Science.gov

Sample records for densitometers

  1. Impaction densitometer

    DOEpatents

    Parrington, Josef R.

    2016-06-28

    Disclosed is an impaction densitometer having a chamber configured to receive a particle; a beam generator configured to emit a beam; a detector configured to receive the beam and convert a change in intensity of the received beam into an electrical signal corresponding to a particle volume; an impact sensor positioned a known distance from the beam and configured to measure a particle momentum as a function of an impact energy transferred from the particle to the impact sensor; a velocity calculator configured to calculate a particle velocity based on a time it takes the particle to pass through the beam and strike the impact sensor; a mass calculator configured to calculate a particle mass as a function of the particle momentum and velocity; and a density calculator configured to calculate a particle density as a function of the particle mass and volume.

  2. MAGNETIC DENSITOMETER

    DOEpatents

    McCann, J.A.; Jones, R.H.

    1961-08-15

    A magnetic densitometer for locating defects and metallic inclusions in materials is described. The apparatus consists of two primary coils connected in series opposition and adapted te be placed in inductive relation to the material under test, a source of constant frequency alternating current coupled across the primary coil combination, a pick-up coil disposed in symmetrical inductive relationship with said primary coils, a phase-shifter coupled to the output of the energizing source. The output of the phase-shifter is coupled in series with the pick-up coil. An amplifier is provided selective to the third harmonic of the energizing source frequency. The series combination of the pick-up coil and the phase-shifter output are connected across the input of the amplifier, and an amplitude comparitor is coupled to the output of the amplifier and the energizing source for comparing the instantaneous amplitude of the amplifier output and the instantaneous output of the energizing source and producing an output proportional to the difference in amplitude. A recorder is coupled to the output of the amplitude comparison means to give an indication of the amplitude difference, thereby providing a permanent presentation of the character of the changes in characteristics exhibited by the material under test. (AEC)

  3. An optical heterodyne densitometer

    NASA Technical Reports Server (NTRS)

    Migdall, A. L.; Zheng, Ying Cong; Hardis, J.; Snyder, J. J.

    1988-01-01

    Researchers are developing an optical heterodyne densitometer with the potential to measure optical density over an unprecedented dynamic range with high accuracy and sensitivity. This device uses a Mach-Zender interferometer configuration with heterodyne detection to make direct comparisons between optical and RF attenuators. Researchers expect to attain measurements of filter transmittance down to 10 to the minus 12th power with better than 1 percent uncertainty. In addition, they intend to extend the technique to the problem of measuring low levels of light scattering from reflective and transmissive optics.

  4. MIST facility densitometer comparisons

    SciTech Connect

    Childerson, M.T.

    1987-01-01

    Photon attenuation techniques were used in the Multi-Loop Integral Systems Test (MIST) facility to make void fraction and fluid density measurements. The MIST facility was a scaled physical model of a Babcock and Wilcox lowered loop, nuclear steam supply system. The facility was tested at typical pressurized water reactor fluid conditions. The MIST facility was designed for observing integral system response during a small-break loss-of-coolant accident. The data from the MIST tests are used for improving confidence in safety codes. Dual-beam gamma densitometers provided an indication of the void fraction or mixture density of the fluid at the hot- and cold-leg nozzles.

  5. Capacitance densitometer for flow regime identification

    DOEpatents

    Shipp, Jr., Roy L.

    1978-01-01

    This invention relates to a capacitance densitometer for determining the flow regime of a two-phase flow system. A two-element capacitance densitometer is used in conjunction with a conventional single-beam gamma densitometer to unambiguously identify the prevailing flow regime and the average density of a flowing fluid.

  6. 21 CFR 892.1170 - Bone densitometer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bone densitometer. 892.1170 Section 892.1170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1170 Bone densitometer. (a) Identification. A...

  7. 21 CFR 892.1170 - Bone densitometer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Bone densitometer. 892.1170 Section 892.1170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1170 Bone densitometer. (a) Identification. A...

  8. 21 CFR 892.1170 - Bone densitometer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Bone densitometer. 892.1170 Section 892.1170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1170 Bone densitometer. (a) Identification. A...

  9. 21 CFR 892.1170 - Bone densitometer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Bone densitometer. 892.1170 Section 892.1170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1170 Bone densitometer. (a) Identification. A...

  10. 21 CFR 870.1450 - Densitometer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Densitometer. 870.1450 Section 870.1450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... densitometer is a device used to measure the transmission of light through an indicator in a sample of...

  11. 21 CFR 870.1450 - Densitometer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Densitometer. 870.1450 Section 870.1450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... densitometer is a device used to measure the transmission of light through an indicator in a sample of...

  12. Ultrasonic fluid densitometry and densitometer

    DOEpatents

    Greenwood, M.S.; Lail, J.C.

    1998-01-13

    The present invention is an ultrasonic fluid densitometer that uses a material wedge having an acoustic impedance that is near the acoustic impedance of the fluid, specifically less than a factor of 11 greater than the acoustic impedance of the fluid. The invention also includes a wedge having at least two transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

  13. Ultrasonic fluid densitometry and densitometer

    DOEpatents

    Greenwood, Margaret S.; Lail, Jason C.

    1998-01-01

    The present invention is an ultrasonic fluid densitometer that uses a material wedge having an acoustic impedance that is near the acoustic impedance of the fluid, specifically less than a factor of 11 greater than the acoustic impedance of the fluid. The invention also includes a wedge having at least two transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface.

  14. K-edge densitometer (KED)

    SciTech Connect

    Sprinkle, J.K.; Hansen, W.J.

    1993-02-11

    In 1979, a K-edge densitometer (KED) was installed by the Safeguards Assay group from Los Alamos National Laboratory in the PNC reprocessing plant at Tokai-mura, Japan. It uses an active nondestructive assay technique, KED, to measure the plutonium concentration of the product solution. The measurement uncertainty of an assay depends on the count time chosen, but can be 0.5% or better. The computer hardware and software were upgraded in 1992. This manual describes the operation of the instrument, with an emphasis on the user interface to the software.

  15. Compact K-edge densitometer

    SciTech Connect

    Cowder, L.R.; Klosterbuer, S.F.; Augustson, R.H.; Esmailpour, A.; Hawkins, R.; Kuhn, E.

    1984-05-01

    Los Alamos National Laboratory has designed, built, and is currently testing a compact K-edge densitometer for use by International Atomic Energy Agency (IAEA) inspectors. The unit, which can easily be moved from one location to another within a facility, is positioned outside a glovebox with the body of the instrument inserted into the glove. A fixture inside the glovebox fits around the body and positions a sample holder. A hand-held high-purity germanium detector powered by a battery pack and a Davidson portable multichannel analyzer (MCA) is used to measure the transmission through plutonium nitrate solutions at E/sub Y/ = 121.1 and 122.2 keV. The Davidson MCA is programmed to lead the user through the measurement procedure and perform all the data analyses. The instrument is currently installed at the Safeguards Analytical Laboratory, where IAEA personnel are evaluating its accuracy, ease of operation, and safety. 5 references, 5 figures, 5 tables.

  16. 21 CFR 892.1170 - Bone densitometer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... densitometer is a device intended for medical purposes to measure bone density and mineral content by x-ray or gamma ray transmission measurements through the bone and adjacent tissues. This generic type of...

  17. Fast response densitometer for measuring liquid density

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Densitometer was developed which produces linear voltage proportional to changes in density of flowing liquid hydrogen. Unit has fast response time and good system stability, statistical variation, and thermal equilibrium. System accuracy is 2 percent of total density span. Basic design may be altered to include measurement of other flowing materials.

  18. Pitch-catch only ultrasonic fluid densitometer

    DOEpatents

    Greenwood, Margaret S.; Harris, Robert V.

    1999-01-01

    The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface.

  19. Pitch-catch only ultrasonic fluid densitometer

    DOEpatents

    Greenwood, M.S.; Harris, R.V.

    1999-03-23

    The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

  20. Ultrasonic fluid densitometer for process control

    DOEpatents

    Greenwood, Margaret S.

    2000-01-01

    The present invention is an ultrasonic fluid densitometer that uses at least one pair of transducers for transmitting and receiving ultrasonic signals internally reflected within a material wedge. A temperature sensor is provided to monitor the temperature of the wedge material. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface and comparing a transducer voltage and wedge material temperature to a tabulation as a function of density.

  1. Doing it right the first time: Maintaining densitometer calibration

    SciTech Connect

    Burgwardt, L.C.

    1995-09-01

    A densitometer is a key tool for controlling the exposure and development process during radiographic film-based nondestructive testing (NDT) procedures. Yet it may be one of the most overlooked sources of problems affecting the quality of radiographic tests. Radiography labs that provide NDT pay a great deal of attention to their radiation sources, processing procedures, and skilled readings of sample defects in final images. Whether the exposure is created by light or a radiographic source, all photographic processes produce an image on film which consists of a range of densities. Reading the densities of a radiograph detects cracks or subtle fractures to determine if a flaw exists in an aircraft structure, a pipe weld, or any other hidden surface. The visibility of the defect is dependent upon proper exposure and processing of the film. A densitometer helps control those variables. And good densitometer habits, including regular calibration and testing of the densitometer, are an investment in good results.

  2. Quantitative autoradiography of dot blots using a microwell densitometer

    SciTech Connect

    Ross, P.M.; Woodley, K.; Baird, M. )

    1989-07-01

    We have established conditions for the quantitation of DNA hybridization by reading dot blot autoradiographs with a microwell plate densitometer. This method is more convenient, as accurate, and more sensitive than counting the spots in a liquid scintillation counter.

  3. Utility of a scanning densitometer in analyzing remotely sensed imagery

    NASA Technical Reports Server (NTRS)

    Dooley, J. T.

    1976-01-01

    The utility of a scanning densitometer for analyzing imagery in the NASA Lewis Research Center's regional remote sensing program was evaluated. Uses studied include: (1) quick-look screening of imagery by means of density slicing, magnification, color coding, and edge enhancement; (2) preliminary category classification of both low- and high-resolution data bases; and (3) quantitative measurement of the extent of features within selected areas. The densitometer was capable of providing fast, convenient, and relatively inexpensive preliminary analysis of aerial and satellite photography and scanner imagery involving land cover, water quality, strip mining, and energy conservation.

  4. Phosphorimager and PD densitometer imaging system network. Technical report

    SciTech Connect

    1995-05-01

    This document discusses the research projects undertaken as a result of the availability of the PhosphorImager and PD Densitometer Imaging System Network, at the University of Georgia`s Complex Carbohydrate Research Center. The benefit gained from the equipment is described for each project.

  5. 21 CFR 862.2400 - Densitometer/scanner (integrating, reflectance, TLC, or radiochromatogram) for clinical use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Densitometer/scanner (integrating, reflectance, TLC, or radiochromatogram) for clinical use. 862.2400 Section 862.2400 Food and Drugs FOOD AND DRUG... CLINICAL TOXICOLOGY DEVICES Clinical Laboratory Instruments § 862.2400 Densitometer/scanner...

  6. Compact L-edge densitometer for uranium concentration assay

    SciTech Connect

    Brooks, M.L.; Russo, P.A.; Sprinkle, J.K. Jr.

    1985-02-01

    A new L-edge densitometer has been designed around a compact, commercial x-ray generator weighing less than 5 kg. The dc generator x-ray spectrum was tailored to produce a continuum of x-ray energies from 14 to 20 keV. The x rays were transmitted through uranium reference solutions, and the measured transmissions near the uranium L/sub III/-absorption edge were used to compute the uranium concentration assay result. The range of uranium concentrations in the reference solutions included 5 to 50 g/l. In this concentration range, the assay uncertainty for short count times and the flatness of the specific assay response were better than 0.5%. Thus, the precision and accuracy of this compact densitometer are equal to those demonstrated previously for the L-edge technique. The compact dimensions and optimized transmission geometry increase the practicality, versatility, and range of the L-edge applications. 12 references, 12 figures, 4 tables.

  7. [An improved software design of ultrasound bone densitometer].

    PubMed

    Yu, Zhengtao; Yang, Lian; Xu, Shijie; Deng, Jiangjun; Dong, Qingqing; He, Aijun

    2014-10-01

    In order to meet the requirements of ultrasound bone density measurement, we proposed a software solution to improve the accuracy and speed of measurement of bone mineral density of the ultrasound bone densitometer. We used a high-speed USB interface chip FT232H, along with a high-speed AD converter chip to calculate speed of sound (SOS), broadband ultrasound attenuation (BUA ) and other bone density parameters in the PC software. This solution improved the accuracy of the measurement data, reduced the measurement time and increased the quality of the displayed image. It is well concluded that the new software can greatly improve the accuracy and transmission speed of bone density measurement data through a high-speed USB interface and a software data processing technology. PMID:25764722

  8. Operational test report for the AY-102 Enraf densitometer control and acquisition system

    SciTech Connect

    Huber, J.H.

    1998-07-23

    On June 2 through June 10, 1998, the AY-102 Tank Densitometer Control and Acquisition System was operationally tested per OTP-320-01 O Revision A-O. The test was performed at the Department of Energy`s Hanford Site, 200 East Area, 241-AY Tank Farm. The test validated the functionality of the Enraf 854 ATG Densitometer Gauge and Enraf Control Panel software for use by project W-320, Waste Retrieval Sluicing System (WRSS). The purpose of the test procedure was two fold: (1) to verify the functionality of the Enraf 854 ATG as a Densitometer and (2) to verify the functionality of the Enraf Control Panel Software density acquisition routines. The densitometer was previously acceptance tested per HNF-SD-WM-ATP-077. The software was previously acceptance tested per HNF-1991.

  9. Radiation safety analysis of the ISS bone densitometer

    NASA Astrophysics Data System (ADS)

    Todd, Paul; Vellinger, John C.; Barton, Kenneth; Faget, Paul

    A Bone Densitometer (BD) has been developed for installation on the International Space Station (ISS) with delivery by the Space-X Dragon spacecraft planned for mid 2014. After initial tests on orbit the BD will be used in longitudinal measurements of bone mineral density in experimental mice as a means of evaluating countermeasures to bone loss. The BD determines bone mineral density (and other radiographic parameters) by dual energy x-ray absorptiometry (DEXA). In a single mouse DEXA “scan” its 80 kV x-ray tube is operated for 15 seconds at 35 kV and 3 seconds at 80 kV in four repetitions, giving the subject a total dose of 2.5 mSv. The BD is a modification of a commercial mouse DEXA product known as PIXImus(TM). Before qualifying the BD for utilization on ISS it was necessary to evaluate its radiation safety features and any level of risk to ISS crew members. The BD design reorients the PIXImus so that it fits in an EXPRESS locker on ISS with the x-ray beam directed into the crew aisle. ISS regulation SSP 51700 considers the production of ionizing radiation to be a catastrophic-level hazard. Accidental exposure is prevented by three independent levels of on-off control as required for a catastrophic hazard. The ALARA (As Low as Reasonably Achievable) principle was applied to the BD hazard just as would be done on the ground, so deliberate exposure is limited by lead shielding according to ALARA. Hot spots around the BD were identified by environmental dosimetry using a Ludlum 9DP pressurized ionization chamber survey meter. Various thicknesses of lead were applied to the BD housing in areas where highest dose-per-scan readings were made. It was concluded that 0.4 mm of lead shielding at strategic locations, adding only a few kg of mass to the payload, would accomplish ALARA. With shielding in place the BD now exposes a crew member floating 40 cm away to less than 0.08 microSv per mouse scan. There is an upper limit of 20 scans per day, or 1.6 microSv per day

  10. Gamma densitometer for measuring Pu density in fuel tubes

    SciTech Connect

    Winn, W.G.

    1982-01-01

    A fuel-gamma-densitometer (FGD) has been developed to examine nondestructively the uniformity of plutonium in aluminum-clad fuel tubes at the Savannah River Plant (SRP). The monitoring technique is ..gamma..-ray spectroscopy with a lead-collimated Ge(Li) detector. Plutonium density is correlated with the measured intensity of the 208 keV ..gamma..-ray from /sup 237/U (7d) of the /sup 241/Pu (15y) decay chain. The FGD measures the plutonium density within 0.125- or 0.25-inch-diameter areas of the 0.133- to 0.183-inch-thick tube walls. Each measurement yields a density ratio that relates the plutonium density of the measured area to the plutonium density in normal regions of the tube. The technique was used to appraise a series of fuel tubes to be irradated in an SRP reactor. High-density plutonium areas were initially identified by x-ray methods and then examined quantitatively with the FGD. The FGD reliably tested fuel tubes and yielded density ratios over a range of 0.0 to 2.5. FGD measurements examined (1) nonuniform plutonium densities or hot spots, (2) uniform high-density patches, and (3) plutonium density distribution in thin cladding regions. Measurements for tubes with known plutonium density agreed with predictions to within 2%. Attenuation measurements of the 208-keV ..gamma..-ray passage through the tube walls agreed to within 2 to 3% of calculated predictions. Collimator leakage measurements agreed with model calculations that predicted less than a 1.5% effect on plutonium density ratios. Finally, FGD measurements correlated well with x-ray transmission and fluoroscopic measurements. The data analysis for density ratios involved a small correction of about 10% for ..gamma..-shielding within the fuel tube. For hot spot examinations, limited information for this correction dictated a density ratio uncertainty of 3 to 5%.

  11. The long-term performance of DXA bone densitometers.

    PubMed

    Wells, J; Ryan, P J

    2000-07-01

    Long-term performance of a bone mass measuring device is an important criterion when considering the purchase of such equipment and has been regarded as an important feature of dual X-ray absorptiometry (DXA). The performance of a 6-year-old bone densitometer, the Lunar DPX alpha, which has undertaken 1500 scans annually over this period, was assessed. The short-term coefficient of variation calculated from 15 measurements with repositioning on a single day, using the Lunar aluminium phantom, was 0.242%. Long-term precision, also calculated by the coefficient of variation, was 0.548%. The manufacturer's quality control (QC) procedure was performed daily and allowed the machine to be used except on 15 occasions when bone density measurements could be acquired after rebooting. However, a 2.2% shift in phantom values occurred in July 1996 owing to a photomultiplier tube failure, but this did not produce a failure in the Lunar QC. The optical disc drive was replaced in July 1997. The machine failed to back up on six occasions over the last 2 years owing to software corruption and the acquired femur data were not saved on seven occasions owing to overloading of the memory buffer. In conclusion, expected hardware failure and minor software problems have occurred. We were concerned that the manufacturer's QC failed to detect a 2% shift in the phantom bone mineral density values and recommend regular measurements of the Lunar aluminum phantom in addition to the daily QC measurement of the tissue-equivalent block. We were nevertheless impressed by the long-term stability and reproducibility of the Lunar DPX alpha. PMID:11089465

  12. Portable and wide-range solid-state transmission densitometer for quality control in film radiography

    PubMed Central

    Aramburo, Javier Morales; Gonzalez, Sigifredo Solano; Toledo, Jorge Toledo

    2010-01-01

    In biology, materials science, radiography quality control or film dosimetry in radiotherapy, a transmission densitometer is useful for measurements of optical density. The design proposed here is oriented to quality control in radiographic films. The instrument described here utilizes low-cost solid-state devices and is easy to construct. The use of 1-watt white light-emitting diode in this densitometer enables low power consumption and a cold light source. Moreover, the instrument does not need a reference light, which results in decreasing the number of parts and reducing the overall size of the apparatus. PMID:20927222

  13. 21 CFR 862.2400 - Densitometer/scanner (integrating, reflectance, TLC, or radiochromatogram) for clinical use.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., TLC, or radiochromatogram) for clinical use. 862.2400 Section 862.2400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Laboratory Instruments § 862.2400 Densitometer/scanner...

  14. 21 CFR 862.2400 - Densitometer/scanner (integrating, reflectance, TLC, or radiochromatogram) for clinical use.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., TLC, or radiochromatogram) for clinical use. 862.2400 Section 862.2400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Laboratory Instruments § 862.2400 Densitometer/scanner...

  15. 21 CFR 862.2400 - Densitometer/scanner (integrating, reflectance, TLC, or radiochromatogram) for clinical use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., TLC, or radiochromatogram) for clinical use. 862.2400 Section 862.2400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Laboratory Instruments § 862.2400 Densitometer/scanner...

  16. Ultrasonic fluid densitometer having liquid/wedge and gas/wedge interfaces

    DOEpatents

    Greenwood, Margaret S.

    2000-01-01

    The present invention is an ultrasonic liquid densitometer that uses a material wedge having two sections, one with a liquid/wedge interface and another with a gas/wedge interface. It is preferred that the wedge have an acoustic impedance that is near the acoustic impedance of the liquid, specifically less than a factor of 11 greater than the acoustic impedance of the liquid. Ultrasonic signals are internally reflected within the material wedge. Density of a liquid is determined by immersing the wedge into the liquid and measuring reflections of ultrasound at the liquid/wedge interface and at the gas/wedge interface.

  17. Objective evaluation of the relative modulation transfer function of densitometers for digitisation of electron micrographs.

    PubMed

    Roseman, A M; Neumann, K

    2003-08-01

    Digitisation of images recorded on film is a crucial part of data acquisition in electron microscopy, particularly for electron cryo-microscopy of biological specimens where the contrast and signal-to-noise ratio are low. A quantitative method to evaluate and compare the quality of densitometers, as measured by the modulation transfer function (MTF), is described here. The densitometer is modelled as a linear system, the output being the convolution of the input image and a point spread function. The MTF is the magnitude of the Fourier transform of the point spread function. The relative MTF describes the quality of signal transfer with spatial frequency. It is important that fine structural details in the micrograph are digitised with a high value for the MTF which does not vary with direction. A test pattern has been generated by projecting an electron image of a grid pattern onto film. The film is scanned and a computer program measures the intensities of the diffraction orders of the repeating pattern. Three different scanners are compared, one is a point scanner and the other two are line scanners. The test can be used to check if a scanner is set up optimally, and how it compares with another scanner. PMID:12672572

  18. Applied research and development of falling-sphere densitometers payloads of improved design

    NASA Astrophysics Data System (ADS)

    Fryklund, D. H.

    1981-08-01

    Four complete falling-sphere densitometer systems were designed and launched, with generally satisfactory results, at three locations: New Mexico, Sweden, and Alaska. The task included the provision and launch responsibility for the nose cones and ejection systems for all densitometers and the provision and launch responsibility for two unique support units for the payloads flown in Sweden. Refinements were made to improve system accuracy in the calibration and data reduction techniques for the Z-axis channels of the sphere. The Z-axis amplifiers were modified to improve their performance. A wide-band accelerometer was designed and integrated into the sphere system to provide for a high resolution instrument to enable small-scale wind and turbulence studies of the high-altitude atmosphere. The sphere was reintegrated to provide for a more powerful transponder and a PCM-ranging system. A study was made to reassess the sphere configuration to reduce its gross weight. Design changes will reduce this weight by 1 lb. Additional volume was recovered for future expansion in the sphere instrumentation.

  19. Cross-Calibration and Comparison of Variability in Two Bone Densitometers in a Research Setting: The Framingham Experience

    PubMed Central

    Gagnon, David R.; McLean, Robert R.; Hannan, Marian T.; Cupples, L. Adrienne; Hogan, Mary; Kiel, Douglas P.

    2010-01-01

    New technology introduced over time results in changes in densitometers during longitudinal studies of bone mineral density (BMD). This requires that a cross-calibration process be completed to translate measurements from the old densitometer to the new one. Previously described cross-calibration methods for research settings have collected single measures on each densitometer and used linear regression to estimate cross-calibration corrections. Thus, these methods may produce corrections that have limited precision and underestimate the variability in converted BMD values. Furthermore, most prior studies have included small samples recruited from specialized populations. Increasing the sample size, obtaining multiple measures on each machine, and utilizing linear mixed models to account for between- and within-subject variability may improve cross-calibration estimates. The purpose of this study was to conduct an in vivo cross-calibration of a Lunar DPX-L with a Lunar Prodigy densitometer using a sample of 249 healthy volunteers who were scanned twice on each densitometer, without repositioning, at both the femur and spine. Scans were analyzed using both automated and manual placement of regions of interest. Wilcoxon rank-sum tests and Bland-Altman plots were used to examine possible differences between repeat scans within and across densitometers. We used linear mixed models to determine the cross-calibration equations for the femoral neck, trochanter, total hip and lumbar spine (L2-L4) regions. Results using automated and manual placement of the regions of interest did not differ significantly The DPX–L exhibited larger median absolute differences in repeat scans for femoral neck [0.016 vs. 0.012, p=0.1] and trochanter [0.011 vs. 0.009, p=0.06] BMD values compared to the Prodigy. The Bland-Altman plots revealed no statistically significant linear relation between the difference in paired measures between machines and mean BMD. In our large sample of healthy

  20. Evaluation and calibration of a Los Alamos National Laboratory L/sub III/-edge densitometer

    SciTech Connect

    McGonnagle, W.J.; Holland, M.K.; Reynolds, C.S.; Trahey, N.M.; Zook, A.C.

    1983-07-01

    The Department of Energy (DOE), New Brunswick Laboratory (NBL) has evaluated and calibrated an L/sub III/-edge densitometer for the Los Alamos National Laboratory. This prototype instrument was designed for nondestructive on-line measurement of uranium and/or plutonium solutions. The sensitivity was optimized for measuring the uranium and plutonium concentrations in mixed solutions typical of those produced by solvent extraction in the U-Pu fuel cycle. Foil assays were performed on a daily basis to monitor the measurement precision and the stability of the calibration. Traceable reference solutions prepared at NBL were used to calibrate and evaluate the system. For solutions containing approximately 50 grams of uranium and/or plutonium per liter, the relative standard deviation for the L-edge measurements was approximately 0.3%. This experimental evaluation demonstrated that the solution matrix did not influence the results. The instrument performance in a laboratory environment was excellent.

  1. Pseudo Color Densitometer Analysis-the Apollo 17/Saturn V Exhaust Plume.

    PubMed

    Orville, R E; Helsdon, J H

    1974-10-01

    Spectra of the Apollo 17/Saturn V exhaust plume have been obtained in the uv (300ndash;400 nm), visible (400-650 nm), and ir (750-790 nm) regions. Analysis of these data with a pseudo color densitometer reveals (1) a standing wave pattern in the exhaust plume characterized by a wavelength of 9 m, (2) a region of intense continuum within 40 m of the exit plane which supports previous reports of a continuum blackbody source with a peak temperature near 2600 K, (3) a region of continuum emission beyond 40 m that is not blackbody, and (4) line emissions beyond 40 m attributed to the sodium D lines and potassium. It is suggested that an interference filter centered on the sodium D lines could be used on a high speed framing camera to study the turbulent structure of the plume in the nonblackbody region. PMID:20134660

  2. A rapid, inexpensive, quantitative, general-purpose densitometer and its application to one-dimensional gel electrophoretograms.

    PubMed

    Haselgrove, J C; Lyons, G; Rubenstein, N; Kelly, A

    1985-11-01

    We describe the construction of a densitometer based on a TV camera linked to an IBM personal computer (PC) using commercially available components. We discuss some of the problems of accurate quantitative densitometry using low-cost video systems, and describe the manner in which absolute optical density values may be recorded. We describe a digital analysis routine designed to quantitate unresolved bands on noisy one-dimensional electrophoretograms. PMID:3841468

  3. Outdoor solar UVA dose assessment with EBT2 radiochromic film using spectrophotometer and densitometer measurements.

    PubMed

    Abukassem, I; Bero, M A

    2015-04-01

    Direct measurements of solar ultraviolet radiations (UVRs) have an important role in the protection of humans against UVR hazard. This work presents simple technique based on the application of EBT2 GAFCHROMIC(®) film for direct solar UVA dose assessment. It demonstrates the effects of different parts of the solar spectrum (UVB, visible and infrared) on performed UVA field measurements and presents the measurement uncertainty budget. The gradient of sunlight exposure level permitted the authors to establish the mathematical relationships between the measured solar UVA dose and two measured quantities: the first was the changes in spectral absorbance at the wavelength 633 nm (A633) and the second was the optical density (OD). The established standard relations were also applied to calculate the solar UVA dose variations during the whole day; 15 min of exposure each hour between 8:00 and 17:00 was recorded. Results show that both applied experimental methods, spectrophotometer absorbance and densitometer OD, deliver comparable figures for EBT2 solar UVA dose assessment with relative uncertainty of 11% for spectral absorbance measurements and 15% for OD measurements. PMID:25500756

  4. A prototype, glassless densitometer traceable to primary optical standards for quantitative radiochromic film dosimetry

    SciTech Connect

    Rosen, B. S. Hammer, C. G.; Kunugi, K. A.; DeWerd, L. A.; Soares, C. G.

    2015-07-15

    Purpose: To evaluate a prototype densitometer traceable to primary optical standards and compare its performance to an EPSON Expression{sup ®} 10000XL flatbed scanner (the Epson) for quantitative radiochromic film (RCF) dosimetry. Methods: A prototype traceable laser densitometry system (LDS) was developed to mitigate common film scanning artifacts, such as positional scan dependence and high noise in low-dose regions, by performing point-based measurements of RCF suspended in free-space using coherent light. The LDS and the Epson optical absorbance scales were calibrated up to 3 AU, using reference materials calibrated at a primary standards laboratory and a scanner calibration factor (SCF). Calibrated optical density (OD) was determined for 96 Gafchromic{sup ®} EBT3 film segments before and after irradiation to one of 16 dose levels between 0 and 10 Gy, exposed to {sup 60}Co in a polymethyl-methacrylate (PMMA) phantom. The sensitivity was determined at each dose level and at two rotationally orthogonal readout orientations to obtain the sensitometric response of each RCF dosimetry system. LDS rotational scanning dependence was measured at nine angles between 0°and 180°, due to the expected interference between coherent light and polarizing EBT3 material. The response curves were fit to the analytic functions predicted by two physical response models: the two-parameter single-hit model and the four-parameter percolation model. Results: The LDS and the Epson absorbance measurements were linear to primary optical standards to within 0.2% and 0.3% up to 2 and 1 AU, respectively. At higher densities, the LDS had an over-response (2.5% at 3 AU) and the Epson an under-response (3.1% and 9.8% at 2 and 3 AU, respectively). The LDS and the Epson SCF over the applicable range were 0.968% ± 0.2% and 1.561% ± 0.3%, respectively. The positional scan dependence was evaluated on each digitizer and shown to be mitigated on the LDS, as compared to the Epson. Maximum EBT3

  5. Comparison of electrical capacitance tomography and gamma densitometer measurement in viscous oil-gas flows

    SciTech Connect

    Archibong Eso, A.; Zhao, Yabin; Yeung, Hoi

    2014-04-11

    Multiphase flow is a common occurrence in industries such as nuclear, process, oil and gas, food and chemical. A prior knowledge of its features and characteristics is essential in the design, control and management of such processes due to its complex nature. Electrical Capacitance Tomography (ECT) and Gamma Densitometer (Gamma) are two promising approaches for multiphase visualization and characterization in process industries. In two phase oil and gas flow, ECT and Gamma are used in multiphase flow monitoring techniques due to their inherent simplicity, robustness, and an ability to withstand wide range of operational temperatures and pressures. High viscous oil (viscosity > 100 cP) is of interest because of its huge reserves, technological advances in its production and unlike conventional oil (oil viscosity < 100 cP) and gas flows where ECT and Gamma have been previously used, high viscous oil and gas flows comes with certain associated concerns which include; increased entrainment of gas bubbles dispersed in oil, shorter and more frequent slugs as well as oil film coatings on the walls of flowing conduits. This study aims to determine the suitability of both devices in the visualization and characterization of high-viscous oil and gas flow. Static tests are performed with both devices and liquid holdup measurements are obtained. Dynamic experiments were also conducted in a 1 and 3 inch facility at Cranfield University with a range of nominal viscosities (1000, 3000 and 7500 cP). Plug, slug and wavy annular flow patterns were identified by means of Probability Mass Function and time series analysis of the data acquired from Gamma and ECT devices with high speed camera used to validate the results. Measured Liquid holdups for both devices were also compared.

  6. Application of gamma densitometer for measurement of void fraction in liquid hydrogen moderator of HANARO cold neutron source

    NASA Astrophysics Data System (ADS)

    Kim, Myong-Seop; Choi, Jungwoon; Sun, Gwang-Min; Lee, Kye-Hong

    2009-06-01

    The void fraction in the liquid hydrogen used for the moderator of the HANARO cold neutron source (CNS) was measured by using a gamma densitometer technique. A mock-up of the HANARO CNS facility with an electric heating system as the heat source instead of radiations was constructed. The photon transmissions through the hydrogen moderator were simulated to search for an optimum experimental condition. From the simulation, it was confirmed that Am-241 was suitable for the measurement of the void fraction in the liquid hydrogen medium. A gamma densitometer using the Am-241 gamma-ray source was designed and installed at the mock-up of the CNS. The attenuation of 59.5 keV gamma-rays from the Am-241 through the hydrogen medium was measured by using an HPGe detector. The void fraction was determined using the amount of the gamma-ray attenuation. The void fractions in the hydrogen moderator were measured for stable thermo-siphon loops with several electric heat loads applied to the moderator cell of the CNS mock-up. The longitudinal distribution of the void fraction inside the moderator cell was also determined. The void fraction measured at a heat load of 720 W had values of 8-41% depending on the height from the bottom of the moderator cell. The overall void fraction was obtained by volume-weighted averaging of its longitudinal distribution. The void fraction at the nuclear heating power expected at the normal operation condition of the HANARO CNS facility was determined to be about 20%. The large uncertainty was expected in the void fraction determination by a gamma densitometer for the liquid hydrogen medium with the void fraction less than 10%. When the void fraction of the liquid hydrogen was near 20%, the uncertainty in the void fraction determination by using a gamma densitometer became relatively small, and it was regarded as an acceptable level. The measurements for the void fraction will be very useful for the design and operation of the HANARO CNS.

  7. Rodent bone densitometer on the International Space Station: Instrument design and performance

    NASA Astrophysics Data System (ADS)

    Vellinger, John C.; Barton, Kenneth; Faget, Paul; Todd, Paul; Boland, Eugene

    2016-07-01

    The study of bone loss dynamics, mechanisms and countermeasures has been a publicly stated purpose of biomedical research aboard the International Space Station. Rodent research has always played a major role in terrestrial laboratories studying bone loss. The "gold standard" for assessing bone loss in human patients has been dual-energy x-ray absorptiometry (DEXA). DEXA is also widely applied to the study of bone loss in laboratory animals, so this technology has been added to the ISS inventory of analytical tools in the form of the ISS Bone Densitometer (BD) designed, constructed, tested and integrated by Techshot, Inc. (Greenville, Indiana, USA). The BD is a re-packaged COTS device known as PIXImus (GE-Lunar, USA), which was installed on ISS in November 2014 after launching on SpaceX-4. To facilitate operations in microgravity and to meet spaceflight facility and safety requirements the commercial x-ray source, control electronics and imaging system were modified and packaged by Techshot into a drawer that fits into a single EXPRESS Locker replacement. A space-rated "Exam Box" is also supplied for containment of the anesthetized subject during transfer into the BD and during exposure. The commercial software package controls four paired-energy exposures, 80 and 35 kV, and applies DEXA algorithms to the fluorescence images and displays bone mineral density (BMD), bone mineral content, lean mass, fat mass, total mass and per cent fat. The BD is therefore also a means for measuring mass and body composition making it a versatile tool for many types of rodent studies on orbit. The BD has been operated multiple times on orbit, and its performance has not differed significantly from its performance on the ground. It has been shown to measure body mass with a precision of +/- 0.1 g and on-orbit accuracy of -0.3 g. It is expected to detect BMD losses of approximately 2%. The image data are stored in a manner that allows post-test data analysis especially including the

  8. Small animal bone density and morphometry analysis with a dual energy x-ray absorptiometry bone densitometer using a 2D digital radiographic detector

    NASA Astrophysics Data System (ADS)

    Boudousq, V.; Bordy, T.; Gonon, G.; Dinten, J. M.

    2005-04-01

    The LEXXOS (DMS, Montpellier, France) is the first axial and total body cone beam bone densitometer using a 2D digital radiographic detector. Technical principles and performances for BMD measurements have been presented in previous papers. Bone densitometers are also used on small animals for drug development. In this paper, we show how the LEXXOS system can be adapted to small animals examinations, and its performances are evaluated. At first, in order to take advantage of the whole area of the digital flat panel X-ray detector, the geometrical configuration has been adapted. Secondly, as small animals present low BMD, a specific dual energy calibration has been defined. This adapted system has then been evaluated on two sets of mice: six reference mice and six ovariectomized mice. Each month, these two populations have been examined and the total body BMD has been measured. This evaluation has shown that the right order of BMD magnitude has been obtained and, as expected, BMD increases on the two sets until age of puberty and after this period, decreases significantly for the ovariectomized set. Moreover, the bone image obtained by dual energy processing on LEXXOS presents a radiographic image quality providing with useful complementary information on bone morphometry and architecture.

  9. Online capacitive densitometer

    DOEpatents

    Porges, Karl G.

    1990-01-01

    This invention is an apparatus for measuring fluid density of mixed phase fluid flow. The apparatus employs capacitive sensing of the mixed phased flow combined with means for uniformizing the electric field between the capacitor plates to account for flow line geometry. From measurement of fluid density, the solids feedrate can be ascertained.

  10. Ultrasonic bone densitometer

    NASA Technical Reports Server (NTRS)

    Hoop, J. M.

    1972-01-01

    Human bone density changes can be determined by a device originally developed for in-flight testing of astronauts' bones during extended space missions. Device is comparable in size, weight and power consumption to portable television set.

  11. Ultrasonic bone densitometer

    NASA Technical Reports Server (NTRS)

    Hoop, J. M. (Inventor)

    1974-01-01

    A device, for measuring the density of a bone structure so as to monitor the calcium content, is described. A pair of opposed spaced ultrasonic transducers are held within a clamping apparatus closely adjacent the bone being analyzed. These ultrasonic transducers incude piezoelectric crystals shaped to direct signals through the bone encompassed in the heel and finger of the subject being tested. A pulse generator is coupled to one of the transducers and generates an electric pulse for causing the transducers to generate an ultrasonic sound wave which is directed through the bone structure to the other transducer. An electric circuit, including an amplifier and a bandpass filter couples the signals from the receiver transducer back to the pulse generator for retriggering the pulse generator at a frequency proportional to the duration that the ultrasonic wave takes to travel through the bone structure being examined.

  12. High resolution ultrasonic densitometer

    SciTech Connect

    Dress, W.B.

    1983-01-01

    The velocity of torsional stress pulses in an ultrasonic waveguide of non-circular cross section is affected by the temperature and density of the surrounding medium. Measurement of the transit times of acoustic echoes from the ends of a sensor section are interpreted as level, density, and temperature of the fluid environment surrounding that section. This paper examines methods of making these measurements to obtain high resolution, temperature-corrected absolute and relative density and level determinations of the fluid. Possible applications include on-line process monitoring, a hand-held density probe for battery charge state indication, and precise inventory control for such diverse fluids as uranium salt solutions in accountability storage and gasoline in service station storage tanks.

  13. Online capacitive densitometer

    DOEpatents

    Porges, K.G.

    1988-01-21

    This invention is an apparatus for measuring fluid density of mixed phase fluid flow. The apparatus employs capacitive sensing of the mixed phased flow combined with means for uniformizing the electric field between the capacitor plates to account for flow line geometry. From measurement of fluid density, the solids feedrate can be ascertained. 7 figs.

  14. Miniature X-Ray Bone Densitometer

    NASA Technical Reports Server (NTRS)

    Charles, Harry K., Jr.

    1999-01-01

    The purpose of the Dual Energy X-ray Absorptiometry (DEXA) project is to design, build, and test an advanced X-ray absorptiometry scanner capable of being used to monitor the deleterious effects of weightlessness on the human musculoskeletal system during prolonged spaceflight. The instrument is based on the principles of dual energy x-ray absorptiometry and is designed not only to measure bone, muscle, and fat masses but also to generate structural information about these tissues so that the effects on mechanical integrity may be assessed using biomechanical principles. A skeletal strength assessment could be particularly important for an astronaut embarking on a remote planet where the consequences of a fragility fracture may be catastrophic. The scanner will employ multiple projection images about the long axis of the scanned subject to provide geometric properties in three dimensions, suitable for a three-dimensional structural analysis of the scanned region. The instrument will employ advanced fabrication techniques to minimize volume and mass (100 kg current target with a long-term goal of 60 kg) of the scanner as appropriate for the space environment, while maintaining the required mechanical stability for high precision measurement. The unit will have the precision required to detect changes in bone mass and geometry as small as 1% and changes in muscle mass as small as 5%. As the system evolves, advanced electronic fabrication technologies such as chip-on-board and multichip modules will be combined with commercial (off-the-shelf) parts to produce a reliable, integrated system which not only minimizes size and weight, but, because of its simplicity, is also cost effective to build and maintain. Additionally, the system is being designed to minimize power consumption. Methods of heat dissipation and mechanical stowage (for the unit when not in use) are being optimized for the space environment.

  15. Bell nipple densitometer method and apparatus

    SciTech Connect

    Rochon, R.W.; Sneed, J.W. Jr.

    1983-10-11

    A method and apparatus for continuously determining the amount of entrained gases and drilling fluid before the entrained gas is released to the atmosphere whereby differential pressures at vertically spaced locations in a bell nipple are monitored to determine changes in the weight of drilling fluid due to entrained gases.

  16. New Compton densitometer for measuring pulmonary edema

    SciTech Connect

    Loo, B.W.; Goulding, F.S.; Simon, D.S.

    1985-10-01

    Pulmonary edema is the pathological increase of extravascular lung water found most often in patients with congestive heart failure and other critically ill patients who suffer from intravenous fluid overload. A non-invasive lung density monitor that is accurate, easily portable, safe and inexpensive is needed for clinical evaluation of pulmonary edema. Other researchers who have employed Compton scattering techniques generally used systems of extended size and detectors with poor energy resolution. This has resulted in significant systematic biases from multiply-scattered photons and larger errors in counting statistics at a given radiation dose to the patient. We are proposing a patented approach in which only backscattered photons are measured with a high-resolution HPGe detector in a compact system geometry. By proper design and a unique data extraction scheme, effects of the variable chest wall on lung density measurements are minimized. Preliminary test results indicate that with a radioactive source of under 30 GBq, it should be possible to make an accurate lung density measurement in one minute, with a risk of radiation exposure to the patient a thousand times smaller than that from a typical chest x-ray. The ability to make safe, frequent lung density measurements could be very helpful for monitoring the course of P.E. at the hospital bedside or outpatient clinics, and for evaluating the efficacy of therapy in clinical research. 6 refs., 5 figs.

  17. The development of a Compton lung densitometer

    SciTech Connect

    Loo, B.W.; Goulding, F.S.; Madden, N.W.; Simon, D.S.

    1988-11-01

    A field instrument is being developed for the non-invasive determination of absolute lung density using unique Compton backscattering techniques. A system consisting of a monoenergetic gamma-ray beam and a shielded high resolution high-purity-germanium (HPGe) detector in a close-coupled geometry is designed to minimize errors due to multiple scattering and uncontrollable attenuation in the chestwall. Results of studies on system performance with phantoms, the optimization of detectors, and the fabrication of a practical gamma-ray source are presented. 3 refs., 6 figs., 2 tabs.

  18. [Software Design for a Portable Ultrasound Bone Densitometer].

    PubMed

    Deng, Jiangjun; Ding, Jie; Xu, Shijie; Geng, Ruihua; He, Aijun

    2015-10-01

    In order to meet the requirements of ultrasound bone density measurement, we designed a sofware based on Visual Studio C+ + 2008. The software includes interface design, acquisition and control, data processing and parameter extraction, data storage and printing. Excellent human-computer interface (HCI) will give users a convenient experience. Auto gain control (AGC) and digital filter can improve the precision effectively. In addition, we can observe waveform clearly in real time. By using USB communication, we can send control commands to the acquisition and get data effectively, which can shorten the measuring time. Then we calculated the speed of sound (SOS) and broadband ultrasound attenuation (BUA). Patients' information can be accessed by using XML document. Finally, the software offers printing function. PMID:26964306

  19. Liquid hydrogen densitometer utilizes open-ended microwave cavity

    NASA Technical Reports Server (NTRS)

    Smetana, J.; Wenger, N. C.

    1967-01-01

    Open-ended microwave cavity directly measures the density of flowing liquid, gaseous, or two-phase hydrogen. Its operation is based on derived relations between the cavity resonant frequency and the dielectric constant and density of hydrogen.

  20. A new Compton densitometer for measuring pulmonary edema

    SciTech Connect

    Loo, B.W.; Goulding, F.S.; Simon, S.

    1986-02-01

    Pulmonary edema (PE) is the pathological increase of extravascular lung water found most often in patients with congestive heart failure and other critically ill patients who suffer from intravenous fluid overload. The chest x-ray, the standard method for validating the presence of PE, is neither quantitative nor sensitive. A non-invasive lung density monitor that is accurate, easily portable, safe and inexpensive is needed for clinical use. To deal with the problem of attenuation along the beam paths, previous gamma-ray techniques require simultaneous measurement of transmitted and scattered beams. Since multiple scattering is a strong function of the density of the scattering medium and the mass distribution within the detection geometry, there will be inherent uncertainties in the system calibration unless it is performed on a body structure closely matched to that of each individual patient. Other researchers who have employed Compton scattering techniques generally used systems of extended size and detectors with poor energy resolution. This has resulted in significant systematic biases from multiply-scattered photons and larger errors in counting statistics at a given radiation dose to the patient. We are proposing a patented approach in which only backscattered photons are measured with a high-resolution HPGe detector in a compact system geometry. By proper design and a unique data extraction scheme, effects of the variable chest wall on lung density measurements are minimized. Preliminary test results indicate that with a radioactive source of under 30 GBq, it should be possible to make an accurate lung density, measurement in one minute, with a risk of radiation exposure to the patient a thousand times smaller than that from a typical chest x-ray.

  1. CLINICAL ASSESSMENT OF THE 1/3rd RADIUS USING A NEW DESKTOP ULTRASONIC BONE DENSITOMETER

    PubMed Central

    Stein, Emily M.; Rosete, Fernando; Young, Polly; Kamanda-Kosseh, Mafo; McMahon, Donald J.; Luo, Gangming; Kaufman, Jonathan J.; Shane, Elizabeth; Siffert, Robert S.

    2012-01-01

    The objectives of this study were to evaluate the capability of a novel ultrasound device to clinically estimate bone mineral density (BMD) at the 1/3rd radius. The device rests on a desktop and is portable, and permits real-time evaluation of the radial BMD. The device measures two (2) net time delay (NTD) parameters, NTDDW and NTDCW. NTDDW is defined as the difference between the transit time of an ultrasound pulse to travel through soft-tissue, cortex and medullary cavity, and the transit time through soft tissue only of equal overall distance. NTDCW is defined as the difference between the transit time of an ultrasound pulse to travel through soft-tissue and cortex only, and the transit time through soft tissue only again of equal overall distance. The square root of the product of these two parameters is a measure of the radial BMD at the 1/3rd location as measured by dual-energy x-ray absorptiometry (DXA). A clinical IRB-approved study measured ultrasonically sixty adults at the 1/3rd radius. BMD was also measured at the same anatomical site and time using DXA. A linear regression using NTD produced a linear correlation coefficient of 0.93 (P<0.001). These results are consistent with previously reported simulation and in vitro studies. In conclusion, although x-ray methods are effective in bone mass assessment, osteoporosis remains one of the largest undiagnosed and under-diagnosed diseases in the world today. The research described here should enable significant expansion of diagnosis and monitoring of osteoporosis through a desktop device that ultrasonically assesses bone mass at the 1/3rd radius. PMID:23312957

  2. 21 CFR 862.2400 - Densitometer/scanner (integrating, reflectance, TLC, or radiochromatogram) for clinical use.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND... a photocell measurement of the light transmission through a given area of the medium or, in the...

  3. Operators manual for microdensitometer control program densitometer model PDS-1010G (modified). Program trace version 3B (section 3)

    NASA Technical Reports Server (NTRS)

    Title, A. M.

    1974-01-01

    The PDS-1010G microdensitometer is run under the control of a PDP-11 program called TRACE. This program gives the operator vary flexible control over the machine functions. Most commands are passed to the computer through either the Tektronix 4010 terminal or the teletype, as selected by the position of the LOCAL/LINE rocker switch above the 4010 keyboard. (LINE places the 4010 in control; LOCAL transfers control to the teletype. In general, the teletype is used when the operator desires a permanent record of the operator-computer dialogue.) A small number of control functions are requested by setting switches on the computer front panel.

  4. Optimum design of multi-layer K-edge filter and multi-stage detectors for triple energy bone densitometer

    NASA Astrophysics Data System (ADS)

    Mazoochi, Alireza; Rahmani, Faezeh; Abbasi Davani, Fereydoun; Ghaderi, Ruhollah

    2014-03-01

    Dual X-ray bone densitometry may cause some errors in diagnosis due to heterogeneous distribution of adipose tissue. It is necessary to develop a more accurate technique to consider the effects of fat. In this research, a triple energy X-ray method has been introduced and conceptual design of a system consisting of 160 kV X-ray tube, multi-layer K-edge filter and multi-stage detector has been presented. Design calculations have been performed using MCNP4C Monte Carlo code to select the type of filters and detectors with the best thicknesses for better distinguishing materials. The energy peaks (37 keV, 50 keV and 105 keV) can be separated optimally with a multi-layer filter composed of barium (170 μm) and gadolinium (100 μm) as the first and second layers, respectively which are coated on a 1 mm aluminum plate placed between the source and tissue. The transmitted photons have been counted by a multi-stage linear array of detectors consisting of ZnSe(Te) and CsI(Tl) with 400 μm and 5 mm thicknesses, respectively. Monte Carlo simulations show that the triple energy X-ray technique has better accuracy than that of the standard dual energy X-ray technique.

  5. Quantitative Determination of Photosynthetic Pigments in Green Beans Using Thin-Layer Chromatography and a Flatbed Scanner as Densitometer

    ERIC Educational Resources Information Center

    Valverde, Juan; This, Herve; Vignolle, Marc

    2007-01-01

    A simple method for the quantitative determination of photosynthetic pigments extracted from green beans using thin-layer chromatography is proposed. Various extraction methods are compared, and it is shown how a simple flatbed scanner and free software for image processing can give a quantitative determination of pigments. (Contains 5 figures.)

  6. Microdensitometer errors: Their effect on photometric data reduction

    NASA Technical Reports Server (NTRS)

    Bozyan, E. P.; Opal, C. B.

    1984-01-01

    The performance of densitometers used for photometric data reduction of high dynamic range electrographic plate material is analyzed. Densitometer repeatability is tested by comparing two scans of one plate. Internal densitometer errors are examined by constructing histograms of digitized densities and finding inoperative bits and differential nonlinearity in the analog to digital converter. Such problems appear common to the four densitometers used in this investigation and introduce systematic algorithm dependent errors in the results. Strategies to improve densitometer performance are suggested.

  7. Cross-Calibration of GE Healthcare Lunar Prodigy and iDXA Dual-Energy X-Ray Densitometers for Bone Mineral Measurements.

    PubMed

    Saarelainen, J; Hakulinen, M; Rikkonen, T; Kröger, H; Tuppurainen, M; Koivumaa-Honkanen, H; Honkanen, R; Hujo, M; Jurvelin, J S

    2016-01-01

    In long-term prospective studies, dual-energy X-ray absorptiometry (DXA) devices need to be inevitably changed. It is essential to assess whether systematic differences will exist between measurements with the new and old device. A group of female volunteers (21-72 years) underwent anteroposterior lumbar spine L2-L4 (n = 72), proximal femur (n = 72), and total body (n = 62) measurements with the Prodigy and the iDXA scanners at the same visit. The bone mineral density (BMD) measurements with these two scanners showed a high linear association at all tested sites (r = 0.962-0.995; p < 0.0001). The average iDXA BMD values were 1.5%, 0.5%, and 0.9% higher than those of Prodigy for lumbar spine (L2-L4) (p < 0.0001), femoral neck (p = 0.048), and total hip (p < 0.0001), respectively. Total body BMD values measured with the iDXA were -1.3% lower (p < 0.0001) than those measured with the Prodigy. For total body, lumbar spine, and femoral neck, the BMD differences as measured with these two devices were independent of subject height and weight. Linear correction equations were developed to ensure comparability of BMD measurements obtained with both DXA scanners. Importantly, use of equations from previous studies would have increased the discrepancy between these particular DXA scanners, especially at hip and at spine. PMID:27239366

  8. Cross-Calibration of GE Healthcare Lunar Prodigy and iDXA Dual-Energy X-Ray Densitometers for Bone Mineral Measurements

    PubMed Central

    Saarelainen, J.; Hakulinen, M.; Rikkonen, T.; Kröger, H.; Tuppurainen, M.; Koivumaa-Honkanen, H.; Honkanen, R.; Hujo, M.; Jurvelin, J. S.

    2016-01-01

    In long-term prospective studies, dual-energy X-ray absorptiometry (DXA) devices need to be inevitably changed. It is essential to assess whether systematic differences will exist between measurements with the new and old device. A group of female volunteers (21–72 years) underwent anteroposterior lumbar spine L2–L4 (n = 72), proximal femur (n = 72), and total body (n = 62) measurements with the Prodigy and the iDXA scanners at the same visit. The bone mineral density (BMD) measurements with these two scanners showed a high linear association at all tested sites (r = 0.962–0.995; p < 0.0001). The average iDXA BMD values were 1.5%, 0.5%, and 0.9% higher than those of Prodigy for lumbar spine (L2–L4) (p < 0.0001), femoral neck (p = 0.048), and total hip (p < 0.0001), respectively. Total body BMD values measured with the iDXA were −1.3% lower (p < 0.0001) than those measured with the Prodigy. For total body, lumbar spine, and femoral neck, the BMD differences as measured with these two devices were independent of subject height and weight. Linear correction equations were developed to ensure comparability of BMD measurements obtained with both DXA scanners. Importantly, use of equations from previous studies would have increased the discrepancy between these particular DXA scanners, especially at hip and at spine. PMID:27239366

  9. Flowmeter for gas-entrained solids flow

    DOEpatents

    Porges, Karl G.

    1990-01-01

    An apparatus and method for the measurement of solids feedrate in a gas-entrained solids flow conveyance system. The apparatus and method of the present invention include a vertical duct connecting a source of solids to the gas-entrained flow conveyance system, a control valve positioned in the vertical duct, and a capacitive densitometer positioned along the duct at a location a known distance below the control valved so that the solid feedrate, Q, of the gas entrained flow can be determined by Q=S.rho..phi.V.sub.S where S is the cross sectional area of the duct, .rho. is the density of the solid, .phi. is the solid volume fraction determined by the capacitive densitometer, and v.sub.S is the local solid velocity which can be inferred from the konown distance of the capacitive densitometer below the control valve.

  10. High-throughput film-densitometry: An efficient approach to generate large data sets

    SciTech Connect

    Typke, Dieter; Nordmeyer, Robert A.; Jones, Arthur; Lee, Juyoung; Avila-Sakar, Agustin; Downing, Kenneth H.; Glaeser, Robert M.

    2004-07-14

    A film-handling machine (robot) has been built which can, in conjunction with a commercially available film densitometer, exchange and digitize over 300 electron micrographs per day. Implementation of robotic film handling effectively eliminates the delay and tedium associated with digitizing images when data are initially recorded on photographic film. The modulation transfer function (MTF) of the commercially available densitometer is significantly worse than that of a high-end, scientific microdensitometer. Nevertheless, its signal-to-noise ratio (S/N) is quite excellent, allowing substantial restoration of the output to ''near-to-perfect'' performance. Due to the large area of the standard electron microscope film that can be digitized by the commercial densitometer (up to 10,000 x 13,680 pixels with an appropriately coded holder), automated film digitization offers a fast and inexpensive alternative to high-end CCD cameras as a means of acquiring large amounts of image data in electron microscopy.

  11. Dosimetric properties of improved GafChromic films for seven different digitizers.

    PubMed

    Devic, Slobodan; Seuntjens, Jan; Hegyi, Gyorgy; Podgorsak, Ervin B; Soares, Christopher G; Kirov, Assen S; Ali, Imad; Williamson, Jeffrey F; Elizondo, Angel

    2004-09-01

    Two recently introduced GafChromic film models, HS and XR-T, have been developed as more sensitive and uniform alternatives to GafChromic MD-55-2 film. The HS model has been specifically designed for measurement of absorbed dose in high-energy photon beams (above 1 MeV), while the XR-T model has been introduced for dose measurements of low energy (0.1 MeV) photons. The goal of this study is to compare the sensitometric curves and estimated dosimetric uncertainties associated with seven different GafChromic film dosimetry systems for the two new film models. The densitometers tested are: LKB Pharmacia UltroScan XL, Molecular Dynamics Personal Densitometer, Nuclear Associates Radiochromic Densitometer Model 37-443, Photoelectron Corporation CMR-604, Laser Pro 16, Vidar VXR-16, and AGFA Arcus II document scanner. Pieces of film were exposed to different doses in a dose range from 0.5 to 50 Gy using 6 MV photon beam. Functional forms for dose vs net optical density have been determined for each of the GafChromic film-dosimetry systems used in this comparison. Two sources of uncertainties in dose measurements, governed by the experimental measurement and calibration curve fit procedure, have been compared for the densitometers used. Among the densitometers tested, it is found that for the HS film type the uncertainty caused by the experimental measurement varies from 1% to 3% while the calibration fit uncertainty ranges from 2% to 4% for doses above 5 Gy. Corresponding uncertainties for XR-T film model are somewhat higher and range from 1% to 5% for experimental and from 2% to 7% for the fit uncertainty estimates. Notwithstanding the significant variations in sensitivity, the studied densitometers exhibit very similar precision for GafChromic film based dose measurements above 5 Gy. PMID:15487718

  12. Modern differential pressure gas counter (WIGZ) measurement

    NASA Astrophysics Data System (ADS)

    Brandt, O.

    1985-07-01

    The differential pressure gas counter facility developed to measure gas flow rate on orifice plates in the pipe system transporting Soviet gas to West Germany and France was equipped with small computers which record all the parameters of a measuring system and calculate the standard volume and the quantity of heat. These parameters are used to calibrate the facility. The differential pressure indicators and operating densitometers, the standard densitometers, pressure and temperature sensors, and calorific value indicators are described. The operation of and processing by the 16-bit microprocessor computers of all parameters are summarized. The central computer and the performance recording facility are presented.

  13. Accommodating brightness and exposure levels in densitometry of stained polyacrylamide electrophoresis gels

    SciTech Connect

    Tan, Han Yen; Ng, Tuck Wah; Liew, Oi Wah

    2010-03-20

    Flatbed scanner densitometers can be operated under various illumination and recording exposure levels. In this work, we show that optical density measurement accuracy, sensitivity, and stability of stained polyacrylamide electrophoresis gel densitometry are crucially dependent on these two factors (brightness and exposure level), notwithstanding that the source is monochromatic, spatially uniform, and the measurements are made using an accurately calibrated step wedge in tandem. We further outline a method to accommodate the intensity deviations over a range of illumination and exposure levels in order to maintain sensitivity and repeatability in the computed optical densities. Comparisons were also made with results from a commercial densitometer.

  14. Use of a variable exposure photographic pyrometer to measure surface temperatures on a hemispherical-face model

    NASA Technical Reports Server (NTRS)

    Kantsios, A. G.; Henley, W. C., Jr.; Snow, W. L.

    1982-01-01

    The use of a photographic pyrometer for nonintrusive measurement of high temperature surfaces in a wind tunnel test is described. The advantages of the pyrometer for measuring surfaces whose unique shape makes use of thermocouples difficult are pointed out. The use of computer operated densitometers or optical processors for the data reduction is recommended.

  15. AN EVALUATION OF TWO GROUND-BASED CROWN CLOSURE ESTIMATION TECHNIQUES COMPARED TO CROWN CLOSURE ESTIMATES DERIVED FROM HIGH RESOLUTION IMAGERY

    EPA Science Inventory

    Two ground-based canopy closure estimation techniques, the Spherical Densitometer (SD) and the Vertical Tube (VT), were compared for the effect of deciduous understory on dominant/co-dominant crown closure estimates in even-aged loblolly (Pinus taeda) pine stands located in the N...

  16. AN EVALUATION OF TWO GROUND-BASED CROWN CLOSURE ESTIMATION TECHNIQUES COMPARED TO CROWN CLOSURE ESTIMATES DERIVED FROM HIGH RESOLUTION IMAGERY

    EPA Science Inventory

    Two ground-based canopy closure estimation techniques, the Spherical Densitometer (SD) and the Vertical Tube (VT), were compared for the effect of deciduous understory on dominantlco-dominant crown closure estimates in even-aged loblolly (Pinus taeda) pine stands located in the N...

  17. Instrument continuously measures density of flowing fluids

    NASA Technical Reports Server (NTRS)

    Jacobs, R. B.; Macinko, J.; Miller, C. E.

    1967-01-01

    Electromechanical densitometer continuously measures the densities of either single-phase or two-phase flowing cryogenic fluids. Measurement is made on actual flow. The instrument operates on the principle that the mass of any vibrating system is a primary factor in determining the dynamic characteristics of the system.

  18. Oilfield liquid measurements for Sarawak Shell Bhd and Petronas Carigali in Baram delta area

    SciTech Connect

    Pushparatnam, E. ); Teo, C.K. )

    1988-01-01

    This paper describes the measurement of crude oil volume in an oil/water mixture that discharges from an oilfield. Measurement is carried out using a turbine meter, a densitometer and a flowcomputer. The system is capable of determining the volume of crude oil in a flowing stream of a crude oil/water mixture within 2% of the total liquid volume.

  19. System requirements for one-time-use ENRAF control panel software

    SciTech Connect

    HUBER, J.H.

    1999-08-19

    An Enraf Densitometer is installed on tank 241-AY-102. The Densitometer will frequently be tasked to obtain and log density profiles. The activity can be effected a number of ways. Enraf Incorporated provides a software package called ''Logger18'' to its customers for the purpose of in-shop testing of their gauges. Logger18 is capable of accepting an input file which can direct the gauge to obtain a density profile for a given tank level and bottom limit. Logger18 is a complex, DOS based program which will require trained technicians and/or tank farm entries to obtain the data. ALARA considerations have prompted the development of a more user-friendly, computer-based interface to the Enraf densitometers. This document records the plan by which this new Enraf data acquisition software will be developed, reviewed, verified, and released. This plan applies to the development and implementation of a one-time-use software program, which will be called ''Enraf Control Panel.'' The software will be primarily used for remote operation of Enraf Densitometers for the purpose of obtaining and logging tank product density profiles.

  20. Measurement And Optimalization Of The Mtf's Of The Microradiographic Method And Its Subsystems

    NASA Astrophysics Data System (ADS)

    de Jong, E. de Josselin; ten Bosch, J. J.

    1985-03-01

    Contactmicroradiography produces an X-ray absorbance image of mineralized tissue slices. We use it to calculate the mineral content in tissue from the absorbance data of thin tooth sections as a function of depth in the tissue. This paper gives a complete analysis of the loss of detail caused by the microradiographic subsystems, describing this loss with the Modulation Transfer Function (MTF). Images (CuKaradiation) of thin test objects with a sharp edge were made on holographic film; an aluminium stepwedge was used to calibrate the film. Densitometric tracings of the images were fed into a microcomputer. The dose-density relation of the film was approximated by a 3rd degree polynomial using the stepwedge data. The resulting curve was used to convert the densitometric data of the slice into X-ray absorbance data. To filter out the film grain noise, 20 microradiograms were made of the same object and their edge scans were averaged. The resulting Edge Spread Function (ESF) was transformed into the MTF using standard techniques. Thus the MTF of the total method was obtained, using a 100 pm thick Al slab as object. The combined MTF of the densitometer together with the film was found with a 27 pm thick Cu slab as object, closely pressed to the film. The densitometer MTF was obtained using a knife edge as object in the densitometer. The results show that the total loss of spatial detail depends on the contributions of the X-ray projection geometry (projection subsystem), the film emulsion (film subsystem) and densitometer window width (densitometer subsystem). The MTF's of the individual subsystems were calculated from the measured combined MTF's assuming that the imaging subsystems are linear. After optimalization of the MTF's of the subsystems the maximum transmitted spatial frequency of the method was found to be 330 lines per mm.

  1. Sounding rocket flight report, MUMP 9 and MUMP 10

    NASA Technical Reports Server (NTRS)

    Grassl, H. J.

    1971-01-01

    The results of the launching of two-Marshall-University of Michigan Probes (MUMP 9 and MUMP 10), Nike-Tomahawk sounding rocket payloads, are summarized. The MUMP is similar to the thermosphere probe, an ejectable instrument package for studying the variability of the earth's atmospheric parameters. The MUMP 9 payload included an omegatron mass analyzer, a molecular fluorescence densitometer, a mini-tilty filter, and a lunar position sensor. This complement of instruments permitted the determination of the molecular nitrogen density and temperature in the altitude range from approximately 143 to 297 km over Wallops Island, Virginia, during January 1971. The MUMP 10 payload included an omegatron mass analyzer, an electron temperature probe, a cryogenic densitometer, and a solar position sensor. These instruments permitted the determination of the molecular nitrogen density and temperature and the charged particle density and temperature in the altitude range from approximately 145 to 290 km over Wallops Island during the afternoon preceding the MUMP 9 launch.

  2. Visual and photographic white light flare observations of 4 July 1974. [of solar atmosphere

    NASA Technical Reports Server (NTRS)

    Feibelman, W. A.

    1974-01-01

    Visual impressions and a photograph of an intense white-light flare are presented. A densitometer trace across the July 4, 1974, flare showing relative intensity of the white-light flare, photosphere, and umbra is also shown. A second white-light flare is suspected on a photograph taken 4-3/4 hr later. Both flares coincide in time with major H alpha-flare activity.

  3. Proposal to evaluate the use of ERTS-A imagery in mapping and managing soil and range resources in the Sand Hills Region of Nebraska

    NASA Technical Reports Server (NTRS)

    Drew, J. V. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. There appears to be a direct relationship between densitometry values obtained with MSS band 5 imagery and forage density for those range sites measured on the imagery, provided site category identification is indicated by other forms of imagery or ground truth. Overlap of density values for different site categories with differing forage condition classes does not allow assigning a given forage density value for a given densitometer value unless the range site category is known.

  4. Densitometry of ERTS-1 imagery to access vegetation change

    NASA Technical Reports Server (NTRS)

    Ashley, M. D.; Rea, J.

    1974-01-01

    Density measurements of ERTS-1 multispectral scanner (MSS) imagery can be used to evaluate phenological changes in vegetation. It was found that the density ratios for MSS bands 5 and 7 best characterize vegetation change. The ratio increases with vegetative progression and decreases with vegetative recession. The use of a densitometer aperture as small as 0.4 mm does not adversely affect the accuracy of readings on forest sites.

  5. Features of X-ray Absorption Densitometry of Large-size Objects with Variable Thickness

    NASA Astrophysics Data System (ADS)

    Osipov, S.; Chakhlov, S.; Osipov, O.; Badin, S.; Abashkin, A.

    2016-01-01

    Features of formation and processing of the primary radiometric signals in the digital high-energy X-ray absorption densitometers for the homogeneous objects with variable thickness are examined. The densitometer's equation based on the polynomial approximation of the object's ray thickness dependence from its mass thickness is proposed. Guidance to select the capacity of the analog-digital converter is given. There is one example of the densitometer's equation coefficients calculation to examine the carbon, aluminum and steel wares with the mass density from 15 to 80 g/cm2. It was shown that disagreement of the experimental and estimated values of the ray thickness for the similar mass thicknesses of the testing object is conditioned by the scattered radiation. On the high-energy digital radiography set with the X-ray source - the betatron MIB-4.5/9 the accuracy of the experimental estimation of the density was within 0.0086 g/cm3 for the steel ware thickness from 25 to 100 mm.

  6. Field test of New TASTEX system for plutonium product verification at the Tokai Reprocessing Plant

    SciTech Connect

    Kuno, Y.; Shigeoka, K.; Nishida, K.; Ikeda, H.; Hayashi, N.; Wachi, I.; Hsue, S.T.; Sprinkle, J.K.; Gunnink, R.; Ruhter, W.D.

    1988-01-01

    This report describes the field test results of the New TASTEX system. This system consisting of the high resolution gamma spectrometer and the k-edge densitometer can measure both isotopic abundances and concentration of plutonium simultaneously. Entire system is controlled by the multichannel analyzer and a multi-user computer. The system was designed and built under the Japan Support Program for Agency Safeguards (JASPAS). The software of this system developed at LANL and LLNL has been installed in the system assembled at the Tokai reprocessing plant (TRP) in July 1985. In the course of campaigns from 1985 until 1988, field tests have been carried out on plutonium product solutions of TRP. The results of plutonium concentration and isotopic abundances obtained by the k-edge densitometer and the high resolution gamma spectrometer (HRGS) have been compared with those by controlled potential coulometer and mass spectrometer respectively. Precision of plutonium determination with k-edge densitometer is estimated approximately 0.7% and 1.0% for the freshly processed plutonium and the aged plutonium respectively. The scatters in the relative differences between HRGS and the destructive analysis (DA) detected on the results of freshly processed plutonium sample were 1.6%, 0.4%, 0.5%, 1.1%, 8.0% for Pu-238, Pu-239, Pu-240, Pu-241, and Pu-242 respectively, whereas those on the results of aged sample were 1.4%, 0.5%, 1.1%, 1.1% for Pu-238, Pu-239, Pu-240, and Pu-241 respectively. 9 refs., 15 figs., 7 tabs.

  7. Bone mineral measurements: a comparison of delayed gamma neutron activation, dual-energy X-ray absorptiometry and direct chemical analysis.

    PubMed

    Economos, C D; Nelson, M E; Fiatarone Singh, M A; Kehayias, J J; Dallal, G E; Heymsfield, S B; Wang, J; Yasumura, S; Ma, R; Pierson, R N

    1999-01-01

    A system in vitro consisting of a femur from a cadaver and soft-tissue equivalent material was used to test the agreement between several techniques for measuring bone mineral. Calcium values measured by delayed gamma neutron activation (DGNA) and bone mineral content (BMC) by Lunar, Hologic and Norland dual-energy X-ray absorptiometers (DXA) were compared with calcium and ash content determined by direct chemical analysis. To assess the effect of soft-tissue thickness on measurements of bone mineral, we had three phantom configurations ranging from 15.0 to 26.0 cm in thickness, achieved by using soft-tissue equivalent overlays. Chemical analysis of the femur gave calcium and ash content values of 61.83 g +/- 0.51 g and 154.120 +/- 0.004 g, respectively. Calcium measured by DGNA did not differ from the ashed amount of calcium at any of the phantom configurations. The BMC measured by DXA was significantly higher, by 3-5%, than the amount determined by chemical analysis for the Lunar densitometer and significantly lower, by 3-6%, for the Norland densitometer (p<0.001-0.024), but only 1% lower (not significant) for the Hologic densitometer. DXA instruments showed a decreasing trend in BMC as the thickness increased from 20.5 to 26.0 cm (p<0.05). However, within the entire thickness range (15.0-26.0 cm), the overall influence of thickness on BMC by DXA was very small. These findings offer insight into the differences in these currently available methods for bone mineral measurement and challenge the comparability of different methods. PMID:10525711

  8. Sensitivity of linear CCD array based film scanners used for film dosimetry

    SciTech Connect

    Devic, Slobodan; Wang Yizhen; Tomic, Nada; Podgorsak, Ervin B.

    2006-11-15

    Film dosimetry is commonly performed by using linear CCD array transmission optical densitometers. However, these devices suffer from a variation in response along the detector array. If not properly corrected for, this nonuniformity may lead to significant overestimations of the measured dose as one approaches regions close to the edges of the scanning region. In this note, we present measurements of the spatial response of an AGFA Arcus II document scanner used for radiochromic film dosimetry. Results and methods presented in this work can be generalized to other CCD based transmission scanners used for film dosimetry employing either radiochromic or radiographic films.

  9. Dye fading test for mission control operator console displays

    NASA Technical Reports Server (NTRS)

    Lockwood, H. E.

    1975-01-01

    A dye fading test of 40 days duration was conducted to determine the effect of mission control operator console and ambient lighting effects on a series of photographic products under consideration for use in mission console operator consoles. Six different display samples, each containing 36 windows of several different colors, were prepared and placed in the mission control consoles for testing. No significant changes were recorded during the testing period. All changes were attributed to a mechanical problem with the densitometer. Detailed results are given in graphs.

  10. The use of infrared absorption to determine density of liquid hydrogen.

    NASA Technical Reports Server (NTRS)

    Unland, H. D.; Timmerhaus, K. D.; Kropschot, R. H.

    1972-01-01

    Experimental evaluation of the use of infrared absorption for determining the density of liquid hydrogen, and discussion of the feasibility of an airborne densitometer based on this concept. The results indicate that infrared absorption of liquid hydrogen is highly sensitive to the density of hydrogen, and, under the operating limitations of the equipment and experimental techniques used, the determined values proved to be repeatable to an accuracy of 2.7%. The desiderata and limitations of an in-flight density-determining device are outlined, and some of the feasibility problems are defined.

  11. Lessons Learned In Developing The VACIS™ Products

    NASA Astrophysics Data System (ADS)

    Orphan, Victor J.

    2011-06-01

    SAIC's development of VACIS™ provides useful "lessons learned" in bridging the gap from an idea to a security or contraband detection product. From a gamma densitometer idea for solving a specific Customs Service (CS) requirement (detection of drugs in near-empty tanker trucks) in mid-1990's, SAIC developed a broad line of vehicle and cargo inspections systems (over 500 systems deployed to date) based on a gamma-ray radiographic imaging technique. This paper analyzes the reasons for the successful development of VACIS and attempts to identify "lessons learned" useful for future security and contraband detection product developments.

  12. Effect of sun elevation upon remote sensing of ocean color over an acid waste dump site

    NASA Technical Reports Server (NTRS)

    Bressette, W. E.

    1978-01-01

    Photographic flights were made over an ocean acid waste dump site while dumping was in progress. The flights resulted in wide angle, broadband, spectral radiance film exposure data between the wavelengths of 500 to 900 nanometers for sun elevation angles ranging from 26 to 42 degrees. It is shown from densitometer data that the spectral signature of acid waste discharged into ocean water can be observed photographically, the influence of sun elevation upon remotely sensed apparent color can be normalized by using a single spectral band ratioing technique, and photographic quantification and mapping of acid waste through its suspended iron precipitate appears possible.

  13. Lessons Learned In Developing The VACIS Products

    SciTech Connect

    Orphan, Victor J.

    2011-06-01

    SAIC's development of VACIS provides useful 'lessons learned' in bridging the gap from an idea to a security or contraband detection product. From a gamma densitometer idea for solving a specific Customs Service (CS) requirement (detection of drugs in near-empty tanker trucks) in mid-1990's, SAIC developed a broad line of vehicle and cargo inspections systems (over 500 systems deployed to date) based on a gamma-ray radiographic imaging technique. This paper analyzes the reasons for the successful development of VACIS and attempts to identify ''lessons learned'' useful for future security and contraband detection product developments.

  14. Applications of densitometry in remote sensing learning experiences

    NASA Technical Reports Server (NTRS)

    Lind, A.

    1981-01-01

    Information on the use of densitometry in remote sensing courses is provided. The use of a densitometer provides the student with a type of hands on experience in which direct manipulation of image products is involved, and the procedures are easily and quickly learned facilitating the collection and analysis of quantitative data on the radiometric properties of aerial photographs and satellite images. These data can then be used for examining relationships between image tones or colors and ground conditions. Suggestions regarding the selection of equipment and imagery are made.

  15. Sensitivity of linear CCD array based film scanners used for film dosimetry.

    PubMed

    Devic, Slobodan; Wang, Yi-Zhen; Tomic, Nada; Podgorsak, Ervin B

    2006-11-01

    Film dosimetry is commonly performed by using linear CCD array transmission optical densitometers. However, these devices suffer from a variation in response along the detector array. If not properly corrected for, this nonuniformity may lead to significant overestimations of the measured dose as one approaches regions close to the edges of the scanning region. In this note, we present measurements of the spatial response of an AGFA Arcus II document scanner used for radiochromic film dosimetry. Results and methods presented in this work can be generalized to other CCD based transmission scanners used for film dosimetry employing either radiochromic or radiographic films. PMID:17153378

  16. Two-phase flow measurements with advanced instrumented spool pieces

    SciTech Connect

    Turnage, K.C.

    1980-09-01

    A series of two-phase, air-water and steam-water tests performed with instrumented piping spool pieces is described. The behavior of the three-beam densitometer, turbine meter, and drag flowmeter is discussed in terms of two-phase models. Results from application of some two-phase mass flow models to the recorded spool piece data are shown. Results of the study are used to make recommendations regarding spool piece design, instrument selection, and data reduction methods to obtain more accurate measurements of two-phase flow parameters. 13 refs., 23 figs., 1 tab.

  17. Annular flow of R-134a through a high aspect ratio duct: Local void fraction, droplet velocity and droplet size measurements

    SciTech Connect

    Trabold, T.A.; Kumar, R.; Vassallo, P.F.

    1998-11-01

    Local measurements were made in annular flow of R-134a through a vertical duct. Using a gamma densitometer, hot-film anemometer and laser Doppler velocimeter, profiles of void fraction, liquid droplet frequency and droplet velocity were acquired across the narrow test section dimension. Based upon these results, data for liquid droplet size were obtained and compared to previous experimental results from the literature. These data are useful for developing an improved understanding of practical two-phase refrigerant flows, and for assessment of advanced two-fluid computer codes.

  18. High spatial resolution photographs of the sun in L alpha radiation.

    NASA Technical Reports Server (NTRS)

    Prinz, D. K.

    1973-01-01

    Photographs of the sun in predominantly L alpha radiation (centered at 1215.67 A) with 3-sec spatial resolution were taken from an Aerobee rocket shortly after fourth contact by the moon on the eclipse day of July 10, 1972. This preliminary reporting of the results describes the instrument and shows two of the photographs taken. The supergranulation is manifest, and active regions and filaments are well resolved over the entire disk. Densitometer traces across the disk are presented, giving the flux incident on the earth from active regions, cell boundaries, and filaments.

  19. [Ultrasound densitometry of the heel bone in the diagnosis of osseous tissue metabolic abnormalities in patients with rheumatoid arthritis].

    PubMed

    Iakimenko, E A; Dets', V V; Tbileli, V V

    2001-01-01

    The implication was studied of such factors as occurrence of the affliction, sex, inflammation activity, joint functional inadequacies, intake of steroids in the development of osteopenia and osteoporosis in patients with rheumatoid arthritis (RA). Determined in the above patients were RRF, SOS, BUA with the aid of the ultrasonic densitometer UBIS 5000 of the DMS (FRANCIUM) firm. Of the 42 examined patients, osteoporosis was identified in 28.5 percent, osteopenia in 45.3 percent of cases, the degree associated with RA duration, inflammation activity, function disorders of the joints favored by intensification of processes of osteal resorption in rheumatoid arthritis. PMID:11881371

  20. Method of high-precision microsampled blood and plasma mass densitometry

    NASA Technical Reports Server (NTRS)

    Hinghofer-Szalkay, H.

    1986-01-01

    The reliability of the mechanical oscillator technique for blood and plasma density measurements on samples of volumes less than 0.1 ml is examined, and a precision of 0.001 g/l is found if plasma-isodensic heparin solution and siliconized densitometers are employed. Sources of measurement errors in the density determinations include storage of plasma samples, inhomogeneity of blood samples, and density reading before adequate temperature equilibration. In tests of plasma sample storage, the best reproducibility was obtained with samples kept at 4 C. Linear correlations were found between plasma density and plasma protein concentration, blood density and blood hemoglobin concentration, and erythrocyte density and MCHC.

  1. Moon Technology For A New Artform

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The keystone of the density slicing process is an instrument called a densitometer, which can "see" many subtle gradations not visible to the human eye. This instrument was integrated into a computerized system which analyzed the tonal density of a moon photo, assigned a color code to each of the various shades, and created on a video monitor a new picture in which each color represented a particular measurement, such as height or depth. Density slicing, applied to telescopic photos and later to close-up views acquired by unmanned spacecraft, provided the foundation for NASA's extensive study and selection of safe Apollo landing sites.

  2. Measurement of two-component flow using ultrasonic flowmeters

    NASA Astrophysics Data System (ADS)

    Whitehouse, J. C.; Eghbali, D. A.; Flitton, V. E.; Anderson, D. G.

    Calibration of transit-time and Doppler ultrasonic flowmeters under two-component flow conditions has been conducted on 400 mm (16-in.) pipe. Testing covered total flows of 0.19 to 1.89 m(exp 3)/s (3000 to 30,000 gpm) and void fractions up to 40 percent. Both flowmeter types accurately measured total volumetric flow over a portion of their ranges. Pipe average void fraction, based on a three-beam gamma densitometer, was used to determine water component flow under stratified flow conditions, with similar results.

  3. Slurry-based fabrication of chopped fiberglass composite preforms

    SciTech Connect

    Moore, G.A.; Johnson, R.W.; Landon, M.D.; Stoots, C.M.; Anderson, J.L.

    1995-12-01

    A water-based process for the fabrication of chopped fiberglass preforms is being developed in collaboration with the Automotive Composite Consortium (ACC) and The Budd Company. This slurry process uses hydraulic pressure to form highly compacted fiberglass preforms on contoured, perforated metal screens. The preforms will be used in the development of structural automotive composites. A key objective is to produce preforms having uniform areal density. Computational simulation of variable open area screens, and areal density mapping using a gamma densitometer are discussed.

  4. Simulation of Hanford Tank 241-C-106 Waste Release into Tank 241-Y-102

    SciTech Connect

    KP Recknagle; Y Onishi

    1999-05-19

    Waste stored in Hdord single-shell Tank 241-C-106 will be sluiced with a supernatant liquid from doubIe-shell Tank 241 -AY- 102 (AY-1 02) at the U.S. Department of Energy's Har@ord Site in Eastern Washington. The resulting slurry, containing up to 30 wtYo solids, will then be transferred to Tank AY-102. During the sluicing process, it is important to know the mass of the solids being transferred into AY- 102. One of the primary instruments used to measure solids transfer is an E+ densitometer located near the periphery of the tank at riser 15S. This study was undert.dcen to assess how well a densitometer measurement could represent the total mass of soiids transferred if a uniform lateral distribution was assumed. The study evaluated the C-1 06 slurry mixing and accumulation in Tank AY- 102 for the following five cases: Case 1: 3 wt'%0 slurry in 6.4-m AY-102 waste Case 2: 3 w-t% slurry in 4.3-m AY-102 waste Case 3: 30 wtYo slurry in 6.4-m AY-102 waste Case 4: 30 wt% slurry in 4.3-m AY-102 waste Case 5: 30 wt% slurry in 5. O-m AY-102 waste. The tirne-dependent, three-dimensional, TEMPEST computer code was used to simulate solid deposition and accumulation during the injection of the C-106 slurry into AY-102 through four injection nozzles. The TEMPEST computer code was applied previously to other Hanford tanks, AP-102, SY-102, AZ-101, SY-101, AY-102, and C-106, to model tank waste mixing with rotating pump jets, gas rollover events, waste transfer from one tank to another, and pump-out retrieval of the sluiced waste. The model results indicate that the solid depth accumulated at the densitometer is within 5% of the average depth accumulation. Thus the reading of the densitometer is expected to represent the total mass of the transferred solids reasonably well.

  5. Evaluation of a new biochemical index for the estimation of bone demineralization using artificial intelligence.

    PubMed

    Barnhill, S D; Zhang, Z; Madyastha, K R

    1995-04-01

    The use of artificial neural networks (ANN) for the identification of a positive correlation between the QuiOs quotient, a single-valued indicator of bone mineral density, and multisite dual energy x-ray absorptiometry (DEXA) measurements is described. The measurements were obtained using the Hologic QDRR-2000 x-ray bone densitometer in a multicenter clinical trial including 374 female patients. The QuiOs quotient estimates bone mineral density and determines the severity of bone density loss. This quotient is calculated by using a proprietary software program to perform a multivariate analysis of the results of testing of serum levels of calcium, phosphate, total alkaline phosphate, two alkaline phosphatase isoenzymes (liver and intestine), estradiol, and progesterone. The results show that given the four DEXA measurements obtained from the bone densitometer, the trained neural network can predict whether the corresponding QuiOs score of the same patient will be below the cutoff score of 0.690. The findings in this study indicate a positive correlation between DEXA measurements and the QuiOs quotient obtained from two different sources. PMID:10150355

  6. Combining 3D optical imaging and dual energy absorptiometry to measure three compositional components

    NASA Astrophysics Data System (ADS)

    Malkov, Serghei; Shepherd, John

    2014-02-01

    We report on the design of the technique combining 3D optical imaging and dual-energy absorptiometry body scanning to estimate local body area compositions of three compartments. Dual-energy attenuation and body shape measures are used together to solve for the three compositional tissue thicknesses: water, lipid, and protein. We designed phantoms with tissue-like properties as our reference standards for calibration purposes. The calibration was created by fitting phantom values using non-linear regression of quadratic and truncated polynomials. Dual-energy measurements were performed on tissue-mimicking phantoms using a bone densitometer unit. The phantoms were made of materials shown to have similar x-ray attenuation properties of the biological compositional compartments. The components for the solid phantom were tested and their high energy/low energy attenuation ratios are in good correspondent to water, lipid, and protein for the densitometer x-ray region. The three-dimensional body shape was reconstructed from the depth maps generated by Microsoft Kinect for Windows. We used open-source Point Cloud Library and freeware software to produce dense point clouds. Accuracy and precision of compositional and thickness measures were calculated. The error contributions due to two modalities were estimated. The preliminary phantom composition and shape measurements are found to demonstrate the feasibility of the method proposed.

  7. Combining 3D optical imaging and dual energy absorptiometry to measure three compositional components

    PubMed Central

    Malkov, Serghei; Shepherd, John

    2014-01-01

    We report on the design of the technique combining 3D optical imaging and dual-energy absorptiometry body scanning to estimate local body area compositions of three compartments. Dual-energy attenuation and body shape measures are used together to solve for the three compositional tissue thicknesses: water, lipid, and protein. We designed phantoms with tissue-like properties as our reference standards for calibration purposes. The calibration was created by fitting phantom values using non-linear regression of quadratic and truncated polynomials. Dual-energy measurements were performed on tissue-mimicking phantoms using a bone densitometer unit. The phantoms were made of materials shown to have similar x-ray attenuation properties of the biological compositional compartments. The components for the solid phantom were tested and their high energy/low energy attenuation ratios are in good correspondent to water, lipid, and protein for the densitometer x-ray region. The three-dimensional body shape was reconstructed from the depth maps generated by Microsoft Kinect for Windows. We used open-source Point Cloud Library and freeware software to produce dense point clouds. Accuracy and precision of compositional and thickness measures were calculated. The error contributions due to two modalities were estimated. The preliminary phantom composition and shape measurements are found to demonstrate the feasibility of the method proposed. PMID:25083118

  8. Investigation of using bone texture analysis on bone densitometry images

    NASA Astrophysics Data System (ADS)

    Chinander, Michael R.; Giger, Maryellen L.; Shah, Ruchi D.; Vokes, Tamara

    2002-05-01

    We previously developed bone texture analysis methods to assess bone strength on digitized radiographs. Here, we compare the analyses performed on digitized screen-film to those obtained on peripheral bone densitometry images. A leg phantom was imaged with both a PIXI (GE Medical Systems; Milwaukee, WI) bone densitometer (0.200-mm pixel size) and a screen-film system, with the films being subsequently digitized by a laser film digitizer (0.100-mm pixel size). The phantom was radiographically scanned multiple times with the densitometer at the default parameters and for increasing exposure times. Fourier-based texture features were calculated from regions of interest from images from both modalities. The bone densitometry images contained more quantum noise than the radiographs resulting in increased values for the first moment of the power spectrum texture feature (1.22 times higher than from the standard radiograph). Presence of such noise may adversely affect the texture feature's ability to distinguish between strong and weak bone. By either increasing the exposure time or averaging multiple scans in the spatial frequency domain, we showed a reduction in the effect of the quantum mottle on the first moment of the power spectrum.

  9. Measurement of SRS reactor recirculation pump performance using pump motor power

    SciTech Connect

    Whitehouse, J.C.

    1994-03-01

    In order to accurately predict reactor hydraulic behavior during a hypothetical Loss-of-Coolant-Accident (LOCA) the performance of reactor coolant pumps under off-design conditions must be understood. The LOCA of primary interest for the Savannah River Site (SRS) production reactors involves the aspiration of air into the recirculated heavy water flow as reactor tank inventory is lost (system temperatures are too low to result in significant flashing of water coolant into steam). Entrained air causes degradation in the performance of the large recirculation pumps. The amount of degradation is a parameter used in computer codes which predict the course of the accident. This paper describes the analysis of data obtained during in-reactor simulated LOCA tests, and presents the head degradation curve for the SRS reactor recirculation pumps. The greatest challenge of the analysis was to determine a reasonable estimate of mixture density at the pump suction. Specially designed three-beam densitometers were used to determine mixture density. Since it was not feasible to place them in the most advantageous location the measured pump motor power, along with other techniques (pressure corrected gamma densitometer void fraction), were used to calculate the average mixture density at the pump impeller. These techniques provided good estimates of pump suction mixture density. Measurements from more conventional instruments were used to arrive at the value of pump two-component head over a wide range of flows. The results were significantly different from previous work with commercial reactor recirculation pumps.

  10. Use of color, color infrared, black and white films, and video systems in detecting health, stress, and disease in vegetation

    NASA Astrophysics Data System (ADS)

    Blazquez, Carlos H.

    1991-02-01

    Ground and aerial experiments were conducted with color (NC) color infrared (CIR) and black and white film and video systems to compare the limitations! advantages of each method of image acquisition with photographs of natural vegetation including cypress stands wetlands and cultivated crops such as: tomatoes cucumbers and citrus. Image analysis with a Linear Measuring System (LMS) and a scanning densitometer were used to quantify healthy stressed and diseased foliage!canopy of each crop for comparisons with visual estimates. videography and photography were useful in delineating topographic features and location of vegetation. The NC video systems yielded images that distinctly separated healthy and dying foliage but did not compare with the CIR video or photography in outlining distinct areas of stress and disease. Aerial photography provided a synoptic view of the fields and cypress stands not otherwise possible. CIR images were easier to process with the LMS than NC video or photographic frames. CIR video and photographic systems produced clearer differences between healthy and stressed foliage. Spectral curves produced with the scanning densitometer correlated well with visual grading of health and stress. . 2.

  11. Measurement of humerus and radius bone mineral content in the term and preterm infant

    SciTech Connect

    Vyhmeister, N.R.; Linkhart, T.A.

    1988-07-01

    We compared two anatomic sites for single-photon absorptiometric measurement of bone mineral content (BMC) in term and preterm infants. The distal one third of the radius and the midportion of the humerus were evaluated for measurements of BMC with an unmodified, commercially available bone densitometer. We assessed reproducibility of BMC and bone width (BW) measurements and defined normal at-birth ranges of BMC, BW, and BMC/BW ratio for infants with gestational ages of 24 to 42 weeks. Humerus BMC correlated with gestational age, birth weight, and BW of patients and did not differ from humerus BMC values determined over the same range of gestational ages at another center. Representative serial measurements of two very low birth weight (VLBW) infants are presented to demonstrate the feasibility of using humerus BMC in longitudinal studies to assess changes in bone mineralization. We conclude that bone densitometer measurements of mid-humerus BMC can be successfully performed and are preferable to similar measurements of the radius for VLBW infants. Normal humerus BMC values were defined for use in diagnosis and evaluation of the efficacy of treatment in VLBW infants who are at high risk of developing osteopenia of prematurity.

  12. Concentration of rat brown adipose tissue uncoupling protein may not be correlated with /sup 3/H-GDP binding

    SciTech Connect

    Henningfield, M.F.; Swick, A.G.; Swick, R.W.

    1986-03-01

    Rats fed diets low in protein or exposed to cold show an increase in brown adipose tissue (BAT) mitochondrial /sup 3/H-GDP binding. To investigate this phenomenon further, the uncoupling protein associated with BAT function was measured immunochemically on nitrocellulose blots. Quantitation of uncoupling protein was achieved by densitometer scanning with a BioRad densitometer. Peaks were integrated with Chromatochart software and an Apple IIe computer. A standard curve of purified uncoupling protein (50 to 500 ng) was used to calculate uncoupling protein concentration. There is a 1.5-fold increase in uncoupling protein per mg of protein in BAT mitochondria from rats exposed to cold for 15 days. There was no decrease in uncoupling protein from rats exposed to the cold followed by 24 h at 27/sup 0/C although /sup 3/H-GDP binding had decreased by half. Rats fed diets containing either 5 or 15% lactalbumin for 3 weeks did not show differences in uncoupling protein concentration although /sup 3/H-GDP binding was 1.5-fold greater in BAT mitochondria from the low protein group. These results indicate that GDP binding does not necessarily reflect the concentration of uncoupling protein in BAT mitochondria.

  13. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi

    2004-07-31

    We have tested the loop elevation system. We raised the mast to approximately 25 to 30 degrees from horizontal. All went well. However, while lowering the mast, it moved laterally a couple of degrees. Upon visual inspection, severe spalling of the concrete on the face of the support pillar, and deformation of the steel support structure was observed. At this time, the facility is ready for testing in the horizontal position. A new air compressor has been received and set in place for the ACTS test loop. A new laboratory has been built near the ACTS test loop Roughened cups and rotors for the viscometer (RS300) were obtained. Rheologies of aqueous foams were measured using three different cup-rotor assemblies that have different surface roughness. The relationship between surface roughness and foam rheology was investigated. Re-calibration of nuclear densitometers has been finished. The re-calibration was also performed with 1% surfactant foam. A new cuttings injection system was installed at the bottom of the injection tower. It replaced the previous injection auger. A mechanistic model for cuttings transport with aerated mud has been developed. Cuttings transport mechanisms with aerated water at various conditions were experimentally investigated. A total of 39 tests were performed. Comparisons between the model predictions and experimental measurements show a satisfactory agreement. Results from the ultrasonic monitoring system indicated that we could distinguish between different sand levels. We also have devised ways to achieve consistency of performance by securing the sensors in the caps in exactly the same manner as long as the sensors are not removed from the caps. A preliminary test was conducted on the main flow loop at 100 gpm flow rate and 20 lb/min cuttings injection rate. The measured bed thickness using the ultrasonic method showed a satisfactory agreement with nuclear densitometer readings. Thirty different data points were collected after the test

  14. A DXA Whole Body Composition Cross-Calibration Experience: Evaluation With Humans, Spine, and Whole Body Phantoms.

    PubMed

    Krueger, Diane; Libber, Jessie; Sanfilippo, Jennifer; Yu, Hui Jing; Horvath, Blaine; Miller, Colin G; Binkley, Neil

    2016-01-01

    New densitometer installation requires cross-calibration for accurate longitudinal assessment. When replacing a unit with the same model, the International Society for Clinical Densitometry recommends cross-calibrating by scanning phantoms 10 times on each instrument and states that spine bone mineral density (BMD) should be within 1%, whereas total body lean, fat, and %fat mass should be within 2% of the prior instrument. However, there is limited validation that these recommendations provide adequate total body cross-calibration. Here, we report a total body cross-calibration experience with phantoms and humans. Cross-calibration between an existing and new Lunar iDXA was performed using 3 encapsulated spine phantoms (GE [GE Lunar, Madison, WI], BioClinica [BioClinica Inc, Princeton, NJ], and Hologic [Hologic Inc, Bedford, MA]), 1 total body composition phantom (BioClinica), and 30 human volunteers. Thirty scans of each phantom and a total body scan of human volunteers were obtained on each instrument. All spine phantom BMD means were similar (within 1%; <-0.010 g/cm2 bias) between the existing and new dual-energy X-ray absorptiometry unit. The BioClinica body composition phantom (BBCP) BMD and bone mineral content (BMC) values were within 2% with biases of 0.005 g/cm2 and -3.4 g. However, lean and fat mass and %fat differed by 4.6%-7.7% with biases of +463 g, -496 g, and -2.8%, respectively. In vivo comparison supported BBCP data; BMD and BMC were within ∼2%, but lean and fat mass and %fat differed from 1.6% to 4.9% with biases of +833 g, -860 g, and -1.1%. As all body composition comparisons exceeded the recommended 2%, the new densitometer was recalibrated. After recalibration, in vivo bias was lower (<0.05%) for lean and fat; -23 and -5 g, respectively. Similarly, BBCP lean and fat agreement improved. In conclusion, the BBCP behaves similarly, but not identical, to human in vivo measurements for densitometer cross-calibration. Spine phantoms, despite good

  15. Meiotic origin of triploidy in the frog detected by genetic analysis of enzyme polymorphisms.

    PubMed

    Wright, D A; Huang, C P; Chuoke, B D

    1976-10-01

    A female frog heterozygous at two unlinked loci, specifying electrophoretic forms of mannosephosphate isomerase (MPI) and malate dehydrogenase (MDH) was crossed to male frogs homozygous for different alleles at each locus. In the offspring approximately ten percent proved to be triploid according to nucleolar and chromosome counts of tail tip cells. Most of these triploids had both maternal alleles at the MDH and MPI loci suggesting that the first meiotic division was repressed. Others seemed to represent a repressed second meiotic division and one animal, a pentaploid, could only have resulted from inhibition of both meiotic divisions of the egg. Densitometer tracings of starch gels stained for 6 phosphogluconate and isocitrate dehydrogenases, expected to be heterozygous in a particular cross, demonstrated that the triploids had twice as much maternal as paternal gene product for each locus, similar to patterns found in triploids produced by nuclear transplantation. PMID:1087260

  16. California coast nearshore processes study

    NASA Technical Reports Server (NTRS)

    Pirie, D. M.; Steller, D. D. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. This report contains the techniques used for enhancing and analyzing nearshore processes from ERTS-1 and aircraft data. Four California nearshore sites are used as test cells including the San Francisco area, Monterey Bay, Santa Barbara Channel, and Los Angeles area. Techniques used for analyzing the test cells included direct photographic processing, computer compatible tape gain change enhancement, discrete point density analysis and plotting, and densitometer enhancement. Using these methods, it is possible to measure the seaward extent of the suspended sediment transport and to differentiate sediment levels within the individual sediment lobes. The movement of riverine discharged suspensates and coastal sediments by currents was an intricate part of the sediment transport analysis. The larger estuaries in the test cell areas were also studied for flushing characteristics.

  17. Compton scatter with polychromatic sources for lung densitometry.

    PubMed

    Hanson, J A; Moore, W E; Figley, M M; Duke, P R

    1984-01-01

    A mobile lung densitometer using conventional x-ray tubes, NaI detectors, and principles of two-source, two-detector Compton scattered densitometry, is described. The device is capable of one to two per second density measurements from a 45-cm3 volume with a precision of 5%. The expected in vivo accuracy (2%-3%) is determined by using an anthropomorphic phantom with replaceable lung inserts. The unintentional detection of multiple-scattered x rays results in a small density-dependent error. This error is predictable and relatively insensitive to differences in surrounding absorbers such as the chest wall. With this device, dynamic in vivo densitometry of the lung in the clinical laboratory and intensive care unit will be possible. PMID:6503878

  18. Copper iodide staining and determination of proteins adsorbed to microtiter plates.

    PubMed

    Root, D D; Reisler, E

    1990-04-01

    Copper iodide staining and determination of proteins adsorbed to polystyrene microtiter plates are described. The minimum amount of copper iodide-stained protein detected in densitometric measurements is approximately 20 pg/mm2. Enzyme immunoassay readers may also be used for the determination of copper iodide-stained proteins, but are less sensitive than densitometers. The densitometric readings of copper iodide-stained proteins vary linearly with the amount of protein present as verified by enzymatic and radioactive probes. Staining is complete in 2-3 min and may be removed by a 30-min treatment with EDTA without loss of adsorbed protein or immunoreactivity. The exact amount of protein adsorbed to microtiter plate wells can be measured by using protein bound and stained on nitrocellulose as a calibration curve. Copper iodide staining is a rapid, convenient, and inexpensive alternative to radioactive measurements of similar parameters. PMID:1694063

  19. MASFLO: a computer code to calculate mass flow rates in the Thermal-Hydraulic Test Facility (THTF). Technical report

    SciTech Connect

    White, M.D.

    1980-05-01

    This report documents a modular data interpretation computer code. The MASFLO code is a Fortran code used in the Oak Ridge National Laboratory Blowdown Heat Transfer Program to convert measured quantities of density, volumetric flow, and momentum flux into a calculated quantity: mass flow rate. The code performs both homogeneous and two-velocity calculations. The homogeneous models incorporate various combinations of the Thermal-Hydraulic Test Facility instrumented spool piece turbine flow meter, gamma densitometer, and drag disk readings. The two-velocity calculations also incorporate these instruments, but in models developed by Aya, Rouhani, and Popper. Each subroutine is described briefly, and input instructions are provided in the appendix along with a sample of the code output.

  20. Liquid Densities of Fluorinated Ethers

    NASA Astrophysics Data System (ADS)

    Nakazawa, Noriaki; Sako, Takeshi; Nakane, Takashi; Sekiya, Akira; Kawamura, Mitsutaka; Sato, Masahito; Mochizuki, Yuji; Takada, Naoto; Yasumoto, Masahiko

    The liquid densities of thirteen fluorinated ethers which are expected as promising candidates of CFC alternatives were measured at temperatures from 278 K to 323 K and atmospheric pressure. The fluorinated ethers used in this study are 1-difluoromethoxy-1,1, 2- trifluoroethane, 1-methoxy-1, 1,2,2-tetrafluoroethane, 1-methoxy-2,2 ,3 ,3- tetrafluoropropane, 1-methoxy-1-trifluoromethy1-2,2 ,2- trifluoroethane, 1-methoxy-1,1,2,2, 3-hexafluoropropane,1-difluoromethoxy-2,2, 3, 3 -tetrafluoropropane, 1-methoxy-heptafluoropropane,1-difluoromethoxy-2, 2, 3, 3, 3-pentafluoropropane, 1- (2, 2, 2-trifruoroethoxy) -1, 1, 2,2-tetrafluoroethane, 1-pentafluoroethoxy-1, 1, 2, 2-tetrafluoroethane,2-trifluoromethoxy-1, 1, 1,2-tetrafluorobutane, 1-proxynonafluorobutane, and 1-ethoxy-undecafluoropentane. The liquid density has been measured by the vibrating tube densitometer (ANTON PARR, DMA 602) within an error of 0.07%. The liquid densities decrease monotonically with increase of temperature.

  1. Gadolinium concentration analysis in brain phantom by X-ray fluorescence.

    PubMed

    Almalki, Musaed; Majid, Samir Abdul; Butler, Philip H; Reinisch, Lou

    2010-06-01

    We have measured the X-ray fluorescence from gadolinium as a function of concentration and position in tumors of different sizes and shapes in a head phantom. The gadolinium fluorescence was excited with a 36 GBq Am-241 source. The fluorescence signal was detected with a CdTe detector and a multi-channel analyzer. The fluorescence peak was clearly separated from the scattered X-rays. Concentrations of 5.62-78.63 mg/ml of Gd ion were used in 1, 2, and 3 cm diameter spherical tumors and a 2x4 cm oblate spheroid tumor. The data show trends approaching saturation for the highest concentrations, probably due to reabsorption in the tumor. A comparison of X-ray photographic imaging and densitometer measurements to determine concentration is also presented. PMID:20596811

  2. The measurement of capsule heat transfer gaps using neutron radiography.

    NASA Technical Reports Server (NTRS)

    Thaler, L. A.

    1971-01-01

    The use of neutron radiographs to determine dimensional changes of heat transfer gaps in cylindrical nuclear fueled capsules is described. A method was developed which involves scanning a very fine grained neutron radiograph negative with a recording microdensitometer. The output of the densitometer is recorded on graph paper and the heat transfer gap is plotted as a well-defined optical density change. Calibration of the recording microdensitometer ratio arms permits measurements to be made of the heat transfer optical density change from the microdensitometer trace. Total heat transfer gaps, measured by this method, agree with the physical measurements within plus or minus 0.005 cm over a range of gaps from 0.061 to 0.178 cm.

  3. Reference data for ultrasonic bone measurement: variation with age in 2087 Caucasian women aged 16-93 years.

    PubMed

    Truscott, J G

    1997-10-01

    Data from the measurement of broadband ultrasonic attenuation (BUA) and speed of sound (SOS), using the Lunar Achilles ultrasonic densitometer, were collected for Caucasian women from five centres in the United Kingdom (Leeds, London, Nottingham, Lincoln and Sheffield). After correcting for machine variability at each site, the data were combined into a central reference database comprising 2087 women aged 16-93 years. The data are presented in 5-year bands and show a mean fall of 0.36% per year for BUA and 0.08% per year for SOS in the 60 years following the attainment of peak bone mass. This fall in BUA compares with that observed using dual energy X-ray absorptiometry studies of the lumbar spine and femoral neck of 0.32% per year and 0.44% per year, respectively, for the age range 25-65 years. PMID:9404204

  4. Computer synthesis of high resolution electron micrographs

    NASA Technical Reports Server (NTRS)

    Nathan, R.

    1976-01-01

    Specimen damage, spherical aberration, low contrast and noisy sensors combine to prevent direct atomic viewing in a conventional electron microscope. The paper describes two methods for obtaining ultra-high resolution in biological specimens under the electron microscope. The first method assumes the physical limits of the electron objective lens and uses a series of dark field images of biological crystals to obtain direct information on the phases of the Fourier diffraction maxima; this information is used in an appropriate computer to synthesize a large aperture lens for a 1-A resolution. The second method assumes there is sufficient amplitude scatter from images recorded in focus which can be utilized with a sensitive densitometer and computer contrast stretching to yield fine structure image details. Cancer virus characterization is discussed as an illustrative example. Numerous photographs supplement the text.

  5. Thermal indicating paints for ammunition health monitoring

    NASA Astrophysics Data System (ADS)

    Zunino, James L., III; Iqbal, Zafar

    2010-04-01

    Thermochromic semiconductive polymers that change color in response to external stimuli, such as heat and radiation, can be utilized to monitor the temperature range and elapsed time profiles of stored and prepositioned munitions. These polymers are being tailored to create paints and coatings that will alert Army logistic staff of dangerous temperature exposures. Irreversible indication via color change in multiple thermal bands, 145 F - 164 F (63o-73°C), 165 F - 184 F (74° - 84° C) and over 185 F (>85°C) are possible with these thermochromic polymers. The resulting active coating can be visually inspected to determine if safe temperatures were exceeded. More detailed information, including cumulative time of exposure in certain temperature bands through changes in optical chromaticity describing the vividness or dullness of a color, can be assessed using a hand-held optical densitometer.

  6. Influence Of Ambient Light On The "Visual" Sensitometric Properties Of, And Detail Perception On, A Radiograph

    NASA Astrophysics Data System (ADS)

    Bollen, Romain; Vranckx, Jean

    1981-07-01

    Lack of perception at high densities on radiographs and the influence of viewing conditions on it are well known. This lack may be caused by blinding effects, by high visual noise at low light intensities or by a third phenomenon i.e. the dependence of the sensitometric properties of film on viewing conditions, which is analyzed in this paper. Reflection of ambient light by the film mainly lowers dramatically high densities and film contrast at these densities. Sensitometric curves of several films were measured under different viewing conditions by means of a telescopic photometer. The curves also can be deduced from curves measured by a regular densitometer when the optical properties of the film, the ambient light level and the light intensity of the negatoscope are known. The influence of the phenomenon under typical viewing conditions for the Curix MR4-film is demonstrated by means of sensitometric- and perceptibility-curves.

  7. Crop identification and acreage measurement utilizing ERTS imagery

    NASA Technical Reports Server (NTRS)

    Vonsteen, D. H. (Principal Investigator)

    1972-01-01

    There are no author-identified significant results in this report. The microdensitometer will be used to analyze data acquired by ERTS-1 imagery. The classification programs and software packages have been acquired and are being prepared for use with the information as it is received. Photo and digital tapes have been acquired for coverage of virtually 100 percent of the test site areas. These areas are located in South Dakota, Idaho, Missouri, and Kansas. Hass 70mm color infrared, infrared, black and white high altitude aerial photography of the test sites is available. Collection of ground truth for updating the data base has been completed and a computer program written to count the number of fields and give total acres by size group for the segments in each test site. Results are given of data analysis performed on digitized data from densitometer measurements of fields of corn, sugar, beets, and alfalfa in Kansas.

  8. Automatic recognition of bone for x-ray bone densitometry

    NASA Astrophysics Data System (ADS)

    Shepp, Larry A.; Vardi, Y.; Lazewatsky, J.; Libeau, James; Stein, Jay A.

    1991-06-01

    We described a method for automatically identifying and separating pixels representing bone from those representing soft tissue in a dual- energy point-scanned projection radiograph of the abdomen. In order to achieve stable quantitative measurement of projected bone mineral density, a calibration using sample bone in regions containing only soft tissue must be performed. In addition, the projected area of bone must be measured. We show that, using an image with a realistically low noise, the histogram of pixel values exhibits a well-defined peak corresponding to the soft tissue region. A threshold at a fixed multiple of the calibration segment value readily separates bone from soft tissue in a wide variety of patient studies. Our technique, which is employed in the Hologic QDR-1000 Bone Densitometer, is rapid, robust, and significantly simpler than a conventional artificial intelligence approach using edge-detection to define objects and expert systems to recognize them.

  9. NOTE: Use of a blood glucose meter for radiochromic film analysis in blood irradiation

    NASA Astrophysics Data System (ADS)

    Cheung, Tsang; Butson, Martin J.; Yu, Peter K. N.

    2002-10-01

    The use of a diabetic blood glucose meter for radiochromic film dosimetry in blood irradiation using x-ray beams on a medical linear accelerator has been investigated. The glucose meter provides optical density analysis in the visible and infrared region using a reflectance measurement technique. By comparing the 'blood sugar' level output with standard calibration gafchromic films a calibration curve is produced for quantitative analysis. Results show that a reproducible dose to meter output curve can be fitted using a second order polynomial function and that blood irradiation doses in vitro were measured to within 7.9% mean error (as compared to ionization chamber results) using the blood glucose meter. This level of accuracy falls below that measured with a standard densitometer (4.3%) however, results show that the blood glucose meter, which would be available in any haematology department, produces an adequate measure of gafchromic film optical density for blood irradiation dosimetry.

  10. Remote sensing of effects of land-use practices on water quality. [environmental surveys using Landsat satellites

    NASA Technical Reports Server (NTRS)

    Graves, D. H.

    1975-01-01

    Research efforts are presented for the use of remote sensing in environmental surveys in Kentucky. Ground truth parameters were established that represent the vegetative cover of disturbed and undisturbed watersheds in the Cumberland Plateau of eastern Kentucky. Several water quality parameters were monitored of the watersheds utilized in the establishment of ground truth data. The capabilities of multistage-multispectral aerial photography and satellite imagery were evaluated in detecting various land use practices. The use of photographic signatures of known land use areas utilizing manually-operated spot densitometers was studied. The correlation of imagery signature data to water quality data was examined. Potential water quality predictions were developed from forested and nonforested watersheds based upon the above correlations. The cost effectiveness of predicting water quality values was evaluated using multistage and satellite imagery sampling techniques.

  11. Imaging retinal densitometry with a confocal Scanning Laser Ophthalmoscope.

    PubMed

    van Norren, D; van de Kraats, J

    1989-01-01

    We describe a novel use of the Scanning Laser Ophthalmoscope (SLO), viz. as an imaging retinal densitometer. In our SLO a helium-neon or an argon laser beam is moved in a raster pattern over the retina; the reflected light is descanned (confocal SLO) and collected by a photomultiplier. Images of the fundus subtending 22 by 18 deg are displayed on a TV monitor. Single frames taken with 514 nm light were stored in a computer in arrays of 256 by 256 pixels and density differences between dark adapted and bleached images were calculated. With a full bleach density differences of about 0.35 were found in the center of the fovea; at retinal eccentricities of 15-20 deg we found 0.15. After selective bleaching with 633 nm light substantial density differences were only seen in the foveal area. We conclude that the confocal SLO is a very suitable instrument for imaging fundus reflectometry. PMID:2631402

  12. Three-energy gamma-ray absorptiometer (TEGA) for nondestructive assay of plutonium and uranium in solution

    SciTech Connect

    Aparo, M.

    1986-01-01

    An experimental approach for the nondestructive characterization of plutonium and uranium solutions is presented. The technique relies on the transmission of photons of three different properly chosen energies, and allows an independent and simultaneous determination of plutonium and uranium by the different absorption of the two elements in the range of K-edge energies. The performances achievable have been evaluated through measurement of a set of solutions using the hardware of the compact K-edge densitometer. The plutonium and uranium concentrations ranged from 50 to 150 g/l. In this concentration range, the relative precision is below 3.0% for uranium assay and below 6% for plutonium assay. Further improvements of the performances of the technique are discussed. 3 refs., 9 figs., 1 tab.

  13. Recent development of radiation measurement instrument for industrial and medical applications

    NASA Astrophysics Data System (ADS)

    Baba, Sueki; Ohmori, Koichi; Mito, Yoshio; Tanoue, Toshiya; Yano, Shigeki; Tokumori, Kenji; Toyofuku, Fukai; Kanda, Shigenobu

    2001-02-01

    Recently, computer imaging technology has developed very high-quality image and fast processing time. X-rays have been used for many purposes such as medical diagnosis and analyzing the structure of industrial materials. However, as X-rays are hazardous to the human body, it is desirable to reduce its exposed dose to a minimum. For this purpose, it is necessary to use a semiconductor radiation detector with a high efficiency for X-rays. We have developed photon-counting CdTe array detector system for medical and industrial use. The bone densitometer for Dual Energy X-ray Absorptometry (DEXA) has been developed to make diagnosis of osteoporosis, and it is developed to analyze a material element for industrial use. Recently, we have developed a monochromatic X-ray CT using a 256 ch CdTe array detector. We found that the array detector systems are very useful for medical and industrial applications.

  14. Thermal and Electrical Characterization of Alumina Substrate for Microelectronic Applications

    SciTech Connect

    Ahmad, S.; Ibrahim, A.; Alias, R.; Shapee, S. M.; Ambak, Z.; Zakaria, S. Z.; Yahya, M. R.; Mat, A. F. A.

    2010-03-11

    This paper reports the effect of sintering temperature on thermal and electrical properties of alumina material as substrate for microelectronic devices. Alumina materials in the form of green sheet with 1 mm thickness were sintered at 1100 deg. C, 1300 deg. C and 1500 deg. C for about 20 hours using heating and cooling rates of 2 deg. C/min. The densities were measured using densitometer and the microstructures of the samples were analyzed using SEM micrographs. Meanwhile thermal and electrical properties of the samples were measured using flash method and impedance analyzer respectively. It was found that thermal conductivity and thermal diffusivity of the substrate increases as sintering temperature increases. It was found also that the dielectric constant of alumina substrate increases as the sintering temperature increases.

  15. California coast nearshore processes study

    NASA Technical Reports Server (NTRS)

    Pirie, D. M. (Principal Investigator)

    1972-01-01

    The author has identified the following significant results. In the Santa Barbara Channel the effect of the California and the Anacapa Currents are clearly seen in image 1109-18073M. The large triangular shaped lobe of suspended particulate matter that stretches almost to Anacapa Island from the Ventura River area is disrupted approximately midchannel by the east-moving Anacapa Current. In the Point Conception area a lobe of suspended material approximately 20 miles long can be seen moving eastward as a result of the California Current. In the San Francisco Bay area the major results include the detection and delineation of the San Francisco Bay, the location and vector of suspended sediment in the San Francisco Bay, and the ability to differentiate morphologic units within the San Francisco Bay tidelands. Several densitometer line traces seaward of the Golden Gate Bridge on image 1075-18173-4 outline the San Francisco Bay and give evidence of good water penetration.

  16. Full-field optical thickness profilometry of semitransparent thin films with transmission densitometry

    SciTech Connect

    Johnson, Jay; Harris, Tequila

    2010-05-20

    A novel bidirectional thickness profilometer based on transmission densitometry was designed to measure the localized thickness of semitransparent films on a dynamic manufacturing line. The densitometer model shows that, for materials with extinction coefficients between 0.3 and 2.9 D/mm, 100-500 {mu}m measurements can be recorded with less than {+-}5% error at more than 10,000 locations in real time. As a demonstration application, the thickness profiles of 75 mmx100 mm regions of polymer electrolyte membrane (PEM) were determined by converting the optical density of the sample to thickness with the Beer-Lambert law. The PEM extinction coefficient was determined to be 1.4 D/mm, with an average thickness error of 4.7%.

  17. Monitoring the growth or decline of vegetation on mine dumps

    NASA Technical Reports Server (NTRS)

    Gilbertson, B. P. (Principal Investigator)

    1975-01-01

    The author has identified the following signficant results. It was established that particular mine dumps throughout the entire test area can be detected and identified. It was also established that patterns of vegetative growth on the mine dumps can be recognized from a simple visual analysis of photographic images. Because vegetation tends to occur in patches on many mine dumps, it is unsatisfactory to classify complete dumps into categories of percentage vegetative cover. A more desirable approach is to classify the patches of vegetation themselves. The coarse resolution of conventional densitometers restricts the accuracy of this procedure, and consequently a direct analysis of ERTS CCT's is preferred. A set of computer programs was written to perform the data reading and manipulating functions required for basic CCT analysis.

  18. LANDSAT applications to wetlands classification in the upper Mississippi River Valley. Ph.D. Thesis. Final Report

    NASA Technical Reports Server (NTRS)

    Lillesand, T. M.; Werth, L. F. (Principal Investigator)

    1980-01-01

    A 25% improvement in average classification accuracy was realized by processing double-date vs. single-date data. Under the spectrally and spatially complex site conditions characterizing the geographical area used, further improvement in wetland classification accuracy is apparently precluded by the spectral and spatial resolution restrictions of the LANDSAT MSS. Full scene analysis of scanning densitometer data extracted from scale infrared photography failed to permit discrimination of many wetland and nonwetland cover types. When classification of photographic data was limited to wetland areas only, much more detailed and accurate classification could be made. The integration of conventional image interpretation (to simply delineate wetland boundaries) and machine assisted classification (to discriminate among cover types present within the wetland areas) appears to warrant further research to study the feasibility and cost of extending this methodology over a large area using LANDSAT and/or small scale photography.

  19. Seasonal variation of IgE and IgG antibody of some atopic patients against the pollen grains of selected plant species.

    PubMed

    Ruffin, J; Shaw, S; Banerjee, S

    1990-01-01

    Several steps were taken to determine the seasonal variation of IgE and IgG antibody against Short Ragweed, Timothy Grass, Tag Alder and White Ash. Extracts of the above pollen grains were separated into their allergen components using SDS-gel electrophoresis and transblotted to nitrocellulose membrane (Western blotting) and probed with sera from atopic patients in every month (August 1987-July 1988). The IgE and IgG antibody against the specific-allergens were detected by double antibody immunoenzyme assay. The percentage of binding was determined by using a 620 video-densitometer. Results indicate that there was no reasonable IgE antibody before the pollination season, but IgEAb appeared after the season and was detectable for several months. Negligible amounts of IgGAb were observed. PMID:2292188

  20. [Salmon calcitonin nasal spray and calcium sandoz forte in the prevention and treatment of osteoporotic fractures in postmenopausal women (information on clinical trial).].

    PubMed

    Vojtassák, J; Makai, F; Rausová, K; Vojtek, R; Svec, A; Sefranková, A

    1994-01-01

    At the First Orthopaedic Clinic in Bratislava, Hlboká 7, since August 24, 1992 a clinical trial is under way which is focused on the effectiveness of treatment with salmon Calcitonin (Miacalcic Sandoz) and calcium (Sandoz) in postmenopausal osteoporosis. On the above mentioned day Sandoz Co. supplied the Clinic with a densitometer Lunar DPX-L working on the principle of double X-ray absorptiometry. The preparation for this clinical trial started at the beginning of 1992. By the end of June in the trial 62 female patients were included. The authors plan to include another 36 patients were included. The authors plan to include another 36 patients by the end of the year, thus the total number should be 100. Key words: osteoporosis, bone densitometry. PMID:20444350

  1. The use of near-infrared photography for biodegradable pollution monitoring of tidal rivers

    NASA Technical Reports Server (NTRS)

    Bressette, W. E.; Lear, D. E., Jr.

    1973-01-01

    On October 2, 1972, a pattern of chlorophyll a containing phytoplankton (algae) was detected from 3-km altitude in a series of near-infrared photographs of the Potomac River 'Salt Wedge Area.' Densitometer traces over the film images, related to in situ measurements of chlorophyll a concentrations that varied from 4 to more than 3000 micrograms/liter, revealed a phytoplankton 'bloom' threshold in the near infrared between the concentration of 34 and 51 micrograms/liter. The photography also revealed bottom features through two meters of water and made it possible to integrate chlorophyll a concentrations over a 16 sq km area to demonstrate this remote sensing technique for biodegradable pollution monitoring.

  2. Important considerations for radiochromic film dosimetry with flatbed CCD scanners and EBT GAFCHROMIC[reg] film

    SciTech Connect

    Lynch, Bart D.; Kozelka, Jakub; Ranade, Manisha K.; Li, Jonathan G.; Simon, William E.; Dempsey, James F.

    2006-12-15

    In this study, we present three significant artifacts that have the potential to negatively impact the accuracy and precision of film dosimetry measurements made using GAFCHROMIC[reg] EBT radiochromic film when read out with CCD flatbed scanners. Films were scanned using three commonly employed instruments: a Macbeth TD932 spot densitometer, an Epson Expression 1680 CCD array scanner, and a Microtek ScanMaker i900 CCD array scanner. For the two scanners we assessed the variation in optical density (OD) of GAFCHROMIC EBT film with scanning bed position, angular rotation of the film with respect to the scan line direction, and temperature inside the scanner due to repeated scanning. Scanning uniform radiochromic films demonstrated a distinct bowing effect in profiles in the direction of the CCD array with a nonuniformity of up to 17%. Profiles along a direction orthogonal to the CCD array demonstrated a 7% variation. A strong angular dependence was found in measurements made with the flatbed scanners; the effect could not be reproduced with the spot densitometer. An IMRT quality assurance film was scanned twice rotating the film 90 deg. between the scans. For films scanned on the Epson scanner, up to 12% variation was observed in unirradiated EBT films rotated between 0 deg. and 90 deg. , which decreased to approximately 8% for EBT films irradiated to 300 cGy. Variations of up to 80% were observed for films scanned with the Microtek scanner. The scanners were found to significantly increase the film temperature with repeated scanning. Film temperature between 18 and 33 deg. C caused OD changes of approximately 7%. Considering these effects, we recommend adherence to a strict scanning protocol that includes: maintaining the orientation of films scanned on flatbed scanners, limiting scanning to the central portion of the scanner bed, and limiting the number of consecutive scans to minimize changes in OD caused by film heating.

  3. The curvature of sensitometric curves for Kodak XV-2 film irradiated with photon and electron beams

    SciTech Connect

    Battum, L. J. van; Huizenga, H.

    2006-07-15

    Sensitometric curves of Kodak XV-2 film, obtained in a time period of ten years with various types of equipment, have been analyzed both for photon and electron beams. The sensitometric slope in the dataset varies more than a factor of 2, which is attributed mainly to variations in developer conditions. In the literature, the single hit equation has been proposed as a model for the sensitometric curve, as with the parameters of the sensitivity and maximum optical density. In this work, the single hit equation has been translated into a polynomial like function as with the parameters of the sensitometric slope and curvature. The model has been applied to fit the sensitometric data. If the dataset is fitted for each single sensitometric curve separately, a large variation is observed for both fit parameters. When sensitometric curves are fitted simultaneously it appears that all curves can be fitted adequately with a sensitometric curvature that is related to the sensitometric slope. When fitting each curve separately, apparently measurement uncertainty hides this relation. This relation appears to be dependent only on the type of densitometer used. No significant differences between beam energies or beam modalities are observed. Using the intrinsic relation between slope and curvature in fitting sensitometric data, e.g., for pretreatment verification of intensity-modulated radiotherapy, will increase the accuracy of the sensitometric curve. A calibration at a single dose point, together with a predetermined densitometer-dependent parameter OD{sub max} will be adequate to find the actual relation between optical density and dose.

  4. Precision feeding can significantly reduce lysine intake and nitrogen excretion without compromising the performance of growing pigs.

    PubMed

    Andretta, I; Pomar, C; Rivest, J; Pomar, J; Radünz, J

    2016-07-01

    This study was developed to assess the impact on performance, nutrient balance, serum parameters and feeding costs resulting from the switching of conventional to precision-feeding programs for growing-finishing pigs. A total of 70 pigs (30.4±2.2 kg BW) were used in a performance trial (84 days). The five treatments used in this experiment were a three-phase group-feeding program (control) obtained with fixed blending proportions of feeds A (high nutrient density) and B (low nutrient density); against four individual daily-phase feeding programs in which the blending proportions of feeds A and B were updated daily to meet 110%, 100%, 90% or 80% of the lysine requirements estimated using a mathematical model. Feed intake was recorded automatically by a computerized device in the feeders, and the pigs were weighed weekly during the project. Body composition traits were estimated by scanning with an ultrasound device and densitometer every 28 days. Nitrogen and phosphorus excretions were calculated by the difference between retention (obtained from densitometer measurements) and intake. Feeding costs were assessed using 2013 ingredient cost data. Feed intake, feed efficiency, back fat thickness, body fat mass and serum contents of total protein and phosphorus were similar among treatments. Feeding pigs in a daily-basis program providing 110%, 100% or 90% of the estimated individual lysine requirements also did not influence BW, body protein mass, weight gain and nitrogen retention in comparison with the animals in the group-feeding program. However, feeding pigs individually with diets tailored to match 100% of nutrient requirements made it possible to reduce (P<0.05) digestible lysine intake by 26%, estimated nitrogen excretion by 30% and feeding costs by US$7.60/pig (-10%) relative to group feeding. Precision feeding is an effective approach to make pig production more sustainable without compromising growth performance. PMID:26759074

  5. Proving Coriolis flowmeters

    SciTech Connect

    Apple, C.

    1995-12-01

    Coriolis meters provide significant advantages for custody transfer measurement of fluids. The most obvious feature is the Coriolis meter`s ability to provide a direct mass flow measurement. This makes Coriolis meters ideally suited to measuring products which are commonly accounted for on a mass basis, such as LPG, NGL, ethylene, liquid CO{sub 2}. Using a single Coriolis meter simplifies the metering system by replacing a volumetric flowmeter, densitometer, and flow computer, with a single measurement device. Another unique feature of Coriolis meters is their ability to measure fluid density independently of mass flow rate. The density measurement is determined in the same manner as any vibrating tube densitometer. By measuring both the mass flow rate ({center_dot}m) and density ({rho}), the Coriolis meter can provide a volumetric flow measurement (q) by performing the following calculation: q = {center_dot}m / {rho}. Coriolis meters have no rotating parts such as bearings or gears, that wear with time. This reduces maintenance costs. Since solids can flow through the meters without damage, strainers are generally unnecessary. Also, gas or vapor in the process fluid which can damage turbine meters due to overspin, will not harm Coriolis meters. The measurement accuracy of Coriolis meters, {+-}0.15%, is suitable for custody transfer measurement. The meters are capable of measuring flow bi-directionally. This is particularly advantageous for loading rack and cavern storage applications. Flowmeters which are used for custody transfer measurement, generally require some means to prove meter accuracy. The principles of operation of Coriolis meters are fundamentally different than those of turbine or positive displacement meters. In order to properly prove these meters it is important to understand some basics about the meters operation and output signals.

  6. Initial characterization of a gel patch dosimeter for in vivo dosimetry

    NASA Astrophysics Data System (ADS)

    Matrosic, C.; Culberson, W.; Rosen, B.; Madsen, E.; Frank, G.; Bednarz, B.

    2016-05-01

    In vivo dosimetry is a greatly underutilized tool for patient safety in clinical external beam radiotherapy treatments, despite being recommended by several national and international organizations (AAPM, ICRU, IAEA, NACP). The reasons for this underutilization mostly relate to the feasibility and cost of in vivo dosimetry methods. Due to the increase in the number of beam angles and dose per fraction in modern treatments, there is a compelling need for a novel dosimeter that is robust and affordable while able to operate properly in these complex conditions. This work presents a gel patch dosimeter as a novel method of in vivo dosimetry. DEFGEL, a 6% T normoxic polyacrylamide gel, was injected into 1 cm thick acrylic molds to create 1 cm thick small cylindrical patch dosimeters. To evaluate the change in optical density due to radiation induced polymerization, dosimeters were scanned before and after irradiation using an in-house developed laser densitometer. The dose–responses of three separate batches of gel were evaluated and compared to check for linearity and repeatability. The response development time was evaluated to ensure that the patch dosimeter could be high throughput. Additionally, the potential of this system to be used as an in vivo dosimeter was tested with a clinically relevant end-to-end in vivo phantom test. All irradiations were performed with a Varian Clinac 21EX at the University of Wisconsin Medical Radiation Research Center (UWMRRC). The dose–response of all three batches of gel was found to be linear within the range of 2–20 Gy. At doses below 0.5 Gy the statistical uncertainties were prohibitively large to make quantitative assessments of the results. The three batches demonstrated good repeatability in the range of 2 Gy to up to 10 Gy, with only slight variations in response at higher doses. For low doses the dosimeter fully developed within an hour while at higher doses they fully developed within four hours. During the in

  7. Initial characterization of a gel patch dosimeter for in vivo dosimetry.

    PubMed

    Matrosic, C; Culberson, W; Rosen, B; Madsen, E; Frank, G; Bednarz, B

    2016-05-21

    In vivo dosimetry is a greatly underutilized tool for patient safety in clinical external beam radiotherapy treatments, despite being recommended by several national and international organizations (AAPM, ICRU, IAEA, NACP). The reasons for this underutilization mostly relate to the feasibility and cost of in vivo dosimetry methods. Due to the increase in the number of beam angles and dose per fraction in modern treatments, there is a compelling need for a novel dosimeter that is robust and affordable while able to operate properly in these complex conditions. This work presents a gel patch dosimeter as a novel method of in vivo dosimetry. DEFGEL, a 6% T normoxic polyacrylamide gel, was injected into 1 cm thick acrylic molds to create 1 cm thick small cylindrical patch dosimeters. To evaluate the change in optical density due to radiation induced polymerization, dosimeters were scanned before and after irradiation using an in-house developed laser densitometer. The dose-responses of three separate batches of gel were evaluated and compared to check for linearity and repeatability. The response development time was evaluated to ensure that the patch dosimeter could be high throughput. Additionally, the potential of this system to be used as an in vivo dosimeter was tested with a clinically relevant end-to-end in vivo phantom test. All irradiations were performed with a Varian Clinac 21EX at the University of Wisconsin Medical Radiation Research Center (UWMRRC). The dose-response of all three batches of gel was found to be linear within the range of 2-20 Gy. At doses below 0.5 Gy the statistical uncertainties were prohibitively large to make quantitative assessments of the results. The three batches demonstrated good repeatability in the range of 2 Gy to up to 10 Gy, with only slight variations in response at higher doses. For low doses the dosimeter fully developed within an hour while at higher doses they fully developed within four hours. During the in vivo

  8. Initial Characterization of a Gel Patch Dosimeter for In Vivo Dosimetry

    PubMed Central

    Matrosic, C; Culberson, W; Rosen, B; Madsen, E; Frank, G; Bednarz, B

    2016-01-01

    In vivo dosimetry is a greatly underutilized tool for patient safety in clinical external beam radiotherapy treatments, despite being recommended by several national and international organizations (AAPM, ICRU, IAEA, NACP). The reasons for this underutilization mostly relate to the feasibility and cost of in vivo dosimetry methods. Due to the increase in the number of beam angles and dose per fraction in modern treatments, there is a compelling need for a novel dosimeter that is robust and affordable while able to operate properly in these complex conditions. This work presents a gel patch dosimeter as a novel method of in vivo dosimetry. DEFGEL, a 6%T normoxic polyacrylamide gel, was injected into 1-cm thick acrylic molds to create 1-cm thick small cylindrical patch dosimeters. To evaluate the change in optical density due to radiation induced polymerization, dosimeters were scanned before and after irradiation using an in-house developed laser densitometer. The dose-responses of three separate batches of gel were evaluated and compared to check for linearity and repeatability. The response development time was evaluated to ensure that the patch dosimeter could be high throughput. Additionally, the potential of this system to be used as an in vivo dosimeter was tested with a clinically relevant end-to-end in vivo phantom test. All irradiations were performed with a Varian Clinac 21EX at the University of Wisconsin Medical Radiation Research Center (UWMRRC). The dose response of all three batches of gel was found to be linear within the range of 2–20 Gy. At doses below 0.5 Gy the statistical uncertainties were prohibitively large to make quantitative assessments of the results. The three batches demonstrated good repeatability in the range of 2 Gy to up to 10 Gy, with only slight variations in response at higher doses. For low doses the dosimeter fully developed within an hour while at higher doses they fully developed within four hours. During the in vivo

  9. Purchase of a PhosphorImager System for plant biology research. Final progress report, July 1992--July 1994

    SciTech Connect

    Jackson, A.O.

    1993-10-01

    Eight DOE supported plant biologists at the University of California-Berkeley were awarded funds ($163,000) for purchase of a Phosphorlmager System to improve the speed, sensitivity, resolution, and quantitation of radioactive data processing and analysis. These funds were used to purchase a Molecular Dynamics Phosphorlmager System consisting of the phosphorlmager, a densitometer, and high resolution storage phosphor screens that have extremely high trapping and storage capacity for energy emitted from isotopes used for biological research such as {sup 32}P, {sup 14}C, {sup 35}S, and {sup 125}I. Software provided with the package permits analysis of the data in several unique ways that are not currently feasible With other methods for analysis. The University of California has purchased additional computer hardware (A MacIntosh Quadra 800 Computer) and has upgraded an IBM computer Mod6l PS2-486 linked with on-line and on off-line workstations via ethernet systems for analysis of data. Data files can also be converted to a TIFF format suitable for graphic analysis and image production on the MacIntosh computer. The system is providing unique advantages for quantitation of data over extremely wide ranges of isotope levels and provides the ability to analyze and manipulate data over wide ranges of sensitivity not previously available with previously used methods of isotope quantitation.

  10. Screening for osteoporosis among post-menopausal women in community pharmacy

    PubMed Central

    Barris Blundell, Damià; Rodríguez Zarzuelo, Carmen; Sabio Sánchez, Belén; Gutiérrez álvarez, José Luis; Navarro Visa, Elena; Muñoz Valdés, Oscar; Garrido Jiménez, Belén; Gómez, Rocío Sánchez

    Objectives To identify postmenopausal women with risk of osteoporosis through quantitative ultrasound imaging (QUI) and to value the medical intervention after the determination of the bone mineral density (BMD). Methods Cross-sectional descriptive study developed in a community pharmacy. During the month of June of 2005 the community pharmacy enrolled postmenopausal women into the study. Women in treatment with calcium, vitamin D, hormone replacement therapy, estrogen receptor modulators, calcitonin or biphosphonates were considered criteria for exclusion. To all the women that consent to participate, the pharmacist measured BMD with the device Sahara Hologic Ultrasound Bone Densitometer at right calcaneus. Following the World Health Organization, women were classified as osteoporotic if their T-Score was less than -2.5 and as osteopenic if their T-Score ranged between -2.5 and -1.0. Results Of the 100 women screened, 11 (11%) presented risk of osteoporosis and 61 (61%) of osteopenia. The 18.5% postmenopausal women with body mass index lesser than 30 presented risk of osteoporosis and the 63.0% osteopenia. Conclusions The QUI constitutes a useful tool in community pharmacy for the screening of osteoporosis and it supposes a greater integration of the community pharmacy within the health care. PMID:25247006

  11. Characterization of radiochromic film scanning techniques used in short-pulse-laser ion acceleration

    SciTech Connect

    Cowan, Joseph S.; Flippo, Kirk A.; Gaillard, Sandrine A.

    2008-10-15

    Radiochromic film (RCF) is increasingly being used as a detector for proton beams from short-pulse laser-matter interaction experiments using the RCF imaging spectroscope technique. The community has traditionally used inexpensive flatbed scanners to digitize and analyze the data, as opposed to more expensive and time-consuming microdensitometers (MicroDs). Often, the RCF densities in some regions exceed an optical density (OD) of 3. Flatbed scanners are generally limited to a maximum OD of {approx}3. Because of the high exposure density, flatbed scanners may yield data that are not reliable due to light scatter and light diffusion from areas of low density to areas of high density. This happens even when the OD is slightly above 1. We will demonstrate the limitations of using flatbed scanners for this type of radiographic media and characterize them compared to measurements made using a MicroD. A technique for cross characterizing both systems using a diffuse densitometer with a NIST wedge will also be presented.

  12. Measurement of high energy x-ray beam penumbra with Gafchromic trade mark sign EBT radiochromic film

    SciTech Connect

    Cheung Tsang; Butson, Martin J.; Yu, Peter K. N.

    2006-08-15

    High energy x-ray beam penumbra are measured using Gafchromic trade mark sign EBT film. Gafchromic trade mark sign EBT, due to its limited energy dependence and high spatial resolution provide a high level of accuracy for dose assessment in penumbral regions. The spatial resolution of film detector systems is normally limited by the scanning resolution of the densitometer. Penumbral widths (80%/20%) measured at D{sub max} were found to be 2.8, 3.0, 3.2, and 3.4 mm ({+-}0.2 mm) using 5, 10, 20, and 30 cm square field sizes, respectively, for a 6 MV linear accelerator produced x-ray beam. This is compared to 3.2 mm{+-}0.2 mm (Kodak EDR2) and 3.6 mm{+-}0.2 mm (Kodak X-Omat V) at 10 cmx10 cm measured using radiographic film. Using a zero volume extrapolation technique for ionization chamber measurements, the 10 cmx10 cm field penumbra at D{sub max} was measured to be 3.1 mm, a close match to Gafchromic trade mark sign EBT results. Penumbral measurements can also be made at other depths, including the surface, as the film does not suffer significantly from dosimetric variations caused by changing x-ray energy spectra. Gafchromic trade mark sign EBT film provides an adequate measure of penumbral dose for high energy x-ray beams.

  13. [Synthesis and characterization of mixed metal oxide pigments].

    PubMed

    Ding, Jie; Yue, Shi-juan; Liu, Cui-ge; Wei, Yong-ju; Meng, Tao; Jiang, Han-jie; Shi, Yong-zheng; Xu, Yi-zhuang; Yu, Jiang; Wu, Jin-guang

    2012-03-01

    In the present work, aluminum chloride and various soluble salts of doping ions were dissolved in water. In addition, urea and polyvinyl pyrrolidone (PVP) were also dissolved in the above aqueous solution under supersonic treatments. Then the solutions were heated to induce the hydrolysis of urea so that soluble aluminum and doping ions convert into insoluble hydroxide or carbonate gels. After calcinations, the obtained gels change to mixed metal oxide pigments whose color is related to type and concentrations of the doping ions. XRD characterization demonstrates that the diffraction patterns of the products are the same as that of alpha-alumina. Diffuse reflectance spectra of samples of the samples in UV-Vis regions show that the absorption bands for d-d transitions of the doping ions undergo considerable change as the coordinate environments change. In addition, L*, a* and b* values of the pigments were measured by using UV-Vis densitometer. SEM results indicate that the size of the pigment powders is in the range 200-300 nm. The pigments are quite stable since no evidence of dissolution was observed after the synthesized pigment is soaked for 24 hours. ICP test shows that very little amount of doped metal occurs in the corresponding filtrate. The above results suggest that these new kinds of mixed metal oxide pigments are stable, non-toxic, environmental friendly and they may be applicable in molten spinning process and provide a new chance for non-aqueous printing and dyeing industry. PMID:22582641

  14. Oxidative stress as a risk factor for osteoporosis in elderly Mexicans as characterized by antioxidant enzymes

    PubMed Central

    Sánchez-Rodríguez, Martha A; Ruiz-Ramos, Mirna; Correa-Muñoz, Elsa; Mendoza-Núñez, Víctor Manuel

    2007-01-01

    Background Oxidative stress (OxS) has recently been linked with osteoporosis; however, we do not know the influence of OxS as an independent risk factor for this disease. Methods We conducted a case-control study in 94 subjects ≥60 years of age, 50 healthy and 44 with osteoporosis. We measured total antioxidant status, plasma lipid peroxides, antioxidant activity of superoxide dismutase and glutathione peroxidase (GPx), and calculated the SOD/GPx ratio. Bone mineral density was obtained at the peripheral DXA in calcaneus using a portable Norland Apollo Densitometer®. Osteoporosis was considered when subjects had a BMD of 2.5 standard deviations or more below the mean value for young adults. Results GPx antioxidant activity was significantly lower in the group of subjects with osteoporosis in comparison with the group of healthy subjects (p < 0.01); in addition, the SOD/GPx ratio was significantly higher in the group of individuals with osteoporosis (p < 0.05). In logistic regression analysis, we found OxS to be an independent risk factor for osteoporosis (odds ratio [OR] = 2.79; 95% confidence interval [95% CI] = 1.08–7.23; p = 0.034). Conclusion Our findings suggest that OxS is an independent risk factor for osteoporosis linked to increase of SOD/GPx ratio. PMID:18088440

  15. Radiopacity Measurement of Restorative Resins Using Film and Three Digital Systems for Comparison with ISO 4049: International Standard.

    PubMed

    Kapila, Rishabh; Matsuda, Yukiko; Araki, Kazuyuki; Okano, Tomohiro; Nishikawa, Keiichi; Sano, Tsukasa

    2015-01-01

    This study compared Ultra Speed Occlusal Film (USOF) and 3 digital systems in determining the radiopacity of 5 different restorative resins in terms of equivalents of aluminum thickness. Whether those digital systems could be used to determine whether radiopacity was in line with International Organization for Standardization (ISO) recommendations was also investigated. Disks of each of 5 restorative resins and an aluminum step wedge were exposed at 65 kVp and 10 mA on USOF and imaged with each digital system. Optical density on the film was measured with a transmission densitometer and the gray values on the digital images using Image J software. Graphs showing gray value/optical density to step wedge thickness were constructed. The aluminum equivalent was then calculated for all the resins using a regression equation. All the resins were more radiopaque than 1 mm of aluminum, and therefore met the ISO 4049 recommendations for restorative resins. Some resins showed statistically higher aluminum equivalents with digital imaging. The use of traditional X-ray films is declining, and digital systems offer many advantages, including an easy, fast, and reliable means of determining the radiopacity of dental materials. PMID:26657519

  16. Measurement of mass attenuation coefficients for YBaCuO superconductor at different energies

    NASA Astrophysics Data System (ADS)

    Çevik, U.; Baltas, H.; Çelik, S.; Karaca, I.; Kopya, I.

    2005-01-01

    The mass attenuation coefficients for Y2O3, BaCO3, CuO compounds, and solid-state forms of YBa2Cu3O7 superconductor were determined at energies of 57.5, 59.5, 65.2, 74.8, 77.1, 87.3, 94.6, 98.4, 122, and 136 keV. The samples were irradiated using a 241Am point source emitting 59.5 keV photon energies and a 57Co point source emitting 122 and 136 keV photon energies. The other energies were obtained using secondary targets such as Ta, Bi2O3, and (CH3COO)2UO22H2O. The gamma- and x-rays were counted by a Si(Li) detector with a resolution of 160 eV at 5.9 keV. Samples were selected on the basis of known composition and mass densities were measured using a densitometer. The experimental results obtained in this study are compared with theoretical values.

  17. The relationship of anthropometric measures to radiological features of the breast in premenopausal women.

    PubMed Central

    Boyd, N. F.; Lockwood, G. A.; Byng, J. W.; Little, L. E.; Yaffe, M. J.; Tritchler, D. L.

    1998-01-01

    We studied 273 premenopausal women recruited from mammography units who had different degrees of density of the breast parenchyma on mammography, in whom we measured height, weight and skinfold thicknesses. Mammograms were digitized to high spatial resolution by a scanning densitometer and images analysed to measure the area of dense tissue and the total area of the breast. Per cent density and the area of non-dense tissue were calculated from these measurements. We found that the mammographic measures had different associations with body size. Weight and the Quetelet index of obesity were strongly and positively associated with the area of non-dense tissue and with the total area of the breast, but less strongly and negatively correlated with the area of dense tissue. We also found a strong inverse relationship between the areas of radiologically dense and non-dense breast tissue. Statistical models containing anthropometric variables explained up to 8% of the variance in dense area, but explained up to 49% of the variance in non-dense area and 43% of variance in total area. These results suggest that aetiological studies in breast cancer that use mammographic density should consider dense and non-dense tissues separately. In addition to per cent density, methods should be examined that combine information from these two tissues. Images Figure 1 PMID:9820186

  18. Body composition in taller individuals using DXA: A validation study for athletic and non-athletic populations.

    PubMed

    Santos, Diana A; Gobbo, Luís A; Matias, Catarina N; Petroski, Edio L; Gonçalves, Ezequiel M; Cyrino, Edilson S; Minderico, Claudia S; Sardinha, Luís B; Silva, Analiza M

    2013-01-01

    Dual energy X-ray absorptiometry (DXA) cannot be used to evaluate participants taller than the scan area. We aimed to analyse the accuracy of bone mineral content, fat mass, and lean mass assessed with DXA whole-body scan and from the sum of two scans (head and trunk plus limbs). Participants were 31 athletes (13 males and 18 females) and 65 non-athletes (34 males and 31 females), that fit within the DXA scan area. Three scans were performed using a Hologic Explorer-W fan-beam densitometer: a whole-body scan used as the reference; a head scan; and a trunk and limbs scan. The sum of the head scan and the trunk and limbs scan was used as the alternative procedure. Multiple regression and agreement analysis were performed. Non-significant differences between methods were observed for fat mass (0.06 kg) and lean mass (-0.07 kg) while bone mineral content from the alternative procedure differed from the reference scan (0.009 kg). The alternative procedure explained > 99% of the variance in the reference scan and low limits of agreement were observed. Precision analysis indicated low pure errors and the higher coefficients of variation were found for fat mass (whole-body: 3.70%; subtotal: 4.05%). The method proposed is a valid and simple solution to be used in individuals taller than the DXA scan area, including athletes engaged in sports recognised for including very tall competitors. PMID:23092580

  19. Effects of neurosurgical titanium mesh on radiation dose

    SciTech Connect

    Patone, Hassisen . E-mail: hash.patone@mail.mcgill.ca; Barker, Jennifer; Roberge, David

    2006-01-01

    The purpose of this study was to determine the dosimetric impact of a neurosurgical titanium mesh in patients treated with 6- and 18-MV photon beams. The effects of a 0.4-mm-thick titanium mesh on the dose profile at 3 regions within a solid water phantom were measured using extended dose range-2 (EDR2) film for 6- and 18-MV photon beams. All measurements were performed with the titanium mesh placed at a depth of 1.5 cm in the phantom. Films were exposed immediately above the mesh, immediately below the mesh, and at a depth of 5 cm from the surface of the phantom. The films were scanned using a scanning densitometer. In the region directly above the titanium mesh, there was an increase in dose of 7.1% for 6-MV photons and 4.9% for 18-MV photons. Directly below the titanium mesh, there was an average decrease in dose of 1.5% for 6-MV photons and an increase of 1.0% for 18-MV photons. At 5-cm depth, for 6- and 18-MV photons, there was a decrease in dose of 2.2% and 0.6%, respectively. We concluded that for cranial irradiation with high-energy photons, the dosimetric impact of a 0.4-mm titanium mesh is small and does not require modification in treatment parameters.

  20. Effects of strontium ions on growth and dissolution of hydroxyapatite and on bone mineral detection.

    PubMed

    Christoffersen, J; Christoffersen, M R; Kolthoff, N; Bärenholdt, O

    1997-01-01

    Preparation and analyses of a series of hydroxyapatites (HA) containing 1-10 mol % of Ca2+ replaced by Sr2+ is reported. The solubility of these apatites is found to increase with increasing content of Sr2+, 10% SrHA dissolves faster than CaHA at given values of Ca2+ and phosphate concentrations, but with a similar rate at the same degree of saturation. Sr2+ is found to inhibit the rates of both dissolution and growth of CaHA and 10% SrHA at pH 7.2, CaHA being more strongly inhibited by Sr2+ than 10% SrHA. The effect of partial substitution of Ca2+ in hydroxyapatite by Sr2+ on bone mineral content (BMC) and bone mineral density (BMD) measured by dual energy X-ray absorptiometry has been studied using three commercial densitometers. Extrapolating the absorption data for up to 10% replacement of Ca2+ by Sr2+ to 100% substitution of Ca2+ by Sr2+ in HA leads to an apparent increase in BMC or BMD of about a factor of 10. This factor is in agreement with theoretical calculations using attenuation coefficients of the atoms concerned. It is concluded that existing BMC scanners register artificially high values of BMC if the bone contains significant amounts of Sr2+ or other metal ions with atomic number larger than calcium. PMID:8988347

  1. Identification of chemical-specific protein profiles in Daphnia magna using neural networks

    SciTech Connect

    Iamonte, T.; Broadt, T.; Bradley, B.

    1995-12-31

    One dimensional gel electrophoresis was performed on whole-animal homogenates of 10 Daphnia magna exposed for 48 hours to one toxic and one non-toxic concentration of 2,4-dinitrophenol and sodium pentachlorophenate, two uncouplers of oxidative phosphorylation; malathion, an organophosphate; and permethrine, a pyrethroid, along with culture water and solvent controls, as appropriate. Ten randomized complete block exposures were conducted to minimize among-cohort variability. The 10-animal samples were gel electrophoresed, visualized using neutral silver staining and digitized with a Molecular Dynamics personal laser densitometer equipped with ImageQuant software. Densitometric data were used in a commercial neural network software package to construct a learning set, or database, of the protein profiles induced by the known chemical treatments. Novel data sets were then presented to the neural network program for assignment to treatment categories. Although no differences in protein profile between controls and chemical treatments and among chemical treatments could be detected visually in one dimensional gels, the neural network was able to correctly assign each sample to the appropriate learned treatment category about 70 percent of the time. Key proteins used by the neural network software to learn the protein profile of each chemical were identified by molecular weight and assigned a relative importance for identification of that chemical.

  2. Arterial input function of an optical tracer for dynamic contrast enhanced imaging can be determined from pulse oximetry oxygen saturation measurements

    NASA Astrophysics Data System (ADS)

    Elliott, Jonathan T.; Wright, Eric A.; Tichauer, Kenneth M.; Diop, Mamadou; Morrison, Laura B.; Pogue, Brian W.; Lee, Ting-Yim; St. Lawrence, Keith

    2012-12-01

    In many cases, kinetic modeling requires that the arterial input function (AIF)—the time-dependent arterial concentration of a tracer—be characterized. A straightforward method to measure the AIF of red and near-infrared optical dyes (e.g., indocyanine green) using a pulse oximeter is presented. The method is motivated by the ubiquity of pulse oximeters used in both preclinical and clinical applications, as well as the gap in currently available technologies to measure AIFs in small animals. The method is based on quantifying the interference that is observed in the derived arterial oxygen saturation (SaO2) following a bolus injection of a light-absorbing dye. In other words, the change in SaO2 can be converted into dye concentration knowing the chromophore-specific extinction coefficients, the true arterial oxygen saturation, and total hemoglobin concentration. A simple error analysis was performed to highlight potential limitations of the approach, and a validation of the method was conducted in rabbits by comparing the pulse oximetry method with the AIF acquired using a pulse dye densitometer. Considering that determining the AIF is required for performing quantitative tracer kinetics, this method provides a flexible tool for measuring the arterial dye concentration that could be used in a variety of applications.

  3. A sensitometric comparison of Fuji Super HR-G and Kodak T-mat G panoramic films.

    PubMed

    Benson, B W; Frederiksen, N L

    1995-05-01

    Film contrast, relative speed, and resolution of Fuji Super HR-G panoramic film were determined according to specifications of the American National Standards Institute and compared with those of Kodak T-mat G panoramic film. The films were simultaneously exposed by Kodak Lanex regular intensifying screens with time-scale sensitometry. Optical density was read with a digital densitometer, and characteristic curves were plotted and analyzed by polynomial and linear regression. The average gradients of the linear regression curves between 0.25 and 2.00 optical density units above base plus fog were taken as contrast (HR-G: 1.831, T-mat G: 1.712). Relative speed, when exposed with Lanex regular intensifying screens and calculated at 1.00 optical density unit above base plus fog, was 412 for HR-G. A speed of 400 was chosen for T-mat G to match Kodak consumer information. Resolution for both films was similar. These findings suggest that Fuji Super HR-G panoramic film develops similar contrast, speed, and resolution to Kodak T-mat G panoramic film. PMID:7600231

  4. Solids circulation around a jet in a fluidized bed gasifier. Final technical report, September 1, 1978-September 30, 1980

    SciTech Connect

    Gidaspow, D.; Ettehadieh, B.; Lin, C.; Goyal, A.; Lyczkowski, R.W.

    1980-01-01

    The object of this investigation was to develop an experimentally verified hydrodynamic model to predict solids circulation around a jet in a fluidized bed gasifier. Hydrodynamic models of fluidization use the principles of conservation of mass, momentum and energy. To account for unequal velocities of solid and fluid phases, separate phase momentum balances are developed. Other fluid bed models used in the scale-up of gasifiers do not employ the principles of conservation of momentum. Therefore, these models cannot predict fluid and particle motion. In such models solids mixing is described by means of empirical transfer coefficients. A two dimensional unsteady state computer code was developed to give gas and solid velocities, void fractions and pressure in a fluid bed with a jet. The growth, propagation and collapse of bubbles was calculated. Time-averaged void fractions were calculated that showed an agreement with void fractions measured with a gamma ray densitometer. Calculated gas and solid velocities in the jet appeared to be reasonable. Pressure and void oscillations also appear to be reasonable. A simple analytical formula for the rate of solids circulation was developed from the equations of change. It agrees with Westinghouse fluidization data in a bed with a draft tube. One dimensional hydrodynamic models were applied to modeling of entrained-flow coal gasification reactors and compared with data. Further development of the hydrodynamic models should make the scale-up and simulation of fluidized bed reactors a reality.

  5. Possibility of tree selection and breeding for genetic improvement of wood properties of Gmelina arborea

    SciTech Connect

    Akachuku, A.E.

    1984-06-01

    Wood samples of Gmelina arborea were collected from Nigerian plantations. The wood density was measured with an X-ray densitometer. Fiber length was measured with a modified map measurer. Fiber proportion was determined with a modification of Ladell's (1959) randomized dot technique. Considerable between-tree differences were observed in wood density, fiber length, fiber proportion, and sizes of trees of the same age, planted at the same spacing within the same environment. The magnitude of within-tree variations in these wood properties was different in trees within the same plot. Some individual trees combined comparatively high density, fiber length, and fiber proportion with fast growth rate and uniform wood. There was sufficient phenotypic variation to encourage genetic improvement of the wood properties and growth rate by selecting and breeding trees with higher values of these traits. Tree selection should be based on a preliminary screening for tree form and volume growth followed by a second selection for the desired wood properties.

  6. Radiopacity of different resin-based and conventional luting cements compared to human and bovine teeth.

    PubMed

    Pekkan, Gürel; Ozcan, Mutlu

    2012-02-01

    This study evaluated the radiopacity of different resin-based luting materials and compared the results to human and bovine dental hard tissues. Disc specimens (N=130, n=10 per group) (diameter: 6 mm, thickness: 1 mm) were prepared from 10 resin-based and 3 conventional luting cements. Human canine dentin (n=10), bovine enamel (n=10), bovine dentin (n=10) and Aluminium (Al) step wedge were used as references. The optical density values of each material were measured from radiographic images using a transmission densitometer. Al step wedge thickness and optical density values were plotted and equivalent Al thickness values were determined for radiopacity measurements of each material. The radiopacity values of conventional cements and two resin luting materials (Rely X Unicem and Variolink II), were significantly higher than that of bovine enamel that could be preferred for restorations cemented on enamel. Since all examined resin-based luting materials showed radiopacity values equivalent to or greater than that of human and bovine dentin, they could be considered suitable for the restorations cemented on dentin. PMID:22277608

  7. Sensitivity and comparison evaluation of Saturn 5 liquid penetrants

    NASA Technical Reports Server (NTRS)

    Jones, G. H.

    1973-01-01

    Results of a sensitivity and comparison evaluation performed on six liquid penetrants that were used on the Saturn 5 vehicle and other space hardware to detect surface discontinuities are described. The relationship between penetrant materials and crack definition capabilities, the optimum penetrant materials evaluation method, and the optimum measurement methods for crack dimensions were investigated. A unique method of precise developer thickness control was envolved, utilizing clear radiographic film and a densitometer. The method of evaluation included five aluminum alloy, 2219-T87, specimens that were heated and then quenched in cold water to produce cracks. The six penetrants were then applied, one at a time, and the crack indications were counted and recorded for each penetrant for comparison purposes. Measurements were made by determining the visual crack indications per linear inch and then sectioning the specimens for a metallographic count of the cracks present. This method provided a numerical approach for assigning a sensitivity index number to the penetrants. Of the six penetrants evaluated, two were not satisfactory (one was not sufficiently sensitive and the other was to sensitive, giving false indications). The other four were satisfactory with approximately the same sensitivity in the range of 78 to 80.5 percent of total cracks detected.

  8. Precocious Ossification of the Tympanoperiotic Bone in Fetal and Newborn Dolphins: An Evolutionary Adaptation to the Aquatic Environment?

    PubMed

    Cozzi, Bruno; Podestà, Michela; Vaccaro, Calogero; Poggi, Roberto; Mazzariol, Sandro; Huggenberger, Stefan; Zotti, Alessandro

    2015-07-01

    The present study, performed with a dual-energy X-ray (DXA) bone densitometer on a series of fetal and newborn striped and short-beaked common dolphins, shows that the bone density of the area of the tympanic bulla within the tympanoperiotic complex starts with 0.483 g cm(-2) in 5- to 6-month-old specimens of striped (or common) dolphin fetuses and reaches 1.841 g cm(-2) in newborn striped dolphins, with values consistently higher than in other parts of the skull or elsewhere in the skeleton. The same results apply to the common bottlenose dolphins, in which the area of the tympanic bulla has a density of 0.312 g cm(-2) in 5-month-old specimens and becomes four times as much in newborns. Regardless of the areal bone density results correlated to the DXA-technique, comparisons with DXA-bone density data in the literature referred to other mammals emphasize the presence of very high mineral deposition in the area of the tympanoperiotic bone in fetal and newborn dolphins and the most dense part of it belongs to the tympanic bulla. The early osseous maturation of the tympanic bulla area may be compared to what described in fin whales and may represent an unique ontogenetic and phylogenetic feature of cetaceans, possibly related to the development of essential acoustic sense and establishment of immediate post-natal mother-calf relationship. PMID:25676796

  9. Reduced secretion of IgA to skin surface of patients with atopic dermatitis.

    PubMed

    Imayama, S; Shimozono, Y; Hoashi, M; Yasumoto, S; Ohta, S; Yoneyama, K; Hori, Y

    1994-08-01

    To investigate whether the secretory form of immunoglobulin A (sIgA) was reduced on the skin surface in atopic dermatitis, the amount of sIgA present in sweat was measured in 40 patients with atopic dermatitis and in 50 healthy volunteers by attaching a cellulose membrane disk (10 x 10 mm) to the inner aspect of the upper arm skin for 24 hours. The secretory form of IgA, which was absorbed to the membrane and accumulated during the period of application, was revealed as dots by an enzyme immunoassay in which antibodies for IgA and for the secretory component were used. The density and number of dots (per mm2/day), which corresponded to the openings of eccrine excretory ducts, were determined with a densitometer. The mean amount of sIgA secreted by those patients was 3.86 +/- 0.71 pg/mm2/day (range, 0 to 21.17 pg/mm2/day), whereas that of the control subjects was significantly higher (p < 0.001), 16.79 +/- 2.80 pg/mm2/day (range, 0.79 to 133.77 pg/mm2/day). This may be related to the high incidence of bacterial and viral skin infections seen in patients with atopic dermatitis, and in addition, to the development of eczematous lesions through a defect in ridding the skin of allergens and/or microorganisms. PMID:8064071

  10. Three-terminal capacitance cell for stopped-flow measurements of very dilute solutions

    NASA Astrophysics Data System (ADS)

    Tjahjono, Martin; Davis, Thomas; Garland, Marc

    2007-02-01

    A capacitance cell has been designed, constructed, and tested for stopped-flow measurements of very dilute low-relative permittivity liquid solutions. The capacitance cell utilizes a three-terminal design and is connected to ultrahigh sensitivity capacitance bridge. The cell was designed for operating conditions T ≈243.15-373.15K and P ≈0-1MPa and tested with pure anhydrous cyclohexane and with dilute acetone/cyclohexane solutions at 298.15K and 0.1MPa under an argon blanket in a thermostated bath with a temperature variation of <0.001K. Details of the design and materials of construction are reported. The measured relative permittivity of cyclohexane was 2.015 565, in agreement with the literature, and the long term variation of the measurement was ±5×10-6. The relative permittivities of the acetone/cyclohexane solutions were very linear (R2=0.9997) in the measured interval of 0.001-0.008mole fraction. These measurements confirm that the design specifications for stability and resolution/sensitivity of better than 1×10-5 have been realized. Finally, the present online capacitance cell was connected online to an ultrasensitive densitometer and ultrasensitive refractometer and binary acetone/cyclohexane solutions were measured. The measurements of density, refractive index, and relative permittivity were combined to provide a dipole moment of acetone of 2.750±0.005D, which is in good agreement with literature.

  11. Bone mineral density of skeletal remains: Discordant results between chemical analysis and DXA method.

    PubMed

    Sutlovic, Davorka; Boric, Igor; Sliskovic, Livia; Popovic, Marijana; Knezovic, Zlatka; Nikolic, Ivana; Vucinovic, Ana; Vucinovic, Zoran

    2016-05-01

    Dual-energy X-ray absorptiometry (DXA) scanning is a gold standard for bone mineral density measurement and diagnosis of primary and secondary osteoporosis in living persons. DXA is becoming widespread when analysing archaeological material, and is considered to provide an accurate diagnosis of osteoporosis in skeletal samples. The aim of this study was to explain the differences in results between bone mineral density (obtained with DXA) and chemical determination of calcium and phosphorus concentrations in skeletal remains. We examined bone mineral density (BMD) and mineral content of femoral bone samples exhumed from mass graves of the Second World War. BMD was determined by Hologic QDR 4500 C (S/N 48034) Bone Densitometer. Concentrations of calcium and phosphorus were determined with AAS (Atomic absorption spectroscopy) and UV/VIS (Ultraviolet-visible) spectroscopy. The results obtained in this study do not support the hypothesis according to which BMD measured by DXA scan has positive correlation with chemically determined concentrations of calcium and phosphorus in bones, especially in acidic soils where there was significant impact of diagenesis observed. PMID:27161916

  12. Solids flow rate measurement in dense slurries

    SciTech Connect

    Porges, K.G.; Doss, E.D.

    1993-09-01

    Accurate and rapid flow rate measurement of solids in dense slurries remains an unsolved technical problem, with important industrial applications in chemical processing plants and long-distance solids conveyance. In a hostile two-phase medium, such a measurement calls for two independent parameter determinations, both by non-intrusive means. Typically, dense slurries tend to flow in laminar, non-Newtonian mode, eliminating most conventional means that usually rely on calibration (which becomes more difficult and costly for high pressure and temperature media). These issues are reviewed, and specific solutions are recommended in this report. Detailed calculations that lead to improved measuring device designs are presented for both bulk density and average velocity measurements. Cross-correlation, chosen here for the latter task, has long been too inaccurate for practical applications. The cause and the cure of this deficiency are discussed using theory-supported modeling. Fluid Mechanics are used to develop the velocity profiles of laminar non-Newtonian flow in a rectangular duct. This geometry uniquely allows the design of highly accurate `capacitive` devices and also lends itself to gamma transmission densitometry on an absolute basis. An absolute readout, though of less accuracy, is also available from a capacitive densitometer and a pair of capacitive sensors yields signals suitable for cross-correlation velocity measurement.

  13. Digital image analyser for autoradiography

    SciTech Connect

    Muth, R.A.; Plotnick, J.

    1985-05-01

    The most critical parameter in quantitative autoradiography for assay of tissue concentrations of tracers is the ability to obtain precise and accurate measurements of optical density of the images. Existing high precision systems for image analysis, rotating drum densitometers, are expensive, suffer from mechanical problems and are slow. More moderately priced and reliable video camera based systems are available, but their outputs generally do not have the uniformity and stability necessary for high resolution quantitative autoradiography. The authors have designed and constructed an image analyser optimized for quantitative single and multiple tracer autoradiography which the authors refer to as a memory-mapped charged-coupled device scanner (MM-CCD). The input is from a linear array of CCD's which is used to optically scan the autoradiograph. Images are digitized into 512 x 512 picture elements with 256 gray levels and the data is stored in buffer video memory in less than two seconds. Images can then be transferred to RAM memory by direct memory-mapping for further processing. Arterial blood curve data and optical density-calibrated standards data can be entered and the optical density images can be converted automatically to tracer concentration or functional images. In double tracer studies, images produced from both exposures can be stored and processed in RAM to yield ''pure'' individual tracer concentration or functional images. Any processed image can be transmitted back to the buffer memory to be viewed on a monitor and processed for region of interest analysis.

  14. Densitometric evaluation of four rapid dental film processing solutions.

    PubMed

    Matthee, M J; Seeliger, J E

    1991-09-01

    The aim of this study was to evaluate densitometrically four rapid processing solutions for dental films; also to identify those combinations of film, solution and temperature which produced the best results in terms of radiographic contrast and relative film speed at a given temperature. The film types used were Agfa Dentus M2, Flow X-ray and Kodak Ultra-speed while the rapid processing solutions tested were Kolchem Rapid Dev 1, Kolchem Rapid Dev 2, MEMS Ultra-Neg and Siemens Insta-Neg. An aluminium step-wedge was radiographed under standardized conditions. Processing was done manually at 18, 20, 22, 25, 27, 29 and 32 degrees C, the temperatures being controlled with the aid of two Julabo thermostatically controlled immersion circulators, to ensure constant temperatures. Unexposed films were processed at each temperature setting to determine base plus fog values. Densitometric readings were taken using a digital densitometer, and base plus fog values were subtracted from each reading. Radiographic contrast and relative film speed were calculated and the data obtained subjected to statistical analysis using Duncan's Multiple Range Test. It was concluded that Agfa Dentus M2 film processed with Kolchem Rapid Dev 2 at 18 degrees C gave the highest radiographic contrast of 0.44 and relative film speed of 4.36. All base plus fog values were within the acceptable limit of 0.25. PMID:1820681

  15. Engineering assessment of inactive uranium mill tailings, Spook site, Converse County, Wyoming

    SciTech Connect

    Not Available

    1981-10-01

    Ford, Bacon and Davis Utah Inc. has reevaluated the Spook site in order to revise the December 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings 48 mi northeast of Casper, in Converse County, Wyoming. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 187,000 tons of tailings at the Spook site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover makes and gamma densitometers for measuring cross-sectionally averaged mass velocity in steady steam-water flow are presented. The results are interpreted ntation.

  16. Critical parameters and PVT properties for R-404A

    SciTech Connect

    Fujiwara, K.; Nakamura, S.; Noguchi, M.

    1998-11-01

    The critical parameters of R-404A. a ternary mixture of 44 mass % pentafluoroethane (R-125), 52 mass % 1,1,1-trifluoroethane (R-143a), and 4 mass % 1,1,1,2-tetrafluoroethane (R-134a), were measured by visual observation of the meniscus in an optical cell. The critical pressure, density, and temperature were determined to be (3.726 {+-} 0.002) MPa, (490 {+-} 3) kg/m{sup 3}, and (345.15 {+-} 0.01) K, respectively. Forty single-phase PVT properties have been measured with a constant-volume method along three isochores in a range of densities from 487 to 493 kg/m{sup 3}, temperatures from 345 K to 393 K, and pressures from 3.7 to 7.8 MPa. One hundred and nineteen densities of R-404A have been measured with a vibrating-tube densitometer over a density range from 47 to 1247 kg/m{sup 2} along eight isotherms between 263 K and 403 K and at pressures between 1.5 MPa and 15 MPa. An 18-term modified Benedict-Webb-Rubin equation of state for R-404A was developed using the PVT property data.

  17. Estimation of In vivo Cancellous Bone Elasticity

    NASA Astrophysics Data System (ADS)

    Otani, Takahiko; Mano, Isao; Tsujimoto, Toshiyuki; Yamamoto, Tadahito; Teshima, Ryota; Naka, Hiroshi

    2009-07-01

    The effect of decreasing bone density (a symptom of osteoporosis) is greater for cancellous bone than for dense cortical bone, because cancellous bone is metabolically more active. Therefore, the bone density or bone mineral density of cancellous bone is generally used to estimate the onset of osteoporosis. Elasticity or elastic constant is a fundamental mechanical parameter and is directly related to the mechanical strength of bone. Accordingly, elasticity is a preferable parameter for assessing fracture risk. A novel ultrasonic bone densitometer LD-100 has been developed to determine the mass density and elasticity of cancellous bone with a spatial resolution comparable to that of peripheral quantitative computed tomography. Bone density and bone elasticity are evaluated using ultrasonic parameters based on fast and slow waves in cancellous bone by modeling the ultrasonic wave propagation path. Elasticity is deduced from the measured bone density and the propagation speed of the fast wave. Thus, the elasticity of cancellous bone is approximately expressed by a cubic equation of bone density.

  18. Nucleus fingerprinting for the unique identification of Feulgen-stained nuclei

    NASA Astrophysics Data System (ADS)

    Friedrich, David; Brozio, Matthias; Bell, André; Biesterfeld, Stefan; Böcking, Alfred; Aach, Til

    2012-03-01

    DNA Image Cytometry is a method for non-invasive cancer diagnosis which measures the DNA content of Feulgen-stained nuclei. DNA content is measured using a microscope system equipped with a digital camera as a densitometer and estimating the DNA content from the absorption of light when passing through the nuclei. However, a DNA Image Cytometry measurement is only valid if each nucleus is only measured once. To assist the user in preventing multiple measurements of the same nucleus, we have developed a unique digital identifier for the characterization of Feulgen-stained nuclei, the so called Nucleus Fingerprint. Only nuclei with a new fingerprint can be added to the measurement. This fingerprint is based on basic nucleus features, the contour of the nucleus and the spatial relationship to nuclei in the vicinity. Based on this characterization, a classifier for testing two nuclei for identity is presented. In a pairwise comparison of ~40000 pairs of mutually different nuclei, 99.5% were classified as different. In another 450 tests, the fingerprints of the same nucleus recorded a second time were in all cases judged identical. We therefore conclude that our Nucleus Fingerprint approach robustly prevents the repeated measurement of nuclei in DNA Image Cytometry.

  19. [MINERAL BONE DENSITY AND BODY COMPOSITION IN PARTICIPANTS IN EXPERIMENT MARS-500].

    PubMed

    Novikov, V E; Oganov, V S; Kabitskaya, O E; Murashko, L M; Naidina, V P; Chernikhova, E A

    2016-01-01

    Investigations of the bone system and body composition in Mars-500 test-subjects (prior to and on completion of the experiment) involved dual-energy X-ray absorptiometry (DXA) using the HOLOGIC Delphy densitometer and the protocol performed to examine cosmonauts. Bone density of lumber vertebrae and femoral proximal epiphysis, and body composition were measured. Reliable changes in vertebral density found in 3 test-subjects displayed different trends from +2.6 to -2.4%. At the same time, the experiment decreased significantly mineral density of the femoral proximal epiphysis, including the neck, in all test-subjects. Four test-subjects had cranial mineralization increased by 5-9%, same as in some cosmonauts after space flight. All tests-subjects incurred adipose loss from 2 to 7 kg; one test-subject lost 20 kg, i.e. his adipose mass became three times less. Changes in lean mass (1-3 kg) typically were negative; as for changes in lean mass of extremities, they could be linked with adherence to one or another type of physical activity. Therefore, extended exposure to confinement may affect mineralization of some parts of the skeleton. Unlike real space missions and long-term bedrest studies conducted at the Institute of Biomedical Problems in the past, Mars-500 did not cause clinically significant mineral losses (osteoporosis, osteopenia), probably because of the absence of effects of microgravity. PMID:27344855

  20. Evaluation of a Multiwavelength Characterization of Brown and Black Carbon from Filter Samples

    NASA Astrophysics Data System (ADS)

    Johnson, Megan M.

    An ultraviolet -- visible (UV-VIS) spectrometer coupled with an integrating sphere was used to measure diffuse reflectance and transmittance of particulate matter (PM) samples collected on quartz-fiber (QF) and Teflon-membrane (TM) filter media over the wavelength range 250 -- 1000 nm at 1 nm resolution. These measurements were used to calculate PM sample attenuation, absorption, and Angstrom absorption exponents (AAE). Samples included laboratory generated source samples (e.g. biomass burning emissions, diesel engine exhaust, and resuspended dusts) and ambient samples. PM sample attenuation and absorption were compared to other PM light absorption measurement methods including densitometer, dual-wavelength (370 & 880 nm) transmissometer, and 3-lambda (405, 532, 781 nm) photoacoustic spectrometer (PAS). Large differences were found between filter-based methods and QF and TM absorption was found to be higher than PAS by average factors of 5.1 and 3.6, respectively. AAE values calculated for all samples compared well with values previously reported in literature. Comparison of the filter media showed that attenuation and absorption values from TM samples are, on average, ˜1/2 of the values obtained using QF samples. Filter media comparison also revealed evidence of shadowing effects on TM filter media with high sample loading. Comparison of absorption approximation methods using various AAEs and a power law extrapolation exhibited large differences in radiative forcing estimates, indicating that PM absorption is not always well represented by the power law assumption.

  1. Oligosaccharides in several Philippine indigenous food legumes: determination, localization and removal.

    PubMed

    Revilleza, M J; Mendoza, E M; Raymundo, L C

    1990-01-01

    The oligosaccharide profile of raw mature seeds of seven different legumes indigenous to the Philippines was measured in 70% ethanol extracts of the seeds by thin layer chromatography using HPTLC plates and quantified by a densitometer. Based on the results, the legumes could be ranked according to decreasing oligosaccharide content or flatulence potential as follows: Sam-samping (Clitoria ternatea) greater than hyacinth bean (Dolichos lablab) greater than sabawel (Mucuna pruriens) greater than lima bean (Phaseolus lunatus) greater than swordbean (Canavalia gladiata) greater than rice bean (Vigna umbellata) greater than jack bean (Canavalia ensiformis). Sam-samping had 4.79% total oligosaccharides and hyacinth bean or batao, 3.66%. A jack bean accession had 1.79% oligosaccharides. Simple processing methods were tested to detoxify the oligosaccharides. Soaking the batao seeds had no effect while boiling even resulted in a net 23-31% increase in the levels of raffinose, stachyose and verbascose. On the other hand, two min of dry roasting resulted in complete removal of oligosaccharides whereas germination resulted in about 30-40% decrease after 1 and 2 days, respectively. PMID:2345736

  2. Geographic applications of ERTS-A imagery to rural landscape change

    NASA Technical Reports Server (NTRS)

    Rehder, J. B. (Principal Investigator)

    1972-01-01

    There are no author-identified significant results in this report. The study area, centered on Knoxville, Tennessee, encompasses nearly 20,000 square miles. The Knoxville Test Site, an 11 x 21 mile area over the city of Knoxville and the western portion of Knox County, has been chosen for the analysis of landscape change detection associated with urban growth. The second area, the Cumberland Plateau Test Site, exhibits landscape change through forest alterations and landform disturbances associated with strip mining in the area and was so chosen for its sharp contrasts in physical and human phenomena as well as its change dynamics. Accomplishments since reception of ERTS-1 imagery include: (1) basic cataloging and classifying of the data into a filling system; (2) a densitometer analysis; (3) first look analysis; and (4) preparation of results from the project. Examples of all four bands of the MSS have been received and analyses reveal distinctive positive and negative reactions. Band 5 has been found to be best for landscape analysis of contrasts between urban and rural landscapes, and band 7 for topographic features and water surfaces. Preliminary results are summarized.

  3. Measurement of countercurrent phase separation and distribution in a two-dimensional test section

    SciTech Connect

    Bukhari, K M; Lahey, Jr, R T

    1984-01-01

    The degree of phase separation that occurs in the core of a pressurized water reactor (PWR) during various postulated accidents is an important consideration for studying the course of events during such accidents. The dependence of countercurrent phase separation and distribution phenomena on flow quality, mass flux and system geometry was studied experimentally in a two-dimensional (2-D) test section. A two-phase (air/water) mixture flowed upwards and single-phase water flowed downward along one side of the test section. This countercurrent flow configuration was intended to simulate the so-called chimney effect in the diabatic JAERI 2-D experiments in Japan. A large air/water loop used with a 91.44 cm x 91.44 cm x 1.27 cm test section to study phase separation and distribution effects. A traversing single beam gamma-densitometer was used to measure the chordal average void fractions at several elevations along the test section. Cross-plots between various flow conditions and geometries were made. An error analysis giving the total error in the void fraction measurements was also performed. High speed photographs were also made of the flow structure, to provide information on flow regimes. The photographic records and the void fraction and hydraulic inflow/outflow data are presented in a form suitable for the assessment of advanced generation computer codes (e.g., TRAC).

  4. Characterization of drug authenticity using thin-layer chromatography imaging with a mobile phone.

    PubMed

    Yu, Hojeong; Le, Huy M; Kaale, Eliangiringa; Long, Kenneth D; Layloff, Thomas; Lumetta, Steven S; Cunningham, Brian T

    2016-06-01

    Thin-layer chromatography (TLC) has a myriad of separation applications in chemistry, biology, and pharmacology due to its simplicity and low cost. While benchtop laboratory sample application and detection systems for TLC provide accurate quantitation of TLC spot positions and densities, there are many applications where inexpensive and portable instruments would greatly expand the applicability of the technology. In this work, we demonstrate identity verification and concentration determination of pharmaceutical compounds via TLC using a custom 3D-printed cradle that interfaces with an ordinary mobile phone. The cradle holds the mobile phone's internal, rear-facing camera in a fixed position relative to a UV lamp and a TLC plate that includes a phosphor in the stationary phase. Analysis of photographs thus reveals the locations and intensities of principal spots of UV--absorbing drugs. Automated image analysis software determines the center location and density of dark spots, which, using integrated calibration spots of known drug compounds and concentrations, can be used to determine if a drug has been diluted or substituted. Two independent image processing approaches have been developed that may be selected based upon the processing capabilities of the smartphone. Each approach is able to discern 5% drug concentration differences. Using single-component solutions of nevirapine, amodiaquine, and paracetamol that have been manually applied, the mobile phone-based detection instrument provides measurements that are equivalent to those obtained with a commercially available lab-based desktop TLC densitometer. PMID:27015410

  5. The density and photosensitivity of human rhodopsin in the living retina

    PubMed Central

    Alpern, M.; Pugh, E. N.

    1974-01-01

    1. The visual pigment in a 5° circular patch of the living human retina 18° temporal from the fovea was studied with the Rushton retinal densitometer. The measuring light (570 nm) was selected to obviate artifacts from colour photoproducts. 2. The action spectrum of a 10% bleach agrees well with the action spectrum at absolute threshold for the same patch of retina. The quantized C.I.E. scotopic spectral sensitivity curve is a good description of both spectra. Therefore, the visual pigment studied must be human rhodopsin. 3. Its density has been estimated in five different ways. The results are in reasonable agreement. The optical density of human rhodopsin in vivo is about 0·35 (common logarithmic units) at its γmax. 4. The photosensitivity of human rhodopsin in vivo was determined by studying its rate of bleaching in response to steps of monochromatic light exposed to the dark adapted eye, by measuring the amount bleached in the steady state by monochromatic lights as well as the amount bleached by 10 sec flashes of white light. 5. The results obtained by the different methods are in good agreement with each other and with previous estimates made by others using white light. 6. The photosensitivity of human rhodopsin in vivo [εγmax = 62,000 to 120,000 l./cm mole] is much higher than expected from in vitro measurements. PMID:4825455

  6. In vivo performance of a matrix-based quantitative ultrasound imaging device dedicated to calcaneus investigation.

    PubMed

    Gomez, M A; Defontaine, M; Giraudeau, B; Camus, E; Colin, L; Laugier, P; Patat, F

    2002-10-01

    We developed a prototype of an ultrasound (US) bone matrix densitometer, the BEAM scanner, in the context of a European Space Agency research program. This device, which is a contact imaging device, was designed to overcome the limitations of immersion devices in space. Broadband US attenuation (BUA) and speed of sound (SOS) parameters were calculated from the radiofrequency (RF) signal. The principle aim of this study was to evaluate in vivo performance in direct comparison with a currently available device (UBIS 3000, DMS, France). The short-term precision of the BEAM scanner for BUA was estimated at 2.8%, whereas it was 2.3% with UBIS 3000. The short-term precision for SOS was 0.3%, and this was the same as the coefficient of variation (CV) of the UBIS 3000. CVs of 3.4% and 0.6% for midterm precision were found for BUA and SOS, respectively, and UBIS 3000 scores were 3% and 0.4%, respectively. This preliminary study demonstrates the high performance of the BEAM scanner and its new concept offers a wide range of improvements and new applications. PMID:12467855

  7. Measurements of bone mineral density and stiffness index in young Saudi females

    PubMed Central

    Hammad, Lina Fahmi

    2016-01-01

    Objective: To examine the ability to use Quantitative Ultrasonography (QUS) densitometer for screening of osteoporosis and osteopenia by comparing QUS values obtained at the calcaneus region to bone mineral density (BMD) values measured at the spine and the neck of the femur using Dual Energy X-ray Absorbemetry (DXA). Methods: QUS (in the calcaneus region) and DXA (the spine and the neck of femur respectively) measurements were performed in 101 females. Results: The precision of the QUS parameters varied from 1.77-1.78, whereas the reliability ranged from 92.2%-98.6%. For the QUS parameters variability between subjects was greater than that within subjects. Positive correlation were found between stiffness index (SI) and BMDspine and BMDN.femur (r= 0.29 & r=0.25 respectively, P < 0.05) and a strong positive correlation between T-scorecalcaneus and both T-scoreSpine and T-scoreN.femur (r= 0.5 & r=0.58 respectively, P < 0.01). Conclusions: QUS is a reliable technique to be used in combination with DXA for the investigation of osteopenia and osteoporosis. PMID:27182248

  8. Female breast carcinomas: nuclear and cytoplasmic proteins versus steroid receptors.

    PubMed

    Bryś, M; Romanowicz-Makowska, H; Nawrocka, A; Krajewska, W M

    2000-01-01

    Nuclear and cytoplasmic proteins of human female breast cancer were analysed by one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Oestrogen receptor and progesterone receptor expression was determined by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method. The electropherograms were developed by silver nitrate staining and quantitative analysis was carried out by video densitometer using the software Gel-Pro Analyzer. Nuclear and cytoplasmic proteins of breast carcinomas and normal tissue differed both qualitatively and quantitatively. Nuclear polypeptides of 108, 53 and 48 kD as well as the 36 kD cytoplasmic polypeptide were specific for tumour samples, while the 51 kD nuclear polypeptide was detected only in normal tissue. Quantitative differences in band density were noted in the 32 kD nuclear polypeptide. This polypeptide was expressed in greatest concentration in infiltrating ductal carcinomas which also indicated the greatest oestrogen receptor gene expression. This relationship appeared to be statistically significant (p < 0.005). No correlations were evident between the 32 kD protein expression and the progesterone receptor gene expression in any of the tissue types examined, nor between the 32 kD protein and the patient's age or tumour grade. PMID:10756981

  9. Safety basis for the 241-AN-107 mixer pump installation and caustic addition

    SciTech Connect

    Van Vleet, R.J.

    1994-10-05

    This safety Basis was prepared to determine whether or not the proposed activities of installing a 76 HP jet mixer pump and the addition of approximately 50,000 gallons of 19 M (50:50 wt %) aqueous caustic are within the safety envelope as described by Tank Farms (chapter six of WHC-SD-WM-ISB-001, Rev. 0). The safety basis covers the components, structures and systems for the caustic addition and mixer pump installation. These include: installation of the mixer pump and monitoring equipment; operation of the mixer pump, process monitoring equipment and caustic addition; the pump stand, caustic addition skid, the electrical skid, the video camera system and the two densitometers. Also covered is the removal and decontamination of the mixer pump and process monitoring system. Authority for this safety basis is WHC-IP-0842 (Waste Tank Administration). Section 15.9, Rev. 2 (Unreviewed Safety Questions) of WHC-IP-0842 requires that an evaluation be performed for all physical modifications.

  10. Recognizing Banknote Fitness with a Visible Light One Dimensional Line Image Sensor

    PubMed Central

    Pham, Tuyen Danh; Park, Young Ho; Kwon, Seung Yong; Nguyen, Dat Tien; Vokhidov, Husan; Park, Kang Ryoung; Jeong, Dae Sik; Yoon, Sungsoo

    2015-01-01

    In general, dirty banknotes that have creases or soiled surfaces should be replaced by new banknotes, whereas clean banknotes should be recirculated. Therefore, the accurate classification of banknote fitness when sorting paper currency is an important and challenging task. Most previous research has focused on sensors that used visible, infrared, and ultraviolet light. Furthermore, there was little previous research on the fitness classification for Indian paper currency. Therefore, we propose a new method for classifying the fitness of Indian banknotes, with a one-dimensional line image sensor that uses only visible light. The fitness of banknotes is usually determined by various factors such as soiling, creases, and tears, etc. although we just consider banknote soiling in our research. This research is novel in the following four ways: first, there has been little research conducted on fitness classification for the Indian Rupee using visible-light images. Second, the classification is conducted based on the features extracted from the regions of interest (ROIs), which contain little texture. Third, 1-level discrete wavelet transformation (DWT) is used to extract the features for discriminating between fit and unfit banknotes. Fourth, the optimal DWT features that represent the fitness and unfitness of banknotes are selected based on linear regression analysis with ground-truth data measured by densitometer. In addition, the selected features are used as the inputs to a support vector machine (SVM) for the final classification of banknote fitness. Experimental results showed that our method outperforms other methods. PMID:26343654

  11. Electrophoretic Porosimetry of Sol-Gels

    NASA Technical Reports Server (NTRS)

    Snow, L. A.; Smith, D. D.; Sibille, L.; Hunt, A. J.; Ng, J.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    It has been hypothesized that gravity has an effect on the formation and resulting microstructure of sol-gels. In order to more clearly resolve the effect of gravity, pores may be non-destructively analyzed in the wet gel, circumventing the shrinkage and coarsening associated with the drying procedure. We discuss the development of an electrophoretic technique, analogous to affinity chromatography, for the determination of pore size distribution and its application to silica gels. Specifically a monodisperse charged dye is monitored by an optical densitometer as it moves through the wet gel under the influence of an electric field. The transmittance data (output) represents the convolution of the dye concentration profile at the beginning of the run (input) with the pore size distribution (transfer function), i.e. linear systems theory applies. Because of the practical difficulty in producing a delta function input dye profile we prefer instead to use a step function. Average pore size is then related to the velocity of this dye front, while the pore size distribution is related to the spreading of the front. Preliminary results of this electrophoretic porosimetry and its application to ground and space-grown samples will be discussed.

  12. Osteoporosis screening is unjustifiably low in older African-American women.

    PubMed Central

    Wilkins, Consuelo H.; Goldfeder, Jason S.

    2004-01-01

    BACKGROUND: More than one million Americans suffer osteoporotic fractures yearly, resulting in a marked increase in morbidity and mortality. Despite a decrease in bone mineral density with increasing age in all ethnic groups and both genders, preventative and therapeutics efforts in osteoporosis have been focused on caucasian and Asian women. This study assesses the osteoporosis screening practices and the frequency of low bone density in a primarily African-American population of older women. METHODS: Medical records of 252 women at risk for osteoporosis were reviewed for the diagnosis of osteoporosis, prior osteoporosis screening, prior breast cancer screening, and the use of calcium, vitamin D or estrogen. Subsequently, 128 women were assessed for risk factors for osteoporosis, and their bone mineral density was measured using a peripheral bone densitometer. RESULTS: Osteoporosis screening had been performed in 11.5% of the subjects. Of the women evaluated by peripheral bone densitometry, 44.5% of all women, 40.4% of African-American women, and 53.3% of caucasian women had abnormally low bone density measurements. The frequency of abnormal bone density increased with both increasing age and decreasing body mass index. CONCLUSIONS: Although few women in this population were previously screened for osteoporosis, low bone density occurred in African-American women at substantial rates. Increasing age and low body mass are important risk factors for low bone density in African-American women. Ethnicity should not be used as an exclusion criterion for screening for osteoporosis. PMID:15101666

  13. [Dual x-ray absorptiometry in the diagnosis of osteoporosis].

    PubMed

    Vojtassák, J

    1993-01-01

    The author presents a review providing information on contemporary modern radiological possibilities as regards the diagnosis of osteoporosis at the First Orthopaedic Clinic in Bratislava. At present this department possesses a densitometer LUNAR DPX-L. This apparatus assesses the bone density on the basis of double X-ray absorption. The software available at present makes it possible to assess the bone density of the lumbar spine in the anterio-posterior and lateral projection, as well as the proximal femur and whole body. The mean time required for assessment is 4 mins. 24 secs. to 16 mins. 30 secs. The mean radiation load of the patient is 1.5 mrem, the maximal load 3.5 mrem. The apparatus compares the assessed density values with mean values of the healthy population, it evaluates automatically statistical values of the Z and T score. These results are presented either as a coloured graph or as values of bone mineral density and bone mineral content. The author explains in more detail the principle of modern densitometry and its development during the past three decades. PMID:8346691

  14. The effect of vehicle on physical properties and aerosolisation behaviour of disodium cromoglycate microparticles spray dried alone or with L-leucine.

    PubMed

    Najafabadi, Abdolhossien Rouholamini; Gilani, Kambiz; Barghi, Mohammadali; Rafiee-Tehrani, Morteza

    2004-11-01

    The aim of this study was to improve the aerosolisation behaviour of disodium cromogycate (DSCG), using spray drying technique. The effect of vehicle on the drug particle properties was investigated. L-leucine was selected as a natural antiadherent amino acid to improve the deagglomeration of DSCG particles. Spray dried samples of DSCG alone or with L-leucine were prepared from water and ethanol under the same conditions. The powder properties of the samples were examined by laser diffraction, helium densitometer, X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis. The in vitro deposition was determined, using an Andersen cascade impactor with a Spinhaler at a flow rate of 60 l/min. An amorphous form of the drug was obtained when water was used. However, crystal transformation of original DSCG in the presence of ethanol during spray drying resulted in production of elongated particles. These particles exhibited improved aerodynamic properties, compared to the amorphous and commercial materials. Significant differences in fine particle fraction were observed using the two vehicles. Co-spray drying of DSCG and L-leucine improved the deposition profiles of the drug. These results indicated that the change in crystal structure of DSCG during spray drying process was susceptible to the nature of the vehicle. A crystalline form of DSCG with good aerodynamic properties was achieved during spray drying process. In addition, the processing of DSCG with L-leucine in a single step using ethanol resulted in an improvement in dispersion properties of the drug particles. PMID:15488683

  15. Hemophilic bleeding evaluated by blood pool scanning.

    PubMed

    Green, D; Spies, S M; Rana, N A; Milgram, J W; Mintzer, R

    1981-06-30

    The technique of blood pool scanning was used to examine 15 hemophilic subjects. Employing an in vivo method for erythrocyte labeling with Technetium-99 m, a dynamic perfusion sequence is obtained using a scintillation camera positioned over the area to be examined. This demonstrates the vascularity of the tissue. Subsequently, equilibrium blood pool images of the area are obtained and analyzed with a densitometer to assess relative regional blood volume. In patients who were not bleeding but had chronic arthropathy, vascularity was not increased, and the blood volume of comparable joints was similar. By contrast, marked increases in vascularity and image density were observed in studies of acutely bleeding joints. Chronic hemarthroses were associated with persistent, but less marked increases in joint perfusion. Transient increases in joint vascularity were demonstrated after insertion of knee prostheses. In a patient with a thigh hematoma, the dimensions of the hemorrhage were clearly delineated. Since only a tracer dose of nuclide is infused intravenously, there are no allergic reactions or other side effects of the procedure. Blood pool scanning is a safe, non-invasive technique that augments clinical and radiographic evaluations, and provides a new dimension in the assessment of the hemophilic patient. PMID:6269248

  16. Radiation exposure of the hands and thyroid gland during percutaneous wiring of wrist and hand procedures.

    PubMed

    Bahari, Syah; Morris, Seamus; Broe, David; Taylor, Colm; Lenehan, Brian; McElwain, John

    2006-04-01

    The aim of this study was to investigate the radiation exposure of the hands and thyroid glands of orthopaedic surgeon and assistant during procedures involving percutaneous wiring of the hand and wrist. The radiation dose to the hand and thyroid glands was prospectively studied from a total of 30 percutaneous hand and wrist procedures. Four thermolucent densitometers were used to measure the radiation exposure. Cases were divided depending on fracture location (ie. wrist, metacarpal, phalangeal) and surgical experience (i.e. Senior House Officer, Registrar, Consultant). Mean radiation exposure in the hand for the surgeon was 0.80 mSv and 0.87 mSv for the assistant. There was a significant difference in the unshielded thyroid group compared to the shielded thyroid group (p < 0.05). The duration and number of exposure decreases with increasing experience. We also found a trend whereas we operate from proximal to distal (wrist to phalangeal), the total direct hand exposure increases. Radiation exposure in the hands and thyroid glands during percutaneous wiring of hand and wrist procedures were within the recommended limit. However, for the junior orthopaedic trainee, the risk of over radiating oneself is higher as the duration and number of exposure increases. We recommended the use of thyroid shield and adherence to the ALARA principle in any fluoroscopic assisted procedures. Routine monitoring of radiation exposure is essential in preventing radiation related disease. PMID:16768265

  17. TLC--densitometric method for qualitative analysis of betamethasone and its related compounds in pharmacautical preparations.

    PubMed

    Dolowy, Małgorzata; Pyka, Alina

    2014-01-01

    A new simple and rapid TLC-densitometric procedure for the separation and identification of betamethasone and its related substances, betamethasone-17,21-dipropionate, betamethasone-17-valerate, betamethasone-21-valerate and also betamethasone disodium phosphate was developed. One of the chromatographic systems proposed in this study, which has been satisfactory applied in separation of four pairs of examined compounds was silica gel 60F254 (E. Merck, Art. 1.05554) and a mixture containing chloroform-methanol-acetic acid (99.5%) in volume composition 28:5:0.5. Densitometric measurements were done using densitometer TLC Scanner 3 at 246 nm. The proposed method was checked in terms of its specificity for the determination of betamethasone-17,21-dipropionate and betamethasone disodium phosphate in commercially available products containing both compounds, separately, as active ingredients. The results showed that the method is suitable for qualitative analysis of betamethasone derivatives in simple and combined pharmaceuticals in various dosage forms e.g., lotion and injection solution. It also can be applied in quality control of pharmaceutical formulations of betamethasone and its related compounds in form of salts and esters. PMID:25745764

  18. Microstructural evolution of austenitic stainless steels irradiated in spectrally tailored experiment in ORR at 400°C

    NASA Astrophysics Data System (ADS)

    Sawai, T.; Maziasz, P. J.; Kanazawa, H.; Hishinuma, A.

    1992-09-01

    Several different heats of austenitic stainless steel, including Japanese-PCA(JPCA), were irradiated in the spectrally tailored ORR experiment at 400°C to 7.4 dpa. The levels of helium generated were 155 appm for JPCA (16Ni, 30 wppm B) and 102 appm for standard type 316 steel (13Ni). The mean He: dpa ratio throughout the irradiation falls between 15 and 20 appm He/dpa, which is close to the He/dpa values expected for fusion. Swelling was measured by transmission electron microscopy and by precision immersion densitometry. All the CW alloys showed swelling that was at or below the detection limit of the densitometer (0.1%). No measurable swelling was detected in the SA JPCA alloy, while the highest value of 0.8% was observed in the SA high-purity alloy. One Ti-modified steel with low C also showed a relatively high swelling value of 0.5%, while standard type 316 steel showed only 0.15% swelling. TEM observation gave consistent but slightly larger values of swelling.

  19. The density and photosensitivity of human rhodopsin in the living retina.

    PubMed

    Alpern, M; Pugh, E N

    1974-03-01

    1. The visual pigment in a 5 degrees circular patch of the living human retina 18 degrees temporal from the fovea was studied with the Rushton retinal densitometer. The measuring light (570 nm) was selected to obviate artifacts from colour photoproducts.2. The action spectrum of a 10% bleach agrees well with the action spectrum at absolute threshold for the same patch of retina. The quantized C.I.E. scotopic spectral sensitivity curve is a good description of both spectra. Therefore, the visual pigment studied must be human rhodopsin.3. Its density has been estimated in five different ways. The results are in reasonable agreement. The optical density of human rhodopsin in vivo is about 0.35 (common logarithmic units) at its gamma(max.)4. The photosensitivity of human rhodopsin in vivo was determined by studying its rate of bleaching in response to steps of monochromatic light exposed to the dark adapted eye, by measuring the amount bleached in the steady state by monochromatic lights as well as the amount bleached by 10 sec flashes of white light.5. The results obtained by the different methods are in good agreement with each other and with previous estimates made by others using white light.6. The photosensitivity of human rhodopsin in vivo [epsilongamma(max) = 62,000 to 120,000 l./cm mole] is much higher than expected from in vitro measurements. PMID:4825455

  20. X-ray scatter correction for dual-energy x-ray absorptiometry: compensation of patient's lean/fat composition

    NASA Astrophysics Data System (ADS)

    Dinten, Jean-Marc; Darboux, Michel; Bordy, Thomas; Robert-Coutant, Christine; Gonon, Georges

    2004-05-01

    At CEA-LETI, a DEXA approach for systems using a digital 2D radiographic detector has been developed. It relies on an original X-rays scatter management method, based on a combined use of an analytical model and of scatter calibration data acquired through different thicknesses of Lucite slabs. Since Lucite X-rays interaction properties are equivalent to fat, the approach leads to a scatter flux map representative of a 100% fat region. However, patients" soft tissues are composed of lean and fat. Therefore, the obtained scatter map has to be refined in order to take into account the various fat ratios that can present patients. This refinement consists in establishing a formula relating the fat ratio to the thicknesses of Low and High Energy Lucite slabs leading to same signal level. This proportion is then used to compute, on the basis of X-rays/matter interaction equations, correction factors to apply to Lucite equivalent X-rays scatter map. Influence of fat ratio correction has been evaluated, on a digital 2D bone densitometer, with phantoms composed of a PVC step (simulating bone) and different Lucite/water thicknesses as well as on patients. The results show that our X-rays scatter determination approach can take into account variations of body composition.

  1. Bone mineral content in term infants fed human milk, cow milk-based formula, or soy-based formula.

    PubMed

    Hillman, L S

    1988-07-01

    Bone mineral content (BMC) of the midportion of the humerus was measured with the Norland model 278 bone densitometer in 31 term infants fed human milk (9 inants), cow milk-based formula (11 infants), or soy protein-based formula (11 infants) over the first year of life. Serum and urine minerals, vitamin D, 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D were measured to ensure that intake of minerals and vitamin D was not limiting. Mineralization was similar in all three groups. Over the first year, BMC had a significantly positive slope. However, BMC appeared to increase during the first 4 months, plateau at 6 months, and then resume an increasing pattern. Bone width (BW) increased steadily over the first year; therefore the BMC/BW ratio actually dropped at around 6 months. The BMC was also correlated with body length. "Average density," which was calculated by the formula BMC/pi (BW/2)2, showed a steady decline as age increased. The ratio of BMC to body length over the first year may be an option for comparing individual data to normal data when growth is abnormal. Uncorrected BMC is recommended as a measurement for the infant growing normally; attempts to calculate average density are discouraged. PMID:3392640

  2. Low-cost two-dimensional gel densitometry

    SciTech Connect

    Levenson, R.M.; Maytin, E.V.; Young, D.A.

    1986-11-01

    A major obstacle to full utilization of the powerful technique of two-dimensional (2-D) gel electrophoresis is the expense and complexity of quantifying the results. Using an analog-to-digital converter already present in the widely available Commodore 64 or Commodore 128 microcomputer, the authors have developed a 2-D gel densitometer (GELSCAN) which adds only $20.00 to the cost of the Commodore system (currently around $700.00). The system is designed to work with autoradiograms of 2-D gels. Spots of interest are identified visually and then positioned manually over a light source. A pinhole photoelectric sensor mounted in a hand-held, Plexiglas holder, or mouse, is briefly rubbed over each spot. Maximum density of the spot is determined and its value is converted to counts per minute via an internal calibration curve which corrects for the nonlinear response of film to radiation. Local spot backgrounds can be subtracted and values can be normalized between gels to adjust for variation in amount of radioactivity applied or in exposure time. Reproducibility is excellent and the technique has some practical as well as theoretical advantages over other more complicated approaches to 2-D gel densitometry. In addition, the GELSCAN system can also be used for scanning individual bands in 1-D gels, quantitation of dot-blot autoradiograms and other tasks involving transmission densitometry.

  3. Model of Close Packing for Determination of the Major Characteristics of the Liquid Dispersions Components

    PubMed Central

    Kolikov, Kiril Hristov; Hristozov, Dimo Donchev; Koleva, Radka Paskova; Krustev, Georgi Aleksandrov

    2014-01-01

    We introduce a close packing model of the particles from the disperse phase of a liquid dispersion. With this model, we find the sediment volumes, the emergent, and the bound dispersion medium. We formulate a new approach for determining the equivalent radii of the particles from the sediment and the emergent (different from the Stokes method). We also describe an easy manner to apply algebraic method for determining the average volumetric mass densities of the ultimate sediment and emergent, as well as the free dispersion medium (without using any pycnometers or densitometers). The masses of the different components and the density of the dispersion phase in the investigated liquid dispersion are also determined by means of the established densities. We introduce for the first time a dimensionless scale for numeric characterization and therefore an index for predicting the sedimentation stability of liquid dispersions in case of straight and/or reverse sedimentation. We also find the quantity of the pure substance (without pouring out or drying) in the dispersion phase of the liquid dispersions. PMID:25136673

  4. PDS SHRINK. PDS SHRINK

    SciTech Connect

    Phillion, D.

    1993-09-01

    This code enables one to display, take line-outs on, and perform various transformations on an image created by an array of integer*2 data. Uncompressed eight-bit TIFF files created on either the Macintosh or the IBM PC may also be read in and converted to a 16 bit signed integer image. This code is designed to handle all the formats used for PDS (photo-densitometer) files at the Lawrence Livermore National Laboratory. These formats are all explained by the application code. The image may be zoomed infinitely and the gray scale mapping can be easily changed. Line-outs may be horizontal or vertical with arbitrary width, angled with arbitrary end points, or taken along any path. This code is usually used to examine spectrograph data. Spectral lines may be identified and a polynomial fit from position to wavelength may be found. The image array can be remapped so that the pixels all have the same change of lambda width. It is not necessary to do this, however. Lineouts may be printed, saved as Cricket tab-delimited files, or saved as PICT2 files. The plots may be linear, semilog, or logarithmic with nice values and proper scientific notation. Typically, spectral lines are curved.

  5. PDS SHRINK. PDS SHRINK

    SciTech Connect

    Phillion, D.

    1991-12-15

    This code enables one to display, take line-outs on, and perform various transformations on an image created by an array of integer*2 data. Uncompressed eight-bit TIFF files created on either the Macintosh or the IBM PC may also be read in and converted to a 16 bit signed integer image. This code is designed to handle all the formats used for PDS (photo-densitometer) files at the Lawrence Livermore National Laboratory. These formats are all explained by the application code. The image may be zoomed infinitely and the gray scale mapping can be easily changed. Line-outs may be horizontal or vertical with arbitrary width, angled with arbitrary end points, or taken along any path. This code is usually used to examine spectrograph data. Spectral lines may be identified and a polynomial fit from position to wavelength may be found. The image array can be remapped so that the pixels all have the same change of lambda width. It is not necessary to do this, however. Lineouts may be printed, saved as Cricket tab-delimited files, or saved as PICT2 files. The plots may be linear, semilog, or logarithmic with nice values and proper scientific notation. Typically, spectral lines are curved.

  6. PDS SHRINK

    SciTech Connect

    Phillion, D. )

    1991-12-15

    This code enables one to display, take line-outs on, and perform various transformations on an image created by an array of integer*2 data. Uncompressed eight-bit TIFF files created on either the Macintosh or the IBM PC may also be read in and converted to a 16 bit signed integer image. This code is designed to handle all the formates used for PDS (photo-densitometer) files at the Lawrence Livermore National Laboratory. These formats are all explained by the application code. The image may be zoomed infinitely and the gray scale mapping can be easily changed. Line-outs may be horizontal or vertical with arbitrary width, angled with arbitrary end points, or taken along any path. This code is usually used to examine spectrograph data. Spectral lines may be identified and a polynomial fit from position to wavelength may be found. The image array can be remapped so that the pixels all have the same change of lambda width. It is not necessary to do this, however. Lineouts may be printed, saved as Cricket tab-delimited files, or saved as PICT2 files. The plots may be linear, semilog, or logarithmic with nice values and proper scientific notation. Typically, spectral lines are curved. By identifying points on these lines and fitting their shapes by polyn.

  7. Fabric dependence of wave propagation in anisotropic porous media

    PubMed Central

    Cowin, Stephen C.; Cardoso, Luis

    2012-01-01

    Current diagnosis of bone loss and osteoporosis is based on the measurement of the Bone Mineral Density (BMD) or the apparent mass density. Unfortunately, in most clinical ultrasound densitometers: 1) measurements are often performed in a single anatomical direction, 2) only the first wave arriving to the ultrasound probe is characterized, and 3) the analysis of bone status is based on empirical relationships between measurable quantities such as Speed of Sound (SOS) and Broadband Ultrasound Attenuation (BUA) and the density of the porous medium. However, the existence of a second wave in cancellous bone has been reported, which is an unequivocal signature of poroelastic media, as predicted by Biot’s poroelastic wave propagation theory. In this paper the governing equations for wave motion in the linear theory of anisotropic poroelastic materials are developed and extended to include the dependence of the constitutive relations upon fabric - a quantitative stereological measure of the degree of structural anisotropy in the pore architecture of a porous medium. This fabric-dependent anisotropic poroelastic approach is a theoretical framework to describe the microarchitectural-dependent relationship between measurable wave properties and the elastic constants of trabecular bone, and thus represents an alternative for bone quality assessment beyond BMD alone. PMID:20461539

  8. Densitometric analysis of Western blot (immunoblot) assays for human immunodeficiency virus antibodies and correlation with clinical status.

    PubMed Central

    Schmidt, G; Amiraian, K; Frey, H; Stevens, R W; Berns, D S

    1987-01-01

    Western blot assays for antibodies directed against components of human immunodeficiency virus (HIV) associated with acquired immunodeficiency syndrome (AIDS) were examined with a densitometer and integrator. Antibody responses to seven HIV proteins were determined from the areas under the peaks of bands on blots from 430 seropositive individuals. Antibody responses corresponded qualitatively and quantitatively with clinical status. The Western blot assays examined were done on single specimens from individuals in one of four clinical states: asymptomatic with no risk factor identified, asymptomatic with risk factor(s) identified, AIDS-related complex, and AIDS. The ratios of gp41 antibody to p24 antibody and of gp41 antibody to total HIV antibodies increased, and the number of total HIV antibodies decreased progressively in these populations. Parameters were assigned to characterize the typical response found in AIDS: gp41 antibody/p24 antibody ratio, greater than or equal to 2.0; gp41 antibody/total HIV antibodies ratio, greater than or equal to 0.30; and number of total HIV antibodies, less than or equal to 25.0 signal units. Parameter match increased with progression of clinical status. These parameters were applied in a brief follow-up study of 34 HIV-infected asymptomatic individuals who developed AIDS-related complex or AIDS. Initial specimens showed a stronger correlation than our population data base had predicted, suggesting that the parameters have prognostic value. Densitometric analysis of antibody responses on Western blot assays of single or serial specimens should prove useful to physicians in staging and monitoring HIV-infected individuals and in predicting which individuals will progress to AIDS. Images PMID:2444624

  9. LOFT Monthly Progress Report for November 1980

    SciTech Connect

    N. C. Kaufman

    1980-12-01

    During November major work efforts were directed towards preparation for Test L3-6/L8-1. These tests, to be run in sequence, will evalute the system effects of primary coolant pump operation during a small break LOCA (L3-6), and are to obtain a partial core uncovery to aid in the planning and conduct of future core uncovery experiments (L8-1). Plant modifications in preparation for the December test included installation of a new PC-3 gamma densitometer to measure the density of fluid coming from the steam generator and the installation of the EPRI Liquid Level Detector system to measure levels of fluid during the core uncovery experiment. Other key efforts concerned planning for test conduct and safety analysis. On November 6 and 7 the LOFT Review Group met in Idaho Falls to evaluate the activities on LOFT since its last meeting in February. Future test plans, budgets, the man-machine (AOC) program, and various other topics presented by LOFT personnel and consultants were discussed. Several suggestions were presented by those in attendance. These comments were directed to the areas of test scheduling and the kinds of tests to be run as well as how LOFT could better communicate with utilities and vendors to transmit information to the general nuclear power industry. Overall costs are in good agreement with current budgets and authorized funding levels. In the areas of fuel design and analysis, a temporary overrun will be shown for the first few months of the fiscal year. This overrun is due to an Exxon billing received ahead of schedule. A recovery plan has been implemented and actuals are expected to be in agreement with budget by January 1981.

  10. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mengjiao Yu; Ramadan Ahmed; Mark Pickell; Len Volk; Lei Zhou; Zhu Chen; Aimee Washington; Crystal Redden

    2003-09-30

    The Quarter began with installing the new drill pipe, hooking up the new hydraulic power unit, completing the pipe rotation system (Task 4 has been completed), and making the SWACO choke operational. Detailed design and procurement work is proceeding on a system to elevate the drill-string section. The prototype Foam Generator Cell has been completed by Temco and delivered. Work is currently underway to calibrate the system. Literature review and preliminary model development for cuttings transportation with polymer foam under EPET conditions are in progress. Preparations for preliminary cuttings transport experiments with polymer foam have been completed. Two nuclear densitometers were re-calibrated. Drill pipe rotation system was tested up to 250 RPM. Water flow tests were conducted while rotating the drill pipe up to 100 RPM. The accuracy of weight measurements for cuttings in the annulus was evaluated. Additional modifications of the cuttings collection system are being considered in order to obtain the desired accurate measurement of cuttings weight in the annular test section. Cutting transport experiments with aerated fluids are being conducted at EPET, and analyses of the collected data are in progress. The printed circuit board is functioning with acceptable noise level to measure cuttings concentration at static condition using ultrasonic method. We were able to conduct several tests using a standard low pass filter to eliminate high frequency noise. We tested to verify that we can distinguish between different depths of sand in a static bed of sand. We tested with water, air and a mix of the two mediums. Major modifications to the DTF have almost been completed. A stop-flow cell is being designed for the DTF, the ACTF and Foam Generator/Viscometer which will allow us to capture bubble images without the need for ultra fast shutter speeds or microsecond flash system.

  11. Evaluation of GAFCHROMIC registered EBT film for CyberKnife registered dosimetry

    SciTech Connect

    Wilcox, Ellen E.; Daskalov, George M.

    2007-06-15

    External beam therapy (EBT) GAFCHROMIC registered film is evaluated for dosimetry and characterization of the CyberKnife registered radiation beams. Percentage depth doses, lateral beam profiles, and output factors are measured in solid water using EBT GAFCHROMIC registered film (International Specialty Products, Wayne, NJ) for the 6 MV radiation beams of diameter 5 to 60 mm produced by the CyberKnife registered (Accuray, Sunnyvale, CA). The data are compared to those measured with the PTW 60008 diode and the Wellhofer CC01 ion chamber in water. For the small radiation field sizes used in stereotactic radiosurgery, lateral electronic disequilibrium and steep dose gradients exist in a large portion of these fields, requiring the use of high-resolution measurement techniques. For small beams, the detector size approaches the dimensions of the beam and adversely affects measurement accuracy in regions where the gradient varies across the detector. When film is the detector, the scanning system is usually the resolution-limiting component. Radiographic films based upon silver halide (AgH) emulsions are widely used for relative dosimetry of external radiation treatment beams in the megavoltage energy range, because of their good spatial resolution and capability to provide integrated dosimetry over two dimensions. Film dosimetry, however, has drawbacks due to its steep energy dependence at low photon energies as well as film processor and densitometer artifacts. EBT radiochromic film, introduced in 2004 specifically for IMRT dosimetry, may be a detector of choice for the characterization of small radiosurgical beams, because of its near-tissue equivalence, radiation beam energy independence, high spatial resolution, and self developing properties. For radiation beam sizes greater than 10 mm, the film measurements were identical to those of the diode and ion chamber. For the smaller beam diameters of 7.5 and 5 mm, however, there were differences in the data measured with

  12. Microvascular flow distribution and transcapillary diffusion at the forefoot in patients with peripheral ischemia.

    PubMed

    Jünger, M; Frey-Schnewlin, G; Bollinger, A

    1989-02-01

    Transcapillary diffusion of Na-fluorescein injected by the intravenous route was measured by a videomicroscopy system in the skin of the dorsum of the forefoot in healthy controls (n = 21) and in patients with moderate (n = 35) and severe (n = 29) ischemia secondary to lower extremity arterial occlusive disease. Systolic ankle blood pressure and transcutaneous PO2 at the forefoot were significantly decreased in both groups of patients according to the severity of ischemic disease (p less than 0.001). The difference of the mean filling times between the first and last capillaries was used as a parameter for inhomogenous microvascular perfusion. It was significantly increased in moderate and severe ischemia (p less than 0.05). Transcapillary diffusion measured with a large window densitometer in a skin area of 2.8 mm2 was significantly enhanced in both groups of patients. The increase was more pronounced in the patients with severe ischemia (p less than 0.001) than in those with moderate ischemia (p less than 0.05). Among the patients with severe ischemia the diabetics exhibited significantly higher mean values of pericapillary fluorescence light intensity than the non-diabetics (p less than 0.001). At high magnification (550 times) distinct sites of increased transcapillary diffusion were detected in both groups of patients. They were most often localized at the apex of the capillary loops ("candle light phenomenon") and were more frequent in patients with severe than with moderate ischemia. In conclusion microvascular blood flow distribution is inhomogeneous and transcapillary diffusion increases at the level of single capillaries and skin areas in patients with moderate and especially severe foot ischemia. PMID:2722409

  13. Changes in Major Peanut Allergens Under Different pH Conditions.

    PubMed

    Kim, Jihyun; Lee, Jeongok; Seo, Won Hee; Han, Youngshin; Ahn, Kangmo; Lee, Sang-Il

    2012-05-01

    Regional dietary habits and cooking methods affect the prevalence of specific food allergies; therefore, we determined the effects of various pH conditions on major peanut allergens. Peanut kernels were soaked overnight in commercial vinegar (pH 2.3) or acetic acid solutions at pH 1.0, 3.0, or 5.0. Protein extracts from the sera of seven patients with peanut-specific IgE levels >15 kU(A)/L were analyzed by SDS-PAGE and immunolabeling. A densitometer was used to quantify and compare the allergenicity of each protein. The density of Ara h 1 was reduced by treatment with pH 1.0, 3.0, or 5.0 acetic acid, or commercial vinegar. Ara h 2 remained largely unchanged after treatment with pH 5.0 acetic acid, and was decreased following treatment with pH 1.0, 2.3, or 3.0 acetic acid. Ara h 3 and Ara h 6 appeared as a thick band after treatment with pH 1.0 acetic acid and commercial vinegar. IgE-binding intensities to Ara h 1, Ara h 2, and Ara h 3 were significantly reduced after treatment with pH 1.0 acetic acid or commercial vinegar. These data suggest that treatment with acetic acid at various pH values affects peanut allergenicity and may explain the low prevalence of peanut allergy in Korea. PMID:22548209

  14. Approach to the Child with Fractures

    PubMed Central

    Boyce, Alison M.

    2011-01-01

    Evaluation of the child with fractures is challenging, as no clear guidelines exist to distinguish traumatic from pathological fractures. Although most fractures in childhood are benign, recurrent fractures may be associated with a wide variety of primary skeletal diseases as well as secondary causes, necessitating a careful history and physical exam to guide the evaluation. There is no “gold standard” for the evaluation and treatment of children with fractures and low bone mineral density (BMD); therefore, the diagnosis of osteoporosis in a pediatric patient should be made using a combination of clinical and radiographic features. Interpretation of bone densitometry in growing patients presents a unique set of challenges because areal BMD measured by dual-energy x-ray absorptiometry depends on multiple dynamic variables. Interpretation of pediatric dual-energy x-ray absorptiometry should be based on Z-scores (sd scores compared to age, sex, and ethnicity-matched controls), using normative databases specific to the brand of densitometer and the patient population. Given the skeleton's ability to recover from low BMD through modeling and remodeling, optimizing management of underlying conditions leading to bone fragility is the initial step. Conservative measures including calcium and vitamin D supplementation and weight-bearing physical activity are important interventions that should not be overlooked. The use of bisphosphonates in children and adolescents is controversial due to lack of long-term efficacy and safety data and should be limited to clinical trials and compassionate therapy in children with significantly compromised quality of life. Close monitoring is required, and further study is necessary to assess their long-term safety and efficacy in children. PMID:21734001

  15. Proteins of the rat prostate. II. Synthesis of new proteins in the ventral lobe during castration-induced regression

    SciTech Connect

    Lee, C.; Sensibar, J.A.

    1987-10-01

    Ventral prostates from adult Sprague-Dawley rats at different days postcastration were cut into one to two mm.3 pieces and incubated in medium containing S-35-methionine (100 uCi/ml.) at 37 C under 95% oxygen and 5% carbon dioxide for four hours. The incubated tissues were subjected to two-dimensional electrophoresis and radiofluorography. Over 100 spots were developed in the fluorograms. Three groups of spots, representing cytoskeletal proteins, androgen-dependent proteins and castration-induced proteins, were further evaluated by a computer-based densitometer. The level of densitometry absorption is proportional to the amount of radioactivity in each spot. The synthesis of cytoskeletal proteins, such as actin and tropomyosin, were relatively constant throughout the course of prostatic regression. The rate of synthesis of androgen-dependent proteins declined rapidly from a high level of synthesis before castration to a non-detectable level by Day 3 postcastration. However, three proteins, which were either not synthesized (spot G and spot H) or synthesized at a very low level (spot I) before castration, were the major proteins synthesized by the prostate during early stages of its regression. The rate of synthesis of these proteins reached a peak by Day 4 postcastration, declined rapidly and remained at a low level thereafter. The respective molecular weights and isoelectric points for these three proteins were 33 Kd and 7.2 for spot G, 38 Kd and 5.3 for spot H and 64 Kd and 6.0 for spot I. Previous findings showed that prostatic regression in rats was associated with a surge of activities in proteolytic enzymes which peaked five to six days postcastration.

  16. Airlift bioreactors: Experimental and theoretical analysis or two-phase hydrodynamics

    SciTech Connect

    Young, M.A.

    1989-01-01

    Local two-phase flow measurements were obtained in a pilot-scale, external loop airlift bioreactor. The gas-liquid system was air and water; the gas phase was not recirculated. Sparging rates ranged from 1.0-8.0 cm/s, using a multiorifice, ring sparger. The axial dependence of the cross sectionally averaged gas volume fraction was determined using a track-mounted gamma densitometer. Hot-film anemometry was used to measure the radial and azimuthal dependence of the liquid velocity and turbulence for two axial riser locations. The same spatial dependence was ascertained for the gas velocity and volume fraction using resistivity probe techniques. The axial distribution of liquid phase pressure was measured with precision inclined manometers. The axial dependence of the void fraction was found to be modest. The radial dependence of the gas and liquid velocities and the void fraction was substantial, especially near the sparger. Local property changes with azimuthal position were small, and the flow may be characterized as being azimuthally symmetric. The developing flow effects were pronounced, as evidenced by the distinct changes in the radial profiles of fluid flow properties with axial position. Under certain operating conditions, liquid acceleration effects near the sparger resulted in greatly reduced slip velocities. For the two-phase riser flow, a model was developed directly from the point equations of continuity and motion, resulting in a differential, two-fluid form. Macroscopic mechanical energy balance equations were used to describe the flow in the gas-liquid separator and the downcomer. The model incorporates empirical parameters for the frictional effects only. The developing two-phase flow characteristic of airlift risers was observed to create large frictional effects at the wall.

  17. Increased amyloidogenic secretion in cerebellar granule cells undergoing apoptosis

    PubMed Central

    Galli, Cinzia; Piccini, Alessandra; Ciotti, Maria Teresa; Castellani, Loriana; Calissano, Pietro; Zaccheo, Damiano; Tabaton, Massimo

    1998-01-01

    Some clues suggest that neuronal damage induces a secondary change of amyloid β protein (Aβ) metabolism. We investigated this possibility by analyzing the secretion of Aβ and processing of its precursor protein (amyloid precursor protein, APP) in an in vitro model of neuronal apoptosis. Primary cultures of rat cerebellar granule neurons were metabolically labeled with [35S]methionine. Apoptosis was induced by shifting extracellular KCl concentration from 25 mM to 5 mM for 6 h. Control and apoptotic neurons were then subjected to depolarization-stimulated secretion. Constitutive and stimulated secretion media and cell lysates were immunoprecipitated with antibodies recognizing regions of Aβ, full-length APP, α- and β-APP secreted forms. Immunoprecipitated proteins were separated by SDS/PAGE and quantitated with a PhosphorImager densitometer. Although intracellular full-length APP was not significantly changed after apoptosis, the monomeric and oligomeric forms of 4-kDa Aβ were 3-fold higher in depolarization-stimulated secretion compared with control neurons. Such increments were paralleled by a corresponding increase of the β-APPs/α-APPs ratio in apoptotic secretion. Immunofluorescence studies performed with an antibody recognizing an epitope located in the Aβ sequence showed that the Aβ signal observed in the cytoplasm and in the Golgi apparatus of control neurons is uniformly redistributed in the condensed cytoplasm of apoptotic cells. These studies indicate that neuronal apoptosis is associated with a significant increase of metabolic products derived from β-secretase cleavage and suggest that an overproduction of Aβ may be the consequence of neuronal damage from various causes. PMID:9448317

  18. Radiopacity of different shades of resin-based restorative materials compared to human and bovine teeth.

    PubMed

    Pekkan, Gurel; Ozcan, Mutlu

    2012-01-01

    This study evaluated the radiopacity of different shades of resin-based restorative materials and compared the results to human and bovine dental hard tissues. Disk specimens 6 mm in diameter and 1 mm thick (N = 220, n = 10) were prepared from the following restorative materials: · eight shades of nanofilled composite (Aelite Aesthetic Enamel), · seven shades of nanohybrid composite (Grandio Universal), · six shades of photopolymerized polyacid modified compomer (Glasiosite), and · one shade of hybrid composite (X-tra fil U). Human canine dentin (n = 10), bovine enamel (n = 10), and an aluminum (Al) step wedge were used as references. The optical density values of each material were measured from radiographic images using a transmission densitometer. Al step wedge thickness and optical density values were plotted, and equivalent Al thickness (eq Al) values were determined for radiopacity measurements of each material. The data were analyzed using a non-parametric one-way ANOVA (Kruskal-Wallis), and multiple comparisons were made with a Student-Newman-Keuls post hoc test (a = 0.05). Different shades of resin-based restorative materials tested did not reveal statistically significant differences within each material group (p > 0.05). Radiopacity values of the resin-based restorative materials investigated varied depending on their types; however, within different shades of one material type, radiopacity values were comparable. Every shade of nanocomposite material other than Aelite Aesthetic Enamel Incisal LT Gray showed comparable radiopacity to human dentin. Other materials tested demonstrated higher radiopacity compared to human dentin and bovine enamel. PMID:22782058

  19. Rib fractures in chronic alcoholic men: Relationship with feeding habits, social problems, malnutrition, bone alterations, and liver dysfunction.

    PubMed

    González-Reimers, Emilio; García-Valdecasas-Campelo, Elena; Santolaria-Fernández, Francisco; Milena-Abril, Antonio; Rodríguez-Rodríguez, Eva; Martínez-Riera, Antonio; Pérez-Ramírez, Alina; Alemán-Valls, María Remedios

    2005-10-01

    Rib fractures are common in alcoholics. This high prevalence might be due to ethanol-associated malnutrition, bone disease, liver dysfunction, or the peculiar lifestyle of the alcoholic with frequent trauma and altercations. In this study we try to discern the role of these factors on rib fracture (assessed on a plain thoracic X-ray film) in 81 consecutive alcoholic patients, 25 of them cirrhotics. Serum albumin, prothrombin aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), gamma-glutamyl transpeptidase, C-terminal cross-linking telopeptide of type 1 collagen, osteocalcin, insulin growth factor 1, 1,25-dihydroxyvitamin D, parathyroid hormone, estradiol, free testosterone, and corticosterone were measured, and the patients also underwent assessment of bone mineral density by a HOLOGIC QDR-2000 bone densitometer (Waltham, MA, USA). Body mass index, triceps skinfold, and brachial perimeter were also determined, and the patients and their families were asked about tobacco consumption, social and familial links, consumption of ethanol by other members of the family, kind of job, and feeding habits. Forty-two male nondrinker sanitary workers of similar age served as controls. Forty of the 81 patients showed rib fractures. There was a statistically significant association between rib fractures and disruption of social and familial links, irregular feeding habits (in bars or pubs, not at home), ethanol consumption by close relatives, and intensity of tobacco consumption, but not between rib fractures and liver function tests, nutritional parameters, or bone mineral density, besides a nearly significant trend (p = .053) with the presence of osteopenia at the femoral neck. Patients with major withdrawal symptoms at admission also presented more frequent rib fractures. We conclude that rib fractures in alcoholics are related to the peculiar lifestyle of these patients rather than to bone alterations, liver dysfunction, or nutritional status. PMID:16584975

  20. Characterization of coal-derived liquids and other fossil-fuel-related materials employing mass spectrometry. Final report, September 30, 1976-September 29, 1980

    SciTech Connect

    Scheppele, S E

    1982-05-01

    A document was prepared which assessed the state-of-the art in the mass spectrometric characterization of fossil fuel materials and the relevance of these data to the fossil fuel industry. A Kratos DS50 SM data system was successfully interfaced to a CEC 21-110B mass spectrometer. Communications between the NOVA 3/12 computer in the data system and the OSU central computer were established. A Grant Comparator/Microdensitometer was acquired and made operational. Plans were developed and hardware acquired for interfacing the densitometer to the NOVA 3/12 computer. A quartz direct introduction probe was acquired for the CEC 21-110B. A temperature controller for the probe was acquired and interfaced to the slow speed ADC on the auxillary board in the data system/mass spectrometer interface. The combined FI/EI source was modified to operate in the FD mode and an apparatus was fabricated for conditioning FD emitters. A CSI supergrater 3 was interfaced to the PE 3920 gas chromatograph. The upgraded facility was used to develop mass spectrometric methods for the characterization of fossil fuel materials and to apply methods to the characterization of these materials. Activities included: (1) initial development of field-ionization mass spectrometry for the characterization of saturated hydrocarbons, (2) computerization of the technique of probe microdistillation/mass spectrometry, (3) initation of the development of a new method for the computer assisted assignment of formulas to ion masses, (4) characterization of neutral fractions from a hydrotreated tar-sands oil, and (5) characterization of coal-derived oils and asphaltenes.

  1. Quantitative TLC-Image Analysis of Urinary Creatinine Using Iodine Staining and RGB Values.

    PubMed

    Kerr, Emily; West, Caroline; Kradtap Hartwell, Supaporn

    2016-04-01

    Digital image analysis of the separation results of colorless analytes on thin-layer chromatography (TLC) plates usually involves using specially tailored software to analyze the images generated from either a UV scanner or UV lamp station with a digital camera or a densitometer. Here, a low-cost alternative setup for quantitative TLC-digital image analysis is demonstrated using a universal staining reagent (iodine vapor), an office scanner and a commonly available software (Microsoft Paint) for analysis of red, green and blue colors (RGB values). Urinary creatinine is used as a model analyte to represent a sample in complicated biological matrices. Separation was carried out on a silica gel plate using a butanol-NH4OH-H2O (40 : 10 : 50, v/v) mobile phase with a 6-cm solvent front. It is important that the TLC plate be stained evenly and with sufficient staining time. Staining the TLC plate in a 23.4 × 18.8 × 6.8 cm chamber containing about 70 g iodine crystals yielded comparable results for the staining times of 30-60 min. The Green value offered the best results in the linear working range (0.0810-0.9260 mg/mL) and precision (2.03% RSD, n = 10). The detection limit was found to be 0.24 µg per 3 µL spot. Urinary creatinine concentrations determined by TLC-digital image analysis using the green value calibration graph agree well with results obtained from high-pressure liquid chromatography (HPLC). PMID:26657734

  2. Application of the Minkowski-functionals for automated pattern classification of breast parenchyma depicted by digital mammography

    NASA Astrophysics Data System (ADS)

    Boehm, Holger F.; Fischer, Tanja; Riosk, Dororthea; Britsch, Stefanie; Reiser, Maximilian

    2008-03-01

    With an estimated life-time-risk of about 10%, breast cancer is the most common cancer among women in western societies. Extensive mammography-screening programs have been implemented for diagnosis of the disease at an early stage. Several algorithms for computer-aided detection (CAD) have been proposed to help radiologists manage the increasing number of mammographic image-data and identify new cases of cancer. However, a major issue with most CAD-solutions is the fact that performance strongly depends on the structure and density of the breast tissue. Prior information about the global tissue quality in a patient would be helpful for selecting the most effective CAD-approach in order to increase the sensitivity of lesion-detection. In our study, we propose an automated method for textural evaluation of digital mammograms using the Minkowski Functionals in 2D. 80 mammograms are consensus-classified by two experienced readers as fibrosis, involution/atrophy, or normal. For each case, the topology of graylevel distribution is evaluated within a retromamillary image-section of 512 x 512 pixels. In addition, we obtain parameters from the graylevel-histogram (20th percentile, median and mean graylevel intensity). As a result, correct classification of the mammograms based on the densitometic parameters is achieved in between 38 and 48%, whereas topological analysis increases the rate to 83%. The findings demonstrate the effectiveness of the proposed algorithm. Compared to features obtained from graylevel histograms and comparable studies, we draw the conclusion that the presented method performs equally good or better. Our future work will be focused on the characterization of the mammographic tissue according to the Breast Imaging Reporting and Data System (BI-RADS). Moreover, other databases will be tested for an in-depth evaluation of the efficiency of our proposal.

  3. Subcutaneous administration of insulin-like growth factor (IGF)-II/IGF binding protein-2 complex stimulates bone formation and prevents loss of bone mineral density in a rat model of disuse osteoporosis

    NASA Technical Reports Server (NTRS)

    Conover, Cheryl A.; Johnstone, Edward W.; Turner, Russell T.; Evans, Glenda L.; John Ballard, F. John; Doran, Patrick M.; Khosla, Sundeep

    2002-01-01

    Elevated serum levels of insulin-like growth factor binding protein-2 (IGFBP-2) and a precursor form of IGF-II are associated with marked increases in bone formation and skeletal mass in patients with hepatitis C-associated osteosclerosis. In vitro studies indicate that IGF-II in complex with IGFBP-2 has high affinity for bone matrix and is able to stimulate osteoblast proliferation. The purpose of this study was to determine the ability of the IGF-II/IGFBP-2 complex to increase bone mass in vivo. Osteopenia of the femur was induced by unilateral sciatic neurectomy in rats. At the time of surgery, 14-day osmotic minipumps containing vehicle or 2 microg IGF-II+9 microg IGFBP-2/100g body weight/day were implanted subcutaneously in the neck. Bone mineral density (BMD) measurements were taken the day of surgery and 14 days later using a PIXImus small animal densitometer. Neurectomy of the right hindlimb resulted in a 9% decrease in right femur BMD (P<0.05 vs. baseline). This loss in BMD was completely prevented by treatment with IGF-II/IGFBP-2. On the control limb, there was no loss of BMD over the 14 days and IGF-II/IGFBP-2 treatment resulted in a 9% increase in left femur BMD (P<0.05). Bone histomorphometry indicated increases in endocortical and cancellous bone formation rates and in trabecular thickness. These results demonstrate that short-term administration of the IGF-II/IGFBP-2 complex can prevent loss of BMD associated with disuse osteoporosis and stimulate bone formation in adult rats. Furthermore, they provide proof of concept for a novel anabolic approach to increasing bone mass in humans with osteoporosis.

  4. Assessment of RELAP5-3D{copyright} using data from two-dimensional RPI flow tests

    SciTech Connect

    Davis, C.B.

    1998-07-01

    The capability of the RELAP5-3D{copyright} computer code to perform multi-dimensional thermal-hydraulic analysis was assessed using data from steady-state flow tests conducted at Rensselaer Polytechnic Institute (RPI). The RPI data were taken in a two-dimensional test section in a low-pressure air/water loop. The test section consisted of a thin vertical channel that simulated a two-dimensional slice through the core of a pressurized water reactor. Single-phase and two-phase flows were supplied to the test section in an asymmetric manner to generate a two-dimensional flow field. A traversing gamma densitometer was used to measure void fraction at many locations in the test section. High speed photographs provided information on the flow patterns and flow regimes. The RPI test section was modeled using the multi-dimensional component in RELAP5-3D Version BF06. Calculations of three RPI experiments were performed. The flow regimes predicted by the base code were in poor agreement with those observed in the tests. The two-phase regions were observed to be in the bubbly and slug flow regimes in the test. However, nearly all of the junctions in the horizontal direction were calculated to be in the stratified flow regime because of the relatively low velocities in that direction. As a result, the void fraction predictions were also in poor agreement with the measured values. Significantly improved results were obtained in sensitivity calculations with a modified version of the code that prevented the horizontal junctions from entering the stratified flow regime. These results indicate that the code`s logic in the determination of flow regimes in a multi-dimensional component must be improved. The results of the sensitivity calculations also indicate that RELAP5-3D will provide a significant multi-dimensional hydraulic analysis capability once the flow regime prediction is improved.

  5. Monitoring gas retention and slurry transport during the transfer of waste from Tank 241-C-106 to Tank 241-AY-102

    SciTech Connect

    Stewart, C.W.; Erian, F.F.; Meyer, P.A.

    1997-07-01

    The retained gas volume can be estimated by several methods. All of these methods have significant uncertainties, but together they form a preponderance of evidence that describes the gas retention behavior of the tank. The methods are (1) an increase in nonconvective layer thickness; (2) a waste surface level rise (surface level effect [SLE] model); (3) the barometric pressure effect (BPE model); (4) direct void measurement; and (5) the consequences of the transfer process. The nonconvective layer thickness can be determined with sufficient accuracy to describe the overall waste configuration by means of temperature profiles or densitometer indications. However, the presence of a nonconvective layer does not necessarily indicate significant gas retention, and small changes in layer thickness that could quantify gas retention cannot be detected reliably with the methods available. The primary value of this measurement is in establishing the actual {open_quotes}fluffing factor{close_quotes} for thermal calculations. Surface level rise is not a useful measure of gas retention in Tank 241-C-106 (C-106) since the waste level fluctuates with regular makeup water additions. In Tank 241-AY-102 (AY-102) with the existing ventilation system it should be possible to determine the gas retention rate within 30-60% uncertainty from the surface level rise, should a significant rise be observed. The planned ventilation system upgrades in AY- 102 will greatly reduce the exhaust flow and the headspace humidity, and the evaporation rate should be significantly lower when transfers begin. This could reduce the uncertainty in gas retention rate estimates to around {+-} 10%.

  6. Effect of varying processing solution temperature on radiographic contrast and relative film speed of dental film.

    PubMed

    Matthee, M J; Becker, P J; Seeliger, J E

    1990-12-01

    The aim of this study was to determine the effect of a stepwise rise in temperature on three film types processed in six different processing solutions and to identify the combinations of film, solution and temperature which produced the best results in terms of radiographic contrast and relative film speed. The film types were Agfa Dentus M2, Flow X-ray and Kodak Ultra Speed while the processing solutions were Agfa, Dürr, EBX, Kolchem, MEMS and Pro-tech. An aluminium step-wedge was exposed under standardised conditions. Processing was carried out in a Dürr 245L automatic processor with variable temperature settings from 25 degrees to 35 degrees C. Unexposed films were processed at each temperature setting to determine the base plus fog values. Densitometric readings were taken using a digital densitometer, and the base plug fog values subtracted from each reading. Radiographic contrast and relative film speed were calculated and the data obtained subjected to statistical analysis using Duncan's Multiple Range Test. It could be concluded that, as the processing solution temperature rose from 25 degrees C to 35 degrees C, both radiographic contrast and relative film speed increased. The highest radiographic contrast was obtained by Agfa film in Kolchem solution at 35 degrees C, while Kodak Ultra Speed film in MEMS solution at 35 degrees C gave the highest relative film speed. An acceptable base plus fog level of 0.25 was obtained in the case of Agfa film in combination with Agfa, Dürr and Pro-tech solutions and Flow X-ray film with Dürr solutions. All the other combinations produced a base plug fog level higher than 0.25. PMID:2098942

  7. Scanner-based image quality measurement system for automated analysis of EP output

    NASA Astrophysics Data System (ADS)

    Kipman, Yair; Mehta, Prashant; Johnson, Kate

    2003-12-01

    Inspection of electrophotographic print cartridge quality and compatibility requires analysis of hundreds of pages on a wide population of printers and copiers. Although print quality inspection is often achieved through the use of anchor prints and densitometry, more comprehensive analysis and quantitative data is desired for performance tracking, benchmarking and failure mode analysis. Image quality measurement systems range in price and performance, image capture paths and levels of automation. In order to address the requirements of a specific application, careful consideration was made to print volume, budgetary limits, and the scope of the desired image quality measurements. A flatbed scanner-based image quality measurement system was selected to support high throughput, maximal automation, and sufficient flexibility for both measurement methods and image sampling rates. Using an automatic document feeder (ADF) for sample management, a half ream of prints can be measured automatically without operator intervention. The system includes optical character recognition (OCR) for automatic determination of target type for measurement suite selection. This capability also enables measurement of mixed stacks of targets since each sample is identified prior to measurement. In addition, OCR is used to read toner ID, machine ID, print count, and other pertinent information regarding the printing conditions and environment. This data is saved to a data file along with the measurement results for complete test documentation. Measurement methods were developed to replace current methods of visual inspection and densitometry. The features that were being analyzed visually could be addressed via standard measurement algorithms. Measurement of density proved to be less simple since the scanner is not a densitometer and anything short of an excellent estimation would be meaningless. In order to address the measurement of density, a transfer curve was built to translate the

  8. The Effect of the Lumbar Vertebral Malpositioning on Bone Mineral Density Measurements of the Lumbar Spine by Dual-Energy X-Ray Absorptiometry.

    PubMed

    Izadyar, Sina; Golbarg, Shima; Takavar, Abbas; Zakariaee, Seyed Salman

    2016-01-01

    A significant discrepancy between the results of previous human and phantoms studies is identified regarding the effects of vertebral positioning on bone mineral density (BMD) measurements. We aimed to evaluate the effects of lumbar vertebral positioning on BMD measurements by dual-energy X-ray absorptiometry in a human cadaveric spine phantom. A spine phantom was designed using L1-L4 vertebrae harvested from a 48-year-old male cadaver without coronal or sagittal deformity. The spine phantom was scanned by DEXXUM T bone densitometer in a constant scanning speed of 30 mm/s and resolution of 1.0 × 1.0 mm. BMD values were measured in a positive and negative lumbar lordosis and kyphosis tilt angles in the sagittal plane, from 0° to 35°, with 7° increments. Also BMD values were measured in axial and lateral rotations with 5° increments. Projectional dual-energy X-ray absorptiometry measurements are significantly affected by positioning of the lumbar spine, more severely affected by kyphotic curvature, but also by axial and lateral rotational scoliosis as well as lordotic curvature. Increasing the severity of lordosis and kyphosis curvatures leads to false reduction of BMD value up to 17.5% and 11.5%, respectively. Increasing the degree of lateral and axial rotational scolioses results in a false decrease in BMD measurements by up to 10.8% and 9.6%, respectively. To achieve the most accurate scanning results, error sources and abnormal positioning should be identified and minimized as much as possible. If not correctable, they should be taken into consideration while interpreting the results. PMID:26778450

  9. Radiopacity of resin-based materials measured in film radiographs and storage phosphor plate (Digora).

    PubMed

    Sabbagh, Joseph; Vreven, José; Leloup, Gaetane

    2004-01-01

    This study compared the radiopacity of 41 resin-based materials using conventional dental x-ray film (Ultraspeed-D) and a digital system (Digora) based on storage phosphor plate technology. For the film-based technique, optical density measurements were carried out using an X-Rite densitometer. Al equivalents (mm) were calculated as described in the literature using a calibration curve of Optical Density versus the thickness of aluminum. Regarding the digital system after exposures of 0.16 and 0.32 seconds, the images were exported to an image processing software (NIH Image Engineering). An approach similar to that used for optical density was used to generate a calibration curve for gray pixel values. Linear correlations were found between the percentage of fillers by weight and x-ray film radiopacity and the Digora system, and the same coefficient of estimation was recorded (r=0.60; p< or = 0.05). A linear correlation was also observed between the conventional x-ray film technique and the Digora system (r=0.93;p< or = 0.05). Using two different exposure times did not affect the radiopacity. Considerable differences were found among materials of the same category. Flowable resin composites were more radiopaque than dentin, while microfine composites were "radiolucent." Most of the available resin-based materials were more radiopaque than enamel. The radiopacity of resin composites depended on their fillers (percentage and type). Using elements with low atomic numbers (Si) resulted in radiolucent materials, while adding elements with high molecular numbers (Ba, Y, Yb), resulted in radiopaque resin composites. Despite the numerous benefits offered by the digital imaging system (low irradiation dose, instant image, image manipulation), the conventional x-ray film technique seems to be more accurate for radiopacity measurements. PMID:15646224

  10. Density Measurement of Molten Alkaline-Earth Fluorides Using Archimedean Dual-Sinker Method

    NASA Astrophysics Data System (ADS)

    Takeda, Osamu; Yanagase, Kei-ichi; Anbo, Yusuke; Aono, Masahiro; Hoshino, Yosuke; Sato, Yuzuru

    2015-11-01

    The densities of molten alkaline-earth fluorides ({MgF}2, {CaF}2, {SrF}2, and {BaF}2) were measured over the temperature range from 1526 K to 1873 K at ambient pressure using an Archimedean dual-sinker densitometer designed and set up by the authors. The volume difference between two sinkers was precisely determined by considering the wetting conditions between tungsten sinkers and water; appropriate experimental techniques were developed. The wetting condition became unstable when the sinkers were being moved for immersion in water, because the sinkers were moved in a direction that increased the contact angle. The wetting condition became stable when the sinkers were pulled up from the water, because the sinkers were moved in a direction that decreased the contact angle. The force exerted by the surface tension was efficiently canceled, and the volume difference became constant when the sinkers were pulled up. In this study, the total uncertainty was about 0.3 % at a maximum. The densities measured at high temperatures showed good linearity, with small scatter, over a wide temperature range. The densities and molar volumes increased in the following order: {MgF}2, {CaF}2, {SrF}2, and {BaF}2. The thermal-expansion coefficients showed anomalous behavior. The large thermal-expansion coefficient of {MgF}2 is attributed to a decrease in the cohesive force as a result of a partial loss of the coulombic force, because of the high charge density.

  11. Use of iQPR-H2O for bone regeneration and its potential in the improvement of osteoporosis

    PubMed Central

    2011-01-01

    Background Current treatments for osteoporosis are associated with various side effects and do not prevent the age-related decrease in osteoblast number. The objective of this study was to evaluate the effects of iQPR-H2O on osteogenesis. Methods Mouse fibroblast NIH3T3 and pre-osteoblastic MC3T3-E1 cells were cultured in medium prepared with iQPR-H2O or unprocessed mineral water (control cells), and proliferation and differentiation were assessed by MTT and alkaline phosphatase assay, respectively. Mineral deposition by the cells was determined using Alizarin red S staining. A mouse model of osteoporosis, ovariectomized SAMP8 mice, was used to evaluate the effects of iQPR-H2O on osteogenesis in vivo. Mice were given either iQPR-H2O or unprocessed mineral water (control group) for four months after which bone mass density (BMD) measurements were made using a bone densitometer and hematoxylin and eosin staining of bone samples. Results NIH3T3 cells grown in medium prepared with iQPR-H2O exhibited significantly greater proliferation. NIH3T3 and MC3T3-E1 cells demonstrated a significant increase in alkaline phosphatase levels in the iQPR-H2O group. MC3T3-E1 cells showed mineralization at day 28. mRNA expression levels of both osteopontin and runt-related transcription factor 2 in MC3T3-E1 cells were higher in the iQPR-H2O group compared with the control group. After four months, significantly greater bone regeneration was evident in ovariectomized SAMP8 mice administered iQPR-H2O as compared with control group. Conclusions iQPR-H2O may reduce the symptoms of osteoporosis by improving osteogenesis. PMID:21981964

  12. Comparison of nuclear magnetic resonance spectroscopy with dual-photon absorptiometry and dual-energy X-ray absorptiometry in the measurement of thoracic vertebral bone mineral density: compressive force versus bone mineral.

    PubMed

    Myers, T J; Battocletti, J H; Mahesh, M; Gulati, M; Wilson, C R; Pintar, F; Reinartz, J

    1994-05-01

    31P nuclear magnetic resonance spectroscopy (NMRS) measurements were made on human T2 and T3 vertebral bodies. The bone mineral content (BMC) of isolated vertebral bodies minus the posterior elements and disks was measured using (1) NMRS on a 3.5 T, 85 mm bore GE Medical Systems NT-150 superconducting spectrometer, (2) a Lunar Corporation DPX-L dual-energy X-ray absorptiometry (DXA) scanner in an anterior-posterior (AP) orientation, (3) a Norland Corporation XR26 DXA scanner, also in an AP direction, and (4) a Norland Corporation model 2600 dual-photon absorptiometry (DPA) densitometer in both the AP and superior-inferior (SI) directions. Vertebral body volumes were measured using a water displacement technique to determine volume bone mineral densities (VBMD). They were then compressed to failure using an electrohydraulic testing device, followed by ashing in a muffle furnace at 700 degrees C for 18 h. Correlations of BMC between NMRS and DPA, DXA and ashing were excellent (0.96 < or = r < or = 0.99); in a one-way analysis of variance (ANOVA) test, means were not statistically different at a p level of 0.757. The correlations of VBMD between NMRS and the other methods were not as good (0.83 < or = r < or = 0.95); in a one-way ANOVA test, means were not statistically different at a p level of 0.089. BMC was a better predictor of ultimate compressive failure than VBMD for all six methods. For NMRS, the regression coefficient for BMC was r2 = 0.806, compared with r2 = 0.505 for VBMD. NMRS may prove an alternative to present methods of determining bone mineral. PMID:8069051

  13. Relationship between body composition and both cardiovascular risk factors and lung function in systemic sclerosis.

    PubMed

    Caramaschi, Paola; Biasi, Domenico; Caimmi, Cristian; Barausse, Giovanni; Gatti, Davide; Ferrari, Marcello; Pieropan, Sara; Sabbagh, Dania; Adami, Silvano

    2014-01-01

    The aims of this study were to evaluate body composition in systemic sclerosis (SSc) and to assess its association with the traditional risk factors for atherosclerosis and parameters of lung function. Eighty-six patients affected by SSc (13 men and 73 women, mean age 58.5 years, mean disease duration 10.7 years, 31 with diffuse form and 55 with limited pattern) underwent evaluation of body composition using a dual-energy X-ray (DXA) fan beam densitometer (GE Lunar iDXA) in order to assess total and regional body fat mass and fat-free mass. Clinical features, pulmonary function parameters, and the concomitant presence of the traditional cardiovascular risk factors were recorded. Android fat resulted to be higher in SSc patients with coexistence of hypercholesterolemia (P = 0.021), hypertension (P = 0.028), and overweight/obesity (P < 0.001) and positively correlated with body mass index (P < 0.001). Forced vital capacity (FVC) was inversely correlated with android fat (P = 0.034) and with the android fat/gynoid fat ratio (P = 0.013) and positively correlated with android lean (P = 0.041); the correlations were improved when FVC data were adjusted for sex, age, disease duration, and smoking habits (P = 0.010 for android fat, P = 0.010 for android fat/gynoid fat ratio, P = 0.011 for android lean). In this study, we showed that visceral abdominal fat, measured by DXA, is correlated with the main cardiovascular risk factors and lung volumes in SSc patients. Longitudinal studies are needed to evaluate if decrease of abdominal fat would improve lung function. PMID:24052413

  14. Does Visceral Fat Estimated by Dual-Energy X-ray Absorptiometry Independently Predict Cardiometabolic Risks in Adults?

    PubMed Central

    Sasai, Hiroyuki; Brychta, Robert J.; Wood, Rachel P.; Rothney, Megan P.; Zhao, Xiongce; Skarulis, Monica C.; Chen, Kong Y.

    2015-01-01

    Background: Abdominal visceral fat, typically measured by computer tomography (CT) or magnetic resonance imaging (MRI), has been shown to correlate with cardiometabolic risks. The purpose of this study was to examine whether a newly developed and validated visceral fat measurement from dual-energy X-ray absorptiometry (DXA) provides added predictive value to the cross-sectional differences of cardiometabolic parameters beyond the traditional anthropometric and DXA adiposity parameters. Method: A heterogeneous cohort of 194 adults (81 males and 113 females) with a BMI of 19 to 54 kg/m2 participated in this cross-sectional study. Body composition was measured with a DXA densitometer. Visceral fat was then computed with a proprietary algorithm. Insulin sensitivity index (SI, measured by intravenous glucose tolerance test), blood pressures, and lipid profiles, and peak oxygen uptake were also measured as cardiometabolic risk parameters. Results: DXA-estimated visceral fat mass was associated with HDL cholesterol (regression coefficient [β] = −5.15, P < .01, adjusted R2 = .21), triglyceride (β = 26.01, P < .01, adjusted R2 = .14), and peak oxygen uptake (β = −3.15, P < .01, adjusted R2 = .57) after adjusting for age, gender, and ethnicity. A subanalysis stratifying gender-specific BMI tertiles showed visceral fat, together with ethnicity, was independently associated with SI in overweight men and moderately obese women (second tertile). Conclusions: Without requiring additional CT or MRI-based measurements, visceral fat detected by DXA might offer certain advantages over the traditional DXA adiposity parameters as means of assessing cardiometabolic risks. PMID:25802470

  15. Chronic lead poisoning magnifies bone detrimental effects in an ovariectomized rat model of postmenopausal osteoporosis.

    PubMed

    Lee, Ching Ming; Terrizzi, Antonela Romina; Bozzini, Clarisa; Piñeiro, Adriana Emilce; Conti, María Inés; Martínez, María Pilar

    2016-01-01

    Lead (Pb) is a persistent environmental contaminant that is mainly stored in bones being an important source of endogenous lead exposure during periods of increased bone resorption as occurs in menopause. As no evidence exists of which bone biomechanical properties are impaired in those elderly women who had been exposed to Pb during their lifetime, the aim of the present study is to discern whether chronic lead poisoning magnifies the deterioration of bone biology that occurs in later stages of life. We investigated the effect of Pb in the femora of ovariectomized (OVX) female Wistar rats who had been intoxicated with 1000 ppm of Pb acetate in drinking water for 8 months. Structural properties were determined using a three-point bending mechanical test, and geometrical and material properties were evaluated after obtaining the load/deformation curve. Areal Bone Mineral Density (BMD) was estimated using a bone densitometer. Femoral histomorphometry was carried out on slices dyed with H&E (Hematoxylin and Eosin). Pb and OVX decreased all structural properties with a higher effect when both treatments were applied together. Medullar and cortical area of femurs under OVX increased, allowing the bone to accommodate its architecture, which was not observed under Pb intoxication. Pb and OVX significantly decreased BMD, showing lead treated ovariectomized rats (PbOVX) animals the lowest BMD levels. Trabecular bone volume per total volume (BV/TV%) was decreased in OVX and PbOVX animals in 54% compared to the control animals (p<0.001). Pb femurs also showed 28% less trabeculae than the control (p<0.05). We demonstrated that Pb intoxication magnifies the impairment in bone biomechanics of OVX rats with a consequent enhancement of the risk of fracture. These results enable the discussion of the detrimental effects of lead intoxication in bone biology in elderly women. PMID:26422677

  16. Serum C-reactive protein in dairy herds

    PubMed Central

    Lee, Wen-Chuan; Hsiao, Huo-Cheng; Wu, Ying-Ling; Lin, Jyh-Hung; Lee, Yen-Pai; Fung, Hang-Poung; Chen, Hsin-Hsin; Chen, Yu-Hsin; Chu, Rea-Min

    2003-01-01

    The purpose of this study was to determine the relationship between the serum level of C-reactive protein (CRP) and lactation and health status. Blood samples were collected every 2 wk for 12 mo from 29 randomly selected dairy cattle on 3 farms. At the time the blood samples were collected, the stage of pregnancy, lactation status, breeding records, general health condition, reproductive status, and body condition score were recorded for each cow. Serum CRP was detected with sodium dodecyl sulfate polyacrylamide gel electrophoresis and western immunoblotting. C-reactive protein levels were measured with a densitometer and expressed as an optimal dose value. C-reactive protein levels were correlated with the body condition score, lactation status, and animal health (P < 0.05), but not with ambient temperature, animal age, or parity. C-reactive protein levels increased with milk production, peaking during high lactation (2 to 4 mo of pregnancy), and decreased when lactation ceased. In addition, the CRP level was highest during naturally occurring infections, such as mastitis and other tissue inflammation. Thus, the CRP level can confirm the presence of inflammation. The stress effect of taking blood samples as measured by the CRP level, was also examined. The CRP level became rapidly elevated 12 h after the blood samples were taken but returned to normal 36 h later. In conclusion, the stresses resulting from overall poor health, heavy lactation, and blood sampling caused the elevation of serum CRP. C-reactive protein is a marker or tool for evaluating the health status of a herd. C-reactive protein should also be considered as a useful criteria to assess the stress levels and may be useful in early surveillance of disease conditions in a dairy herd. PMID:12760474

  17. HYDRODYNAMIC MODELS FOR SLURRY BUBBLE COLUMN REACTORS. FINAL TECHNICAL REPORT ALSO INCLUDES THE QUARTERLY TECHNICAL REPORT FOR THE PERIOD 01/01/1997 - 03/31/1997.

    SciTech Connect

    DIMITRI GIDASPOW

    1997-08-15

    The objective of this study is to develop a predictive experimentally verified computational fluid dynamic (CFD) three phase model. It predicts the gas, liquid and solid hold-ups (volume fractions) and flow patterns in the industrially important bubble-coalesced (churn-turbulent) regime. The input into the model can be either particulate viscosities as measured with a Brookfield viscometer or effective restitution coefficient for particles. A combination of x-ray and {gamma}-ray densitometers was used to measure solid and liquid volume fractions. There is a fair agreement between the theory and the experiment. A CCD camera was used to measure instantaneous particle velocities. There is a good agreement between the computed time average velocities and the measurements. There is an excellent agreement between the viscosity of 800 {micro}m glass beads obtained from measurement of granular temperature (random kinetic energy of particles) and the measurement using a Brookfield viscometer. A relation between particle Reynolds stresses and granular temperature was found for developed flow. Such measurement and computations gave a restitution coefficient for a methanol catalyst to be about 0.9. A transient, two-dimensional hydrodynamic model for production of methanol from syn-gas in an Air Products/DOE LaPorte slurry bubble column reactor was developed. The model predicts downflow of catalyst at the walls and oscillatory particle and gas flow at the center, with a frequency of about 0.7 Hertz. The computed temperature variation in the rector with heat exchangers was only about 5 K, indicating good thermal management. The computed slurry height, the gas holdup and the rate of methanol production agree with LaPorte's reported data. Unlike the previous models in the literature, this model computes the gas and the particle holdups and the particle rheology. The only adjustable parameter in the model is the effective particle restitution coefficient.

  18. COMPUTATIONAL AND EXPERIMENTAL MODELING OF SLURRY BUBBLE COLUMN REACTORS

    SciTech Connect

    Paul Lam; Dimitri Gidaspow

    2000-09-01

    The objective if this study was to develop a predictive experimentally verified computational fluid dynamics (CFD) model for gas-liquid-solid flow. A three dimensional transient computer code for the coupled Navier-Stokes equations for each phase was developed. The principal input into the model is the viscosity of the particulate phase which was determined from a measurement of the random kinetic energy of the 800 micron glass beads and a Brookfield viscometer. The computed time averaged particle velocities and concentrations agree with PIV measurements of velocities and concentrations, obtained using a combination of gamma-ray and X-ray densitometers, in a slurry bubble column, operated in the bubbly-coalesced fluidization regime with continuous flow of water. Both the experiment and the simulation show a down-flow of particles in the center of the column and up-flow near the walls and nearly uniform particle concentration. Normal and shear Reynolds stresses were constructed from the computed instantaneous particle velocities. The PIV measurement and the simulation produced instantaneous particle velocities. The PIV measurement and the simulation produced similar nearly flat horizontal profiles of turbulent kinetic energy of particles. This phase of the work was presented at the Chemical Reaction Engineering VIII: Computational Fluid Dynamics, August 6-11, 2000 in Quebec City, Canada. To understand turbulence in risers, measurements were done in the IIT riser with 530 micron glass beads using a PIV technique. The results together with simulations will be presented at the annual meeting of AIChE in November 2000.

  19. The Maria Mitchell Observatory and its Digitized Plate Collection

    NASA Astrophysics Data System (ADS)

    Strelnitski, V.

    2009-08-01

    The Maria Mitchell Observatory (MMO), located on Nantucket Island, possesses a collection of over 8,000 wide-field (13° x 16°) photographic plates obtained with the MMO 7.5-inch (19-cm) Cooke/Clark camera, from 1913 to 1995. The collection is relatively rich for three areas of the sky in Scutum, Cygnus and Sagittarius. The catalog of the plates is available online. In 2000-2002, all the plates were digitized with an AgfaScan T5000 commercial scanner, using both low (840 dpi) and high (2,500 dpi) resolution and the 8 bit gray scale resolution. The image files are stored on CDs and on hard drive RAID-protected storage devices, and copies (on CDs or DVDs) are available on order. Comparison of the images scanned with the AgfaScan T5000 and those scanned with the STScI high-precision GAMMA laser densitometer reveals a characteristic additional noise of up to ≈0.05 mag on the AgfaScan T5000 scans. It is considerably lower than the typical uncertainty of ±0.1-0.2 mag for stellar photometry on the original MMO plates. Several successful projects using the scanned copies of the plates confirm the adequacy of the copies for stellar photometry. Considering that the high-resolution scanning on AgfaScan T5000 was eight times faster than that with the GAMMA, we conclude that scanning the plates of this quality with a commercial scanner of the AgfaScan T5000 class is a reasonable compromise between the quality and the time and cost of scanning.

  20. Characterization of a multileaf collimator system

    SciTech Connect

    Galvin, J.M. ); Smith, A.R. ); Lally, B. )

    1993-01-15

    Commissioning measurements for a multileaf collimator installed on a dual energy accelerator with 6 and 15 MV photons are described. Detailed dosimetric characterization of the multileaf collimator is a requirement for modeling the collimator with treatment planning software. Measurements include a determination of the penumbra width, leaf transmission, between-leaf leakage, and localization of the leaf ends and sides. Standard radiographic film was used for the penumbra measurements, and separate experiments using radiochromic film and thermoluminescent dosimeters were performed to verify that distortions of the dose distribution at an edge due to changing energy sensitivity of silver bromide film are negligible. Films were analyzed with a scanning laser densitometer with a 210 micron spot. Little change in the penumbra edge distribution was noted for different positions of a leaf in the field. Experiments localizing the physical end of the leaves showed less than 1 mm deviation from the 50% decrement line. This small difference is attributed to the shaped end on the leaves. One side of a single leaf corresponded to the 50% decrement line, but the opposite face was aligned with a lower value. This difference is due to the tongue and groove used to decrease between-leaf leakage. For both energies, approximately 2% of photons incident on the multileaf collimator are transmitted and an additional 0.5% leakage occurs between the leaves. Alignment of the leaves to form a straight edge results in a penumbra profile which compares favorably with the standard technique of using alloy blocks. When the edge is stepped, the isodose lines follow the leaf pattern and the boundary is poorly defined compared to divergent blocks. 19 refs., 13 figs.

  1. Effect of High Impact or Non-impact Loading Activity on Bone Bending Stiffness and Mineral Density

    NASA Technical Reports Server (NTRS)

    Liang, Michael T. C.; Arnnud, Sara B.; Steele, Charles R.; Moreno, Alexjandro

    2003-01-01

    Material properties of conical bone, including mineral density (BMD) and its geometry is closely related to its load-carrying capacity. These two primary components determine the strength of conical bone. High impact loading involving acceleration and deceleration movements used in gymnastics induce higher BMD of the affected bone compared to the non-impact acceleration and deceleration movements used in swimming. Study of these two groups of athletes on bone bending stiffness has not been reported. The purpose of this study was to compare differences in bone bending stiffness and BMD between competitive female synchronized swimmers and female gymnasts. Thirteen world class female synchronized swimmers (SYN) and 8 female gymnasts (GYM), mean age 21 +/- 2.9 yr. were recruited for this study. We used a mechanical response tissue analyzer (Gaitscan, NJ) to calculate EI, where E is Young's modulus of elasticity and I is the cross-sectional moment of inertia. EI was obtained from tissue response to a vibration probe placed directly on the skin of the mid-region of tibia and ulna. BMD of the heel and wrist were measured with a probe densitometer (PIXI, Lunor, WI). The SYN were taller than (p < 0.05) the GYM but weighed the same as the GYM. EI obtained from tibia and ulna of the SYN (291 +/- 159 and 41 +/- 19.4, respectively) were not significantly different from thc GYM (285 +/- 140 and 44 +/- 18.3, respectively). BMD of the heel and wrist in GYM were higher than in SYN (p < 0.001). High impact weight-bearing activities promote similar bone strength but greater BMD response than non-impact activities performed in a buoyant environment.

  2. The criteria for measuring average density by x-ray attenuation: The role of spatial resolution

    SciTech Connect

    Friedman, W.

    1999-07-29

    It is well known that the attenuation of X-rays as they pass through a material can be used to quantify the amount of matter in their path. This is the basis for the gamma ray densitometer which can measure the amount of material on a moving conveyor belt. It is also the rationale for using X-rays for medical imaging as the attenuation can discriminate between tissue of different density and composition, yielding images of great diagnostic utility. Spatial resolution is obviously important with regard to detecting small features. However, it is less obvious that it plays an important role in obtaining quantitative information from the X-ray transmission data since the spatial resolution of the instrument can affect the accuracy of those measurements. This problem is particularly severe in the case of computed tomography where the accuracy of the reconstruction is dependent on the accuracy of the initial projection data. It should be noted that spatial resolution is not a concern for the case where the material is uniform. Here uniform is defined by small variations related to either the scale size of the resolution element in the detector, or to the size of a collimated X-ray beam. However, if the material has non-homogeneous composition or changes in density on the scale size of the systems spatial resolution, then there can be effects that will compromise the transmission data before it is acquired and these errors can not be corrected by any subsequent data processing. A method is presented for computing the density measurement error which parameterizes the effect in terms of the actual modulation on the face of the detector and the attenuation in the material. For cases like stacks of lead plates the errors can exceed 80%.

  3. Bone mineral density in survivors of childhood acute lymphoblastic leukemia.

    PubMed

    Athanassiadou, Fani; Tragiannidis, Athanassios; Rousso, Israel; Katsos, Georgios; Sidi, Vassiliki; Papageorgiou, Theodotis; Papastergiou, Christos; Tsituridis, Ioannis; Koliouskas, Dimitrios

    2006-01-01

    The aim of our study was to evaluate bone metabolism with measurement of bone mineral density (BMD) after management (chemo-, radiotherapy) for childhood acute lymphoblastic leukemia (ALL). Bone mineral density (g/cm2) of lumbar spine was measured by dual energy X-ray absorptiometry (Norland bone densitometer) in 18 children with ALL and a median of 34 months' post-diagnosis with no history of relapse, secondary malignancy, or transplantation. In addition, patients' BMDs were correlated with particular attention to age, sex and time (years) from completion of chemotherapy. The results were compared with healthy age- and sex-matched controls of the same population and expressed as standard deviation scores (SDS). Mean age of children was 9.8 +/- 3.7 years. Of 18 children (10 boys and 8 girls), 13 were grouped as standard and 5 as high-risk, respectively. Based on z-score values, 9 were classified as normal (z-score <1 SD), 7 as osteopenic (z-score 1-2.5 SD) and 2 as osteoporotic (z-score >2.5 SD). Children with ALL had reduced lumbar BMDs (z score -0.99) in comparison to healthy controls (z score -0.14) (p=0.011), which is indicative of relative osteopenia. Moreover, the reduced BMD was associated with patient age (z score -0.14 and -1.52 for ages <10 and >10 years, respectively, p=0.016). Reduced BMD was not correlated with time from completion of chemotherapy (p=0.33), risk group (p=0.9) and sex (p=0.3). We conclude that children's BMDs are reduced after completion of chemotherapy for ALL. The causes are multifactorial and mainly related to antineoplastic treatments, such as corticosteroids and methotrexate, physical inactivity and cranial irradiation. We suggest that further studies are needed to evaluate the long-term effect on BMD in these children and to prevent pathological fractures later in life. PMID:16848106

  4. DXA: Technical aspects and application.

    PubMed

    Bazzocchi, Alberto; Ponti, Federico; Albisinni, Ugo; Battista, Giuseppe; Guglielmi, Giuseppe

    2016-08-01

    The key role of dual-energy X-ray absorptiometry (DXA) in the management of metabolic bone diseases is well known. The role of DXA in the study of body composition and in the clinical evaluation of disorders which directly or indirectly involve the whole metabolism as they may induce changes in body mass and fat percentage is less known or less understood. DXA has a range of clinical applications in this field, from assessing associations between adipose or lean mass and the risk of disease to understanding and measuring the effects of pathophysiological processes or therapeutic interventions, in both adult and paediatric human populations as well as in pre-clinical settings. DXA analyses body composition at the molecular level that is basically translated into a clinical model made up of fat mass, non-bone lean mass, and bone mineral content. DXA allows total and regional assessment of the three above-mentioned compartments, usually by a whole-body scan. Since body composition is a hot topic today, manufacturers have steered the development of DXA technology and methodology towards this. New DXA machines have been designed to accommodate heavier and larger patients and to scan wider areas. New strategies, such as half-body assessment, permit accurate body scan and analysis of individuals exceeding scan field limits. Although DXA is a projective imaging technique, new solutions have recently allowed the differential estimate of subcutaneous and intra-abdominal visceral fat. The transition to narrow fan-beam densitometers has led to faster scan times and better resolution; however, inter- or intra-device variation exists depending on several factors. The purposes of this review are: (1) to appreciate the role of DXA in the study of body composition; (2) to understand potential limitations and pitfalls of DXA in the analysis of body composition; (3) to learn about technical elements and methods, and to become familiar with biomarkers in DXA. PMID:27157852

  5. Reducing the need for central dual-energy X-ray absorptiometry in postmenopausal women: efficacy of a clinical algorithm including peripheral densitometry.

    PubMed

    Jiménez-Núñez, Francisco Gabriel; Manrique-Arija, Sara; Ureña-Garnica, Inmaculada; Romero-Barco, Carmen María; Panero-Lamothe, Blanca; Descalzo, Miguel Angel; Carmona, Loreto; Rodríguez-Pérez, Manuel; Fernández-Nebro, Antonio

    2013-07-01

    We evaluated the efficacy of a triage approach based on a combination of osteoporosis risk-assessment tools plus peripheral densitometry to identify low bone density accurately enough to be useful for clinical decision making in postmenopausal women. We conducted a cross-sectional diagnostic study in postmenopausal Caucasian women from primary and tertiary care. All women underwent dual-energy X-ray absorptiometric (DXA) measurement at the hip and lumbar spine and were categorized as osteoporotic or not. Additionally, patients had a nondominant heel densitometry performed with a PIXI densitometer. Four osteoporosis risk scores were tested: SCORE, ORAI, OST, and OSIRIS. All measurements were cross-blinded. We estimated the area under the curve (AUC) to predict the DXA results of 16 combinations of PIXI plus risk scores. A formula including the best combination was derived from a regression model and its predictability estimated. We included 505 women, in whom the prevalence of osteoporosis was 20 %, similar in both settings. The best algorithm was a combination of PIXI + OST + SCORE with an AUC of 0.826 (95 % CI 0.782-0.869). The proposed formula is Risk = (-12) × [PIXI + (-5)] × [OST + (-2)] × SCORE and showed little bias in the estimation (0.0016). If the formula had been implemented and the intermediate risk cutoff set at -5 to 20, the system would have saved 4,606.34 in the study year. The formula proposed, derived from previously validated risk scores plus a peripheral bone density measurement, can be used reliably in primary care to avoid unnecessary central DXA measurements in postmenopausal women. PMID:23608922

  6. A prototype quantitative film scanner for radiochromic film dosimetry

    SciTech Connect

    Ranade, Manisha K.; Li, Jonathan G.; Dubose, Ryan S.; Kozelka, Jakub; Simon, William E.; Dempsey, James F.

    2008-02-15

    . The RCF rotated by 90 deg. showed no measurable orientation effect. A scan of a 15x15 cm{sup 2} area with 1 mm resolution required 22 min to acquire. The LED densitometer provides an accurate film dosimetry system with 1 mm or better resolution. The scanner eliminates the orientation dependence of RCF dosimetry that was previously reported with commercial flatbed scanners.

  7. Effects of a herbal extract on the bone density, strength and markers of bone turnover of mature ovariectomized rats.

    PubMed

    Xu, Min; Dick, Ian M; Day, Robert; Randall, Drew; Prince, Richard L

    2003-01-01

    For many decades, the Chinese have been using herbal medications to treat bone diseases. To examine effects of an extract of ten medicinal herbs on estrogen deficiency bone loss, ten-month-old female rats were randomly divided into three groups: ovariectomized (OVX), OVX treated with herbs (OVX-M) 4 ml/day by gavage, and OVX treated with estrogen (OVX-E) 10 mg subcutaneously (s.c.) twice per week. The bone mineral density (BMD) of the left femur (fBMD), spine (sBMD) and global body (gBMD) were measured at baseline and at 4, 8 and 12 weeks using a Hologic QDR 2000 dual-energy X-ray densitometer. Tibial strength was tested using the Instron Model 5566 electro-mechanical testing machine. The urinary pyridinoline creatinine ratio (Pyd/Cr), deoxypyridinoline creatinine ratio (Dpd/Cr), plasma alkaline phosphatase (ALP), calcium (CA), phosphorus (P) and albumin (ALB) were also determined. Uterine weight was determined at 12 weeks. The results showed that percent changes of fBMD in the OVX (n = 9), OVX-E (n = 8) and OVX-M (n = 8) rats at the 12-week time point were -11.8 +/- 4.6(c), 1.8 +/- 3.1(a), -7.6 +/- 1.9(abc) (p < 0.05-0.001, a: vs. OVX, b: vs. OVX-E, c: vs. baseline); sBMD were -10.7 +/- 4.6(c), -0.3 +/- 5.5(a), -5.9 +/- 3.5(abc); and gBMD were -4.8 +/- 2.3(c), 0.1 +/- 2.4(a), -2.7 +/- 2.6(abc), respectively. Further, the tibia maximum breaking stress and flexural modulus of elasticity in OVX-M rats (295 +/- 33(a), 18,194 +/- 3,264(a)) were significantly higher (p < 0.005-0.001) than that in OVX rats (189 +/- 83, 10,309 +/- 4,930), and similar to OVX-E rats (298 +/- 35(a), 18,766 +/- 2,620(a)). Additionally, the herbal extract reduced the urinary Pyd/Cr, Dpd/Cr and plasma ALP increment followed OVX and was not associated with a rise in uterine weight. In conclusion, the herbal extract demonstrated a therapeutic effect to inhibit bone resorption and to reduce estrogen-dependent bone loss without uterine stimulation. It may have potential as a new approach in

  8. Bioimpedence to Assess Breast Density as a Risk Factor for Breast Cancer in Adult Women and Adolescent Girls.

    PubMed

    Maskarinec, Gertraud; Morimoto, Yukiko; Laguana, Michelle B; Novotny, Rachel; Leon Guerrero, Rachael T

    2016-01-01

    Although high mammographic density is one of the strongest predictors of breast cancer risk, X-ray based mammography cannot be performed before the recommended screening age, especially not in adolescents and young women. Therefore, new techniques for breast density measurement are of interest. In this pilot study in Guam and Hawaii, we evaluated a radiation-free, bioimpedance device called Electrical Breast DensitometerTM (EBD; senoSENSE Medical Systems, Inc., Ontario, Canada) for measuring breast density in 95 women aged 31-82 years and 41 girls aged 8-18 years. Percent density (PD) was estimated in the women's most recent mammogram using a computer-assisted method. Correlation coefficients and linear regression were applied for statistical analysis. In adult women, mean EBD and PD values of the left and right breasts were 230±52 and 226±50 Ω and 23.7±15.1 and 24.2±15.2%, respectively. The EBD measurements were inversely correlated with PD (rSpearman=-0.52, p<0.0001); the correlation was stronger in Caucasians (rSpearman=-0.70, p<0.0001) than Asians (rSpearman=-0.54, p<0.01) and Native Hawaiian/Chamorro/Pacific Islanders (rSpearman=-0.34, p=0.06). Using 4 categories of PD (<10, 10-25, 26-50, 51-75%), the respective mean EBD values were 256±32, 249±41, 202±46, and 178±43 Ω (p<0.0001). In girls, the mean EBD values in the left and right breast were 148±40 and 155±54 Ω; EBD values decreased from Tanner stages 1 to 4 (204±14, 154±79, 136±43, and 119±16 Ω for stages 1-4, respectively) but were higher at Tanner stage 5 (165±30 Ω). With further development, this bioimpedance method may allow for investigations of breast development among adolescent, as well as assessment of breast cancer risk early in life and in populations without access to mammography. PMID:26838256

  9. Development and Assessment of Compton Scattered X-Ray Technique for Bone Density Measurement In-Vivo

    NASA Astrophysics Data System (ADS)

    Kapoor, Kulvir Kumar

    A Compton Scatter X-ray Bone Densitometer for Bone Density determination in-vivo is described. The system uses a single 90 kVp quasi-continuous X-ray source and three scintillation crystal detectors--two CsI(Na) scintillators for low flux scattered beam and one plastic scintillator for high flux transmission beam. Each density determination involves four intensity measurements using digital electronics --two of transmitted beams and two of compton scattered radiation. Theoretical studies are made on the contribution from multiple scattering phenomenon which limits the precise determination of density. Preliminary studies have been made on beam hardening effects which arise due to the polychromatic nature of X-ray photon beam. A number of spectra for transmitted and scattered X-ray beams have been taken under various configurations to make some qualitative assessment of the complexity of the problem involved. The main emphasis has been on the compromise between the radiation dose to the limited area of the human subject under investigation and the statistical precision of density measurement. In -vitro measurements on non-biological samples have been made to assess the accuracy and precision of the system before performing in-vivo studies on subjects. A series of normal volunteer human subjects selected at random from among the Carleton University community has been studied to collect density data for normals. The site chosen for density measurement was in the tibia of right leg of the subject. Using linear regression, measurements were normalized to 40 yrs age & 70 kg wt for male subjects and 40 yrs age & 60 kg wt for female subjects. It is found that the bone density values thus obtained had a mean of 1.35 g/cm('3) with FWHM of 0.20 g/cm('3) for males and 0.35 g/cm('3) for females. The frequency distribution of density values showed they were skewed towards higher density from mean value and peaked at 1.48 g/cm('3) both for male and female subjects. In

  10. Altered body composition in type 2 diabetes mellitus

    PubMed Central

    Heshka, Stanley; Ruggiero, Andrea; Bray, George A.; Foreyt, John; Kahn, Stephen E.; Lewis, Cora E.; Saad, Mohammed; Schwartz, Ann V.

    2010-01-01

    Objective To identify differences in amount and distribution of fat and lean soft tissue in subjects with and without type 2 diabetes and to determine whether any differences are affected by race/ethnicity or sex. Design Overweight and obese (body mass index, BMI≥25 kg/m2) Black, White and Hispanic men (490) and women (825) with type 2 diabetes ([mean±SD] age 58.5±6.6; BMI 35.3±5.3) who had a baseline dual energy x-ray absorptiometry whole body scan at the time of enrollment in the Look Ahead clinical trial, and 242 healthy controls, 91 males and 151 females (age 55.3±8.6 y, BMI 30.7±4.2 kg/m2) who were participating in unrelated research and were scanned on the same densitometers. Results Adjusted for covariates, total fat mass was smaller in persons with type 2 diabetes than in controls (−1.4±0.3[SE]; 34.5 vs 35.8 kg, p<0.001) while trunk fat was larger (1.3±0.2[SE]; 19.9 vs 18.6 kg, p<0.001) and leg fat was smaller (−1.5±0.2[SE]; 10.7 vs 12.3 kg, p<0.001). The arms of subjects with type 2 diabetes did not have significantly less fat compared to controls. Adjusted trunk lean mass was larger in type 2 diabetes by 0.6 kg (28.4 vs 27.8 kg, p<0.001) while leg lean was smaller by 0.5 kg (18.1 vs 18.6 kg, p<0.001). Conclusions Type 2 diabetes is associated with less total fat, leg fat and leg lean mass and more truncal fat and lean mass than controls. The physiological processes producing these deviations in tissue distribution and their metabolic significance warrant further investigation. (ClinicalTrials.gov number, NCT00017953) PMID:18227843

  11. High pressure annular two-phase flow in a narrow duct. Part 1: Local measurements in the droplet field, and Part 2: Three-field modeling

    SciTech Connect

    Trabold, T.A.; Kumar, R.

    1999-07-01

    In Part 1, detailed measurements were made in a high pressure, adiabatic (boiled at the inlet) annular flow in a narrow, high aspect ratio duct using a gamma densitometer, hot-film anemometer and high-speed video photography. Measurements of void fraction, droplet frequency, velocity, drop size, and interfacial area concentration have been made to support the three field computational capability. An important aspect of this testing is the use of a modeling fluid (R-134a) in a vertical duct which permits visual access in annular flow. This modeling fluid accurately simulates the low liquid-to-vapor density ratio of steam-water flows at high pressures. These measurements have been taken in a narrow duct of hydraulic diameter 4.85 mm, and a cross-section aspect ratio of 22.5. However, the flow displays profiles of various shapes not only in the narrow dimension, but also in the width dimension. In particular, the shape of the droplet profiles depends on the entrained droplet flux from the edges in the vapor core. The average diameter from these profiles compare well with the models developed in the literature. Interfacial area concentration for these low density ratio flows is higher than the highest concentration reported for air-water flows. Video records show that along with the bow-shaped waves, three-dimensional {lambda}-shaped waves appear in annular flows for high flow rates. Part 2 outlines the development of a three-field modeling approach in annular flow and the predictive capability of an analysis code. Models have been developed here or adapted from the literature for the thin film near the wall as well as the droplets in the vapor core, and have been locally applied in a fully developed, two-phase adiabatic boiling annular flow in a duct heated at the inlet at high pressure. Numerical results have been obtained using these models that are required for the closure of the continuity and momentum equations. The two-dimensional predictions are compared with

  12. Bone density variation and its effects on risk of vertebral deformity in men and women studied in thirteen European centers: the EVOS Study.

    PubMed

    Lunt, M; Felsenberg, D; Reeve, J; Benevolenskaya, L; Cannata, J; Dequeker, J; Dodenhof, C; Falch, J A; Masaryk, P; Pols, H A; Poor, G; Reid, D M; Scheidt-Nave, C; Weber, K; Varlow, J; Kanis, J A; O'Neill, T W; Silman, A J

    1997-11-01

    , after adjusting for BMD, age, and BMI together with an a posteriori statistical adjustment for imperfect cross-calibration of densitometers. It is concluded that BMD is an important determinant of deformity risk in both genders. Together with age, BMD explains much of the differences in risk both between the sexes and between individual geographical centers in Europe. PMID:9383693

  13. Advanced radiochromic film methodologies for quantitative dosimetry of small and nonstandard fields

    NASA Astrophysics Data System (ADS)

    Rosen, Benjamin S.

    Radiotherapy treatments with small and nonstandard fields are increasing in use as collimation and targeting become more advanced, which spare normal tissues while increasing tumor dose. However, dosimetry of small and nonstandard fields is more difficult than that of conventional fields due to loss of lateral charged-particle equilibrium, tight measurement setup requirements, source occlusion, and the volume-averaging effect of conventional dosimeters. This work aims to create new small and nonstandard field dosimetry protocols using radiochromic film (RCF) in conjunction with novel readout and analysis methodologies. It also is the intent of this work to develop an improved understanding of RCF structure and mechanics for its quantitative use in general applications. Conventional digitization techniques employ white-light, flatbed document scanners or scanning-laser densitometers which are not optimized for RCF dosimetry. A point-by-point precision laser densitometry system (LDS) was developed for this work to overcome the film-scanning artifacts associated with the use of conventional digitizers, such as positional scan dependence, off-axis light scatter, glass bed interference, and low signal-to-noise ratios. The LDS was shown to be optically traceable to national standards and to provide highly reproducible density measurements. Use of the LDS resulted in increased agreement between RCF dose measurements and the single-hit detector model of film response, facilitating traceable RCF calibrations based on calibrated physical quantities. GafchromicRTM EBT3 energy response to a variety of reference x-ray and gamma-ray beam qualities was also investigated. Conventional Monte Carlo methods are not capable of predicting film intrinsic energy response to arbitrary particle spectra. Therefore, a microdosimetric model was developed to simulate the underlying physics of the radiochromic mechanism and was shown to correctly predict the intrinsic response relative to a

  14. Can the material properties of regenerate bone be predicted with non-invasive methods of assessment? Exploring the correlation between dual X-ray absorptiometry and compression testing to failure in an animal model of distraction osteogenesis.

    PubMed

    Monsell, Fergal; Hughes, Andrew William; Turner, James; Bellemore, Michael C; Bilston, Lynne

    2014-04-01

    Evaluation of the material properties of regenerate bone is of fundamental importance to a successful outcome following distraction osteogenesis using an external fixator. Plain radiographs are in widespread use for assessment of alignment and the distraction gap but are unable to detect bone formation in the early stages of distraction osteogenesis and do not quantify accurately the structural properties of the regenerate. Dual X-ray absorptiometry (DXA) is a widely available non-invasive imaging modality that, unlike X-ray, can be used to measure bone mineral content (BMC) and density quantitatively. In order to be useful as a clinical investigation; however, the structural two-dimensional geometry and density distributions assessed by DXA should reflect material properties such as modulus and also predict the structural mechanical properties of the regenerate bone formed. We explored the hypothesis that there is a relationship between DXA assessment of regenerate bone and structural mechanical properties in an animal model of distraction osteogenesis. Distraction osteogenesis was carried out on the tibial diaphysis of 41 male, 12 week old, New Zealand white rabbits as part of a larger study. Distraction started after a latent period of 24 h at a rate of 0.375 mm every 12 h and continued for 10-days, achieving average lengthening of 7.1 mm. Following an 18-day period of consolidation, the regenerate bone was subject to bone density measurements using a total body dual-energy X-ray densitometer. This produced measurement of BMC, bone mineral density (BMD) and volumetric bone mineral density (vBMD). The tibiae were then disarticulated and cleaned of soft tissue before loading in compression to failure using an Instron mechanical testing machine (Instron Corporation, Massachusetts USA). Using Spearman rank correlation and linear regression, there was a significant correlation between vBMD and the Modulus of Elasticity, Yield Stress and Failure Stress of the

  15. Correlations between the MR Diffusion-weighted Image (DWI) and the bone mineral density (BMD) as a function of the soft tissue thickness-focus on phantom and patient

    NASA Astrophysics Data System (ADS)

    Kim, Myung-Sam; Cho, Jae-Hwan; Lee, Hae-Kag; Lee, Sang-Jeong; Park, Cheol-Soo; Dong, Kyung-Rae; Park, Yong-Soon; Chung, Woon-Kwan; Lee, Jong-Woong; Kim, Ho-Sung; Kim, Eun-Hye; Kweon, Dae Cheol; Yeo, Hwa-Yeon

    2013-02-01

    In this study we used lumbar phantoms to determine if the BMD (bone mineral density) changes when only the thickness of soft tissue is increased. Second, we targeted osteoporosis patients to analyze the dependences of the changes in the SNR (signal-to-noise ratio) and the ADC (apparent diffusion coefficient) on changes in T-score. We used a bone mineral densitometer, phantoms such as an aluminum spine phantom (ASP), a Hologic spine phantom (HSP), and a European spine phantom (ESP), five sheets of acrylic panel, and a water bath to study the effects of changes in the thickness of soft tissue. First, we measured the ASP, the HSP and the ESP. For the measurement of the ASP, we filled it with water to increase the height by 0.5 cm starting from the baseline height. We then did three measurements for each height. For the measurements of the HSP and the ESP, we placed an acrylic panel on the phantom and then did three measurements at each height. We used the ASP to calculate the degree of precision of the standard mode and the thick mode at the maximum height of the water bath. To assess the degree of precision in the measurements of the three types of phantoms, we calculated precision errors and analyzed the correlation between the change in the thickness of soft tissue and the variables of the BMD. Using DWIs (diffusion weighted images), we targeted 30 healthy persons without osteoporosis and 30 patients with a finding of osteoporosis and measured the T-scores for the L1 — L4 (lumbar spine) segments of by the spine using the dual-energy X-ray absorptiometry (DXA) before classifying the measurement at each part of the spine as osteopenia or osteoporosis. We measured the signal intensity on all four parts of L1-L4 in the DWIs obtained using a 1.5T MR scanner and measured the ADC in the ADC map image. We compared changes in the SNR and the ADC for each group. The study results confirmed that an increase in the thickness of the soft tissue had a significant correlation

  16. The utility of using customized heterochromatic flicker photometry (cHFP) to measure macular pigment in patients with age-related macular degeneration.

    PubMed

    Stringham, J M; Hammond, B R; Nolan, J M; Wooten, B R; Mammen, A; Smollon, W; Snodderly, D M

    2008-11-01

    The purpose of this study was to assess the utility and validity of using customized heterochromatic flicker photometry (cHFP) to measure macular pigment optical density (MPOD) in patients with intermediate stages of age-related macular degeneration (AMD). The measurement procedure was optimized to accommodate individual differences in temporal vision related to age, disease, or other factors. The validity criteria were based on the similarity of the spectral absorption curves to ex vivo curves of lutein and zeaxanthin and the similarity of spatial density profiles to those measured in subjects without retinal disease. Macular pigment optical density (MPOD) spatial profiles were measured with an LED-based macular densitometer; spectral absorption curves were measured with a 3-channel Maxwellian view system including a monochromator. All patients were characterized via clinical exams and all but 2 subjects from whom data were obtained had masked grading of color fundus photographs using the Wisconsin Age-Related Maculopathy Grading System. Most of the patients were in AREDS category 2 (27%) or 3 (57%). Patients with visual acuity as poor as 20/80 were included, and could perform the task as long as they could see the stimulus. Eighty-one percent of the patients screened were able to perform the cHFP task, and data were obtained from 30 AMD patients. Spatial profiles of MPOD were measured in 19 subjects who could see the stimulus at all tested loci. These profiles were highly similar to those that have been measured with HFP in subjects without retinal disease. The average shape of the spectral absorption curves for the AMD subjects corresponded well to an ex vivo template. These data support both the utility and validity of the cHFP method for measuring MPOD in subjects with intermediate stages of AMD. The ability to measure the retinal response to nutritional intervention is of practical importance for monitoring patients being supplemented with lutein and

  17. Mobile Munitions Assessment System Field Capabilities

    SciTech Connect

    A. M. Snyder; D. A. Verrill; K. D. Watts

    1999-05-27

    The US has developed, stored, tested, and conducted disposal operations on various forms of chemical munitions for several decades. The remnants of these activities have resulted in the presence of suspect CWM at more than 200 sites in the US, the District of Columbia, and the US Virgin Islands. An advanced Mobile Munitions Assessment System (Phase II MMAS) has been designed, fabricated, assembled, and tested by the Idaho National Engineering and Environmental Laboratory under contract to the US Army's Project Manager for Non-Stockpile Chemical Materiel for use in the assessment and characterization of ''non-stockpile'' chemical warfare materiel (CWM). The Phase II MMAS meets the immediate need to augment response equipment currently used by the US Army with a system that includes state-of-the-art assessment equipment and advanced sensors. The Phase II MMAS will be used for response to known storage and remediation sites. This system is designed to identify the munition type; evaluate the condition of the CWM; evaluate the environmental conditions in the vicinity of the CWM; determine if fuzes, bursters, or safety and arming devices are in place; identify the chemical fill; provide other data (e.g., meteorological data) necessary for assessing the risk associated with handling, transporting, and disposing of CWM; and record the data on a dedicated computer system. The Phase II MMAS is capable of over-the-road travel and air transport to any site for conducting rigorous assessments of suspect CWM. The Phase II MMAS utilizes a specially-designed commercial motor home to provide a means to transport an interactive network of non-intrusive characterization and assessment equipment. The assessment equipment includes radiography systems, a gamma densitometer system, a Portable Isotopic Neutron Spectroscopy (PINS) system, a Secondary Ion Mass Spectroscopy (SIMS) system, air monitoring equipment (i.e., M-90s and a field ion spectroscopy system), and a phase determination

  18. Bone Mass and Strength in School-Age Children Exhibit Sexual Dimorphism Related to Differences in Lean Mass: The Generation R Study.

    PubMed

    Medina-Gomez, Carolina; Heppe, Denise Hm; Yin, Jia-Lian; Trajanoska, Katerina; Uitterlinden, André G; Beck, Thomas J; Jaddoe, Vincent Wv; Rivadeneira, Fernando

    2016-05-01

    Bone strength, a key determinant of fracture risk, has been shown to display clear sexual dimorphism after puberty. We sought to determine whether sex differences in bone mass and hip bone geometry as an index of strength exist in school-age prepubertal children and the degree to which the differences are independent of body size and lean mass. We studied 3514 children whose whole-body and hip scans were measured using the same densitometer (GE-Lunar iDXA) at a mean age of 6.2 years. Hip dual-energy X-ray absorptiometry (DXA) scans underwent hip structural analyses (HSA) with derivation of bone strength indices. Sex differences in these parameters were assessed by regression models adjusted for age, height, ethnicity, weight, and lean mass fraction (LMF). Whole-body bone mineral density (BMD) and bone mineral content (BMC) levels were 1.3% and 4.3% higher in girls after adjustment by LMF. Independent of LMF, boys had 1.5% shorter femurs, 1.9% and 2.2% narrower shaft and femoral neck with 1.6% to 3.4% thicker cortices than girls. Consequent with this geometry configuration, girls observed 6.6% higher stresses in the medial femoral neck than boys. When considering LMF, the sexual differences on the derived bone strength indices were attenuated, suggesting that differences in muscle loads may reflect an innate disadvantage in bone strength in girls, as consequence of their lower muscular acquisition. In summary, we show that bone sexual dimorphism is already present at 6 years of age, with boys having stronger bones than girls, the relation of which is influenced by body composition and likely attributable to differential adaptation to mechanical loading. Our results support the view that early life interventions (ie, increased physical activity) targeted during the pre- and peripubertal stages may be of high importance, particularly in girls, because before puberty onset, muscle mass is strongly associated with bone density and geometry in children. © 2015 American

  19. Evaluation of Lunar small animal software for measuring bone mineral content in excised rat bones.

    PubMed

    Kiebzak, G M; Meyer, M H; Meyer, R A

    1999-01-01

    The purpose of this study was to evaluate software from Lunar Corporation (Madison, WI) designed for the measurement of bone mineral content ([BMC],g) in excised rat femurs using dual-energy X-ray absorptiometry (DXA). Femurs were harvested from intact 2- to 12-mo-old female Sprague-Dawley rats, stripped of soft tissues, wrapped in saline-soaked gauze, and frozen at -20 degrees F. Thawed bones were scanned in air on a 1.7-cm-thick Lucite plate that was laid on the manufacturer's supplied Delrin platform. Bones were in an anteroposterior position and scanned in a proximal-to-distal manner. Small animal software version 1.0d was used with a Lunar DPX-L densitometer. Regions of interest (ROIs) were the middle one-third of the diaphysis, a small central area of the distal metaphysis, and the total bone. Precision (n = 6 femurs) was calculated for each region of interest. After DXA scanning, one group of bones (n = 10 femurs) was dried and incinerated in a muffle furnace to obtain bone ash. The ash was then digested in acid and aliquots assayed for calcium using atomic absorption spectrophotometry. This group of bones was used to correlate BMC with ash weight and areal bone mineral density (BMD) with calcium concentration. A second group of bones (n = 14 femurs) was used to correlate BMC with maximal load to failure (N), a biomechanical variable that provides information about bone strength. Precision of repetitive measurements for the three ROIs was 1.2, 3.0, and 0.65%, respectively. Total femur BMC and total femur ash weights were significantly correlated (r = 0.974, p <0.0001). Total femur area BMD (g/cm2) was significantly correlated with calcium concentration (microM) of the bone hydrolysate (r = 0.686, p = 0.029). Total femur BMC and maximum load to midshaft fracture were also significantly correlated (r = 0.914, p<0.0001). The greatest problem with the software was with edge detection: operator intervention was necessary to place edges manually during scan

  20. Hologic QDR 2000 whole-body scans: a comparison of three combinations of scan modes and analysis software

    NASA Technical Reports Server (NTRS)

    Spector, E.; LeBlanc, A.; Shackelford, L.

    1995-01-01

    This study reports on the short-term in vivo precision and absolute measurements of three combinations of whole-body scan modes and analysis software using a Hologic QDR 2000 dual-energy X-ray densitometer. A group of 21 normal, healthy volunteers (11 male and 10 female) were scanned six times, receiving one pencil-beam and one array whole-body scan on three occasions approximately 1 week apart. The following combinations of scan modes and analysis software were used: pencil-beam scans analyzed with Hologic's standard whole-body software (PB scans); the same pencil-beam analyzed with Hologic's newer "enhanced" software (EPB scans); and array scans analyzed with the enhanced software (EA scans). Precision values (% coefficient of variation, %CV) were calculated for whole-body and regional bone mineral content (BMC), bone mineral density (BMD), fat mass, lean mass, %fat and total mass. In general, there was no significant difference among the three scan types with respect to short-term precision of BMD and only slight differences in the precision of BMC. Precision of BMC and BMD for all three scan types was excellent: < 1% CV for whole-body values, with most regional values in the 1%-2% range. Pencil-beam scans demonstrated significantly better soft tissue precision than did array scans. Precision errors for whole-body lean mass were: 0.9% (PB), 1.1% (EPB) and 1.9% (EA). Precision errors for whole-body fat mass were: 1.7% (PB), 2.4% (EPB) and 5.6% (EA). EPB precision errors were slightly higher than PB precision errors for lean, fat and %fat measurements of all regions except the head, although these differences were significant only for the fat and % fat of the arms and legs. In addition EPB precision values exhibited greater individual variability than PB precision values. Finally, absolute values of bone and soft tissue were compared among the three combinations of scan and analysis modes. BMC, BMD, fat mass, %fat and lean mass were significantly different between

  1. Performance of calcaneus quantitative ultrasound and dual-energy X-ray absorptiometry in the discrimination of prevalent asymptomatic osteoporotic fractures in postmenopausal women.

    PubMed

    El Maghraoui, A; Morjane, F; Mounach, A; Ghazi, M; Nouijai, A; Achemlal, L; Bezza, A; Ghozlani, I

    2009-03-01

    Due to its low cost, portability, and nonionizing radiation, quantitative ultrasound (QUS) of the heel is an alternative to the measurement with dual X-ray absorptiometry (DXA) in the evaluation of bone status. The objective of the study is to compare in asymptomatic postmenopausal women the ability of QUS and DXA to discriminate between those with and without prevalent vertebral fractures (VFs). The study cohort consists of a population of 295 postmenopausal women aged between 60 and 84 (mean age, weight and BMI of 66.3 years, 72.0 kg and 29.4 kg/m(2), respectively). Lateral VFA images and scans of the lumbar spine and proximal femur were obtained by two technologists using a GE Healthcare Lunar Prodigy densitometer. VFs were defined using a combination of Genant semiquantitative (SQ) approach and morphometry. All women had a calcaneous QUS examination. The mean age of the women in our sample was 66.3 (+/-5.3) years, ranging from 60 to 84 years. Eighty-seven (29.3%) women had VFs Genant grade 2 and 3. Patients with VFs had an age and a number of years of menopause higher to those without VFs, but showed lower height, weight, and BMI. All densitometric and ultrasonometric measurements were significantly reduced in women with VFs. The intercorrelations of BMD at different sites were high, and the correlations of BUA with BMD were lower. BUA correlated weakly with total hip BMD (r = 0.36), lumbar spine BMD (r = 0.32), and much less with femur BMD (r = 0.30); all correlations were significant (P < 0.01). Analysis of the AUC for the ROC curves showed lumbar spine T-score below -2.5 to provide consistently the highest AUC (0.64). Age-adjusted ORs after correction for confounding variables (years of menopause, weight, height, and BMI) for QUS and BMD measurements showed that only lumbar spine T-score below -2.5 could predict significantly the presence of VFs (OR, 1.94; 95%CI, 1.02-3.41). Lumbar spine BMD (and not QUS) was able to discriminate asymptomatic postmenopausal

  2. Energy dependence of response of new high sensitivity radiochromic films for megavoltage and kilovoltage radiation energies.

    PubMed

    Chiu-Tsao, Sou-Tung; Ho, Yunsil; Shankar, Ravi; Wang, Lin; Harrison, Louis B

    2005-11-01

    The purpose of this paper is to evaluate the energy dependence of the response of two new high sensitivity models of radiochromic films EBT and XR-QA. We determined the dose response curves of these films for four different radiation sources, namely, 6 MV photon beams (6 MVX), Ir-192, I-125, and Pd-103. The first type (EBT) is designed for intensity modulated radiation therapy (IMRT) dosimetry, and the second type (XR-QA) is designed for kilovoltage dosimetry. All films were scanned using red (665 nm) and green (520 nm) light sources in a charge-coupled device-based densitometer. The dose response curves [net optical density (NOD) versus dose] were plotted and compared for different radiation energies and light sources. Contrary to the early GAFCHROMIC film types (such as models XR, HS, MD55-2, and HD810), the net optical densities of both EBT and XR-QA were higher with a green (520 nm) than those with a red (665 nm) light source due to the different absorption spectrum of the new radiochromic emulsion. Both film types yield measurable optical densities for doses below 2 Gy. EBT film response is nearly independent of radiation energy, within the uncertainty of measurement. The NOD values of EBT film at 1 and 2 Gy are 0.13 and 0.25 for green, and 0.1 and 0.17 for red, respectively. In contrast, the XR-QA film sensitivity varies with radiation energy. The doses required to produce NOD of 0.5 are 6.9, 5.4, 0.7, and 0.9 Gy with green light and 19, 13, 1.7, and 1.5 Gy with red light, for 6 MVX, Ir-192, I -125, and Pd-103, respectively. EBT film was found to have minimal photon energy dependence of response for the energies tested and is suitable for dosimetry of radiation with a wide energy spectrum, including primary and scattered radiation. XR-QA film is promising for kilovoltage sources with a narrow energy spectra. The new high sensitivity radiochromic films are promising tools in radiation dosimetry. PMID:16370422

  3. Objective evaluation of slanted edge charts

    NASA Astrophysics Data System (ADS)

    Hornung, Harvey (.

    2015-01-01

    Camera objective characterization methodologies are widely used in the digital camera industry. Most objective characterization systems rely on a chart with specific patterns, a software algorithm measures a degradation or difference between the captured image and the chart itself. The Spatial Frequency Response (SFR) method, which is part of the ISO 122331 standard, is now very commonly used in the imaging industry, it is a very convenient way to measure a camera Modulation transfer function (MTF). The SFR algorithm can measure frequencies beyond the Nyquist frequency thanks to super-resolution, so it does provide useful information on aliasing and can provide modulation for frequencies between half Nyquist and Nyquist on all color channels of a color sensor with a Bayer pattern. The measurement process relies on a chart that is simple to manufacture: a straight transition from a bright reflectance to a dark one (black and white for instance), while a sine chart requires handling precisely shades of gray which can also create all sort of issues with printers that rely on half-toning. However, no technology can create a perfect edge, so it is important to assess the quality of the chart and understand how it affects the accuracy of the measurement. In this article, I describe a protocol to characterize the MTF of a slanted edge chart, using a high-resolution flatbed scanner. The main idea is to use the RAW output of the scanner as a high-resolution micro-densitometer, since the signal is linear it is suitable to measure the chart MTF using the SFR algorithm. The scanner needs to be calibrated in sharpness: the scanner MTF is measured with a calibrated sine chart and inverted to compensate for the modulation loss from the scanner. Then the true chart MTF is computed. This article compares measured MTF from commercial charts and charts printed on printers, and also compares how of the contrast of the edge (using different shades of gray) can affect the chart MTF

  4. Low fatness, reduced fat intake and adequate plasmatic concentrations of LDL-cholesterol are associated with high bone mineral density in women: a cross-sectional study with control group

    PubMed Central

    2012-01-01

    Background Several parameters are associated with high bone mineral density (BMD), such as overweight, black background, intense physical activity (PA), greater calcium intake and some medications. The objectives are to evaluate the prevalence and the main aspects associated with high BMD in healthy women. Methods After reviewing the database of approximately 21,500 BMD scans performed in the metropolitan area of São Paulo, Brazil, from June 2005 to October 2010, high BMD (over 1400 g/cm2 at lumbar spine and/or above 1200 g/cm2 at femoral neck) was found in 421 exams. Exclusion criteria were age below 30 or above 60 years, black ethnicity, pregnant or obese women, disease and/or medications known to interfere with bone metabolism. A total of 40 women with high BMD were included and matched with 40 healthy women with normal BMD, paired to weight, age, skin color and menopausal status. Medical history, food intake and PA were assessed through validated questionnaires. Body composition was evaluated through a GE-Lunar DPX MD + bone densitometer. Radiography of the thoracic and lumbar spine was carried out to exclude degenerative alterations or fractures. Biochemical parameters included both lipid and hormonal profiles, along with mineral and bone metabolism. Statistical analysis included parametric and nonparametric tests and linear regression models. P < 0.05 was considered significant. Results The mean age was 50.9 (8.3) years. There was no significant difference between groups in relation to PA, smoking, intake of calcium and vitamin D, as well as laboratory tests, except serum C-telopeptide of type I collagen (s-CTX), which was lower in the high BMD group (p = 0.04). In the final model of multivariate regression, a lower fat intake and body fatness as well a better profile of LDL-cholesterol predicted almost 35% of high BMD in women. (adjusted R2 = 0.347; p < 0.001). In addition, greater amounts of lean mass and higher IGF-1 serum concentrations played a

  5. Validation of Long Bone Mechanical Properties from Densitometry

    NASA Technical Reports Server (NTRS)

    Whalen, R.; Katz, B.; Cleek, T.; Hargens, Alan R. (Technical Monitor)

    1995-01-01

    The objective of this study was to assess whether cross-sectional areal properties, calculated from densitometry, correlate to the true flexural properties. Right and left male embalmed tibiae were used in the study. Prior to scanning, the proximal end of each tibia was potted in a fixture with registration pins, flushed thoroughly with water under pressure to remove trapped air, and then placed in a constant thickness water bath attached to a precision indexer. Two sets of three scans of the entire tibia were taken with an Hologic QDR 1000/W densitometer at rotations of 0, 45, and 90 degrees about the tibia long axis. An aluminum step phantom and a bone step phantom, machined from bovine cortical bone, were also in the bath and scanned separately. Pixel attenuation data from the two sets of scans were averaged to reduce noise. Pixel data from the high energy beam were then converted to equivalent thicknesses using calibration equations. Cross-sectional areal properties (centroid, principal area moments and principal angle) along the length were computed from the three registered scans using methods developed in our laboratory. Flexural rigidities. Four strain gages were bonded around the circumference of each of 5 cross-sections encompassing the entire diaphysis. A known transverse load was then applied to the distal end and the bone was rotated 360 degrees in eight increments of 45 degrees each. Strains from the eight orientations were analyzed along with the known applied bending moments at each section to compute section centroids, curvatures, principal flexural rigidities and principal angle. Reference axes between the two methods were maintained within +/- 0.5 degrees using an electronic inclinometer. Principal angles (flexural - areal) differed by -2.0 +/- 4.0 degrees, and 1.0 +/- 2.5 degrees for the right and left tibia, respectively. Section principal flexural rigidities were highly correlated to principal areal moments (right: r(sup 2)= 0.997; left: r

  6. [Sufficiency with water-soluble vitamins and state of bone in pregnant women].

    PubMed

    Vrzhesinskaya, O A; Pereverzeva, O G; Gmoshinskaya, M V; Kodentsova, V M; Safronova, A I; Korosteleva, M M; Aleshina, I V; Fandeeva, T A

    2015-01-01

    Vitamin status and bone strength have been estimated in 91 pregnant women (29.3 ± 4.6 years old) from Moscow by non-invasive methods. Sufficiency with vitamins C, B2, B6 has been evaluated by morning urinary excretion of ascorbic acid, riboflavin and 4-piridoxic acid determined by visual titration and fluorimetric methods. The rate of bone resorption has been measured by the ratio of urinary calcium and creatinine, determined by complexometric titration and spectrophotometrically. The study of the bone strength has been conducted using an ultrasonic densitometer (the speed of the ultrasonic waves along the cortical layer). The lack of vitamin C was found in 20.4% .of the women surveyed, vitamin B2--in 27.4%. Vitamin B6 deficiency was detected most frequently (90%). Excretion of vitamins B2 and B6 in women in the third trimester of pregnancy was lower as compared with the women in the first and second trimester. In 53.3% of the women surveyed an increase in urinary excretion of calcium per creatinine has been observed. Excretion of group B vitamins (especially vitamin B6, 1.75 fold, p < 0.05) in women taking vitamin supplements was higher compared to non-taking vitamins that indicates the better sufficiency of the organism with these vitamins. Among women who took vitamin complexes, inadequate supply with water-soluble vitamins C, B2 and B6 was detected less frequently (the difference was significant for vitamin B2) than among women who did not intake vitamin complexes (in 11.9, 27.7 and 42.4% vs 16.1, 54.8 and 48.8 %). The rate of bone resorption (Ca/creatinine) in women taking vitamins was smaller (0.19 ± 0.09 vs 0.24 ± 0.14, p > 0.05). Ca/creatinine ratio was within normal range in 40% of women who intake vitamins, while in women not taking vitamins--only in 22.2%; this value exceeded the upper limit of norm in the rest. The strength of bone was broken in women in the second and third trimester of pregnancy, having worse supply of vitamins. The percentage of

  7. COMPUTATIONAL AND EXPERIMENTAL MODELING OF SLURRY BUBBLE COLUMN REACTORS

    SciTech Connect

    Paul C.K. Lam; Isaac K. Gamwo; Dimitri Gidaspow

    2002-05-01

    The objective of this study was to develop a predictive experimentally verified computational fluid dynamics (CFD) model for gas-liquid-solid flow. A three dimensional transient computer code for the coupled Navier-Stokes equations for each phase was developed and is appended in this report. The principal input into the model is the viscosity of the particulate phase which was determined from a measurement of the random kinetic energy of the 800 micron glass beads and a Brookfield viscometer. The details are presented in the attached paper titled ''CFD Simulation of Flow and Turbulence in a Slurry Bubble Column''. This phase of the work is in press in a referred journal (AIChE Journal, 2002) and was presented at the Fourth International Conference on Multiphase Flow (ICMF 2001) in New Orleans, May 27-June 1, 2001 (Paper No. 909). The computed time averaged particle velocities and concentrations agree with Particle Image Velocimetry (PIV) measurements of velocities and concentrations, obtained using a combination of gamma-ray and X-ray densitometers, in a slurry bubble column, operated in the bubbly-coalesced fluidization regime with continuous flow of water. Both the experiment and the simulation show a down-flow of particles in the center of the column and up-flow near the walls and nearly uniform particle concentration. Normal and shear Reynolds stresses were constructed from the computed instantaneous particle velocities. The PIV measurement and the simulation produced instantaneous particle velocities. The PIV measurement and the simulation produced similar nearly flat horizontal profiles of turbulent kinetic energy of particles. To better understand turbulence we studied fluidization in a liquid-solid bed. This work was also presented at the Fourth International Conference on Multiphase Flow (ICMF 2001, Paper No. 910). To understand turbulence in risers, measurements were done in the IIT riser with 530 micron glass beads using a PIV technique. This report

  8. Intra-annual variability of anatomical structure and δ13C values within tree rings of spruce and pine in alpine, temperate and boreal Europe

    PubMed Central

    Vaganov, Eugene A.; Skomarkova, Marina V.; Knohl, Alexander; Brand, Willi A.; Roscher, Christiane

    2009-01-01

    Tree-ring width, wood density, anatomical structure and 13C/12C ratios expressed as δ13C-values of whole wood of Picea abies were investigated for trees growing in closed canopy forest stands. Samples were collected from the alpine Renon site in North Italy, the lowland Hainich site in Central Germany and the boreal Flakaliden site in North Sweden. In addition, Pinus cembra was studied at the alpine site and Pinus sylvestris at the boreal site. The density profiles of tree rings were measured using the DENDRO-2003 densitometer, δ13C was measured using high-resolution laser-ablation-combustion-gas chromatography-infra-red mass spectrometry and anatomical characteristics of tree rings (tracheid diameter, cell-wall thickness, cell-wall area and cell-lumen area) were measured using an image analyzer. Based on long-term statistics, climatic variables, such as temperature, precipitation, solar radiation and vapor pressure deficit, explained <20% of the variation in tree-ring width and wood density over consecutive years, while 29–58% of the variation in tree-ring width were explained by autocorrelation between tree rings. An intensive study of tree rings between 1999 and 2003 revealed that tree ring width and δ13C-values of whole wood were significantly correlated with length of the growing season, net radiation and vapor pressure deficit. The δ13C-values were not correlated with precipitation or temperature. A highly significant correlation was also found between δ13C of the early wood of one year and the late wood of the previous year, indicating a carry-over effect of the growing conditions of the previous season on current wood production. This latter effect may explain the high autocorrelation of long-term tree-ring statistics. The pattern, however, was complex, showing stepwise decreases as well as stepwise increases in the δ13C between late wood and early wood. The results are interpreted in the context of the biochemistry of wood formation and its linkage

  9. White spotting variant (Wv) mouse as an experimental model for ovarian aging and menopausal biology

    PubMed Central

    Smith, Elizabeth R.; Yeasky, Toni; Wei, Jain Qin; Miki, Roberto A.; Cai, Kathy Q.; Smedberg, Jennifer L.; Yang, Wan-Lin; Xu, Xiang-Xi

    2011-01-01

    Objective Menopause is a unique phenomenon in modern women, as most mammalian species possess a reproductive period comparable to their lifespan. Menopause is caused by the depletion of germ cell-containing ovarian follicles, and in laboratory studies is usually modeled in animals in which the ovarian function is removed by ovariectomy or chemical poisoning of the germ cells. Our objective was to explore and characterize the white spotting variant (Wv) mice that have reduced ovarian germ cell abundance, a result of a point mutation in the c-kit gene that decreases the kinase activity, as a genetic model for use in menopausal studies. Methods Physiological and morphological features associated with menopause were determined in female Wv/Wv mice compared to age-matched wildtype controls. Immunohistochemistry was used to evaluate the presence and number of follicles in paraffin-embedded ovaries. Bone density and body composition were evaluated using the PIXImus X-ray densitometer, and lipids, calcium, and hormone levels were determined in serum using antigen-specific EIAs. Heart and body weight were measured, and cardiac function was evaluated by transthoracic echocardiography. Results The ovaries of the Wv/Wv females have a greatly reduced number of normal germ cells at birth compared to wildtype mice. The remaining follicles are depleted by around 2 months, and the ovaries develop benign epithelial lesions that resemble morphological changes that occur during ovarian aging, whereas a normal mouse ovary has numerous follicles at all stages of development and retains some follicles even in advanced age. Wv mice have elevated plasma gonadotrophins and reduced estrogen and progesterone levels, a significant reduction in bone mass density, and elevated serum cholesterol and lipoprotein levels. Moreover, the Wv female mice have enlarged hearts and reduced cardiac function. Conclusions The reduction of c-kit activity in Wv mice leads to a substantially diminished

  10. Evaluation of the Sub-Channel Code COBRA-TF for Prediction of BWR Fuel Assembly Void Fraction Distribution

    SciTech Connect

    Aydogan, Fatih; Hochreiter, Lawrence E.; Ivanov, Kostadin; Rhee, Gene; Sartori, Enrico

    2006-07-01

    Good quality experimental data is needed to refine the thermal hydraulic models for the prediction of rod bundle void distribution and critical heat flux (CHF) or dry-out. The Nuclear Power Engineering Corporation (NUPEC) has provided a valuable database to evaluate the thermal hydraulic codes [1]. Part of this database was selected for the NUPEC BWR Full-size Fine-Mesh Bundle Tests (BFBT) benchmark sponsored by US NRC, METI-Japan, NEA/OECD and Nuclear Engineering Program of the Pennsylvania State University (PSU). Twenty-five organizations from ten countries have confirmed their intention to participate and will provide code predictions to be compared to the measured data for a series of defined exercises within the framework of the BFBT benchmark. This benchmark data includes both the fine-mesh high quality sub-channel void fraction and critical power data. Using a full BWR rod bundle test facility, the void distribution was measured at mesh sizes smaller than the sub-channel by using a state-of-the-art computer tomography (CT) technology [1]. Experiments were performed for different pressures, flow rates, exit qualities, inlet sub-cooling, power distributions, spacer types and assembly designs. There are microscopic and sub-channel averaged void fraction data from the CT scanner at the bundle exit as well as X-ray densitometer void distribution data at different elevation levels in the rod bundle. Each sub-channel's loss coefficient was calculated with using the Rehme method [2,3], and a COBRA-TF sub-channel model was developed for the NUPEC facility. The BWR assembly that was modeled with COBRA-TF includes two water rods at the center. The predicted sub-channel void fraction values from COBRA-TF are compared with the bundle exit void fraction values measured using the CT-scanner void fraction from the BFBT benchmark data. Different plots are used to examine the code prediction of the void distribution at a sub-channel level for the different sub-channels within

  11. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-04-30

    Experiments on the flow loop are continuing. Improvements to the software for data acquisition are being made as additional experience with three-phase flow is gained. Modifications are being made to the Cuttings Injection System in order to improve control and the precision of cuttings injection. The design details for a drill-pipe Rotation System have been completed. A US Patent was filed on October 28, 2002 for a new design for an instrument that can generate a variety of foams under elevated pressures and temperatures and then transfer the test foam to a viscometer for measurements of viscosity. Theoretical analyses of cuttings transport phenomena based on a layered model is under development. Calibrations of two nuclear densitometers have been completed. Baseline tests have been run to determine wall roughness in the 4 different tests sections (i.e. 2-in, 3-in, 4-in pipes and 5.76-in by 3.5-in annulus) of the flow loop. Tests have also been conducted with aerated fluids at EPET conditions. Preliminary experiments on the two candidate aqueous foam formulations were conducted which included rheological tests of the base fluid and foam stability reports. These were conducted after acceptance of the proposal on the Study of Cuttings Transport with Foam Under Elevated Pressure and Elevated Temperature Conditions. Preparation of a test matrix for cuttings-transport experiments with foam in the ACTF is also under way. A controller for instrumentation to measure cuttings concentration and distribution has been designed that can control four transceivers at a time. A prototype of the control circuit board was built and tested. Tests showed that there was a problem with radiated noise. AN improved circuit board was designed and sent to an external expert to verify the new design. The new board is being fabricated and will first be tested with static water and gravel in an annulus at elevated temperatures. A series of viscometer tests to measure foam properties have

  12. Utilization of DXA Bone Mineral Densitometry in Ontario

    PubMed Central

    2006-01-01

    Executive Summary Issue Systematic reviews and analyses of administrative data were performed to determine the appropriate use of bone mineral density (BMD) assessments using dual energy x-ray absorptiometry (DXA), and the associated trends in wrist and hip fractures in Ontario. Background Dual Energy X-ray Absorptiometry Bone Mineral Density Assessment Dual energy x-ray absorptiometry bone densitometers measure bone density based on differential absorption of 2 x-ray beams by bone and soft tissues. It is the gold standard for detecting and diagnosing osteoporosis, a systemic disease characterized by low bone density and altered bone structure, resulting in low bone strength and increased risk of fractures. The test is fast (approximately 10 minutes) and accurate (exceeds 90% at the hip), with low radiation (1/3 to 1/5 of that from a chest x-ray). DXA densitometers are licensed as Class 3 medical devices in Canada. The World Health Organization has established criteria for osteoporosis and osteopenia based on DXA BMD measurements: osteoporosis is defined as a BMD that is >2.5 standard deviations below the mean BMD for normal young adults (i.e. T-score <–2.5), while osteopenia is defined as BMD that is more than 1 standard deviation but less than 2.5 standard deviation below the mean for normal young adults (i.e. T-score< –1 & ≥–2.5). DXA densitometry is presently an insured health service in Ontario. Clinical Need   Burden of Disease The Canadian Multicenter Osteoporosis Study (CaMos) found that 16% of Canadian women and 6.6% of Canadian men have osteoporosis based on the WHO criteria, with prevalence increasing with age. Osteopenia was found in 49.6% of Canadian women and 39% of Canadian men. In Ontario, it is estimated that nearly 530,000 Ontarians have some degrees of osteoporosis. Osteoporosis-related fragility fractures occur most often in the wrist, femur and pelvis. These fractures, particularly those in the hip, are associated with increased

  13. [Role and functional spectrum of HPTLC in a hospital pharmaceutical quality control program].

    PubMed

    Bourget, P; Perello, L; Demirdjian, S

    2001-02-01

    As part of the development of a quality assurance program (QAP), a high performance thin layer chromatography (HPTLC) analysis unit was installed in the pharmacy department at Gustave-Roussy. The HPTLC-CAMAG consists of: 1) an HPTLC-Vario development chamber for optimization of the mobile phases; 2) TLC Sampler III automated sample applicators; 3) solid teflon migration chambers, i.e., horizontal tanks that enable separation to be carried out either in sandwich or in saturation mode; 4) a TLC Scanner 3 densitometer controlled by CATS 4 software; and 5) a Pentium MMX 233 MHz personal computer with an external backup unit. HPTLC quantitative and qualitative analysis has now reached a remarkably high level of development and performance. The samples (aqueous or non-aqueous solutions) that are to be processed are automatically applied by spraying (50-300 nl) in calibrated bands of a few mm (with up to 64 3-mm bands per 10 x 20 cm plate) on high-performance stationary phases and of wide technological diversity. The chromatogram is obtained in 10 min, and run over a migration pathway of 5-6 cm. The plates are read by absorption-reflection or fluorescence-reflection at an ad hoc wavelength (190-800 nm), then the peak areas which have been scanned are calculated by the trapezoid method. The calibration curves are generated by Michaelis-Menten non-linear regression, and validated by internal quality control. The analytical yield is high, i.e., up to 50 assays and 250 determinations per day. HPTLC analysis covers a wide functional range, and can be used in the following ways: 1) as a teaching tool for separative analysis and GLP; 2) it is an invaluable method for the optimization of mobile phases and for the determination of absorption spectra and absorption maxima, with a view to developing HPLC methods in complex matrices; 3) it provides major support for post-production quality control of prescribed hospital preparations of all types, e.g., those connected with parenteral

  14. New Carriers and Sensors for Robotic Planetary Exploration

    NASA Astrophysics Data System (ADS)

    Romstedt, J.; Schiele, A.; Boudin, N.; Coste, P.; Lindner, R.

    performance. An alternative payload element for the payload cabin is an extremely small Laser Mass Spectrometer (LMS). A breadboard of this instrument is currently part of an extensive 1 test and evaluation campaign. Also this instrument will be re-designed to fit into the Nanokhod modular payload suite. The Instrumented Mole System (IMS) is based on a device that penetrates regolith down to a depth of 5 meter. The Heat Flow and Physical Properties Package (HP3 ) demonstrates that a scientifically meaningful payload can be integrated into the payload compartment. This package comprises an active temperature measurement module, a densitometer to determine the density of the penetrated regolith and a device to determine the precise location of the mole. An alternative instrument is based on an Attenuated Total Reflection (ATR) infrared spectrometer. It will observe and analyse through a window all material adjacent to the hull of the payload compartment within the penetration hole. A newly implemented project is the design and fabrication of a melting probe. This probe enables the subsurface exploration of icy layers. It will be capable to carry scientific instrumentation into depth and decipher the stratigraphy of ice and dust deposition on planetary bodies. The overall goal of all support activities is to analyse, design and built all critical components of a technologies which has no space application so far. Once all technical hurdles have been overcome by the breadboard development, a given instrumentation can rapidly be inserted into a flight model programme. 2

  15. Damping and fluidelastic instability in two-phase cross-flow heat exchanger tube arrays

    NASA Astrophysics Data System (ADS)

    Moran, Joaquin E.

    An experimental study was conducted to investigate damping and fluidelastic instability in tube arrays subjected to two-phase cross-flow. The purpose of this research was to improve our understanding of these phenomena and how they are affected by void fraction and flow regime. The model tube bundle had 10 cantilevered tubes in a parallel-triangular configuration, with a pitch ratio of 1.49. The two-phase flow loop used in this research utilized Refrigerant 11 as the working fluid, which better models steam-water than air-water mixtures in terms of vapour-liquid mass ratio as well as permitting phase changes due to pressure fluctuations. The void fraction was measured using a gamma densitometer, introducing an improvement over the Homogeneous Equilibrium Model (HEM) in terms of void fraction, density and velocity predictions. Three different damping measurement methodologies were implemented and compared in order to obtain a more reliable damping estimate. The methods were the traditionally used half-power bandwidth, the logarithmic decrement and an exponential fitting to the tube decay response. The decay trace was obtained by "plucking" the monitored tube from outside the test section using a novel technique, in which a pair of electromagnets changed their polarity at the natural frequency of the tube to produce resonance. The experiments showed that the half-power bandwidth produces higher damping values than the other two methods. The primary difference between the methods is caused by tube frequency shifting, triggered by fluctuations in the added mass and coupling between the tubes, which depend on void fraction and flow regime. The exponential fitting proved to be the more consistent and reliable approach to estimating damping. In order to examine the relationship between the damping ratio and mass flux, the former was plotted as a function of void fraction and pitch mass flux in an iso-contour plot. The results showed that damping is not independent of mass

  16. Nuclear DNA Amounts in Angiosperms: Progress, Problems and Prospects

    PubMed Central

    BENNETT, M. D.; LEITCH, I. J.

    2005-01-01

    densitometers used to measure DNA C-values proved less serious than feared, owing to the development of relatively inexpensive flow cytometers and computer-based image analysis systems. New uses of the term genome (e.g. in ‘complete’ genome sequencing) can cause confusion. The Arabidopsis Genome Initiative C-value for Arabidopsis thaliana (125 Mb) was a gross underestimate, and an exact C-value based on genome sequencing alone is unlikely to be obtained soon for any angiosperm. Lack of this expected benchmark poses a quandary as to what to use as the basal calibration standard for angiosperms. The next decade offers exciting prospects for angiosperm genome size research. The database (http://www.kew.org/cval/homepage) should become sufficiently representative of the global flora to answer most questions without needing new estimations. DNA amount variation will remain a key interest as an integrated strand of holistic genomics. PMID:15596457

  17. COLD TEST LOOP INTEGRATED TEST LOOP RESULTS

    SciTech Connect

    Abraham, TJ

    2003-10-22

    A testing facility (Cold Test Loop) was constructed and operated to demonstrate the efficacy of the Accelerated Waste Retrieval (AWR) Project's planned sluicing approach to the remediation of Silos 1 and 2 at the Fernald Environmental Management Project near Cincinnati, Ohio. The two silos contain almost 10,000 tons of radium-bearing low-level waste, which consists primarily of solids of raffinates from processing performed on ores from the Democratic Republic of Congo (commonly referred to as ''Belgium Congo ores'') for the recovery of uranium. These silos are 80 ft in diameter, 36 ft high to the center of the dome, and 26.75 ft to the top of the vertical side walls. The test facility contained two test systems, each designed for a specific purpose. The first system, the Integrated Test Loop (ITL), a near-full-scale plant including the actual equipment to be installed at the Fernald Site, was designed to demonstrate the sluicing operation and confirm the selection of a slurry pump, the optimal sluicing nozzle operation, and the preliminary design material balance. The second system, the Component Test Loop (CTL), was designed to evaluate many of the key individual components of the waste retrieval system over an extended run. The major results of the initial testing performed during July and August 2002 confirmed that the AWR approach to sluicing was feasible. The ITL testing confirmed the following: (1) The selected slurry pump (Hazleton 3-20 type SHW) performed well and is suitable for AWR application. However, the pump's motor should be upgraded to a 200-hp model and be driven by a 150-hp variable-frequency drive (VFD). A 200-hp VFD is not much more expensive and would allow the pump to operate at full speed. (2) The best nozzle performance was achieved by using 15/16-in. nozzles operated alternately. This configuration appeared to most effectively mine the surrogate. (3) The Solartron densitometer, which was tested as an alternative mass flow measurement