Sample records for syringe calibration factors

  1. A portable volume/flow calibrating syringe.

    PubMed

    Shigeoka, J W; Gardner, R M; Barkman, H W

    1982-11-01

    Two samples of a manual 3 L calibrating syringe which displays an electronically calculated FEF25-75% were evaluated to determine its suitability as a flow calibrator were evaluated. Room air was discharged into a manual spirometer system known to be accurate. The calibrator-determined values correlated very closely with the spirometer values over an FEF25-75% range of 0.4 to 9 L/sec. The differences between calibrator and spirometer FEF25-75% values were small (mean +/- 1 percent, greatest 3.7 percent) and of little importance clinically. This portable, simple to operate calibrating syringe provides accurate FEF25-75% and volume values. By adding flow calibrating capability to a recommended standard volume calibrating syringe, it will facilitate the routine calibration of spirometers in the laboratory and in the field. Since it uses displaced air, it can be used at altitude and with flow measuring instruments without the correction required for calibrators using CO2 cartridges. PMID:7128227

  2. Demographic, Risk, and Spatial Factors Associated With Over-the-Counter Syringe Purchase Among Injection Drug Users

    PubMed Central

    Stopka, Thomas J.; Lutnick, Alexandra; Wenger, Lynn D.; DeRiemer, Kathryn; Geraghty, Estella M.; Kral, Alex H.

    2012-01-01

    Since 2005, California law allowed over-the-counter (OTC) syringe sales pending local authorization. Although pharmacy sales of OTC syringes are associated with reduced injection-mediated risks and decreases in human immunodeficiency virus infection rates, little is known about the factors associated with syringe purchase among injection drug users (IDUs). Using a cross-sectional design, the authors applied targeted sampling to collect quantitative survey data from IDUs (n = 563) recruited in San Francisco, California, during 2008. They also compiled a comprehensive list of retail pharmacies, their location, and whether they sell OTC syringes. They used a novel combination of geographic information system and statistical analyses to determine the demographic, behavioral, and spatial factors associated with OTC syringe purchase by IDUs. In multivariate analyses, age, race, injection frequency, the type of drug injected, and the source of syringe supply were independently associated with OTC syringe purchases. Notably, the prevalence of OTC syringe purchase was 53% lower among African-American IDUs (adjusted prevalence ratio = 0.47, 95% confidence interval: 0.33, 0.67) and higher among injectors of methamphetamine (adjusted prevalence ratio = 1.35, 95% confidence interval: 1.07, 1.70). Two neighborhoods with high densities of IDUs had limited access to OTC syringes. Increased access to OTC syringes would potentially prevent blood-borne infectious diseases among IDUs. PMID:22562660

  3. Risk Factors for Nonfatal Overdose at Seattle-Area Syringe Exchanges

    Microsoft Academic Search

    Lindsay M. Jenkins; Caleb J. Banta-Green; Charles Maynard; Susan Kingston; Michael Hanrahan; Joseph O. Merrill; Phillip O. Coffin

    2011-01-01

    Opioid-involved overdose deaths are on the rise, both nationwide and in the state of Washington. In a survey of 443 participants\\u000a at syringe exchanges in Seattle, Washington, 16% had overdosed in the last year. Several factors were significantly associated\\u000a in bivariate analysis: lack of permanent housing; incarceration of five or more days in the past year; gender of sex partners;

  4. Factors associated with presence of pharmacies and pharmacies that sell syringes over-the-counter in Los Angeles County.

    PubMed

    Stopka, Thomas J; Geraghty, Estella M; Azari, Rahman; Gold, Ellen B; Deriemer, Kathryn

    2013-12-01

    Community pharmacies serve as key locations for public health services including interventions to enhance the availability of syringes sold over-the-counter (OTC), an important strategy to prevent injection-mediated HIV transmission. Little is known about the community characteristics associated with the availability of pharmacies and pharmacies that sell syringes OTC. We conducted multivariable regression analyses to determine whether the sociodemographic characteristics of census tract residents were associated with pharmacy presence in Los Angeles (LA) County during 2008. Using a geographic information system, we conducted hot-spot analyses to identify clusters of pharmacies, OTC syringe-selling pharmacies, sociodemographic variables, and their relationships. For LA County census tracts (N?=?2,054), population size (adjusted odds ratio [AOR], 1.22; 95 % confidence interval [CI], 1.16, 1.28), median age of residents (AOR, 1.03; 95 % CI, 1.01, 1.05), and the percent of households receiving public assistance (AOR, 0.97; 95 % CI, 0.94, 0.99) were independently associated with the presence of all pharmacies. Only 12 % of census tracts had at least one OTC syringe-selling pharmacy and sociodemographic variables were not independently associated with the presence of OTC syringe-selling pharmacies. Clusters of pharmacies (p?factors associated with the presence of community pharmacies and pharmacies that participate in OTC syringe sales. PMID:23567984

  5. Syringe possession arrests are associated with receptive syringe sharing in two Mexico-US border cities

    PubMed Central

    Pollini, Robin A.; Brouwer, Kimberly C.; Lozada, Remedios M.; Ramos, Rebeca; Cruz, Michelle F.; Magis-Rodriguez, Carlos; Case, Patricia; Burris, Scott; Pu, Minya; Frost, Simon D. W.; Palinkas, Lawrence A.; Miller, Cari; Strathdee, Steffanie A.

    2008-01-01

    Aims To identify factors associated with receptive syringe sharing among injection drug users (IDUs) and elucidate the association between syringe possession arrests and syringe sharing. Design Cross-sectional study. Setting Mexican border cities of Tijuana, Baja California and Ciudad Juarez, Chihuahua. Participants IDUs in Tijuana (n = 222) and Ciudad Juarez (n = 206) were recruited using respondent-driven sampling (RDS). IDUs were ?18 years and had injected illicit drugs in the past month. Measurements An interviewer-administered survey was used to collect quantitative data on socio-demographic, behavioral and contextual characteristics, including self-reported syringe sharing and arrests for syringe possession. Associations with receptive syringe sharing were investigated using logistic regression with RDS adjustment. Findings Overall, 48% of participants reported ever being arrested for carrying an unused/sterile syringe, even though syringe purchase and possession is legal in Mexico. Arrest for possessing unused/sterile syringes was associated independently with receptive syringe sharing [adjusted odds ratio (AOR) = 2.05; 95% confidence interval (CI): 1.26, 3.35], as was injecting in a shooting gallery (AOR = 3.60; 95% CI: 2.21, 5.87), injecting in the street (AOR = 2.05; 95% CI: 1.18, 3.54) and injecting methamphetamine (AOR = 2.77; 95% CI: 1.41, 5.47) or cocaine (AOR = 1.96; 95% CI: 1.15, 3.36). More than half of participants (57%) had been arrested for possessing a used syringe; in a second model, arrest for used syringe possession was also associated independently with receptive sharing (AOR = 2.87; 95% CI: 1.76, 4.69). Conclusions We documented high levels of syringe-related arrests in two Mexican–US border cities and an independent association between these arrests and risky injection practices. Public health collaborations with law enforcement to modify the risk environment in which drug use occurs are essential to facilitate safer injection practices. PMID:18028520

  6. Patient Safety Threat - Syringe Reuse

    MedlinePLUS

    ... About CDC.gov . Injection Safety Share Compartir A Patient Safety Threat – Syringe Reuse Important Information! Please read ... due to syringe reuse by your healthcare provider. Patients need to be aware of a very serious ...

  7. The Tacoma Syringe Exchange.

    PubMed

    Hagan, H; Des Jarlais, D C; Purchase, D; Reid, T; Friedman, S R

    1991-01-01

    For over a year, the Tacoma Syringe Exchange has been operating in spite of existing drug paraphernalia laws. One hundred fifty-four subjects have been interviewed regarding drug injection practices for the month prior to first use of the exchange and for the most recent month since using the exchange. Statistically significant reductions in mean frequency of obtaining used syringes, and in mean rate of passing on used syringes, have been reported. Mean number of times bleach was used to disinfect contaminated syringes has risen. The exchange continues to attract mainly men, median age 35, with a long history of injection. No differences have been observed in mean number of injections per month. In order to increase utilization, new sites are planned, but expansion has been hampered by a series of legal problems. Since the exchange draws many difficult to reach individuals, it is an important location for STD screening and drug treatment recruitment. Documentation of participation patterns and barriers to exchange use, and effects upon HIV serological status are recommended. PMID:1777501

  8. Calibration factors for the SNOOPY NP-100 neutron dosimeter

    NASA Astrophysics Data System (ADS)

    Moscu, D. F.; McNeill, F. E.; Chase, J.

    2007-10-01

    Within CANDU nuclear power facilities, only a small fraction of workers are exposed to neutron radiation. For these individuals, roughly 4.5% of the total radiation equivalent dose is the result of exposure to neutrons. When this figure is considered across all workers receiving external exposure of any kind, only 0.25% of the total radiation equivalent dose is the result of exposure to neutrons. At many facilities, the NP-100 neutron dosimeter, manufactured by Canberra Industries Incorporated, is employed in both direct and indirect dosimetry methods. Also known as "SNOOPY", these detectors undergo calibration, which results in a calibration factor relating the neutron count rate to the ambient dose equivalent rate, using a standard Am-Be neutron source. Using measurements presented in a technical note, readings from the dosimeter for six different neutron fields in six source-detector orientations were used, to determine a calibration factor for each of these sources. The calibration factor depends on the neutron energy spectrum and the radiation weighting factor to link neutron fluence to equivalent dose. Although the neutron energy spectra measured in the CANDU workplace are quite different than that of the Am-Be calibration source, the calibration factor remains constant - within acceptable limits - regardless of the neutron source used in the calibration; for the specified calibration orientation and current radiation weighting factors. However, changing the value of the radiation weighting factors would result in changes to the calibration factor. In the event of changes to the radiation weighting factors, it will be necessary to assess whether a change to the calibration process or resulting calibration factor is warranted.

  9. Gas ampoule-syringe

    DOEpatents

    Gay, Don D. (Aiken, SC)

    1986-01-01

    A gas ampoule for the shipment and delivery of radioactive gases. The gas ampoule having a glass tube with serum bottle stopper on one end and a plunger tip in the opposite end all fitting in a larger plastic tube threaded on each end with absorbent between the tubes, is seated onto the internal needle assembly via a bushing associated with the plunger and locked into the syringe barrel via barrel-bushing locking caps. The design practically eliminates the possibility of personnel contamination due to an inadvertent exposure of such personnel to the contained radioactive gas.

  10. Gas ampoule-syringe

    DOEpatents

    Gay, D.D.

    1985-02-02

    A gas ampoule for the shipment and delivery of radioactive gases. The gas ampoule having a glass tube with serum bottle stopper on one and a plunger tip in the opposite end all fitting in a larger plastic tube threaded on each end with absorbent between the tubes, is seated onto the internal needle assembly via a bushing associated with the plunger and locked into the syringe barrel via barrel-bushing locking caps. The design practically eliminates the possibility of personnel contamination due to an inadvertent exposure of such personnel to the contained radioactive gas.

  11. Deviation in the predefined calibration factors of the dose calibrators and the associated inaccuracy in the radioactivity measurements of beta-gamma emitters

    PubMed Central

    Sharma, Sarika; Singh, Baljinder; Koul, Ashwani; Mittal, Bhagwant Rai

    2015-01-01

    Aim: To determine whether the predefined calibration factors of the dose calibrators can provide accurate radioactivity measurements of beta-gamma emitters used in routine therapeutic nuclear medicine procedures. Materials and Methods: Two models of dose calibrators were used in the present study for radioactivity measurements of 153Sm ethylenediamine-N, N, N’, N’-tetrakis methylene phosphonic acid (EDTMP) and 177Lu (EDTMP). A known (precalibrated) activity of each of the two beta emitters received by us from our National Supplier for administration to the patients with extensive bony metastases for bone pain palliation, was used for experiments. Results: When we used the manufacturers’ provided dial setting of 450 × 10, each of the dose calibrators underestimated the radioactivity of 177Lu by about 9.0%. Dial settings of 403 × 10 and 408 × 10 for 177Lu on CRC-15R and CRC-ultra dose calibrators respectively were calculated experimentally using an iterative approach. The radioactivity measurements made at these settings provided an excellent agreement with the specified values. Likewise, a dial setting of 230 for each of the two dose calibrators was calculated for 153Sm, which provided a good agreement between the experimentally derived radioactivity values and the certified values. A deviation of ± 5.0% was observed when radioactivity of 177Lu and 153Sm was measured over a wide range (4.0 MBq to 2.1 GBq) for time intervals equivalent to 4.5 half-lives of each of the two radionuclides. A deviation of ± 5% was observed when radioactivity was counted in different dilution volumes and in syringes of varying size. Conclusion: These variations could lead to a cumulative error of about 20.0% toward the inaccuracy in the radioactivity measurements of the beta-gamma emitters and thus predefined calibration factors of the dose calibrators may require experimental re-setting of these parameters and periodic checking to provide accurate radioactivity estimates of beta-gamma emitters in a given clinical setting.

  12. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 2012-04-01 false Piston syringe. 880.5860 Section 880.5860...Personal Use Therapeutic Devices § 880.5860 Piston syringe. (a) Identification. A piston syringe is a device intended for...

  13. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 2014-04-01 false Piston syringe. 880.5860 Section 880.5860...Personal Use Therapeutic Devices § 880.5860 Piston syringe. (a) Identification. A piston syringe is a device intended for...

  14. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 2011-04-01 false Piston syringe. 880.5860 Section 880.5860...Personal Use Therapeutic Devices § 880.5860 Piston syringe. (a) Identification. A piston syringe is a device intended for...

  15. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 2013-04-01 false Piston syringe. 880.5860 Section 880.5860...Personal Use Therapeutic Devices § 880.5860 Piston syringe. (a) Identification. A piston syringe is a device intended for...

  16. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Piston syringe. 880.5860 Section 880...Devices § 880.5860 Piston syringe. (a) Identification. A piston syringe is a device intended for...hollow barrel and a movable plunger. At one end of the...

  17. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...The device consists of a metal syringe body into which a disposable...After attaching a needle to the syringe body and activating the carpule by partially inserting the plunger on the syringe, the device is used to...

  18. Syringe thermodynamics: The many uses of a glass syringe

    NASA Astrophysics Data System (ADS)

    Jackson, David P.; Laws, Priscilla W.

    2006-02-01

    Glass syringes have precision fit low-friction pistons and are relatively inexpensive, which makes them an ideal tool for studying the thermal behavior of gases. The glass syringe is used to construct a thermometer, a miniature hydraulic press, and a working heat engine. Concepts illuminated by these experiments include temperature, pressure, the ideal gas law, work, internal energy, and the first law of thermodynamics.

  19. Experiments with Disposable Hypodermic Syringes.

    ERIC Educational Resources Information Center

    Clayton, G. T.; And Others

    1988-01-01

    Lists five experiments or demonstrations involving hypodermic syringes. The titles of experiments are Boyle's Law, Charles' Law, Atmospheric Pressure, Expansion of Gases, and Boiling at Reduced Pressure. Provides a list of materials, the typical data, and graphs where appropriate. (YP)

  20. Calibration of Gyros with Temperature Dependent Scale Factors

    NASA Technical Reports Server (NTRS)

    Belur, Sheela V.; Harman, Richard

    2001-01-01

    The general problem of gyro calibration can be stated as the estimation of the scale factors, misalignments, and drift-rate biases of the gyro using the on-orbit sensor measurements. These gyro parameters have been traditionally treated as temperature-independent in the operational flight dynamics ground systems at NASA Goddard Space Flight Center (GSFC), a scenario which has been successfully applied in the gyro calibration of a large number of missions. A significant departure from this is the Microwave Anisotropy Probe (MAP) mission where, due to the high thermal variations expected during the mission phase, it is necessary to model the scale factors as functions of temperature. This paper addresses the issue of gyro calibration for the MAP gyro model using a manufacturer-supplied model of the variation of scale factors with temperature. The problem is formulated as a least squares problem and solved using the Levenberg-Marquardt algorithm in the MATLAB(R) library function NLSQ. The algorithm was tested on simulated data with Gaussian noise for the quaternions as well as the gyro rates and was found to consistently converge close to the true values. Significant improvement in accuracy was noticed due to the estimation of the temperature-dependent scale factors as against constant scale factors.

  1. jasonSWIR Calibration of Spectralon Reflectance Factor

    NASA Technical Reports Server (NTRS)

    Georgiev, Georgi T.; Butler, James J.; Cooksey, Cahterine; Ding, Leibo; Thome, Kurtis J.

    2011-01-01

    Satellite instruments operating in the reflective solar wavelength region require accurate and precise determination of the Bidirectional Reflectance Factor (BRF) of laboratory-based diffusers used in their pre-flight and on-orbit radiometric calibrations. BRF measurements are required throughout the reflected-solar spectrum from the ultraviolet through the shortwave infrared. Spectralon diffusers are commonly used as a reflectance standard for bidirectional and hemispherical geometries. The Diffuser Calibration Laboratory (DCaL) at NASA's Goddard Space Flight Center is a secondary calibration facility with reflectance measurements traceable to those made by the Spectral Tri-function Automated Reference Reflectometer (STARR) facility at the National Institute of Standards and Technology (NIST). For more than two decades, the DCaL has provided numerous NASA projects with BRF data in the ultraviolet (UV), visible (VIS) and the Near infraRed (NIR) spectral regions. Presented in this paper are measurements of BRF from 1475nm to 1625nm obtained using an indium gallium arsenide detector and a tunable coherent light source. The sample was a 2 inch diameter, 99% white Spectralon target. The BRF results are discussed and compared to empirically generated data from a model based on NIST certified values of 6deg directional/hemispherical spectral reflectance factors from 900nm to 2500nm. Employing a new NIST capability for measuring bidirectional reflectance using a cooled, extended InGaAs detector, BRF calibration measurements of the same sample were also made using NIST's STARR from 1475nm to 1625nm at an incident angle of 0deg and at viewing angles of 40deg, 45deg, and 50deg. The total combined uncertainty for BRF in this ShortWave Infrared (SWIR) range is less than 1%. This measurement capability will evolve into a BRF calibration service in SWIR region in support of NASA remote sensing missions. Keywords: BRF, BRDF, Calibration, Spectralon, Reflectance, Remote Sensing.

  2. Prefilled syringes and usability of ophthalmic viscosurgical devices

    PubMed Central

    Shiba, Takuya; Tsuneoka, Hiroshi

    2014-01-01

    Purpose To examine the influence of the configuration of prefilled syringes on the usability of ophthalmic viscosurgical devices (OVDs). Setting Department of Ophthalmology, Jikei University School of Medicine, Tokyo, Japan. Design Experimental study. Methods The maximum force needed to extrude the whole OVD (extrusion force) was compared among viscous cohesive OVDs (OPEGAN Hi® 0.85 mL and Healon® 0.85 mL) and very low viscosity dispersive OVDs (OPEGAN® 0.6 mL and OPEGAN® 1.1 mL). Additionally, to exclude the influence of any differences between syringes of viscous cohesive OVDs on the extrusion force, empty syringes of the same configuration were refilled with the same products. In addition, the syringe inner surface and that of the piston attached to the tip of the plunger were measured. Results The extrusion force of Healon 0.85 mL (3.28±0.19 kgf) was significantly (P<0.01) higher than that of OPEGAN Hi 0.85 mL (2.54±0.23 kgf). The inner syringe chamber for Healon 0.85 mL was vial shaped and had a built-in needle in the Luer tip, which was clearly different from OPEGAN Hi 0.85 mL. There were no significant differences in the extrusion force between refilled syringes. The extrusion force of OPEGAN 1.1 mL (3.44±0.12 kgf) was significantly (P<0.01) higher than that of OPEGAN 0.6 mL (1.63±0.06 kgf). The syringe of OPEGAN 1.1 mL was obviously bigger than that of OPEGAN 0.6 mL. Conclusion It was confirmed that the configuration of the syringes is another determinant of the extrusion force and a factor related to the difference in usability among products that meet the same cohesive class. PMID:25228786

  3. Development of syringe pump assisted headspace sampler.

    PubMed

    Go, Un Jeong; Eom, In-Yong

    2014-09-26

    This report describes a new platform for headspace sampling technique, i.e. a syringe pump assisted headspace sampler (SPHS). The stand type pump's syringe itself was used as a sealed sample vial and a needle trap device (NTD) was adopted as a miniaturized sorbent tube. The NTD was directly used to inject trapped VOCs into a gas chromatograph. The proposed sampler was designed to take a whole headspace volume instead of a portion of it so as to enhance easily the extraction efficiency. The performance of the SPHS-NTD system was evaluated and compared with the solid-phase microextraction (SPME) with a static headspace (HS) sampling technique. Calibration curves were obtained for aqueous TEX (toluene, ethylbenzene, and o-xylene) solutions in the concentration range of ?0.1-45 ng/mL. The calculated limit of detections (LOD, S/N=3) for TEX were 0.13 ng/mL or less. This SPHS-NTD was successfully applied to analyze aqueous TEX in river water samples and showed highly good recovery ranged from 97.2% to 105.8% for all tested VOCs. PMID:25155066

  4. 21 CFR 880.6960 - Irrigating syringe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...syringe. (a) Identification. An irrigating syringe is a device intended for medical purposes that consists of a bulb or a piston syringe with an integral or a detachable tube. The device is used to irrigate, withdraw fluid from, or instill fluid...

  5. 21 CFR 880.6960 - Irrigating syringe.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...syringe. (a) Identification. An irrigating syringe is a device intended for medical purposes that consists of a bulb or a piston syringe with an integral or a detachable tube. The device is used to irrigate, withdraw fluid from, or instill fluid...

  6. 21 CFR 880.6960 - Irrigating syringe.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...syringe. (a) Identification. An irrigating syringe is a device intended for medical purposes that consists of a bulb or a piston syringe with an integral or a detachable tube. The device is used to irrigate, withdraw fluid from, or instill fluid...

  7. 21 CFR 880.6960 - Irrigating syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...syringe. (a) Identification. An irrigating syringe is a device intended for medical purposes that consists of a bulb or a piston syringe with an integral or a detachable tube. The device is used to irrigate, withdraw fluid from, or instill fluid...

  8. Does knowledge about bloodborne pathogens influence the reuse of medical injection syringes among women in Pakistan?

    PubMed

    Janjua, Naveed Z; Mahmood, Bushra; Imran Khan, M

    2014-01-01

    Injections with re-used syringes have been identified as a major risk factor for hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in Pakistan. We analyzed data from the 2006-2007 Pakistan Demographic Health Survey (PDHS) to describe the distribution of injections administered with newly opened syringes and assessed the association of knowledge about bloodborne pathogens with syringe reuse in Pakistan. In the PDHS, women aged 12-49 years were enrolled through a multistage stratified cluster-sampling strategy across Pakistan. Approximately 10,000 women were interviewed to collect information regarding receiving injections, the use of syringes taken out of new unopened packages for their last injections, and knowledge regarding the transmission of Human Immunodeficiency Virus (HIV), HBV and HCV through the re-use of syringes and transfusion of unscreened blood. Of the 5126/10,023 women who provided information concerning their last injection, 4342 (86%) received this injection with a new syringe taken out of an unopened package. The proportion of injections received with a new syringe increased with the education level, wealth, HIV knowledge and knowledge about HCV/HBV transmission through the re-use of syringes. In the multivariable model, respondents in the 4th (adjusted odds ratio (AOR): 2.1, 95%CI: 1.4-3.0) and 5th (AOR: 2.4, 95%CI: 1.6-3.5) wealth quintiles, with some education (AOR: 1.4, 95%CI: 1.1-1.9), those in the 4th quartile of the HIV knowledge score (AOR: 1.5, 95%CI: 1.1-2.0), and those with the knowledge that a new syringe protects against HCV/HBV and HIV (AOR: 2.3, 95%CI: 1.5-3.5) were more likely to receive injections with a newly opened syringe. The patients' knowledge regarding the transmission of bloodborne pathogens is an important factor in receiving injections with a new syringe. PMID:24861642

  9. Syringe drivers: incorrect selection of syringe type from the syringe menu may result in significant errors in drug delivery.

    PubMed

    Tooke, L J; Howell, L

    2014-07-01

    There have been many reported adverse incidents due to syringe driver use, most of which have been attributable to human error. In this paper we present a previously unreported, but potentially widespread practice which may result in significant over or under-delivery of medication. Even with the naked eye it is evident that syringes of equal volume have different dimensions and to quantify this we sectioned a range of syringes and measured the inner and outer dimensions. Extensive menus for syringe brand and volumes are available on syringe drivers, offering users greater flexibility. However, this feature also allows users to select an incorrect syringe brand with potential consequences for drug delivery. We measured outputs under all selectable permutations, to determine the degree of fluid delivery variation and discovered inaccuracies in volumes ranging from 10% under-delivery to 24% over-delivery. There is a wide variation in syringe metrics and complex syringe menus may increase errors, resulting in significant under or over-delivery of medication. Availability of more than one brand of syringe in a clinical area increases the risk of adverse drug delivery events. Systems need to be implemented to minimise the risk of adverse events. PMID:24967761

  10. The cleaning of instruments and syringes

    PubMed Central

    Darmady, E. M.; Hughes, K. E. A.; Drewett, S. E.; Prince, D.; Tuke, Winifred; Verdon, Patricia

    1965-01-01

    The dangers to the handler of syringes used for routine injections were found to be negligible, but known infected syringes and those contaminated with antibiotics should be autoclaved before handling as a high proportion of these carry pathogenic organisms. Mechanical methods of cleaning syringes and instruments are assessed. The use of an artificial soil for testing purposes is described. Using this soil, ultrasonics by themselves are inadequate for cleaning syringes and instruments. Agitation with ultrasonics is essential for syringes, but is insufficient for instruments. Detergents are therefore an essential adjunct to the cleaning process. For syringes Pyroneg proved to be the most satisfactory, particularly if they had been previously siliconized. The best detergent for instruments contaminated with these types of soil was Penesolve 814 at a temperature of 95°C. but the instruments must be adequately rinsed after this treatment. A number of other detergents and cleaning agents are discussed. PMID:14247708

  11. Don't Throw Away Syringes!

    ERIC Educational Resources Information Center

    John, E.

    1975-01-01

    Describes a variety of laboratory experiments including carbon dioxide reduction, animal respiration, atmospheric pressure determination, and others, that can be performed using discarded syringes. (GS)

  12. Syringe Sharing and HIV Incidence Among Injection Drug Users and Increased Access to Sterile Syringes

    PubMed Central

    Small, Will; Buchner, Chris; Zhang, Ruth; Li, Kathy; Montaner, Julio; Wood, Evan

    2010-01-01

    Objectives. We assessed the effects of syringe exchange program (SEP) policy on rates of HIV risk behavior and HIV incidence among injection drug users. Methods. Using a multivariate generalized estimating equation and Cox regression methods, we examined syringe borrowing, syringe lending, and HIV incidence among a prospective cohort of 1228 injection drug users in Vancouver, British Columbia. Results. We observed substantial declines in rates of syringe borrowing (from 20.1% in 1998 to 9.2% in 2003) and syringe lending (from 19.1% in 1998 to 6.8% in 2003) following SEP policy change. These declines coincided with a statistically significant increase in the proportion of participants accessing sterile syringes from nontraditional SEP sources (P < .001). In multivariate analyses, the period following the change in SEP policy was independently associated with a greater than 40% reduction in syringe borrowing (adjusted odds ratio [AOR] = 0.57; 95% confidence interval [CI] = 0.49, 0.65) and lending (AOR = 0.52; 95% CI = 0.45, 0.60), as well as declining HIV incidence (adjusted hazard ratio = 0.13; 95% CI = 0.06, 0.31). Conclusions. Widespread syringe distribution appears to be a more effective SEP policy than do more restrictive SEP policies that limit syringe access. Efforts should be made to ensure that SEP policies and program design serve to maximize rather than hinder syringe access. PMID:20558797

  13. Source geometry factors for HDR (192)Ir brachytherapy secondary standard well-type ionization chamber calibrations.

    PubMed

    Shipley, D R; Sander, T; Nutbrown, R F

    2015-03-21

    Well-type ionization chambers are used for measuring the source strength of radioactive brachytherapy sources before clinical use. Initially, the well chambers are calibrated against a suitable national standard. For high dose rate (HDR) (192)Ir, this calibration is usually a two-step process. Firstly, the calibration source is traceably calibrated against an air kerma primary standard in terms of either reference air kerma rate or air kerma strength. The calibrated (192)Ir source is then used to calibrate the secondary standard well-type ionization chamber.Calibration laboratories are usually only equipped with one type of HDR (192)Ir source. If the clinical source type is different from that used for the calibration of the well chamber at the standards laboratory, a source geometry factor, ksg, is required to correct the calibration coefficient for any change of the well chamber response due to geometric differences between the sources.In this work we present source geometry factors for six different HDR (192)Ir brachytherapy sources which have been determined using Monte Carlo techniques for a specific ionization chamber, the Standard Imaging HDR 1000?Plus well chamber with a type 70010?HDR iridium source holder. The calculated correction factors were normalized to the old and new type of calibration source used at the National Physical Laboratory. With the old Nucletron microSelectron-v1 (classic) HDR (192)Ir calibration source, ksg was found to be in the range 0.983 to 0.999 and with the new Isodose Control HDR (192)Ir Flexisource ksg was found to be in the range 0.987 to 1.004 with a relative uncertainty of 0.4% (k = 2). Source geometry factors for different combinations of calibration sources, clinical sources, well chambers and associated source holders, can be calculated with the formalism discussed in this paper. PMID:25761529

  14. Source geometry factors for HDR 192Ir brachytherapy secondary standard well-type ionization chamber calibrations

    NASA Astrophysics Data System (ADS)

    Shipley, D. R.; Sander, T.; Nutbrown, R. F.

    2015-03-01

    Well-type ionization chambers are used for measuring the source strength of radioactive brachytherapy sources before clinical use. Initially, the well chambers are calibrated against a suitable national standard. For high dose rate (HDR) 192Ir, this calibration is usually a two-step process. Firstly, the calibration source is traceably calibrated against an air kerma primary standard in terms of either reference air kerma rate or air kerma strength. The calibrated 192Ir source is then used to calibrate the secondary standard well-type ionization chamber. Calibration laboratories are usually only equipped with one type of HDR 192Ir source. If the clinical source type is different from that used for the calibration of the well chamber at the standards laboratory, a source geometry factor, ksg, is required to correct the calibration coefficient for any change of the well chamber response due to geometric differences between the sources. In this work we present source geometry factors for six different HDR 192Ir brachytherapy sources which have been determined using Monte Carlo techniques for a specific ionization chamber, the Standard Imaging HDR 1000?Plus well chamber with a type 70010?HDR iridium source holder. The calculated correction factors were normalized to the old and new type of calibration source used at the National Physical Laboratory. With the old Nucletron microSelectron-v1 (classic) HDR 192Ir calibration source, ksg was found to be in the range 0.983 to 0.999 and with the new Isodose Control HDR 192Ir Flexisource ksg was found to be in the range 0.987 to 1.004 with a relative uncertainty of 0.4% (k = 2). Source geometry factors for different combinations of calibration sources, clinical sources, well chambers and associated source holders, can be calculated with the formalism discussed in this paper.

  15. Physics of Friction in Disposable Plastic Syringes

    NASA Astrophysics Data System (ADS)

    Liebmann-Vinson, A.; Vogler, E. A.; Martin, D. A.; Montgomery, D. B.; Sugg, H. W.; Monahan, L. A.

    1997-03-01

    Nosocomial applications of disposable plastic syringes demand excellent frictional behavior with no stick-slip over a broad velocity range and, simultaneously, a tight seal between stopper and barrel. However, when used in syringe pumps at slow injection speeds, stick-slip motion is frequently observed and high "break-out" forces are often necessary to initiate plunger movement after extended storage times. We have traced this frictional behavior to a velocity-dependent interaction between the elastomeric stopper and the plastic syringe barrel mediated by the syringe lubricant, almost universally a polydimethyl siloxane fluid. Lubricant properties were altered by crosslinking the surface of the silicone oil in an oxygen plasma. Changes in surface chemistry and morphology of the crosslinked oil were correlated with changes in frictional performance.

  16. A Generalized Finite Source Calibration Factor: A Natural Improvement to the Finite Source Correction Factor for Uranium Holdup Measurements

    SciTech Connect

    Gunn, C.A.; Oberer, R.B.; chiang, L.G.; Ceo, R.N.

    2003-01-28

    This paper proposes refinements to the finite source correction factor used in holdup measurements. Specifically it focuses on a more general method to estimate the average detector response for a finite source. This proposed method for the average detector response is based directly on the Generalized Geometry Holdup (GGH) assay method. First, the finite source correction factor as originally proposed is reviewed in this paper. Following this review the GGH assay method is described. Lastly, a new finite area calibration factor based on GGH is then proposed for finite point and line sources. As an alternative to the direct use of the finite arca calibration factor, finite source correction factors are also derived from this calibration factor. This new correction factor can be used in a manner similar to the finite source correction factor as currently implemented.

  17. Syringe Disposal Among Injection Drug Users in San Francisco

    PubMed Central

    Martinez, Alexis N.; Carpenter, Lisa; Geckeler, Dara; Colfax, Grant; Kral, Alex H.

    2011-01-01

    To assess the prevalence of improperly discarded syringes and to examine syringe disposal practices of injection drug users (IDUs) in San Francisco, we visually inspected 1000 random city blocks and conducted a survey of 602 IDUs. We found 20 syringes on the streets we inspected. IDUs reported disposing of 13% of syringes improperly. In multivariate analysis, obtaining syringes from syringe exchange programs was found to be protective against improper disposal, and injecting in public places was predictive of improper disposal. Few syringes posed a public health threat. PMID:20466956

  18. Syringe and Needle Size, Syringe Type, Vacuum Generation, and Needle Control in Aspiration Procedures

    SciTech Connect

    Haseler, Luke J., E-mail: l.haseler@griffith.edu.au [Griffith University, Heart Foundation Research Centre, Griffith Health Institute (Australia); Sibbitt, Randy R., E-mail: THESIBB2@aol.com [Montana Interventional and Dgnstc Radiation (United States); Sibbitt, Wilmer L., E-mail: wsibbitt@salud.unm.edu [University of New Mexico Health Sciences Center, Department of Internal Medicine (United States); Michael, Adrian A., E-mail: adrian_a_michael@yahoo.com [Texas Tech University Health Sciences Center, Department of Internal Medicine (United States); Gasparovic, Charles M., E-mail: chuck@unm.edu [University of New Mexico Health Sciences Center, MIND Institute at the University of New Mexico (United States); Bankhurst, Arthur D., E-mail: abankhurst@salud.unm.edu [University of New Mexico Health Sciences Center, Department of Internal Medicine (United States)

    2011-06-15

    Purpose: Syringes are used for diagnostic fluid aspiration and fine-needle aspiration biopsy in interventional procedures. We determined the benefits, disadvantages, and patient safety implications of syringe and needle size on vacuum generation, hand force requirements, biopsy/fluid yield, and needle control during aspiration procedures. Materials and Methods: Different sizes (1, 3, 5, 10, and 20 ml) of the conventional syringe and aspirating mechanical safety syringe, the reciprocating procedure device, were studied. Twenty operators performed aspiration procedures with the following outcomes measured: (1) vacuum (torr), (2) time to vacuum (s), (3) hand force to generate vacuum (torr-cm{sup 2}), (4) operator difficulty during aspiration, (5) biopsy yield (mg), and (6) operator control of the needle tip position (mm). Results: Vacuum increased tissue biopsy yield at all needle diameters (P < 0.002). Twenty-milliliter syringes achieved a vacuum of -517 torr but required far more strength to aspirate, and resulted in significant loss of needle control (P < 0.002). The 10-ml syringe generated only 15% less vacuum (-435 torr) than the 20-ml device and required much less hand strength. The mechanical syringe generated identical vacuum at all syringe sizes with less hand force (P < 0.002) and provided significantly enhanced needle control (P < 0.002). Conclusions: To optimize patient safety and control of the needle, and to maximize fluid and tissue yield during aspiration procedures, a two-handed technique and the smallest syringe size adequate for the procedure should be used. If precise needle control or one-handed operation is required, a mechanical safety syringe should be considered.

  19. Accelerometer calibration with nonlinear scale factor based on multi-position observation

    NASA Astrophysics Data System (ADS)

    Cai, Qingzhong; Song, Ningfang; Yang, Gongliu; Liu, Yiliang

    2013-10-01

    The calibration of an inertial measurement unit (IMU) is a key technique to improve the accuracy of an inertial navigation system. Adding more parameters into the model and reducing the estimation errors is essential for improving the calibration methods. Given its advantage of not requiring high-precision equipment, the multi-position calibration method has been widely discussed and has shown great potential in recent years. In this paper, the multi-position calibration method is improved by introducing the accelerometer nonlinear scale factor. The observation equations for the improved multi-position calibration method are established based on a nonlinear accelerometer model. The particle swarm optimization algorithm is adopted to solve the complicated nonlinear equations. In addition, Allan variance is used to determine the optimal data collection time. The accuracy and the robustness of the proposed calibration method are verified by the simulation test. The laboratory and field experiment results for a navigation-grade IMU prove that the proposed method can successfully identify the accelerometer nonlinear scale factor and improve the multi-position calibration accuracy. The comparison of several other calibration methods highlights the superior performance of the proposed method without precise orientation control.

  20. Factors affecting the repeatability of gamma camera calibration for quantitative imaging applications using a sealed source

    NASA Astrophysics Data System (ADS)

    Anizan, N.; Wang, H.; Zhou, X. C.; Wahl, R. L.; Frey, E. C.

    2015-02-01

    Several applications in nuclear medicine require absolute activity quantification of single photon emission computed tomography images. Obtaining a repeatable calibration factor that converts voxel values to activity units is essential for these applications. Because source preparation and measurement of the source activity using a radionuclide activity meter are potential sources of variability, this work investigated instrumentation and acquisition factors affecting repeatability using planar acquisition of sealed sources. The calibration factor was calculated for different acquisition and geometry conditions to evaluate the effect of the source size, lateral position of the source in the camera field-of-view (FOV), source-to-camera distance (SCD), and variability over time using sealed Ba-133 sources. A small region of interest (ROI) based on the source dimensions and collimator resolution was investigated to decrease the background effect. A statistical analysis with a mixed-effects model was used to evaluate quantitatively the effect of each variable on the global calibration factor variability. A variation of 1?cm in the measurement of the SCD from the assumed distance of 17?cm led to a variation of 1–2% in the calibration factor measurement using a small disc source (0.4?cm diameter) and less than 1% with a larger rod source (2.9?cm diameter). The lateral position of the source in the FOV and the variability over time had small impacts on calibration factor variability. The residual error component was well estimated by Poisson noise. Repeatability of better than 1% in a calibration factor measurement using a planar acquisition of a sealed source can be reasonably achieved. The best reproducibility was obtained with the largest source with a count rate much higher than the average background in the ROI, and when the SCD was positioned within 5?mm of the desired position. In this case, calibration source variability was limited by the quantum noise.

  1. Prefilled syringes: An innovation in parenteral packaging

    PubMed Central

    Makwana, Sagar; Basu, Biswajit; Makasana, Yogita; Dharamsi, Abhay

    2011-01-01

    Parenteral administration of pharmaceutical products is one of the most popular methods used to produce quick onset of action and also 100% bioavailability. Main problem occurs with the parenteral drug delivery is lack of convenience, affordability, accuracy, sterility, safety etc. Such drawbacks with this delivery system makes it less preferable. Hence, all the disadvantages of these systems can be easily overcome by use of prefilled syringes. The objective of this review article is to provide information regarding prefilled syringes; it's method of preparation, direction to use, advantages, its future scope, and development. PMID:23071944

  2. Calibration factor of track etch detectors at different temperatures of water

    E-print Network

    Yasmeen, Nuzhat

    1997-01-01

    . LR 115 Type 2 Response to Alpha Particles. . . . Calculation for the Calibration Factor . 21 . 23 . 27 . . . 30 . . . 34 III METHODS AND MATERIALS 36 Radium Standard . Radon Source Liquid Scintillation Calibration and Radon Concentration... and Jordana 1987). The average US groundwater concentration is in the range of 200- 600 pCi/L The concentration of radon in public groundwater supplies is a thousand times higher than uranium or radium, probably due to the absorption of the radium...

  3. Direct calibration in megavoltage photon beams using Monte Carlo conversion factor: validation and clinical implications.

    PubMed

    Wright, Tracy; Lye, Jessica E; Ramanathan, Ganesan; Harty, Peter D; Oliver, Chris; Webb, David V; Butler, Duncan J

    2015-01-21

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has established a method for ionisation chamber calibrations using megavoltage photon reference beams. The new method will reduce the calibration uncertainty compared to a (60)Co calibration combined with the TRS-398 energy correction factor. The calibration method employs a graphite calorimeter and a Monte Carlo (MC) conversion factor to convert the absolute dose to graphite to absorbed dose to water. EGSnrc is used to model the linac head and doses in the calorimeter and water phantom. The linac model is validated by comparing measured and modelled PDDs and profiles. The relative standard uncertainties in the calibration factors at the ARPANSA beam qualities were found to be 0.47% at 6?MV, 0.51% at 10?MV and 0.46% for the 18?MV beam. A comparison with the Bureau International des Poids et Mesures (BIPM) as part of the key comparison BIPM.RI(I)-K6 gave results of 0.9965(55), 0.9924(60) and 0.9932(59) for the 6, 10 and 18?MV beams, respectively, with all beams within 1? of the participant average. The measured kQ values for an NE2571 Farmer chamber were found to be lower than those in TRS-398 but are consistent with published measured and modelled values. Users can expect a shift in the calibration factor at user energies of an NE2571 chamber between 0.4-1.1% across the range of calibration energies compared to the current calibration method. PMID:25565406

  4. Inactive xylem can explain differences in calibration factors for thermal dissipation probe sap flow measurements.

    PubMed

    Paudel, Indira; Kanety, Tal; Cohen, Shabtai

    2013-09-01

    Thermal dissipation probes (TDPs) were calibrated in three diffuse porous fruit trees and one ornamental species in the field by comparison with heat pulse probes (nectarine and persimmon), in a greenhouse on lysimeters (apple and persimmon) and in the laboratory by pushing water through cut branches (apple, Peltophorum and nectarine). Two operational methods were used: continuous (constant thermal dissipation, CTD) and discontinuous, or transient, heating (transient thermal dissipation, TTD). Correction for the radial distribution of sap flux density was with an analytical function derived from a linear decrease in flux density with depth, as measured with a multi-depth 'Tmax' heat pulse system. When analyzed with previous calibration factors, the measured sap flow was <50% of actual value. The underestimations were consistent, and calibrations for each species in the field, greenhouse and laboratory gave approximately the same factors. Reasonable values of tree water use were obtained with the new calibration factors. Evidence is provided that even though the xylem was diffuse porous, the underestimations were caused by contact of the probes with inactive xylem along their length. The average portion of probe in contact with inactive xylem, measured in stained branches following laboratory calibrations, was 0.2-0.24. Using the measured fractions to correct temperature differentials between heated and unheated probes for CTD and TTD, based on Clearwater et al. (in Potential errors in measurement of nonuniform sap flow using heat dissipation probes. Tree Physiol 1999;19:681-687) almost completely compensated for the underestimations. Calibrations are given for each species both before and after corrections of temperature differentials, along with a multispecies calibration. These results should be an important step in reconciling many reports of different calibration factors for TDP probes. PMID:24128850

  5. Direct calibration in megavoltage photon beams using Monte Carlo conversion factor: validation and clinical implications

    NASA Astrophysics Data System (ADS)

    Wright, Tracy; Lye, Jessica E.; Ramanathan, Ganesan; Harty, Peter D.; Oliver, Chris; Webb, David V.; Butler, Duncan J.

    2015-01-01

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has established a method for ionisation chamber calibrations using megavoltage photon reference beams. The new method will reduce the calibration uncertainty compared to a 60Co calibration combined with the TRS-398 energy correction factor. The calibration method employs a graphite calorimeter and a Monte Carlo (MC) conversion factor to convert the absolute dose to graphite to absorbed dose to water. EGSnrc is used to model the linac head and doses in the calorimeter and water phantom. The linac model is validated by comparing measured and modelled PDDs and profiles. The relative standard uncertainties in the calibration factors at the ARPANSA beam qualities were found to be 0.47% at 6?MV, 0.51% at 10?MV and 0.46% for the 18?MV beam. A comparison with the Bureau International des Poids et Mesures (BIPM) as part of the key comparison BIPM.RI(I)-K6 gave results of 0.9965(55), 0.9924(60) and 0.9932(59) for the 6, 10 and 18?MV beams, respectively, with all beams within 1? of the participant average. The measured kQ values for an NE2571 Farmer chamber were found to be lower than those in TRS-398 but are consistent with published measured and modelled values. Users can expect a shift in the calibration factor at user energies of an NE2571 chamber between 0.4–1.1% across the range of calibration energies compared to the current calibration method.

  6. Combination syringe provides air-free blood samples

    NASA Technical Reports Server (NTRS)

    Pool, S. L.

    1970-01-01

    Standard syringe and spinal needle are combined in unique manner to secure air-free blood samples. Combination syringe obtains air free samples because air bubbles become insignificant when samples greater than 1 cc are drawn.

  7. The Disposable Syringe: More Experiments and Uses

    ERIC Educational Resources Information Center

    Farmer, Andrew

    1973-01-01

    Describes a variety of experiments that can be performed using the disposable syringe. Among others, these include the removal of oxygen during rusting, convection in a liquid and in air, gas collection in an electrolysis cell, small scale production of a fog, and hydrogen/oxygen extraction from a voltameter. (JR)

  8. Open-Source Syringe Pump Library

    PubMed Central

    Wijnen, Bas; Hunt, Emily J.; Anzalone, Gerald C.; Pearce, Joshua M.

    2014-01-01

    This article explores a new open-source method for developing and manufacturing high-quality scientific equipment suitable for use in virtually any laboratory. A syringe pump was designed using freely available open-source computer aided design (CAD) software and manufactured using an open-source RepRap 3-D printer and readily available parts. The design, bill of materials and assembly instructions are globally available to anyone wishing to use them. Details are provided covering the use of the CAD software and the RepRap 3-D printer. The use of an open-source Rasberry Pi computer as a wireless control device is also illustrated. Performance of the syringe pump was assessed and the methods used for assessment are detailed. The cost of the entire system, including the controller and web-based control interface, is on the order of 5% or less than one would expect to pay for a commercial syringe pump having similar performance. The design should suit the needs of a given research activity requiring a syringe pump including carefully controlled dosing of reagents, pharmaceuticals, and delivery of viscous 3-D printer media among other applications. PMID:25229451

  9. Adiabatic Compression in a Fire Syringe.

    ERIC Educational Resources Information Center

    Hayn, Carl H.; Baird, Scott C.

    1985-01-01

    Suggests using better materials in fire syringes to obtain more effective results during demonstrations which show the elevation in temperature upon a very rapid (adiabatic) compression of air. Also describes an experiment (using ignition temperatures) which introduces students to the use of thermocouples for high temperature measurements. (DH)

  10. Development of Syringe/Bottle Hybrids for Sampling Slurries

    SciTech Connect

    Coleman, C.J. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1998-01-08

    A convenient and effective sample bottle system based on simple modifications of disposable plastic syringes and bottles has been devised and tested for slurry samples. Syringe/ bottle hybrids (hereafter referred to as syringe bottles) have the convenience of regular flat-bottom bottles with screw cap closures. In addition, the syringe imparts a sliding and adjustable bottom to the bottle that forces the entire contents from the bottle. The system was designed especially to collect samples for high temperature work-ups of DWPF slurry samples. The syringe bottles together with fixed-bottom sample vial inserts would provide the DWPF with convenient and reliable methods for dealing with slurry samples.

  11. A technical study of TLD beta calibration factor for exposures to depleted uranium

    SciTech Connect

    Ashley, J.C.; Turner, J.E.; McMahan, K.L. [Oak Ridge National Lab., TN (United States); Souleyrette, M.L.; Bogard, R.S. [Oak Ridge Y-12 Plant, TN (United States)

    1995-06-01

    The beta calibration factor for converting light output (on reading a thermoluminescent dosimeter) to shallow dose equivalent has been reexamined through theoretical calculations and experimental measurements. The results support the previously determined value for contact with a depleted uranium slab but indicate that for many actual workplace situations, the contact value may be overly conservative.

  12. Access to syringes for HIV prevention for injection drug users in St. Petersburg, Russia: syringe purchase test study

    PubMed Central

    2013-01-01

    Background The HIV epidemic in Russia is concentrated among injection drug users (IDUs). This is especially true for St. Petersburg where high HIV incidence persists among the city’s estimated 80,000 IDUs. Although sterile syringes are legally available, access for IDUs may be hampered. To explore the feasibility of using pharmacies to expand syringe access and provide other prevention services to IDUs, we investigated the current access to sterile syringes at the pharmacies and the correlation between pharmacy density and HIV prevalence in St. Petersburg. Methods 965 pharmacies citywide were mapped, classified by ownership type, and the association between pharmacy density and HIV prevalence at the district level was tested. We selected two districts among the 18 districts – one central and one peripheral – that represented two major types of city districts and contacted all operating pharmacies by phone to inquire if they stocked syringes and obtained details about their stock. Qualitative interviews with 26 IDUs provided data regarding syringe access in pharmacies and were used to formulate hypotheses for the pharmacy syringe purchase test wherein research staff attempted to purchase syringes in all pharmacies in the two districts. Results No correlation was found between the density of pharmacies and HIV prevalence at the district level. Of 108 operating pharmacies, 38 (35%) did not sell syringes of the types used by IDUs; of these, half stocked but refused to sell syringes to research staff, and the other half did not stock syringes at all. Overall 70 (65%) of the pharmacies did sell syringes; of these, 49 pharmacies sold single syringes without any restrictions and 21 offered packages of ten. Conclusions Trainings for pharmacists need to be conducted to reduce negative attitudes towards IDUs and increase pharmacists’ willingness to sell syringes. At a structural level, access to safe injection supplies for IDUs could be increased by including syringes in the federal list of mandatory medical products sold by pharmacies. PMID:23452390

  13. Real-time particle monitor calibration factors and PM2.5 emission factors for multiple indoor sources.

    PubMed

    Dacunto, Philip J; Cheng, Kai-Chung; Acevedo-Bolton, Viviana; Jiang, Ruo-Ting; Klepeis, Neil E; Repace, James L; Ott, Wayne R; Hildemann, Lynn M

    2013-08-01

    Indoor sources can greatly contribute to personal exposure to particulate matter less than 2.5 ?m in diameter (PM2.5). To accurately assess PM2.5 mass emission factors and concentrations, real-time particle monitors must be calibrated for individual sources. Sixty-six experiments were conducted with a common, real-time laser photometer (TSI SidePak™ Model AM510 Personal Aerosol Monitor) and a filter-based PM2.5 gravimetric sampler to quantify the monitor calibration factors (CFs), and to estimate emission factors for common indoor sources including cigarettes, incense, cooking, candles, and fireplaces. Calibration factors for these indoor sources were all significantly less than the factory-set CF of 1.0, ranging from 0.32 (cigarette smoke) to 0.70 (hamburger). Stick incense had a CF of 0.35, while fireplace emissions ranged from 0.44-0.47. Cooking source CFs ranged from 0.41 (fried bacon) to 0.65-0.70 (fried pork chops, salmon, and hamburger). The CFs of combined sources (e.g., cooking and cigarette emissions mixed) were linear combinations of the CFs of the component sources. The highest PM2.5 emission factors per time period were from burned foods and fireplaces (15-16 mg min(-1)), and the lowest from cooking foods such as pizza and ground beef (0.1-0.2 mg min(-1)). PMID:23784066

  14. HIV Risk Behavior among Amphetamine Injectors at U.S. Syringe Exchange Programs

    ERIC Educational Resources Information Center

    Braine, Naomi; Des Jarlais, Don C.; Goldblatt, Cullen; Zadoretzky, Cathy; Turner, Charles

    2005-01-01

    The goal of this study was to compare HIV risk behaviors of amphetamine and non-amphetamine injectors at syringe exchange programs (SEP) in the United States and to identify factors associated with injection risk. This analysis is based on data from a random cross-section of participants at 13 SEPs in different parts of the country. All interviews…

  15. Comparison of injecting drug users who obtain syringes from pharmacies and syringe exchange programs in Tallinn, Estonia

    PubMed Central

    Vorobjov, Sigrid; Uusküla, Anneli; Abel-Ollo, Katri; Talu, Ave; Rüütel, Kristi; Des Jarlais, Don C

    2009-01-01

    Background Both syringe exchange programs (SEPs) and pharmacy sales of syringes are available in Estonia, though the current high incidence and high prevalence of HIV among injection drug users (IDUs) in Tallinn, Estonia requires large-scale implementation of additional harm reduction programs as a matter of great urgency. The aims of this report were to compare risk behavior and HIV infection and to assess the prevention needs among IDUs who primarily use pharmacies as their source of sterile syringes with IDUs who primarily use SEPs in Tallinn. Methods A cross-sectional study using respondent-driven sampling was used to recruit 350 IDUs for an interviewer-administered survey and HIV testing. IDUs were categorized into two groups based on their self-reported main source for syringes within the last six months. Odds ratios with 95% CI were used to compare characteristics and risk factors between the groups. Results The main sources of sterile needles for injection drug users were SEP/SEP outreach (59%) and pharmacies (41%). There were no differences in age, age at injection drug use initiation, the main drug used or experiencing overdoses. Those IDUs using pharmacies as a main source of sterile needles had lower odds for being infected with either HIV (AOR 0.54 95% CI 0.33–0.87) or HCV (AOR 0.10 95% CI 0.02–0.50), had close to twice the odds of reporting more than one sexual partner within the previous 12 months (AOR 1.88 95% CI 1.17–3.04) and engaging in casual sexual relationships (AOR 2.09 95% CI 1.24–3.53) in the last six months. Conclusion The data suggest that the pharmacy users were at a less "advanced" stage of their injection career and had lower HIV prevalence than SEP users. This suggests that pharmacies could be utilized as a site for providing additional HIV prevention messages, services for IDUs and in linking IDUs with existing harm reduction services. PMID:19232088

  16. The calibration of gas volume measuring devices at continuous and pulsatile flows.

    PubMed

    Hart, J D; Withers, R T

    1996-06-01

    A gas circuit that was capable of passing continuous or pulsatile flows via a 350 L Collins chain-compensated gasometer was built and evaluated. Various turbine volume transducers and dry gas meters were tested with gas compositions and flows that mimicked: a) inspired pulsatile flow over the physiological range and, b) mixed expirate being withdrawn from a Douglas bag. We found the Collins gasometer to be very accurate throughout its elevation, but its mixing fan is not required and atmospheric air should be left to saturate and the added water vapour calculated. Dry gas meters can be accurate to within 1% when calibrated (60 to 150 L/min), but require at least 25 L to be passed through them. The Morgan Ventilometer is an extremely reproducible device (coefficient of variation 0-0.2%, n = 60), but an increase in calibration syringe rate will elevate the calibration factor and reduce the percentage accuracy (one unit increase in calibration factor reduces accuracy by 0.6 - 1.0%). The optimal calibration syringe rate appears to be 30 - 45 b/min. Entrainment through the attached respiratory tubing can also alter the validity of the Ventilometer's calibration procedure. PMID:8836478

  17. An accurate calibration method for accelerometer nonlinear scale factor on a low-cost three-axis turntable

    NASA Astrophysics Data System (ADS)

    Pan, Jianye; Zhang, Chunxi; Cai, Qingzhong

    2014-02-01

    Strapdown inertial navigation system (SINS) requirements are very demanding on gyroscopes and accelerometers as well as on calibration. To improve the accuracy of SINS, high-accuracy calibration is needed. Adding the accelerometer nonlinear scale factor into the model and reducing estimation errors is essential for improving calibration methods. In this paper, the inertial navigation error model is simplified, including only velocity and tilt errors. Based on the simplified error model, the relationship between the navigation errors (the rates of change of velocity errors) and the inertial measurement unit (IMU) calibration parameters is presented. A tracking model is designed to estimate the rates of change of velocity errors. With a special calibration procedure consisting of six rotation sequences, the accelerometer nonlinear scale factor errors can be computed by the estimates of the rates of change of velocity errors. Simulation and laboratory test results show that the accelerometer nonlinear scale factor can be calibrated with satisfactory accuracy on a low-cost three-axis turntable in several minutes. The comparison with the traditional calibration method highlights the superior performance of the proposed calibration method without precise orientation control. In addition, the proposed calibration method saves a lot of time in comparison with the multi-position calibration method.

  18. Wrap spring clutch syringe ram and frit mixer

    SciTech Connect

    Simpson, Frank B.

    2006-07-25

    A wrap spring clutch syringe ram pushes at least one syringe with virtually instantaneous starting and stopping, and with constant motion at a defined velocity during the intervening push. The wrap spring clutch syringe ram includes an electric motor, a computer, a flywheel, a wrap spring clutch, a precision lead screw, a slide platform, and syringe reservoirs, a mixing chamber, and a reaction incubation tube. The electric motor drives a flywheel and the wrap spring clutch couples the precision lead screw to the flywheel when a computer enables a solenoid of the wrap spring clutch. The precision lead screw drives a precision slide which causes syringes to supply a portion of solution into the mixing chamber and the incubation tube. The wrap spring clutch syringe ram is designed to enable the quantitative study of solution phase chemical and biochemical reactions, particularly those reactions that occur on the subsecond time scale.

  19. Sedimentary Rock From Sand: Syringe Simulation

    NSDL National Science Digital Library

    This activity will allow students to simulate the formation of sedimentary rocks by compressing sand, water, and other materials in a syringe. The products are allowed to dry, and students will investigate how the properties of the samples of sedimentary rocks so formed are dependent on the extent of their compaction and cementation. The activity will help to explain that for most sediments to become rocks the grains need to be squeezed together (compacted) and/or glued together (cemented) and that the extent of the compaction and the strength of the cementation affect the properties of sedimentary rocks.

  20. Characterization of responses and comparison of calibration factor for commercial MOSFET detectors

    SciTech Connect

    Bharanidharan, Ganesan [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Manigandan, Durai [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Devan, Krishnamurthy [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Subramani, Vellaiyan [Department of Radiotherapy, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi (India); Gopishankar, Natanasabapathi [Department of Neurosurgery, Gamma Knife Centre, CNC All India Institute of Medical Sciences, New Delhi (India); Ganesh, Tharmar [Department of Radiotherapy, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi (India); Joshi, Rakeshchander [Department of Radiotherapy, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi (India); Rath, Gourakishore [Department of Radiotherapy, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi (India); Velmurugan, Jagadeesan [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Aruna, Prakasarao [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Ganesan, Singaravelu [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India)]. E-mail: sganesan@annauniv.edu

    2005-01-01

    A commercial metal oxide silicon field effect transistor (MOSFET) dosimeter of model TN502-RD has been characterized for its linearity, reproducibility, field size dependency, dose rate dependency, and angular dependency for Cobalt-60 ({sup 6}Co), 6-MV, and 15-MV beam energies. The performance of the MOSFET clearly shows that it is highly reproducible, independent of field size and dose rate. Furthermore, MOSFET has a very high degree of linearity, with r-value > 0.9 for all 3 energies. The calibration factor for 2 similar MOSFET detectors of model TN502-RD were also estimated and compared for all 3 energies. The calibration factor between the 2 similar MOSFET detectors shows a variation of about 1.8% for {sup 6}Co and 15 MV, and for 6 MV it shows variation of about 2.5%, indicating that calibration should be done whenever a new MOSFET is used. However, the detector shows considerable angular dependency of about 8.8% variation. This may be due to the variation in radiation sensitivity between flat and bubble sides of the MOSFET, and indicates that positional care must be taken while using MOSFET for stereotactic radiosurgery and stereotactic radiotherapy dosimetric applications.

  1. Calibrator for microflow delivery systems

    NASA Astrophysics Data System (ADS)

    Marinozzi, Franco; Bini, Fabiano; Cappa, Paolo

    2005-01-01

    An apparatus for calibrating the fluid flow rate down to 3×10-2ml/h is proposed, based on the volumetric pump working principle. Constant flow rate is assured by means of the constant speed at which the plunger of a laboratory syringe is moved. To test effectiveness of the system, a flow sensor, composed by a differential pressure transducer and a needle was calibrated and afterward utilized for characterizing a clinical drug infusion device. The proposed apparatus showed a full scale (FS) uncertainty approximately equal to 3.5% over a range of 6 ml/h. The calibration range starts at 3×10-2ml/h with a 1 ml syringe and at 3×10-3ml/h with a 0.1 ml syringe. The minimum detectable signal (evaluated at 6 dB SNR) was equal to about 1.4×10-2ml/h by using a syringe of 1 ml. The outcomes of the adopted procedure allowed a characterization of the performance of an infusion pump, without the need of the usual but somewhat cumbersome gravimetric calibration standard. Moreover, some issues about the expected resolution and uncertainty, depending on the characteristics of the system, is also reported.

  2. Needle and syringe sharing among Iranian drug injectors

    Microsoft Academic Search

    Hassan Rafiey; Hooman Narenjiha; Peymaneh Shirinbayan; Roya Noori; Morteza Javadipour; Mohsen Roshanpajouh; Mercedeh Samiei; Shervin Assari

    2009-01-01

    OBJECTIVE: The role of needle and syringe sharing behavior of injection drug users (IDUs) in spreading of blood-borne infections – specially HIV\\/AIDS – is well known. However, very little is known in this regard from Iran. The aim of our study was to determine the prevalence and associates of needle and syringe sharing among Iranian IDUs. METHODS: In a secondary

  3. Socio-Economic Status Determines Risk of Receptive Syringe Sharing Behaviors among Iranian Drug Injectors; A National Study

    PubMed Central

    Assari, Shervin; Ahmadi, Khodabakhsh; Rezazade, Majid

    2015-01-01

    Background: Although needle and syringe sharing is one of the main routs of transmission of HIV in several countries in the middle east, very little is known about how socio-economic status of injecting drug users (IDUs) is linked to the receptive syringe sharing behaviors in these countries. Aim: To study socio-economic correlates of receptive needle and syringe sharing among IDUs in Iran. Methods: The study used data from the Unhide Risk Study, a national survey of IDUs. This study sampled 636 IDUs (91% male) via snowball sampling from eight provinces in Iran in 2009. Socio-demographic and drug use characteristics were collected. We used a logistic regression to determine factors associated with receptive needle and syringe sharing during the past 6?months. Results: From 636 IDUs enrolled in this study, 68% (n?=?434) reported receptive needle and syringe sharing behaviors in the past 6?months. Odds of receptive needle and syringe sharing in the past 6?months was lower among IDUs who were male [odds ratios (OR)?=?0.29, 95% confidence interval (CI)?=?0.12–0.70], had higher education (OR?=?0.74, 95% CI?=?0.64–0.86) but higher among those who were unemployed (OR?=?4.05, 95% CI?=?1.50–10.94), and were single (OR?=?1.47, 95% CI?=?1.02–2.11). Conclusion: This study presented factors associated with risk of receptive needle and syringe sharing among Iranian IDUs. This information may be used for HIV prevention and harm reduction purposes. Socio-economic status of Iranian IDUs may be closely linked to high-risk injecting behaviors among them.

  4. Aquagenic syringeal acrokeratoderma (transient reactive papulotranslucent acrokeratoderma).

    PubMed

    Itin, P H; Lautenschlager, S

    2002-01-01

    In 1996, English and McCollough described an unusual entity in 2 sisters characterized by a transient and recurrent keratoderma exclusively on the palms after water exposure. The condition developed 3-5 min after exposure to water and resolved within a short time after drying. This finding was associated with a tightening sensation. Yan et al. coined the term 'aquagenic palmoplantar keratoderma', and the designation 'aquagenic syringeal acrokeratoderma' was suggested by MacCormack et al. Until now, a total of 8 cases have been reported. We documented 2 new cases with acquired aquagenic syringeal acrokeratoderma. A 25-year-old female had observed within the last 3 months a burning sensation on the palms after some minutes of water contact. Physical examination revealed a perfectly normal skin on the palms. Three minutes after water immersion of 20 degrees C, a whitish discoloration appeared on the palms and a thickening of the palmar skin was visible. In addition, the eccrine pores were much more prominent. Few minutes after drying the skin, the situation returned to a normal state. The second patient, a 33-year-old female noticed a painful whitish discoloration of the skin on the palms after a short period of water immersion. Sometimes the white skin could be peeled off. In the last year, hyperhidrosis developed, and a more reddish aspect of the palms appeared. In our office after rinsing the hands with water at room temperature, a whitish discoloration in the center of the palms appeared which was associated with a painful sensation. After drying, the whitish lesions disappeared almost completely within 30 min. Aquagenic palmar keratoderma describes an acquired and transient condition which occurs after brief exposure to water and disappears after drying within minutes to an hour. Only rarely may a slight hyperkeratosis remain for a longer time. The possible pathophysiology and treatment options are discussed. PMID:11834842

  5. Monte Carlo modeling provides accurate calibration factors for radionuclide activity meters.

    PubMed

    Zagni, F; Cicoria, G; Lucconi, G; Infantino, A; Lodi, F; Marengo, M

    2014-12-01

    Accurate determination of calibration factors for radionuclide activity meters is crucial for quantitative studies and in the optimization step of radiation protection, as these detectors are widespread in radiopharmacy and nuclear medicine facilities. In this work we developed the Monte Carlo model of a widely used activity meter, using the Geant4 simulation toolkit. More precisely the "PENELOPE" EM physics models were employed. The model was validated by means of several certified sources, traceable to primary activity standards, and other sources locally standardized with spectrometry measurements, plus other experimental tests. Great care was taken in order to accurately reproduce the geometrical details of the gas chamber and the activity sources, each of which is different in shape and enclosed in a unique container. Both relative calibration factors and ionization current obtained with simulations were compared against experimental measurements; further tests were carried out, such as the comparison of the relative response of the chamber for a source placed at different positions. The results showed a satisfactory level of accuracy in the energy range of interest, with the discrepancies lower than 4% for all the tested parameters. This shows that an accurate Monte Carlo modeling of this type of detector is feasible using the low-energy physics models embedded in Geant4. The obtained Monte Carlo model establishes a powerful tool for first instance determination of new calibration factors for non-standard radionuclides, for custom containers, when a reference source is not available. Moreover, the model provides an experimental setup for further research and optimization with regards to materials and geometrical details of the measuring setup, such as the ionization chamber itself or the containers configuration. PMID:25195174

  6. Infant acceptance of a bitter-tasting liquid medication: a randomized controlled trial comparing the Rx Medibottle with an oral syringe.

    PubMed

    Purswani, Murli U; Radhakrishnan, Jolly; Irfan, Khudsia R; Walter-Glickman, Cynthia; Hagmann, Stefan; Neugebauer, Richard

    2009-02-01

    The calibrated oral syringe is considered the standard system for administering liquid formulations of medications to infants. Medication acceptance using the syringe may not always be favorable, particularly with unpleasant-tasting liquids. The Rx Medibottle (The Medicine Bottle Co, Hinsdale, Illinois), an alternate drug-delivery device, is an infant-feeding bottle that contains a central sleeve within its body into which a syringe is inserted. Depressing the syringe's plunger in quick, short squirts synchronized with an infant's sucking allows drug ingestion, preventing dilution of the drug in the formula within the bottle's nipple. The Rx Medibottle costs $14.95 retail. Kraus et al demonstrated that it was more efficacious, with a higher level of infant acceptance compared with the syringe, when used to administer a 1-time dose of a pleasant-tasting liquid (acetaminophen, Tempra Syrup; Mead Johnson Nutritionals, Evansville, Indiana). Our study tests the efficacy of this bottle in administering a single dose of generic prednisolone liquid, a bitter-tasting drug, with an oral syringe serving as the control method of delivery. PMID:19188654

  7. Evaluation of factors to convert absorbed dose calibrations from graphite to water for the NPL high-energy photon calibration service

    NASA Astrophysics Data System (ADS)

    Nutbrown, R. F.; Duane, S.; Shipley, D. R.; Thomas, R. A. S.

    2002-02-01

    The National Physical Laboratory (NPL) provides a high-energy photon calibration service using 4-19 MV x-rays and 60Co ?-radiation for secondary standard dosemeters in terms of absorbed dose to water. The primary standard used for this service is a graphite calorimeter and so absorbed dose calibrations must be converted from graphite to water. The conversion factors currently in use were determined prior to the launch of this service in 1988. Since then, it has been found that the differences in inherent filtration between the NPL LINAC and typical clinical machines are large enough to affect absorbed dose calibrations and, since 1992, calibrations have been performed in heavily filtered qualities. The conversion factors for heavily filtered qualities were determined by interpolation and extrapolation of lightly filtered results as a function of tissue phantom ratio 20,10 (TPR20,10). This paper aims to evaluate these factors for all mega-voltage photon energies provided by the NPL LINAC for both lightly and heavily filtered qualities and for 60Co ?-radiation in two ways. The first method involves the use of the photon fluence-scaling theorem. This states that if two blocks of different material are irradiated by the same photon beam, and if all dimensions are scaled in the inverse ratio of the electron densities of the two media, then, assuming that all photon interactions occur by Compton scatter the photon attenuation and scatter factors at corresponding scaled points of measurement in the phantom will be identical. The second method involves making in-phantom measurements of chamber response at a constant target-chamber distance. Monte Carlo techniques are then used to determine the corresponding dose to the medium in order to determine the chamber calibration factor directly. Values of the ratio of absorbed dose calibration factors in water and in graphite determined in these two ways agree with each other to within 0.2% (1? uncertainty). The best fit to both sets of results agrees with values determined in previous work to within 0.3% (1? uncertainty). It is found that the conversion factor is not sensitive to beam filtration.

  8. Applications of spectral band adjustment factors (SBAF) for cross-calibration

    USGS Publications Warehouse

    Chander, Gyanesh

    2013-01-01

    To monitor land surface processes over a wide range of temporal and spatial scales, it is critical to have coordinated observations of the Earth's surface acquired from multiple spaceborne imaging sensors. However, an integrated global observation framework requires an understanding of how land surface processes are seen differently by various sensors. This is particularly true for sensors acquiring data in spectral bands whose relative spectral responses (RSRs) are not similar and thus may produce different results while observing the same target. The intrinsic offsets between two sensors caused by RSR mismatches can be compensated by using a spectral band adjustment factor (SBAF), which takes into account the spectral profile of the target and the RSR of the two sensors. The motivation of this work comes from the need to compensate the spectral response differences of multispectral sensors in order to provide a more accurate cross-calibration between the sensors. In this paper, radiometric cross-calibration of the Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and the Terra Moderate Resolution Imaging Spectroradiometer (MODIS) sensors was performed using near-simultaneous observations over the Libya 4 pseudoinvariant calibration site in the visible and near-infrared spectral range. The RSR differences of the analogous ETM+ and MODIS spectral bands provide the opportunity to explore, understand, quantify, and compensate for the measurement differences between these two sensors. The cross-calibration was initially performed by comparing the top-of-atmosphere (TOA) reflectances between the two sensors over their lifetimes. The average percent differences in the long-term trends ranged from $-$5% to $+$6%. The RSR compensated ETM+ TOA reflectance (ETM+$^{ast}$) measurements were then found to agree with MODIS TOA reflectance to within 5% for all bands when Earth Observing-1 Hy- erion hyperspectral data were used to produce the SBAFs. These differences were later reduced to within 1% for all bands (except band 2) by using Environmental Satellite Scanning Imaging Absorption Spectrometer for Atmospheric Cartography hyperspectral data to produce the SBAFs.

  9. Needle and syringe sharing among Iranian drug injectors

    PubMed Central

    Rafiey, Hassan; Narenjiha, Hooman; Shirinbayan, Peymaneh; Noori, Roya; Javadipour, Morteza; Roshanpajouh, Mohsen; Samiei, Mercedeh; Assari, Shervin

    2009-01-01

    Objective The role of needle and syringe sharing behavior of injection drug users (IDUs) in spreading of blood-borne infections – specially HIV/AIDS – is well known. However, very little is known in this regard from Iran. The aim of our study was to determine the prevalence and associates of needle and syringe sharing among Iranian IDUs. Methods In a secondary analysis of a sample of drug dependents who were sampled from medical centers, prisons and streets of the capitals of 29 provinces in the Iran in 2007, 2091 male IDUs entered. Socio-demographic data, drug use data and high risk behaviors entered to a logistic regression to determine independent predictors of lifetime needle and syringe sharing. Results 749(35.8%) reported lifetime experience of needle and syringe sharing. The likelihood of lifetime needle and syringe sharing was increased by female gender, being jobless, having illegal income, drug use by family members, pleasure/enjoyment as causes of first injection, first injection in roofless and roofed public places, usual injection at groin, usual injection at scrotum, lifetime experience of nonfatal overdose, and history of arrest in past year and was decreased by being alone at most injections. Conclusion However this data has been extracted from cross-sectional design and we can not conclude causation, some of the introduced variables with association with needle and syringe sharing may be used in HIV prevention programs which target reducing syringe sharing among IDUs. PMID:19643014

  10. Non-prescription Syringe Sales in California: A Qualitative Examination of Practices among 12 Local Health Jurisdictions

    PubMed Central

    Backes, Glenn; Martinez, Alexis; McFarland, Willi

    2010-01-01

    Legislation permitting non-prescription syringe sales (NPSS) was passed in 2004 in California as a structural intervention designed to expand access to syringes for injection drug users. As of December 2009, 19 of California’s 61 local health jurisdictions (LHJs) have approved policies to authorize pharmacies to sell non-prescription syringes. The legislation faces termination in 2010 if current evaluation efforts fail to demonstrate outcomes defined in the legislation. Using qualitative methods, we examined the systems and procedures associated with implementation; identified facilitators and barriers to implementation among 12 LHJs, and documented the role of public health in initiating and sustaining local programs. We identified consistent activities that led to policy implementation among LHJs and discovered several barriers that were associated with failure to implement local programs. Factors leading to NPSS were public health leadership; an inclusive planning process, marketing the program as a public health initiative; learning from others’ efforts, successes, and failures; and identifying acceptable syringe disposal options in advance of program implementation. Health departments that were confronted with political and moral arguments lost momentum and ultimately assigned a lower priority to the initiative citing the loss of powerful public health advocates or a lack of human resources. Additional barriers were law enforcement, elected officials, and pharmacy opposition, and failure to resolve syringe disposal options to the satisfaction of important stakeholders. The lessons learned in this study should provide useful guidance for the remaining LHJs in California without NPSS programs. PMID:20405227

  11. [Measuring the calibration factor of a light scattering dust monitor for CO2 arc welding fumes].

    PubMed

    Ojima, Jun

    2002-12-01

    In Japan, a light scattering type digital dust monitor is most commonly used for dust concentration measurement in a working environment. In this study, the calibration factors of a digital dust monitor (K-factor) for several welding fumes were measured in a laboratory. During the experiment, fumes were generated from CO2 arc welding performed by an automatic welding robot. The examined welding wires were JIS Z 3312, Z 3313, Z 3315, Z 3317 and Z 3320. The mass and relative concentrations of the welding fumes were measured simultaneously by a total/respirable (TR) dust sampler and a digital dust monitor at a welding current of 100 A, 150 A, 200 A, 250 A and 300 A. The particle size distributions of welding fumes were measured by a low pressure impactor at a welding current of 100 A and 300 A. A significant effect of the welding current on the K-factor was recognized for all the examined wires. In the most remarkable case, a four-fold difference in the K-factors was found when the fumes were generated from a flux cored wire for mild steel (JIS Z 3313). The particle size distributions of fumes were also affected by the welding current. The coefficients of variation in the measured K-factor were 7.8-40.5%. PMID:12506861

  12. The Association Between Law Enforcement Encounters and Syringe Sharing Among IDUs on Skid Row: A Mixed Methods Analysis

    PubMed Central

    Simon-Freeman, Rebecca; Bluthenthal, Ricky N.

    2013-01-01

    The legal environment is one factor that influences injection drug users' (IDUs) risk for HIV and other bloodborne pathogens such as hepatitis C virus (HCV). We examined the association between law enforcement encounters (i.e., arrests and citations) and receptive syringe sharing among IDUs in the context of an intensified policing effort. We conducted a mixed methods analysis of 30 qualitative and 187 quantitative interviews with IDUs accessing services at a Los Angeles, CA syringe exchange program from 2008 to 2009. Qualitative findings illustrate concerns related to visibility, drug withdrawal, and previous history of arrest/incarceration. In quantitative analysis, the number of citations received, current homelessness, and perceiving that being arrested would be a “big problem” were independently associated with recent syringe sharing. Findings illustrate some of the unintended public health consequences associated with intensified street-level policing, including risk for HIV and HCV transmission. PMID:23620243

  13. A treatment reengagement intervention for syringe exchangers.

    PubMed

    Kidorf, Michael; King, Van L; Peirce, Jessica; Kolodner, Ken; Brooner, Robert K

    2011-12-01

    Poor sustained treatment engagement limits the effectiveness of all modalities of substance abuse treatment. This study evaluated the efficacy of a novel treatment reengagement intervention for a subset of syringe-exchange program (SEP) participants (N = 113) that had enrolled in treatment as part of a 4-month clinical trial (M. Kidorf et al., 2009). Three reengagement conditions for participants leaving treatment were compared. Motivational referral condition (MRC) participants (n = 31) could attend group sessions that focused on renewing treatment interest. MRC plus incentive (MRC + I) participants (n = 49) could receive modest monetary incentives for attending these sessions and reenrolling in treatment. Standard referral condition participants (n = 33) could not attend groups or receive incentives. Across a 1-year observation window, almost all study participants (86%) were discharged from treatment. MRC + I participants attended more group sessions than MRC participants and were considerably more likely to reenroll in treatment than participants in the other study conditions. Reengagement strategies can further enhance the public health benefits of SEPs by increasing rates of treatment participation over time. PMID:21831559

  14. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  15. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  16. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  17. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  18. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...a syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  19. DoseRight Syringe Clip The Global Health Challenge

    E-print Network

    DoseRight Syringe Clip The Global Health Challenge Accurate liquid dosing is a necessity in cases in global health biotechnology The simple, elegant design of the device is what gives it the possibility

  20. Placing the Dynamics of Syringe Exchange Programs in the United States

    PubMed Central

    2007-01-01

    Drawing upon the broader health, social, and political geography literature this paper outlines a framework for considering place-based processes through which syringe exchange availability may be understood. It is argued that the geographic distribution of syringe exchange programs (SEPs) in the United States is linked to the social and political conditions of particular localities through three place characteristics: (1) structural constraints; (2) social and spatial distancing of injection drug users; and (3) localized action. Although SEPs remain a controversial issue and face ongoing obstacles from the government, law enforcement and local communities, they continue to operate through the efforts of grassroots organizations and local activists. Action on this issue occurs locally, and the characteristics of place-based factors will affect whether particular areas adopt SEPs. PMID:16797217

  1. Observational calibration of the projection factor of Cepheids. I. The type II Cepheid ? Pavonis

    NASA Astrophysics Data System (ADS)

    Breitfelder, J.; Kervella, P.; Mérand, A.; Gallenne, A.; Szabados, L.; Anderson, R. I.; Willson, M.; Le Bouquin, J.-B.

    2015-04-01

    Context. The distance of pulsating stars, in particular Cepheids, are commonly measured using the parallax of pulsation technique. The different versions of this technique combine measurements of the linear diameter variation (from spectroscopy) and the angular diameter variation (from photometry or interferometry) amplitudes, to retrieve the distance in a quasi-geometrical way. However, the linear diameter amplitude is directly proportional to the projection factor (hereafter p-factor), which is used to convert spectroscopic radial velocities (i.e., disk integrated) into pulsating (i.e., photospheric) velocities. The value of the p-factor and its possible dependence on the pulsation period are still widely debated. Aims: Our goal is to measure an observational value of the p-factor of the type-II Cepheid ? Pavonis. Methods: The parallax of the type-II Cepheid ? Pav was measured with an accuracy of 5% using HST/FGS. We used this parallax as a starting point to derive the p-factor of ? Pav, using the SPIPS technique (Spectro-Photo-Interferometry of Pulsating Stars), which is a robust version of the parallax-of-pulsation method that employs radial velocity, interferometric and photometric data. We applied this technique to a combination of new VLTI/PIONIER optical interferometric angular diameters, new CORALIE and HARPS radial velocities, as well as multi-colour photometry and radial velocities from the literature. Results: We obtain a value of p = 1.26 ± 0.07 for the p-factor of ? Pav. This result agrees with several of the recently derived Period-p-factor relationships from the literature, as well as previous observational determinations for Cepheids. Conclusions: Individual estimates of the p-factor are fundamental to calibrating the parallax of pulsation distances of Cepheids. Together with previous observational estimates, the projection factor we obtain points to a weak dependence of the p-factor on period. Based on observations realized with ESO facilities at Paranal Observatory under program IDs 091.D-0020 and 093.D-0316.Based on observations collected at ESO La Silla Observatory using the Coralie spectrograph mounted to the Swiss 1.2 m Euler telescope, under program CNTAC2014A-5.

  2. Syringe and needle exchange as HIV/AIDS prevention for injection drug users in Puerto Rico.

    PubMed

    Robles, R R; Colón, H M; Matos, T D; Finlinson, H A; Muñoz, A; Marrero, C A; García, M; Reyes, J C

    1998-09-01

    This study evaluated the effectiveness of the first needle exchange program (NEP) established in Puerto Rico. The data for this study were collected during the first months of the NEP from July 1995 to March 1996 in 13 communities of the San Juan metropolitan area. Subjects were the participants of two modalities of the NEP: a mobile team and a community-based drug treatment program. During the 3-week evaluation period, 2401 injection drug users (IDUs) were recruited, resulting in a total of 19,195 exchange contacts and 146,323 syringes exchanged. No significant change in drug injection was observed. However, the program was effective in reducing sharing of syringes and cookers. The study suggests that the NEP did help in reducing needle sharing in Puerto Rico. However, the HIV seropositivity in returned syringes suggests the need to continue aggressive prevention programs to arrest the epidemic among IDUs. However, factors related to the socio-cultural environment as well as cultural norms and traditions need to be considered when planning and expanding NEPs. PMID:10338952

  3. Pandemic influenza preparedness: the critical role of the syringe.

    PubMed

    Strauss, Kenneth; van Zundert, André; Frid, Anders; Costigliola, Vincenzo

    2006-05-29

    In the face of an almost unprecedented threat of a global pandemic of influenza it is imperative that stockpiling of appropriate drugs and devices begin now. One vital device is an appropriate syringe for delivering vaccine. With the potential for millions to be infected and the vaccine supply severely stretched it is imperative that the syringe used to vaccinate waste as little vaccine as possible and thus allow for a maximum number of persons to be vaccinated. Our study tested seven leading candidate vaccine syringes for dosing accuracy, dose-capacity per vial, medication wastage and a battery of ergonomic features. One device, the Flu+trade mark syringe, proved superior to the others in all important categories, possibly due to its low dead-space volume and its dosing accuracy. The data suggest that switching to this device from any of the others tested would provide between 2 and 19% additional vaccine doses per vial if the current 10-dose vials are used. Extrapolations from this data suggest that many thousands to millions of additional persons could be vaccinated in mass campaigns. Use of a syringe of this type, and the vaccine savings that would accrue, would likely be important in reducing morbidity and mortality in the event of a pandemic of influenza. PMID:16647790

  4. Sterilizable syringes: excessive risk or cost-effective option?

    PubMed Central

    Battersby, A.; Feilden, R.; Nelson, C.

    1999-01-01

    In recent years, many poorer countries have chosen to use disposable instead of sterilizable syringes. Unfortunately, the infrastructure and management systems that are vital if disposables are to be used safely do not exist. WHO estimates that up to 30% of injections administered are unsafe. The traditional sterilizable syringe had many disadvantages, some of which have been minimized through better design and the use of modern materials; others have been overcome because staff are able to demonstrate that they have performed safely. For example, the time-steam saturation-temperature (TST) indicator has enabled staff to demonstrate that a sterilizing cycle has been successfully completed. Health facility staff must be able to sterilize equipment, and the sterilizable syringe remains the least costly means of administering an injection. Data from countries that have acceptable systems for processing clinical waste indicate that safe and environmentally acceptable disposal, destruction and final containment cost nearly as much as the original cost of a disposable syringe. By careful supervision of staff behaviour and good management, some countries have demonstrated that they are able to administer safe injections with sterilizable syringes at a price they can afford. PMID:10593029

  5. Examination of energy spectrum acquisition method using shielded radiopharmaceutical syringes.

    PubMed

    Uto, Tomoyuki

    2009-09-20

    I previously reported on a spectrum sampling method with shielded syringes before use, although the report included only data obtained using technetium-99m. In this study, we sampled the energy spectrum in a similar manner using thallium-201, iodine-123, and gallium-67. In spectrum sampling, a radioisotopic source in a cylindrical shield is located midway between two opposed gamma-camera detectors equipped with collimators. An unshielded syringe before use emits excessive radiation and makes count rates too high to obtain accurate photopeak values. With a shielded syringe, we can sample the spectrum of radiation leaked from the needle side of the syringe and the unshielded part of its plunger side. Consequently, the detectors are exposed to lower-dose gamma rays and probably offer count rates appropriate to measure accurate photopeak values. The study results show the general validity of spectrum sampling and photopeak acquisition in our method. However, a syringe should be located accurately perpendicular to each detector; otherwise, gamma rays did not reach the detectors in some cases, resulting in measurement failures. In addition, when low-energy collimators are used for sampling from (123)I sources, photopeak values depend on penetration. More accurate measurements require the use of high-energy collimators. PMID:19828931

  6. Novel reduced pressure-balance syringe for chromatographic analysis.

    PubMed

    Windom, Bret C; Bruno, Thomas J

    2010-11-19

    When withdrawing a fluid sample (for additional chromatographic analyses) from an apparatus operated at a reduced pressure, a typical syringe proves to be ineffective (even if it is equipped with a gas tight plunger). It simply does not create enough pressure differential to remove a fluid sample from a reduced pressure environment. We encountered such a situation as part of efforts to extend the operation of the advanced distillation curve protocol to reduced pressures. The problem was solved by the development of a pressure balance syringe that allows reliable and precise sampling from an apparatus operating at sub-ambient pressures. This new device uses an external vacuum source to evacuate a syringe barrel, allowing a user to withdraw fluid samples from environments with pressures as low as 0.5kPa. To demonstrate the operation of the newly developed device, distillate analyses were performed on two fluids at low pressure: a predefined validation mixture, and a commercial soy based biodiesel fuel. The pressure balance syringe was used successfully for sampling in both cases. The use of the pressure balance syringe is not limited to reduced pressure distillations; indeed it can be used for a variety of applications in which chemical/compositional analyses are desired on a fluid contained in a reduced pressure environment. PMID:20961548

  7. A pilot study to compare the Episure Autodetect syringe with the glass syringe for identification of the epidural space in parturients.

    PubMed

    Habib, Ashraf S; George, Ronald B; Allen, Terrence K; Olufolabi, Adeyemi J

    2008-02-01

    The Episure AutoDetect syringe, a spring-loaded syringe, is a new loss-of-resistance syringe with an internal compression spring that applies constant pressure on the plunger. In this pilot study, we compared the spring-loaded syringe with the standard glass syringe for identification of the epidural space during initiation of epidural analgesia in parturients. The primary outcome was the incidence of failed epidural analgesia. Three-hundred and twenty-five women were enrolled. Eight residents performed 291 procedures (90%) and two attendings performed 34 procedures (10%). Epidural analgesia failed in five subjects in the glass syringe group and in no subject in the spring-loaded syringe group (P = 0.025). PMID:18227314

  8. Development of a syringe pump assisted dynamic headspace sampling technique for needle trap device.

    PubMed

    Eom, In-Yong; Niri, Vadoud H; Pawliszyn, Janusz

    2008-07-01

    This paper describes a new approach that combines needle trap devices (NTDs) with a dynamic headspace sampling technique (purge and trap) using a bidirectional syringe pump. The needle trap device is a 22-G stainless steel needle 3.5-in. long packed with divinylbenzene sorbent particles. The same sized needle, without packing, was used for purging purposes. We chose an aqueous mixture of benzene, toluene, ethylbenzene, and p-xylene (BTEX) and developed a sequential purge and trap (SPNT) method, in which sampling (trapping) and purging cycles were performed sequentially by the use of syringe pump with different distribution channels. In this technique, a certain volume (1 mL) of headspace was sequentially sampled using the needle trap; afterwards, the same volume of air was purged into the solution at a high flow rate. The proposed technique showed an effective extraction compared to the continuous purge and trap technique, with a minimal dilution effect. Method evaluation was also performed by obtaining the calibration graphs for aqueous BTEX solutions in the concentration range of 1-250 ng/mL. The developed technique was compared to the headspace solid-phase microextraction method for the analysis of aqueous BTEX samples. Detection limits as low as 1 ng/mL were obtained for BTEX by NTD-SPNT. PMID:18394635

  9. Various factors affecting the calibration of alpha track detectors: a Monte Carlo study

    E-print Network

    McCullough, Steven Patrick

    1995-01-01

    is termed the ATD calibration constant (tracks CM-2 per kBq hr m-'). The ATD calibration constant for LR 115 II type detectors was calculated using a Monte Carlo computer code. The alpha particle propagation was simulated using random trajectories...

  10. Needle and Syringe Cleaning Practices among Injection Drug Users.

    ERIC Educational Resources Information Center

    Fisher, Dennis G.; Harbke, Colin R.; Canty, John R.; Reynolds, Grace L.

    2002-01-01

    Evaluates the effect of needle exchange on the bleach-mediated disinfection (BMD) practices of 176 needle and syringe sharing injection drug users (IDUs). Results reveal that IDUs who traded sex for money or drugs were less likely to practice BMD, and IDUs who reported a reduced number of sex partners were more likely to practice BMD. (Contains 36…

  11. Social-structural contexts of needle and syringe sharing behaviours of HIV-positive injecting drug users in Manipur, India: a mixed methods investigation

    PubMed Central

    2011-01-01

    Background Few investigations have assessed risk behaviours and social-structural contexts of risk among injecting drug users (IDUs) in Northeast India, where injecting drug use is the major route of HIV transmission. Investigations of risk environments are needed to inform development of effective risk reduction interventions. Methods This mixed methods study of HIV-positive IDUs in Manipur included a structured survey (n = 75), two focus groups (n = 17), seven in-depth interviews, and two key informant interviews. Results One-third of survey participants reported having shared a needle/syringe in the past 30 days; among these, all the men and about one-third of the women did so with persons of unknown HIV serostatus. A variety of social-structural contextual factors influenced individual risk behaviours: barriers to carrying sterile needles/syringes due to fear of harassment by police and "anti-drug" organizations; lack of sterile needles/syringes in drug dealers' locales; limited access to pharmacy-sold needles/syringes; inadequate coverage by needle and syringe programmes (NSPs); non-availability of sterile needles/syringes in prisons; and withdrawal symptoms superseding concern for health. Some HIV-positive IDUs who shared needles/syringes reported adopting risk reduction strategies: being the 'last receiver' of needles/syringes and not a 'giver;' sharing only with other IDUs they knew to be HIV-positive; and, when a 'giver,' asking other IDUs to wash used needles/syringes with bleach before using. Conclusions Effective HIV prevention and care programmes for IDUs in Northeast India may hinge on several enabling contexts: supportive government policy on harm reduction programmes, including in prisons; an end to harassment by the police, army, and anti-drug groups, with education of these entities regarding harm reduction, creation of partnerships with the public health sector, and accountability to government policies that protect IDUs' human rights; adequate and sustained funding for NSPs to cover all IDU populations, including prisoners; and non-discriminatory access by IDUs to affordable needles/syringes in pharmacies. PMID:21569478

  12. The Role of Column Calibration Factor in the Study of Temperature Dependence of Thermal Diffusion Factor of Hydrogenic Trace Mixtures with Helium

    NASA Astrophysics Data System (ADS)

    Acharyya, S.; Saha, I. L.; Datta, A. K.; Chatterjee, A. K.

    1987-01-01

    The variation of column calibration factor Fs with respect to temperature change has been attained for a given column (C.J.G. Slieker and A. E. de Vries: J. Chim. Phys. 60 (1963) 172) to estimate the temperature dependence of thermal diffusion factor ?T of trace mixtures of hydrogenic isotopes in helium only to detect the existence of inelastic collision effect in the mixtures as predicted by T. K. Chattopadhyay and S. Acharyya (J. Phys. B 7 (1974) 2277). Attempts have also been made to interpret the ?T’s thus obtained in terms of the available elastic and inelastic collision theories of thermal diffusion to establish the importance of the column calibration factor in column measurements.

  13. Gas compression artefacts when testing peak expiratory flow meters with mechanically-driven syringes

    Microsoft Academic Search

    D. Navajas; J. Roca; R. Farré; M. Rotger; Facultat de Medicina

    Gas compression artefacts when testing peak expiratory flow meters with mechanically- driven syringes. D. Navajas, J. Roca, R. Farré, M. Rotger. ©ERS Journal Ltd 1997. ABSTRACT: Mechanically-driven syringes used to test peak expiratory flow (PEF) meters must produce the American Thoracic Society (ATS) standard waveforms with PEF accuracy of 2%. However, gas compression within the syringe could result in significant

  14. The Flawed Nature of the Calibration Factor in Breath-Alcohol Analysis

    NASA Astrophysics Data System (ADS)

    Labianca, Dominick A.

    2002-10-01

    Breath-alcohol analyzers used by law enforcement agencies to evaluate suspected driving-while-intoxicated (DWI) drivers are routinely calibrated with standard, dilute aqueous solutions of ethanol known as simulator solutions. The analyzers are deemed accurate if they generate results within an established margin of error consistent with ethanol concentrations equivalent to the actual concentrations of the simulator solutions. The fundamental flaw of this protocol is that it ignores the fact that a simulator solution is an ideal Henry’s law system, whereas a human test subject is not. Since breath-alcohol analysis is an application of Henry’s law, the level of accuracy ascribed to simulator-based calibrations cannot be applied to analyses involving humans because they are affected by physiological variables that can significantly impact the results of such analyses. This article addresses the importance of these variables, including blood:breath ratio variability, body temperature, and breathing pattern. Moreover, the article notes that, when standard ethanol-in-nitrogen compressed gas mixtures are used instead of aqueous simulator solutions to calibrate breath-alcohol analyzers, the same limitations of accuracy apply. Finally, emphasis is placed on the nature of the ideal calibration standard, namely that it should mimic the system to be analyzed, which is clearly not the case with the calibration protocol employed in breath-alcohol analysis.

  15. Investigation of factors affecting the heater wire method of calibrating fine wire thermocouples

    NASA Technical Reports Server (NTRS)

    Keshock, E. G.

    1972-01-01

    An analytical investigation was made of a transient method of calibrating fine wire thermocouples. The system consisted of a 10 mil diameter standard thermocouple (Pt, Pt-13% Rh) and an 0.8 mil diameter chromel-alumel thermocouple attached to a 20 mil diameter electrically heated platinum wire. The calibration procedure consisted of electrically heating the wire to approximately 2500 F within about a seven-second period in an environment approximating atmospheric conditions at 120,000 feet. Rapid periodic readout of the standard and fine wire thermocouple signals permitted a comparison of the two temperature indications. An analysis was performed which indicated that the temperature distortion at the heater wire produced by the thermocouple junctions appears to be of negligible magnitude. Consequently, the calibration technique appears to be basically sound, although several practical changes which appear desirable are presented and discussed. Additional investigation is warranted to evaluate radiation effects and transient response characteristics.

  16. Room scatter factor modelling and measurement error analysis of 192Ir HDR calibration by a Farmer chamber.

    PubMed

    Chang, Liyun; Ho, Sheng-Yow; Chui, Chen-Shou; Du, Yi-Chun; Chen, Tainsong

    2007-02-01

    We introduce an empirical formula to directly calculate the room scatter factor in the calibration of (192)Ir HDR using a Farmer chamber. Compared to the data of Selvam et al (2001 Phys. Med. Biol. 46 2299), our formula is accurate to within 0.3%. Our method saves time because the room scatter can be obtained in one calculation rather than being deduced through a series of setups of different source-chamber distances. It could also be cost effective because a calibration jig might be no longer necessary. We only need to position the applicator and chamber at a fixed space in air and measure its distance. We also analysed the effects of two possible errors arising from ignoring the room scatter and the measurement error of the source-chamber distance. We recommend that the source-chamber distance should be at least 10 cm. PMID:17228126

  17. A piezoelectric vibration-based syringe for reducing insertion force

    NASA Astrophysics Data System (ADS)

    Huang, Y. C.; Tsai, M. C.; Lin, C. H.

    2012-12-01

    Puncturing of the human skin with a needle is perhaps the most common invasive medical procedure. Clinical studies have revealed that tissue deformation and needle deflection are the primary problem for needle misplacement in percutaneous procedures. To avoid this, various techniques for reducing insertion forces during needle insertion have been considered. This paper presents a piezoelectric vibration-based syringe to reduce insertion force. AC power was applied to the piezoelectric elements to vibrate the needle with high frequency and thereby reduce the friction and cutting forces between the needle and tissue. Vibration mode shapes of the needle were observed by finite element analysis and verified by experimental results. Effects of reducing insertion force via the vibrating needle were also confirmed by inserting the needle into the porcine tissues. The proposed syringe, which minimizes the insertion force and overcomes limitations of needle materials, can be widely utilized in robot-assisted needle insertion systems.

  18. Embedded nanomicro syringe on chip for molecular therapy

    PubMed Central

    Jalil, Muhammad Arif; Suwanpayak, Nathaporn; Kulsirirat, Kathawut; Suttirak, Saisudawan; Ali, Jalil; Yupapin, Preecha P

    2011-01-01

    Background A novel nanomicro syringe system was proposed for drug storage and delivery using a PANDA ring resonator and atomic buffer. A PANDA ring is a modified optical add/drop filter, named after the well known Chinese bear. In principle, the molecule/drug is trapped by the force generated by different combinations of gradient fields and scattering photons within the PANDA ring. A nanomicro needle system can be formed by optical vortices in the liquid core waveguide which can be embedded on a chip, and can be used for long-term treatment. By using intense optical vortices, the required genes/molecules can be trapped and transported dynamically to the intended destinations via the nanomicro syringe, which is available for drug delivery to target tissues, in particular tumors. The advantage of the proposed system is that by confining the treatment area, the effect can be decreased. The use of different optical vortices for therapeutic efficiency is also discussed. PMID:22131837

  19. Introducing auto-disable syringes to the national immunization programme in Madagascar.

    PubMed Central

    Drain, Paul K.; Ralaivao, Josoa S.; Rakotonandrasana, Alexander; Carnell, Mary A.

    2003-01-01

    OBJECTIVE: To evaluate the safety and coverage benefits of auto-disable (AD) syringes, weighed against the financial and logis- tical costs, and to create appropriate health policies in Madagascar. METHODS: Fifteen clinics in Madagascar, trained to use AD syringes, were randomized to implement an AD syringe only, mixed (AD syringes used only on non-routine immunization days), or sterilizable syringe only (control) programme. During a five-week period, data on administered vaccinations were collected, interviews were conducted, and observations were recorded. FINDINGS: The use of AD syringes improved coverage rates by significantly increasing the percentage of vaccines administered on non-routine immunization days (AD-only 4.3%, mixed 5.7%, control 1.1% (P<0.05)). AD-only clinics eliminated sterilization sessions for vaccinations, whereas mixed clinics reduced the number of sterilization sessions by 64%. AD syringes were five times more expensive than sterilizable syringes, which increased AD-only and mixed clinics' projected annual injection costs by 365% and 22%, respectively. However, introducing AD syringes for all vaccinations would only increase the national immunization budget by 2%. CONCLUSION: The use of AD syringes improved vaccination coverage rates by providing ready-to-use sterile syringes on non-routine immunization days and decreasing the number of sterilization sessions, thereby improving injection safety. The mixed programme was the most beneficial approach to phasing in AD syringes and diminishing logistical complications, and it had minimal costs. AD syringes, although more expensive, can feasibly be introduced into a developing country's immunization programme to improve vaccination safety and coverage. PMID:14576886

  20. Nonprescription Syringe Sales: A Missed Opportunity for HIV Prevention in California

    PubMed Central

    Pollini, Robin A.; Rudolph, Abby E.; Case, Patricia

    2014-01-01

    Background California Senate Bill 41 (SB41), effective January 2012, is an HIV prevention measure designed to expand syringe access among injection drug users (IDUs) by allowing pharmacists to sell up to 30 syringes without a prescription. Objective We assessed SB41 implementation in two inland California counties where prevalence of injection drug use is among the highest in the nation. Design Syringe purchase trial. Setting Fresno and Kern counties, California. Participants All retail pharmacies (N=248). Main outcome measure Successful or unsuccessful syringe purchase attempt. Results Only 52 (21.0%) syringe purchase attempts were successful. The proportion of successful attempts did not vary by county or by data collector ethnicity. The most common reasons for unsuccessful syringe purchase attempts were prescription requirements (45.7%), the requested syringe size was not available (10.7%), and the pharmacy did not sell syringes (9.7%). In addition, some syringe purchase attempts (4.1%) were unsuccessful because the data collector was asked to purchase more syringes than allowed by law. Although 80% and 78% of Fresno and Kern residents, respectively, live within a 5-minute drive of a retail pharmacy, less than half live within a 5-minute drive of a pharmacy that sold syringes. Conclusion SB41 has not resulted in broad pharmacy-based syringe access in California's inland counties, where a disproportionate number of HIV/AIDS cases are associated with injection drug use. Additional steps by legislative bodies, regulatory agencies, and professional organizations are needed to actively engage pharmacies in expanding nonprescription syringe sales to reduce HIV transmission among IDUs. PMID:25575149

  1. A comparison of syringe disposal practices among injection drug users in a city with versus a city without needle and syringe programs

    PubMed Central

    Tookes, Hansel E.; Kral, Alex H.; Wenger, Lynn D.; Cardenas, Gabriel A.; Martinez, Alexis N.; Sherman, Recinda L.; Pereyra, Margaret; Forrest, David W.; Lalota, Marlene; Metsch, Lisa R.

    2012-01-01

    Background The United States (U.S.) approved use of federal funds for needle and syringe programs (NSPs) in December 2009. This study compares syringe disposal practices in a U.S. city with NSPs to a U.S. city without NSPs by examining the prevalence of improperly discarded syringes in public places and the self-reported syringe disposal practices of injection drug users (IDUs) in the two cities. Methods We conducted visual inspection walkthroughs in a random sample of the top-quartile of drug-affected neighborhoods in San Francisco, California (a city with NSPs) and Miami, Florida (a city without NSPs). We also conducted quantitative surveys of adult IDUs in San Francisco (N=602) and Miami (N=448). Results In the visual inspections, we found 44 syringes/1000 census blocks in San Francisco, and 371/1000 census blocks in Miami. Survey results showed that in San Francisco 13% of syringes IDUs reported using in the 30 days preceding the study interviews were disposed of improperly versus 95% of syringes by IDUs in Miami. In multivariable logistic regression analysis, IDUs in Miami had over 34 times the adjusted odds of public syringe disposal relative to IDUs in San Francisco (adjusted odds ratio=34.2, 95% CI = 21.92, 53.47). Conclusions We found eight-fold more improperly disposed syringes on walkthroughs in the city without NSPs compared to the city with NSPs, which was corroborated by survey data. NSPs may help IDUs dispose of their syringes safely in cities with large numbers of IDUs. PMID:22209091

  2. Modified Tessari Tourbillon technique for making foam sclerotherapy with silicone-free syringes.

    PubMed

    Whiteley, Mark S; Patel, Salil B

    2014-10-01

    The longevity of foam made using sodium tetradecyl sulphate and gas (air or a CO2:O2 mixture) is increased significantly if silicone-free syringes are used over the normal syringes containing silicone oil lubrication. However, the plungers in silicone-free syringes start sticking after several passages when making foam for sclerotherapy, preventing the smooth injection of the resulting foam. We describe a three syringe technique which allows foam to be made using the Tessari Tourbillon 'three-way stopcock' principle between two syringes, but with the foam ending up in a third syringe which has not undergone multiple passages of the plunger. This allows a smoother injection of the resultant foam, which is particularly useful when injecting small diameter veins under ultrasound control. PMID:25288590

  3. A sodium bicarbonate-acid powered blow-gun syringe for remote injection of wildlife.

    PubMed

    Lochmiller, R L; Grant, W E

    1983-01-01

    An automatic blow-gun syringe which uses carbon dioxide gas as the injecting force is described. Upon striking the animal, carbon dioxide gas is released by the chemical combination of sodium bicarbonate (baking soda) and acid (vinegar), within the blow-gun syringe. The syringe has been used successfully with captive collared peccaries (Dicotyles tajacu). It has the advantages of longer stability, dependable gas expansion, reduction of drug loss, and consistent drug injection. PMID:6302330

  4. The Sampling of Organic Solvent Vapors in Air by Motor-Powered Syringes

    Microsoft Academic Search

    PER ÖVRUM

    1986-01-01

    Motor-powered syringes used as personal samplers have been tested for determination of solvents in air. The plunger of the all-glass syringe (30?mL) is drawn out at constant speed during the sampling. The syringe now contains 30?mL air with a concentration of solvents corresponding to the mean concentration in the air during the sampling period. Normally 1?mL of the sample is

  5. Sampling of organic solvent vapors in air by motor-powered syringes

    Microsoft Academic Search

    Oevrum

    1986-01-01

    Motor-powered syringes used as personal samplers have been tested for determination of solvents in air. The plunger of the all-glass syringe (30 mL) is drawn out at constant speed during the sampling. The syringe now contains 30 mL air with a concentration of solvents corresponding to the mean concentration in the air during the sampling period. Normally 1 mL of

  6. Metabolism of ferulic and syringic acids by micromycetes.

    PubMed

    Seigle-Murandi, F; Steiman, R; Rahouti, M; Benoit-Guyod, J L; Eriksson, K E

    1990-07-01

    The ability of 814 strains of Micromycetes to grow on ferulic and syringic acids was investigated. After cultivation on solid media, 106 and 108 strains were selected and cultivated in liquid synthetic medium. Chromatographic analysis allowed classification of fungi into different groups according to the consumption of phenolic compounds and the appearance of new metabolites. Finally, Paecilomyces variotii and Pestalotia palmarum were chosen and cultivated in the presence of ferulic acid in two different culture media. These two Fungi Imperfecti were able to consume the phenolic compound rapidly and completely. PMID:2273981

  7. Observational calibration of the projection factor of Cepheids I. The Type II Cepheid kappa Pavonis

    E-print Network

    Breitfelder, Joanne; Mérand, Antoine; Gallenne, Alexandre; Szabados, Laszlo; Anderson, Richard; Willson, Matthew; Bouquin, Jean-Baptiste Le

    2015-01-01

    The distances of pulsating stars, in particular Cepheids, are commonly measured using the parallax of pulsation technique. The different versions of this technique combine measurements of the linear diameter variation (from spectroscopy) and the angular diameter variation (from photometry or interferometry) amplitudes, to retrieve the distance in a quasi-geometrical way. However, the linear diameter amplitude is directly proportional to the projection factor (hereafter p-factor), which is used to convert spectroscopic radial velocities (i.e., disk integrated) into pulsating (i.e., photospheric) velocities. The value of the p-factor and its possible dependence on the pulsation period are still widely debated. Our goal is to measure an observational value of the p-factor of the type-II Cepheid kappa Pavonis, whose parallax was measured with an accuracy of 5% using HST/FGS. We used this parallax as a starting point to derive the p-factor of kappa Pav, using the SPIPS technique, which is a robust version of the p...

  8. Effects of Syringe Material and Silicone Oil Lubrication on the Stability of Pharmaceutical Proteins

    PubMed Central

    Krayukhina, Elena; Tsumoto, Kouhei; Uchiyama, Susumu; Fukui, Kiichi

    2015-01-01

    Currently, polymer-based prefillable syringes are being promoted to the pharmaceutical market because they provide an increased break resistance relative to traditionally used glass syringes. Despite this significant advantage, the possibility that barrel material can affect the oligomeric state of the protein drug exists. The present study was designed to compare the effect of different syringe materials and silicone oil lubrication on the protein aggregation. The stability of a recombinant fusion protein, abatacept (Orencia), and a fully human recombinant immunoglobulin G1, adalimumab (Humira), was assessed in silicone oil-free (SOF) and silicone oil-lubricated 1-mL glass syringes and polymer-based syringes in accelerated stress study. Samples were subjected to agitation stress, and soluble aggregate levels were evaluated by size-exclusion chromatography and verified with analytical ultracentrifugation. In accordance with current regulatory expectations, the amounts of subvisible particles resulting from agitation stress were estimated using resonant mass measurement and dynamic flow-imaging analyses. The amount of aggregated protein and particle counts were similar between unlubricated polymer-based and glass syringes. The most significant protein loss was observed for lubricated glass syringes. These results suggest that newly developed SOF polymer-based syringes are capable of providing biopharmaceuticals with enhanced physical stability upon shipping and handling. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:527–535, 2015 PMID:25256796

  9. Design of a portable insulin syringe based on MSP430 MCU

    Microsoft Academic Search

    Wenrui Zhao; Qi Wang; Qingbo Zhan; Jianjun Zhuang; Xinbao Ning; Jing Yin

    2010-01-01

    The paper introduces the design of a novel insulin syringe based on MSP430 MCU. Controlled by an MSP430F4152 microprocessor, the syringe is designed to drive a stepper motor to complete each insulin injection with an exact preset dosage for diabetic patients. The product features small size, low power consumption, accuracy and easy manipulation, which is a best substitute for the

  10. Effects of syringe material and silicone oil lubrication on the stability of pharmaceutical proteins.

    PubMed

    Krayukhina, Elena; Tsumoto, Kouhei; Uchiyama, Susumu; Fukui, Kiichi

    2015-02-01

    Currently, polymer-based prefillable syringes are being promoted to the pharmaceutical market because they provide an increased break resistance relative to traditionally used glass syringes. Despite this significant advantage, the possibility that barrel material can affect the oligomeric state of the protein drug exists. The present study was designed to compare the effect of different syringe materials and silicone oil lubrication on the protein aggregation. The stability of a recombinant fusion protein, abatacept (Orencia), and a fully human recombinant immunoglobulin G1, adalimumab (Humira), was assessed in silicone oil-free (SOF) and silicone oil-lubricated 1-mL glass syringes and polymer-based syringes in accelerated stress study. Samples were subjected to agitation stress, and soluble aggregate levels were evaluated by size-exclusion chromatography and verified with analytical ultracentrifugation. In accordance with current regulatory expectations, the amounts of subvisible particles resulting from agitation stress were estimated using resonant mass measurement and dynamic flow-imaging analyses. The amount of aggregated protein and particle counts were similar between unlubricated polymer-based and glass syringes. The most significant protein loss was observed for lubricated glass syringes. These results suggest that newly developed SOF polymer-based syringes are capable of providing biopharmaceuticals with enhanced physical stability upon shipping and handling. PMID:25256796

  11. Determination of the Specific Heat Ratio of a Gas in a Plastic Syringe

    ERIC Educational Resources Information Center

    Chamberlain, Jeff

    2010-01-01

    The rapid compression or expansion of a gas in a plastic syringe is a poor approximation of an adiabatic process. Heat exchange with the walls of the syringe brings the gas to equilibrium in an amount of time that is not significantly greater than the length of the compression or expansion itself. Despite this limitation, it is still possible to…

  12. Glass delamination: a comparison of the inner surface performance of vials and pre-filled syringes.

    PubMed

    Zhao, Jianxiu; Lavalley, Virginie; Mangiagalli, Paolo; Wright, Justin M; Bankston, Theresa E

    2014-12-01

    The occurrence of glass delamination is a serious concern for parenteral drug products. Over the past several years, there has been a series of product recalls involving glass delamination in parenteral drugs stored in vials which has led to heightened industry and regulatory scrutiny. In this study, a two-pronged approach was employed to assess the inner surface durability of vials and pre-filled syringes. Non-siliconized syringes were used in order to directly compare glass to glass performance between vials and syringes. The vial and syringe performance was screened with pharmaceutically relevant formulation conditions. The influence of pH, buffer type, ionic strength, and glass type and source was evaluated. In addition, an aggressive but discriminating formulation condition (glutaric acid, pH 11) was used to ascertain the impact of syringe processing. Advanced analytical tools including inductively coupled plasma/mass spectrometry, scanning electron microscopy, atomic force microscopy, and dynamic secondary ion mass spectroscopy showed significant differences in glass performance between vials and syringes. Pre-filled syringes outperform vials for most tests and conditions. The manufacturing conditions for vials lead to glass defects, not found in pre-filled syringes, which result in a less chemically resistant surface. The screening methodology presented in this work can be applied to assess suitability of primary containers for specific drug applications. PMID:24938618

  13. The Washington Needle Depot: fitting healthcare to injection drug users rather than injection drug users to healthcare: moving from a syringe exchange to syringe distribution model.

    PubMed

    Small, Dan; Glickman, Andrea; Rigter, Galen; Walter, Thia

    2010-01-01

    Needle exchange programs chase political as well as epidemiological dragons, carrying within them both implicit moral and political goals. In the exchange model of syringe distribution, injection drug users (IDUs) must provide used needles in order to receive new needles. Distribution and retrieval are co-existent in the exchange model. Likewise, limitations on how many needles can be received at a time compel addicts to have multiple points of contact with professionals where the virtues of treatment and detox are impressed upon them. The centre of gravity for syringe distribution programs needs to shift from needle exchange to needle distribution, which provides unlimited access to syringes. This paper provides a case study of the Washington Needle Depot, a program operating under the syringe distribution model, showing that the distribution and retrieval of syringes can be separated with effective results. Further, the experience of IDUs is utilized, through paid employment, to provide a vulnerable population of people with clean syringes to prevent HIV and HCV. PMID:20047690

  14. The Washington Needle Depot: fitting healthcare to injection drug users rather than injection drug users to healthcare: moving from a syringe exchange to syringe distribution model

    PubMed Central

    2010-01-01

    Needle exchange programs chase political as well as epidemiological dragons, carrying within them both implicit moral and political goals. In the exchange model of syringe distribution, injection drug users (IDUs) must provide used needles in order to receive new needles. Distribution and retrieval are co-existent in the exchange model. Likewise, limitations on how many needles can be received at a time compel addicts to have multiple points of contact with professionals where the virtues of treatment and detox are impressed upon them. The centre of gravity for syringe distribution programs needs to shift from needle exchange to needle distribution, which provides unlimited access to syringes. This paper provides a case study of the Washington Needle Depot, a program operating under the syringe distribution model, showing that the distribution and retrieval of syringes can be separated with effective results. Further, the experience of IDUs is utilized, through paid employment, to provide a vulnerable population of people with clean syringes to prevent HIV and HCV. PMID:20047690

  15. Empirical Calibration of the P-Factor for Cepheid Radii Determined Using the IR Baade-Wesselink Method

    NASA Astrophysics Data System (ADS)

    Joner, Michael D.; Laney, C. D.

    2012-05-01

    We have used 41 galactic Cepheids for which parallax or cluster/association distances are available, and for which pulsation parallaxes can be calculated, to calibrate the p-factor to be used in K-band Baade-Wesselink radius calculations. Our sample includes the 10 Cepheids from Benedict et al. (2007), and three additional Cepheids with Hipparcos parallaxes derived from van Leeuwen et al. (2007). Turner and Burke (2002) list cluster distances for 33 Cepheids for which radii have been or (in a few cases) can be calculated. Revised cluster distances from Turner (2010), Turner and Majaess (2008, 2012), and Majaess and Turner (2011, 2012a, 2012b) have been used where possible. Radii have been calculated using the methods described in Laney and Stobie (1995) and converted to K-band absolute magnitudes using the methods described in van Leeuwen et al. (2007), Feast et al. (2008), and Laney and Joner (2009). The resulting pulsation parallaxes have been used to estimate the p-factor for each Cepheid. These new results stand in contradiction to those derived by Storm et al. (2011), but are in good agreement with theoretical predictions by Nardetto et al. (2009) and with interferometric estimates of the p-factor, as summarized in Groenewegen (2007). We acknowledge the Brigham Young University College of Physical and Mathematical Sciences for continued support of research done using the facilities and personnel at the West Mountain Observatory. This support is connected with NSF/AST grant #0618209.

  16. [Trial manufacture of a plunger shield for a disposable plastic syringe].

    PubMed

    Murakami, Shigeki; Emoto, Takashi; Mori, Hiroshige; Fujita, Katsuhisa; Kubo, Naoki

    2008-08-20

    A syringe-type radiopharmaceutical being supplied by a manufacturer has a syringe shield and a plunger shield, whereas an in-hospital labeling radiopharmaceutical is administered by a disposable plastic syringe without the plunger shield. In cooperation with Nihon Medi-Physics Co. Ltd., we have produced a new experimental plunger shield for the disposable plastic syringe. In order to evaluate this shielding effect, we compared the leaked radiation doses of our plunger shield with those of the syringe-type radiopharmaceutical (Medi shield type). Our plunger shield has a lead plate of 21 mm in diameter and 3 mm thick. This shield is equipped with the plunger-end of a disposal plastic syringe. We sealed 99mTc solution into a plastic syringe (Terumo Co.) of 5 ml with our plunger shield and Medi shield type of 2 ml. We measured leaked radiation doses around syringes using fluorescent glass dosimeters (Dose Ace). The number of measure points was 18. The measured doses were converted to 70 microm dose equivalent at 740 MBq of radioactivity. The results of our plunger shield and the Medi shield type were as follows: 4-13 microSv/h and 3-14 microSv/h at shielding areas, 3-545 microSv/h and 6-97 microSv/h at non-shielding areas, 42-116 microSv/h and 88-165 microSv/h in the vicinity of the syringe shield, and 1071 microSv/h and 1243 microSv/h at the front of the needle. For dose rates of shielding areas around the syringe, the shielding effects were approximately the same as those of the Medi shield type. In conclusion, our plunger shield may be useful for reducing finger exposure during the injection of an in-hospital labeled radiopharmaceutical. PMID:18772534

  17. A simple pore water hydrogen diffusion syringe sampler

    USGS Publications Warehouse

    Vroblesky, D.A.; Chapelle, F.H.; Bradley, P.M.

    2007-01-01

    Molecular hydrogen (H2) is an important intermediate product and electron donor in microbial metabolism. Concentrations of dissolved H 2 are often diagnostic of the predominant terminal electron-accepting processes in ground water systems or aquatic sediments. H2 concentrations are routinely measured in ground water monitoring wells but are rarely measured in saturated aquatic sediments due to a lack of simple and practical sampling methods. This report describes the design and development (including laboratory and field testing) of a simple, syringe-based H 2 sampler in (1) saturated, riparian sediments, (2) surface water bed sediments, and (3) packed intervals of a fractured bedrock borehole that are inaccessible by standard pumped methods. ?? 2007 National Ground Water Association.

  18. In-syringe magnetic stirring-assisted dispersive liquid-liquid microextraction for automation and downscaling of methylene blue active substances assay.

    PubMed

    Suárez, Ruth; Horstkotte, Burkhard; Cerdà, Victor

    2014-12-01

    A simple and rapid method for the determination of the methylene blue active substances assay based on in-syringe automation of magnetic stirring-assisted dispersive liquid-liquid microextraction was developed. The proposed method proved to be valid for the determination of anionic surfactant in waste, pond, well, tap, and drinking water samples. Sample mixing with reagents, extraction and phase separation were performed within the syringe of an automated syringe pump containing a magnetic stirring bar for homogenization and solvent dispersion. The syringe module was used upside-down to enable the use of chloroform as an extraction solvent of higher density than water. The calibration was found to be linear up to 0.3mg/L using only 200 µL of solvent and 4 mL of sample. The limits of detection (3?) and quantification (10?) were 7.0 µg/L and 22 µg/L, respectively. The relative standard deviation for 10 replicate determinations of 0.1mg/L SBDS was below 3%. Concentrations of anionic surfactants in natural water samples were in the range of 0.032-0.213 mg/L and no significant differences towards the standard method were found. Standard additions gave analyte recoveries between 95% and 106% proving the general applicability and adequateness of the system to MBSA index determination. Compared to the tedious standard method requiring up to 50 mL of chloroform, the entire procedure took only 345 s using 250-times less solvent. PMID:25159446

  19. Secondary syringe exchange as a model for HIV prevention programs in the Russian Federation.

    PubMed

    Irwin, Kevin; Karchevsky, Evgeni; Heimer, Robert; Badrieva, Larissa

    2006-01-01

    Effective prevention of syringe-borne transmission of HIV and the hepatitis viruses can be undermined if contact between injection drug users and the staff of prevention programs is impeded by police harassment, limited program resources, and the absence of an open "drug scene." All these are commonplace in the Russian Federation. In response, "Project Renewal," the harm reduction program of the AIDS Prevention and Control Center of the Tatarstan Ministry of Health in Kazan, has created a hybrid syringe exchange program that as its primary focus recruited and trained volunteers to provide secondary syringe exchange. To compensate for operational barriers, the program staff identified private venues and trained responsible individuals to work through their own and related networks of injectors to provide clean syringes, other harm reduction supplies, and educational materials, while facilitating the collection and removal of used and potentially contaminated syringes. Program staff developed a detailed set of tracking instruments to monitor, on a daily and weekly basis, the locations and types of contacts and the dissemination of trainings and materials to ensure that the secondary distribution network reaches its target audience. Data show that these secondary exchange sites have proven more productive than the primary mobile and fixed-site syringe exchanges in Kazan. Beginning in 2001, Project Renewal has trained other harm reduction programs in the Russian Federation to use this model of reaching injectors, identifying and training volunteers, and monitoring results of secondary syringe exchange. PMID:16809182

  20. Troll Oil Pipeline: Calibration of safety factors for cross-flow vibrations of spans on very uneven seabeds

    SciTech Connect

    Moerk, K. [DNVI, Oslo (Norway); Verley, R. [Statoil, Trondheim (Norway); Bruschi, R. [Snamprogetti, Fano (Italy)

    1995-12-31

    Within Fensfjorden on the Norwegian coast the proposed Troll Oil Pipeline passes through an area of deep water with an extremely rough and rocky sea bed characterized by rather high near bottom current velocities. In this area the pipeline will be ``multi-spanning``, i.e. it will have many spans closely spaced which interact statically and dynamically and may be subjected to vortex shedding induced oscillations. The present paper describes structural reliability analysis conducted to determine rational safety factors to be used in the design of the Troll Oil Pipeline free spans in the above rough sea bed area. These safety factors are related to a design equation expressing the limit for onset of cross-flow vibrations caused by current induced vortex shedding (in-line vibrations are not considered in this paper). The probabilistic modelling employed is described. The probability distributions used to describe the natural frequency and the distributions for the extreme current component normal to the pipeline are discussed. The estimation of natural frequency is based on an analytical equation accounting for initial deflection, axial force and boundary conditions. The boundary conditions for the equation are obtained through a finite element model of a continuous length of pipeline covering the area of interest. The extreme current distribution is based on measurement data accounting for the results of numerical and physical modelling of the current driving mechanism. Target safety levels and calibrated safety factors to be used in the design equation for the as-laid and operation conditions are proposed. Application and extension of the methodology and results to more general situations is discussed.

  1. SUMS calibration test report

    NASA Technical Reports Server (NTRS)

    Robertson, G.

    1982-01-01

    Calibration was performed on the shuttle upper atmosphere mass spectrometer (SUMS). The results of the calibration and the as run test procedures are presented. The output data is described, and engineering data conversion factors, tables and curves, and calibration on instrument gauges are included. Static calibration results which include: instrument sensitive versus external pressure for N2 and O2, data from each scan of calibration, data plots from N2 and O2, and sensitivity of SUMS at inlet for N2 and O2, and ratios of 14/28 for nitrogen and 16/32 for oxygen are given.

  2. Direct observation of syringeal muscle function in songbirds and a parrot.

    PubMed

    Larsen, Ole Naesbye; Goller, Franz

    2002-01-01

    The role of syringeal muscles in controlling the aperture of the avian vocal organ, the syrinx, was evaluated directly for the first time by observing and filming through an endoscope while electrically stimulating different muscle groups of anaesthetised birds. In songbirds (brown thrashers, Toxostoma rufum, and cardinals, Cardinalis cardinalis), direct observations of the biomechanical effects of contraction largely confirm the functions of the intrinsic syringeal muscles proposed from indirect studies. Contraction of the dorsal muscles, m. syringealis dorsalis (dS) and m. tracheobronchialis dorsalis, constricts the syringeal lumen and thus reduces airflow by adducting connective tissue masses, the medial (ML) and lateral (LL) labia. Activity of the medial portion of the dS appears to affect the position of the ML and, consequently, plays a previously undescribed role in aperture control. Under the experimental conditions used in this study, full constriction of the syringeal lumen could not be achieved by stimulating adductor muscles. Full closure may require simultaneous activation of extrinsic syringeal muscles or the supine positioning of the bird may have exerted excessive tension on the syrinx. Contraction of m. tracheobronchialis ventralis enlarges the syringeal lumen and thus increases airflow by abducting the LL but does not affect the ML. The largest syringeal muscle, m. syringealis ventralis, plays a minor role, if any, in direct aperture control and thus in gating airflow. In parrots (cockatiels, Nymphicus hollandicus), direct observations show that even during quiet respiration the lateral tympaniform membranes (LTMs) are partially adducted into the tracheal lumen to form a narrow slot. Contraction of the superficial intrinsic muscle, m. syringealis superficialis, adducts the LTMs further into the tracheal lumen but does not close the syringeal aperture fully. The intrinsic deep muscle, m. syringealis profundus, abducts the LTMs through cranio-lateral movement of a paired, protruding half-ring. The weakly developed extrinsic m. sternotrachealis seems to increase tension in the ipsilateral LTM but does not move it in or out of the syringeal lumen. PMID:11818409

  3. Comparative study of sealing capabilities and adhesiveness of injectable root canal sealers using pressure syringe technique.

    PubMed

    Dabas, U; Dabas, V K

    2001-01-01

    The accuracy with which root canal space is sealed is a major determinant in the Endodontic success. Use of pressure-syringe to introduce root canal sealer in the root canal without gutta percha or silver cone represents a modification to current technique of obturation. This study investigates the sealing capabilities and adhesiveness of various root canal sealers with the use of pressure syringe technique. Apart from eliminating the use of solid core, pressure syringe technique can be used as a new obturation method since it showed better marginal sealability than the conventional technique. PMID:11808066

  4. Optimization of labor allocation at a syringe production facility : work study

    E-print Network

    Ng, Gar Yan

    2008-01-01

    At MD Company (Singapore), the syringe value stream faces escalating labor cost and high labor turnover. Two labor allocations were proposed previously to optimize current labor resources, with the aim of controlling the ...

  5. The analysis and design of a pressure-measuring syringe utilizing elastomeric bellows

    E-print Network

    Duffley, Samuel C

    2009-01-01

    Endotracheal tube insertion requires the measurement of very low pressure. Currently, there exists no reliable method or device that is integral with the inflation syringe for measuring this pressure. Thus, a device for ...

  6. Plastic-Syringe Induced Silicone Contamination in Organic Photvoltaic Fabrication: Implications for Small-Volume Additives

    SciTech Connect

    Carr, John A.; Nalwa, Kanwar S.; Mahadevapuram, Rakesh; Chen, Yuqing; Anderegg, James; Chaudhary, Sumit

    2012-05-15

    Herein, the implications of silicone contamination found in solution-processed conjugated polymer solar cells are explored. Similar to a previous work based on molecular cells, we find this contamination as a result of the use of plastic syringes during fabrication. However, in contrast to the molecular case, we find that glass-syringe fabricated devices give superior performance than plastic-syringe fabricated devices in poly(3-hexylthiophene)-based cells. We find that the unintentional silicone addition alters the solution’s wettability, which translates to a thinner, less absorbent film on spinning. With many groups studying the effects of small-volume additives, this work should be closely considered as many of these additives may also directly alter the solutions’ wettability, or the amount of silicone dissolved off the plastic syringes, or both. Thereby, film thickness, which generally is not reported in detail, can vary significantly from device to device.

  7. Community coverage and HIV prevention: Assessing metrics for estimating HIV incidence through syringe exchange

    Microsoft Academic Search

    Robert Heimer

    2008-01-01

    BackgroundEvaluations of syringe-exchange programme effectiveness that attempt to measure “coverage” by determining the percentage of the at-risk population reached by a programme are insufficient since programmes must provide syringes on a continual basis. Determining the relationship between the extent of programme coverage and its impact (i.e., reductions in disease risk or incidence) is complicated by the lack of controlled trials

  8. KEY COMPARISON: Final Report of the comparison CCEM.RF-K8.CL: Calibration factor of thermistor mounts

    NASA Astrophysics Data System (ADS)

    de Vreede, Jan P. M.

    2005-01-01

    From February 1998 to July 1999 the measurements for a Euromet project 393 were carried out. After the decision of the GT-RF (and CCEM) to extend this project into a worldwide key comparison (CCEM.RF-K8.CL with GT-RF 98-1 as its non-European part) measurements were carried out between August 1999 and December 2000. Two travelling standards were measured by 17 national standard institutes. The results at all selected frequencies in the range from 10 MHz to 18 GHz show a good agreement between most of the participants. The maximum stated uncertainty for the calibration factor ranges from 0.3% at 50 MHz to more than 4.0% at 18 GHz, independent of the type of connector on the DUT. Almost all results are consistent within the claimed uncertainty. The uncertainty stated for the reflection coefficient was up to 0.03 in almost all cases. Most of the results are consistent within the claimed uncertainty. The evaluation of the Euromet project led to a new comparison (project 633) to study potential problems at several laboratories. One non-European laboratory was invited to participate as well in this project (KCDB code EUROMET.EM.RF-K8.CL). Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the Mutual Recognition Arrangement (MRA).

  9. SCORE Study Report 7: Incidence of Intravitreal Silicone Oil Droplets Associated With Staked-on Versus Luer Cone Syringe Design

    PubMed Central

    Scott, Ingrid U.; Oden, Neal L.; VanVeldhuisen, Paul C.; Ip, Michael S.; Blodi, Barbara A.; Antoszyk, Andrew N.

    2009-01-01

    PURPOSE To evaluate the incidence of intravitreal silicone oil (SO) droplets associated with intravitreal injections using a staked-on versus luer cone syringe design in the Standard Care versus COrticosteroid in REtinal Vein Occlusion (SCORE) Study. DESIGN Prospective, randomized, phase III clinical trial. METHODS The incidence of intravitreal SO was compared among participants exposed to the staked-on syringe design, the luer cone syringe design, or both of the syringe designs in the SCORE Study, which evaluated intravitreal triamcinolone acetonide injection(s) for vision loss secondary to macular edema associated with central or branch retinal vein occlusion. Injections were given at baseline and 4-month intervals, based on treatment assignment and study-defined re-treatment criteria. Because intravitreal SO was observed following injections in some participants, investigators were instructed, on September 22, 2006, to look for intravitreal SO at all study visits. On November 1, 2007, the luer cone syringe design replaced the staked-on syringe design. RESULTS 464 participants received a total of 1205 injections between November 4, 2004 and February 28, 2009. Intravitreal SO was noted in 141/319 (44%) participants exposed only to staked-on syringes, 11/87 (13%) exposed to both syringe designs, and 0/58 exposed only to luer cone syringes (p<0.0001). Among participants with first injections after September 22, 2006, intravitreal SO was noted in 65/114 (57%) injected only with staked-on syringes compared with 0/58 injected only with luer cone syringes. Differential follow-up is unlikely to explain these results. CONCLUSION In the SCORE Study, luer cone syringe design is associated with a lower frequency of intravitreal SO droplet occurrence compared with the staked-on syringe design, likely due to increased residual space in the needle hub with the luer cone design. PMID:19674727

  10. 60 FR 40182 - Drug Export; NeupogenRegister Recombinant Methionyl Granulocyte Colony Stimulating Factor (r...

    Federal Register 2010, 2011, 2012, 2013, 2014

    1995-08-07

    ...Stimulating Factor (r-metHuG-CSF) With Sorbitol AGENCY: Food and Drug Administration...Stimulating Factor (r-metHuG-CSF) with sorbitol in vials, pre-filled syringes, and...Stimulating Factor (r-metHuG- CSF) with sorbitol in vials, pre-filled syringes,...

  11. Syringe Access, Syringe Sharing, and Police Encounters among People Who Inject Drugs in New York City: A Community-Level Perspective

    PubMed Central

    Beletsky, Leo; Heller, Daliah; Jenness, Samuel M.; Neaigus, Alan; Gelpi-Acosta, Camila; Hagan, Holly

    2013-01-01

    Background Injection drug user (IDU) experience and perceptions of police practices may alter syringe exchange program (SEP) use or influence risky behaviour. Previously, no community-level data had been collected to identify the prevalence or correlates of police encounters reported by IDUs in the United States. Methods New York City IDUs recruited through respondent-driven sampling were asked about past-year police encounters and risk behaviours, as part of the National HIV Behavioural Surveillance study. Data were analysed using multiple logistic regression. Results A majority (52%) of respondents (n=514) reported being stopped by police officers; 10% reported syringe confiscation. In multivariate modelling, IDUs reporting police stops were less likely to use SEPs consistently (adjusted odds ratio [AOR]=0.59; 95% confidence interval [CI]=0.40–0.89), and IDUs who had syringes confiscated may have been more likely to share syringes (AOR=1.76; 95% CI=0.90–3.44), though the finding did not reach statistical significance. Conclusions Findings suggest that police encounters may influence consistent SEP use. The frequency of IDU-police encounters highlights the importance of including contextual and structural measures in infectious disease risk surveillance, and the need to develop approaches harmonizing structural policing and public health. PMID:23916801

  12. The Washington Needle Depot: fitting healthcare to injection drug users rather than injection drug users to healthcare: moving from a syringe exchange to syringe distribution model

    Microsoft Academic Search

    Dan Small; Andrea Glickman; Galen Rigter; Thia Walter

    2010-01-01

    Needle exchange programs chase political as well as epidemiological dragons, carrying within them both implicit moral and political goals. In the exchange model of syringe distribution, injection drug users (IDUs) must provide used needles in order to receive new needles. Distribution and retrieval are co-existent in the exchange model. Likewise, limitations on how many needles can be received at a

  13. Chemicals eluting from disposable plastic syringes and syringe filters alter neurite growth, axogenesis and the microtubule cytoskeleton in cultured hippocampal neurons.

    PubMed

    Lee, Tet Woo; Tumanov, Sergey; Villas-Bôas, Silas G; Montgomery, Johanna M; Birch, Nigel P

    2015-04-01

    Cultures of dissociated hippocampal neurons are often used to study neuronal cell biology. We report that the development of these neurons is strongly affected by chemicals leaching from commonly used disposable medical-grade syringes and syringe filters. Contamination of culture medium by bioactive substance(s) from syringes and filters occurred with multiple manufacturing lots and filter types under normal use conditions and resulted in changes to neurite growth, axon formation and the neuronal microtubule cytoskeleton. The effects on neuronal morphology were concentration-dependent and significant effects were detected even after substantial dilution of the contaminated medium. Gas chromatography-mass spectrometry analyses revealed many chemicals eluting from the syringes and filters. Three of these chemicals (stearic acid, palmitic acid and 1,2-ethanediol monoacetate) were tested but showed no effects on neurite growth. Similar changes in neuronal morphology were seen with high concentrations of bisphenol A and dibutyl phthalate, two hormonally active plasticisers. Although no such compounds were detected by gas chromatography-mass spectrometry, unknown plasticisers in leachates may affect neurites. This is the first study to show that leachates from laboratory consumables can alter the growth of cultured hippocampal neurons. We highlight important considerations to ensure leachate contamination does not compromise cell biology experiments. Cultures of dissociated hippocampal neurons are used to study many aspects of neuronal cell biology. We report that leachates from medical grade syringes and sterile syringe filters may alter neurite growth in these cultures. These consumables are commonly used in the laboratory. Our results serve as a reminder to other researchers to ensure that leachate contamination does not compromise experimental results, and that specifying details about which materials were used is crucial. The merged image shows the differences between dissociated hippocampal neurons that were cultured for 2 days in control medium (left half of image) compared to those cultured in syringe-filtered medium (right half of image), which have a greater number of long thin neurites. Neurons were immunolabelled for Tau (green) and MAP2 (red) and nuclei labelled with DAPI (blue). PMID:25522164

  14. A Novel Tetrahydrofolate-Dependent O-Demethylase Gene Is Essential for Growth of Sphingomonas paucimobilis SYK-6 with Syringate

    Microsoft Academic Search

    Eiji Masai; Miyuki Sasaki; Yasunori Minakawa; Tomokuni Abe; Tomonori Sonoki; Keisuke Miyauchi; Yoshihiro Katayama; Masao Fukuda

    2004-01-01

    Sphingomonas paucimobilis SYK-6 degrades syringate to 3-O-methylgallate (3MGA), which is finally con- verted to pyruvate and oxaloacetate via multiple pathways in which protocatechuate 4,5-dioxygenase, 3MGA dioxygenase, and gallate dioxygenase are involved. Here we isolated the syringate O-demethylase gene (desA), which complemented the growth deficiency on syringate of a Tn5 mutant of the SYK-6 derivative strain. The desA gene is located

  15. Non-prescription Syringe Sales in California: A Qualitative Examination of Practices among 12 Local Health Jurisdictions

    Microsoft Academic Search

    Valerie J. Rose; Glenn Backes; Alexis Martinez; Willi McFarland

    2010-01-01

    Legislation permitting non-prescription syringe sales (NPSS) was passed in 2004 in California as a structural intervention\\u000a designed to expand access to syringes for injection drug users. As of December 2009, 19 of California’s 61 local health jurisdictions\\u000a (LHJs) have approved policies to authorize pharmacies to sell non-prescription syringes. The legislation faces termination\\u000a in 2010 if current evaluation efforts fail to

  16. Dispersive liquid-liquid microextraction combined with semi-automated in-syringe back extraction as a new approach for the sample preparation of ionizable organic compounds prior to liquid chromatography.

    PubMed

    Melwanki, Mahaveer B; Fuh, Ming-Ren

    2008-07-11

    Dispersive liquid-liquid microextraction (DLLME) followed by a newly designed semi-automated in-syringe back extraction technique has been developed as an extraction methodology for the extraction of polar organic compounds prior to liquid chromatography (LC) measurement. The method is based on the formation of tiny droplets of the extractant in the sample solution using water-immiscible organic solvent (extractant) dissolved in a water-miscible organic dispersive solvent. Extraction of the analytes from aqueous sample into the dispersed organic droplets took place. The extracting organic phase was separated by centrifuging and the sedimented phase was withdrawn into a syringe. Then in-syringe back extraction was utilized to extract the analytes into an aqueous solution prior to LC analysis. Clenbuterol (CB), a basic organic compound used as a model, was extracted from a basified aqueous sample using 25 microL tetrachloroethylene (TCE, extraction solvent) dissolved in 500 microL acetone (as a dispersive solvent). After separation of the organic extracting phase by centrifuging, CB enriched in TCE phase was back extracted into 10 microL of 1% aqueous formic acid (FA) within the syringe. Back extraction was facilitated by repeatedly moving the plunger back and forth within the barrel of syringe, assisted by a syringe pump. Due to the plunger movement, a thin organic film is formed on the inner layer of the syringe that comes in contact with the acidic aqueous phase. Here, CB, a basic analyte, will be protonated and back extracted into FA. Various parameters affecting the extraction efficiency, viz., choice of extraction and dispersive solvent, salt effect, speed of syringe pump, back extraction time period, effect of concentration of base and acid, were evaluated. Under optimum conditions, precision, linearity (correlation coefficient, r(2)=0.9966 over the concentration range of 10-1000 ng mL(-1) CB), detection limit (4.9 ng mL(-1)), enrichment factor (175), relative recovery (97%) had been obtained. The applicability of this newly developed method was investigated for the analysis of CB in the water samples from river, lake and stream water. PMID:18513730

  17. The TRPA1 Agonist, Methyl Syringate Suppresses Food Intake and Gastric Emptying

    PubMed Central

    Song, Seo Hyeon; Jung, Myungji; Kim, Yiseul; Rhyu, Mee-Ra

    2013-01-01

    Transient receptor potential channel ankryn 1 (TRPA1) expressed in the gastrointestinal tract is associated with gastric motility, gastric emptying, and food intake. In this study, we investigated the effects of methyl syringate, a specific and selective TRPA1 agonist, on food intake, gastric emptying, and gut hormone levels in imprinting control region (ICR) mice. The administration of methyl syringate suppressed cumulative food intake and gastric emptying. In addition, treatment with ruthenium red (RR), a general cation channel blocker, and HC-030031, a selective TRPA1 antagonist, inhibited methyl syringate-induced reduction of food intake and delayed gastric emptying in ICR mice. Methyl syringate also increased plasma peptide YY (PYY) levels, but not glucagon-like peptide-1 (GLP-1) levels. The elevation in PYY was blocked by treatment with RR and HC-030031. The present findings indicate that methyl syringate regulates food intake and gastric emptying through a TRPA1-mediated pathway and, by extension, can contribute to weight suppression. PMID:23990963

  18. Intravenous infusions in hyperbaric chambers: effect of compression on syringe function.

    PubMed

    Hopson, A S M; Greenstein, A

    2007-06-01

    Haemodynamic instability is a recognised phenomenon in critically ill patients undergoing hyperbaric therapy. Instability may result from the effects of ambient pressure on the cardiovascular system, devices involved in infusion of drugs and fluids, or a combination of the two. The effect of hyperbaric pressure on air-containing spaces in syringes has not been previously measured. We connected 60-ml syringes (Terumo Corporation, Tokyo, Japan) containing coloured water to low volume extensions via three-way taps. We examined the effect of pressurisation to 2.4 and 2.8 atmospheres absolute (ATA) on the syringes by measuring the displacement of the coloured water in the low volume extension set. There was compression of air spaces within the syringe causing retrograde flow of fluid within the low volume extension set. The mean (95% CI) change in volume was 154 (141-168) microl at 2.4 ATA, and 197 (183-212) microl at 2.8 ATA (both p < 0.0001). We conclude that hyperbaric exposure may cause clinically significant changes in syringe function at infusion rates < 100 ml. h(-1). PMID:17506740

  19. Calibrating Dark Energy

    E-print Network

    Roland de Putter; Eric V. Linder

    2008-08-01

    Exploring the diversity of dark energy dynamics, we discover a calibration relation, a uniform stretching of the amplitude of the equation of state time variation with scale factor. This defines homogeneous families of dark energy physics. The calibration factor has a close relation to the standard time variation parameter w_a, and we show that the new, calibrated w_a describes observables, i.e. distance and Hubble parameter as a function of redshift, typically to an accuracy level of 10^{-3}. We discuss implications for figures of merit for dark energy science programs.

  20. Effect of the Siliconization Method on Particle Generation in a Monoclonal Antibody Formulation in Pre-filled Syringes.

    PubMed

    Gerhardt, Alana; Nguyen, Bao H; Lewus, Rachael; Carpenter, John F; Randolph, Theodore W

    2015-05-01

    Silicone oil is used as a lubricant in glass pre-filled syringes (PFS) but can contribute to the generation of particles within protein formulations in PFS. To mitigate the production of such particles, various silicone oil coating processes have been proposed. In this study, three siliconization methods (the "covalent" method, the "baked silicone oil" method, and the "liquid silicone oil" method) were used to coat glass syringes with silicone oil. Glide forces were determined for syringes coated by each method. Then, a monoclonal antibody formulation or a buffer solution were incubated in the coated syringes in either the presence or absence of an air bubble, and the syringes were rotated end-over-end to induce air bubble movement within the syringe. The particle concentrations were measured throughout the incubation period using flow microscopy. The coating method did not affect particle concentrations measured in buffer alone, nor did the coating method affect particle concentrations measured in antibody formulations in the absence of an air bubble. Particle concentrations were influenced by the syringe coating method in protein formulations agitated in the presence of an air bubble, with the most particles formed in syringes lubricated with liquid silicone oil. Fewer particles were produced in syringes lubricated with baked silicone oil, and the fewest particles were produced in syringes with covalently-attached silicone oil. However, the glide forces measured in syringes coated with silicone oil by each method are inversely correlated with the measured particle concentrations. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:1601-1609, 2015. PMID:25740412

  1. Negotiating access: Social barriers to purchasing syringes at pharmacies in Tijuana, Mexico

    PubMed Central

    Davidson, Peter J.; Lozada, Remedios; Rosen, Perth C.; Macias, Armando; Gallardo, Manuel; Pollini, Robin A.

    2012-01-01

    Background One common public health response to the emergence of HIV has been the provision of sterile syringes to people who inject drugs. In Mexico specialized syringe exchanges are rare, and the sale of needles through pharmacies is often the only way people who inject drugs can obtain sterile syringes. However, people who inject drugs in Tijuana, Mexico report considerable social barriers to successfully purchasing syringes at pharmacies. Methods Between October 2008 and March 2009 we conducted seven in-depth focus groups with 47 people who inject drugs in Tijuana, Mexico. Focus group transcripts were analysed using a descriptive and thematic approach rooted in grounded theory. Results We found that injectors offered a number of explanations for why pharmacies were reluctant to sell them syringes, including fear of police; attitudes toward drug use; fear of stereotypical drug user behaviour such as petty theft, violence, or distressing behaviour; and related fears that an obvious drug using clientèle would drive away other customers. Injectors described a range of ways of attempting to re-frame or negotiate interactions with pharmacy staff so that these and related concerns were ameliorated. These included tactics as simple as borrowing cleaner clothing, through to strategies for becoming ‘known’ to pharmacy staff as an individual rather than as a member of a stigmatized group. Conclusion Increasing the ability of pharmacy staff and people who inject drugs to successfully negotiate syringe sales are highly desirable. Interventions designed to improve this likelihood need to capitalize on existing solutions developed ad-hoc by people who inject drugs and pharmacy staff, and should focus on broadening the range of ‘identities’ which pharmacy staff are able to accept as legitimate customers. Approaches to achieve this end might include sensitizing pharmacy staff to the needs of people who inject drugs; facilitating individual drug users meeting individual pharmacy staff; and working with drug users to reduce behaviours seen as problematic by pharmacy staff. PMID:22676968

  2. [Development of an auto-retractable self-disable safety syringe with high stability].

    PubMed

    Zhang, Yonghua; He, Jianhui; Chen, Ou; Li, Huihui; Li, Xianyu

    2010-05-01

    An auto-retractable self-disable safety syringe is introduced. The product mainly consists of barrel, plunger hander, needle holder, spring and needle cap. After injection, the clasp on top of plunger hander will be jammed with the outshoot of needle holder, meanwhile, the plunger hander tip expands the stop structure and consequently the compression spring pulls the needle and needle holder back into plunger hander. The technical parameters of present syringe such as break force, needle holder push out force and plunger hander lock force are very stable while working. With simple structure, reasonable design, easy manufacture and assemble, this product can been widely used in relevant area. PMID:20812647

  3. In-syringe-stirring: a novel approach for magnetic stirring-assisted dispersive liquid-liquid microextraction.

    PubMed

    Horstkotte, Burkhard; Suárez, Ruth; Solich, Petr; Cerdà, Víctor

    2013-07-25

    For the first time, the use of a magnetic stirrer within the syringe of an automated syringe pump and the resulting possible analytical applications are described. A simple instrumentation following roughly the one from sequential injection analyzer systems is used in combination with an adaptor, which is placed onto the barrel of a glass syringe. Swirling around the longitudinal axis of the syringe and holding two strong neodymium magnets, it causes a rotating magnetic field and serves as driver for a magnetic stirring bar placed inside of the syringe. In a first study it was shown that this approach leads to a sealed but also automatically adaptable reaction vessel, the syringe, in which rapid and homogeneous mixing of sample with the required reagents within short time can be carried out. In a second study in-a-syringe magnetic stirring-assisted dispersive liquid-liquid microextraction (MSA-DLLME) was demonstrated by the application of the analyzer system to fluorimetric determination of aluminum in seawater samples using lumogallion. A linear working range up to 1.1 ?mol L(-1) and a limit of detection of 6.1 nmol L(-1) were found. An average recovery of 106.0% was achieved for coastal seawaters with a reproducibility of 4.4%. The procedure lasted 210 s including syringe cleaning and only 150 ?L of hexanol and 4.1 mL of sample were required. PMID:23845481

  4. Community Impact of Pharmacy-Randomized Intervention to Improve Access to Syringes and Services for Injection Drug Users

    ERIC Educational Resources Information Center

    Crawford, Natalie D.; Amesty, Silvia; Rivera, Alexis V.; Harripersaud, Katherine; Turner, Alezandria; Fuller, Crystal M.

    2014-01-01

    Objectives: In an effort to reduce HIV transmission among injection drug users (IDUs), New York State deregulated pharmacy syringe sales in 2001 through the Expanded Syringe Access Program by removing the requirement of a prescription. With evidence suggesting pharmacists' ability to expand their public health role, a structural,…

  5. Investigation by syringe method of effect of tampons on production in vitro of toxic shock syndrome toxin 1 by Staphylococcus aureus.

    PubMed Central

    Lee, A C; Crass, B A; Bergdoll, M S

    1987-01-01

    A syringe method was designed to test the effect of tampons on the growth of three toxic shock syndrome-associated strains of Staphylococcus aureus and their in vitro production of toxic shock syndrome toxin 1 (TSST-1) under different conditions. Various amounts of TSST-1 were recovered from different tampons inoculated with these strains. Generally, the addition of 10% porcine blood to the growth medium, incubation in the presence of 5% CO2, or the combination of these two factors resulted in the stimulation of TSST-1 production. PMID:3793877

  6. Development of a syringe pump assisted dynamic headspace sampling technique for needle trap device

    Microsoft Academic Search

    In-Yong Eom; Vadoud H. Niri; Janusz Pawliszyn

    2008-01-01

    This paper describes a new approach that combines needle trap devices (NTDs) with a dynamic headspace sampling technique (purge and trap) using a bidirectional syringe pump. The needle trap device is a 22-G stainless steel needle 3.5-in. long packed with divinylbenzene sorbent particles. The same sized needle, without packing, was used for purging purposes. We chose an aqueous mixture of

  7. Detection of tissue properties using a piezoelectric vibration-based syringe

    NASA Astrophysics Data System (ADS)

    Lin, C. H.; Huang, Y. C.; Tsai, M. C.

    2012-12-01

    For safety improvement purposes, detection of tissue properties at the tip of the needle in real-time is helpful in controlling the movement of the needle in the operation of invasive surgical tools. According to the energy-based force model, the mechanical impedance of tissue can be represented approximately by a spring-damping model. In this study, a vibration-based syringe which adopts piezoelectric elements to vibrate the needle is proposed to identify tissue properties. In principle, by measuring the input electrical impedance of the vibration-based syringe, the mechanical impedance of tissue can be detected indirectly while the syringe exerts a vibration on the tissue. The model of the piezoelectric driven syringe and the procedure for evaluating the electromechanical interaction are given, and the mechanical impedance of tissue is evaluated by simulation. The proposed detection method has potential for applications of identifying tissue properties in epidural punctures and estimation of the degree of ablation in thermal surgery systems.

  8. cross infectionEvaluation of the effectiveness of decontamination of dental syringes

    Microsoft Academic Search

    K Vickery; A Pajkos; Y Cossart

    2000-01-01

    Aim Steam autoclaving is the gold standard for decontaminating dental instruments, but worldwide disinfection is still widely employed. We have evaluated a range of procedures for their ability to inactivate duck hepatitis B virus contaminating dental syringes.Methods Residual infectivity of virus suspensions following 2% glutaraldehyde treatment, ultrasonication or steam sterilisation at 121° or 134° was assayed by injecting day-old ducklings

  9. Residual Injection Risk Behavior, HIV Infection, and the Evaluation of Syringe Exchange Programs

    ERIC Educational Resources Information Center

    Des Jarlais, Don C.; Braine, Naomi; Yi, Huso; Turner, Charles

    2007-01-01

    This study assessed relationships between residual risk behavior (risk behavior among persons participating in effective HIV prevention programs) and HIV infection. Structured interviews and HIV tests were obtained from participants in six large U.S. syringe exchange programs. Program characteristics were obtained through interviews with the…

  10. Homicide by Sch from a syringe-like dart ejected by a compound crossbow.

    PubMed

    Guo, Wei; Luo, Guochang; Wang, Hao; Meng, Xiangzhi

    2015-02-01

    The compound crossbow can be used to eject syringe-like dart loaded with poisonous solution. Succinylcholine (Sch) is a short-acting neuromuscular blocker medically used to achieve complete relaxation of muscle for a good intubation condition. Without the help of an artificial respirator, intramuscular injection of a large dose of Sch can paralyze the respiratory muscle and result in the receiver's death. In this paper, we present the homicide case of a young male killed by Sch from a syringe-like dart ejected by a compound crossbow. The subcutaneous and muscular hemorrhages observed around the entry were more severe than that caused by a medical injection. Additionally, other autopsy results showed the external appearance of a pinhole, general asphyxia signs and pathological findings which were not characteristic. The discovery of a syringe-like dart at the scene is the critical clue and reason for analyzing for Sch, which is commonly used to load syringe-like dart to paralyze and steal dog in the countryside of China. PMID:25623191

  11. Autologous fat grafting: use of closed syringe microcannula system for enhanced autologous structural grafting

    PubMed Central

    Alexander, Robert W; Harrell, David B

    2013-01-01

    Objectives Provide background for use of acquiring autologous adipose tissue as a tissue graft and source of adult progenitor cells for use in cosmetic plastic surgery. Discuss the background and mechanisms of action of closed syringe vacuum lipoaspiration, with emphasis on accessing adipose-derived mesenchymal/stromal cells and the stromal vascular fraction (SVF) for use in aesthetic, structural reconstruction and regenerative applications. Explain a proven protocol for acquiring high-quality autologous fat grafts (AFG) with use of disposable, microcannula systems. Design Explain the components and advantage of use of the patented super luer-lock and microcannulas system for use with the closed-syringe system. A sequential explanation of equipment selection for minimally traumatic lipoaspiration in small volumes is presented, including use of blunt injection cannulas to reduce risk of embolism. Results Thousands of AFG have proven safe and efficacious for lipoaspiration techniques for large and small structural fat grafting procedures. The importance and advantages of gentle harvesting of the adipose tissue complex has become very clear in the past 5 years. The closed-syringe system offers a minimally invasive, gentle system with which to mobilize subdermal fat tissues in a suspension form. Resulting total nuclear counting of undifferentiated cells of the adipose-derived -SVF suggests that the yield achieved is better than use of always-on, constant mechanical pump applied vacuum systems. Conclusion Use of a closed-syringe lipoaspiration system featuring disposable microcannulas offers a safe and effective means of harvesting small volumes of nonmanipulated adipose tissues and its accompanying progenitor cells within the SVF. Closed syringes and microcannulas are available as safe, sterile, disposable, compact systems for acquiring high-quality AFG. Presented is a detailed, step-by-step, proven protocol for performing quality autologous structural adipose transplantation. PMID:23630430

  12. The effect of a new syringe design on the ability of rheumatoid arthritis patients to inject a biological medication.

    PubMed

    Sheikhzadeh, Ali; Yoon, Jangwhon; Formosa, Dan; Domanska, Barbara; Morgan, Darrell; Schiff, Michael

    2012-03-01

    Self-administration of new biological medications can be difficult for Rheumatoid Arthritis patients with functional impairment and hand and dexterity limitation. Twenty-three Rheumatoid Arthritis (RA) patients participated in this study to compare preferences and injection forces using a conventional syringe and a new ergonomically designed syringe. Injection force measurements were collected in two ways: a) isometric forces, with the syringes' plungers in fixed positions (depressed halfway and fully depressed), and b) forces exerted during injection of the medication. Subjects' grip and pinch strengths were measured. A perception questionnaire gauged subjects' impressions and preferences. Subjects were capable of exerting significantly higher isometric forces using the new syringe with the plunger fixed both halfway and fully depressed. During injection of the medication, peak and mean injection forces were significantly higher, and duration was shorter, when using the new syringe. Subjects rated the new syringe higher on all twenty attributes on preference and performance. Therefore, it is expected that the new syringe will benefit self-administration of medication injection for RA patients. PMID:21696704

  13. Fine-needle aspiration biopsy using a newly-developed pencil-grip syringe holder.

    PubMed

    Tao, L C; Smith, J W

    1999-02-01

    Until now, commercially available syringe holders for fine-needle aspiration (FNA) were designed to be held in a pistol-grip manner. A newly developed, pencil-grip syringe holder, the Tao Aspirator, was tested. The device is equipped with a release button for automatically drawing back the syringe plunger and a regulating knob for adjusting negative pressure for the aspiration. After direct smears were made for on-site examination, the remaining aspirated material was collected by rinsing the needle and syringe with CytoRich red fixative. Hettich cytocentrifuge preparations were then prepared. The quality of the first 150 FNA specimens procured by this device and prepared with liquid fixation was evaluated in terms of adequacy of specimen, amount of obscuring blood, preservation of cells, and ease of screening and interpretation. These 150 specimens included 32 from thyroids; 34 from breasts; 40 from lymph nodes; 24 from subcutaneous nodules; and 20 from salivary glands. There were no unsatisfactory specimens. In Hettich preparations, red blood cells were lysed, making interpretation easier. All cellular elements and tissue fragments were adequately fixed, showing excellent cellular morphology. Specimens fixed in liquid fixative yielded uniform cell suspensions, resulting in cytocentrifuge preparations with evenly distributed cells, and so the screening was also easier. The aspiration techniques using pistol-grip and pencil-grip FNA syringe holders were also compared in terms of control in tissue sampling, ease of use, and safety. The pencil-grip syringe holder allowed greater tactile sensation of the texture of the lesion, and enabled the operator to use a single hand to place a needle into a target lesion with minimal error. This device placed the hand relatively close to the needle tip while the hand was in a position of natural function, imparting more control in tissue sampling. It was more easily manipulated, and could prevent dripping when cystic fluid was aspirated. Specimen collection using the Tao Aspirator and processing with liquid fixation in addition to direct smear preparations allowed the laboratory to consistently produce adequate cytologic preparations and cell blocks. PMID:9951607

  14. Determination of pyrethroid metabolites in human urine using liquid phase microextraction coupled in-syringe derivatization followed by gas chromatography/electron capture detection.

    PubMed

    Lin, Chiu-Hwa; Yan, Cheing-Tong; Kumar, Ponnusamy Vinoth; Li, Hong-Ping; Jen, Jen-Fon

    2011-08-01

    Metabolites of synthetic pyrethroids such as cis-3-(2,2-dibromovinyl)-2,2-di-methylcyclo-propane-1-carboxylic acid, cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid), 3-phenoxybenzoic acid (3-PBA), and 4-fluoro-3-PBA are biomarkers for exposure to phenothrin, tetramethrin, cyfluthrin, cypermethrin, deltamethrin, and permethrin. In this study, the pyrethroid metabolites in workers' urine samples were monitored for the first time with a novel sample pretreatment process combining hollow fiber liquid phase microextraction (HF-LPME) and in-syringe derivatization (ISD) followed by gas chromatography-electron capture detector (GC-ECD) analysis. A micro-syringe pre-filled with derivatizing agents and syringe needle connected to an extracting solvent impregnated hollow fiber segment was used as the LPME probe. Pyrethroid metabolites were extracted and enriched simultaneously from urine samples by HF-LPME sampling and acid hydrolysis at 70 °C for 10 min. After sampling, the ISD was performed by mixing the extracting solution and derivatizing agents through plunger movements, followed by GC-ECD analysis. Parameters influencing the HF-LPME efficiency and ISD were investigated and optimized. Under optimum conditions, the method provided enrichment factors of 69.8-154.6, repeatability from 5.0 to 12% (n = 5), and good linearity (R(2) = 0.9980-0.9998) for interested analytes spiked in urine samples. The method detection limits ranged from 1.6 to 17 ng/mL. A comparison was performed between the proposed method and conventional methods. The proposed method was applied to analyze pyrethroid metabolites in the urine samples collected from workers of pesticide formulation plants. The results suggested that the proposed HF-LPME coupled ISD method was a rapid, simple, efficient, and eco-friendly technique in the biomonitoring of metabolites of pyrethroids in workers' urine. PMID:21667061

  15. Calculation of calibration figures and the volume correction factors for 90Y, 125I, 131I and 177Lu radionuclides based on Monte-Carlo ionization chamber simulation method

    NASA Astrophysics Data System (ADS)

    Kryeziu, D.; Tschurlovits, M.; Kreuziger, M.; Maringer, F.-J.

    2007-09-01

    Many metrology laboratories are dealing with activity measurements of different radionuclides with special interest in nuclear medicine as well as in radiopharmaceutical industry. In improving the accuracy of radionuclide activity measurements, a key role plays the calculation of calibration figures and the volume correction factors for the radionuclide under study. It is well known that the chamber calibration factors depend on the measurement geometry including the volume of the source and the type of the measurement vessel. In this work, the activity standards in the form of radioactive solutions are delivered in sealed Jena glass 5 ml FIOLAX ®-klar ampoule. Calculation of the calibration figures (or efficiencies) for 90Y, 125I, 131I and 177Lu radionuclides on 5 ml ampoule are presented in this paper. Additionally, their appropriate volume correction factors are determined. These calibration figures for the ISOCAL IV pressurized well re-entrant ionization chamber (IC) are pointed out based on the Monte-Carlo (MC) simulation method of such chamber using the PENELOPE-2005 MC computer simulation code. The chamber is filled with nitrogen gas pressurized to approximately 1 MPa. In determining the volume correction factors, the variation of calibration factors versus the mass of radioactive solution filling the 5 ml ampoule glass is investigated. From the point of view that impurity of 177 mLu isomer is always accompanying the 177Lu radionuclide, for making possible the correction due to presence of this impurity, the calibration factor and the volume correction factors for 177 mLu are reported as well.

  16. SU-E-I-22: Dependence On Calibration Phantom and Field Area of the Conversion Factor Used to Calculate Skin Dose During Neuro-Interventional Fluoroscopic Procedures

    SciTech Connect

    Rana, V K; Vijayan, S [Physiology and Biophysics, Toshiba Stroke and Vascular Research Center, University at Buffalo (State University of New York), Buffalo, NY (United States); Rudin, S R; Bednarek, D R [Department of Radiology, Physiology and Biophysics, Toshiba Stroke and Vascular Research Center, University at Buffalo (State University of New York), Buffalo, NY (United States)

    2014-06-01

    Purpose: To determine the appropriate calibration factor to use when calculating skin dose with our real-time dose-tracking system (DTS) during neuro-interventional fluoroscopic procedures by evaluating the difference in backscatter from different phantoms and as a function of entrance-skin field area. Methods: We developed a dose-tracking system to calculate and graphically display the cumulative skin-dose distribution in real time. To calibrate the DTS for neuro-interventional procedures, a phantom is needed that closely approximates the scattering properties of the head. We compared the x-ray backscatter from eight phantoms: 20-cm-thick solid water, 16-cm diameter water-filled container, 16-cm CTDI phantom, modified-ANSI head phantom, 20-cm-thick PMMA, Kyoto-Kagaku PBU- 50 head, Phantom-Labs SK-150 head, and RSD RS-240T head. The phantoms were placed on the patient table with the entrance surface at 15 cm tube-side from the isocenter of a Toshiba Infinix C-arm, and the entrance-skin exposure was measured with a calibrated 6-cc PTW ionization chamber. The measurement included primary radiation, backscatter from the phantom and forward scatter from the table and pad. The variation in entrance-skin exposure was also measured as a function of the skin-entrance area for a 30x30 cm by 20-cm-thick PMMA phantom and the SK-150 head phantom using four different added beam filters. Results: The entranceskin exposure values measured for eight different phantoms differed by up to 12%, while the ratio of entrance exposure of all phantoms relative to solid water showed less than 3% variation with kVp. The change in entrance-skin exposure with entrance-skin area was found to differ for the SK-150 head compared to the 20-cm PMMA phantom and the variation with field area was dependent on the added beam filtration. Conclusion: To accurately calculate skin dose for neuro-interventional procedures with the DTS, the phantom for calibration should be carefully chosen since different phantoms can contribute different backscatter for identical exposure parameters. Research supported in part by Toshiba Medical Systems and NIH Grants R43FD0158401, R44FD0158402 and R01EB002873.

  17. Appropriate sample bags and syringes for preserving breath samples in breath odor research: a technical note.

    PubMed

    Winkel, E G; Tangerman, A

    2008-03-01

    It is now generally accepted that the volatile sulfur compounds (VSCs) hydrogen sulfide, methyl mercaptan and dimethyl sulfide are the main contributors to halitosis when of oropharyngeal origin. The VSCs hydrogen sulfide and methyl mercaptan are the major causes of bad breath in oral malodour whereas dimethyl sulfide is generally the major cause of bad breath in extra-oral halitosis. To facilitate research in the field of halitosis, it is highly advantageous to be able to preserve breath samples for longer periods of time before measurement of the VSCs, e.g. for sampling patients at home or when studying a large cohort of patients where an immediate measurement of the VSCs is not possible. After testing numerous sample bags, ultimately the foil balloons, coated inside with the synthetic polymer polyethylene, were the preferred ones. All the VSCs in breath remained quite stable for at least 3 days in these balloons. Besides the sampling bags, the use of an appropriate syringe for sampling mouth air and for injecting samples in e.g. a gas chromatograph is also of great importance. Usually, syringes with a rubber barrel seal are used. However, some rubbers quickly adsorb the VSCs in breath. When preserving breath samples for longer periods, the rubber also releases VSCs, especially methyl mercaptan. It was also found that these syringes release a compound which interferes with dimethyl sulfide, when using gas chromatographic measurements with the OralChroma. We now use all-plastic syringes (B/Braun Injekt), made of polypropylene and polyethylene, in which the VSCs in breath remain quite stable for at least 9 h. PMID:21386155

  18. Compatibility and Stability of Dexamethasone Sodium Phosphate and Ketamine Hydrochloride Subcutaneous Infusions in Polypropylene Syringes

    Microsoft Academic Search

    David G. Watson; Mei Lin; Andrew Morton; Colin G. Cable; Dorothy A. McArthur

    2005-01-01

    The stability of ketamine hydrochloride injection and dexamethasone sodium phosphate injection, when mixed and stored in polypropylene syringes, was studied. Formulations containing ketamine hydrochloride (50 mg or 600 mg) and dexamethasone sodium phosphate (1 mg) in 0.9% sodium chloride injection (to 14 ml) were prepared and stored at 4°C, 23°C, and 37°C, under normal fluorescent light conditions, for 192 hours.

  19. The Impact of Legalizing Syringe Exchange Programs on Arrests Among Injection Drug Users in California

    PubMed Central

    Bluthenthal, Ricky N.; Lorvick, Jennifer; Anderson, Rachel; Flynn, Neil; Kral, Alex H.

    2007-01-01

    Legislation passed in 2000 allowed syringe exchange programs (SEPs) in California to operate legally if local jurisdictions declare a local HIV public health emergency. Nonetheless, even in locales where SEPs are legal, the possession of drug paraphernalia, including syringes, remained illegal. The objective of this paper is to examine the association between the legal status of SEPs and individual arrest or citation for drug paraphernalia among injection drug users (IDUs) in California from 2001 to 2003. Using data from three annual cross-sections (2001-03) of IDUs attending 24 SEPs in 16 California counties (N?=?1,578), we found that overall, 14% of IDUs in our sample reported arrest or citation for paraphernalia in the 6 months before the interview. Further analysis found that 17% of IDUs attending a legal SEP (defined at the county level) reported arrest or citation for drug paraphernalia compared to 10% of IDUs attending an illegal SEP (p?=?0.001). In multivariate analysis, the adjusted odds ratio of arrest or citation for drug paraphernalia was 1.6 [95% confidence interval (CI)?=?1.2, 2.3] for IDUs attending legal SEPs compared to IDUs attending illegal SEPs, after controlling for race/ethnicity, age, homelessness, illegal income, injection of amphetamines, years of injection drug use, frequency of SEP use, and number of needles received at last visit. IDUs attending SEPs with legal status may be more visible to police, and hence, more subject to arrest or citation for paraphernalia. These findings suggest that legislative efforts to decriminalize the operation of SEPs without concurrent decriminalization of syringe possession may result in higher odds of arrest among SEP clients, with potentially deleterious implications for the health and well-being of IDUs. More comprehensive approaches to removing barriers to accessing sterile syringes are needed if our public health goals for reducing new HIV/HCV infections are to be obtained. PMID:17265133

  20. Cloning and Sequencing of the Sphingomonas (Pseudomonas) paucimobilis Gene Essential for the O Demethylation of Vanillate and Syringate

    Microsoft Academic Search

    SEIJI NISHIKAWA; TOMONORI SONOKI; TATSUHIDE KASAHARA; TAKAHIRO OBI; SHOKO KUBOTA; SHINYA KAWAI; NORIYUKI MOROHOSHI; YOSHIHIRO KATAYAMA

    1998-01-01

    Sphingomonas (Pseudomonas) paucimobilis SYK-6 is able to grow on 5,5*-dehydrodivanillic acid (DDVA), syringate, vanillate, and other dimeric model compounds of lignin as a sole carbon source. Nitrosoguanidine mutagenesis of S. paucimobilis SYK-6 was performed, and two mutants with altered DDVA degradation pathways were isolated. The mutant strain NT-1 could not degrade DDVA, but could degrade syringate, vanillate, and 2,2*,3*-trihydroxy-3-methoxy-5,5*-dicarboxybiphenyl (OH-DDVA).

  1. Uncertainty of calibrations at the accredited dosimetry calibration laboratories.

    PubMed

    Ibbott, G S; Attix, F H; Slowey, T W; Fontenla, D P; Rozenfeld, M

    1997-08-01

    The American Association of Physicists in Medicine, through a subcommittee (formerly Task Group 3) of the Radiation Therapy Committee, has accredited five laboratories to perform calibrations of instruments used to calibrate therapeutic radiation beams. The role of the accredited dosimetry calibration laboratories (ADCLs) is to transfer a calibration factor from an instrument calibrated by the National Institute of Standards and Technology (NIST) to a customer's instrument. It is of importance to the subcommittee, to physicists using the services of the ADCLs, and to the ADCLs themselves, to know the uncertainty of instrument calibrations. The calibration uncertainty has been analyzed by asking the laboratories to provide information about their calibration procedures. Estimates of uncertainty by two procedures were requested: Type A are uncertainties derived as the standard deviations of repeated measurements, while type B are estimates of uncertainties obtained by other methods, again expressed as standard deviations. Data have been received describing the uncertainty of each parameter involved in calibrations, including those associated with measurements of charge, exposure time, and air density, among others. These figures were combined with the uncertainty of NIST calibrations, to arrive at an overall uncertainty which is expressed at the two-standard deviation level. For cable-connected instruments in gamma-ray and x-ray beams of HVL > 1 mm Al, the figure has an upper bound of approximately 1.2%. PMID:9284248

  2. In-coupled syringe assisted octanol-water partition microextraction coupled with high-performance liquid chromatography for simultaneous determination of neonicotinoid insecticide residues in honey.

    PubMed

    Vichapong, Jitlada; Burakham, Rodjana; Srijaranai, Supalax

    2015-07-01

    A simple and fast method namely in-coupled syringe assisted octanol-water partition microextraction combined with high performance liquid chromatography (HPLC) has been developed for the extraction, preconcentration and determination of neonicotinoid insecticide residues (e.g. imidacloprid, acetamiprid, clothianidin, thiacloprid, thiamethoxam, dinotefuran, and nitenpyram) in honey. The experimental parameters affected the extraction efficiency, including kind and concentration of salt, kind of disperser solvent and its volume, kind of extraction solvent and its volume, shooting times and extraction time were investigated. The extraction process was carried out by rapid shooting of two syringes. Therefore, rapid dispersion and mass transfer processes was created between phases, and thus affects the extraction efficiency of the proposed method. The optimum extraction conditions were 10.00mL of aqueous sample, 10% (w/v) Na2SO4, 1-octanol (100µL) as an extraction solvent, shooting 4 times and extraction time 2min. No disperser solvent and centrifugation step was necessary. Linearity was obtained within the range of 0.1-3000ngmL(-1), with the correlation coefficients greater than 0.99. The high enrichment factor of the target analytes was 100 fold and low limit of detection (0.25-0.50ngmL(-1)) could be obtained. This proposed method has been successfully applied in the analysis of neonicotinoid residues in honey, and good recoveries in the range of 96.93-107.70% were obtained. PMID:25882403

  3. Calibration of infusion pumps using liquids whose physical properties differ from those of water

    NASA Astrophysics Data System (ADS)

    Batista, E.; Furtado, A.; Almeida, N.; Moura, S.; Martins, R.; Sousa, L.; Filipe, E.

    2015-02-01

    Infusion medical devices are used in field applications, namely in clinical environments, here are used several types of liquids, according to the therapeutic to be administrated into the patient. In order to determine the influence of the fluids physical properties, such as viscosity and density and to produce an adequate reference liquid, tests were performed with a syringe pump, using the gravimetric method as reference calibration method.

  4. Image Calibration

    NASA Technical Reports Server (NTRS)

    Peay, Christopher S.; Palacios, David M.

    2011-01-01

    Calibrate_Image calibrates images obtained from focal plane arrays so that the output image more accurately represents the observed scene. The function takes as input a degraded image along with a flat field image and a dark frame image produced by the focal plane array and outputs a corrected image. The three most prominent sources of image degradation are corrected for: dark current accumulation, gain non-uniformity across the focal plane array, and hot and/or dead pixels in the array. In the corrected output image the dark current is subtracted, the gain variation is equalized, and values for hot and dead pixels are estimated, using bicubic interpolation techniques.

  5. Flow Calibration

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Flow Technology Inc. worked with Lewis Research Center to develop a system for monitoring two different propellants being supplied to a spacecraft rocket thruster. They then commercialized the technology in the Microtrack, an extremely precise low-flow calibration system. Moog Inc., one of the device's primary users, measures the flow rate or the speed at which hydraulic oil flows through pin sized holes in disc shaped sapphires with the Microtrack. Using this data, two orifices with exactly the same flow rate can be matched as a pair and used as masters in servovalve production. The microtrack can also be used to calibrate other equipment.

  6. Retention of 99mTc-DMSA(III) and 99mTc-nanocolloid in different syringes affects imaging quality.

    PubMed

    Bauwens, Matthias; Pooters, Ivo; van der Pol, Jochen; Mottaghy, Felix M; van Kroonenburgh, Marinus

    2014-04-01

    (99m)Tc-dimercaptosuccinic acid [DMSA(III)] and colloidal human serum albumin ((99m)Tc-nanocolloid) are widely used radiopharmaceuticals. Recently, in our institution we encountered image quality problems in DMSA scans after changing the brand of syringes we were using, which triggered us to look into the adsorption properties of syringes from different brands for (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid. We also describe a clinical case in which adsorption of (99m)Tc-DMSA(III) caused inferior imaging quality. DMSA and nanocolloid were labeled with (99m)Tc following manufacturer guidelines. After synthesis, syringes with (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid were stored for 15, 30, 60, and 120 min. We evaluated Luer Lock syringes manufactured by different brands such as Artsana, Henke-Sass-Wolf, B. Braun Medical N.V., CODAN Medizinische Geräte GmbH & Co KG, Becton Dickinson and Company, and Terumo Europe. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid was acceptably low for all syringes (<13%), except for two brands with (99m)Tc-DMSA(III) adsorption rates of 36 and 30%, respectively, and for one brand with a (99m)Tc-nanocolloid adsorption rate of 27%. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid reaches critical levels in syringes produced by two brands, potentially causing poor image quality--for example, in DMSA scans using pediatric radiopharmaceutical doses. It is advised to check the compatibility of any radiopharmaceutical with syringes as an integral part of the quality assurance program. PMID:24569706

  7. Taste and/or Odour Disturbances in Pediatric Patients Undergoing IV Flush with Normal Saline Administered by Prefilled Syringe

    PubMed Central

    Celetti, Steven J; Vaillancourt, Régis; Pascuet, Elena; Sharp, Diane

    2012-01-01

    Background: At the Children’s Hospital of Eastern Ontario, more than 6000 inpatients per year undergo IV saline flushes by prefilled syringe to assess and maintain patency of IV tubing. In studies involving adults, it has been reported that volatile substances may leach from syringe materials into the saline, leading to taste and/or odour disturbances. Objective: To determine the incidence of taste and/or odour disturbances in pediatric patients after flushing of IV tubing with 0.9% sodium chloride (normal saline [NS]) from prefilled syringes. Methods: Inpatients aged 5–18 years who had undergone routine flushing of central or peripheral IV tubing with commercially available prefilled NS syringes were interviewed. Children aged 5–10 years used a visual hedonic scale to rate taste and odour sensations, and those aged 11–18 years used a numeric rating scale. Results: During the study period (April to July 2011), a total of 104 pediatric inpatients (21 aged 5–10 years and 83 aged 11–18 years) underwent NS flushing of central (10 patients [10%]) or peripheral (94 patients [90%]) tubing. For 100 of these patients, BD Posiflush NaCl 0.9% 10-mL sterile prefilled syringes were used, and for 4 patients BD Saline XS NaCl 0.9% 10-mL sterile prefilled syringes were used. Taste and/or odour disturbances were reported by 76 (73%) of the patients. Twelve patients described more than one taste or odour sensation. Taste and odour disturbances were detected by children in both age groups. Conclusions: Flushing of IV tubing with prefilled NS syringes resulted in taste and/or odour disturbances in a pediatric population. PMID:23129865

  8. Raven Calibration

    NASA Astrophysics Data System (ADS)

    Pham, Laurie; Lardière, Olivier; Bradley, Colin

    2011-09-01

    Multi-Object Adaptive Optics (MOAO) is an adaptive optics technique in development for Extremely Large Telescopes and will allow simultaneous observation of up to 20 targets in a several arc-minute field-of-view. Raven is an MOAO pathfinder developed by the Adaptive Optics Laboratory of the University of Victoria, in collaboration with the Herzberg Institute of Astrophysics and the Subaru Telescope. Its goal is to demonstrate that MOAO technical challenges such as open-loop control and calibration are achievable on-sky and also to deliver science results. The open-loop (OL) approach makes the need for calibration even more crucial. We will present the specific calibration procedures of Raven in two steps. The first one is to find the command matrices between the three open-loop wavefront sensors (WFS) with the two deformable mirrors (DM) used to correct the wavefront on the science paths. Because of the OL, we add components such as a calibration-DM in front of the whole system and also close-loop WFS behind each DM. We register the DM with the CL-WFS and then the calibration-DM with all of the five WFS and then compute the command matrices. The goal of the second step is to remove the field-dependent non-common path aberrations (NCPAs). That task is common in AO systems but presents a bigger challenge in this case because of the longer optical paths, the open-loop control and also the moving pick-off arms.

  9. Aquagenic syringeal acrokeratoderma in an adult man: case report and review of the literature.

    PubMed

    Luo, D Q; Li, Y; Huang, Y B; Wu, L C; He, D Y

    2009-12-01

    Aquagenic syringeal acrokeratoderma (ASA) is a rare acquired disorder that develops predominantly in young women. It is clinically characterized by a burning sensation and whitish discolouration on the hands and rarely on the soles after brief immersion in water, which resolves within a short time after drying. Topical aluminium chloride and salicylic acid are reportedly beneficial in some cases. In total, 20 female and 8 male patients with ASA have been reported previously. We present another male patient, who failed to respond to treatment with antihistamines and topical steroids, but responded well to formalin 3% in alcohol without any side-effects. PMID:20055864

  10. Prospective effects of traumatic event re-exposure and PTSD in syringe exchange participants

    PubMed Central

    Peirce, Jessica M.; Brooner, Robert K.; Kolodner, Ken; Schacht, Rebecca L.; Kidorf, Michael S.

    2012-01-01

    Aim Determine the effect of traumatic event re-exposure and PTSD symptom severity on proximal drug use and drug abuse treatment-seeking in syringe exchange participants. Design Prospective longitudinal 16-month cohort study of new syringe exchange registrants enrolled in a parent study of methods to improve treatment engagement. Setting Data were collected in a research van next to mobile syringe exchange distribution sites in Baltimore, Maryland. Participants Male and female (N = 162) injecting drug users (IDUs) registered for syringe exchange. Measurements Traumatic event re-exposure was identified each month with the Traumatic Life Events Questionnaire. PTSD symptoms were measured with the Modified PTSD Symptom Scale-Revised, given every four months. Outcome measures collected monthly were days of drug use (heroin, cocaine) and drug abuse treatment-seeking behavior (interest, calls to obtain treatment, treatment participation). Findings Each traumatic event re-exposure was associated with about 1 more day of cocaine use after accounting for the previous month’s cocaine use [same month adjusted B(SE) = 1.16 (0.34); one month later: .99 (0.34)], while PTSD symptoms had no effect. Traumatic event re-exposure increased interest in drug abuse treatment [same month adjusted odds ratios with 95% confidence intervals = 1.34 (1.11–1.63)] and calling to obtain treatment [same month 1.58 (1.24–2.01); one month later 1.34 (1.03–1.75)]. Each 10% increase in PTSD symptom severity was associated with persistent increased interest in treatment [same month 1.25 (1.10–1.42); one month later 1.16 (1.02–1.32); two months later 1.15 (1.02–1.30)] and calling to obtain treatment [same month 1.16 (1.02–1.32)]. Neither traumatic events nor PTSD symptoms were associated with participants receiving treatment. Conclusions Becoming exposed again to traumatic events among injecting drug users is associated with an increase in cocaine use up to one month later, but drug use is not related to post-traumatic stress disorder symptoms. Both traumatic event re-exposure and posttraumatic stress disorder symptoms predict drug abuse treatment-seeking behavior for up to two months. PMID:22775291

  11. Surveillance of HIV, Hepatitis B Virus, and Hepatitis C Virus in an Estonian Injection Drug–Using Population: Sensitivity and Specificity of Testing Syringes for Public Health Surveillance

    PubMed Central

    Uusküla, Anneli; Heimer, Robert; DeHovitz, Jack; Fischer, Krista; McNutt, Louise-Anne

    2010-01-01

    Surveillance of bloodborne infections among injection drug users (IDUs) can be accomplished by determining the presence of pathogen markers in used syringes. Parallel testing of returned syringes and venous blood from IDUs was conducted to detect antibodies to human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). Syringe surveillance for HIV yielded a sensitivity and specificity of 92% and 89%, respectively, and provided a reasonable estimate of the prevalence of HIV among participants. Because sensitivity for HBV (34%) and HCV (55%) was low, syringe testing may be useful for surveillance of hepatitis over time but not for estimation of prevalence. PMID:16388495

  12. Accurate calibration of mercury vapour measurements.

    PubMed

    Brown, Richard J C; Brown, Andrew S

    2008-11-01

    Almost all measurements of mercury vapour, for example those to determine mass concentration in air, are currently ultimately traceable to the vapour pressure of mercury, usually via a bell-jar calibration apparatus. This allows a saturated concentration of mercury vapour in air to develop in a confined space in equilibrium with ambient conditions, from which a known mass of mercury can be removed for calibration purposes. Setting aside the uncertainty in the vapour pressure of mercury at a given temperature, the accuracy of vapour phase mercury determinations depends critically on fully understanding the operation and sensitivities of the mercury bell-jar apparatus. This paper discusses the thermodynamic and kinetic considerations that must be taken into account when using the bell-jar apparatus, provides the theoretical basis for understanding the operation of the bell-jar, and presents experimental data demonstrating the systematic biases which may be obtained if the bell-jar is used incorrectly. These biases depend on the temperature difference between the mercury vapour in the bell-jar and the syringe used to remove the mercury vapour from the bell-jar, but they may be well in excess of 10% under some operating conditions. The results from this study have been used to propose best practice solutions for mercury vapour calibrations using the bell-jar. PMID:18936841

  13. Antenna Calibration and Measurement Equipment

    NASA Technical Reports Server (NTRS)

    Rochblatt, David J.; Cortes, Manuel Vazquez

    2012-01-01

    A document describes the Antenna Calibration & Measurement Equipment (ACME) system that will provide the Deep Space Network (DSN) with instrumentation enabling a trained RF engineer at each complex to perform antenna calibration measurements and to generate antenna calibration data. This data includes continuous-scan auto-bore-based data acquisition with all-sky data gathering in support of 4th order pointing model generation requirements. Other data includes antenna subreflector focus, system noise temperature and tipping curves, antenna efficiency, reports system linearity, and instrument calibration. The ACME system design is based on the on-the-fly (OTF) mapping technique and architecture. ACME has contributed to the improved RF performance of the DSN by approximately a factor of two. It improved the pointing performances of the DSN antennas and productivity of its personnel and calibration engineers.

  14. Hand-powered microfluidics: A membrane pump with a patient-to-chip syringe interface

    PubMed Central

    Gong, Max M.; MacDonald, Brendan D.; Vu Nguyen, Trung; Sinton, David

    2012-01-01

    In this paper, we present an on-chip hand-powered membrane pump using a robust patient-to-chip syringe interface. This approach enables safe sample collection, sample containment, integrated sharps disposal, high sample volume capacity, and controlled downstream flow with no electrical power requirements. Sample is manually injected into the device via a syringe and needle. The membrane pump inflates upon injection and subsequently deflates, delivering fluid to downstream components in a controlled manner. The device is fabricated from poly(methyl methacrylate) (PMMA) and silicone, using CO2 laser micromachining, with a total material cost of ?0.20 USD/device. We experimentally demonstrate pump performance for both deionized (DI) water and undiluted, anticoagulated mouse whole blood, and characterize the behavior with reference to a resistor-capacitor electrical circuit analogy. Downstream output of the membrane pump is regulated, and scaled, by connecting multiple pumps in parallel. In contrast to existing on-chip pumping mechanisms that typically have low volume capacity (?5??L) and sample volume throughput (?1–10??l/min), the membrane pump offers high volume capacity (up to 240??l) and sample volume throughput (up to 125??l/min). PMID:24143160

  15. Lab-in-a-syringe using gold nanoparticles for rapid immunosensing of protein biomarkers.

    PubMed

    Nunes Pauli, Gisele Elias; de la Escosura-Muñiz, Alfredo; Parolo, Claudio; Helmuth Bechtold, Ivan; Merkoçi, Arben

    2015-01-21

    We have developed a paper and gold nanoparticle (AuNP)-based lab-in-a-syringe (LIS) for immunosensing of biomarkers. This simple diagnostic device features simultaneous sampling and vertical-flow operation, which means that unlike typical immunosensors, it does not suffer from any delay between sampling and detection. It can handle large-volume, low-concentration samples for analysis in diverse applications (e.g. biomedical, environmental, food, etc.). Furthermore, its operating range for sample concentration can be tuned by simply changing the volume of the syringed sample, which enables on-demand limits of detection (LOD). The LIS contains two nitrocellulose pads: the conjugate pad (which captures the analyte) and the detection pad (which signals the presence of the captured analyte) both embedded into reusable plastic cartridges. We demonstrated its efficiency in detecting human IgG (HIgG) (LOD: 1.0 ng mL(-1)) and prostate-specific antigen (PSA) (spiked urine samples; LOD: 1.9 ng mL(-1)). In the field, the LIS can be used for complete on-site analysis or to obtain partially analyzed samples (AuNPs with captured analyte) for subsequent detailed testing in specialized laboratories. PMID:25375810

  16. Attitudes of police officers towards syringe access, occupational needle-sticks, and drug use: A qualitative study of one city police department in the United States

    Microsoft Academic Search

    Leo Beletsky; Grace E. Macalino; Scott Burris

    2005-01-01

    Removal of legal barriers to syringe access has been identified as an important part of a comprehensive approach to reducing HIV transmission among injecting drug users (IDUs). Legal barriers include both “law on the books” and “law on the streets,” i.e., the actual practices of law enforcement officers. Changes in syringe and drug control policy can be ineffective in reducing

  17. Bundling occupational safety with harm reduction information as a feasible method for improving police receptiveness to syringe access programs: evidence from three U.S. cities

    Microsoft Academic Search

    Corey S Davis; Leo Beletsky

    2009-01-01

    INTRODUCTION: In light of overwhelming evidence that access to sterile injection equipment reduces incidence of injection-attributable bloodborne disease without encouraging drug use, many localities have authorized sterile syringe access programs (SAPs), including syringe exchange and pharmacy-based initiatives. Even where such interventions are clearly legal, many law enforcement officers are unaware of the public health benefits and legal status of these

  18. Determination of Zinc-Based Additives in Lubricating Oils by Flow-Injection Analysis with Flame-AAS Detection Exploiting Injection with a Computer-Controlled Syringe

    PubMed Central

    Pignalosa, Gustavo; Cabrera, Noel

    2005-01-01

    A flow-injection system is proposed for the determination of metal-based additives in lubricating oils. The system, operating under computer control uses a motorised syringe for measuring and injecting the oil sample (200 ?L) in a kerosene stream, where it is dispersed by means of a packed mixing reactor and carried to an atomic absorption spectrometer which is used as detector. Zinc was used as model analyte. Two different systems were evaluated, one for low concentrations (range 0–10 ppm) and the second capable of providing higher dilution rates for high concentrations (range 0.02%–0.2% w/w). The sampling frequency was about 30 samples/h. Calibration curves fitted a second-degree regression model (r 2 = 0.996). Commercial samples with high and low zinc levels were analysed by the proposed method and the results were compared with those obtained with the standard ASTM method. The t test for mean values showed no significant differences at the 95% confidence level. Precision (RSD%) was better than 5% (2% typical) for the high concentrations system. The carryover between successive injections was found to be negligible. PMID:18924720

  19. Calibration of circular loop antennas

    Microsoft Academic Search

    Aydin Aykan

    1998-01-01

    The calibration of a measuring loop antenna means assigning an antenna factor K for each frequency in the entire measurement band. Such a loop antenna factor can be found either by calculating the impedances of the loop, or by using a well-defined standard magnetic field of a transmitting antenna. For both methods, it is necessary to obtain an accurate relation

  20. Selective growth inhibition of human malignant melanoma cells by syringic acid-derived proteasome inhibitors

    PubMed Central

    2013-01-01

    Background It has been shown that proteasome inhibition leads to growth arrest in the G1 phase of the cell cycle and/or induction of apoptosis. However, it was found that some of these inhibitors do not induce apoptosis in several human normal cell lines. This selective activity makes proteasome inhibition a promising target for new generation of anticancer drugs. Clinical validation of the proteasome, as a therapeutic target in oncology, has been provided by the dipeptide boronic acid derivative; bortezomib. Bortezomib has proven to be effective as a single agent in multiple myeloma and some forms of non-Hodgkin’s lymphoma. Syringic acid (4-hydroxy-3,5-dimethoxybenzoic acid, 1), a known phenolic acid, was isolated from the methanol extract of Tamarix aucheriana and was shown to possess proteasome inhibitory activity. Methods Using Surflex-Dock program interfaced with SYBYL, the docking affinities of syringic acid and its proposed derivatives to 20S proteasome were studied. Several derivatives were virtually proposed, however, five derivatives: benzyl 4-hydroxy-3,5-dimethoxybenzoate (2), benzyl 4-(benzyloxy)-3,5-dimethoxybenzoate (3), 3'-methoxybenzyl 3,5-dimethoxy-4-(3'-methoxybenzyloxy)benzoate (4), 3'-methoxybenzyl 4-hydroxy-3,5-dimethoxybenzoate (5) and 3',5'-dimethoxybenzyl 4-hydroxy-3,5-dimethoxybenzoate (6), were selected based on high docking scores, synthesized, and tested for their anti-mitogenic activity against human colorectal, breast and malignant melanoma cells as well as normal human fibroblast cells. Results Derivatives 2, 5, and 6 showed selective dose-dependent anti-mitogenic effect against human malignant melanoma cell lines HTB66 and HTB68 with minimal cytotoxicity on colorectal and breast cancer cells as well as normal human fibroblast cells. Derivatives 2, 5 and 6 significantly (p???0.0001) inhibited the various proteasomal chymotrypsin, PGPH, and trypsin like activities. They growth arrested the growth of HTB66 cells at G1 and G2-phases. They also arrested the growth of HTB68 cells at S- and G2-phase, respectively. Moreover, derivatives 2, 5, and 6 markedly induced apoptosis (? 90%) in both HTB66 and HTB68. Conclusions Computer-derived syringic acid derivatives possess selective anti-mitogenic activity on human malignant melanoma cells that may be attributed to perturbation of cell cycle, induction of apoptosis and inhibition of various 26S proteasomal activities. PMID:23958424

  1. Factors relating to eating style, social desirability, body image and eating meals at home increase the precision of calibration equations correcting self-report measures of diet using recovery biomarkers: findings from the Women’s Health Initiative

    PubMed Central

    2013-01-01

    Background The extent to which psychosocial and diet behavior factors affect dietary self-report remains unclear. We examine the contribution of these factors to measurement error of self-report. Methods In 450 postmenopausal women in the Women’s Health Initiative Observational Study doubly labeled water and urinary nitrogen were used as biomarkers of objective measures of total energy expenditure and protein. Self-report was captured from food frequency questionnaire (FFQ), four day food record (4DFR) and 24 hr. dietary recall (24HR). Using regression calibration we estimated bias of self-reported dietary instruments including psychosocial factors from the Stunkard-Sorenson Body Silhouettes for body image perception, the Crowne-Marlowe Social Desirability Scale, and the Three Factor Eating Questionnaire (R-18) for cognitive restraint for eating, uncontrolled eating, and emotional eating. We included a diet behavior factor on number of meals eaten at home using the 4DFR. Results Three categories were defined for each of the six psychosocial and diet behavior variables (low, medium, high). Participants with high social desirability scores were more likely to under-report on the FFQ for energy (??=?-0.174, SE?=?0.054, p?calibration equations combining FFQ, 4DFR, 24HR with age, body mass index, race, and the psychosocial and diet behavior variables, the six psychosocial and diet variables explained 1.98%, 2.24%, and 2.15% of biomarker variation for energy, protein, and protein density respectively. The variations explained are significantly different between the calibration equations with or without the six psychosocial and diet variables for protein density (p?=?0.02), but not for energy (p?=?0.119) or protein intake (p?=?0.077). Conclusions The addition of psychosocial and diet behavior factors to calibration equations significantly increases the amount of total variance explained for protein density and their inclusion would be expected to strengthen the precision of calibration equations correcting self-report for measurement error. Trial registration ClinicalTrials.gov identifier: NCT00000611 PMID:23679960

  2. Taste and Odour Disturbances in Pediatric Patients Undergoing IV Flush with Normal Saline Administered by Prefilled or Freshly Prepared Syringes: Randomized Single-Blind Study

    PubMed Central

    Mancini, David; Vaillancourt, Régis; Pouliot, Annie; Lin, Alice; Sharp, Diane

    2014-01-01

    Background: Previous studies have reported the occurrence of taste and odour disturbances among patients undergoing IV flush with prefilled syringes of 0.9% sodium chloride (normal saline [NS]). These disturbances have been attributed to the leaching of volatile substances into the NS from the plastic of the syringe. To date, there have been no studies comparing the occurrence of taste and odour disturbances with different NS preparations. Objective: To compare the occurrence of taste and odour disturbances in pediatric patients undergoing IV flush with commercially available prefilled NS syringes and NS syringes prepared fresh daily. Methods: Patients aged 6 to 18 years who underwent routine flushing of central or peripheral IV tubing were asked to participate in this follow-up randomized single-blind study. Flushing was performed with NS from BD PosiFlush 10-mL sterile prefilled syringes or NS transferred from a polyolefin bag (Baxter AVIVA) to a polypropylene syringe and stored for a maximum of 12 h before use. Results: Fifty pediatric patients (mean age ± standard deviation 13.4 ± 3.8 years) who had undergone flushing of IV tubing with NS were interviewed. Taste or odour disturbances were reported by 18 (72%) of the 25 patients who underwent flushing with NS from a prefilled syringe, whereas only 1 (4%) of the 25 who underwent flushing with NS from a freshly prepared syringe experienced such disturbances (p < 0.001). Conclusions: There were significant differences in taste and odour disturbances experienced by patients who underwent IV flush with commercial prefilled NS syringes and freshly prepared NS syringes. PMID:25364017

  3. Portable system of programmable syringe pump with potentiometer for determination of promethazine in pharmaceutical applications

    PubMed Central

    Saleh, Tawfik A.; Abulkibash, A.M.; Ibrahim, Atta E.

    2011-01-01

    A simple and fast-automated method was developed and validated for the assay of promethazine hydrochloride in pharmaceutical formulations, based on the oxidation of promethazine by cerium in an acidic medium. A portable system, consisting of a programmable syringe pump connected to a potentiometer, was constructed. The developed change in potential during promethazine oxidation was monitored. The related optimum working conditions, such as supporting electrolyte concentration, cerium(IV) concentration and flow rate were optimized. The proposed method was successfully applied to pharmaceutical samples as well as synthetic ones. The obtained results were realized by the official British pharmacopoeia (BP) method and comparable results were obtained. The obtained t-value indicates no significant differences between the results of the proposed and BP methods, with the advantages of the proposed method being simple, sensitive and cost effective. PMID:23960787

  4. 78 FR 20116 - Draft Guidance for Industry and Food and Drug Administration Staff; Glass Syringes for Delivering...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ...FDA-2013-D-0362] Draft Guidance for Industry and Food and Drug Administration...availability of draft guidance for industry and FDA staff entitled...availability of a draft guidance for industry entitled ``Glass Syringes...has become aware of adverse events and product quality...

  5. Syringeal Specialization of Frequency Control during Song Production in the Bengalese Finch (Lonchura striata domestica)

    PubMed Central

    Secora, Kristen R.; Peterson, Jennifer R.; Urbano, Catherine M.; Chung, Boah; Okanoya, Kazuo; Cooper, Brenton G.

    2012-01-01

    Background Singing in songbirds is a complex, learned behavior which shares many parallels with human speech. The avian vocal organ (syrinx) has two potential sound sources, and each sound generator is under unilateral, ipsilateral neural control. Different songbird species vary in their use of bilateral or unilateral phonation (lateralized sound production) and rapid switching between left and right sound generation (interhemispheric switching of motor control). Bengalese finches (Lonchura striata domestica) have received considerable attention, because they rapidly modify their song in response to manipulations of auditory feedback. However, how the left and right sides of the syrinx contribute to acoustic control of song has not been studied. Methodology Three manipulations of lateralized syringeal control of sound production were conducted. First, unilateral syringeal muscular control was eliminated by resection of the left or right tracheosyringeal portion of the hypoglossal nerve, which provides neuromuscular innervation of the syrinx. Spectral and temporal features of song were compared before and after lateralized nerve injury. In a second experiment, either the left or right sound source was devoiced to confirm the role of each sound generator in the control of acoustic phonology. Third, air pressure was recorded before and after unilateral denervation to enable quantification of acoustic change within individual syllables following lateralized nerve resection. Significance These experiments demonstrate that the left sound source produces louder, higher frequency, lower entropy sounds, and the right sound generator produces lower amplitude, lower frequency, higher entropy sounds. The bilateral division of labor is complex and the frequency specialization is the opposite pattern observed in most songbirds. Further, there is evidence for rapid interhemispheric switching during song production. Lateralized control of song production in Bengalese finches may enhance acoustic complexity of song and facilitate the rapid modification of sound production following manipulations of auditory feedback. PMID:22479543

  6. Methyl syringate: a chemical marker of asphodel (Asphodelus microcarpus Salzm. et Viv.) monofloral honey.

    PubMed

    Tuberoso, Carlo I G; Bifulco, Ersilia; Jerkovi?, Igor; Caboni, Pierluigi; Cabras, Paolo; Floris, Ignazio

    2009-05-13

    During the liquid chromatographic study of the phenolic fraction of monofloral honeys was detected in the asphodel honey ( Asphodelus microcarpus Salzm. et Viv.) chromatogram a distinctive peak not detected in other monofloral honeys such as Arbutus unedo L., Hedysarum coronarium , Eucalyptus spp., and Galactites tomentosa . After thin layer chromatography (TLC) purification and characterization by NMR and LC-MS/MS, the compound was identified as methyl syringate (MSYR) and confirmed against an original standard. Levels of MSYR were measured in honeys of 2005, 2006, and 2007 by HPLC-DAD analysis. Level determination of MSYR was repeated in 2008 for 2006 and 2007 honeys to evaluate chemical stability of this phenolic compound. Levels of MSYR measured 1 year after the sampling did not show significant statistical differences (p < 0.05). The stability of MSYR was also confirmed by 12 asphodel honey samples collected in 2005 that showed amounts of methyl syringate comparable with those found in fresh honey. For the evaluation of MSYR origin, samples of nectars were collected from flowers and the content of MSYR was measured. Levels of MSYR in honeys are originated from the nectar with an average contribution of the nectar to the honey of 80%. Melissopalinological analysis did not allow the attribution of the honey monofloral origin because levels of asphodel pollen were <6% for all analyzed samples. Previously reported levels of MSYR for robinia, rape, chestnut, clover, linden blossom, dandelion, sunflower, thyme, manuka, and fir honeys were <5 mg/kg. For this reason, a minimum level of 122.6 mg/kg for MSYR in asphodel honeys can be considered as a chemical marker and, unlike the melissopalynological analysis, can be used for the origin attribution and to evaluate the percent of asphodel nectar in the honey. PMID:19309074

  7. Improving treatment enrollment and re-enrollment rates of syringe exchangers: 12-month outcomes

    PubMed Central

    Kidorf, Michael; King, Van L.; Gandotra, Neeraj; Kolodner, Ken; Brooner, Robert K.

    2012-01-01

    Background Developing bridges between community syringe exchange programs (SEPs) and substance abuse treatment could benefit syringe exchangers and the public health. Kidorf et al. (2009) showed that motivational approaches employed at an SEP site improved rates of treatment enrollment and reduced drug use over a 4-month observation window. The present study extends this report by evaluating rates of treatment enrollment and re-enrollment over a 12-month period. Methods Opioid dependent individuals (n = 281) newly registered at an SEP were randomly assigned to one of three referral interventions: 1) 8 individual motivational enhancement sessions and 16 treatment readiness group sessions designed to improve treatment interest and readiness (Motivated Referral Condition; MRC-only); 2) MRC-only with monetary incentives for attending sessions and enrolling in treatment (MRC+I); or 3) standard referral (SRC). MRC-only and MRC+I participants discharged from treatment could attend a treatment re-engagement group designed to facilitate return to treatment (MRC+I participants received incentives for attending sessions and re-enrolling in treatment). Results The 4-month outcomes generally extended over 12-months. MRC+I participants were more likely to enroll in methadone maintenance than MRC-only or SRC participants, and to re-enroll in treatment following discharge. MRC+I participants also reported more days of treatment and less heroin and injection use. Conclusions The good harm reduction outcomes for many SEP participants can be enhanced through strategies designed to facilitate treatment enrollment and re-enrollment. PMID:22209388

  8. A Syringe-Like Love Dart Injects Male Accessory Gland Products in a Tropical Hermaphrodite

    PubMed Central

    Koene, Joris M.; Liew, Thor-Seng; Montagne-Wajer, Kora; Schilthuizen, Menno

    2013-01-01

    Sexual conflict shapes the evolution of many behaviours and processes involved in reproduction. Nearly all evidence supporting this comes from species where the sexes are separated. However, a substantial proportion of animals and most plants are hermaphroditic, and theoretical work predicts that sexual conflict plays an important role even when the sexes are joined within one individual. This seems to have resulted in bizarre mating systems, sophisticated sperm packaging and complex reproductive morphologies. By far the best-known example of such a strategy in hermaphrodites is the shooting of so-called love-darts in land snails. All known love darts carry a gland product on their outside and enter this into the partner’s hemolymph by stabbing. Here, we show that species of the snail genus Everettia possess a syringe-like dart that serves as a real injection needle. Their dart is round in cross-section, contains numerous channels, and has perforations along its side. Histology and electron microscopy show that these holes connect to the channels inside the dart and run all the way up to the elaborate mucus glands that are attached to the dart sac. This is the first report on a love dart that is used as a syringe to directly inject the gland product into the partner’s hemolymph. Although the exact use and function of this dart remains to be demonstrated, this clearly adds to the complexity of the evolution of reproductive strategies in hermaphrodites in general. Moreover, the perforations on the outside of the love dart resemble features of other injection devices, thus uncovering common design and repeated evolution of such features in animals. PMID:23894565

  9. Parametric array calibration 

    E-print Network

    Wan, Shuang

    2011-01-01

    The subject of this thesis is the development of parametric methods for the calibration of array shape errors. Two physical scenarios are considered, the online calibration (self-calibration) using far-field sources and ...

  10. Are major reductions in new HIV infections possible with people who inject drugs? The case for low dead-space syringes in highly affected countries.

    PubMed

    Zule, William A; Cross, Harry E; Stover, John; Pretorius, Carel

    2013-01-01

    Circumstantial evidence from laboratory studies, mathematical models, ecological studies and bio behavioural surveys, suggests that injection-related HIV epidemics may be averted or reversed if people who inject drugs (PWID) switch from using high dead-space to using low dead-space syringes. In laboratory experiments that simulated the injection process and rinsing with water, low dead space syringes retained 1000 times less blood than high dead space syringes. In mathematical models, switching PWID from high dead space to low dead space syringes prevents or reverses injection-related HIV epidemics. No one knows if such an intervention is feasible or what effect it would have on HIV transmission among PWID. Feasibility studies and randomized controlled trials (RCTs) will be needed to answer these questions definitively, but these studies will be very expensive and take years to complete. Rather than waiting for them to be completed, we argue for an approach similar to that used with needle and syringe programs (NSP), which were promoted and implemented before being tested more rigorously. Before implementation, rapid assessments that involve PWID will need to be conducted to ensure buy-in from PWID and other local stakeholders. This commentary summarizes the existing evidence regarding the protective effects of low dead space syringes and estimates potential impacts on HIV transmission; it describes potential barriers to transitioning PWID from high dead space to low dead space needles and syringes; and it presents strategies for overcoming these barriers. PMID:22884539

  11. Absolute calibration in vivo measurement systems

    SciTech Connect

    Kruchten, D.A.; Hickman, D.P.

    1991-02-01

    Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs.

  12. POLARIMETRIC MICROWAVE RADIOMETER CALIBRATION

    E-print Network

    Ruf, Christopher

    POLARIMETRIC MICROWAVE RADIOMETER CALIBRATION by Jinzheng Peng A dissertation submitted in partial.4 Real Aperture Radiometer ................................................................................... 22 1.6 Radiometer Calibration

  13. Simple Syringe Filtration Methods for Reliably Examining Dissolved and Colloidal Trace Element Distributions in Remote Field Locations

    NASA Astrophysics Data System (ADS)

    Shiller, A. M.

    2002-12-01

    Methods for obtaining reliable dissolved trace element samples frequently utilize clean labs, portable laminar flow benches, or other equipment not readily transportable to remote locations. In some cases unfiltered samples can be obtained in a remote location and transported back to a lab for filtration. However, this may not always be possible or desirable. Additionally, methods for obtaining information on colloidal composition are likewise frequently too cumbersome for remote locations as well as being time-consuming. For that reason I have examined clean methods for collecting samples filtered through 0.45 and 0.02 micron syringe filters. With this methodology, only small samples are collected (typically 15 mL). However, with the introduction of the latest generation of ICP-MS's and microflow nebulizers, sample requirements for elemental analysis are much lower than just a few years ago. Thus, a determination of a suite of first row transition elements is frequently readily obtainable with samples of less than 1 mL. To examine the "traditional" (<0.45 micron) dissolved phase, 25 mm diameter polypropylene syringe filters and all polyethylene/polypropylene syringes are utilized. Filters are pre-cleaned in the lab using 40 mL of approx. 1 M HCl followed by a clean water rinse. Syringes are pre-cleaned by leaching with hot 1 M HCl followed by a clean water rinse. Sample kits are packed in polyethylene bags for transport to the field. Results are similar to results obtained using 0.4 micron polycarbonate screen filters, though concentrations may differ somewhat depending on the extent of sample pre-rinsing of the filter. Using this method, a multi-year time series of dissolved metals in a remote Rocky Mountain stream has been obtained. To examine the effect of colloidal material on dissolved metal concentrations, 0.02 micron alumina syringe filters have been utilized. Other workers have previously used these filters for examining colloidal Fe distributions in lake and sea water. Filters are pre-cleaned in the lab using clean pH 2 water followed by a clean water rinse and then dried with clean air. Because of the significant pressure that must be placed on the syringe for some minutes to effect a filtration, a simple plastic press and stand has been devised. Polarization artifacts, which can affect this type of ultra-filtration, do not appear to be significant. This may be due to the comparatively large pore size of these filters (equivalent to approx. 40 kDa). These filters, in combination with the 0.45 micron filters, are being used in a multi-year study of trace elements in the Yukon River system.

  14. The efficiency calibration and development of environmental correction factors for an in situ high-resolution gamma spectroscopy well logging system

    SciTech Connect

    Giles, J.R.

    1996-05-01

    A Gamma Spectroscopy Logging System (GSLS) has been developed to study sub-surface radionuclide contamination. Absolute efficiency calibration of the GSLS was performed using simple cylindrical borehole geometry. The calibration source incorporated naturally occurring radioactive material (NORM) that emitted photons ranging from 186-keV to 2,614-keV. More complex borehole geometries were modeled using commercially available shielding software. A linear relationship was found between increasing source thickness and relative photon fluence rates at the detector. Examination of varying porosity and moisture content showed that as porosity increases, relative photon fluence rates increase linearly for all energies. Attenuation effects due to iron, water, PVC, and concrete cylindrical shields were found to agree with previous studies. Regression analyses produced energy-dependent equations for efficiency corrections applicable to spectral gamma-ray well logs collected under non-standard borehole conditions.

  15. Technical communication: design and in vitro testing of a pressure-sensing syringe for endotracheal tube cuffs.

    PubMed

    Slocum, Alexander H; Slocum, Alexander H; Spiegel, Joan E

    2012-05-01

    Endotracheal intubation is a frequently performed procedure in the prehospital setting, intensive care unit, and for patients undergoing surgery. The endotracheal tube cuff must be inflated to a pressure that prevents air leaks without compromising tracheal mucosal blood flow. For simultaneous endotracheal tube cuff inflation and measurement, we designed and tested a novel pressure-sensing syringe in vitro. The prototype was developed using a standard 10-mL polycarbonate syringe body that houses a plunger and a silicone rubber bellows, the pressure-sensing element. Bellow feasibility was determined and modeled using finite element analysis. Repeatability testing at each pressure measurement for each bellows (pressure versus deflection) was within an average standard deviation of 0.3 cm to 1.61 cm (1%-5% error). Using an aneroid manometer for comparison, there was excellent linear correlation with a Spearman rank of 0.99 (P < 0.001), up to 30 cm H(2)O. PMID:22492187

  16. “Associations of Serum Insulin-like Growth Factor (IGF-I) and IGFBP-3 Levels Biomarker-Calibrated Protein, Dairy, and Milk Intake in the Women's Health Initiative”1

    PubMed Central

    Beasley, Jeannette M.; Gunter, Marc J.; LaCroix, Andrea Z.; Prentice, Ross L.; Neuhouser, Marian L.; Tinker, Lesley F.; Vitolins, Mara Z.; Strickler, Howard D.

    2014-01-01

    It is well-established that protein-energy malnutrition decreases serum insulin-like growth factor (IGF-I) levels, and supplementation of 30 grams of whey protein daily increased serum IGF-1 levels by 8% after 2 years in a clinical trial(1). Cohort studies provide the opportunity to assess associations between dietary protein intake and the IGF-axis under more typical eating conditions. We studied the associations of circulating IGF-axis protein levels (ELISA, Diagnostic Systems Laboratories) with total biomarker-calibrated protein intake, as well as dairy and milk intake, among postmenopausal women enrolled in the Women's Health Initiative (n=747). Analyses were conducted using multivariate linear regression models that adjusted for age, BMI, race/ethnicity, education, biomarker-calibrated energy, alcohol, smoking, physical activity, and hormone therapy use. There was a positive association between milk intake and free-IGF-1. A 3 serving increase in milk intake per day (~30 grams of protein) was associated with an estimated average 18.6% higher increase in free IGF-1 (95% CI 0.9% to 39.3%). Total IGF-I and IGFBP-3, however, were not associated with milk consumption, nor were there associations between biomarker-calibrated protein intake, biomarker-calibrated energy, and free IGF-I, total IGF-I, or IGFBP-3. This study of postmenopausal women is consistent with clinical trial data suggesting a specific relationship between milk consumption and serum IGF-I levels; albeit, in our dataset, this association was only statistically significant for free, but not total, IGF-I nor IGFBP-3. PMID:24094144

  17. Factorize

    NSDL National Science Digital Library

    Visualize factors through building rectangular areas on a grid. First enter all the factorizations of a number, then draw each factor set as an area on the grid. Factorize is one of the Interactivate assessment explorers.

  18. Syringic Acid Extracted from Herba dendrobii Prevents Diabetic Cataract Pathogenesis by Inhibiting Aldose Reductase Activity

    PubMed Central

    Wei, Xiaoyong; Chen, Dan; Yi, Yanchun; Qi, Hui; Gao, Xinxin; Fang, Hua; Gu, Qiong; Wang, Ling; Gu, Lianquan

    2012-01-01

    Objective. Effects of Syringic acid (SA) extracted from dendrobii on diabetic cataract (DC) pathogenesis were explored. Methods. Both in vitro and in vivo DC lens models were established using D-gal, and proliferation of HLEC exposed to SA was determined by MMT assay. After 60-day treatment with SA, rat lens transparency was observed by anatomical microscopy using a slit lamp. SA protein targets were extracted and isolated using 2-DE and MALDI TOF/TOF. AR gene expression was investigated using qRT-PCR. Interaction sites and binding characteristics were determined by molecule-docking techniques and dynamic models. Results. Targeting AR, SA provided protection from D-gal-induced damage by consistently maintaining lens transparency and delaying lens turbidity development. Inhibition of AR gene expression by SA was confirmed by qRT-PCR. IC50 of SA for inhibition of AR activity was 213.17??g/mL. AR-SA binding sites were Trp111, His110, Tyr48, Trp20, Trp79, Leu300, and Phe122. The main binding modes involved hydrophobic interactions and hydrogen bonding. The stoichiometric ratio of non-covalent bonding between SA and AR was 1.0 to 13.3. Conclusion. SA acts to prevent DC in rat lenses by inhibiting AR activity and gene expression, which has potential to be developed into a novel drug for therapeutic management of DC. PMID:23365598

  19. A laser syringe aimed at delivering drug into the outer layer of human skin

    NASA Astrophysics Data System (ADS)

    Yoh, Jack J.; Jang, Hun-jae; Park, Mi-ae; Han, Tae-hee; Hah, Jung-moo

    2012-07-01

    A desire to eliminate hypodermic needle in transdermal drug delivery may now be realized. Imaging of the skin after injection of fluorescent probe and biotin via the bio-ballistic technique revealed the epidermal and dermal layers which were stained well below 60 ?m underneath the abdominal skin of the guinea-pig. An extensive network of cells are shown in the deeper layer of the stained dermis as the distributed fluorescein isothiocyanate (FITC) dose is administered by repeated injection via the laser-based microjet. Here, we show our method of laser-based microjet drug delivery is capable of breaching guinea-pig's skin tissue and then delivering controlled dose of drug to the targeted region between 10 to 400 ?m underneath the outermost layer of the skin. While minimizing pain and tissue damage by reducing the injection volume to ˜100 nl per pulse and the microjet diameter of half the conventional syringe needle in 100 ?m, the optimally controlled delivery of liquid drug by the irradiated laser pulse is shown possible.

  20. Syringic Acid Extracted from Herba dendrobii Prevents Diabetic Cataract Pathogenesis by Inhibiting Aldose Reductase Activity.

    PubMed

    Wei, Xiaoyong; Chen, Dan; Yi, Yanchun; Qi, Hui; Gao, Xinxin; Fang, Hua; Gu, Qiong; Wang, Ling; Gu, Lianquan

    2012-01-01

    Objective. Effects of Syringic acid (SA) extracted from dendrobii on diabetic cataract (DC) pathogenesis were explored. Methods. Both in vitro and in vivo DC lens models were established using D-gal, and proliferation of HLEC exposed to SA was determined by MMT assay. After 60-day treatment with SA, rat lens transparency was observed by anatomical microscopy using a slit lamp. SA protein targets were extracted and isolated using 2-DE and MALDI TOF/TOF. AR gene expression was investigated using qRT-PCR. Interaction sites and binding characteristics were determined by molecule-docking techniques and dynamic models. Results. Targeting AR, SA provided protection from D-gal-induced damage by consistently maintaining lens transparency and delaying lens turbidity development. Inhibition of AR gene expression by SA was confirmed by qRT-PCR. IC(50) of SA for inhibition of AR activity was 213.17??g/mL. AR-SA binding sites were Trp111, His110, Tyr48, Trp20, Trp79, Leu300, and Phe122. The main binding modes involved hydrophobic interactions and hydrogen bonding. The stoichiometric ratio of non-covalent bonding between SA and AR was 1.0 to 13.3. Conclusion. SA acts to prevent DC in rat lenses by inhibiting AR activity and gene expression, which has potential to be developed into a novel drug for therapeutic management of DC. PMID:23365598

  1. Single crystal growth of InBi 1- xSe x by syringe pulling method

    NASA Astrophysics Data System (ADS)

    Shah, Dimple; Pandya, Girish; Vyas, Sandip; Jani, Maunik; Jariwala, Bhakti

    2010-04-01

    In recent years, III-V compounds have received some attention as potential candidates for infrared application in the 8-12 ?m range. Single crystal of InBi:Se belonging to the same system has been grown by Syringe pulling method. The charge was allowed to cool freely to room temperature, which took about 10 min. The stainless steel needle serves as heat sink and site of nucleation. Crystals were cleaved along the cleavage plane (0 0 1) parallel to the vertical growth axis. Growth features were studied on the surface of crystals. XRD technique has been used for testing the presence of constituent element of InBi:Se single crystal. Standard test for a new dislocation etchant has been carried out successfully and results are reported. The optical absorption was measured in the wave number range 500-4000 cm -1. The bandgap has been evaluated from these data and studied as a function of concentration. The increase in concentration has been also found to affect their hardness.

  2. Distribution of silicone oil in prefilled glass syringes probed with optical and spectroscopic methods.

    PubMed

    Wen, Zai-Qing; Vance, Aylin; Vega, Fabian; Cao, Xiaolin; Eu, Bruce; Schulthesis, Robert

    2009-01-01

    Prefilled glass syringes (PFSs) have become the most commonly used device for the delivery of recombinant protein therapeutics in parenteral formulations. In particular, auto-injectors preloaded with PFSs greatly facilitate the convenient and efficient self-administration of protein therapeutics by patients. Silicone oil is used as a lubricant in PFSs to facilitate the smooth motion of the plunger during injection. However, there have been few sophisticated analytical techniques that can qualitatively and quantitatively characterize in-situ the morphology, thickness, and distribution of silicone oil in PFSs. In this paper, we demonstrate the application of three optical techniques including confocal Raman microscopy, Schlieren optics, and thin film interference reflectometry to visualize and characterize silicone oil distribution in PFS. The results showed that a container coating process could produce unevenly distributed silicone oil on the glass barrel of PFSs. An insufficiency of the amount of silicone oil on the glass barrel of a PFS can cause stalling when the device is preloaded into an auto-injector. These analytical techniques can be applied to monitor the silicone oil distribution in PFSs. PMID:19634353

  3. Functional evaluation and characterization of a newly developed silicone oil-free prefillable syringe system.

    PubMed

    Yoshino, Keisuke; Nakamura, Koji; Yamashita, Arisa; Abe, Yoshihiko; Iwasaki, Kazuhiro; Kanazawa, Yukie; Funatsu, Kaori; Yoshimoto, Tsuyoshi; Suzuki, Shigeru

    2014-05-01

    The functionality of a newly developed silicone oil-free (SOF) syringe system, of which the plunger stopper is coated by a novel coating technology (i-coating™), was assessed. By scanning electron microscopy observations and other analysis, it was confirmed that the plunger stopper surface was uniformly covered with the designed chemical composition. A microflow imaging analysis showed that the SOF system drastically reduced both silicone oil (SO) doplets and oil-induced aggregations in a model protein formulation, whereas a large number of subvisible particles and protein aggregations were formed when a SO system was used. Satisfactory container closure integrity (CCI) was confirmed by means of dye and microorganism penetration studies. Furthermore, no significant difference between the break loose and gliding forces was observed in the former, and stability studies revealed that the SOF system could perfectly show the aging independence in break loose force observed in the SO system. The results suggest that the introduced novel SOF system has a great potential and represents an alternative that can achieve very low subvisible particles, secure CCI, and the absence of a break loose force. In particular, no risk of SO-induced aggregation can bring additional value in the highly sensitive biotech drug market. PMID:24643749

  4. A new syringe pump apparatus for the retrieval and temporal analysis of helium in groundwaters and geothermal fluids

    NASA Astrophysics Data System (ADS)

    Barry, P. H.; Hilton, D. R.; Tryon, M. D.; Brown, K. M.; Kulongoski, J. T.

    2009-05-01

    We present details of a newly designed syringe pump apparatus for the retrieval and temporal analysis of helium (SPARTAH). The device is composed of a commercially available syringe pump connected to coils of Cu tubing, which interface the syringe and the groundwater or geothermal wellhead. Through test deployments at geothermal wells in Iceland and California, we show that well fluids are drawn smoothly, accurately, and continuously into the Cu tubing and can be time-stamped through user-determined operating parameters. In the laboratory, the tubing is sectioned to reveal helium (He) characteristics of the fluids at times and for durations of interest. The device is capable of prolonged deployments, up to 6 months or more, with minimal maintenance. It can be used to produce detailed time series records of He, or any other geochemical parameter, in groundwaters and geothermal fluids. SPARTAH has application in monitoring projects assessing the relationship between external transient events (e.g., earthquakes) and geochemical signals in aqueous fluids.

  5. A new syringe pump apparatus for the retrieval and temporal analysis of helium in groundwaters and geothermal fluids

    USGS Publications Warehouse

    Barry, P.H.; Hilton, D.R.; Tryon, M.D.; Brown, K.M.; Kulongoski, J.T.

    2009-01-01

    [1] We present details of a newly designed syringe pump apparatus for the retrieval and temporal analysis of helium (SPARTAH). The device is composed of a commercially available syringe pump connected to coils of Cu tubing, which interface the syringe and the groundwater or geothermal wellhead. Through test deployments at geothermal wells in Iceland and California, we show that well fluids are drawn smoothly, accurately, and continuously into the Cu tubing and can be time-stamped through user-determined operating parameters. In the laboratory, the tubing is sectioned to reveal helium (He) characteristics of the fluids at times and for durations of interest. The device is capable of prolonged deployments, up to 6 months or more, with minimal maintenance. It can be used to produce detailed time series records of He, or any other geochemical parameter, in groundwaters and geothermal fluids. SPARTAH has application in monitoring projects assessing the relationship between external transient events (e.g., earthquakes) and geochemical signals in aqueous fluids. ?? 2009 by the American Geophysical Union.

  6. Setting Up High-Throughput Low-Volume Sequencing and PCR Reactions Using an Automated System Equipped with Precision Glass Syringes and a Non-Contact Microsolenoid Dispenser

    Microsoft Academic Search

    Hui-Chung Wu; Alex James; Nelson Braunthal; Jean Shieh; Arezou Azarani

    2003-01-01

    The advantages of using a new automated system, the Hydra-Plus-One System equipped with 96 or 384 precision glass syringes and a non-contact microsolenoid dispenser, in setting up high-throughput low-volume sequencing reactions and PCR are described. Using the syringe-based dispenser, which is the Hydra-PP part of this system, wet dispenses of as small as 100 nL with CVs of less than

  7. The effect of pH on the transformation of syringic and vanillic acids by the laccases of Rhizoctonia praticola and Trametes versicolor

    Microsoft Academic Search

    A. Leonowicz; R. U. Edgehill; J.-M. Bollag

    1984-01-01

    Laccases (benzenediol: oxygen oxidoreductases, EC 1.10.3.2) from Rhizoctonia praticola and Trametes versicolor formed different products from syringic and vanillic acids at different pH values, but both enzymes generated the same chemicals at a particular pH. The products were separated by thin-layer and high-performance liquid chromatography. Four compounds were determined from syringic acid (m\\/z 168, 334, 350 and 486) at pH

  8. Randomized, Community-Based Pharmacy Intervention to Expand Services Beyond Sale of Sterile Syringes to Injection Drug Users in Pharmacies in New York City

    PubMed Central

    Amesty, Silvia; Rivera, Alexis V.; Harripersaud, Katherine; Turner, Alezandria; Fuller, Crystal M.

    2013-01-01

    Structural interventions may help reduce racial/ethnic disparities in HIV. In 2009 to 2011, we randomized pharmacies participating in a nonprescription syringe access program in minority communities to intervention (pharmacy enrolled and delivered HIV risk reduction information to injection drug users [IDUs]), primary control (pharmacy only enrolled IDUs), and secondary control (pharmacy did not engage IDUs). Intervention pharmacy staff reported more support for syringe sales than did control staff. An expanded pharmacy role in HIV risk reduction may be helpful. PMID:23865644

  9. Multi-syringe flow injection solid-phase extraction system for on-line simultaneous spectrophotometric determination of nitro-substituted phenol isomers.

    PubMed

    Manera, Matías; Miró, Manuel; Estela, José Manuel; Cerdà, Víctor

    2007-01-16

    In this paper, a time-based multi-syringe flow injection (MSFI) approach is proposed for automated disk-based sorbent extraction of three nitro-substituted phenol isomers (2-, 3-, and 4-nitrophenol) followed by on-line simultaneous determination of individual species by diode-array spectrophotometry. The method involves the on-line enrichment of the targeted analytes from an acidic medium containing 0.1 mol L(-1) HCl onto a co-polymeric sorbent material, and the concurrent removal of potentially interfering matrix components. The nitrophenol isomers are subsequently eluted with an alkaline solution (0.7 mol L(-1) NaOH), whereupon the eluate is delivered to a diode-array spectrophotometer for recording of the spectral data in the UV-vis region. Deconvolution of strongly overlapped spectra was conducted with multivariate regression models based on multiple linear regression calibration. The analytical performance of the chemometric algorithm was characterized by relative prediction errors and recoveries. The MSFI manifold was coupled to a multiposition selection valve to set a rugged analyzer that ensures minimum operational maintenance via exploitation of membrane switching protocols. As compared with earlier methods for isolation/pre-concentration of nitro-substituted phenols based on liquid-liquid extraction, the proposed flow-through disk-based system should be regarded as an environmentally friendly approach because the use of harmful organic solvents is circumvented. Under the optimized chemical and physical variables, the 3sigma(blank) detection limits for 2-, 3-, and 4-nitrophenol were 1.2, 3.2 and 0.3 micromol L(-1) for a sample loading volume of 1.5 mL, and the relative standard deviations were < or =5.0%. The flowing system, which is able to handle up to 135 samples automatically, was proven suitable for monitoring trace levels of the target isomers in mineral, tap, and seawater. PMID:17386472

  10. A semi-automatic microextraction in packed sorbent, using a digitally controlled syringe, combined with ultra-high pressure liquid chromatography as a new and ultra-fast approach for the determination of prenylflavonoids in beers.

    PubMed

    Gonçalves, João L; Alves, Vera L; Rodrigues, Fátima P; Figueira, José A; Câmara, José S

    2013-08-23

    In this work a highly selective and sensitive analytical procedure based on semi-automatic microextraction by packed sorbents (MEPS) technique, using a new digitally controlled syringe (eVol(®)) combined with ultra-high pressure liquid chromatography (UHPLC), is proposed to determine the prenylated chalcone derived from the hop (Humulus lupulus L.), xanthohumol (XN), and its isomeric flavonone isoxanthohumol (IXN) in beers. Extraction and UHPLC parameters were accurately optimized to achieve the highest recoveries and to enhance the analytical characteristics of the method. Important parameters affecting MEPS performance, namely the type of sorbent material (C2, C8, C18, SIL, and M1), elution solvent system, number of extraction cycles (extract-discard), sample volume, elution volume, and sample pH, were evaluated. The optimal experimental conditions involves the loading of 500?L of sample through a C18 sorbent in a MEPS syringe placed in the semi-automatic eVol(®) syringe followed by elution using 250?L of acetonitrile (ACN) in a 10 extractions cycle (about 5min for the entire sample preparation step). The obtained extract is directly analyzed in the UHPLC system using a binary mobile phase composed of aqueous 0.1% formic acid (eluent A) and ACN (eluent B) in the gradient elution mode (10min total analysis). Under optimized conditions good results were obtained in terms of linearity within the established concentration range with correlation coefficients (R) values higher than 0.986, with a residual deviation for each calibration point below 12%. The limit of detection (LOD) and limit of quantification (LOQ) obtained were 0.4ngmL(-1) and 1.0ngmL(-1) for IXN, and 0.9ngmL(-1) and 3.0ngmL(-1) for XN, respectively. Precision was lower than 4.6% for IXN and 8.4% for XN. Typical recoveries ranged between 67.1% and 99.3% for IXN and between 74.2% and 99.9% for XN, with relative standard deviations %RSD no larger than 8%. The applicability of the proposed analytical procedure in commercial beers, revealed the presence of both target prenylchalcones in all samples being IXN the most abundant with concentration of between 0.126 and 0.200?gmL(-1). PMID:23871283

  11. In-syringe magnetic-stirring-assisted liquid-liquid microextraction for the spectrophotometric determination of Cr(VI) in waters.

    PubMed

    Henríquez, Camelia; Horstkotte, Burkhard; Solich, Petr; Cerdà, Víctor

    2013-08-01

    A fully automated method for the determination of chromate is described. It is based on the selective reaction of Cr(VI) with diphenylcarbazide in acidic media to form a colored complex of Cr(III) with the oxidation product diphenylcarbazone. The reaction was performed within the syringe of an automatic burette containing a magnetic stirrer for homogenization of the sample and the required reagents. In-syringe stirring was made possible using a specially designed driving device placed around the syringe barrel to achieve a rotating magnetic field in the syringe, forcing the stirrer to spin. In a second step, the reaction mixture in the syringe was neutralized to allow in-syringe magnetic-stirring-assisted dispersive liquid-liquid microextraction of the complex into 125 ?L of n-hexanol. After phase separation by droplet flotation over 30 s, the organic phase was propelled into a coupled spectrophotometric detection cell. The entire multistep procedure including in-system standard preparation was done within 270 s. The method was used for the analysis of natural waters, achieving average analyte recovery of 103%, a limit of detection of 0.26 ?g L(-1), and a repeatability of less than 4% relative standard deviation. PMID:23812854

  12. Factoring

    NSDL National Science Digital Library

    Mr Clark

    2012-10-31

    Test your factoring skills Factors and Multiples Jeopardy How much do you know about factoring and multiples? Play Jeopardy and find out! Prime Factoring Turkey Shoot Blast these turkeys using your factoring skills. Help the Professor Super save the planet by "cooking" the Giant Frozen Turkeys of Destruction. Math Lines 12 X-Factor Shoot the ball at the other factors to get a product of 12. You can also ...

  13. Reduction of Systematic Errors in Diagnostic Receivers Through the Use of Balanced Dicke-Switching and Y-Factor Noise Calibrations

    SciTech Connect

    John Musson, Trent Allison, Roger Flood, Jianxun Yan

    2009-05-01

    Receivers designed for diagnostic applications range from those having moderate sensitivity to those possessing large dynamic range. Digital receivers have a dynamic range which are a function of the number of bits represented by the ADC and subsequent processing. If some of this range is sacrificed for extreme sensitivity, noise power can then be used to perform two-point load calibrations. Since load temperatures can be precisely determined, the receiver can be quickly and accurately characterized; minute changes in system gain can then be detected, and systematic errors corrected. In addition, using receiver pairs in a balanced approach to measuring X+, X-, Y+, Y-, reduces systematic offset errors from non-identical system gains, and changes in system performance. This paper describes and demonstrates a balanced BPM-style diagnostic receiver, employing Dicke-switching to establish and maintain real-time system calibration. Benefits of such a receiver include wide bandwidth, solid absolute accuracy, improved position accuracy, and phase-sensitive measurements. System description, static and dynamic modelling, and measurement data are presented.

  14. Implicit Spacecraft Gyro Calibration

    NASA Technical Reports Server (NTRS)

    Harman, Richard; Bar-Itzhack, Itzhack Y.

    2003-01-01

    This paper presents an implicit algorithm for spacecraft onboard instrument calibration, particularly to onboard gyro calibration. This work is an extension of previous work that was done where an explicit gyro calibration algorithm was applied to the AQUA spacecraft gyros. The algorithm presented in this paper was tested using simulated data and real data that were downloaded from the Microwave Anisotropy Probe (MAP) spacecraft. The calibration tests gave very good results. A comparison between the use of the implicit calibration algorithm used here with the explicit algorithm used for AQUA spacecraft indicates that both provide an excellent estimation of the gyro calibration parameters with similar accuracies.

  15. Calibrated Peer Review

    NSDL National Science Digital Library

    What is Calibrated Peer ReviewTM? Calibrated Peer ReviewTM (CPR) (more info) is a web-based writing and peer review tool free to instructors and their classes. Students write short essays on a given topic following ...

  16. Spreader Calibration for Turfgrass

    E-print Network

    Taylor, Gene R.; Abernathy, Scott

    1999-12-08

    To apply pesticides and fertilizers on turfgrass properly, you must have accurately calibrated equipment. This publication explains how to calibrate rotary and drop spreaders. A list of spreader operation tips is included....

  17. Analytical multicollimator camera calibration

    USGS Publications Warehouse

    Tayman, W.P.

    1978-01-01

    Calibration with the U.S. Geological survey multicollimator determines the calibrated focal length, the point of symmetry, the radial distortion referred to the point of symmetry, and the asymmetric characteristiecs of the camera lens. For this project, two cameras were calibrated, a Zeiss RMK A 15/23 and a Wild RC 8. Four test exposures were made with each camera. Results are tabulated for each exposure and averaged for each set. Copies of the standard USGS calibration reports are included. ?? 1978.

  18. Miniature Remote Deadweight Calibrator

    NASA Technical Reports Server (NTRS)

    Supplee, Frank H., Jr.; Tcheng, Ping

    1988-01-01

    Miniature, computer-controlled deadweight calibrator developed to calibrate remotely force transducer located in cryogenic chamber. Used with microcomputer, calibration system automatically applies deadweight loads to skin-friction balance, records and reduces data, and prints out results. Actuator controller and interlocking-weight system key elements in precise, automatic transducer calibrator. Designed for full-scale load of 1,000 mg. Concept extended to accommodate other full-scale load ranges.

  19. Calibrating Water System Models

    Microsoft Academic Search

    A. Lee Cesario; J. O. Davis

    1984-01-01

    Calibration enables a computer model to simulate field conditions accurately. Telemetry data and field measurements of the system provide base data for calibration, but computer programs that automatically extract and compare pertinent data with simulated values can aid the process. Once calibrated, the model can be used with a great degree of confidence as a predictor and as a benchmark

  20. Employee Development Calibrating Performance

    E-print Network

    Brodie III, Edmund D.

    and fair evaluation of an employee's performance by identifying potential supervisor and reviewer biasesEmployee Development Page 1 2009 Calibrating Performance What is calibration? Calibration is a two, the reviewers who examine the employee evaluations, and the executive to whom these individuals report

  1. SPI energy calibration

    E-print Network

    V. Lonjou; J. Knodlseder; J. P. Roques; G. K. Skinner; P. von Ballmoos; P. Jean; P. Paul; G. Weidenspointner; C. Wunderer; S. Schanne

    2005-04-14

    The status of the SPI energy calibration after the first year of INTEGRAL operations is reported. We have studied the gain variations and we have demonstrated that the most important parameter is the germanium detector temperature. This study permits us to determine the limits of our calibration method and the frequency of calibrations needed.

  2. Deformations Of Calibrated Submanifolds

    Microsoft Academic Search

    Robert C. Mclean

    1996-01-01

    . Assuming the ambient manifold is Kahler, the theory of complex submanifoldscan be placed in the more general context of calibrated submanifolds, see[HL]. It is therefore natural to try to extend some of the many results in complexgeometry to the other calibrated geometries of [HL]. In particular, the question ofdeformability of calibrated submanifolds is addressed here (analogous to Kodaira'swork on

  3. Assessment of MODIS Reflected Solar Calibration Uncertainty

    NASA Technical Reports Server (NTRS)

    Xiong, Xiaoxiong; Sun, Junqiang; Butler, James

    2011-01-01

    Determination of the calibration accuracy and traceability of a remote sensing instrument is a driving issue in the use of satellite data for calibration inter-comparisons and studying climate change. The Terra and Aqua MODerate Resolution Imaging Spectroradiometer (MODIS) instruments have successfully operated for more than 11 and 9 years, respectively. Twenty of the thirty six MODIS spectral bands are in the reflected solar region with center wavelengths ranging from 0.41 to 2.2 microns. MODIS reflective solar band (RSB) on-orbit calibration is reflectance based through the use of an on-board solar diffuser (SO). The calibration uncertainty requirements are +/-2.0% for the RSB reflectance factors at sensor specified typical scene reflectances or radiances. The SO bi-directional reflectance factor (BRF) was characterized pre-launch and its on-orbit changes are tracked by an on-board solar diffuser stability monitor (SDSM). This paper provides an assessment of MODIS RSB on-orbit calibration traceability and uncertainty for its Level 1B (L1B) reflectance factors. It examines in details each of the uncertainty contributors, including those from pre-launch measurements as well as on-orbit observations. Common challenging issues and differences due to individual sensors' specific characteristics and on-orbit performance are also discussed in this paper. Guidance and recommendations are presented, based on lessons from MODIS RSB calibration uncertainty assessment, for the development of future instrument calibration and validation plans.

  4. Nonlinear Observers for Gyro Calibration

    NASA Technical Reports Server (NTRS)

    Thienel, Julie; Sanner, Robert M.

    2003-01-01

    Nonlinear observers for gyro calibration are presented. The first observer estimates a constant gyro bias. The second observer estimates scale factor errors. The third observer estimates the gyro alignment for three orthogonal gyros. The convergence properties of all three observers are discussed. Additionally, all three observers are coupled with a nonlinear control algorithm. The stability of each of the resulting closed loop systems is analyzed. Simulated test results are presented for each system.

  5. SAR calibration - An overview

    NASA Technical Reports Server (NTRS)

    Freeman, Anthony

    1992-01-01

    Remote sensing with synthetic aperture radars (SAR's) is a rapidly developing field. Calibration of these sensors is required for the establishment of relationships between radar backscatter and geographical parameters. A review of recent progress in SAR calibration is presented. The quantities measured by SAR are defined and mathematical formulations of the three basic types of SAR images are developed. The establishment of scientific requirements for calibration and the difficulties involved are discussed. Image quality assessment is reviewed and the problems of radiometric calibration of SAR images using the radar equation and internal and external approaches are considered. Polarimetric radar calibration and the development of the necessary algorithms are described. Interferometric phase calibration and its associated problems are reviewed and future challenges in SAR calibration are discussed.

  6. Direct megavoltage photon calibration service in Australia.

    PubMed

    Butler, D J; Ramanathan, G; Oliver, C; Cole, A; Lye, J; Harty, P D; Wright, T; Webb, D V; Followill, D S

    2014-12-01

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) maintains the Australian primary standard of absorbed dose. Until recently, the standard was used to calibrate ionisation chambers only in (60)Co gamma rays. These chambers are then used by radiotherapy clinics to determine linac output, using a correction factor (k Q) to take into account the different spectra of (60)Co and the linac. Over the period 2010-2013, ARPANSA adapted the primary standard to work in megavoltage linac beams, and has developed a calibration service at three photon beams (6, 10 and 18 MV) from an Elekta Synergy linac. We describe the details of the new calibration service, the method validation and the use of the new calibration factors with the International Atomic Energy Agency's TRS-398 dosimetry Code of Practice. The expected changes in absorbed dose measurements in the clinic when shifting from (60)Co to the direct calibration are determined. For a Farmer chamber (model 2571), the measured chamber calibration coefficient is expected to be reduced by 0.4, 1.0 and 1.1 % respectively for these three beams when compared to the factor derived from (60)Co. These results are in overall agreement with international absorbed dose standards and calculations by Muir and Rogers in 2010 of k Q factors using Monte Carlo techniques. The reasons for and against moving to the new service are discussed in the light of the requirements of clinical dosimetry. PMID:25146559

  7. Direct megavoltage photon calibration service in Australia

    PubMed Central

    Ramanathan, G.; Oliver, C.; Cole, A.; Lye, J.; Harty, P. D.; Wright, T.; Webb, D. V.; Followill, D. S.

    2014-01-01

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) maintains the Australian primary standard of absorbed dose. Until recently, the standard was used to calibrate ionisation chambers only in 60Co gamma rays. These chambers are then used by radiotherapy clinics to determine linac output, using a correction factor (kQ) to take into account the different spectra of 60Co and the linac. Over the period 2010–2013, ARPANSA adapted the primary standard to work in megavoltage linac beams, and has developed a calibration service at three photon beams (6, 10 and 18 MV) from an Elekta Synergy linac. We describe the details of the new calibration service, the method validation and the use of the new calibration factors with the International Atomic Energy Agency’s TRS-398 dosimetry Code of Practice. The expected changes in absorbed dose measurements in the clinic when shifting from 60Co to the direct calibration are determined. For a Farmer chamber (model 2571), the measured chamber calibration coefficient is expected to be reduced by 0.4, 1.0 and 1.1 % respectively for these three beams when compared to the factor derived from 60Co. These results are in overall agreement with international absorbed dose standards and calculations by Muir and Rogers in 2010 of kQ factors using Monte Carlo techniques. The reasons for and against moving to the new service are discussed in the light of the requirements of clinical dosimetry. PMID:25146559

  8. Factorize

    NSDL National Science Digital Library

    2000-01-01

    This interactive applet allows a student to visually explore the concept of factors by creating different rectangular arrays for a number. The user constructs the array by clicking and dragging on a grid. The length and width of the array are factors of the number. A student can elect an option of a randomly selected number or the student selects his own number between 2 and 50. Exploration questions are included to promote student discovery of mathematical concepts with factors.

  9. Integrated lab-in-syringe platform incorporating a membraneless gas-liquid separator for automatic cold vapor atomic absorption spectrometry.

    PubMed

    Giakisikli, Georgia; Miró, Manuel; Anthemidis, Aristidis

    2013-10-01

    This manuscript reports the proof-of-concept of a novel integrated lab-in-syringe/gas-liquid separation (LIS/GLS) batch-flow system based on a programmable flow for automatic cold vapor atomic absorption spectrometric assays. Homogeneous mixing of metered volumes of sample and reagent solutions drawn up in a sandwich-type mode along with in situ vapor generation are accomplished inside the microsyringe in a closed manner, while the separation of vapor species is achieved via the membraneless GLS located at the top of the syringe's valve in the upright position. The potentials of the proposed manifold were demonstrated for trace inorganic mercury determination in drinking waters and seawater. For a 3.0 mL sample, the limit of detection and repeatability (RSD) were found to be 0.03 ?g L(-1) Hg(II) and 3.1% (at the 2.0 ?g L(-1) concentration level), respectively, with a dynamic range extending up to 10.0 ?g L(-1). The proposed system fulfills the requirements of US-EPA, WHO, and EU Council Directives for measurements of the maximum allowed concentrations of inorganic mercury in drinking water. PMID:23977837

  10. NIMBY localism and national inequitable exclusion alliances: The case of syringe exchange programs in the United States

    PubMed Central

    Tempalski, Barbara; Friedman, Risa; Keem, Marie; Cooper, Hannah; Friedman, Samuel R.

    2007-01-01

    Syringe exchange programs (SEPs) aim to reduce the harm associated with injection drug use (IDU). Although they have been accepted as critical components of HIV prevention in many parts of the world, they are often unwelcome and difficult to set up and maintain, even in communities hardest hit by IDU-related HIV transmission. This research examines socio-cultural and political processes that shape community and institutional resistance toward establishing and maintaining SEPs. These processes are configured and reinforced through the socio-spatial stigmatizing of IDUs, and legal and public policy against SEPs. Overarching themes the paper considers are: (1) institutional and/or political opposition based on (a) political and law enforcement issues associated with state drug paraphernalia laws and local syringe laws; (b) harassment of drug users and resistance to services for drug users by local politicians and police; and (c) state and local government (in)action or opposition; and (2) the stigmatization of drug users and location of SEPs in local neighborhoods and business districts. Rather than be explained by “not in my back yard” localism, this pattern seems best conceptualized as an “inequitable exclusion alliance” (IEA) that institutionalizes national and local stigmatizing of drug users and other vulnerable populations. PMID:18978931

  11. Needle and syringe sharing practices of injecting drug users participating in an outreach HIV prevention program in Tehran, Iran: A cross-sectional study

    PubMed Central

    Vazirian, Mohsen; Nassirimanesh, Bijan; Zamani, Saman; Ono-Kihara, Masako; Kihara, Masahiro; Mortazavi Ravari, Shahrzad; Gouya, Mohammad Mehdi

    2005-01-01

    HIV infection rates have reached epidemic proportions amongst injecting drug users (IDUs) in Iran. Although a number of community-based interventions have being implemented in the country, there is little information on the risk behaviors of IDU participants in these programs. This cross-sectional report aimed to compare the risk behaviors of injecting drug users with differential exposure rates to an HIV outreach program in Tehran, Iran. Results indicated that shared use of needle/syringe in the past month was significantly lower among IDUs who received estimated ? 7 syringes per week than those who did not [adjusted odds ratio (OR) = 14.36, 95% confidence interval (CI) 2.30–89.56]. While the effectiveness of this outreach program needs further evaluation through a longitudinal investigation, our preliminary findings suggest that the outreach program in Tehran may have been beneficial in reducing direct sharing among those who received more than several needles/syringes from the program. PMID:16212655

  12. Multidetector calibration for mass spectrometers

    SciTech Connect

    Bayne, C.K. [Oak Ridge National Lab., TN (United States); Donohue, D.L.; Fiedler, R. [IAEA, Seibersdorf (Austria). Safeguards Analytical Lab.

    1994-06-01

    The International Atomic Energy Agency`s Safeguards Analytical Laboratory has performed calibration experiments to measure the different efficiencies among multi-Faraday detectors for a Finnigan-MAT 261 mass spectrometer. Two types of calibration experiments were performed: (1) peak-shift experiments and (2) peak-jump experiments. For peak-shift experiments, the ion intensities were measured for all isotopes of an element in different Faraday detectors. Repeated measurements were made by shifting the isotopes to various Faraday detectors. Two different peak-shifting schemes were used to measure plutonium (UK Pu5/92138) samples. For peak-jump experiments, ion intensities were measured in a reference Faraday detector for a single isotope and compared with those measured in the other Faraday detectors. Repeated measurements were made by switching back-and-forth between the reference Faraday detector and a selected Faraday detector. This switching procedure is repeated for all Faraday detectors. Peak-jump experiments were performed with replicate measurements of {sup 239}Pu, {sup 187}Re, and {sup 238}U. Detector efficiency factors were estimated for both peak-jump and peak-shift experiments using a flexible calibration model to statistically analyze both types of multidetector calibration experiments. Calculated detector efficiency factors were shown to depend on both the material analyzed and the experimental conditions. A single detector efficiency factor is not recommended for each detector that would be used to correct routine sample analyses. An alternative three-run peak-shift sample analysis should be considered. A statistical analysis of the data from this peak-shift experiment can adjust the isotopic ratio estimates for detector differences due to each sample analysis.

  13. Field calibration of reference reflectance panels

    NASA Technical Reports Server (NTRS)

    Jackson, Ray D.; Moran, M. Susan; Slater, Philip N.; Biggar, Stuart F.

    1987-01-01

    A procedure for calibrating reference reflectance panels using the sun as the radiation source and a pressed-polytetrafluoroethylene powder standard is described. The directional/directional reflectance factor and the directional/hemispheric reflectance factor are examined. Directional/directional voltage responses for pressed-halon are analyzed. Three painted BaSO4 and one painted halon were calibrated using the proposed procedure. The effects of diffuse irradiance on reflectance-factor measurements are investigated. It is determined that the method has an accuracy on the order of 1 percent. The advantages and disadvantages of this method are discussed.

  14. TOF-SIMS: Accurate mass scale calibration

    Microsoft Academic Search

    F. M. Green; I. S. Gilmore; M. P. Seah

    2006-01-01

    A study is presented of the factors affecting the calibration of the mass scale in time-of-flight secondary ion mass spectrometry\\u000a (TOF-SIMS). At the present time, TOF-SIMS analysts using local calibration procedures achieve a rather poor relative mass\\u000a accuracy of only 150 ppm for large molecules (647 u) whereas for smaller fragments of <200 u this figure only improves to\\u000a 60

  15. On-Orbit Calibration of Satellite Gyroscopes

    NASA Technical Reports Server (NTRS)

    Hashmall, Joseph A.; Radomski, Mark; Sedlak, Joseph; Harman, Richard (Technical Monitor)

    2000-01-01

    In order to maneuver satellites accurately from one attitude to another, onboard rate sensing gyroscopes usually must be calibrated after launch. Several algorithms have been used to determine gyro biases, misalignments, and scale factors. This paper describes algorithms that have been used in the past, discusses their advantages and limitations, and describes a new algorithm and the gyro calibration results obtained using this new algorithm. The new algorithm has significant operational advantages in addition to being at least as accurate as other algorithms.

  16. Conditions for calibration of an isothermal titration calorimeter using chemical reactions.

    PubMed

    Sgarlata, Carmelo; Zito, Valeria; Arena, Giuseppe

    2013-01-01

    The reaction of protonation of 2-amino-2-(hydroxymethyl)-1,3-propanediol (TRIS) is a suitable one for the calibration of isothermal titration calorimeter (ITC), providing that experimental conditions are appropriately chosen. The conditions and methods for handling experimental data from a nanowatt-ITC are discussed. Also, the binding of Ba(2+) to 18-Crown-6 is successfully used to check the accuracy and precision of the chemical calibration performed with TRIS. This latter reaction has the additional advantage that the data can also be used for a check on the determination of the value of a binding constant. The anomaly of the first injection in ITC is analyzed and, by combining calorimetric and spectroscopic measurements, it is shown that it mainly results from a backlash effect of the syringe plunger rather than from a diffusion effect. PMID:23196751

  17. The development of GOSSYM calibration files for Texas cotton cultivars

    E-print Network

    Osborne, Dana Janell

    1989-01-01

    AND CONCLUSIONS PROPOSED FUTURE RESEARCH 52 55 TABI E OF CONTENTS (continued) REFERENCES APPENDIX A APPENDIX B APPENDIX C Page 58 60 79 91 VITA 101 LIST OF TABLES Table Page Example calibration file. 2a Description of calibration parameters 1...-10. . . 26 2b Description of calibration parameters 11-24. . 27 2c Description of calibration parameters 25-35. . 28 Classification of calibration factor effects on program parameters 29 Summary of comparison between file STRIP2 and Paymaster 404 field...

  18. RF impedance measurement calibration

    SciTech Connect

    Matthews, P.J.; Song, J.J.

    1993-02-12

    The intent of this note is not to explain all of the available calibration methods in detail. Instead, we will focus on the calibration methods of interest for RF impedance coupling measurements and attempt to explain: (1). The standards and measurements necessary for the various calibration techniques. (2). The advantages and disadvantages of each technique. (3). The mathematical manipulations that need to be applied to the measured standards and devices. (4). An outline of the steps needed for writing a calibration routine that operated from a remote computer. For further details of the various techniques presented in this note, the reader should consult the references.

  19. Metrology and Calibration Standards

    NSDL National Science Digital Library

    Equipment calibration issues are the name of the game here. Topics addressed range from "the adjustment dilemma" to terminology (for example "calibration" vs. "verification") to worldwide calibration standards. The site is sponsored by Agilent Technologies, a company that provides the semiconductor, electronics, communications, and related industries with testing solutions for test instruments, systems, equipment and monitoring tools. Users can be sure that every measurement is traceable to National Metrology Institutes (NMIs) through Agilent-engineered calibration procedures that verify instrument specifications. The site allows users to stay up-to-date on changing compliance requirements and their practical applications by working with Agilent meteorologists who collaborate with international standards organizations.

  20. Towards Automating Spacecraft Attitude Sensor Calibration

    NASA Technical Reports Server (NTRS)

    Sedlak, Joseph; Welter, Gary; Ottenstein, Neil

    2003-01-01

    With a view towards reducing cost and complexity for spacecraft early mission support at the NASA Goddard Space Flight Center (GSFC), efforts are being made to automate the attitude sensor calibration process. This paper addresses one of the major components needed by such a system. The beneficiaries of an improved calibration process are missions that demand moderate to high precision attitude knowledge or that need to perform accurate attitude slews. Improved slew accuracy reduces the time needed for re-acquisition of fine-pointing after each attitude maneuver, Rapid target acquisition can be very important for astronomical targeting or for off-nadir surface feature targeting by Earth-oriented spacecraft. The normal sequence of on-orbit calibration starts with alignment calibration of the star trackers and possibly the Sun sensor. Their relative alignment needs to be determined using a sufficiently large data set so their fields of view are adequately sampled. Next, the inertial reference unit (IRU) is calibrated for corrections to its alignment and scale factors. The IRU biases are estimated continuously by the onboard attitude control system, but the IRU alignment and scale factors are usually determined on the ground using a batch-processing method on a data set that includes several slews sufficient to give full observability of all the IRU calibration parameters. Finally, magnetometer biases, alignment, and its coupling to the magnetic torquers are determined in order io improve momentum management and occasionally for use in the attitude determination system. The detailed approach used for automating calibrations will depend on whether the automated system resides on the ground or on the spacecraft with an ultimate goal of autonomous calibration. Current efforts focus on a ground-based system driving subsystems that could run either on the ground or onboard. The distinction is that onboard calibration should process the data sequentially rather than in a single large batch since onboard computer data storage is limited. Very good batch- processing calibration utilities have been developed and used extensively at NASA/GSFC for mission support but no sequential calibration utilities are available. To meet this need, this paper presents the mathematical description of a sequential IRU calibration system. The system has been tested using flight data from the Rossi X-ray Timing Explorer (RXTE) during a series of attitude slews. The paper also discusses the current state of the overall automated system and describes plans for adding sequential alignment calibration and other additions that will reduce the amount of analyst time and input.

  1. Tissue-specific calibration of extracellular matrix material properties by transforming growth factor-? and Runx2 in bone is required for hearing.

    PubMed

    Chang, Jolie L; Brauer, Delia S; Johnson, Jacob; Chen, Carol G; Akil, Omar; Balooch, Guive; Humphrey, Mary Beth; Chin, Emily N; Porter, Alexandra E; Butcher, Kristin; Ritchie, Robert O; Schneider, Richard A; Lalwani, Anil; Derynck, Rik; Marshall, Grayson W; Marshall, Sally J; Lustig, Lawrence; Alliston, Tamara

    2010-10-01

    Physical cues, such as extracellular matrix stiffness, direct cell differentiation and support tissue-specific function. Perturbation of these cues underlies diverse pathologies, including osteoarthritis, cardiovascular disease and cancer. However, the molecular mechanisms that establish tissue-specific material properties and link them to healthy tissue function are unknown. We show that Runx2, a key lineage-specific transcription factor, regulates the material properties of bone matrix through the same transforming growth factor-? (TGF?)-responsive pathway that controls osteoblast differentiation. Deregulated TGF? or Runx2 function compromises the distinctly hard cochlear bone matrix and causes hearing loss, as seen in human cleidocranial dysplasia. In Runx2+/? mice, inhibition of TGF? signalling rescues both the material properties of the defective matrix, and hearing. This study elucidates the unknown cause of hearing loss in cleidocranial dysplasia, and demonstrates that a molecular pathway controlling cell differentiation also defines material properties of extracellular matrix. Furthermore, our results suggest that the careful regulation of these properties is essential for healthy tissue function. PMID:20847738

  2. Tissue-specific calibration of extracellular matrix material properties by transforming growth factor-? and Runx2 in bone is required for hearing

    PubMed Central

    Chang, Jolie L; Brauer, Delia S; Johnson, Jacob; Chen, Carol G; Akil, Omar; Balooch, Guive; Humphrey, Mary Beth; Chin, Emily N; Porter, Alexandra E; Butcher, Kristin; Ritchie, Robert O; Schneider, Richard A; Lalwani, Anil; Derynck, Rik; Marshall, Grayson W; Marshall, Sally J; Lustig, Lawrence; Alliston, Tamara

    2010-01-01

    Physical cues, such as extracellular matrix stiffness, direct cell differentiation and support tissue-specific function. Perturbation of these cues underlies diverse pathologies, including osteoarthritis, cardiovascular disease and cancer. However, the molecular mechanisms that establish tissue-specific material properties and link them to healthy tissue function are unknown. We show that Runx2, a key lineage-specific transcription factor, regulates the material properties of bone matrix through the same transforming growth factor-? (TGF?)-responsive pathway that controls osteoblast differentiation. Deregulated TGF? or Runx2 function compromises the distinctly hard cochlear bone matrix and causes hearing loss, as seen in human cleidocranial dysplasia. In Runx2+/? mice, inhibition of TGF? signalling rescues both the material properties of the defective matrix, and hearing. This study elucidates the unknown cause of hearing loss in cleidocranial dysplasia, and demonstrates that a molecular pathway controlling cell differentiation also defines material properties of extracellular matrix. Furthermore, our results suggest that the careful regulation of these properties is essential for healthy tissue function. PMID:20847738

  3. Factors

    NSDL National Science Digital Library

    2011-05-24

    This lesson is designed to develop students' abilities to find factors of whole numbers. The lesson also introduces prime numbers. This lesson provides links to discussions and activities related to factors as well as suggested ways to integrate them into the lesson. Finally, the lesson provides links to follow-up lessons designed for use in succession with the current one. Note, reading level is not indicated because the lesson does not include student reading material.

  4. Factoring

    NSDL National Science Digital Library

    Mrs. Taylor

    2010-10-19

    In this lesson we will explore prime numbers and factors A prime number has only two factors, 1 and itself. The Greek scholar, Eratosthenes of Cyrene lived from approximately 275 to 195 BC. He is know for being the first to have computed the size of the Earth and served as the director of the famous library in

  5. The use of anion-exchange disks in an optrode coupled to a multi-syringe flow-injection system for the determination and speciation analysis of iron in natural water samples.

    PubMed

    Pons, Carmen; Forteza, Rafael; Cerdà, Víctor

    2005-03-31

    A combination of multi-syringe flow-injection analysis (MSFIA) technique with an optical fibre reflectance sensor for the determination of iron in water samples has been developed in this work. Anion-exchange solid phase extraction (SPE) disks have been used as solid phase. Ammonium thiocyanate has been chosen as chromogenic reagent for Fe(III). The complex Fe[SCN](6)(3-) is retained onto the SPE disk and spectrophotometrically detected at 480nm. The complex is eluted with 0.25moll(-1) hydrochloric acid in 75% ethanol. Total iron can be determined by oxidising Fe(II) to Fe(III) with hydrogen peroxide. A mass calibration was run within the range of 0.4-37.5ng. The detection limit (3s(b)/S) was 0.4ng. The repeatability (RSD), calculated from 9 replicates using 0.5ml injections of a 25microgl(-1) concentration, was 3.6%. The repeatability between five anion-exchange disks was 5.4%. An injection throughput of 7 injections per hour for a sampling volume of 1ml has been achieved. The applicability of the proposed methodology in natural water samples has been proved. The properties of anion-exchange and chelating SPE disks have been studied and compared. PMID:18969983

  6. Cumulative sum quality control for calibrated breast density measurements

    SciTech Connect

    Heine, John J.; Cao Ke; Beam, Craig [Cancer Prevention and Control Division, Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, Florida 33612 (United States); Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, 1603 W. Taylor St., Chicago, Illinois 60612 (United States)

    2009-12-15

    Purpose: Breast density is a significant breast cancer risk factor. Although various methods are used to estimate breast density, there is no standard measurement for this important factor. The authors are developing a breast density standardization method for use in full field digital mammography (FFDM). The approach calibrates for interpatient acquisition technique differences. The calibration produces a normalized breast density pixel value scale. The method relies on first generating a baseline (BL) calibration dataset, which required extensive phantom imaging. Standardizing prospective mammograms with calibration data generated in the past could introduce unanticipated error in the standardized output if the calibration dataset is no longer valid. Methods: Sample points from the BL calibration dataset were imaged approximately biweekly over an extended timeframe. These serial samples were used to evaluate the BL dataset reproducibility and quantify the serial calibration accuracy. The cumulative sum (Cusum) quality control method was used to evaluate the serial sampling. Results: There is considerable drift in the serial sample points from the BL calibration dataset that is x-ray beam dependent. Systematic deviation from the BL dataset caused significant calibration errors. This system drift was not captured with routine system quality control measures. Cusum analysis indicated that the drift is a sign of system wear and eventual x-ray tube failure. Conclusions: The BL calibration dataset must be monitored and periodically updated, when necessary, to account for sustained system variations to maintain the calibration accuracy.

  7. Calibration facility safety plan

    NASA Technical Reports Server (NTRS)

    Fastie, W. G.

    1971-01-01

    A set of requirements is presented to insure the highest practical standard of safety for the Apollo 17 Calibration Facility in terms of identifying all critical or catastrophic type hazard areas. Plans for either counteracting or eliminating these areas are presented. All functional operations in calibrating the ultraviolet spectrometer and the testing of its components are described.

  8. Improved color image calibration

    Microsoft Academic Search

    Glenn A. Rogers; David J. Thomas

    1995-01-01

    The technique for calibrating color imagery which has been employed by the Tank-Automotive Research Development and Engineering Center (TARDEC) includes measurement of red, green, and blue color panels using a colorimeter during the approximate time that the calibration image is captured. This method has the advantage that the luminance and chromaticity coordinates of the color panels are recorded in real

  9. Improved Regression Calibration

    ERIC Educational Resources Information Center

    Skrondal, Anders; Kuha, Jouni

    2012-01-01

    The likelihood for generalized linear models with covariate measurement error cannot in general be expressed in closed form, which makes maximum likelihood estimation taxing. A popular alternative is regression calibration which is computationally efficient at the cost of inconsistent estimation. We propose an improved regression calibration

  10. Photogrammetric camera calibration

    USGS Publications Warehouse

    Tayman, W.P.; Ziemann, H.

    1984-01-01

    Section 2 (Calibration) of the document "Recommended Procedures for Calibrating Photogrammetric Cameras and Related Optical Tests" from the International Archives of Photogrammetry, Vol. XIII, Part 4, is reviewed in the light of recent practical work, and suggestions for changes are made. These suggestions are intended as a basis for a further discussion. ?? 1984.

  11. OLI Radiometric Calibration

    NASA Technical Reports Server (NTRS)

    Markham, Brian; Morfitt, Ron; Kvaran, Geir; Biggar, Stuart; Leisso, Nathan; Czapla-Myers, Jeff

    2011-01-01

    Goals: (1) Present an overview of the pre-launch radiance, reflectance & uniformity calibration of the Operational Land Imager (OLI) (1a) Transfer to orbit/heliostat (1b) Linearity (2) Discuss on-orbit plans for radiance, reflectance and uniformity calibration of the OLI

  12. POLARIMETRIC MICROWAVE RADIOMETER CALIBRATION

    E-print Network

    Sarabandi, Kamal

    POLARIMETRIC MICROWAVE RADIOMETER CALIBRATION by Jinzheng Peng A dissertation submitted in partial Radiometer 16 1.5 Error in the Measurement 22 1.6 Radiometer Calibration 31 1.7 Research Objectives and Dissertation Organization 37 IV #12;Chapter 2 Statistics of Radiometer Measurements 40 2.1 Noise Variance

  13. Revolving-Pinhole Calibrator

    NASA Technical Reports Server (NTRS)

    Hovenac, Edward A.

    1994-01-01

    Revolving-pinhole calibrator used to calibrate instrument called "Forward Scattering Spectrometer Probe" (FSSP). This instrument measures light scattered from water droplets in icing clouds. Scattering patterns used to determine sizes and distribution of sizes of droplets in connection with safety-oriented studies of icing on aircraft. Pinhole serves as diffraction standard for measuring small particles and drops.

  14. Calibration of sunphotometer for measurements of turbidity

    NASA Astrophysics Data System (ADS)

    Weihs, P.; Dirmhirn, I.; Czerwenka-Wenkstetten, I. M.

    1995-03-01

    This study investigates an alternative method to the Langley plot, a widely used but complex calibration method for sunphotometers. A sunphotometer has been calibrated using two different methods: the Langley method, a calibration to the extraterrestrial irradiance, and second by comparison to a standard instrument. The standard instrument used for these studies is spectrophotometer. The relative difference between the calibration factors obtained by the two methods is between 0.13% for the channel with the greatest sensitivity (500 nm) and 2% for the channel with the lowest signal (368 nm). The accuracy of both calibrations is of the same order of magnitude with relative errors between 1.2 and 7% for the Langley method and 2.9 to 5.3% for the standard instrument method. Analyses of the origin of possible errors show the sensitivity of the Langley method to less than ideal weather conditions, which could cause an error in calibration of up to 45% under extreme conditions and when too few measurements are made. This studies are made only for the UV and the visible range, investigations about the application of this technique in the near IR have still to be done and would also require spectrometers with a wider sensitivity range. These investigations do not alter the fact that frequent calibrations are still needed due to sensitivity changes like filter degradation.

  15. Calibration method for spectroscopic systems

    DOEpatents

    Sandison, D.R.

    1998-11-17

    Calibration spots of optically-characterized material placed in the field of view of a spectroscopic system allow calibration of the spectroscopic system. Response from the calibration spots is measured and used to calibrate for varying spectroscopic system operating parameters. The accurate calibration achieved allows quantitative spectroscopic analysis of responses taken at different times, different excitation conditions, and of different targets. 3 figs.

  16. Calibration method for spectroscopic systems

    DOEpatents

    Sandison, David R. (Edgewood, NM)

    1998-01-01

    Calibration spots of optically-characterized material placed in the field of view of a spectroscopic system allow calibration of the spectroscopic system. Response from the calibration spots is measured and used to calibrate for varying spectroscopic system operating parameters. The accurate calibration achieved allows quantitative spectroscopic analysis of responses taken at different times, different excitation conditions, and of different targets.

  17. Research on digital calibration method for optical surface defect dimension

    NASA Astrophysics Data System (ADS)

    Chen, Xiaoyu; Liu, Dong; Wang, Shitong; Cao, Pin; Gao, Xin; Yang, Yongying

    2012-10-01

    A digital calibration method for defect dimension of the optical surface is put forward to get the correspondence between the actual scale of defect on optical surface and the number of pixels of the defect image captured by CCD. Standard scratches, with their width ranging from 0.5?m to 40?m, are fabricated by electron beam exposure and reactive ion beam etching on two kinds of standard calibration board, quartz calibration board with and without chromium film. Calibration experiments are accomplished in five different microscope magnifications. Threshold segmentation, morphological operation and feature extraction are carried out in the images of calibration board to obtain the width of standard scratches in pixels. Interpret the theoretic trend of the calibration function as well as the linear range of it, and fit the calibration function based on the experimental results. According to the analysis and comparing of the calibration results in different microscope magnifications, error source and the factors limiting the resolving accuracy of the calibration system are analyzed. Ultimately, a standardization process including fabrication of the standard scratch, establishment of the standard calibration library for different microscope magnifications and the rapid calibration of actual detect is established. The calibration of the defects on the optical element in the size of 450mm× 450mm is successfully realized.

  18. GRAVITY: the calibration unit

    NASA Astrophysics Data System (ADS)

    Blind, N.; Eisenhauer, F.; Haug, M.; Gillessen, S.; Lippa, Magdalena; Burtscher, L.; Hans, O.; Haussmann, F.; Huber, S.; Janssen, A.; Kellner, S.; Kok, Y.; Ott, T.; Pfuhl, O.; Sturm, E.; Weber, J.; Wieprecht, E.; Amorim, A.; Brandner, W.; Perrin, G.; Perraut, K.; Straubmeier, C.

    2014-07-01

    We present in this paper the design and characterisation of a new sub-system of the VLTI 2nd generation instrument GRAVITY: the Calibration Unit. The Calibration Unit provides all functions to test and calibrate the beam combiner instrument: it creates two artificial stars on four beams, and dispose of four delay lines with an internal metrology. It also includes artificial stars for the tip-tilt and pupil guiding systems, as well as four metrology pick-up diodes, for tests and calibration of the corresponding sub-systems. The calibration unit also hosts the reference targets to align GRAVITY to the VLTI, and the safety shutters to avoid the metrology light to propagate in the VLTI-lab. We present the results of the characterisation and validtion of these differrent sub-units.

  19. Sandia WIPP calibration traceability

    SciTech Connect

    Schuhen, M.D. [Sandia National Labs., Albuquerque, NM (United States)] [Sandia National Labs., Albuquerque, NM (United States); Dean, T.A. [RE/SPEC, Inc., Albuquerque, NM (United States)] [RE/SPEC, Inc., Albuquerque, NM (United States)

    1996-05-01

    This report summarizes the work performed to establish calibration traceability for the instrumentation used by Sandia National Laboratories at the Waste Isolation Pilot Plant (WIPP) during testing from 1980-1985. Identifying the calibration traceability is an important part of establishing a pedigree for the data and is part of the qualification of existing data. In general, the requirement states that the calibration of Measuring and Test equipment must have a valid relationship to nationally recognized standards or the basis for the calibration must be documented. Sandia recognized that just establishing calibration traceability would not necessarily mean that all QA requirements were met during the certification of test instrumentation. To address this concern, the assessment was expanded to include various activities.

  20. A time and motion study of peripheral venous catheter flushing practice using manually prepared and prefilled flush syringes.

    PubMed

    Keogh, Samantha; Marsh, Nicole; Higgins, Niall; Davies, Karen; Rickard, Claire

    2014-01-01

    Peripheral venous catheters (PVCs) are the simplest and most frequently used method for drug, fluid, and blood product administration in the hospital setting. It is estimated that up to 90% of patients in acute care hospitals require a PVC; however, PVCs are associated with inherent complications, which can be mechanical or infectious. There have been a range of strategies to prevent or reduce PVC-related complications that include optimizing patency through the use of flushing. Little is known about the current status of flushing practice. This observational study quantified preparation and administration time and identified adherence to principles of Aseptic Non-Touch Technique and organizational protocol on PVC flushing by using both manually prepared and prefilled syringes. PMID:24583939

  1. The multiperson use of non-syringe injection equipment and risk of hepatitis c infection in a cohort of young adult injection drug users, chicago 1997–1999

    Microsoft Academic Search

    LE Thorpe; LJ Ouellet; RC Hershow; SL Bailey; ER Monerosso

    2000-01-01

    PURPOSE: The possibility that hepatitis C virus (HCV) is transmitted via the multiperson use of injection paraphernalia other than syringes has been suggested, but epidemiologic studies to examine the association are difficult to design due to saturation levels of infection in most samples of injection drug users (IDUs). This study (1) assembled a sample of young adult IDUs, among whom

  2. Implementation Study of Patient-Ready Syringes Containing 25?mg/mL Methotrexate Solution for Use in Treating Ectopic Pregnancy

    PubMed Central

    Respaud, R.; Gaudy, A. S.; Arlicot, C.; Tournamille, J. F.; Viaud-Massuard, M. C.; Elfakir, C.; Antier, D.

    2014-01-01

    Background. Ectopic pregnancy (EP) is a significant cause of morbidity and mortality during the first trimester of pregnancy. Small unruptured tubal pregnancies can be treated medically with a single dose of methotrexate (MTX). Objective. The aim of this study was to evaluate the stability of a 25?mg/mL solution of MTX to devise a secure delivery circuit for the preparation and use of this medication in the management of EP. Method. MTX solutions were packaged in polypropylene syringes, stored over an 84-day period, and protected from light either at +2 to +8°C or at 23°C. We assessed the physical and chemical stability of the solutions at various time points over the storage period. A pharmaceutical delivery circuit was implemented that involved the batch preparation of MTX syringes. Results. We show that 25?mg/mL MTX solutions remain stable over an 84-day period under the storage conditions tested. Standard doses were prepared, ranging from 50?mg to 100?mg. The results of this study suggest that MTX syringes can be prepared in advance by the pharmacy, ready to be dispensed at any time that a diagnosis of EP is made. Conclusion. The high stability of a 25?mg/mL MTX solution in polypropylene syringes makes it possible to implement a flexible and cost-effective delivery circuit for ready-to-use preparations of this drug, providing 24-hour access and preventing treatment delays. PMID:24900977

  3. Neighborhood differences in patterns of syringe access, use, and discard among injection drug users: implications for HIV outreach and prevention education.

    PubMed

    Buchanan, David; Shaw, Susan; Teng, Wei; Hiser, Poppy; Singer, Merrill

    2003-09-01

    The article presents results from the Syringe Access, Use, and Discard: Context in AIDS Risk research project comparing two neighborhoods by (1) socioeconomic and demographic characteristics; (2) patterns of syringe access, use, and discard; and (3) encounters with a local human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) outreach project targeted to injection drug users (IDUs). The results show that IDUs in more economically advantaged neighborhoods were more likely to acquire syringes from a single source (rather than multiple sources), more likely to inject alone in their own residence (rather than public injection locales), and more likely to dispose of syringes in private garbage cans rather alleys or dumpsters. These results are further associated with the likelihood of encountering street outreach workers, with IDUs in more affluent neighborhoods much less likely to have any such contacts. Based on the different patterns of access, use, and discard evident in each neighborhood, the results indicate that different and more carefully tailored local outreach and prevention strategies are urgently needed. PMID:12930882

  4. New technique for calibrating hydrocarbon gas flowmeters

    NASA Technical Reports Server (NTRS)

    Singh, J. J.; Puster, R. L.

    1984-01-01

    A technique for measuring calibration correction factors for hydrocarbon mass flowmeters is described. It is based on the Nernst theorem for matching the partial pressure of oxygen in the combustion products of the test hydrocarbon, burned in oxygen-enriched air, with that in normal air. It is applied to a widely used type of commercial thermal mass flowmeter for a number of hydrocarbons. The calibration correction factors measured using this technique are in good agreement with the values obtained by other independent procedures. The technique is successfully applied to the measurement of differences as low as one percent of the effective hydrocarbon content of the natural gas test samples.

  5. Identification of epidural space using loss of resistance syringe, infusion drip, and balloon technique: A comparative study

    PubMed Central

    Singhal, Suresh; Bala, Manju; Kaur, Kiranpreet

    2014-01-01

    Background and Objective: There are various techniques to identify epidural space but superiority of one technique over other has not been adequately studied. We conducted a study to Compare and evaluate the three techniques for epidural space localization that is, loss of resistance (LOR) syringe technique, balloon technique and drip infusion technique. Materials and Methods: Seventy-five patients of either sex, belonging to American Society of Anesthesiologists physical status Class 1 or 2, between 20 and 50 years of age, scheduled to undergo lower abdominal and lower limb surgeries were randomly allocated to one of the three groups (n = 25 each) depending upon epidural space localization. In Group I, epidural space localization was done with LOR syringe technique. In Group II Balloon technique and in Group III drip infusion technique was used. Distance of the epidural space from skin, number of attempts, time taken for epidural space localization and quality of the block were the parameter recorded during the study. Results: First attempt success rate for epidural space localization was highest in Group III (100%). The mean time taken for epidural space localization was least in Group III, and when compared with other groups it was found to be statistically significant with P = 0.016. Number of attempt for space localization and success rate of the block was better in the majority of patients of Group III, but the difference was found to be statistically nonsignificant. Complication rate was almost negligible in all three techniques. Conclusion: We conclude that the time taken to localize the epidural space was least in drip infusion technique. As for number of attempts, quality of the block and complications is concerned, all the three techniques are comparable. PMID:25538520

  6. Stability of Trisodium Citrate and Gentamicin Solution for Catheter Locks after Storage in Plastic Syringes at Room Temperature

    PubMed Central

    Cote, Dennis; Lok, Charmaine E; Battistella, Marisa; Vercaigne, Lavern

    2010-01-01

    Background: Catheter-related infections are a major problem for hemodialysis patients with central venous catheters for vascular access. Catheter lock solutions containing an anticoagulant are used to maintain the patency of the catheter between hemodialysis sessions. There is evidence that the use of lock solutions containing an antibiotic is associated with lower rates of infection but also that these solutions can kill microbes in colonized catheters and thus avoid the risks and costs associated with replacing the catheter. Objective: This stability study was conducted to determine whether an extemporaneously prepared gentamicin–citrate catheter lock solution would retain its potency over time, thus allowing for advance preparation of the solution. Methods: Catheter lock solutions containing gentamicin alone, citrate alone, and the combination of gentamicin and citrate were prepared aseptically and packaged in polyethylene syringes. The syringes were stored at room temperature. At timed intervals over 112 days, samples were withdrawn for analysis by means of validated high-performance liquid chromatography. Results: None of the 3 lock solutions showed any evidence of degradation during the 112-day observation period. In the formulation containing both gentamicin 2.5 mg/mL and sodium citrate 40 mg/mL (4%), there was no change in the concentration of either gentamicin (p = 0.34) or citrate (p = 0.55). Linear regression analysis of the concentration–time data for the combined formulation showed that 99.97% of the labelled amount of gentamicin and 101.30% of the labelled amount of citrate remained at day 112. The lower limit of the 95% confidence intervals indicated that more than 98.17% of the gentamicin and more than 99.57% of the citrate remained on day 112. Conclusion: The results of this study will allow pharmacies to extemporaneously compound the combined gentamicin–citrate catheter lock solution in advance of use. The method described here will yield a stable product for use in clinical applications. PMID:22478993

  7. Comparison of NovoPen 3 and syringes/vials in the acceptance of insulin therapy in NIDDM patients with secondary failure to oral hypoglycaemic agents.

    PubMed

    Kadiri, A; Chraibi, A; Marouan, F; Ababou, M R; el Guermai, N; Wadjinny, A; Kerfati, A; Douiri, M; Bensouda, J D; Belkhadir, J; Arvanitis, Y

    1998-07-01

    This open, randomised, cross-over study compared the acceptance and safety of NovoPen 3 with that of conventional syringes and vials when initiating insulin treatment in 96 NIDDM patients with secondary failure to oral hypoglycaemic agents. These patients had not previously been treated with insulin. All patients used each insulin administration system for 12 weeks. Group A started therapy using NovoPen 3 and crossed over to syringe/vial administration; Group B started with syringe/vial administration followed by NovoPen 3. In total, 78 patients completed the study. Most patients in Group A initially found the insulin injections very easy or easy and many of those who found injections easy at first found them very easy by the end of week 12. During the first period, patients in Group B found insulin administration more difficult than those in Group A. Injection pain was significantly lower with NovoPen 3 than with syringes and vials (P = 0.0018). Patients in Group B reported a significantly lower level of injection pain after the switch to using NovoPen 3 (P = 0.0003). Acceptance of insulin injections was significantly higher by patients using NovoPen 3 than by those using syringes and vials (P = 0.0059). Setting and drawing up the dose of insulin was also easier for patients using NovoPen 3 (P = 0.0490). At the end of the study, most patients (89.5% (68/76 replies)) said that they preferred NovoPen 3 to syringes and vials. Glycaemic control improved compared with baseline after starting insulin therapy, with no differences between Groups A and B, or between the two injection systems. The number of reported hypoglycaemic episodes was very low and was not significantly different between Groups A and B, or between the two administration systems. No treatment-related adverse events were reported. We conclude that use of NovoPen 3 provides better acceptance of insulin injection than use of conventional syringes and vials during initiation of insulin therapy in NIDDM patients with secondary failure to treatment with oral hypoglycaemic agents. PMID:9768368

  8. Link calibration against receiver calibration: an assessment of GPS time transfer uncertainties

    NASA Astrophysics Data System (ADS)

    Rovera, G. D.; Torre, J.-M.; Sherwood, R.; Abgrall, M.; Courde, C.; Laas-Bourez, M.; Uhrich, P.

    2014-10-01

    We present a direct comparison between two different techniques for the relative calibration of time transfer between remote time scales when using the signals transmitted by the Global Positioning System (GPS). Relative calibration estimates the delay of equipment or the delay of a time transfer link with respect to reference equipment. It is based on the circulation of some travelling GPS equipment between the stations in the network, against which the local equipment is measured. Two techniques can be considered: first a station calibration by the computation of the hardware delays of the local GPS equipment; second the computation of a global hardware delay offset for the time transfer between the reference points of two remote time scales. This last technique is called a ‘link’ calibration, with respect to the other one, which is a ‘receiver’ calibration. The two techniques require different measurements on site, which change the uncertainty budgets, and we discuss this and related issues. We report on one calibration campaign organized during Autumn 2013 between Observatoire de Paris (OP), Paris, France, Observatoire de la Côte d'Azur (OCA), Calern, France, and NERC Space Geodesy Facility (SGF), Herstmonceux, United Kingdom. The travelling equipment comprised two GPS receivers of different types, along with the required signal generator and distribution amplifier, and one time interval counter. We show the different ways to compute uncertainty budgets, leading to improvement factors of 1.2 to 1.5 on the hardware delay uncertainties when comparing the relative link calibration to the relative receiver calibration.

  9. COBE ground segment gyro calibration

    NASA Technical Reports Server (NTRS)

    Freedman, I.; Kumar, V. K.; Rae, A.; Venkataraman, R.; Patt, F. S.; Wright, E. L.

    1991-01-01

    Discussed here is the calibration of the scale factors and rate biases for the Cosmic Background Explorer (COBE) spacecraft gyroscopes, with the emphasis on the adaptation for COBE of an algorithm previously developed for the Solar Maximum Mission. Detailed choice of parameters, convergence, verification, and use of the algorithm in an environment where the reference attitudes are determined form the Sun, Earth, and star observations (via the Diffuse Infrared Background Experiment (DIRBE) are considered. Results of some recent experiments are given. These include tests where the gyro rate data are corrected for the effect of the gyro baseplate temperature on the spacecraft electronics.

  10. Airdata Measurement and Calibration

    NASA Technical Reports Server (NTRS)

    Haering, Edward A., Jr.

    1995-01-01

    This memorandum provides a brief introduction to airdata measurement and calibration. Readers will learn about typical test objectives, quantities to measure, and flight maneuvers and operations for calibration. The memorandum informs readers about tower-flyby, trailing cone, pacer, radar-tracking, and dynamic airdata calibration maneuvers. Readers will also begin to understand how some data analysis considerations and special airdata cases, including high-angle-of-attack flight, high-speed flight, and nonobtrusive sensors are handled. This memorandum is not intended to be all inclusive; this paper contains extensive reference and bibliography sections.

  11. DIRBE External Calibrator (DEC)

    NASA Technical Reports Server (NTRS)

    Wyatt, Clair L.; Thurgood, V. Alan; Allred, Glenn D.

    1987-01-01

    Under NASA Contract No. NAS5-28185, the Center for Space Engineering at Utah State University has produced a calibration instrument for the Diffuse Infrared Background Experiment (DIRBE). DIRBE is one of the instruments aboard the Cosmic Background Experiment Observatory (COBE). The calibration instrument is referred to as the DEC (Dirbe External Calibrator). DEC produces a steerable, infrared beam of controlled spectral content and intensity and with selectable point source or diffuse source characteristics, that can be directed into the DIRBE to map fields and determine response characteristics. This report discusses the design of the DEC instrument, its operation and characteristics, and provides an analysis of the systems capabilities and performance.

  12. Self-Calibration of Camera-Equipped Robot Manipulators

    Microsoft Academic Search

    Yan Meng; Hanqi Zhuang

    2001-01-01

    A new approach to self-calibrate a camera-equipped robot manip- ulator is proposed in this paper. Self-calibration here means that the camera-robot system is capable of determining its geometric parameters without any external measurements and\\/or ground truth calibration data. With the proposed approach, one is able to identify all the rotational parameters and, up to a scale factor, all the trans-

  13. Calibration of the STAR Forward Time Projection Chamber with Krypton-83m

    E-print Network

    V. Eckardt; T. Eggert; H. Fessler; H. Hümmler; G. Lo Curto; M. Oldenburg; N. Schmitz; A. Schüttauf; J. Seyboth; P. Seyboth; M. Vidal

    2001-01-31

    The principles of the calibration of a time projection chamber with radioactive Krypton-83 are explained. The calculation of gain correction factors and the methods of obtaining a precise energy calibration are illustrated. The properties and advantages of \

  14. The ISOCAM Strategy for In-flight Calibration

    NASA Astrophysics Data System (ADS)

    Metcalfe, L.

    Many factors combined in order to form the ISOCAM in-flight calibration strategy : (a) the history of the mission development and the evolution of the ground segment design; (b) the approach to planning and organising the work of the Instrument Dedicated Team (IDT) and the tools available to do the work; (c) the preparation of the in-flight calibration command sequences, including the approach to pre-flight testing and simulation of the sequences (distinct from the mainline instrument ground calibration and characterisation); (d) the distribution in time of the calibration observations and any need for special calibration periods; (e) serendipitous calibration: including calibrations extracted from routine science observations or achieved opportunistically through benefiting from regularly scheduled spacecraft or orbital maintenance periods; (f) the amount of time we really needed to accomplish a good calibration vs. the time we had. Could we have performed ALL calibration in-flight? (g) the choice of which Uplink System to use and when (CUS or AOTs); (h) the value and role of formal procedures vs. personal checklists, training and experience; (i) the usage and value of different categories of documentation and the avoidance of extraneous documentation and useless effort; (j) how did the calibrators interface with the rest of the system. These issues will be discussed as a prelude to the more detailed presentations on specific aspects of the calibration which will follow during the course of the meeting.

  15. Roundness calibration standard

    DOEpatents

    Burrus, Brice M. (6620 Wachese La., Knoxville, TN 37912)

    1984-01-01

    A roundness calibration standard is provided with a first arc constituting the major portion of a circle and a second arc lying between the remainder of the circle and the chord extending between the ends of said first arc.

  16. Calibrating Radiocarbon Ages

    NSDL National Science Digital Library

    Calibrating Radiocarbon Ages This activity was developed during the Teaching Climate Change from the Geological Record workshop, held in August 2010.Contributed by Eric Grimm, Jared Beeton, and Mark Skidmore. ...

  17. Calibrating the Younger Dryas

    NSDL National Science Digital Library

    Calibrating the Younger Dryas Contributed by: Thom Davis, Greg Wiles, Roger Brown, David Bary This activity was developed during the Teaching Climate Change from the Geological Record workshop, held in August ...

  18. Calibrating skinfold calipers.

    PubMed

    Gore, C J; Woolford, S M; Carlyon, R G

    1995-08-01

    While athletes are routinely assessed for changes in subcutaneous adipose tissue with skinfold calipers, absolute dynamic calibration of caliper jaw compression is currently not possible. The first part of this study describes how dynamic compression of foam rubber blocks can be used to monitor the relative calibration of a single pair of calipers as springs fatigue, or to alert an investigator to variations in measurement values between different calipers. The second part of the study, carried out on 10 female athletes, demonstrated that the significant differences established by the foam block method of calibration also translated into a significant difference for the sum of seven subcutaneous skinfolds. Foam blocks can be used as a simple, inexpensive method to establish a calibration range and can also be used to recheck calipers periodically, depending upon their use. PMID:7474049

  19. Gauge calibration by diffusion

    NASA Technical Reports Server (NTRS)

    Brock, F. J.; Feakes, F. (inventors)

    1968-01-01

    Vacuum gage calibration by diffusing a known quantity of gas through a heated barrier into a gauge is examined. The gas flow raises the pressure in the gauge to known level and is then compared with the gauge's pressure reading.

  20. Calibrated Properties Model

    SciTech Connect

    C. Ahlers; H. Liu

    2000-03-12

    The purpose of this Analysis/Model Report (AMR) is to document the Calibrated Properties Model that provides calibrated parameter sets for unsaturated zone (UZ) flow and transport process models for the Yucca Mountain Site Characterization Project (YMP). This work was performed in accordance with the ''AMR Development Plan for U0035 Calibrated Properties Model REV00. These calibrated property sets include matrix and fracture parameters for the UZ Flow and Transport Model (UZ Model), drift seepage models, drift-scale and mountain-scale coupled-processes models, and Total System Performance Assessment (TSPA) models as well as Performance Assessment (PA) and other participating national laboratories and government agencies. These process models provide the necessary framework to test conceptual hypotheses of flow and transport at different scales and predict flow and transport behavior under a variety of climatic and thermal-loading conditions.

  1. Precision biological rate calibrator

    Microsoft Academic Search

    A. J. Cousin

    1978-01-01

    A circuit design for a precison rate calibrator intended for biological use is discussed in detail. Although the simulator\\u000a is quite general in nature, an e.c.g. output stage is designed as an example of its use in calibrating a cardiotachometer.\\u000a Rates available range from 1 beat\\/min to 999 beats\\/min in 1 beat\\/min increments. It is a battery-powered low-cost unit.

  2. Integrated calibration sphere and calibration step fixture for improved coordinate measurement machine calibration

    DOEpatents

    Clifford, Harry J. (Los Alamos, NM)

    2011-03-22

    A method and apparatus for mounting a calibration sphere to a calibration fixture for Coordinate Measurement Machine (CMM) calibration and qualification is described, decreasing the time required for such qualification, thus allowing the CMM to be used more productively. A number of embodiments are disclosed that allow for new and retrofit manufacture to perform as integrated calibration sphere and calibration fixture devices. This invention renders unnecessary the removal of a calibration sphere prior to CMM measurement of calibration features on calibration fixtures, thereby greatly reducing the time spent qualifying a CMM.

  3. Absolute Calibration and Characterization of the Multiband Imaging Photometer for Spitzer. I. The Stellar Calibrator Sample and the 24 micron Calibration

    E-print Network

    C. W. Engelbracht; M. Blaylock; K. Y. L. Su; J. Rho; G. H. Rieke; J. Muzerolle; D. L. Padgett; D. C. Hines; K. D. Gordon; D. Fadda; A. Noriega-Crespo; D. M. Kelly; W. B. Latter; J. L. Hinz; K. A. Misselt; J. E. Morrison; J. A. Stansberry; D. L. Shupe; S. Stolovy; Wm. A. Wheaton; E. T. Young; G. Neugebauer; S. Wachter; P. G. Pérez-González; D. T. Frayer; F. R. Marleau

    2007-04-17

    We present the stellar calibrator sample and the conversion from instrumental to physical units for the 24 micron channel of the Multiband Imaging Photometer for Spitzer (MIPS). The primary calibrators are A stars, and the calibration factor based on those stars is 4.54*10^{-2} MJy sr^{-1} (DN/s)^{-1}, with a nominal uncertainty of 2%. We discuss the data-reduction procedures required to attain this accuracy; without these procdures, the calibration factor obtained using the automated pipeline at the Spitzer Science Center is 1.6% +/- 0.6% lower. We extend this work to predict 24 micron flux densities for a sample of 238 stars which covers a larger range of flux densities and spectral types. We present a total of 348 measurements of 141 stars at 24 micron. This sample covers a factor of ~460 in 24 micron flux density, from 8.6 mJy up to 4.0 Jy. We show that the calibration is linear over that range with respect to target flux and background level. The calibration is based on observations made using 3-second exposures; a preliminary analysis shows that the calibration factor may be 1% and 2% lower for 10- and 30-second exposures, respectively. We also demonstrate that the calibration is very stable: over the course of the mission, repeated measurements of our routine calibrator, HD 159330, show a root-mean-square scatter of only 0.4%. Finally, we show that the point spread function (PSF) is well measured and allows us to calibrate extended sources accurately; Infrared Astronomy Satellite (IRAS) and MIPS measurements of a sample of nearby galaxies are identical within the uncertainties.

  4. Self-consistent algorithm for calibrating spectrometers to picometer accuracy over the entire wavelength range.

    PubMed

    Perret, Edith; Balmer, Tobias E; Heuberger, Manfred

    2010-10-01

    Spectrometer calibration accuracies are of high importance for a wide range of applications. Typically, one calibrates the spectrometer with a calibration lamp, providing distinct and well-defined calibration lines. However, for small spectral ranges, where only two calibration lines are present, the calibration becomes inaccurate. We present a high-precision nonlinear wavelength calibration method, which is based on two or more reference lines from a calibration lamp. The additional key element introduced is a Fabry-Perot multilayer structure that yields multiple sharp transmission maxima of similar intensity over the full spectrometer range under broad-band illumination (e.g., white-light source). An iterative algorithm is put forward to obtain a self-consistent calibration of picometer precision over the full spectrometer range. In regions distant from calibration lines the accuracy is enhanced by at least a factor of two compared to conventional methods. PMID:20925984

  5. A miniature remote deadweight calibrator

    NASA Technical Reports Server (NTRS)

    Supplee, Frank H., Jr.; Tcheng, Ping

    1986-01-01

    A miniature, computer-controlled, deadweight calibrator was developed to remotely calibrate a force transducer mounted in a cryogenic chamber. This simple mechanism allows automatic loading and unloading of deadweights placed onto a skin friction balance during calibrations. Equipment for the calibrator includes a specially designed set of five interlocking 200-milligram weights, a motorized lifting platform, and a controller box taking commands from a microcomputer on an IEEE interface. The computer is also used to record and reduce the calibration data and control other calibration parameters. The full-scale load for this device is 1,000 milligrams; however, the concept can be extended to accommodate other calibration ranges.

  6. Unexplored Indoors method for pyranometers calibration traceable to SI

    NASA Astrophysics Data System (ADS)

    Castillo-Matadamas, H. A.; Molina-Vazquez, J. C.; Quintero-Torres, R.

    2015-01-01

    A method to calibrate pyranometers with direct traceability to the International System of Units (SI) is presented, the method use an electrically calibrated pyroelectric detector (ECPR) as standard and offers numerous advantages over outdoors conventional calibration methods, such as reducing the uncertainty from the reference standard and the final uncertainty of the sensitivity coefficient of the calibrated pyranometer; the measurement uncertainty achieved with this method at normal irradiance is 2.1% for a coverage factor k = 2 and could be reduce if one reduces the uncertainty level of the reference standard.

  7. Calibration Under Uncertainty.

    SciTech Connect

    Swiler, Laura Painton; Trucano, Timothy Guy

    2005-03-01

    This report is a white paper summarizing the literature and different approaches to the problem of calibrating computer model parameters in the face of model uncertainty. Model calibration is often formulated as finding the parameters that minimize the squared difference between the model-computed data (the predicted data) and the actual experimental data. This approach does not allow for explicit treatment of uncertainty or error in the model itself: the model is considered the %22true%22 deterministic representation of reality. While this approach does have utility, it is far from an accurate mathematical treatment of the true model calibration problem in which both the computed data and experimental data have error bars. This year, we examined methods to perform calibration accounting for the error in both the computer model and the data, as well as improving our understanding of its meaning for model predictability. We call this approach Calibration under Uncertainty (CUU). This talk presents our current thinking on CUU. We outline some current approaches in the literature, and discuss the Bayesian approach to CUU in detail.

  8. Psychophysical contrast calibration

    PubMed Central

    To, Long; Woods, Russell L; Goldstein, Robert B; Peli, Eli

    2013-01-01

    Electronic displays and computer systems offer numerous advantages for clinical vision testing. Laboratory and clinical measurements of various functions and in particular of (letter) contrast sensitivity require accurately calibrated display contrast. In the laboratory this is achieved using expensive light meters. We developed and evaluated a novel method that uses only psychophysical responses of a person with normal vision to calibrate the luminance contrast of displays for experimental and clinical applications. Our method combines psychophysical techniques (1) for detection (and thus elimination or reduction) of display saturating nonlinearities; (2) for luminance (gamma function) estimation and linearization without use of a photometer; and (3) to measure without a photometer the luminance ratios of the display’s three color channels that are used in a bit-stealing procedure to expand the luminance resolution of the display. Using a photometer we verified that the calibration achieved with this procedure is accurate for both LCD and CRT displays enabling testing of letter contrast sensitivity to 0.5%. Our visual calibration procedure enables clinical, internet and home implementation and calibration verification of electronic contrast testing. PMID:23643843

  9. Hydrometer calibration by hydrostatic weighing with automated liquid surface positioning

    NASA Astrophysics Data System (ADS)

    Aguilera, Jesus; Wright, John D.; Bean, Vern E.

    2008-01-01

    We describe an automated apparatus for calibrating hydrometers by hydrostatic weighing (Cuckow's method) in tridecane, a liquid of known, stable density, and with a relatively low surface tension and contact angle against glass. The apparatus uses a laser light sheet and a laser power meter to position the tridecane surface at the hydrometer scale mark to be calibrated with an uncertainty of 0.08 mm. The calibration results have an expanded uncertainty (with a coverage factor of 2) of 100 parts in 106 or less of the liquid density. We validated the apparatus by comparisons using water, toluene, tridecane and trichloroethylene, and found agreement within 40 parts in 106 or less. The new calibration method is consistent with earlier, manual calibrations performed by NIST. When customers use calibrated hydrometers, they may encounter uncertainties of 370 parts in 106 or larger due to surface tension, contact angle and temperature effects.

  10. Photometric Calibration of the Swift Ultraviolet/Optical Telescope

    E-print Network

    T. S. Poole; A. A. Breeveld; M. J. Page; W. Landsman; S. T. Holland; P. Roming; N. P. M. Kuin; P. J. Brown; C. Gronwall; S. Hunsberger; S. Koch; K. O. Mason; P. Schady; D. Vanden Berk; A. J. Blustin; P. Boyd; P. Broos; M. Carter; M. M. Chester; A. Cucchiara; B. Hancock; H. Huckle; S. Immler; M. Ivanushkina; T. Kennedy; F. Marshall; A. Morgan; S. Pandey; M. de Pasquale; P. J. Smith; M. Still

    2007-11-09

    We present the photometric calibration of the Swift UltraViolet/Optical Telescope (UVOT) which includes: optimum photometric and background apertures, effective area curves, colour transformations, conversion factors for count rates to flux, and the photometric zero points (which are accurate to better than 4 per cent) for each of the seven UVOT broadband filters. The calibration was performed with observations of standard stars and standard star fields that represent a wide range of spectral star types. The calibration results include the position dependent uniformity, and instrument response over the 1600-8000A operational range. Because the UVOT is a photon counting instrument, we also discuss the effect of coincidence loss on the calibration results. We provide practical guidelines for using the calibration in UVOT data analysis. The results presented here supersede previous calibration results.

  11. A Comparison of Two Balance Calibration Model Building Methods

    NASA Technical Reports Server (NTRS)

    DeLoach, Richard; Ulbrich, Norbert

    2007-01-01

    Simulated strain-gage balance calibration data is used to compare the accuracy of two balance calibration model building methods for different noise environments and calibration experiment designs. The first building method obtains a math model for the analysis of balance calibration data after applying a candidate math model search algorithm to the calibration data set. The second building method uses stepwise regression analysis in order to construct a model for the analysis. Four balance calibration data sets were simulated in order to compare the accuracy of the two math model building methods. The simulated data sets were prepared using the traditional One Factor At a Time (OFAT) technique and the Modern Design of Experiments (MDOE) approach. Random and systematic errors were introduced in the simulated calibration data sets in order to study their influence on the math model building methods. Residuals of the fitted calibration responses and other statistical metrics were compared in order to evaluate the calibration models developed with different combinations of noise environment, experiment design, and model building method. Overall, predicted math models and residuals of both math model building methods show very good agreement. Significant differences in model quality were attributable to noise environment, experiment design, and their interaction. Generally, the addition of systematic error significantly degraded the quality of calibration models developed from OFAT data by either method, but MDOE experiment designs were more robust with respect to the introduction of a systematic component of the unexplained variance.

  12. Calibration Systems Final Report

    SciTech Connect

    Myers, Tanya L.; Broocks, Bryan T.; Phillips, Mark C.

    2006-02-01

    The Calibration Systems project at Pacific Northwest National Laboratory (PNNL) is aimed towards developing and demonstrating compact Quantum Cascade (QC) laser-based calibration systems for infrared imaging systems. These on-board systems will improve the calibration technology for passive sensors, which enable stand-off detection for the proliferation or use of weapons of mass destruction, by replacing on-board blackbodies with QC laser-based systems. This alternative technology can minimize the impact on instrument size and weight while improving the quality of instruments for a variety of missions. The potential of replacing flight blackbodies is made feasible by the high output, stability, and repeatability of the QC laser spectral radiance.

  13. In situ hydrodynamic lateral force calibration of AFM colloidal probes.

    PubMed

    Ryu, Sangjin; Franck, Christian

    2011-11-01

    Lateral force microscopy (LFM) is an application of atomic force microscopy (AFM) to sense lateral forces applied to the AFM probe tip. Recent advances in tissue engineering and functional biomaterials have shown a need for the surface characterization of their material and biochemical properties under the application of lateral forces. LFM equipped with colloidal probes of well-defined tip geometries has been a natural fit to address these needs but has remained limited to provide primarily qualitative results. For quantitative measurements, LFM requires the successful determination of the lateral force or torque conversion factor of the probe. Usually, force calibration results obtained in air are used for force measurements in liquids, but refractive index differences between air and liquids induce changes in the conversion factor. Furthermore, in the case of biochemically functionalized tips, damage can occur during calibration because tip-surface contact is inevitable in most calibration methods. Therefore, a nondestructive in situ lateral force calibration is desirable for LFM applications in liquids. Here we present an in situ hydrodynamic lateral force calibration method for AFM colloidal probes. In this method, the laterally scanned substrate surface generated a creeping Couette flow, which deformed the probe under torsion. The spherical geometry of the tip enabled the calculation of tip drag forces, and the lateral torque conversion factor was calibrated from the lateral voltage change and estimated torque. Comparisons with lateral force calibrations performed in air show that the hydrodynamic lateral force calibration method enables quantitative lateral force measurements in liquid using colloidal probes. PMID:21905684

  14. Calibrating pressure sensitive paints using proper orthogonal decomposition

    NASA Astrophysics Data System (ADS)

    Omar, Ahmed F.

    Pressure sensitive paints (PSP) have been gaining more popularity in experimental fluid mechanics and aerodynamic testing. A major problem with PSP pertains to its temperature dependence making the calibration process very difficult. Dual-luminophor PSP has an added temperature phosphor to provide temperature information for the calibration. Dual-luminophor systems still suffer from the inherent temperature dependence and possess added complications due to spectral cross talk and overlap. However, to date there is no successful universal calibration technique for dual-luminophor systems. Such calibration is needed for dual-luminophor PSP to become a practical experimental tool. With this aim, a statistical technique known as proper orthogonal decomposition (POD) is used to extract pressure and temperature information from intensity data. POD works by defining and separating the main factors of any system and evaluating the proportional contribution of each factor. The calibration technique is examined by applying the dual-luminophor PSP in a channel flow experiment. Before applying the calibration experimentally, a set of artificial data is examined using POD to provide a fundamental understanding of POD as a calibration technique. The experiment was designed to allow for different flow conditions and temperature gradients to interact, hence providing enough variation to examine the calibration technique. Seven cases are examined, with each case shedding light on a particular aspect of the calibration. The POD calibration is compared to the intensity-ratio calibration in order to emphasize the effectiveness of the technique. Finally, results are evaluated for accuracy and a detailed uncertainty analysis is performed to fully assess the POD calibration.

  15. 40 CFR 91.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...of a single calibration factor for that range. If the deviation exceeds two percent at any point, use the best-fit non-linear equation which represents the data to within two percent of each test point to determine...

  16. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...of a single calibration factor for that range. If the deviation exceeds two percent at any point, use the best-fit non-linear equation which represents the data to within two percent of each test point to determine...

  17. 40 CFR 91.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...of a single calibration factor for that range. If the deviation exceeds two percent at any point, use the best-fit non-linear equation which represents the data to within two percent of each test point to determine...

  18. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...of a single calibration factor for that range. If the deviation exceeds two percent at any point, use the best-fit non-linear equation which represents the data to within two percent of each test point to determine...

  19. 40 CFR 91.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...of a single calibration factor for that range. If the deviation exceeds two percent at any point, use the best-fit non-linear equation which represents the data to within two percent of each test point to determine...

  20. 40 CFR 90.317 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...of a single calibration factor for that range. If the deviation exceeds two percent at any point, use the best-fit non-linear equation which represents the data to within two percent of each test point to determine...

  1. INS-Camera Calibration without Ground Control Points

    E-print Network

    Cremers, Daniel

    factor six compared to a terrestrial calibration. I. INTRODUCTION Aerial photogrammetry is widely used for orthophoto and digital terrain model creation. Nowadays these measuring flights are usually performed with real-world data from sensors mounted on an aerial v

  2. Dual-syringe reactive electrospinning of cross-linked hyaluronic acid hydrogel nanofibers for tissue engineering applications.

    PubMed

    Ji, Yuan; Ghosh, Kaustabh; Li, Bingquan; Sokolov, Jonathan C; Clark, Richard A F; Rafailovich, Miriam H

    2006-10-20

    A facile fabrication of a cross-linked hyaluronic acid (HA) hydrogel nanofibers by a reactive electrospinning method is described. A thiolated HA derivative, 3,3'-dithiobis(propanoic dihydrazide)-modified HA (HA-DTPH), and poly(ethylene glycol) diacrylate (PEGDA) are selected as the cross-linking system. The cross-linking reaction occurs simultaneously during the electrospinning process using a dual-syringe mixing technique. Poly(ethylene oxide) (PEO) is added into the spinning solution as a viscosity modifier to facilitate the fiber formation and is selectively removed with water after the electrospinning process. The nanofibrous structure of the electrospun HA scaffold is well preserved after hydration with an average fiber diameter of 110 nm. A cell morphology study on fibronectin (FN)-adsorbed HA nanofibrous scaffolds shows that the NIH 3T3 fibroblasts migrate into the scaffold through the nanofibrous network, and demonstrate an elaborate three-dimensional dendritic morphology within the scaffold, which reflects the dimensions of the electrospun HA nanofibers. These results suggest the application of electrospun HA nanofibrous scaffolds as a potential material for wound healing and tissue regeneration. [image: see text] Laser scanning confocal microscopy demonstrates that the NIH3T3 fibroblast develops an extended 3D dendritic morphology within the fibronectin-adsorbed electrospun HA nanofibrous scaffold. PMID:17022092

  3. Life After the Ban: An Assessment of US Syringe Exchange Programs’ Attitudes About and Early Experiences With Federal Funding

    PubMed Central

    Martin, Erika G.; Bowman, Sarah E.; Mann, Marita R.; Beletsky, Leo

    2012-01-01

    Objectives. We aimed to determine whether syringe exchange programs (SEPs) currently receive or anticipate pursuing federal funding and barriers to funding applications following the recent removal of the long-standing ban on using federal funds for SEPs. Methods. We conducted a telephone-administered cross-sectional survey of US SEPs. Descriptive statistics summarized responses; bivariate analyses examined differences in pursuing funding and experiencing barriers by program characteristics. Results. Of the 187 SEPs (92.1%) that responded, 90.9% were legally authorized. Three received federal funds and 116 intended to pursue federal funding. Perceived federal funding barriers were common and included availability and accessibility of funds, legal requirements such as written police support, resource capacity to apply and comply with funding regulations, local political and structural organization, and concern around altering program culture. Programs without legal authorization, health department affiliation, large distribution, or comprehensive planning reported more federal funding barriers. Conclusions. Policy implementation gaps appear to render federal support primarily symbolic. In practice, funding opportunities may not be available to all SEPs. Increased technical assistance and legal reform could improve access to federal funds, especially for SEPs with smaller capacity and tenuous local support. PMID:22420810

  4. Simplicity, safety, and acceptability of insulin pen use versus the conventional vial/syringe device in patients with type 1 and type 2 diabetes mellitus in Lebanon

    PubMed Central

    Ramadan, Wijdan H; Khreis, Noura A; Kabbara, Wissam K

    2015-01-01

    Background The aim of the study was to evaluate the simplicity, safety, patients’ preference, and convenience of the administration of insulin using the pen device versus the conventional vial/syringe in patients with diabetes. Methods This observational study was conducted in multiple community pharmacies in Lebanon. The investigators interviewed patients with diabetes using an insulin pen or conventional vial/syringe. A total of 74 questionnaires were filled over a period of 6 months. Answers were entered into the Statistical Package for Social Sciences (SPSS) software and Excel spreadsheet. t-test, logistic regression analysis, and correlation analysis were used in order to analyze the results. Results A higher percentage of patients from the insulin pen users group (95.2%) found the method easy to use as compared to only 46.7% of the insulin conventional users group (P 0.001, relative risk [RR]: 2.041, 95% confidence interval [CI]: 1.178–3.535). Moreover, 61.9% and 26.7% of pen users and conventional users, respectively, could read the scale easily (P 0.037, RR 2.321, 95% CI: 0.940–5.731), while 85.7% of pen users found it more convenient shifting to pen and 86.7% of the conventional users would want to shift to pen if it had the same cost. Pain perception was statistically different between the groups. A much higher percentage (76.2%) of pen users showed no pain during injection compared to only 26.7% of conventional users (P 0.003, RR 2.857, 95% CI: 1.194–6.838). Conclusion The insulin pen was significantly much easier to use and less painful than the conventional vial/syringe. Proper education on the methods of administration/storage and disposal of needles/syringes is needed in both groups.

  5. Determination of ammonium in aqueous samples using new headspace dynamic in-syringe liquid-phase microextraction with in situ derivitazation coupled with liquid chromatography-fluorescence detection.

    PubMed

    Muniraj, Sarangapani; Yan, Cheing-Tong; Shih, Hou-Kung; Ponnusamy, Vinoth Kumar; Jen, Jen-Fon

    2012-11-19

    A new simultaneous derivatization and extraction method for the preconcentration of ammonia using new one-step headspace dynamic in-syringe liquid-phase microextraction with in situ derivatization was developed for the trace determination of ammonium in aqueous samples by liquid chromatography with fluorescence detection (LC-FLD). The acceptor phase (as derivatization reagent) containing o-phthaldehyde and sodium sulfite was held within a syringe barrel and immersed in the headspace of sample container. The gaseous ammonia from the alkalized aqueous sample formed a stable isoindole derivative with the acceptor phase inside the syringe barrel through the reciprocated movements of plunger. After derivatization-cum-extraction, the acceptor phase was directly injected into LC-FLD for analysis. Parameters affecting the ammonia evolution and the extraction/derivatization efficiency such as sample matrix, pH, temperature, sampling time, and the composition of derivatization reagent, reaction temperature, and frequency of reciprocated plunger, were studied thoroughly. Results indicated that the maximum extraction efficiency was obtained by using 100?L derivatization reagent in a 1-mL gastight syringe under 8 reciprocated movements of plunger per min to extract ammonia evolved from a 20mL alkalized aqueous solution at 70°C (preheated 4min) with 380rpm stirring for 8min. The detection was linear in the concentration range of 0.625-10?M with the correlation coefficient of 0.9967 and detection limit of 0.33?M (5.6ng mL(-1)) based on SN(-1)=3. The method was applied successfully to determine ammonium in real water samples without any prior cleanup of the samples, and has been proved to be a simple, sensitive, efficient and cost-effective procedure for trace ammonium determination in aqueous samples. PMID:23140954

  6. Autonomous Phase Retrieval Calibration

    NASA Technical Reports Server (NTRS)

    Estlin, Tara A.; Chien, Steve A.; Castano, Rebecca; Gaines, Daniel M.; Doubleday, Joshua R.; Schoolcraft, Josua B.; Oyake, Amalaye; Vaughs, Ashton G.; Torgerson, Jordan L.

    2011-01-01

    The Palomar Adaptive Optics System actively corrects for changing aberrations in light due to atmospheric turbulence. However, the underlying internal static error is unknown and uncorrected by this process. The dedicated wavefront sensor device necessarily lies along a different path than the science camera, and, therefore, doesn't measure the true errors along the path leading to the final detected imagery. This is a standard problem in adaptive optics (AO) called "non-common path error." The Autonomous Phase Retrieval Calibration (APRC) software suite performs automated sensing and correction iterations to calibrate the Palomar AO system to levels that were previously unreachable.

  7. Laboratory radiometric calibration for the convex grating imaging spectrometer

    NASA Astrophysics Data System (ADS)

    Zhou, Jiankang; Chen, Xinhua; Chen, Yuheng; Ji, Yiqun; Shen, Weimin

    2014-09-01

    The radiometric calibration of imaging spectrometer plays an import role for scientific application of spectral data. The radiometric calibration accuracy is influenced by many factors, such as the stability and uniformity of light source, the transfer precision of radiation standard and so on. But the deviation from the linear response mode and the polarization effect of the imaging spectrometer are always neglected. In this paper, the linear radiometric calibration model is constructed and the radiometric linear response capacity is test by adjusting electric gain, exposure time and radiance level. The linear polarizer and the sine function fitting algorithm are utilized to measure polarization effect. The integrating sphere calibration system is constructed in our Lab and its spectral radiance is calibrated by a well-characterized and extremely stable NIST traceable transfer spectroradiometer. Our manufactured convex grating imaging spectrometer is relative and absolute calibrated based on the integrating sphere calibration system. The relative radiometric calibration data is used to remove or reduce the radiometric response non-uniformity every pixel of imaging spectrometer while the absolute radiometric calibration is used to construct the relationship between the physical radiant of the scene and the digital number of the image. The calibration coefficients are acquired at ten radiance levels. The diffraction noise in the images can be corrected by the calibration coefficients and the uniform radiance image can be got. The calibration result shows that our manufactured imaging spectrometer with convex grating has 3.0% degree of polarization and the uncertainties of the relative and absolute radiometric calibrations are 2.4% and 5.6% respectively.

  8. Calibrating transport lines using LOCO techniques

    SciTech Connect

    Yves Roblin

    2011-09-01

    With the 12GeV upgrade underway at CEBAF, there is a need to re-characterize the beamlines after the modifications made to it to accommodate running at higher energies. We present a linear perturbation approach to calibrating the optics model of transport lines. This method is adapted from the LOCO method in use for storage rings. We consider the effect of quadrupole errors, dipole construction errors as well as beam position monitors and correctors calibrations. The ideal model is expanded to first order in Taylor series of the quadrupole errors. A set of difference orbits obtained by exciting the correctors along the beamline is taken, yielding the measured response matrix. An iterative procedure is invoked and the quadrupole errors as well as beam position monitors and corrector calibration factors are obtained. Here we present details of the method and results of first measurements at CEBAF in early 2011.

  9. Gap Test Calibrations and Their Scaling

    NASA Astrophysics Data System (ADS)

    Sandusky, Harold

    2011-06-01

    Common tests for measuring the threshold for shock initiation are the NOL large scale gap test (LSGT) with a 50.8-mm diameter donor/gap and the expanded large scale gap test (ELSGT) with a 95.3-mm diameter donor/gap. Despite the same specifications for the explosive donor and polymethyl methacrylate (PMMA) gap in both tests, calibration of shock pressure in the gap versus distance from the donor scales by a factor of 1.75, not the 1.875 difference in their sizes. Recently reported model calculations suggest that the scaling discrepancy results from the viscoelastic properties of PMMA in combination with different methods for obtaining shock pressure. This is supported by the consistent scaling of these donors when calibrated in water-filled aquariums. Calibrations with water gaps will be provided and compared with PMMA gaps. Scaling for other donor systems will also be provided. Shock initiation data with water gaps will be reviewed.

  10. Gap Test Calibrations And Their Scalin

    NASA Astrophysics Data System (ADS)

    Sandusky, Harold

    2012-03-01

    Common tests for measuring the threshold for shock initiation are the NOL large scale gap test (LSGT) with a 50.8-mm diameter donor/gap and the expanded large scale gap test (ELSGT) with a 95.3-mm diameter donor/gap. Despite the same specifications for the explosive donor and polymethyl methacrylate (PMMA) gap in both tests, calibration of shock pressure in the gap versus distance from the donor scales by a factor of 1.75, not the 1.875 difference in their sizes. Recently reported model calculations suggest that the scaling discrepancy results from the viscoelastic properties of PMMA in combination with different methods for obtaining shock pressure. This is supported by the consistent scaling of these donors when calibrated in water-filled aquariums. Calibrations and their scaling are compared for other donors with PMMA gaps and for various donors in water.

  11. Calibration Results Of The Strofio Sensor

    NASA Astrophysics Data System (ADS)

    Livi, S. A.; Allegrini, F.; Miles, P. F.

    2013-12-01

    The sensor Strofio is a mass spectrometer, part of the Serena plasma/neutral particles package for the BepiColombo mission to Mercury. During several campaignes of calibraion at the Southwest Research Institute and at the University of Bern we calibrated the characteristics of the Flight Unit and determined the calibration factors of the sensor. All the measured responses of Strofio to external stimuly are compatible with the requirements necessary to characterize the tenuous exosphere of Mercury. In the measured particluar sensitivity (0.14 (cts/sec)/(1/cm3)), resolution (m/dm>90), mass range (4-60 + 80-120) and capability of background rejection ( > 40) are well fitted to the expected conditions around the planet. We present the current understanding of composition and variability of the Hemean exosphere, the derived physical measurables, and show the relevant Strofio calibration results.

  12. Calibration of the Urbana lidar system

    NASA Technical Reports Server (NTRS)

    Cerny, T.; Sechrist, C. F., Jr.

    1980-01-01

    A method for calibrating data obtained by the Urban sodium lidar system is presented. First, an expression relating the number of photocounts originating from a specific altitude range to the soodium concentration is developed. This relation is then simplified by normalizing the sodium photocounts with photocounts originating from the Rayleigh region of the atmosphere. To evaluate the calibration expression, the laser linewidth must be known. Therefore, a method for measuring the laser linewidth using a Fabry-Perot interferometer is given. The laser linewidth was found to be 6 + or - 2.5 pm. Problems due to photomultiplier tube overloading are discussed. Finally, calibrated data is presented. The sodium column abundance exhibits something close to a sinusoidal variation throughout the year with the winter months showing an enhancement of a factor of 5 to 7 over the summer months.

  13. Calibrated Measures for Breast Density Estimation

    PubMed Central

    Heine, John J.; Cao, Ke; Rollison, Dana E.

    2011-01-01

    Rationale and Objectives Breast density is a significant breast cancer risk factor measured from mammograms. Evidence suggests that the spatial variation in mammograms may also be associated with risk. We investigated the variation in calibrated mammograms as a breast cancer risk factor and explored its relationship with other measures of breast density using full field digital mammography (FFDM). Materials and Methods A matched case-control analysis was used to assess a spatial variation breast density measure in calibrated FFDM images, normalized for the image acquisition technique variation. Three measures of breast density were compared between cases and controls: (a) the calibrated average measure, (b) the calibrated variation measure, and (c) the standard percentage of breast density (PD) measure derived from operator-assisted labeling. Linear correlation and statistical relationships between these three breast density measures were also investigated. Results Risk estimates associated with the lowest to highest quartiles for the calibrated variation measure were greater in magnitude [odds ratios: 1.0 (ref.), 3.5, 6.3, and 11.3] than the corresponding risk estimates for quartiles of the standard PD measure [odds ratios: 1.0 (ref.), 2.3, 5.6, and 6.5] and the calibrated average measure [odds ratios: 1.0 (ref.), 2.4, 2.3, and 4.4]. The three breast density measures were highly correlated, showed an inverse relationship with breast area, and related by a mixed distribution relationship. Conclusion The three measures of breast density capture different attributes of the same data field. These preliminary findings indicate the variation measure is a viable automated method for assessing breast density. Insights gained by this work may be used to develop a standard for measuring breast density. PMID:21371912

  14. MODIS Solar Reflective Calibration Traceability

    NASA Technical Reports Server (NTRS)

    Xiong, Xiaoxiong; Butler, Jim

    2009-01-01

    Long-term climate data records often consist of observations made by multiple sensors. It is, therefore, extremely important to have instrument overlap, to be able to track instrument stability, to quantify, measurement uncertainties, and to establish absolute scale traceable to the International System of Units (SI). The Moderate Resolution Imaging Spectroradiometer (MODIS) is a key instrument for both the Terra and Aqua missions, which were launched in December 1999 and May 2002, respectively. It has 20 reflective solar bands (RSB) with wavelengths from 0.41 to 2.2 micrometers and observes the Earth at three nadir spatial resolutions: 0.25km, 0.5km, and 1km. MODIS RSB on-orbit calibration is reflectance based with reference to the bidirectional reflectance factor (BRF) of its on-board solar diffuser (SD). The SD BRF characterization was made pre-launch by the instrument vendor using reference samples traceable directly to the National Institute of Standards and Technology (NIST). On-orbit SD reflectance degradation is tracked by an on-board solar diffuser monitor (SDSM). This paper provides details of this calibration chain, from prelaunch to on-orbit operation, and associated uncertainty assessments. Using MODIS as an example, this paper also discusses challenges and key design requirements for future missions developed for accurate climate studies.

  15. Computerized tomography calibrator

    NASA Technical Reports Server (NTRS)

    Engel, Herbert P. (Inventor)

    1991-01-01

    A set of interchangeable pieces comprising a computerized tomography calibrator, and a method of use thereof, permits focusing of a computerized tomographic (CT) system. The interchangeable pieces include a plurality of nestable, generally planar mother rings, adapted for the receipt of planar inserts of predetermined sizes, and of predetermined material densities. The inserts further define openings therein for receipt of plural sub-inserts. All pieces are of known sizes and densities, permitting the assembling of different configurations of materials of known sizes and combinations of densities, for calibration (i.e., focusing) of a computerized tomographic system through variation of operating variables thereof. Rather than serving as a phanton, which is intended to be representative of a particular workpiece to be tested, the set of interchangeable pieces permits simple and easy standardized calibration of a CT system. The calibrator and its related method of use further includes use of air or of particular fluids for filling various openings, as part of a selected configuration of the set of pieces.

  16. CALIBRATION Galileo Scale Model

    E-print Network

    see Jupiter and some of its 4 largest moons, just as Galileo Galilei did in Italy in 1610. While youPRINTING CALIBRATION Galileo Scale Model PARTS SHEET 1: The High-Gain Antenna PRINT ON TRANSPARENCY MATERIAL Galileo's High-Gain Antenna (HGA) was designed to unfold like an umbrella. It needed to be folded

  17. Calibrated Peer Review

    NSDL National Science Digital Library

    Calibrated Peer Review

    This site presents a paper-writing and peer review tool that is available free to educators and students. Calibrated Peer Review is a Web-based program that enables frequent writing assignments even in large classes with limited instructional resources. The program is discipline and level independent.

  18. Thermistor mount efficiency calibration

    SciTech Connect

    Cable, J.W.

    1980-05-01

    Thermistor mount efficiency calibration is accomplished by use of the power equation concept and by complex signal-ratio measurements. A comparison of thermistor mounts at microwave frequencies is made by mixing the reference and the reflected signals to produce a frequency at which the amplitude and phase difference may be readily measured.

  19. Uncertainty in audiometer calibration

    NASA Astrophysics Data System (ADS)

    Aurélio Pedroso, Marcos; Gerges, Samir N. Y.; Gonçalves, Armando A., Jr.

    2004-02-01

    The objective of this work is to present a metrology study necessary for the accreditation of audiometer calibration procedures at the National Brazilian Institute of Metrology Standardization and Industrial Quality—INMETRO. A model for the calculation of measurement uncertainty was developed. Metrological aspects relating to audiometer calibration, traceability and measurement uncertainty were quantified through comparison between results obtained at the Industrial Noise Laboratory—LARI of the Federal University of Santa Catarina—UFSC and the Laboratory of Electric/acoustics—LAETA of INMETRO. Similar metrological performance of the measurement system used in both laboratories was obtained, indicating that the interlaboratory results are compatible with the expected values. The uncertainty calculation was based on the documents: EA-4/02 Expression of the Uncertainty of Measurement in Calibration (European Co-operation for Accreditation 1999 EA-4/02 p 79) and Guide to the Expression of Uncertainty in Measurement (International Organization for Standardization 1993 1st edn, corrected and reprinted in 1995, Geneva, Switzerland). Some sources of uncertainty were calculated theoretically (uncertainty type B) and other sources were measured experimentally (uncertainty type A). The global value of uncertainty calculated for the sound pressure levels (SPLs) is similar to that given by other calibration institutions. The results of uncertainty related to measurements of SPL were compared with the maximum uncertainties Umax given in the standard IEC 60645-1: 2001 (International Electrotechnical Commission 2001 IEC 60645-1 Electroacoustics—Audiological Equipment—Part 1:—Pure-Tone Audiometers).

  20. EPOXI instrument calibration

    NASA Astrophysics Data System (ADS)

    Klaasen, Kenneth P.; A'Hearn, Michael; Besse, Sebastian; Bodewits, Dennis; Carcich, Brian; Farnham, Tony; Feaga, Lori; Groussin, Olivier; Hampton, Donald; Huisjen, Marty; Kelley, Michael S.; McLaughlin, Stephanie; Merlin, Frederic; Protopapa, Silvia; Sunshine, Jessica; Thomas, Peter; Wellnitz, Dennis

    2013-07-01

    NASA's EPOXI mission used the Deep Impact (DI) Flyby spacecraft to deliver a payload of three scientific instruments, two visible cameras and an IR spectrometer, to a close flyby of Comet 103P/Hartley 2 in November 2010. Interpretation of the scientific measurements made using these instruments depends on accurate calibration of the instruments' performance. Updates to the instrument calibrations achieved during the Deep Impact primary mission and results of continued monitoring of their performance during EPOXI are reported here. The instruments' performance has remained remarkably stable over the nearly 7 years of flight. Significant improvements in the understanding and calibration of the IR spectrometer response non-linearity, time-varying background level, flat field, wavelength map, and absolute spectral response have been achieved. Techniques for reducing some semi-coherent horizontal noise stripes in the visible cameras' readouts were developed, and some adjustments have been made to their absolute radiometric conversion constants. The data processing pipeline has been updated to incorporate the improvements in the instrument calibrations.

  1. The JWST Calibration Pipeline

    NASA Astrophysics Data System (ADS)

    Chen, Christine; Muzerolle, James; Van Dyke Dixon, William; Izela Diaz, Rosa; Bushouse, Howard A.

    2015-01-01

    The James Webb Space Telescope will launch in 2018 and carry four science instruments that will observe the sky at 0.7 - 29 micron: the Near Infrared Camera (NIRCam), the Near Infrared Imager and Slitless Spectrograph (NIRISS), the Near Infrared Spectrograph (NIRSpec), and the Mid Infrared Instrument (MIRI). The Space Telescope Science Institute (STScI) is currently building a data reduction pipeline that will provide not only basic calibrated data but also higher level science products. All of the JWST detectors will be operated in non-destructive readout mode. Therefore, the first step in the pipeline will be to calculate the slopes of indivudal non-destructive readout ramps or integrations. The next step will be to generate calibrated slope images that are represent the basic calibrated data. The final step will be to combine data taken across multiple integrations and exposure. For the direct imaging and integral field spectroscopy modes, the pipeline will produce calibrated mosaicks. For the coronagraphic modes, the pipeline will produce contrast curves and PSF subtracted images.

  2. Optical detector calibrator system

    NASA Technical Reports Server (NTRS)

    Strobel, James P. (Inventor); Moerk, John S. (Inventor); Youngquist, Robert C. (Inventor)

    1996-01-01

    An optical detector calibrator system simulates a source of optical radiation to which a detector to be calibrated is responsive. A light source selected to emit radiation in a range of wavelengths corresponding to the spectral signature of the source is disposed within a housing containing a microprocessor for controlling the light source and other system elements. An adjustable iris and a multiple aperture filter wheel are provided for controlling the intensity of radiation emitted from the housing by the light source to adjust the simulated distance between the light source and the detector to be calibrated. The geared iris has an aperture whose size is adjustable by means of a first stepper motor controlled by the microprocessor. The multiple aperture filter wheel contains neutral density filters of different attenuation levels which are selectively positioned in the path of the emitted radiation by a second stepper motor that is also controlled by the microprocessor. An operator can select a number of detector tests including range, maximum and minimum sensitivity, and basic functionality. During the range test, the geared iris and filter wheel are repeatedly adjusted by the microprocessor as necessary to simulate an incrementally increasing simulated source distance. A light source calibration subsystem is incorporated in the system which insures that the intensity of the light source is maintained at a constant level over time.

  3. Simplified Vicarious Radiometric Calibration

    NASA Technical Reports Server (NTRS)

    Stanley, Thomas; Ryan, Robert; Holekamp, Kara; Pagnutti, Mary

    2010-01-01

    A measurement-based radiance estimation approach for vicarious radiometric calibration of spaceborne multispectral remote sensing systems has been developed. This simplified process eliminates the use of radiative transfer codes and reduces the number of atmospheric assumptions required to perform sensor calibrations. Like prior approaches, the simplified method involves the collection of ground truth data coincident with the overpass of the remote sensing system being calibrated, but this approach differs from the prior techniques in both the nature of the data collected and the manner in which the data are processed. In traditional vicarious radiometric calibration, ground truth data are gathered using ground-viewing spectroradiometers and one or more sun photometer( s), among other instruments, located at a ground target area. The measured data from the ground-based instruments are used in radiative transfer models to estimate the top-of-atmosphere (TOA) target radiances at the time of satellite overpass. These TOA radiances are compared with the satellite sensor readings to radiometrically calibrate the sensor. Traditional vicarious radiometric calibration methods require that an atmospheric model be defined such that the ground-based observations of solar transmission and diffuse-to-global ratios are in close agreement with the radiative transfer code estimation of these parameters. This process is labor-intensive and complex, and can be prone to errors. The errors can be compounded because of approximations in the model and inaccurate assumptions about the radiative coupling between the atmosphere and the terrain. The errors can increase the uncertainty of the TOA radiance estimates used to perform the radiometric calibration. In comparison, the simplified approach does not use atmospheric radiative transfer models and involves fewer assumptions concerning the radiative transfer properties of the atmosphere. This new technique uses two neighboring uniform ground target areas having different reflectance values. The target areas can be natural or artificial and must be large enough to minimize adjacent-pixel contamination effects. The radiative coupling between the atmosphere and the terrain needs to be approximately the same for the two targets. This condition can be met for relatively uniform backgrounds when the distance between the targets is within a few hundred meters. For each target area, the radiance leaving the ground in the direction of the satellite is measured with a radiometrically calibrated spectroradiometer. Using the radiance measurements from the two targets, atmospheric adjacency and atmospheric scattering effects can be subtracted, thereby eliminating many assumptions about the atmosphere and the radiative interaction between the atmosphere and the terrain. In addition, the radiometrically calibrated spectroradiometer can be used with a known reflectance target to estimate atmospheric transmission and diffuse- to-global ratios without the need for ancillary sun photometers. Several comparisons between the simplified method and traditional techniques were found to agree within a few percent. Hence, the simplified method reduces the overall complexity of performing vicarious calibrations and can serve as a method for validating traditional radiative transfer models

  4. Mercury CEM Calibration

    SciTech Connect

    John F. Schabron; Joseph F. Rovani; Susan S. Sorini

    2007-03-31

    The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005, requires that calibration of mercury continuous emissions monitors (CEMs) be performed with NIST-traceable standards. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The traceability protocol will be written by EPA. Traceability will be based on the actual analysis of the output of each calibration unit at several concentration levels ranging from about 2-40 ug/m{sup 3}, and this analysis will be directly traceable to analyses by NIST using isotope dilution inductively coupled plasma/mass spectrometry (ID ICP/MS) through a chain of analyses linking the calibration unit in the power plant to the NIST ID ICP/MS. Prior to this project, NIST did not provide a recommended mercury vapor pressure equation or list mercury vapor pressure in its vapor pressure database. The NIST Physical and Chemical Properties Division in Boulder, Colorado was subcontracted under this project to study the issue in detail and to recommend a mercury vapor pressure equation that the vendors of mercury vapor pressure calibration units can use to calculate the elemental mercury vapor concentration in an equilibrium chamber at a particular temperature. As part of this study, a preliminary evaluation of calibration units from five vendors was made. The work was performed by NIST in Gaithersburg, MD and Joe Rovani from WRI who traveled to NIST as a Visiting Scientist.

  5. An open-label, multicenter study to evaluate the safe and effective use of the single-use autoinjector with an Avonex® prefilled syringe in multiple sclerosis subjects

    PubMed Central

    2011-01-01

    Background The ability to self-inject in patients with multiple sclerosis (MS) has been associated with a reduced risk of missed injections and drug discontinuation, and a beneficial effect on patients' independence. However, injection anxiety, needle phobia and disease-related disability are major barriers to a patient's ability to self-administer treatment. Use of an autoinjector may improve patients' ability to self-inject. This study evaluated the safe and effective use of Avonex Pen™ (prefilled pen), a single use autoinjector, for intramuscular delivery of interferon beta-1a (IM IFN?-1a, Avonex) in MS patients. Methods This was a Phase IIIb, open-label, single-country, multicenter trial in MS patients currently using IM IFN?-1a prefilled syringes. Patients received weekly 30 mcg IM IFN?-1a treatment over 4 weeks. On Day 1, patients self-administered IM IFN?-1a using a prefilled syringe at the clinic. On Day 8, patients received training on the prefilled pen and self-administered IM IFN?-1a using the device. On Day 15, patients self-administered IM IFN?-1a at home using the prefilled pen. A final injection occurred at the clinic on Day 22 when patients self-administered IM IFN?-1a using the prefilled pen while clinic staff observed and completed a detailed questionnaire documenting patients' ability to self-inject with the device. Serum neopterin levels were evaluated pre and post-injection on Days 1 and 8. Adverse events were monitored throughout. Results Seventy-one (96%) patients completed the study. The overall success rate in safely and effectively using the prefilled pen was 89%. No device malfunctions occurred. One unsuccessful administration occurred at Day 22 due to patient error; no patient injury resulted. Patients gave the prefilled pen high ratings (8.7-9.3) on a 10-point scale for ease of use (0 = extremely difficult, 10 = extremely easy). Ninety-four percent of patients preferred the prefilled pen over the prefilled syringe. Induction of serum neopterin levels, serving as a biomarker for type 1 interferon action, was similar to that of the prefilled syringe. The prefilled pen demonstrated a safety profile comparable to the prefilled syringe. Conclusions The prefilled pen is a safe and effective device for administration of IM IFN?-1a and represents an alternative method for self-injection for MS patients using this therapy. Trial registration This study is registered at clinicaltrials.gov, identifier: NCT00828204 PMID:21999176

  6. New approach to calibrating bed load samplers ( calibration curves).

    USGS Publications Warehouse

    Hubbell, D.W.; Stevens, H.H.; Skinner, J.V.

    1985-01-01

    Calibration curves are derived by two independent methods using data collected with prototype versions of the Helley-Smith sampler in a large calibration facility capable of continuously measuring transport rates across a 9ft (2.7m) width. Results from both methods agree. Composite calibration curves are obtained for six different versions of the sampler.-from ASCE Publications Information

  7. Procedures used in the calibration of ac calibrators

    NASA Astrophysics Data System (ADS)

    Salazar, M. T.

    1991-02-01

    An automatic calibration system used in the calibration of all precision ac calibrators is described. The system includes an ac-dc Transfer Standard, a dc Voltage Standard, and a high resolution digital multimeter, with an IBM-XT Personal Computer for data acquisition and analysis. Specialized instrumentation and measurement techniques make it possible to achieve high accuracy measurements with repeatability.

  8. MICROWAVE RADIOMETER INTER-CALIBRATION USING THE VICARIOUS CALIBRATION METHOD

    E-print Network

    Ruf, Christopher

    MICROWAVE RADIOMETER INTER-CALIBRATION USING THE VICARIOUS CALIBRATION METHOD Darren McKague Chris of Ruf, and Brown and Ruf, have been used to assess the calibration of the WindSat radiometer as well as the biases of the TMI, SSM/I F13 and SSM/I F14 radiometers relative to WindSat. WindSat biases computed

  9. Multivariate calibration applied to the quantitative analysis of infrared spectra

    SciTech Connect

    Haaland, D.M.

    1991-01-01

    Multivariate calibration methods are very useful for improving the precision, accuracy, and reliability of quantitative spectral analyses. Spectroscopists can more effectively use these sophisticated statistical tools if they have a qualitative understanding of the techniques involved. A qualitative picture of the factor analysis multivariate calibration methods of partial least squares (PLS) and principal component regression (PCR) is presented using infrared calibrations based upon spectra of phosphosilicate glass thin films on silicon wafers. Comparisons of the relative prediction abilities of four different multivariate calibration methods are given based on Monte Carlo simulations of spectral calibration and prediction data. The success of multivariate spectral calibrations is demonstrated for several quantitative infrared studies. The infrared absorption and emission spectra of thin-film dielectrics used in the manufacture of microelectronic devices demonstrate rapid, nondestructive at-line and in-situ analyses using PLS calibrations. Finally, the application of multivariate spectral calibrations to reagentless analysis of blood is presented. We have found that the determination of glucose in whole blood taken from diabetics can be precisely monitored from the PLS calibration of either mind- or near-infrared spectra of the blood. Progress toward the non-invasive determination of glucose levels in diabetics is an ultimate goal of this research. 13 refs., 4 figs.

  10. Mercury Calibration System

    SciTech Connect

    John Schabron; Eric Kalberer; Joseph Rovani; Mark Sanderson; Ryan Boysen; William Schuster

    2009-03-11

    U.S. Environmental Protection Agency (EPA) Performance Specification 12 in the Clean Air Mercury Rule (CAMR) states that a mercury CEM must be calibrated with National Institute for Standards and Technology (NIST)-traceable standards. In early 2009, a NIST traceable standard for elemental mercury CEM calibration still does not exist. Despite the vacature of CAMR by a Federal appeals court in early 2008, a NIST traceable standard is still needed for whatever regulation is implemented in the future. Thermo Fisher is a major vendor providing complete integrated mercury continuous emissions monitoring (CEM) systems to the industry. WRI is participating with EPA, EPRI, NIST, and Thermo Fisher towards the development of the criteria that will be used in the traceability protocols to be issued by EPA. An initial draft of an elemental mercury calibration traceability protocol was distributed for comment to the participating research groups and vendors on a limited basis in early May 2007. In August 2007, EPA issued an interim traceability protocol for elemental mercury calibrators. Various working drafts of the new interim traceability protocols were distributed in late 2008 and early 2009 to participants in the Mercury Standards Working Committee project. The protocols include sections on qualification and certification. The qualification section describes in general terms tests that must be conducted by the calibrator vendors to demonstrate that their calibration equipment meets the minimum requirements to be established by EPA for use in CAMR monitoring. Variables to be examined include linearity, ambient temperature, back pressure, ambient pressure, line voltage, and effects of shipping. None of the procedures were described in detail in the draft interim documents; however they describe what EPA would like to eventually develop. WRI is providing the data and results to EPA for use in developing revised experimental procedures and realistic acceptance criteria based on actual capabilities of the current calibration technology. As part of the current effort, WRI worked with Thermo Fisher elemental mercury calibrator units to conduct qualification experiments to demonstrate their performance characteristics under a variety of conditions and to demonstrate that they qualify for use in the CEM calibration program. Monitoring of speciated mercury is another concern of this research. The mercury emissions from coal-fired power plants are comprised of both elemental and oxidized mercury. Current CEM analyzers are designed to measure elemental mercury only. Oxidized mercury must first be converted to elemental mercury prior to entering the analyzer inlet in order to be measured. CEM systems must demonstrate the ability to measure both elemental and oxidized mercury. This requires the use of oxidized mercury generators with an efficient conversion of the oxidized mercury to elemental mercury. There are currently two basic types of mercuric chloride (HgCl{sub 2}) generators used for this purpose. One is an evaporative HgCl{sub 2} generator, which produces gas standards of known concentration by vaporization of aqueous HgCl{sub 2} solutions and quantitative mixing with a diluent carrier gas. The other is a device that converts the output from an elemental Hg generator to HgCl{sub 2} by means of a chemical reaction with chlorine gas. The Thermo Fisher oxidizer system involves reaction of elemental mercury vapor with chlorine gas at an elevated temperature. The draft interim protocol for oxidized mercury units involving reaction with chlorine gas requires the vendors to demonstrate high efficiency of oxidation of an elemental mercury stream from an elemental mercury vapor generator. The Thermo Fisher oxidizer unit is designed to operate at the power plant stack at the probe outlet. Following oxidation of elemental mercury from reaction with chlorine gas, a high temperature module reduces the mercuric chloride back to elemental mercury. WRI conducted work with a custom laboratory configured stand-alone oxidized mercury generator unit prov

  11. Mercury CEM Calibration

    SciTech Connect

    John Schabron; Joseph Rovani; Mark Sanderson

    2008-02-29

    Mercury continuous emissions monitoring systems (CEMS) are being implemented in over 800 coal-fired power plant stacks. The power industry desires to conduct at least a full year of monitoring before the formal monitoring and reporting requirement begins on January 1, 2009. It is important for the industry to have available reliable, turnkey equipment from CEM vendors. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The generators are used to calibrate mercury CEMs at power plant sites. The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005 requires that calibration be performed with NIST-traceable standards (Federal Register 2007). Traceability procedures will be defined by EPA. An initial draft traceability protocol was issued by EPA in May 2007 for comment. In August 2007, EPA issued an interim traceability protocol for elemental mercury generators (EPA 2007). The protocol is based on the actual analysis of the output of each calibration unit at several concentration levels ranging initially from about 2-40 {micro}g/m{sup 3} elemental mercury, and in the future down to 0.2 {micro}g/m{sup 3}, and this analysis will be directly traceable to analyses by NIST. The document is divided into two separate sections. The first deals with the qualification of generators by the vendors for use in mercury CEM calibration. The second describes the procedure that the vendors must use to certify the generator models that meet the qualification specifications. The NIST traceable certification is performance based, traceable to analysis using isotope dilution inductively coupled plasma/mass spectrometry performed by NIST in Gaithersburg, MD. The outputs of mercury generators are compared to one another using a nesting procedure which allows direct comparison of one generator with another and eliminates analyzer variability effects. The qualification portion of the EPA interim traceability protocol requires the vendors to define generator performance as affected by variables such as pressure, temperature, line voltage, and shipping. WRI is focusing efforts to determine actual generator performance related to the variables defined in the qualification portion of the interim protocol. The protocol will then be further revised by EPA based on what can actually be achieved with the generators. Another focus of the study is to evaluate approaches for field verification of generator performance. Upcoming work includes evaluation of oxidized mercury calibration generators, for which a separate protocol will be prepared by EPA. In addition, the variability of the spectrometers/analyzers under various environmental conditions needs to be defined and understood better. A main objective of the current work is to provide data on the performance and capabilities of elemental mercury generator/calibration systems for the development of realistic NIST traceability protocols for mercury vapor standards for continuous emission CEM calibration. This work is providing a direct contribution to the enablement of continuous emissions monitoring at coal-fired power plants in conformance with the CAMR. EPA Specification 12 states that mercury CEMs must be calibrated with NIST-traceable standards (Federal Register 2005). The initial draft of an elemental mercury generator traceability protocol was circulated by EPA in May 2007 for comment, and an interim protocol was issued in August 2007 (EPA 2007). Initially it was assumed that the calibration and implementation of mercury CEMs would be relatively simple, and implementation would follow the implementation of the Clean Air Interstate Rule (CAIR) SO{sub 2} and NO{sub x} monitoring, and sulfur emissions cap and trade. However, mercury has proven to be significantly more difficult

  12. Calibration of Germanium Resistance Thermometers

    NASA Technical Reports Server (NTRS)

    Ladner, D.; Urban, E.; Mason, F. C.

    1987-01-01

    Largely completed thermometer-calibration cryostat and probe allows six germanium resistance thermometers to be calibrated at one time at superfluid-helium temperatures. In experiments involving several such thermometers, use of this calibration apparatus results in substantial cost savings. Cryostat maintains temperature less than 2.17 K through controlled evaporation and removal of liquid helium from Dewar. Probe holds thermometers to be calibrated and applies small amount of heat as needed to maintain precise temperature below 2.17 K.

  13. Statistical design of mass spectrometry calibration procedures

    SciTech Connect

    Bayne, C.K.

    1996-11-01

    The main objective of this task was to agree on calibration procedures to estimate the system parameters (i.e., dead-time correction, ion-counting conversion efficiency, and detector efficiency factors) for SAL`s new Finnigan MAT-262 mass spectrometer. SAL will use this mass spectrometer in a clean-laboratory which was opened in December 1995 to measure uranium and plutonium isotopes on environmental samples. The Finnigan MAT-262 mass spectrometer has a multi-detector system with seven Faraday cup detectors and one ion- counter for the measurement of very small signals (e.g. 10{sup -17} Ampere range). ORNL has made preliminary estimates of the system parameters based on SAL`s experimental data measured in late 1994 when the Finnigan instrument was relatively new. SAL generated additional data in 1995 to verify the calibration procedures for estimating the dead-time correction factor, the ion-counting conversion factor and the Faraday cup detector efficiency factors. The system parameters estimated on the present data will have to be reestablished when the Finnigan MAT-262 is moved-to the new clean- laboratory. Different methods will be used to analyzed environmental samples than the current measurement methods being used. For example, the environmental samples will be electroplated on a single filament rather than using the current two filament system. An outline of the calibration standard operating procedure (SOP) is included.

  14. Calibration Pipeline for VIR Data

    NASA Astrophysics Data System (ADS)

    Carraro, F.; Fonte, S.; Coradini, A.; de Sanctis, M. C.; Capaccioni, F.; Capria, M. T.; Filacchione, G.; Ammannito, E.; Tosi, F.; Cartacci, M.; Noschese, R.

    2012-03-01

    The VIR-MS instrument team has realized a calibration tool that has the goal of producing calibrated (1b level) data starting from the raw (1a level) ones. This tool, developed by using the Java language, has been called "VIR Calibration".

  15. Internet-based calibration of a multifunction calibrator

    SciTech Connect

    BUNTING BACA,LISA A.; DUDA JR.,LEONARD E.; WALKER,RUSSELL M.; OLDHAM,NILE; PARKER,MARK

    2000-04-17

    A new way of providing calibration services is evolving which employs the Internet to expand present capabilities and make the calibration process more interactive. Sandia National Laboratories and the National Institute of Standards and Technology are collaborating to set up and demonstrate a remote calibration of multifunction calibrators using this Internet-based technique that is becoming known as e-calibration. This paper describes the measurement philosophy and the Internet resources that can provide real-time audio/video/data exchange, consultation and training, as well as web-accessible test procedures, software and calibration reports. The communication system utilizes commercial hardware and software that should be easy to integrate into most calibration laboratories.

  16. Internet-Based Calibration of a Multifunction Calibrator

    SciTech Connect

    BUNTING BACA,LISA A.; DUDA JR.,LEONARD E.; WALKER,RUSSELL M.; OLDHAM,NILE; PARKER,MARK

    2000-12-19

    A new way of providing calibration services is evolving which employs the Internet to expand present capabilities and make the calibration process more interactive. Sandia National Laboratories and the National Institute of Standards and Technology are collaborating to set up and demonstrate a remote calibration of multijunction calibrators using this Internet-based technique that is becoming known as e-calibration. This paper describes the measurement philosophy and the Internet resources that can provide real-time audio/video/data exchange, consultation and training, as well as web-accessible test procedures, software and calibration reports. The communication system utilizes commercial hardware and software that should be easy to integrate into most calibration laboratories.

  17. Environmental calibration chamber operations

    NASA Technical Reports Server (NTRS)

    Lester, D. L.

    1988-01-01

    Thermal vacuum capabilities are provided for the development, calibration, and functional operation checks of flight sensors, sources, and laboratory and field instruments. Two systems are available. The first is a 46 cm diameter diffusion pumped vacuum chambler of the bell jar variety. It has an internal thermal shroud, LN2 old trap, two viewing ports, and various electrical and fluid feedthroughs. The other, also an oil diffusion pumped system, consists of a 1.8 m diameter by 2.5 m long stainless steel vacuum tank, associated pumping and control equipment, a liquid nitrogen storage and transfer system and internal IR/visible calibration sources. This is a two story system with the chamber located on one floor and the pumping/cryogenic systems located on the floor below.

  18. Calibrated vapor generator source

    DOEpatents

    Davies, John P. (Idaho Falls, ID); Larson, Ronald A. (Idaho Falls, ID); Goodrich, Lorenzo D. (Shelley, ID); Hall, Harold J. (Idaho Falls, ID); Stoddard, Billy D. (Idaho Falls, ID); Davis, Sean G. (Idaho Falls, ID); Kaser, Timothy G. (Idaho Falls, ID); Conrad, Frank J. (Albuquerque, NM)

    1995-01-01

    A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet.

  19. Calibrated vapor generator source

    DOEpatents

    Davies, J.P.; Larson, R.A.; Goodrich, L.D.; Hall, H.J.; Stoddard, B.D.; Davis, S.G.; Kaser, T.G.; Conrad, F.J.

    1995-09-26

    A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet. 10 figs.

  20. Mesoscale hybrid calibration artifact

    SciTech Connect

    Tran, Hy D. (Albuquerque, NM); Claudet, Andre A. (Albuquerque, NM); Oliver, Andrew D. (Waltham, MA)

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  1. Calibrated Properties Model

    SciTech Connect

    H. H. Liu

    2003-02-14

    This report has documented the methodologies and the data used for developing rock property sets for three infiltration maps. Model calibration is necessary to obtain parameter values appropriate for the scale of the process being modeled. Although some hydrogeologic property data (prior information) are available, these data cannot be directly used to predict flow and transport processes because they were measured on scales smaller than those characterizing property distributions in models used for the prediction. Since model calibrations were done directly on the scales of interest, the upscaling issue was automatically considered. On the other hand, joint use of data and the prior information in inversions can further increase the reliability of the developed parameters compared with those for the prior information. Rock parameter sets were developed for both the mountain and drift scales because of the scale-dependent behavior of fracture permeability. Note that these parameter sets, except those for faults, were determined using the 1-D simulations. Therefore, they cannot be directly used for modeling lateral flow because of perched water in the unsaturated zone (UZ) of Yucca Mountain. Further calibration may be needed for two- and three-dimensional modeling studies. As discussed above in Section 6.4, uncertainties for these calibrated properties are difficult to accurately determine, because of the inaccuracy of simplified methods for this complex problem or the extremely large computational expense of more rigorous methods. One estimate of uncertainty that may be useful to investigators using these properties is the uncertainty used for the prior information. In most cases, the inversions did not change the properties very much with respect to the prior information. The Output DTNs (including the input and output files for all runs) from this study are given in Section 9.4.

  2. Calibrated Properties Model

    SciTech Connect

    T. Ghezzehej

    2004-10-04

    The purpose of this model report is to document the calibrated properties model that provides calibrated property sets for unsaturated zone (UZ) flow and transport process models (UZ models). The calibration of the property sets is performed through inverse modeling. This work followed, and was planned in, ''Technical Work Plan (TWP) for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Sections 1.2.6 and 2.1.1.6). Direct inputs to this model report were derived from the following upstream analysis and model reports: ''Analysis of Hydrologic Properties Data'' (BSC 2004 [DIRS 170038]); ''Development of Numerical Grids for UZ Flow and Transport Modeling'' (BSC 2004 [DIRS 169855]); ''Simulation of Net Infiltration for Present-Day and Potential Future Climates'' (BSC 2004 [DIRS 170007]); ''Geologic Framework Model'' (GFM2000) (BSC 2004 [DIRS 170029]). Additionally, this model report incorporates errata of the previous version and closure of the Key Technical Issue agreement TSPAI 3.26 (Section 6.2.2 and Appendix B), and it is revised for improved transparency.

  3. An improved procedure for developing a calibrated hourly simulation model of an electrically heated and cooled commercial building

    E-print Network

    Bou-Saada, Tarek Edmond

    1994-01-01

    With the increased use of building energy simulation programs, calibration of simulated data to measured data has been recognized as an important factor in substantiating how well the model fits a real building. Model calibration to measured monthly...

  4. A variable acceleration calibration system

    NASA Astrophysics Data System (ADS)

    Johnson, Thomas H.

    2011-12-01

    A variable acceleration calibration system that applies loads using gravitational and centripetal acceleration serves as an alternative, efficient and cost effective method for calibrating internal wind tunnel force balances. Two proof-of-concept variable acceleration calibration systems are designed, fabricated and tested. The NASA UT-36 force balance served as the test balance for the calibration experiments. The variable acceleration calibration systems are shown to be capable of performing three component calibration experiments with an approximate applied load error on the order of 1% of the full scale calibration loads. Sources of error are indentified using experimental design methods and a propagation of uncertainty analysis. Three types of uncertainty are indentified for the systems and are attributed to prediction error, calibration error and pure error. Angular velocity uncertainty is shown to be the largest indentified source of prediction error. The calibration uncertainties using a production variable acceleration based system are shown to be potentially equivalent to current methods. The production quality system can be realized using lighter materials and a more precise instrumentation. Further research is needed to account for balance deflection, forcing effects due to vibration, and large tare loads. A gyroscope measurement technique is shown to be capable of resolving the balance deflection angle calculation. Long term research objectives include a demonstration of a six degree of freedom calibration, and a large capacity balance calibration.

  5. Automatic force balance calibration system

    NASA Technical Reports Server (NTRS)

    Ferris, Alice T. (Inventor)

    1996-01-01

    A system for automatically calibrating force balances is provided. The invention uses a reference balance aligned with the balance being calibrated to provide superior accuracy while minimizing the time required to complete the calibration. The reference balance and the test balance are rigidly attached together with closely aligned moment centers. Loads placed on the system equally effect each balance, and the differences in the readings of the two balances can be used to generate the calibration matrix for the test balance. Since the accuracy of the test calibration is determined by the accuracy of the reference balance and current technology allows for reference balances to be calibrated to within .+-.0.05%, the entire system has an accuracy of a .+-.0.2%. The entire apparatus is relatively small and can be mounted on a movable base for easy transport between test locations. The system can also accept a wide variety of reference balances, thus allowing calibration under diverse load and size requirements.

  6. Self-Calibrating Pressure Transducer

    NASA Technical Reports Server (NTRS)

    Lueck, Dale E. (Inventor)

    2006-01-01

    A self-calibrating pressure transducer is disclosed. The device uses an embedded zirconia membrane which pumps a determined quantity of oxygen into the device. The associated pressure can be determined, and thus, the transducer pressure readings can be calibrated. The zirconia membrane obtains oxygen .from the surrounding environment when possible. Otherwise, an oxygen reservoir or other source is utilized. In another embodiment, a reversible fuel cell assembly is used to pump oxygen and hydrogen into the system. Since a known amount of gas is pumped across the cell, the pressure produced can be determined, and thus, the device can be calibrated. An isolation valve system is used to allow the device to be calibrated in situ. Calibration is optionally automated so that calibration can be continuously monitored. The device is preferably a fully integrated MEMS device. Since the device can be calibrated without removing it from the process, reductions in costs and down time are realized.

  7. Multigamma-ray calibration sources

    SciTech Connect

    Meyer, R.A.; Massey, T.N.

    1983-05-01

    We have calibrated a self-consistent set of multigamma-ray standards using the automated multi-spectrometry ..gamma..-ray counting facility at LLNL's Nuclear Chemistry Division. Pure sources of long-lived activity were produced by mass separation and/or chemical purification. The sources were counted individually and in combination on several different calibrated spectrometer systems. These systems utilize various detectors ranging from small (x-ray) detectors to large volume high-purity Ge detectors. This has allowed the use of the most ideal individual detector-efficiency characteristics for the determination of the relative ..gamma..-ray intensities. Precise energy measurements, reported earlier (Meyer, 1976) have been performed by an independent method. Both the energy and ..gamma..-ray-emission probabilities determined compare well with independently established values such as the recent ICRM intercomparison of /sup 152/Eu. We discuss our investigations aimed at resolving the shape of the efficiency response function up to 10 MeV for large volume Ge(Li) and high-purity Ge detectors. Recent results on the ..gamma..-ray-emission probabilities per decay for /sup 149/Gd and /sup 168/Tm multigamma-ray sources are discussed. For /sup 168/Tm, we deduce a 0.01% ..beta../sup -/ branch to the 87.73-keV level in /sup 168/Yb rather than the previous value which was a factor of 200 greater. In addition, we describe current cooperative efforts aimed at establishing a consistent set of data for short-lived fission products. Included are recent measurements on the bromine fission products with ..gamma.. rays up to 7 MeV.

  8. Miniaturized salting-out liquid-liquid extraction in a coupled-syringe system combined with HPLC-UV for extraction and determination of sulfanilamide.

    PubMed

    Sereshti, Hassan; Khosraviani, Marzieh; Sadegh Amini-Fazl, Mohammad

    2014-04-01

    In salting-out liquid-liquid extraction (SALLE) technique, water-miscible organic solvents are used for extraction of polar analytes from saline solutions. In this study, for the first time, a coupled 1-mL syringes system was utilized to perform a miniaturized SALLE method. Sulfanilamide antibiotic was extracted and determined via the developed method followed by high performance liquid chromatography-ultraviolet detection (HPLC-UV). The extraction process was carried out by rapid shooting of acetonitrile as extraction solvent (syringe B) into saline aqueous sample solution (syringe A), and then the shooting was repeated several times at a rate of 1 cycles(-1). Thereby, an extremely large contact surface area was created between phases and led to a rapid equilibrium and mass transfer. In order to improve the efficiency of the method, the effect of extraction solvent (type and volume), shooting times, salt concentration, and pH on the extraction efficiency was investigated. The best performance of the method was achieved with 250 µL of acetonitrile, salt concentration of 250 mg mL(-1), pH of 7, and shooting times of 5. The linear dynamic range was 0.001-10 µg mL(-1) with the determination coefficient of 0.9999. The relative standard deviation (RSD; n=3, C=5 µg mL(-1)), and the limit of detection (LOD) were 1.55% and 0.3 ng mL(-1), respectively. The developed technique was successfully applied to genuine samples of tea, water, milk, honey, human urine, plasma and blood. PMID:24607127

  9. Novel one-step headspace dynamic in-syringe liquid phase derivatization-extraction technique for the determination of aqueous aliphatic amines by liquid chromatography with fluorescence detection.

    PubMed

    Muniraj, Sarangapani; Shih, Hou-Kung; Chen, Ying-Fang; Hsiech, Chunming; Ponnusamy, Vinoth Kumar; Jen, Jen-Fon

    2013-06-28

    A novel one-step headspace (HS) dynamic in-syringe (DIS) based liquid-phase derivatization-extraction (LPDE) technique has been developed for the selective determination of two short-chain aliphatic amines (SCAAs) in aqueous samples using high performance liquid chromatography (HPLC) with fluorescence detection (FLD). Methylamine (MA) and dimethylamine (DMA) were selected as model compounds of SCAAs. In this method, a micro-syringe pre-filled with derivatizing reagent solution (9-fluorenylmethyl chloroformate) in the barrel was applied to achieve the simultaneous derivatization and extraction of two methylamines evolved from alkalized aqueous samples through the automated reciprocated movements of syringe plunger. After the derivatization-extraction process, the derivatized phase was directly injected into HPLC-FLD for analysis. Parameters influencing the evolution of methylamines and the HS-DIS-LPDE efficiency, including sample pH and temperature, sampling time, as well as the composition of derivatization reagent, reaction temperature, and frequency of reciprocated plunger movements, were thoroughly examined and optimized. Under optimal conditions, detections were linear in the range of 25-500?gL(-1) for MA and DMA with correlation coefficients all above 0.995. The limits of detection (based on S/N=3) were 5 and 19ngmL(-1) for MA and DMA, respectively. The applicability of the developed method was demonstrated for the determination of MA and DMA in real water samples without any prior cleanup of the sample. The present method provides a simple, selective, automated, low cost and eco-friendly procedure to determine aliphatic amines in aqueous samples. PMID:23591526

  10. Method calibration of the model 13145 infrared target projectors

    NASA Astrophysics Data System (ADS)

    Huang, Jianxia; Gao, Yuan; Han, Ying

    2014-11-01

    The SBIR Model 13145 Infrared Target Projectors ( The following abbreviation Evaluation Unit ) used for characterizing the performances of infrared imaging system. Test items: SiTF, MTF, NETD, MRTD, MDTD, NPS. Infrared target projectors includes two area blackbodies, a 12 position target wheel, all reflective collimator. It provide high spatial frequency differential targets, Precision differential targets imaged by infrared imaging system. And by photoelectricity convert on simulate signal or digital signal. Applications software (IR Windows TM 2001) evaluate characterizing the performances of infrared imaging system. With regards to as a whole calibration, first differently calibration for distributed component , According to calibration specification for area blackbody to calibration area blackbody, by means of to amend error factor to calibration of all reflective collimator, radiance calibration of an infrared target projectors using the SR5000 spectral radiometer, and to analyze systematic error. With regards to as parameter of infrared imaging system, need to integrate evaluation method. According to regulation with GJB2340-1995 General specification for military thermal imaging sets - testing parameters of infrared imaging system, the results compare with results from Optical Calibration Testing Laboratory . As a goal to real calibration performances of the Evaluation Unit.

  11. Calibration of solar cells' photoelectric properties and related uncertainty analysis

    NASA Astrophysics Data System (ADS)

    Meng, Haifeng; Xiong, Limin; He, Yingwei; Zhang, Junchao; Tian, Wei; Liu, Dingpu; Zhang, Jieyu; Xie, Linlin; Lei, Liu

    2014-07-01

    Solar cells' photoelectric properties calibration, i.e., current-voltage (I-V) characteristics is critical for both fundamental research and photovoltaic production line. This paper will present calibration of solar cells' I-V characteristics by a substitution method under simulate light source. Considering the calibration uncertainty and measurement accuracy, reliable measurement procedures developed in NIM with uncertainty analysis are also demonstrated. By controlling the influencing factors, relative expended combined uncertainty (Urel) of 2.1% (Isc), 1.0% (Voc) and 3.1% (Pmax) was concluded here, with a coverage factor k = 2. The measurement system meets all requirements of IEC 60904-1 and IEC 60904-9, and it has been applied to amounts of solar cells' I-V curves calibration for research institutes as well as industrial plants, which solved the problem of domestic metrology technology shortage in photovoltaic field.

  12. High coverage needle/syringe programs for people who inject drugs in low and middle income countries: a systematic review

    PubMed Central

    2013-01-01

    Background Persons who inject drugs (PWID) are at an elevated risk for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection. In many high-income countries, needle and syringe exchange programs (NSP) have been associated with reductions in blood-borne infections. However, we do not have a good understanding of the effectiveness of NSP in low/middle-income and transitional-economy countries. Methods A systematic literature review based on PRISMA guidelines was utilized to collect primary study data on coverage of NSP programs and changes in HIV and HCV infection over time among PWID in low-and middle-income and transitional countries (LMICs). Included studies reported laboratory measures of either HIV or HCV and at least 50% coverage of the local injecting population (through direct use or through secondary exchange). We also included national reports on newly reported HIV cases for countries that had national level data for PWID in conjunction with NSP scale-up and implementation. Results Studies of 11 NSPs with high-coverage from Bangladesh, Brazil, China, Estonia, Iran, Lithuania, Taiwan, Thailand and Vietnam were included in the review. In five studies HIV prevalence decreased (range ?3% to ?15%) and in three studies HCV prevalence decreased (range ?4.2% to ?10.2%). In two studies HIV prevalence increased (range +5.6% to +14.8%). HCV incidence remained stable in one study. Of the four national reports of newly reported HIV cases, three reported decreases during NSP expansion, ranging from ?30% to ?93.3%, while one national report documented an increase in cases (+37.6%). Estimated incidence among new injectors decreased in three studies, with reductions ranging from ?11/100 person years at risk to ?16/100 person years at risk. Conclusions While not fully consistent, the data generally support the effectiveness of NSP in reducing HIV and HCV infection in low/middle-income and transitional-economy countries. If high coverage is achieved, NSP appear to be as effective in LMICs as in high-income countries. Additional monitoring and evaluation research is needed for NSPs where reductions in HIV/HCV infection among PWID are not occurring in order to identify and correct contributing problems. PMID:23332005

  13. Systematic review research on needle/syringe programs and opiate substitution programs in low- and middle-income countries.

    PubMed

    Jarlais, Don Des

    2013-12-01

    Persons who inject drugs (PWID) are at an elevated risk for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection. In many high-income countries, needle and syringe exchange programs (NSPs) have been associated with reductions in blood-borne infections. However, we do not have a good understanding of the effectiveness of NSP in low/middle-income and transitional-economy countries. A systematic literature review based on PRISMA guidelines was utilized to collect primary study data on coverage of NSP programs and changes in HIV and HCV infection over time among PWID in low- and middle-income and transitional countries (LMICs). Included studies reported laboratory measures of either HIV or HCV and at least 50% coverage of the local injecting population (through direct use or through secondary exchange). We also included national reports on newly reported HIV cases for countries that had national level data for PWID in conjunction with NSP scale-up and implementation. Studies of 11 NSPs with high-coverage from Bangladesh, Brazil, China, Estonia, Iran, Lithuania, Taiwan, Thailand, and Vietnam were included in the review. In five studies, HIV prevalence decreased (range -3% to -15%) and in three studies HCV prevalence decreased (range -4.2% to -10.2%). In two studies, HIV prevalence increased (range +5.6% to +14.8%). HCV incidence remained stable in one study. Of the four national reports of newly reported HIV cases, three reported decreases during NSP expansion, ranging from -30% to -93.3%, whereas one national report documented an increase in cases (+37.6%). Estimated incidence among new injectors decreased in three studies, with reductions ranging from -11/100 person years at risk to -16/100 person years at risk. While not fully consistent, the data generally support the effectiveness of NSP in reducing HIV and HCV infection in low/middle-income and transitional-economy countries. If high coverage is achieved, NSP appear to be as effective in LMICs as in high-income countries. Additional monitoring and evaluation research is needed for NSPs where reductions in HIV/HCV infection among PWID are not occurring in order to identify and correct contributing problems. PMID:25267887

  14. ALTEA: The instrument calibration

    NASA Astrophysics Data System (ADS)

    Zaconte, V.; Belli, F.; Bidoli, V.; Casolino, M.; di Fino, L.; Narici, L.; Picozza, P.; Rinaldi, A.; Sannita, W. G.; Finetti, N.; Nurzia, G.; Rantucci, E.; Scrimaglio, R.; Segreto, E.; Schardt, D.

    2008-05-01

    The ALTEA program is an international and multi-disciplinary project aimed at studying particle radiation in space environment and its effects on astronauts’ brain functions, as the anomalous perception of light flashes first reported during Apollo missions. The ALTEA space facility includes a 6-silicon telescopes particle detector, and is onboard the International Space Station (ISS) since July 2006. In this paper, the detector calibration at the heavy-ion synchrotron SIS18 at GSI Darmstadt will be presented and compared to the Geant 3 Monte Carlo simulation. Finally, the results of a neural network analysis that was used for ion discrimination on fragmentation data will also be presented.

  15. A self-calibrating optomechanical force sensor with femtonewton resolution

    NASA Astrophysics Data System (ADS)

    Melcher, John; Stirling, Julian; Cervantes, Felipe Guzmán; Pratt, Jon R.; Shaw, Gordon A.

    2014-12-01

    We report the development of an ultrasensitive optomechanical sensor designed to improve the accuracy and precision of force measurements with atomic force microscopy. The sensors reach quality factors of 4.3 × 106 and force resolution on the femtonewton scale at room temperature. Self-calibration of the sensor is accomplished using radiation pressure to create a reference force. Self-calibration enables in situ calibration of the sensor in extreme environments, such as cryogenic ultra-high vacuum. The senor technology presents a viable route to force measurements at the atomic scale with uncertainties below the percent level.

  16. The MISR Calibration Program

    NASA Technical Reports Server (NTRS)

    Bruegge, Carol J.; Diner, David J.; Duval, Valerie G.

    1996-01-01

    The Multiangle Imaging SpectroRadiometer (MISR) is currently under development for NASA's Earth Observing System. The instrument consists of nine pushbroom cameras, each with four spectral bands in the visible and near-infrared. The cameras point in different view directions to provide measurements from nadir to highly oblique view angles in the along-track plane. Multiple view-angle observations provide a unique resource for studies of clouds, aerosols, and the surface. MISR is built to challenging radiometric and geometric performance specifications. Radiometric accuracy, for example, must be within +/- 3%/ 1 sigma, and polarization insensitivity must be better than +/- 1 %. An onboard calibrator (OBC) provides monthly updates to the instrument gain coefficients. Spectralon diffuse panels are used within the OBC to provide a uniform target for the cameras to view. The absolute radiometric scale is established both preflight and in orbit through the use of detector standards. During the mission, ground data processing to accomplish radiometric calibration, geometric rectification and registration of the nine view-angle imagery, and geophysical retrievals will proceed in an automated fashion. A global dataset is produced every 9 days. This paper details the preflight characterization of the MISR instrument, the design of the OBC, and the radiance product processing.

  17. Piezoelectric trace vapor calibrator

    NASA Astrophysics Data System (ADS)

    Verkouteren, R. Michael; Gillen, Greg; Taylor, David W.

    2006-08-01

    The design and performance of a vapor generator for calibration and testing of trace chemical sensors are described. The device utilizes piezoelectric ink-jet nozzles to dispense and vaporize precisely known amounts of analyte solutions as monodisperse droplets onto a hot ceramic surface, where the generated vapors are mixed with air before exiting the device. Injected droplets are monitored by microscope with strobed illumination, and the reproducibility of droplet volumes is optimized by adjustment of piezoelectric wave form parameters. Complete vaporization of the droplets occurs only across a 10°C window within the transition boiling regime of the solvent, and the minimum and maximum rates of trace analyte that may be injected and evaporated are determined by thermodynamic principles and empirical observations of droplet formation and stability. By varying solution concentrations, droplet injection rates, air flow, and the number of active nozzles, the system is designed to deliver—on demand—continuous vapor concentrations across more than six orders of magnitude (nominally 290fg/lto1.05?g/l). Vapor pulses containing femtogram to microgram quantities of analyte may also be generated. Calibrated ranges of three explosive vapors at ng/l levels were generated by the device and directly measured by ion mobility spectrometry (IMS). These data demonstrate expected linear trends within the limited working range of the IMS detector and also exhibit subtle nonlinear behavior from the IMS measurement process.

  18. NASA Metrology and Calibration, 1980

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The proceedings of the fourth annual NASA Metrology and Calibration Workshop are presented. This workshop covered (1) review and assessment of NASA metrology and calibration activities by NASA Headquarters, (2) results of audits by the Office of Inspector General, (3) review of a proposed NASA Equipment Management System, (4) current and planned field center activities, (5) National Bureau of Standards (NBS) calibration services for NASA, (6) review of NBS's Precision Measurement and Test Equipment Project activities, (7) NASA instrument loan pool operations at two centers, (8) mobile cart calibration systems at two centers, (9) calibration intervals and decals, (10) NASA Calibration Capabilities Catalog, and (11) development of plans and objectives for FY 1981. Several papers in this proceedings are slide presentations only.

  19. An Overview of MODIS Calibration and Characterization

    NASA Technical Reports Server (NTRS)

    Xiong, X.; Barnes, W.

    2004-01-01

    The MODerate Resolution Imaging Spectroradiometer (MODIS) is one of the key instruments for the NASA s Earth Observing System (EOS). It is currently operating on both EOS Terra and Aqua satellites. The MODIS is a major advance over its heritage sensors in terms of its spectral, spatial, and temporal resolutions with frequent global observations and a broad range of science applications. There are 20 reflective solar bands (RSB) with center wavelengths ranging from 0.41 to 2.l microns and 16 thermal emissive bands (TEB) from 3.7 to 14.4 microns. The absolute radiometric accuracy requirements (lsigma) at the typical spectral radiance levels are plus or minus 2% for the RSB reflectance factors and plus or minus 5% for the RSB radiance products. With few exceptions, the TEB requirements are plus or minus 1%. To verify that the instruments met their specified design requirements both Terra and Aqua MODIS underwent extensive pre-launch calibration and characterization at various levels, including system-level thermal vacuum testing. On-orbit calibration and characterization are performed by the on-board calibrators: a solar diffuser (SD) and a solar diffuser stability monitor (SDSM), a V-groove flat panel blackbody (BB), and a spectro-radiometric calibration assembly (SRCA). In this paper, we present an overview of MODIS calibration and characterization activities, methodologies, and lessons learned from pre-launch testing and on-orbit operations. Key issues to be discussed include our on-orbit efforts of monitoring detectors noise characterization, tracking solar diffuser and optics degradation, and updating sensor s response versus scan-angle. The MODIS experience has provided invaluable lessons that are being used in designing and testing the Visible Infrared Imaging Radiometer Suite (VIIRS), a direct follow-on to the MODIS that will be flown on the National Polar-Orbit Operational Environmental Satellite System (NPOESS) missions.

  20. Hot-wire calibration in subsonic/transonic flow regimes

    NASA Technical Reports Server (NTRS)

    Nagabushana, K. A.; Ash, Robert L.

    1995-01-01

    A different approach for calibrating hot-wires, which simplifies the calibration procedure and reduces the tunnel run-time by an order of magnitude was sought. In general, it is accepted that the directly measurable quantities in any flow are velocity, density, and total temperature. Very few facilities have the capability of varying the total temperature over an adequate range. However, if the overheat temperature parameter, a(sub w), is used to calibrate the hot-wire then the directly measurable quantity, voltage, will be a function of the flow variables and the overheat parameter i.e., E = f(u,p,a(sub w), T(sub w)) where a(sub w) will contain the needed total temperature information. In this report, various methods of evaluating sensitivities with different dependent and independent variables to calibrate a 3-Wire hot-wire probe using a constant temperature anemometer (CTA) in subsonic/transonic flow regimes is presented. The advantage of using a(sub w) as the independent variable instead of total temperature, t(sub o), or overheat temperature parameter, tau, is that while running a calibration test it is not necessary to know the recovery factor, the coefficients in a wire resistance to temperature relationship for a given probe. It was deduced that the method employing the relationship E = f (u,p,a(sub w)) should result in the most accurate calibration of hot wire probes. Any other method would require additional measurements. Also this method will allow calibration and determination of accurate temperature fluctuation information even in atmospheric wind tunnels where there is no ability to obtain any temperature sensitivity information at present. This technique greatly simplifies the calibration process for hot-wires, provides the required calibration information needed in obtaining temperature fluctuations, and reduces both the tunnel run-time and the test matrix required to calibrate hotwires. Some of the results using the above techniques are presented in an appendix.

  1. Optimized extraction method for LC-MS determination of bisphenol A, melamine and di(2-ethylhexyl) phthalate in selected soft drinks, syringes, and milk powder.

    PubMed

    Khedr, Alaa

    2013-07-01

    Described below is an optimized solid-phase extraction method (SPE) for the simultaneous determination of three hazardous plastic additives. Two high-performance liquid chromatographic-electrospray ionization-mass spectrometric (HPLC-ESI-MS) methods were developed and validated to estimate the melamine (MEL), bis(2-ethylhexyl) phthalate (DEHP), and bisphenol A (BPA) contents in drinking water, syringes, soft drinks, and dry milk powder. One extraction procedure optimally recovered all three substances from the different matrices. Two extraction columns were combined and included a silica gel LiChroprep RP-2 column (20:1, g/g, top column) and a Sep-Pak with a C18 column (500mg, bottom column). The analytical column was an Agilent Eclipse XDB-C8 column, 4.6mm×150mm, 5?m, maintained at 50±2°C. MEL and DEHP were monitored by positive triple quad mass spectrometry (TQ-MS) using an acidic mobile phase, while BPA was monitored by negative TQ-MS using a mobile phase containing a 0.05% ammonia solution. The general linear range of the three compounds ranged from 12 to 1000pg/?L in the injected solution (25?L). The average extraction recoveries were within the range of 83.0-102.5%. Relatively high concentrations of BPA and DEHP were found in the milk powder and sterile syringes. PMID:23727873

  2. The use of precision glass syringes and a noncontact microsolenoid dispenser for the production of high-throughput low-density arrays.

    PubMed

    Azarani, Arezou

    2004-01-01

    The advantages of using nondisposable precision glass syringes in automated high-throughput microdispensers and a single-channel noncontact microsolenoid dispenser in creating highly uniform and reproducible protein, nucleic acid, and organic compound array filters, slides, and plates are described. Using a HydraPlus-One system, protein solutions of up to 100 mg/mL (in 100 nL) can be spotted onto slides and plates at a speed of 0.6 s per spot. Using the Hydra microdispenser and Tango liquid handling system, as little as 100 nL of polymerase chain reaction (PCR)-amplified human cancer-related genes, housekeeping genes, and protein solutions can be spotted onto nylon membranes, coated slides, or plates. Using these microdispensers equipped with syringes, up to 6144 uniform and reproducible spots per membrane and up to 1000 spots per slide, with a precision variation of less than 10%, were printed at a speed of as fast as 2.5 min per membrane. PMID:15020787

  3. Improvements in dissemination of spectral irradiance calibrations

    NASA Astrophysics Data System (ADS)

    Kärhä, P.; Ylianttila, L.; Jokela, K.; Ikonen, E.

    2003-04-01

    Solar UV measurements have reached a level where uncertainties and discrepancies of standard lamps used for calibration of the spectroradiometers are already limiting factors in the measurements. Lamps purchased from different national standards laboratories often show discrepancies higher than the stated uncertainties when measured in solar UV intercomparison campaigns. One major source for the deviations between the lamps is changes of the lamp irradiance in transportation. Even if hand-carried, the lamps may be damaged by thermal or mechanical shocks. Short-circuiting of the coils causes spectrally dependent decrease of the spectral irradiance values. This effect can be detected, but not quantified, by monitoring the voltage across the lamp terminals. However, this monitoring does not reveal changes caused by bending of the filaments. At the Helsinki University of Technology (HUT), we have developed a portable primary standard of spectral irradiance based on characterised filter radiometers. The standard consists of a filter radiometer with 14 interchangeable narrow-band interference filters for the wavelength region 290 - 900 nm. The filter radiometer is packed in a flight case that allows its transportation to solar UV measurement sites. Thus, the use of the filter radiometer eliminates completely the need to transport lamps. The method has been tested in direct intercomparisons with PTB (Germany), NPL (UK) and NIST (USA). The results of the intercomparisons clearly verify the calculated uncertainties (2 sigma) that range between 2.7% and 1.5% in the solar UV region of 290 - 380 nm. The filter radiometer can also be used to calibrate a solar UV calibrator that has been developed in a collaboration project between HUT and STUK. This calibrator utilises a 1-kW DXW-type lamp that has been enclosed in robust aluminium housing. The lamp is monitored with two narrow-band UV filter radiometers. The calibrator can be assembled on top of any spectroradiometer by using interchangeable adapter plates. The method has been tested in intercomparisons at measurement sites of STUK and Finnish Meteorological Institute (FMI). The tests indicate that the use of the calibrator can improve measurement uncertainties of Brewer and Bentham spectroradiometers. Calibrations can be performed outside even in the middle of the Finnish winter.

  4. Laboratory calibration of field reflectance panels

    NASA Technical Reports Server (NTRS)

    Biggar, S. F.; Labed, J.; Santer, R. P.; Slater, P. N.; Jackson, R. D.

    1988-01-01

    A method used for calibrating field reflectance panels in the visible and shortwave infrared wavelength range is described. The directional reflectance factor of painted barium sulfate (BaSO4) panels is determined. The reference for this method is the hemispherical reflectance of pressed polytetrafluoroethylene (halon) powder prepared according to National Bureau of Standards (NBS) directions. The panels and a radiometer are mounted on rotation stages to measure the reflectance factor at different incidence and view angles. The sensor can be any laboratory or field filter radiometer small enough to mount on the apparatus. The method is used to measure the reflectance factors of halon and BaSO4 panels between 0.45 and 0.85 micrometers. These reflectance factors are compared to those measured by a field apparatus. The results agree to within 0.013 in reflectance at incidence angles between 15 and 75 degrees.

  5. MODIS Solar Calibration Simulation Assisted Refinement

    NASA Technical Reports Server (NTRS)

    Waluschka, Eugene; Xiaoxiong, Xiong; Guenther, Bruce; Barnes, William; Moyer, David; Salomonson, Vincent V.

    2004-01-01

    A detailed optical radiometric model has been created of the MODIS instruments solar calibration process. This model takes into account the orientation and distance of the spacecraft with respect to the sun, the correlated motions of the scan mirror and the sun, all of the optical elements, the detector locations on the visible and near IR focal planes, the solar diffuser and the attenuation screen with all of its hundreds of pinholes. An efficient computational scheme, takes into account all of these factors and has produced results which reproduce the observed time dependent intensity variations on the two focal planes with considerable fidelity. This agreement between predictions and observations, has given insight to the causes of some small time dependent variations and how to incorporate them into the overall calibration scheme. The radiometric model is described and modeled and actual measurements are presented and compared.

  6. Inspection system calibration methods

    DOEpatents

    Deason, Vance A.; Telschow, Kenneth L.

    2004-12-28

    An inspection system calibration method includes producing two sideband signals of a first wavefront; interfering the two sideband signals in a photorefractive material, producing an output signal therefrom having a frequency and a magnitude; and producing a phase modulated operational signal having a frequency different from the output signal frequency, a magnitude, and a phase modulation amplitude. The method includes determining a ratio of the operational signal magnitude to the output signal magnitude, determining a ratio of a 1st order Bessel function of the operational signal phase modulation amplitude to a 0th order Bessel function of the operational signal phase modulation amplitude, and comparing the magnitude ratio to the Bessel function ratio.

  7. Atmospheric optical calibration system

    DOEpatents

    Hulstrom, R.L.; Cannon, T.W.

    1988-10-25

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions. 7 figs.

  8. Atmospheric optical calibration system

    DOEpatents

    Hulstrom, Roland L. (Bloomfield, CO); Cannon, Theodore W. (Golden, CO)

    1988-01-01

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions.

  9. RX130 Robot Calibration

    NASA Astrophysics Data System (ADS)

    Fugal, Mario

    2012-10-01

    In order to create precision magnets for an experiment at Oak Ridge National Laboratory, a new reverse engineering method has been proposed that uses the magnetic scalar potential to solve for the currents necessary to produce the desired field. To make the magnet it is proposed to use a copper coated G10 form, upon which a drill, mounted on a robotic arm, will carve wires. The accuracy required in the manufacturing of the wires exceeds nominal robot capabilities. However, due to the rigidity as well as the precision servo motor and harmonic gear drivers, there are robots capable of meeting this requirement with proper calibration. Improving the accuracy of an RX130 to be within 35 microns (the accuracy necessary of the wires) is the goal of this project. Using feedback from a displacement sensor, or camera and inverse kinematics it is possible to achieve this accuracy.

  10. A new solid phase microextraction method using organic ligand in micropipette tip syringe system packed with modified carbon cloth for preconcentration of cadmium in drinking water and blood samples of kidney failure patients

    NASA Astrophysics Data System (ADS)

    Panhwar, Abdul Haleem; Kazi, Tasneem Gul; Afridi, Hassan Imran; Arain, Salma Aslam; Naeemullah; Brahman, Kapil Dev; Arain, Mariam Shahzadi

    2015-03-01

    A simple and efficient miniaturized solid phase microextraction (M-SP?E) in a syringe system was developed for preconcentration of cadmium (Cd) in environmental and biological samples, followed by flame atomic absorption technique. The syringe system contains the micropipette tip packed with activated carbon cloth, coated with modified magnetic nanoparticles of iron oxide Triton X114 (ACC-NPs). Scanning electron microscopy and energy dispersive spectroscopy used for characterization of the size, morphology and elemental composition of ACC-NPs. The sample solution treated with a complexing reagent 8-hydroxyqunilone (8-HQ), and drawn into the syringe, filled with ACC-MNPs and dispensed manually for 2-10 drawing/discharging cycles. The analyte retained on ACC-NPs in micropipette tip-syringe system were then eluted with different volume of 1.5 mol L-1 HCl by 1-5 drawing/discharging cycles. The syringe system directly couple with FAAS for analysis. The influence of different variables on the extraction efficiency of Cd, including adsorbent dosage, pH, sample volume, eluent volume and drawing/discharging cycles of syringe system were optimized. At optimized extraction conditions, the method showed good linearity in the range of 5-250 ?g L-1, with a limit of detection 0.15 ?g L-1. Repeatability of the extraction (%RSD) was <5%, n = 5. The validity and accuracy of the method was checked by the certified reference materials. The proposed method was successfully applied for the determination of Cd in different drinking water and biological samples of kidney failure patients and healthy controls.

  11. TOD to TTP calibration

    NASA Astrophysics Data System (ADS)

    Bijl, Piet; Reynolds, Joseph P.; Vos, Wouter K.; Hogervorst, Maarten A.; Fanning, Jonathan D.

    2011-05-01

    The TTP (Targeting Task Performance) metric, developed at NVESD, is the current standard US Army model to predict EO/IR Target Acquisition performance. This model however does not have a corresponding lab or field test to empirically assess the performance of a camera system. The TOD (Triangle Orientation Discrimination) method, developed at TNO in The Netherlands, provides such a measurement. In this study, we make a direct comparison between TOD performance for a range of sensors and the extensive historical US observer performance database built to develop and calibrate the TTP metric. The US perception data were collected doing an identification task by military personnel on a standard 12 target, 12 aspect tactical vehicle image set that was processed through simulated sensors for which the most fundamental sensor parameters such as blur, sampling, spatial and temporal noise were varied. In the present study, we measured TOD sensor performance using exactly the same sensors processing a set of TOD triangle test patterns. The study shows that good overall agreement is obtained when the ratio between target characteristic size and TOD test pattern size at threshold equals 6.3. Note that this number is purely based on empirical data without any intermediate modeling. The calibration of the TOD to the TTP is highly beneficial to the sensor modeling and testing community for a variety of reasons. These include: i) a connection between requirement specification and acceptance testing, and ii) a very efficient method to quickly validate or extend the TTP range prediction model to new systems and tasks.

  12. Update of the Photometric Calibration of the LASCO-C2 Coronagraph Using Stars

    NASA Astrophysics Data System (ADS)

    Colaninno, Robin; Howard, Russell

    2015-04-01

    We present an update to the photometric calibration of the LASCO-C2 coronagraph onboard the SOHO spacecraft. We obtained the new calibration using data from the beginning of the mission in 1996 until 2013. We re-examined the LASCO-C2 photometric calibration by comparing the past three calibrations and the present calibration with the goal of validating an in-flight calibration. We find a photometric calibration factor (PCF) that is very similar to the factor recently published in Gardès, Lamy, and Llebaria (Solar Phys. 283, 667, 2013), which calculated a calibration between 1996 and 2009. The average of our PCF between 1999 and 2009 is the same, within our margin of error, as the average given by Gardès, Lamy, and Llebaria (Solar Phys. 283, 667, 2013) during the same time period. However, we find a different evolution of the calibration over the lifetime of the LASCO-C2 instrument compared with past results. We find that the sensitivity of the instrument is decreasing by a constant 0.20 [±0.03] % per year. We also find no significant difference in the signal degradation before and after the SOHO interruption. We discuss the effects of this new PCF on the calibrated data set and the potential impact on scientific results derived from the previous calibration.

  13. Update of the Photometric Calibration of the LASCO-C2 Coronagraph Using Stars

    NASA Astrophysics Data System (ADS)

    Colaninno, R. C.; Howard, R. A.

    2015-03-01

    We present an update to the photometric calibration of the LASCO-C2 coronagraph onboard the SOHO spacecraft. We obtained the new calibration using data from the beginning of the mission in 1996 until 2013. We re-examined the LASCO-C2 photometric calibration by comparing the past three calibrations and the present calibration with the goal of validating an in-flight calibration. We find a photometric calibration factor (PCF) that is very similar to the factor recently published in Gardès, Lamy, and Llebaria ( Solar Phys. 283, 667, 2013), which calculated a calibration between 1996 and 2009. The average of our PCF between 1999 and 2009 is the same, within our margin of error, as the average given by Gardès, Lamy, and Llebaria ( Solar Phys. 283, 667, 2013) during the same time period. However, we find a different evolution of the calibration over the lifetime of the LASCO-C2 instrument compared with past results. We find that the sensitivity of the instrument is decreasing by a constant 0.20 [±0.03] % per year. We also find no significant difference in the signal degradation before and after the SOHO interruption. We discuss the effects of this new PCF on the calibrated data set and the potential impact on scientific results derived from the previous calibration.

  14. Drug-Related Arrest Rates and Spatial Access to Syringe Exchange Programs in New York City Health Districts: Combined Effects on the Risk of Injection-Related Infections among Injectors

    PubMed Central

    Jarlais, Don C Des; Tempalski, Barbara; Bossak, Brian H; Ross, Zev; Friedman, Samuel R

    2011-01-01

    Drug-related law enforcement activities may undermine the protective effects of syringe exchange programs (SEPs) on local injectors’ risk of injection-related infections. We explored the spatial overlap of drug-related arrest rates and access to SEPs over time (1995-2006) in New York City health districts, and used multilevel models to investigate the relationship of these two district-level exposures to the odds of injecting with an unsterile syringe. Districts with better SEP access had higher arrest rates, and arrest rates undermined SEPs’ protective relationship with unsterile injecting. Drug-related enforcement strategies targeting drug users should be de-emphasized in areas surrounding SEPs. PMID:22047790

  15. Calibration of a Horizontal Sundial

    ERIC Educational Resources Information Center

    Rovsek, Barbara

    2010-01-01

    This paper describes how a horizontal sundial can be calibrated in a classroom without using the nontrivial equations of projective geometry. If one understands how a simple equatorial sundial works, one will also understand the procedure of calibrating a horizontal (or "garden," as it is also called) sundial.

  16. Calibration of Hubble Space Telescope

    E-print Network

    Jefferys, William

    Calibration of Hubble Space Telescope Guidance Sensors: Application of Seminal Ideas of Eichhorn William H. Je#erys 11, Abstract calibration Space Telescope Guidance Sensors (FGS) a challenges. no su's on solving important astrometric problem. Introduction Hubble Telescope Guidance Sensors (FGS) designed

  17. INERTIAL MEASUREMENT UNIT CALIBRATION PLATFORM

    E-print Network

    Williams II, Robert L.

    calibration and alignment of a six degrees-of-freedom (dof) IMU for land vehicle navigation applications. By contrast, the current article presents a platform manipulator for off-line calibration of three Athens, OH 45701 Final Manuscript Journal of Robotic Systems June, 2000 Keywords: Platform Manipulator

  18. GOSAT calibration and validation plan

    NASA Astrophysics Data System (ADS)

    Shiomi, Kei; Morino, Isamu; Uchino, Osamu; Yokota, Tatsuya; Inoue, Gen

    Greenhouse gases Observing SATellite (GOSAT) is aimed at observing the greenhouse gases, such as CO2 and CH4, from space. GOSAT carries Thermal And Near infrared Sensor for carbon Observation (TANSO). TANSO is composed of 2 instruments, Fourier Transform Spectrometer (FTS) for measuring greenhouse gases absorption spectra, and Cloud and Aerosol Imager (CAI) for cloud detection and the correction of cirrus and aerosol interference within the FTS field of view. FTS observes at wavelengths of shortwave infrared and thermal infrared with same optics. The GOSAT program is collaborated among Japan Aerospace Exploration Agency (JAXA), Ministry of the Environment (MOE) and National Institute for Environmental Studies (NIES). JAXA is responsible for development of satellite and sensors, launching, data receiving, L1 processing and calibration. MOE and NIES are responsible for development of L2 and higher products and validation. Calibration of GOSAT L1 products is conducted by on-board calibration and vicarious calibration for radiometry, geometry, spectral quality and image quality. Vicarious calibration is mainly implemented by using other well-calibrated satellite data and reliable meteorological database such as surface reflectance spectra and sea surface temperature. Validation of GOSAT is mainly conducted by ground-based FTS measurements at the same wavelengths and aircraft in-situ measurements of column amount and profile. The cross calibration and validation with NASA OCO at simultaneous observations are effective methods for direct comparisons of spectral radiance and XCO2. This presentation shows the current status of calibration and validation plan of GOSAT.

  19. Algorithms for coplanar camera calibration

    Microsoft Academic Search

    Chanchal Chatterjee; Vwani P. Roychowdhury

    2000-01-01

    Coplanar camera calibration is the process of de- termining the extrinsic and intrinsic camera parameters from a given set of image and world points, when the world points lie on a two-dimensional plane. Noncoplanar cali- bration, on the other hand, involves world points that do not lie on a plane. While optimal solutions for both the camera- calibration procedures can

  20. Antenna Position Calibration Melvyn Wright

    E-print Network

    antenna positions. SELFCAL can include known source structure in the quasars. The baseline observationsAntenna Position Calibration Melvyn Wright Radio Astronomy laboratory, University of California, Berkeley, CA, 94720 ABSTRACT This memo summarizes the antenna position calibration used at Hat Creek

  1. Calibration of a Horizontal Sundial

    NASA Astrophysics Data System (ADS)

    Rovšek, Barbara

    2010-09-01

    This paper describes how a horizontal sundial can be calibrated in a classroom without using the nontrivial equations of projective geometry. If one understands how a simple equatorial sundial works, one will also understand the procedure of calibrating a horizontal (or "garden," as it is also called) sundial.

  2. Effects of switch leakages upon Nimbus-7 SMMR calibration

    NASA Technical Reports Server (NTRS)

    Han, Daesoo; Kim, Seung T.

    1988-01-01

    A calibration model for the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) is studied. This model not only removes major drawbacks of the current calibration model but also helps us understand the performance degradation of the aging instrument. The current Nimbus-7 SMMR calibration algorithm was derived without considering the interference effect between the two orthogonally polarized signals merging at a ferrite polarization selector switch. The resulting calibrated brightness temperatures, considered as a function of scan angle phi, are not symmetric around phi=0. However, neither the origin of the asymmetry nor the manner in which the two orthogonal components are mixed is fully understood. The proposed calibration model incorporates all the leakage factors associated with the ferrite switches along the signal paths. The resulting calibration equations clarify how the orthogonal components of surface brightness are coupled at radiometers. As a consequence, the origin of the asymmetry is clearly identified and explained. In addition, the feasibility of absolute calibration using in-orbit data is discussed.

  3. Effects of switch leakages upon Nimbus-7 SMMR calibration

    NASA Technical Reports Server (NTRS)

    Han, Daesoo; Kim, Seung T.

    1988-01-01

    A calibration model for the Nimbus 7 Scanning Multichannel Microwave Radiometer (SMMR) is studied. This model not only removes major drawbacks of the current calibration model but also helps in the understanding of the performance degradation of the aging instrument. The current Nimbus 7 SMMR calibration algorithm was derived without considering the interference effect between the two orthogonally polarized signals merging at a ferrite polarization selector switch. The resulting calibrated brightness temperatures, considered as a function of scan angle, are not symmetric around scan angle = 0. However, neither the origin of the asymmetry nor the manner in which the two orthogonal components are mixed has been fully understood. The new calibration model proposed incorporates all the leakage factors associated with the ferrite switches along the signal paths. The resulting calibration equations clarify how the orthogonal components of surface brightness are coupled at radiometers. As a consequence, the origin of the asymmetry is clearly identified and explained. In addition, the feasibility of absolute calibration using in-orbit data is discussed.

  4. ENVISAT-1 MWR: calibration targets and preflight calibration

    NASA Astrophysics Data System (ADS)

    Atkinson, Nigel C.; Bombaci, Ornella; L'Abbate, Michele; Ricketts, Marion

    1998-12-01

    ENVISAT Microwave Radiometer (MWR) is an instrument designed and developed as part of the Envisat-1 satellite scientific payload, with Alenia Aerospazio engaged in the phase C-D as instrument Prime Contractor, leading an industrial consortium of European and American companies. The Flight Model of the Instrument was delivered to ESA at the end of July 1997, after successful completion of design, test and calibration activities. An Engineering Model of the instrument was also developed and completed in March 1997. The MWR output products are of prime importance for wind/wave products of the Radar Altimeter (RA-2) Instrument, part of the Envisat-1 payload, providing correction of atmospheric propagation data. The products are also useful for direct evaluation of brightness temperature in order to characterize polar ice, land surface properties and sea surface temperature. In order to achieve the required accuracy and sensitivity performance, an in- flight two-point calibration concept is adopted, with hot and cold calibration reference points for each frequency channel. Periodically the measurements of earth scene radiation are interrupted to allow the measurement of an on-board calibration load and of the deep cold space. The overall ground calibration tasks were performed through an iterative sequence of measurement and relevant model corrections, with an extensive instrument calibration in a thermal-vacuum environment, to derive the final radiometer model coefficients and to verify its performance in the expected in-flight environment. To achieve the required instrument calibration accuracy, extremely accurate blackbody target sources were required, in order to simulate the Earth scene and the deep space (for cold calibration), as seen by the radiometer during its in-flight mission. The definition, development and characterization of such blackbody targets were key aspects to achieving the required stimulus accuracy for proper calibration of the instrument. These tasks were jointly performed by the UK Meteorological Office (UKMO) and Alenia Aerospazio, and lead to the final calibration of the instrument with successful results. Within this paper an overview of the instrument calibration will be given; emphasis will be on the trade-offs and design requirements derived for the Calibration Targets, on their design and calibration, and finally on the achieved results and instrument performance.

  5. VizieR Online Data Catalog: LOFAR long baselines at 140MHz Calibrators (Moldon+, 2015)

    NASA Astrophysics Data System (ADS)

    Moldon, J.; Deller, A. T.; Wucknitz, O.; Jackson, N.; Drabent, A.; Carozzi, T.; Conway, J.; Kapinska, A. D.; McKean, J. P.; Morabito, L.; Varenius, E.; Zarka, P.; Anderson, J.; Asgekar, A.; Avruch, I. M.; Bell, M. E.; Bentum, M. J.; Bernardi, G.; Best, P.; Birzan, L.; Bregman, J.; Breitling, F.; Broderick, J. W.; Bruggen, M.; Butcher, H. R.; Carbone, D.; Ciardi, B.; de Gasperin, F.; de Geus, E.; Duscha, S.; Eislooffel, J.; Engels, D.; Falcke, H.; Fallows, R. A.; Fender, R.; Ferrari, C.; Frieswijk, W.; Garrett, M. A.; Griessmeier, J.; Gunst, A. W.; Hamaker, J. P.; Hassall, T. E.; Heald, G.; Hoeft, M.; Juette, E.; Karastergiou, A.; Kondratiev, V. I.; Kramer, M.; Kuniyoshi, M.; Kuper, G.; Maat, P.; Mann, G.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Morganti, R.; Munk, H.; Norden, M. J.; Offringa, A. R.; Orru, E.; Paas, H.; Pandey-Pommier, M.; Pizzo, R.; Polatidis, A. G.; Reich, W.; Roottgering, H.; Rowlinson, A.; Scaife, A. M. M.; Schwarz, D.; Sluman, J.; Smirnov, O.; Stappers, B. W.; Steinmetz, M.; Tagger, M.; Tang, Y.; Tasse, C.; Thoudam, S.; Toribio, M. C.; Verme! ulen R., Vocks C., van Weeren R.J., White S., Wise M.W., Yatawatta S., Zensus A.

    2014-11-01

    We observed 630 sources with the LOFAR international baselines to determine if they are compact enough to be delay calibrators. We used information in other catalogs to determine their properties. The quality factor (q) is a measure of they reliability of the source as a potential calibrator. q=3 indicates good primary calibrators, q=2 indicates potentially good primary calibrators, and q=1 indicates sources that are resolved or faint or both. All WENSS peak flux densities in this paper include a correction factor of 0.9 with respect to the original catalogue to place them in the RCB scale. (1 data file).

  6. Calibration of platinum resistance thermometers.

    NASA Technical Reports Server (NTRS)

    Sinclair, D. H.; Terbeek, H. G.; Malone, J. H.

    1972-01-01

    Results of five years experience in calibrating about 1000 commercial platinum resistance thermometers (PRT) are reported. These PRT were relatively small and rugged, with ice-point resistances from 200 to 5000 ohms. Calibrations normalized in terms of resistance-difference ratios (Cragoe Z function) were found to be remarkably uniform for five of six different types of PRT tested, and to agree very closely with normalized calibrations of the primary reference standard type PRT. The Z function normalization cancels residual resistances which are not temperature dependent and simplifies interpolation between calibration points when the quality of a given type of PRT has been established in terms of uniform values of the Z function. Measurements at five or six well spaced base-point temperatures with Z interpolation will suffice to calibrate a PRT accurately from 4 to 900 K.

  7. Permanently calibrated interpolating time counter

    NASA Astrophysics Data System (ADS)

    Jachna, Z.; Szplet, R.; Kwiatkowski, P.; Ró?yc, K.

    2015-01-01

    We propose a new architecture of an integrated time interval counter that provides its permanent calibration in the background. Time interval measurement and the calibration procedure are based on the use of a two-stage interpolation method and parallel processing of measurement and calibration data. The parallel processing is achieved by a doubling of two-stage interpolators in measurement channels of the counter, and by an appropriate extension of control logic. Such modification allows the updating of transfer characteristics of interpolators without the need to break a theoretically infinite measurement session. We describe the principle of permanent calibration, its implementation and influence on the quality of the counter. The precision of the presented counter is kept at a constant level (below 20?ps) despite significant changes in the ambient temperature (from ?10 to 60?°C), which can cause a sevenfold decrease in the precision of the counter with a traditional calibration procedure.

  8. 42 CFR 493.1255 - Standard: Calibration and calibration verification procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Standard: Calibration and calibration verification procedures. 493.1255 Section... Analytic Systems § 493.1255 Standard: Calibration and calibration verification procedures....

  9. 42 CFR 493.1255 - Standard: Calibration and calibration verification procedures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Standard: Calibration and calibration verification procedures. 493.1255 Section... Analytic Systems § 493.1255 Standard: Calibration and calibration verification procedures....

  10. 42 CFR 493.1255 - Standard: Calibration and calibration verification procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Standard: Calibration and calibration verification procedures. 493.1255 Section... Analytic Systems § 493.1255 Standard: Calibration and calibration verification procedures....

  11. 42 CFR 493.1255 - Standard: Calibration and calibration verification procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Standard: Calibration and calibration verification procedures. 493.1255 Section... Analytic Systems § 493.1255 Standard: Calibration and calibration verification procedures....

  12. 42 CFR 493.1255 - Standard: Calibration and calibration verification procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Standard: Calibration and calibration verification procedures. 493.1255 Section... Analytic Systems § 493.1255 Standard: Calibration and calibration verification procedures....

  13. A comparison of methods for calibrating parallel-plate chambers/.

    PubMed

    Reft, C S; Kuchnir, F T; DeWerd, L A; Micka, J; Attix, F H

    1994-12-01

    All dosimetry protocols for calibrating the output of electron beams recommend the use of parallel-plate ionization chambers, but the method of determining their value of Ngas is a matter of concern. The AAPM Protocol (TG 21) recommends a direct comparison with a calibrated cylindrical chamber in phantom at dmax with the highest available electron energy beam. This must be done by the user. Since all calibration laboratories traditionally use 60Co for megavoltage chamber calibrations, two alternate procedures based on exposures in-air, or in-phantom, have been proposed. All methods use correction factors in the data reduction. To verify the consistency of the three methods, we have measured Ngas using each of these techniques for six of the most commonly used and commercially-available parallel-plate ionization chambers. The paired cylindrical and parallel-plate ionization chambers, and phantom materials/buildup caps were matched to the wall composition of the plane chambers, as recommended in TG 39. A 22 MeV electron beam was used for the electron irradiations. The ionization chambers were then taken to an Accredited Dosimetry Calibration Laboratory (ADCL), where 60Co calibrations were performed. The results demonstrate that, by using the appropriate correction factors for the chambers described in this work, all three methods yield values for Ngas that are within 1% of each other. PMID:7700203

  14. BXS Re-calibration

    SciTech Connect

    Welch, J; /SLAC; ,

    2010-11-24

    Early in the commissioning it was noticed by Cecile Limborg that the calibration of the BXS spectrometer magnet seemed to be different from the strength of the BX01/BX02 magnets. First the BX01/BX02 currents were adjusted to 135 MeV and the beam energy was adjusted to make the horizontal orbit flat. Then BX01/BX02 magnets were switched off and BXS was adjusted to make the horizontal orbit in the spectrometer line flat, without changing the energy of the beam. The result was that about 140-141 MeV were required on the BXS magnet. This measurement was repeated several times by others with the same results. It was not clear what was causing the error: magnet strength or layout. A position error of about 19 mm of the BXS magnet could explain the difference. Because there was a significant misalignment of the vacuum chamber in the BXS line, the alignment of the whole spectrometer line was checked. The vacuum chamber was corrected, but the magnets were found to be in the proper alignment. So we were left with one (or conceivably two) magnet calibration errors. Because BXS is a wedged shaped magnet, the bend angle depends on the horizontal position of the incoming beam. As mentioned, an offset of the beam position of 19 mm would increase or decrease the bend angle roughly by the ratio of 135/141. The figure of 19 mm is special and caused a considerable confusion during the design and measurement of the BXS magnet. This is best illustrated in Figure 1 which was taken out of the BXS Traveler document. The distance between the horizontal midplanes of the poles and the apex of the beam path was chosen to be 19 mm so the beam is close to the good field region throughout its entire path. Thus it seemed possible that there was an error that resulted in the beam not being on this trajectory, or conversely, that the magnetic measurements were done on the wrong trajectory and the magnet was then mis-calibrated. Mechanical measurements of the vacuum chamber made in the tunnel indicated that the vacuum chamber was in fact in the proper position with respect to the magnet - not 19 mm off to one side - so the former possibility was discounted. Review of the Fiducial Report and an interview with Keith Caban convinced me that there was no error in the coordinate system used for magnet measurements. I went and interviewed Andrew Fischer who did the magnetic measurements of BXS. He had extensive records, including photographs of the setups and could quickly answer quite detailed questions about how the measurement was done. Before the interview, I had a suspicion there might have been a sign flip in the x coordinate which because of the wedge would result in the wrong path length and a miscalibration. Andrew was able to pin-point how this could have happened and later confirmed it by looking an measurement data from the BXG magnet done just after BXS and comparing photographs. It turned out that the sign of the horizontal stage travel that drives the measurement wire was opposite that of the x coordinate in the Traveler, and the sign difference wasn't applied to the data. The origin x = 0 was set up correctly, but the wire moved in the opposite direction to what was expected, just as if the arc had been flipped over about the origin. To quantitatively confirm that this was the cause of the observed difference in calibration I used the 'grid data', which was taken with a Hall probe on the BXS magnet originally to measure the FINT (focusing effect) term, and combined it with the Hall probe data taken on the flipped trajectory, and performed the field integral on a path that should give the same result as the design path. This is best illustrated in Figure 2. The integration path is coincident with the desired path from the pivot points (x = 0) outward. Between the pivot points the integration path is a mirror image of the design path, but because the magnet is fairly uniform, for this portion it gives the same result. Most of the calibration error resulted simply from the different path length between the design path and the measured path. The res

  15. Calibration of the MAGIC Telescope Using Muon Ring Images

    NASA Astrophysics Data System (ADS)

    Shayduk, M.; Kalekin, O.; Mase, K.; Pavel, N.; MAGIC Collaboration

    2003-07-01

    The new 17m MAGIC telescope will operate at extremely low energy threshold for Air Cherenkov detectors. In order to restore primary spectra, it is necessary to have an absolute light calibration of the telescope camera. A system for such optical calibration is already realized in the MAGIC project. One can use muon ring images as another possibility to perform the calibration. Cherenkov light from local muons and gamma-induced showers has the similar spectrum. Parameters of muon (energy, impact parameter, inclination angle) can be obtained from the muon ring image. Using these muon parameters one can calculate the total amount of Cherenkov light in the telescope camera analytically. Thus, a conversion factor from photons to ADC count can be determined. In this report we present a method of the MAGIC telescope calibration with muon rings.

  16. Germanium resistance thermometer calibration at superfluid helium temperatures

    SciTech Connect

    Mason, F.C.

    1985-01-01

    The rapid increase in resistance of high purity semi-conducting germanium with decreasing temperature in the superfluid helium range of temperatures makes this material highly adaptable as a very sensitive thermometer. Also, a germanium thermometer exhibits a highly reproducible resistance versus temperature characteristic curve upon cycling between liquid helium temperatures and room temperature. These two factors combine to make germanium thermometers ideally suited for measuring temperatures in many cryogenic studies at superfluid helium temperatures. One disadvantage, however, is the relatively high cost of calibrated germanium thermometers. In space helium cryogenic systems, many such thermometers are often required, leading to a high cost for calibrated thermometers. The construction of a thermometer calibration cryostat and probe which will allow for calibrating six germanium thermometers at one time, thus effecting substantial savings in the purchase of thermometers is considered.

  17. Gulf of Mexico Climate-History Calibration Study

    USGS Publications Warehouse

    Spear, Jessica W.; Poore, Richard Z.

    2010-01-01

    Reliable instrumental records of past climate are available for about the last 150 years only. To supplement the instrumental record, reconstructions of past climate are made from natural recorders such as trees, ice, corals, and microfossils preserved in sediments. These proxy records provide information on the rate and magnitude of past climate variability, factors that are critical to distinguishing between natural and human-induced climate change in the present. However, the value of proxy records is heavily dependent on calibration between the chemistry of the natural recorder and of the modern environmental conditions. The Gulf of Mexico Climate and Environmental History Project is currently undertaking a climate-history calibration study with material collected from an automated sediment trap. The primary focus of the calibration study is to provide a better calibration of low-latitude environmental conditions and shell chemistry of calcareous microfossils, such as planktic Foraminifera.

  18. Calibration of CR-39-based thoron progeny device.

    PubMed

    Fábián, F; Csordás, A; Shahrokhi, A; Somlai, J; Kovács, T

    2014-07-01

    Radon isotopes and their progenies have proven significant role in respiratory tumour formation. In most cases, the radiological effect of one of the radon isotopes (thoron) and its progenies has been neglected together with its measurement technique; however, latest surveys proved that thoron's existence is expectable in flats and in workplace in Europe. Detectors based on different track detector measurement technologies have recently spread for measuring thoron progenies; however, the calibration is not yet completely elaborated. This study deals with the calibration of the track detector measurement method suitable for measuring thoron progenies using different devices with measurement techniques capable of measuring several progenies (Pylon AB5 and WLx, Sarad EQF 3220). The calibration factor values related to the thoron progeny monitors, the measurement uncertainty, reproducibility and other parameters were found using the calibration chamber. In the future, the effects of the different parameters (aerosol distribution, etc.) will be determined. PMID:24723185

  19. Mercury Continuous Emmission Monitor Calibration

    SciTech Connect

    John Schabron; Eric Kalberer; Ryan Boysen; William Schuster; Joseph Rovani

    2009-03-12

    Mercury continuous emissions monitoring systems (CEMs) are being implemented in over 800 coal-fired power plant stacks throughput the U.S. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor calibrators/generators. These devices are used to calibrate mercury CEMs at power plant sites. The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005 and vacated by a Federal appeals court in early 2008 required that calibration be performed with NIST-traceable standards. Despite the vacature, mercury emissions regulations in the future will require NIST traceable calibration standards, and EPA does not want to interrupt the effort towards developing NIST traceability protocols. The traceability procedures will be defined by EPA. An initial draft traceability protocol was issued by EPA in May 2007 for comment. In August 2007, EPA issued a conceptual interim traceability protocol for elemental mercury calibrators. The protocol is based on the actual analysis of the output of each calibration unit at several concentration levels ranging initially from about 2-40 {micro}g/m{sup 3} elemental mercury, and in the future down to 0.2 {micro}g/m{sup 3}, and this analysis will be directly traceable to analyses by NIST. The EPA traceability protocol document is divided into two separate sections. The first deals with the qualification of calibrator models by the vendors for use in mercury CEM calibration. The second describes the procedure that the vendors must use to certify the calibrators that meet the qualification specifications. The NIST traceable certification is performance based, traceable to analysis using isotope dilution inductively coupled plasma/mass spectrometry (ID/ICP/MS) performed by NIST in Gaithersburg, MD. The outputs of mercury calibrators are compared to one another using a nesting procedure which allows direct comparison of one calibrator with another at specific concentrations and eliminates analyzer variability effects. The qualification portion of the EPA interim traceability protocol requires the vendors to define calibrator performance as affected by variables such as pressure, temperature, line voltage, and shipping. In 2007 WRI developed and conducted a series of simplified qualification experiments to determine actual calibrator performance related to the variables defined in the qualification portion of the interim protocol.

  20. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Dynamometer calibration. 89.307 Section 89.307 Protection...Provisions § 89.307 Dynamometer calibration. (a) If necessary, follow the... (2) Determine the dynamometer calibration moment arm (a distance/weight...

  1. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 2013-07-01 true Dynamometer calibration. 89.307 Section 89.307 Protection...Provisions § 89.307 Dynamometer calibration. (a) If necessary, follow the... (2) Determine the dynamometer calibration moment arm (a distance/weight...

  2. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Dynamometer calibration. 89.307 Section 89.307 Protection...Provisions § 89.307 Dynamometer calibration. (a) If necessary, follow the... (2) Determine the dynamometer calibration moment arm (a distance/weight...

  3. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Dynamometer calibration. 89.307 Section 89.307 Protection...Provisions § 89.307 Dynamometer calibration. (a) If necessary, follow the... (2) Determine the dynamometer calibration moment arm (a distance/weight...

  4. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Dynamometer calibration. 89.307 Section 89.307 Protection...Provisions § 89.307 Dynamometer calibration. (a) If necessary, follow the... (2) Determine the dynamometer calibration moment arm (a distance/weight...

  5. Camera calibration based on parallel lines

    NASA Astrophysics Data System (ADS)

    Li, Weimin; Zhang, Yuhai; Zhao, Yu

    2015-01-01

    Nowadays, computer vision has been wildly used in our daily life. In order to get some reliable information, camera calibration can not be neglected. Traditional camera calibration cannot be used in reality due to the fact that we cannot find the accurate coordinate information of the referenced control points. In this article, we present a camera calibration algorithm which can determine the intrinsic parameters both with the extrinsic parameters. The algorithm is based on the parallel lines in photos which can be commonly find in the real life photos. That is we can first get the intrinsic parameters as well as the extrinsic parameters though the information picked from the photos we take from the normal life. More detail, we use two pairs of the parallel lines to compute the vanishing points, specially if these parallel lines are perpendicular, which means these two vanishing points are conjugate with each other, we can use some views (at least 5 views) to determine the image of the absolute conic(IAC). Then, we can easily get the intrinsic parameters by doing cholesky factorization on the matrix of IAC.As we all know, when connect the vanishing point with the camera optical center, we can get a line which is parallel with the original lines in the scene plane. According to this, we can get the extrinsic parameters R and T. Both the simulation and the experiment results meets our expectations.

  6. Integrated calibration of magnetic gradient tensor system

    NASA Astrophysics Data System (ADS)

    Gang, Yin; Yingtang, Zhang; Hongbo, Fan; GuoQuan, Ren; Zhining, Li

    2015-01-01

    Measurement precision of a magnetic gradient tensor system is not only connected with the imperfect performance of magnetometers such as bias, scale factor, non-orthogonality and misalignment errors, but also connected with the external soft-iron and hard-iron magnetic distortion fields when the system is used as a strapdown device. So an integrated scalar calibration method is proposed in this paper. In the first step, a mathematical model for scalar calibration of a single three-axis magnetometer is established, and a least squares ellipsoid fitting algorithm is proposed to estimate the detailed error parameters. For the misalignment errors existing at different magnetometers caused by the installation process and misalignment errors aroused by ellipsoid fitting estimation, a calibration method for combined misalignment errors is proposed in the second step to switch outputs of different magnetometers into the ideal reference orthogonal coordinate system. In order to verify effectiveness of the proposed method, simulation and experiment with a cross-magnetic gradient tensor system are performed, and the results show that the proposed method estimates error parameters and improves the measurement accuracy of magnetic gradient tensor greatly.

  7. A Novel Protocol for Model Calibration in Biological Wastewater Treatment

    PubMed Central

    Zhu, Ao; Guo, Jianhua; Ni, Bing-Jie; Wang, Shuying; Yang, Qing; Peng, Yongzhen

    2015-01-01

    Activated sludge models (ASMs) have been widely used for process design, operation and optimization in wastewater treatment plants. However, it is still a challenge to achieve an efficient calibration for reliable application by using the conventional approaches. Hereby, we propose a novel calibration protocol, i.e. Numerical Optimal Approaching Procedure (NOAP), for the systematic calibration of ASMs. The NOAP consists of three key steps in an iterative scheme flow: i) global factors sensitivity analysis for factors fixing; ii) pseudo-global parameter correlation analysis for non-identifiable factors detection; and iii) formation of a parameter subset through an estimation by using genetic algorithm. The validity and applicability are confirmed using experimental data obtained from two independent wastewater treatment systems, including a sequencing batch reactor and a continuous stirred-tank reactor. The results indicate that the NOAP can effectively determine the optimal parameter subset and successfully perform model calibration and validation for these two different systems. The proposed NOAP is expected to use for automatic calibration of ASMs and be applied potentially to other ordinary differential equations models. PMID:25682959

  8. A Novel Protocol for Model Calibration in Biological Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Zhu, Ao; Guo, Jianhua; Ni, Bing-Jie; Wang, Shuying; Yang, Qing; Peng, Yongzhen

    2015-02-01

    Activated sludge models (ASMs) have been widely used for process design, operation and optimization in wastewater treatment plants. However, it is still a challenge to achieve an efficient calibration for reliable application by using the conventional approaches. Hereby, we propose a novel calibration protocol, i.e. Numerical Optimal Approaching Procedure (NOAP), for the systematic calibration of ASMs. The NOAP consists of three key steps in an iterative scheme flow: i) global factors sensitivity analysis for factors fixing; ii) pseudo-global parameter correlation analysis for non-identifiable factors detection; and iii) formation of a parameter subset through an estimation by using genetic algorithm. The validity and applicability are confirmed using experimental data obtained from two independent wastewater treatment systems, including a sequencing batch reactor and a continuous stirred-tank reactor. The results indicate that the NOAP can effectively determine the optimal parameter subset and successfully perform model calibration and validation for these two different systems. The proposed NOAP is expected to use for automatic calibration of ASMs and be applied potentially to other ordinary differential equations models.

  9. A novel protocol for model calibration in biological wastewater treatment.

    PubMed

    Zhu, Ao; Guo, Jianhua; Ni, Bing-Jie; Wang, Shuying; Yang, Qing; Peng, Yongzhen

    2015-01-01

    Activated sludge models (ASMs) have been widely used for process design, operation and optimization in wastewater treatment plants. However, it is still a challenge to achieve an efficient calibration for reliable application by using the conventional approaches. Hereby, we propose a novel calibration protocol, i.e. Numerical Optimal Approaching Procedure (NOAP), for the systematic calibration of ASMs. The NOAP consists of three key steps in an iterative scheme flow: i) global factors sensitivity analysis for factors fixing; ii) pseudo-global parameter correlation analysis for non-identifiable factors detection; and iii) formation of a parameter subset through an estimation by using genetic algorithm. The validity and applicability are confirmed using experimental data obtained from two independent wastewater treatment systems, including a sequencing batch reactor and a continuous stirred-tank reactor. The results indicate that the NOAP can effectively determine the optimal parameter subset and successfully perform model calibration and validation for these two different systems. The proposed NOAP is expected to use for automatic calibration of ASMs and be applied potentially to other ordinary differential equations models. PMID:25682959

  10. 21 CFR 862.1150 - Calibrator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1150 Calibrator. (a) Identification. A calibrator...

  11. 21 CFR 862.1150 - Calibrator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1150 Calibrator. (a) Identification. A calibrator...

  12. Rotary mode system initial instrument calibration

    SciTech Connect

    Johns, B.R.

    1994-10-01

    The attached report contains the vendor calibration procedures used for the initial instrument calibration of the rotary core sampling equipment. The procedures are from approved vendor information files.

  13. Multi-syringe chromatography (MSC) system for the on-line solid-phase extraction and determination of hydrochlorothiazide and losartan potassium in superficial water, groundwater and wastewater outlet samples

    Microsoft Academic Search

    María Antonieta Obando; José Manuel Estela; Víctor Cerdà

    2008-01-01

    In this paper, a combination of multi-syringe chromatography analysis technique with extraction disks sorbents for the pre-concentration and determination of hydrochlorothiazide and losartan potassium in superficial water, groundwater and wastewater outlet samples has been developed. The system developed was proved for the determination of hydrochlorothiazide and losartan potassium in spiked water samples with recoveries ranging from 95 to 118%. The

  14. Immunogenicity and safety of measles-mumps-rubella vaccine delivered by disposable-syringe jet injector in healthy Brazilian infants: A randomized non-inferiority study.

    PubMed

    de Menezes Martins, Reinaldo; Curran, Birute; Maia, Maria de Lourdes Sousa; Ribeiro, Maria das Graças Tavares; Camacho, Luiz Antonio Bastos; da Silva Freire, Marcos; Yamamura, Anna Maya Yoshida; Siqueira, Marilda Mendonça; Lemos, Maria Cristina F; de Albuquerque, Elizabeth Maciel; von Doellinger, Vanessa Dos Reis; Homma, Akira; Saganic, Laura; Jarrahian, Courtney; Royals, Michael; Zehrung, Darin

    2015-03-01

    This study aimed to determine if immunogenicity to measles-mumps-rubella vaccine delivered to infants via a disposable-syringe jet injector (DSJI) was non-inferior to that administered by needle and syringe (NS). Vaccination safety was evaluated, as were the use, performance, and acceptability of each delivery method. The DSJI was the PharmaJet® 2009 generation-1 device (G1) and the vaccine was measles-mumps-rubella vaccine from Bio-Manguinhos. Five hundred eighty-two healthy Brazilian infants were randomized to receive vaccine via G1 or NS. Seroconversion rates against measles and mumps viruses in the G1 treatment group did not meet non-inferiority criteria when compared with the NS group; however, responses in the G1 group to rubella virus were non-inferior to those of NS vaccinees. Most adverse events were mild or moderate. Crying after injection was more frequent in the NS group, and local skin reactions were more common in the G1 group. Five serious adverse events were judged causally unrelated to treatment and all resolved. Parents/guardians expressed a strong preference for G1 over NS for their children. Vaccinators found the G1 easy to use but noted incomplete vaccine delivery in some cases. Although the G1 has been superseded by an updated device, our results are important for the continued improvement and evaluation of DSJIs, which have the potential to overcome many of the challenges and risks associated with needle-based injections worldwide. Recommendations for future DSJI clinical studies include rigorous training of vaccinators, quantitative measurement of wetness on the skin following injection, and regular monitoring of device and vaccinator performance. PMID:25476584

  15. Calibrating Pesticide Application Ground Equipment

    E-print Network

    Shaw, Bryan W.

    2000-07-05

    This pocket-sized guide gives step-by-step instructions for calibrating ground sprayers. Tables provide instructions, examples and sample formulas for determining speed of application, flow rate and the amount of pesticide to add to the tank....

  16. Constructing and Calibrating a Hydrometer

    NSDL National Science Digital Library

    Meghan Hauptli

    2012-04-18

    Students construct and calibrate a simple hydrometer using different salt solutions. They then graph their data and determine the density and salinity of an unknown solution using their hydrometer and graphical analysis.

  17. The calibration methods for Multi-Filter Rotating Shadowband Radiometer: a review

    NASA Astrophysics Data System (ADS)

    Chen, Maosi; Davis, John; Tang, Hongzhao; Ownby, Carolyn; Gao, Wei

    2013-09-01

    The continuous, over two-decade data record from the Multi-Filter Rotating Shadowband Radiometer (MFRSR) is ideal for climate research which requires timely and accurate information of important atmospheric components such as gases, aerosols, and clouds. Except for parameters derived from MFRSR measurement ratios, which are not impacted by calibration error, most applications require accurate calibration factor(s), angular correction, and spectral response function(s) from calibration. Although a laboratory lamp (or reference) calibration can provide all the information needed to convert the instrument readings to actual radiation, in situ calibration methods are implemented routinely (daily) to fill the gaps between lamp calibrations. In this paper, the basic structure and the data collection and pretreatment of the MFRSR are described. The laboratory lamp calibration and its limitations are summarized. The cloud screening algorithms for MFRSR data are presented. The in situ calibration methods, the standard Langley method and its variants, the ratio-Langley method, the general method, Alexandrov's comprehensive method, and Chen's multi-channel method, are outlined. The reason that all these methods do not fit for all situations is that they assume some properties, such as aerosol optical depth (AOD), total optical depth (TOD), precipitable water vapor (PWV), effective size of aerosol particles, or angstrom coefficient, are invariant over time. These properties are not universal and some of them rarely happen. In practice, daily calibration factors derived from these methods should be smoothed to restrain error.

  18. Multidetector calibration for mass spectrometers

    Microsoft Academic Search

    C. Bayne; D. Donohue; R. Fiedler

    1994-01-01

    The International Atomic Energy Agency's Safeguards Analytical Laboratory has performed calibration experiments to measure the different efficiencies among multi-Faraday detectors for a Finnigan-MAT 261 mass spectrometer. Two types of calibration experiments were performed: (i) peak-shift experiments and (ii) peak-jump experiments. For peak-shift experiments, the ion intensities were measured for all isotopes of an element in different Faraday detectors. Repeated measurements

  19. Multidetector calibration for mass spectrometers

    Microsoft Academic Search

    C. K. Bayne; D. L. Donohue; R. Fiedler

    1994-01-01

    The International Atomic Energy Agency`s Safeguards Analytical Laboratory has performed calibration experiments to measure the different efficiencies among multi-Faraday detectors for a Finnigan-MAT 261 mass spectrometer. Two types of calibration experiments were performed: (1) peak-shift experiments and (2) peak-jump experiments. For peak-shift experiments, the ion intensities were measured for all isotopes of an element in different Faraday detectors. Repeated measurements

  20. Practical Study of Psychrometer Calibrations

    NASA Astrophysics Data System (ADS)

    Kentved, Anders Bonde; Heinonen, Martti; Hudoklin, Domen

    2012-09-01

    Psychrometers remain the most widely used instruments for controlling the humidity in climatic test chambers, yet the calibration of these instruments is particularly challenging. Psychrometer calibrations require careful consideration of influence variables such as the fitting and cleanliness of the wick, the effect of the calibration chamber on the air flow past the sensors, on radiation incident on the sensors, and on the dissipation heat from the built-in fan (if included). In addition, uncertainty requirements for calibration of such psychrometers are typically around 1 %rh to 2 %rh, i.e., close to the best calibration and measurement uncertainties (CMCs) claimed by national metrology institutes (NMIs). As well as their role in supporting CMCs, inter-comparisons provide a good test-ground to ensure all influence variables are controlled or otherwise accounted for in the uncertainty budget. This paper presents the results of a comparison of psychrometer calibrations performed by the NMIs in Denmark, Slovenia, and Finland. The comparison was carried out under EURAMET Project No. 1033 with the aim to investigate the equivalence of psychrometer calibrations performed at the highest level and to gather practical experience to be used in similar comparisons in the future. An aspirated electro-psychrometer was used for the comparison, and calibrations were carried out in the range from 15 %rh to 93 %rh in a temperature range from 15 °C to 70 °C. While the results show good agreement at high relative humidity, significant differences at low relative humidity are reported. It is suggested that the differences are caused by a combination of psychrometer wick contamination and a difference in the wick-wetting methods used by the participant laboratories.

  1. Recent Developments in Multivariate Calibration

    Microsoft Academic Search

    Jon Gabrielsson; Johan Trygg

    2006-01-01

    This review covers the area of multivariate calibration; from pre-processing of data prior to modeling and applications of regression methods for calibration and prediction. The importance of pre-treatment of data is highlighted with many of the recently developed methods together with traditional methods. Several articles provide comparisons between different pre-processing methods. Methods for data from coupled chromatographic methods, which have

  2. WFC3: UVIS Dark Calibration

    NASA Astrophysics Data System (ADS)

    Bourque, Matthew; Biretta, John A.; Anderson, Jay; Baggett, Sylvia M.; Gunning, Heather C.; MacKenty, John W.

    2014-06-01

    Wide Field Camera 3 (WFC3), a fourth-generation imaging instrument on board the Hubble Space Telescope (HST), has exhibited excellent performance since its installation during Servicing Mission 4 in May 2009. The UVIS detector, comprised of two e2v CCDs, is one of two channels available on WFC3 and is named for its ultraviolet and visible light sensitivity. We present the various procedures and results of the WFC3/UVIS dark calibration, which monitors the health and stability of the UVIS detector, provides characterization of hot pixels and dark current, and produces calibration files to be used as a correction for dark current in science images. We describe the long-term growth of hot pixels and the impacts that UVIS Charge Transfer Efficiency (CTE) losses, postflashing, and proximity to the readout amplifiers have on the population. We also discuss the evolution of the median dark current, which has been slowly increasing since the start of the mission and is currently ~6 e-/hr/pix, averaged across each chip. We outline the current algorithm for creating UVIS dark calibration files, which includes aggressive cosmic ray masking, image combination, and hot pixel flagging. Calibration products are available to the user community, typically 3-5 days after initial processing, through the Calibration Database System (CDBS). Finally, we discuss various improvements to the calibration and monitoring procedures. UVIS dark monitoring will continue throughout and beyond HST’s current proposal cycle.

  3. Comparison of Air Temperature Calibrations

    NASA Astrophysics Data System (ADS)

    Heinonen, M.; Anagnostou, M.; Bartolo, J.; Bell, S.; Benyon, R.; Bergerud, R. A.; Bojkovski, J.; Böse, N.; Dinu, C.; Smorgon, D.; Flakiewicz, K.; Martin, M. J.; Nedialkov, S.; Nielsen, M. B.; O?uz Aytekin, S.; Otych, J.; Pedersen, M.; Rujan, M.; Testa, N.; Turzó-András, E.; Vilbaste, M.; White, M.

    2014-07-01

    European national metrology institutes use calibration systems of various types for calibrating thermometers in air. These were compared to each other for the first time in a project organized by the European Association of National Metrology Institutes (EURAMET). This EURAMET P1061 comparison project had two main objectives: (1) to study the equivalence of calibrations performed by different laboratories and (2) to investigate correlations between calibration methods and achievable uncertainties. The comparison was realized using a pair of 100 platinum resistance thermometer probes connected to a digital thermometer bridge as the transfer standard. The probes had different dimensions and surface properties. The measurements covered the temperature range between and , but each laboratory chose a subrange most relevant to its scope and performed measurements at five nominal temperature points covering the subrange. To enable comparison between the laboratories, comparison reference functions were determined using weighted least-squares fitting. Various effects related to variations in heat transfer conditions were demonstrated but clear correlations to specific characteristics of calibration system were not identified. Calibrations in air and liquid agreed typically within at and . Expanded uncertainties determined by the participants ranged from to and they were shown to be realistic in most cases.

  4. Blackbody comparator for thermocouple calibration

    SciTech Connect

    Ojanen, M.; Hahtela, O. M.; Heinonen, M. [Centre for Metrology and Accreditation (MIKES), P.O.Box 9, FI-02151 Espoo (Finland)

    2013-09-11

    MIKES is developing a measurement set-up for calibrating thermocouples in the temperature range 960 °C - 1500 °C. The calibration method is based on direct comparison of thermocouples and radiation thermometers. We have designed a graphite blackbody comparator cell, which is operated in a horizontal single-zone tube furnace. The cell includes two blackbody cavities for radiation temperature measurements. The cavities have openings on opposite sides of the cell, allowing simultaneous measurement with two radiation thermometers. The design of the comparator allows three thermocouples to be calibrated simultaneously. The thermocouples to be calibrated are inserted in thermometer wells around one of the measurement cavities. We characterize the blackbody comparator in terms of repeatability, temperature distribution and emissivity. Finally, we validate the uncertainty analysis by comparing calibration results obtained for type B and S thermocouples to the calibration results reported by Technical Research Institute of Sweden (SP), and MIKES. The agreement in the temperature range 1000 °C - 1500 °C is within 0.90 °C, the average deviation being 0.17 °C.

  5. Blackbody comparator for thermocouple calibration

    NASA Astrophysics Data System (ADS)

    Ojanen, M.; Hahtela, O. M.; Heinonen, M.

    2013-09-01

    MIKES is developing a measurement set-up for calibrating thermocouples in the temperature range 960 °C - 1500 °C. The calibration method is based on direct comparison of thermocouples and radiation thermometers. We have designed a graphite blackbody comparator cell, which is operated in a horizontal single-zone tube furnace. The cell includes two blackbody cavities for radiation temperature measurements. The cavities have openings on opposite sides of the cell, allowing simultaneous measurement with two radiation thermometers. The design of the comparator allows three thermocouples to be calibrated simultaneously. The thermocouples to be calibrated are inserted in thermometer wells around one of the measurement cavities. We characterize the blackbody comparator in terms of repeatability, temperature distribution and emissivity. Finally, we validate the uncertainty analysis by comparing calibration results obtained for type B and S thermocouples to the calibration results reported by Technical Research Institute of Sweden (SP), and MIKES. The agreement in the temperature range 1000 °C - 1500 °C is within 0.90 °C, the average deviation being 0.17 °C.

  6. A First Order Wavefront Estimation Algorithm for P1640 Calibrator

    NASA Technical Reports Server (NTRS)

    Zhaia, C.; Vasisht, G.; Shao, M.; Lockhart, T.; Cady, E.; Oppenheimer, B.; Burruss, R.; Roberts, J.; Beichman, C.; Brenner, D.; Crepp, J.; Dekany, R.; Hinkley, S.; Hillenbrand, L.; Parry, I.; Pueyo, L.; Rice, E.; Roberts, L. C. Jr.; Sivaramakrishnan, A.; Soummer, R.; Vescelus, F.; Wallace, K.; Zimmerman, N.

    2012-01-01

    P1640 calibrator is a wavefront sensor working with the P1640 coronagraph and the Palomar 3000 actuator adaptive optics system (P3K) at the Palomar 200 inch Hale telescope. It measures the wavefront by interfering post-coronagraph light with a reference beam formed by low-pass filtering the blocked light from the coronagraph focal plane mask. The P1640 instrument has a similar architecture to the Gemini Planet Imager (GPI) and its performance is currently limited by the quasi-static speckles due to non-common path wavefront errors, which comes from the non-common path for the light to arrive at the AO wavefront sensor and the coronagraph mask. By measuring the wavefront after the coronagraph mask, the non-common path wavefront error can be estimated and corrected by feeding back the error signal to the deformable mirror (DM) of the P3K AO system. Here, we present a first order wavefront estimation algorithm and an instrument calibration scheme used in experiments done recently at Palomar observatory. We calibrate the P1640 calibrator by measuring its responses to poking DM actuators with a sparse checkerboard pattern at different amplitudes. The calibration yields a complex normalization factor for wavefront estimation and establishes the registration of the DM actuators at the pupil camera of the P1640 calibrator, necessary for wavefront correction. Improvement of imaging quality after feeding back the wavefront correction to the AO system demonstrated the efficacy of the algorithm.

  7. A first order wavefront estimation algorithm for P1640 calibrator

    NASA Astrophysics Data System (ADS)

    Zhai, C.; Vasisht, G.; Shao, M.; Lockhart, T.; Cady, E.; Oppenheimer, B.; Burruss, R.; Roberts, J.; Beichman, C.; Brenner, D.; Crepp, J.; Dekany, R.; Hinkley, S.; Hillenbrand, L.; Ligon, E. R.; Parry, I.; Pueyo, L.; Rice, E.; Roberts, L. C.; Sivaramakrishnan, A.; Soummer, R.; Vescelus, F.; Wallace, K.; Zimmerman, N.

    2012-07-01

    P1640 calibrator is a wavefront sensor working with the P1640 coronagraph and the Palomar 3000 actuator adaptive optics system (P3K) at the Palomar 200 inch Hale telescope. It measures the wavefront by interfering post-coronagraph light with a reference beam formed by low-pass filtering the blocked light from the coronagraph focal plane mask. The P1640 instrument has a similar architecture to the Gemini Planet Imager (GPI) and its performance is currently limited by the quasi-static speckles due to non-common path wavefront errors, which comes from the non-common path for the light to arrive at the AO wavefront sensor and the coronagraph mask. By measuring the wavefront after the coronagraph mask, the non-common path wavefront error can be estimated and corrected by feeding back the error signal to the deformable mirror (DM) of the P3K AO system. Here, we present a first order wavefront estimation algorithm and an instrument calibration scheme used in experiments done recently at Palomar observatory. We calibrate the P1640 calibrator by measuring its responses to poking DM actuators with a sparse checkerboard pattern at different amplitudes. The calibration yields a complex normalization factor for wavefront estimation and establishes the registration of the DM actuators at the pupil camera of the P1640 calibrator, necessary for wavefront correction. Improvement of imaging quality after feeding back the wavefront correction to the AO system demonstrated the efficacy of the algorithm.

  8. Low-hanging fruit for human factors design in infection prevention--still too high to reach?

    PubMed

    Clack, Lauren; Kuster, Stefan P; Giger, Heidi; Giuliani, Francesca; Sax, Hugo

    2014-06-01

    Human factors design interventions have been suggested to mitigate infection risk in health care. Among such solutions, many are easily identified and theoretically simple and quick to realize. These are called low-hanging fruit. We present a case of infection risk associated with syringe manipulation that could easily be solved by introducing user-centered design solutions. Yet, organizational complexity makes implementation of such solutions hardly reachable. We therefore advocate embedding human factors macroergonomic expertise on an organizational level. PMID:24837120

  9. Hydrologic calibration of paired watersheds using a MOSUM approach

    NASA Astrophysics Data System (ADS)

    Ssegane, H.; Amatya, D. M.; Muwamba, A.; Chescheir, G. M.; Appelboom, T.; Tollner, E. W.; Nettles, J. E.; Youssef, M. A.; Birgand, F.; Skaggs, R. W.

    2015-01-01

    Paired watershed studies have historically been used to quantify hydrologic effects of land use and management practices by concurrently monitoring two neighboring watersheds (a control and a treatment) during the calibration (pre-treatment) and post-treatment periods. This study characterizes seasonal water table and flow response to rainfall during the calibration period and tests a change detection technique of moving sums of recursive residuals (MOSUM) to select calibration periods for each control-treatment watershed pair when the regression coefficients for daily water table elevation (WTE) were most stable to reduce regression model uncertainty. The control and treatment watersheds included 1-3 year intensively managed loblolly pine (Pinus taeda L.) with natural understory, same age loblolly pine intercropped with switchgrass (Panicum virgatum), 14-15 year thinned loblolly pine with natural understory (control), and switchgrass only. Although monitoring during the calibration period spanned 2009 to 2012, silvicultural operational practices that occurred during this period such as harvesting of existing stand and site preparation for pine and switchgrass establishment may have acted as external factors, potentially shifting hydrologic calibration relationships between control and treatment watersheds. Results indicated that MOSUM was able to detect significant changes in regression parameters for WTE due to silvicultural operations. This approach also minimized uncertainty of calibration relationships which could otherwise mask marginal treatment effects. All calibration relationships developed using this MOSUM method were quantifiable, strong, and consistent with Nash-Sutcliffe Efficiency (NSE) greater than 0.97 for WTE and NSE greater than 0.92 for daily flow, indicating its applicability for choosing calibration periods of paired watershed studies.

  10. Spectral and radiometric calibration of the Airborne Visible/Infrared Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

    Vane, Gregg; Chrien, Thomas G.; Miller, Edward A.; Reimer, John H.

    1987-01-01

    The laboratory spectral and radiometric calibration of the AVIRIS science data collected since 1987 is described. The instrumentation and procedures used in the calibration are discussed and the accuracy achieved in the laboratory as determined by measurement and calculation is compared with the requirements. Instrument performance factors affecting radiometry are described. The paper concludes with a discussion of future plans.

  11. Contributions of Metacognitive and Self-Regulated Learning Theories to Investigations of Calibration of Comprehension

    ERIC Educational Resources Information Center

    Stolp, Stephanie; Zabrucky, Karen M.

    2009-01-01

    In this paper we examine the contributions of metacognitive and self-regulated learning theories to research on students' calibration of comprehension. Historically, cognitive psychologists have studied calibration of comprehension within a purely metacognitive framework, with an emphasis on the role of text and task factors but little…

  12. 40 CFR 86.522-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...use of a single calibration factor for that range. If the deviation exceeds 2 percent at any point, the best-fit non-linear equation which represents the data to within 2 percent of each test point shall be used to determine...

  13. 40 CFR 86.522-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...use of a single calibration factor for that range. If the deviation exceeds 2 percent at any point, the best-fit non-linear equation which represents the data to within 2 percent of each test point shall be used to determine...

  14. 40 CFR 86.522-78 - Carbon monoxide analyzer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...use of a single calibration factor for that range. If the deviation exceeds 2 percent at any point, the best-fit non-linear equation which represents the data to within 2 percent of each test point shall be used to determine...

  15. Calibration and verification of risk algorithms using logistic regression

    Microsoft Academic Search

    Jonathan Yuen; Eva Twengström; Roland Sigvald

    1996-01-01

    The use of logistic regression is proposed as a method of verifying and calibrating disease risk algorithms. The logistic regression model calculates the log of the odds of a binary outcome as a function of a linear combination of predictors. The resulting model assumes a multiplicative (relative) relationship between the different risk factors. Computer programs for performing logistic regression produce

  16. Evaluation of Procedures for Linking Multidimensional Item Calibrations.

    ERIC Educational Resources Information Center

    Oshima, T. C.; Davey, T. C.

    This paper evaluated multidimensional linking procedures with which multidimensional test data from two separate calibrations were put on a common scale. Data were simulated with known ability distributions varying on two factors which made linking necessary: mean vector differences and variance-covariance (v-c) matrix differences. After the…

  17. A positioning free calibration method for mobile laser scanning applications

    NASA Astrophysics Data System (ADS)

    Le Scouarnec, R.; Touzé, T.; Lacambre, J. B.; Seube, N.

    2013-10-01

    Mobile laser scanning are likely to find more and more applications for high density 3D environmental data. A mobile laser scanning system is composed by three subsystems: a GNSS (Global Navigation Satellite System) that provides position information, an INS (Inertial Navigation System) for attitude determination, and a LiDAR (Light Detection And Ranging). The accuracy of the geolocated LiDAR returns depends on the accuracy of each instrument but also on the bore-sighting parameters and the lever arms between the instruments. Indeed, an imperfect calibration may lead to systematic errors. Calibration may then become the limiting factor of Terrestrial Laser scanning if it is not tackled seriously. Moreover [Ø], it is important to have a reliable value of the calibration precision. This paper presents a new positioning free procedure for the estimation of the LiDAR bore-sighting parameters. Since this method is static, lever arms do not affect the boresight calibration and positioning is not required. That makes the methodology immune to GPS errors. Finally, since it is based on a rigorous mathematical model, it can provide a reliable boresight quality factor. First, the boresight determination problem is explained and existing calibration procedures are introduced. After having explained their drawbacks, a new procedure that tries to overcome these limitations is described. Tests from simulations and real datasets are also presented to illustrate our approach.

  18. SCUBA-2: on-sky calibration using submillimetre standard sources

    NASA Astrophysics Data System (ADS)

    Dempsey, J. T.; Friberg, P.; Jenness, T.; Tilanus, R. P. J.; Thomas, H. S.; Holland, W. S.; Bintley, D.; Berry, D. S.; Chapin, E. L.; Chrysostomou, A.; Davis, G. R.; Gibb, A. G.; Parsons, H.; Robson, E. I.

    2013-04-01

    SCUBA-2 is a 10 000-bolometer submillimetre camera on the James Clerk Maxwell Telescope. The instrument commissioning was completed in 2011 September, and full science operations began in 2011 October. To harness the full potential of this powerful new astronomical tool, the instrument calibration must be accurate and well understood. To this end, the algorithms for calculating the line-of-sight opacity have been improved, and the derived atmospheric extinction relationships at both wavebands of the SCUBA-2 instrument are presented. The results from over 500 primary and secondary calibrator observations have allowed accurate determination of the flux conversion factors (FCF) for the 850 and 450 ?m arrays. Descriptions of the instrument beam shape and photometry methods are presented. The calibration factors are well determined, with relative calibration accuracy better than 5 per cent at 850 ?m and 10 per cent at 450 ?m, reflecting the success of the derived opacity relations as well as the stability of the performance of the instrument over several months. The sample size of the calibration observations and accurate FCFs have allowed the determination of the 850 and 450 ?m fluxes of several well-known submillimetre sources, and these results are compared with previous measurements from SCUBA.

  19. Design, manufacture, and calibration of infrared radiometric blackbody sources

    SciTech Connect

    Byrd, D.A.; Michaud, F.D.; Bender, S.C. [and others

    1996-04-01

    A Radiometric Calibration Station (RCS) is being assembled at the Los Alamos National Laboratories (LANL) which will allow for calibration of sensors with detector arrays having spectral capability from about 0.4-15 {mu}m. The configuration of the LANL RCS. Two blackbody sources have been designed to cover the spectral range from about 3-15 {mu}m, operating at temperatures ranging from about 180-350 K within a vacuum environment. The sources are designed to present a uniform spectral radiance over a large area to the sensor unit under test. The thermal uniformity requirement of the blackbody cavities has been one of the key factors of the design, requiring less than 50 mK variation over the entire blackbody surface to attain effective emissivity values of about 0.999. Once the two units are built and verified to the level of about 100 mK at LANL, they will be sent to the National Institute of Standards and Technology (NIST), where at least a factor of two improvement will be calibrated into the blackbody control system. The physical size of these assemblies will require modifications of the existing NIST Low Background Infrared (LBIR) Facility. LANL has constructed a bolt-on addition to the LBIR facility that will allow calibration of our large aperture sources. Methodology for attaining the two blackbody sources at calibrated levels of performance equivalent to present state of the art will be explained in the following.

  20. Calibration issues for neutron diagnostics

    SciTech Connect

    Sadler, G.J. [JET Joint Undertaking, Abingdon (United Kingdom); Adams, J.M. [AEA Technology, Harwell (United Kingdom); Barnes, C.W. [Los Alamos National Lab., NM (United States)] [and others

    1997-12-01

    The performance of diagnostic systems are limited by their weakest constituents, including their calibration issues. Neutron diagnostics are notorious for problems encountered while determining their absolute calibrations, due mainly to the nature of the neutron transport problem. In order to facilitate the determination of an accurate and precise calibration, the diagnostic design should be such as to minimize the scattered neutron flux. ITER will use a comprehensive set of neutron diagnostics--comprising radial and vertical neutron cameras, neutron spectrometers, a neutron activation system and internal and external fission chambers--to provide accurate measurements of fusion power and power densities as a function of time. The calibration of such an important diagnostic system merits careful consideration. Some thoughts have already been given to this subject during the conceptual design phase in relation to the time-integrated neutron activation and time-dependent neutron yield monitors. However, no overall calibration strategy has been worked out so far. This paper represents a first attempt to address this vital issue. Experience gained from present large tokamaks (JET, TFTR and JT60U) and proposals for ITER are reviewed. The need to use a 14-MeV neutron generator as opposed to radioactive sources for in-situ calibration of D-T diagnostics will be stressed. It is clear that the overall absolute determination of fusion power will have to rely on a combination of nuclear measuring techniques, for which the provision of accurate and independent calibrations will constitute an ongoing process as ITER moves from one phase of operation to the next.

  1. Single-Vector Calibration of Wind-Tunnel Force Balances

    NASA Technical Reports Server (NTRS)

    Parker, P. A.; DeLoach, R.

    2003-01-01

    An improved method of calibrating a wind-tunnel force balance involves the use of a unique load application system integrated with formal experimental design methodology. The Single-Vector Force Balance Calibration System (SVS) overcomes the productivity and accuracy limitations of prior calibration methods. A force balance is a complex structural spring element instrumented with strain gauges for measuring three orthogonal components of aerodynamic force (normal, axial, and side force) and three orthogonal components of aerodynamic torque (rolling, pitching, and yawing moments). Force balances remain as the state-of-the-art instrument that provide these measurements on a scale model of an aircraft during wind tunnel testing. Ideally, each electrical channel of the balance would respond only to its respective component of load, and it would have no response to other components of load. This is not entirely possible even though balance designs are optimized to minimize these undesirable interaction effects. Ultimately, a calibration experiment is performed to obtain the necessary data to generate a mathematical model and determine the force measurement accuracy. In order to set the independent variables of applied load for the calibration 24 NASA Tech Briefs, October 2003 experiment, a high-precision mechanical system is required. Manual deadweight systems have been in use at Langley Research Center (LaRC) since the 1940s. These simple methodologies produce high confidence results, but the process is mechanically complex and labor-intensive, requiring three to four weeks to complete. Over the past decade, automated balance calibration systems have been developed. In general, these systems were designed to automate the tedious manual calibration process resulting in an even more complex system which deteriorates load application quality. The current calibration approach relies on a one-factor-at-a-time (OFAT) methodology, where each independent variable is incremented individually throughout its full-scale range, while all other variables are held at a constant magnitude. This OFAT approach has been widely accepted because of its inherent simplicity and intuitive appeal to the balance engineer. LaRC has been conducting research in a "modern design of experiments" (MDOE) approach to force balance calibration. Formal experimental design techniques provide an integrated view to the entire calibration process covering all three major aspects of an experiment; the design of the experiment, the execution of the experiment, and the statistical analyses of the data. In order to overcome the weaknesses in the available mechanical systems and to apply formal experimental techniques, a new mechanical system was required. The SVS enables the complete calibration of a six-component force balance with a series of single force vectors.

  2. Waveguide Calibrator for Multi-Element Probe Calibration

    NASA Technical Reports Server (NTRS)

    Sommerfeldt, Scott D.; Blotter, Jonathan D.

    2007-01-01

    A calibrator, referred to as the spider design, can be used to calibrate probes incorporating multiple acoustic sensing elements. The application is an acoustic energy density probe, although the calibrator can be used for other types of acoustic probes. The calibrator relies on the use of acoustic waveguide technology to produce the same acoustic field at each of the sensing elements. As a result, the sensing elements can be separated from each other, but still calibrated through use of the acoustic waveguides. Standard calibration techniques involve placement of an individual microphone into a small cavity with a known, uniform pressure to perform the calibration. If a cavity is manufactured with sufficient size to insert the energy density probe, it has been found that a uniform pressure field can only be created at very low frequencies, due to the size of the probe. The size of the energy density probe prevents one from having the same pressure at each microphone in a cavity, due to the wave effects. The "spider" design probe is effective in calibrating multiple microphones separated from each other. The spider design ensures that the same wave effects exist for each microphone, each with an indivdual sound path. The calibrator s speaker is mounted at one end of a 14-cm-long and 4.1-cm diameter small plane-wave tube. This length was chosen so that the first evanescent cross mode of the plane-wave tube would be attenuated by about 90 dB, thus leaving just the plane wave at the termination plane of the tube. The tube terminates with a small, acrylic plate with five holes placed symmetrically about the axis of the speaker. Four ports are included for the four microphones on the probe. The fifth port is included for the pre-calibrated reference microphone. The ports in the acrylic plate are in turn connected to the probe sensing elements via flexible PVC tubes. These five tubes are the same length, so the acoustic wave effects are the same in each tube. The flexible nature of the tubes allows them to be positioned so that each tube terminates at one of the microphones of the energy density probe, which is mounted in the acrylic structure, or the calibrated reference microphone. Tests performed verify that the pressure did not vary due to bends in the tubes. The results of these tests indicate that the average sound pressure level in the tubes varied by only 0.03 dB as the tubes were bent to various angles. The current calibrator design is effective up to a frequency of approximately 4.5 kHz. This upper design frequency is largely due to the diameter of the plane-wave tubes.

  3. Fisheye lens calibration using virtual grid.

    PubMed

    Arfaoui, Aymen; Thibault, Simon

    2013-04-20

    We present herein a technique to calibrate fisheye lenses using cross diffractive optical elements. The setup generated a robust and accurate virtual calibration grid, and the calibration was performed by rotating the camera around two axes. We propose a comparison of three fisheye mathematical models and an evaluation of the number of images in the calibration process. The comparison of our experimental data according to the 3D calibration object results showed that our technique is efficient and reliable. PMID:23669664

  4. FTIR Calibration Methods and Issues

    NASA Astrophysics Data System (ADS)

    Perron, Gaetan

    Over the past 10 years, several space-borne FTIR missions were launched for atmospheric research, environmental monitoring and meteorology. One can think of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) launched by the European Space Agency, the Atmospheric Chemistry Experiment (ACE) launched by the Canadian Space Agency, the Tropospheric Emission Spectrometer (TES) launched by NASA and the Infrared Atmospheric Sounding Interferometer (IASI) launched by Eumetsat in Europe. Others are near to be launched, namely the Cross-track Infrared Sounder (CrIS) from the Integrated Program Of- fice in the United States and the Thermal And Near infrared Sensor for carbon Observation (TANSO) from the Japan Aerospace Exploration Agency. Moreover, several missions under definition foresee the use of this technology as sensor, e.g. Meteosat Third Generation (MTG), Eumetsat Polar System (EPS) and the Premier mission, one of the six candidates of the next ESA Earth Explorer Core Mission. In order to produce good quality products, calibration is essential. Calibrated data is the output of three main sub-systems that are tightly coupled: the instrument, the calibration targets and the level 1B processor. Calibration requirements must be carefully defined and propagated to each sub-system. Often, they are carried out by different parties which add to the complexity. Under budget and schedule pressure, some aspects are sometimes neglected and jeopardized final quality. For space-borne FTIR, level 1B outputs are spectra that are radiometrically, spectrally calibrated and geolocated. Radiometric calibration means to assign an intensity value in units to the y-axis. Spectral calibration means to assign to the x-axis the proper frequency value in units. Finally, geolocated means to assign a target position over the earth geoid i.e. longitude, latitude and altitude. This paper will present calibration methods and issues related to space-borne FTIR missions, e.g. two points complex calibration algorithm, detector non-linearity, pointing errors, pointing jitters, fringe count errors, spikes and ice contamination. They will be discussed and illustrated using real data. Finally, an outlook will be given for the future missions.

  5. Improved color-image calibration

    NASA Astrophysics Data System (ADS)

    Rogers, Glenn A.; Thomas, David J.

    1995-06-01

    The technique for calibrating color imagery which has been employed by the Tank-Automotive Research Development and Engineering Center (TARDEC) includes measurement of red, green, and blue color panels using a colorimeter during the approximate time that the calibration image is captured. This method has the advantage that the luminance and chromaticity coordinates of the color panels are recorded in real time. However, the disadvantage is the amount of time it takes to measure each individual panel. Outside of a laboratory, the environment cannot be controlled, so the light level and correlated color temperature from the source may shift during the calibration period. A new technique using a spectroradiometer has been developed whereby the spectral reflectance of the color panels are measured beforehand and only the light level and spectral content from the source is monitored during the calibration period. This drastically reduces the time required for calibration, thus rendering insignificant any temporal changes in the light level or correlated color temperature of the panels. The actual luminance and chromaticity of the color panels can be calculated subsequently.

  6. Intensity calibration of DEFPOS data

    NASA Astrophysics Data System (ADS)

    Aksaker, N.; Ye?ingil, I.; ?ahan, M.

    2009-05-01

    In this study, details of the intensity calibration of Dual Etalon Fabry-Perot Optical Spectrometer (DEFPOS) were described. At TUBITAK National Observatory (TUG), The DEFPOS was redesigned so as to observe galactic H ? emission line from the diffuse ionized gas with 4' field of view (FOV) and then was located at the coudé exit of the 150 cm RTT150 telescope (?ahan et al., Research in Astronomy and Astrophysics (RAA) 9(2), 2009). The Absolute intensity calibration of the spectrometer was made by utilizing the data obtained from nine selected regions of NGC 7000 nebula. These regions were selected within 49' FOV whose intensity calibration was determined to be 850±50 R by Scherb (Astrophys J 243:644-650, 1981). One of these regions was specially selected because of its intensity for the 4' FOV was estimated as 900 R by Morgenthaler et al. (Astrophys J 563(1):451-461, 2001). For calibration of the DEFPOS data, the intensity values from Ishida and Kawajiri (PASJ 20:95-121, 1968) and the VTSS H ? maps were used and it was found that 1 ADU km s - 1 equals 2337.4 R for a 1200 s exposure time. The radial velocities and the line widths from these regions were also determined and compared with the previous results. These calibrations have been in close agreement.

  7. Internal to external wavelength calibration

    NASA Astrophysics Data System (ADS)

    Sahu, Kailash C.

    1999-01-01

    The spectra of Hen 1357 (the Stingray nebula) were used to check the internal to external wavelength calibration of the STIS first order CCD modes. The radial velocity of the Stingray nebula is known to high accuracy (< 1 km/sec) and the line with of the nebular line is very narrow (< 8 km/sec for the integrated nebula). Thus the observations of the Stingray nebula are ideal to check the internal to external wavelength calibration of the first order modes. The observations were taken in G430L and G750M modes using a 52 x 0.05 arcsec slit covering the wavelength range 2900 to 5700 A and 6295 to 6867 A, respectively. The observed wavelength range includes many nebular emission lines. The wavelengths of the nebular lines derived using the pipeline internal wavelength calibration were compared with the wavelengths derived from other ground based observations. In all cases, the wavelength match between the two is of the same order as the accuracy to which the line center can be measured. These results imply that there is no significant offset between the internal and external wavelength calibrations for these modes. The HDF-S QSO observations were also used for this test both for the first order and the Echelle modes. The results of the HDF-S QSO observations further confirm the above finding for the first order modes, and imply that there is no significant offset between the internal and external wavelength calibration for the Echelle modes.

  8. Eye movement detector calibration device.

    PubMed

    Pruchsner, William R; Zenker, Michael; Enderle, John D

    2004-01-01

    Presented is a device developed for specifically calibrating and validating the operation of Eye Movement Detectors or Monitors. The Calibrator centers on two one inch diameter HPDE spheres representing the eyes. A Laser Module is embedded in the rear of each sphere emitting a beam against a target divided in equal measurement intervals mounted as part of the device. The device moves the "eyes" about its center axes enabling the user to validate any vertical, horizontal, or X-Y combination eye position in a plus or minus fifteen degree range. Although hand controlled, the Calibrator can be motorized with stepper motors or other desired drivers. Anatomically correct sized pupils are imbedded in the front of each "eye," thereby acting as the target for whichever system is under test by the very portable Calibrator. Currently, a simple battery controlled circuit controls the laser modules and other electric requirements with accommodation for additional circuit components if required in the future. Specifically designed for validating the operation of an IR Reflective Differencing Saccadic Eye Movement Measurement System, the Calibrator can also be used with little or no alteration for validation of camera systems and other types of devices. PMID:15133997

  9. Drift-insensitive distributed calibration of probe microscope scanner in nanometer range: Virtual mode

    E-print Network

    Lapshin, Rostislav V

    2015-01-01

    A method of distributed calibration of a probe microscope scanner is suggested which main idea consists in a search for a net of local calibration coefficients (LCCs) in the process of automatic measurement of a standard surface, whereby each point of the movement space of the scanner can be characterized by a unique set of scale factors. Feature-oriented scanning (FOS) methodology is used as a basis for implementation of the distributed calibration permitting to exclude in situ the negative influence of thermal drift, creep and hysteresis on the obtained results. Possessing the calibration database enables correcting in one procedure all the spatial distortions caused by nonlinearity, nonorthogonality and spurious crosstalk couplings of the microscope scanner piezomanipulators. To provide high precision of spatial measurements in nanometer range, the calibration is carried out using natural standards - constants of crystal lattice. One of the useful modes of the developed calibration method is a virtual mode...

  10. High accuracy calibration for vehicle-based laser scanning and urban panoramic imaging and surveying system

    NASA Astrophysics Data System (ADS)

    Chen, Chanjun; Liu, Hua; Liu, Yong; Zhuo, Xiangyu

    2013-10-01

    The coordinate systems related to the vehicle-based mobile laser scanning system and the relationships between them are firstly demonstrated in this paper, then the positioning principals of vehicle-based mobile laser scanning system are well established. Factors that influence the system positioning precision are analyzed briefly, including the misalignment angle and lever arm between Scanner Owned Coordinate System (SOCS) and IMU System. To calibrate the misalignment angle and lever arm between SOCS and IMU Coordinate System, a calibration field, which uses the building corners as reference points, is established. Based on the calibration field established, a calibration method is proposed and utilized in the calibration of our vehicle-based mobile laser scanning and urban panoramic imaging and surveying system, the verification experiment show that, under good GPS conditions and with the system well calibrated, the elevation accuracy is better than 4cm and the planimetric accuracy is better than 6cm.

  11. Calibrated birth-death phylogenetic time-tree priors for bayesian inference.

    PubMed

    Heled, Joseph; Drummond, Alexei J

    2015-05-01

    Here we introduce a general class of multiple calibration birth-death tree priors for use in Bayesian phylogenetic inference. All tree priors in this class separate ancestral node heights into a set of "calibrated nodes" and "uncalibrated nodes" such that the marginal distribution of the calibrated nodes is user-specified whereas the density ratio of the birth-death prior is retained for trees with equal values for the calibrated nodes. We describe two formulations, one in which the calibration information informs the prior on ranked tree topologies, through the (conditional) prior, and the other which factorizes the prior on divergence times and ranked topologies, thus allowing uniform, or any arbitrary prior distribution on ranked topologies. Although the first of these formulations has some attractive properties, the algorithm we present for computing its prior density is computationally intensive. However, the second formulation is always faster and computationally efficient for up to six calibrations. We demonstrate the utility of the new class of multiple-calibration tree priors using both small simulations and a real-world analysis and compare the results to existing schemes. The two new calibrated tree priors described in this article offer greater flexibility and control of prior specification in calibrated time-tree inference and divergence time dating, and will remove the need for indirect approaches to the assessment of the combined effect of calibration densities and tree priors in Bayesian phylogenetic inference. PMID:25398445

  12. Calibrated Birth–Death Phylogenetic Time-Tree Priors for Bayesian Inference

    PubMed Central

    Drummond, Alexei J.

    2015-01-01

    Here we introduce a general class of multiple calibration birth–death tree priors for use in Bayesian phylogenetic inference. All tree priors in this class separate ancestral node heights into a set of “calibrated nodes” and “uncalibrated nodes” such that the marginal distribution of the calibrated nodes is user-specified whereas the density ratio of the birth–death prior is retained for trees with equal values for the calibrated nodes. We describe two formulations, one in which the calibration information informs the prior on ranked tree topologies, through the (conditional) prior, and the other which factorizes the prior on divergence times and ranked topologies, thus allowing uniform, or any arbitrary prior distribution on ranked topologies. Although the first of these formulations has some attractive properties, the algorithm we present for computing its prior density is computationally intensive. However, the second formulation is always faster and computationally efficient for up to six calibrations. We demonstrate the utility of the new class of multiple-calibration tree priors using both small simulations and a real-world analysis and compare the results to existing schemes. The two new calibrated tree priors described in this article offer greater flexibility and control of prior specification in calibrated time-tree inference and divergence time dating, and will remove the need for indirect approaches to the assessment of the combined effect of calibration densities and tree priors in Bayesian phylogenetic inference. PMID:25398445

  13. Calibration pipeline for VIR data

    NASA Astrophysics Data System (ADS)

    Carraro, F.; Fonte, S.; Coradini, A.; Filacchione, G.; de Sanctis, M. C.; Ammannito, E.; Capria, M. T.; Cartacci, M.; Noschese, R.; Tosi, F.; Capaccioni, F.

    2011-10-01

    During the second quarter of 2011 VIR-MS (VIS and IR Mapping Spectrometer) [1] aboard Dawn mission [2] has approached Vesta in order to start a long period of acquisitions that will end at the beginning of 2012. Data acquired by each instrument always require a calibration process in order to remove all the instrument effects that could affect the scientific evaluations and analysis. VIR-MS instrument team has realized a calibration pipeline which has the goal of producing calibrated (1b level) data starting from the raw (1a level) ones. The other goal of the tool has been the check of the goodness of acquired data by means of the evaluation of a series of minimum requisites of each data file, such as the percentage of the saturated pixels, the presence of spikes or the mean S/N ratio of each qube.

  14. Radar altimeter calibration using SLR

    NASA Technical Reports Server (NTRS)

    Klosko, Steven M.

    1994-01-01

    Clearly a calibration of the TOPEX altimeter (and future TOPEX-class altimeters) which is more accurate and better prepared to meet the demands of global sea level trend monitoring is warranted. TOPEX/Posideon (T/P) is in its second year of data acquisition. If it survives or surpasses the two to five year projected baseline, an unprecedented opportunity for monitoring global sea level trends at mm/y levels will have been lost due to insufficient accuracy in its altimeter calibration. It is therefore paramount to revisit the design of the T/P calibration experiment and implement a more direct approach which better utilizes the accuracy of SLR to perform this needed bias assessment.

  15. VIIRS reflective solar bands on-orbit calibration and performance: a three-year update

    NASA Astrophysics Data System (ADS)

    Sun, Junqiang; Wang, Menghua

    2014-11-01

    The on-orbit calibration of the reflective solar bands (RSBs) of VIIRS and the result from the analysis of the up-to-date 3 years of mission data are presented. The VIIRS solar diffuser (SD) and lunar calibration methodology are discussed, and the calibration coefficients, called F-factors, for the RSBs are given for the latest reincarnation. The coefficients derived from the two calibrations are compared and the uncertainties of the calibrations are discussed. Numerous improvements are made, with the major improvement to the calibration result come mainly from the improved bidirectional reflectance factor (BRF) of the SD and the vignetting functions of both the SD screen and the sun-view screen. The very clean results, devoid of many previously known noises and artifacts, assures that VIIRS has performed well for the three years on orbit since launch, and in particular that the solar diffuser stability monitor (SDSM) is functioning essentially without flaws. The SD degradation, or H-factors, for most part shows the expected decline except for the surprising rise on day 830 lasting for 75 days signaling a new degradation phenomenon. Nevertheless the SDSM and the calibration methodology have successfully captured the SD degradation for RSB calibration. The overall improvement has the most significant and direct impact on the ocean color products which demands high accuracy from RSB observations.

  16. Social and Structural Factors Associated with HIV Infection among Female Sex Workers Who Inject Drugs in the Mexico-US Border Region

    PubMed Central

    Strathdee, Steffanie A.; Lozada, Remedios; Martinez, Gustavo; Vera, Alicia; Rusch, Melanie; Nguyen, Lucie; Pollini, Robin A.; Uribe-Salas, Felipe; Beletsky, Leo; Patterson, Thomas L.

    2011-01-01

    Background FSWs who inject drugs (FSW-IDUs) can acquire HIV through high risk sexual and injection behaviors. We studied correlates of HIV infection among FSW-IDUs in northern Mexico, where sex work is quasi-legal and syringes can be legally obtained without a prescription. Methods FSW-IDUs>18 years old who reported injecting drugs and recent unprotected sex with clients in Tijuana and Ciudad Juarez underwent surveys and HIV/STI testing. Logistic regression identified correlates of HIV infection. Results Of 620 FSW-IDUs, prevalence of HIV, gonorrhea, Chlamydia, trichomonas, syphilis titers ?1?8, or any of these infections was 5.3%, 4%, 13%, 35%, 10% and 72%, respectively. Compared to other FSW-IDUs, HIV-positive women were more likely to: have syphilis titers ?1?8 (36% vs. 9%, p<0.001), often/always inject drugs with clients (55% vs. 32%, p?=?0.01), and experience confiscation of syringes by police (49% vs. 28%, p?=?0.02). Factors independently associated with HIV infection were syphilis titers ?1?8, often/always injecting with clients and police confiscation of syringes. Women who obtained syringes from NEPs (needle exchange programs) within the last month had lower odds of HIV infection associated with active syphilis, but among non-NEP attenders, the odds of HIV infection associated with active syphilis was significantly elevated. Conclusions Factors operating in both the micro-social environment (i.e., injecting drugs with clients) and policy environment (i.e., having syringes confiscated by police, attending NEPs) predominated as factors associated with risk of HIV infection, rather than individual-level risk behaviors. Interventions should target unjustified policing practices, clients' risk behaviors and HIV/STI prevention through NEPs. PMID:21541349

  17. pH Meter Calibration

    NSDL National Science Digital Library

    The North Carolina Community College System BioNetwork's interactive eLearning tools (IETs) are reusable chunks of training that can be deployed in a variety of courses or training programs. IETs are designed to enhance, not replace hands-on training. Learners are able to enter a hands-on lab experience better prepared and more confident. This particular IET delves into pH Meter Calibration, where visitors practice performing a three point calibration of a pH meter using buffer solutions.

  18. Image based autodocking without calibration

    SciTech Connect

    Sutanto, H. [Univ. of Illinois, Urbana, IL (United States); Sharma, R. [Pennsylvania State Univ., University Park, PA (United States); Varma, V. [Oak Ridge National Lab., TN (United States)

    1997-03-01

    The calibration requirements for visual servoing can make it difficult to apply in many real-world situations. One approach to image-based visual servoing without calibration is to dynamically estimate the image Jacobian and use it as the basis for control. However, with the normal motion of a robot toward the goal, the estimation of the image Jacobian deteriorates over time. The authors propose the use of additional exploratory motion to considerably improve the estimation of the image Jacobian. They study the role of such exploratory motion in a visual servoing task. Simulations and experiments with a 6-DOF robot are used to verify the practical feasibility of the approach.

  19. Method for calibrating mass spectrometers

    DOEpatents

    Anderson, Gordon A [Benton City, WA; Brands, Michael D [Richland, WA; Bruce, James E [Schwenksville, PA; Pasa-Tolic, Ljiljana [Richland, WA; Smith, Richard D [Richland, WA

    2002-12-24

    A method whereby a mass spectra generated by a mass spectrometer is calibrated by shifting the parameters used by the spectrometer to assign masses to the spectra in a manner which reconciles the signal of ions within the spectra having equal mass but differing charge states, or by reconciling ions having known differences in mass to relative values consistent with those known differences. In this manner, the mass spectrometer is calibrated without the need for standards while allowing the generation of a highly accurate mass spectra by the instrument.

  20. NIST display colorimeter calibration facility

    NASA Astrophysics Data System (ADS)

    Brown, Steven W.; Ohno, Yoshihiro

    2003-07-01

    A facility has been developed at the National Institute of Standards and Technology (NIST) to provide calibration services for color-measuring instruments to address the need for improving and certifying the measurement uncertainties of this type of instrument. While NIST has active programs in photometry, flat panel display metrology, and color and appearance measurements, these are the first services offered by NIST tailored to color-measuring instruments for displays. An overview of the facility, the calibration approach, and associated uncertainties are presented. Details of a new tunable colorimetric source and the development of new transfer standard instruments are discussed.

  1. Advancing Astrometry: Revisiting the VLBA Calibrator Surveys

    NASA Astrophysics Data System (ADS)

    Beasley, Anthony J.; Gordon, David; Jacobs, Christopher; Peck, Alison; Hodge, Jackie; Thomas, Brianna; Fey, Alan; Ma, Chopo; Gaume, Ralph; Boboltz, David; Titov, Oleg; Charlot, Patrick

    2015-01-01

    The original VLBA Calibrator Surveys (VCS) were a series of 6 VLBA campaigns from 1994 to 2007 in which more than 2000 compact extragalactic radio sources were observed at X/S bands. The goals were to obtain precise positions (uncertainties ~1 mas or better) of many hundreds of new sources for use as VLBI phase referencing calibrators, and to make snapshot images of them for morphological studies. These VCS campaigns were highly successful, resulting in accurate positions and scientific-grade images maps for a majority of sources. These observations were later used to approximately triple the number of sources contained in the second realization of the International Celestial Reference Frame by VLBI (ICRF2). However, the VCS sources in ICRF2 represent a class of 'single epoch' sources with average position uncertainties ~5 times greater than the other ~1200 ICRF2 sources which are observed much more frequently in geodetic VLBI sessions. In an attempt to greatly reduce their position uncertainties, we are re-observing ~2400 VCS sources at X/S bands on the VLBA in 8 24-hr sessions. With the recent VLBA sensitivity upgrade, the sensitivity is now nearly 5 and 3 times greater at X and S bands than the original VCS sessions. Five of these sessions have been run so far, re-observing 1500 sources. Preliminary analysis shows an improvement in the average position uncertainties by a factor of ~3.2 times for these re-observed sources. We will present and discuss these improvements and their implication for ICRF3 development (planned for 2018). Images are also being produced and examples will be presented. Additional references: VLBA Calibrator Survey : Beasley et al. 2002 2002ApJS..141...13B ICRF1 : 2009ITN....35....1M ICRF2 : 1998AJ....116..516M ICRF3 : 2014rfag.confE...1J GAIA : 2008IAUS..248..217L

  2. Stable Calibration of Raman Lidar Water-Vapor Measurements

    NASA Technical Reports Server (NTRS)

    Leblanc, Thierry; McDermid, Iain S.

    2008-01-01

    A method has been devised to ensure stable, long-term calibration of Raman lidar measurements that are used to determine the altitude-dependent mixing ratio of water vapor in the upper troposphere and lower stratosphere. Because the lidar measurements yield a quantity proportional to the mixing ratio, rather than the mixing ratio itself, calibration is necessary to obtain the factor of proportionality. The present method involves the use of calibration data from two sources: (1) absolute calibration data from in situ radiosonde measurements made during occasional campaigns and (2) partial calibration data obtained by use, on a regular schedule, of a lamp that emits in a known spectrum determined in laboratory calibration measurements. In this method, data from the first radiosonde campaign are used to calculate a campaign-averaged absolute lidar calibration factor (t(sub 1)) and the corresponding campaign-averaged ration (L(sub 1)) between lamp irradiances at the water-vapor and nitrogen wavelengths. Depending on the scenario considered, this ratio can be assumed to be either constant over a long time (L=L(sub 1)) or drifting slowly with time. The absolutely calibrated water-vapor mixing ratio (q) obtained from the ith routine off-campaign lidar measurement is given by q(sub 1)=P(sub 1)/t(sub 1)=LP(sub 1)/P(sup prime)(sub 1) where P(sub 1) is water-vapor/nitrogen measurement signal ration, t(sub 1) is the unknown and unneeded overall efficiency ratio of the lidar receiver during the ith routine off-campaign measurement run, and P(sup prime)(sub 1) is the water-vapor/nitrogen signal ratio obtained during the lamp run associated with the ith routine off-campaign measurement run. If L is assumed constant, then the lidar calibration is routinely obtained without the need for new radiosonde data. In this case, one uses L=L(sub 1) = P(sup prime)(sub 1)/t(sub 1), where P(sub 1)(sup prime) is the water-vapor/nitrogen signal ratio obtained during the lamp run associated with the first radiosonde campaign. If L is assumed to drift slowly, then it is necessary to postpone calculation of a(sub 1) until after a second radiosonde campaign. In this case, one obtains a new value, L(sub 2), from the second radiosonde campaign, and for the ith routine off-campaign measurement run, one uses an intermediate value of L obtained by simple linear time interpolation between L(sub 1) and L(sub 2).

  3. Preparation of monolithic chelating adsorbent inside a syringe filter tip for solid phase microextraction of trace elements in natural water prior to their determination by ICP-MS.

    PubMed

    Rahmi, Dwinna; Takasaki, Yuka; Zhu, Yanbei; Kobayashi, Hiroharu; Konagaya, Shigeji; Haraguchi, Hiroki; Umemura, Tomonari

    2010-06-15

    A syringe-based sample pretreatment tool, named herein "tip-in chelating monolith", has been developed for simple and facile solid phase microextraction (SPME) of trace elements in natural waters. The tip-in chelating monolith was directly prepared within the confines of a commercially available syringe filter tip by a two-step process: (1) in situ polymerization of a monomer solution consisting of 22.5% glycidyl methacrylate (GMA), 7.5% ethylene glycol dimethacrylate (EDMA), 35% 1-propanol, 28% 1,4-butanediol, and 7% water and (2) its subsequent modification with 1molL(-1) of iminodiacetate solution (adjusted to pH 10) via ring-opening reaction of epoxide. The adsorption properties of the tip-in chelating monolith thus obtained were evaluated through an adsorption/desorption experiment, where the effects of sample solution pH and eluent on the SPME of trace metals and metalloids were systematically examined. Consequently, when sample solution pH was adjusted to 5.0 and 0.9mL of 2molL(-1) nitric acid was used as an eluent, good recoveries of more than 80% were obtained for 27 elements in a single-step extraction. The proposed SPME method was validated through the analysis of two river water certified reference materials (CRMs: JSAC 0301-1 and NMIJ 7201-a). After 50-fold preconcentration (from 50mL of the original river water sample to 1.0mL of final analysis solution), 22 trace elements including Ti, Fe, Co, Ni, Cu, Ga, Cd, Sn and REEs were quantitatively determined by inductively coupled plasma mass spectrometry (ICP-MS). The analytical detection limits were in the range from 0.000003microgL(-1) for Ho to 0.18microgL(-1) for Fe. Good agreement of the observed values with the certified or reference values indicates that the proposed SPME using the tip-in chelating monolith is practically applicable. PMID:20441920

  4. Ionosphere Delay Calibration and Calibration Errors for Satellite Navigation of Aircraft

    NASA Technical Reports Server (NTRS)

    Harris, Ian; Manucci, Anthony; Iijima, Byron; Lindqwister, Ulf; Muna, Demitri; Pi, Xiaoqing; Wilson, Brian

    2000-01-01

    The Federal Aviation Administration (FAA) is implementing a satellite-based navigation system for aircraft using the Global Positioning System (GPS). Positioning accuracy of a few meters will be achieved by broadcasting corrections to the direct GPS signal. These corrections are derived using the wide-area augmentation system (WAAS), which includes a ground network of at least 24 GPS receivers across the Continental US (CONUS). WAAS will provide real-time total electron content (TEC) measurements that can be mapped to fixed grid points using a real-time mapping algorithm. These TECs will be converted into vertical delay corrections for the GPS L1 frequency and broadcast to users every five minutes via geosynchronous satellite. Users will convert these delays to slant calibrations along their own lines-of-sight (LOS) to GPS satellites. Uncertainties in the delay calibrations will also be broadcast, allowing users to estimate the uncertainty of their position. To maintain user safety without reverting to excessive safety margins an empirical model of user calibration errors has been developed. WAAS performance depends on factors that include geographic location (errors increase near WAAS borders), and ionospheric conditions, such as the enhanced spatial electron density gradients found during ionospheric storms.

  5. Hypersonic Wind Tunnel Calibration Using the Modern Design of Experiments

    NASA Technical Reports Server (NTRS)

    Rhode, Matthew N.; DeLoach, Richard

    2005-01-01

    A calibration of a hypersonic wind tunnel has been conducted using formal experiment design techniques and response surface modeling. Data from a compact, highly efficient experiment was used to create a regression model of the pitot pressure as a function of the facility operating conditions as well as the longitudinal location within the test section. The new calibration utilized far fewer design points than prior experiments, but covered a wider range of the facility s operating envelope while revealing interactions between factors not captured in previous calibrations. A series of points chosen randomly within the design space was used to verify the accuracy of the response model. The development of the experiment design is discussed along with tactics used in the execution of the experiment to defend against systematic variation in the results. Trends in the data are illustrated, and comparisons are made to earlier findings.

  6. US terrestrial solar cell calibration and measurement procedures

    NASA Technical Reports Server (NTRS)

    Brandhorst, H. W., Jr.

    1977-01-01

    A workshop was held in the fall of 1976, to evaluate and revise interim terrestrial solar cell calibration and measurement procedures. The revisions made to the interim testing procedures are described. The calibration of reference cells and the design of their holders are covered. Considerations include view angle and optical and thermal matching. Atmospheric factors which affect the calibration and performance of solar cells are discussed. The most critical atmospheric parameter appears to be water vapor. Techniques for matching reference cells to cells or arrays under test are described. Data showing errors in performance under artificial sunlight simulators due to mismatch of reference and test cells are presented. Finally, measurement procedures and data transformations needed to obtain the performance of solar cells and arrays in outdoor natural sunlight are described.

  7. The KamLAND Full-Volume Calibration System

    SciTech Connect

    KamLAND Collaboration; Berger, B. E.; Busenitz, J.; Classen, T.; Decowski, M. P.; Dwyer, D. A.; Elor, G.; Frank, A.; Freedman, S. J.; Fujikawa, B. K.; Galloway, M.; Gray, F.; Heeger, K. M.; Hsu, L.; Ichimura, K.; Kadel, R.; Keefer, G.; Lendvai, C.; McKee, D.; O'Donnell, T.; Piepke, A.; Steiner, H. M.; Syversrud, D.; Wallig, J.; Winslow, L. A.; Ebihara, T.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Owada, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Tamae, K.; Yoshida, S.; Kozlov, A.; Murayama, H.; Grant, C.; Leonard, D. S.; Luk, K.-B.; Jillings, C.; Mauger, C.; McKeown, R. D.; Zhang, C.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Piquemal, F.; Ricol, J.-S.

    2009-03-05

    We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result, the uncertainty in the size of the detector fiducial volume was reduced by a factor of two. Prior to calibration with this system, the fiducial volume was the largest source of systematic uncertainty in measuring the number of antineutrinos detected by KamLAND. This paper describes the design, operation and performance of this unique calibration system.

  8. Study of self-calibrating MEMS accelerometers

    NASA Astrophysics Data System (ADS)

    Chen, Weiping; Li, Xiangyu; Liu, Xiaowei; Yin, Liang

    2015-04-01

    Micro-electromechanical System(MEMS) accelerometers are widely used in a number of inertial navigation systems and vibration detection system thanks to their small size, low cost and low power consumption. In order to improve their performance, the accelerometers have been designed to compensate the zero-bias caused by process variations. A new method of self-calibration sensitivity applies a self-test structure to simulate standard acceleration; depending on the standard and real-time values of the accelerometer's output and by adjustment of the time division feedback, the scale factor of capacitive accelerometers can be flexibly adjusted to achieve sensitivity in self-calibrating MEMS accelerometers. Moreover, this research also uses the following: a PID feedback structure to improve the stability of the closed-loop system; a correlated double sampling (CDS) circuit to attenuate noise, which can eliminate zero drift caused by offset voltage of the pre-amplifier; a time division multiplexing electrostatic force feedback circuit to achieve the operation of a closed-loop micro-accelerometer. The structure can completely avoid electrostatic feedback coupling with a capacitance change detection circuit, which can also improve the bandwidth and stability of the accelerometer. By means of capacitance compensation array the zero-bias performance of accelerometers can be improved. The bias stability of the accelerometer can be reduced from 173mg to 31mg by testing.

  9. Absolute calibration of forces in optical tweezers

    NASA Astrophysics Data System (ADS)

    Dutra, R. S.; Viana, N. B.; Maia Neto, P. A.; Nussenzveig, H. M.

    2014-07-01

    Optical tweezers are highly versatile laser traps for neutral microparticles, with fundamental applications in physics and in single molecule cell biology. Force measurements are performed by converting the stiffness response to displacement of trapped transparent microspheres, employed as force transducers. Usually, calibration is indirect, by comparison with fluid drag forces. This can lead to discrepancies by sizable factors. Progress achieved in a program aiming at absolute calibration, conducted over the past 15 years, is briefly reviewed. Here we overcome its last major obstacle, a theoretical overestimation of the peak stiffness, within the most employed range for applications, and we perform experimental validation. The discrepancy is traced to the effect of primary aberrations of the optical system, which are now included in the theory. All required experimental parameters are readily accessible. Astigmatism, the dominant effect, is measured by analyzing reflected images of the focused laser spot, adapting frequently employed video microscopy techniques. Combined with interface spherical aberration, it reveals a previously unknown window of instability for trapping. Comparison with experimental data leads to an overall agreement within error bars, with no fitting, for a broad range of microsphere radii, from the Rayleigh regime to the ray optics one, for different polarizations and trapping heights, including all commonly employed parameter domains. Besides signaling full first-principles theoretical understanding of optical tweezers operation, the results may lead to improved instrument design and control over experiments, as well as to an extended domain of applicability, allowing reliable force measurements, in principle, from femtonewtons to nanonewtons.

  10. ECC Ozonesonde Calibration and Observations: Satellite Validation

    NASA Technical Reports Server (NTRS)

    Schmidlin, Francis J.; Zukor, Dorothy (Technical Monitor)

    2001-01-01

    The reliability of the Electrochemical Concentration Cell (ECC) ozonesonde depends on the care exercised in preparing the instrument for use. Although the ECC can be quickly prepared and flown, generally within less then one day if necessary, it is best to prepare the instrument at least one week prior to use, and as our tests have confirmed even 2-3 weeks prior to use may actually be better. There are a number of factors that must be considered when preparing an ECC. These basically are the pump efficiency, volumetric flow rate, temperature of the air entering the pump, and the background current. Also of importance is the concentration of the potassium iodide solution. Tests conducted at Wallops Island (38 N) has enabled us to identify potential problem areas and ways to avoid them. The calibration and pre-flight preparation methods will be discussed. The method of calibrating the ECC also is used at Ascension Island (8 S) and Natal, Brazil (5 S). Comparisons between vertical profiles of the ECC instrument and satellites will be reviewed as well as comparison with ground based instruments, such as, the Dobson Spectrophotometer and hand held Microtops photometers.

  11. IMU-Based Online Kinematic Calibration of Robot Manipulator

    PubMed Central

    2013-01-01

    Robot calibration is a useful diagnostic method for improving the positioning accuracy in robot production and maintenance. An online robot self-calibration method based on inertial measurement unit (IMU) is presented in this paper. The method requires that the IMU is rigidly attached to the robot manipulator, which makes it possible to obtain the orientation of the manipulator with the orientation of the IMU in real time. This paper proposed an efficient approach which incorporates Factored Quaternion Algorithm (FQA) and Kalman Filter (KF) to estimate the orientation of the IMU. Then, an Extended Kalman Filter (EKF) is used to estimate kinematic parameter errors. Using this proposed orientation estimation method will result in improved reliability and accuracy in determining the orientation of the manipulator. Compared with the existing vision-based self-calibration methods, the great advantage of this method is that it does not need the complex steps, such as camera calibration, images capture, and corner detection, which make the robot calibration procedure more autonomous in a dynamic manufacturing environment. Experimental studies on a GOOGOL GRB3016 robot show that this method has better accuracy, convenience, and effectiveness than vision-based methods. PMID:24302854

  12. Accurate Radiometric Calibration using Mechanically-Shuttered CCD Systems

    NASA Astrophysics Data System (ADS)

    Hall, D.; Liang, D.

    Acquiring accurate radiometric measurements is an essential part of characterizing non-resolvable satellites. For instance, temporal photometric signatures provide information on characteristic size, reflectance, and stability, spin rate, etc., and with more detailed analysis, shape and attitude. Multi-color photometric measurements provide information on material composition and the effects of space weathering. Thermal infrared radiometry provides gray-body temperatures and emissivity properties. Many of these methods rely on accurate radiometric calibration. For CCD systems, the calibration process generally entails removing bias and dark signals from the raw frames, dividing by a flat-field frame to account for non-uniformities, and applying a sensitivity factor to convert the remaining signal into photon-flux or energy-flux units. However, when using mechanically-shuttered camera systems, another effect must be accounted for to obtain accurately calibrated data: the finite time required for the mechanical shutter to open and close. Measurements for both two-bladed and iris mechanical shutters indicate that neglecting this effect can lead to calibration errors of 10% or more in short-duration exposures. We present methods for measuring this effect, either in a laboratory setting or with the instrument mounted on a telescope, and the additional steps required to calibrate CCD data.

  13. Calibration of CCD-Cameras for Machine Vision and Robotics

    NASA Astrophysics Data System (ADS)

    Beyer, Horst A.

    1990-02-01

    The basic mathematical formulation of a general solution to the extraction of three-dimensional information from images and camera calibration is presented. Standard photogrammetric algorithms for the least squares estimation of relevant parameters are outlined together with terms and principal aspects of calibration and quality assessment. A second generation prototype system for "Real-Time Photogrammetry" developed as part of the "Digital Photogrammetric Station" of the Institute of Geodesy and Photogrammetry of ETH-Zurich is described. Two calibration tests with three-dimensional testfields and independently determined reference coordinates for quality assessment are presented. In a laboratory calibration with off the shelf equipment an accuracy of 1120th and 1150th of the pixel spacing in row and column direction respectively has been achieved. Problems of the hardware used in the test are outlined. The calibration of a vision system of a ping-pong playing high-speed robot led to an improvement of the accuracy of object coordinates by a factor of over 8. The vision system is tracking table-tennis balls with a 50 Hz rate.

  14. Calibration of the CAT telescope

    NASA Astrophysics Data System (ADS)

    Piron, Frédéric; CAT Collaboration

    2000-06-01

    Due to the lack of test-beams in ground-based ?-ray astronomy, detector calibration has been a major challenge in this field. However, with the use of Cherenkov ring-images due to cosmic-ray muons and of strong ?-ray signals, the CAT telescope could be rather well monitored and understood. Here we present a few outstanding aspects of this work. .

  15. CALIBRATION OF SUBMERGED RADIAL GATES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calibration equations for free-flowing radial gates typically provide sufficient accuracy for irrigation district operations. However, many districts have difficulty in determining accurate discharges when the downstream water level begins to submerge the gate. Based on laboratory studies, we have d...

  16. EVALUATION OF OZONE CALIBRATION PROCEDURES

    EPA Science Inventory

    In October of 1976, the U.S. Environmental Protection Agency announced that the calibration procedure then currently in use for reference methods for the measurement of ozone in the atmosphere -- the neutral buffered potassium iodide procedure -- had been found variable and in so...

  17. INTEGRAL Cross-calibration Status

    E-print Network

    Piotr Lubinski; Pierre Dubath; Peter Kretschmar; Katja Pottschmidt; Roland Walter

    2004-05-24

    The status of the INTEGRAL cross-calibration is presented for a standard X-ray astronomy source, the Crab Nebula, as well as for some weaker sources. The relative flux normalization for the different INTEGRAL instruments is discussed together with spectral shape features.

  18. Comparison of two novel in-syringe dispersive liquid-liquid microextraction techniques for the determination of iodide in water samples using spectrophotometry.

    PubMed

    Kaykhaii, Massoud; Sargazi, Mona

    2014-01-01

    Two new, rapid methodologies have been developed and applied successfully for the determination of trace levels of iodide in real water samples. Both techniques are based on a combination of in-syringe dispersive liquid-liquid microextraction (IS-DLLME) and micro-volume UV-Vis spectrophotometry. In the first technique, iodide is oxidized with nitrous acid to the colorless anion of ICl2(-) at high concentration of hydrochloric acid. Rhodamine B is added and by means of one step IS-DLLME, the ion-pair formed was extracted into toluene and measured spectrophotometrically. Acetone is used as dispersive solvent. The second method is based on the IS-DLLME microextraction of iodide as iodide/1, 10-phenanthroline-iron((II)) chelate cation ion-pair (colored) into nitrobenzene. Methanol was selected as dispersive solvent. Optimal conditions for iodide extraction were determined for both approaches. Methods are compared in terms of analytical parameters such as precision, accuracy, speed and limit of detection. Both methods were successfully applied to determining iodide in tap and river water samples. PMID:24239760

  19. The use of anion-exchange disks in an optrode coupled to a multi-syringe flow-injection system for the determination and speciation analysis of iron in natural water samples

    Microsoft Academic Search

    Carmen Pons; Rafael Forteza; Víctor Cerdà

    2005-01-01

    A combination of multi-syringe flow-injection analysis (MSFIA) technique with an optical fibre reflectance sensor for the determination of iron in water samples has been developed in this work. Anion-exchange solid phase extraction (SPE) disks have been used as solid phase. Ammonium thiocyanate has been chosen as chromogenic reagent for Fe(III). The complex Fe[SCN]63? is retained onto the SPE disk and

  20. Hepatitis C virus seroprevalence among people who inject drugs and factors associated with infection in eight Russian cities

    PubMed Central

    2014-01-01

    Background Behavioural surveillance among people who inject drugs (PWID) and testing for hepatitis C virus (HCV) and HIV is needed to understand the scope of both epidemics in at-risk populations and to suggest steps to improve their health. Methods PWID were recruited using respondent-driven sampling (RDS) in eight Russian cities. A standardized survey was administered to collect sociodemographic and behavioral information. Blood specimens were obtained for serological testing for HCV and HIV-1. Data across the eight sites were pooled to identify individual-, network-, and city-level factors associated with positive HCV serostatus. Results Among 2,596 PWID participating in the study, 1,837 tested positive for HCV (71%). The sample was 73% male and the mean age was 28. Very few PWID reported regular contact with harm reduction programs. Factors associated with testing positive for HCV were longer duration of injection drug use, testing positive for HIV-1, sharing non-syringe injection paraphernalia and water for rinsing syringes, and larger social network size. Factors negatively associated with HCV-positive serostatus were injecting with a used syringe and two city-level factors: longer mean RDS recruitment chain in a city and higher levels of injecting stimulants. Conclusions HCV prevalence in all eight Russian cities is at the higher end of the range of HCV prevalence among PWID in Europe, which provides evidence that more resources, better prevention programs, and accelerated treatment targeting PWID are needed to control the HCV epidemic. PMID:25253447

  1. Assessing the role of syringe dispensing machines and mobile van outlets in reaching hard-to-reach and high-risk groups of injecting drug users (IDUs): a review

    PubMed Central

    Islam, Md Mofizul; Conigrave, Katherine M

    2007-01-01

    Reaching hard-to-reach and high-risk injecting drug users (IDUs) is one of the most important challenges for contemporary needle syringe programs (NSPs). The aim of this review is to examine, based upon the available international experience, the effectiveness of syringe vending machines and mobile van/bus based NSPs in making services more accessible to these hard-to-reach and high-risk groups of IDUs. A literature search revealed 40 papers/reports, of which 18 were on dispensing machines (including vending and exchange machines) and 22 on mobile vans. The findings demonstrate that syringe dispensing machines and mobile vans are promising modalities of NSPs, which can make services more accessible to the target group and in particular to the harder-to-reach and higher-risk groups of IDUs. Their anonymous and confidential approaches make services attractive, accessible and acceptable to these groups. These two outlets were found to be complementary to each other and to other modes of NSPs. Services through dispensing machines and mobile vans in strategically important sites are crucial elements in continuing efforts in reducing the spread of HIV and other blood borne viruses among IDUs. PMID:17958894

  2. Calibration of a fluxgate magnetometer array and its application in magnetic object localization

    NASA Astrophysics Data System (ADS)

    Pang, Hongfeng; Luo, Shitu; Zhang, Qi; Li, Ji; Chen, Dixiang; Pan, Mengchun; Luo, Feilu

    2013-07-01

    The magnetometer array is effective for magnetic object detection and localization. Calibration is important to improve the accuracy of the magnetometer array. A magnetic sensor array built with four three-axis DM-050 fluxgate magnetometers is designed, which is connected by a cross aluminum frame. In order to improve the accuracy of the magnetometer array, a calibration process is presented. The calibration process includes magnetometer calibration, coordinate transformation and misalignment calibration. The calibration system consists of a magnetic sensor array, a GSM-19T proton magnetometer, a two-dimensional nonmagnetic rotation platform, a 12 V-dc portable power device and two portable computers. After magnetometer calibration, the RMS error has been decreased from an original value of 125.559 nT to a final value of 1.711 nT (a factor of 74). After alignment, the RMS error of misalignment has been decreased from 1322.3 to 6.0 nT (a factor of 220). Then, the calibrated array deployed on the nonmagnetic rotation platform is used for ferromagnetic object localization. Experimental results show that the estimated errors of X, Y and Z axes are -0.049 m, 0.008 m and 0.025 m, respectively. Thus, the magnetometer array is effective for magnetic object detection and localization in three dimensions.

  3. Calibration intervals at Bendix Kansas City

    SciTech Connect

    James, R.T.

    1980-01-01

    The calibration interval evaluation methods and control in each calibrating department of the Bendix Corp., Kansas City Division is described, and a more detailed description of those employed in metrology is provided.

  4. Calibration Software for Use with Jurassicprok

    NASA Technical Reports Server (NTRS)

    Chapin, Elaine; Hensley, Scott; Siqueira, Paul

    2004-01-01

    The Jurassicprok Interferometric Calibration Software (also called "Calibration Processor" or simply "CP") estimates the calibration parameters of an airborne synthetic-aperture-radar (SAR) system, the raw measurement data of which are processed by the Jurassicprok software described in the preceding article. Calibration parameters estimated by CP include time delays, baseline offsets, phase screens, and radiometric offsets. CP examines raw radar-pulse data, single-look complex image data, and digital elevation map data. For each type of data, CP compares the actual values with values expected on the basis of ground-truth data. CP then converts the differences between the actual and expected values into updates for the calibration parameters in an interferometric calibration file (ICF) and a radiometric calibration file (RCF) for the particular SAR system. The updated ICF and RCF are used as inputs to both Jurassicprok and to the companion Motion Measurement Processor software (described in the following article) for use in generating calibrated digital elevation maps.

  5. Polarimetric and Interferometric SAR Calibration Verification Methods

    NASA Technical Reports Server (NTRS)

    Kim, Y.; Zyl, J van

    2001-01-01

    It is necessary to calibrate SAR data in order to use the data for science applications. When both polarimetric and interferometric data are collected simultaneously, these SAR data can be used for cross-calibration and verification.

  6. Automated Attitude Sensor Calibration: Progress and Plans

    NASA Technical Reports Server (NTRS)

    Sedlak, Joseph; Hashmall, Joseph

    2004-01-01

    This paper describes ongoing work a NASA/Goddard Space Flight Center to improve the quality of spacecraft attitude sensor calibration and reduce costs by automating parts of the calibration process. The new calibration software can autonomously preview data quality over a given time span, select a subset of the data for processing, perform the requested calibration, and output a report. This level of automation is currently being implemented for two specific applications: inertial reference unit (IRU) calibration and sensor alignment calibration. The IRU calibration utility makes use of a sequential version of the Davenport algorithm. This utility has been successfully tested with simulated and actual flight data. The alignment calibration is still in the early testing stage. Both utilities will be incorporated into the institutional attitude ground support system.

  7. 14 CFR 33.85 - Calibration tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.85 Calibration tests. (a) Each engine must be subjected to those calibration...

  8. An Approach to Determine the Maximum Acceptable Distortion Level in Polarimetric Calibration for Pol-InSAR Applications

    NASA Astrophysics Data System (ADS)

    Zhou, Y.-s.; Hong, W.; Cao, F.

    2009-04-01

    Polarimetric calibration accuracy is a key factor in the quantitative use of polarimetric SAR data as well as the design of future SAR system. This paper presents an approach to determine the maximum acceptable distortion level remaining after polarimetric calibration in Polarimetric SAR Interferometry (Pol-InSAR). Pol-InSAR distortion model of calibration is reviewed and discussed firstly. Then the approach to determine calibration requirements based on Pol-InSAR typical forest parameter estimation is introduced. For given forest parameters, such as mean height and extinction coefficient, Pol-InSAR data are simulated based on the RvoG model. Calibration errors are artificially added into the simulated data based on the distortion model. By the three-stage inversion process, the relationships between the estimation accuracy and calibration errors are derived. The calibration accuracy requirements are determined based on the analysis of the relationships.

  9. A Calibration of Temperature and Fire Frequency

    NASA Astrophysics Data System (ADS)

    Guyette, R. P.; Stambaugh, M. C.; Dey, D. C.

    2007-12-01

    A predictive model of fire frequency in North America using climate and human population density shows promise in estimating the importance of fire at broad temporal and spatial scales. Over 5 thousand fire scars from 120 sites and nine forest ecosystems were used to empirically derive and test a fire interval regression model. Three predictor variables were selected: a proxy of annual mean maximum temperature, annual precipitation, and human population density. The model was calibrated using mean fire intervals that document the presence of fire in a 1 to 3 km2 area during the two centuries prior to Euro-American settlement. This period allows for a more accurate calibration of temperature and fire frequency because of the reduced effects of land use, fire suppression, and other technological factors on fire events. Fifty five percent of the variance in mean fire intervals was explained by annual mean maximum temperature, 10 percent by annual precipitation, and an additional 11 percent by human population density (model r-square = 0.76). Although coarse (256 km2 cells), mean fire interval estimates provide a empirically derived and plausible depiction of the continental variability in historic U.S. fire frequency. Based on the regression diagnostics and spatial patterning in fire frequencies it is apparent that temperature is an important factor to U.S. fire regimes. We discuss the role of temperature as a 'master' variable for understanding multiple fire regime characteristics such as the rate of fuel combustion (the Arrhenius equation), the length of the fire season, and the broad scale variability of fire events. Modeling limitations, potential, and fire severity will be discussed.

  10. Radiometric Calibration of Osmi Imagery Using Solar Calibration

    NASA Astrophysics Data System (ADS)

    Lee, Dong-Han; Kim, Yong-Seung

    2000-12-01

    OSMI (Ocean Scanning Multi-Spectral Imager) raw image data (Level 0) were acquired and radiometrically corrected. We have applied two methods, using solar & dark calibration data from OSMI sensor and comparing with the SeaWiFS data, to the radiometric correction of OSMI raw image data. First, we could get the values of the gain and the offset for each pixel and each band from comparing the solar & dark calibration data with the solar input radiance values, calculated from the transmittance, BRDF (Bidirectional Reflectance Distribution Function) and the solar incidence angle (¥â,¥è) of OSMI sensor. Applying this calibration data to OSMI raw image data, we got the two odd results, the lower value of the radiometric corrected image data than the expected value, and the Venetian Blind Effect in the radiometric corrected image data. Second, we could get the reasonable results from comparing OSMI raw image data with the SeaWiFS data, and get a new problem of OSMI sensor.

  11. Calibrating Gamma Ray Bursts from SN Ia

    NASA Astrophysics Data System (ADS)

    Montiel, Ariadna; Bretón, Nora

    2011-10-01

    To consider GRBs as standard candles, the circularity problem should be surmounted. To do this GRBs are calibrated at low redshifts using SNIa data and then extrapolating the calibration to higher redshifts. In this work we apply GRBs calibration to estimate the Hubble parameter, H(z), from the luminosity distance extracted from the calibration and, knowing H(z), we study the parameter w(z) of the equation of state of dark energy.

  12. Timing Calibration in PET Using a Time Alignment Probe

    SciTech Connect

    Moses, William W.; Thompson, Christopher J.

    2006-05-05

    We evaluate the Scanwell Time Alignment Probe for performing the timing calibration for the LBNL Prostate-Specific PET Camera. We calibrate the time delay correction factors for each detector module in the camera using two methods--using the Time Alignment Probe (which measures the time difference between the probe and each detector module) and using the conventional method (which measures the timing difference between all module-module combinations in the camera). These correction factors, which are quantized in 2 ns steps, are compared on a module-by-module basis. The values are in excellent agreement--of the 80 correction factors, 62 agree exactly, 17 differ by 1 step, and 1 differs by 2 steps. We also measure on-time and off-time counting rates when the two sets of calibration factors are loaded into the camera and find that they agree within statistical error. We conclude that the performance using the Time Alignment Probe and conventional methods are equivalent.

  13. Standard Leak Calibration Facility software system

    SciTech Connect

    McClain, S.K.

    1989-06-01

    A Standard Leak Calibration Facility Software System has been developed and implemented for controlling, and running a standard Leak Calibration Facility. Primary capabilities provided by the software system include computer control of the vacuum system, automatic leak calibration, and data acquisition, manipulation, and storage.

  14. SWAT: Model use, calibration, and validation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SWAT (Soil and Water Assessment Tool) is a comprehensive, semi-distributed river basin model that requires a large number of input parameters which complicates model parameterization and calibration. Several calibration techniques have been developed for SWAT including manual calibration procedures...

  15. Calibration as parameter estimation in sensor networks

    Microsoft Academic Search

    Kamin Whitehouse; David E. Culler

    2002-01-01

    We describe an ad-hoc localization system for sensor networks and explain why traditional calibration methods are inadequate for this system. Building upon previous work, we frame calibration as a parameter estimation problem; we parameterize each device and choose the values of those parameters that optimize the overall system performance. This method reduces our average error from 74.6% without calibration to

  16. Calibration and Confidence: Where to next?

    ERIC Educational Resources Information Center

    Hattie, John

    2013-01-01

    One of the key feedback questions is "where to next?" and this article provides some directions as to where to next for research based on a review of the five articles in this special issue. The directions relate to the critical importance of calibration, the multidimensionality of calibration, the relation of calibration to self-regulation…

  17. Water content reflectometer calibration, field versus laboratory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For soils with large amounts of high-charge clays, site-specific calibrations for the newer permittivity probes that operate at lower frequencies, often have higher permittivity values than factory calibrations. The purpose of this study was to determine site-specific calibration of water content re...

  18. Calibration of a synthetic aperture radiometer

    Microsoft Academic Search

    Alan B. Tanner; Calvin T. Swift

    1993-01-01

    Calibration algorithms for a synthetic aperture microwave radiometer are presented. The calibration is geared to Earth remote sensing applications and is demonstrated on an airborne prototype thinned array imager. Two approaches to the system calibration are presented. The first utilizes commonly available reference brightness temperature scenes, such as open water, and the second utilizes data collected on the antenna range.

  19. Calibration of satellite sensors after launch

    Microsoft Academic Search

    R. S. Fraser; Y. J. Kaufman

    1986-01-01

    A simple and accurate method for the postflight calibration of satellite Visible Infrared Spin-Scan Radiometers (VISSR) is presented, and the results of inflight testing are reported. The calibration source for the VISSR with its effective wavelength of 610 nm is the radiance of sunlight, measured in calibrated reflectance units, scattered by the atmospheric gas above ocean which is far from

  20. MODIS Radiometric Calibration and Uncertainty Assessment

    NASA Technical Reports Server (NTRS)

    Xiong, Xiaoxiong; Chiang, Vincent; Sun, Junqiang; Wu, Aisheng

    2011-01-01

    Since launch, Terra and Aqua MODIS have collected more than II and 9 years of datasets for comprehensive studies of the Earth's land, ocean, and atmospheric properties. MODIS observations are made in 36 spectral bands: 20 reflective solar bands (RSB) and 16 thermal emissive bands (TEB). Compared to its heritage sensors, MODIS was developed with very stringent calibration and uncertainty requirements. As a result, MODIS was designed and built with a set of state of the art on-board calibrators (OBC), which allow key sensor performance parameters and on-orbit calibration coefficients to be monitored and updated if necessary. In terms of its calibration traceability, MODIS RSB calibration is reflectance based using an on-board solar diffuser (SD) and the TEB calibration is radiance based using an on-board blackbody (BB). In addition to on-orbit calibration coefficients derived from its OBC, calibration parameters determined from sensor pre-launch calibration and characterization are used in both the RSB and TEB calibration and retrieval algorithms. This paper provides a brief description of MODIS calibration methodologies and discusses details of its on-orbit calibration uncertainties. It assesses uncertainty contributions from individual components and differences between Terra and Aqua MODIS due to their design characteristics and on-orbit periormance. Also discussed in this paper is the use of MODIS LIB uncertainty index CUI) product.