkman, D I; Bäckström, L R

    1990-01-01

    The effect of experimental, peracute, porcine pleuropneumonia on arterial blood gases, acid base status, the leukogram, and gross and microscopic lung structure was studied in nine growing pigs (mean weight +/- SD 10.6 +/- 2.0 kg). Pigs were inoculated intranasally with a virulent serotype 5 isolate of Actinobacillus pleuropneumoniae, and all showed signs typical of the disease within four hours. Death occurred in all pigs from 4.5 to 32 hours postinoculation (mean 14 hours). Gross and microscopic changes were typical of porcine pleuropneumonia in all pigs. Changes in the leukogram included a rapid decline in total white cells, segmented neutrophils, lymphocytes, monocytes, and eosinophils. Pigs maintained alveolar ventilation throughout the study as arterial CO2 tension was unchanged; however, arterial O2 tension and pH decreased from (mean +/- SD) 95.2 +/- 5.7 torr and 7.463 +/- 0.018 at baseline to 62.1 +/- 12.3 torr and 7.388 +/- 0.045, respectively, within 90 minutes prior to death. The data showed that in this model of peracute porcine pleuropneumonia, progressive ventilatory failure was not a feature of the disease, and the blood gas values and acid base status were maintained within physiological ranges. The histopathological hematological and physiological findings were consistent with the hypothesis that peracute porcine pleuropneumonia resembles septic shock. Images Fig. 2. Fig. 3. PMID:2106382

  16. Transcutaneous analyte measuring method (TAMM): a reflective, noninvasive, near-infrared blood chemistry analyzer

    NASA Astrophysics Data System (ADS)

    Schlager, Kenneth J.; Ruchti, Timothy L.

    1995-04-01

    TAMM for Transcutaneous Analyte Measuring Method is a near infrared spectroscopic technique for the noninvasive measurement of human blood chemistry. A near infrared indium gallium arsenide (InGaAs) photodiode array spectrometer has been developed and tested on over 1,000 patients as a part of an SBIR program sponsored by the Naval Medical Research and Development Command. Nine (9) blood analytes have been measured and evaluated during pre-clinical testing: sodium, chloride, calcium, potassium, bicarbonate, BUN, glucose, hematocrit and hemoglobin. A reflective rather than a transmissive invasive approach to measurement has been taken to avoid variations resulting from skin color and sensor positioning. The current status of the instrumentation, neural network pattern recognition algorithms and test results will be discussed.

  17. Sensor-based analyzer for continuous emission monitoring in gas pipeline applications

    SciTech Connect

    Schubert, P.F.; Sheridan, D.R.; Cooper, M.D.; Banchieri, A.J.

    1998-04-01

    Continuous emissions monitoring of gas turbine engines in pipeline service have typically been monitored using either laboratory derived instruments (CEMS), or predicted using data from low cost sensors on the engines and algorithms generated by mapping engine performance (PEMS). A new cost-effective system developed under a program sponsored by the Gas Research Institute (Chicago) combines the advantages of both systems to monitor engine emissions in gas transmission service. This hybrid system is a sensor-based analyzer that uses a sensor array, including a newly developed NO{sub x} sensor, to directly monitor NO{sub x}, CO, and O{sub 2} emissions at the stack. The gases are measured hot and wet. The new systems were installed and tested on a gas-fired Rolls Royce Spey turbine engine and on Ingersoll-Rand KVG-410 and Cooper GMVH-10 reciprocating engines in gas transmission service. These systems passed the Relative Accuracy Test (Part B) required under US EPA regulations (40 CFR 60).

  18. Crowdsourcing Malaria Parasite Quantification: An Online Game for Analyzing Images of Infected Thick Blood Smears

    PubMed Central

    Arranz, Asier; Frean, John

    2012-01-01

    Background There are 600,000 new malaria cases daily worldwide. The gold standard for estimating the parasite burden and the corresponding severity of the disease consists in manually counting the number of parasites in blood smears through a microscope, a process that can take more than 20 minutes of an expert microscopist’s time. Objective This research tests the feasibility of a crowdsourced approach to malaria image analysis. In particular, we investigated whether anonymous volunteers with no prior experience would be able to count malaria parasites in digitized images of thick blood smears by playing a Web-based game. Methods The experimental system consisted of a Web-based game where online volunteers were tasked with detecting parasites in digitized blood sample images coupled with a decision algorithm that combined the analyses from several players to produce an improved collective detection outcome. Data were collected through the MalariaSpot website. Random images of thick blood films containing Plasmodium falciparum at medium to low parasitemias, acquired by conventional optical microscopy, were presented to players. In the game, players had to find and tag as many parasites as possible in 1 minute. In the event that players found all the parasites present in the image, they were presented with a new image. In order to combine the choices of different players into a single crowd decision, we implemented an image processing pipeline and a quorum algorithm that judged a parasite tagged when a group of players agreed on its position. Results Over 1 month, anonymous players from 95 countries played more than 12,000 games and generated a database of more than 270,000 clicks on the test images. Results revealed that combining 22 games from nonexpert players achieved a parasite counting accuracy higher than 99%. This performance could be obtained also by combining 13 games from players trained for 1 minute. Exhaustive computations measured the parasite

  19. Differential Scanning Calorimetry and Evolved Gas Analysis at Mars Ambient Conditions Using the Thermal Evolved Gas Analyzer (TEGA)

    NASA Technical Reports Server (NTRS)

    Musselwhite, D. S.; Boynton, W. V.; Ming, Douglas W.; Quadlander, G.; Kerry, K. E.; Bode, R. C.; Bailey, S. H.; Ward, M. G.; Pathare, A. V.; Lorenz, R. D.

    2000-01-01

    Differential Scanning Calorimetry (DSC) combined with evolved gas analysis (EGA) is a well developed technique for the analysis of a wide variety of sample types with broad application in material and soil sciences. However, the use of the technique for samples under conditions of pressure and temperature as found on other planets is one of current C development and cutting edge research. The Thermal Evolved Gas Analyzer (MGA), which was designed, built and tested at the University of Arizona's Lunar and Planetary Lab (LPL), utilizes DSC/EGA. TEGA, which was sent to Mars on the ill-fated Mars Polar Lander, was to be the first application of DSC/EGA on the surface of Mars as well as the first direct measurement of the volatile-bearing mineralogy in martian soil.

  20. Evaluation of Portable Multi-Gas Analyzers for use by Safety Personnel

    NASA Technical Reports Server (NTRS)

    Lueck, D. E.; Meneghelli, B. J.; Bardel, D. N.

    1998-01-01

    During confined space entry operations as well as Shuttle-safing operations, United Space Alliance (USA)/National Aeronautics and Space Administration (NASA) safety personnel use a variety of portable instrumentation to monitor for hazardous levels of compounds such as nitrogen dioxide (N%), monomethylhydrazine (NMM), FREON 21, ammonia (NH3), oxygen (O2), and combustibles (as hydrogen (H2)). Except for O2 and H2, each compound is monitored using a single analyzer. In many cases these analyzers are 5 to 10 years old and require frequent maintenance. In addition, they are cumbersome to carry and tend to make the job of personnel monitoring physically taxing. As part of an effort to upgrade the sensor technology background information was requested from a total of 27 manufacturers of portable multi-gas instruments. A set of criteria was established to determine which vendors would be selected for laboratory evaluation. These criteria were based on requests made by USA/NASA Safety personnel in order to meet requirements within their respective areas for confined-space and Shuttle-safing operations. Each of the 27 manufacturers of multi-gas analyzers was sent a copy of the criteria and asked to fill in the appropriate information pertaining to their instrumentation. Based on the results of the sensor criteria worksheets, a total of 9 vendors out of 27 surveyed manufacturers were chosen for evaluation. Each vendor included in the final evaluation process was requested to configure each of two analyzers with NO2, NH3, O2, and combustible sensors. A set of lab tests was designed in order to determine which of the multi-gas instruments under evaluation was best suited for use in both shuttle and confined space operations. These tests included linearity/repeatability, zero/span drift response/recovery, humidity, interference, and maintenance. At the conclusion of lab testing three vendors were selected for additional field testing. Based on the results of both the lab and

  1. LOW COST METHODOLOGIES TO ANALYZE AND CORRECT ABNORMAL PRODUCTION DECLINE IN STRIPPER GAS WELLS

    SciTech Connect

    Jerry James; Gene Huck; Tim Knobloch

    2001-10-01

    A study group of 376 Clinton Sand wells in Ohio provided data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the causes of the abnormal production decline. Analysis of the historic frequency of the problem indicates over 70% of the wells experienced abnormal production decline. The most frequently occurring causes of abnormal production declines were determined to be fluid accumulation (46%), gas gathering restrictions (24%), and mechanical failures (23%). Data collection forms and decision trees were developed to cost-effectively diagnose the abnormal production declines and suggest corrective action. The decision trees and data collection sheets were incorporated into a procedure guide to provide stripper gas well operators with a methodology to analyze and correct abnormal production declines. The systematic methodologies and techniques developed should increase the efficiency of problem well assessment and implementation of solutions for stripper gas wells. This eight quarterly technical progress report provides a summary of the deliverables completed to date, including the results of the remediations, the procedure guide, and the technology transfer. Due to the successful results of the study to date and the efficiency of the methodology development, two to three additional wells will be selected for remediation for inclusion into the study. The results of the additional remediations will be included in the final report.

  2. LOW COST METHODOLOGIES TO ANALYZE AND CORRECT ABNORMAL PRODUCTION DECLINE IN STRIPPER GAS WELLS

    SciTech Connect

    Jerry James; Gene Huck; Tim Knobloch

    2001-12-01

    A study group of 376 Clinton Sand wells in Ohio provided data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the causes of the abnormal production decline. Analysis of the historic frequency of the problem indicates over 70% of the wells experienced abnormal production decline. The most frequently occurring causes of abnormal production declines were determined to be fluid accumulation (46%), gas gathering restrictions (24%), and mechanical failures (23%). Data collection forms and decision trees were developed to cost-effectively diagnose the abnormal production declines and suggest corrective action. The decision trees and data collection sheets were incorporated into a procedure guide to provide stripper gas well operators with a methodology to analyze and correct abnormal production declines. The systematic methodologies and techniques developed should increase the efficiency of problem well assessment and implementation of solutions for stripper gas wells. This final technical progress report provides a summary of the deliverables completed to date, including the results of the remediations, the procedure guide, and the technology transfer. Due to the successful results of the study to date and the efficiency of the methodology development, two additional wells were selected for remediation and included into the study. Furthermore, the remediation results of wells that were a part of the study group of wells are also described.

  3. Evaluation of low cost residual gas analyzers for ultrahigh vacuum applications

    SciTech Connect

    M. Rao; D. Dong

    1996-10-01

    In recent years several low cost computer controlled residual gas analyzers (RGAs) have been introduced into the market place. It would be very useful to know the performance characteristics of these RGAs in order to make an informed selection for UHV applications. The UHV applications include extreme sensitivity helium leak detection and monitoring of the residual gas spectra in UHV systems. In this article, the sensitivity and linearity data for nitrogen, hydrogen, and helium are presented in the pressure range 10{sup {minus}8}---10{sup {minus}1} Pa. Further, the relationships between focus voltage and ion currents, relative sensitivity, and fragmentation factor are also included. A direct comparison method is used in obtaining this data. Spinning rotor and extractor gauges are the transfer standard gauges used in Jefferson Lab's vacuum calibration facility, with which all the reported measurements here were carried out.

  4. Method for analyzing the gas jet impinging on a liquid surface

    NASA Astrophysics Data System (ADS)

    Mordasov, M. M.; Savenkov, A. P.; Chechetov, K. E.

    2016-05-01

    The impingement of a gas jet on a liquid surface in the stable-state regime is analyzed theoretically. We consider the case of the perpendicular jet action. It is found that for describing analytically the processes occurring in this case, it is necessary to employ the balance equation for forces at the interface and not the balance equation for pressures at the lowest point of cavity, which was used in most available publications. Recommendations for experimental studies of a gas jet impinging on a liquid surface are formulated. We report on the results of experiments confirming the correctness of our theoretical analysis and making it possible to determine the empirical value of the shape factor. The experiments were carried out with air and epoxy resin. The cavity formed on the liquid surface had radius R 0 = 1-8 mm and depth h = 0.2-12.5 mm.

  5. Enabling Continuous, Field-Based Isotope and Greenhouse Gas Measurements with WS-CRDS-based Analyzers

    NASA Astrophysics Data System (ADS)

    Rella, C.; van Pelt, A.

    2009-04-01

    When new instrumentation becomes widely available, it has the power to fundamentally change how measurements are made. In particular, technology developments that enable measurements to be done more simply, at lower cost, by a greater number of scientists, moving information-rich, laboratory-quality measurements from the lab out into the field -- these are the innovations that can aid in moving the science forward. Here we describe how the application of a novel cavity-enhanced spectroscopic technique called wavelength scanned cavity ring down spectroscopy (WS-CRDS) has been pivotal in developing gas an isotope analyzers capable of being deployed in the field, unattended, for long periods of time. This particular implementation of the traditional cavity ring down technique employs several additional key aspects of control and design to achieve highly sensitive, highly stable measurements. WS-CRDS owes its high sensitivity to an extremely long optical interaction pathlengh, as well as to its complete immunity to laser noise since the laser is actually off during the measurement. To stabilize the spectroscopic line itself, the temperature and pressure of the gas are tightly controlled. The analyzer's optical cavity, gas handling system and analog electronics are themselves also tightly temperature controlled. The heart of the WS-CRDS technique is, however, the wavelength monitor which further ensures the stability of the measurement by continuously measuring and tightly controlling the laser wavelength. A key design aspect of the WS-CRDS analyzer is its three-mirror, traveling-wave cavity which allows optical backreflections to be avoided and further adds to the inherent stability of the optical train. The analyzer owes its ease of use to the design requirement that it be field-deployable, in locations without personnel, with the ability to restart itself and automatically resume collecting data even after a power failure. Beyond the design aspects of the analyzer

  6. 20 CFR Appendix C to Part 718 - Blood-Gas Tables

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 4 2014-04-01 2014-04-01 false Blood-Gas Tables C Appendix C to Part 718... DUE TO PNEUMOCONIOSIS Pt. 718, App. C Appendix C to Part 718—Blood-Gas Tables The following tables set... rebutting evidence, if the values specified in one of the following tables are met: (1) For arterial...

  7. LOW COST METHODOLOGIES TO ANALYZE AND CORRECT ABNORMAL PRODUCTION DECLINE IN STRIPPER GAS WELLS

    SciTech Connect

    Jerry James; Gene Huck; Tim Knobloch

    2001-07-01

    The goal of this research program is to develop and deliver a procedure guide of low cost methodologies to analyze and correct problems with stripper wells experiencing abnormal production declines. A study group of wells will provide data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the historic frequency of the causes of the production problems. Once the most frequently occurring causes of the production problems are determined, data collection forms and decision trees will be designed to cost-effectively diagnose these problems and suggest corrective action. Finally, economic techniques to solve the most frequently occurring problems will be researched and implemented. These systematic methodologies and techniques will increase the efficiency of problem assessment and implementation of solutions for stripper gas wells. This seventh quarterly technical progress report further describes the data reduction and methodology to develop diagnostic tools to evaluate the cause of declines in problem wells, specifically addressing the methodology to analyze the group of wells where recent problems have occurred utilizing the data gathering forms. This report also describes the methodology to select the two wells with the greatest potential for increase and also having the most frequently occurring problem. Finally, this report describes the preliminary results of the remediation applied to the two wells selected. Two wells selected and analyzed from a twenty-four well study group indicated that their current abnormal production decline was attributable to fluid build-up in the wellbore. Subsequent remediation work of putting both wells on pump to reduce fluid build-up in the well bore decreased the flowing bottom hole pressure and increased gas production dramatically.

  8. Regolith Evolved Gas Analyzer (REGA): An Instrument to Characterize the Martian Soil Mineralogy and Atmosphere Composition

    NASA Technical Reports Server (NTRS)

    Hoffman, John H.; McKay, David S.; Ming, Douglas; Allen, Carlton C.; Hedgecock, Jud; Nienaber, Terry

    2000-01-01

    This abstract describes an instrument and experiment to be proposed for a future Mars surface mission to conduct basic research on environmental characterization. The Regolith Evolved Gas Analyzer (REGA) experiment is designed to provide information on Mars surface material properties in preparation for human missions of exploration. The goals of the investigation are: 1) Define and determine surface mineralogy of soil and dust and their effects on humans and machines; and 2) Conduct in-situ investigations aimed at identifying possible evidence of past or present life on Mars.

  9. Cannabichromene and tetrahydrocannabinol determination in mouse blood and brain by gas chromatography-mass spectrometry.

    PubMed

    DeLong, Gerald T; Wolf, Carl E; Poklis, Alphonse; Lichtman, Aron

    2011-09-01

    Cannabichromene (CBC) is a phytocannabinoid, the second most abundant cannabinoid quantitatively in marijuana. CBC has been shown to produce antinociception and anti-inflammatory effects in rodents. This method is validated for the measurement of THC and CBC simultaneously after extraction from mouse blood or brain. Whole brain harvested from mice was homogenized 2:1 (v/w) with normal saline. Fifty nanograms of THC-d₃ was added to 0.5 mL of heparinized mouse blood, brain homogenate, and THC and CBC fortified blood or brain calibrators, then equilibrated overnight at 5 °C. Two milliliters of "ice cold" acetonitrile was added drop-wise while the sample was vortex mixed, and then the sample was centrifuged and stored overnight at -30 °C. The cannabinoids were extracted from the acetonitrile layer with 2 mL of 0.2 N NaOH and 4 mL of hexane/ethyl acetate (9:1). The solvent was isolated and evaporated to dryness. Trimethylsilyl derivatives were prepared and then analyzed by gas chromatography-mass spectrometry. Linearity in blood and brain of THC and CBC was 2-10,000 ng/mL (ng/g). THC and CBC recovery ranged from 56 to 78% in blood and brain. Precision was demonstrated at 100 ng/mL and 1000 ng/mL with CVs < 15%. The validated method allows for blood and brain concentrations of cannabinoids to be quantificated and correlated with pharmacological effects produced in mice. PMID:21871159

  10. 40 CFR 1065.308 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers not...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.308 Continuous... adjusted to account for the dilution from ambient air drawn into the probe. We recommend you use the final... gases diluted in air. You may use a multi-gas span gas, such as NO-CO-CO2-C3H8-CH4, to verify...

  11. Final Scientific/Technical Report. A closed path methane and water vapor gas analyzer

    SciTech Connect

    Xu, Liukang; McDermitt, Dayle; Anderson, Tyler; Riensche, Brad; Komissarov, Anatoly; Howe, Julie

    2012-02-01

    Robust, economical, low-power and reliable closed-path methane (CH4), carbon dioxide (CO2), and water vapor (H2O) analyzers suitable for long-term measurements are not readily available commercially. Such analyzers are essential for quantifying the amount of CH4 and CO2 released from various ecosystems (wetlands, rice paddies, forests, etc.) and other surface contexts (e.g. landfills, animal husbandry lots, etc.), and for understanding the dynamics of the atmospheric CH4 and CO2 budget and their impact on climate change and global warming. The purpose of this project is to develop a closed-path methane, carbon dioxide gas and water vapor analyzer capable of long-term measurements in remote areas for global climate change and environmental research. The analyzer will be capable of being deployed over a wide range of ecosystems to understand methane and carbon dioxide exchange between the atmosphere and the surface. Measurements of methane and carbon dioxide exchange need to be made all year-round with limited maintenance requirements. During this Phase II effort, we successfully completed the design of the electronics, optical bench, trace gas detection method and mechanical infrastructure. We are using the technologies of two vertical cavity surface emitting lasers, a multiple-pass Herriott optical cell, wavelength modulation spectroscopy and direct absorption to measure methane, carbon dioxide, and water vapor. We also have designed the instrument application software, Field Programmable Gate Array (FPGA), along with partial completion of the embedded software. The optical bench has been tested in a lab setting with very good results. Major sources of optical noise have been identified and through design, the optical noise floor is approaching -60dB. Both laser modules can be temperature controlled to help maximize the stability of the analyzer. Additionally, a piezo electric transducer has been

  12. LOW COST METHODOLOGIES TO ANALYZE AND CORRECT ABNORMAL PRODUCTION DECLINE IN STRIPPER GAS WELLS

    SciTech Connect

    Jerry James; Gene Huck; Tim Knobloch

    2000-10-01

    The goal of this research program is to develop and deliver a procedure guide of low cost methodologies to analyze and correct problems with stripper wells experiencing abnormal production declines. A study group of wells will provide data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the historic frequency of the causes of the production problems. Once the most frequently occurring causes of the production problems are determined, data collection forms and decision trees will be designed to cost-effectively diagnose these problems and suggest corrective action. Finally, economic techniques to solve the most frequently occurring problems will be researched and implemented. These systematic methodologies and techniques will increase the efficiency of problem assessment and implementation of solutions for stripper gas wells. According to the original proposal, this fourth quarterly technical report was to deliver a procedure guide, a summary report, and a Society of Petroleum Engineers technical paper. However, James Engineering, Inc. was granted a six month, no cost extension to allow the required time to thoroughly investigate and prepare these portions of the study, therefore completion of the current deliverables has been re-scheduled. James Engineering, Inc. did present preliminary results of the study during a panel discussion on Stripper Gas Wells at the Society of Petroleum Engineers' Eastern Regional Meeting held in Morgantown, West Virginia October 19, 2000. No cost to the study was incurred for the preliminary presentation.

  13. Extremely sensitive CWA analyzer based on a novel optical pressure sensor in photoacoustic gas analysis

    NASA Astrophysics Data System (ADS)

    Kauppinen, Jyrki K.; Koskinen, Vesa; Uotila, Juho; Kauppinen, Ismo K.

    2004-12-01

    Major improvement into the sensitivity of broadband Fourier transform infrared (FTIR) spectrometers, used in gas analysis, can be achieved by a photoacoustic detection system, which bases on a recently introduced optical pressure sensor. The sensor is a cantilever-type microphone with interferometric measurement of its free end displacement. By using a preliminary prototype of the photoacoustic gas detector, equipped with the proposed sensor and a black body radiation source, a detection limit in the sub-ppb range was obtained for e.g. methane gas. The limit, obtained in non-resonant operation mode, is very close to the best photoacoustic results achieved with powerfull laser sources and by exploiting the cell resonances. It is also orders of magnitude better than any measurement with a black body radiation source. Furthermore, the ultimate sensitivity leads on to very small detection limits also for several chemical warfare agents (CWA) e.g. sarin, tabun and mustard. The small size of the sensor and its great thermal stability enables the construction of an extremely sensitive portable CWA analyzer in the near future.

  14. bpshape wk4: a computer program that implements a physiological model for analyzing the shape of blood pressure waveforms

    NASA Technical Reports Server (NTRS)

    Ocasio, W. C.; Rigney, D. R.; Clark, K. P.; Mark, R. G.; Goldberger, A. L. (Principal Investigator)

    1993-01-01

    We describe the theory and computer implementation of a newly-derived mathematical model for analyzing the shape of blood pressure waveforms. Input to the program consists of an ECG signal, plus a single continuous channel of peripheral blood pressure, which is often obtained invasively from an indwelling catheter during intensive-care monitoring or non-invasively from a tonometer. Output from the program includes a set of parameter estimates, made for every heart beat. Parameters of the model can be interpreted in terms of the capacitance of large arteries, the capacitance of peripheral arteries, the inertance of blood flow, the peripheral resistance, and arterial pressure due to basal vascular tone. Aortic flow due to contraction of the left ventricle is represented by a forcing function in the form of a descending ramp, the area under which represents the stroke volume. Differential equations describing the model are solved by the method of Laplace transforms, permitting rapid parameter estimation by the Levenberg-Marquardt algorithm. Parameter estimates and their confidence intervals are given in six examples, which are chosen to represent a variety of pressure waveforms that are observed during intensive-care monitoring. The examples demonstrate that some of the parameters may fluctuate markedly from beat to beat. Our program will find application in projects that are intended to correlate the details of the blood pressure waveform with other physiological variables, pathological conditions, and the effects of interventions.

  15. Penile rehabilitation with a vacuum erectile device in an animal model is related to an antihypoxic mechanism: blood gas evidence.

    PubMed

    Lin, Hao-Cheng; Yang, Wen-Li; Zhang, Jun-Lan; Dai, Yu-Tian; Wang, Run

    2013-05-01

    Our previous study showed that vacuum erectile device (VED) therapy has improved erectile function in rats with bilateral cavernous nerve crush (BCNC) injuries. This study was designed to explore the mechanism of VED in penile rehabilitation by analyzing cavernous oxygen saturation (SO2) and to examine the effect of VED therapy on preventing penile shrinkage after BCNC. Thirty adult Sprague-Dawley rats were randomly assigned into three groups: group 1, sham surgery; group 2, BCNC; and group 3, BCNC+VED. Penile length and diameter were measured on a weekly basis. After 4 weeks of therapy, the penile blood was extracted by three methods for blood gas analysis (BGA): method 1, cavernous blood was aspirated at the flaccid state; method 2, cavernous blood was aspirated at the traction state; and method 3, cavernous blood was aspirated immediately after applying VED. SO2 values were tested by the blood gas analyzer. The results showed that VED therapy is effective in preventing penile shrinkage induced by BCNC (Penile shortening: BCNC group 1.9±1.1 mm; VED group 0.3±1.0 mm; P<0.01. Penile diameter reduction: BCNC group 0.28±0.14 mm; VED group 0.04±0.14 mm; P<0.01). The mean SO2±s.d. values were increased by VED application (88.25%±4.94%) compared to the flaccid (76.53%±4.16%) or traction groups (78.93%±2.56%) (P<0.05). The calculated blood constructs in the corpus cavernosum right after VED application were 62% arterial and 38% venous blood. These findings suggest that VED therapy can effectively preserve penile size in rats with BCNC injury. The beneficial effect of VED therapy is related to antihypoxia by increasing cavernous blood SO2. PMID:23564044

  16. Use of the Cell-Dyn Sapphire hematology analyzer for automated counting of blood cells in body fluids.

    PubMed

    De Smet, Dieter; Van Moer, Guy; Martens, Geert A; Nanos, Nikolaos; Smet, Lutgarde; Jochmans, Kristin; De Waele, Marc

    2010-02-01

    The enumeration and identification of blood cells in body fluids offers important information for the diagnosis and treatment of various medical conditions. Manual microscopic methods (hemacytometer total cell count and cytocentrifuged differential count) have inherent analytic and economic disadvantages but are still considered the "gold standard" methods. We evaluated the analytic and clinical performance of the Cell-Dyn Sapphire hematology analyzer (Abbott Diagnostics Division, Santa Clara, CA) for automated blood cell counting and leukocyte differential counting in cerebrospinal fluid, serous fluid (peritoneal and pleural fluid), and continuous ambulatory peritoneal dialysis fluid, and we compared the performance with the respective manual methods. In the present article, we describe its applicability for the distinct body fluids, and we highlight limitations and caveats. PMID:20093239

  17. The physiological basis of pulmonary gas exchange: implications for clinical interpretation of arterial blood gases.

    PubMed

    Wagner, Peter D

    2015-01-01

    The field of pulmonary gas exchange is mature, with the basic principles developed more than 60 years ago. Arterial blood gas measurements (tensions and concentrations of O₂ and CO₂) constitute a mainstay of clinical care to assess the degree of pulmonary gas exchange abnormality. However, the factors that dictate arterial blood gas values are often multifactorial and complex, with six different causes of hypoxaemia (inspiratory hypoxia, hypoventilation, ventilation/perfusion inequality, diffusion limitation, shunting and reduced mixed venous oxygenation) contributing variably to the arterial O₂ and CO₂ tension in any given patient. Blood gas values are then usually further affected by the body's abilities to compensate for gas exchange disturbances by three tactics (greater O₂ extraction, increasing ventilation and increasing cardiac output). This article explains the basic principles of gas exchange in health, mechanisms of altered gas exchange in disease, how the body compensates for abnormal gas exchange, and based on these principles, the tools available to interpret blood gas data and, quantitatively, to best understand the physiological state of each patient. This understanding is important because therapeutic intervention to improve abnormal gas exchange in any given patient needs to be based on the particular physiological mechanisms affecting gas exchange in that patient. PMID:25323225

  18. Fast Methane Measurements Using a Novel Laser-based Gas Analyzer

    NASA Astrophysics Data System (ADS)

    Baer, D.; Gupta, M.; Owano, T.; Provencal, R.; Ricci, K.; O'Keefe, A.

    2005-12-01

    Methane has increased significantly with human population levels. Pre-1750 ice core data indicates that pre-industrialization levels were ~700 ppbv, while current levels are ~1745 ppbv. In current budget estimates of atmospheric CH4, major contributors include both natural (wetlands) and anthropogenic sources (energy, landfills, ruminants, biomass burning, rice agriculture). The strengths of these sources vary spatially and temporally. Estimates of emissions from wetlands are also uncertain due to the extreme variability of these ecosystems. Because methane lifetime is relatively long (8.4 years), atmospheric variations in concentration are small and accuracy in measurement is important for understanding spatial and temporal variability. We report on the application and independent performance characterization of a novel gas analyzer based on cavity-enhanced laser absorption spectroscopy. The Analyzer was used for the measurements of methane in ambient air for eddy correlation flux measurements and for chamber flux measurements. The Analyzer provided continuous measurements at data rates up to 20 Hz and a replicate precision of better than 2 ppbv in a 1 second measurement time.

  19. The Thermal and Evolved Gas Analyzer (TEGA) on the 1998 Mars Polar Lander

    NASA Astrophysics Data System (ADS)

    Boynton, W. V.; Lorenz, R. D.; Bailey, S. H.; Williams, M. S.; Hamara, D. K.

    1998-01-01

    The Thermal and Evolved Gas Analyzer is an instrument in the MVACS (Mars Volatiles and Climate Surveyor) payload on the 1998 Mars Polar Lander. It is due to reach the layered terrain at around 70S latitude on Mars in December 1999. The instrument will heat soil samples acquired with a robotic arm to determine their volatile content with a differential scanning calorimeter (DSC) and an evolved gas analyzer (EGA). Instrument Objectives: The instrument aims to measure the volatile content of the martian soil at depth, specifically to determine the water and CO2 content. These greenhouse gases may be present in large quantities as ices and locked chemically in the soil, particularly at high latitudes. Understanding the martian climate history and the future resource potential of Mars requires that we measure the abundance of volatile-bearing material in the soil and the minerals with which they are associated. Secondary objectives include the identification of other minerals and the detection of oxidizing compounds in the soil. Instrument Description: The instrument comprises a set of eight thermal analyzers, each of which will be used only once. Each analyzer has two identical ovens, one for the sample and one (empty) for a reference. The DSC identifies the temperature and enthalpy of phase transitions by carefully determining the difference in the energy required to heat the reference and sample ovens at a controlled rate. The DSC digitally controls the duty cycle of the power to the ovens to maintain each of them at the programmed ramp temperature. The output of the DSC is simply the difference in power required by the two ovens. The EGA analyzes the evolved gases as the ovens are heated to provide knowledge of correlated gas release associated with the phase transitions. The correlated gas release will aid in the identification of the phase responsible for the phase transition. The EGA will determine water and CO, contents via a high-resolution tunable diode laser

  20. Assessment of a continuous blood gas monitoring system in animals during circulatory stress

    PubMed Central

    2011-01-01

    Background The study was aimed to determine the measurement accuracy of The CDI™ blood parameter monitoring system 500 (Terumo Cardiovascular Systems Corporation, Ann Arbor MI) in the real-time continuous measurement of arterial blood gases under different cardiocirculatory stress conditions Methods Inotropic stimulation (Dobutamine 2.5 and 5 μg/kg/min), vasoconstriction (Arginine-vasopressin 4, 8 and 16 IU/h), hemorrhage (-10%, -20%, -35%, and -50% of the theoretical volemia), and volume resuscitation were induced in ten swine (57.4 ± 10.7 Kg).Intermittent blood gas assessments were carried out using a routine gas analyzer at any experimental phase and compared with values obtained at the same time settings during continuous monitoring with CDI™ 500 system. The Bland-Altman analysis was employed. Results Bias and precision for pO2 were - 0.06 kPa and 0.22 kPa, respectively (r2 = 0.96); pCO2 - 0.02 kPa and 0.15 kPa, respectively; pH -0.001 and 0.01 units, respectively ( r2 = 0.96). The analysis showed very good agreement for SO2 (bias 0.04,precision 0.33, r2 = 0.95), Base excess (bias 0.04,precision 0.28, r2 = 0.98), HCO3 (bias 0.05,precision 0.62, r2 = 0.92),hemoglobin (bias 0.02,precision 0.23, r2 = 0.96) and K+ (bias 0.02, precision 0.27, r2 = 0.93). The sensor was reliable throughout the experiment during hemodynamic variations. Conclusions Continuous blood gas analysis with the CDI™ 500 system was reliable and it might represent a new useful tool to accurately and timely monitor gas exchange in critically ill patients. Nonetheless, our findings need to be confirmed by larger studies to prove its reliability in the clinical setting. PMID:21223536

  1. Determination of paraldehyde by gas chromatography in whole blood from children.

    PubMed

    Githiga, Isaiah M; Muchohi, Simon N; Ogutu, Bernhards R; Newton, Charles R J C; Otieno, Godfrey O; Gitau, Evelyn N; Kokwaro, Gilbert O

    2004-06-15

    A rapid, sensitive and selective gas chromatographic method with flame ionization detection was developed for the determination of paraldehyde in small blood samples taken from children. Whole blood samples (300 microl) collected in a 3 ml Wheaton glass sample vial were spiked with acetone (internal standard: 15 ng) followed by addition of concentrated hydrochloric acid. The mixture was heated in the sealed airtight sample vial in a water bath (96 Celsius; 5 min) to depolymerize paraldehyde to acetaldehyde. A 2 ml aliquot of the headspace was analyzed by gas chromatography with flame ionization detector using a stainless steel column (3 m x 4 mm i.d.) packed with 10% Carbowax 20 M/ 2% KOH on 80/100 Chromosorb WAW. Calibration curves were linear from 1.0-20 microg (r2>0.99). The limit of detection was 1.5 microg/ml, while relative mean recoveries at 2 and 18 microg were 105.6 +/- 8.4 and 101.2 +/- 5.9%, respectively (n = 10 for each level). Intra- and inter-assay relative standard deviations at 2, 10 and 18 microg were <15%. There was no interference from other drugs concurrently used in children with severe malaria, such as anticonvulsants (diazepam, phenytoin, phenobarbitone), antipyretics/analgesics (paracetamol and salicylate), antibiotics (gentamicin, chloramphenicol, benzyl penicillin) and antimalarials (chloroquine, quinine, proguanil, cycloguanil, pyrimethamine and sulfadoxine). The method was successfully applied for pharmacokinetic studies of paraldehyde in children with convulsions associated with severe malaria. PMID:15135115

  2. Summary of Results from the Mars Phoenix Lander's Thermal Evolved Gas Analyzer

    NASA Technical Reports Server (NTRS)

    Sutter, B.; Ming, D. W.; Boynton, W. V.; Niles, P. B.; Hoffman, J.; Lauer, H. V.; Golden, D. C.

    2009-01-01

    The Mars Phoenix Scout Mission with its diverse instrument suite successfully examined several soils on the Northern plains of Mars. The Thermal and Evolved Gas Analyzer (TEGA) was employed to detect evolved volatiles and organic and inorganic materials by coupling a differential scanning calorimeter (DSC) with a magnetic-sector mass spectrometer (MS) that can detect masses in the 2 to 140 dalton range [1]. Five Martian soils were individually heated to 1000 C in the DSC ovens where evolved gases from mineral decompostion products were examined with the MS. TEGA s DSC has the capability to detect endothermic and exothermic reactions during heating that are characteristic of minerals present in the Martian soil.

  3. 40 CFR 1065.308 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers not...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.308 Continuous..., the gas concentrations must be adjusted to account for the dilution from ambient air drawn into the... recommended when blending span gases diluted in N2 with span gases diluted in air. You may use a...

  4. 40 CFR 1065.308 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers not...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.308 Continuous..., the gas concentrations must be adjusted to account for the dilution from ambient air drawn into the... recommended when blending span gases diluted in N2 with span gases diluted in air. You may use a...

  5. 40 CFR 1065.308 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers not...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.308 Continuous..., the gas concentrations must be adjusted to account for the dilution from ambient air drawn into the... recommended when blending span gases diluted in N2 with span gases diluted in air. You may use a...

  6. 40 CFR 1065.308 - Continuous gas analyzer system-response and updating-recording verification-for gas analyzers not...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications § 1065.308 Continuous..., the gas concentrations must be adjusted to account for the dilution from ambient air drawn into the... recommended when blending span gases diluted in N2 with span gases diluted in air. You may use a...

  7. LOW COST METHODOLOGIES TO ANALYZE AND CORRECT ABNORMAL PRODUCTION DECLINE IN STRIPPER GAS WELLS

    SciTech Connect

    Jerry James; Gene Huck; Tim Knobloch

    2001-01-01

    The goal of this research program is to develop and deliver a procedure guide of low cost methodologies to analyze and correct problems with stripper wells experiencing abnormal production declines. A study group of wells will provide data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the historic frequency of the cases of the production problems. Once the most frequently occurring causes of the production problems are determined, data collection forms and decision trees will be designed to cost-effectively diagnose these problems and suggest corrective action. Finally, economic techniques to solve the most frequently occurring problems will be research and implemented. These systematic methodologies and techniques will increase the efficiency of problem assessment and implementation of solutions for stripper gas wells. This fifth quarterly technical report describes the data reduction and methodology to develop diagnostic tools to evaluate the cause of declines in problem wells, specifically addressing the development of data gathering forms for tubing plunger wells, casing plunger wells, pumping wells, and swab or flow wells. This report also describes the methodology to select a group of wells for field review utilizing data gathering forms developed during this quarter.

  8. Low cost methodologies to analyze and correct abnormal production decline in stripper gas wells

    SciTech Connect

    James, J.; Huck, G.; Knobloch, T.

    2000-04-01

    The goal of this research program is to develop and deliver a procedure guide of low cost methodologies to analyze and correct problems with stripper wells experiencing abnormal production declines. A study group of wells will provide data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the historic frequency of the causes of the production problems. Once the most frequently occurring causes of the production problems are determined, data collection forms and decision trees will be designed to cost-effectively diagnose these problems and suggest corrective action. Finally, economic techniques to solve the most frequently occurring problems will be researched and implemented. These systematic methodologies and techniques will increase the efficiency of problem assessment and implementation of solutions for stripper gas wells. This second quarterly technical report describes the data reduction and methodology to develop data collection forms of pertinent information to assist in analysis of problem wells. The report also describes the procedures to categorize individual well problems. Finally, the report summarizes the frequency of individual well problems.

  9. LOW COST METHODOLOGIES TO ANALYZE AND CORRECT ABNORMAL PRODUCTION DECLINE IN STRIPPER GAS WELLS

    SciTech Connect

    Jerry James; Gene Huck; Tim Knobloch

    2001-04-01

    The goal of this research program is to develop and deliver a procedure guide of low cost methodologies to analyze and correct problems with stripper wells experiencing abnormal production declines. A study group of wells will provide data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the historic frequency of the causes of the production problems. Once the most frequently occurring causes of the production problems are determined, data collection forms and decision trees will be designed to cost-effectively diagnose these problems and suggest corrective action. Finally, economic techniques to solve the most frequently occurring problems will be researched and implemented. These systematic methodologies and techniques will increase the efficiency of problem assessment and implementation of solutions for stripper gas wells. This sixth quarter technical progress report further describes the data reduction and methodology to develop diagnostic tools to evaluate the cause of declines in problem wells, specifically addressing the development of data gathering forms for tubing plunger wells, casing plunger wells, pumping wells, and swab or flow wells. This report also further describes the methodology to select a group of wells for field review utilizing data gathering forms further developed during this quarter.

  10. Status of the design of the Diagnostic Residual Gas Analyzer System for ITER first plasma

    NASA Astrophysics Data System (ADS)

    Biewer, T. M.; Klepper, C. C.; Devan, B.; Graves, V.; Marcus, C.; Younkin, T.; Andrew, P.; Johnson, D. W.

    2013-10-01

    Among the ITER procurements awarded to the US ITER Domestic Agency, and subsequently to the ORNL Fusion & Materials for Nuclear Systems Division, is the design and fabrication of the Diagnostc Residual Gas Analyzer (DRGA) system. The DRGA system reached the Preliminary Design Review (PDR) in Spring 2013, and has transitioned into the Final Design phase. As a result of the PDR, and ITER systems design evolutions, several design changes have been incorporated into the DRGA system. The design effort has focused on the vacuum and mechanical interface of the DRGA gas sampling tube with the ITER vacuum vessel and cyrostat. Moreover, R&D tasks to demonstrate the 3-sensor instrumentation design (quadrupole mass spectrometer, ion-trap mass spectrometer, and optical Penning gauge) are maturing through the construction and testing of a DRGA prototype at ORNL. Results will be presented at this poster along with the DRGA design overview. This work was supported by the U.S. D.O.E. contract DE-AC05-00OR22725.

  11. Perchlorate induced low temperature carbonate decomposition in the Mars Phoenix Thermal and Evolved Gas Analyzer (TEGA)

    NASA Astrophysics Data System (ADS)

    Cannon, K. M.; Sutter, B.; Ming, D. W.; Boynton, W. V.; Quinn, R.

    2012-07-01

    Simulated Thermal Evolved Gas Analyzer (TEGA) analyses have shown that a CO2 release detected between 400°C and 680°C by the Phoenix Lander's TEGA instrument may have been caused by a reaction between calcium carbonate and hydrated magnesium perchlorate. In our experiments a CO2 release beginning at 385 ± 12°C was attributed to calcite reacting with water vapor and HCl gas from the dehydration and thermal decomposition of Mg-perchlorate. The release of CO2 is consistent with the TEGA detection of CO2 released between 400 and 680°C, with the amount of CO2 increasing linearly with added perchlorate. X-ray diffraction (XRD) experiments confirmed CaCl2 formation from the reaction between calcite and HCl. These results have important implications for the Mars Science Laboratory (MSL) Curiosity rover. Heating soils may cause inorganic release of CO2; therefore, detection of organic fragments, not CO2 alone, should be used as definitive evidence for organics in Martian soils.

  12. A volatile organic analyzer for Space Station: Description and evaluation of a gas chromatography/ ion mobility

    NASA Technical Reports Server (NTRS)

    Limero, Thomas F.; James, John T.

    1994-01-01

    A Volatile Organic Analyzer (VOA) is being developed as an essential component of the Space Station's Environmental Health System (EHS) air quality monitoring strategy to provide warning to the crew and ground personnel if volatile organic compounds exceed established exposure limits. The short duration of most Shuttle flights and the relative simplicity of the contaminant removal mechanism have lessened the concern about crew exposure to air contaminants on the Shuttle. However, the longer missions associated with the Space Station, the complex air revitalization system and the proposed number of experiments have led to a desire for real-time monitoring of the contaminants in the Space Station atmosphere. Achieving the performance requirements established for the VOA within the Space Station resource (e.g., power, weight) allocations led to a novel approach that joined a gas chromatograph (GC) to an ion mobility spectrometer (IMS). The authors of this paper will discuss the rational for selecting the GC/IMS technology as opposed to the more established gas chromatography/mass spectrometry (GC/MS) for the foundation of the VOA. The data presented from preliminary evaluations will demonstrate the versatile capability of the GC/IMS to analyze the major contaminants expected in the Space Station atmosphere. The favorable GC/IMS characteristics illustrated in this paper included excellent sensitivity, dual-mode operation for selective detection, and mobility drift times to distinguish co-eluting GC peaks. Preliminary studies have shown that the GC/IMS technology can meet surpass the performance requirements of the Space Station VOA.

  13. EVALUATION OF A PORTABLE FOURIER TRANSFORM INFRARED GAS ANALYZER FOR MEASUREMENTS OF AIR TOXICS IN POLLUTION PREVENTION RESEARCH

    EPA Science Inventory

    A portable Fourier transform infrared gas analyzer with a photoacoustic detector performed reliably during pollution prevention research at two industrial facilities. It exhibited good agreement (within approximately 6%) with other analytical instruments (dispersive infrared and ...

  14. Low cost methodologies to analyze and correct abnormal production decline in stripper gas wells

    SciTech Connect

    James, J.; Huck, G.; Knobloch, T.

    2000-07-01

    The goal of this research program is to develop and deliver a procedure guide of low cost methodologies to analyze and correct problems with stripper wells experiencing abnormal production declines. A study group of wells will provide data to determine the historic frequency of the problem of abnormal production declines in stripper gas wells and the historic frequency of the causes of the production problems. Once the most frequently occurring causes of the production problems are determined, data collection forms and decision trees will be designed to cost-effectively diagnose these problems and suggest corrective action. Finally, economic techniques to solve the most frequently occurring problems will be researched and implemented. These systematic methodologies and techniques will increase the efficiency of problem assessment and implementation of solutions for stripper gas wells. This third quarterly technical report was to describe the data reduction and methodologies to develop decision trees, identify cost effective techniques to solve the most frequently experienced problems and then apply the methodology to a group of wells where recent problems have developed. Further, this third quarterly technical report was to describe the data reduction and methodologies to select the two wells with the greatest potential for increase and also having the most frequently occurring problem, and evaluate the results of the methodology and the implemented procedure. However, preparation and analysis of the decision trees is more complex than initially anticipated due to the combination of problems rather than identifiable individual problems. Therefore, this portion of the study is still in progress. We have requested and been granted verbal approval for a six month no cost extension to allow more time to thoroughly investigate this portion of the study. The delivery of the decision trees will be included in future technical reports. Work on the other tasks to be

  15. Development of a Contingency Gas Analyzer for the Orion Crew Exploration Vehicle

    NASA Technical Reports Server (NTRS)

    Niu, Bill; Carney, Kenneth; Steiner, George; OHarra, William; Lewis, John

    2010-01-01

    NASA's experience with electrochemical sensors in a hand-held toxic gas monitor serves as a basis for the development of a fixed on-board instrument, the Contingency Gas Analyzer (CGA), for monitoring selected toxic combustion products as well as oxygen and carbon dioxide on the Orion Crew Exploration Vehicle (CEV). Oxygen and carbon dioxide are major components of the cabin environment and accurate measurement of these compounds is critical to maintaining a safe working environment for the crew. Fire or thermal degradation events may produce harmful levels of toxic products, including carbon monoxide (CO), hydrogen cyanide (HCN), and hydrogen chloride (HCl) in the environment. These three components, besides being toxic in their own right, can serve as surrogates for a panoply of hazardous combustion products. On orbit monitoring of these surrogates provides for crew health and safety by indicating the presence of toxic combustion products in the environment before, during and after combustion or thermal degradation events. Issues identified in previous NASA experiences mandate hardening the instrument and components to endure the mechanical and operational stresses of the CEV environment while maintaining high analytical fidelity. Specific functional challenges involve protecting the sensors from various anticipated events- such as rapid pressure changes, low cabin pressures, and extreme vibration/shock exposures- and extending the sensor lifetime and calibration periods far beyond the current state of the art to avoid the need for on-orbit calibration. This paper focuses on lessons learned from the earlier NASA hardware, current testing results, and engineering solutions to the identified problems. Of particular focus will be the means for protecting the sensors, addressing well known cross-sensitivity issues and the efficacy of a novel self monitoring mechanism for extending sensor calibration periods.

  16. Sampling Line Heating Improves Frequency Response of Enclosed Eddy Covariance Gas Analyzers

    NASA Astrophysics Data System (ADS)

    Burba, G. G.; Fratini, G.; Metzger, S.; Kathilankal, J. C.; Trutna, D.; Luo, H.; Burns, S. P.; Blanken, P.

    2015-12-01

    One of the challenges when measuring eddy-covariance fluxes with closed gas analyzers is high frequency attenuation due to the passage of the sampled air through a gas sampling system (GSS). The problem is particularly relevant for gases that undergo strong sorption processes, such as H2O. Recent "enclosed" analyzer designs (e.g. LI-7200, LI-COR Biosciences Inc.) mitigate the problem by allowing a reduced length of the intake tube (<1 m). Further improvements can come from carefully designed filtering and heating systems that reduce hygroscopic particulates and H2O adsorption on GSS surfaces. Because the sorption processes of H2O increase exponentially with air relative humidity (RH), low-pass filtering effects can be reduced by reducing RH inside the GSS, for example by increasing air temperature via heating. In this work, we evaluate the effects of several heating strategies with the aim of optimizing the LI-7200 performance while limiting the implied increase in power consumption. From field tests we found that 4 W of heating applied uniformly to a rain cap-integrated 2 µm particulate filter (FW-series, Swagelok) and a 700 mm stainless steel tube with 4.8 mm inner diameter reduces the occurrence of problematic RH levels (>60%) in the LI-7200 by ≈50%. As a result, the system half-power frequency increased by ≈1 Hz, and the remaining cospectral correction did not exceed 3%, even at very high ambient RH (95%). While little further improvement was found for increased heating powers, it is possible to optimize the sequence of GSS components and their heating: we found that positioning the particulate filter ≈20 cm downstream of the rain cap and concentrating 2/3 of the heat in this first 20 cm, and 1/3 in the remainder of the tube, provides optimal performances. Using model cospectra and a range of realistic measurement and environmental conditions, we estimated H2O spectral corrections to reduce by ≈50-70%, getting very close to those of CO2 in most

  17. Quantification of red blood cell fragmentation by the automated hematology analyzer XE-2100 in patients with living donor liver transplantation.

    PubMed

    Banno, S; Ito, Y; Tanaka, C; Hori, T; Fujimoto, K; Suzuki, T; Hashimoto, T; Ueda, R; Mizokami, M

    2005-10-01

    The fragmented red cell (FRC) is a useful index for diagnosing and determining the severity of thrombotic thrombocytopenic purpura (TTP), thrombotic microangiopathy (TMA) and other similar conditions, as it is found in peripheral blood in patients with these diseases. The FRC expression rate has conventionally been determined by manual methods using smear samples. However, it is difficult to attain accurate quantification by such methods as they are time consuming and prone to a great margin of error. With cases of living donor liver transplantation, the current study examined the possibility of using a multi-parameter automated hematology analyzer, the XE-2100 (Sysmex Corporation) for FRC quantification. While there was a notable correlation between the manual and automated measurements, the manual measurement resulted in higher values. This suggested remarkable variations in judgment by individuals. The FRC values had a significant correlation with the reticulocyte count, red blood cell distribution width (RDW), fibrin/fibrinogen degradation products (P-FDP) and lactate dehydrogenase (LDH) among the test parameters, and this finding was consistent with the clinical progression in patients. The automated method can offer precise measurements in a short time without inter-observer differences, meeting the requirement for standardization. The determination of FRC count (%) by the XE-2100 that enables early diagnoses and monitoring of TTP or TMA will be useful in the clinical field. PMID:16178907

  18. Blood

    MedlinePlus

    ... solid part of your blood contains red blood cells, white blood cells, and platelets. Red blood cells (RBC) deliver oxygen from your lungs to your tissues and organs. White blood cells (WBC) fight infection and are part of your ...

  19. A software toolkit for processing and analyzing spectral and trace gas flux data collected via aircraft

    NASA Astrophysics Data System (ADS)

    Xu, Y.; Garrity, S. R.; Vierling, L. A.; Martins, D. K.; Shepson, P. B.; Stirm, B. H.

    2006-12-01

    In order to spatially extrapolate trace gas flux measurements made at the scale of individual flux towers to broader regions using spectral approaches, it is helpful to establish new methodologies for sampling and processing these data at scales coarser than one flux tower footprint. To this end, we mounted a dual-channel hyperspectral spectroradiometer capable of collecting spectra at ~3Hz to an experimental twin-engine Beechcraft Duchess instrumented to also measure eddy covariance fluxes of CO2. Experimental flights were conducted over a northern hardwood, deciduous forest between 21 July and 24 July 2006. To analyze these data in ecologically meaningful ways, it was necessary to first develop a software toolkit capable of marrying the spectral and flux data in appropriate spatial and spectral contexts. The toolkit is capable of merging the spectral and flux data streams with the GPS/Inertial Navigation System of the aircraft such that data can be interactively selected according to its timestamp or geographic location and queried to output a variety of preset and/or user defined spectral indices for comparison to collocated flux data. In addition, the toolkit enables the user to interactively plot the spectral target locations on any georectified image to facilitate comparisons among land cover type, topography, surface spectral characteristics, and CO2 fluxes. In this paper, we highlight the capabilities of the software toolkit as well as provide examples of ways in which it can be used to explore correlation among spectral and flux data collected via aircraft.

  20. A Fast Exhaust-Gas Analyzer for the ITER Fusion Experiment Divertor

    SciTech Connect

    Klepper, C Christopher; Carlson, E. P.; Moschella, J. J.; Hazelton, R C; Keitz, M D; Gardner, Walter L

    2010-01-01

    This paper presents a first demonstration of a radio-frequency (RF)-excited optical gas analyzer (RF-OGA) designed to quantitatively measure minority species inside the neutralization region of the ITER fusion experiment divertor. The sensor head, which creates its own plasma excitation and plasma light emission, is designed to operate in a strong magnetic field, and the RF coupling leads to bright light emission. It also allows for operation at low voltages, avoiding the radiation-enhanced breakdowns expected when high voltages are present in the ITER environment. Furthermore, the preferred sensor head features full isolation of the metal RF electrodes from the induced plasma. This "electrodeless" operation will permit long operation without frequent maintenance. The testing of a first experimental RF-OGA with an electrodeless design in a strong (similar to 2-T) magnetic field showed a mostly linear response of the He I-6678 angstrom line emission to the He concentration in a hydrogen background, which would produce a He concentration measurement accurate to within 2% of the helium-to-hydrogen ratio.

  1. Analyzing the Impact of Residential Building Attributes, Demographic and Behavioral Factors on Natural Gas Usage

    SciTech Connect

    Livingston, Olga V.; Cort, Katherine A.

    2011-03-03

    study attempts to bridge that gap by analyzing behavioral data and investigate the applicability of additive nonparametric regression to this task. This study evaluates the impact of 31 regressors on residential natural gas usage. The regressors include weather, economic variables, demographic and behavioral characteristics, and building attributes related to energy use. In general, most of the regression results were in line with previous engineering and economic studies in this area. There were, however, some counterintuitive results, particularly with regard to thermostat controls and behaviors. There are a number of possible reasons for these counterintuitive results including the inability to control for regional climate variability due to the data sanitization (to prevent identification of respondents), inaccurate data caused by to self-reporting, and the fact that not all relevant behavioral variables were included in the data set, so we were not able to control for them in the study. The results of this analysis could be used as an in-sample prediction for approximating energy demand of a residential building whose characteristics are described by the regressors in this analysis, but a certain combination of their particular values does not exist in the real world. In addition, this study has potential applications for benefit-cost analysis of residential upgrades and retrofits under a fixed budget, because the results of this study contain information on how natural gas consumption might change once a particular characteristic or attribute is altered. Finally, the results of this study can help establish a relationship between natural gas consumption and changes in behavior of occupants.

  2. Gas chromatographic determination of pentachlorophenol in human blood and urine

    SciTech Connect

    Atuma, S.S.; Okor, D.I.

    1985-09-01

    The extraction, identification and quantification of pentachlorophenol (PCP) in human blood and urine are of great importance for monitoring human exposure to this environmental chemical. Although reports abound in the literature on PCP residues, toxicity and environmental fate, there is hardly any information on its existence in the developing tropical countries, particularly in Nigeria. There is therefore the need to survey the status of PCP in Nigerian environment with a view to establishing the potential health hazards resulting from its bioaccumulation. This paper reports a preliminary survey of the residue levels of PCP in human blood and urine of the general population in Bendel State of Nigeria.

  3. Determination of natural in vivo noble-gas concentrations in human blood.

    PubMed

    Tomonaga, Yama; Brennwald, Matthias S; Livingstone, David M; Tomonaga, Geneviève; Kipfer, Rolf

    2014-01-01

    Although the naturally occurring atmospheric noble gases He, Ne, Ar, Kr, and Xe possess great potential as tracers for studying gas exchange in living beings, no direct analytical technique exists for simultaneously determining the absolute concentrations of these noble gases in body fluids in vivo. In this study, using human blood as an example, the absolute concentrations of all stable atmospheric noble gases were measured simultaneously by combining and adapting two analytical methods recently developed for geochemical research purposes. The partition coefficients determined between blood and air, and between blood plasma and red blood cells, agree with values from the literature. While the noble-gas concentrations in the plasma agree rather well with the expected solubility equilibrium concentrations for air-saturated water, the red blood cells are characterized by a distinct supersaturation pattern, in which the gas excess increases in proportion to the atomic mass of the noble-gas species, indicating adsorption on to the red blood cells. This study shows that the absolute concentrations of noble gases in body fluids can be easily measured using geochemical techniques that rely only on standard materials and equipment, and for which the underlying concepts are already well established in the field of noble-gas geochemistry. PMID:24811123

  4. Determination of Natural In Vivo Noble-Gas Concentrations in Human Blood

    PubMed Central

    Tomonaga, Yama; Brennwald, Matthias S.; Livingstone, David M.; Tomonaga, Geneviève; Kipfer, Rolf

    2014-01-01

    Although the naturally occurring atmospheric noble gases He, Ne, Ar, Kr, and Xe possess great potential as tracers for studying gas exchange in living beings, no direct analytical technique exists for simultaneously determining the absolute concentrations of these noble gases in body fluids in vivo. In this study, using human blood as an example, the absolute concentrations of all stable atmospheric noble gases were measured simultaneously by combining and adapting two analytical methods recently developed for geochemical research purposes. The partition coefficients determined between blood and air, and between blood plasma and red blood cells, agree with values from the literature. While the noble-gas concentrations in the plasma agree rather well with the expected solubility equilibrium concentrations for air-saturated water, the red blood cells are characterized by a distinct supersaturation pattern, in which the gas excess increases in proportion to the atomic mass of the noble-gas species, indicating adsorption on to the red blood cells. This study shows that the absolute concentrations of noble gases in body fluids can be easily measured using geochemical techniques that rely only on standard materials and equipment, and for which the underlying concepts are already well established in the field of noble-gas geochemistry. PMID:24811123

  5. Phoenix Lander's Thermal Evolved Gas Analyzer: Differential Scanning Calorimeter and Mass Spectrometer Database Development

    NASA Technical Reports Server (NTRS)

    Sutter, B.; Lauer, H. V.; Golden, D. C.; Ming, D. W.; Boynton, W. V.

    2008-01-01

    The Mars Scout Phoenix lander will land in the north polar region of Mars in May, 2008. One objective of the Phoenix lander is to search for evidence of past life in the form of molecular organics that may be preserved in the subsurface soil. The Thermal Evolved Gas Analyzer (TEGA) was developed to detect these organics by coupling a simultaneous differential thermal analyzer (SDTA) with a mass spectrometer. Martian soil will be heated to approx.1000 C and potential organic decomposition products such as CO2, CH4 etc. will be examined for with the MS. TEGA s SDTA will also assess the presence of endothermic and exothermic reactions that are characteristic of soil organics and minerals as the soil is heated. The MS in addition to detecting organic decompositon products, will also assess the levels of soil inorganic volatiles such as H2O, SO2, and CO2. Organic detection has a high priority for this mission; however, TEGA has the ability to provide valuable insight into the mineralogical composition of the soil. The overall goal of this work is to develop a TEGA database of minerals that will serve as a reference for the interpretation of Phoenix-TEGA. Previous databases for the ill-fated Mars Polar Lander (MPL)-TEGA instrument only went to 725 C. Furthermore, the MPL-TEGA could only detect CO2 and H2O while the Phoenix-TEGA MS can examine up to 144 atomic mass units. The higher temperature Phoenix-TEGA SDTA coupled with the more capable MS indicates that a higher temperature database is required for TEGA interpretation. The overall goal of this work is to develop a differential scanning calorimeter (DSC) database of minerals along with corresponding MS data of evolved gases that can used to interpret TEGA data during and after mission operations. While SDTA and DSC measurement techniques are slightly different (SDTA does not use a reference pan), the results are fundamentally similar and thus DSC is a useful technique in providing comparative data for the TEGA

  6. Greenhouse gas source identification and flux measurements using an optical remote sensing method and a photoacoustic multi-gas analyzer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil properties such as particle size, soil organic carbon (SOC) and moisture contents, tillage operations and crop management practices influence greenhouse gas emission or consumption patterns from agricultural lands. Greenhouse gas (GG) emissions have been measured on small field plots, although ...

  7. Blood gas analysis of the coronary sinus in patients with heart failure

    PubMed Central

    ZHANG, JIANGHUA; SHAN, CHUNFANG; ZHANG, YU; ZHOU, XIANHUI; LI, JINXIN; LI, YAODONG; XING, QIANG; TANG, BAOPENG

    2015-01-01

    The difference in cardiac oxygen consumption between individuals with normal cardiac function and those with heart failure (HF), and the association between cardiac oxygen consumption and cardiac ejection fraction (EF) are poorly understood. By establishing a control group composed of individuals with normal cardiac function, the present study aimed to determine the difference in cardiac oxygen consumption between individuals with normal and abnormal cardiac function, as well as the association between cardiac oxygen consumption and cardiac EF. A total of 34 patients with normal cardiac function were enrolled in the control group and 44 patients with HF were enrolled in the experimental group. Blood samples from the aortic root, femoral vein and coronary sinus (CS) were collected from each patient. All the blood samples were subjected to blood gas analysis. The partial pressure of oxygen and oxygen saturation obtained from the peripheral vein and CS of patients with HF were lower than those in patients with normal cardiac function. In each patient with HF, the association between cardiac oxygen consumption and cardiac EF was analyzed using multi-linear correlation and regression analyses. Cardiac oxygen consumption negatively correlated with cardiac EF (R=-0.336, P=0.026). Furthermore, linear regression analysis suggested that cardiac EF had a significant effect on cardiac oxygen consumption (y = 82.906–0.483×, P=0.026). In conclusion, myocardial oxygen consumption is greater in individuals with HF compared to those with normal cardiac function. The cardiac EF affects myocardial oxygen consumption in patients with HF. PMID:26137240

  8. Genetic and phenotypic relationships between blood gas parameters and ascites-related traits in broilers.

    PubMed

    Closter, A M; van As, P; Groenen, M A M; Vereijken, A L J; van Arendonk, J A M; Bovenhuis, H

    2009-03-01

    Ascites, also called pulmonary hypertension syndrome, is a metabolic disorder in chickens that have an insufficient pulmonary vascular capacity. The tendency of broilers to develop ascites is heritable, and successful selection against this susceptibility would benefit from good and easy-to-measure indicator traits. Blood gas parameters have been suggested as indicator traits for ascites susceptibility. Therefore, the aim of the present study was to estimate the heritability of blood gas parameters and the genetic and phenotypic correlations between blood gas parameters, heart ratio (postmortem indicator for ascites), and BW at 2 different ages. For this purpose, blood gas parameters, including the partial pressure of carbon dioxide in venous blood (pvCO(2)), the partial pressure of oxygen in venous blood (pvO(2)), and blood oxygen saturation, were measured at an average age of 22 d in nearly 3,000 broilers. To challenge the resistance of the birds to ascites, they were kept under cold conditions. Heritability for heart ratio was 0.43, and the heritability estimates were low: 0.02 for pvCO(2), 0.03 for pvO(2), and 0.07 for blood oxygen saturation. The estimated heritability for pH was 0.15, for bicarbonate was 0.19, and for total carbon dioxide content was 0.19. The genetic correlations between heart ratio and total carbon dioxide content (0.31 +/- 0.15) and between heart ratio and bicarbonate (0.31 +/- 0.15) were moderate and positive. For pvO(2), the genetic correlation with heart ratio was stronger and negative (-0.62 +/- 0.21); however, this correlation could not be estimated accurately because of the low heritability of pvO(2). For pvCO(2), the genetic correlation with the heart ratio was close to zero (-0.04 +/- 0.45). Phenotypic correlations between traits were, in general, similar to the genetic correlations. Heritabilities for blood gas parameters and the genetic correlations between blood gas parameters and the heart ratio estimated in the present study

  9. Reduction in Red Blood Cell Transfusions Among Preterm Infants: Results of a Randomized Trial With an In-Line Blood Gas and Chemistry Monitor

    PubMed Central

    Widness, John A.; Madan, Ashima; Grindeanu, Ligia A.; Zimmerman, M. Bridget; Wong, David K.; Stevenson, David K.

    2010-01-01

    Background Critically ill, extremely premature infants develop anemia because of intensive laboratory blood testing and undergo multiple red blood cell (RBC) transfusions in the early weeks of life. To date, researchers have had only limited success in finding ways to reduce transfusions significantly in this patient population. Objective To reduce RBC transfusions for these infants by using a point-of-care bedside monitor that returns analyzed blood to the patient. Design, Setting, and Patients This was a prospective, 2-center, randomized, open, controlled, clinical trial with a 1:1 assignment of extremely low birth weight infants (weighing 500–1000 g at birth) to control or monitor groups and analysis with the intention-to-treat approach. Predefined RBC transfusion criteria were applied uniformly in the 2 groups. Interventions Clinical treatment of study subjects with an in-line, ex vivo, bedside monitor that withdraws blood through an umbilical artery catheter, analyzes blood gases and sodium, potassium, and hematocrit levels, and returns the sample to the patient. Main Outcome Measures The total volume and number of RBC transfusions during the first 2 weeks of life and the total volume of blood removed for laboratory testing. Results The trial was terminated prematurely when one center's NICU changed its standard method of laboratory testing. In the first 2 weeks of life, there was a nonsignificant 17% lower cumulative RBC transfusion volume in the monitor group (n = 46), compared with the control group (n = 47). However, data from the first week only (the period of greater catheter use) demonstrated a significant 33% lower cumulative RBC transfusion volume in the monitor group. Cumulative phlebotomy loss was ~25% less in the monitor group throughout the 2-week study period. There was no difference between groups in neonatal mortality, morbidity, and neurodevelopmental outcome rates at 18 to 24 months. This is the first randomized trial documenting that RBC

  10. Open and Closed Endotracheal Suctioning and Arterial Blood Gas Values: A Single-Blind Crossover Randomized Clinical Trial

    PubMed Central

    Faraji, Azam; Khatony, Alireza; Moradi, Gholamreza; Abdi, Alireza; Rezaei, Mansour

    2015-01-01

    Aim. This study was aimed at comparing the effects of the open and closed suctioning techniques on the arterial blood gas values in patients undergoing open-heart surgery. Methods. In a clinical trial, we recruited 42 patients after open-heart surgery in an educational hospital. Each patient randomly underwent both open and closed suctioning. ABGs, PaO2, SaO2, PaCO2, were analyzed before and one, five, and fifteen minutes after each suctioning episode. Results. At first the pressure of oxygen in arterial blood increased; however, this increase in the open technique was greater than that of the closed system (P < 0.001). The pressure of oxygen decreased five and fifteen minutes after both suctioning techniques (P < 0.05). The trends of carbon dioxide variations after the open and closed techniques were upward and downward, respectively. Moreover, the decrease in the level of oxygen saturation five and fifteen minutes after the open suctioning was greater than that of the closed suctioning technique (P < 0.05).  Conclusion. Arterial blood gas disturbances in the closed suctioning technique were less than those of the open technique. Therefore, to eliminate the unwanted effects of endotracheal suctioning on the arterial blood gases, the closed suctioning technique is recommended. PMID:26425366

  11. Comparison of gas analyzers for quantifying eddy covariance fluxes- results from an irrigated alfalfa field in Davis, CA

    NASA Astrophysics Data System (ADS)

    Chan, S.; Biraud, S.; Polonik, P.; Billesbach, D.; Hanson, C. V.; Bogoev, I.; Conrad, B.; Alstad, K. P.; Burba, G. G.; Li, J.

    2015-12-01

    The eddy covariance technique requires simultaneous, rapid measurements of wind components and scalars (e.g., water vapor, carbon dioxide) to calculate the vertical exchange due to turbulent processes. The technique has been used extensively as a non-intrusive means to quantify land-atmosphere exchanges of mass and energy. A variety of sensor technologies and gas sampling designs have been tried. Gas concentrations are commonly measured using infrared or laser absorption spectroscopy. Open-path sensors directly sample the ambient environment but suffer when the sample volume is obstructed (e.g., rain, dust). Closed-path sensors utilize pumps to draw air into the analyzer through inlet tubes which can attenuate the signal. Enclosed-path sensors are a newer, hybrid of the open- and closed-path designs where the sensor is mounted in the environment and the sample is drawn through a short inlet tube with short residence time. Five gas analyzers were evaluated as part of this experiment: open-path LI-COR 7500A, enclosed-path LI-COR 7200, closed-path Picarro G2311-f, open-path Campbell Scientific IRGASON, and enclosed-path Campbell Scientific EC155. We compared the relative performance of the gas analyzers over an irrigated alfalfa field in Davis, CA. The field was host to a range of ancillary measurements including below-ground sensors, and a weighing lysimeter. The crop was flood irrigated and harvested monthly. To compare sensors, we evaluated the half-hour mean and variance of gas concentrations (or mole densities). Power spectra for the gas analyzers and turbulent fluxes (from a common sonic anemometer) were also calculated and analyzed. Eddy covariance corrections will be discussed as they relate to sensor design (e.g., density corrections, signal attenuation).

  12. Resource planning for gas utilities: Using a model to analyze pivotal issues

    SciTech Connect

    Busch, J.F.; Comnes, G.A.

    1995-11-01

    With the advent of wellhead price decontrols that began in the late 1970s and the development of open access pipelines in the 1980s and 90s, gas local distribution companies (LDCs) now have increased responsibility for their gas supplies and face an increasingly complex array of supply and capacity choices. Heretofore this responsibility had been share with the interstate pipelines that provide bundled firm gas supplies. Moreover, gas supply an deliverability (capacity) options have multiplied as the pipeline network becomes increasing interconnected and as new storage projects are developed. There is now a fully-functioning financial market for commodity price hedging instruments and, on interstate Pipelines, secondary market (called capacity release) now exists. As a result of these changes in the natural gas industry, interest in resource planning and computer modeling tools for LDCs is increasing. Although in some ways the planning time horizon has become shorter for the gas LDC, the responsibility conferred to the LDC and complexity of the planning problem has increased. We examine current gas resource planning issues in the wake of the Federal Energy Regulatory Commission`s (FERC) Order 636. Our goal is twofold: (1) to illustrate the types of resource planning methods and models used in the industry and (2) to illustrate some of the key tradeoffs among types of resources, reliability, and system costs. To assist us, we utilize a commercially-available dispatch and resource planning model and examine four types of resource planning problems: the evaluation of new storage resources, the evaluation of buyback contracts, the computation of avoided costs, and the optimal tradeoff between reliability and system costs. To make the illustration of methods meaningful yet tractable, we developed a prototype LDC and used it for the majority of our analysis.

  13. Industrial SO2 emissions monitoring using a portable multi-channel gas analyzer with an optimized retrieval algorithm

    NASA Astrophysics Data System (ADS)

    Sun, Y. W.; Liu, C.; Xie, P. H.; Hartl, A.; Chan, K. L.; Tian, Y.; Wang, W.; Qin, M.; Liu, J. G.; Liu, W. Q.

    2015-12-01

    In this paper, we demonstrate achieving accurate industrial SO2 emissions monitoring using a portable multi-channel gas analyzer with an optimized retrieval algorithm. The introduced analyzer features with large dynamic measurement range and correction of interferences from other co-existing infrared absorbers, e.g., NO, CO, CO2, NO2, CH4, HC, N2O and H2O. Both effects have been the major limitations of industrial SO2 emissions monitoring. The multi-channel gas analyzer measures 11 different wavelength channels simultaneously in order to achieve correction of several major problems of an infrared gas analyzer, including system drift, conflict of sensitivity, interferences among different infrared absorbers and limitation of measurement range. The optimized algorithm makes use of a 3rd polynomial rather than a constant factor to quantify gas-to-gas interference. The measurement results show good performance in both linear and nonlinear range, thereby solving the problem that the conventional interference correction is restricted by the linearity of both intended and interfering channels. The result implies that the measurement range of the developed multi-channel analyzer can be extended to the nonlinear absorption region. The measurement range and accuracy are evaluated by experimental laboratory calibration. An excellent agreement was achieved with a Pearson correlation coefficient (r2) of 0.99977 with measurement range from ~5 ppmv to 10 000 ppmv and measurement error <2 %. The instrument was also deployed for field measurement. Emissions from 3 different factories were measured. The emissions of these factories have been characterized with different co-existing infrared absorbers, covering a wide range of concentration levels. We compared our measurements with the commercial SO2 analyzers. The overall good agreements are achieved.

  14. Comparison of a human portable glucometer and an automated chemistry analyzer for measurement of blood glucose concentration in pet ferrets (Mustela putorius furo)

    PubMed Central

    Summa, Noémie M.; Eshar, David; Lee-Chow, Bridget; Larrat, Sylvain; Brown, Dorothy C.

    2014-01-01

    This study compared blood glucose concentrations measured with a portable blood glucometer and a validated laboratory analyzer in venous blood samples of 20 pet ferrets (Mustela putorius furo). Correlation and agreement were evaluated with a Bland-Altman plot method and Lin’s concordance correlation coefficient. Blood glucose concentrations measured with the laboratory analyzer and the glucometer ranged from 1.9 to 8.6 mmol/L and from 0.9 to 9.2 mmol/L, respectively. The glucometer had a poor agreement and correlation with the laboratory analyzer (bias, −0.13 mmol/L; level of agreement, −2.0 to 3.6 mmol/L, concordance correlation coefficient 0.665). The relative sensitivity and specificity of the portable blood glucometer for detection of hypoglycemia were 100% (95% CI: 66% to 100%) and 50% (95% CI: 20% to 80%), respectively. Positive and negative predictive values were 67% (95% CI: 39% to 87%) and 100% (95% CI: 46% to 100%), respectively. Based on these results, clinicians are advised to be cautious when considering the results from this handheld glucometer in pet ferrets, and blood glucose concentrations should be determined with a laboratory analyzer validated for this species. PMID:25183894

  15. Comparison of a human portable glucometer and an automated chemistry analyzer for measurement of blood glucose concentration in pet ferrets (Mustela putorius furo).

    PubMed

    Summa, Noémie M; Eshar, David; Lee-Chow, Bridget; Larrat, Sylvain; Brown, Dorothy C

    2014-09-01

    This study compared blood glucose concentrations measured with a portable blood glucometer and a validated laboratory analyzer in venous blood samples of 20 pet ferrets (Mustela putorius furo). Correlation and agreement were evaluated with a Bland-Altman plot method and Lin's concordance correlation coefficient. Blood glucose concentrations measured with the laboratory analyzer and the glucometer ranged from 1.9 to 8.6 mmol/L and from 0.9 to 9.2 mmol/L, respectively. The glucometer had a poor agreement and correlation with the laboratory analyzer (bias, -0.13 mmol/L; level of agreement, -2.0 to 3.6 mmol/L, concordance correlation coefficient 0.665). The relative sensitivity and specificity of the portable blood glucometer for detection of hypoglycemia were 100% (95% CI: 66% to 100%) and 50% (95% CI: 20% to 80%), respectively. Positive and negative predictive values were 67% (95% CI: 39% to 87%) and 100% (95% CI: 46% to 100%), respectively. Based on these results, clinicians are advised to be cautious when considering the results from this handheld glucometer in pet ferrets, and blood glucose concentrations should be determined with a laboratory analyzer validated for this species. PMID:25183894

  16. Effect of stratified inequality of blood flow on gas exchange in liquid-filled lungs.

    NASA Technical Reports Server (NTRS)

    West, J. B.; Maloney, J. E.; Castle, B. L.

    1972-01-01

    This investigation set out to answer two questions: (1) are the distal alveoli in the terminal lung units less well perfused than the proximal alveoli, i.e., is there stratification of blood flow; and (2) if so, does this enhance gas exchange in the presence of stratified inequality of ventilation. Excised dog lungs were ventilated with saline and perfused with blood. Following single inspirations of xenon 133 in saline and various periods of breath holding, the expired xenon concentration against volume was measured and it confirmed marked stratified inequality of ventilation under these conditions. By measuring the rate of depletion of xenon from alveoli during a period of blood flow, we showed that the alveoli which emptied at the end of expiration had 16% less blood flow than those exhaling earlier. However, by measuring the xenon concentration in pulmonary venous blood, we found that about 10% less tracer was transferred from the alveoli into the blood when the inspired xenon was stratified within the respiratory zone. Thus while stratification of blood flow was confirmed, it was shown to impair rather than enhance the efficiency of gas transfer.

  17. Blood

    MedlinePlus

    ... fight infection and are part of your body's defense system. Platelets help blood to clot when you have a cut or wound. Bone marrow, the spongy material inside your bones, makes new blood cells. Blood cells ...

  18. A multivariate statistical analysis approach to analyze gas chromatography-olfactometry data of tangerine hybrids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gas chromatography (GC) hyphenated with olfactometry (O) when a human subject smells the effluent of the GC is a useful technique to identify aroma activity of volatile compounds in a food. Many techniques have been developed, based on olfactory thresholds (CHARM analysis, AEDA), or based on psychop...

  19. Cardiac Morphology and Function, and Blood Gas Transport in Aquaporin-1 Knockout Mice

    PubMed Central

    Al-Samir, Samer; Wang, Yong; Meissner, Joachim D.; Gros, Gerolf; Endeward, Volker

    2016-01-01

    We have studied cardiac and respiratory functions of aquaporin-1-deficient mice by the Pressure-Volume-loop technique and by blood gas analysis. In addition, the morphological properties of the animals' hearts were analyzed. In anesthesia under maximal dobutamine stimulation, the mice exhibit a moderately elevated heart rate of < 600 min−1 and an O2 consumption of ~0.6 ml/min/g, which is about twice the basal rate. In this state, which is similar to the resting state of the conscious animal, all cardiac functions including stroke volume and cardiac output exhibited resting values and were identical between deficient and wildtype animals. Likewise, pulmonary and peripheral exchange of O2 and CO2 were normal. In contrast, several morphological parameters of the heart tissue of deficient mice were altered: (1) left ventricular wall thickness was reduced by 12%, (2) left ventricular mass, normalized to tibia length, was reduced by 10–20%, (3) cardiac muscle fiber cross sectional area was decreased by 17%, and (4) capillary density was diminished by 10%. As the P-V-loop technique yielded normal end-diastolic and end-systolic left ventricular volumes, the deficient hearts are characterized by thin ventricular walls in combination with normal intraventricular volumes. The aquaporin-1-deficient heart thus seems to be at a disadvantage compared to the wild-type heart by a reduced left-ventricular wall thickness and an increased diffusion distance between blood capillaries and muscle mitochondria. While under the present quasi-resting conditions these morphological alterations have no consequences for cardiac function, we expect that the deficient hearts will show a reduced maximal cardiac output. PMID:27252655

  20. Atmospheric pressure glow discharge generated in nitrogen-methane gas mixture: PTR-MS analyzes of the exhaust gas

    NASA Astrophysics Data System (ADS)

    Torokova, Lucie; Mazankova, Vera; Krcma, Frantisek; Mason, Nigel J.; Matejcik, Stefan

    2015-07-01

    This paper reports the results of an extensive study of with the in situ mass spectrometry analysis of gaseous phase species produced by an atmospheric plasma glow discharge in N2-CH4 gas mixtures (with methane concentrations ranging from 1% to 4%). The products are studied using proton-transfer-reaction mass spectrometry (PTR-MS). HCN and CH3CN are identified as the main gaseous products. Hydrazine, methanimine, methyldiazene, ethylamine, cyclohexadiene, pyrazineacetylene, ethylene, propyne and propene are identified as minor compounds. All the detected compounds and their relative abundances are determined with respect to the experimental conditions (gas composition and applied power). The same molecules were observed by the Cassini-Huygens probe in Titan's atmosphere (which has same N2-CH4 gas mixtures). Such, experiments show that the formation of such complex organics in atmospheres containing C, N and H, like that of Titan, could be a source of prebiotic molecules. Contribution to the topical issue "The 14th International Symposium on High Pressure Low Temperature Plasma Chemistry (HAKONE XIV)", edited by Nicolas Gherardi, Ronny Brandenburg and Lars Stollenwark

  1. Design of a diagnostic residual gas analyzer for the ITER divertor

    SciTech Connect

    Klepper, C Christopher; Biewer, T. M.; Graves, Van B; Andrew, P.; Marcus, Chris; Shimada, M.; Hughes, S.; Boussier, B.; Johnson, D. W.; Gardner, W. L.; Hillis, D. L.; Vayakis, G.; Vayakis, G.; Walsh, M.

    2015-01-01

    One of the ITER diagnostics having reached an advanced design stage is a diagnostic RGA for the divertor, i.e. residual gas analysis system for the ITER divertor, which is intended to sample the divertor pumping duct region during the plasma pulse and to have a response time compatible with plasma particle and impurity lifetimes in the divertor region. Main emphasis is placed on helium (He) concentration in the ducts, as well as the relative concentration between the hydrogen isotopes (H2, D2, T2). Measurement of the concentration of radiative gases, such as neon (Ne) and nitrogen (N2), is also intended. Numerical modeling of the gas flow from the sampled region to the cluster of analysis sensors, through a long (~8m long, ~110mm diameter) sampling pipe terminating in a pressure reducing orifice, confirm that the desired response time (~1s for He or D2) is achieved with the present design.

  2. A programmable palm-size gas analyzer for use in micro-autonomous systems

    NASA Astrophysics Data System (ADS)

    Gordenker, Robert J. M.; Wise, Kensall D.

    2012-06-01

    Gas analysis systems having small size, low power, and high selectivity are badly needed for defense (detection of explosives and chemical warfare agents), homeland security, health care, and environmental applications. This paper presents a palm-size gas chromatography system having analysis times of 5-50sec, detection limits less than 1ppb, and an average power dissipation less than one watt. It uses no consumables. The three-chip fluidic system consists of a preconcentrator, a 25cm-3m separation column, and a chemi-resistive detector and is supported by a microcomputer and circuitry for programmable temperature control. The entire system, including the mini-pump and battery, occupies less than 200cc and is configured for use on autonomous robotic vehicles.

  3. Gas analyzer for continuous monitoring of trace level methanethiol by microchannel collection and fluorescence detection.

    PubMed

    Toda, Kei; Kuwahara, Haruka; Kajiwara, Hidetaka; Hirota, Kazutoshi; Ohira, Shin-Ichi

    2014-09-01

    The highly odorous compound methanethiol, CH3SH, is commonly produced in biodegradation of biomass and industrial processes, and is classed as 2000 times more odorous than NH3. However, there is no simple analytical method for detecting low parts-per-billion in volume ratio (ppbv) levels of CH3SH. In this study, a micro gas analysis system (μGAS) was developed for continuous or near real time measurement of CH3SH at ppbv levels. In addition to a commercial fluorescence detector, a miniature high sensitivity fluorescence detector was developed using a novel micro-photomultiplier tube device. CH3SH was collected by absorption into an alkaline solution in a honeycomb-patterned microchannel scrubber and then mixed with the fluorescent reagent, 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F). Gaseous CH3SH was measured without serious interference from other sulfur compounds or amines. The limits of detection were 0.2ppbv with the commercial detector and 0.3ppbv with the miniature detector. CH3SH produced from a pulping process was monitored with the μGAS system and the data agreed well with those obtained by collection with a silica gel tube followed by thermal desorption-gas chromatography-mass spectrometry. The portable system with the miniature fluorescence detector was used to monitor CH3SH levels in near-real time in a stockyard and it was shown that the major odor component, CH3SH, presented and its concentration varied dynamically with time. PMID:25109855

  4. Tissue gas and blood analyses of human subjects breathing 80% argon and 20% oxygen

    NASA Technical Reports Server (NTRS)

    Horrigan, D. J.; Wells, C. H.; Guest, M. M.; Hart, G. B.; Goodpasture, J. E.

    1979-01-01

    Eight human volunteers, individually studied in a hyperbaric chamber, breathed: (1) air at 1 ATA; (2) 80% argon and 20% oxygen at 1 ATA for 30 min; (3) air at 1 ATA for 30 min; (4) 100% O2 at 1 ATA for 30 min; (5) air at 1 ATA for 30 min; (6) 100% O2 at 2 ATA for 60 min; and (7) 80% argon and 20% oxygen at 1 ATA for 30 min. Oxygen, carbon dioxide, nitrogen, and argon tensions were measured in muscle and subcutaneous tissue by mass spectroscopic analyses. Venous blood obtained at regular intervals was analyzed for coagulation and fibrinolytic factors. Inert gas narcosis was not observed. After breathing argon for 30 min, muscle argon tensions were almost three times the subcutaneous tensions. Argon wash-in mirrored nitrogen wash-out. Argon wash-in and wash-out had no effect on tissue PO2 or PCO2. Coagulation and fibrinolytic changes usually associated with vascular bubbles were absent.

  5. Robustness of arterial blood gas analysis for assessment of respiratory safety pharmacology in rats.

    PubMed

    Whiteside, Garth T; Hummel, Michele; Boulet, Jamie; Beyenhof, Jessica D; Strenkowski, Bryan; John, Janet Dell; Knappenberger, Terri; Maselli, Harry; Koetzner, Lee

    2016-01-01

    Whole body plethysmography using unrestrained animals is a common technique for assessing the respiratory risk of new drugs in safety pharmacology studies in rats. However, wide variations in experimental technique make cross laboratory comparison of data difficult and raise concerns that non-appropriate conditions may mask the deleterious effects of test compounds - in particular with suspected respiratory depressants. Therefore, the objective of this study was to evaluate the robustness of arterial blood gas analysis as an alternative to plethysmography in rats. We sought to do this by assessing the effect of different vehicles and times post-surgical catheterization on blood gas measurements, in addition to determining sensitivity to multiple opioids. Furthermore, we determined intra-lab variability from multiple datasets utilizing morphine and generated within a single lab and lastly, inter-lab variability was measured by comparing datasets generated in two separate labs. Overall, our data show that arterial blood gas analysis is a measure that is both flexible in terms of experimental conditions and highly sensitive to respiratory depressants, two key limitations when using plethysmography. As such, our data strongly advocate the adoption of arterial blood gas analysis as an investigative approach to reliably examine the respiratory depressant effects of opioids. PMID:26589431

  6. Effects of zilpaterol hydrochloride on blood gas, electrolyte balance, and pH in feedlot cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to examine the effects of zilpaterol hydrochloride (ZH) on blood gas, electrolyte balance and pH in feedlot cattle. Black-hided steers and heifers (n=96) were sourced from a commercial feedlot and transported to the Texas Tech University Beef Center in New Deal, TX. C...

  7. Could We Apply a NeuroProcessor For Analyzing a Gas Response Of Multisensor Arrays?

    SciTech Connect

    Sysoev, V. V.; Musatov, V. Yu.; Maschenko, A. A.; Varegnikov, A. S.; Chrizostomov, A. A.; Kiselev, I.; Schneider, T.; Bruns, M.; Sommer, M.

    2009-05-23

    We describe an effort of implementation of hardware neuroprocessor to carry out pattern recognition of signals generated by a multisensor microarray of Electronic Nose type. The multisensor microarray is designed with the SnO{sub 2} thin film segmented by co-planar electrodes according to KAMINA (KArlsruhe Micro NAse) E-nose architecture. The response of this microarray to reducing gases mixtured with a synthetic air is processed by principal component analysis technique realized in PC (Matlab software) and the neural microprocessor NeuroMatrix NM6403. It is shown that the neuroprocessor is able to successfully carry out a gas-recognition algorithm at a real-time scale.

  8. Optimized design of substrate-integrated hollow waveguides for mid-infrared gas analyzers

    NASA Astrophysics Data System (ADS)

    Fortes, Paula Regina; Flávio da Silveira Petruci, João; Wilk, Andreas; Alves Cardoso, Arnaldo; Milton Raimundo, Ivo, Jr.; Mizaikoff, Boris

    2014-09-01

    Design and analytical performance studies are presented for optimizing a new generation of hollow waveguides suitable for quantitative gas sensing—the so-called substrate-integrated hollow waveguide (iHWG). Taking advantage of a particularly compact Fourier transform infrared spectrometer optimized iHWG geometries are investigated toward the development of a multi-constituent breath analysis tool compatible for usage, e.g., in exhaled mouse breath analysis. Three different iHWG geometries were compared, i.e., straight, meandering one-turn and meandering two-turn waveguide channels aiming at maximizing the related analytical figures-of-merit including the achievable limits of detection for selected exemplary analytes. In addition, efficient coupling of infrared (IR) radiation into straight iHWGs was investigated using integrated optical funnel structures. Calibration functions of butane in nitrogen serving as IR-transparent matrix gas were established and compared for the various iHWG geometries. Given the tidal volume of exhaled breath (EB) samples ranging from a few hundreds of milliliters (human, swine) to a few hundreds of microliters (mouse), it is essential for any given analysis to select an appropriate waveguide geometry and volume yet maintaining (i) a compact footprint ensuring hand-held instrumentation, (ii) modular exchange of the iHWG according to the analysis requirement yet with constant device format, and (iii) enabling inline/online measurement capabilities toward continuous EB diagnostics.

  9. Dual beam Doppler FD-OCT system with integrated Dynamic Vessel Analyzer and rotatable beams to measure total retinal blood flow

    NASA Astrophysics Data System (ADS)

    Doblhoff-Dier, Veronika; Werkmeister, René M.; Gröschl, Martin; Schmetterer, Leopold

    2014-03-01

    We present a method capable of measuring the total retinal blood flow in arteries and veins based on dual beam Fourierdomain Doppler optical coherence tomography (OCT) in combination with a fundus camera based Dynamic Vessel Analyzer. Incorporating a Dynamic vessel analyzer into the system not only gives a live image of the fundus - it also allows determining the vessels' diameter precisely during the OCT measurement, which is necessary for the determination of the blood flow. While dual beam systems with fixed detection plane allow only vessels with certain orientations to be measured, the detection plane of our system can be rotated by 90°. This ensures that the blood's velocity can be measured in all vessels around the optic nerve head. The results of the total blood flow measurements are in the same range as previously published data. Additionally, the high degree of conformity between the measured venous and arterial flow corroborated the system's validity. For larger vessels, the logarithmic values of vessel diameter and blood flow were found to be related linearly with a regression coefficient of around 3, which is in accordance with Murray's law. For smaller vessels (diameter below 60 μm), the values diverge from the linear dependence. The high sensitivity and the good agreement with published data suggest a high potential for examining the retinal blood flow in patients with ocular diseases.

  10. Impact of arterial blood gas analysis in disability evaluation of the bituminous coal miner with simple pneumoconiosis

    SciTech Connect

    Fields, C.L.; Roy, T.M.; Dow, F.T.; Anderson, W.H. )

    1992-04-01

    The Department of Labor has set guidelines for the use of resting arterial blood gas analysis in determination of total and permanent disability for coal workers' pneumoconiosis. To determine the prevalence with which bituminous coal miners fall below the arterial tensions of both oxygen and carbon dioxide published in the Federal Register, we studied 1012 miners who had both reproducible spirometry and arterial blood gas analysis as part of their disability evaluation. Eighty-seven percent of impaired miners could be identified by the spirometric criteria. Thirteen percent of impaired bituminous coal miners had acceptable pulmonary function but were eligible for black lung benefits by the blood gas guidelines. This population would have been missed if blood gas analysis were excluded from the evaluation process. On the other hand, approximately 25% of the blood gas analyses that were performed could be eliminated if a policy was adopted to do this test only on miners with spirometry that exceed the federal guidelines.

  11. The oxygen status algorithm: a computer program for calculating and displaying pH and blood gas data.

    PubMed

    Siggaard-Andersen, O; Siggaard-Andersen, M

    1990-01-01

    Input parameters for the program are the arterial pH, pCO2, and pO2 (measured by a blood gas analyzer), oxygen saturation, carboxy-, met-, and total hemoglobin (measured by a multi-wavelength spectrometer), supplemented by patient age, sex, temperature, inspired oxygen fraction, fraction of fetal hemoglobin, and ambient pressure. Output parameters are the inspired and alveolar oxygen partial pressures, pH,pCO2 and pO2 referring to the actual patient temperature, estimated shunt fraction, half-saturation tension, estimated 2,3-diphosphoglycerate concentration, oxygen content and oxygen capacity, extracellular base excess, and plasma bicarbonate concentration. Three parameters related to the blood oxygen availability are calculated: the oxygen extraction tension, concentration of extractable oxygen, and oxygen compensation factor. Calculations of the 'reverse' type may also be performed so that the effect of therapeutic measures on the oxygen status or the acid-base status can be predicted. The user may choose among several different units of measurement and two different conventions for symbols. The results are presented in a data display screen comprising all quantities together with age, sex, and temperature adjusted reference values. The program generates a 'laboratory diagnosis' of the oxygen status and the acid-base status and three graphs illustrating the oxygen status and the acid-base status of the patient: the oxygen graph, the acid-base chart and the blood gas map. A printed summary in one A4 page including a graphical display can be produced with an Epson or HP Laser compatible printer. The program is primarily intended for routine laboratories with a blood gas analyzer combined with a multi-wavelength spectrometer. Calculating the derived quantities may enhance the usefulness of the analyzers and improve patient care. The program may also be used as a teaching aid in acid-base and respiratory physiology. The program requires an IBM PC, XT, AT or similar

  12. Fabrication and characterization of a CNT forest integrated micromechanical resonator for a rarefied gas analyzer in a medium vacuum atmosphere

    NASA Astrophysics Data System (ADS)

    Sugano, Koji; Matsumoto, Ryu; Tsutsui, Ryota; Kishihara, Hiroyuki; Matsuzuka, Naoki; Yamashita, Ichiro; Uraoka, Yukiharu; Isono, Yoshitada

    2016-07-01

    This study focuses on the development of a multi-walled carbon nanotube (MWCNT) forest integrated micromechanical resonator working as a rarefied gas analyzer for nitrogen (N2) and hydrogen (H2) gases in a medium vacuum atmosphere. The resonant response is detected in the form of changes in the resonant frequency or damping effects, depending on the rarefied gas species. The carbon nanotube (CNT) forest on the resonator enhances the effective specific surface area of the resonator, such that the variation of the resonant frequency and the damping effect based on the gas species increase significantly. We developed the fabrication process for the proposed resonator, which consists of standard micro-electro-mechanical systems (MEMS) processes and high-density CNT synthesis on the resonator mass. The high-density CNT synthesis was realized using multistep alternate coating of two types of ferritin proteins that act as catalytic iron particles. Two devices with different CNT densities were fabricated and characterized to evaluate the effect of the surface area of the CNT forest on the resonant response as a function of gas pressures ranging from 0.011 to 1 Pa for N2 and H2. Considering the damping effect, we found that the device with higher density was able to distinguish N2 and H2 clearly, whereas the device with lower density showed no difference between N2 and H2. We confirmed that a larger surface area showed a higher damping effect. These results were explained based on the kinetic theory of gases. In the case of resonant frequency, the relative resonant frequency shift increased with gas pressure and surface area because of the adsorption of gas molecules on the resonator surfaces. Higher density CNT forest adsorbed more gas molecules on the surfaces. The developed CNT forest integrated micromechanical resonator could successfully detect N2 and H2 gases and distinguish between them under pressures of 1 Pa.

  13. Possible Calcite and Magnesium Perchlorate Interaction in the Mars Phoenix Thermal and Evolved Gas Analyzer (TEGA)

    NASA Technical Reports Server (NTRS)

    Cannon, K. M.; Sutter, B.; Ming, D. W.; Boynton, W. V.; Quinn, R. C.

    2012-01-01

    The Mars Phoenix Lander's TEGA instrument detected a calcium carbonate phase decomposing at high temperatures (approx.700 C) from the Wicked Witch soil sample [1]. TEGA also detected a lower temperature CO2 release between 400 C and 680 C [1]. Possible explanations given for this lower temperature CO2 release include thermal decomposition of Mg or Fe carbonates, a zeolitictype desorption reaction, or combustion of organic compounds in the soil [2]. The detection of 0.6 wt % soluble perchlorate by the Wet Chemistry Laboratory (WCL) on Phoenix [3] has implications for the possibility of organic molecules in the soil. Ming et al. [4] demonstrated that perchlorates could have oxidized organic compounds to CO2 in TEGA, preventing detection of their characteristic mass fragments. Here, we propose that a perchlorate salt and calcium carbonate present in martian soil reacted to produce the 400 C - 680 C TEGA CO2 release. The parent salts of the perchlorate on Mars are unknown, but geochemical models using WCL data support the possible dominance of Mg-perchlorate salts [5]. Mg(ClO4)2 6H2O is the stable phase at ambient martian conditions [6], and breaks down at lower temperatures than carbonates giving off Cl2 and HCl gas [7,8]. Devlin and Herley [7] report two exotherms at 410-478 C and 473-533 C which correspond to the decomposition of Mg(ClO4)2.

  14. A gas-phase chemiluminescence-based analyzer for waterborne arsenic

    USGS Publications Warehouse

    Idowu, A.D.; Dasgupta, P.K.; Genfa, Z.; Toda, K.; Garbarino, J.R.

    2006-01-01

    We show a practical sequential injection/zone fluidics-based analyzer that measures waterborne arsenic. The approach is capable of differentiating between inorganic As(III) and As(V). The principle is based on generating AsH 3 from the sample in a confined chamber by borohydride reduction at controlled pH, sparging the chamber to drive the AsH3 to a small reflective cell located atop a photomultiplier tube, allowing it to react with ozone generated from ambient air, and measuring the intense chemiluminescence that results. Arsine generation and removal from solution results in isolation from the sample matrix, avoiding the pitfalls encountered in some solution-based analysis techniques. The differential determination of As(III) and As(V) is based on the different pH dependence of the reducibility of these species to AsH3. At pH ???1, both As(III) and As(V) are quantitatively converted to arsine in the presence of NaBH4. At a pH of 4-5, only As(III) is converted to arsine. In the present form, the limit of detection (S/N = 3) is 0.05 ??g/L As at pH ???1 and 0.09 ??g/L As(III) at pH ???4-5 for a 3-mL sample. The analyzer is intrinsically automated and requires 4 min per determination. It is also possible to determine As(III) first at pH 4.5 and then determine the remaining As in a sequential manner; this requires 6 min. There are no significant practical interferences. A new borohydride solution formulation permits month-long reagent stability. ?? 2006 American Chemical Society.

  15. Doping control for metandienone using hair analyzed by gas chromatography-tandem mass spectrometry.

    PubMed

    Bresson, Marie; Cirimele, Vincent; Villain, Marion; Kintz, Pascal

    2006-05-19

    A sensitive, specific and reproducible method for the quantitative determination of the anabolic metandienone in human hair has been developed. The preparation involved a decontamination step with methylene chloride. The hair sample (about 50 mg) was solubilised in 1 ml 1 M NaOH, 10 min at 95 degrees C, in presence of 2 ng of nandrolone-d(3) used as internal standard. The homogenate was neutralized and extracted using consecutively a solid-phase extraction (Isolute C(18) eluted with methanol) and a liquid-liquid extraction with pentane. The residue was derivatized by adding 5 microl MSTFA/NH(4)I/2-mercaptoethanol (250 microl; 5 mg; 15 microl) and 45 microl MSTFA, then incubated for 20 min at 60 degrees C. A 1 microl aliquot of derivatized extract was injected into the column (HP5-MS capillary column, 5% phenyl-95% methylsiloxane, 30 m x 0.32 mm i.d., 0.25 microm film thickness) of a Hewlett Packard (Palo Alto, CA, USA) gas chromatograph (6890 Series). Metandienone was identified using three transitions (its daughter ions at m/z 339 and 206 for the parent 444 and 191 for 206) using a Waters Quattro Micro MS-MS system. The transition m/z 444 to 206 has been used as quantification transition and the others as identification transitions. The assay was capable of detecting 2 pg/mg of metandienone when approximately 50 mg of hair material was processed. Linearity was observed for metandienone concentrations ranging from 2 to 500 pg/mg with a correlation coefficient of 0.9997. Intra-day and between-day precisions at 50 pg/mg were 13.4-16.5% and 22.0%, respectively, with an extraction recovery of 48%. The analysis of hair, cut into four segments, obtained from an athlete, revealed the presence of metandienone at the concentrations of 78, 7, 10 and 108 pg/mg in each segment of hair (0-1, 1-2, 2-3 and 3 cm to the tip). PMID:16597518

  16. Analysis of whole blood samples with low gas flow inductively coupled plasma-optical emission spectrometry.

    PubMed

    Nowak, Sascha; Künnemeyer, Jens; Terborg, Lydia; Trümpler, Stefan; Günsel, Andreas; Wiesmüller, Gerhard A; Karst, Uwe; Buscher, Wolfgang

    2015-01-01

    Low gas flow ICP-OES with a total argon consumption below 0.7 L/min is introduced for the analysis of trace elements in blood samples to investigate the influence of samples containing an organic solvent in a demanding matrix on the performance of this plasma for the first time. Therefore, gadolinium was determined in human plasma samples and mercury in red blood cells, human plasma, and precipitated plasma protein fraction. Limits of detection (LOD) were determined to be in the low microgram per liter range for the analytes and the accuracy of the method was assessed by comparison with a conventional Fassel-type torch-based ICP-OES. It was proven that the low gas flow ICP-OES leads to comparable results with the instrument based on the Fassel-type torch. PMID:25240935

  17. Performance Evaluation of a New, Tunable-Diode Laser Trace-Gas Analyzer for Isotope Ratios of Carbon Dioxide

    NASA Astrophysics Data System (ADS)

    Sargent, S.

    2015-12-01

    Newly available interband cascade lasers (ICLs) have enabled the development of a family of tunable-diode laser trace-gas analyzers that do not require liquid nitrogen to cool the laser. The lasers are available in the 3000 to 6000 nm range, providing access to the strong mid-infrared absorption lines for important gases such as methane, nitrous oxide, and carbon dioxide. These ICLs are fabricated with distributed feedback to improve their stability and spectroscopic quality. A recently released trace-gas analyzer for carbon dioxide isotopes (TGA200A, Campbell Scientific, Inc.) was evaluated for short- and long-term precision using Allan variance. Accuracy and linearity of CO2 mole fraction was assessed with a set of seven NOAA standard reference gases ranging from 298.35 to 971.48 ppm. Dilution of high-concentration CO2 with CO2-free air demonstrated the linearity of isotope ratio measurements beyond 1000 ppm CO2. Two analyzer variants were tested: one for CO2, δ13C and δ18O; and the other for CO2 and δ13C at enhanced precision.

  18. A comprehensive two-dimensional gas chromatography method for analyzing extractable petroleum hydrocarbons in water and soil.

    PubMed

    Seeley, Stacy K; Bandurski, Steven V; Brown, Robert G; McCurry, James D; Seeley, John V

    2007-01-01

    A flow-switching two-dimensional gas chromatography (GCxGC) apparatus has been constructed that can operate at temperatures as high as 340 degrees C. This system is employed to analyze complex hydrocarbon mixtures such as diesel fuel, gas-oil, motor oil, and petroleum contaminated environmental samples. The GCxGC system generates two-dimensional chromatograms with minimal overlap between the aliphatic and aromatic regions This allows these compound classes to be independently quantitated without prior fractionation. The GCxGC system is used to analyze extracts of spiked water samples, wastewater, and soil. The accuracy of the method is compared to that of the Massachusetts Extractable Petroleum Hydrocarbons (MA EPH) method. The GCxGC system generates a quantitative accuracy similar to the MA EPH method for the analysis of spiked water samples. The GCxGC method and the MA EPH method generate comparable levels of total hydrocarbons when wastewater is analyzed, but the GCxGC method detects a significantly higher aromatic content and lower aliphatic content. Both the GCxGC method and MA EPH method measure comparable levels of aromatics in the soil samples. PMID:18078573

  19. Surftherm: A program to analyze thermochemical and kinetic data in gas-phase and surface chemical reaction mechanisms

    SciTech Connect

    Coltrin, M.E.; Moffat, H.K.

    1994-06-01

    This report documents the Surftherm program that analyzes transport coefficient, thermochemical- and kinetic rate information in complex gas-phase and surface chemical reaction mechanisms. The program is designed for use with the Chemkin (gas-phase chemistry) and Surface Chemkin (heterogeneous chemistry) programs. It was developed as a ``chemist`s companion`` in using the Chemkin packages with complex chemical reaction mechanisms. It presents in tabular form detailed information about the temperature and pressure dependence of chemical reaction rate constants and their reverse rate constants, reaction equilibrium constants, reaction thermochemistry, chemical species thermochemistry and transport properties. This report serves as a user`s manual for use of the program, explaining the required input and the output.

  20. Early Blood Gas Predictors of Bronchopulmonary Dysplasia in Extremely Low Gestational Age Newborns

    PubMed Central

    Sriram, Sudhir; Schreiber, Michael D.; Batton, Daniel G.; Shah, Bhavesh; Bose, Carl; Van Marter, Linda J.; Allred, Elizabeth N.; Leviton, Alan

    2014-01-01

    Aim. To determine among infants born before the 28th week of gestation to what extent blood gas abnormalities during the first three postnatal days provide information about the risk of bronchopulmonary dysplasia (BPD). Methods. We studied the association of extreme quartiles of blood gas measurements (hypoxemia, hyperoxemia, hypocapnea, and hypercapnea) in the first three postnatal days, with bronchopulmonary dysplasia, among 906 newborns, using multivariable models adjusting for potential confounders. We approximated NIH criteria by classifying severity of BPD on the basis of the receipt of any O2 on postnatal day 28 and at 36 weeks PMA and assisted ventilation. Results. In models that did not adjust for ventilation, hypoxemia was associated with increased risk of severe BPD and very severe BPD, while infants who had hypercapnea were at increased risk of very severe BPD only. In contrast, infants who had hypocapnea were at reduced risk of severe BPD. Including ventilation for 14 or more days eliminated the associations with hypoxemia and with hypercapnea and made the decreased risk of very severe BPD statistically significant. Conclusions. Among ELGANs, recurrent/persistent blood gas abnormalities in the first three postnatal days convey information about the risk of severe and very severe BPD. PMID:24959184

  1. The use of blood gas parameters to predict ascites susceptibility in juvenile broilers.

    PubMed

    van As, P; Elferink, M G; Closter, A M; Vereijken, A; Bovenhuis, H; Crooijmans, R P M A; Decuypere, E; Groenen, M A M

    2010-08-01

    Ascites syndrome is a metabolic disorder found in modern broilers that have insufficient pulmonary vascular capacity. Commercial breeding programs have heavily focused on high growth rate, which led to fast-growing chickens, but as a negative consequence, the incidence of ascites syndrome increased. However, not all birds with a high growth rate will suffer from ascites syndrome, which might indicate a genetic susceptibility to ascites. Information on blood gas parameters measured early in life and their relation to ascites susceptibility is expected to contribute to identification on the cause of ascites syndrome. In this study, several physiological parameters, such as blood gas parameters [pH, partial pressure of CO(2) in venous blood (pvCO(2)), and partial pressure of O(2) in venous blood], hematocrit, electrolytes (Na(+), Ca(2+), and K(+)), metabolites (lactate and glucose), were measured at d 11 to 12 of age from 100 female and 100 male broilers. From d 14 onward, the birds were challenged to provoke the development of ascites syndrome. Our results showed that high pvCO(2) values together with low pH values (males) or high pH values (females) in the venous blood of juvenile broilers coincided with ascites. Therefore, blood pvCO(2) and pH in both juvenile male and female broilers seem to be critical factors in ascites pathophysiology and can be used as phenotypic traits to predict ascites susceptibility in juvenile broilers at d 11 to 12. A prediction model was built on a subpopulation of the broilers without any loss in sensitivity (0.52) and specificity (0.78) when applied to the validation population. The parameter sex was included in the prediction model because levels of pvCO(2) and pH that associated with ascites susceptibility are different between males and females. Commercial breeders can include these phenotypic traits in their genetic selection programs to reduce the incidence of ascites syndrome. PMID:20634524

  2. Optimization of an enclosed gas analyzer sampling system for measuring eddy covariance fluxes of H2O and CO2

    NASA Astrophysics Data System (ADS)

    Metzger, Stefan; Burba, George; Burns, Sean P.; Blanken, Peter D.; Li, Jiahong; Luo, Hongyan; Zulueta, Rommel C.

    2016-03-01

    Several initiatives are currently emerging to observe the exchange of energy and matter between the earth's surface and atmosphere standardized over larger space and time domains. For example, the National Ecological Observatory Network (NEON) and the Integrated Carbon Observing System (ICOS) are set to provide the ability of unbiased ecological inference across ecoclimatic zones and decades by deploying highly scalable and robust instruments and data processing. In the construction of these observatories, enclosed infrared gas analyzers are widely employed for eddy covariance applications. While these sensors represent a substantial improvement compared to their open- and closed-path predecessors, remaining high-frequency attenuation varies with site properties and gas sampling systems, and requires correction. Here, we show that components of the gas sampling system can substantially contribute to such high-frequency attenuation, but their effects can be significantly reduced by careful system design. From laboratory tests we determine the frequency at which signal attenuation reaches 50 % for individual parts of the gas sampling system. For different models of rain caps and particulate filters, this frequency falls into ranges of 2.5-16.5 Hz for CO2, 2.4-14.3 Hz for H2O, and 8.3-21.8 Hz for CO2, 1.4-19.9 Hz for H2O, respectively. A short and thin stainless steel intake tube was found to not limit frequency response, with 50 % attenuation occurring at frequencies well above 10 Hz for both H2O and CO2. From field tests we found that heating the intake tube and particulate filter continuously with 4 W was effective, and reduced the occurrence of problematic relative humidity levels (RH > 60 %) by 50 % in the infrared gas analyzer cell. No further improvement of H2O frequency response was found for heating in excess of 4 W. These laboratory and field tests were reconciled using resistor-capacitor theory, and NEON's final gas sampling system was developed on this

  3. Robotic Arm Camera Image of the South Side of the Thermal and Evolved-Gas Analyzer (Door TA4

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Thermal and Evolved-Gas Analyzer (TEGA) instrument aboard NASA's Phoenix Mars Lander is shown with one set of oven doors open and dirt from a sample delivery. After the 'seventh shake' of TEGA, a portion of the dirt sample entered the oven via a screen for analysis. This image was taken by the Robotic Arm Camera on Sol 18 (June 13, 2008), or 18th Martian day of the mission.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  4. A Volatile Organic Analyzer for Space Station - Description and evaluation of a gas chromatography/ion mobility spectrometer

    NASA Technical Reports Server (NTRS)

    Limero, Thomas; Brokenshire, John; Cumming, Colin; Overton, ED; Carney, Ken; Cross, Jay; Eiceman, Gary; James, John

    1992-01-01

    An on-board Volatile Organic Analyzer (VOA), an essential component of the Environmental Health System (EHS) air-quality monitoring strategy, is described. The strategy is aimed at warning the crew and ground personnel if volatile compounds exceed safe exposure limits. The VOA uses a combination of gas chromatography (GC) and ion-mobility spectrometry (IMS) for environmental monitoring and analysis. It is concluded that the VOA dual-mode detection capability and the ion mobilities in the drift region are unique features that can assist in the resolution of coeluting GC peaks. The VOA is capable of accurately identifying and quantifying target compounds in a complex mixture.

  5. Analyzing the adsorption of blood plasma components by means of fullerene-containing silica gels and NMR spectroscopy in solids

    NASA Astrophysics Data System (ADS)

    Melenevskaya, E. Yu.; Mokeev, M. V.; Nasonova, K. V.; Podosenova, N. G.; Sharonova, L. V.; Gribanov, A. V.

    2012-10-01

    The results from studying the adsorption of blood plasma components (e.g., protein, triglycerides, cholesterol, and lipoproteins of low and high density) using silica gels modified with fullerene molecules (in the form of C60 or the hydroxylated form of C60(OH) x ) and subjected to hydration (or, alternatively, dehydration) are presented. The conditions for preparing adsorbents that allow us to control the adsorption capacity of silica gel and the selectivity of adsorption toward the components of blood plasma, are revealed. The nature and strength of the interactions of the introduced components (fullerene molecules and water) with functional groups on the silica surface are studied by means of solid state NMR spectroscopy (NMR-SS). Conclusions regarding the nature of the centers that control adsorption are drawn on the basis of NMR-SS spectra in combination with direct measurements of adsorption. The interaction of the oxygen of the hydroxyl group of silica gel with fullerene, leading to the formation of electron-donor complexes of C60-H, C60-OH, or C60-OSi type, is demonstrated by the observed changes in the NMR-SS spectra of silica gels in the presence of fullerene.

  6. BLOOD SUBSTITUTES: EVOLUTION FROM NON-CARRYING TO OXYGEN AND GAS CARRYING FLUIDS

    PubMed Central

    Cabrales, Pedro; Intaglietta, Marcos

    2013-01-01

    The development of oxygen (O2) carrying blood substitutes has evolved from the goal of replicating blood O2 transports properties to that of preserving microvascular and organ function, reducing the inherent or potential toxicity of the material used to carry O2, and treating pathologies initiated by anemia and hypoxia. Furthermore, the emphasis has shifted from blood replacement fluid to “O2 therapeutics” that restore tissue oxygenation to specific tissues regions. This review covers the different alternatives, potential and limitations of hemoglobin based O2 carriers (HBOCs) and perfluorocarbon based O2 carriers (PFCOCs), with emphasis on the physiological conditions disturbed in the situation that they will be used. It describes how concepts learned from plasma expanders without O2 carrying capacity can be applied to maintain O2 delivery and summarizes the microvascular responses due to HBOCs and PFCOCs. This review also presents alternative applications of HBOCs and PFCOCs namely: 1) How HBOC O2 affinity can be engineered to target O2 delivery to hypoxic tissues; and 2) How the high gas solubility of PFCOCs provides new opportunities for carrying, dissolving and delivering gases with biological activity. It is concluded that current blood substitutes development has amplified their applications horizon by devising therapeutic functions for oxygen carriers requiring limited O2 delivery capacity restoration. Conversely, full, blood-like O2 carrying capacity re-establishment awaits control of O2 carrier toxicity. PMID:23820271

  7. The effects of cytochalasin D and abciximab on hemostasis in canine whole blood assessed by thromboelastography and the PFA-100® platelet function analyzer system.

    PubMed

    Brainard, Benjamin M; Abed, Janan M; Koenig, Amie

    2011-07-01

    The selective inhibition of platelet function in whole blood coagulation testing may allow insights into the nature of hypercoagulability in dogs with critical illness. To determine the effects of cytochalasin D and abciximab on hemostatic parameters in canine citrated whole blood, an in-vitro study was designed using thromboelastography (TEG) and a platelet function analyzer (PFA-100®). 8 clinically healthy mixed breed dogs donated blood that was anticoagulated with 3.2% sodium citrate in a 9:1 blood-to-citrate ratio. Addition of cytochalasin D to citrated whole blood from 6 dogs at concentrations ranging from 0 µg/ml to 10 µg/ml caused a maximal reduction of TEG maximum amplitude (MA) at a concentration of 7.5 µg/ml (52.7 ± 4.3 to 14.3 ± 7.8 mm). Addition of abciximab to canine citrated whole blood at concentrations of either 20 µg/ml or 40 µg/ml did not affect the TEG tracing; however, addition of abciximab to citrated canine whole blood at concentrations of 10 µg/ml and 20 µg/ml significantly prolonged PFA-100 closure times (72.5 ± 15 to 149.2 ± 91 sec and 275.6 ± 54 sec, respectively, P < 0.04). Inhibition of canine platelet function by cytochalasin D is demonstrated by TEG, but abciximab did not change TEG tracings. Abciximab does, however, inhibit platelet aggregation under shear stress as measured by the PFA-100. Inhibition of canine platelet function with cytochalasin D may allow further TEG studies in dogs with clinical disease. PMID:21908311

  8. Assessing blood brain barrier dynamics or identifying or measuring selected substances or toxins in a subject by analyzing Raman spectrum signals of selected regions in the eye

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2003-01-01

    A non-invasive method for analyzing the blood-brain barrier includes obtaining a Raman spectrum of a selected portion of the eye and monitoring the Raman spectrum to ascertain a change to the dynamics of the blood brain barrier. Also, non-invasive methods for determining the brain or blood level of an analyte of interest, such as glucose, drugs, alcohol, poisons, and the like, comprises: generating an excitation laser beam (e.g., at a wavelength of 600 to 900 nanometers); focusing the excitation laser beam into the anterior chamber of an eye of the subject so that aqueous humor, vitreous humor, or one or more conjunctiva vessels in the eye is illuminated; detecting (preferably confocally detecting) a Raman spectrum from the illuminated portion of the eye; and then determining the blood level or brain level (intracranial or cerebral spinal fluid level) of an analyte of interest for the subject from the Raman spectrum. In certain embodiments, the detecting step may be followed by the step of subtracting a confounding fluorescence spectrum from the Raman spectrum to produce a difference spectrum; and determining the blood level and/or brain level of the analyte of interest for the subject from that difference spectrum, preferably using linear or nonlinear multivariate analysis such as partial least squares analysis. Apparatus for carrying out the foregoing methods are also disclosed.

  9. Assessing blood brain barrier dynamics or identifying or measuring selected substances, including ethanol or toxins, in a subject by analyzing Raman spectrum signals

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Borchert, Mark S. (Inventor)

    2008-01-01

    A non-invasive method for analyzing the blood-brain barrier includes obtaining a Raman spectrum of a selected portion of the eye and monitoring the Raman spectrum to ascertain a change to the dynamics of the blood brain barrier.Also, non-invasive methods for determining the brain or blood level of an analyte of interest, such as glucose, drugs, alcohol, poisons, and the like, comprises: generating an excitation laser beam at a selected wavelength (e.g., at a wavelength of about 400 to 900 nanometers); focusing the excitation laser beam into the anterior chamber of an eye of the subject so that aqueous humor, vitreous humor, or one or more conjunctiva vessels in the eye is illuminated; detecting (preferably confocally detecting) a Raman spectrum from the illuminated portion of the eye; and then determining the blood level or brain level (intracranial or cerebral spinal fluid level) of an analyte of interest for the subject from the Raman spectrum. In certain embodiments, the detecting step may be followed by the step of subtracting a confounding fluorescence spectrum from the Raman spectrum to produce a difference spectrum; and determining the blood level and/or brain level of the analyte of interest for the subject from that difference spectrum, preferably using linear or nonlinear multivariate analysis such as partial least squares analysis. Apparatus for carrying out the foregoing methods are also disclosed.

  10. Determination of dimethyl trisulfide in rabbit blood using stir bar sorptive extraction gas chromatography-mass spectrometry.

    PubMed

    Manandhar, Erica; Maslamani, Nujud; Petrikovics, Ilona; Rockwood, Gary A; Logue, Brian A

    2016-08-26

    Cyanide poisoning by accidental or intentional exposure poses a severe health risk. The current Food and Drug Administration approved antidotes for cyanide poisoning can be effective, but each suffers from specific major limitations concerning large effective dosage, delayed onset of action, or dependence on enzymes generally confined to specific organs. Dimethyl trisulfide (DMTS), a sulfur donor that detoxifies cyanide by converting it into thiocyanate (a relatively nontoxic cyanide metabolite), is a promising next generation cyanide antidote. Although a validated analytical method to analyze DMTS from any matrix is not currently available, one will be vital for the approval of DMTS as a therapeutic agent against cyanide poisoning. Hence, a stir bar sorptive extraction (SBSE) gas chromatography - mass spectrometry (GC-MS) method was developed and validated for the analysis of DMTS from rabbit whole blood. Following acid denaturation of blood, DMTS was extracted into a polydimethylsiloxane-coated stir bar. The DMTS was then thermally desorbed from the stir bar and analyzed by GC-MS. The limit of detection of DMTS using this method was 0.06μM with dynamic range from 0.5-100μM. For quality control standards, the precision, as measured by percent relative standard deviation, was below 10%, and the accuracy was within 15% of the nominal concentration. The method described here will allow further investigations of DMTS as a promising antidote for cyanide poisoning. PMID:27477518

  11. The Search for Water and Other Volatiles in Martian Surface Materials: The Thermal Evolved Gas Analyzer (TEGA)

    NASA Technical Reports Server (NTRS)

    Ming, D. W.; Boynton, W. V.; Musselwhite, D. S.; Bailey, S. H.; Bode, R. C.; Quadlander, G.; Kerry, K. E.; Ward, M. G.; Lorenz, R. D.; Pathare, A. V.

    2000-01-01

    Volatile-bearing minerals and phases (e.g., Fe-oxyhydroxides, phyllosilicates, carbonates, sulfates, palagonites, glasses) may be important components of the Martian regolith. However, essentially no information exists on the mineralogical composition of volatile-bearing phases in the regolith. The Thermal Evolved Gas Analyzer (TEGA), which was part of the Mars Polar Lander payload, was to determine the abundances of two of the most important volatile compounds (i.e., water and carbon dioxide) in the martian soil and to identify the minerals or phases that harbor these volatiles. The TEGA instrument was composed of a differential scanning calorimeter (DSC) interfaced with evolved gas analysis (EGA). The EGA consisted of a Herriott cell of a tunable-diode laser (TDL) spectrometer that determines CO2 and H2O abundances. The sample chamber was to operate at about 100 mbar (-76 torr) with a N2 carrier gas flow of 0.4 sccm. Specifications of TEGA are described in detail elsewhere in this volume.

  12. Analyzer for measurement of nitrogen oxide concentration by ozone content reduction in gas using solid state chemiluminescent sensor

    NASA Astrophysics Data System (ADS)

    Chelibanov, V. P.; Ishanin, G. G.; Isaev, L. N.

    2014-05-01

    Role of nitrogen oxide in ambient air is described and analyzed. New method of nitrogen oxide concentration measurement in gas phase is suggested based on ozone concentration measurement with titration by nitrogen oxide. Research of chemiluminescent sensor composition is carried out on experimental stand. The sensor produced on the base of solid state non-activated chemiluminescent composition is applied as ozone sensor. Composition is put on the surface of polymer matrix with developed surface. Sensor compositions includes gallic acid with addition of rodamine-6G. Model of interaction process between sensor composition and ozone has been developed, main products appeared during reaction are identified. The product determining the speed of luminescense appearance is found. This product belongs to quinone class. Then new structure of chemiluminescent composition was suggested, with absence of activation period and with high stability of operation. Experimental model of gas analyzer was constructed and operation algorithm was developed. It was demonstrated that developed NO measuring instrument would be applied for monitoring purposes of ambient air. This work was partially financially supported by Government of Russian Federation, Grant 074-U01

  13. Evolution of bubbles from gas micronuclei formed on the luminal aspect of ovine large blood vessels.

    PubMed

    Arieli, R; Marmur, A

    2013-08-01

    It has been shown that tiny gas nanobubbles form spontaneously on a smooth hydrophobic surface submerged in water. These nanobubbles were shown to be the source of gas micronuclei from which bubbles evolved during decompression of silicon wafers. We suggest that the hydrophobic inner surface of blood vessels may be a site of nanobubble production. Sections from the right and left atria, pulmonary artery and vein, aorta, and superior vena cava of sheep (n=6) were gently stretched on microscope slides and exposed to 1013 kPa for 18 h. Hydrophobicity was checked in the six blood vessels by advancing contact angle with a drop of saline of 71±19°, with a maximum of about 110±7° (mean±SD). Tiny bubbles ~30 μm in diameter rose vertically from the blood vessels and grew on the surface of the saline, where they were photographed. All of the blood vessels produced bubbles over a period of 80 min. The number of bubbles produced from a square cm was: in the aorta, 20.5; left atrium, 27.3; pulmonary artery, 17.9; pulmonary vein, 24.3; right atrium, 29.5; superior vena cava, 36.4. More than half of the bubbles were present for less than 2 min, but some remained on the saline-air interface for as long as 18 min. Nucleation was evident in both the venous (superior vena cava, pulmonary artery, right atrium) and arterial (aorta, pulmonary vein, left atrium) blood vessels. This newly suggested mechanism of nucleation may be the main mechanism underlying bubble formation on decompression. PMID:23624230

  14. Effects of crystalline menthol on blood metabolites in Holstein steers and in vitro volatile fatty acid and gas production.

    PubMed

    Van Bibber-Krueger, C L; Miller, K A; Aperce, C C; Alvarado-Gilis, C A; Higgins, J J; Drouillard, J S

    2016-03-01

    Fifty-two Holstein steers (573 ± 9.92 kg BW) were used to determine if oral administration of crystalline menthol would induce changes in endogenous secretions of IGF-1 and circulating concentrations of glucose, lactate, and plasma urea nitrogen (PUN). Steers were blocked by BW and assigned within block to treatment. Treatments consisted of 0, 0.003, 0.03, or 0.3% crystalline menthol (DM basis) added to the diet. Animals were housed in individual, partially covered pens equipped with feed bunks and automatic water fountains. On d 1 of the experiment, blood samples were obtained via jugular venipuncture at 0, 6, 12, 18, and 24 h after feeding. Treatment administration commenced on d 2, and blood samples were again drawn at 0, 6, 12, 18, and 24 h after feeding. This blood-sampling schedule was repeated on d 9, 16, 23, and 30. Plasma was analyzed for PUN, glucose, and lactate concentrations. Serum was used to analyze IGF-1 concentration. Body weights were measured on d 1, 9, 16, 23, and 30. To accompany the live animal phase, in vitro fermentations were performed using ruminal fluid cultures. Measurements included VFA concentrations and fermentative gas production for cultures containing crystalline menthol at 0, 0.003, 0.03, or 0.3% of substrate DM. Addition of menthol to the diet of steers resulted in a treatment × day interaction ( < 0.01) for concentrations of IGF-1, PUN, and plasma glucose. Cattle fed 0 and 0.003% menthol had greater serum IGF-1 concentrations on d 2 compared with steers fed 0.03% menthol. Steers fed 0% menthol had greater serum IGF-1 concentrations on d 9 compared with steers fed 0.03 and 0.3% menthol, whereas no differences were observed on d 23 or 30. Plasma glucose was similar among treatments until d 23, when steers supplemented with 0.03% menthol had lower glucose concentrations. Plasma urea nitrogen concentrations were not different among treatments; however, PUN concentrations varied by day. A linear response was detected for BW ( = 0

  15. Dependence of phrenic motoneurone output on the oscillatory component of arterial blood gas composition.

    PubMed Central

    Cross, B A; Grant, B J; Guz, A; Jones, P W; Semple, S J; Stidwill, R P

    1979-01-01

    1. The hypothesis that respiratory oscillations of arterial blood gas composition influence ventilation has been examined. 2. Phrenic motoneurone output recorded in the C5 root of the left phrenic nerve and the respiratory oscillations of arterial pH in the right common carotid artery were measured in vagotomized anaesthetized dogs which had been paralysed and artificially ventilated. 3. The effect of a change in tidal volume for one or two breaths on phrenic motoneurone output was measured with the inspiratory pump set at a constant frequency similar to, and in phase with, the animal's own respiratory frequency. A reduction of tidal volume to zero or an increase by 30% led to a corresponding change of mean carotid artery pH level. The changes of carotid artery pH resulted in a change of phrenic motoneurone output, predominantly of expiratory time (Te) but to a lesser extent of inspiratory time (T1) and also peak amplitude of 'integrated' phrenic motoneurone output (Phr). Denervation of the carotid bifurcation blocked this response. 4. The onset of movement of the inspiratory pump was triggered by the onset of phrenic motoneurone output. When a time delay was interposed between them, the phase relationship between respiratory oscillations of arterial pH and phrenic motoneurone output altered. The dominant effect was to alter Te; smaller and less consistent changes of Phr and T1 were observed. 5. When the inspiratory pump was maintained at a constant frequency but independent of and slightly different from the animal's own respiratory frequency (as judged by phrenic motoneurone output), the phase relationship between phrenic motoneurone output and the respiratory oscillations of pH changed breath by breath over a sequence of 100-200 breaths, without change of the mean level of arterial blood gas composition. Te varied by up to 30% about its mean value depending on the phase relationship. Ti and Phr were also dependent on the phase relationship but varied to a lesser

  16. Comparing laser-based open- and closed-path gas analyzers to measure methane fluxes using the eddy covariance method

    USGS Publications Warehouse

    Detto, M.; Verfaillie, J.; Anderson, F.; Xu, L.; Baldocchi, D.

    2011-01-01

    Closed- and open-path methane gas analyzers are used in eddy covariance systems to compare three potential methane emitting ecosystems in the Sacramento-San Joaquin Delta (CA, USA): a rice field, a peatland pasture and a restored wetland. The study points out similarities and differences of the systems in field experiments and data processing. The closed-path system, despite a less intrusive placement with the sonic anemometer, required more care and power. In contrast, the open-path system appears more versatile for a remote and unattended experimental site. Overall, the two systems have comparable minimum detectable limits, but synchronization between wind speed and methane data, air density corrections and spectral losses have different impacts on the computed flux covariances. For the closed-path analyzer, air density effects are less important, but the synchronization and spectral losses may represent a problem when fluxes are small or when an undersized pump is used. For the open-path analyzer air density corrections are greater, due to spectroscopy effects and the classic Webb-Pearman-Leuning correction. Comparison between the 30-min fluxes reveals good agreement in terms of magnitudes between open-path and closed-path flux systems. However, the scatter is large, as consequence of the intensive data processing which both systems require. ?? 2011.

  17. Temperature, density, and composition in the disturbed thermosphere from Esro 4 gas analyzer measurements - A global model

    NASA Technical Reports Server (NTRS)

    Jacchia, L. G.; Slowey, J. W.; Von Zahn, U.

    1977-01-01

    An analysis of density measurements of Ar, N2, O, and He made at 280 km with the gas analyzer aboard the polar-orbiting satellite Esro 4 has yielded a global model of the variations in temperature, density, and composition that occur in the disturbed thermosphere. In the model the increase of temperature over quiet conditions is a nonlinear function of the planetary geomagnetic index, its latitude profile being approximated by a fourth-power sin phi law, where phi is the 'invariant' magnetic latitude. A density wave proceeding from high latitudes is approximated by a fourth power cos phi law. A strong nonlinearity in the relation between the temperature variations and the variations in the height of the homopause explains a previously found behavioral difference in the variation of atomic oxygen during magnetic storms and during periods of sustained geomagnetic activity.

  18. Analyzing the kinetic response of tin oxide-carbon and tin oxide-CNT composites gas sensors for alcohols detection

    NASA Astrophysics Data System (ADS)

    Kamble, Vinayak; Umarji, Arun

    2015-03-01

    Tin oxide nanoparticles are synthesized using solution combustion technique and tin oxide - carbon composite thick films are fabricated with amorphous carbon as well as carbon nanotubes (CNTs). The x-ray diffraction, Raman spectroscopy and porosity measurements show that the as-synthesized nanoparticles are having rutile phase with average crystallite size ˜7 nm and ˜95 m2/g surface area. The difference between morphologies of the carbon doped and CNT doped SnO2 thick films, are characterized using scanning electron microscopy and transmission electron microscopy. The adsorption-desorption kinetics and transient response curves are analyzed using Langmuir isotherm curve fittings and modeled using power law of semiconductor gas sensors.

  19. Analyzing the kinetic response of tin oxide-carbon and tin oxide-CNT composites gas sensors for alcohols detection

    SciTech Connect

    Kamble, Vinayak Umarji, Arun

    2015-03-15

    Tin oxide nanoparticles are synthesized using solution combustion technique and tin oxide – carbon composite thick films are fabricated with amorphous carbon as well as carbon nanotubes (CNTs). The x-ray diffraction, Raman spectroscopy and porosity measurements show that the as-synthesized nanoparticles are having rutile phase with average crystallite size ∼7 nm and ∼95 m{sup 2}/g surface area. The difference between morphologies of the carbon doped and CNT doped SnO{sub 2} thick films, are characterized using scanning electron microscopy and transmission electron microscopy. The adsorption-desorption kinetics and transient response curves are analyzed using Langmuir isotherm curve fittings and modeled using power law of semiconductor gas sensors.

  20. The usefulness of the arterial blood gas in pure carbon monoxide poisoning.

    PubMed

    Lebby, T I; Zalenski, R; Hryhorczuk, D O; Leikin, J B

    1989-04-01

    In a retrospective study of 49 cases of carbon monoxide (CO) intoxication presented to the University of Illinois Hospital (UIH) Emergency Department between November 1986 and April 1988, we looked for a correlation between carboxyhemoglobin (COHb) as determined by a venous sample and the pH as determined by arterial blood gas analysis. The range of COHb levels in our study was 10-64% (mean 21.8% +/- 10.2%). Smoke inhalation cases (n = 3) were excluded from our study because they did not represent pure CO intoxication. Of the remaining 46 cases, 18 had arterial blood gases drawn. In none of these 18 cases (mean COHb 24.5% +/- 12.6%) did we find a correlation between COHb levels and the pH as determined by linear regression analysis. Also, in none of the 18 cases were there any therapeutic interventions associated with the arterial blood gas result. Additionally, in none of the remaining 28 cases were any therapeutic interventions performed with regards to patients' acidosis or ventilatory status (except 100% oxygen administration. We also retrospectively reviewed records of 104 cases who presented to Cook County Hospital Emergency Department with COHb levels over 10% during the period between March 1986 and May 1988. In these cases, we found no significant correlation between COHb level and arterial pH. We therefore conclude that arterial blood gases drawn in order to determine the degree of acidosis in mild CO intoxication without respiratory distress may not be useful in guiding therapeutic intervention and need not be routinely drawn. PMID:2929122

  1. Use of dissociative anesthetics for the immobilization of captive bears: blood gas, hematology and biochemistry values.

    PubMed

    Bush, M; Custer, R S; Smith, E E

    1980-10-01

    Nineteen bears, representing five species (Helarctos malayanus, Ursus americanus, Ursus arctos, Tremarctos ornatus, Melursus ursinus) were immobilized a total of 52 times using either phencyclidine-promazine or tiletamine-zolazepam. Blood gas, hematology, and serum biochemistry values were determined during the immobilizations. Immobilizations conducted with tiletamine-zolazepam were characterized by rapid induction and recovery times, good muscle relaxation, and relative freedom from convulsions. Bears immobilized with phencyclidine-promazine had longer induction and recovery times and showed convulsive activity in 29% of the trials with that combination. PMID:7463600

  2. Effects of ambient air particulate exposure on blood-gas barrier permeability and lung function.

    PubMed

    Bräuner, Elvira Vaclavik; Mortensen, Jann; Møller, Peter; Bernard, Alfred; Vinzents, Peter; Wåhlin, Peter; Glasius, Marianne; Loft, Steffen

    2009-01-01

    Particulate air pollution is associated with increased risk of pulmonary diseases and detrimental outcomes related to the cardiovascular system, including altered vessel functions. This study's objective was too evaluate the effects of ambient particle exposure on the blood-gas permeability, lung function and Clara cell 16 (CC16) protein release in healthy young subjects. Twenty-nine nonsmokers participated in a randomized, two-factor crossover study with or without biking exercise for 180 min and with 24-h exposure to particle-rich (6169-15,362 particles/cm(3); 7.0-11.6 microg/m(3) PM(2.5); 7.5-15.8 microg/m(3) PM(10-2.5)) or filtered (91-542 particles/cm(3)) air collected above a busy street. The clearance rate of aerosolized (99m)Tc-labeled diethylenetriamine pentaacetic acid ((99m)Tc-DTPA) was measured as an index for the alveolar epithelial membrane integrity and permeability of the lung blood-gas barrier after rush-hour exposure. Lung function was assessed using body plethysmography, flow-volume curves, and measurements of the diffusion capacity of carbon monoxide. CC16 was measured in plasma and urine as another marker of alveolar integrity. Particulate matter exposure had no significant effect on the epithelial membrane integrity using the methods available in this study. Exercise increased the clearance rate of (99m)Tc-DTPA indicated by a 6.8% (95% CI: 0.4-12.8%) shorter half-life and this was more pronounced in men than women. Neither particulate matter exposure nor exercise had an effect on the concentration of CC16 in plasma and urine or on the static and dynamic volumes or ventilation distribution of the lungs. The study thus demonstrates increased permeability of the alveolar blood-gas barrier following moderate exercise, whereas exposure to ambient levels of urban air particles has no detectable effects on the alveolar blood-gas barrier or lung function. PMID:18752169

  3. [Gas chromatography in quantitative analysis of hydrocyanic acid and its salts in cadaveric blood].

    PubMed

    Iablochkin, V D

    2003-01-01

    A direct gas chromatography method was designed for the quantitative determination of cyanides (prussic acid) in cadaveric blood. Its sensitivity is 0.05 mg/ml. The routine volatile products, including substances, which emerge due to putrefaction of organic matters, do not affect the accuracy and reproducibility of the method; the exception is H-propanol that was used as the internal standard. The method was used in legal chemical expertise related with acute cyanide poisoning (suicide) as well as with poisoning of products of combustion of nonmetals (foam-rubber). The absolute error does not exceed 10% with a mean quadratic deviation of 0.0029-0.0033 mg. PMID:14689782

  4. Finite-sized gas bubble motion in a blood vessel: Non-Newtonian effects

    PubMed Central

    Mukundakrishnan, Karthik; Ayyaswamy, Portonovo S.; Eckmann, David M.

    2009-01-01

    We have numerically investigated the axisymmetric motion of a finite-sized nearly occluding air bubble through a shear-thinning Casson fluid flowing in blood vessels of circular cross section. The numerical solution entails solving a two-layer fluid model—a cell-free layer and a non-Newtonian core together with the gas bubble. This problem is of interest to the field of rheology and for gas embolism studies in health sciences. The numerical method is based on a modified front-tracking method. The viscosity expression in the Casson model for blood (bulk fluid) includes the hematocrit [the volume fraction of red blood cells (RBCs)] as an explicit parameter. Three different flow Reynolds numbers, Reapp=ρlUmaxd/μapp, in the neighborhood of 0.2, 2, and 200 are investigated. Here, ρl is the density of blood, Umax is the centerline velocity of the inlet Casson profile, d is the diameter of the vessel, and μapp is the apparent viscosity of whole blood. Three different hematocrits have also been considered: 0.45, 0.4, and 0.335. The vessel sizes considered correspond to small arteries, and small and large arterioles in normal humans. The degree of bubble occlusion is characterized by the ratio of bubble to vessel radius (aspect ratio), λ, in the range 0.9≤λ≤1.05. For arteriolar flow, where relevant, the Fahraeus-Lindqvist effects are taken into account. Both horizontal and vertical vessel geometries have been investigated. Many significant insights are revealed by our study: (i) bubble motion causes large temporal and spatial gradients of shear stress at the “endothelial cell” (EC) surface lining the blood vessel wall as the bubble approaches the cell, moves over it, and passes it by; (ii) rapid reversals occur in the sign of the shear stress (+ → − → +) imparted to the cell surface during bubble motion; (iii) large shear stress gradients together with sign reversals are ascribable to the development of a recirculation vortex at the rear of the bubble

  5. Finite-sized gas bubble motion in a blood vessel: Non-Newtonian effects

    NASA Astrophysics Data System (ADS)

    Mukundakrishnan, Karthik; Ayyaswamy, Portonovo S.; Eckmann, David M.

    2008-09-01

    We have numerically investigated the axisymmetric motion of a finite-sized nearly occluding air bubble through a shear-thinning Casson fluid flowing in blood vessels of circular cross section. The numerical solution entails solving a two-layer fluid model—a cell-free layer and a non-Newtonian core together with the gas bubble. This problem is of interest to the field of rheology and for gas embolism studies in health sciences. The numerical method is based on a modified front-tracking method. The viscosity expression in the Casson model for blood (bulk fluid) includes the hematocrit [the volume fraction of red blood cells (RBCs)] as an explicit parameter. Three different flow Reynolds numbers, Reapp=ρlUmaxd/μapp , in the neighborhood of 0.2, 2, and 200 are investigated. Here, ρl is the density of blood, Umax is the centerline velocity of the inlet Casson profile, d is the diameter of the vessel, and μapp is the apparent viscosity of whole blood. Three different hematocrits have also been considered: 0.45, 0.4, and 0.335. The vessel sizes considered correspond to small arteries, and small and large arterioles in normal humans. The degree of bubble occlusion is characterized by the ratio of bubble to vessel radius (aspect ratio), λ , in the range 0.9⩽λ⩽1.05 . For arteriolar flow, where relevant, the Fahraeus-Lindqvist effects are taken into account. Both horizontal and vertical vessel geometries have been investigated. Many significant insights are revealed by our study: (i) bubble motion causes large temporal and spatial gradients of shear stress at the “endothelial cell” (EC) surface lining the blood vessel wall as the bubble approaches the cell, moves over it, and passes it by; (ii) rapid reversals occur in the sign of the shear stress (+ → - → +) imparted to the cell surface during bubble motion; (iii) large shear stress gradients together with sign reversals are ascribable to the development of a recirculation vortex at the rear of the bubble

  6. Comparison of gas clearance and radioactive microspheres for pancreatic blood flow measurement

    SciTech Connect

    DeMar, A.R.; Graham, L.S.; Lake, R.; Fink, A.S. )

    1989-01-01

    Measurement of pancreatic blood flow (PBF) is technically demanding. Although radiolabeled microspheres are considered the gold standard for PBF assessment, they have practical limitations. In the current study, H{sub 2} and xenon-133 gas clearance techniques were adapted to PBF measurement and compared to radiolabeled microsphere techniques. Simultaneous measurements of PBF were made using either hydrogen or xenon gas washout and radiolabeled microspheres. Measurements were made under basal, vasoconstricted (vasopressin 2U i.v. or nicotine 4 micrograms/kg/h) and stimulated (secretin 125 ng/kg/h or 2 U/kg i.v.) conditions (random order). Mean PBF was 26.9 +/- 5.3, 50.5 +/- 2.3 and 27.6 +/- 5.2 ml/min/100 g basally, 36.9 +/- 8.0, 90.1 +/- 18.9, and 81.7 +/- 14.5 ml/min/100 g in the stimulated state, and 24.2 +/- 7.8, 25.0 +/- 3.5, and 14.9 +/- 7.5 ml/min/100 g in the vasoconstricted state for hydrogen gas clearance, xenon gas clearance, and radiolabeled microspheres, respectively. The H{sub 2} clearance technique resulted in tissue trauma, was complicated by frequent electrode displacement, and correlated poorly (r2 = 0.36, p greater than 0.05) with microsphere values. In contrast, xenon clearance measurement had no apparent effect on the pancreas and correlated well (r2 = 0.83, p less than 0.01) with microsphere data. We conclude that xenon clearance offers an attractive, validated alternative to radiolabeled microspheres for measuring pancreatic blood flow.

  7. Measurements of Flow Distortion within the IRGASON Integrated Sonic Anemometer and CO_2 /H_2 O Gas Analyzer

    NASA Astrophysics Data System (ADS)

    Horst, T. W.; Vogt, R.; Oncley, S. P.

    2016-02-01

    Wind-tunnel and field measurements are analyzed to investigate flow distortion within the IRGASON integrated sonic anemometer and CO_2 /H_2 O gas analyzer as a function of wind speed, wind direction and attack angle. The wind-tunnel measurements are complimentary to the field measurements, and the dependence of the wind-tunnel mean-wind-component flow-distortion errors on wind direction agrees well with that of the field measurements. The field measurements exhibit significant overestimation of the crosswind variance and underestimation of the momentum flux with respect to an adjacent CSAT3 sonic, as well as a transfer of turbulent kinetic energy from the streamwise wind component to the cross-stream wind components. In contrast, we find attenuation of only a few percent in the vertical velocity variance and the vertical flux of sonic temperature. The attenuation of the fluxes appears to be caused to a large extent by decorrelation between the horizontal and vertical-velocity components and between the vertical velocity and sonic temperature. Additional flow distortion due to transducer shadowing reduces to some extent the overestimation, but also increases the underestimation of the IRGASON turbulence statistics.

  8. Measurements of Flow Distortion within the IRGASON Integrated Sonic Anemometer and CO_2/H_2O Gas Analyzer

    NASA Astrophysics Data System (ADS)

    Horst, T. W.; Vogt, R.; Oncley, S. P.

    2016-07-01

    Wind-tunnel and field measurements are analyzed to investigate flow distortion within the IRGASON integrated sonic anemometer and CO_2/H_2O gas analyzer as a function of wind speed, wind direction and attack angle. The wind-tunnel measurements are complimentary to the field measurements, and the dependence of the wind-tunnel mean-wind-component flow-distortion errors on wind direction agrees well with that of the field measurements. The field measurements exhibit significant overestimation of the crosswind variance and underestimation of the momentum flux with respect to an adjacent CSAT3 sonic, as well as a transfer of turbulent kinetic energy from the streamwise wind component to the cross-stream wind components. In contrast, we find attenuation of only a few percent in the vertical velocity variance and the vertical flux of sonic temperature. The attenuation of the fluxes appears to be caused to a large extent by decorrelation between the horizontal and vertical-velocity components and between the vertical velocity and sonic temperature. Additional flow distortion due to transducer shadowing reduces to some extent the overestimation, but also increases the underestimation of the IRGASON turbulence statistics.

  9. Impact of Gas Delivery Systems on Imaging Studies of Human Cerebral Blood Flow

    PubMed Central

    Cain, John R.; Parkes, Laura M.; Eadsforth, Peter; Beards, Susan C.; Jackson, Alan

    2013-01-01

    Purpose. To compare a semiopen breathing circuit with a non-rebreathing (Hudson mask) for MRI experiments involving gas delivery. Methods and Materials. Cerebral blood flow (CBF) was measured by quantitative phase contrast angiography of the internal carotid and basilar arteries in 18 volunteers (20–31 years). In 8 subjects, gases were delivered via a standard non-rebreathing (Hudson mask). In 10 subjects, gases were delivered using a modified “Mapleson A” semiopen anesthetic gas circuit and mouthpiece. All subjects were given 100% O2, medical air, and carbogen gas (95% O2 and 5% CO2) delivered at 15 L/min in a random order. Results. The Hudson mask group showed significant increases in CBF in response to increased FiCO2 compared to air (+9.8%). A small nonsignificant reduction in CBF (−2.4%) was seen in response to increased inspired concentrations of oxygen (FiO2). The Mapleson A group showed significantly larger changes in CBF in response to both increased inspired concentrations of carbon dioxide (FiCO2) (+32.2%, P < 0.05) and FiO2 (−14.6%, P < 0.01). Conclusions. The use of an anaesthetic gas delivery circuit avoids entrainment of room air and rebreathing effects that may otherwise adversely affect the experimental results. PMID:24392225

  10. Impact of gas delivery systems on imaging studies of human cerebral blood flow.

    PubMed

    Cain, John R; Parkes, Laura M; Eadsforth, Peter; Beards, Susan C; Jackson, Alan

    2013-01-01

    Purpose. To compare a semiopen breathing circuit with a non-rebreathing (Hudson mask) for MRI experiments involving gas delivery. Methods and Materials. Cerebral blood flow (CBF) was measured by quantitative phase contrast angiography of the internal carotid and basilar arteries in 18 volunteers (20-31 years). In 8 subjects, gases were delivered via a standard non-rebreathing (Hudson mask). In 10 subjects, gases were delivered using a modified "Mapleson A" semiopen anesthetic gas circuit and mouthpiece. All subjects were given 100% O2, medical air, and carbogen gas (95% O2 and 5% CO2) delivered at 15 L/min in a random order. Results. The Hudson mask group showed significant increases in CBF in response to increased FiCO2 compared to air (+9.8%). A small nonsignificant reduction in CBF (-2.4%) was seen in response to increased inspired concentrations of oxygen (FiO2). The Mapleson A group showed significantly larger changes in CBF in response to both increased inspired concentrations of carbon dioxide (FiCO2) (+32.2%, P < 0.05) and FiO2 (-14.6%, P < 0.01). Conclusions. The use of an anaesthetic gas delivery circuit avoids entrainment of room air and rebreathing effects that may otherwise adversely affect the experimental results. PMID:24392225

  11. Method for extending the useful shelf-life of refrigerated red blood cells by flushing with inert gas

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1997-04-29

    A method is disclosed using oxygen removal for extending the useful shelf-life of refrigerated red blood cells. A cost-effective, 4 C storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. Preservation of adenosine triphosphate levels and reduction in hemolysis and in membrane vesicle production of red blood cells stored at 4 C for prolonged periods of time is achieved by removing oxygen from the red blood cells at the time of storage; in particular, by flushing with an inert gas. Adenosine triphosphate levels of the stored red blood cells are boosted in some samples by addition of ammonium phosphate. 4 figs.

  12. Blood gas stability and hematological changes in experimentally-induced acute porcine pleuropneumonia.

    PubMed Central

    Kiorpes, A L; Mirsky, M L; MacWilliams, P S; Bäckström, L R; Collins, M T

    1989-01-01

    Blood gas and hematological responses to acute, mild Actinobacillus pleuropneumoniae infection of growing pigs was studied. Six pigs (average weight 10.1 kg) were experimentally infected intranasally with A. pleuropneumoniae serotype 5. Four pigs served as controls. Rectal temperatures and arterial blood for gas analysis and hematology were taken at 0, 8, 16, 24, 48 and 72 h postinfection. All infected pigs became febrile showing clinical signs typical of mild to moderate porcine pleuropneumonia; controls remained asymptomatic. Neutrophilia with bands and lymphopenia were observed only in infected pigs. Arterial partial pressures of O2 and CO2, and pH did not change in infected pigs. All pigs were killed after 72 h, and lungs were examined and cultured. Gross and microscopic lesions consistent with porcine pleuropneumonia were seen in 3/6 and 5/6 infected lungs, respectively. Control lungs were grossly normal with no histological evidence of pleuropneumonia. We conclude that in mild, acute porcine pleuropneumonia as established experimentally, a leukogram typical of acute inflammation and stress is seen; however, hypoxemia and alveolar hypoventilation are not features of this form of the disease. PMID:2914231

  13. Earlobe arterialized capillary blood gas analysis in the intensive care unit: a pilot study

    PubMed Central

    2014-01-01

    Background Earlobe arterialized capillary blood gas analysis can be used to estimate arterial gas content and may be suitable for diagnosis and management of critically ill patients. However, its utility and applicability in the ICU setting remains unexplored. Methods A prospective observational validation study was designed to evaluate this technique in a cohort of mechanically ventilated adult critically ill patients admitted to a polyvalent ICU. Precision and agreement between capillary gas measures and arterial references was examined. Acute Respiratory Distress Syndrome (ARDS) diagnosis capabilities with the proposed technique were also evaluated. Finally, factors associated with sampling failure were explored. Results Fifty-five patients were included into this study. Precision of capillary samples was high (Coefficient of Variation PO2 = 9.8%, PCO2 = 7.7%, pH = 0.3%). PO2 measures showed insufficient agreement levels (Concordance Correlation Coefficient = 0.45; bias = 12 mmHg; percentage of error = 19.3%), whereas better agreement was observed for PCO2 and pH (Concordance Correlation Coefficient = 0.94 and 0.93 respectively; depreciable bias; percentage of error 11.4% and 0.5% respectively). The sensitivity and specificity for diagnosing ARDS were 100% and 92.3% using capillary gasometric measures. Sampling was unsuccessful in 43.6% of cases due to insufficient blood flow. Age > 65 years was independently associated with failure (odds ratio = 1.6), however hemodynamic failure and norepinephrine treatment were also influencing factors. Conclusions Earlobe capillary blood gas analysis is precise and can be useful for detecting extreme gasometrical values. Diagnosis of ARDS can be done accurately using capillary measurements. Although this technique may be insufficient for precise management of patients in the ICU, it has the potential for important benefits in the acute phase of various critical conditions and in other

  14. [Blood gas changes during treadmill exercise in convalescents from pulmonary tuberculosis. 1. Method of measurement].

    PubMed

    Yoshida, F

    1989-09-01

    With advances in treatment for tuberculosis, pulmonary tuberculosis has become curable. However, chronic respiratory failure has been more often observed in those who have ever had thoracic operation, and were cured with anti-tuberculous chemotherapy in spite of initially severe pulmonary tuberculosis with wide spread lesions in both lungs, particularly in the aged. Therefore it is now necessary to understand accurately the real physio-dynamic situation of respiro-circulatory impairment in these patients. For this purpose, an exercise test was newly designed, and changing curves of blood gas (O2- and CO2-partial pressure, measured transcutaneously) were drawn in 4 healthy persons and 23 recovered patients from pulmonary tuberculosis. The newly designed method was carried out by using Treadmill walk apparatus (Nihon-Denki Sanei Co., Japan), transcutaneous blood gas measurement apparatus (Radio-Meter Co., Copenhagen) and automatic blood pressure measurement apparatus (Kyorin Co., Japan). Treadmill walk exercise test was done through Bruce-Sheffield converted method. The details of this exercise test are written and illustrated in this paper. The results of the test were classified into 4 types by the changes of transcutaneously measured O2 partial pressure curve during the test: 1. unchanged, 2. slightly decreased, 3. moderately decreased, 4. markedly decreased. The significance of these 4 types will be discussed in the next report after examining more convalescents from pulmonary tuberculosis. The reproducibility of this test was examined in 6 patients, and it was almost good. In addition, in 3 out of 27 patients, odd curves contrary to our expectation, that is increase of the value of trans-cutaneously measured O2 partial pressure and/or decrease of the value of trans-cutaneously measured CO2 partial pressure immediately after the initiation of the first test were observed. But in the second test, carried out in the other day, the curve fell into one of the 4 types

  15. Sample Processing technique onboard ExoMars (MOMA) to analyze organic compounds by Gas Chromatography-Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Buch, A.; Freissinet, C.; Sternberg, R.; Szopa, C.; Coll, P. J.; Brault, A.; Pinnick, V.; Siljeström, S.; Raulin, F.; Steininger, H.; Goesmann, F.; MOMA Team

    2011-12-01

    With the aim of separating and detecting organic compounds from Martian soil onboard the Mars Organic Molecule Analyzer (MOMA) experiment of the ExoMars 2018 upcoming joint ESA/NASA mission, we have developed three different space compatible sample preparation techniques compatible with space missions, able to extract and analyze by GC-MS a wide range of volatile and refractory compounds, including chirality analysis. Then, a sample processing utilizing three derivatization/extraction reactions has been carried out. The first reaction is based on a silyl reagent N-Methyl-N- (Tert-Butyldimethylsilyl)trifluoroacetamide (MTBSTFA) [1], the second one, N,N-Dimethylformamide Dimethylacetal (DMF-DMA) [2,3] is dedicated to the chirality detection and the third one is a thermochemolysis based on the use of tetramethylammoniumhydroxide (TMAH). The sample processing system is performed in an oven, dedicated to the MOMA experiment containing the solid sample (50-100mg). The internal temperature of the oven ranges from 20 to 900 °C. The extraction step is achieved by using thermodesorption in the range of 100 to 300°C for 5 to 20 min. Then, the chemical derivatization of the extracted compounds is performed directly on the soil sample by using a derivatyization capsule which contains a mixture of MTBSTFA-DMF or DMF-DMA solution when enantiomeric separation is required. By decreasing the polarity of the targeted molecules, this step allows their volatilization at a temperature below 250°C without any thermal degradation. Once derivatized, the volatile target molecules are trapped in a chemical trap and promptly desorbed into the gas chromatograph coupled to a mass spectrometer. Thermochemolysis is directly performed in the oven at 400°C during 5 min with a 25% (w/w) methanol solution of tetramethylammonium hydroxide (TMAH). Then, pyrolysis in the presence of TMAH allows both an efficient cleavage of polar bonds and the subsequent methylation of COOH, OH and NH2 groups, hence

  16. Statistical modelling of measurement errors in gas chromatographic analyses of blood alcohol content.

    PubMed

    Moroni, Rossana; Blomstedt, Paul; Wilhelm, Lars; Reinikainen, Tapani; Sippola, Erkki; Corander, Jukka

    2010-10-10

    Headspace gas chromatographic measurements of ethanol content in blood specimens from suspect drunk drivers are routinely carried out in forensic laboratories. In the widely established standard statistical framework, measurement errors in such data are represented by Gaussian distributions for the population of blood specimens at any given level of ethanol content. It is known that the variance of measurement errors increases as a function of the level of ethanol content and the standard statistical approach addresses this issue by replacing the unknown population variances by estimates derived from large sample using a linear regression model. Appropriate statistical analysis of the systematic and random components in the measurement errors is necessary in order to guarantee legally sound security corrections reported to the police authority. Here we address this issue by developing a novel statistical approach that takes into account any potential non-linearity in the relationship between the level of ethanol content and the variability of measurement errors. Our method is based on standard non-parametric kernel techniques for density estimation using a large database of laboratory measurements for blood specimens. Furthermore, we address also the issue of systematic errors in the measurement process by a statistical model that incorporates the sign of the error term in the security correction calculations. Analysis of a set of certified reference materials (CRMs) blood samples demonstrates the importance of explicitly handling the direction of the systematic errors in establishing the statistical uncertainty about the true level of ethanol content. Use of our statistical framework to aid quality control in the laboratory is also discussed. PMID:20494532

  17. Continuous arterial blood gas monitoring in rabbits: an efficient method for evaluation of ratio-based optrodes

    NASA Astrophysics Data System (ADS)

    Martin, Roy C.; Olstein, Alan D.; Malin, Stephen F.; Perkovich, Anne

    1992-04-01

    Laboratory bench testing of optical blood gas sensors is insufficient to completely predict capabilities. Sensor testing in animals offers advantages of known physiologic and regulatory mechanisms of hemodynamics to better predict sensor performance. The domestic rabbit, Oryctalogis Cuniculus, a lagomorph of the family Leporidae was used for sensor evaluation. The rabbits are ventilated and blood gases modulated by variations in FIO2 and rate adjustments. Twenty gauge catheters are placed in the dorsal aorta, cartoid, and femoral arteries. Pressures are monitored via transducers on the arterial lines. The optical blood gas sensors are fitted within the catheters and blood samples are collected over them for bench analysis. Sensors are on 125 micrometers glass optic fibers. Proprietary prepolymers are applied on the fiber tips through in fiber photopolymerization. These sensors are then calibrated in tonometered water and blood. Sensor monitoring is accomplished through OSR microfluorimetry systems. We have used this model in 26 studies over the past six months evaluating over fifty blood gas sensors. These studies have lasted from six to twenty-four hours. Our correlation of sensor readings to assayed blood samples is r2 equals .97 for pH values of 6.80 - 7.70, r2 equals .94 for PCO2 values of 10 - 175 mmHg and r2 equals .94 for PO2 values of 10 - 350 mmHg.

  18. Comparative physiology of the pulmonary blood-gas barrier: the unique avian solution

    PubMed Central

    2009-01-01

    Two opposing selective pressures have shaped the evolution of the structure of the blood-gas barrier in air breathing vertebrates. The first pressure, which has been recognized for 100 years, is to facilitate diffusive gas exchange. This requires the barrier to be extremely thin and have a large area. The second pressure, which has only recently been appreciated, is to maintain the mechanical integrity of the barrier in the face of its extreme thinness. The most important tensile stress comes from the pressure within the pulmonary capillaries, which results in a hoop stress. The strength of the barrier can be attributed to the type IV collagen in the extracellular matrix. In addition, the stress is minimized in mammals and birds by complete separation of the pulmonary and systemic circulations. Remarkably, the avian barrier is about 2.5 times thinner than that in mammals and also is much more uniform in thickness. These advantages for gas exchange come about because the avian pulmonary capillaries are unique among air breathers in being mechanically supported externally in addition to the strength that comes from the structure of their walls. This external support comes from epithelial plates that are part of the air capillaries, and the support is available because the terminal air spaces in the avian lung are extremely small due to the flow-through nature of ventilation in contrast to the reciprocating pattern in mammals. PMID:19793953

  19. Determination of volatile N-nitrosamines in irradiated fermented sausage by gas chromatography coupled to a thermal energy analyzer.

    PubMed

    Byun, Myung-Woo; Ahn, Hyun-Joo; Kim, Jae-Hyun; Lee, Ju-Woon; Yook, Hong-Sun; Han, Sang-Bae

    2004-10-29

    Volatile N-nitrosodimethylamine (NDMA) and N-nitrosopyrrolidine (NPYR) in irradiated pepperoni and salami sausages were determined using a gas chromatography coupled to a thermal energy analyzer (GC-TEA). These fermented sausages with aerobic or vacuum packaging were irradiated at 0, 5, 10, and 20 kGy, and then stored for 4 weeks at 4 degrees C. Both NDMA and NPYR in the fermented sausage were significantly reduced by irradiation. The vacuum packaging showed significantly lower (P < 0.05) N-nitrosamine levels than that of the aerobic ones. After storage, the contents of NDMA and NPYR in the irradiated sausage were lower than those of the non-irradiated control. Results indicated that a high dose of irradiation (>10 kGy) was needed to reduce the carcinogenic N-nitrosamines in the fermented sausage during storage and the GC-TEA analysis was effective in determining the N-nitrosamines in irradiated meats even at low trace levels. PMID:15553169

  20. Gas analyzer's drift leads to systematic error in maximal oxygen uptake and maximal respiratory exchange ratio determination

    PubMed Central

    Garcia-Tabar, Ibai; Eclache, Jean P.; Aramendi, José F.; Gorostiaga, Esteban M.

    2015-01-01

    The aim was to examine the drift in the measurements of fractional concentration of oxygen (FO2) and carbon dioxide (FCO2) of a Nafion-using metabolic cart during incremental maximal exercise in 18 young and 12 elderly males, and to propose a way in which the drift can be corrected. The drift was verified by comparing the pre-test calibration values with the immediate post-test verification values of the calibration gases. The system demonstrated an average downscale drift (P < 0.001) in FO2 and FCO2 of −0.18% and −0.05%, respectively. Compared with measured values, corrected average maximal oxygen uptakevalues were 5–6% lower (P < 0.001) whereas corrected maximal respiratory exchange ratio values were 8–9% higher (P < 0.001). The drift was not due to an electronic instability in the analyzers because it was reverted after 20 min of recovery from the end of the exercise. The drift may be related to an incomplete removal of water vapor from the expired gas during transit through the Nafion conducting tube. These data demonstrate the importance of checking FO2 and FCO2 values by regular pre-test calibrations and post-test verifications, and also the importance of correcting a possible shift immediately after exercise. PMID:26578980

  1. EVALUATION OF CARDIORESPIRATORY, BLOOD GAS, AND LACTATE VALUES DURING EXTENDED IMMOBILIZATION OF WHITE RHINOCEROS (CERATOTHERIUM SIMUM).

    PubMed

    Buss, Peter; Olea-Popelka, Francisco; Meyer, Leith; Hofmeyr, Jennifer; Mathebula, Nomkhosi; Kruger, Marius; Brüns, Angela; Martin, Laura; Miller, Michele

    2015-06-01

    Ten white rhinoceros (Ceratotherium simum) were immobilized for a total of 13 procedures in holding facilities in Kruger National Park using etorphine, azaperone, and hyaluronidase to assess the effect of extended immobilization on serial cardiorespiratory, blood gas, and lactate values. Butorphanol was administered intravenously following initial blood collection and physiologic assessment (t=0). Respiratory and cardiovascular parameters, body temperature, and arterial blood gases were monitored at 10-min intervals for a total of 100 min. Initial parameters at the time of recumbency revealed severe hypoxemia, hypercapnia, tachycardia, an increased alveolar-arterial (A-a) gradient, and mildly elevated lactate levels. At 10 min and 20 min, there were significant (P<0.05) changes in the following physiologic parameters: heart rate decreased [96 and 80 beats/min, respectively, vs. 120 beats/min], arterial partial pressure of oxygen (PaO2) increased [48 and 45 mm Hg, respectively vs. 30 mm Hg], arterial hemoglobin oxygen saturation increased [79% and 74%, respectively, vs. 47%], A-a gradient decreased [29.13 and 30.00 mm Hg, respectively, vs. 49.19 mm Hg], and respiratory rate decreased [5 and 5 breaths/min vs. 7 breaths/min]. Blood lactate levels also decreased from 2.54 mM/L to 1.50 and 0.89 mM/L, respectively. Despite initial improvements in blood oxygen levels at t=10 and 20 min, the rhinoceros remained severely hypoxemic for the remainder of the procedure (median PaO2=50.5 mm Hg, 95% confidence interval, 43.8-58.1). Median values for respiratory rate (5 breaths/min) and arterial partial pressure of carbon dioxide (PaCO2; 68.5 mm Hg) did not change significantly for the remaining 80 min. Median lactate, base excess, bicarbonate, and pH values improved between 20 and 100 min despite the persistent hypercapnia, indicating that the animals adequately compensated for respiratory and lactic acidosis. White rhinoceros were immobilized for 100 min with no negative effects

  2. ANABEL: intelligent blood-gas analysis in the intensive care unit.

    PubMed

    Zarkadakis, G; Carson, E R; Cramp, D G; Finkelstein, L

    1989-07-01

    ANABEL (ANalysis of Acid-Base status by Evaluating Lisp) is a prototype medical intelligent decision-support system aiming to assist clinicians in an Intensive Care Unit environment with the interpretation of blood-gas measurements. Its architecture is based on the merging of representations for declarative (domain-descriptive) and procedural (problem-solving) medical knowledge. The system performs diagnosis in two stages (tentative and differential) by first evaluating elementary computational units of procedural knowledge (procedures) and then abstracting their symbolic outputs in generating text. Thus, a 'semantic trace' is built which reflects the system's line of reasoning in reaching its conclusion. This paper describes the design aspects, development and clinical validation of ANABEL. PMID:2687421

  3. Method for extending the useful shelf-life of refrigerated red blood cells by flushing with inert gas

    DOEpatents

    Bitensky, Mark W.; Yoshida, Tatsuro

    1997-01-01

    Method using oxygen removal for extending the useful shelf-life of refrigerated red blood cells. A cost-effective, 4.degree. C. storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. Preservation of adenosine triphosphate levels and reduction in hemolysis and in membrane vesicle production of red blood cells stored at 4.degree. C. for prolonged periods of time is achieved by removing oxygen therefrom at the time of storage; in particular, by flushing with an inert gas. Adenosine triphosphate levels of the stored red blood cells are boosted in some samples by addition of ammonium phosphate.

  4. Gas and liquid chromatographic analyses of nimodipine calcium antagonist in blood plasma and cerebrospinal fluid.

    PubMed

    Krol, G J; Noe, A J; Yeh, S C; Raemsch, K D

    1984-01-13

    Gas (GC) and liquid chromatographic (LC) assay procedures were developed for analysis of nimodipine (1,4-dihydropyridine calcium antagonist, BAY e 9736) in blood plasma at low nanogram concentration levels. To avoid decomposition during gas chromatography, nimodipine was oxidized to nimodipine pyridine (P) analogue before it was chromatographed on the OV-17 column and quantitated using an electron-capture detector. In contrast, the LC procedure involved chromatographic separation and quantitation of the underivatized nimodipine and of the endogenous P analogue using a 3-micron Spherisorb ODS column and UV detection. The same plasma extract and three alternative internal standards were used for both assays. Taking into consideration the fact that the GC assay result includes endogenous P analogue as well as nimodipine, good correlation between GC and LC assay data was obtained. Comparison of the results observed with the two procedures confirmed the accuracy of each procedure and provided an alternative when one of the assay results was subject to patient plasma constituent interference. The LC assay was also used for analysis of the demethylated metabolites of nimodipine. To detect sub-nanogram concentrations of nimodipine in cerebrospinal fluid a combined LC-GC procedure using an LC clean-up step and a GC quantitation step was also developed. The above GC and LC procedures were used to obtain preliminary pharmacokinetic data. PMID:6707134

  5. Bilirubin measured on a blood gas analyser: a suitable alternative for near-patient assessment of neonatal jaundice?

    PubMed

    Peake, M; Mazzachi, B; Fudge, A; Bais, R

    2001-09-01

    The reliability of a recently released total bilirubin assay for a blood gas analyser was assessed in two Australian hospital laboratories. The instrument computes total bilirubin concentration from multi-wavelength absorbance measurements of undiluted whole blood or plasma. Performance of the Radiometer ABL 735 blood gas analyser bilirubin method (software version 3.6) was compared with a proven Roche diazo method for Hitachi analysers, calibrated using primary standards prepared from NIST SRM 916a bilirubin. Acceptable bilirubin results were found over a wide concentration range for most neonatal samples of whole blood or plasma. For adult specimens, bilirubin results were approximately 10% lower on the blood gas analyser. Within-run imprecision (whole blood) was < 2.5%, between-day imprecision (synthetic controls) < 1.0%, and the bilirubin assay for both whole blood and plasma was linear to 1,000 micromol/L. Using sampling options from 35 microL to 195 microL, bilirubin results differed by less than 3%, with a 95 microL syringe option producing the highest results. We conclude that the Radiometer ABL 735 bilirubin assay is suitable for near-patient assessment of neonatal jaundice using whole blood, thus eliminating the need for sample centrifugation. Verification using laboratory methods can be used when required. A positive correction of approximately 10% is required for adult specimens to conform with Hitachi results (SRM 916a calibration), possibly due to the optical characteristics of the higher proportion of conjugated bilirubin and other substances present in most adult samples. PMID:11587132

  6. An investigation of accelerating mode and decelerating mode constant-momentum mass spectrometry and their application to a residual gas analyzer

    NASA Technical Reports Server (NTRS)

    Ng, Y. S.

    1977-01-01

    A theoretical analysis of constant momentum mass spectrometry was made. A maximum resolving power for the decelerating mode constant momentum mass spectrometer was shown theoretically to exist for a beam of ions of known energy. A vacuum system and an electron beam ionization source was constructed. Supporting electronics for a residual gas analyzer were built. Experimental investigations of various types of accelerating and decelerating impulsive modes of a constant momentum mass spectrometer as applied to a residual gas analyzer were made. The data indicate that the resolving power for the decelerating mode is comparable to that of the accelerating mode.

  7. Sustained submaximal exercise does not alter the integrity of the lung blood-gas barrier in elite athletes.

    PubMed

    Hopkins, S R; Schoene, R B; Henderson, W R; Spragg, R G; West, J B

    1998-04-01

    The extreme thinness of the pulmonary blood-gas barrier results in high mechanical stresses in the capillary wall when the capillary pressure rises during exercise. We have previously shown that, in elite cyclists, 6-8 min of maximal exercise increase blood-gas barrier permeability and result in higher concentrations of red blood cells, total protein, and leukotriene B4 in bronchoalveolar lavage (BAL) fluid compared with results in sedentary controls. To test the hypothesis that stress failure of the barrier only occurs at the highest level of exercise, we performed BAL in six healthy athletes after 1 h of exercise at 77% of maximal O2 consumption. Controls were eight normal nonathletes who did not exercise before BAL. In contrast with our previous study, we did not find higher concentrations of red blood cells, total protein, and leukotriene B4 in the exercising athletes compared with control subjects. However, higher concentrations of surfactant apoprotein A and a higher surfactant apoprotein A-to-phospholipid ratio were observed in the athletes performing prolonged exercise, compared with both the controls and the athletes from our previous study. These results suggest that, in elite athletes, the integrity of the blood-gas barrier is altered only at extreme levels of exercise. PMID:9516183

  8. Contamination Analyzer

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Measurement of the total organic carbon content in water is important in assessing contamination levels in high purity water for power generation, pharmaceutical production and electronics manufacture. Even trace levels of organic compounds can cause defects in manufactured products. The Sievers Model 800 Total Organic Carbon (TOC) Analyzer, based on technology developed for the Space Station, uses a strong chemical oxidizing agent and ultraviolet light to convert organic compounds in water to carbon dioxide. After ionizing the carbon dioxide, the amount of ions is determined by measuring the conductivity of the deionized water. The new technique is highly sensitive, does not require compressed gas, and maintenance is minimal.

  9. Oxygen analyzer

    DOEpatents

    Benner, W.H.

    1984-05-08

    An oxygen analyzer which identifies and classifies microgram quantities of oxygen in ambient particulate matter and for quantitating organic oxygen in solvent extracts of ambient particulate matter. A sample is pyrolyzed in oxygen-free nitrogen gas (N/sub 2/), and the resulting oxygen quantitatively converted to carbon monoxide (CO) by contact with hot granular carbon (C). Two analysis modes are made possible: (1) rapid determination of total pyrolyzable obtained by decomposing the sample at 1135/sup 0/C, or (2) temperature-programmed oxygen thermal analysis obtained by heating the sample from room temperature to 1135/sup 0/C as a function of time. The analyzer basically comprises a pyrolysis tube containing a bed of granular carbon under N/sub 2/, ovens used to heat the carbon and/or decompose the sample, and a non-dispersive infrared CO detector coupled to a mini-computer to quantitate oxygen in the decomposition products and control oven heating.

  10. Oxygen analyzer

    DOEpatents

    Benner, William H.

    1986-01-01

    An oxygen analyzer which identifies and classifies microgram quantities of oxygen in ambient particulate matter and for quantitating organic oxygen in solvent extracts of ambient particulate matter. A sample is pyrolyzed in oxygen-free nitrogen gas (N.sub.2), and the resulting oxygen quantitatively converted to carbon monoxide (CO) by contact with hot granular carbon (C). Two analysis modes are made possible: (1) rapid determination of total pyrolyzable oxygen obtained by decomposing the sample at 1135.degree. C., or (2) temperature-programmed oxygen thermal analysis obtained by heating the sample from room temperature to 1135.degree. C. as a function of time. The analyzer basically comprises a pyrolysis tube containing a bed of granular carbon under N.sub.2, ovens used to heat the carbon and/or decompose the sample, and a non-dispersive infrared CO detector coupled to a mini-computer to quantitate oxygen in the decomposition products and control oven heating.

  11. Calculation and verification of blood ethanol measurement uncertainty for headspace gas chromatography.

    PubMed

    Sklerov, Jason H; Couper, Fiona J

    2011-09-01

    An estimate was made of the measurement uncertainty for blood ethanol testing by headspace gas chromatography. While uncertainty often focuses on compliance to a single threshold level (0.08 g/100 mL), the existence of multiple thresholds, related to enhanced sentencing, subject age, or commercial vehicle licensure, necessitate the use of an estimate with validity across multiple specification levels. The uncertainty sources, in order of decreasing magnitude, were method reproducibility, linear calibration, recovery, calibrator preparation, reference material, and sample preparation. A large set of reproducibility data was evaluated (n = 15,433) in order to encompass measurement variability across multiple conditions, operators, instruments, concentrations and timeframes. The relative, combined standard uncertainty was calculated as ±2.7%, with an expanded uncertainty of ±8.2% (99.7% level of confidence, k = 3). Bias was separately evaluated through a recovery study using standard reference material from a national metrology institute. The uncertainty estimate was verified through the use of proficiency test (PT) results. Assigned values for PT results and their associated uncertainties were calculated as robust means (x*) and standard deviations (s*) of participant values. Performance scores demonstrated that the uncertainty estimate was appropriate across the full range of PT concentrations (0.010-0.370 g/100 mL). The use of PT data as an empirical estimate of uncertainty was not examined. Until providers of blood ethanol PT samples include details on how an assigned value is obtained along with its uncertainty and traceability, the use of PT data should be restricted to the role of verification of uncertainty estimates. PMID:21871148

  12. Calculating CO2 and H2O eddy covariance fluxes from an enclosed gas analyzer using an instantaneous mixing ratio 2159

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eddy covariance flux research has relied on open- or closed-path gas analyzers for producing estimates of net ecosystem exchange of carbon dioxide (CO2) and water vapor (H2O). The two instruments have had different challenges that have led to development of an enclosed design that is intended to max...

  13. Radon-gas extraction and counting system for analyzing radon and radium in groundwater in seismically active areas

    SciTech Connect

    Knauss, K.

    1980-12-08

    A high concentration of radon in groundwater has attracted recent attention as a precursor of seismic activity. We have constructed a system that extracts and counts radon gas from solid, liquid, and gas samples. The radon is extracted in a closed system onto activated charcoal. The desorbed radon is then measured in a phosphored acrylic cell by scintillation counting of gross alpha radiation. The efficiency of the total system (extraction plus counting) is 90 +- 3% or better. Compact design and sturdy construction make the system completely portable and well suited to field operations in remote loations. Results are given for radon and radium in groundwaters in the Livermore area.

  14. Optical Transcutaneous pCO2 Sensor using Soft Lithography Method for Arterial Blood Gas Analysis

    NASA Astrophysics Data System (ADS)

    Kang, Byoung-Ho; Kim, Do-Eok; Leem, Myoung-Kun; Kwon, Dae-Hyuk; Lee, Kwang-Man; Kang, Shin-Won

    2008-10-01

    In this study, we carried out development of non-invasive optical transcutaneous partial pressure of carbon dioxide, pCO2, monitoring system. The purpose of this system is to detect CO2 from outer skin, not from the arterial blood-gathering method. There are advantages about a reduction of analysis time and real-time monitoring that this system might be available. The measurement system is composed of the IR lamp, the pyroelectric sensor including a 4.26 μm optical filter, the optical gas reaction chamber and the signal processing circuit. The optical reaction length of chamber was reduced by 1 mm using the soft-lithography method which CO2 is exhausted in human body as we considered. The fabricated pCO2 monitoring system showed linear result of 6.50×10-6 absorbance/ppm sensitivity for CO2 concentration from 0 ˜5,000 ppm by MFC and about 2 seconds of fast response time. The proposed system can be used in the optical biosensor field for the medical diagnosis such as pCO2 monitoring system and environment monitoring systems.

  15. Age- and Gender-Specific Reference Intervals for Fasting Blood Glucose and Lipid Levels in School Children Measured With Abbott Architect c8000 Chemistry Analyzer.

    PubMed

    Tamimi, Waleed; Albanyan, Esam; Altwaijri, Yasmin; Tamim, Hani; Alhussein, Fahad

    2012-04-01

    Reference intervals for pubertal characteristics are influenced by genetic, geographic, dietary and socioeconomic factors. Therefore, the aim of this study was to establish age-specific reference intervals of glucose and lipid levels among local school children. This was cross-sectional study, conducted among Saudi school children. Fasting blood samples were collected from 2149 children, 1138 (53%) boys and 1011 (47%) girls, aged 6 to 18 years old. Samples were analyzed on the Architect c8000 Chemistry System (Abbott Diagnostics, USA) for glucose, cholesterol, triglycerides, HDL and LDL. Reference intervals were established by nonparametric methods between the 2.5th and 97.5th percentiles. Significant differences were observed between boys and girls for cholesterol and triglycerides levels in all age groups (P < 0.02). Only at age 6-7 years and at adolescents, HDL and LDL levels were found to be significant (P < 0.001). No significant differences were seen in glucose levels except at age 12 to 13 years. Saudi children have comparable serum cholesterol levels than their Western counterparts. This may reflect changing dietary habits and increasing affluence in Saudi Arabia. Increased lipid screening is anticipated, and these reference intervals will aid in the early assessment of cardiovascular and diabetes risk in Saudi pediatric populations. PMID:23542765

  16. Analyzing Inquiry Questions of High-School Students in a Gas Chromatography Open-Ended Laboratory Experiment

    ERIC Educational Resources Information Center

    Blonder, Ron; Mamlock-Naaman, Rachel; Hofstein, Avi

    2008-01-01

    This paper describes the implementation of an open-ended inquiry experiment for high-school students, based on gas chromatography (GC). The research focuses on identifying the level of questions that students ask during the GC open inquiry laboratory, and it examines whether implementing the advanced inquiry laboratory opens up new directions for…

  17. Application of a Modified Gas Chromatograph to Analyze Space Experiment Combustion Gases on Space Shuttle Mission STS-94

    NASA Technical Reports Server (NTRS)

    Coho, William K.; Weiland, Karen J.; VanZandt, David M.

    1998-01-01

    A space experiment designed to study the behavior of combustion without the gravitational effects of buoyancy was launched aboard the Space Shuttle Columbia on July 1, 1997. The space experiment, designated as Combustion Module-1 (CM-1), was one of several manifested on the Microgravity Sciences Laboratory - 1 (MSL-1) mission. The launch, designated STS-94, had the Spacelab Module as the payload, in which the MSL-1 experiments were conducted by the Shuttle crewmembers. CM-1 was designed to accommodate two different combustion experiments during MSL-1. One experiment, the Structure of Flame Balls at Low Lewis-number experiment (SOFBALL), required gas chromatography analysis to verify the composition of the known, premixed gases prior to combustion, and to determine the remaining reactant and the products resulting from the combustion process in microgravity. A commercial, off-the-shelf, dual-channel micro gas chromatograph was procured and modified to interface with the CM-1 Fluids Supply Package and the CM-1 Combustion Chamber, to accommodate two different carrier gases, each flowing through its own independent column module, to withstand the launch environment of the Space Shuttle, to accept Spacelab electrical power, and to meet the Spacelab flight requirements for electromagnetic interference (EMI) and offgassing. The GC data was down linked to the Marshall Space Flight Center for near-real time analysis, and stored on-orbit for post-flight analysis. The gas chromatograph operated successfully during the entire SOFBALL experiment and collected 309 runs. Because of the constraints imposed upon the gas chromatograph by the CM-1 hardware, system and operations, it was unable to measure the gases to the required accuracy. Future improvements to the system for a re-flight of the SOFBALL experiment are expected to enable the gas chromatograph to meet all the requirements.

  18. Nitrogen removal characteristics analyzed with gas and microbial community in thermophilic aerobic digestion for piggery waste treatment.

    PubMed

    Lee, J W; Lee, H W; Kim, S W; Lee, S Y; Park, Y K; Han, J H; Choi, S I; Yi, Y S; Yun, Z

    2004-01-01

    In order to characterize the nitrogen conversion characteristics in a thermophilic aerobic digestion (TAD) system, a laboratory study has been conducted with the analysis of effluent gas and microbial community in the sludge samples. The lab TAD system was operated with HRT of 3 days and 60 degrees C. Based on the nitrogen mass balance, it has been found that about 2/3 of the daily load of nitrogen was converted to the gaseous form of nitrogen whereas cellular transformation and unmetabolized nitrogen accounted for about 1/3. Among the gaseous nitrogen transformation, significant amount of influent nitrogen had been converted to N2 gas (29% of influent N) and N2O (9% of influent N). Ammonia conversion was only 28% of influent N. The detection of N2O gas is a clear indication of the biological nitrogen reduction process in the thermophilic aerobic digester. No conclusive evidence for the existence of aerobic deammonification has been found. The microbial community analysis showed that thermophilic bacteria such as Bacillus thermocloacae, Bacillus sp. and Clostridial groups dominated in this TAD reactor. The diverse microbial community in TAD sludge may play an important role in removing both strong organics and nitrogen from piggery waste. PMID:15137444

  19. Screening and determination of benzodiazepines in whole blood using solid-phase extraction and gas chromatography/mass spectrometry.

    PubMed

    Inoue, H; Maeno, Y; Iwasa, M; Matoba, R; Nagao, M

    2000-09-11

    Benzodiazepines are one of the most widely prescribed drugs for the treatment of a wide spectrum of clinical disorders. They are used as anticonvulsants, anxiolytics, hypnotics or muscle relaxants with different duration of action. In this paper, a simple and sensitive method for the determination of benzodiazepines in whole blood using solid-phase extraction and gas chromatography/mass spectrometry (GC/MS) is described. The drugs spiked in whole blood were extracted with an Oasis HLB solid-phase extraction cartridge (Waters), which contains a copolymer designed to have a hydrophilic-lipophilic balance. GC/MS analysis was performed using a Shimadzu QP-5000 equipped with a BPX5 capillary column (15 mx0.32 mm I.D., film thickness 0.25 microm, SGE). Nineteen benzodiazepines and two thienodiazepines were well separated from each other on their SIM chromatograms and also on the TIC with the exception of oxazolam to cloxazolam separation. The blank extract from whole blood gave no peaks that interfered with all benzodiazepines and thienodiazepines on the chromatogram. The calibration curves for selected benzodiazepines with fludiazepam as an internal standard showed excellent linearity over the concentration range 5-500 ng/ml blood with a correlation coefficients of >0.995. The detection limits ranged from 0.2 to 20 ng/ml blood. The method is simple and sensitive for the determination of benzodiazepines in whole blood and seems to be useful in the practice of forensic science. PMID:10978650

  20. Measurements of NOx, acyl peroxynitrates, and NOy with automatic interference corrections using a NO2 analyzer and gas phase titration.

    PubMed

    Hargrove, James; Zhang, Jingsong

    2008-04-01

    NO(2) analyzers are much more valuable if they can also measure NO since the two (NO+NO(2)=NO(x)) are often found together. NO can be quantitatively converted to NO(2) by reaction with ozone and subsequent thermal decomposition of the N(2)O(5) that may form from further oxidation. The conversion of NO, along with decomposition of N(2)O(5) and removal of the remaining unreacted ozone with a heated chamber, allows for quantitative determination of NO(x) using a NO(2) analyzer and the determination of decomposed acyl peroxynitrates. Ambient tests are performed to demonstrate these methods. PMID:18447567

  1. Gas exchange as monitored in mixed venous and arterial blood during experimental cardiopulmonary resuscitation.

    PubMed

    Wiklund, L; Jorfeldt, L; Stjernström, H; Rubertsson, S

    1992-07-01

    Nineteen anaesthetized piglets were investigated. After catheterization and a stabilization period, ventricular fibrillation was induced with a transthoracic DC shock, after which a 10-min period of cardiopulmonary resuscitation (CPR) took place. CPR included manual chest compression and mechanical ventilation with pure oxygen. After 1 min of CPR, an infusion of alkaline buffer was begun and completed within 5 min. A total of 50 mmol of either sodium bicarbonate (n = 6) or tris buffer mixture (n = 7) were given. These two groups were compared with a third control group (n = 6) receiving the same volume of normal saline. After 8 min of CPR all animals were given 0.5 mg adrenaline i.v., and after 10 min DC shocks were used to revert the heart back to normal sinus rhythm. Our results demonstrate that blood flow and not ventilation is the limiting factor for the efficient disposal of CO2 during CPR. This also applied when the demand for CO2 transport was increased by administration of sodium bicarbonate. The respiratory exchange ratio increased 1.9-fold, indicating that the transport of carbon dioxide was less affected than that of oxygen. The estimated alveolo-arterial oxygen tension difference, shunt, and overall ventilation/perfusion ratio increased, creating an inverse hyperbolic relationship between arterial PCO2 and PO2. The difference between mixed venous and arterial PCO2 correlated well to the mixed venous PCO2, implying more efficient pulmonary elimination of PCO2 when the mixed venous PCO2 was high. Pulmonary gas exchange during CPR appears to be independent of alkaline buffer therapy in the form of sodium bicarbonate or tris buffer mixture.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1632165

  2. Evaluation of a novel in-line point-of-care blood gas analyser.

    PubMed

    Miles, L F; Giraud, K; Ferris, R; Klein, A A; Martinez, G C; Jenkins, D P; Saulankey, K

    2016-09-01

    Point-of-care testing is becoming increasingly relevant to the practice of anaesthesia and critical care medicine, especially in terms of minimisation of sample volumes and decreased time to decision making. We performed a prospective observational study to evaluate a novel, in-line blood gas analysis device against a conventional benchtop model, and assessed it while placing the enrolled patients under extreme physiological conditions, specifically deep hypothermic circulatory arrest. Eight patients were studied, and had between seven and 11 samples analysed for seven variables (pH, pCO2 , pO2 , HCO3 (-) , base excess [BE], K(+) and haematocrit [Hct]), using the device during the process of cooling to 20 °C on cardiopulmonary bypass, and subsequent rewarming to normothermia. After Passing-Bablok analysis, the variables were evaluated for bias, limits of agreement and percentage error at above and below 30 °C. Of the measured variables, only pH (percentage error 2.4%) and potassium (19.8%) demonstrated acceptable (< 30%) percentage error over the full range of temperatures measured. Carbon dioxide, when stratified by temperature, was acceptable (< 30 °C percentage error 24.6%, > 30 °C percentage error 9.9%), but the overall percentage error of the dataset (45.8%) was excessively high. Bicarbonate and haematocrit both had an acceptable percentage error above 30 °C (25.2% and 18.5%, respectively), but similar to carbon dioxide, percentage error for the full range of temperatures exceeded 30%. These data differ from previous work examining this device, and highlights the difference between derived measures using different apparatuses when exposed to extreme physiological conditions. PMID:27523052

  3. EVENT84 user's manual: a computer code for analyzing explosion-induced gas-dynamic transients in flow networks

    SciTech Connect

    Martin, R.A.; Wilson, T.L.

    1984-12-01

    This manual supports the computer code EVENT84, which can predict explosion-induced gas-dynamic transients in flow networks. The code can model transients in any arbitrarily designated network of building rooms and ventilation systems. A lumped-parameter formulation is used. EVENT84 was designed to provide a safety analysis tool for he nuclear, chemical, and mining industries. It is particularly suitable for calculating the detailed effects of explosions in the far field using a parametric representation of the explosive event. The code input and a sample problem that illustrates its capabilities are provided.

  4. Blood gas and patient safety: considerations based on experience developed in accordance with the Risk Management perspective.

    PubMed

    Rambaldi, Marco; Baranzoni, Mariateresa; Coppolecchia, Pasquale; Moschello, Jennifer N; Novaco, Francesca

    2007-01-01

    It is the responsibility of health organizations to guarantee a high level of healthcare by using adequate methodologies and instruments, creating secure conditions for treatment, and preventing adverse events due to human or system errors. It is necessary to introduce Risk Management programs, and in particular to promote Clinical Risk Management, one of the constituent elements of Clinical Governance, to assure the delivery of high-quality performance and services. In the point-of-care testing (POCT) context, using an analysis of our experiences, we discuss the entire analytical process, including acquisition and usage, while focusing on blood gas analyzers. Our experience confirms that within a Clinical Governance framework, it is necessary to apply, even when choosing instruments, a systematic vision that is not limited to analytical validation, but also includes an in-depth analysis of the impact in a specific context. Assessment of the correlated risks, independent of the analytical methodology used, is indispensable in a clinical environment to identify the most suitable approach for such risks. A study of the latent factors can be proactively performed to identify (and stimulate) what the pre-organizational environment (producer companies) can offer in terms of product orientation to effectively reduce correlated risk during use. Among the different options for possible treatment of risk, one involves the transfer of the assumption of risk to third parties (e.g., maintenance and quality controls). Transferring the responsibility for control operations to the operator of the instrument, which follows the quality controls with total autonomy, is equivalent to transferring the correlated risk for the clinician (in the POCT case) to the producer, who becomes the guarantor. In practice this is equivalent to a specific assurance stipulation with zero cost. PMID:17579531

  5. Directional molecular flow analysis and leak detection with a rotatable gas analyzer in a large space simulation chamber

    NASA Technical Reports Server (NTRS)

    Ehlers, H. K. F.

    1972-01-01

    A system was developed and applied at the NASA Manned Spacecraft Center for measuring and analyzing directional molecular flows in a large thermal vacuum chamber in order to verify molecular environment and identify characteristic and abnormal test article and chamber conditions. The system is described, and some results obtained in over 1200 hours of operation are given.

  6. Alveolar gas exchange and tissue oxygenation during incremental treadmill exercise, and their associations with blood O2 carrying capacity

    PubMed Central

    Rissanen, Antti-Pekka E.; Tikkanen, Heikki O.; Koponen, Anne S.; Aho, Jyrki M.; Hägglund, Harriet; Lindholm, Harri; Peltonen, Juha E.

    2012-01-01

    The magnitude and timing of oxygenation responses in highly active leg muscle, less active arm muscle, and cerebral tissue, have not been studied with simultaneous alveolar gas exchange measurement during incremental treadmill exercise. Nor is it known, if blood O2 carrying capacity affects the tissue-specific oxygenation responses. Thus, we investigated alveolar gas exchange and tissue (m. vastus lateralis, m. biceps brachii, cerebral cortex) oxygenation during incremental treadmill exercise until volitional fatigue, and their associations with blood O2 carrying capacity in 22 healthy men. Alveolar gas exchange was measured, and near-infrared spectroscopy (NIRS) was used to monitor relative concentration changes in oxy- (Δ[O2Hb]), deoxy- (Δ[HHb]) and total hemoglobin (Δ[tHb]), and tissue saturation index (TSI). NIRS inflection points (NIP), reflecting changes in tissue-specific oxygenation, were determined and their coincidence with ventilatory thresholds [anaerobic threshold (AT), respiratory compensation point (RC); V-slope method] was examined. Blood O2 carrying capacity [total hemoglobin mass (tHb-mass)] was determined with the CO-rebreathing method. In all tissues, NIPs coincided with AT, whereas RC was followed by NIPs. High tHb-mass associated with leg muscle deoxygenation at peak exercise (e.g., Δ[HHb] from baseline walking to peak exercise vs. tHb-mass: r = 0.64, p < 0.01), but not with arm muscle- or cerebral deoxygenation. In conclusion, regional tissue oxygenation was characterized by inflection points, and tissue oxygenation in relation to alveolar gas exchange during incremental treadmill exercise resembled previous findings made during incremental cycling. It was also found out, that O2 delivery to less active m. biceps brachii may be limited by an accelerated increase in ventilation at high running intensities. In addition, high capacity for blood O2 carrying was associated with a high level of m. vastus lateralis deoxygenation at peak exercise

  7. Recent improvements in mobile greenhouse gas analyzers and what they have done for top-down emissions verification

    NASA Astrophysics Data System (ADS)

    Sweeney, C.

    2015-12-01

    Recent advances in in-situ measurements of CO2, CH4 and N2O along with their isotopes and other associated tracers on moving platforms have opened the door to significant opportunities for directly measuring emissions of greenhouse gases from distributed and single-point emitters. By coupling advances in the stability and portability of these measurements with new techniques for sampling trace gases, it has been possible to advance our understanding of the processes that contribute most to greenhouse gas emissions, to understand the distribution of these emissions in space and magnitude, as well as to quantify the regional impact of these emissions. These advances can best be illustrated through the recent focus on the CH4 emissions from oil and gas production in the US and the deployment of in-situ measurements on aircraft, automobiles and unmanned aerial vehicles (UAVs). Although these recent advances have significantly improved our ability to verify emission inventory estimates of CH4 emissions there are still gaps in our ability to extract multi-species information from point-source emissions and our ability to fully utilize the smaller UAV platforms that have reduced payload capacity and power.

  8. A quantitative headspace-solid-phase microextraction-gas chromatography-flame ionization detector method to analyze short chain free fatty acids in rat feces.

    PubMed

    Fiorini, Dennis; Boarelli, Maria Chiara; Gabbianelli, Rosita; Ballini, Roberto; Pacetti, Deborah

    2016-09-01

    This study sought to develop and validate a quantitative method to analyze short chain free fatty acids (SCFAs) in rat feces by solid-phase microextraction and gas chromatography (SPME-GC) using the salt mixture ammonium sulfate and sodium dihydrogen phosphate as salting out agent. Conditioning and extraction time, linearity, limits of detection and quantification, repeatability, and recovery were evaluated. The proposed method allows quantification with improved sensitivity as compared with other methods exploiting SPME-GC. The method has been applied to analyze rat fecal samples, quantifying acetic, propionic, isobutyric, butyric, isopentanoic, pentanoic, and hexanoic acids. PMID:27267560

  9. Investigation on the Importance of Fast Air Temperature Measurements in the Sampling Cell of Short-Tube Closed-Path Gas Analyzer for Eddy-Covariance Fluxes

    NASA Astrophysics Data System (ADS)

    Kathilankal, J. C.; Fratini, G.; Burba, G. G.

    2014-12-01

    High-speed, precise gas analyzers used in eddy covariance flux research measure gas content in a known volume, thus essentially measuring gas density. The classical eddy flux equation, however, is based on the dry mole fraction. The relation between dry mole fraction and density is regulated by the ideal gas law and law of partial pressures, and depends on water vapor content, temperature and pressure of air. If the instrument can output precise fast dry mole fraction, the flux processing is significantly simplified and WPL terms accounting for air density fluctuations are no longer required. This will also lead to the reduction in uncertainties associated with the WPL terms. For instruments adopting an open-path design, this method is difficult to use because of complexities with maintaining reliable fast temperature measurements integrated over the entire measuring path, and also because of extraordinary challenges with accurate measurements of fast pressure in the open air flow. For instruments utilizing a traditional long-tube closed-path design, with tube length 1000 or more times the tube diameter, this method can be used when instantaneous fluctuations in the air temperature of the sampled air are effectively dampened, instantaneous pressure fluctuations are regulated or negligible, and water vapor is measured simultaneously with gas, or the sample is dried. For instruments with a short-tube enclosed design, most - but not all - of the temperature fluctuations are attenuated, so calculating unbiased fluxes using fast dry mole fraction output requires high-speed, precise temperature measurements of the air stream inside the cell. In this presentation, authors look at short-term and long-term data sets to assess the importance of high-speed, precise air temperature measurements in the sampling cell of short-tube enclosed gas analyzers. The CO2 and H2O half hourly flux calculations, as well as long-term carbon and water budgets, are examined.

  10. Absence of salting out effects in forensic blood alcohol determination at various concentrations of sodium fluoride using semi-automated headspace gas chromatography.

    PubMed

    Miller, B A; Day, S M; Vasquez, T E; Evans, F M

    2004-01-01

    Blood alcohol measurements determined by headspace gas chromatography have been challenged on the grounds that the presence of the preservative sodium fluoride in blood samples artificially increases headspace alcohol concentrations due to a salting out effect. Blood samples containing varying amounts of ethanol and sodium fluoride were tested using semi-automated headspace gas chromatography with n-propyl alcohol as the internal standard to assess the validity of this challenge. We find, in fact, that under these test conditions the measured alcohol levels are systematically depressed as the amount of sodium fluoride in the blood sample increases. The challenge thus has no basis. PMID:15112594

  11. Gas diffusion liquid storage bag and method of use for storing blood

    NASA Technical Reports Server (NTRS)

    Bank, H.; Cleland, E. L. (Inventor)

    1979-01-01

    The shelf life of stored whole blood may be doubled by adding a buffer which maintains a desired pH level. However, this buffer causes the generation of CO2 which, if not removed at a controlled rate, causes the pH value of the blood to decrease, which shortens the useful life of the blood. A blood storage bag is described which permits the CO2 to be diffused out at a controlled rate into the atmosphere, thereby maintaining the desired pH value and providing a bag strong enough to permit handling.

  12. Group theoretic method for analyzing interaction of a discontinuity wave with a strong shock in an ideal gas

    NASA Astrophysics Data System (ADS)

    Pandey, Manoj

    2010-02-01

    A group theoretic method is used to obtain an exact particular solution to the system of partial differential equations, describing one-dimensional unsteady planar, cylindrically and spherically symmetric motions in an ideal gas, involving shock waves. It is interesting to remark that the exact solution obtained here is precisely the blast wave solution obtained earlier using a different method of approach. Further, the evolution of a discontinuity wave and its interaction with the strong shock are studied within the state characterized by the exact particular solution. The properties of reflected and transmitted waves and the jump in the shock acceleration are completely characterized, and certain observations are noted in respect to their contrasting behavior.

  13. Examination of platelet function in whole blood under dynamic flow conditions with the cone and plate(let) analyzer: effect of erythrocytosis and thrombocytosis.

    PubMed

    Peerschke, Ellinor I; Silver, Richard T; Weksler, Babette B; Yin, Wei; Bernhardt, Bernard; Varon, David

    2007-03-01

    We studied cone and plate(let) analysis (CPA) for evaluating global platelet function in whole blood under arterial flow conditions (approximately 1,800 seconds(-1)). CPA allows direct visualization and quantitation of platelet adhesion (surface coverage [SC]) and determination of average aggregate size (AS) following brief shearing of a small blood sample (3.2% sodium citrate) in plastic wells. By using blood from healthy volunteers manipulated to alter platelet or RBC counts and blood from patients with myeloproliferative disorders (MPDs), quantitative and qualitative changes in SC and AS were observed. Thrombocytosis resulted in increased SC, whereas erythrocytosis increased AS. The RBC volume (mean corpuscular volume) had no effect. It is interesting that differences in CPA AS were discerned among subgroups of patients with MPD undergoing different treatment regimens. These studies suggest that CPA platelet deposition patterns may provide novel insight into global platelet function during hemodynamic flow. PMID:17276938

  14. Blood gas analyses and other components involved in the acid–base metabolism of rats infected by Trypanosoma evansi

    PubMed Central

    Baldissera, Matheus D.; Vaucher, Rodrigo A.; Oliveira, Camila B.; Rech, Virginia C.; Sagrillo, Michele R.; Stainki, Daniel R.; França, Raqueli T.; Machado, Gustavo; Lopes, Sonia T.A.; Monteiro, Silvia G.; Stefani, Lenita M.; Da Silva, Aleksandro S.

    2014-01-01

    The aim of this study was to investigate the effects of Trypanosoma evansi infections on arterial blood gases of experimentally infected rats. Two groups with eight animals each were used; group A (uninfected) and group B (infected). Infected animals were daily monitored through blood smears that showed high parasitemia with 30 trypanosomes per field (1000×) on average, 5 days post-infection (PI). Arterial blood was collected at 5 days PI for blood gas analysis using an automated method based on dry-chemistry. Hydrogen potential (pH), partial oxygen pressure (pO2), oxygen saturation (sO2), sodium (Na), ionic calcium (Ca ionic), chlorides (Cl), partial dioxide carbon pressure (pCO2), base excess (BE), base excess in the extracellular fluid (BEecf), bicarbonate (cHCO3), potassium (K), lactate, and blood total dioxide the carbon (tCO2) were evaluated. The levels of pH, pCO2, BE, BEecf, cHCO3, and tCO2 were significantly decreased (P < 0.05) in group B compared to group A. Additionally, the same group showed increases in Cl and lactate levels when compared to uninfected group. Therefore, it is possible to state that the infection caused by T. evansi led to alterations in the acid–base status, findings that are correlated to metabolic acidosis. PMID:26644945

  15. Regional Mapping of Gas Uptake by Blood and Tissue in the Human Lung using Hyperpolarized Xenon-129 MRI

    PubMed Central

    Qing, Kun; Ruppert, Kai; Jiang, Yun; Mata, Jaime F.; Miller, G. Wilson; Shim, Y. Michael; Wang, Chengbo; Ruset, Iulian C.; Hersman, F. William; Altes, Talissa A.; Mugler, John P.

    2013-01-01

    Purpose To develop a breath-hold acquisition for regional mapping of ventilation and the fractions of hyperpolarized xenon-129 (Xe129) dissolved in tissue (lung parenchyma and plasma) and red blood cells (RBCs), and to perform an exploratory study to characterize data obtained in human subjects. Materials and Methods A three-dimensional, multi-echo, radial-trajectory pulse sequence was developed to obtain ventilation (gaseous Xe129), tissue and RBC images in healthy subjects, smokers and asthmatics. Signal ratios (total dissolved Xe129 to gas, tissue-to-gas, RBC-to-gas and RBC-to-tissue) were calculated from the images for quantitative comparison. Results Healthy subjects demonstrated generally uniform values within coronal slices, and a gradient in values along the anterior-to-posterior direction. In contrast, images and associated ratio maps in smokers and asthmatics were generally heterogeneous and exhibited values mostly lower than those in healthy subjects. Whole-lung values of total dissolved Xe129 to gas, tissue-to-gas, and RBC-to-gas ratios in healthy subjects were significantly larger than those in diseased subjects. Conclusion Regional maps of tissue and RBC fractions of dissolved Xe129 were obtained from a short breath-hold acquisition, well tolerated by healthy volunteers and subjects with obstructive lung disease. Marked differences were observed in spatial distributions and overall amounts of Xe129 dissolved in tissue and RBCs among healthy subjects, smokers and asthmatics. PMID:23681559

  16. Simulation model for analyzing voltage-current characteristics of the barrier type lamp filled with Hg-Ar gas

    NASA Astrophysics Data System (ADS)

    Watanabe, Yoshio; Yamaguchi, Tomohiro; Imada, Ryosuke

    2013-09-01

    The simulation model for DBD lamp filled with Hg-Ar gas is studied. The straight tube filled with Hg and Ar gases is employed as a lamp. Three kinds of applied voltage waveforms at high frequency are applied between the pair of stripe electrodes attached on the outside of the tube. One dimensional model is employed. Ionization frequency based on Townsend ionization coefficient is employed in this model. A try-and-error method is employed to estimate the value of each coefficient, and the calculated waveform is compared with the measured current waveform. The values by which the most similar current waveform to the measurement is obtained are selected as appropriate values. Using these coefficient values, the discharge current waveforms by the applying voltage with triangular waveform and trapezoidal waveforms are calculated and compared with the measured current waveforms. Good agreements between the calculation and the measurement in discharge current waveform are obtained for three types of applied voltage waveform. Then, the distributions of electric field, electron density and ion density in the discharge space are calculated. It is shown that the space charge layer is formed on the glass tube wall and ionization takes place mainly in the space charge layer. Professor

  17. Effects of body position, hyperinflation, and blood gas tensions on maximal respiratory pressures in patients with chronic obstructive pulmonary disease.

    PubMed Central

    Heijdra, Y. F.; Dekhuijzen, P. N.; van Herwaarden, C. L.; Folgering, H. T.

    1994-01-01

    BACKGROUND--Inspiratory muscle strength in patients with chronic obstructive pulmonary disease (COPD) can be affected by mechanical factors which influence the length of the diaphragm, and by non-mechanical factors. The aim of the present study was to evaluate firstly the effects of body position on respiratory pressures and, secondly, to determine the relative contribution of age, body mass index (BMI), lung volumes, and arterial blood gas tensions to respiratory muscle strength. METHODS--Thirty male patients with stable COPD (mean FEV1 40.4% predicted) participated in the study. Maximal inspiratory and expiratory mouth pressures (PImax, PEmax) and maximal inspiratory transdiaphragmatic pressures (PDI) in the sitting and supine position, lung function, and arterial blood gas tensions were measured. RESULTS--Mean (SD) PImax in the sitting position was higher than in the supine position (7.1(2.3)kPa v 6.4(2.2)kPa respectively). In contrast, PDI in the sitting position was lower than in the supine position (10.0(3.5)kPa v 10.8(3.7)kPa respectively). PEmax was higher in the sitting position (9.3(3.0)kPa) than in the supine position (8.7(2.8)kPa). Significant correlations were found between inspiratory muscle strength on the one hand, and lung function parameters, BMI, and arterial blood gas tensions on the other. CONCLUSIONS--Inspiratory muscle strength in patients with COPD is influenced by mechanical factors (body position, lung volumes) and non-mechanical factors (BMI, FEV1, and blood gases). PImax and PEmax are lower in the supine position while, in contrast to healthy subjects, PDI is higher in the supine position than in the sitting position. PMID:8016765

  18. Analyzing Trace Gas Measurements to Understand Convective Dynamics: Results from SEAC4RS Field Campaign and Mozaic Project

    NASA Astrophysics Data System (ADS)

    Luo, Z. J.; Pyo, S.; Shah, N.

    2014-12-01

    Deep convective updrafts transport air parcels from near the PBL to the upper troposphere in about 20-30 min. At this time scale, most insoluble trace gases (e.g., ozone, some VOCs) can be treated as nearly conserved tracers. While the atmospheric chemistry community is most interested in the chemical consequences of the trace gases being lofted, these composition measurements, if sampled properly inside and near convection, can be utilized to study convective dynamics including lateral entrainment and mixing in the outflow. We will use measurements made from a recent NASA field campaign, SEAC4RS to illustrate how such studies can be conducted. Also, we analyzed long-term data from MOZAIC project to corroborate the findings from SEAC4RS. It will be shown that using trace gases to diagnose convective dynamics sometimes has certain advantages over the traditional meteorological approach using, e.g., equivalent potential temperature.

  19. Significance of High-Speed Air Temperature Measurements in the Sampling Cell of a Closed-Path Gas Analyzer with a Short Tube

    NASA Astrophysics Data System (ADS)

    Kathilankal, James; Fratini, Gerardo; Burba, George

    2015-04-01

    Eddy covariance gas analyzers measure gas content in a known volume, thus essentially measuring gas density. The fundamental flux equation, however, is based on the dry mole fraction. The relationship between dry mole fraction and density is regulated by the ideal gas law describing the processes of temperature- and pressure-related expansions and contractions, and by the law of partial pressures, describing the process of dilution. As a result, this relationship depends on water vapor content, temperature and pressure of the air sample. If the instrument is able to output precise high-speed dry mole fraction, the flux processing is significantly simplified and WPL density terms accounting for the air density fluctuations are no longer required. This should also lead to the reduction in uncertainties associated with the density terms resulting from the eddy covariance measurements of sensible and latent heat fluxes used in these terms. In this framework, three main measurement approaches may be considered: Open-path approach Outputting correct high-speed dry mole fraction from the open-path instrument is difficult because of complexities with maintaining reliable fast temperature measurements integrated over the entire measuring path, and also because of extraordinary challenges with accurate measurements of fast pressure in the open air flow. Classical long-tube closed-path approach For instruments utilizing traditional long-tube closed-path design, with tube length 1000 or more times the tube diameter, the fast dry mole fraction can be used successfully when instantaneous fluctuations in the air temperature of the sampled air are effectively dampened to negligible levels, instantaneous pressure fluctuations are regulated or negligible, and water vapor is measured simultaneously with gas or the air sample is dried. Short-tube closed-path approach, the enclosed design For instruments with a short-tube enclosed design, most - but not all - of the temperature

  20. The effects of short- and long-term hypoxia on hemolymph gas values in the American horseshoe crab (Limulus polyphemus) using a point-of-care analyzer.

    PubMed

    Allender, Matthew C; Schumacher, Juergen; George, Robert; Milam, Jennifer; Odoi, Agricola

    2010-06-01

    Hemolymph gas parameters were evaluated using a point-of-care analyzer in healthy American horseshoe crabs (Limulus polyphemus) at rest and after short- and long-term removal from water. Baseline vascular pH, partial pressure of oxygen (PO2), partial pressure of carbon dioxide, bicarbonate, base excess, total carbon dioxide, and lactate concentrations were determined from hemolymph samples collected from 10 horseshoe crabs (group 1) submerged in water and were compared with values after removal from water for 5 min, and after recovery in water for 10 min and for longer than 60 min (range, 61-221 min). Hemolymph gas parameters were also determined in 12 horseshoe crabs (group 2) after shipment out of water for 24 hr and were compared with values obtained from group 1 animals. Baseline hemolymph gas values of the American horseshoe crab are within range for other aquatic vertebrates. After removal from water for 5 min, all group 1 crabs developed severe hypoxia, with PO2 levels falling below the detectable limit of the analyzer. Group 2 crabs had pronounced respiratory acidosis, and their PO2 values were significantly below baseline values of group 1 animals. PMID:20597209

  1. A radial differential mobility analyzer for the size-classification of gas-phase synthesized nanoparticles at low pressures

    NASA Astrophysics Data System (ADS)

    Nanda, K. K.; Kruis, F. E.

    2014-07-01

    Differential mobility analyzers (DMAs) are commonly used to generate monodisperse nanoparticle aerosols. Commercial DMAs operate at quasi-atmospheric pressures and are therefore not designed to be vacuum-tight. In certain particle synthesis methods, the use of a vacuum-compatible DMA is a requirement as a process step for producing high-purity metallic particles. A vacuum-tight radial DMA (RDMA) has been developed and tested at low pressures. Its performance has been evaluated by using a commercial NANO-DMA as the reference. The performance of this low-pressure RDMA (LP-RDMA) in terms of the width of its transfer function is found to be comparable with that of other NANO-DMAs at atmospheric pressure and is almost independent of the pressure down to 30 mbar. It is shown that LP-RDMA can be used for the classification of nanometer-sized particles (5-20 nm) under low pressure condition (30 mbar) and has been successfully applied to nanoparticles produced by ablating FeNi at low pressures.

  2. Comprehensive two-dimensional gas chromatography coupled with static headspace sampling to analyze volatile compounds: application to almonds.

    PubMed

    Manzano, Pilar; Diego, Juan Carlos; Bernal, José Luis; Nozal, María Jesús; Bernal, José

    2014-03-01

    The hyphenation of static headspace sampling with comprehensive 2D GC equipped with a modulator based on capillary flow technology and a flame ionization detector was used to separate and identify 43 representative target volatile compounds (light hydrocarbons, carbonyls, pyrazines, alcohols, furans, and benzenes) frequently detected in the roasting process of nuts. Five column combinations with differing degrees of orthogonality (one conventional and four inverted phase sets) were tested in order to obtain the best conditions for analyzing these volatile compounds. Optimization of the working conditions for each of the different column combinations was performed by means of a central composite design. The best results in terms of separation and differentiation among the different chemical groups were achieved with a combination of inverted phase columns (first dimension: highly polar, INNOWax; second dimension: mid-polar, ZB-35). Additionally, a reference template was developed to provide an effective and rapid analysis of the target compounds. Finally, the proposed method was successfully employed to identify volatile compounds in raw and roasted almond samples from the Spanish cultivar Largueta. PMID:24420911

  3. Application of the Reference Method Isotope Dilution Gas Chromatography Mass Spectrometry (ID/GC/MS) to Establish Metrological Traceability for Calibration and Control of Blood Glucose Test Systems

    PubMed Central

    Andreis, Elisabeth; Küllmer, Kai

    2014-01-01

    Self-monitoring of blood glucose (BG) by means of handheld BG systems is a cornerstone in diabetes therapy. The aim of this article is to describe a procedure with proven traceability for calibration and evaluation of BG systems to guarantee reliable BG measurements. Isotope dilution gas chromatography mass spectrometry (ID/GC/MS) is a method that fulfills all requirements to be used in a higher-order reference measurement procedure. However, this method is not applicable for routine measurements because of the time-consuming sample preparation. A hexokinase method with perchloric acid (PCA) sample pretreatment is used in a measurement procedure for such purposes. This method is directly linked to the ID/GC/MS method by calibration with a glucose solution that has an ID/GC/MS-determined target value. BG systems are calibrated with whole blood samples. The glucose levels in such samples are analyzed by this ID/GC/MS-linked hexokinase method to establish traceability to higher-order reference material. For method comparison, the glucose concentrations in 577 whole blood samples were measured using the PCA-hexokinase method and the ID/GC/MS method; this resulted in a mean deviation of 0.1%. The mean deviation between BG levels measured in >500 valid whole blood samples with BG systems and the ID/GC/MS was 1.1%. BG systems allow a reliable glucose measurement if a true reference measurement procedure, with a noninterrupted traceability chain using ID/GC/MS linked hexokinase method for calibration of BG systems, is implemented. Systems should be calibrated by means of a traceable and defined measurement procedure to avoid bias. PMID:24876614

  4. Fast-response CO2 mixing-ratio measurement with an open-path gas analyzer for eddy-flux applications

    NASA Astrophysics Data System (ADS)

    Bogoev, I.

    2014-12-01

    Infra-red gas analyzers operate on the principle of light absorption and measure the density of the gas in the sensing path. To account for density fluctuations caused by barometric pressure, thermal expansion and contraction, and water-vapor dilution, flux calculations using CO2 density measurements need to be corrected for sensible and latent heat transfer (also known as WPL corrections). In contrast, these corrections are not required if the flux calculation involves CO2 mixing ratio relative to dry air. Historically, CO2 mixing ratio measurements have been available only for analyzers with a closed-path where temperature fluctuations in the air sample are attenuated in the intake tubing to a level that they are adequately measured by a contact thermometer. Open-path gas analyzers are not able to make in situ CO2 mixing-ratio measurements because of the unavailability of a reliable, accurate and fast-response air-temperature sensor in the optical path. A newly developed eddy-flux system integrates an aerodynamic open-path gas analyzer with a sonic anemometer where the sensing volumes of the two instruments coincide. Thus the system has the ability to provide temporally and spatially synchronized fast-response measurements of the 3D wind vector, sonically derived air temperature, CO2 and water vapor densities. When these measurements are combined with a fast-response static pressure measurement an instantaneous in-situ CO2 mixing ratio can be calculated on-line, eliminating the need for density corrections in post-processing. In this study fluxes computed from CO2 mixing-ratio are compared to WPL corrected fluxes using CO2 density. Results from a field inter-comparison with an aspirated temperature probe suggest that accurate, fast response air temperature can be derived from humidity-corrected speed of sound measurements. Biases due to heat exchange with the analyzer surface are evaluated by comparing atmospheric sensible heat flux measurements with a

  5. Eddy Covariance Measurements of Methane Flux at Remote Sites with New Low-Power Lightweight Fast Gas Analyzer

    NASA Astrophysics Data System (ADS)

    Xu, Liukang; Burba, George; Schedlbauer, Jessica; Zona, Donatella; McDermitt, Dayle K.; Anderson, Tyler; Oberbauer, Steven; Oechel, Walter; Komissarov, Anatoly; Riensche, Brad

    2010-05-01

    Majority of natural methane production happens at remote unpopulated areas in ecosystems with little or no infrastructure or easily available grid power, such as arctic and boreal wetlands, tropical mangroves, etc. Present approaches for direct measurements of CH4 fluxes rely on fast closed-path analyzers, which have to work under significantly reduced pressures, and require powerful pumps and grid power. Power and labor demands may be reasons why CH4 flux is often measured at locations with good infrastructure and grid power, and not with high CH4 production. An instrument was developed to allow Eddy Covariance measurements of CH4 flux with power consumption 30-150 times below presently available technologies. This instrument, LI-7700, uses <10W of power, and can easily be run on solar panel, or with small portable generator, while present technologies require 300-1500 Watts of the grid power. The proposed extremely low-power technology would allows placing methane Eddy Covariance stations in the middle of the source (wetland, rice paddy, forest, etc.) in the absence of the grid power. This could significantly expand the Eddy Covariance CH4 flux measurements coverage, and possibly, significantly improve the budget estimates of world CH4 emissions and budget. Various prototypes of the LI-7700 were field-tested for three seasons at the remote site in middle of Everglades National Park (Florida, USA) using solar panels, at three stationary and several mobile sites during three seasons at remote Arctic wetlands near Barrow (Alaska, USA), in the tropical mangroves near La Paz (Mexico) using portable generator, and in bare agricultural field near Mead (Nebraska, USA) during 2005 through 2010. Latest data on CH4 concentration, co-spectra and fluxes, and latest details of instrumental design are examined in this presentation. Overall, hourly methane fluxes ranged from near-zero at night to about 4 mg m-2 h-1 in midday in arctic tundra. Observed fluxes were within the

  6. In Vivo Measurements Of Coronary Blood Volumi By Dye And Inert Gas Dilution Technic

    NASA Astrophysics Data System (ADS)

    Hoeft, A.; Korb, H.; Wolpers, H. G.

    1984-10-01

    The application of a double fiberoptic device for measurements of arterial and coronary venous dye dilution curves facilitates the determination of coronary mean transit times even under clinical conditions. Since the dye, indocyanine green, is an intravascular tracer, the calculation of tissue blood flow would be possible if the intracoronary blood volume per unit of muscular weight is known. This study was therefore designed to investigate the physiologic range and the influence of coronary vasodilation and different hemodynamic conditions on the amount of myocardial blood volume. All experiments were carried out on anaesthetized close chest mongrel dogs in heart catheterization technic. Myocardial preload, afterload and inotropism and coronary vascular tone were varied by induction of hypo-, normo- and hypervolemia as well as by intravenous application of catecholamines, 13-blocking agents and vasodilating drugs. The determination of coronary blood volume was based on arterial and coronary venous kinetics of the intravascular tracer indocyanine green and the freely diffusible tracers helium and argon. Simultaneous measurements of the dye and the inert gases were obtained by a double fiberoptic system and a twin mass spectrometer, respectively. The intravascular and the tissue mean transit times as well as the coronary blood volume per unit of tissue weight were computed from the impulse response functions obtained by numerical deconvolution of the arterial and coronary venous indicator dilution curves. In contrast to reports of other authors coronary blood volume did not increase to a major extend during coronary vasodilation or elevated afterload. These new results suggest that the variation of coronary blood volume described in the literature is mainly due to methodological errors resulting from monoexponential extrapolation and distortion of the dye signal by the sampling catheter. These systematic errors, which, in particular, lead to an overestimation of

  7. A NOx and SO2 gas analyzer using deep-UV and violet light-emitting diodes for continuous emissions monitoring systems

    NASA Astrophysics Data System (ADS)

    Higashi, Ryoichi; Taniguchi, Yu; Akao, Kozo; Koizumi, Kazuhiro; Hirayama, Noritomo; Nakano, Yoshiaki

    2014-02-01

    A nitrogen oxides (NOx) and sulfur dioxide (SO2) gas analyzer using deep ultraviolet (DUV) and violet light- emitting diodes (LEDs) is developed. The LEDs with wavelengths of 280 nm and 400 nm were alternately turned on to detect SO2 and nitrogen dioxide (NO2) absorption. Nitric oxide (NO) was converted to NO2 with an ozonizer. In order to reduce water interference caused by water adsorption onto an inner surface of a gas ow cell, collimating optics reducing re ected lights were designed. As a result, less than 1% by full scale (%F.S.) of uctuation, 2%F.S. of drift and 0.5%F.S. of water interference were achieved in 0-50 ppm concentration range. Conversion efficiency from NO to NO2 was over 95%.

  8. Development and operation of an integrated sampling probe and gas analyzer for turbulent mixing studies in complex supersonic flows

    NASA Astrophysics Data System (ADS)

    Wiswall, John D.

    -temporal characteristic scales of the flow on the resulting time-area-averaged concentration measurements. Two series of experiments were performed to verify the probe's design; the first used Schlieren photography and verified that the probe sampled from the supersonic flowfield isokinetically. The second series involved traversing the probe across a free mixing layer of air and helium, to obtain both mean concentration and high frequency measurements. High-frequency data was statistically analyzed and inspection of the Probability Density Function (PDF) of the hot-film response was instrumental to interpret how well the resulting average mixing measurements represent these types of complex flows. The probe is minimally intrusive, has accuracy comparable to its predecessors, has an improved frequency response for mean concentration measurements, and samples from a very small area in the flowfield.

  9. Determination of antidepressants in human postmortem blood, brain tissue, and hair using gas chromatography-mass spectrometry.

    PubMed

    Wille, Sarah M R; De Letter, Els A; Piette, Michel H A; Van Overschelde, Lien K; Van Peteghem, Carlos H; Lambert, Willy E

    2009-11-01

    A gas chromatographic-mass spectrometric (GC-MS) method in positive ion chemical ionization mode in combination with a solid phase extraction was optimized for new-generation antidepressants and their metabolites in postmortem blood, brain tissue, and hair. Twelve antidepressants and their active metabolites (i.e., mirtazapine, viloxazine, venlafaxine, citalopram, mianserin, reboxetine, fluoxetine, fluvoxamine, sertraline, maprotiline, melitracen, paroxetine, desmethylfluoxetine, desmethylmianserin, desmethylmirtazapine, desmethylsertraline, desmethylmaprotiline, desmethylcitalopram, and didesmethylcitalopram) could be quantified. In this article, in addition to the validation of the GC-MS method, four postmortem cases are discussed to demonstrate the usefulness of the described method in forensic toxicology. In these cases, sertraline, fluoxetine, citalopram, and trazodone in combination with their active metabolites were quantified. Blood concentrations ranged from subtherapeutic to toxic concentrations, while brain to plasma ratios ranged from 0.8 to 17. Hair concentrations ranged from 0.4 to 2.5 ng/mg depending on the compound and hair segment. PMID:18839201

  10. In vivo support for the new concept of pulmonary blood flow-mediated CO2 gas excretion in the lungs.

    PubMed

    Kawai, Yoshiko; Ajima, Kumiko; Kaidoh, Maki; Sakaguchi, Masao; Tanaka, Satoshi; Kawamata, Mikito; Kimura, Hiroko; Ohhashi, Toshio

    2015-06-15

    To further examine the validity of the proposed concept of pulmonary blood flow-dependent CO2 gas excretion in the lungs, we investigated the effects of intramediastinal balloon catheterization-, pulmonary artery catheterization-, or isoprenaline (ISP)-induced changes in pulmonary blood flow on the end-expiratory CO2 gas pressure (PeCO2 ), the maximal velocity of the pulmonary artery (Max Vp), systemic arterial pressure, and heart rate of anesthetized rabbits. We also evaluated the changes in the PeCO2 in clinical models of anemia or pulmonary embolism. An almost linear relationship was detected between the PeCO2 and Max Vp. In an experiment in which small pulmonary arteries were subjected to stenosis, the PeCO2 fell rapidly, and the speed of the reduction was dependent on the degree of stenosis. ISP produced significant increases in the PeCO2 of the anesthetized rabbits. Conversely, treatment with piceatannol or acetazolamide induced significant reductions in the PeCO2 . Treatment with a cell surface F1/FO ATP synthase antibody caused significant reductions in the PeCO2 itself and the ISP-induced increase in the PeCO2 . Neither the PeCO2 nor SAP was significantly influenced by marked anemia [%hematocrit (Ht), 70 ∼ 47%]. On the other hand, in the presence of less severe anemia (%Ht: 100 ∼ 70%) both the PeCO2 and SAP fell significantly when the rabbits' blood viscosity was decreased. The rabbits in which pulmonary embolisms were induced demonstrated significantly reduced PeCO2 values, which was compatible with the lowering of their Max Vp. In conclusion, we reaffirm the validity of the proposed concept of CO2 gas exchange in the lungs. PMID:25888575

  11. Blood protein concentrations in the first two postnatal weeks associated with early postnatal blood gas derangements among infants born before the 28th week of gestation. The ELGAN Study

    PubMed Central

    Leviton, Alan; Allred, Elizabeth N.; Kuban, Karl C. K.; Dammann, Olaf; Fichorova, Raina N; O’Shea, T. Michael; Paneth, Nigel

    2016-01-01

    Aim To explore the relationships between blood gas derangements and blood concentrations of inflammation-related proteins shortly after preterm birth. Design Observational cohort Setting 14 neonatal intensive care units Subjects 734 infants born before the 28th week of gestation who were classified by their blood gas derangements during the first three postnatal days and by the concentrations of 25 proteins in their blood on days 1, 7, and 14. We classified these newborns by whether or not they had a highest or lowest PaO2, PCO2, and lowest pH in the most extreme quartile, and by whether or not they had a protein concentration in the highest quartile. Results Blood gas derangements on two days were much more likely to be accompanied or followed by sustained or recurrent systemic inflammation than a derangement on only one day. This was most evident for acidemia, and slightly less so for hypercapnia. Conclusions Our finding that protein concentration patterns indicative of systemic inflammation are associated with several blood gas derangements raises the possibility that organ damage attributed to these derangements might be accompanied by or involve an inflammatory response. PMID:21821429

  12. Endoscopic measurements of canine colonic mucosal blood flow using hydrogen gas clearance

    SciTech Connect

    Soybel, D.I.; Wan, Y.L.; Ashley, S.W.; Yan, Z.Y.; Ordway, F.S.; Cheung, L.Y.

    1987-04-01

    We have examined the feasibility of hydrogen (H/sub 2/) clearance for endoscopic measurements of colonic mucosal blood flow in anesthetized dogs. In 6 animals, measurements of H2 clearance did not differ significantly in different regions of the sigmoid colon and they were highly reproducible on different days. In a total of 12 dogs, measurements of H2 clearance correlated closely with those obtained using radioactive microspheres under resting conditions and, in 4 dogs, during infusion of vasopressin. In 8 dogs, ligation of the major arteries supplying the sigmoid colon resulted in an acute 60% decrease in sigmoid mucosal blood flow; however, in 5 animals that survived the procedure, mucosal blood flow returned nearly to control levels as early as 3 days after operation. Endoscopic H/sub 2/ clearance thus appears to be feasible for measuring mucosal blood flow in the colon. Serial measurements of H/sub 2/ clearance may prove useful in characterizing the role of mucosal blood flow in the pathogenesis of various forms of human colonic disease.

  13. Screening for and validated quantification of phenethylamine-type designer drugs and mescaline in human blood plasma by gas chromatography/mass spectrometry.

    PubMed

    Habrdova, Vilma; Peters, Frank T; Theobald, Denis S; Maurer, Hans H

    2005-06-01

    In recent years, several newer designer drugs of the so-called 2C series such as 2C-D, 2C-E, 2C-P, 2C-B, 2C-I, 2C-T-2, and 2C-T-7 have entered the illicit drug market as recreational drugs. Some fatal intoxications involving 2C-T-7 have been reported. Only scarce data have been published about analyses of these substances in human blood and/or plasma. This paper describes a method for screening and simultaneous quantification of the above-mentioned compounds and their analog mescaline in human blood plasma. The analytes were analyzed by gas chromatography/mass spectrometry in the selected-ion monitoring mode, after mixed-mode solid-phase extraction (HCX) and derivatization with heptafluorobutyric anhydride. The method was fully validated according to international guidelines. Validation data for 2C-T-2 and 2C-T-7 were unacceptable. For all other analytes, the method was linear from 5 to 500 microg/L and the data for accuracy (bias) and precision (coefficient of variation) were within the acceptance limits of +/-15% and <15%, respectively (within +/-20% and <20% near the limit of quantification of 5 microg/L). PMID:15827969

  14. Volcanic Plume Degassing of CO2: High Resolution Analysis With a Multi-Sensor gas Analyzer, and Applications to Etna, Stromboli and Vulcano Island (Italy)

    NASA Astrophysics Data System (ADS)

    Aiuppa, A.; Federico, C.; Giudice, G.; Gurrieri, S.

    2005-12-01

    The acquisition of high-resolution time series of CO2 emissions from active volcanoes is a challenge of current volcanic gas research. Recently, we have developed a field-portable gas analyzer, allowing the real-time measurement of CO2 and SO2 in volcanic plumes (Aiuppa et al., 2005). The gas analyzer integrates an IR spectrometer (for CO2), an electrochemical sensor specific to SO2, and a data-logger board enabling data capture, analysis and logging with a 3s time step. At open conduit volcanoes (Etna and Stromboli), the gas analyzer was used for the real time monitoring of CO2 and SO2 concentrations in the near-vent volcanic plumes. At Etna, the CO2 to SO2 ratio was relatively constant in the short term (on time scales of hours), while displaying larger fluctuations over longer periods: the CO2 to SO2 ratio ranged 2.2 to 10.8 during passive degassing over September 2004-August 2005. The highest CO2 to SO2 ratio were interpreted as due to degassing of more primitive CO2-rich magmas feeding the shallow volcano plumbing system. At Stromboli, high-frequency variations were observed, with the CO2 to SO2 ratio fluctuating from 8-14 during passive degassing to 25-35 during strombolian explosions. At both volcanoes, combining of these data with high-frequency DOAS determinations of SO2 output rates will provide the real time determination of CO2 output rates. At Vulcano Island, the gas analyzer was exposed to gas effluents released from several tenths of fumaroles (for a minimum of 30 determinations at any given fumarole and for each species over an observation period of 90s). This allowed defining the chemical structure and heterogeneity of the fumarole field in terms of the CO2 to SO2 ratio (H2S was also measured by specific electrochemical sensor). The main degassing fumaroles (T > 150°C) had an average CO2/(SO2+H2S) molar ratios of 35, while S-poor compositions (CO2/(SO2+H2S) > 50) characterized the field margins, probably due to deposition of native sulfur. The

  15. GC-NPD and GC-MS analysis of preserved tissue of Bhopal gas disaster: evidence of methyl carbamylation in post-mortem blood.

    PubMed

    Sriramachari, S; Rao, G J; Sharma, V K; Jadhav, R K; Saraf, A K; Chandra, H

    1991-10-01

    Twenty-five preserved autopsy blood samples of Bhopal toxic gas exposed victims were analysed by gas chromatography (GC) coupled with either Nitrogen-Phosphorous detector (NPD) or mass spectrometer (MS) for the presence of methyl carbamyl valine in terms of valine methyl hydantoin (VMH). 84% of these samples showed a positive test for VMH on GC-NPD and the identity of the peaks were further confirmed on GC-MS. The concentration of VMH in the gas-affected positive blood samples ranged from 2.56 to 51.28 nanomoles. These results indicate entry of methyl isocyanate (MIC), one of the constituents of the toxic cloud caused by the disaster, into the blood stream of victims who had inhaled gas. PMID:1795610

  16. The effects of a history of seizures during pregnancy on umbilical arterial blood gas values in pregnant women with epilepsy

    PubMed Central

    Özdemir, Özhan; Sarı, Mustafa Erkan; Ertuğrul, Funda Arpacı; Kurt, Aslıhan; Selimova, Vefa; Atalay, Cemal Reşat

    2014-01-01

    Objective The objective of this study is to investigate if the number of seizures that occur during pregnancy has any effect on umbilical arterial blood gas values at delivery. Material and Methods In total, 55 women who were 37 to 41 weeks pregnant and diagnosed with generalized tonic-clonic epilepsy and 50 pregnant women with similar characteristics but not diagnosed as epileptic were included in this study. The patients diagnosed with epilepsy were divided into two groups: 27 patients with a history of at least 5 epileptic seizures during pregnancy and 28 who had no seizures during pregnancy. All patients diagnosed with epilepsy had a history of caesarean delivery or a caesarean section under general anesthesia on the advice of neurology. Pregnant women in the control group were also chosen from among patients who had a caesarean on account of a previous caesarean delivery. In the cases included in the study, umbilical arterial blood gas sampling was performed immediately after delivery. Results When the control group without epilepsy was compared with pregnant women who had no history of epileptic seizures during pregnancy, no difference was found in umbilical arterial blood gas values (p>0.05). When patients with a history of 5 or more epileptic seizures during pregnancy were compared with the control group without epilepsy and the patients with epilepsy who had no history of seizures during pregnancy, there was no statistically significant difference (p>0.05), although their umbilical arterial blood pH values were found to be lower, while partial carbon dioxide pressure (pCO2), values were higher and partial oxygen pressure (pO2) values were lower. Conclusion Taking potential fetal risks into consideration, maternal generalized tonic-clonic epileptic seizures might be worrying. Tonic-clonic seizures that occur during pregnancy appear to be associated with temporary hypoxia. Therefore, monotherapy for seizures and treatment at the lowest effective dose should

  17. Comprehensive size-determination of whole virus vaccine particles using gas-phase electrophoretic mobility macromolecular analyzer, atomic force microscopy, and transmission electron microscopy.

    PubMed

    Havlik, Marlene; Marchetti-Deschmann, Martina; Friedbacher, Gernot; Winkler, Wolfgang; Messner, Paul; Perez-Burgos, Laura; Tauer, Christa; Allmaier, Günter

    2015-09-01

    Biophysical properties including particle size distribution, integrity, and shape of whole virus vaccine particles at different stages in tick-borne encephalitis (TBE) vaccines formulation were analyzed by a new set of methods. Size-exclusion chromatography (SEC) was used as a conservative sample preparation for vaccine particle fractionation and gas-phase electrophoretic mobility macromolecular analyzer (GEMMA) for analyzing electrophoretic mobility diameters of isolated TBE virions. The derived particle diameter was then correlated with molecular weight. The diameter of the TBE virions determined after SEC by GEMMA instrumentation was 46.8 ± 1.1 nm. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) were implemented for comparison purposes and to gain morphological information on the virion particle. Western blotting (Dot Blot) as an immunological method confirmed biological activity of the particles at various stages of the developed analytical strategy. AFM and TEM measurements revealed higher diameters with much higher SD for a limited number of virions, 60.4 ± 8.5 and 53.5 ± 5.3 nm, respectively. GEMMA instrumentation was also used for fractionation of virions with specifically selected diameters in the gas-phase, which were finally collected by means of an electrostatic sampler. At that point (i.e., after particle collection), AFM and TEM showed that the sampled virions were still intact, exhibiting a narrow size distribution (i.e., 59.8 ± 7.8 nm for AFM and 47.5 ± 5.2 nm for TEM images), and most importantly, dot blotting confirmed immunological activity of the collected samples. Furthermore dimers and virion artifacts were detected, too. PMID:26266988

  18. Development, validation and application of a method to analyze phenols in water samples by solid phase micro extraction-gas chromatography-flame ionization detector.

    PubMed

    Lanças, Fernando M; Olivares, Igor R B; Alves, Priscila M

    2007-01-01

    In this work the development, validation and application of method using Solid Phase Microexctration (SPME) for the analyses of five pollutants (phenol, 2-nitrophenol, 2,4-dimethylphenol, 2,4-dichlorophenol and 4-chloro, 3-methyl phenol) in supplying water, using gas chromatography (GC) with flame ionization detector (FID) is described. The optimal conditions obtained for SPME were: fiber type: Poliacrylate (PA); extraction time: 40 minutes; extraction temperature: 70 degrees C; amount of salt added to sample (NaCl): 15%; desorption temperature: 8 minutes. The parameters studied in the method validation were: limit of detection (0.3 and 3.5 microg.L(- 1)); precision, measured by the variation coefficient (between 2.1 and 8.8%); calibration curve and linearity, by using the external standardization method (between 1 and 50 50 microg.L(- 1)). After the methodology development, samples of water collected in Atibaia River (São Paulo - Brazil) were analyzed, using the optimized methodology. Three water samples collected in the rain season showed a peak with retention time close to 4-chloro, 3 methyl phenol further analyzed by Gas Chromatography-Mass Spectrometry for the identity confirmation. In spite of the fact that none target compounds were found in the river water samples analyzed, the presence of two phenols different from those investigated (p-terc butyl phenol; butylated hydroxytoluene) were detected. These results together with the results of the limit of detection (that showed to be lower than the maximum concentration of phenols demanded by different environment control agencies), and the results of the validation, indicate the applicability of this method for the analysis of selected phenols in river water samples. PMID:17562456

  19. Comprehensive Size-Determination of Whole Virus Vaccine Particles Using Gas-Phase Electrophoretic Mobility Macromolecular Analyzer, Atomic Force Microscopy, and Transmission Electron Microscopy

    PubMed Central

    Havlik, Marlene; Marchetti-Deschmann, Martina; Friedbacher, Gernot; Winkler, Wolfgang; Messner, Paul; Perez-Burgos, Laura; Tauer, Christa; Allmaier, Günter

    2015-01-01

    Biophysical properties including particle size distribution, integrity, and shape of whole virus vaccine particles at different stages in tick-borne encephalitis (TBE) vaccines formulation were analyzed by a new set of methods. Size-exclusion chromatography (SEC) was used as a conservative sample preparation for vaccine particle fractionation and gas-phase electrophoretic mobility macromolecular analyzer (GEMMA) for analyzing electrophoretic mobility diameters of isolated TBE virions. The derived particle diameter was then correlated with molecular weight. The diameter of the TBE virions determined after SEC by GEMMA instrumentation was 46.8 ± 1.1 nm. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) were implemented for comparison purposes and to gain morphological information on the virion particle. Western blotting (Dot Blot) as an immunological method confirmed biological activity of the particles at various stages of the developed analytical strategy. AFM and TEM measurements revealed higher diameters with much higher SD for a limited number of virions, 60.4 ± 8.5 and 53.5 ± 5.3 nm, respectively. GEMMA instrumentation was also used for fractionation of virions with specifically selected diameters in the gas-phase, which were finally collected by means of an electrostatic sampler. At that point (i.e., after particle collection), AFM and TEM showed that the sampled virions were still intact, exhibiting a narrow size distribution (i.e., 59.8 ± 7.8 nm for AFM and 47.5 ± 5.2 nm for TEM images), and most importantly, dot blotting confirmed immunological activity of the collected samples. Furthermore dimers and virion artifacts were detected, too. PMID:26266988

  20. Maternal and fetal arterial blood gas data during general anaesthesia for caesarean delivery of preterm twin lambs.

    PubMed

    Musk, G C; Kemp, M W

    2016-06-01

    Much remains to be understood with regards the effects of prolonged anaesthesia on maternal and fetal haemodynamics and oxygenation. With the aim of improving anaesthetic management of pregnant sheep undergoing recovery surgery under anaesthesia, paired maternal and fetal arterial blood samples were collected during caesarean delivery of twin preterm lambs to document the blood gas status of the ewe and fetus. Twenty-one Merino twin pregnant ewes at 126 (±1) days of gestation were anaesthetized for caesarean delivery of their fetuses. Arterial blood samples were collected from the radial artery of the ewe and umbilical artery of the fetus at the point of delivery. There was a significant difference between maternal PaCO2 and end-tidal CO2 and alveolar and arterial PaO2, indicating ventilation perfusion mismatch. Interestingly, the ewes were anaemic but the fetuses were not. These data underscore the need to undertake further work to determine the optimal anaesthetic regimen for twin pregnant ewes at different gestational ages in a biomedical research setting. PMID:26219550

  1. A validated method for the analysis of cannabinoids in post-mortem blood using liquid-liquid extraction and two-dimensional gas chromatography-mass spectrometry.

    PubMed

    Andrews, Rebecca; Paterson, Sue

    2012-10-10

    A validated method for the identification and quantification of Δ(9)-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabinol (CBN), 11-hydroxy-Δ(9)-tetrahydrocannabinol (11-OH-THC) and 11-nor-Δ(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in post-mortem blood specimens is described. Liquid-liquid extraction was used to extract the cannabinoids from 1 mL of post-mortem blood. The extracts were derivatized with N-methyl-N-(trimethylsilyl)trifluoroacetamide. The final derivatized extracts were analyzed using two-dimensional gas chromatography-mass spectrometry. The limit of detection was 0.25 ng/mL for all analytes and the limit of quantification of the assay was 0.25 ng/mL for THC, CBN, 11-OH-THC and 0.5 ng/mL for CBD and THC-COOH. The assay was linear across the concentration range 0.25-50 ng/mL (determined with a low and a high calibration range) with correlation coefficients ≥0.992 for all analytes. Inter-day and intra-day accuracy was within ±15% of the target concentration for all analytes. The co-efficients of variation (%CV) for inter-day and intra-day precision were ≤12% for all analytes. The extraction efficiency was >73% for all analytes. The method has successfully been applied to 54 post-mortem blood specimens to date. To the authors knowledge this is the first validated 2D GC-MS method for the analysis of THC, CBD, CBN, 11-OH-THC and THC-COOH following LLE and its application to post-mortem specimens. PMID:22717553

  2. Establishment of Age- and Gender-Specific Reference Ranges for 36 Routine and 57 Cell Population Data Items in a New Automated Blood Cell Analyzer, Sysmex XN-2000

    PubMed Central

    Park, Sang Hyuk; Lee, Bo-Ra; Kim, Mi-Jeong; Han, Min-Young; Cho, Young-Uk; Jang, Seongsoo

    2016-01-01

    We established age- and gender-specific reference ranges for the 36 routine complete blood cell (CBC) and 57 cell population data (CPD) items in the Sysmex XN-2000 (Sysmex, Japan). In total, 280 peripheral blood samples were obtained from an equal number of healthy adults. Values for 36 routine items and 57 CPD items were obtained for each sample, and the results were categorized into six subgroups (N>39 in each subgroup) according to patient age (20-40, 41-60, and >60 yr) and gender (male and female), and compared with respect to age and gender differences. The majority of data items (22 of 36 routine CBC items and 44 of 57 CPD items) exhibited significant differences (P≤0.05) in their results with respect to age or gender, and several red cell-, lymphocyte-, and platelet-related data tended to decrease in women or older adults. These results provide a basis for establishing age- and gender-specific reference ranges for routine and CPD items in Sysmex XN-2000. Furthermore, these reference ranges could be used to determine clinical significance for new items of Sysmex XN-2000 in further studies. PMID:26915613

  3. Membrane oxygenator heat exchanger failure detected by unique blood gas findings.

    PubMed

    Hawkins, Justin L

    2014-03-01

    Failure of components integrated into the cardiopulmonary bypass circuit, although rare, can bring about catastrophic results. One of these components is the heat exchanger of the membrane oxygenator. In this compartment, unsterile water from the heater cooler device is separated from the sterile blood by stainless steel, aluminum, or by polyurethane. These areas are glued or welded to keep the two compartments separate, maintaining sterility of the blood. Although quality control testing is performed by the manufacturer at the factory level, transport presents the real possibility for damage. Because of this, each manufacturer has included in the instructions for use a testing procedure for testing the integrity of the heat exchanger component. Water is circulated through the heat exchanger before priming and a visible check is made of the oxygenator bundle to check for leaks. If none are apparent, then priming of the oxygenator is performed. In this particular case, this procedure was not useful in detecting communication between the water and blood chambers of the oxygenator. PMID:24779125

  4. A sportomics strategy to analyze the ability of arginine to modulate both ammonia and lymphocyte levels in blood after high-intensity exercise

    PubMed Central

    2012-01-01

    Background Exercise is an excellent tool to study the interactions between metabolic stress and the immune system. Specifically, high-intensity exercises both produce transient hyperammonemia and influence the distribution of white blood cells. Carbohydrates and glutamine and arginine supplementation were previously shown to effectively modulate ammonia levels during exercise. In this study, we used a short-duration, high-intensity exercise together with a low carbohydrate diet to induce a hyperammonemia state and better understand how arginine influences both ammonemia and the distribution of leukocytes in the blood. Methods Brazilian Jiu-Jitsu practitioners (men, n = 39) volunteered for this study. The subjects followed a low-carbohydrate diet for four days before the trials and received either arginine supplementation (100 mg·kg-1 of body mass·day-1) or a placebo. The intergroup statistical significance was calculated by a one-way analysis of variance, followed by Student’s t-test. The data correlations were calculated using Pearson’s test. Results In the control group, ammonemia increased during matches at almost twice the rate of the arginine group (25 mmol·L-1·min-1 and 13 μmol·L-1·min-1, respectively). Exercise induced an increase in leukocytes of approximately 75%. An even greater difference was observed in the lymphocyte count, which increased 2.2-fold in the control group; this increase was partially prevented by arginine supplementation. The shape of the ammonemia curve suggests that arginine helps prevent increases in ammonia levels. Conclusions These data indicate that increases in lymphocytes and ammonia are simultaneously reduced by arginine supplementation. We propose that increased serum lymphocytes could be related to changes in ammonemia and ammonia metabolism. PMID:22734448

  5. Optimization of an enclosed gas analyzer sampling system for measuring eddy covariance fluxes of H2O and CO2

    DOE PAGESBeta

    Metzger, Stefan; Burba, George; Burns, Sean P.; Blanken, Peter D.; Li, Jiahong; Luo, Hongyan; Zulueta, Rommel C.

    2016-03-31

    Several initiatives are currently emerging to observe the exchange of energy and matter between the earth's surface and atmosphere standardized over larger space and time domains. For example, the National Ecological Observatory Network (NEON) and the Integrated Carbon Observing System (ICOS) are set to provide the ability of unbiased ecological inference across ecoclimatic zones and decades by deploying highly scalable and robust instruments and data processing. In the construction of these observatories, enclosed infrared gas analyzers are widely employed for eddy covariance applications. While these sensors represent a substantial improvement compared to their open- and closed-path predecessors, remaining high-frequency attenuation variesmore » with site properties and gas sampling systems, and requires correction. Here, we show that components of the gas sampling system can substantially contribute to such high-frequency attenuation, but their effects can be significantly reduced by careful system design. From laboratory tests we determine the frequency at which signal attenuation reaches 50 % for individual parts of the gas sampling system. For different models of rain caps and particulate filters, this frequency falls into ranges of 2.5–16.5 Hz for CO2, 2.4–14.3 Hz for H2O, and 8.3–21.8 Hz for CO2, 1.4–19.9 Hz for H2O, respectively. A short and thin stainless steel intake tube was found to not limit frequency response, with 50 % attenuation occurring at frequencies well above 10 Hz for both H2O and CO2. From field tests we found that heating the intake tube and particulate filter continuously with 4 W was effective, and reduced the occurrence of problematic relative humidity levels (RH > 60 %) by 50 % in the infrared gas analyzer cell. No further improvement of H2O frequency response was found for heating in excess of 4 W. These laboratory and field tests were reconciled using resistor–capacitor theory, and NEON's final gas sampling system was

  6. Development and diagnostics of revised ion beam analyzer, ion or laser produced plasmas and X-ray pre-ionizer for gas lasers

    SciTech Connect

    Kasuya, K.; Watanabe, M.; Kamiya, T.; Nishigori, K.; Funatsu, M.; Ido, D.; Ebine, T.; Okayama, H.; Sunami, H.; Wu, C.; Adachi, T.; Hotta, E.; Hattori, T.; Yasuike, K.; Nakai, S.; Miyamoto, S.

    1997-04-15

    A CCD element was tested as an end plate of a Thomson parabola analyzer. This element was directly irradiated by ion beams to produce electric signals associated with the beams. With a pin-hole camera, we also tried to measure the divergence angle of ion beams. Coated thin layers of ion source materials on a quartz plate were back-lighted by an e-beam pumped KrF laser, and the produced plasmas were observed to supply advanced source plasmas for pulsed ion diodes. We built a cryogenic target which was cooled by liquid nitrogen, and the ice-covered target was irradiated by proton beams to measure the concerned ablation processes. Fundamental characteristics of an X-ray source with wire-initiated discharge plasmas for pre-ionization of gas mixtures of our former discharge-pumped KrF laser in place of UV pre-ionization were also investigated.

  7. Surface CHEMKIN (Version 4. 0): A Fortran package for analyzing heterogeneous chemical kinetics at a solid-surface---gas-phase interface

    SciTech Connect

    Coltrin, M.E. ); Kee, R.J.; Rupley, F.M. )

    1991-07-01

    Heterogeneous reaction at the interface between a solid surface and adjacent gas is central to many chemical processes. Our purpose for developing the software package SURFACE CHEMKIN was motivated by our need to understand the complex surface chemistry in chemical vapor deposition systems involving silicon, silicon nitride, and gallium arsenide. However, we have developed the approach and implemented the software in a general setting. Thus, we expect it will find use in such diverse applications as chemical vapor deposition, chemical etching, combustion of solids, and catalytic processes, and for a wide range of chemical systems. We believe that it provides a powerful capability to help model, understand, and optimize important industrial and research chemical processes. The SURFACE CHEMKIN software is designed to work in conjunction with the CHEMKIN-2 software, which handles the chemical kinetics in the gas phase. It may also be used in conjunction with the Transport Property Package, which provides information about molecular diffusion. Thus, these three packages provide a foundation on which a user can build applications software to analyze gas-phase and heterogeneous chemistry in flowing systems. These packages should not be considered programs'' in the ordinary sense. That is, they are not designed to accept input, solve a particular problem, and report the answer. Instead, they are software tools intended to help a user work efficiently with large systems of chemical reactions and develop Fortran representations of systems of equations that define a particular problem. It is up the user to solve the problem and interpret the answer. 11 refs., 15 figs., 5 tabs.

  8. Long-term Calibration Strategy for the Earth Networks CO2 and CH4 Sensor Network in Urban and Background Sites Using the Picarro CRDS Gas Analyzer

    NASA Astrophysics Data System (ADS)

    Welp, L. R.; Lueker, T.; Kim, J.; Salameh, P.; Walker, S.; Keeling, R. F.; Weiss, R. F.; Sloop, C.; Callahan, W.; Bixler, D.; Long, A.

    2014-12-01

    The Earth Networks greenhouse-gas monitoring network initiated in 2010 has now expanded to nearly 35 stations across the United States. Building on this effort, the Megacities project funded by NIST has the goal of measuring CO2, CH4 and CO concentrations in the Los Angeles region to support quantitative emissions estimates. These efforts require precise concentration measurements that are internally consistent across the network so that small changes in concentration from one location to another are representative of emissions along the pathway. In this presentation, we examine the calibration strategy for these long-term monitoring efforts using data collected over the past few years. We will address the following issues as they apply to the Picarro G2301 CRDS CO2/CH4/H2O gas analyzer: (1) The frequency of calibration required. (2) The duration of calibration needed for the inlet system to stabilize. (3) The stability and linearity of the instrument span and options for monitoring with a high concentration tank or zero air tank in addition to an ambient concentration calibration tank. We will also outline the calibration tank overlap scheme employed to ensure a consistent long-term record of calibration.

  9. (Ca,Mg)-Carbonate and Mg-Carbonate at the Phoenix Landing Site: Evaluation of the Phoenix Lander's Thermal Evolved Gas Analyzer (TEGA) Data Using Laboratory Simulations

    NASA Technical Reports Server (NTRS)

    Sutter, B.; Ming, D. W.; Boynton, W. V.; Niles, P. B.; Morris, R. V.

    2011-01-01

    Calcium carbonate (4.5 wt. %) was detected in the soil at the Phoenix Landing site by the Phoenix Lander s The Thermal and Evolved Gas Analyzer [1]. TEGA operated at 12 mbar pressure, yet the detection of calcium carbonate is based on interpretations derived from thermal analysis literature of carbonates measured under ambient (1000 mbar) and vacuum (10(exp -3) mbar) conditions [2,3] as well as at 100 and 30 mbar [4,5] and one analysis at 12 mbar by the TEGA engineering qualification model (TEGA-EQM). Thermodynamics (Te = H/ S) dictate that pressure affects entropy ( S) which causes the temperature (Te) of mineral decomposition at one pressure to differ from Te obtained at another pressure. Thermal decomposition analyses of Fe-, Mg-, and Ca-bearing carbonates at 12 mbar is required to enhance the understanding of the TEGA results at TEGA operating pressures. The objectives of this work are to (1) evaluate the thermal and evolved gas behavior of a suite of Fe-, Mg-, Ca-carbonate minerals at 1000 and 12 mbar and (2) discuss possible emplacement mechanisms for the Phoenix carbonate.

  10. Role of blood gas analysis during cardiopulmonary resuscitation in out-of-hospital cardiac arrest patients

    PubMed Central

    Kim, Youn-Jung; Lee, You Jin; Ryoo, Seung Mok; Sohn, Chang Hwan; Ahn, Shin; Seo, Dong-Woo; Lim, Kyoung Soo; Kim, Won Young

    2016-01-01

    Abstract To determine the relationship between acid–base findings, such as pH, pCO2, and serum lactate levels, obtained immediately after starting cardiopulmonary resuscitation and the return of spontaneous circulation (ROSC). A prospective observational study of adult, nontraumatic out-of-hospital cardiac arrest (OHCA) patients was conducted at an urban academic teaching institution between April 1, 2013 and March 31, 2015. Arterial blood sample for acid–base data was taken from all OHCA patients on arrival to the emergency department. Of 224 OHCA patients, 88 patients with unavailable blood samples or delayed blood sampling or ROSC within 4 minutes were excluded, leaving 136 patients for analysis. The pH in the ROSC group was significantly higher than in the non-ROSC group (6.96 vs. 6.85; P = 0.009). pCO2 and lactate levels in the ROSC group were significantly lower than those in the non-ROSC group (74.0 vs. 89.5 mmHg, P < 0.009; 11.6 vs. 13.6 mmol/L, P = 0.044, respectively). In a multivariate regression analysis, pCO2 was the only independent biochemical predictor for sustained ROSC (OR 0.979; 95% CI 0.960–0.997; P = 0.025) and pCO2 of <75 mmHg was 3.3 times more likely to achieve ROSC (OR 0.302; 95% CI 0.146–0.627; P = 0.001). pCO2 levels obtained during cardiopulmonary resuscitation on ER arrival was associated with ROSC in OHCA patients. It might be a potentially marker for reflecting the status of the ischemic insult. These preliminary results need to be confirmed in a larger population. PMID:27336894

  11. Measurements of CO2 and H2O Fluxes with New Enclosed Design and with Modified Open-path Design of Fast Gas Analyzers

    NASA Astrophysics Data System (ADS)

    Burba, George; McDermitt, Dayle K.; Velgersdyk, Michael; Eckles, Robert; Anderson, Dan

    2010-05-01

    In this presentation two novel approaches to designing fast CO2/H2O gas analyzers (e.g., new enclosed short tube enabled design and modified open-path low temperature controlled design) are discussed in comparison with two conventional approaches (e.g., traditional closed-path and open-path designs) in terms of their field performance for Eddy Covariance flux measurements. Closed- and open-path designs of the fast gas analyzers are two well-established sampling cell configurations widely utilized for measurements of CO2 and H2O fluxes and concentrations. Each configuration has advantages and deficiencies. Open-path analyzers have excellent frequency response, long-term stability, and low sensitivity to window contamination. They are pump-free and require infrequent calibrations. Yet they are susceptible to data loss during precipitation and icing, and may need instrument surface heat flux correction when used in extremely cold conditions. Closed-path analyzers can collect data during precipitation, can be climate-controlled, and are not susceptible to surface heating issues. Yet they experience significant frequency loss in long intake tubes, especially problematic when computing water vapor flux. They may require frequent calibrations and need powerful pump. The study presents field data from an alternative new design: a compact enclosed CO2/H2O analyzer, the LI-7200, enabled for operation with short intake tube, intended to maximize strengths and to minimize weaknesses of both traditional open-path and closed-path designs. Also presented are data from a new open-path CO2/H2O gas analyzer, LI-7500A, based on the LI-7500 model modified to produce substantially less heat during extremely cold conditions. Four prototypes of LI-7200, were extensively field-tested in three experiments over contrasting ecosystems in 2006-2009. Instantaneous temperature fluctuations were attenuated, on average, by about 85-90% with 0.5 m intake tube, and by about 90-95% with 1 m intake

  12. Blood-gas and acid-base parameters in nontranquilized Arabian oryx (Oryx leucoryx) in the United Arab Emirates.

    PubMed

    Kilgallon, Conor; Bailey, Tom; Arca-Ruibal, Barbara; Misheff, Martha; O'Donovan, Declan

    2008-03-01

    Arterial and venous blood-gas and acid-base values were established from a herd (n = 19; 14 male, 5 female) of semi-free-ranging Arabian oryx (Oryx leucoryx) in the United Arab Emirates. The animals were restrained with the use of a modified raceway incorporating a commercially available handling crate. Statistically significant differences were found between arterial and venous values for PO2 (p < 0.001), PCO2 (p = 0.0141), SO2 (p < 0.001), pH (p = 0.0494), and glucose (p < 0.0001). The results are similar to those reported for the same species under field anesthetic conditions, and to those reported from other species of wild bovidae, both tranquilized and nontranquilized, established under similar methods of restraint. In addition, Bland and Altman plots suggest adequate levels of clinical agreement between venous and arterial pH but not between arterial and venous PCO2. PMID:18432091

  13. COMBINING THE STRENGTHS OF OPEN-PATH AND CLOSED-PATH DESIGNS INTO A SINGLE CO2/H2O GAS ANALYZER

    NASA Astrophysics Data System (ADS)

    Burba, G. G.; Furtaw, M.; McDermitt, D. K.; Eckles, R.

    2009-12-01

    Open-path and closed-path designs of the fast CO2/H2O gas analyzers are widely used to measure concentrations and fluxes. Both designs have their advantages and deficiencies. Open-path analyzers have excellent frequency response, long-term stability, and low sensitivity to window contamination. They are pump-free and require infrequent calibrations. Yet they are susceptible to data loss during precipitation and icing, and may need instrument surface heat flux correction when used in cold conditions. Closed-path analyzers can collect data during precipitation, can be climate-controlled, and are not susceptible to surface heating issues. Yet they experience significant frequency loss in long intake tubes, especially problematic when computing water vapor flux. They may require frequent calibrations and need powerful pump. Here we present preliminary data from third kind of a design: a compact enclosed CO2/H2O analyzer, the LI-7200, enabled for operation with short intake tube, intended to maximize strengths and to minimize weaknesses of both traditional open-path and closed-path designs. Four prototypes were extensively field-tested in three experiments over contrasting ecosystems in 2006-2009. Instantaneous temperature fluctuations were attenuated, on average, by about 85-90% with 0.5 m intake tube, and by about 90-95% with 1 m intake tube, minimizing sensible heat flux portion of Webb-Pearman-Leuning term. The remainder was measured directly eliminating open-path heating or any other temperature issues. Fast temperature and pressure measured inside the cell of LI-7200, and low sensitivity to window contamination allowed for the use of short intake tube (0.5-1.0 m or less), leading to a low power demand for the pump and entire system. The power demand of the tested blower with flow control was about 15 W, which is considerably less than that of traditional closed-path systems (about 50-100 W). Frequency losses for CO2 and H2O fluxes from LI-7200 were small, yet

  14. DIFFERENTIAL ANALYZER

    DOEpatents

    Sorensen, E.G.; Gordon, C.M.

    1959-02-10

    Improvements in analog eomputing machines of the class capable of evaluating differential equations, commonly termed differential analyzers, are described. In general form, the analyzer embodies a plurality of basic computer mechanisms for performing integration, multiplication, and addition, and means for directing the result of any one operation to another computer mechanism performing a further operation. In the device, numerical quantities are represented by the rotation of shafts, or the electrical equivalent of shafts.

  15. Fast gas chromatography and negative-ion chemical ionization tandem mass spectrometry for forensic analysis of cannabinoids in whole blood.

    PubMed

    Thomas, Aurélien; Widmer, Christèle; Hopfgartner, Gérard; Staub, Christian

    2007-11-01

    The present work describes a fast gas chromatography/negative-ion chemical ionization tandem mass spectrometric assay (Fast GC/NICI-MS/MS) for analysis of tetrahydrocannabinol (THC), 11-hydroxy-tetrahydrocannabinol (THC-OH) and 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH) in whole blood. The cannabinoids were extracted from 500 microL of whole blood by a simple liquid-liquid extraction (LLE) and then derivatized by using trifluoroacetic anhydride (TFAA) and hexafluoro-2-propanol (HFIP) as fluorinated agents. Mass spectrometric detection of the analytes was performed in the selected reaction-monitoring mode on a triple quadrupole instrument after negative-ion chemical ionization. The assay was found to be linear in the concentration range of 0.5-20 ng/mL for THC and THC-OH, and of 2.5-100 ng/mL for THC-COOH. Repeatability and intermediate precision were found less than 12% for all concentrations tested. Under standard chromatographic conditions, the run cycle time would have been 15 min. By using fast conditions of separation, the assay analysis time has been reduced to 5 min, without compromising the chromatographic resolution. Finally, a simple approach for estimating the uncertainty measurement is presented. PMID:17913432

  16. GC-MS identification of MIC trimer: a constituent of tank residue in preserved autopsy blood of Bhopal gas victims.

    PubMed

    Chandra, H; Rao, G J; Saraf, A K; Sharma, V K; Jadhav, R K; Sriramachari, S

    1991-10-01

    Based on the external and internal findings of Bhopal gas disaster victims, it was apparent that the gases and particulate matter came out as an aerosol. This was possibly the pyrolysed, reformulated, reconjugated suspension of constituents of the tank E-610 of Union Carbide India Limited, Bhopal, while it was claimed to be methyl isocyanate (MIC) only. It was postulated by the manufacturer of MIC, that the material inhaled by the victims of the Bhopal gas disaster does not cross the lung barrier (UCC press conference on 14th December 1984). It was observed that the more the victims ran, the more aerosol they inhaled and the fatalities were observed in such victims. The tissues, which were preserved in the deep freeze, were randomly selected and analysed by GC coupled with MS (ITD) Finnigan MAT, UK. 14 out of 34 autopsy cases showed MIC trimer peak in extracts of blood. This was one of the constituents of the aerosol and was also located in the tank residue, thereby proving that the trimer had passed the lung barrier. PMID:1795611

  17. Process Analyzer

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The ChemScan UV-6100 is a spectrometry system originally developed by Biotronics Technologies, Inc. under a Small Business Innovation Research (SBIR) contract. It is marketed to the water and wastewater treatment industries, replacing "grab sampling" with on-line data collection. It analyzes the light absorbance characteristics of a water sample, simultaneously detects hundreds of individual wavelengths absorbed by chemical substances in a process solution, and quantifies the information. Spectral data is then processed by ChemScan analyzer and compared with calibration files in the system's memory in order to calculate concentrations of chemical substances that cause UV light absorbance in specific patterns. Monitored substances can be analyzed for quality and quantity. Applications include detection of a variety of substances, and the information provided enables an operator to control a process more efficiently.

  18. Toxicity of carbon monoxide-hydrogen cyanide gas mixtures: Expose concentration, time-to-incapacitation, carboxyhemoglobin, and blood cyanide parameters. Final report

    SciTech Connect

    Sanders, D.C.; Chaturvedi, A.K.; Endecott, B.R.; Ritter, R.M.; Vu, N.

    1994-04-01

    During aircraft interior fires, carbon monoxide (CO) and hydrogen cyanide (HCN) are produced in sufficient amounts to cause incapacitation and death. Time-to-incapacitation (ti) is a practical parameter for estimating escape time in fire environments. Exposures to CO-HCN mixtures have demonstrated that these gases have additive effects (producing shorter times to incapacitation), but the resulting concentrations of carboxyhemoglobin (COHb) and blood cyanide (CN-) at incapacitation are not well defined. These undefined relationships between COHb and blood CN- levels and the onset of incapacitation make the interpretation of postmortem levels difficult for medical accident investigators. To explore these relationships, ti was determined in laboratory rats exposed to two CO-HCN mixtures consisting of CO and HCN concentrations that produce 5- and 35-min ti in individual gas exposures; COHb and blood CN- concentrations were determined at incapacitation. In the high concentration CO-HCN mixture, the resultant ti was shortened from 5 min to 2.6 min; COHb dropped from 81% to 55% and CN- from 2.3 microns/mL to 1.1 microns/mL. At the lower concentration COHCN mixture, where the resultant ti was reduced from 35 min to 11.1 min, COHb dropped from 71% to 61% and blood CN- decreased from 4.2 microns/mL to 1.1 microns/mL. Comparison of the COHb and blood CN- values with the values from our signal gas exposure studies indicated that any alteration of the uptake of either gas in blood by the presence of the other was minimal. These findings suggest that changes in COHb and blood CN- may not be directly correlated with the onset of incapacitation and that postmortem blood levels should be carefully evaluated, particularly when both gases are present.

  19. A Possible Organic Contribution to the Low Temperature CO2 Release Seen in Mars Phoenix Thermal and Evolved Gas Analyzer Data

    NASA Technical Reports Server (NTRS)

    Archer, P. D. Jr.; Lauer, H. V., Jr.; Sutter, B.; Ming, D. W.; Niles, P. B.; Boynton, W. V.

    2012-01-01

    Two of the most important discoveries of the Phoenix Mars Lander were the discovery of approx.0.6% perchlorate [1] and 3-5% carbonate [2] in the soils at the landing site in the martian northern plains. The Thermal and Evolved Gas Analyzer (TEGA) instrument was one of the tools that made this discovery. After soil samples were delivered to TEGA and transferred into small ovens, the samples could be heated up to approx.1000 C and the gases that evolved during heating were monitored by a mass spectrometer. A CO2 signal was detected at high temperature (approx.750 C) that has been attributed to calcium carbonate decomposition. In addition to this CO2 release, a lower temperature signal was seen. This lower temperature CO2 release was postulated to be one of three things: 1) desorption of CO2, 2) decomposition of a different carbonate mineral, or 3) CO2 released due to organic combustion. Cannon et al. [3] present another novel hypothesis involving the interaction of decomposition products of a perchlorate salt and calcium carbonate.

  20. Integrated Chemical and Microorganism Monitoring of Air Using Gas Chromatography/Ion Mobility Spectometry: Toward an Expanded-Use Volatile Organic Analyzer (VOA)

    NASA Technical Reports Server (NTRS)

    Eiceman, G. A.

    1999-01-01

    The work described in this research program originated with the choice by NASA of an ion mobility spectrometer for air quality monitoring on-board the international spacestation. Though the gas chromatograph-ion mobility spectrometer analyzer known as VOA met or exceeded expectations, limitations in the basic understanding of response and the utilization of foundational principles into usable technology was considered unacceptable. In this research program, a comprehensive model for the origins of mobility spectra was proposed, tested and verified. The principles considered responsible for the appearance of mobility spectra have now been elucidated through this project. This understanding has been applied in automated identification of mobility spectra using neural networks and routine procedures for this now exist. Finally, the limitation on linear range has been shown to be a technical limitation and not a fundamental limitation so that a hardware component was crafted to extend the linear range of a mobility spectrometer by 10X. This project has led to one Ph.D. dissertation and one MS thesis. In addition, over ten public presentations at professional meetings and six journal publications have resulted from this program of research. The findings are so plentiful that total analysis of the findings may require four to six years or more. The findings confirm that the decision to use VOA was sound and that the chemical and physical principles of mobility spectrometry are both understandable and predictable.

  1. Rapid and sensitive gas-chromatographic determination of caffeine in blood plasma, saliva, and xanthine beverages.

    PubMed

    Teeuwen, H W; Elbers, E L; van Rossum, J M

    1991-02-01

    A gas chromatographic procedure is reported for the determination of caffeine in plasma, saliva, and xanthine beverages. Using a 75 cm column packed with OV-17, nitrogen-sensitive detection, and 1 ml samples, a suitable limit of analysis (coefficient of variation (CV) = 10.2%) of 50 ng/ml was obtained in plasma. Within-day CVs at caffeine concentrations of 0.1-0.5-2.0-7.5-15.0 micrograms/ml in plasma were 7.7-5.6-4.8-3.8-3.4%, respectively. The limit of detection, defined as the injected quantity of caffeine giving rise to a signal to noise ratio of 2, is 40 pg, corresponding to a plasma concentration of 1 ng/ml. The procedure involves addition of the internal standard 7-pentyl theophylline and alkaline extraction of the sample with dichloromethane. The method described rivals any gaschromatographic assay published so far in rapidness and accuracy. Plasma and saliva caffeine concentrations were determined in a healthy male volunteer after swallowing 400 ml of coffee. The calculated pharmacokinetic parameters, assuming complete absorption of caffeine from the G.I. tract, agree well with previously published values. PMID:1875916

  2. Atmosphere Analyzer

    NASA Technical Reports Server (NTRS)

    1982-01-01

    California Measurements, Inc.'s model PC-2 Aerosol Particle Analyzer is produced in both airborne and ground-use versions. Originating from NASA technology, it is a quick and accurate method of detecting minute amounts of mass loadings on a quartz crystal -- offers utility as highly sensitive detector of fine particles suspended in air. When combined with suitable air delivery system, it provides immediate information on the size distribution and mass concentrations of aerosols. William Chiang, obtained a NASA license for multiple crystal oscillator technology, and initially developed a particle analyzer for NASA use with Langley Research Center assistance. Later his company produced the modified PC-2 for commercial applications Brunswick Corporation uses the device for atmospheric research and in studies of smoke particles in Fires. PC-2 is used by pharmaceutical and chemical companies in research on inhalation toxicology and environmental health. Also useful in testing various filters for safety masks and nuclear installations.

  3. Process Analyzer

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Under a NASA Small Business Innovation Research (SBIR) contract, Axiomatics Corporation developed a shunting Dielectric Sensor to determine the nutrient level and analyze plant nutrient solutions in the CELSS, NASA's space life support program. (CELSS is an experimental facility investigating closed-cycle plant growth and food processing for long duration manned missions.) The DiComp system incorporates a shunt electrode and is especially sensitive to changes in dielectric property changes in materials at measurements much lower than conventional sensors. The analyzer has exceptional capabilities for predicting composition of liquid streams or reactions. It measures concentrations and solids content up to 100 percent in applications like agricultural products, petrochemicals, food and beverages. The sensor is easily installed; maintenance is low, and it can be calibrated on line. The software automates data collection and analysis.

  4. Development and Validation of a Novel Gas Analyzer for Simultaneous Measurements of Methane, Carbon Dioxide and Water Vapor in Ambient Air at 20 Hz

    NASA Astrophysics Data System (ADS)

    Gupta, M.; Owano, T.; Fellers, R.; Dong, F.; Baer, D.

    2008-12-01

    Methane has increased significantly with human population levels. Pre-1750 ice core data indicates that pre- industrialization levels were about 700 ppbv, while current levels are over 1750 ppbv. In current budget estimates of atmospheric methane, major contributors include both natural (wetlands) and anthropogenic sources (energy, landfills, ruminants, biomass burning, rice agriculture). The strengths of these sources vary spatially and temporally. Estimates of emissions from wetlands are also uncertain due to the extreme variability of these ecosystems. Because methane lifetime is relatively long (8.4 years), atmospheric variations in concentration are small and accuracy in measurement is important for understanding spatial and temporal variability. Atmospheric concentrations of carbon dioxide and methane rose sharply in 2007. Global CO2 climbed by 0.6 percent, or 19 billion tons, in 2007. Methane increased by 27 million tons after nearly a decade with little or no increase. Atmospheric CO2 levels currently stand at 385 ppmv, or about 38 percent higher than pre- industrial levels and the rise in CO2 concentrations has been accelerating since the 1980s when annual increases were around 1.5 ppm per year. Last year the increase was 2.4 ppm. We report on the development, application and independent performance characterization of a novel gas analyzer based on cavity-enhanced laser absorption spectroscopy. The Analyzer provides simultaneous measurements of methane, carbon dioxide and water vapor in ambient air in the field for applications that require high data rates (eddy correlation flux), wide dynamic range (e.g., chamber flux and other applications with concentrations that are ten times typical ambient levels or higher) and highest accuracy (atmospheric monitoring stations). The Analyzer provides continuous measurements at data rates up to 20 Hz and with replicate precision of 1 ppbv for methane (1 second measurement time), 0.2 ppmv for carbon dioxide (1 second

  5. MULTICHANNEL ANALYZER

    DOEpatents

    Kelley, G.G.

    1959-11-10

    A multichannel pulse analyzer having several window amplifiers, each amplifier serving one group of channels, with a single fast pulse-lengthener and a single novel interrogation circuit serving all channels is described. A pulse followed too closely timewise by another pulse is disregarded by the interrogation circuit to prevent errors due to pulse pileup. The window amplifiers are connected to the pulse lengthener output, rather than the linear amplifier output, so need not have the fast response characteristic formerly required.

  6. Can we Replace Arterial Blood Gas Analysis by Pulse Oximetry in Neonates with Respiratory Distress Syndrome, who are Treated According to INSURE Protocol?

    PubMed Central

    Niknafs, Pedram; Norouzi, Elahe; Bahman Bijari, Bahareh; Baneshi, Mohammad Reza

    2015-01-01

    Neonates with respiratory distress syndrome (RDS), who are treated according to INSURE protocol; require arterial blood gas (ABG) analysis to decide on appropriate management. We conducted this study to investigate the validity of pulse oximetry instead of frequent ABG analysis in the evaluation of these patients. From a total of 193 blood samples obtained from 30 neonates <1500 grams with RDS, 7.2% were found to have one or more of the followings: acidosis, hypercapnia, or hypoxemia. We found that pulse oximetry in the detection of hyperoxemia had a good validity to appropriately manage patients without blood gas analysis. However, the validity of pulse oximetry was not good enough to detect acidosis, hypercapnia, and hypoxemia. PMID:25999627

  7. Metabolic analyzer

    NASA Technical Reports Server (NTRS)

    Lem, J. D.

    1977-01-01

    The metabolic analyzer was designed to support experiment M171. It operates on the so-called open circuit method to measure a subject's metabolic activity in terms of oxygen consumed, carbon dioxide produced, minute volume, respiratory exchange ratio, and tidal volume or vital capacity. The system operates in either of two modes. (1) In Mode I, inhaled respiratory volumes are actually measured by a piston spirometer. (2) In Mode II, inhaled volumes are calculated from the exhaled volume and the measured inhaled and exhaled nitrogen concentrations. This second mode was the prime mode for Skylab. Following is a brief description of the various subsystems and their operation.

  8. Analyzing Orientations

    NASA Astrophysics Data System (ADS)

    Ruggles, Clive L. N.

    Archaeoastronomical field survey typically involves the measurement of structural orientations (i.e., orientations along and between built structures) in relation to the visible landscape and particularly the surrounding horizon. This chapter focuses on the process of analyzing the astronomical potential of oriented structures, whether in the field or as a desktop appraisal, with the aim of establishing the archaeoastronomical "facts". It does not address questions of data selection (see instead Chap. 25, "Best Practice for Evaluating the Astronomical Significance of Archaeological Sites", 10.1007/978-1-4614-6141-8_25) or interpretation (see Chap. 24, "Nature and Analysis of Material Evidence Relevant to Archaeoastronomy", 10.1007/978-1-4614-6141-8_22). The main necessity is to determine the azimuth, horizon altitude, and declination in the direction "indicated" by any structural orientation. Normally, there are a range of possibilities, reflecting the various errors and uncertainties in estimating the intended (or, at least, the constructed) orientation, and in more formal approaches an attempt is made to assign a probability distribution extending over a spread of declinations. These probability distributions can then be cumulated in order to visualize and analyze the combined data from several orientations, so as to identify any consistent astronomical associations that can then be correlated with the declinations of particular astronomical objects or phenomena at any era in the past. The whole process raises various procedural and methodological issues and does not proceed in isolation from the consideration of corroborative data, which is essential in order to develop viable cultural interpretations.

  9. Simultaneous determination of parabens, alkylphenols, phenylphenols, bisphenol A and triclosan in human urine, blood and breast milk by continuous solid-phase extraction and gas chromatography-mass spectrometry.

    PubMed

    Azzouz, Abdelmonaim; Rascón, Andrés J; Ballesteros, Evaristo

    2016-02-01

    A highly sensitive gas chromatography-mass spectrometry (GC-MS) method for the determination of endocrine disrupting chemicals (EDCs) including parabens, alkylphenols, phenylphenols, bisphenol A and triclosan in human breast milk, blood and urine samples is proposed. Blood and milk require a pretreatment to remove proteins and other substances potentially interfering with the continuous solid-phase extraction (SPE) system used; on the other hand, urine samples can be directly introduced into the system after filtering. Analytes are retained on a LiChrolut EN column and derivatized by silylation following elution with acetonitrile. The resulting trimethylsilyl derivatives are determined by GC-MS. The proposed method exhibited good linearity (r(2)>0.995) for all target EDCs over the concentration range 0.7-10,000ng/l in urine, and 3.3-50,000ng/l in blood and milk. Also, it provided low limits of detection (0.2-1.8ng/l in urine, and 1.0-9.0ng/l in blood and milk), good precision (relative standard deviations less than 7%) and recoveries from 86 to 104%. A total of 24 human fluid samples were analyzed and most found to contain some target EDC at concentrations from 0.10 to 14μg/l. PMID:26637951

  10. Carbogen gas-challenge blood oxygen level-dependent magnetic resonance imaging in hepatocellular carcinoma: Initial results

    PubMed Central

    ZHANG, LONG JIANG; ZHANG, ZHUOLI; XU, JIAN; JIN, NING; LUO, SONG; LARSON, ANDREW C.; LU, GUANG MING

    2015-01-01

    The present study aimed to evaluate the feasibility of performing carbogen gas-challenge blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) measurements in patients with hepatocellular carcinoma (HCC). A total of 25 patients with HCC underwent T2* mapping derived from multi-echo gradient-recalled echo imaging prior to and following breathing carbogen (95% O2 and 5% CO2) for 10 min. Follow-up T2* mapping was performed in 5 patients 1 day after transarterial chemoembolization (TACE). T2*, R2* and ∆R2* values (R2*air - R2*carb) of the whole tumor, the solid region of the tumor and the adjacent liver parenchyma were measured and compared in the patients with HCC. The T2* value of the solid region of the tumor following carbogen breathing was higher than the value following room air breathing (P<0.05), and the R2* value of room air breathing was higher than that following carbogen breathing (P<0.05). ∆R2* values of the tumor and the adjacent liver parenchyma prior to and following carbogen breathing were 2.4±7.8, 8.1±14.7 and 2.0±11.0 sec−1, respectively. R2* values were significantly decreased in 2 cases 1 day after TACE (17.8 vs. −3.4 sec−1 and 10.2 vs. 2.4 sec−1). Overall, carbogen gas-challenge BOLD MRI measurements are feasible in clinical settings and may serve as a novel functional biomarker for monitoring the treatment efficacy of embolic therapies for HCC. PMID:26622788

  11. Carbon dioxide and water budget of grazed grassland in Grünschwaige (Munich, Bavaria) measured by EC-method with an open path gas analyzer

    NASA Astrophysics Data System (ADS)

    Vetter, S.; Bernhofer, Ch.; Auerswald, K.

    2009-04-01

    in 2003 and 2006, lowered evapotranspiration and resulted in lower CO2 sinks or even turned the grassland into a source. This study shows the sensitivity of the carbon dioxide and water vapour fluxes quantified by the eddy covariance method to density correction, which can cause substantial changes in the assessment of the influence of environmental factors on fluxes from grassland. Burba, George G.; McDermitt, Dayle K.; Grelle, Achim; Anderson, Daniel J. and Xu, Liukang (2008): Addressing the influence of instrument surface heat exchange on the measurements of CO2 flux from open-path gas analyzers. Global Change Biology, 14, 1854 - 1876

  12. Optical analyzer

    DOEpatents

    Hansen, A.D.

    1987-09-28

    An optical analyzer wherein a sample of particulate matter, and particularly of organic matter, which has been collected on a quartz fiber filter is placed in a combustion tube, and light from a light source is passed through the sample. The temperature of the sample is raised at a controlled rate and in a controlled atmosphere. The magnitude of the transmission of light through the sample is detected as the temperature is raised. A data processor, differentiator and a two pen recorder provide a chart of the optical transmission versus temperature and the rate of change of optical transmission versus temperature signatures (T and D) of the sample. These signatures provide information as to physical and chemical processes and a variety of quantitative and qualitative information about the sample. Additional information is obtained by repeating the run in different atmospheres and/or different rates or heating with other samples of the same particulate material collected on other filters. 7 figs.

  13. Speech analyzer

    NASA Technical Reports Server (NTRS)

    Lokerson, D. C. (Inventor)

    1977-01-01

    A speech signal is analyzed by applying the signal to formant filters which derive first, second and third signals respectively representing the frequency of the speech waveform in the first, second and third formants. A first pulse train having approximately a pulse rate representing the average frequency of the first formant is derived; second and third pulse trains having pulse rates respectively representing zero crossings of the second and third formants are derived. The first formant pulse train is derived by establishing N signal level bands, where N is an integer at least equal to two. Adjacent ones of the signal bands have common boundaries, each of which is a predetermined percentage of the peak level of a complete cycle of the speech waveform.

  14. Residual gas analyzer mass spectrometry for human breath analysis: a new tool for the non-invasive diagnosis of Helicobacter pylori infection.

    PubMed

    Maity, Abhijit; Banik, Gourab D; Ghosh, Chiranjit; Som, Suman; Chaudhuri, Sujit; Daschakraborty, Sunil B; Ghosh, Shibendu; Ghosh, Barnali; Raychaudhuri, Arup K; Pradhan, Manik

    2014-03-01

    A residual gas analyzer (RGA) coupled with a high vacuum chamber is described for the non-invasive diagnosis of the Helicobacter pylori (H. pylori) infection through ¹³C-urea breath analysis. The present RGA-based mass spectrometry (MS) method is capable of measuring high-precision ¹³CO₂ isotope enrichments in exhaled breath samples from individuals harboring the H. pylori infection. The system exhibited 100% diagnostic sensitivity, and 93% specificity alongside positive and negative predictive values of 95% and 100%, respectively, compared with invasive endoscopy-based biopsy tests. A statistically sound diagnostic cut-off value for the presence of H. pylori was determined to be 3.0‰ using a receiver operating characteristic curve analysis. The diagnostic accuracy and validity of the results are also supported by optical off-axis integrated cavity output spectroscopy measurements. The δ¹³(DOB)C‰ values of both methods correlated well (R² = 0.9973 at 30 min). The RGA-based instrumental setup described here is simple, robust, easy-to-use and more portable and cost-effective compared to all other currently available detection methods, thus making it a new point-of-care medical diagnostic tool for the purpose of large-scale screening of the H. pylori infection in real time. The RGA-MS technique should have broad applicability for ¹³C-breath tests in a wide range of biomedical research and clinical diagnostics for many other diseases and metabolic disorders. PMID:24566134

  15. Clinical evaluation of the Colin ABPM 630 at rest and during exercise: an ambulatory blood pressure monitor with gas-powered cuff inflation.

    PubMed

    White, W B; Lund-Johansen, P; McCabe, E J

    1989-06-01

    The Colin ABPM 630 is a silent, gas-powered (CO2) ambulatory blood pressure monitor which uses both ausculatory and/or oscillometric methods to measure blood pressure. We compared simultaneous, same-arm blood pressures obtained with the monitor with those made by two blinded, skilled clinicians using a mercury column and teaching stethoscope. In a second study, the monitor readings were also compared with opposite-arm intra-arterial recordings of blood pressure. The group mean systolic blood pressures obtained by the Colin monitor via the Korotkoff mode were almost identical to the mercury column readings (127.8 +/- 19.4 versus 128.1 +/- 19.3 mmHg, P = NS) and the limit of agreement (2 standard deviations) for the differences in the two methods was +/- 9 mmHg. The diastolic blood pressure obtained by the Colin monitor was significantly lower than the clinician's readings (-6.0 +/- 5.9 mmHg, P less than 0.0001). Similar findings were obtained with the oscillometric mode, however, the mean systolic blood pressure given by the monitor was slightly higher than that given by the mercury column (1.9 +/- 4.5 mmHg, P less than 0.001). In contrast to the mercury column comparisons, the mean diastolic blood pressure obtained with the monitor was nearly the same as the mean intra-arterial diastolic blood pressure for both the Korotkoff (0.1 +/- 5.6 mmHg) and the oscillometric modes (1.2 +/- 6.3 mmHg). During 100-watt bicycle exercise, there was a considerably greater scatter in the individual comparisons of the monitor and intra-arterial blood pressure than that seen in the measurements at rest, but the group means were again similar.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2778314

  16. Blood monitoring of perfluorocarbon compounds (F-tert-butylcyclohexane, perfluoromethyldecalin and perfluorodecalin) by headspace-gas chromatography-tandem mass spectrometry.

    PubMed

    Giuliani, N; Saugy, M; Augsburger, M; Varlet, V

    2015-11-01

    A headspace-gas chromatography-tandem mass spectrometry (HS-GC-MS/MS) method for the trace measurement of perfluorocarbon compounds (PFCs) in blood was developed. Due to oxygen carrying capabilities of PFCs, application to doping and sports misuse is speculated. This study was therefore extended to perform validation methods for F-tert-butylcyclohexane (Oxycyte(®)), perfluoro(methyldecalin) (PFMD) and perfluorodecalin (PFD). The limit of detection of these compounds was established and found to be 1.2 µg/mL blood for F-tert-butylcyclohexane, 4.9 µg/mL blood for PFMD and 9.6 µg/mL blood for PFD. The limit of quantification was assumed to be 12 µg/mL blood (F-tert-butylcyclohexane), 48 µg/mL blood (PFMD) and 96 µg/mL blood (PFD). HS-GC-MS/MS technique allows detection from 1000 to 10,000 times lower than the estimated required dose to ensure a biological effect for the investigated PFCs. Thus, this technique could be used to identify a PFC misuse several hours, maybe days, after the injection or the sporting event. Clinical trials with those compounds are still required to evaluate the validation parameters with the calculated estimations. PMID:26452810

  17. Thickness of the blood-gas barrier in premature and 1-day-old newborn rabbit lungs.

    PubMed

    Fu, Zhenxing; Heldt, Gregory P; West, John B

    2003-07-01

    The pulmonary capillaries of neonatal lungs are potentially vulnerable to stress failure because of the complex changes in the pulmonary circulation that occur at birth. We studied the ultrastructure of the blood-gas barrier (BGB) in premature and 1-day-old rabbit lungs and compared it with the ultrastructure of adult lungs. Normal gestation of rabbits is 30 days. After extensive pilot measurements, three premature (27 days gestation) and three newborn (1 day old) rabbit lungs were perfusion-fixed at arterial, venous, and airway pressures of 25, 0, and 10 cmH2O, respectively, and the measurements were compared with those of three adult lungs. The thickness of the capillary endothelium, alveolar epithelium, and interstitium of the BGB was measured at right angles to the barrier at random points. A striking finding was the large number of measurements of the interstitial thickness in 1-day-old lungs that were very thin (0-0.1 microm). The percentages of occurrence of very thin interstitium in premature, 1-day-old, and adult lungs were 35.3 +/- 9.4, 71.7 +/- 5.2, and 43.0 +/- 2.6, respectively (P < 0.02 for 1 day old vs. premature and adult). Given the previously found relationship between stress failure and interstitial thickness, this large proportion of very thin interstitial layers in the capillaries of 1-day-old lungs is a reasonable explanation for their previously demonstrated vulnerability to stress failure. PMID:12639844

  18. Optical analyzer

    DOEpatents

    Hansen, Anthony D.

    1989-02-07

    An optical analyzer (10) wherein a sample (19) of particulate matter, and particularly of organic matter, which has been collected on a quartz fiber filter (20) is placed in a combustion tube (11), and light from a light source (14) is passed through the sample (19). The temperature of the sample (19) is raised at a controlled rate and in a controlled atmosphere. The magnitude of the transmission of light through the sample (19) is detected (18) as the temperature is raised. A data processor (23), differentiator (28) and a two pen recorder (24) provide a chart of the optical transmission versus temperature and the rate of change of optical transmission versus temperature signatures (T and D) of the sample (19). These signatures provide information as to physical and chemical processes and a variety of quantitative and qualitative information about the sample (19). Additional information is obtained by repeating the run in different atmospheres and/or different rates of heating with other samples of the same particulate material collected on other filters.

  19. Optical analyzer

    DOEpatents

    Hansen, Anthony D.

    1989-01-01

    An optical analyzer (10) wherein a sample (19) of particulate matter, and particularly of organic matter, which has been collected on a quartz fiber filter (20) is placed in a combustion tube (11), and light from a light source (14) is passed through the sample (19). The temperature of the sample (19) is raised at a controlled rate and in a controlled atmosphere. The magnitude of the transmission of light through the sample (19) is detected (18) as the temperature is raised. A data processor (23), differentiator (28) and a two pen recorder (24) provide a chart of the optical transmission versus temperature and the rate of change of optical transmission versus temperature signatures (T and D) of the sample (19). These signatures provide information as to physical and chemical processes and a variety of quantitative and qualitative information about the sample (19). Additional information is obtained by repeating the run in different atmospheres and/or different rates of heating with other samples of the same particulate material collected on other filters.

  20. ABSORPTION ANALYZER

    DOEpatents

    Brooksbank, W.A. Jr.; Leddicotte, G.W.; Strain, J.E.; Hendon, H.H. Jr.

    1961-11-14

    A means was developed for continuously computing and indicating the isotopic assay of a process solution and for automatically controlling the process output of isotope separation equipment to provide a continuous output of the desired isotopic ratio. A counter tube is surrounded with a sample to be analyzed so that the tube is exactly in the center of the sample. A source of fast neutrons is provided and is spaced from the sample. The neutrons from the source are thermalized by causing them to pass through a neutron moderator, and the neutrons are allowed to diffuse radially through the sample to actuate the counter. A reference counter in a known sample of pure solvent is also actuated by the thermal neutrons from the neutron source. The number of neutrons which actuate the detectors is a function of a concentration of the elements in solution and their neutron absorption cross sections. The pulses produced by the detectors responsive to each neu tron passing therethrough are amplified and counted. The respective times required to accumulate a selected number of counts are measured by associated timing devices. The concentration of a particular element in solution may be determined by utilizing the following relation: T2/Ti = BCR, where B is a constant proportional to the absorption cross sections, T2 is the time of count collection for the unknown solution, Ti is the time of count collection for the pure solvent, R is the isotopic ratlo, and C is the molar concentration of the element to be determined. Knowing the slope constant B for any element and when the chemical concentration is known, the isotopic concentration may be readily determined, and conversely when the isotopic ratio is known, the chemical concentrations may be determined. (AEC)

  1. Impact of HPAI H5N1 infection on select blood chemistry and gas ranges in layers, broilers and turkeys using the i-STAT Clinical Analyzer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection of poultry with highly pathogenic avian influenza (HPAI) H5N1 typically results in mortality within six days of inoculation. However, the exact mechanisms that induce death are unknown, even as birds may die in the absence of overt clinical signs of disease. In human and many veterinary ...

  2. Multi-Component Profiling of Trace Volatiles in Blood by Gas Chromatography/Mass Spectrometry with Dynamic Headspace Extraction

    PubMed Central

    Kakuta, Shoji; Yamashita, Toshiyuki; Nishiumi, Shin; Yoshida, Masaru; Fukusaki, Eiichiro; Bamba, Takeshi

    2015-01-01

    A dynamic headspace extraction method (DHS) with high-pressure injection is described. This dynamic extraction method has superior sensitivity to solid phase micro extraction, SPME and is capable of extracting the entire gas phase by purging the headspace of a vial. Optimization of the DHS parameters resulted in a highly sensitive volatile profiling system with the ability to detect various volatile components including alcohols at nanogram levels. The average LOD for a standard volatile mixture was 0.50 ng mL−1, and the average LOD for alcohols was 0.66 ng mL−1. This method was used for the analysis of volatile components from biological samples and compared with acute and chronic inflammation models. The method permitted the identification of volatiles with the same profile pattern as in vitro oxidized lipid-derived volatiles. In addition, the concentration of alcohols and aldehydes from the acute inflammation model samples were significantly higher than that for the chronic inflammation model samples. The different profiles between these samples could also be identified by this method. Finally, it was possible to analyze alcohols and low-molecular-weight volatiles that are difficult to analyze by SPME in high sensitivity and to show volatile profiling based on multi-volatile simultaneous analysis. PMID:26819905

  3. Analysis of Arterial and Venous Blood Gases in Healthy Gyr Falcons ( Falco rusticolus ) Under Anesthesia.

    PubMed

    Raghav, Raj; Middleton, Rachael; BSc, Rinshiya Ahamed; Arjunan, Raji; Caliendo, Valentina

    2015-12-01

    Arterial and venous blood gas analysis is useful in the assessment of tissue oxygenation and ventilation and in diagnosis of metabolic and respiratory derangements. It can be performed with a relatively small volume of blood in avian patients under emergency situations. Arterial and venous blood gas analysis was performed in 30 healthy gyr falcons ( Falco rusticolus ) under anaesthesia to establish temperature-corrected reference intervals for arterial blood gas values and to compare them to temperature-corrected venous blood gas values with a portable point-of-care blood gas analyzer (i-STAT 1, Abbott Laboratories, Abbott Park, IL, USA). Statistically significant differences were observed between the temperature-corrected values of pH, partial pressure of carbon dioxide (Pco2), and partial pressure of oxygen (Po2) and the corresponding nontemperature-corrected values of these parameters in both arterial and venous blood. Values of temperature-corrected pH, temperature-corrected Pco2, bicarbonate concentrations, and base excess of extra cellular fluid did not differ significantly between arterial and venous blood, suggesting that, in anesthetized gyr falcons, venous blood gas analysis can be used in place of arterial blood gas analysis in clinical situations. Values for hematocrit, measured by the point-of-care analyzer, were significantly lower compared with those obtained by the microhematocrit method. PMID:26771318

  4. Calculated changes in pH and pCO2 in arterial blood plasma assuming absence of ion and water exchange between plasma and erythrocytes during their equilibration with alveolar gas.

    PubMed

    Zock, J P; Rispens, P; Zijlstra, W G

    1981-08-01

    As a contribution to solving the problem of pH disequilibrium in arterial blood, the results of two modes of gas exchange in the lung have been calculated using an equilibrium state model of the blood. In both cases the HCO3-/Cl-exchange was assumed to occur after the gas exchange in the pulmonary capillaries. When the gas exchange was assumed to be dependent on intra-erythrocytic carbonic anhydrase, the plasma pH in the arterial blood increased. When plasma erythrocytes were assumed to equilibrate separately with the alveolar gas due to pressure of extra-erythrocytic carbonic anhydrase, plasma pH in the arterial blood decreased. In each case there was a slight increase in pCO2 after the blood had left the pulmonary capillaries. PMID:6793999

  5. The effects of 2 levels of the inspired oxygen fraction on blood gas variables in propofol-anesthetized dogs with high intracranial pressure

    PubMed Central

    Dias, Luis Gustavo Gosuen Gonçalves; Nunes, Newton; Lopes, Patrícia Cristina Ferro; de Almeida, Ricardo Miyasaka; Neto, Gláucia Bueno Pereira; de Souza, Ana Letícia Groszewicz; de Almeida Belmonte, Emílio

    2009-01-01

    The influence of 2 different levels of the inspired oxygen fraction (FiO2) on blood gas variables was evaluated in dogs with high intracranial pressure (ICP) during propofol anesthesia (induction followed by a continuous rate infusion [CRI] of 0.6 mg/kg/min) and intermittent positive pressure ventilation (IPPV). Eight adult mongrel dogs were anesthetized on 2 occasions, 21 d apart, and received oxygen at an FiO2 of 1.0 (G100) or 0.6 (G60) in a randomized crossover fashion. A fiberoptic catheter was implanted on the surface of the right cerebral cortex for assessment of the ICP. An increase in the ICP was induced by temporary ligation of the jugular vein 50 min after induction of anesthesia and immediately after baseline measurement of the ICP. Blood gas measurements were taken 20 min later and then at 15-min intervals for 1 h. Numerical data were submitted to Morrison’s multivariate statistical methods. The ICP, the cerebral perfusion pressure and the mean arterial pressure did not differ significantly between FiO2 levels or measurement times after jugular ligation. The only blood gas values that differed significantly (P < 0.05) were the arterial oxygen partial pressure, which was greater with G100 than with G60 throughout the procedure, and the venous haemoglobin saturation, that was greater with G100 than with G60 at M0. There were no significant differences between FiO2 levels or measurement times in the following blood gas variables: arterial carbon dioxide partial pressure, arterial hemoglobin saturation, base deficit, bicarbonate concentration, pH, venous oxygen partial pressure, venous carbon dioxide partial pressure and the arterial-to-end-tidal carbon dioxide difference. PMID:19436579

  6. Blood volume and red cell mass in children with moderate and severe malaria measured by chromium-53 dilution and gas chromatography/mass spectrometric analysis.

    PubMed

    Macallan, Derek C; Abaye, Daniel A; Dottin, Simone; Onanga, Myriam; Kombila, Maryvonne; Dzeing-Ella, Arnaud; Kremsner, Peter G; Krishna, Sanjeev; Planche, Timothy

    2009-08-30

    Understanding blood volume changes in children with malaria is important for managing fluid status. Traditionally, blood/red cell volume measurements have used radioactive chromium isotopes. We applied an alternative approach, using non-radioactive chromium-53 labelling and mass spectrometry to investigate red cell volume (RCV) in Gabonese children with malaria. Nineteen children with malaria participated (10 severe, 9 moderately severe; ages 15 months to 7 years). Blood labelled with (53)Cr-chromate ex vivo was re-injected, then sampled 30 min later. Pre- and post-injection (53)Cr content were measured by gas chromatography/electron ionisation mass spectrometry of the chromium-trifluoroacetylacetone (TFA) chelate, calibrated against (50)Cr standards. Blood and red cell volumes were calculated from isotopic dilution in 15 of 19 children (in four, insufficient signal mitigated analysis). In this small pilot study, there were no significant differences between moderate and severe cases. Including all subjects, the mean RCV was reduced compared with predicted values (184 vs. 269 mL; p = 0.016) but blood volume, 71 +/- 33 mL/kg (normalised for weight), was close to predicted, approximately 77 mL/kg, commensurate with reduced haematocrit. Blood lactate concentration correlated negatively with RCV/weight (r = -0.56, p = 0.028), consistent with anaemia. In one case, sequential samples over 42 days gave an estimated rate of (53)Cr disappearance of 1.4%/day (equivalent half-life: 70 days). (53)Cr-labelling of red cells may be used to estimate blood and red cell volumes and can be used as an investigative tool in situations such as childhood diseases and resource-constrained settings. Although the red cell mass is depleted in malaria, the blood volume appears relatively well preserved. PMID:19603467

  7. Determination of Neutral Monosaccharides as Per-O-methylated Derivatives Directly from a Drop of Whole Blood by Gas Chromatography-Mass Spectrometry.

    PubMed

    Ciucanu, Ionel; Pilat, Luminiţa; Ciucanu, Cristian Ionuţ; Şişu, Eugen

    2015-11-01

    A new analytical procedure was developed for the simultaneous quantification of neutral monosaccharides from a drop of whole blood using gas chromatography-mass spectrometry analysis (GC-MS) of their per-O-methylated derivatives. The per-O-methylation reaction with methyl iodide and solid sodium hydroxide in methyl sulfoxide was used for the first time for analysis of blood monosaccharides. A blood drop volume of 0.6 μL was used without special purification. The elimination of the undesirable components was carried out during methylation in the presence of a strong base and by liquid extraction of the per-O-methylated monosaccharides. The neutral monosaccharides with an anomeric center gave four per-O-methylated isomers, which were well-separated using a capillary column. Identification was done by electron impact mass spectrometry fragmentation, retention times, and library searching. The limits of detection were determined for standards and varied from 2.0 to 2.3 ng mL(-1). Recoveries for human blood samples varied from 99.22% to 99.65%. The RSD values ranged from 1.92 to 2.37. The method is fast, sensitive, reproducible, and an alternative to current methods for quantitative analysis of blood monosaccharides. PMID:26444378

  8. Determination of cis-permethrin, trans-permethrin and associated metabolites in rat blood and organs by gas chromatography-ion trap mass spectrometry.

    PubMed

    Lestremau, F; Willemin, M-E; Chatellier, C; Desmots, S; Brochot, C

    2014-05-01

    An analytical method was developed to measure cis-permethrin and trans-permethrin in different biological rat matrices and fluids (whole blood, red blood cells, plasma, brain, liver, muscle, testes, kidneys, fat and faeces). The method was also suitable for the simultaneous quantification of their associated metabolites [cis-3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (cis-DCCA), trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (trans-DCCA) and 3-phenoxybenzoic acid (3-PBA)] in blood (whole blood, red blood cells, plasma) and liver. The target analytes were derivatised in samples using a methanolic/hydrochloric acid solution and then extracted with toluene. The analysis was performed by gas chromatography, and detection using ion trap tandem mass spectrometry. The selectivity obtained for complex matrices such as rat organs allowed the use of a purification step to be avoided for most of the matrices investigated. In the case of fat, where permethrin is suspected to accumulate, a dedicated purification step was developed. In fluids, the limits of quantification were at the 50 ng/mL level for the parent compounds and 3-PBA and at 25 ng/mL for cis-DCCA and trans-DCCA. For solid matrices excluding fat, the limits of quantification ranged from 50 ng/g for muscle to 100 ng/g for brain and testes for both cis-permethrin and trans-permethrin. The extraction recoveries ranged primarily between 80 and 120% for the matrix tested. The stability of blood samples was tested through the addition of 1% v/v formic acid. The methods developed were applied in a toxicokinetic study in adult rats. cis-Permethrin and the metabolites were detected in all corresponding matrices, whereas trans-permethrin was detected only in blood, plasma and faeces. PMID:24718437

  9. Phenotype and Age Differences in Blood Gas Characteristics, Electrolytes, Hemoglobin, Plasma Glucose and Cortisol in Female Squirrel Monkeys

    NASA Technical Reports Server (NTRS)

    Brizzee, K. R.; Ordy, J. M.; Dunlap, W. P.; Kendrick, R.; Wengenack, T. M.

    1988-01-01

    Due to its small size, lower cost, tractable nature, successful breeding in captivity and its status near the middle of the primate phylogenetic scale, the squirrel monkey has become an attractive primate model for basic and biomedical research. Although the squirrel monkey now is being used more extensively in many laboratories with diverse interests, only fragmentary reports have been published regarding basic physiological characteristics, or baseline blood reference values of different phenotypes, particularly blood gases, hematology and serum chemical constituents. It is becoming recognized increasingly that these baseline blood reference values are important not only in the care and maintenance of the squirrel monkey, but are critical for assessing normal physiological status, as well as the effects of various experimental treatments. The purpose of this study was to compare differences in blood gases, electrolytes, hematology, blood glucose and cortisol among young and old Bolivian (Roman type) and Colombian (Gothic type) phenotypes of the squirrel monkey.

  10. The effect of adding CO2 to hypoxic inspired gas on cerebral blood flow velocity and breathing during incremental exercise.

    PubMed

    Fan, Jui-Lin; Kayser, Bengt

    2013-01-01

    Hypoxia increases the ventilatory response to exercise, which leads to hyperventilation-induced hypocapnia and subsequent reduction in cerebral blood flow (CBF). We studied the effects of adding CO2 to a hypoxic inspired gas on CBF during heavy exercise in an altitude naïve population. We hypothesized that augmented inspired CO2 and hypoxia would exert synergistic effects on increasing CBF during exercise, which would improve exercise capacity compared to hypocapnic hypoxia. We also examined the responsiveness of CO2 and O2 chemoreception on the regulation ventilation ([Formula: see text]E) during incremental exercise. We measured middle cerebral artery velocity (MCAv; index of CBF), [Formula: see text]E, end-tidal PCO2, respiratory compensation threshold (RC) and ventilatory response to exercise ([Formula: see text]E slope) in ten healthy men during incremental cycling to exhaustion in normoxia and hypoxia (FIO2 = 0.10) with and without augmenting the fraction of inspired CO2 (FICO2). During exercise in normoxia, augmenting FICO2 elevated MCAv throughout exercise and lowered both RC onset and[Formula: see text]E slope below RC (P<0.05). In hypoxia, MCAv and [Formula: see text]E slope below RC during exercise were elevated, while the onset of RC occurred at lower exercise intensity (P<0.05). Augmenting FICO2 in hypoxia increased [Formula: see text]E at RC (P<0.05) but no difference was observed in RC onset, MCAv, or [Formula: see text]E slope below RC (P>0.05). The [Formula: see text]E slope above RC was unchanged with either hypoxia or augmented FICO2 (P>0.05). We found augmenting FICO2 increased CBF during sub-maximal exercise in normoxia, but not in hypoxia, indicating that the 'normal' cerebrovascular response to hypercapnia is blunted during exercise in hypoxia, possibly due to an exhaustion of cerebral vasodilatory reserve. This finding may explain the lack of improvement of exercise capacity in hypoxia with augmented CO2. Our data further indicate that

  11. Capabilities of Direct Sample Introduction - Comprehensive Two-Dimensional Gas Chromatgraphy-Time-of-Flight Mass Spectrometry to Analyze Organic Chemicals of Interest in Fish Oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most analytical methods for persistent organic pollutants (POPs) focus on targeted analytes. Therefore, analysis of multiple classes of POPs typically entails several sample preparations, fractionations, and injections, whereas other chemicals of possible interest are neglected. To analyze a wider...

  12. A selective and sensitive method for quantitation of lysergic acid diethylamide (LSD) in whole blood by gas chromatography-ion trap tandem mass spectrometry.

    PubMed

    Libong, Danielle; Bouchonnet, Stéphane; Ricordel, Ivan

    2003-01-01

    A gas chromatography-ion trap tandem mass spectrometry (GC-ion trap MS-MS) method for detection and quantitation of LSD in whole blood is presented. The sample preparation process, including a solid-phase extraction step with Bond Elut cartridges, was performed with 2 mL of whole blood. Eight microliters of the purified extract was injected with a cold on-column injection method. Positive chemical ionization was performed using acetonitrile as reagent gas; LSD was detected in the MS-MS mode. The chromatograms obtained from blood extracts showed the great selectivity of the method. GC-MS quantitation was performed using lysergic acid methylpropylamide as the internal standard. The response of the MS was linear for concentrations ranging from 0.02 ng/mL (detection threshold) to 10.0 ng/mL. Several parameters such as the choice of the capillary column, the choice of the internal standard and that of the ionization mode (positive CI vs. EI) were rationalized. Decomposition pathways under both ionization modes were studied. Within-day and between-day stability were evaluated. PMID:12587679

  13. Fatty acid profiling of raw human plasma and whole blood using direct thermal desorption combined with gas chromatography-mass spectrometry.

    PubMed

    Akoto, Lawrence; Vreuls, René J J; Irth, Hubertus; Pel, Roel; Stellaard, Frans

    2008-04-01

    Gas chromatography (GC) has in recent times become an important tool for the fatty acid profiling of human blood and plasma. An at-line procedure used in the fatty acid profiling of whole/intact aquatic micro-organisms without any sample preparation was adapted for this work. A direct thermal desorption (DTD) interface was used to profile the fatty acid composition of human plasma and whole human blood of eight volunteers in a procedure omitting the usual lipid extraction steps that precede sample methylation in the traditional (off-line) protocols. Trimethylsulfonium hydroxide (TMSH) was used as reagent for thermally assisted methylation. In a fully automated manner, the liner of the GC injector is used as a sample-and-reaction container with the aid of the DTD interface. The fatty acid methyl ester (FAME) profiles obtained using this novel approach, were very identical to those obtained when the traditional off-line protocol was applied. FAME yields obtained in the at-line DTD method were found to be very similar for saturated fatty acids, but significantly higher for polyunsaturated fatty acids compared to off-line yields. As a result of the contribution of circulating cell membranes in blood, substantial differences were observed when the amount of FAMEs obtained in whole human blood and human plasma samples were compared after their analysis. Thanks to the fully automated operation of this novel procedure, large series of analyses can easily be performed. PMID:17889883

  14. Combining density functional theory (DFT) and collision cross-section (CCS) calculations to analyze the gas-phase behaviour of small molecules and their protonation site isomers.

    PubMed

    Boschmans, Jasper; Jacobs, Sam; Williams, Jonathan P; Palmer, Martin; Richardson, Keith; Giles, Kevin; Lapthorn, Cris; Herrebout, Wouter A; Lemière, Filip; Sobott, Frank

    2016-06-20

    Electrospray ion mobility-mass spectrometry (IM-MS) data show that for some small molecules, two (or even more) ions with identical sum formula and mass, but distinct drift times are observed. In spite of showing their own unique and characteristic fragmentation spectra in MS/MS, no configurational or constitutional isomers are found to be present in solution. Instead the observation and separation of such ions appears to be inherent to their gas-phase behaviour during ion mobility experiments. The origin of multiple drift times is thought to be the result of protonation site isomers ('protomers'). Although some important properties of protomers have been highlighted by other studies, correlating the experimental collision cross-sections (CCSs) with calculated values has proven to be a major difficulty. As a model, this study uses the pharmaceutical compound melphalan and a number of related molecules with alternative (gas-phase) protonation sites. Our study combines density functional theory (DFT) calculations with modified MobCal methods (e.g. nitrogen-based Trajectory Method algorithm) for the calculation of theoretical CCS values. Calculated structures can be linked to experimentally observed signals, and a strong correlation is found between the difference of the calculated dipole moments of the protomer pairs and their experimental CCS separation. PMID:27264846

  15. High-speed Air Temperature Measurements in a Closed-path Cell and Quality of CO2 and H2O Fluxes from a Short-tube Gas Analyzer.

    NASA Astrophysics Data System (ADS)

    Burba, G. G.; Kathilankal, J. C.; Fratini, G.

    2015-12-01

    Gas analyzers traditionally used for eddy covariance method measure gas density. When fluxes are calculated, corrections are applied to account for the changes in gas density due to changing temperature and pressure (Ideal Gas Law) and changing water vapor density (Dalton's Law). The new generation of gas analyzers with fast air temperature and pressure measurements in the sampling cell enables on-the-fly calculation of fast dry mole fraction. This significantly simplifies the flux processing because the WPL density terms are no longer required, and leads to the reduction in uncertainties associated with latent and sensible heat flux inputs into the density terms. Traditional closed-path instruments with long intake tubes often can effectively dampen the fast temperature fluctuations in the tube before reaching the measurement cell, thus reducing or eliminating the need for temperature correction for density-based fluxes. But in instruments with a short-tube design, most - but not all - of the temperature fluctuations are attenuated, so calculating unbiased fluxes using fast dry mole fraction requires high-speed precise temperature measurements of the air stream inside the cell. Fast pressure and water vapor content of the sampled air should also be measured in the cell and carefully aligned in time with gas density and sample temperature measurements.In this study we examine the impact of fast-response air temperature measurements in the cell on the calculations of carbon dioxide and water vapor fluxes at different time scales from three different ecosystems. The fast cell air temperature data is filtered mathematically to obtain slower response cell temperature time series, which is used in the calculation of fluxes. This exercise is intended to simulate the use of thicker slower response thermocouples instead of fast response fine wire thermocouples for estimating cell temperature. The directly measured block temperature is also utilized to illustrate the

  16. Gas exchange and the coagulation system of the blood during the effect on the body of high concentrations of oxygen and carbon dioxide

    NASA Technical Reports Server (NTRS)

    Palosh, L.; Agadzhanyan, N. A.; Davydov, G. A.; Rybakov, B. K.; Sergiyenko, A. S.

    1974-01-01

    Maximum permissible concentrations of oxygen and carbon dioxide in a controlled atmosphere were determined by evaluating their effects on human gas exchange, blood coagulation, and tolerances to acute hypoxia, acceleration, and physical loads. It was found that functional disturbances depend on the concentration of respiratory gases and the length of stay in an altered atmosphere. By changing the atmospheric composition and by bringing the gaseous environment into accordance with the work and rest regimen and energy expenditures, the general reactivity of the body changes favorably.

  17. Formaldehyde vapor produced from hexamethylenetetramine and pesticide: Simultaneous monitoring of formaldehyde and ozone in chamber experiments by flow-based hybrid micro-gas analyzer.

    PubMed

    Yanaga, Akira; Hozumi, Naruto; Ohira, Shin-Ichi; Hasegawa, Asako; Toda, Kei

    2016-02-01

    Simultaneous analysis of HCHO and O3 was performed by the developed flow analysis system to prove that HCHO vapor is produced from solid pesticide in the presence of O3. HCHO is produced in many ways, including as primary emissions from fuel combustion and in secondary production from anthropogenic and biogenic volatile organic compounds by photochemical reactions. In this work, HCHO production from pesticides was investigated for the first time. Commonly pesticide contains surfactant such as hexamethylenetetramine (HMT), which is a heterocyclic compound formed from six molecules of HCHO and four molecules of NH3. HMT can react with gaseous oxidants such as ozone (O3) to produce HCHO. In the present study, a flow analysis system was developed for simultaneous analysis of HCHO and O3, and this system was used to determine if solid pesticides produced HCHO vapor in the presence of O3. HMT or the pesticide jimandaisen, which contains mancozeb as the active ingradient and HMT as a stabilizer was placed at the bottom of a 20-L stainless steel chamber. Air in the chamber was monitored using the developed flow system. Analyte gases were collected into an absorbing solution by a honeycomb-patterned microchannel scrubber that was previously developed for a micro gas analysis system (μGAS). Subsequently, indigotrisulfonate, a blue dye, was added to the absorbing solution to detect O3, which discolored the solution. HCHO was detected after mixing with the Hantzsch reaction reagent. Both gases could be detected at concentrations ranging from parts per billion by volume (ppbv) to 1000 ppbv with good linearity. Both HMT and jimandaisen emitted large amount of HCHO in the presence of O3. PMID:26653496

  18. A gas chromatography-thermal conductivity detection method for helium detection in postmortem blood and tissue specimens.

    PubMed

    Schaff, Jason E; Karas, Roman P; Marinetti, Laureen

    2012-03-01

    In cases of death by inert gas asphyxiation, it can be difficult to obtain toxicological evidence supporting assignment of a cause of death. Because of its low mass and high diffusivity, and its common use as a carrier gas, helium presents a particular challenge in this respect. We describe a rapid and simple gas chromatography-thermal conductivity detection method to qualitatively screen a variety of postmortem biological specimens for the presence of helium. Application of this method is demonstrated with three case examples, encompassing an array of different biological matrices. PMID:22337780

  19. EPA method to-15 VOCs in air collected in SUMMA (trade name) canisters and analyzed by gas chromatography/mass spectrometry. Final report

    SciTech Connect

    McClenny, W.A.; Oliver, K.D.; Adams, J.R.

    1996-04-18

    Method TO-15 is an addition to the EPA Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air and consists of guidance for the sampling and analysis of volatile organic compounds (VOCs) in air. The method has undergone an initial review by the EPA and has been placed on the AMTIC bulletin board maintained by EPA`s Office of Air Quality Planning and Standards (OAQPS) for further comments before final review and formal acceptance as a new method. The method is a companion method to the previously published TO-14 method entitled, `Determination of Volatile Organic Compounds (VOCs) in Ambient Air Using SUMMA(TM) Polished Canister Sampling and Gas Chromatographic (GC) Analysis`. TO-15 differs from TO-14 in the following ways: (1) the water management system consists of the use of a small sample volume or a multisorbent/dry purge technique or both to dry the air sample; (2) the more extensive set of compounds given in Title III of the Clean Air Act Amemdments (CAAA) of 1990 constitutes the target list; (3) GC/MS techniques are recommended as the only means to identify and quantify target compounds; (4) method performance criteria are specified for acceptance of data, thereby allowing the use of alternate but equivalent sampling and analytical instrumentation; and (5) enhanced provisions for quality control are included.

  20. SURFACE CHEMKIN-III: A Fortran package for analyzing heterogeneous chemical kinetics at a solid-surface - gas-phase interface

    SciTech Connect

    Coltrin, M.E.; Kee, R.J.; Rupley, F.M.; Meeks, E.

    1996-05-01

    This document is the user`s manual for the SURFACE CHEMKIN-III package. Together with CHEMKIN-III, this software facilitates the formation, solution, and interpretation of problems involving elementary heterogeneous and gas-phase chemical kinetics in the presence of a solid surface. The package consists of two major software components: an Interpreter and a Surface Subroutine Library. The Interpreter is a program that reads a symbolic description of a user-specified chemical reaction mechanism. One output from the Interpreter is a data file that forms a link to the Surface Subroutine Library, which is a collection of about seventy modular Fortran subroutines that may be called from a user`s application code to return information on chemical production rates and thermodynamic properties. This version of SURFACE CHEMKIN-III includes many modifications to allow treatment of multi-fluid plasma systems, for example modeling the reactions of highly energetic ionic species with a surface. Optional rate expressions allow reaction rates to depend upon ion energy rather than a single thermodynamic temperature. In addition, subroutines treat temperature as an array, allowing an application code to define a different temperature for each species. This version of SURFACE CHEMKIN-III allows use of real (non-integer) stoichiometric coefficients; the reaction order with respect to species concentrations can also be specified independent of the reaction`s stoichiometric coefficients. Several different reaction mechanisms can be specified in the Interpreter input file through the new construct of multiple materials.

  1. Computational study and error analysis of an integrated sampling-probe and gas-analyzer for mixing measurements in supersonic flow

    NASA Astrophysics Data System (ADS)

    Zhu, Wenbo; Ground, Cody; Maddalena, Luca; Viti, Valerio

    2016-09-01

    Concentration probes are employed in supersonic flow mixing measurements. Because the typical design of such probes is essentially based on an inviscid, adiabatic, quasi-1D analysis, the scope of this work is to understand better and quantify the severe impact of viscous effects on the probe’s internal gasdynamics and the associated uncertainties in the measured quantities via a computational fluid dynamics analysis. Specifically, the focus is on the augmented errors due to the aforementioned viscous effects when coupled with various cases of probe-flow misalignment, which is a typical scenario encountered in mixing measurements of binary gas compositions (air and helium in the present work) in vortex-dominated flows. Results show phenomena such as shock induced boundary layer separation and the formation of an oblique shock train. These flow features are found to noticeably affect the accuracy of the composition measurement. The errors associated with the inviscid, adiabatic, quasi-1D analysis of the probes are quantified in this study.

  2. Downhole Fluid Analyzer Development

    SciTech Connect

    Bill Turner

    2006-11-28

    A novel fiber optic downhole fluid analyzer has been developed for operation in production wells. This device will allow real-time determination of the oil, gas and water fractions of fluids from different zones in a multizone or multilateral completion environment. The device uses near infrared spectroscopy and induced fluorescence measurement to unambiguously determine the oil, water and gas concentrations at all but the highest water cuts. The only downhole components of the system are the fiber optic cable and windows. All of the active components--light sources, sensors, detection electronics and software--will be located at the surface, and will be able to operate multiple downhole probes. Laboratory testing has demonstrated that the sensor can accurately determine oil, water and gas fractions with a less than 5 percent standard error. Once installed in an intelligent completion, this sensor will give the operating company timely information about the fluids arising from various zones or multilaterals in a complex completion pattern, allowing informed decisions to be made on controlling production. The research and development tasks are discussed along with a market analysis.

  3. Simultaneous determination of polycyclic musks in blood and urine by solid supported liquid-liquid extraction and gas chromatography-tandem mass spectrometry.

    PubMed

    Liu, Hongtao; Huang, Liping; Chen, Yuxin; Guo, Liman; Li, Limin; Zhou, Haiyun; Luan, Tiangang

    2015-06-15

    A rapid, precise and accurate method for the simultaneous determination of 5 polycyclic musks (PCMs) in biological fluids was developed by solid supported liquid-liquid extraction (SLE) coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS). All parameters influencing SLE-GC-MS performance, including electron energy of electron-impact ionization source, collision energy for tandem mass spectrometer when operated in selected-reaction monitoring (SRM) mode, type and volume of elution reagent, nitrogen evaporation time, pH and salinity of sample have been carefully optimized. Eight milliliter of n-hexane was finally chosen as elution reagent. Blood and urine sample could be loaded into SLE cartridge without adjusting pH and salinity. Deuterated tonalide (AHTN-d3) was chosen as internal standard. The correlation coefficient (r(2)) of the calibration curves of target compounds ranged from 0.9996 to 0.9998. The dynamic range spanned over two orders of magnitude. The limit of detection (LOD) of target compounds in blood and urine ranged from 0.008 to 0.105μgL(-1) and 0.005 to 0.075μgL(-1), respectively. The developed procedure was successfully applied to the analysis of PCMs in human blood and urine obtaining satisfying recoveries on low, medium and high levels. The method was compared with SLE-GC-MS and shown one to two orders of magnitude improvement in sensitivity. PMID:25965876

  4. Blood Disorders

    MedlinePlus

    ... and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells and platelets. Blood disorders affect one or more parts of the blood and prevent ...

  5. Blood sugar test - blood

    MedlinePlus

    ... drink a certain amount of glucose ( oral glucose tolerance test ) How the Test will Feel When the ... a fasting blood glucose, HbA1c test , or glucose tolerance test , depending on your random blood glucose test ...

  6. Improved nondispersive infrared analyzer

    NASA Technical Reports Server (NTRS)

    Dimeff, J.

    1974-01-01

    Light from radiant energy source passes through filter, sample, and reference gas chambers to detector. Chamber with amount of gas to be measured is sealed. Filter may be gelatinous, interference, dispersive, or negative-gas, as required.

  7. Spatial and functional relationships between air conduits and blood capillaries in the pulmonary gas exchange tissue of adult and developing chickens.

    PubMed

    Makanya, Andrew N; El-Darawish, Yosif; Kavoi, Boniface M; Djonov, Valentin

    2011-02-01

    The documented data regarding the three-dimensional structure of the air capillaries (ACs), the ultimate sites of gas exchange in the avian lung is contradictory. Further, the mode of gas exchange, described as cross-current has not been clearly elucidated. We studied the temporal and spatial arrangement of the terminal air conduits of the chicken lung and their relationship with the blood capillaries (BCs) in embryos as well as the definitive architecture in adults. Several visualization techniques that included corrosion casting, light microscopy as well as scanning and transmission electron microscopy were used. Two to six infundibulae extend from each atrium and give rise to numerous ACs that spread centrifugally. Majority of the ACs are tubular structures that give off branches, which anastomose with their neighboring cognates. Some ACs have globular shapes and a few are blind-ending tapering tubes. During inauguration, the luminal aspects of the ACs are characterized by numerous microvillus-like microplicae, which are formed during the complex processes of cell attenuation and canalization of the ACs. The parabronchial exchange BCs, initially inaugurated as disorganized meshworks, are reoriented via pillar formation to lie predominantly orthogonal to the long axes of the ACs. The remodeling of the retiform meshworks by intussusceptive angiogenesis essentially accomplishes a cross-current system at the gas exchange interface in the adults, where BCs form ring-like patterns around the ACs, thus establishing a cross-current system. Our findings clarify the mode of gas exchange in the parabronchial mantle and illuminate the basis for the functional efficiency of the avian lung. PMID:21275004

  8. Digital Microfluidics Sample Analyzer

    NASA Technical Reports Server (NTRS)

    Pollack, Michael G.; Srinivasan, Vijay; Eckhardt, Allen; Paik, Philip Y.; Sudarsan, Arjun; Shenderov, Alex; Hua, Zhishan; Pamula, Vamsee K.

    2010-01-01

    Three innovations address the needs of the medical world with regard to microfluidic manipulation and testing of physiological samples in ways that can benefit point-of-care needs for patients such as premature infants, for which drawing of blood for continuous tests can be life-threatening in their own right, and for expedited results. A chip with sample injection elements, reservoirs (and waste), droplet formation structures, fluidic pathways, mixing areas, and optical detection sites, was fabricated to test the various components of the microfluidic platform, both individually and in integrated fashion. The droplet control system permits a user to control droplet microactuator system functions, such as droplet operations and detector operations. Also, the programming system allows a user to develop software routines for controlling droplet microactuator system functions, such as droplet operations and detector operations. A chip is incorporated into the system with a controller, a detector, input and output devices, and software. A novel filler fluid formulation is used for the transport of droplets with high protein concentrations. Novel assemblies for detection of photons from an on-chip droplet are present, as well as novel systems for conducting various assays, such as immunoassays and PCR (polymerase chain reaction). The lab-on-a-chip (a.k.a., lab-on-a-printed-circuit board) processes physiological samples and comprises a system for automated, multi-analyte measurements using sub-microliter samples of human serum. The invention also relates to a diagnostic chip and system including the chip that performs many of the routine operations of a central labbased chemistry analyzer, integrating, for example, colorimetric assays (e.g., for proteins), chemiluminescence/fluorescence assays (e.g., for enzymes, electrolytes, and gases), and/or conductometric assays (e.g., for hematocrit on plasma and whole blood) on a single chip platform.

  9. THE DETERMINATION OF CORRELATION LINKAGES BETWEEN LEVEL OF REACTIVE OXYGEN SPECIES, CONTENTS OF NEUTROPHILES AND BLOOD GAS COMPOSITION IN EXPERIMENTAL ACUTE LUNG INJURY.

    PubMed

    Marushchak, M; Krynytska, I; Petrenko, N; Klishch, I

    2016-04-01

    Acute lung injury (ALI) remains a major cause of acute respiratory failure and death of patients. Despite the achievements at the current stage in treatment, morbidity and mortality of ALI remain high. However, a deeper understanding of the pathogenetic links of ALI, identifying of the predictors that positively or negatively influence on the course of the syndrome, the correlation between some pathogenetic mechanisms will improve therapeutic strategies for patients with ALI, which makes the actuality of this study. The aim of the research was to detect additional pathogenetic mechanisms of the acute lung injury development in rats based on a comparative analysis of the correlations between the level of reactive oxygen species in blood and bronchoalveolar lavage, contents of neutrophils and blood gas composition. The experiments were performed on 54 white nonlinear mature male rats 200-220g in weight. The animals were divided into 5 groups: the 1st - control group (n=6), the 2nd - animals affected by hydrochloric acid for 2 hours (n=12), the 3rd - animals affected by hydrochloric acid for 6 hours (n=12), the 4th - animals affected by hydrochloric acid for 12 hours (n=12), the 5th - animals affected by hydrochloric acid for 24 hours (n=12). Correlation analysis was performed between all the studied indices. Coefficient of linear correlation (r) and its fidelity (p) was calculated that was accordingly denoted in the tables (correlation matrices). The correlation coefficient was significant at p<0.05. Conducted correlative analysis showed that the level of ROS in neutrophils of blood in rats with modeled ALI had a high negative correlative linkage with pH of arterial blood in 2nd and 3rd experimental groups. Conducted correlative analysis of data in BAL showed that the level of ROS in neutrophils in rats with modeled ALI had a strong positive correlative relationship with the number of white blood cells in 3-rd, 4-th and 5-th experimental groups and positive

  10. Determination of VX-G analogue in red blood cells via gas chromatography-tandem mass spectrometry following an accidental exposure to VX.

    PubMed

    McGuire, Jeffrey M; Taylor, James T; Byers, Christopher E; Jakubowski, Edward M; Thomson, Sandra M

    2008-01-01

    A sensitive method for determining exposure to the chemical warfare agent VX is described in which the biomarker ethyl methylphosphonofluoridate (VX-G) is measured in red blood cells (RBCs) following treatment with fluoride ion using isotope-dilution gas chromatography-tandem mass spectrometry. The analyte was isolated via solid-phase extraction and detected using ammonia chemical ionization in the multiple reaction monitoring mode. A good linear relationship was obtained in the quantitative concentration range of 4 ng/mL to 1000 ng/mL with an absolute detection limit of < 1 pg on column. The method has been applied to the analysis of RBCs from a laboratory worker accidentally exposed to VX vapor. Detection and quantitation of VX-G were possible in samples taken as late as 27 days following exposure. PMID:18269797

  11. High-resolution CT in simple coal workers' pneumoconiosis. Lack of correlation with pulmonary function tests and arterial blood gas values.

    PubMed

    Collins, L C; Willing, S; Bretz, R; Harty, M; Lane, E; Anderson, W H

    1993-10-01

    We examined 21 miners by means of standard chest radiography, high-resolution computerized tomography (HRCT), pulmonary function tests, and resting arterial blood gas levels. Using the ILO/UC classification of pneumoconiosis, 7 miners had category 1/0 or 2/1 simple coal workers' pneumoconiosis (CWP). By HRCT, nodules were identified in 12 miners; 4 of 9 were classified as category 0/0 CWP; 2 of 5, 0/1 CWP; 5 of 6, 1/0 CWP; and 1 of 1, 2/1 CWP by chest radiograph. Focal emphysema was identified by HRCT in 7 miners; 4 of 9 were classified as 0/0 CWP; 2 of 5, 0/1 CWP; and 1 of 6, 1/0 CWP by standard chest radiography. Four miners with definite nodules confirmed by HRCT had focal emphysema, while three without nodules had focal emphysema. Pulmonary function testing was not different between miners with or without CWP by standard chest radiography, nor was it different between miners with or without definite nodules evidenced by HRCT. No difference in resting oxygenation was found between any group of miners. The presence of focal emphysema confirmed by HRCT did not significantly affect pulmonary function tests on resting arterial blood gas values. There was, however, a significantly lower FEV1 and mean forced expiratory flow during the middle half of forced vital capacity with lifetime nonsmoking miners. The presence of CWP on chest radiography was significantly correlated with smoking cigarettes but not the years of mining. The presence of nodules on HRCT approached a significant correlation with cigarette smoking, but focal emphysema did not. For detecting evidence of coal dust accumulation in lung parenchyma and identifying focal emphysema, HRCT was more sensitive than standard chest radiography. However, despite earlier detection of parenchymal abnormalities, abnormal pulmonary function attributable to coal dust could not be identified. PMID:8404184

  12. High-resolution CT in simple coal workers' pneumoconiosis. Lack of correlation with pulmonary function tests and arterial blood gas values

    SciTech Connect

    Collins, L.C.; Willing, S.; Bretz, R.; Harty, M.; Lane, E.; Anderson, W.H. )

    1993-10-01

    We examined 21 miners by means of standard chest radiography, high-resolution computerized tomography (HRCT), pulmonary function tests, and resting arterial blood gas levels. Using the ILO/UC classification of pneumoconiosis, 7 miners had category 1/0 or 2/1 simple coal workers' pneumoconiosis (CWP). By HRCT, nodules were identified in 12 miners; 4 of 9 were classified as category 0/0 CWP; 2 of 5, 0/1 CWP; 5 of 6, 1/0 CWP; and 1 of 1, 2/1 CWP by chest radiograph. Focal emphysema was identified by HRCT in 7 miners; 4 of 9 were classified as 0/0 CWP; 2 of 5, 0/1 CWP; and 1 of 6, 1/0 CWP by standard chest radiography. Four miners with definite nodules confirmed by HRCT had focal emphysema, while three without nodules had focal emphysema. Pulmonary function testing was not different between miners with or without CWP by standard chest radiography, nor was it different between miners with or without definite nodules evidenced by HRCT. No difference in resting oxygenation was found between any group of miners. The presence of focal emphysema confirmed by HRCT did not significantly affect pulmonary function tests on resting arterial blood gas values. There was, however, a significantly lower FEV1 and mean forced expiratory flow during the middle half of forced vital capacity with lifetime nonsmoking miners. The presence of CWP on chest radiography was significantly correlated with smoking cigarettes but not the years of mining. The presence of nodules on HRCT approached a significant correlation with cigarette smoking, but focal emphysema did not. For detecting evidence of coal dust accumulation in lung parenchyma and identifying focal emphysema, HRCT was more sensitive than standard chest radiography. However, despite earlier detection of parenchymal abnormalities, abnormal pulmonary function attributable to coal dust could not be identified.

  13. Study of Stress Induced Failure of the Blood-gas Barrier and the Epithelial-epithelial Cells Connections of the Lung of the Domestic Fowl, Gallus gallus Variant Domesticus after Vascular Perfusion

    PubMed Central

    Maina, John N; Jimoh, Sikiru A

    2013-01-01

    Complete blood-gas barrier breaks (BGBBs) and epithelial-epithelial cells connections breaks (E-ECCBs) were enumerated in the lungs of free range chickens, Gallus gallus variant domesticus after vascular perfusion at different pressures. The E-ECCBs surpassed the BGBBs by a factor of ~2. This showed that the former parts of the gas exchange tissue were structurally weaker or more vulnerable to failure than the latter. The differences in the numbers of BGBBs and E-ECCBs in the different regions of the lung supplied with blood by the 4 main branches of the pulmonary artery (PA) corresponded with the diameters of the blood vessels, the angles at which they bifurcated from the PA, and the positions along the PA where they branched off. Most of the BGBBs and the E-ECCBs occurred in the regions supplied by the accessory- and the caudomedial branches: the former is the narrowest branch and the first blood vessel to separate from the PA while the latter is the most direct extension of the PA and is the widest. The E-ECCBs appeared to separate and fail from tensing of the blood capillary walls, as the perfusion- and intramural pressures increased. Compared to the mammalian lungs on which data are available, i.e., those of the rabbit, the dog, and the horse, the blood-gas barrier of the lung of free range chickens appears to be substantially stronger for its thinness. PMID:25288905

  14. Role of central and peripheral opiate receptors in the effects of fentanyl on analgesia, ventilation and arterial blood-gas chemistry in conscious rats.

    PubMed

    Henderson, Fraser; May, Walter J; Gruber, Ryan B; Discala, Joseph F; Puskovic, Veljko; Young, Alex P; Baby, Santhosh M; Lewis, Stephen J

    2014-01-15

    This study determined the effects of the peripherally restricted μ-opiate receptor (μ-OR) antagonist, naloxone methiodide (NLXmi) on fentanyl (25μg/kg, i.v.)-induced changes in (1) analgesia, (2) arterial blood gas chemistry (ABG) and alveolar-arterial gradient (A-a gradient), and (3) ventilatory parameters, in conscious rats. The fentanyl-induced increase in analgesia was minimally affected by a 1.5mg/kg of NLXmi but was attenuated by a 5.0mg/kg dose. Fentanyl decreased arterial blood pH, pO2 and sO2 and increased pCO2 and A-a gradient. These responses were markedly diminished in NLXmi (1.5mg/kg)-pretreated rats. Fentanyl caused ventilatory depression (e.g., decreases in tidal volume and peak inspiratory flow). Pretreatment with NLXmi (1.5mg/kg, i.v.) antagonized the fentanyl decrease in tidal volume but minimally affected the other responses. These findings suggest that (1) the analgesia and ventilatory depression caused by fentanyl involve peripheral μ-ORs and (2) NLXmi prevents the fentanyl effects on ABG by blocking the negative actions of the opioid on tidal volume and A-a gradient. PMID:24284037

  15. Gas chromatography-tandem mass spectrometry analysis of red blood cells from Göttingen minipig following whole-body vapor exposure to VX.

    PubMed

    Byers, C E; McGuire, J M; Hulet, S W; Burnett, D C; Gaviola, B I; Jakubowski, E M; Thomson, S A

    2008-01-01

    A method to detect fluoride ion generated O-ethyl methylphosphonofluoridate (VX-G) in Göttingen minipig red blood cells (RBC) following whole-body exposure to VX vapor utilizing a gas chromatograph-tandem mass spectrometer (GC-MS-MS) has been developed. Dose-response curves for VX exposure were generated after applying the fluoride ion reactivation assay to the RBC fraction of serially collected whole blood samples that were taken after whole-body exposures that varied in both duration and concentration. GC-MS-MS analysis of minipig RBC samples following 180-min exposures at two different concentrations was a more precise indicator for severity of exposure than the analysis of acetylcholinesterase (AChE) inhibition for the same samples. AChE enzyme activity recovered faster than indicated by the apparent elimination rate of VX-G. GC-MS-MS analyses of RBC samples following VX exposure demonstrate this technique has both adequate sensitivity and specificity to indicate the severity of exposure. PMID:18269794

  16. Role of central and peripheral opiate receptors in the effects of fentanyl on analgesia, ventilation and arterial blood-gas chemistry in conscious rats

    PubMed Central

    Henderson, Fraser; May, Walter J.; Gruber, Ryan B.; Discala, Joseph F.; Puscovic, Veljko; Young, Alex P.; Baby, Santhosh M.; Lewis, Stephen J.

    2015-01-01

    This study determined the effects of the peripherally restricted µ-opiate receptor (µ-OR) antagonist, naloxone methiodide (NLXmi) on fentanyl (25 µg/kg, i.v.)-induced changes in (1) analgesia, (2) arterial blood gas chemistry (ABG) and alveolar-arterial gradient (A-a gradient), and (3) ventilatory parameters, in conscious rats. The fentanyl-induced increase in analgesia was minimally affected by a 1.5 mg/kg of NLXmi but was attenuated by a 5.0 mg/kg dose. Fentanyl decreased arterial blood pH, pO2 and sO2 and increased pCO2 and A-a gradient. These responses were markedly diminished in NLXmi (1.5 mg/kg)-pretreated rats. Fentanyl caused ventilatory depression (e.g., decreases in tidal volume and peak inspiratory flow). Pretreatment with NLXmi (1.5 mg/kg, i.v.) antagonized the fentanyl decrease in tidal volume but minimally affected the other responses. These findings suggest that (1) the analgesia and ventilatory depression caused by fentanyl involve peripheral µ-ORs and (2) NLXmi prevents the fentanyl effects on ABG by blocking the negative actions of the opioid on tidal volume and A-a gradient. PMID:24284037

  17. Respiratory rates and arterial blood-gas tensions in healthy rabbits given buprenorphine, butorphanol, midazolam, or their combinations.

    PubMed

    Schroeder, Carrie A; Smith, Lesley J

    2011-03-01

    The objective of this study was to evaluate the respiratory effects of buprenorphine, butorphanol, midazolam, and their combinations in healthy conscious rabbits. Six adult female New Zealand white rabbits were anesthetized briefly with isoflurane by mask to allow placement of a catheter into the central ear artery. After a 60-min recovery period, a baseline arterial sample was obtained. Animals then were injected intramuscularly with either 0.9% NaCl (1 mL), buprenorphine (0.03 mg/kg), butorphanol (0.3 mg/kg), midazolam (2 mg/kg), buprenorphine + midazolam (0.03 mg/kg, 2 mg/kg), or butorphanol + midazolam (0.3 mg/kg, 2 mg/kg). Arterial blood gases were evaluated at 30, 60, 90, 120, 180, 240, and 360 min after drug administration. All drug treatments caused significant decreases in respiratory rate, compared with saline. Buprenorphine and the combinations of midazolam-butorphanol and midazolam-buprenorphine resulted in statistically significant decreases in pO(2). No significant changes in pCO(2) pressure were recorded for any treatment. Increases in blood pH were associated with administration of butorphanol, midazolam, and the combinations of midazolam-butorphanol and midazolam-buprenorphine. In light of these results, buprenorphine and the combinations of midazolam-buprenorphine and midazolam-butorphanol result in statistically significant hypoxemia in rabbits that breathe room air. The degree of hypoxemia is of questionable clinical importance in these healthy subjects. Hypoxemia resulting from these drug combinations may be amplified in rabbits with underlying pulmonary or systemic disease. PMID:21439214

  18. The level of serum ionised calcium, aspartate aminotransferase, insulin, glucose, betahydroxybutyrate concentrations and blood gas parameters in cows with left displacement of abomasum.

    PubMed

    Sen, I; Ok, M; Coskun, A

    2006-01-01

    The purpose of this study was to determine concentrations of serum glucose, aspartate aminotransferase (AST), insulin, beta-hydroxybutyrate (BOH) and ionised calcium (Ica) in dairy cows with left displaced abomasum (LDA) and to compare these parameters before and after surgical correction of LDA. Eighteen Swiss-Holstein dairy cows with LDA were used in this study. Clinically healthy post parturient cows (n: 10) from a local dairy farm were used as control group. Blood samples were collected from the jugular vein from all the cows. Surgery was performed in cows with LDA. Blood samples from cows with LDA were collected 24 hours after surgery. The abomasum was repositioned followed by an omentopexy. Six of the 18 cows with LDA had clinical ketosis as detected with urine dipstick. The mean concentrations of insulin, BOH, glucose and AST in cows with LDA at admission time were increased compared with the healthy cows. But the mean concentration of ICa at admission time was slightly decreased compared with healthy cows. The mean BOH concentration was decreased 24 hours following surgery compared with values on admission time. However, the mean serum AST levels were increased both at admission time and 24 hours after surgery compared with healthy cows. The levels of blood gas parameters in cows with LDA were not significantly different in comparison with healthy cows, although hyperbasemia in six of 18 cows with LDA was determined. In conclusion, the results of this study indicated that serum insulin, glucose, AST and BOH levels were increased in dairy cows with LDA. Serum BOH and ICa levels were decreased 24 hours after surgery compared with values on admission time. All cows with LDA used in this study had subclinical/clinical ketosis. We could say that ketosis might be a risk factor for the displacement of the abomasum. PMID:17203740

  19. Kundt's Tube: An Acoustic Gas Analyzer

    ERIC Educational Resources Information Center

    Aristov, Natasha; Habekost, Gehsa; Habekost, Achim

    2011-01-01

    A Kundt tube is normally used to measure the speed of sound in gases. Therefore, from known speeds of sound, a Kundt tube can be used to identify gases and their fractions in mixtures. In these experiments, the speed of sound is determined by measuring the frequency of a standing sound wave at a fixed tube length, temperature, and pressure. This…

  20. Vomiting blood

    MedlinePlus

    ... first part of the small intestine, or esophagus Blood clotting disorders Defects in the blood vessels of the ... as a complete blood count (CBC), blood chemistries, blood clotting tests, and liver function tests Esophagogastroduodenoscopy (EGD) (placing ...

  1. Blood pressure

    MedlinePlus Videos and Cool Tools

    Normal blood pressure is important for proper blood flow to the body’s organs and tissues. The force of the blood on the walls of the arteries is called blood pressure. Blood pressure is measured both as the heart ...

  2. Blood transfusions

    MedlinePlus

    ... homologous blood donation. Many communities have a blood bank at which any healthy person can donate blood. ... to arrange with your hospital or local blood bank before your surgery to have directed donor blood. ...

  3. Blood pressure

    MedlinePlus Videos and Cool Tools

    Normal blood pressure is important for proper blood flow to the body’s organs and tissues. The force of the blood on the walls of the arteries is called blood pressure. Blood pressure is measured both ...

  4. Changes in blood gas transport of altitude native soccer players near sea-level and sea-level native soccer players at altitude (ISA3600)

    PubMed Central

    Wachsmuth, Nadine; Kley, Marlen; Spielvogel, Hilde; Aughey, Robert J; Gore, Christopher J; Bourdon, Pitre C; Hammond, Kristal; Sargent, Charli; Roach, Gregory D; Sanchez, Rudy Soria; Claros, Jesus C Jimenez; Schmidt, Walter F; Garvican-Lewis, Laura A

    2013-01-01

    Objectives The optimal strategy for soccer teams playing at altitude is not known, that is, ‘fly-in, fly-out’ versus short-term acclimatisation. Here, we document changes in blood gas and vascular volumes of sea-level (Australian, n=20) and altitude (Bolivian, n=19) native soccer players at 3600 m. Methods Haemoglobin-oxygen saturation (Hb-sO2), arterial oxygen content (CaO2), haemoglobin mass (Hbmass), blood volume (BV) and blood gas concentrations were measured before descent (Bolivians only), together with aerobic fitness (via Yo-YoIR1), near sea-level, after ascent and during 13 days at 3600 m. Results At baseline, haemoglobin concentration [Hb] and Hbmass were higher in Bolivians (mean±SD; 18.2±1.0 g/dL, 12.8±0.8 g/kg) than Australians (15.0±0.9 g/dL, 11.6±0.7 g/kg; both p≤0.001). Near sea-level, [Hb] of Bolivians decreased to 16.6±0.9 g/dL, but normalised upon return to 3600 m; Hbmass was constant regardless of altitude. In Australians, [Hb] increased after 12 days at 3600 m to 17.3±1.0 g/dL; Hbmass increased by 3.0±2.7% (p≤0.01). BV decreased in both teams at altitude by ∼400 mL. Arterial partial pressure for oxygen (PaO2), Hb-sO2 and CaO2 of both teams decreased within 2 h of arrival at 3600 m (p≤0.001) but increased over the following days, with CaO2 overcompensated in Australians (+1.7±1.2 mL/100 mL; p≤0.001). Yo-YoIR1 was lower on the 3rd versus 10th day at altitude and was significantly related to CaO2. Conclusions The marked drop in PaO2 and CaO2 observed after ascent does not support the ‘fly-in, fly-out’ approach for soccer teams to play immediately after arrival at altitude. Although short-term acclimatisation was sufficient for Australians to stabilise their CaO2 (mostly due to loss of plasma volume), 12 days appears insufficient to reach chronic levels of adaption. PMID:24282216

  5. Widespread activation of immunity and pro-inflammatory programs in peripheral blood leukocytes of HIV-infected patients with impaired lung gas exchange.

    PubMed

    Crothers, Kristina; Petrache, Irina; Wongtrakool, Cherry; Lee, Patty J; Schnapp, Lynn M; Gharib, Sina A

    2016-04-01

    HIV infection is associated with impaired lung gas transfer as indicated by a low diffusing capacity (DLCO), but the mechanisms are not well understood. We hypothesized that HIV-associated gas exchange impairment is indicative of system-wide perturbations that could be reflected by alterations in peripheral blood leukocyte (PBL) gene expression. Forty HIV-infected (HIV(+)) and uninfected (HIV(-)) men with preserved versus low DLCO were enrolled. All subjects were current smokers and those with acute illness, lung diseases other than COPD or asthma were excluded. Total RNA was extracted from PBLs and hybridized to whole-genome microarrays. Gene set enrichment analysis (GSEA) was performed between HIV(+) versus HIV(-) subjects with preserved DLCO and those with low DLCO to identify differentially activated pathways. Using pathway-based analyses, we found that in subjects with preserved DLCO, HIV infection is associated with activation of processes involved in immunity, cell cycle, and apoptosis. Applying a similar analysis to subjects with low DLCO, we identified a much broader repertoire of pro-inflammatory and immune-related pathways in HIV(+) patients relative to HIV(-) subjects, with up-regulation of multiple interleukin pathways, interferon signaling, and toll-like receptor signaling. We confirmed elevated circulating levels of IL-6 in HIV(+) patients with low DLCO relative to the other groups. Our findings reveal that PBLs of subjects with HIV infection and low DLCO are distinguished by widespread enrichment of immuno-inflammatory programs. Activation of these pathways may alter the biology of circulating leukocytes and play a role in the pathogenesis of HIV-associated gas exchange impairment. PMID:27117807

  6. Determination of 14 benzodiazepines and hydroxy metabolites, zaleplon and zolpidem as tert-butyldimethylsilyl derivatives compared with other common silylating reagents in whole blood by gas chromatography-mass spectrometry.

    PubMed

    Gunnar, Teemu; Ariniemi, Kari; Lillsunde, Pirjo

    2005-04-25

    The most common commercially available silylating reagents, N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA), N,O-bis-(trimethylsilyl)trifluoroacetamide+1% trimethylchlorosilane (BSTFA+1% TMCS) and N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) were evaluated to achieve optimal derivatization conditions for analyzing various benzodiazepines based on gas chromatography-electron impact ionization-mass spectrometry (GC-EI-MS). Sensitivity, repeatability, retention times and stability of the derivatives, as well as specificity of mass fragmentation, were studied in detail. Also other parameters affecting the derivatization chemistry of benzodiazepines are discussed. tert-Butyldimethylsilyl (TBDMS) derivatives proved to be more stable, reproducible and sensitive than corresponding trimethylsilyl (TMS) derivatives for the GC-EI-MS analysis of benzodiazepines. Based on the TBDMS derivatives, a rapid, reliable, sensitive and quantitative GC-MS method was developed for the determination of 14 benzodiazepines and two hydroxy metabolites, as well as two non-benzodiazepine hypnotic agents, zolpidem and zaleplon, using 50 microl of whole blood. The method was completely validated in terms of accuracy, intra- and interday precision, limit of detection (LOD), limit of quantitation (LOQ), linearity, selectivity and extraction efficiency; these were all within the required limits, except for the accuracy of nitrazepam at a medium concentration level. PMID:15734157

  7. Liquid phase separation of proteins based on electrophoretic effects in an electrospray setup during sample introduction into a gas-phase electrophoretic mobility molecular analyzer (CE–GEMMA/CE–ES–DMA)

    PubMed Central

    Weiss, Victor U.; Kerul, Lukas; Kallinger, Peter; Szymanski, Wladyslaw W.; Marchetti-Deschmann, Martina; Allmaier, Günter

    2014-01-01

    Nanoparticle characterization is gaining importance in food technology, biotechnology, medicine, and pharmaceutical industry. An instrument to determine particle electrophoretic mobility (EM) diameters in the single-digit to double-digit nanometer range receiving increased attention is the gas-phase electrophoretic mobility molecular analyzer (GEMMA) separating electrophoretically single charged analytes in the gas-phase at ambient pressure. A fused-silica capillary is used for analyte transfer to the gas-phase by means of a nano electrospray (ES) unit. The potential of this capillary to separate analytes electrophoretically in the liquid phase due to different mobilities is, at measurement conditions recommended by the manufacturer, eliminated due to elevated pressure applied for sample introduction. Measurements are carried out upon constant feeding of analytes to the system. Under these conditions, aggregate formation is observed for samples including high amounts of non-volatile components or complex samples. This makes the EM determination of individual species sometimes difficult, if not impossible. With the current study we demonstrate that liquid phase electrophoretic separation of proteins (as exemplary analytes) occurs in the capillary (capillary zone electrophoresis, CE) of the nano ES unit of the GEMMA. This finding was consecutively applied for on-line desalting allowing EM diameter determination of analytes despite a high salt concentration within samples. The present study is to our knowledge the first report on the use of the GEMMA to determine EM diameters of analytes solubilized in the ES incompatible electrolyte solutions by the intended use of electrophoresis (in the liquid phase) during sample delivery. Results demonstrate the proof of concept of such an approach and additionally illustrate the high potential of a future on-line coupling of a capillary electrophoresis to a GEMMA instrument. PMID:25109866

  8. [Interpretation and use of routine pulmonary function tests: Spirometry, static lung volumes, lung diffusion, arterial blood gas, methacholine challenge test and 6-minute walk test].

    PubMed

    Bokov, P; Delclaux, C

    2016-02-01

    Resting pulmonary function tests (PFT) include the assessment of ventilatory capacity: spirometry (forced expiratory flows and mobilisable volumes) and static volume assessment, notably using body plethysmography. Spirometry allows the potential definition of obstructive defect, while static volume assessment allows the potential definition of restrictive defect (decrease in total lung capacity) and thoracic hyperinflation (increase in static volumes). It must be kept in mind that this evaluation is incomplete and that an assessment of ventilatory demand is often warranted, especially when facing dyspnoea: evaluation of arterial blood gas (searching for respiratory insufficiency) and measurement of the transfer coefficient of the lung, allowing with the measurement of alveolar volume to calculate the diffusing capacity of the lung for CO (DLCO: assessment of alveolar-capillary wall and capillary blood volume). All these pulmonary function tests have been the subject of an Americano-European Task force (standardisation of lung function testing) published in 2005, and translated in French in 2007. Interpretative strategies for lung function tests have been recommended, which define abnormal lung function tests using the 5th and 95th percentiles of predicted values (lower and upper limits of normal values). Thus, these recommendations need to be implemented in all pulmonary function test units. A methacholine challenge test will only be performed in the presence of an intermediate pre-test probability for asthma (diagnostic uncertainty), which is an infrequent setting. The most convenient exertional test is the 6-minute walk test that allows the assessment of walking performance, the search for arterial desaturation and the quantification of dyspnoea complaint. PMID:26657268

  9. An observational study using blood gas analysis to assess neonatal calf diarrhea and subsequent recovery with a European Commission-compliant oral electrolyte solution.

    PubMed

    Sayers, Ríona G; Kennedy, Aideen; Krump, Lea; Sayers, Gearóid P; Kennedy, Emer

    2016-06-01

    An observational study was conducted on dairy calves (51 healthy, 31 with neonatal diarrhea) during outbreaks of diarrhea on 4 dairy farms. Clinical assessment scores (CAS) were assigned to each healthy and diarrheic calf [from 0 (healthy) to 4 (marked illness)]. Blood gas analysis [pH, base excess (BE), Na(+), K(+), Ca(2+), Cl(-), glucose, total hemoglobin, standard HCO3(-), strong ion difference (SID), and anion gap (AG)] was completed for each calf. Repeated measurements were taken in healthy animals, and pre- and postintervention measurements were taken for diarrheic calves. The mean CAS of diarrheic calves was 1.7, with 51, 30, 17, and 2% of calves scoring 1, 2, 3, and 4, respectively. The mean value for blood pH, BE, AG, and SID was 7.26, -4.93mM, 16.3mM, and 38.59mM, respectively. Calves were administered an oral rehydration and buffering solution (ORBS; Vitalife for Calves, Epsilion Ltd., Cork, Ireland) and reassessed. The mean CAS decreased to 0.38 (65% of calves scored 0 and 35% scored 1) at 6 to 18h posttreatment and to 0.03 (98% of calves scored 0 and 2% scored 1) within 24 to 48h. Significant increases in mean value for pH, BE, HCO3(-), Na(+), and SID, and significant decreases in AG, K(+), Ca(2+), and total hemoglobin were recorded posttreatment. The correlation estimates indicated that pH, HCO3(-), and BE were strongly correlated with CAS, with values exceeding 0.60 in all cases. Administration of an ORBS with a high SID and bicarbonate buffer demonstrated rapid recovery from a diarrheic episode in dairy calves. PMID:27060812

  10. Donating Blood

    MedlinePlus

    ... can give blood every 56 days. Before Donating Blood donation starts before you walk in the door of ... regenerate the red blood cells lost during a blood donation. An iron-fortified diet plus daily iron tablets ...

  11. Blood culture

    MedlinePlus

    Culture - blood ... A blood sample is needed . The site where blood will be drawn is first cleaned with an antiseptic such ... organism from the skin getting into (contaminating) the blood sample and causing a false-positive result (see ...

  12. Blood Thinners

    MedlinePlus

    If you have some kinds of heart or blood vessel disease, or if you have poor blood flow to your brain, your doctor may recommend that you take a blood thinner. Blood thinners reduce the risk of heart ...

  13. Blood sugar test - blood

    MedlinePlus

    ... in the way you normally talk or behave Fainting spells Seizures (for the first time) SCREENING FOR ... drawn are slight, but may include: Excessive bleeding Fainting or feeling lightheaded Hematoma (blood accumulating under the ...

  14. [THE STUDY OF THE EFFECTS OF ANXYOLYTIC, ANTIOXIDANT, IMMUNOCORRECTOR AND HYPERBARIC OXYGENATION ON THE DYNAMICS OF MAIN BLOOD GAS AND ELECTROLYTE INDICES AND BEHAVIORAL RESPONSE IN EXPERIMENTAL STRESS MODEL].

    PubMed

    Govsh, E V; Podsevatkin, V G; Blinov, D S; Kiryukhina, S V; Podsevatkina, S V; Bochkareva, N V

    2016-01-01

    Experiments on the model of immobilization stress in albino mice showed that a combination of mexidol, thymogen, and hyperbaric oxygenation reduced adverse effects of diazepam on behavioral response of animals in the black-and-white chamber and elevated cross maze tests and led to optimization of the blood gas composition as manifested by increased oxygen tension, normalization of the partial pressure of carbon dioxide, and restoration of the acid-base balance and blood bicarbonate level. The proposed combined treatment can be recommended for the treatment of patients with stress-induced pathology. PMID:27455576

  15. Effect of extracorporeal ultraviolet blood irradiation on blood cholesterol level

    NASA Astrophysics Data System (ADS)

    Zalesskaya, G. A.; Laskina, O. V.; Mitkovskaya, N. P.; Kirkovsky, V. V.

    2012-07-01

    We have studied the effect of extracorporeal ultraviolet blood irradiation on cholesterol metabolism in patients with cardiovascular diseases. We have carried out a comprehensive analysis of the spectral characteristics of blood and plasma, gas-exchange and oximetry parameters, and the results of a complete blood count and chemistry panel before and after UV blood irradiation. We have assessed the changes in concentrations of cholesterols (total cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides) in the blood of the patients in response to a five-day course of UV blood irradiation. The changes in the spectral characteristics of blood and plasma, the chemistry panel, the gas composition, and the fractional hemoglobin composition initiated by absorption of UV radiation are used to discuss the molecular mechanisms for the effect of therapeutic doses of UV radiation on blood cholesterols.

  16. Analytical strategy based on the combination of gas chromatography coupled to time-of-flight and hybrid quadrupole time-of-flight mass analyzers for non-target analysis in food packaging.

    PubMed

    Cherta, L; Portolés, T; Pitarch, E; Beltran, J; López, F J; Calatayud, C; Company, B; Hernández, F

    2015-12-01

    The potential of an advanced analytical strategy based on the use of gas chromatography (GC) coupled to high resolution mass spectrometry (HRMS) with two different analyzers and ionization sources has been investigated and applied to the non-target analysis of food packaging contaminants. Initially, the approach based on GC-time-of-flight (TOF) MS with electron ionization (EI) source allowed performing a library search and mass accurate measurements of selected ions. Then, a second analysis was performed using hybrid quadrupole (Q) TOF MS with an atmospheric pressure chemical ionization (APCI) source in order to search for the molecular ion or the protonated molecule and study the fragmentation behavior. This analytical strategy was applied to the analysis of four polypropylene/ethylene vinyl alcohol/polypropylene (PP/EVOH/PP) multilayer trays and one PP/Al foil/PP film, each one subjected to migration assays with the food simulants isooctane and Tenax®, in order to investigate its potential on the determination of migrant substances. PMID:26041196

  17. 40 CFR 91.314 - Analyzer accuracy and specifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... or other approved gas standards. (i) Span the full analyzer range using a top range calibration gas... paragraphs (c)(2) (i) and (ii) of this section, check the concentration of the gas selected in paragraph (c... percent for CO2 span gas) of the gas' original named concentration. (v) Provided the requirements...

  18. Blood typing

    MedlinePlus

    ... typing. The liquid part of your blood without cells (serum) is mixed with blood that is known to be type ... ABO typing: If your blood cells stick together when mixed with: Anti-A serum, you have type A blood Anti-B serum, you have type B blood Both anti-A and ...

  19. In-situ continuous water analyzing module

    DOEpatents

    Thompson, Cyril V.; Wise, Marcus B.

    1998-01-01

    An in-situ continuous liquid analyzing system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectometer and the volatile components are continuously analyzed by the mass spectrometer.

  20. Blood lead levels and chronic blood loss

    SciTech Connect

    Manci, E.A.; Cabaniss, M.L.; Boerth, R.C.; Blackburn, W.R.

    1986-03-01

    Over 90% of lead in blood is bound to the erythrocytes. This high affinity of lead for red cells may mean that chronic blood loss is a significant means for excretion of lead. This study sought correlations between blood lead levels and clinical conditions involving chronic blood loss. During May, June and July, 146 patients with normal hematocrits and red cell indices were identified from the hospital and clinic populations. For each patient, age, race, sex and medical history were noted, and a whole blood sample was analyzed by flameless atomic absorption spectrophotometry. Age-and race-matched pairs showed a significant correlation of chronic blood loss with lead levels. Patients with the longest history of blood loss (menstruating women) had the lowest level (mean 6.13 ..mu..g/dl, range 3.6-10.3 ..mu..g/dl). Post-menopausal women had levels (7.29 ..mu..g/dl, 1.2-14 ..mu..g/dl) comparable to men with peptic ulcer disease, or colon carcinoma (7.31 ..mu..g/dl, 5.3-8.6 ..mu..g/dl). The highest levels were among men who had no history of bleeding problems (12.39 ..mu..g/dl, 2.08-39.35 ..mu..g/dl). Chronic blood loss may be a major factor responsible for sexual differences in blood lead levels. Since tissue deposition of environmental pollutants is implicated in diseases, menstruation may represent a survival advantage for women.

  1. Blood Gas Quality Assurance System

    PubMed Central

    Pickler, Lee

    1979-01-01

    Quality assurance of health care delivery is as important as the Voluntary Effort (VE) program is to the health care industry. These two seemingly converse positions require a delicate balance. One way this balance is met is by more effectively utilizing current equipment through improved systems.

  2. Real-time airborne particle analyzer

    DOEpatents

    Reilly, Peter T.A.

    2012-10-16

    An aerosol particle analyzer includes a laser ablation chamber, a gas-filled conduit, and a mass spectrometer. The laser ablation chamber can be operated at a low pressure, which can be from 0.1 mTorr to 30 mTorr. The ablated ions are transferred into a gas-filled conduit. The gas-filled conduit reduces the electrical charge and the speed of ablated ions as they collide and mix with buffer gases in the gas-filled conduit. Preferably, the gas filled-conduit includes an electromagnetic multipole structure that collimates the nascent ions into a beam, which is guided into the mass spectrometer. Because the gas-filled conduit allows storage of vast quantities of the ions from the ablated particles, the ions from a single ablated particle can be analyzed multiple times and by a variety of techniques to supply statistically meaningful analysis of composition and isotope ratios.

  3. Percutaneous umbilical cord blood sampling - series (image)

    MedlinePlus

    ... or blood disorder, your doctor may recommend percutaneous umbilical cord blood sampling (PUBS), which is performed at ... sample of the fetus' blood directly from the umbilical cord. The sample is then analyzed for genetic ...

  4. Use of prototype automated blood culture system and gas-liquid chromatography for the analysis of continuous ambulatory peritoneal dialysis associated infection.

    PubMed Central

    Catchpole, C R; Macrae, F; Brown, J D; Palmer, M; Healing, D E; Richards, N T; Elliott, T S

    1997-01-01

    AIMS: (1) To compare the recovery of organisms from continuous ambulatory peritoneal dialysis (CAPD) effluent fluid obtained from patients with clinical evidence of peritonitis, with an automated system (AS) and the Septichek blood culture system; (2) to evaluate the times to detection of organisms with the two systems; (3) to identify anaerobes from CAPD samples by extended anaerobic culture and gas-liquid chromatography (GLC). METHODS: 168 CAPD effluent fluid samples were studied, representing 157 episodes of peritonitis in 97 patients. CAPD samples were inoculated into two AS bottles-one anaerobic, one aerobic-and a Septichek bottle; samples were also examined for cell count, Gram stain, and direct culture. Culture bottles were then subcultured onto various media, and any organisms isolated were identified. After routine culture, GLC was performed on culture fluid in the anaerobic AS and Septichek bottles. When volatile fatty acids were detected, the broths were cultured anaerobically on specialised medium for a further five days. RESULTS: 147 organisms were isolated from the 168 samples: 96 (57%) yielded growth of significant organisms by direct culture, as compared to 129 (76.8%) by both AS and Septichek. There was no significant difference in isolation rates between AS and Septichek, but time to detection was more rapid with the AS system (p < 0.002). GLC showed volatile fatty acid in 15 specimens; of these, 14 subsequently grew anaerobic organisms. CONCLUSIONS: AS was comparable to Septichek for numbers of isolations. Speed to detection was faster with the AS, which may be an advantage in management of patients with CAPD peritonitis. GLC showed anaerobes in several cases which would not have been detected without prolonged anaerobic culture; thus anaerobic cultures are recommended for patients who are unresponsive to antimicrobials or who have evidence of bowel perforation. PMID:9155676

  5. BLOOD GAS, LACTATE, AND HEMATOLOGY EFFECTS OF VENIPUNCTURE TIMING AND LOCATION AFTER MIST-NET CAPTURE OF MOURNING DOVES (ZENAIDA MACROURA), BOAT-TAILED GRACKLES (QUISCALUS MAJOR), AND HOUSE SPARROWS (PASSER DOMESTICUS).

    PubMed

    Harms, Craig A; Jinks, Maggie R; Harms, Ronald V

    2016-04-01

    Venous blood gas partial pressures, pH, bicarbonate and lactate concentrations, packed cell volume, white blood cell differential counts, and heterophil/lymphocyte ratios were measured from Mourning Doves (Zenaida macroura), Boat-tailed Grackles (Quiscalus major), and House Sparrows (Passer domesticus). Birds were bled promptly after mist-net capture and banding or following a targeted delay of 45-60 min, in order to assess the impacts of a brief holding period commonly practiced in large-scale bird banding operations. Additionally, effects of venipuncture location (basilic [=ulnar] vein versus jugular vein) were evaluated in male Boat-tailed Grackles sampled promptly after capture and banding. All comparisons were with unpaired samples; no birds were subjected to more than one venipuncture. All three species exhibited moderate improvements in blood gas and acid-base status after the delay, with reductions in lactate concentrations with or without concurrent increases in pH and bicarbonate. Boat-tailed Grackles exhibited an increased proportion of heterophils in the differential white blood cell count following a delay in sampling, suggestive of a stress leukogram. There were no significant differences between basilic and jugular venipuncture results from male Boat-tailed Grackles. Most metabolic, respiratory, and acid-base alterations were minor, but a small number of birds exhibited values (e.g., temperature-corrected pH <7.3, lactate >10 mmol/L) that could be of concern if combined with other adverse conditions. For such birds, a short delay between capture and processing could benefit their blood gas and acid-base status, although loss of time foraging or feeding young and greater activation of the hypophyseal-pituitary-adrenal axis are additional considerations. PMID:26845300

  6. Blood Sugar

    MedlinePlus

    Blood sugar, or glucose, is the main sugar found in your blood. It comes from the food you eat, and is your body's main source of energy. Your blood carries glucose to all of your body's cells to use ...

  7. Blood transfusions

    MedlinePlus

    ... are many reasons you may need a blood transfusion: After knee or hip replacement surgery, or other ... your body cannot make enough blood A blood transfusion is a safe and common procedure during which ...

  8. Blood typing

    MedlinePlus

    ... whether or not there are certain proteins, called antigens, on your red blood cells. Blood is often ... There are many antigens besides the major ones (A, B, and Rh). Many minor ones are not routinely detected during blood typing. If ...

  9. Discrepancy in ABO blood grouping.

    PubMed

    Khan, Mohammad Noman; Khan, Taseer Ahmed; Ahmed, Zulfiqar

    2013-08-01

    Discrepancies in blood typing is one of the major reasons in eliciting a transfusion reaction. These discrepancies can be avoided through detailed analysis for the blood typing. Here, we report a subgroup of blood group type-B in the ABO system. Donor's blood was analyzed by employing commercial antisera for blood grouping. The results of forward (known antisera) and reverse (known antigen) reaction were not complimentary. A detailed analysis using the standard protocols by American Association of Blood Banking revealed the blood type as a variant of blood group-B instead of blood group-O. This is suggestive of the fact that blood group typing should be performed with extreme care and any divergence, if identified, should be properly resolved to avoid transfusion reactions. Moreover, a major study to determine the blood group variants in Pakistani population is needed. PMID:23930880

  10. Organic Combustion in the Presence of Ca-Carbonate and Mg-Perchlorate: A Possible Source for the Low Temperature CO2 Release Seen in Mars Phoenix Thermal and Evolved Gas Analyzer Data

    NASA Technical Reports Server (NTRS)

    Archer, Douglas; Ming, D.; Niles, P.; Sutter, B.; Lauer, H.

    2012-01-01

    Two of the most important discoveries of the Phoenix Lander were the detection of approx.0.6% perchlorate [1] and 3-5% carbonate [2] in landing site soils. The Thermal and Evolved Gas Analyzer (TEGA) instrument on the Phoenix lander could heat samples up to approx.1000 C and monitor evolved gases with a mass spectrometer. TEGA detected a low (approx.350 C) and high (approx.750 C) temperature CO2 release. The high temp release was attributed to the thermal decomposition of Ca-carbonate (calcite). The low temperature CO2 release could be due to desorption of CO2, decomposition of a different carbonate mineral, or the combustion of organic material. A new hypothesis has also been proposed that the low temperature CO2 release could be due to the early breakdown of calcite in the presence of the decomposition products of certain perchlorate salts [3]. We have investigated whether or not this new hypothesis is also compatible with organic combustion. Magnesium perchlorate is stable as Mg(ClO4)2-6H2O on the martian surface [4]. During thermal decomposition, this perchlorate salt releases H2O, Cl2, and O2 gases. The Cl2 can react with water to form HCl which then reacts with calcite, releasing CO2 below the standard thermal decomposition temperature of calcite. However, when using concentrations of perchlorate and calcite similar to what was detected by Phoenix, the ratio of high:low temperature CO2 evolved is much larger in the lab, indicating that although this process might contribute to the low temp CO2 release, it cannot account for all of it. While H2O and Cl2 cause calcite decomposition, the O2 evolved during perchlorate decomposition can lead to the combustion of any reduced carbon present in the sample [5]. We investigate the possible contribution of organic molecules to the low temperature CO2 release seen on Mars.

  11. Analyzing Peace Pedagogies

    ERIC Educational Resources Information Center

    Haavelsrud, Magnus; Stenberg, Oddbjorn

    2012-01-01

    Eleven articles on peace education published in the first volume of the Journal of Peace Education are analyzed. This selection comprises peace education programs that have been planned or carried out in different contexts. In analyzing peace pedagogies as proposed in the 11 contributions, we have chosen network analysis as our method--enabling…

  12. Analyzing Costs of Services.

    ERIC Educational Resources Information Center

    Cox, James O.; Black, Talbot

    A simplified method to gather and analyze cost data is presented for administrators of Handicapped Children's Early Education Programs, and specifically for members of the Technical Assistance Development System, North Carolina. After identifying benefits and liabilities associated with analyzing program costs, attention is focused on the internal…

  13. Blood Clots

    MedlinePlus

    ... En Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Blood Clots Blood clots are semi-solid masses of blood that can be stationary (thrombosis) and block blood flow or break loose ( ...

  14. Software Design Analyzer System

    NASA Technical Reports Server (NTRS)

    Tausworthe, R. C.

    1985-01-01

    CRISP80 software design analyzer system a set of programs that supports top-down, hierarchic, modular structured design, and programing methodologies. CRISP80 allows for expression of design as picture of program.

  15. Automatic amino acid analyzer

    NASA Technical Reports Server (NTRS)

    Berdahl, B. J.; Carle, G. C.; Oyama, V. I.

    1971-01-01

    Analyzer operates unattended or up to 15 hours. It has an automatic sample injection system and can be programmed. All fluid-flow valve switching is accomplished pneumatically from miniature three-way solenoid pilot valves.

  16. Generating and Analyzing Data.

    ERIC Educational Resources Information Center

    Stevens, Jill

    1993-01-01

    Presents activities in which students develop and analyze scatterplots on graphing calculators to model corn growth, decay, a box of maximum volume, and weather prediction. Provides reproducible worksheets. (MDH)

  17. Soil Rock Analyzer

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A redesigned version of a soil/rock analyzer developed by Martin Marietta under a Langley Research Center contract is being marketed by Aurora Tech, Inc. Known as the Aurora ATX-100, it has self-contained power, an oscilloscope, a liquid crystal readout, and a multichannel spectrum analyzer. It measures energy emissions to determine what elements in what percentages a sample contains. It is lightweight and may be used for mineral exploration, pollution monitoring, etc.

  18. Stability of blood gases in ice and at room temperature.

    PubMed

    Liss, H P; Payne, C P

    1993-04-01

    Arterial blood samples from 75 patients were analyzed for PO2, PCO2, and pH at 0, 15, and 30 min. After the baseline analysis, 60 samples were kept in ice while 59 samples were left at room temperature. There was a statistically significant increase in the PO2 at 15 min and again at 30 min in both groups. There was a statistically significant decrease in the PCO2 at 15 min in both groups. There were no further changes in the PCO2 at 30 min in either group. There was a statistically significant decrease in the pH at 15 min in both groups. There was a further statistically significant decrease in the pH at 30 min in the group of blood samples left at room temperature but not in those in ice. There is no reason to keep arterial blood in ice if blood gas analysis is done within 30 min. PMID:8131450

  19. Motor vehicle fuel analyzer

    DOEpatents

    Hoffheins, Barbara S.; Lauf, Robert J.

    1997-01-01

    A gas detecting system for classifying the type of liquid fuel in a container or tank. The system includes a plurality of semiconductor gas sensors, each of which differs from the other in its response to various organic vapors. The system includes a means of processing the responses of the plurality of sensors such that the responses to any particular organic substance or mixture is sufficiently distinctive to constitute a recognizable "signature". The signature of known substances are collected and divided into two classes based on some other known characteristic of the substances. A pattern recognition system classifies the signature of an unknown substance with reference to the two user-defined classes, thereby classifying the unknown substance with regard to the characteristic of interest, such as its suitability for a particular use.

  20. Motor vehicle fuel analyzer

    DOEpatents

    Hoffheins, B.S.; Lauf, R.J.

    1997-08-05

    A gas detecting system is described for classifying the type of liquid fuel in a container or tank. The system includes a plurality of semiconductor gas sensors, each of which differs from the other in its response to various organic vapors. The system includes a means of processing the responses of the plurality of sensors such that the responses to any particular organic substance or mixture is sufficiently distinctive to constitute a recognizable ``signature``. The signature of known substances are collected and divided into two classes based on some other known characteristic of the substances. A pattern recognition system classifies the signature of an unknown substance with reference to the two user-defined classes, thereby classifying the unknown substance with regard to the characteristic of interest, such as its suitability for a particular use. 14 figs.